Wival Final Document Pdf

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! Senior!Design!I! EEL!4914! ! ! ! ! WiVal! Project!Documentation! ! ! ! ! ! ! ! ! December!8th,!2008! ! Group!10! James!O’Mara! Stephen!Cover! Henry!Plange! ! ! !

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WiVal!Project!Documentation!

Table of Contents Chapter 1: Executive Summary Chapter 2: Introduction 2.1 Motivation for Project 2.2 Examples of Wireless Valet Systems 2.2.1 JTECH 2.2.2 Sindan Electrical Trading 2.2.3 ZipPark 2.2.4 Horizon Wireless 2.2.5 Wireless Valet Systems Comparison Chapter 3: Goal and Objectives 3.1 Brief Design Summary 3.2.1 The main station 3.2.2 The Portable receiver 3.2.3 The Pushbutton pager 3.2.4 The Microcontroller 3.3. Programming Code 3.4.1 Project Requirements 3.4.2 Desired Results Chapter 4: Specification and requirements 4.1 Introduction 4.2.1 The Main Station 4.2.2 The Portable receiver 4.2.3 The Pushbutton pager 4.2.4 The Antenna 4.3.1 The Microcontroller 4.3.2 Software Code Chapter 5: Research 5.1 Transmitters 5.1.1 Transmitters 5.1.2 RF Transmitters 5.1.3 RF Transmitters Parameters 5.1.3.2 Noise 5.1.3.3 Sensitivity 5.1.3.4 Dynamic Range 5.2.1 Receivers 5.2.2 RF Receivers 5.3 Antennas 5.3.2 Types of Antennas 5.3.2.1 Helical antenna 5.3.2.2 Loop antenna i! !

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5.3.2.3 5.3.3 5.3.3.1 5.3.3.2 5.3.3.3 5.3.3.4 5.4 5.5 5.6 5.6.1 5.6.1.1 5.6.1.2 5.6.1.3 5.7.1 5.9.1 5.9.2 5.9.3 5.9.4 5.9.5 5.9.6 5.10.1 5.10.2 5.10.3 5.11

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Whip antenna Antennas Parameters Antenna Gain Antenna Radiation Pattern Antenna Polarization Antenna Efficiency Encoders Decoders Power Supply Power Supply Analysis LM 317 LP3999 TPS65050 Microcontroller Push Button Pagers Pager Transmitters Isaacs TECH Two Button Transmitter Inovonics Two Button Transmitters Linx Two Button Transmitters Transmitter Comparisons Mounting Options Super Bantam Clip Bantam Clip #500 Weatherproofing

Chapter 6: Design Preferences / Component Selection 6.1 Design Preferences / Component Selection 6.2 RF Transmitters 6.2.1 RF Transmitter Selection 6.2.1.1 ES Series RF Transmitter 6.2.1.2 HP-3 Series RF Transmitter 6.2.1.3 LC Series Transmitter 6.3 RF Receivers 6.3.1 RF Receiver Selection 6.3.1.1 Microchip UHF rfRXD0420 Receiver Module 6.3.1.2 LC Series Receiver 6.3.1.3 LT Series Transceiver 6.4 Antennas 6.5 Encoders 6.6 Decoders 6.7.1 Display 6.8 Microcontroller 6.8.1 Programming Chapter 7: Final Design 7.1.1 The main station ii! !

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7.1.2 7.1.2.1 7.1.3 7.1.3.1 7.1.4 7.1.4.1 7.1.4.2 7.2 7.2.1 7.3 7.3.1 7.4 7.5 7.6 7.7

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RF Transmitter The RF Transmitter Connection The RF Receiver The RF Receiver Connection The RF Transmitter and RF Receiver Combined The Main Station Antenna The Main Station Voltage The Portable Receiver The Portable Receiver Connection The Pushbutton Pagers The Pushbutton Pager Connection PCB Final Design - Microcontroller Final Design - Software Weatherproof Casing

Chapter 8: Design Summary 8.1 The RF Transmitter Connection 8.2 The RF Receiver Connection 8.3 The RF Transmitter and RF Receiver Combined 8.3.1 The Portable Receiver Connection 8.3.2 The Pushbutton Pager Connection Chapter 9: Testing 9.1 Testing Introduction 9.2.1 The RF Transmitter 9.2.2 The RF Receiver 9.2.3 The main station and portable receivers 9.2.4 The Antennas 9.3 Microcontroller 9.4 Programming Chapter 10: Finances and Milestones 10.1 Introduction 10.2 Finances 10.3 Project Milestones Chapter 11: Final Comments

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Appendices I I II II III

Figure 7.2.1 the LR series Transmitter Pin Assignment Table 7.2.1 Pin description of the LR Series Transmitter Figure 6.2 the LR series receiver Pin Assignment Table 6.2 Pin description of the LR Series Transmitter Table 10.2

Appendix IV IV

Works Cited

Appendix V V V

Works Cited Permission Letters

Granted Permission Letters Permission Pending Letters

Table of Figures Figure…..………………………………………………….…………….……… Figure 3.4.2 Figure 4.1.a Figure 4.1.b Figure 4.1.c Figure 4.2.3 Figure 5.1 Figure 5.2 Figure 5.3 Figure 5.9.2.a Figure 5.9.2b Figure 5.9.3 Figure 5.9.4 Figure 5.9.5 Figure 5.10.2 Figure 5.10.3 Figure 5.11 Figure 6.1 Figure 6.3 Figure 6.4 Figure 7.1 Figure 7.2 Figure 7.2.1-1 Figure 7.2.1-2

Desired Results of WiVal System Basic Drawing of WiVal Units WIval Portable Receiver Block Diagram Wival Base Unit Block Diagram WiVal Push Button Pager Block Diagram RF Transmitter Components of RF transmitter General Operation Mode of HT640/S encoder Drawing with dimensions of TXM-916-ES transmitter show a block diagram of the TXM-916-ES Photograph of the 612T SmartSwitch is a picture of the battery placement in the EE1235D Linx Technologies OEM Transmitter dimensions shows the Super Bantam Clip show the Bantam Clip #500 Linx Technologies Key Fob casing Battery supply of the Linx Technologies 2 button Key Fob RH series whip antenna Permanent mount PW Series 1/4-wave whip antenna Schematic of the operations of the main station Basic antenna switches Program Overview Structure information for the sCarData structure. iv!

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Figure 7.3 Figure 7.4 Figure 7.5 Figure 9.1 Figure 9.2.1 Figure 9.2.2 Figure 9.3 Figure 9.4 Figure 9.5 Figure 9.6 Figure 10.1b

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Basic supply filters Schematic of the portable receiver The schematic of WiVal’s pushbutton pager Basic Testing Overview on the left, expected modulation delay on the right, current consumption vs. power output shows the turn on response time from VCC to PDN show the turn on response time from VCC to PDN on the left samples of expected results RSSI response time on the right shows consumption Vs power shows an Overview of WiVal’s Milestones

Table of Tables Table…..………………………………………………….………….….……… Table 5.1 Table 5.1.2 Table 5.2.2 Table 6.2 Table 6.3 Table 10.1 Table 10.2 Table 10.3 Table 10.4

Responsibility Legend Outline of the basic operations of an RF transmitter Outline of the general functions of an RF Transmitter Specifications of the LR Series Transmitter Specifications of the LR Series Receiver First Budget Final Budget Finished Milestones Future Milestones

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Executive Summary 1.1 Executive Summary The human race lives in a world where society pushes technology into our everyday lives. As years go by, technology adds ways in which people know longer use what was once considered conventional. For example, the elevator is as beneficial as an invention could be. From a perspective, one can notice that the elevator is simply a design that created an easier, more advanced way of walking up stairs. The PDA is another example of a technological product that created an innovative way of taking notes and keeping track of appointments, etc. Both of these were created not out of need but out of the encouragement of technological advances within what we do. It takes moments of driving or walking down a metropolitan area to recognize lavish restaurants and facilities that capture the eye. In this day, when a restaurant opens in fine dining or if a company has expensive clientele, it is rare not to notice a valet service that accompanies the entrance. The concept of valet as a service has been around since horses and carriages were ridden for transportation. In history, with money, comes luxury and valet is a perfect example of a luxury that wasn’t created out of need but out of the purpose of making something easier for the person who can rightfully afford the service. Since the beginning of valet, the idea of the service being a luxury is one that is unquestioned throughout the world. One could easily disagree with this statement today. Valet is a service that appears to inhabit any level of service. The traditional use of valet has been for lavish parties and restaurants that require a certain level of appearance, but in recent times, hospitals, department stores and even a few grocery markets have adopted the concept of offering their customers this service. With this expansion in the use of valet, the involvement of technology within our society is seeping into the Valet industry. WiVal will consist of three basic units that will be simple and reliable for ease of use. The WiVal will use a simple pager with two buttons that a customer will receive upon arriving to the location. That pager’s two buttons will be pressed by the customer when they want to leave or get to their vehicle. The pager will then send a signal to the Base Unit that receives and displays the requested vehicle, which will be assigned by the number that is given by the pager. The Base Unit then sends the signal to the portable receivers that a few of the employees will have on them. The three main units are all weather protected as to accommodate the weather conditions at the given areas. WiVal is another example of technology changing a traditional method. With the valet industry relying heavily on the “pen and paper” method, the concept of technology replacing this was inevitable. WiVal seeks to eliminate the use of the

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“pen and paper” method and bring forward a technological product that can accomadate customers and hopefully allow the Valet industry to profit in a way they never have. The WiVal brings a product that will only benefit the service. The companies that use this product will be moving their customer service into the next millennium. The members of WiVal have several core goals for the WiVal Project. WiVal wants to design and build a project that challenges their abilities in engineering. This project will challenge WiVal’s group in ways that ultimately become the educational “light at the end of the tunnel” in the pursuit of their engineering degrees. WiVal’s group is determined to design and build a project that will enhance themselves in their respective areas for future occupations. The WiVal design represents a challenge to the group in many ways. The areas in which the group will be challenged by this project can be grouped in two completely different categories. ! !

Explore, utilize and maximize our electrical and computer engineering skills in which we have been formally trained. Experience and gain knowledge in areas where our electrical and computer backgrounds have not trained the group. This project allows the group to venture into the unknown.

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2.1 Motivation Finding a project to settle on became an awkward task. Ideas were thrown from every direction. Ultimately the project chosen was the one that seemed the most technologically feasible and the most needed or the most likely to be used of the ideas. The motivation behind this project stems from several reasons but the root of it all comes from one of the people in the group who had prior experience within a valet company. Working within a profession allows one to see the negatives in the job that occur in everyday processes. As mentioned earlier, valet as a service has been around in some form for many years. For the last several decades, valet has employed the “pen and paper” method. The “pen and paper” method is one in which the valet employee gives the incoming person or customer a piece of paper that can later be collected and matched with the identifying ticket on the key chain. This method still works and is still used in most places that employ a valet service. This method is just another service that people who use that method are just waiting to improve. The traditional “pen and paper” method is where the improvements will be made. The disadvantages aren’t outrageous but they can clearly be improved upon by WiVal. Some of the disadvantages to the traditional method include: ! ! ! ! ! ! !

Customers have waiting times when arriving to pick up vehicle. The “pen and paper” method can be distracting to a customer. Customers often lose paper that includes identification to the vehicle they are looking for. The paper ticket can easily be lost but at the same time the ticket is so small that a person or customer doesn’t even recognize that the ticket maybe in their pocket rather than lost. Paper tickets take up lots of space in high frequency locations. If location is busy, tickets need to be on hand at all times which can be difficult due to cost and manufacturing time. Tickets are clearly paper and the paper manufacturing comes from trees.

The WiVal product allows the person or customer to take full advantage of a valet service. Though the disadvantages seem ignorable, the benefits of changing the method are worth the investment. The three main units that are part of the WiVal eliminate the problems that come from using the traditional method. The advantages of the WiVal include the following: !

Customers can avoid as much of a wait time as possible by hitting both buttons simultaneously a minute prior to needing their respective vehicle. 3!

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Restaurants want a level of class; the WiVal brings this to the table. Technological upgrades within a company show a level of progress and commitment towards giving the customers the best experience possible. The pager system is less distracting. When a customer arrives, all an employee has to do is hand a person or customer a designated receiver that goes with the vehicle and the customer can move on with their day. Paper gives the customer or person the ability to lose their car identification. Paper valet tickets are lost frequently during lavish evenings or events that require the customer to be aware or thin piece of paper. The pager given to customers is a small yet noticeable piece of equipment that looks similar to a cell phone. From experience, one notices that the the customer finds the pager easily due to its recognizable size and shape. Rarely will a pager be misplaced within a purse or pocket. The WiVal pagers allow the valet companies to avoid using as much paper. Paper costs are extremely high for imprinted tickets and this can be eliminated with the use of a pager. Within the valet industry, ordering tickets can be delayed for unknown reasons and then a chaotic mess occurs for the employees. Pagers will always be on hand. Enough pagers for parking spots and for wear and tear reasons will always be available.

As restaurants begin to flourish, so do there neighboring areas and with this the areas in which parking is available, begins to be less accommodating for their customers. This process has created a wave of companies hiring valet services to allow the customers to avoid the hassle. This project will be intended for valet companies around the world, but can also be used in clinics, hospitals, schools, restaurants, shopping centers and hotels. Currently there are few companies who manufacture similar products like the WiVal. Having experience in the valet field has allowed the group to recognize that most products do not work when customers have single button pagers. These pagers are ‘hit’ several times throughout an evening, whether by accident or for the simple purpose of amusement. This alone makes the idea a problem for the valet service. When customers ‘hit’ pagers without any intention of leaving, this creates traffic jams where the valet service is situated and it negates the whole purpose of the product, accommodation. By adding another button on a pager, the service can easily be confirmed and in within that action, accommodate the customer. WiVal would like to enter into an Industry that has few competitors. This will allow the WiVal system to be able to add specifications to the system that have yet to be made on other’s.

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2.2 Examples of Wireless Valet Systems There are currently a few companies that manufacture a product similar to the WiVal. Fortunately the WiVal can compete in a market in which there isn’t distinct leader. The companies that manufacturer these similar products are all wireless systems designers who create systems for areas in hospitality. The major company in this market is a well known Systems Manufacturer, JTECH. Like JTECH, the other companies have wireless systems that work within a restaurant for areas such as hosting, employee paging, etc.

2.2.1 JTECH JTECH is a company that is well known throughout the hospitality industry with a leading presence amongst other wireless systems manufacturers. JTECH’s design is a simple one that consists of three basic units. They created a pager for customers that are a small, black, and sleek design that has a rubber button in the middle of a plastic casing. The plastic casing is their version of weatherproofing the pager’s electrical components and also protects it from normal wear and tear damage. The second unit is the paging receiver that the valet employees carry with them while working. The receiver is similar to a traditional Motorola pager. It has the ability to store previous vehicles and to keep the notification setting to vibrate or ring. The third unit is UHF transmitter that is usually located within a building structure. The unit doesn’t display any information but it has the ability to activate new pagers and to test signal range. JTECH’s design is a simple and successful idea in which a lot of our ideas are based from. Some of JTECH’s ValetAlert specifications are: ! ! ! ! ! ! !

Their pager consists of a 900 Mhz transmitter that with a plastic weatherproof casing. A UHF transmitter that works in FM mode and that has 2 watts of power for superior signal strength. Their design for the receiver is called InstaCall. It has an LCD screen that display the paged number and works on AAA batteries. Weather casing LED notifiers Ease of pager addition to the network Small slick size (similar to a cell phone)

2.2.2 Sindan Electrical Trading (SET) Sindan Electrical Trading is another company that heavily competes in wireless systems within the hospitality industry. Their wireless systems specialize in paging for customers and employees in areas such as hotels, restaurants, 5! !

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hospitals and corporate offices. Their company’s version of a Valet paging system is known as ValetCall. The system they incorporate has a few great advantages but the flaws can’t be ignored. They have a system that still relies heavily on the “pen and paper” method. When a customer arrives, they are still given a loose leaf piece of paper. This whole process is one that the better valet paging systems are avoiding. SET’s ValetCall appears to have only two main units. A docking station and pagers are used for their system to work. When the customer or person wants their respective vehicle, they still have to go to the Valet stand to notify that they want their car. At that moment is when the customer is given a pager. This pager has an LCD screen and notifies by sound and vibration when the vehicle has arrived for pickup. When the pager notifies, the customer or persons then go to the valet stand to accept their vehicle and return the pager. Some of ValetCall’s specifications are: ! ! ! ! ! !

It has two main units: pagers and a docking station. The pagers are operated on rechargeable batteries that get their power from the docking station. Each pager has an LCD screen that displays a minimum amount of notifications. The pager rings and vibrates simultaneously when the car has arrived to the valet booth for pickup. Each docking station holds ten pagers for recharging. The docking system also allows the pager to be notified. Information on the ValetCall’s wireless specifications was not given under their general information. Pagers are designed in black and cell phone shape design. The pager looks similar to a Motorola Razr.

2.2.3 ZipPark ZipPark is a company that specializes in the Valet industry only. ZipPark is currently the most innovative of the Valet solutions in the market. They are working in small parts of the US but they are testing and selling their products within some of the most financially fiscal business around. Their system is run on their own product known as zControl. zControl is designed for usage at hotels, restaurants and airports. The system ZipPark is designed around what is known as zControl, this program has been created to work on IBM terminals that are based off windows 2000. This program is also ported to windows mobile that is used on some of the handheld PCs on the market today. Some of the handheld PCs used are the Hewlett Packard IPAQs and the Casio Casseiopeia. The training involved with the technology is an extensive program that all parking employees must attend 6! !

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due to the abundance of electronic equipment. Many of the advanced specifications that belong to the ZipPark Valet system are extremely unique from the rest of the companies. Some of their advances in technology within the industry are: ! ! ! ! !

Four desktop POS cash terminals Two IBM stand alone kiosks that allow for self payment before or after retrieving the vehicle Eight wireless realtime handheld PCs that are used parking employees during peak times to cash out customers The ability to track up to 500 vehicles a day. Data stored for repeat customers

The technology used within the ZipPark is clearly more advanced than the rest. With the advancements comes an increase in cost. The ZipPark isn’t available for direct sales. They are currently designing and perfecting their product to accommodate a larger clientele base.

2.2.4 Horizon Wireless Horizon Wireless is another company that competes in the hospitality industry. Their systems are less accommodating to the valet service industry. Their products can be used for valet, but they are generally directed towards the restaurant side. Many of their products are for employees calling or hostess calling. Their products are similar to the earlier designs mentioned. The Horizon Wireless paging system has three units. A pager is used for notification. Customers and employees are notified with a sound and vibrating feeling.

2.2.5 Wireless Valet Systems Comparison Several companies model a certain idea within the valet industry. Most of them have three bas units designed around a one way pager, base transmitter and portable receivers. JTECH stands out amongst the standard design of valet systems. JTECH’s company is a leader within the wireless design directed towards any area of the hospitality industry. Even though JTECH’s ValetAlert is a strong product, ZipPark is gearing towards a different more expensive direction. ZipPark’s system works better in standard payment parking and high frequency areas such as airports and expensive hotels. They are currently in creation stages and testing it in specific areas. Although they have a strong idea, the product is not very affordable for the common valet company. For this reason, JTECH’s design is one in which WiVal will be based from.

