Ch-1-2 Introduction To Cellular Mobile Communications

Cellular Mobile Communications-I An In tr oduction Dr. Nasir D. Gohar

http://www.stanford.edu/class/ee359/lectures.html Lecture Notes by Professor Reynold Cheung www.nmscommunications.com

Other Internet Resources

Cellular Mobile Communications-I An Introduction

Cell Phone Growth in Pakistan & Worldwide  According to a Media Report (Goliath, May 25, 2005), Cell Phones in Pakistan to Touch 15M mark in December 2005  Another Media Report (Middle East Times, June 20, 2006) Predicts the number of Cell Phones will rise from 2.2 Billion to 3 Billion worldwide by the end of Year 2008  According to MOBILEDIA (Jan 20, 2006)  U.S. offers more room for growth than Russia, and Japan offers

greater future growth than South Africa  The number of mobile subscribers worldwide reached over 2 billion by the end of 2005, and is predicted to rise to 3.96 billion by 2011  The Asia Pacific Region will account for 50% of the total number of subscribers worldwide by the end of this decade with a staggering 1.067 billion subscribers shared between China and India alone, the world's two biggest mobile markets

Cellular Mobile Communications-I An Introduction

Several Types of Mobile Radio Systems  Garage Door Controller [<100 MHz]  Remote Controllers [TV/VCR/DISH][Infra-Red: 1-100 THz]  Cordless Telephone [<100 MHz]  Hand-Held Radio [Walki-Talki] [VHF-UHF:40-480 MHz]  Pagers/Beepers [< 1 GHz]  Cellular Mobile Telephone[<2 GHz]

Classification  Simplex System: Communication is possible in only one direction : Garage Door Controller, Remote Controllers [TV/VCR/DISH] Pagers/Beepers

 Semi-Duplex System: Communication is possible in two directions but one talks and other listens at any time[Push to Talk System]: Walki-Talki

 Duplex System: Communication is possible in both directions at any time: Cellular Telephone [FDD or TDD]

Cellular Mobile Communications-I An Introduction

Paging System: For Transmission of Brief Numeric/Alphanumeric/Voice Messages [Pages] to Subscriber

 To Notify/Alert the User  Simplex Service  Modern Paging Systems Can Send News Head-Lines, Stock Info, or Fax  Application Dependent System Range [2 Km to World-wide] City 1 Land Line Link

Paging Terminal

PSTN City 2 PAGING CONTROL CENTRE

Land Line Link Paging Terminal

City N Paging Terminal

Cellular Mobile Communications-I An Introduction

Cordless Telephone System:

To Connect a Fixed Base Station to a Portable Cordless Handset  Early Systems (1980s) have very limited range of few tens of meters [within a House Premises]  Modern Systems [PACS, DECT, PHS, PCS] can provide a limited range & mobility within Urban Centers Cordless Handset

PSTN

Fixed Base Station

Cellular Mobile Communications-I An Introduction

Limitations of Simple Mobile Radio Systems The Cellular Approach

 Divides the Entire Service Area into Several Small Cells  Reuse the Frequency

Basic Components of a Cellular Telephone System  Cellular Mobile Phone: A light-weight hand-held set

which is an outcome of the marriage of Graham Bell’s Plain Old Telephone Technology [1876] and Marconi’s Radio Technology [1894] [although a very late delivery but very cute]  Base Station: A Low Power Transmitter, other Radio Equipment [Transceivers] plus a small Tower

 Mobile Switching Center [MSC] /Mobile Telephone Switching Office[MTSO]  An Interface between Base Stations and the PSTN  Controls all the Base Stations in the Region and Processes User ID

and other Call Parameters  A typical MSC can handle up to 100,000 Mobiles, and 5000 Simultaneous Calls  Handles Handoff Requests, Call Initiation Requests, and all Billing & System Maintenance Functions

Cellular Mobile Communications-I An Introduction

Cellular Mobile Communications-I An Introduction

 The Cellular Concept  RF spectrum is a valuable and scarce commodity  RF signals attenuate over distance  Cellular network divides coverage area into cells, each served by its own base station transceiver and antenna  Low (er) power transmitters used by BSs; transmission range determines cell boundary  RF spectrum divided into distinct groups of channels  Adjacent cells are (usually) assigned different channel groups to avoid interference  Cells separated by a sufficiently large distance to avoid mutual interference can be assigned the same channel group ⇒ frequency reuse among co-channel cells

