A Presentation On Wireless Communication

A PRESENTATION ON WIRELESS COMMUNICATION

What Is Wireless Communication ? ØWireless communication is the transfer of information over a distance without the use of electrical conductors or "wires". ØThe distances involved may be short (a few meters as in television remote control) or long (thousands or millions of kilometers for radio communications). ØWhen the context is clear, the term is often shortened to "wireless". ØWireless communication is generally considered to be a branch of telecommunications.

ØIt encompasses various types of fixed, mobile, and portable two way radios, cellular telephones, personal digital assistants (PDAs), and wireless networking. ØOther examples of wireless technology include GPS units, garage door openers and or garage doors, wireless computer mice, keyboards and headsets, satellite television and cordless telephones.

History ØThe term "Wireless" came into public use to refer to a radio receiver or transceiver (a dual purpose receiver and transmitter device). ØEstablishing its usage in the field of wireless telegraphy early on; now the term is used to describe modern wireless connections such as in cellular networks and wireless broadband Internet. ØIt is also used in a general sense to refer to any type of operation that is implemented without the use of wires, such as "wireless remote control" or "wireless energy transfer", regardless of the specific technology that is used to accomplish the operation ØExamples - radio, infrared, ultrasonic.

WHAT IS WAP ? The wireless industry came up with the idea of WAP. The point of this standard was to show internet contents on wireless clients, like mobile phones. ØWAP stands for Wireless Application Protocol. ØWAP is an application communication protocol. ØWAP is used to access services and information. ØWAP is inherited from Internet standards. ØWAP is for handheld devices such as mobile phones. ØWAP is a protocol designed for micro browsers. ØWAP enables the creating of web applications for mobile devices. ØWAP uses the mark-up language WML (not HTML). ØWML is defined as an XML 1.0 application.

The Wireless Application Protocol ØWAP is published by the WAP Forum, founded in 1997 by Ericsson, Motorola, Nokia, and Unwired Planet. ØForum members now represent over 90% of the global handset market, as well as leading infrastructure providers, software developers and other organizations. ØThe WAP protocol is the leading standard for information services on wireless terminals like digital mobile phones. ØThe WAP standard is based on Internet standards (HTML, XML and TCP/IP). ØIt consists of a WML language specification, a WMLScript specification, and a Wireless Telephony Application Interface (WTAI) specification.

what happens when you access a Web site using a WAP-enabled device :ØYou turn on the device and open the minibrowser. ØThe device sends out a radio signal, searching for service. ØA connection is made with your service provider. ØYou select a Web site that you wish to view. ØA request is sent to a gateway server using WAP. ØThe gateway server retrieves the information via HTTP from the Web site. ØThe gateway server encodes the HTTP data as WML. ØThe WML-encoded data is sent to your device. ØYou see the wireless Internet version of the Web page you selected.

What happens between the gateway and the client relies on features of different parts of the WAP protocol stack :-

ØWAE - The Wireless Application Environment holds the tools that wireless Internet content developers use. These include WML and WMLScript, which is a scripting language used in conjunction with WML. It functions much like JavaScript. ØWSP - The Wireless Session Protocol determines whether a session between the device and the network will be connection-oriented or connectionless. ØWTP - The Wireless Transaction Protocol acts like a traffic cop, keeping the data flowing in a logical and smooth manner. It also determines how to classify each transaction request: üReliable two-way üReliable one-way üUnreliable one-way

What happens between the gateway and the client relies on features of different parts of the WAP protocol stack :Ø

WTLS - Wireless Transport Layer Security provides many of the same security features found in the Transport Layer Security (TLS) part of TCP/IP. It checks data integrity, provides encryption and performs client and server authentication. ØWDP - The Wireless Datagram Protocol works in conjunction with the network carrier layer . WDP makes it easy to adapt WAP to a variety of bearers because all that needs to change is the information maintained at this level. ØNetwork carriers - Also called bearers, these can be any of the existing technologies that wireless providers use, as long as information is provided at the WDP level to interface WAP with the bearer.

Examples of WAP use ü Checking train table information. ü Ticket purchase. ü Flight check in. ü Viewing traffic information. ü Checking weather conditions. ü Looking up stock values. ü Looking up phone numbers. ü Looking up addresses. ü Looking up sport results.

What is WML ?

Ø WML stands for Wireless Markup Language. It is a mark-up language inherited from HTML, but WML is based on XML, so it is much stricter than HTML. Ø WML is used to create pages that can be displayed in a WAP browser. Pages in WML are called DECKS. Decks are constructed as a set of CARDS.

What is WMLScript ? Ø WML uses WMLScript to run simple code on the client. Ø WMLScript is a light JavaScript language. Ø WML scripts are not embedded in the WML pages. Ø WML pages only contains references to script URLs. Ø WML scripts need to be compiled into byte code on a server before they can run in a WAP browser.

TYPES OF WIRELESS COMMUNICATION ØPC card (also known as PCMCIA) ØIrDA (Infrared Data Association) ØBluetooth wireless ØWi-Fi wireless ØUSB cable ØRadio

Ø PC card (also known as PCMCIA) Co nten ts ØMeaning of PC card or PCMCIA ØCard types Type Type Type Type

I II III IV

ØCard Information Structure ØCard Bus ØCard Bay ØDescendants and variants ØTechnological obsolescence

A PC Card network adapter

PC card (also known as PCMCIA)

A PC Card network adapter

Meaning of PC card or PCMCIA :-

ØPCMCIA stands for Personal Computer Memory Card International Association, the group of industry-leading companies that defines and develops the standard. ØWhile this acronym did clearly describe the original intentions of the organization's standard, it was difficult to say and remember, and was sometimes jokingly referred to as "People Can't Memorize Computer Industry Acronyms". ØTo aid in the widespread marketing and branding of the standard, and to account for the standard's widening scope (beyond just memory cards), the association acquired the rights to the simpler term "PC Card" from IBM, and began using it, rather than "PCMCIA", from version 2 of the specification onwards.