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Goals and Objectives 3.1 Brief Design Summary The goals and objectives of the WiVal begin with the three basic units. WiVal’s design will have a pager. The pager used is similar to JTECH’’s version in which it is designed with a one way transmitter. The second unit is the Main Station. The Main Station is similar to a ‘home base’ in which everything goes through this piece of equipment. This unit will have information being sent to it from the pager that the customer or persons are given. The Main Station has a display that alerts the employees who are nearby. The Main Station also reroutes the information to the next unit. The final unit is the portable receiver used by the employees. The unit is vital for the success of WiVal. The portable receivers are what the employees will heavily depend on to make sure a smooth shift occurs. The WiVal’s pager will be designed with a sleek, cell phone like shape that has two rubber buttons for valet notification. This unit will be as inexpensive as possible. With this in mind, the team behind WiVal recognizes that this unit will be replaced often compared to the other units. From basic wear and tear to customer damage, these all are the main reasons behind the goal of an inexpensive pager with a good weatherproof casing protecting its electrical components. The Main Station will be the main antenna and unit that controls all the information flow. It will be self powered and will also have a display for home base notification. This unit must consist of strong weatherproofing. The Main Station will have the most expensive units and thus must be protected from common weather such as rain, cold air and humidity. The main goal behind the employee receiver is to have a reliable design that is easy to use for the common worker. The receiver will have three buttons for full control. The receiver also will be fully functional under all conditions. Whether it be night or day the receiver will have a display that can be seen at all times of the day. The notification of the customer’s page will come in the form of a beeping noise and display of the vehicle number. The goal behind WiVal is to have three basic units. WiVal will be optimal for all levels of valet service. The equipment will be inexpensive and as protected as possible for maximum protection. The WiVal will accommodate to the employee who does not have a lot of technical knowledge. All of this will come together to create a strong product known as WiVal.

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3.2.1 The Main Station The main station is the broadcast center of our wireless communication design project, which sends a data envelope to all the Portable receivers within our desired range by means of an antenna delivering data through free space. An antenna would receive a communication signal from the Portable receiver and the pushbutton pager. This signal would then be passed to the microcontroller, to be added to a list of cars waiting to be returned back to the customers. Each Portable receiver decodes the data envelope to determine which car to make available to the departing customers. The output from the main station goes to a microcontroller, where appropriate interpretations are made to determine what action to take. The results are then sent in the direction of the transmitter to wirelessly send data en route for the Portable receivers. The main station has a LED component that illuminates (flashes) at the station to let the supervisor know that the message signal has been sent to the assigned Portable receivers informing the valet clerk of a customer’s departure. The main station will be used to keep track of each Portable receiver and push button pager being used on the network. A small database system will be available to keep track of fifty cars. A database server may also available for storage. This main system will be portable for easy maneuvering however it will be placed on a desk or countertop so as to allow for the connection to a nearby computer. The main station can also be mounted if desired in favor of better transmission. The connection to a computer will be accomplished by using a portable usb port built in the main station. Power to the main station would be supplied directly from a plug in wall outlet. As far design is concerned, the main station would be built in a tough and rigid plastic casing that is stylish, lightweight and waterproof.

Future upgrades There are so many ways to improve upon this design such as the use of Flash memory devices to store a database server, the addition of a touch screen LCD panel and the construction of a web based application system. These additions will allow WiVal to compete with the industry in the upcoming years. For the web based application system we can reorganize the in service techniques of the valet service. This can be done by keeping track of all license plates of vehicles, employees using the Portable receivers and the various customers using the push button pagers. The web application can then be run on a local web server as well as a being connected to the internet. With the installation of the portable usb port, we can accomplish the above upgrades as well as make our product more satisfying to interested buyers and users. 9! !

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3.2.2 The Portable receivers The Portable receiver is the central point of our communication system. The Portable receiver includes a RF receiver which receives a communication signal from one or more pushbutton pager units via the main station, informing the valet clerk of a customer’s departure. Once the communication signal is detected, the data from the receiver goes to the microcontroller, which outputs the pushbutton’s pager number to LED of the Portable receiver. With this information the valet clerk can determine which car to retrieve for the departing customer by sending a request out to the main station. Each request would then be sent to the main station thereby retrieving the car numbers from the main station. An additionally important component of the Portable receiver is the transmitter which sends a data envelope to the main station by means of a smaller antenna conveying data through free space. The antenna at the main station would receive a communication signal from the smaller antenna of Portable receiver. This signal would then be passed to the microcontroller, to be added to a list of cars that the valet clerks checked in and checked out. The LED at the main station would then illuminate when a message from the Portable receiver is sent to the main station. The Portable receiver has three function push buttons which allow the valet clerk to request the previous and next car retrieved, the previous and recent car checked in, and a clear list for retrieved cars. It also has a on/ off switch. An alerting system such as sounds (ring tone) and a vibration mode will be included in our design for the receiver, subsequently informing the valet clerk of a received signal. The car number would be displayed on two 7-segment LEDs, for a range of cars from 00 to 99. The Portable receiver needs to be powered by a constant DC source. Our desired DC source will be AA or AAA rechargeable batteries. The Portable receiver will be protected by a plastic casing that is stylish, lightweight and portable. The plastic casing will be rigid, robust, and able to withstand tumbling, run over’s, and bangs. Since the Portable receivers will be used primarily outside, it will be waterproof to withstand intense heat and cold as well as constant rainfall.

Future upgrades Since the Portable receiver is the centerpiece of our messaging system, it has the most potential for hardware upgrades. We can replace the LEDs with a LCD screen which will be used to display the messages. GPS can also be added to the design so as to keep track of the Portable receivers. The LCD can also displays data concerning current GPS position and the RF connection strength. The Portable receiver unit may also include a switch for adjusting the volume of the ringtone as well as a button for muting the speaker. The Portable receiver may also display on its front panel that the correct Transmitter currently 10! !

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broadcasting in order to avoid confusion with other networks. We also hope that we can have a clip for the Portable receiver so that they can fit securely on belts.

3.2.3 The Pushbutton Pagers The third part of our wireless communication system is the pushbutton pager which is based on an encoder and a decoder. The pushbutton pager which is given to the customers after their cars are checked in will have two buttons, which must be pressed simultaneously in order to activate a request. This two button system was designed to avoid the confusion associated with a customer accidentally hitting a button which could send out creating a confusing situation. Upon activation, the encoder in the pushbutton pager will send a messaging signal identifying itself through the antenna. Once it has been identified, the output from the pushbutton pager will go to a microcontroller, where appropriate interpretations are made to determine what action to take. The pushbutton pager will then receive a signal from the main station, which will then be decoded in addition to indicating a light on the pushbutton pager to flash and confirm the reception of the messaging signal. Powered by a button cell battery, alkaline or lithium button cell battery for a long service life and its size, the pushbutton pager may also use a rechargeable battery, which will recharge at a charging station. Bodily, the pushbutton pager will be small enough to fit into a pocket. The plastic casing will be rigid, robust, and able to endure plummeting incidents.

3.3.1 Microcontroller The microcontroller used in the WiVal system is the powerhouse that drives the system. It is responsible, not only for controlling the signals being sent between the various components, but also for monitoring these signals, and taking from them the information required in order to build an accurate list of the cars requesting pick-up. One microcontroller is installed in each main station, and another is installed in each portable receiver. The microcontroller is responsible for handling various inputs and outputs, and is more than capable of doing so during even the busiest of shifts. For inputs, the microcontroller receives signals from a variety of sources. It receives an analog signal from the antenna, which it then has to verify as a correct signal, and not just noise. It also receives input from three buttons that the user can use to interface with the system. One button will advance the list of cars in the forward direction. Another button will advance the list of cars in the reverse direction. The final button will be used in order to advance the list of cars to the most recently added car. 11! !

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The microcontroller also sends several signals through outputs. It sends analog signals to the antenna. It also sends signals to the 7-segment LED displays, in order to let the user know which car needs to be picked up. Additionally, it sends a signal to the speaker, playing a tone, so that the user knows a new car has been added to the list.

Future Upgrades There are several possible upgrades to be considered for the microcontrollers. These include expanded data storage, USB connectivity, multiple processors, and an LCD screen. All of these would benefit the WiVal system, though they would also increase the cost to the final user. Expanded data storage would be very beneficial for larger establishments, who need to keep track of a larger list of cars. The additional data storage space would also allow for more complex options, such as screen brightness (for LCD screens), programmable frequencies for when multiple WiVal systems are in close proximity, and perhaps even storage of compiled information on all cars processed, for statistical use. The additional data storage would also allow for more robust code, as the code could be made larger, allowing more in the way of verification and error checking. Overall, expanded data storage would be an excellent addition to the WiVal system, if the schedule and the resources permit. USB connectivity would allow a computer to connect to the WiVal system. This would allow the user to download statistics from the WiVal system, to obtain information such as when the busiest times are, or the average length between when a car is dropped off, and when it is picked up. These statistics would aid in the business aspect of the companies using the WiVal system. They would allow managers to better organize break schedules, or figure out just how many parking spaces to set aside for valet parking. In short, it would be another fine addition to an already impressive system. An LCD screen would allow for an improvement in the amount of data that could be supplied to the user. The current configuration, with two 7-segment LEDs has the limitations inherent to the seven segment display. With an LCD, however, any alphanumeric character could be displayed, broadening the possibilities of information. Simple graphics, for menu options and function confirmation, could even be incorporated.

3.3.2 Software The software used in the WiVal system is optimized for use on the microprocessor. It is designed to require only a very small amount of storage space, and to run the required functions efficiently. It is capable of storing the data of the last twenty cars, and then displays whichever of the twenty cars is 12! !

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requested of it. It is designed to ensure that the program does not miss any inputs.

3.4.1 Project Requirements WiVal’s design requires precision across the board. In today’s society, wireless companies are able to create Valet Pager systems that function and look aesthetically pleasing to a customer or person’s eye. The WiVal must compete in a small market but in one that has strong and consistent companies that have been developing Pager Hardware for years. Companies like JTECH, Horizon Wireless and SET have been able to build and redesign prototypes to ensure that their product is fully functional in all areas mentioned. WiVal’s requirements include: ! ! ! ! ! ! ! ! ! ! ! !

Fully functional wireless system Strong wireless signal for all weather conditions and unique wall structures Sleek and small design Inexpensive Fully Modifiable and expandable Compliable with FCC rules and regulations Weatherproof and simple wear and tear protection Pagers need to be simple and easy to use for customers WiVal Main Base Unit needs to be capable of being transported from one area to the next and power itself with a 110 V connection. WiVal Main Base Unit needs to be functional to the point that if receivers fail, it still works displaying car numbers WiVal Employee Receivers need to display numbers at all times of day (bright or dark) WiVal Pagers and Receivers need to have power last for long amounts of time

3.4.2 Desired Results WiVal’s group has high expectations about the prototype that is being built. The group expects results that satisfy the requirements mentioned earlier. The WiVal relies on simple electrical and analog signal fundamentals. WiVal’s Main Base unit should become the key component to the WiVal’s functionality. WiVal’s Main Base Unit’s dependence is shown in Figure 3.4.2. The main base should be able to power itself with a 110v outlet and easily be discarded or used for long amounts of time. WiVal’s design should allow a Valet Company to have the opportunity in deciding whether to use the Main Base Unit 13! !

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as the main wireless signal device while also using it as another way to determine what vehicles are being summoned. The group behind WiVal hopes to create a Main Base Unit that will be used by other employees who do not have portable receivers, or the valet employee who doesn’t leave the booth can coordinate around the key rack the Main Unit’s display. Some valet companies like to avoid a certain clutter around their booths so the group would like WiVal’s Main Base Unit to also have the ability to be stored in a hidden area in the booth or inside a building.

Figure 3.4.2 shows basic drawing of WiVal’s signal direction WiVal’s group would like to see that the WiVal Push Button Pager and the WiVal receiver are both functional and compatible with the WiVal Base Unit. Another result that the final product should have is the look that will please companies who purchase the product but also catch the attention of customers who use WiVal. WiVal should be able to attract customers and the aesthetic look and on the idea that the Restaurant or Building has fully committed to a Valet system. The WiVal has several technical desired results. With all that needs to work, the WiVal should be able to benefit the company employing the technology. The WiVal has a strong idea aimed towards resolving prior problems with older methods and to reach goals that Valet Companies couldn’t reach before. Some of these expectations that WiVal hopes to meet are: ! ! ! ! !

To avoid and eliminate wait lines that occupies the front of the entrance and degrades the overall look to the restaurant. Improve guest flow Maximize in profits for employees during times in which traditional ‘pen and paper’ method can slow down business Improve Valet experience and overall quality WiVal should allow the Valet Company to maximize employee work hours.

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WiVal should allow fewer employees to work and to save on labor expenses and hourly rates. WiVal should become a level of service within the Valet Industry that can separate companies from competition in the area.

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Specifications 4.1 Introduction From research, a paging system contains a main terminal or transmitter that provides the signal over a wide region. The other items include the actual customer pagers, and the employee’s portable device that receives the pager’s identification request. All work within the specified signal range that is given by WiVal’s Main Base Unit. The signal strength will in the 900 MHz range. Paging systems consist of RF technology. The pager design will consist of a transmitter that formulates, and formats the signal from the customer’s pagers and sends a message identifying the pager number to the employee’s receiver. The paging information will be coded with identification and then transmitted to the WiVal Base Unit within the specified range. WiVal’s Base Unit will then display the incoming pager number and simultaneously retransmit the signal to the WiVal’s receiver. The WiVal receiver will be able to demodulate, decode the message, and be able to recover the message and present it to the employee with the proper identifying vehicle number. In Figure 4.1.a the three units are displayed with the desired direction of signal transmission.

WiVal Overview Customer!

Employee! Base!Transceiver!

Paging/Customer’s! Unit!

Master/Receiver! Unit!

Figure 4.1.a shows a basic drawing of the units that WiVal consists of. WiVal has specific transmission ranges that are respective of FCC rules and regulations. The design will have a radio frequency range that is capable of penetrating several walls made of different types of material. At the same time the signals must be able to travel through rain. The designs are all capable of secure data transmission over high speeds. The units will all be dependable and precise under a 50m distance. WiVal needs to be reliable under several conditions. The specifications in the design are made to operate in difficult weather and they will all be weatherproof. The weatherproofing material is still under research and there hasn’t been specific choice as to which one is most 16! !

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reliable. WiVal will be able to operate properly and accurately in undesirable weather conditions such as thunderstorms and lightning. WiVal’s system is designed accordingly as to allow the easy adjustment and attachment of additional features without requiring any major design changes or complications with the systems stability. The system will have backup storage to keep all information safe in case of power interruptions or computer related issues. The range of the wireless pager system must be able to extend beyond 50 meters and in addition have the capability to transmit through walls and heavy equipments. WiVal’s main Base Unit will also be able to connect to a standard computer so as to appeal to various consumers. Another main area in WiVal’s specifications is the antennas employed. The signal directions employed in the Portable Receivers are shown in Figure 4.1.bThe antennas will be easy to mount and lightweight to avoid distracting the customer. Each antenna used in the devices is a small inexpensive attachment that is capable of sending and receiving information under the strict FCC rules and regulations.

WiVal!Receiver! Signal!from! Base!Unit

Receiver! Processor!

Display!Car! Number

Figure 4.1.b WiVal Employee Receiver Block Diagram All three units have similar specifications in the area of style. Each unit will be black and comparable to new technology in style of looks. WiVal’s design will be competitive due to its reliability with its hardware and software but also its aesthetic look as well. They will all have the WiVal symbol displayed on the casing. Each unit will be of small enough size as to accommodate for even the smallest of areas. Some basic specifications employed within WiVal are Power Supply: ! Our master terminal will connect to a regular 110V outlet. ! Pagers will use batteries (CR2032 lithium, 3V lithium, or AAA) 17! !

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Input Power will not be greater than 5 Volts

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Microprocessor: ! The microprocessor will provide fast and reliable communication. ! The microprocessor will be low in cost and available to purchase ! It will be able to process information fast and will be small in size ! Recognizable programming language platform ( Assembly, c) WiVal’s specifications for the software portion of the Main Base Unit design include the interface between microcontroller, software and hardware. These interactions are shown in Figure 4.1.c. There will be code for the master unit and base transceiver. The master unit’s code will be able to receive messages from the base transceiver. WiVal’s design is created to be easy to use. It will also be robust enough that an error in the other units does not cause failure in the master unit. WiVal will be able to display to the valet which customer is ready. WiVal will also be able to transmit to the base transceiver with information requests.

WiVal Base!Unit

Signal!Receiver!

Signal! Transmitter!

User!Input

Processor

Output/Display

Figure 4.1.c WiVal Base Unit Block Diagram WiVal’s base transceiver’s code will be able to take in signals from the paging unit. It will be able to arrange the signals in order of time received and be able to add new paging units to the system when necessary. WiVal’s programming is robust enough that an error in other units does not cause failure in the base transceiver and not be able to take in requests from the master unit, and transmit messages back. The project can be divided into six parts: The main station, The Portable receivers, antennas, the pushbutton pagers, microcontroller, and software. 18! !

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4.2.1 The Main Station As the transmission tower of our communication system, the main station plays a significant role in the transmission of data from the pushbutton pagers to the Portable receivers. This has implication for the design of the transmitters in Portable receivers, the main station and the push button pagers. Our goal is to build a RF transmission station that has a very low power consumption rate, high sensitivity to noise and other interfering frequencies and an extensive broadcasting range. We started the project with the idea of using an unambiguous performance specification for the main station. The most important parameter of our project’s performance is the intended communication frequency. Our design frequency ranged from a best performing 418 MHz to a less regulated 900MHz, that ! ! ! ! ! ! ! !

Complies to all FCC rules and regulations Has a secure data transmission Transmits data at a high speed Compatible with other rf based modules Has sufficient signal strength to transmit over 50m Has an inexpensive implementation Is precise Can penetrate through thin walls and furniture

4.2.2 The Portable receivers The purpose of the Portable receiver is to capture signals transmitted wirelessly from the main station and the pushbutton pagers through an antenna. We have two options toward accomplishing this task by purchasing a transceiver or by placing a transmitter, receiver, and antenna control on both sides of the communication link .The portable receiver should be flexible enough to correspond with other RF based transmitters with no alterations. We must overcome several limitations of the design system by minimizing the size of the RF modules and microcontroller so as to constraint the size of the Portable receiver. WiVal’s choice of architecture is primarily determined by the criteria of ! ! ! ! ! !

Complexity power dissipation High data rate Low cost modules Secure data transmission Fulfill FCC rules and regulations

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4.2.3 The pushbutton pagers In developing this model, several design considerations needed to be addressed in order to develop an appropriate pager. The general process needed for the Pager or show in Figure 4.2.3. The main concern was attaining an encoder and decoder that is small as much as necessary to correctly fit in the frame but also powerful enough to send data to the Portable receiver and the main station. In view of the fact that the main development of this project is to give customers the ability to save time and money by having a convenient and friendly communication system, this piece is designed particularly with the customers in mind. It is quite necessary to have a system by which we can have a trustworthy and consistent service. To facilitate all of this, it was useful to acquire a device with hardware which is appealing to the customer and can be easily carried around and stored in the pocket or purse. Each pager should also have a different address for which a can be changed. The areas of concern for the proposed system are: ! ! ! ! ! ! ! !

FCC rules and regulations Security Data rate Compatibility Precision Cost Durability Battery life

WiVal!Customer!Pager User!Input!