Cellular Mobile Communications-I An Introduction

 An Example of Frequency Reuse 





Suppose we have spectrum

for 100 voice channels Scenario 1: a high power base station covering entire area – system capacity = 100 channels Scenario 2: divide spectrum into 4 groups of 25 channels each; cells (1, 7), (2, 4), (3, 5), 6 are assigned distinct channel groups – system capacity = 175 channels

Cellular Mobile Communications-I An Introduction

Frequency Reuse Factor



Frequency Reuse Factor N = No. of Distinct Channel Groups = Maximum Cluster Size

Cellular Mobile Communications-I An Introduction

Frequency Reuse Example-2  Suppose W = 25 MHz and B = 25 KHz/voice channel  W/B = 1000 voice channels can be supported over the spectrum  Scenario 1: a high power base station covering entire area (M = N = 1) ⇒ system capacity n = 1000 users  Scenario 2:

 Coverage area divided into M = 20 cells with reuse factor N = 4  Each cluster accommodate 1000 active users  5 clusters in coverage area ⇒ system capacity n = 5000 users

 Scenario 3:  M = 100 cells, N = 4 ⇒ system capacity n = 25000 users

 Scenario 4:  M = 100 cells, N = 1 ⇒ system capacity n = 100000 users

Cellular Mobile Communications-I An Introduction

 Common Air Interface (CAI) Common Air Interface: A Standard that defines Communication between a Base Station and Mobile Specifies Four Channels [Voice Channels and Control / Setup Channels] FVC: Forward Voice Channel RVC: Reverse Voice Channel FCC: Forward Control Channel RCC: Reverse Control Channel

Reverse Channel

Forward Channel

Cellular Mobile Communications-I An Introduction

 Call Setup Procedure Cellular Phone Codes: Special Codes are associated with each Cell Phone to identify the phone, its owner, and service provider: Electronic Serial Number(ESN) -A Unique 32-bit Code Mobile Identification Number(MIN): A Subscriber’s Telephone Number  Station Class mark (SCM): Indicates the Max Tx Power for the User

When a Cellular Phone is turned on and Initiates a Call:[see next slide] Monitors the Control Channels and gets hold on to the strongest one Makes a Call Initiation Request[Dials the Called part Number, MIN , ESN and SCM automatically transmitted] Validation Procedure at MSC & Voice-Frequency pair Allocation Base Station Pages the Information for the Mobile MSC Connects the Mobile with the Called Party[Another Mobile/Landline Phone] Call is Established and Communication Starts

Cellular Mobile Communications-I An Introduction

 Call Setup Procedure (Cont’d) 3. Receives a Call Initiation Request from Base Station, and Verifies that User has a Valid MIN & ESN pair

MSC

4. Locates the

7. Connects the

Called Party, Allocates a VFPs and Instructs the Base Stations via FCC

Called Party[on PSTN]/Mobile to the Mobile

5. Pages for the Called Mobile, the Mobiles are instructed to move to the Allocated VFPs respectively

FCC

Base Station

RCC

2. Receives a Call Initiation Request, with MIN, ESN, SCM and Called Part Number 8. Begins Voice

FVC

Transmission

8. Begins Voice

RVC

Reception

6. Receives [Called Mobile] the Page and Matches the MIN, the Mobiles get ready to move to the respective Allocated VFPs

FCC

Mobile

1. Makes a Call Initiation RCC

Request, with MIN and Called Part Number

8. Begins Voice

FVC

Reception

8. Begins Voice

RVC

Transmission TIME

Cellular Mobile Communications-I An Introduction

 Handoff and Roaming Handoff When a Mobile is on the edge of a Cell RSL of the Mobile in that Cell gets bellow a set Level Base Station of the Cell originates a Handoff request MSC gets RSL Info from all the Candidate Cells MSC asks the Originating Cell and the Strongest Candidate Cell to Coordinate In Case the Handoff is Successful, the Mobile is asked to switch to another VFP All this happens in a matter of seconds and you hear a little CLICK sound

Roaming When SID of the Control Channel and that programmed in the Mobile does not match: The Mobile is in another Service Provider’s Area MSC of the Cell contacts the MSC of the Mobile’s Home System After Verification, if the Mobile is Allowed, the new MSC is ready to Serve.