Card types üAll PC Card devices use an identical 68 pin dual row connecting interface.

üAll are 85.6 mm long and 54.0 mm wide. üThis is the same size as a credit card. The form factor is also used by the Common Interface form of Conditional Access Modules for DVB broadcasts. Type I ØCards designed to the original specification (version 1.x) are type I and feature a 16-bit interface. ØThey are 3.3 mm thick. ØType-I PC Card devices are typically used for memory devices such as RAM, flash memory, OTP, and SRAM cards.

Two PC Card devices: Xircom Real Port (top) type III and 3Com (bottom) type II.

Type I I

A PC Card network adapter

ØType-II PC Card devices feature a 16- or 32-bit interface. ØThey are 5.0/5.5 mm thick. ØType-II cards introduced I/O support, allowing devices to attach an array of peripherals or to provide connectors/slots to interfaces for which the host computer had no built-in support. ØFor example, many modem, network and TV cards use this form factor. ØDue to their thinness, most Type II interface cards feature miniature interface connectors on the card which are used together with a dongle: a short cable that adapts from the card's miniature connector to an external full-size connector. ØSome cards instead have a lump on the end with the connectors. This is more robust and convenient than a separate adaptor but can block the other slot where slots are present in a pair.

A PC Card network adapter

Type I II ØType-III PC Card devices are 16-bit or 32-bit. ØThese cards are 10.5 mm thick, allowing them to accommodate devices with components that would not fit type I or type II height. ØExamples are hard disk drive cards, and interface cards with fullsize connectors that do not require dongles (as is commonly required with type II interface cards).

Type I V ØType-IV cards, introduced by Toshiba, have not been officially standardized or sanctioned by the PCMCIA. ØThese cards are 16 mm thick.

Card Information Structure

A PC Card network adapter

ØThe Card Information Structure (CIS) is information stored on a PC card that contains information about the formatting and organization of the data on the card. ØThe CIS also contains information about: üThe type of card üSupported power supply options üSupported power saving features üThe manufacturer üModel number üand so on.

Card Information Structure (CIS)

ØWhen a card is unrecognized it is frequently because the CIS information is either lost or damaged.

Card Bus

A PC Card network adapter

ØCard Bus are PCMCIA 5.0 or later (JEIDA 4.2 or later) 32-bit PCMCIA devices, introduced in 1995 and present in laptops from late 1997 onward. ØCard Bus is effectively a 32-bit, 33 MHz PCI bus in the PC Card form factor. ØCard Bus includes bus mastering, which allows a controller on the bus to talk to other devices or memory without going through the CPU. ØMany chipsets are available for both PCI and Card Bus, such as those that support Wi-Fi. ØThe speed of Card Bus interfaces in 32 bit burst mode depends on the transfer type; in byte mode it is 33 MB/s, in Word mode it is 66 MB/s, and in DWord mode it is 132 MB/s.

Two Xircom Real Port Ethernet/56k modem cards. Top one is Card Bus, and the bottom is the 5 volt PCMCIA version. Note the slightly different notch.

Card Bus

A PC Card network adapter

ØThe notch on the left hand front of the device is slightly shallower on a Card Bus device, so a 32-bit device cannot be plugged into a slot that can only accept 16-bit devices. ØMost new slots are compatible with both Card Bus and the original 16-bit PC Card devices. ØCard bus cards have a gold band with eight small studs on the top of the card next to the pin sockets, which is not present in earlier models. Two Xircom Real Port Ethernet/56k modem cards. Top one is Card Bus, and the bottom is the 5 volt PCMCIA version. Note the slightly different notch.

Card Bay

A PC Card network adapter

ØCard Bay is a variant added to the PCMCIA specification in 2001. ØThis was intended to add some forward compatibility with USB and IEEE 1394, but was not universally adopted and only some notebooks have PC Card controllers with Card Bay features.

The PC Card bay when in use

Descendants and variants ØThe interface has spawned a generation of flash memory cards that set out to improve on the size and features of Type I cards: üCompact Flash üMini Card üSmart Media

A PC Card network adapter

ØFor example - The PC Card electrical specification is also used for Compact Flash, so a PC Card Compact Flash adapter need only be a socket adapter.

Descendant s Compact Flash

Mini Card

Smart Media socket adapter

ØExpress Card is a later specification from the PCMCIA, intended as a replacement for PC Card, built around the PCI Express and USB 2.0 standards.

A PC Card network adapter

ØThe PC Card standard is closed to further development and PCMCIA strongly encourages future product designs to utilize the Express Card interface. ØAs of 2007, the majority of laptops now ship with only Express Card slots or neither slot type (leaving expansion to USB and Fire wire only), though the Lenovo ThinkPad T60 and Z60m, among other models, currently ships with both Card Bus and Express Card slots.

variant s

USB Fire wire

Fire wire Variants

Express Card

ØExpress Card and Card Bus sockets are physically and electrically incompatible.

A PC Card network adapter

ØA simple mechanical adapter between the two formats is infeasible. ØSeveral companies now produce Express Card-to-Card Bus and Card bus-to-Express Card adapters that use a secondary slot to allow older cards to work with newer PCs and vice versa.