Transmitter!

Output/LED!

Figure 4.2.3 WiVal Customer Pager Block Diagram

4.2.4 The Antennas In our up-to-the-minute wireless communication system, both transmission and reception are achieved by the antenna. And as the crossing point between wireless communication systems and free space, antennas perform an important role in the transmission of data. These antennas help determine whether or not our wireless communication system can transmit accurate and reliable data. 20! !

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Antennas range in all sizes and shapes. However for this project our goal is to acquire the antennas that meet the following specifications for maximum performance and design. ! ! ! ! ! !

Portable and small in size Easy to mount and install Have an excellent frequency range Lightweight Meet FCC rules Weather proof

4.3.1 Microcontroller At least two microcontrollers will be required for the WiVal system. The main station must have one, and each portable receiver must have one. Both microcontrollers must be able to receive analog signals from the antenna, as well as be able to send analog signals to the antenna. Both microcontrollers must have large enough capacity to hold the control code. Both microcontrollers must be fast enough to handle the incoming requests. Additionally, both microcontrollers must be small enough to fit in their respective physically constructed units. The microcontroller in the main station must be able to maintain a list of all the currently activated pager units. The microcontroller must be able to add new pager units to the list, and display active pagers. The microcontroller must be able to take in a pager’s signal. The microcontroller must be able to maintain the order in which the signals arrive. The microcontroller must be able to send the signal out to the portable receiver. The microcontroller must have at least 1KB of storage space for the program. The microcontroller must have at least 1KB of RAM. The microcontroller’s footprint must be smaller than one square inch. The microcontroller must be less than one quarter inch thick. The microcontroller must be able to run on 4.5 volts or less. The microcontroller must, in fully active mode, draw less than 1 mA. The microcontroller must cost less than $50. The microcontroller will need to have at least one analog input. The microcontroller will need to have at least two analog outputs. The microcontroller will need to have at least four digital outputs. The microcontroller will need to have at least three digital inputs. The microcontroller in the portable receiver must be capable of receiving a signal from the main base unit. The microcontroller must be able to visually output to the user which number pager is next. The microcontroller must be able to handle inputs from the user for calling the next number. The microcontroller must be able to handle inputs from the user calling for the previous number. The microcontroller must be able to handle inputs from the user calling for the most recent number added to the list. The microcontroller must have at least 1KB of 21! !

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storage space for the program. The microcontroller must have at least 1KB of RAM. The microcontroller’s footprint must be smaller than one square inch. The microcontroller must be less than one quarter inch thick. The microcontroller must be able to run on 3 volts or less. The microcontroller must, in fully active mode, draw less than 1 mA. The microcontroller must cost less than $50. The microcontroller will need to have at least one analog input. The microcontroller will need to have at least one analog output. The microcontroller will need to have at least four digital outputs. The microcontroller will need to have at least three digital inputs.

4.3.2 Software All software used must be compatible with the microcontrollers, and must be able to compile to a size capable of fitting on the microcontrollers. The software will need to handle inputs and outputs connected to the microcontrollers. The software must also be able to manage a list of up to twenty active pagers. The software must be able to contain at least 500 lines of code. The software must have a total file size of less than 1KB. The software must be able to contain a structure consisting of one piece of integer data, and two pointers. One pointer must point to the next structure, and the other structure must point to the previous structure. The software must be able to order the structures into a bi-directional linked list. The software must be able to form the bi-directional linked list into a ring-like structure. The software must be able to ensure that the ring-like bi-directional linked list is capable of storing twenty cars. The software must be able to handle floating point numbers up to eight decimal places. The software must be able to handle integer numbers up to two to the eighth. The software must be able to run with only 1KB of RAM. The software must be either object oriented or function oriented. The software must be able to analyze analog data. The software must be able to pull integer data from the analyzed analog data. The software must be able to handle digital data output to multiple lines. The software must be able to send an analog signal to a speaker to produce an audible tone. The software must be able to encode an integer into an analog signal. The software must be able to then send that analog signal to a transmitter.

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Research 5.1 Research In order to effectively deliver WiVal, it is important to have an exhaustive building and implementation strategy in place to serve as the basic framework of operations. The end goal is to provide a working prototype at the end of next semester. As such, it was important to adequately research and develops ideas and methodology before formulating an implementation strategy around it. The very first step in the implementation of this project was research and development. Of course, it was imperative that the group established a clear project definition. As such, the group routinely met to brainstorm ideas about prospective ideas, with the end goal of selecting a project that presented an adequate challenge given the available resources at our disposal. WiVal proved to be the general consensus for the project to pursue based on interests and financial status shared by the group. After creating a clear and concise project definition, the next step was to seek to understand the functionalities of the WiVal prototype. The key question we sought to understand was, “What key functions do we expect this prototype to be able to perform?” This led to the initial research phase. At this research phase, each member of the team was tasked with blanket researching and documentation of important information. This documented information was discussed during team meetings. This next phase assisted the team in understanding what functionalities could actually be built given limited time and resources. Due to this, the project had to be significantly scaled back. After this, WiVal’s group began a series of more focused research geared towards achieving the goals and objectives defined. This time, the key question for the project became “What tools do we need to be able to perform the functionalities set for the prototype? “First, we brainstormed various design ideas to realize our objectives. This phase required understanding the various alternative methods of achieving our goal and agreeing on the most acceptable and practical design. Subsequently, the discussion shifted towards acquiring parts and chips for the design. There is a great amount of research that must be done in order to complete WiVal in the allotted time. The research is important in bridging our knowledge and skills of Computer and Electrical Engineering with the current state of technology. It is mainly through research that engineers gain insight into current market developments and possible solutions to any given problem. The team worked independently to gain the information we needed to provide the content of this document. A majority of the information enclosed was generated from prior knowledge gained during our education or from other sources. The 23! !

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other sources that we used were mostly available true the internet. We searched, sent emails, and browsed to find the information we needed. Our group interaction will be the key for our success in the course of this project. Various meeting times were set up to discuss the project and come up with ideas and solutions. The research done for this project, involves a wide range of items and disciplines, such as research on microcontroller, radio frequency, transceiver, receivers, power supplies, and wireless communications specifications design. These are just the items that we needed for our initial project design, but the research also spanned into topics such as product price & ease of use, ease of programmability, and feasibility of design, given limited time and resources. In view of the fact that WiVal’s group picked this project without the knowledge of how we were going to complete this task, we focused our research on understanding the fundamental concept on how our RF based messaging system will work. With a lot of time spent investigating on the internet and all the way through books in the library, WiVal’s group was proficient enough to understand the concepts that make up a communication system. Even as most of the group’s first months in class were exclusively devoted to research, the group was able to locate and strategize as a group the appropriate workings for the design and completion of the project. Following comprehensive research, the team was able to choose the appropriate parts to meet WiVal’s specifications. A vast amount of chips exist in today’s market place, all of which perform various tasks. Given this plethora of options, it became somewhat of a challenge to identify which chips would be most efficient for WiVal. It was established that to achieve the objectives earlier set, based on the acceptable design we had chosen, it was essential to split the chips analysis and research into key parts that would maximize our efficiency based on division of labor. It was agreed amongst team members to select several key parts and perform more focused research on each respective part. After selection of the chips compatible for prototype implementation, the next step is to go about acquiring those chips. Most companies send out sample chips to advertise products. WiVal’s first course of action was to try to acquire as many samples as possible in order to be able to get familiar with the technology. Unfortunately the parts the WiVal design has settled on were not available for samples. Eventually, all chips will be acquired. Each team member took ownership of one or more blocks highlighted in the block diagrams shown in Figure 4.1a. One team member took ownership of the microcontroller chips, another overseeing the transceivers and antenna, and the final group member managing the power chips portion of the project. This division of labor is captured by group member in the table shown in table 5.1. The product of this directed WiVal to in depth research in these three different components of the project which led to the initial compilation of different chips 24! !

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that could be feasible for use in the WiVal Units. It was then imperative for the team to take into consideration how easy and cost effective it was to use one chip over the other, as well as, how seamless the interfacing of various chips would be. Most of the information gathered on these chips was based off data sheets pulled from the internet, and one-on-one telephone conversations with representatives from respective companies.

Responsibility!Legend Stephen!Cover!

James!O’Mara!

Martei!Plange!

Table 5.1

5.1.1 Transmitters The purpose of wireless communications devices such as televisions is to capture electromagnetic signals through antennas and propagate them through air. This exchange of messages is carried out by a transmitter. As we studied in Analog and Digital communication class, there are an assortment of category of transmitters such as the amplitude-modulated, frequency-modulated, the phasemodulated and radar. With this in mind, this project will be centered on radiofrequency transmitter. In the electromagnetic spectrum where the RF region, referring to the electromagnetic field that is generated when an alternating current is input to an antenna, covers 10 kHz to thousands of GHz. WiVal can therefore transmit a signal in the form of electromagnetic waves traveling at the desired frequency of the group. Over the years, the advancements in the developments of transmitter have made frequency-modulated transmission an accepted standard technique for transmitting information wirelessly. Transmitting data reliably has prompted many different types of wireless devices such as mobile telephones and satellite communication systems to make use of RF fields. However one major problem wireless transmission is facing is interference between the intended message and the unwanted signals captured by the antennas such as noise which can cause data misplacements when trying to recover the original signal. The 25! !

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wireless communication system follows a line of investigation aimed to improve on the developed technology and avoid these concerns of relevance by using an RF-based transmitter.

5.1.2 RF Transmitters Wival’s wireless communication system consists of an RF Transmitter that broadcast a signal wirelessly. The designs of RF transmitters for various wireless applications require many architecture, communication and circuitry challenges to transmitters support existing analog and digital standards. As shown in the Figure 5.1 below, an RF transmitter is made up of main components which include the data modulator, a frequency oscillator, a free space point source (an antenna) and a power amplifier.

Figure 5.1 a basic RF Transmitter Unlike the RF receiver, the RF transmitter is made up of four main components outlined in Table 5.1.2. First in hand is the data modulator which deals with the exchange of baseband signal from the requested operation button. The nest component is the frequency oscillator.

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Table 5.1.2 Outline of the basic operations of an RF transmitter The frequency oscillator retrieves frequency and mixes the baseband signals from the data modulator. The power amplifier takes in frequency and transmits it to the antenna. Finally the transmitter takes the signal and propagates it through the antenna to the various receivers available.

5.1.3 RF Transmitters Parameters Since all RF Transmitter are not perfect, they have certain short comings that need to be overcome and shunned in order to satisfy the requirements for this project. The RF receiver limitations that will be considered are listed below: 1. 2. 3. 4.

Gain Noise Figure Transmitter Sensitivity Transmitter Dynamic Range

5.1.3.1 Gain Defined as the ratio of available output power to available input power, the gain plays an important role in determining the efficiency of a transmitter. Practically, a higher gain performance is achieved through an antenna. An antenna gain is described as the power output, in a specific direction, as compared to that produced in several directions by a present antenna.

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5.1.3.2 Noise In practical wireless communication systems, the transmitted signal is frequently impaired by prevailing obstruction sources. This impairment or unwanted signals trapped in the transmission data is noise. Noise is an important system parameter that is closely related to the overall receiver performance. It is commonly used to characterize the ability of a receiver to process input signals. Noise figure on the other hand is a key counter measure taken against noise through the use of noise filters. A measure of how communication systems are affected by random noise, it is designed to allow only frequencies that are lower than the cut off frequency of the filter, while attenuating other frequencies higher than the cut off frequency.

5.1.3.3 Sensitivity Sensitivity is the ability of a receiver to pick up weak signals close to noise level. It known also as the minimum input signal required to produce a specified output signal. On the other hand there is no standard description of the sensitivity level of an RF transmitter. The minimum sensitivity is determined by the transmitters’ direction, the bandwidth of a signal and the noise factor. The RF transmitters’ sensitivity also depends on the direction and size of the antenna as well as heat dissipation.

5.1.3.4 Dynamic Range The dynamic range of an RF transmitter is generally the range of signal levels in which an RF transmitter can function effectively. The ability to distinguish between different signal levels in or out of range is attributed to the transmitters’ sensitivity as well as signal strength. When it comes to selecting a transmitter, we are going to have a good balance in the midst of the noise figure, gain and dynamic range, in order to prevent performance dreadful conditions. The limitations discussed above guide us with a clear path to select the most suitable RF transmitters.

5.2.1 Receivers A receiver is made up of an interconnection of several main components of radio frequency which include RF Amplifier, a mixer, an oscillator, an IR filter and an antenna. After a signal is sent to the antenna and is confirmed by the receiver as a friendly message, it goes through to the preselecting filter which is the first component of the receiver. Next in line is a Low Noise Amplifier, which together with the preselecting filter makes up the RF Amplifier. The Low Noise Amplifier 28! !

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then boosts the signal level while reducing noise and other unwanted interferences. At that moment the Mixer takes the RF signal and converts it to a lower intermediary Frequency. This conversion is accomplished by mixing the RF signal with the Oscillator signal. Finally the IF filter removes unwanted frequency components to generate the recovered data.

5.2.2 RF Receivers The function of the receiver is to detect modulated signals in the presence of noise and interference, and demodulate the detected original signal. An RF receiver normally receives an RF signal, converts the RF signal to a baseband signal and then coupled with an antenna recovers the data. We can satisfy much of the requirement for our design by using a RF receiver. The perception of the design of a RF receiver represents a combination of specific parts illustrated in Figure 5.2 below and outlined in Table 5.2.2. As shown in table 5.2.2 below, the antenna first receives an electromagnetic signal from a nearby transmitter. Once this transpires, power is applied to the signal in the Low Noise Amplifier to increase the range of the signal.

Table 5.2.2 Outline of the general functions of an RF Transmitter

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After the signal is amplified, a noise filter is then utilized to remove all the unwanted signals that occurred after the original signal was amplified. The next stage is the mixer, followed by the local oscillators which in combination with the mixer amplify the frequency signal for a lower bandwidth and a desired frequency range. The final stage is the IR filter which sorts out all unwanted data transmitted in the original signal, for effective data recovery and interpretation.

Figure 5.2 a RF Transmitter with its basic components Although RF receivers offer a lot of advantages over other technologies, there are many design challenges involving the integration of these components into wireless communication networks. In addition because of the severe size requirements placed on the portable receivers, it is very important to define the necessary decisive factors to assist us in the selection process of a unique receiver.

5.3 Antennas Antennas have been of great interest to many manufactures and engineers in recent years because of the high demand from the wireless communication industry for improved technology. This in return has led to the development of small, lightweight and reliable antennas. The antenna plays a responsibility in the expansion of WiVal’s data transmission and reception range of broadcast, as well as the interpretation of data signals. In order to achieve an utmost range of broadcast, the team has to go with the best combination of modules and antennas. 30! !

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5.3.2 Types of Antennas As the group narrowed down the selection of receivers and transmitters, group members began an intense research for the most appropriate antennas for WiVal’s design. While researching different types of Antennas, it was found that there are three types of fundamental antennas that are a balance between size, cost, and noise. These three types of antennas are recommended and standardized for use with WiVal’s hardware design.

5.3.2.1 Helical antenna Made of conducting wire wound in the form of a helix,!this antenna is directional. The conductor wire is normally connected to a ground plane. They are also significantly smaller in size. ! ! !

A very efficient antenna given its small size They are more challenging to use in applications The antenna is prone to vigorous interference

5.3.2.2 Loop antenna The loop antenna is basically a wire coil twisted into the shape of a closed curve mainly as a sphere. Similar to the dipole with desirable characteristics, a loop antenna has a distinctive radiation pattern. ! ! !

They are frequently used for pagers They are excellent for most low cost applications They are used a lot as a receiving antenna

5.3.2.3 Whip antenna The whip antenna is the most commonly used antennas in portable RF systems. It is generally very effective and reliable with general characteristics such as rigidness and sturdiness. This antenna is known to have great antenna gain and noise rejection. ! ! !

It is a single-element antenna made out of wire This antenna offers excellent performance and signal strength Majority of the whips used today are either a 1/2 or 1/4 wave

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5.3.3 Antennas Parameters These characteristics and advantages make each type of antenna most advantageous in different situations. However, considering that one of the teams design goals was to make a small portable receiver, the team owes it to each member to take into consideration specific issues that affect the performance of an antenna.

5.3.3.1 Antenna Gain The gain is the relative increase in radiation power at the utmost peak expressed as a value in dB compared to the effective radiated power of some reference antenna. The gain is assumed to be the average maximum power. ! !

The greater an antenna’s gain the narrower the antenna’s model which in turn leads to better performance When an isotopic model is used instead of a standard dipole, its antenna gain figure is increased by approximately 2.15dB

5.3.3.2 Antenna Radiation Pattern The radiation pattern is an indication of radiated field strength around the antenna. It is normally a graphic representation used to measure the radiated electromagnetic fields of transmitted or received data from a source through an antenna. ! ! !

It also defines the way in which the radio frequency energy is propagated The radian pattern is the collective distribution characteristics of an antenna Radiation patterns are normally based on frequency and polarization

5.3.3.3 Antenna Polarization Polarization is the direction of the electric field or the orientation of the electromagnetic flux lines in an antenna. In reality, the electric field of the electromagnetic wave is always orthogonal to one another and orthogonal to the direction of propagation. The polarization quality is expressed as the ratio of copolarized and cross polarized responses. Polarization may be further classified as being curved, horizontal, vertical based on the general classification of circular and linear polarization. ! !

The polarization of an antenna is normally parallel to transmission Polarization plays a role in attaining maximum antenna range 32!

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5.3.3.4 Antenna Efficiency Antenna efficiency is the ratio of power actually radiated to the power put into the antenna terminals.The antenna efficiency is also a measure of limitation which takes into account the amount of losses within an antenna. In the above discussion, several antennas and their essential features were analyzed, in view of the fact that the wireless part of a wireless communication begins and ends with the antenna. The information acquired from these procedures will be strategically analyzed to assist in the selection of an antenna for WiVal’s miniature and efficient system.

5.4 Encoders Serving as an intermediary between data and code, the encoder could be built in the lab as we have studied in previous classes. However, the team has decided on purchasing a commercially manufactured decoder because of its sensitivity with noise and challenging design requirements. Figure 5.3 shows the genera operation of an encoder. The fundamental encoder generally uses a wireless communication medium that correlates signals to represent information. The encoder is the device that corresponds to a message sent from the main station. It does this by taking in incoming data from the main station along with a little security signal that verifies whether the inward bound data is being sent from the main station. Once this checks, a signal is sent back to the main station to validate the reception of data. Finally the data is interpreted by the encoder.

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Figure 5.3 the general operation mode of HT640/S encoder (With permission granted by Linx Technologies)

5.5 Decoders A decoder is the device responsible for receiving data from the main station, through an antenna and converts them back to messages. The decoder operates in a reverse order of an encoder and then takes the data from the antenna and produces the original message from the main station. It is important in wireless communication systems to protect against unwanted signals. As with the encoder, the decoder takes in incoming data from the main station along with a little security signal that verifies whether the inward bound data is being sent from the main station. However, the decoder checks to see whether the incoming signal contains any errors.

5.6 Power Supply Since both our RF transmitters and RF receivers do not have an internal voltage regulator, the members of WiVal are responsible as a group to provide a reliable 34! !

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and well-regulated power source. For that reason, the power supply plays an important role in our project and wireless recharging of the battery through the selected RF modules is periodically necessary. From the system content standpoint, the RF Power supply circuit must take into consideration quite a few provisions. ! ! ! !