MSC

Cellular Mobile Communications-I An Introduction

 Comparison of Common Wireless Communication Systems

Comparison of Mobile Communication Systems - Mobile/Base Station System

Coverage Range

Required InfraStructure

Complexity

Hardware Cost

Carrier Frequency

Functionality

Tv Remote Control

Low

Low

Low

Low

Infra-Red

Tx/Rx

Garage Door Contol

Low

Low

Low

Low

<100 Mhz

Tx/Rx

Paging System

High

High

Low/High

Low/High

<1GHz

Rx/Tx

Cordless Phone

Low

Low

Moderate/Low

Low/Moderate

<100 MHz

Transceiver

Cellular Phone

High

High

High

Moderate/High

<1 GHz

Transceiver

Tx = Transmitter

Rx = Receiver

Cellular Mobile Communications-I An Introduction

 Cellular Mobile Access Technologies FDMA

Assigns each Call a Separate Frequency

Works like Radio Stations Mainly Analogue Technology-used by AMPS, NAMPS, E-TACS, NMT-450, JTACS Not an Efficient Method for Digital Transmission

849 MHz

869 MHz

Cellular Mobile Communications-I An Introduction

 Cellular Mobile Access Technologies TDMA

Assigns each Call a certain Time-Slot on a Designated Frequency Each Mobile/User gets one-third of a total Channel Time-Slot[6.7 ms] Courtesy of Compression Techniques: Speech Data in Digital Form takes considerably less time Optimal Frequency Usage: System Capacity improves by three times Operates both in 800 MHz[IS-54] and 1900 MHz[IS-136] Digital Access Technology use by GSM, USDC, IDEN, PDC and PCS

Cellular Mobile Communications-I An Introduction

 Cellular Mobile Access Technologies CDMA

Assigns a Unique Code to each Call and Spreads it over the entire bandwidth available  A form of Spread Spectrum Technology Speech Data is sent in small pieces over number of Discrete Frequencies available at any time in a specified range  Receiver uses the same unique Code to Recover the Speech Data GPS used for Exact Time Stamp Can handle 8-10 Calls in the same Channel Space as one Analogue Channel An Access Technology for 3G Mobile Systems[IMT-2000] Supports both Bands [800 MHz and 1900 MHz]

Cellular Mobile Communications-I An Introduction

 Cellular System vs. Personal Communication System/Network (PCS/PCN)

 Personal Communication Services [PCS] is a system, very similar to Cellular Phone Service with great emphasis on personal services (such as Paging, Caller ID, and E-mail] and mobility  Originated in UK, to improve its competitiveness in the field  PCS has smaller Cell size, therefore, requires more infrastructure  PCS works in 1.85-1.99 GHz band  PCS uses TDMA Technology but with 200 KHz Channel Bandwidth with eight time-slots[as compared to 30 KHz and 3 time-slots used by Digital Cellular Phone System IS54/IS-136]  GSM and Cellular Digital Packet Data[CDPD] also use PCS

Cellular Mobile Communications-I An Introduction

 Dual Band/Dual Mode Cellular Phones Dual Band Phone:

Supports both bands 800 MHz

and 1900 MHz

Dual Mode Phone: Access

Supports both FDMA and TDMA

Technologies

Dual Band/Dual Mode Phone: Supports both Bands and Both Access Technologies

Tri-Mode Phone: It can Support FDMA/TDMA/CDMA all Access Tech. A popular version of Tri-Mode Cellular Phone is the one which supports GSM [800 MHz as well as 1900 MHz (USA version)] as well as FDMA.

Cellular Mobile Communications-I An Introduction

 Trends in Cellular radio and Personal Communications

 PCS/PCN: PCS calls for more personalized services whereas PCN refers to Wireless Networking Concept-any person, anywhere, anytime can make a call using PC. PCS and PCN terms are sometime used interchangeably  IEEE 802.11: A standard for computer communications using wireless links[inside building].  ETSI’s 20 Mbps HIPER LAN: Standard for indoor Wireless Networks  IMT-2000 [International Mobile Telephone-2000 Standard]: A 3G universal, multi-function, globally compatible Digital Mobile Radio Standard is in making  Satellite-based Cellular Phone Systems  A very good Chance for Developing Nations to Improve their Communication Networks