Express Card and Card Bus

Technological obsolescence

A PC Card network adapter

ØFire wire and USB devices are available for almost all functions that the PC Card interface was used for in the past, although it retains the advantage of containing devices entirely or almost entirely inside the case of the portable device.

ØThis can be an important consideration for portable systems, where additional external peripherals and their associated cables, space, and sometimes additional power supplies can reduce portability and convenience. ØEven in this case Express Card devices have the same advantages as PC Card devices, with additional bandwidth & functionality. ØOn the other hand many devices do not need the speed of PCI Express, and often PC Card devices with adequate performance can be found cheaply, as discounted new parts or on the used components market, and will suffice for many users' purposes.

Ø IrDA (Infrared Data Association) Conten ts ØMeaning of Infrared Data Association ØSpecifications 1.IrPHY 2.IrLAP 3.IrLMP 4.Tiny TP 5.IrCOMM 6.IrOBEX 7.IrLAN 8.IrSimple 9.IrSimpleShot Ø Popularity

Infrared Data Association Logo

IrDA (Infrared Data Association)

Mea nin g of

In fr ar ed Da ta

Infrared Data Association logo

ØThe Infrared Data Association (IrDA) defines physical specifications communications protocol standards for the short-range exchange of data over infrared light, for uses such as personal area networks (PANs). ØIrDA is a very short-range example of free space optical communication. ØIrDA interfaces are used in medical instrumentation, test and measurement equipment, palmtop computers, mobile phones, and laptop computers (most laptops and phones also offer Bluetooth but it is now becoming more common for Bluetooth to simply replace IrDA in new versions of products). ØIrDA specifications include IrPHY, IrLAP, IrLMP, IrCOMM, Tiny TP, IrOBEX, IrLAN and IrSimple. IrDA has now produced another standard, IrFM, for Infrared financial messaging (i.e., for making payments) also known as "Point & Pay". ØFor the devices to communicate via IrDA they must have a direct line of sight similar to a TV remote control.

Specifications 1.IrPHY (Infrared Physical Layer Specification)

Infrared Data Association logo

The mandatory IrPHY (Infrared Physical Layer Specification) is the lowest layer of the IrDA specifications. The most important specifications are:üRange

: standard 1 m

üLow power to low power

: 0.2 m

üStandard to low power

: 0.3 m

üAngle

: minimum cone ±15°

üSpeed

: 2.4 Kbit/s to 16 Mbit/s

üModulation

: baseband

ØIrDA transceivers communicate with infrared pulses in a cone that extends minimum 15 degrees half angle off center. ØThe IrDA physical specifications require that a minimum irradiance be maintained so that a signal is visible up to a meter away. ØThe specifications require that a maximum irradiance not be exceeded so that a receiver is not overwhelmed with brightness when a device comes close. ØIn practice, there are some devices on the market that do not reach one meter, while other devices may reach up to several meters. ØThere are also devices that do not tolerate extreme closeness. ØThe typical sweet spot for IrDA communications is from 5 to 60 cm (2.0 to 24 in) away from a transceiver, in the center of the cone.

Infrared Data Association logo

2. IrLAP (Infrared Link Access Protocol) Infrared Data Association logo

The mandatory IrLAP (Infrared Link Access Protocol) is the second layer of the IrDA specifications. It lies on top of the IrPHY layer and below the IrLMP layer. It represents the Data Link Layer of the OSI model. The most important specifications are: üAccess control üDiscovery of potential communication partners üEstablishing of a reliable bidirectional connection üDistribution of the Primary/Secondary device roles üNegotiation of QoS Parameters

ØOn the IrLAP layer the communicating devices are divided into a Primary Device and one or more Secondary Devices. ØThe Primary Device controls the Secondary Devices. Only if the Primary Device requests a Secondary Device to send is it allowed to do so.

3.IrLMP (Infrared Link Management Protocol) Infrared Data Association logo

ØThe mandatory IrLMP (Infrared Link Management Protocol) is the third layer of the IrDA specifications. ØIt can be broken down into two parts. First, the LM-MUX (Link Management Multiplexer) which lies on top of the IrLAP layer. Its most important achievements are: üProvides multiple logical channels üAllows change of Primary/Secondary devices ØSecond, the LM-IAS (Link Management Information Access Service), which provides a list, where service providers can register their services so other devices can access these services via querying the LM-IAS.

4.Tiny TP (Tiny Transport Protocol) Infrared Data Association logo

The optional Tiny TP (Tiny Transport Protocol) lies on top of the IrLMP layer. It provides: üTransportation of large messages by SAR (Segmentation and Reassembly) üFlow control by giving credits to every logical channel

5. IrCOMM (Infrared Communications Protocol)

Infrared Data Association logo

ØThe optional IrCOMM (Infrared Communications Protocol) lets the infrared device act like either a serial or parallel port. ØIt lies on top of the IrLMP layer.

Using IrCOMM to Replace a NULL Serial Cable

6. IrOBEX (Infrared Object Exchange) Infrared Data Association logo

ØThe optional IrOBEX (Infrared Object Exchange) provides the exchange of arbitrary data objects ØFor Example - vCard, vCalendar or even applications between infrared devices. ØIt lies on top of the Tiny TP protocol, so Tiny TP is mandatory for IrOBEX to work.

7. IrLAN (Infrared Local Area Network) Infrared Data Association logo

ØThe optional IrLAN (Infrared Local Area Network) provides the possibility to connect an infrared device to a local area network. There are three possible methods: üAccess Point üPeer to Peer üHosted ØAs IrLAN lies on top of the Tiny TP protocol, the Tiny TP protocol must be implemented for IrLAN to work.