The Power supply must be designed and tested to meet strict safety requirements. The Power supply should be small enough to fit out design. The Power supply must have efficient power saving techniques to increase battery life. The Power supply must prevent noise from affecting the performance of the RF components.

5.6.1 Power Supply Analysis While it is preferable to power the RF components from a battery, this task can also be accomplished by directly purchasing a power supply. Switch-mode Power Supplies are mainly used in today’s designs as an alternative to linear power supplies which take incoming ac voltage and step it down to a lower ac voltage. The Switch-mode Power Supplies usually take in DC input signals and normally operate at much higher frequencies than their counterparts. They are an excellent choice for WiVal’s design because of their size and efficiency. However, the Selection of a suitable power supply for this design has been limited due to the above specifications. The following are a few of the voltage regulators that the group looked examined.

5.6.1.1 LM317 – 3 - Terminal Adjustable Regulator from National Instruments Exceptionally easy to use and install, it requires only two external resistors to implement the output voltage. This voltage regulator is also capable of supplying an extended output voltage range of 1.2V to 37V. In addition to performance, it offers full overload protection. Enclosed in a standard transistor package which is easy to assemble and effortlessly adjusted to make other regulators.

5.6.1.2 LP3999 - Low Noise Voltage Regulator from National Instruments Ideally fitting for our small design, this device provides an accurate output voltage with low noise and low. Used to meet the general requirements of portable 35! !

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wireless battery powered applications, this regulator aids in the extension of battery life. The Selection of a suitable power supply for our design has been limited due to the above specifications.

5.6.1.3 TPS65050 from Texas Instruments Recommended for wireless devices that are powered by one Lithium ion batteries, the TPS65050 is designed specifically for the very small devices. Comprising of two step- down converters, this chip accommodates for low noise applications. The TPS65050 also features internal protection against short circuit currents. This device in addition has two integrated 400mA LDO and 200mA LDO voltage regulators which operate with an input voltage between 1.5V and 6.5V. After going through each voltage regulator, the group was not convinced enough to purchase one. As a result, the group is going to stick to making a voltage regulator in the senior design lab. The basic design for this case would be to connect in series a resistor with our RF component, which will be followed by a capacitor connected from the ground. The actual values for the resistor and capacitor would not be determined until the members of WiVal have actually experimented with the circuit.

5.7.1 Microcontroller Several microcontrollers were considered for use in the WiVal system. The microcontrollers were primarily those of three companies: Texas Instruments, Parallax Inc., Microchip Technology Inc. The Texas Instruments MSP430 family microcontrollers were the first microcontrollers under consideration. They are very cheap, starting at only $0.49 per chip. The MSP430 line is designed for use with either C or assembly, running on 16-bit RISC architecture. It also functions on the concept of ultra-low power, meaning it runs on 1.8-3.6 volts in active mode, and draws a maximum of 250"A when active, and only 0.1"A when not active, to retain the RAM. The Texas Instruments TMS470 family microcontrollers were the next microcontrollers under consideration. The TMS470R1B1M, specifically, costs $9.95 per chip. It is designed to be used with C or assembly, and can run using either a 16-bit or 32-bit architecture. It comes with 1MB of Flash memory, and also has 64KB of static RAM. The Texas Instruments TMS320C2000 real-time microcontroller platform families were the next microcontrollers under consideration. Pricing starts at $3.95 per chip. The TMS320C2000 line is designed for use with assembly, and runs on 32-bit architecture. They can come with up to 512KB of Flash storage, and 68KB of RAM. 36! !

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The Parallax Inc. BASIC Stamp family microcontrollers were the next microcontrollers under consideration. The BASIC Stamp 1 costs $29.00. The Stamps tend to be a bit on the large side, especially as they seem primarily designed for through-board soldering. The BASIC Stamp 1 has only 256 B for the program, or about enough for 80 instructions, and only 16 B of RAM. It runs, obviously, on a form of BASIC, known as PBASIC, which is less familiar to the group than C. It runs on 5 to 15 volts, and in active mode, draws a whopping 1mA of current, even when running at only 5 volts. The Parallax Inc. Spin Stamp microcontroller was the next microcontroller under consideration. The Spin Stamp costs $49.99. The stamps are the same size as the BASIC Stamp, and are still of the through-board soldering design. The Spin Stamp has 32KB for the program, and 32KB of RAM. It runs on Propeller Assembly, which is less familiar to the group than C. It runs on 3.3 volts. The Parallax Inc. Javelin Stamp microcontroller was the next microcontroller under consideration. The Javelin Stamp costs $89.99. The stamps are the same size as the BASIC Stamp, and are still of the through-board soldering design. The Javelin Stamp has 32KB for program storage and 32KB of RAM. It runs on a version of Java. It runs on 5 to 24 volts, and in active mode, draws an overwhelming 80mA at 5 volts, without any sort of sleep mode. The last microcontroller considered was the Microchip Technology Inc. PIC series. The PIC series is available in 8-bit, 16-bit, and 32-bit architectures. The architecture examined for the WiVal system was the PIC32, specifically the MX320. The PIC32 MX320 costs only $4.25. The chip has an impressive 32KB of storage for the program, and roughly 8KB of RAM. The PIC32 MX32000uses C programming language as it’s driving force. It runs on 2.3-3.6 volts, though no reliable information could be found regarding the current draw for the PIC32 MX320.

5.7.2 Microcontroller Programmer Kit Developer’s kits allow for easy access to the microcontrollers for the purposes of programming and debugging. For some microcontrollers, the programming kit is itself small enough to allow it to be implemented into the project. Of the companies researched, Texas Instruments and Parallax Inc. were the only ones that had developer’s kits. The Texas Instruments ez430 line was the first developer’s kit considered. It has a simple USB interface, and the chip and the kit together are small enough to fit inside a case about the size of a large flash drive. The ez430-F2013 is compatible with both the standard ez430-T2012 as well as the ez430-RF2500T. This is beneficial in the event that the group decides on making improvements that could benefit from the addition of on-chip radio communication. Additionally, the ez430-F2013 is only $20.00, and the ez430-RF2500 is only $49.00. 37! !

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Replacement ez430-T2012 boards are three for $10.00. Replacement ez430RF2500T boards are $20 each. Unfortunately, the other companies, Parallax and Microchip Technology Inc., did not have integrate-able development boards available for purchase at the time of this writing.

5.8 Research - Display The display on the portable receiving unit is the primary means by which the WiVal system will communicate with the user. The display is responsible for showing to the user which car is available for pick-up. To this end, the display must be able to, at the very least, display a range of integer numbers at least as large as the largest number of cars possible to have in the system. When looking at possible display types, the two forerunners that immediately sprang up were LCDs and LEDs, both of which had a good deal of potential in aiding the WiVal system. LEDs were looked at for their simplicity of use, and also for their low cost. A seven segment LED can be purchased for less than a dollar, and all that is required is to hook up a resistor and power, and it is fully functional. Additionally, an LED draws very low power compared to other types of displays, extending the battery life for portable devices, and saving on utility bills for stationary, wallpowered devices. The downside is that there are severe limitations as to what an LED is capable of displaying. A seven segment display is not really capable of displaying more than digits, and perhaps a few letters. However, for the purposes of the WiVal, two seven segment displays would be able to display digits from 00 to 99, which should be more than enough for all but the largest of businesses. Also, LEDs are rather durable, and fingerprints, bumps, and scratches are all unlikely to damage an LED beyond use, except in the most extreme cases. LCDs, on the other hand, can be much more versatile. Some LCDs are capable of displaying any number of characters, or even graphics. However, they do draw considerably more power than LEDs. Also, they are considerably more delicate. An LCD that is not protected can be scratched through normal use. It is also considerably easier to crack an LCD screen, and even simply touching one with a bare finger can, over time, dirty it to the point of hampering it’s use. Another disadvantage with LCDs is their cost, which can be prohibitively high, and moreover, the fact that ready-to-use units are extremely scarce. In fact, no mass-produced LCDs fitting the requirements of the WiVal system were available for purchase for commercial purpose at the time of this writing.

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Due to the scarcity of LCDs, it was decided that LEDs were a far better choice. Though using them would mean limiting the amount of information capable of being displayed, it was felt that all of the necessary information could be carried out via LEDs. Additionally, the lower power consumption and higher overall durability of LEDs mean less long-run cost to the consumer, which will make the WiVal system more desirable for purchase.

5.9.1 Push Button Pagers Paging transmitters consist of RF technology. We are hoping to design or find a transmitter that receives, formulates, and formats the signals from the customer’s pagers and sends a message identifying the pager number to the employee’s receiver. The paging information should be coded with identification and then transmitted to all receivers within range. WiVal has done extensive work in research with the pager. We have come across several ideas utilizing LEDs that activate an area on the pager that light up when pager has worked. It is a certainty that the customer or even the employee can lose the pager. Cost in this item is more important than others because we want the valet company to be able to replace pagers as inexpensively as possible or expand and by more as business increases. In comparison to other companies, several designs include a one button pager. From experience, valet employees realize that the one button pager can be a major distraction to the employees on duty. The one button pager is extremely susceptible to accidental hitting. Often times, customers or people in the group have the pager in their pocket. With this came several instances in which key, phones, coins, etc end up hitting the button and accidently notifying the employees to retrieve the vehicle that isn’t needed yet. Another example of a problem associated with the one button pager, is kids. On several occasions when customers arrive with kids, the child or children decide to take or ask for the pager. When this happens, children consistently hit the button without any knowledge of the ramifications involved. Kids will hit the button numerous times over the course of a shift. All of this had made the decision for WiVal simple. Our research in this pager will be directed towards a way of creating or finding a two button 900 MHz pager (transmitter). With the two button pager, the problems will be avoided due to the necessity of a simultaneous push, which would occur less often during shifts. Another major factor involved in researching this unit is in which way power can be maximized. WiVal’s reliability is very dependent on how long it lasts. One of WiVal’s goals is to have the equipment last for a long time and finding ways of power was a main area we spent time on. We asked ourselves the question, “Will this be powered by basic batteries? Lithium batteries? Will this pager be rechargeable?” These are all major questions that were researched for the most 39! !

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optimal design. With our research, we found that to design the power supply could end up being major time consumption in comparison to all the allocated time we have to design and build everything. This led to a few paths. We originally wanted to create the pager and choose the battery, but WiVal was put in a corner and had to choose a different direction. An area that can’t be neglected is in the protection of the vital electronics that the WiVal Pager consists of. The pager will be used in all weather conditions. Valet companies who work in southern areas need a casing that can protect against rain and humidity. Valet Companies who are located up north are in an area that is susceptible to freeze and these units need to be as freeze resistant as possible. WiVal’s Pager research included the types of protection that can be used to maximize life of the WiVal Push Button Pagers. Studying designs in the market, WiVal knows that this is the unit that needs to be the most aesthetically pleasing. This unit is the one that is given to the customer or person who will valet their vehicle. With that in mind, WiVal realizes the importance that this first impression can make for the rest of the service. Valet Industry usually works on tips and in this respect, WiVal needs to benefit the valet company, not diminish its worth. Several customers, who valet, aren’t familiar with the technology that is being spread into the Valet Industry. If a customer comes to valet service, WiVal wants the customer or person to be stunned at the fact that a company or restaurant has committed to higher level of service. The WiVal Pager is essential to the success of this project. With our research we will try to move forward with the most cost effective and aesthetically pleasing method that works. All of this has come to truly affect the direction that WiVal is taking the Pager. At first our research put us on a path towards designing and building our own pager. This led to several conclusions: ! ! ! ! ! ! !

WiVal Pager needs to have a long battery life Design in the WiVal Pager needs to be as little time consuming as possible for completion of WiVal Design in the WiVal Pager needs to be eye-catching Simple and Easy Small yet distinguishable Two buttons instead of one Inexpensive (Under $50)

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5.9.2 Pager Transmitters We found only a few transmitter chips that were capable of implementing the actions needed for the WiVal Pager to succeed. The main example of the transmitters researched was the Linx technologies ES transmitter TXM-916 shown in Figure 5.9.2.a. The TXM-916-ES module is a single-channel transmitter designed for the wireless transfer of digital or analog information. The TXM-916-ES is capable of sending signals over distances of up to 1,000 feet outdoors and up to 500 feet indoors. These chips are extremely cost effective in comparison to other FM transmitters. This chip is designed for use of 900 MHz band. This allows the capability of a strong stable signal. 900 MHz allows the ability and meets the goal of having a transmitter that can send a signal through various types of structures. Several structured walls in facilities or restaurants can create problems that eliminate wireless signal usage. With a 900 MHz signal, WiVal can conform to FCC rules and regulations and create a design that meets our specifications. Similar to other Linx ES equipment, these chips requires no other external components except the purchase of an antenna. Some of the key capabilities of this chip are: ! ! ! !

Wireless Data transfer Low power consumption Compact design Great cost/performance ratio

Figure 5.9.2.a Drawing with dimensions of TXM-916-ES transmitter (Permission granted by Linx Technologies) This chip is truly capable of catering to several needs and requirements that WiVal consists of. This chip is also cost effective which is one of the main objectives to this unit. To further understand the design aspect of the TXM-916ES the block diagram in Figure 5.9.2b illustrates the components that consist of this chip. 41! !

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Figure 5.9.2b show a block diagram of the TXM-916-ES (Permission granted by Linx Technologies)

5.9.3 Isaacs TECH Two Button Pager After plenty of research, WiVal’s group noticed that to design a pager with the requirements needed, would be a strenuous task. In today’s technological society, creating a pager could easily become a project in itself. We previously mentioned the Linx TXM-196-ES and its capabilities. This product created by Isaac TECH is a product that is comparable to what WiVal needs. Like JTECH and other companies, the pushbutton pager is sometimes manufactured by outside companies like Isaac Tech. Isaac designed and created a transmitter that has the proper signal transmission in the area of 900 Mhz. This transmitter’s signal transmission of 900 MHz allows the signal to travel through walls and structures. Several signals have trouble traveling through restaurant structures, so WiVal’s ideal area is around 900 MHz. The transmitter described is the 612T SmartSwitch Handheld transmitter shown in figure 5.9.3.

Figure 5.9.3 Photograph of the 612T SmartSwitch (permission pending from Issacs Tech) 42! !

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Isaacs Tech’s design is extremely optimal for everything needed for the WiVal Push Button Pager. One of the major specifications involved within WiVal is the ability to withstand normal wear and tear and protect itself from major weather conditions. The 612T has a design that is perfect for common wear and tear. The design is a strong plastic that keeps all internal components in place and protects them from customers or employees dropping them accidently. The design also incorporates the two buttons, one function design that follows our initial motivation. This two button concept allows for a stronger protection against accidental hitting. The accidental hitting is a major reason for the creation and improvements of WiVal over other Valet Systems in the market. Another key specification of the 612T is its weather protection. The 612T has been tested in high levels of humidity and has been tested in a cold chamber a temperature below -30 degrees Celsius. Isaacs Tech power supply is one that stood out amongst other products. It utilizes a 3V lithium battery. This battery is expected to have a lifetime of three to five years. This lifetime is perfect for satisfying the requirements of potential WiVal clients. The 3V lithium battery design eliminates the need for a recharging power supply or the need to create a recharging dock. The 612T is a product we stumbled open during research. These transmitters appear to be an optimal choice for WiVal.

5.9.4 Inovonics Two Button Transmitter Inovonics is a wireless company that specializes in components such as transmitters, repeaters and receivers. The last transmitter discussed was the Isaacs TECH 612T. The 612T is a product that appears to be a great fit for WiVal’s specifications and requirements. After assuming to have found the optimal transmitter, we continued to research a few more transmitters. We stumbled upon the Inovonics EE1235D pendant transmitter. This transmitter appears to be the competition to the 612T smartswitch. The Inovonics transmitter’s signal transmission of 900 MHz allows the signal to travel through walls and structures. Several signals have trouble traveling through restaurant structures, so WiVal’s ideal area is around 870 MHz. The Inovonics design also includes a lithium battery that is suited for a long battery life similar to the 612T. The battery placement is shown in figure 5.9.4.

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Figure 5.9.4 is a picture of the battery placement in the EE1235D (permission pending from Innovonics) The EE1235D has a design that will protect itself against the everyday use of the Valet Industry. The Inovonics transmitter has a strong plastic design similar to Isaacs Tech’s 612T. The EE1235D has a two button, one function design as similar to the one shown in figure 5.9.3. The Inovonics transmitter is another product that appears to fit well for WiVal. One specification that wasn’t clear was whether this product was FCC compliable. We couldn’t find out whether this product is aimed towards European markets instead of American.

5.9.5 Linx Key Fob Transmitter After further research, the group was able to find a transmitter that may outdo the others being considered. Linx manufactures a key fob known as the Linx OEM Transmitter. The Linx OEM Transmitters is has similar functions as the other transmitters mentioned. The Linx OEM transmiiter can be purchased in several different specifications that accommodate designs such as: ! ! ! ! !

Amount of buttons (1,2,3,4,5) Color for a restaurant aesthetic matching Weatherproofing (plastic protection) Size FCC certified

The Linx OEM transmitter is a small compact key fob that allows for FCC compliance under the range of 433.92 Mhz. This range allows for a distance up to 1000 ft. The Linx OEM transmitter is ideal for usage in situations of remote control and command operations. The Linx OEM transmitter shown in Figure 5.9.5 is a general look for the transmitter sold by Linx technologies. The other pagers manufactured by them are with more buttons and look similar but with added rubber. The Linx OEM transmitters power themselves with a single 3V 44! !

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CR2032 lithium battery. benefit WiVal are: ! ! ! ! !

The linx OEM transmitter’s specifications that can

Configuration for two button one function transmission needed for WiVal’s requirements Up to 1000 ft of range Selectable addressing for security and accuracy Up to 1024 receiver transmitter relationships Cost effective (range from $20- $40 dependent on amount of buttons chosen)

Figure 5.9.5 Linx OEM transmitter and its dimensions (Permission granted by Linx Technologies)

5.9.6 Transmitter Comparison The last four transmitters mentioned are all well built components. With this in consideration it became difficult to narrow down a selection to move forward with. We originally started our research in looking for a transmitter that could be purchased and then designed around. After design, we would implement our own weatherproof casing. With further research, we ran into better more accommodating transmitter components. This led us to possibly adapting a push button pager that has already been designed but not programmed. The 45! !

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specifications needed in the transmitter for WiVal that were adamant to our research are: ! ! ! ! ! ! ! ! ! !

Two button one function Programmable for addressing Battery life that allows for minimum worries (lithium batteries preferable for long life 2 - 4 years) Weatherproofed for rain, snow, humidity, and cold weather Aesthetically pleasing for customer Small in size for pocket or purses Cost effective (under $40) Compatible with mentioned microcontrollers and receivers in Chapter 4 FCC compliant Range and signal strength that accommodates for all wall structures and respective distances

All pagers researched allowed for most of these specifications. Ultimately WiVal settled on pager. The pager that appears most suited for WiVal appears to be the LINX Technology OEM Transmitter. All of this works best for the conditions that are required for WiVal’s success. The LINX OEM transmitter will allow WiVal to move forward and capitalize on the necessary specifications.