Cellular Mobile Communications-I An Introduction

 Important First Generation Analog Systems Type

AMPS

ETACS

NTT

Region

America

Europe

Japan

Multiple access Duplexing

FDMA

FDMA

FDMA

FDD

FDD

FDD

Forward band

869 - 894 MHz

935 – 960 MHz

870 – 885 MHz

Reverse band

824 – 849 MHz

890 – 915 MHz

925 – 940 MHz

Channel spacing No. of channels

30 KHz

25 KHz

25 KHz

831

1000

600

Cellular Mobile Communications-I An Introduction

 Important Second Generation Digital Systems Type

IS-54

IS-95

GSM

PDC

Region

America

America

Europe

Japan

Multiple access /Duplexing Modulation

TDMA/FDD

CDMA/FDD

TDMA/FDD

TDMA/FDD

π/4 DQPSK

QPSK/OQPSK

GMSK

π/4 DQPSK

Forward Band

869 - 894 MHz 824 – 849 MHz 30 KHz

869 - 894 MHz 824 – 849 MHz 1.25 MHz

935 – 960 MHz 890 – 915 MHz 200 KHz

810 – 826 MHz 940 – 956 MHz 25 KHz

Reverse Band

Channel Spacing Data/chip Rate 48.6 Kbps

1.2288 Mcps

Codec Rate Kbps

7.95

270.833 Kbps 1.2/2.4/4.8/9. 13.4 6

Users/channel

3

Up to 55

8

42 Kbps

3

6.7

Cellular Mobile Communications-I An Introduction

 Difference Between First & Second Generation Systems

Traffic Channels – 1G systems use analog FM

modulation; 2G systems use low bit-rate voice coding and digital transmission Channel Access – 2G systems allow each frequency channel to be shared by a number of users, using TDMA or CDMA techniques Error Detection and Correction – 2G digital traffic channels incorporate FEC for error detection and correction, giving higher power and bandwidth efficiency Encryption – all 2G systems provide encryption to prevent eavesdropping

Cellular Mobile Communications-I An Introduction

 World-wide Subscriber Base as a Function of Technology (June 2006)

Cellular Mobile Communications-I An Introduction

 GSM (Global System for Mobile)  « Groupe Special Mobile » later changed to « Global System for Mobile »

 Developed by ETSI as a pan-European 2G mobile standard  Standard activity started in 1982, deployed in 1992  A complete system standard for ISDN-like mobile services    

Time division multiple access (8 users per 200KHz) 900 MHz band; later extended to 1800MHz Added 1900 MHz (US PCS bands) GSM is dominant world standard today

•Well defined interfaces; many competitors •Tri-band GSM phone can roam the world today

Cellular Mobile Communications-I An Introduction

 GSM Growth – From 1993 to June 2006

Cellular Mobile Communications-I An Introduction

 North American Standards Published by the Telecommunications Industry Association (TIA) as “Interim Standards” (IS) 2G air interface standards (PCS) include IS-54/136 – TDMA over 30 KHz channels IS-95 – CDMA standard developed by Qualcomm in 1991 and adopted by TIA in 1993

IS-634 standard for MSC-BSC interface IS-41 standard for MSC-MSC interface Services, interoperability, compatibility and performance issues are addressed by TR-45/46 committees TR-45/46 reference model is similar to the GSM architectural model

Cellular Mobile Communications-I An Introduction

 Properties of CDMA Cellular Frequency Diversity – frequency-dependent transmission impairments have less effect on wide-band signal Multipath Resistance – can use RAKE receiver to coherently combine multipath signals Privacy – privacy is inherent since spread spectrum is obtained by use of noise-like signals Graceful Degradation – system only gradually degrades as more users access the system Soft Handoff – mobile acquires new cell before disconnecting from the old; diversity combining of signals from the two cells enhance performance Near-far Problem – without power control, signals from MS closer to the BS will overwhelm signals from MS farther away

Cellular Mobile Communications-I An Introduction

 Problems with CDMA Cellular  Self-Jamming – arriving transmissions from multiple users not aligned on chip boundaries unless users are perfectly synchronized  Near-far Problem – signals closer to the receiver are received with less attenuation than signals farther away  Soft Handoff – requires that the mobile acquires the new cell before it relinquishes the old; this is more complex than hard handoff used in FDMA and TDMA schemes