CVIS uses a range of communication technologies including mobile cellular and wireless local area networks, short-range microwave and infrared to ensure that drivers avoid congestion

8. IrSimple ØIrSimple achieves at least 4 to 10 times faster data transmission speeds by improving the efficiency of the infrared IrDA protocol. ØA normal picture from a cell phone can be transferred within 1 second.

Infrared Data Association logo

9. IrSimpleShot (IrSS)

Infrared Data Association logo

ØOne of the primary targets of IrSimpleShot(IrSS) is to allow the millions of IrDA-enabled camera phones to wirelessly transfer pictures to printers, printer kiosks, flat panel TV's.

FIR Transceivers help Implement IrSimpleShot(TM) protocol

Popularity Infrared Data Association logo

ØIrDA was popular on laptops and some desktops during the late 90s through the early 2000s. ØIt has been displaced by other wireless technologies such as Wi-Fi and Bluetooth, favored because they don't need a direct line of sight, and can therefore support hardware such as mice and keyboards. ØIt is still used in some environments where interference makes radio-based wireless technologies unusable. ØIrDA popularity is making a comeback with its highly efficient IrSimple protocols by providing sub 1 second transfers of pictures between cell phones, printers, and display devices. ØIrDA hardware is still less expensive and doesn't share the same security problems encountered with wireless technologies such as Bluetooth.

ØBluetooth wireless

Co nten ts Ø Meaning of Bluetooth Ø Origin of the Bluetooth logo Ø Implementation Ø Uses

Bluetooth Logo

Bluetooth wireless Bluetooth Logo

Mean ing of ØThe word Bluetooth is an anglicized version of Old Norse Blátönn or Danish Blåtand, the name of the tenth-century king Harald I of Denmark and Norway, who united dissonant Scandinavian tribes into a single kingdom. ØThe implication is that Bluetooth does the same with communications protocols, uniting them into one universal standard A typical Bluetooth mobile phone headset.

Origin of the Bluetooth logo

Bluetooth Logo

ØThe Bluetooth logo design merges the Germanic runes analogous to the modern Latin letters H and B : (for Harald Bluetooth )

(Hagall) and

(Berkanan)

merged together, forming a bind rune.

A Bluetooth USB dongle with a 100m range.

Implementatio n

Bluetooth Logo

ØBluetooth uses a radio technology called frequency-hopping spread spectrum, which chops up the data being sent and transmits chunks of it on up to 79 frequencies. ØIn its basic mode, the modulation is Gaussian frequency-shift keying (GFSK). It can achieve a gross data rate of 1 Mb/s. ØBluetooth provides a way to connect and exchange information between devices such as mobile phones, telephones, laptops, personal computers, printers, Global Positioning System (GPS) receivers, digital cameras, and video game consoles through a secure, globally unlicensed Industrial, Scientific and Medical (ISM) 2.4 GHz short-range radio frequency bandwidth. ØThe Bluetooth specifications are developed and licensed by the Bluetooth Special Interest Group (SIG). The Bluetooth SIG consists of companies in the areas of telecommunication, computing, networking, and consumer electronics.

U ses

Bluetooth Logo

ØBluetooth is a standard and communications protocol primarily designed for low power consumption, with a short range (power-class-dependent: 1 meter, 10 meters, 100 meters) based on low-cost transceiver microchips in each device. ØBluetooth makes it possible for these devices to communicate with each other when they are in range. Because the devices use a radio (broadcast) communications system, they do not have to be in line of sight of each other. Class Class 1 Class 2 Class 3

Maximum Permitted Power mW (dBm) 100 mW (20 dBm) 2.5 mW (4 dBm) 1 mW (0 dBm)

Range(approximate)

~100 meters ~10 meters ~1 meter

In most cases the effective range of class 2 devices is extended if they connect to a class 1 transceiver, compared to a pure class 2 network.

Bluetooth Logo

This is accomplished by the higher sensitivity and transmission power of Class 1 devices.

Version

Data Rate

Version 1.2 Version 2.0 + EDR WiMedia Alliance (proposed)

1 Mbit/s 3 Mbit/s 53 - 480 Mbit/s

Nokia BH-208 headset internals

A typical Bluetooth USB dongle

An internal notebook Bluetooth card (14×36×4 mm)

ØWi-Fi wireless Conten ts ØMeaning of Wi-Fi wireless ØHistory ØUses

Wi-Fi logo

Wi-Fi wireless Meaning of Wi-Fi wireless :ØWi-Fi is a trademark of the Wi-Fi Alliance for certified products based on the IEEE 802.11 standards (also called Wireless LAN (WLAN) and Wi-Fi). ØThis certification warrants interoperability between different wireless devices. ØThe term Wi-Fi often is used by the public as a synonym for wireless Internet (WLAN); but not every wireless Internet product has a Wi-Fi certification, which may be because of certification costs that must be paid for each certified device type. ØWi-Fi is supported by most personal computer operating systems, many game consoles, laptops, smartphones, printers, and other peripherals

Wi-Fi

Histor y ØWi-Fi uses both single carrier direct-

Wi-Fi

sequence spread spectrum radio technology (part of the larger family of spread spectrum systems) and multi-carrier OFDM (Orthogonal Frequency Division Multiplexing) radio technology. ØThe regulations for unlicensed spread spectrum enabled the development of Wi-Fi, its onetime competitor HomeRF, Bluetooth, and many other products such as some types of cordless telephones.