5.10.1 Mounting Options Two of the main units of the WiVal System are designed for portability. The WiVal Push Button Pager is designed for the customers to carry. As an option for customers who don’t like items in their pockets, WiVal is researching the ability of designing or purchasing a belt clip that can attach to any of the researched push button pagers. The belt clip concept can be excluded on the Push Button pager if costs get higher than expected. Though WiVal may exclude the belt clip for a Pager, the Portable Receiver absolutely requires a belt or body attachment. The Main Base Unit mounting options are rather simple. The Main Base Unit will be laid down or stood up on the valet stand while being connected to a power outlet.

5.10.2 Super Bantam Clip Of the researched clips, one of the designs that WiVal is interested in is the Super Bantam Clip. This clip is a small black plastic piece (shown in Figure 5.10.2) that can be glued and attached to any other piece of solid material with the included 3M VHB removable adhesive. The Super Bantam attaches by squeezing the ends to clip onto a belt. This clip has the capability of working on 46! !

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both the WiVal’s Push Button Pager and the Portable Receiver. The Bantam Clip fulfills our specifications and it cost is $6.00.

Figure 5.10.2 shows the Super Bantam Clip (Permission pending from theclip.com)

5.10.3 Bantam Clip #500 This is another clip from the same company who made the Super Bantam Clip. It is similar in that it is small slick and black (show in Figure 5.10.3). The material is also made out of plastic. The key difference is that the Bantam Clip #500 has a clip that is removable instead of needing to squeeze every time. The Bantam #500 allows for WiVal to be used in fast swift motion without having to take the whole clip off each time.

Figure 5.10.3 show the Bantam Clip #500 (Permission pending from theclip.com)

5.11.1 Weatherproofing WiVal’s design requires everything to be weatherproofed. Each component within each unit cannot be exposed to any kind of extreme weather. Rain, snow, humidity or cold temperatures can affect the components within the Main Base Unit, Push Button Pager and Portable Receiver. The Push Button Pagers that are under research are all qualified for several different weather conditions. The Push Button Pagers will be purchased and all manufactured with a plastic casing for protection and aesthetics. The pagers all have rubber material protecting the 47! !

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button portion from wear and tear. The design shown in Figure 5.11 shows the weather casing on the Linx Technologies Key Fob.

Figure 5.11 Linx Technologies Key Fob casing (Permission Granted from Linx Technologies) Each unit will have as maximum of protection as possible under the budget that was made for WiVal. The weather casing will be water proof and be strong enough from breaking easily when dropped. The Portable Receiver and the Main Base Unit are both being designed by the WiVal team. Each unit will have components on a board. When the board’s final dimensions are complete, WiVal’s group can accommodate the plastic housing to fit. The housing that we researched is basic plastic that can be cut or molded to fit anything. Several companies sell the type of plastic needed for WiVal such as Ben Franklin’s, Michaels or hobby shops. A plastic company that has caught the attention of WiVal’s group is Tap Plastic. This company manufactures all levels of plastics from all sizes and dimensions. The plastic WiVal’s group is researching, is a type of PVC plastic sheet. These sheets can be ordered in small dimensions and then cut and sized down to accommodate the unit it is housing. The plastic is weatherproofed by being water resistant and cold weather does not permeate through as naturally due to the thickness and material of the PVC sheet. The sheets are the color and aesthetically pleasing material that WiVal is trying to acquire. These sheets are sold at the low price of $7 a square foot. 48! !

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Design Preferences 6.1 Design Preferences / Component Selection The hardware section of this report will document the planning, research, and design of the hardware section of the WiVal Project. The hardware section is made up of six main parts: the Main Base Station, the Portable Receiver, the Push Button Pager, software and communications. When combined and integrated with the WiVal software, the hardware will provide the physical means by which WiVal can fully function and maximize its potential. Unique to most senior design projects, the specifications and requirements for this piece of hardware had no predefined schematics or designs by existing systems, rather than WiVal being able to adopt and modify an older project. These requirements forced the hardware to be designed based on our specific needs and requirements. The units being designed are nonexistent for a consumer to purchase in today’s market. A company can finance a wireless company to engineer the systems, but rarely will these systems be sold to common companies without proper planning for manufacture. When compared to any of the traditional Wireless Valet systems in operation in today’s industry, the WiVal project has a very small data processing requirement. The project’s small processing requirements mean that the Main Base Unit needs only minimal processing capabilities. This fact should prove to be a benefit to the project in that a second hand personal Receiver which is similar to a portable Main Base Unit that will make a sufficient master station computer for valet employees that are currently away from the valet stand. Though the Portable Receiver may have plenty of technical capabilities, this unit and the Push Button Pager rely on the Main Base Unit for functionality. The concept of the design is to put together an arrangement of explicit parts capable of accomplishing our goal of a successful wireless Valet system known as WiVal. Initially WiVal’s group had high expectations for the optimization of this project to effectively transmit data from the customers to the main station and then the valet clerk. Through all of the planning and design, our expectations were met with the chosen component selection. Most of the components are acquirable from Linx Technologies. This company has provided WiVal with the opportunity to purchase components that will be capable of WiVal’s specifications and affordable to WiVal’s budget. The Main Base Unit is the projects biggest hardware and software challenge. WiVal’s research and planning has led the group to a specific path in the field of RF technology. The components needed for the project include RF transmitters, receivers and transceivers. The Main Base unit will utilize all the skills that the 49! !

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group’s engineers have come to learn. The Main Base Unit has three basic requirements: ! ! !

It must be able to receive input data from the Push Button Pagers that are being occupied by customers It must be able to process this data into a usable format It must be able to transmit the data to the Portable Receivers being operated by the Valet employees

The Main Base Unit will be compromised of four main components. The Main Base Unit has a Linx Technologies LR receiver and antenna. The antenna is used for the long range signal transfer that will help the receiver acquire the information sent from the customers. The Linx LR receiver will then send the Push Button Pager info to an RF microcontroller that will then send the signal to a LED displaying the car number. This process is then being done simultaneously while the same signal is being sent to the Linx Technologies LR Transmitter to send the formatted signal to a valet employee’s Portable Receiver. The Valet Employee’s Portable Receiver has a Linx Technologies LR receiver similar to the Main Base Unit’s that captures the signal identifying the car number being sent by the Push Button Pager via the Main Base Unit’s receiver. The four main components to the Main Base Unit are: ! ! ! ! !

RF Receiver RF Transmitter LED RF Microcontroller Antenna

Each unit has its own way of supplying power. Each unit has to have an acceptable means of energy supply by American power standards. The supply and storage of power place constraints on the features and physical form of the final product. Determining the energy source, what medium is used to store the chosen form of energy, and the means by which it is distributed are essential issues for a prototype that must be resolved by compromising. Two conflicting requirements are the number of features and the size of the end product. The more features there are, the larger the power requirement, and hence supply which must fit inside the units. The power supply for WiVal’s Push Button Pagers and Portable Receivers will be power by lithium CR 2032 batteries for long life and small size. The WiVal Push Button Pager’s batter supply is show in Figure 6.1. WiVal’s Main Base Unit’s power components are designed to power itself from a standard power connection.

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Figure 6.1 Battery supply of the Linx Technologies 2 button Key Fob (Permission Granted from Linx Technologies) The design preferences we had were essential to our component selection. Our research led WiVal to several paths of design choices. WiVal studied different versions of wireless systems and existing Valet System to settle on a design. WiVal took the path of RF technology and moved forward. The world of RF technology is an inexpensive and accessible world in which WiVal can begin its journey. Companies like Linx Technologies provide several components that will allow WiVal to use RF components that are compliant with FCC Standards and beneficial to a Valet company or restaurant that wants to enhance their customer experience. The components described in the following sections are all able to be purchased and tested by common citizens. These next few sections describe the technology that drives WiVal forward in a competitive market.

6.2 RF Transmitters The members of WiVal had a few options with the assortment of transmitters for this project. Initially we had intended to use the 900 MHz modules for the RF transmission because 900 MHz is the most flexible off all the FCC regulated frequencies. This permits any analog or wireless data signal transmission without restrictions on content and distance. However intense research led as to believe that it was an unstable frequency to operate on because of the popularity of the band within the RF spectrum making it crowded and the higher-level interferences cause by many products using this frequency.

6.2.1 RF Transmitter Selection After weeks of conversing, the 418 MHz frequency was chosen. Unlike the 900 MHz, this frequency is highly restricted, thereby making the wireless communication system less prone to interferences. The prices for the transmitters and receivers used at these frequencies are also considerably lower, 51! !

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as compared to those intended for use at 900 MHz. Since less output power is used, a longer transmission range is attained and battery life is prolonged. One wonderful attribute of this frequency is that unlike 900MHz which is restricted to the U.S, many countries worldwide have allocated this frequencies for wireless communication devices, in this manner making it possible for WiVal’s product to be sold overseas. On the other hand the main manufacture of interest was Linx Technologies; a company that supplies RF based chips for personal and commercial project. Linx Technologies was a clear choice from the beginning because their RF modules only necessitate an antenna, as compared to companies that require supplementary external RF components. We looked into the ES Series, HP-3 Series, LC Series, KH2 Series and LR Series which had very interesting applications.

6.2.1.1 ES Series RF Transmitter Excellent for transmitting analog and digital signals, this transmitter is brilliant for new ground-breaking designs. The ES Series is housed in a small package making it an exceptional choice for our portable receivers. In terms of performance, it was built on the latest advance structural design for noise protection and superiority. However its price tag is a little bit on the pricy side. The key features include: ! ! ! ! ! ! !

Low current consumption of 2.2mA Ultra-compact SMD package Supports FM / FSK modulation Wide bandwidth (20Hz to 28kHz) User power-down input of .45 VDC Low-voltage detect output 4dBm Power down current of 5.4nA

6.2.1.2 HP-3 Series RF Transmitter Considering that it is the most up-to-date of the HP Series transmitters, this transmitter is equipped with! a highly developed microprocessor controlled synthesized structural design. Enhanced developments analogous with other RF components also ensure reliable high performance wireless data transmission. Nevertheless, this complex chip allows for interference and decreased accuracy. According to www.Linxtechnologies.com, its features include: ! ! !

Transparent analog / digital interface Wide-range analog capability including audio (50Hz to 28kHz) Wide temperature range (-30°C to +85°C) 52!

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! ! ! !

No external RF components required Compatible with previous HP Series modules Power-down and CTS functions Wide supply range (2.8 to 13.0VDC)

6.2.1.3 LC Series Transmitter For the most part the Low cost RF transmitter is designed for basic wireless applications such as remote control and periodic data transfer. Fitted in a compact surface to mount package this chip offers high-quality performance for its size and cost. A drawback of the LC Series is the transmitter slower data transfer rate. According to www.Linxtechnologies.com, its features include: ! ! ! ! ! ! !

No external RF components required Ultra-low power consumption Stable SAW-based architecture Wide supply range (2.7-5.2VDC) Direct serial interface Low harmonics No production tuning (Linx Technologies)

6.2.1.4 KH-2 Series Transmitter The KH-2 Series is idyllically well-matched for highly protected applications such as keyless entry and security alarm systems. It is made up of a RF transmitter and an encoder. Having this combination satisfies our requirements for a suitable portable receiver. Equipped with ten tri-state address lines this chip offers superior security for wireless communication when combined with the KH2 Series receiver / decoder module. Its key features are: ! ! ! ! ! ! !

Low cost of $10 On-board encoder (Tx) / Decoder (Rx) 8 Parallel lines allow direct interface No external RF components required (except an antenna) Ultra-low power consumption Compact surface-mount package Stable SAW-based architecture

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6.2.1.5 LR Series Transmitter This particular transmitter, as its name implies is designed for long range wireless data transfer. It is capable of communication at data transfer rates of up to 10,000bps this supports Wival’s design of transmitting data as fast and reliable pace. It also has a transmitter modulation delay of a maximum of 30nS after it is turned on. The LR series transmitter which normally operates at 3VDC is an excellent choice for long battery life as a result of its low voltage requirement. Transmitting at a frequency of 418MHz allows this transmitter to pass FCC requirements. Another important parameter of this chip is that the transmitter was built using an architecture that delivers outstanding stability and exceptional sensitivity which allows this chip to have a low data input and power down input of .25VDC. Fabricated in a tiny carton, the transmitter employs FM/FSK modulation for analog and digital data respectively, allocating for much greater noise susceptibility and hence making it an excellent choice for our main station. According to Table 6.2.5 the important specifications are outlined as follows:

Table 6.2.5 Specifications of the LR Series Transmitter (With permission granted by Linx Technologies) 54! !

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The Linx HP-3 Series transmitter which allows for 8 parallel channels and up to 100 serial channels combined with a long rage of transmission was the group’s first choice however it was too big for architecture of the main station. The group’s next target was the Linx ES series transmitter which has a longer range and is smaller in size than the HP-3 series but higher power consumption as well as a heavy price tag. After months of deliberation we finally decided to go with the 418MHz Long Range modules series. Similar to the LC Series, this transmitter offers high-quality performance for its cost and size. This will be more than ever useful for fulfilling the group’s project goals. The LC Series interfaces with virtually any data source including microcontrollers and decoders, making it suitable for our application. The members of Wival chose this RF transmitter because the RF Module offers the essential tools to satisfy the requirements of the main station.

6.3 RF Receivers The component selection is a critical part of optimizing the receiver performance and achieving a good balance. There are more than a few important factors that have to be taken into deliberation when deciding on the ideal RF Receiver to use in implementing our data reception. With that in mind, the group came up with a series of identifiable challenges, and then found solutions and products to overcome them. The operating principles of these receivers are described in the following. 1. Cost: Since the members of WiVal’s group are responsible for footing the bill for this senior design project, it is very important that take all the necessary steps in minimizing the cost. This means that the RF receiver selected should be worth its value based on the performance ratings of various competitors. 2. Size: The size of the various components of this project pretty much defines whether or not WiVal is marketable. In today’s wireless age where size plays a major role in the use and sale of products, it is important that our portable receiver is as small as possible. This means that the group will have to select the smallest possible RF receiver that meets WiVal’s specification. 3. Sensitivity and noise level: The receiver sensitivity is responsible for determining the thermal noise level of the wireless communication system. Furthermore noise directly affects the overall system performance of a wireless communication system. As a result in the selection process of an RF receiver, it is essential that the group emphasizes the sensitivity and noise level of WiVal’s components. 4. Range: The ability to distinguish between different signal levels within a communication zone is a very important factor in the selection of an RF 55! !

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receiver. As mentioned in the research portion, one goal of the members of WiVal is to manufacture a portable receiver that can receive message efficiently. Therefore having a receiver with the capabilities of expanding its range will make this objective transpire.

6.3.1 RF Receiver Selection Choosing a RF Receiver to use for this project has been a very challenging ordeal. This is due to the fact that each receiver must meet strict performance criteria defined by the various standards of WiVal’s design, since a successful wireless design often depends on the ability to find the components that fulfill our design requirements. After exploring some manufacturers of such devices, the group looked into five major receivers.

6.3.1.1 The Microchip UHF rfRXD0420 Receiver Module The rfRXD0420 is an RF receiver module that can be used in applications such as Wireless remote command and control and security systems. Designed by a company that is known very well in the wireless communication world, this component those not dissatisfy the group. The rfRXD0420 has an extended RF receiver frequency range that covers both 300 MHz to 450 MHz and 800 MHz to 930 MHz.. According to www.Microchip.com, its features include: ! ! ! ! ! ! ! !

Has a fixed frequency at 315 MHz and 433.92 MHz Supports ASK or FSK digital modulation Has a signal rate of 4800 baud Receiver Sensitivity of -100dBm Wide supply range (2.5-5.5VDC) A satisfactory cost of $20 The IF Frequency range is selectable between 455 kHz to 21.4 MHz. supports a screw on antenna connection

6.3.1.2 LC Series Receiver The LC Series is a very basic RF receiver. It is compact, with a built in optimized SAW architecture for compromising efficiency. The LC Series RF receiver is capable of transferring data up to a distance of about 300 feet. Its key features are: ! !

Outstanding Sensitivity of -110dBm Supports Data Rates to 5,000bps 56!

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Low cost of $10 Operates at a voltage of 4.2VDC

6.3.1.3 LT Series Transceiver The LT Series transceiver is a bidirectional RF module. The transceiver is capable of generating a +10dBm into a 50-ohm load. It also has a representative sensitivity of -112dBm. Like the LR Series receiver this module is capable of transferring data at rates of up to 10,000bps. According to www.Linxtechnologies.com, its features include: ! ! ! ! ! !

Long Range Data transfer distances of up to 3,000 feet. Supports Data rates up to 10,000bps cost of $22 Wide supply voltage range (2.7-5.2VDC) Support a 260-470MHz band. Sensitivity of -112dBm.

6.3.1.4 LR Series Receiver Described as an ideal receiver for the wireless transfer of serial data and command information, This RF receiver has 5 to 10 times better reception range than its other counterparts produced by Linx Technologies. The LR series does this by having a center frequency accuracy of 50kHz and a noise bandwidth of 280kHz, which together supports Wival’s specifications and design for consistent receiver. It is housed in a tiny compatible SMD package with advanced synthesized architecture achieves an outstanding receiver sensitivity of 112dBm, a dynamic range of 80dB and a receiver gain of 16mVper dB. The RF receiver also Supports Data rates of up to 10,000bps at extended temperature capabilities of -40 to 70 degrees Celsius. The general specifications are outline in Table 6.3 below.

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Table 6.3 Specifications of the LR Series Receiver (With permission granted by Linx Technologies)

6.3.1.5 Radiotronix RCR-418-RPR Receiver The RCR-XXX-RP is designed for very low cost short-range wireless communication applications. With an ordinary person in mind, Radiotronix built a module that is very easy to use and implement in a design. The RF receiver module requires only a homemade wire antenna to operate. According to www.Radiotronics.com, its features include: ! ! !

Very low Cost of $4 Has a 3MHz receiving bandwidth Works with any LC or SAW based transmitter 58!

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! ! ! ! !

Needs only 5V to operate Has a 4.5mA current drain Small Size: 1.76” x .43” Has a signal rate of 4800 baud It can take up to 750mSec for the data output to become valid

Linx LC Series receivers were the most appropriate choice to allow for a quick and reliable design. Additionally, the compact low cost LC modules are the cheapest modules that Linx Technologies currently has to offer. However after reviewing the RF receivers above, the members of WiVal decided to use the LR Series receiver. This decision was mainly because we were already using the LR Series transmitter. Moreover is unique design and specifications shown in Table 6.3 completely met the group’s design specifications.

6.4 The Antennas The decision to determine which antenna to implement for the portable receiver was almost certainly challenging, since the group’s ambition was to use the smallest possible antennas without drastically affecting the performance. Even though WiVal’s portable receiver will work well with the loop and whip antennas, a helical antenna was chosen for its compactness and small size. The whip antenna would have allowed for a more competent outcome since it is Omni directional. However its long length makes it impossible to have on a very small device. The RH series from Linx Technologies was chosen. As its name says, reduced height helical whip antenna offers excellent performance despite its small size. Another attractive feature of this device is the ability to withstand a tough environment. According to www.Linxtechnologies.com, its features include: ! ! ! ! ! ! !