Cellular Mobile Communications-I An Introduction

 1G and 2G – Voice Centric Systems Cellular coverage is designed for voice service Area outage, e.g. < 10% or < 5%. Minimal, but equal, service everywhere Cellular systems are designed for voice 20 ms framing structure Strong FEC, interleaving and decoding delays Spectral Efficiency around 0.04-0.07 bps/Hz/sector comparable for TDMA and CDMA

Cellular Mobile Communications-I An Introduction

 3G Vision –Multimedia (Voice, Data, and Video) Universal global roaming Multimedia (voice, data & video) Increased data rates 384 kbps while moving 2 Mbps when stationary at specific locations

Increased capacity (more spectrally efficient) IP architecture Problems No killer application for wireless data as yet Vendor-driven

Cellular Mobile Communications-I An Introduction

 Standardization Bodies ITU (International Telecommunication Union) Radio standards and spectrum

IMT-2000 ITU’s umbrella name for 3G which stands for International Mobile Telecommunications 2000

National and regional standards bodies are collaborating in 3G partnership projects ARIB, TIA, TTA, TTC, CWTS. T1, ETSI

3G Partnership Projects (3GPP & 3GPP2) Focused on evolution of access and core networks

Cellular Mobile Communications-I An Introduction

 IMT-2000 Vision-Integration of Services and Networks

Global Satellite Suburban

Macrocell

Urban

Microcell

Basic Terminal PDA Terminal Audio/Visual Terminal

In-Building

Picocell

Cellular Mobile Communications-I An Introduction

 IMT-2000 Radio Standards IMT-SC* Single Carrier (UWC-136): EDGE GSM evolution (TDMA); 200 KHz channels; sometimes called “2.75G”

IMT-MC* Multi Carrier CDMA: CDMA2000 Evolution of IS-95 CDMA, i.e. cdmaOne

IMT-DS* Direct Spread CDMA: W-CDMA New from 3GPP; UTRAN FDD

IMT-TC** Time Code CDMA New from 3GPP; UTRAN TDD New from China; TD-SCDMA

IMT-FT** FDMA/TDMA (DECT legacy)

Cellular Mobile Communications-I An Introduction

 Cellular Network Evolution Path

3G

2.75G Intermediate Multimedia

2.5G 2G

Multimedia

Packet Data

Digital Voice

1G Analog Voice

GPRS

GSM

EDGE

W-CDMA (UMTS)

384 Kbps

Up to 2 Mbps

115 Kbps

NMT

9.6 Kbps

GSM/ GPRS

TD-SCDMA

(Overlay) 115 Kbps

2 Mbps?

TDMA TACS

9.6 Kbps

iDEN 9.6 Kbps

iDEN PDC

(Overlay)

9.6 Kbps

AMPS

CDMA 1xRTT

CDMA

PHS

1984 - 1996+

14.4 Kbps / 64 Kbps

1992 - 2000+

PHS (IP-Based)

144 Kbps

64 Kbps

2001+

2003+

cdma2000 1X-EV-DV Over 2.4 Mbps

2003 - 2004+ Source: U.S. Bancorp Piper Jaffray

Cellular Mobile Communications-I An Introduction

 Cellular Network Evolution Path-2 First Generation

Mobile Telephone Service

Analog Cellular Technology Macrocellular Technology

Second Generation

Third Generation

Fourth Generation

Advanced Wireless Voice Services

Integrated Voice/Data & Wireless/Wireline

Tele-Presenting

Wireless Data Services

Multimedia Services

Digital Cellular Technology

Broader Bandwidth Channels with High Spectrum Efficiency

Microcellular & Picocellular Technologies Wireless Intelligent Network

Mid-80s NMT TACS Analog AMPS

Mid-90s GSM IS-54/ 136 TDMA IS-95/ cdmaOne PDC DECT

Location Services

Advanced Network/Software Architectures Advanced Coding & Signal Processing Techniques Intelligent Antennas

Distance Learning Intelligent Agent Services

?

Knowledge-Based Network Operations Unified Service Networks

Wideband Radios

Year 2000+ W-CDMA UWC-136 cdma2000

Year 2010 ?