Half-size ISA 2.4 GHz WaveLAN card by AT&T

ØUnlicensed spread spectrum was first made available in the US by the Federal Communications Commission in 1985 and these FCC regulations were later copied with some changes in many other countries enabling use of this technology in all major countries. ØThe FCC action was proposed by Michael Marcus of the FCC staff in 1980 and the subsequent regulatory action took 5 more years.

It was part of a broader proposal to allow civil use of spread spectrum technology and was opposed at the time by main stream equipment manufacturers and many radio system operators.

Wi-Fi

The precursor to Wi-Fi was invented in 1991 by NCR Corporation/AT&T (later Lucent & Agere Systems) in Nieuwegein, the Netherlands. It was initially intended for cashier systems; the first wireless products were brought on the market under the name WaveLAN with speeds of 1 Mbit/s to 2 Mbit/s. Vic Hayes, who held the chair of IEEE 802.11 for 10 years and has been named the 'father of Wi-Fi,' was involved in designing standards such as IEEE 802.11b, and 802.11a.

A keychain size Wi-Fi detector

Uses

Wi-Fi

ØA Wi-Fi enabled device such as a PC, game console, mobile phone, MP3 player or PDA can connect to the Internet when within range of a wireless network connected to the Internet.

A Wi-Fi antenna

ØThe coverage of one or more interconnected access points — called a hotspot — can comprise an area as small as a single room with wireless-opaque walls or as large as many square miles covered by overlapping access points. ØWi-Fi technology has served to set up mesh networks, for example, in London. ØBoth architectures can operate in community networks.

A roof mounted Wi-Fi antenna

ØUSB cable (Universal Serial Bus)

Co nten t ØMeaning of USB ØHistory

ØDevice classes 1. USB mass-storage 2. Human-interface devices (HIDs) Original USB Logo

ØTypes of USB connector 2. USB-A. 3. USB-B. 4. Mini and micro. 5. USB OTG Sockets: Mini-AB, Micro-AB. 6. Proprietary connectors and formats. ØUses Wireless USB Logo

USB cableSerial (Universal Bus)

Original

Meaning of USB :ØIn information technology, Universal Serial Bus

(USB) is a serial bus standard to connect devices to a host computer.

The USB trident logo

A USB Series “A” plug, the most common USB plug

ØUSB was designed to allow many peripherals to be connected using a single standardized interface socket and to improve plug and play capabilities by allowing hot swapping; that is, by allowing devices to be connected and disconnected without rebooting the computer or turning off the device. ØOther convenient features include providing power to low-consumption devices, eliminating the need for an external power supply; and allowing many devices to be used without requiring manufacturer-specific device drivers to be installed.

Histor y was introduced in 1994. ØThe USB 1.0 specification

Original

ØUSB was created by the core group of companies that consisted of Intel, Compaq, Microsoft, Digital, IBM, and Northern Telecom. ØIntel produced the UHCI host controller and open software stack; Microsoft produced a USB software stack for Windows and co-authored the OHCI host controller specification with National Semiconductor and Compaq; Philips produced early USB-Audio; and TI produced the most widely used hub chips. ØUSB was intended to replace the multitude of connectors at the back of PCs, as well as to simplify software configuration of communication devices. ØThe USB 2.0 specification was released in April 2000 and was standardized by the USB-IF at the end of 2001. ØHewlett-Packard, Intel, Lucent (now LSI Corporation since its merger with Lucent spinoff Agere Systems), Microsoft, NEC, and Philips jointly led the initiative to develop a higher data transfer rate, 480 Mbit/s, than the 1.0 specification of 12 Mbit/s.

Original

Vodafone 3G USB

ØThe USB 3.0 specification was released on November 17, 2008 by the USB 3.0 Promoter Group. ØIt has a transfer rate of up to 10 times faster than the USB 2.0 version and has been dubbed the Super Speed USB.

A conventional USB hub.

ØEquipment conforming with any version of the standard will also work with devices designed to any previous specification (a property known as backward compatibility).

Device classes

Original

USB defines class codes used to identify a device’s functionality and to load a device driver based on that functionality. This enables a device driver writer to support devices from different manufacturers that comply with a given class code. Device classes include:

1. USB massstorage

Original

ØUSB implements connections to storage devices using a set of standards called the USB mass storage device class (referred to as MSC or UMS). ØThis was initially intended for traditional magnetic and optical drives, but has been extended to support a wide variety of devices, particularly flash drives. ØThis generality is because many systems can be controlled with the familiar idiom of file manipulation within directories (The process of making a novel device look like a familiar device is also known as extension). ØThough most newer computers are capable of booting off USB Mass Storage devices, USB is not intended to be a primary bus for a computer's internal storage: buses such as ATA (IDE), Serial ATA (SATA), and SCSI fulfill that role. ØHowever, USB has one important advantage in that it is possible to install and remove devices without opening the computer case.

ØOriginally conceived and still used today for optical storage devices (CD-RW drives, DVD drives, etc.), a number of manufacturers offer external portable USB hard drives, or empty enclosures for drives, that offer performance comparable to internal drives[citation needed].

Original

ØThese external drives usually contain a translating device that interfaces a drive of conventional technology (IDE, ATA, SATA, ATAPI, or even SCSI) to a USB port. ØFunctionally, the drive appears to the user just like an internal drive. ØOther competing standards that allow for external connectivity are eSATA and FireWire. ØAnother use for USB Mass Storage devices is the portable execution of software applications without the need of installation on the host computer,e.g. Web Browser, VoIP, etc.