Bandwidth of approximately 80 MHz Omni-directional pattern Approximately 2 inches long and .33 inches in diameter Fully weatherized Rugged & damage-resistant Impedance of 50 ohms Connector RP-SMA or SMA

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Figure 6.3 a RH series whip antenna (With permission granted from Linx Technologies) An antenna plays a crucial role in determining the overall performance of a wireless communication system, because both the performance and range of transmission depend heavily on the antenna. It was therefore in our best interest to spend a lot of time on this piece of the main station. After intense research into the characteristics and advantages of each antenna design, the permanent mount PW Series 1/4-wave whip antenna from Linx Technologies was selected. As shown in Figure 6.4 below, It is a lengthy and rigid antenna. One of most important reasons why we chose this antenna for the main station is because of its specifications and other performance related features. According to www.Linxtechnologies.com, its features include: ! ! ! ! ! ! !

Low cost of $ 7 Outstanding design based on its small size Omni-directional pattern Wide bandwidth of 80 MHz Flexible main shaft as shown in Figure 5.4 below Rugged & weatherized Integral 8½-inch RG-174 coax cable

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Figure 6.4 a permanent mount PW Series 1/4-wave whip antenna (With permission granted from Linx Technologies) With that in mind the decision won’t be finalized until we start the actual testing of the group’s wireless messaging system to determine which antennas provides the best overall performance.

6.5 Encoders After some research it became clear that the main criterion in selecting the encoder was to look for an encoder that was simple but small enough to implement a push button function. During the design of this project, the team members took every measure to ensure that the group picks the most compatible and smallest encoders available on the market. With this in mind, one of the options we considered to use was the Holtek HT640 encoder from Holtek Semiconductor Inc. ! ! !

Low cost of $4 Uses a eight bit binary address Uses a low voltage of 2.4V to 12V 61!

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! ! ! ! !

Easily compatible with RF based modules Excellent choice for future modification because of its flexibility Has a low standby current of .1 to 1 µA Comes in a Standard 20-pin PDIP package Very easy to use with no programming necessary.

6.6 Decoders In view of the fact that the group had selected the encoder from Holtek Semiconductor Inc, the members decided to use a companion decoder which is the Holtek HT658 decoder. One of the advantages of this combination is the fact that we can cheaply accomplish the task of building dependable push button pagers. The group decided to narrow the selectable options down by choosing the simplest device possible. ! ! ! ! ! ! !

Has the Capability to decode 18 bits of information Can be paired with the HT640 encoder for future modifications compares the signal and has a valid transmission indicator Uses a low voltage of 2.4V to 12V Has a low standby current of .1 to 1 µA Comes in a Standard 20-pin PDIP package Low cost of $4

6.7.1 Display Initially, the group desired an LCD screen for the purposes of outputting information to the user. The LCD screen would have to be small enough to fit on the handheld portable receiving units, while at the same time it would have to be large enough to be able to read, even if the protection over the screen got dirty or scratched. Additionally, the screen would ideally be lit, as many businesses that will use the WiVal system may still offer valet services after night has fallen. In researching display options, however, the group discovered that pre-constructed LCD screens for handheld devices on the scale of the portable receiver of the WiVal system are, for all intents and purposes, completely non-existent. The next preference, then, was to custom order LCD screens for the devices that make up the WiVal system. The advantage of this approach would be that the group would be able to have the LCD screen manufactured to the exact dimensions necessary, without having excess screen, or a screen that was too small. Additionally, the group would be able to specify the desired resolution of the LCD screen, allowing the resolution to remain high enough for the required details, while still remaining low enough to be manageable. The major downside to this approach was that the cost of custom ordering LCD screens is prohibitively high. Though it is not so high as to bankrupt the group if they chose 62! !

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to custom order, the price is still high enough that the cost of the screens would far outweigh any benefit of having an LCD screen over the much cheaper alternatives. In the end, the group decided that what really mattered to the success of the WiVal system was to keep costs at a minimum, so that the system could be kept as affordable as possible. To this end, the group decided on using seven segment LEDs to simply display the number of the car which is ready. The LEDs are low-power, which will aid in their being powered by a battery. Additionally, the LEDs can display digits 0-9, so with two LEDs, up to 100 cars can be uniquely identified, having numbers 00-99. The LEDs also have the advantage of producing their own light, which will guarantee that the display will be visible even in low-light conditions.

6.8 Microcontroller Several microcontrollers were considered for use in the WiVal system. The microcontrollers under consideration were: the Texas Instruments MSP430 family, the Parallax Inc. BASIC Stamp, and the PIC® family. The Texas Instruments MSP430 family were the first microcontrollers under consideration. One of the major benefits of the MSP430 is Texas Instrument’s ez430 line of products. This series of development kits allows for easy USB connection of the devices for the purposes of programming and testing. The devices utilize C programming language for instructions, which has the benefit of familiarity to the WiVal group. The chip of most interest, the MSP430-F2012, is very low cost, at only $10 for three development boards. The boards themselves are small enough that they could themselves be used in the final product, if necessary. The MSP430-F2012 has 2 KB of program storage, and 128 B of RAM. This should more than suffice for the purposes of the WiVal, and is considerably more than several of the other microcontrollers. The power consumption of the MSP430-F2012 is very low. It is designed to operate at between 1.8 and 3.6 volts, and even in active mode, it draws only a miniscule 220"A. The next microcontroller looked at was the BASIC Stamp. The BASIC Stamp 1 also has a development kit, though it is a bit more cumbersome than the ez430. Additionally, each Stamp costs $29.00. The Stamps tend to be a bit on the large side, especially as they seem primarily designed for through-board soldering. The BASIC Stamp 1 has only 256 B for the program, or about enough for 80 instructions, and only 16 B of RAM. It runs, obviously, on a form of BASIC, known as PBASIC, which is less familiar to the group than C. It runs on 5 to 15 volts, and in active mode, draws a whopping 1mA of current, even when running at only 5V.

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The last microcontroller considered was the Microchip Technology Inc. PIC32, specifically the MX320. The PIC32 MX320 costs only $4.25, though that is for only a chip, with no development board. Sadly, the PIC line does not have the option of purchasing with a development board. The upside is that when installing, one needs only space for the chip, not an entire board. The chip has an impressive 32KB of storage for the program, and roughly 8KB of RAM. It, like the ez430, uses C programming language as it’s driving force. It runs on 2.3-3.6 volts, though no reliable information could be found, anywhere, regarding the standard current draw for the PIC32 MX320. In the end, the Texas Instruments ez430-F2012 was chosen for both the main station and for the portable receiver, for several reasons. First, it would is probably the easiest in terms of development, both because if its development kits and because of the use of C programming language. Also, at 3 for $10, it is easily the cheapest of the three microcontrollers. And though it lacks the storage of the PIC32 series, it was felt that the extra power would not be greatly beneficial to the WiVal’s operation. It was decided that both the main station and the portable receiver should have the same microcontroller for ease of implementation, and to reduce the costs of replacement, as often discounts are offered for purchasing in bluk..

6.8.1 Programming The software in the WiVal system must be able to store a list of cars to be retrieved, as well as be able to quickly process inputs, so as not to miss any signals. Several different programming languages were available for designing the software to be used in the WiVal system. Of the variety of languages available, Java, C, BASIC, and assembly were all looked into, as these were the most common languages to be found in use with commercially available microprocessors. Java was the first programming language considered for use in the WiVal system. Java is a powerful, object-oriented programming language, which would more than meet the needs of the WiVal system. However, Java is far more powerful than is really required by the WiVal system. Ultimately, Java would likely require more resources, in the way of storage space and processing time, than is necessary to run a relatively simple system. Additionally, Java is not as familiar to the group as is desired for this project. C was the second programming language considered for use in the WiVal system. C is a very commonly used language, and could certainly handle the task of running the WiVal system. Though not object-oriented, C definitely has the capability to run all the features required in the most basic design of the WiVal system. It runs fast, and yet it is of high enough level that it is easy to understand. It is also very familiar to the group, and the support for it, both in the 64! !

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library and online, is vast. Overall, C is most likely the programming language of choice, if available to the project. BASIC was the third programming language considered for use in the WiVal system. BASIC is a very easy language to understand, and could most likely handle the task of running the WiVal system. However, BASIC is not quite as familiar to the group as is desired for this project. Additionally, it is unknown if BASIC has the capacity to handle any additional features that the group may desire to add into the design at a later point in time. Assembly was the final programming language considered for use in the WiVal system. As the lowest level of the programming languages considered, it would take up very little space, and would run very fast. However, it could potentially be extremely difficult to get some of the more advanced features of the WiVal system to work in assembly. Additionally, as different hardware setups use different versions of assembly, the group may or may not be familiar with the programming language, depending on which microprocessor is used in the WiVal system. In the end, C was chosen as the language of choice for the WiVal system. It is powerful enough to suit the needs of the project without drawing power for too many unnecessary additions. It is also very familiar to the group, and the variety of information about it online and in print all but guarantees that any stumbling blocks encountered will be able to be overcome with but a little research on the group‘s part.

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Final Design 7.1 Final Design The strategy devised by WiVal’s group was to work together on every aspect of the project. Each group member is responsible to know and understand each component and work together to achieve the desired outcome, but some tasks were distributed such as purchasing, planning, designing, programming and gaining permissions letters. The project will be done in different stages. A major and critical part of our design was the WiVal Main Base Unit processor and as a result WiVal took several steps in determining which one of the chips will be the most appropriate for our project. In determining the chips to use for our project we looked at several factors such as the cost of the chip, the accuracy and the type of programming involved.

7.1.1 The Main Station A properly designed RF main station structure is an important component of the group’s wireless communication system. It is therefore imperative that the members of WiVal use the information gathered from the research and component selection to create a very sound and stable wireless system that meets the goals of WiVal. The design of the main station is divided into two major components, mainly the Transmitter and Receiver. Both the RF transmitter and RF receiver will be connected to the same microcontroller and LED. However, this portion of the design will focus mainly on the RF transmitter and RF receiver. The design for the microcontroller and LED will be covered in detail in the subsequent sections. After some consideration it was decided that the easiest way would be to start with the RF transmitter.

7.1.2 The RF Transmitter Once the decision had been made to use the LR RF transmitter from Linx Technologies, the final design of the main station had begun. This component is an important feature because it allows for the main station to send on the spot commands to each portable receiver without the need for a valet clerk to have to travel to it to receive the previously transmitted signal from the pushbutton pager. Also, WiVal’s design relies enormously on the main stations ability to consistently transmit data to the portable receivers. 66! !

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7.1.2.1 The RF Transmitter Connection Figure 7.1 in below and Table 7.1 in the table of contents show the Pin assignment and description respectively. First, Pin 1, 3 and 6 are set to analog ground. The transmitter primarily receives input data serially from the microcontroller which connects through the Pin labeled PDN and then transmits this data on a selected channel through the antenna labeled ANT. The microcontroller is the master of all activities in the main station. It reads in an identification number when receiving an input data. This allows the Microcontroller to select the parallel channel. Once this happens, the data is then processed into a data packet which is sent to the transmitter. The transmitter then processes data, one byte at a time based on the desired signal rate of the RF Transmitter. At the same time as this occurs, the transmitter processes the data packet and then transmits this data onto a selected channel through the antenna labeled Pin ANT. Pin 2 is the Digital Data Output (Data) which is responsible for outputting demodulated digital data. Also, there is the Level Adjust (LADJ) Pin which is in charge of adjusting the output power of the RF transmitter by placing a resistor between Pin 7 and LADJ. However Pin 7 is the Voltage Supply, which is designed to normally use 3VDC in order to function steadily. Finally the data is broadcasted through air via Pin 5, where it is picked up by a friendly portable receiver.

7.1.3 The RF Receiver The demands for higher reception data rate and better quality of wireless communication systems are put forward in determining the overall performance of a RF receiver. To simplify the overall design as much as possible the members of WiVal decided to target system parameters for the receiver portion to be designed for the main station by using the companion LR Series RF receiver. The RF Receiver is designed to work in hand with the RF transmitter for it is believed that this combination will be particularly useful to put into operation a successful main station.

7.1.3.1 The RF Receiver Connection Starting from the top, Pin 1 through 3 and 9 through 14 has no connections. Next Pin 4 and 15 are both set to analog ground. Subsequently, the RF receiver takes in incoming data on a selected channel through the antenna tagged Pin ANT and outputs it serially to the Microcontroller which connects through Pin PDN. The transmitter’s Power Down (PDN) Pin can also be used to put the transmitter on and off. Pin 5, is the Voltage Supply, which is designed to normally use 3VDC in order to function steadily. The receiver’s Received Signal Strength Indicator 67! !

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(RSSI) Pin serves as a power regulator. It also outputs a voltage proportional to the incoming signal strength of transmitted data. The next Pin is the Digital Data Output (Data) which is responsible for outputting demodulated digital data. Finally, Pin 9 is where the antenna is going to be connected to receive data from the pushbutton pagers. A description of the pin layout and its functions are also described in Figure 7.1 displayed below and Table 6.2.5 in the table of contents respectively.

7.1.4 The RF Transmitter and RF Receiver Combined To enhance the circuitry and system performance of the main station, the members of WiVal focused team efforts on improving the transmission and reception of data through the scaling of device dimensions and specifications. The main goal is to establish a 2-way wireless connection for the main station by connecting the RF transmitter and the RF Receiver with a microcontroller. A LED and an antenna will also be connected to finalize the design of the main station. The LED display will be used at the main station by an attendant to observe which car has been requested to be retrieved. The LED will receive its inputs from the base stations microcontroller. The signals that the microcontroller receives from the pushbutton pager will illuminate the LED if the signal is verified as a signal from the main station. On the other hand the LED and the Microcontroller will be discussed in details in the later sections. A transceiver will be made by placing the RF transmitter and RF receiver on each side of the Microcontroller this is shown in Figure 7.1. The team’s wireless communication design project will send a data envelope to all the Portable receivers within the group’s desired range by means of an antenna delivering data through free space. Each transmitted data packet contains an ID number of the transmitter. The transmitter then uses a microcontroller to read and control the functions of the main station. The antenna would receive a communication signal from the pushbutton pager. This signal would then be passed to the microcontroller, to be recognized from the list of assigned pushbutton pager numbers. The output from the main station goes to a microcontroller, where appropriate interpretations are made to determine what action to take. The results are then sent in the direction of the transmitter to wirelessly send data en route for the Portable receivers.

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Figure 7.1 a schematic of the operations of the main station

7.1.4.1 The Main Station Antenna The efficient transmission and receiving of RF communication signals in free space necessitate the size of antennas to be analogous with their wavelengths and power output. Because the RF transmitter and RF receiver modules are coming together to form a transceiver, it is very important that the group takes all possible measures to decrease the size, cost and components selection of the design for the main station. One such valuable action that can be taken is to 69! !

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share a single antenna as compared to using two separate ones. This can be accomplishing by using a commercially manufactured antenna switch as shown in Figure 7.2. However a range test with different configurations of antenna length and types selected for use in this project will need to be conducted in order to find the most effective antenna for this system and whether or not a antenna switch is need. Once this occurs, the antenna will be attached to the main station so as to effectively transmit data to the portable receivers and receive signals from the pushbutton pagers. For now we are going to use the permanent mount PW Series 1/4-wave whip antenna from Linx Technologies. The team is confident that if this module were to be used in the main station application, we will have a functional wireless transmission tower.

Figure 7.2 a basic antenna switch (With permission granted by Linx Technologies)

7.1.4.2 The Main Station Voltage There are a few main deliberations which are related to the voltage, that expand the range and efficiency of the main station. Foremost, the higher the input voltage, the stronger the transmission and receiving signal strength will be. In view of the fact that both the RF receiver and RF transmitter do not have a built in regulator, It is therefore important the group builds a voltage supply filter that can regulate the voltage of the RF receiver, RF transmitter and the Microcontroller to maintain the voltage of the main station so as to increase the efficiency of the main station. Secondly, Power supply noise can affect the transmitter and receiver modulation it is therefore suggested by Linx 70! !

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Technologies to use a low-pass RC filter between the VCC Pin and the Linx modules to reduce the high frequency noise. Displayed in Figure 7.3 is a basic voltage supply filter. In Figure 6.3 a 10! resistor is placed in series with the voltage supply followed by a10"F tantalum capacitor from VCC to ground.

Figure 7.3 a basic supply filter (With permission granted by Linx Technologies)

7.2 The Portable Receiver The portable receiver consists of a LED and a Microcontroller connected to the RF receiver module to receive transmitted data from the main station. Unlike the main station, the portable receiver is only participating in a one way transmission system. With this known fact, this portion of the report will focus entirely on the operation of only the RF receiver in the construction of the portable receiver. The target system parameters for the portable receiver to be designed are put forward the growing demands of the mobile telecommunication and Internet services in developed and emerging countries. This demand is what put the members of WiVal in position to create a small and inexpensive technologically advance portable receiver which is the central point of the group’s wireless communication system.

7.2.1 The Portable Receiver Connection There will be a single receiver module that will be responsible for the reception of transmitted data from the main station as shown in figure 7.4. Starting from the top left corner of the RF receiver, there are several Pins with no connections. These Pins are 1 through 3 and 9 through 14. Next Pin 4 and 15 are both set to analog ground. Consequently, the RF receiver takes in incoming data on a selected channel through the antenna tagged Pin ANT and outputs it serially to the Microcontroller which connects through Pin PDN. The microcontroller is 71! !

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responsible for all the indirect communication between the RF receiver, the main station the LED and the vibrator. The RF receiver will only receive data signals from the main station by first authenticating the main stations identification code. Each time a message is sent to the portable receiver, the main stations identification code will be sent along with the data packet. This is done so that the portable receiver knows that every sent message is from the main station and not a phony transmitter. This allows the Microcontroller to select the parallel channel. Once this happens, the data is then processed into a data packet which is sent to the RF receiver. The RF transmitter will use an incoming voltage 3VDC in order to function steadily. The receiver’s Received Signal Strength Indicator (RSSI) Pin which is Pin 7 serves as a power regulator. It also outputs a voltage proportional to the incoming signal strength of transmitted data. The next Pin is the Digital Data Output (Data) which is responsible for outputting demodulated digital data. Finally, Pin 9 is where the RH series antenna from Linx Technologies is going to be connected to receive data from the main station. A description of the Pin layout and its functions are also described in Figure 7.2.1 in the table of figures and Table 7.2.1 in the table of contents respectively.

Figure 7.4 a schematic of the portable receiver (Redrawn with permission granted by Linx Technologies) 72! !

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7.3 The Pushbutton Pagers The push button pager is the less complicated portion of the wireless communication system. It is made up of an encoder and a decoder. The goal of the members of WiVal is to create a prototype of the Keyfob transmitter from Linx Technologies that is as lightweight as possible, very small and easy for the individual to use and carry. As with other commercially manufactured products, it will be well-organized and dependable. It will also have capability of the Keyfob to stay on batteries for day and maybe years at a time without a replacement battery needed. As mentioned before, the encoder is the device that corresponds to a message sent from the main station. It does this by taking in incoming data from the main station along with a little security signal that verifies whether the inward bound data is being sent from the main station. Once this occurs, a data signal is sent back to the main station to validate the reception of data. Finally the data is interpreted by the encoder. The decoder on the other hand does the exact opposite. This pushbutton pager may also be used in combination with a RF transmitter for future modifications to the wireless communication system.