Source: IEEE Communications Magazine

Cellular Mobile Communications-I An Introduction

 High Speed Circuit Switched Data (HSCSD) for 2.5G GSM

Part of GSM Phase 2 development Use dedicated TDMA time slots for circuit switched data Each time slot yields a data rate of 14.4 Kbps Up to 4 time slots can be used for a data rate up to 57.6 Kbps HSCSD connection using multiple time slots can be pre-empted by voice calls to give up the extra slots Suitable for streaming data applications such as digital audio/video Inefficient for applications with bursty data traffic, such as Web surfing The service is not widely supported

Cellular Mobile Communications-I An Introduction

 General Packet Radio Service (GPRS) for 2.5G GSM

Part of GSM Phase 2 development Also supported by IS-136 TDMA in N. America Use shared TDMA time slots for packet switched data MS uses a reservation MAC protocol to indicate needs for data bandwidth to BSC which schedules reserved time slots for the MS Up to 8 time slots can be used for a data rate up to 171.2 Kbps; in practice MS’s are not assigned 8 time slots GPRS using multiple time slots can be pre-empted by HSCSD or voice calls to give up the extra slots Much more efficient for applications with bursty data traffic, such as Web surfing

Cellular Mobile Communications-I An Introduction

 Enhanced Data rates for GSM Evolution (EDGE) for 2.5G GSM

Provides an evolution path from existing GSM/TDMA standards to deliver 3G services in existing spectrum bands Reuses GSM carrier bandwidth and time slot structure Can be introduced in GSM using a minimum of only one time slot per BS Reuse of existing GSM and TDMA/IS-136 infrastructure Can be deployed using as little as 600 kHz of total bandwidth 384 Kbps data capability to satisfy the IMT-2000 requirements for pedestrian (microcell) and low speed vehicular (macrocell) environments 144 Kbps data capability for high speed vehicular environment

Cellular Mobile Communications-I An Introduction

 3G WCDMA (UMTS) – Pros and Cons Wideband CDMA Standard for Universal Mobile Telephone Service (UMTS)

Committed standard for Europe and likely migration path for other GSM operators Leverages GSM’s dominant position

Requires substantial new spectrum 5 MHz each way (symmetric)

Legally mandated in Europe and elsewhere Sales of new spectrum completed in Europe At prices that now seem exorbitant

Cellular Mobile Communications-I An Introduction

 3G cdma2000 Specification developed by the Third Generation Partnership Project 2 (3GPP2) CDMA 2000 1x currently deployed as 2.5G overlay on IS 95 systems 1.25 MHz channel bandwidth same as IS 95 max data rate 144 Kbps now increasing to 307 Kbps in the future

CDMA 2000 1xEV (evolution using 1x channel bandwidth) 1xEV-DO data only, 384 Kbps - 2.4 Mbps max 1xEV-DV for data and voice, specified by 2003/4, up to 4.8 Mbps

CDMA 2000 3x uses 3x1.25 MHz bandwidth, 2-4 Mbps CDMA 2000 1x EV-DO and CDMA 2000 3x are ITU approved, IMT-2000 (3G) standards

Cellular Mobile Communications-I An Introduction

 3G cdma2000 – Pros and Cons Evolution from original Qualcomm CDMA Now known as cdmaOne or IS-95

Better migration story from 2G to 3G cdmaOne operators don’t need additional spectrum 1xEVD0 promises higher data rates than UMTS, i.e. W-CDMA

Better spectral efficiency than W-CDMA(?) Arguable (and argued!)

CDMA2000 core network less mature cmdaOne interfaces were vendor-specific Hopefully CDMA2000 vendors will comply w/ 3GPP2

Cellular Mobile Communications-I An Introduction

 3G TD-SCDMA (Time-Division, Synchronous CDMA) Time division duplex (TDD) Chinese development Will be deployed in China

Good match for asymmetrical traffic! Single spectral band (1.6 MHz) possible Costs relatively low Handset smaller and may cost less Power consumption lower TDD has the highest spectrum efficiency

Power amplifiers must be very linear Relatively hard to meet specifications

Cellular Mobile Communications-I An Introduction

 Major 3G Standardization Bodies and Forums Standard Organization International Telecommunications Union (ITU) European Telecommunications Standard Institute (ETSI) Telecommunications Industry Association (TIA) Association of Radio Industries and Business (ARIB) American National Standard Institute (committee T1P1)

Region International Europe North America Japan North America

Cellular Mobile Communications-I An Introduction

 Major 3G Standardization Bodies and Forums-Cont’d 3rd Generation Partnership Project (3GPP) Focus on setting global standard for UMTS Terrestrial Radio Access (UTRA) Involve ETSI (Europe), ARIB (Japan), T1P1 (USA), etc.