A flash drive, a typical USB mass-storage device.

2. Human-interface devices (HIDs)INTERFACE

Original

ØMice and keyboards are frequently fitted with USB connectors, but because most PC motherboards still retain PS/2 connectors for the keyboard and mouse as of 2007, they are often supplied with a small USBto-PS/2 adaptor, allowing usage with either USB or PS/2 interface.

CABLES

ØThere is no logic inside these adaptors: they make use of the fact that such HID interfaces are equipped with controllers that are capable of serving both the USB and the PS/2 protocol, and automatically detect which type of port they are plugged into. ØJoysticks, keypads, tablets and other human-interface devices are also progressively migrating from MIDI, PC game port, and PS/2 connectors to USB.

Types of USB connector : 1. USB-A ØThe Standard-A type of USB connector takes on

Original

the appearance of a flattened rectangle that plugs into downstream-port sockets on the USB host or a hub and receives power. ØThis kind of connector is most frequently seen on cables that are permanently attached to a device, such as one on a cable that connects a keyboard or mouse to the computer.

A fl a ma sh dr ss-s iv tor e, a t age y dev pical U ice SB .

USB clea vacuu m ner

Different types of USB connectors from left to right • 8-pin AGOX connector • Mini-B plug • Type B plug • Type A receptacle • Type A plug

Hua

wei

E22 0 mo HSD dem PA USB

2. USB-B

Original

ØStandard-B connectors—which have a square shape with beveled exterior corners—typically plug into upstream sockets on devices that use a removable cable, e.g. between a hub and a printer. ØType B plugs deliver power and are therefore analogous to a power socket. Pin configuration of the USB connectors Standard A/B, viewed from face of plug

ØThis two-connector scheme prevents a user from accidentally creating a loop.

3. Mini and micro

Original

ØVarious connectors have been used for smaller devices such as PDAs, mobile phones or digital cameras. ØThese include the nowdeprecated(but standardized) Mini-A and the current standard Mini-B, Micro-A, and Micro-B connectors. ØThe Mini-A and Mini-B plugs are approximately 3 by 7 mm. ØWhile the Micro plugs have a similar width but approximately half the thickness, enabling their integration into thinner portable devices.

Schematic diagram of Standard, Mini, and Micro USB receptacles.

4. USB OTG Sockets : MiniAB, Micro-AB

Original

ØExcept for special standard-to-Mini-A and standardto-Micro-A adapters, USB cables always have an Aconnector and a B-connector, on opposite ends. ØA-connectors can always connect to A-sockets; Bconnectors can always connect B-sockets. ØThese sockets all come in standard, mini, and micro versions. ØFor USB On-The-Go (or 'OTG') support for another socket type is defined: the AB, in both mini and micro versions. ØIt can accept both A and B connector, through careful mechanical design. ØOTG software detects the difference by use of the ID pin, which is grounded in A-connectors and is otherwise floating.

ØWhen an A-connector is connected to an AB socket, the socket supplies VBUS power to the cable and starts in the host role.

Original

ØWhen a B-connector is used, the socket consumes VBUS power and starts in the peripheral or device role. ØOTG allows those two roles to be switched by

Type A and Type B

USB Plugs and Sockets

5. Proprietary connectors and formats

Original

ØMicrosoft's original Xbox game console uses standard USB 1.1 signaling in its controllers and memory cards, but features proprietary connectors and ports. ØIBM UltraPort uses standard USB signaling, but via a proprietary connection format. ØAmerican Power Conversion uses USB signaling and HID device class on its uninterruptible power supplies using 10P10C connectors. ØHTC manufactures Windows Mobile-based Communicators and the T-Mobile G1 which have a proprietary connector called HTC ExtUSB. ØThe ExtUSB combines mini-USB (with which it is backwards-compatible) with audio/video input and output in an 11-pin connector.

ExtUSB

Original

ØNokia includes a USB connection as part of the Pop-Port connector on some older mobile phone models. ØThe second- and third-generation iPod Shuffle use a TRS connector to carry USB, audio, or power signals. ØIriver added a fifth power pin within USB-A plugs for higher power and faster charging, used for the iriver U10 series. Proprietary connectors and formats

ØA mini-USB version contains a matching extra power pin for the cradle.

U ses ØWireless USB is used in game controllers, printers, scanners, digital cameras, MP3 players, hard disks and flash drives. ØIt is also suitable for transferring parallel video streams. ØKensington released a Wireless USB universal docking station in August, 2008.

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Co nten t

ØRadio

ØMeaning of Radio ØProcesses ØHistory 1 Invention 2 Development ØUses of radio 1 Audio 2 Telephony 3 Video 4 Navigation 5 Radar 6 Data (digital radio) 7 Heating 8 Amateur radio service 9 Unlicensed radio services 10 Radio control (RC) ØThe electromagnetic spectrum

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Classic radio receiver dial

ØRadio

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Meaning of Radio :ØRadio is the transmission of signals by modulation of electromagnetic waves with frequencies below those of visible light. ØElectromagnetic radiation travels by means of oscillating electromagnetic fields that pass through the air and the vacuum of space. ØInformation is carried by systematically changing (modulating) some property of the radiated waves, such as amplitude, frequency, or phase. ØWhen radio waves pass an electrical conductor, the oscillating fields induce an alternating current in the conductor. ØThis can be detected and transformed into sound or other signals that carry information.