7.3.1 The Pushbutton Pager Connection Figure 7.5 shows a schematic of WiVal’s pushbutton pager. Starting with the bottom right hand side of the encoder, Pins 13-22 are Input Pins for address A0A9 settings. Pins 1-7 on the top right, are Input pins for data D0-D7 settings. Both Pins 1-7 and 13-22 both have the options to be externally set to VDD or VSS. When a transmission signal is implemented from the pushbutton pager, the encoder scans and transmits the data serially to A0 to A9 and then to D0 to D7.At the very top right corner is the VDD Pin, which is powered by a dry cell with a maximum input of 12V.On the opposite end is the VSS which is the connection to ground. The encoder is also equipped with an oscillator frequency input and output at Pin 10 and 11 respectively. The transmission enable lines (TE) indicated as Pin 9 begins a three word transmission cycle when it set high. This in turn starts the transmission process of the encoder as shown in figure 4.3 above. Finally, the essential Pin that connects to the decoder to establish the pushbutton pager is Pin 8, marked as DOUT. DOUT is responsible for transmitting serial data out of the encoder. As shown in Figure 6.5, the DOUT Pin connects directly to the DIN Pin on the decoder. Both the encoder and decoder have ten address lines each that have to be equivalent in order for the main station and pushbutton pagers to talk to each other accurately and effectively. The decoder will receive data transmitted by the encoder through Pin DIN. The encoder will then read between the lines of the first 10 bits of the code as address and then read through the remaining bits of the code as data. Next, the decoder will check the received address code. Once the received address codes shows up as exactly the one sent by the decoder’s local address, the 8 bits of 73! !

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data are decoded to activate the output pins, and the VT Pin is set high to indicate a valid transmission. A signal on the DIN Pin then activates the oscillator, which in turns decodes the incoming address and data. The decoders will check the received address twice continuously. If all the received address codes match the contents of the decoder’s local address, the 8 bits of data are decoded to activate the output pins, and the VT pin is set high to indicate a valid transmission. (www.Linx Technologies.com).once this occurs a signal from the pushbutton pager will be sent to main station.

Figure 7.5 the schematic of WiVal’s pushbutton pager

7.4 PCB The main requirements in determining what kind of PCB to use for the entire project taken as a whole were price, size and the weight of the component. Size is an important factor in PCB selection for WiVal, because of the handheld nature of the portable receiver and the pushbutton pagers. The success of WiVal depends a lot on the size and weight of the components.! After months of deliberation by team members we decided to order the PCB as a Standard Spec, 74! !

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as compared to a Custom built Spec board. This decision was based on the fact that a lot of components need to be placed in a restricted gap in order to work properly. Take for example, the mounting of the antennas which require special care and placement on the PCB. The antennas need to be turned away from the digital component as well as power the power sources, to prevent various interferences. With this in mind, the antennas will be placed on the very ends of the PCB so as to avoid any issues. Also having a standard PCB makes it easier for the members of WiVal to test and modify component designs. It is very important that the group separates the analog and power component of the design, to prevent any electromagnetic damages to the various components. However because the optimization for size is a very important factor in WiVal’s design, the group has decided to have the PCB for the pushbutton pagers and portables receivers custom built and soldered for the final development and presentation. This conclusion is due to the need to minimize size but also decrease the chances of one accidentally soldering wrong parts or damaging components on the board. There are many factors that will influence the final design and size of the PCB, however most of these factors will not be faced and determine until we begin the initial phase in the next senior design class.

7.5 Microcontroller The line supply line on the Texas Instruments ez430-F2012 board will be connected to the voltage from the power supply, while the line ground line will be connected to ground. Four digital lines from the Texas Instruments ez430F2012 will be used to power the LED display. Since only one line can be powered at a time, the 14 lines that will control the LEDs will each be tied to a latch. When power is sent down one line, through a diode to prevent analog feedback into the digital system, it will activate the latch, and the LED will turn on. The Texas Instruments ez430-F2012 will then turn on all the required LEDs in turn. To reset, one of the two remaining lines from the decoder will activate a transistor tied to ground, again through a diode, in parallel with the latches and LEDs. When the transistor is activated, the current through the transistor and accompanying resistor will drop the current through the latches below that which is necessary to maintain the latch, thus shutting off all the LEDs until the next signal is sent. The final line from the decoder will be available for any additional function deemed necessary. Three digital input lines will be used for the three buttons to add their input. An analog input line will be used to take in a signal from the receiver, and in the main base, an analog output line will be used to send a signal to the transmitter. An additional analog output line will be used to send a signal to the speaker, to alert the user that a new car has been! added to the list. !

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The program will need to keep track of which pagers have been activated. In order to do this, a bi-directional linked list will be used. The linked list will be treated as a ring, with ten slots. After ten cars have been added to the system, any additional cars will be written over the previous cars, starting with the oldest. It is believed that ten will be enough cars to ensure that the valet service using the Wival system does not fall behind and drop cars that have not yet been returned. Several components will be necessary for the software. A complete listing of all functions is found in figure 7.2.1-1. First of all, the main program will be in a never ending while-loop, as the program is meant to continue running for as long as power is supplied. The program will then first check for a signal with the CheckSignal function. If a signal is found, it will then send the signal to the DecodeSignal function. The program will then call the AddCar function to add a car to the database, and then the AlertUser function will be called, to send a signal to the speaker to let the user know that a new car is ready. In the main base, after the AlertUser function is called, the EncodeSignal function will be called to translate the car number into a signal to rebroadcast to the portable receiver by means of the SendSignal function. In both the main base and the portable receiver, the loop will then restart. If no signal is found with the CheckSignal function, then the main function will call the CheckKeys function, to see if a button has been pressed. If it finds one, it will first determine if the key has just been pressed, or if it has been held down since the last time the function was called. If it determines that the key has been held down, the main program does nothing. If it determines that the key has just been pressed, the main program will then call a function based on which key it was that was pressed. If the forward button has been pressed, the program will call the ClearLED function to clear the display. It will then advance to the next car after the currently selected car. Then, the ToLED function will be called, to output the requested car number to the display, by means of the sub-functions OneOut, TwoOut, etc. If, however, the backward button has been pressed, the program will call the ClearLED function to clear the display. It will then move to the previous car before the currently selected car. Then, the ToLED function will be called, to output the requested car number to the display, by means of the sub-functions OneOut, TwoOut, etc. Finally, if the “latest” button is pressed, the program will call the ClearLED function clear the display. It will then shift the data to look at the most recent car added. Then, the ToLED function will be called, to output the requested car number to the display, by means of the sub-functions OneOut, TwoOut, etc. After the ToLED function has been called, the program will return to the main loop.

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Function

CheckSignal

DecodeSignal

Inputs

int*

int*

Returns

Purpose

int

Takes in an array to store a signal. After the signal has been stored, it returns 1 to the main program to indicate success.

int

Takes in an array containing the stored signal. After the signal has been decoded, it returns the car number to the main program.

AddCar

struct sCarData*, int

int

Takes in pRecentCar pointer, then places the car number into the next space in the ring, and updates the pRecentCar pointer. It then returns 1 to indicate success.

AlertUser

void

void

Sends an analog signal out to the speaker to alert the user of a new car arrival.

int

Sends a digital signal out to the clear line, in order to clear the LEDs for display of a new car number.

void

Takes in an integer number, then calls the ___Out functions to output it to the correct LEDs on the display.

void

Sends a signal out to the LEDs corresponding to the number each particular function is supposed to call.

ClearLED

ToLED

OneOut,TwoOut, etc

void

int

void

CheckKeys

void

int

Checks which key has been pressed, if any, and returns an integer to the user corresponding to that particular key.

EncodeSignal

int

int*

Takes in an integer number, then stores it in an integer array as a signal to be output.

void

Takes in a signal, in the form of an integer array, then sends it as an analog output to the transmitter.

SendSignal

int*

Figure 7.2.1-1 Table showing the inputs and purposes of each function in the WiVal system.

Several variables will be used in the program, in order for it to work properly. A structure called sCarData will be used to form the double linked list ring. The structure will consist of an integer variable called iCar, to hold the number of a car. The sCarData structure will also have two pointers. The pointer pNext will point to the next sCarData structure, whereas the pointer pPrev will point to the 77! !

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previous sCarData structure. A visualization of the sCarData structure is shown in figure 7.2.1-2. struct!sCarData int!iCar struct!sCarData*!pNext struct!sCarData*!pPrev

! Figure 7.2.1-2 Structure information for the sCarData structure. !

Additionally, two pointers accessible by the main program will be necessary. One, pCurrentCar will point at the car currently displayed on the LED display. Another, pRecentCar will point to the last car added to the ring. Additionally, a structure to hold each signal will be necessary. This will be an array of integers, each spot in the array holding one small piece of the signal.

7.7 Weatherproof Casing The weather proof casing choice WiVal is settling on is a PVC plastic that is sold through TAP Plastics. This material appears to be very trusted as it has a long list of properties including chemical inertness, water resistance, corrosion resistance, weather resistance, high strength-to-weight ratio, thermal insulation, and electrical insulation. The dimensions of sheets can be ordered to accommodate all sizes. This would be an excellent material for the insulating of different electrical components inside of the WiVal System and aid in shock/static resistance. Bonding the different sides of the PVC could likely be done using plastic cements or epoxies. These plastics will specifically be used for the Portable Receiver and the Main Base Unit. The Push Button Pager will be purchased through Linx Technologies and has a protective unit that is shown in figure 5.11. These pager casings are also strong for enough for rugged use and normal wear and tear. The Linx Technologies Key Fob can withstand cold weather down to 25 degrees. This low mark in temperature is the goal WiVal has in making the weatherproof casing as good as possible.

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Design Summary 8.1 The RF Transmitter Connection Figure 7.1 shown below and Table 7.2.1 in the table of contents show the Pin assignment and description respectively. First, Pin 1, 3 and 6 are set to analog ground. The transmitter primarily receives input data serially from the microcontroller which connects through the Pin labeled PDN and then transmits this data on a selected channel through the antenna labeled ANT. The microcontroller is the master of all activities in the main station. It reads in an identification number when receiving an input data. This allows the Microcontroller to select the parallel channel. Once this happens, the data is then processed into a data packet which is sent to the transmitter. The transmitter then processes data, one byte at a time based on the desired signal rate of the RF Transmitter. At the same time as this occurs, the transmitter processes the data packet and then transmits this data onto a selected channel through the antenna labeled Pin ANT. Pin 2 is the Digital Data Output (Data) which is responsible for outputting demodulated digital data. Also, there is the Level Adjust (LADJ) Pin which is in charge of adjusting the output power of the RF transmitter by placing a resistor between Pin 7 and LADJ. However Pin 7 is the Voltage Supply, which is designed to normally use 3VDC in order to function steadily. Finally the data is broadcasted through air via Pin 5, where it is picked up by a friendly portable receiver.

8.2 The RF Receiver Connection Starting from the top, Pin 1 through 3 and 9 through 14 has no connections. Next Pin 4 and 15 are both set to analog ground. Subsequently, the RF receiver takes in incoming data on a selected channel through the antenna tagged Pin ANT and outputs it serially to the Microcontroller which connects through Pin PDN. The transmitter’s Power Down (PDN) Pin can also be used to put the transmitter on and off. Pin 5, is the Voltage Supply, which is designed to normally use 3VDC in order to function steadily. The receiver’s Received Signal Strength Indicator (RSSI) Pin serves as a power regulator. It also outputs a voltage proportional to the incoming signal strength of transmitted data. The next Pin is the Digital Data Output (Data) which is responsible for outputting demodulated digital data. Finally, Pin 9 is where the antenna is going to be connected to receive data from the pushbutton pagers. A description of the pin layout and its functions are also described in Figure 7.1 displayed below and Table 7.1 in the table of contents respectively.

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8.3 The RF Transmitter and RF Receiver Combined To enhance the circuitry and system performance of the main station, the members of WiVal focused team efforts on improving the transmission and reception of data through the scaling of device dimensions and specifications. The main goal is to establish a 2-way wireless connection for the main station by connecting the RF transmitter and the RF Receiver with a microcontroller. A LED and an antenna will also be connected to finalize the design of the main station. The LED display will be used at the main station by an attendant to observe which car has been requested to be retrieved. The LED will receive its inputs from the base stations microcontroller. The signals that the microcontroller receives from the pushbutton pager will illuminate the LED if the signal is verified as a signal from the main station. On the other hand the LED and the Microcontroller will be discussed in details in the later sections. A transceiver will be made by placing the RF transmitter and RF receiver on each side of the Microcontroller this is shown in Figure 6.1. The team’s wireless communication design project will send a data envelope to all the Portable receivers within the group’s desired range by means of an antenna delivering data through free space. Each transmitted data packet contains an ID number of the transmitter. The transmitter then uses a microcontroller to read and control the functions of the main station. The antenna would receive a communication signal from the pushbutton pager. This signal would then be passed to the microcontroller, to be recognized from the list of assigned pushbutton pager numbers. The output from the main station goes to a microcontroller, where appropriate interpretations are made to determine what action to take. The results are then sent in the direction of the transmitter to wirelessly send data en route for the Portable receivers.

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Figure 7.1 a schematic of the operations of the main station

8.3.1 The Portable Receiver Connection There will be a single receiver module that will be responsible for the reception of transmitted data from the main station as shown in figure 7.4. Starting from the top left corner of the RF receiver, there are several Pins with no connections. These Pins are 1 through 3 and 9 through 14. Next Pin 4 and 15 are both set to analog ground. Consequently, the RF receiver takes in incoming data on a selected channel through the antenna tagged Pin ANT and outputs it serially to the Microcontroller which connects through Pin PDN. The microcontroller is responsible for all the indirect communication between the RF receiver, the main station the LED and the vibrator. The RF receiver will only receive data signals from the main station by first authenticating the main stations identification code. Each time a message is sent to the portable receiver, the main stations 81! !

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identification code will be sent along with the data packet. This is done so that the portable receiver knows that every sent message is from the main station and not a phony transmitter. This allows the Microcontroller to select the parallel channel. Once this happens, the data is then processed into a data packet which is sent to the RF receiver. The RF transmitter will use an incoming voltage 3VDC in order to function steadily. The receiver’s Received Signal Strength Indicator (RSSI) Pin which is Pin 7 serves as a power regulator. It also outputs a voltage proportional to the incoming signal strength of transmitted data. The next Pin is the Digital Data Output (Data) which is responsible for outputting demodulated digital data. Finally, Pin 9 is where the RH series antenna from Linx Technologies is going to be connected to receive data from the main station. A description of the Pin layout and its functions are also described in Figure 7.1 in the table of figures and Table 7.1 in the table of contents respectively.

Figure 7.4 a schematic of the portable receiver (Redrawn with permission granted by Linx Technologies)

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8.3.2 The Pushbutton Pager Connection Figure 7.5 shows a schematic of WiVal’s pushbutton pager. Starting with the bottom right hand side of the encoder, Pins 13-22 are Input Pins for address A0A9 settings. Pins 1-7 on the top right, are Input pins for data D0-D7 settings. Both Pins 1-7 and 13-22 both have the options to be externally set to VDD or VSS. When a transmission signal is implemented from the pushbutton pager, the encoder scans and transmits the data serially to A0 to A9 and then to D0 to D7.At the very top right corner is the VDD Pin, which is powered by a dry cell with a maximum input of 12V.On the opposite end is the VSS which is the connection to ground. The encoder is also equipped with an oscillator frequency input and output at Pin 10 and 11 respectively. The transmission enable lines (TE) indicated as Pin 9 begins a three word transmission cycle when it set high. This in turn starts the transmission process of the encoder as shown in figure 4.3 above. Finally, the essential Pin that connects to the decoder to establish the pushbutton pager is Pin 8, marked as DOUT. DOUT is responsible for transmitting serial data out of the encoder. As shown in Figure 6.5, the DOUT Pin connects directly to the DIN Pin on the decoder. Both the encoder and decoder have ten address lines each that have to be equivalent in order for the main station and pushbutton pagers to talk to each other accurately and effectively. The decoder will receive data transmitted by the encoder through Pin DIN. The encoder will then read between the lines of the first 10 bits of the code as address and then read through the remaining bits of the code as data. Next, the decoder will check the received address code. Once the received address codes shows up as exactly the one sent by the decoder’s local address, the 8 bits of data are decoded to activate the output pins, and the VT Pin is set high to indicate a valid transmission. A signal on the DIN Pin then activates the oscillator, which in turns decodes the incoming address and data. The decoders will check the received address twice continuously. If all the received address codes match the contents of the decoder’s local address, the 8 bits of data are decoded to activate the output pins, and the VT pin is set high to indicate a valid transmission. (www.Linx Technologies.com).once this occurs a signal from the pushbutton pager will be sent to main station.

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Figure 7.5 the schematic of WiVal’s pushbutton pager

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Testing 9.1 Testing Introduction In the world Electrical and Computer engineering, integration and testing is one of the most overlooked functions. Quite simply, the companies and organizations that practice the rules of allocating time for testing are the ones that are significantly more successful than the ones that do not. As such, it is highly unlikely to be a successful Engineering project without extensive testing and correcting of various chinks and bugs. It was decided that the product should have an extensive testing phase and given significant time before its completion date. Testing is always a fairly large concern for Engineering and wireless projects, and the testing phase of this project is expected to be a major role in the success of WiVal. The WiVal system will initially have the components and individual systems tested. Then, the systems will be connected together until all of the systems function as a whole. Finally, the components will be mounted inside their respective weatherproof casings. When WiVal is assembled, it will undergo a successful transfer of information from the customer’s Push Button Pager through the wireless system in range and then display and keep order of vehicles waiting to be picked up. Having passed all of the tests the WiVal System will be a completely functional valet system that can compete in today’s industry. Figure 9.1 depicts a basic overview of the testing that will occur during the final stages of our project. Testing!

Program! microcontroller!

Revise!and!repair!

Assemble!power! supply,! transmitter,!and! receivers!!!

Test!functionality!

Construct! chassis!and! mounting

Final!product! !

Figure 9.1 is a basic Testing Overview 85! !

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Testing is a very important part for the WiVal project. The goal in testing will be to verify the original goals, objectives, specifications, and requirements specified at the beginning of this document. To complete this task all equipment must be tested in a controlled environment, which will likely be the senior design lab. Measurements must be taken, and definitions must be categorically and methodically verified. In addition, all testing should be conducted in a manner that is as close to realistic with everyday situations as possible. In order to thoroughly confirm all requirements, specifications, goals, and objectives, a log will be maintained in a lab notebook. The usual equipment will be used that is available in the senior design lab, such as oscilloscopes and function generators. Other equipment will be borrowed or purchased if need be. During the build phases of the WiVal, testing must be done constantly to ensure that completed tasks are not undone by new programming or building. Initial testing is simply making sure that progress continues and that any setbacks will be minimized. After any of WiVal’s units are built, and the first phases of testing are complete, final testing will begin. This will consist of checking and rechecking that all requirements set forth are met.

9.2.1 The RF Transmitter As a significant feature, the RF transmitter for both the main station and the portable receiver’s will be tested independently. The members of Wival will then use the measured data obtained from the experiments to verify the desired and recommended features of the RF transmitter. Subsequently, the group will assemble a bread board, a function generator, an oscilloscope and a multimeter. The group will then start by placing the RF transmitter on the board and then connect the transmitter to the function generator in order to verify that the voltage is 3V.The oscilloscope will also be connected to verify the graph of the voltage for any faults. Next, the multimeter will be used to verify that the supplied current is 3.4mA. The transmitter output RF frequency has to be centered at 418 MHz to pass the frequency test. Figure 9.2.1 and 9.2.2 show some testing requirements which will be fulfilled in senior design 2.