3rd Generation Partnership Project 2 (3GPP2) Focus on setting global standard for cdma2000 More of a N. American focus

Cellular Mobile Communications-I An Introduction

 UTRA Parameters Official name Uplink frequency Downlink frequency Carrier spacing Duplex scheme Chip rate Modulation Frame length Time slots/frame

UTRA FDD IMT-DS 1920 - 1980 MHz 2110 - 2170 MHz 5 MHz FDD 3.84 Mcps QPSK 10 ms N/A

UTRA TDD IMT-TC 2010 - 2025 MHz 2010 - 2025 MHz 5 MHz TDD 3.84 Mcps QPSK 10 ms 15

Cellular Mobile Communications-I An Introduction

 Mobile Wireless Spectrum Bands (MHz)

Frequencies (MHz)

450 480 800 900 1500 1700 1800 1900

450-467 478-496 824-894 880-960

2100 2500

1750-1870 1710-1880 1850-1990 1885-2025 & 2100-2200 2500-2690

Regions Europe Europe America Europe/APAC Japan PDC Korea Europe/APAC America Europe/APAC ITU Proposal

GSM/ EDGE WCDMA CDMA2000 x x x x

x x

x

x x

x x x x x x

x

x x

Cellular Mobile Communications-I An Introduction

 Prospectus for Global Roaming Multiple vocoders (AMR, EVRC, SMV,…) Six or more spectral bands 800, 900, 1800, 1900, 2100, 2500, …? MHz

At least four modulation variants GSM (TDMA), W-CDMA, CDMA2000, TD-SCMDA

The handset approach Advanced silicon Software defined radio Improved batteries

Cellular Mobile Communications-I An Introduction

 Biggest Threats to Today’s 3G-Wireless LANs Faster than 3G 11 or 56 Mbps vs. <2 Mbps for 3G when stationary

Data experience matches the Internet With the added convenience of mobile Same user interface (doesn’t rely on small screens) Same programs, files, applications, Websites.

Low cost, low barriers to entry Organizations can build own networks Like the Internet, will grow virally

Opportunity for entrepreneurs! Opportunity for wireless operators?

Cellular Mobile Communications-I An Introduction

 Wireless Local Area Networks (WLANs)

Cellular Mobile Communications-I An Introduction

 Wireless LAN Standards

Cellular Mobile Communications-I An Introduction

 Bluetooth

Cellular Mobile Communications-I An Introduction

 Ultra-Wideband Radio (UWB)

Cellular Mobile Communications-I An Introduction

 Why UWB is more Interesting?

Cellular Mobile Communications-I An Introduction

 IEEE 820.15.4 (ZigBee Radios)

Cellular Mobile Communications-I An Introduction

 WLANs Data Rates

Cellular Mobile Communications-I An Introduction

 WLANs Range

Cellular Mobile Communications-I An Introduction

 WLANs Power Dissipation

Cellular Mobile Communications-I An Introduction

 Technology Trends Improvements in system capacity through advanced signaling, detection and signal processing techniques: Orthogonal frequency division multiplexing OFDM Turbo coding Multiple-user detection (interference cancellation) Multiple-input multiple-output (MIMO) processing Software radio Improvements in features and capabilities for better services: Full integration into the Internet for multimedia services Seamless roaming between cellular, wireless LAN, and satellite networks

Cellular Mobile Communications-I An Introduction

 Beyond 3G?  Need to provide: “beyond data”

Higher data rates (at least on downlink) More multimedia contents

Voice, data, video, WWW access. broadcast as well as cellular

Wideband (10 MHz or more)

 Main Candidates

WOFDM WCDMA Multi-Carrier CDMA Other???

 How will these systems access the Internet and coexist with wireless LANs?

Cellular Mobile Communications-I An Introduction

 In Short … Wireless data and multimedia are the main

drivers for future generations of cellular systems

Several competing standards (as in 2G) Evolutionary path unclear Killer application unknown What do mobile users want?

Will wireless LANs or cellular systems

dominate the future wireless data landscape?