Processe s

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ØRadio systems used for communications will have the following elements. ØWith more than 100 years of development, each process is implemented by a wide range of methods, specialized for different communications purposes. ØEach system contains a transmitter. ØThis consists of a source of electrical energy, producing alternating current of a desired frequency of oscillation. ØThe transmitter contains a system to modulate (change) some property of the energy produced to impress a signal on it.

ØThis modulation might be as simple as turning the energy on and off, or altering more subtle properties such as amplitude, frequency, phase, or combinations of these properties. ØThe transmitter sends the modulated electrical energy to an antenna; this structure converts the rapidly-changing alternating current into an electromagnetic wave that can move through free space. ØEarly radio systems relied entirely on the energy collected by an antenna to produce signals for the operator. ØRadio became more useful after the invention of electronic devices such as the vacuum tube and later the transistor, which made it possible to amplify weak signals. ØToday radio systems are used for applications from walkie-talkie children's toys to the control of space vehicles, as well as for broadcasting, and many other applications.

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History

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1. Invention :ØDevelopment from a laboratory

demonstration to commercial utility spanned several decades and required the efforts of many practitioners. ØThomas Edison applied in 1885 to the U.S. Patent Office for a patent on a wireless telegraphy system which anticipated later developments in the field. ØThe patent was granted as Patent # 465971 on December 29, 1891, and Guglielmo Marconi felt it necessary to purchase rights to the Edison wireless telegraphy patent as a foundation stone of his own subsequent work in wireless telegraphy.

Tesla demonstrating wireless transmissions during his high frequency and potential lecture of 1891. After continued research, Tesla presented the fundamentals of radio in 1893.

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ØIn 1893, in St. Louis, Missouri, Nikola Tesla made devices for his experiments with electricity. ØAddressing the Franklin Institute in Philadelphia and the National Electric Light Association, he described and demonstrated in detail the principles of his wireless work. Telephone (1901).

Herald

in

Budapest,

Hungary

ØThe descriptions contained all the elements that were later incorporated into radio systems before the development of the vacuum tube.

ØHe initially experimented with magnetic receivers, unlike the coherers (detecting devices consisting of tubes filled with iron filings which had been invented by Temistocle Calzecchi-Onesti at Fermo in Italy in 1884) used by Guglielmo Marconi and other early experimenters

ØThe first radio couldn't transmit sound or speech and was called the "wireless telegraph."

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ØThe first public demonstration of wireless telegraphy took place in the lecture theater of the Oxford University Museum of Natural History on August 14, 1894, carried out by Professor Oliver Lodge and Alexander Muirhead. During the demonstration a radio signal was sent from the neighboring Clarendon laboratory building, and received by apparatus in the lecture theater. ØIn 1895 Alexander Stepanovich Popov built his first radio receiver, which contained a coherer. ØFurther refined as a lightning detector, it was presented to the Russian Physical and Chemical Society on May 7, 1895. ØA depiction of Popov's lightning detector was printed in the Journal of the Russian Physical and Chemical Society the same year. ØPopov's receiver was created on the improved basis of Lodge's receiver, and originally intended for reproduction of its experiments.

2. Development :-

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ØIn 1896, Marconi was awarded the British patent 12039, Improvements in transmitting electrical impulses and signals and in apparatus there-for, for radio. ØIn 1897 he established the world's first radio station on the Isle of Wight, England. ØMarconi opened the world's first "wireless" factory in This photo shows an early 1930's wooden radio Hall Street, Chelmsford, England in 1898, employing receiver in the classic "cathedral" shape around 50 people. ØOne of the first developments in the early 20th century (1900-1959) was that aircraft used commercial AM radio stations for navigation. ØThis continued until the early 1960s when VOR systems finally became widespread (though AM stations are still marked on U.S. aviation charts). ØIn the early 1930s, single sideband and frequency modulation were invented by amateur radio operators.

Uses of radio :-

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1. ØAMAudio broadcast radio sends music and voice in the Medium Frequency (MF, 0.3 MHz to 3 MHz) radio spectrum.

ØAM radio uses amplitude modulation, in which the amplitude of the transmitted signal is made proportional to the sound amplitude captured (transduced) by the microphone, while the transmitted frequency remains unchanged.

A Fisher 500 AM/FM hi-fi receiver from 1959.

ØTransmissions are affected by static and interference because lightning and other sources of radio emissions on the same frequency add their amplitudes to the original transmitted amplitude. ØIn the early part of the 20th century, American AM radio stations broadcast with powers as high as 500 kW, and some could be heard worldwide; these stations' transmitters were commandeered for military use by the US Government during World War II.

2. Telephony

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ØMobile phones transmit to a local cell site (transmitter/receiver) that ultimately connects to the public switched telephone network (PSTN) through an optic fiber or microwave radio and other network elements.

Pure One Classic- DAB Digital Radio from 2008

ØWhen the mobile phone nears the edge of the cell site's radio coverage area, the central computer switches the phone to a new cell.

ØCell phones originally used FM, but now most use various digital modulation schemes. ØRecent developments in Sweden (such as DROPme) allow for the instant downloading of digital material from a radio broadcast (such as a song) to a mobile phone. ØSatellite phones use satellites rather than cell towers to communicate.

3. Video

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ØTelevision sends the picture as AM and the sound as FM, with the sound carrier a fixed frequency (4.5 MHz in the NTSC system) away from the video carrier. ØAnalog television also uses a vestigial sideband on the video carrier to reduce the bandwidth required. ØDigital television uses 8VSB modulation in North America (under the ATSC digital television standard), and COFDM modulation elsewhere in the world (using the DVB-T standard). ØA Reed–Solomon error correction code adds redundant correction codes and allows reliable reception during moderate data loss. ØAlthough many current and future codecs can be sent in the MPEG-2 transport stream container format, as of 2006 most systems use a standard-definition format almost identical to DVD: MPEG-2 video in Anamorphic widescreen and MPEG layer 2 (MP2) audio.