Figure 9.2.1 on the left, expected modulation delay and Figure 9.2.2 on the right, current consumption vs. power output (With permission granted from Linx Technologies) 86! !

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9.2.2 The RF Receiver Primarily the RF receiver will be connected on the bread board and like the RF transmitters the voltage will be the first measurement because the group knows that the expected outcome is 3V and from previous experiments in labs the team members know what the expected value looks like on an oscilloscope. Next the multimeter will be used to measure the input current. Also the reception frequency of the RF receiver will be measured to ensure that it is 418Mhz.Figure 9.3 and 9.4 show the turn on response results provided by Linx technologies, this aid in the verification process. However additional testing of general components such as the power usage, gain and range will be done and analyzed in senior design 2. Since receivers are also going to be used in the portable receiver, the testing done will be put into practice for both the main station and the portable receiver

Figure 9.3 on the left and 9.4 on the right, show the turn on response time from VCC to PDN (With permission granted by Linx Technologies)

9.2.3 The main station and portable receivers In order to get the main station up and running, the members of Wival will have to test each component to verify that the selected divisions are working properly. Once this is achieved, each and every component will be assembled into the final design. The final component will then be tested rigorously to ensure that it meets all of Wival’s specifications and requirements. Every single component plays a role in the success of the main station; however the RF receiver, the RF transmitter the Microcontroller and the antennas will require the most time and attention. We can then verify our results based on the expected results from being an engineering student and using the various manuals that are provided by the manufacturers of the various parts. Figure 9.5 and 9.6 show some of the desired result for Wival’s design. These performance graphs will serve as a guide in the verification process of the success of the main station. However additional 87! !

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testing of general components such as the power usage, gain and range will be done and analyzed in senior design 2.

Figure 9.5 on the left and 9.6 on the right are samples of expected results RSSI response time and consumption Vs power correspondingly (With permission granted by Linx Technologies)

9.2.4 The Antennas Testing is a very important factor in getting an antenna to function well. A range test with different configurations of antenna length and types selected for use in this project will need to be conducted in order to find the most effective antenna combination for Wival. Both the main station and the portable receivers will be tested inside and outside, so as to accommodate for various factor. The ground plane also plays a critical role in the performance of the antenna when it is mounted on the PCB. While researching different types of Antennas, it was found that there are at least three essential decisive factors for testing antennas. 1. Gain 2. Range 3. Efficiency These three factors will be the main focus of the testing of the antennas both separately and with the main station and the portable receivers, in senior design 2.

9.3 Microcontroller Initial testing of the Texas Instruments ez430-F2012s will ensure that they can correctly differentiate between simple analog signals. The signals will then be increased in complexity until they reach the complexity required for the WiVal system. The next step will be to ensure that the Texas Instruments ez430F2012s can send the signals correctly. Both the Texas Instruments ez430F2012 for the main base and the Texas Instruments ez430-F2012 for the portable receiver must be able to send analog signals, and both Texas 88! !

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Instruments ez430-F2012s must be able to send a 4-bit digital signal in order to enable the LCD displays. After the initial testing, the system can be constructed, and the Texas Instruments ez430-F2012s will be tested to ensure that the system works in an ideal situation. An ideal situation being defined as one in which all signals are guaranteed to come in one at a time, at full strength. After that case has been verified, the Texas Instruments ez430-F2012s will be tested for less ideal cases. Testing will need to be done for the following cases: two pager units being activated at close to the same time, a pager unit being activated at the maximum desired range, a portable receiver receiving a signal at the maximum desired range, and the portable receiver or main base receives a signal at the same time that a key is pressed.

9.4 Programming For initial testing, each function in the program will be tested separately. First, the basic purpose of the function will be tested. Then, additional purposes will be added until the final function is verified working. The CheckSignal function will first be tested merely to ensure that it can recognize a signal coming in on the analog input line. After it has been verified that the CheckSignal function can recognize a signal, the function will be updated to include capturing the signal in its role. If the CheckSignal function can recognize the signal and capture the signal, it will be considered to be fully functional and complete. The DecodeSignal function will first be tested to ensure that it can take in a simple signal captured by the CheckSignal function, and pull the useful data from it. Once the CheckSignal function has been verified to be working properly, if the DecodeSignal function can accurately decode a signal passed from the CheckSignal function, then it will be considered to be fully functional and complete. The AddCar function will first be tested to ensure that it can take in an integer and add it to the list of cars in the correct slot. It will then be tested with a ring which already contains the car that has been sent to it, to ensure that it does not add the existing car to the ring multiple times. Finally, the AddCar function will be tested to make sure that it can accurately update the pointer to the most recent car added to the double linked list ring. If the AddCar function can accurately verify that a car is not in the ring already, add the car to the ring, and then update the pointer to the ring, then it will be considered to be fully functional and complete. The AlertUser function will be tested to ensure that it can send an analog signal capable of driving the speaker to make a sound to alert the user that a new car has been added to the ring. If the AlertUser function can manage to get the speaker to play a useable sound, then it will be considered to be fully functional and complete. The ClearLED function will be tested to ensure that it can send a digital signal to the decoder to activate the “clear” line. If, when the ClearLED 89! !

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function is called, the “clear” line becomes the only active line, then the ClearLED function will be considered to be fully functional and complete. The ToLED function will first be tested to ensure that it can take in an integer number and correctly break it down into a ten’s place and a one’s place. It will then be tested to ensure that it calls the correct sub functions for any given integer input. If the ToLED function can accurately break down an integer and call the corresponding functions, then it will be considered to be fully functional and complete. The OneOut, TwoOut, etc. functions will first be tested to ensure that when they are called, they produce the required outputs on the digital lines to the decoder, in the correct order, with no additional signals being sent. The Texas Instruments ez430-F2012 and the decoder will then be connected to the LEDs to ensure that the OneOut, TwoOut, etc. functions actually cause the correct number to be displayed. If the correct number is displayed when the OneOut, TwoOut, etc. functions are called, then they will be considered to be fully functional and complete. The CheckKeys function will first be tested to ensure that when it is called and no key is pressed, that it returns a value of zero to the main program. Next, it will be tested to ensure that when it is called and the forward key is pressed that it returns a value of one to the main program. Then, it will be tested to ensure that when it is called and the back key is pressed that it returns a value of two to the main program. Then, it will be tested to ensure that when it is called and the “latest” button is pressed that it returns a value of three to the main program. Finally, the CheckKeys function will be tested to ensure that when it is called and more than one button is pressed, that it returns a value of negative one to the main program. If the CheckKeys function returns the correct integer value under all stated conditions, then it will be considered to be fully functional and complete. The EncodeSignal function, on the main base, will be tested to ensure that it can translate an integer value to the correct signal. If the EncodeSignal function can reliably produce the correct signal, then it will be considered to be fully functional and complete. The SendSignal function, on the main base, will be tested to ensure that it can take a signal and properly transmit it through the analog output line. If the SendSignal function can reliably send the signals, then it will be considered to be fully functional and complete.

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Finances and Milestones 10.1 Introduction The WiVal project will call on the formal training of the group’s engineers in the fields of circuit design, computer system design, programming, system architectures, wireless systems, hardware and software interfacing. The project will also demand other skills, these additional skills are not formally taught in the EE or CE courses; however, they are skills vital to the success of graduating engineers entering the workforce. Some of these skills include: ! ! ! ! !

The ability to identify customer needs The ability to work efficiently in a team setting The ability to communicate ideas in a clear, professional manner Scheduling and time management Budgeting.

WiVal’s group will also be faced with challenging questions related to selfmanagement, ethics, and professionalism. The challenges and experiences in several areas should provide WiVal’s group with valuable insight to their futures in engineering. This project is the culmination of the group’s education in that the WiVal project will draw upon the skills, resources, and knowledge of each group member in such a way as to build confidence in the other members. This confidence will allow the members to move forward in their lives knowing that they are well trained engineers, capable of injecting their own form of value into the society in which technology is everywhere. WiVal is currently being self-financed. WiVal is hoping to keep the final budget under $630. For the final design our hopes are to create one - two receivers and three-four pagers and one main transmitter. Our original budget in the beginning of the semester was similar to the one in table 10.1a.

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Table 10.1a shows first budget layout. This first budget was a great guideline for maximizing the amount of money compiled for designing and building WiVal. As a group, WiVal allocated plenty of money to purchase everything that is required. This budget also gave WiVal the ability to do the research with the proper amount of information needed for choosing parts. The extra amount of money was dedicated to the project so that the group could choose components with confidence instead of worrying too much about cost. Each group member was allocated enough money to focus on the parts that were needed, and the parts that could maximize the potential of WiVal and its success. This original budget layout is what aimed WiVal towards its milestones. WiVal hopes to design and create a prototype of a wireless valet system that competes with existing products on the market. WiVal will aim itself towards finishing the design portion of this product by December 5th, 2008 as to be turned in by December 8th, 2008. WiVal’s milestone of designing this project by the respective due date appeared to be far from near when starting in the beginning of the semester. After lots of dedicated planning and hard work, WiVal committed themselves to success and worked towards a final product that could be built with the proposed design by the completion of the next semester. All of 92! !

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this would not have been possible without the necessary planning that comes with such a daunting project. The group worked until completion as to confirm that the proposed WiVal will succeed. The basic overview WiVal followed for maintaining a goal and an end date is shown in Figure 10.1b. Since each team member has a different class, work, and personal schedule, management is maintained through the use of meetings and constant communication through email. Each member has been assigned to overlook certain phases in WiVal’s design progress, but mainly there is a joint effort to research and complete WiVal’s project. No Team leader has been assigned since WiVal feels that there is great teamwork thus far and each individual is a leader in their respective phase. The team worked independently to gain the information we needed to provide the content of this document. A majority of the information enclosed was generated from prior knowledge gained during our education or from other sources. The other sources that we used were mostly available true the internet. We searched, sent emails, and browsed to find the information we needed. WiVal’s group interaction will be the key for our success in the course of this project. Various meeting times were set up to discuss the project and come up with ideas and solutions. Like research, much of WiVal’s design was done independently. We did have meetings to address WiVal’s specifications and have interactions, but for the most part, time was saved by making the designs on personal time. WiVal’s group agreed to meet twice a week to finalize a document so that the paper would be fluent and any bad and useless information would be replaced with relevant topics. The time needed to research the project was distributed evenly between all the members of the team. The team had weekly meetings on Tuesdays and Thursdays and additional planned discussion days. The discussions days where set up so that all the team members could talk about the progress relevant to their research, share ideas, and update the other members about new ideas and additions to the project. Each member was responsible for both ordering parts and several meetings where set up to edit the paper and provide everyone with updates on its progress.

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EEL!4914!Milestone!Overview Design!and! research!

Obtain! knowledge!of! wireless!devices

Hardware!fabrication

Software!design!and! testing!

Integration!and! testing*!

Review!documentation! and!report

Figure 10.1b shows an Overview of WiVal’s Milestones

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10.2 Finances As the semester came to a close, WiVal was able to capitalize on all the time allocated due to the careful planning in the beginning. The finances of the project were gathered early on. WiVal chose its parts early as to move forward in the design process as soon as was possible. Our final Budget is displayed in table 10.2 with exact part numbers, quantity and price.

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Table 10.2 Final Budget

10.3 Milestones WiVal hopes to accomplish everything that was planned from the beginning. As of this writing everything has gone as scheduled and the WiVal Project Documentation is complete, As a group, WiVal went through a challenging process of accommodating to the schedule of designing an engineering project. The group held itself together through hard work and dedication. WiVal’s group knew from the beginning that teamwork was essential to completing such a daunting task. With teamwork also came a necessary respect that was given to each other, and especially to the schedule. For an engineering project to be successful, a group must stick to and accomplish the milestones that are decided upon from the beginning. The schedule in table 10.3 shows the initial milestones set forth, with the completing dates accompanying them.

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Table 10.3 Finished Milestone WiVal can become a successful project if the group continues to accomplish all the milestones that lay ahead. The first portion of Senior Design is complete which next moves WiVal towards the final semester. The first half of Senior Design consists of mostly design and research. The final half takes the design 96! !

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and research phase and utilizes that to build and test a prototype. WiVal’s continued milestone for the next half of Senior Design are detailed next in Table 10.4.

Table 10.4 Future Milestones

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Final Comments 12.1 Final Comments Finding a project to settle on became an awkward task. Ideas were thrown from every direction. Ultimately the project chosen was the one that seemed the most technologically feasible and the most needed or the most likely to be used of the ideas. This group decided on WiVal. When WiVal had set out and started researching this project, our goal was to create a low cost, portable and easy to use wireless system which can benefit the valet and restaurant industry. As more research was done, decisions were made on the functions and devices for our original design to fit our requirements and budget. We faced some difficulties during the design such as choosing & purchasing electrical components. At times we couldn’t find the parts that we needed from the websites; we then called the companies or factories for parts and information. This experience allowed us to gain knowledge in the area of preparing for an Engineering Design project. WiVal hopes to accomplish a successful design of a Wireless Valet System. As mentioned earlier, the Valet Industry is one in which technology has slowly but surely affected it. As people move forward in time, new technologies surround everyone in ways that years ago, people could barely have imagined. WiVal hopes to establish itself in an Industry that can truly be changed. Technology is seeping into almost every other area of the Restaurant Industry, and WiVal seeks to take that perspective to the Valet Companies. Working within a profession allows one to see the negatives in the job that occur in everyday processes. As mentioned earlier, valet as a service has been around in some form for many years. For the last several decades, valet has employed the “pen and paper” method. The “pen and paper” method is one in which the valet employee gives the incoming person or customer a piece of paper that can later be collected and matched with the identifying ticket on the key chain. This method still works and is still used in most places that employ a valet service. This method is just another service that people who use that method are just waiting to improve. WiVal is another example of technology changing a traditional method. With the valet industry relying heavily on the “pen and paper” method, the concept of technology replacing this was inevitable. WiVal seeks to eliminate the use of the “pen and paper” method and bring forward a technological product that can accommodate customers and hopefully allow the Valet industry to profit in a way they never have. The WiVal brings a product that will only benefit the service. 98! !

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The companies that use this product will be moving their customer service into the next millennium. The goal behind WiVal is to have three basic units. WiVal will be optimal for all levels of valet service. The equipment is inexpensive and beneficial to the industry. The WiVal will accommodate to the employee who does not have a lot of technical knowledge. All of this will come together to create a strong product known as WiVal. WiVal’s group has high expectations about the prototype that is being built. The group expects results that satisfy the requirements mentioned earlier. The WiVal relies on simple electrical and analog signal fundamentals. The WiVal has several technical desired results. With all that needs to work, the WiVal should be able to benefit the company employing the technology. The WiVal has a strong idea aimed towards resolving prior problems with older methods and to reach goals that Valet Companies couldn’t reach before. The members of WiVal have several core goals for the WiVal Project. WiVal wants to design and build a project that challenges their abilities in engineering. This project has challenged WiVal’s group in ways that ultimately have become the educational “light at the end of the tunnel” in the pursuit of their engineering degrees. WiVal’s group has been determined to design and build a project that will enhance themselves in their respective areas for future occupations.

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Appendix I

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Figure 7.2.1 the LR series Transmitter Pin Assignment (With permission granted by Linx Technologies)

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Table 7.2.1 Pin description of the LR Series Transmitter (With permission granted by Linx Technologies)

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Appendix II

Figure 6.2 the LR series receiver Pin Assignment (With permission granted by Linx Technologies)

Table 6.2 Pin description of the LR Series Transmitter (With permission granted by Linx Technologies) 101! !

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Appendix III !

Component (Unit Price)

Location

Quantity

Price

RXM-418-LR ($10.00 each)

Linx Technologies

3

TXM-418-LR ($6.00 each)

Linx Technologies

2

CMD-KEY2-418 ($15.00 each)

Linx Technologies

3

Wires

RadioShack

n/a

P/W Series Antenna ($7.00)

Linx Technologies

2

CR2032 Battery Pack of 2 ($3.00) PCB Board Pressing ($7.00)

RadioShack

1

$30.00 $12.00 $45.00 $20.00 $14.00 $3.00

7-Segment LED #276-075 ($1.99) Microcontroller TI ez430F2012T ($3.33) Bantam Clip ($7.00)

RadioShack

4

$14.00 $8.00

Texas Instruments

2

$6.66

TheClip.com

3

$21.00 $14.00

2

PVC Plastic Sheets 2’ x 2’ ($7.00) Unknown Costs

2

$40.00 $227.66

Total !

Table 10.2

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Appendix IV Works Cited FCC, Part 15: Radio frequency devices, [Online Document], [cited 10 November 2008], Available http://www.fcc.gov/Bureaus/Engineering_Technology/Documents/cfr/1999/, retrieved October 16th, 2008 JTech, “Applications: restaurant server paging, waiter paging systems”, [Online Document], [cited 02 October 2008], Available http://www.jtech.com/products/serv_alert.htm, October 1, 2008 Innovonics, “EE1235D”, [Online Document], [cited 03 November 2008], Available http://www.inovonics.com/productssub.aspx?id=3572, retrievedOctober 19, 2008 Isaacs Tech, “Isaacs TECH Two Button Pager” [Online Document], [cited 03 November 2008], Available http://www.isaacstech.com/radio_products/sheets_manuals/pdf/612T_specs.PDF , Retrieved October 19, 2008 Linx Technologies, “Data Guide”,[Online Document], [November 2008], Available
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Parallax Inc., www.parallax.com [Online Document], [Cited October November 2, 2008], available www.parallax.com, retrieved October 15, 2008 Texas Instruments, www.ti.com [Online Document], [Cited November 3, 2008], Available www.ti.com, retrieved October 13, 2008

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Appendix V Permission Granted Subject: RE: RF Modules Date: Mon, 24 Nov 2008 12:04:24 -0800 From: [email protected] To: [email protected] Henry

You have our permission to use schematic diagrams and other related data from our website in your Senior Design paper. We do require that items used in your report indicate that they are used with permission of Linx Technologies.

Tech Support Linx Technologies [email protected] Phone:1-541-471-6256 Fax:1-541-471-6251 PO Box 390, Merlin, OR 97532 Shipping: 159 Ort Lane, Merlin, OR 97532 http://www.linxtechnologies.com http://www.antennafactor.com http://www.connectorcity.com

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Permission Pending Subject: : Innovonics Picture Date: Wed, 26 Nov 2008 11:09:24 -0800 From: [email protected] To: [email protected] To Whom it May Concern, My names is James O’Mara and I am currently a student at the University of Central Florida. I am working on an Engineering project that covers wireless technologies. I was hoping to be able to use a photo of the EE1235 DD Transmitter. If that is alright, I would love a confirmation. Thank you.

James

Subject: : Isaacs Tech Picture Date: Wed, 26 Nov 2008 11:11:02 From: [email protected] To: [email protected] To Whom it May Concern, My names is James O’Mara and I am currently a student at the University of Central Florida. I am working on an Engineering project that covers wireless technologies. I was hoping to be able to use a photo of the Isaacs Tech 612T Transmitter. If that is alright, I would love a confirmation. Thank you. James

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Subject: : Bantam Clip Picture Date: Wed, 26 Nov 2008 11:21:09 From: [email protected] To: [email protected] To Whom it May Concern, My names is James O’Mara and I am currently a student at the University of Central Florida. I am working on an Engineering project that covers wireless technologies. I was hoping to be able to use photos of the Super Bantam Clip and the Bantam Clip #500. If that is alright, I would love a confirmation. Thank you. James

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