4. Navigation

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ØAll satellite navigation systems use satellites with precision clocks. ØThe satellite transmits its position, and the time of the transmission. ØThe receiver listens to four satellites, and can figure its position as being on a line that is tangent to a spherical shell around each satellite, determined by the time-of-flight of the radio signals from the satellite. ØA computer in the receiver does the math. ØRadio direction-finding is the oldest form of radio navigation. ØBefore 1960 navigators used movable loop antennas to locate commercial AM stations near cities. ØIn some cases they used marine radiolocation beacons, which share a range of frequencies just above AM radio with amateur radio operators.

The Radio 5. Portal Radar ØRadar (Radio Detection And Ranging) detects objects at a distance by

bouncing radio waves off them.

ØThe delay caused by the echo measures the distance. The direction of the beam determines the direction of the reflection. ØThe polarization and frequency of the return can sense the type of surface. ØNavigational radars scan a wide area two to four times per minute. ØThey use very short waves that reflect from earth and stone. ØThey are common on commercial ships and long-distance commercial aircraft. ØGeneral purpose radars generally use navigational radar frequencies, but modulate and polarize the pulse so the receiver can determine the type of surface of the reflector.

6. Data (digital radio)

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ØMost new radio systems are digital, see also: Digital TV, Satellite Radio, Digital Audio Broadcasting. ØThe oldest form of digital broadcast was spark gap telegraphy, used by pioneers such as Marconi. ØBy pressing the key, the operator could send messages in Morse code by energizing a rotating commutating spark gap. ØThe rotating commutator produced a tone in the receiver, where a simple spark gap would produce a hiss, indistinguishable from static. ØSpark gap transmitters are now illegal, because their transmissions span several hundred megahertz. ØThis is very wasteful of both radio frequencies and power.

Modern GPS receivers.

7. Heating

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ØRadio-frequency energy generated for heating of objects is generally not intended to radiate outside of the generating equipment, to prevent interference with other radio signals. ØMicrowave ovens use intense radio waves to heat food. ØDiathermy equipment is used in surgery for sealing of blood vessels. ØInduction furnaces are used for melting metal for casting.

8. Amateur radio ØAmateur radio, also known as "ham radio", is a service

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hobby in which enthusiasts are licensed to communicate on a number of bands in the radio frequency spectrum non-commercially and for their own enjoyment. ØThey may also provide emergency and public service assistance. ØThis has been very beneficial in emergencies, saving lives in many instances. ØRadio amateurs use a variety of modes, including nostalgic ones like morse code and experimental ones like Low-Frequency Experimental Radio.

Amateur radio station with multiple receivers and transceivers

ØSeveral forms of radio were pioneered by radio amateurs and later became commercially important including FM, single-sideband (SSB), AM, digital packet radio and satellite repeaters. ØSome amateur frequencies may be disrupted by power-line internet service.

9. Unlicensed radio services ØUnlicensed, government-authorized personal radio

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services such as Citizens' band radio in Australia, the USA, and Europe, and Family Radio Service and Multi-Use Radio Service in North America exist to provide simple, (usually) short range communication for individuals and small groups, without the overhead of licensing. ØSimilar services exist in other parts of the world. These radio services involve the use of handheld units. ØFree radio stations, sometimes called pirate radio or "clandestine" stations, are unauthorized, unlicensed, illegal broadcasting stations. ØThese are often low power transmitters operated on sporadic schedules by hobbyists, community activists, or political and cultural dissidents. ØSome pirate stations operating offshore in parts of Europe and the United Kingdom more closely resembled legal stations, maintaining regular schedules, using high power, and selling commercial advertising time.

10. Radio control (RC)controls use radio waves to ØRadio remote

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transmit control data to a remote object as in some early forms of guided missile, some early TV remotes and a range of model boats, cars and airplanes. ØLarge industrial remote-controlled equipment such as cranes and switching locomotives now usually use digital radio techniques to ensure safety and reliability. ØIn Madison Square Garden, at the Electrical Exhibition of 1898, Nikola Tesla successfully demonstrated a radio-controlled boat. ØHe was awarded U.S. patent No. 613,809 for a "Method of and Apparatus for Controlling Mechanism of Moving Vessels or Vehicles.

SYMA DragonFly Radio Remote Control Helicopter!

The electromagnetic spectrum

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ØRadio waves are a form of electromagnetic radiation that are created when a charged object, such as an electron, accelerates with a frequency that lies in the radio frequency (RF) portion of the electromagnetic spectrum. ØIn radio, this acceleration is caused by an alternating current in an antenna.

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ELECTROMAGNETIC SPESTRUM OR EM SPECTRUM

ØRadio frequencies occupy the range from a few tens of hertz to three hundred gigahertz, although commercially important uses of radio use only a small part of this spectrum. ØOther types of electromagnetic radiation, with frequencies above the RF range, are microwave, infrared, visible light, ultraviolet, X-rays and gamma rays. ØSince the energy of an individual photon of radio frequency is too low to remove an electron from an atom, radio waves are classified as nonionizing radiation.

Reference s ühttp://www.wikipedia.org ühttp://www.acrosswireless.com ühttp://wireless.fcc.go ühttp://www.wirelessdevnet.com ühttp://www.schoolsgalore.com