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Cellular Wireless Communication: Past Present and the FuturePast, Present and the Future

d b S d il Sh hPresented by: Syed Ismail Shah

E-mail: ismail@iqraisb.edu.pkismail@3gca.org@ g g

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Outline1) Introduction to Mobile Communication and First

Generation Systems2) Digital Communication and the 2G Systems3) The 2.5G systems4) Third Generation Systems5) Wireless Local Loop6) O h Wi l S6) Other Wireless Systems7) IMT-Advanced (4G)8) Wi l O t i P ki t8) Wireless Operators in Pakistan9) Some Recommendations

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Why Mobile Communication?Question: Why do we need a new technology when

h h d l d bli l h k

Why Mobile Communication?

we have such a developed public telephone network.

Answer: Mobility.

Confinement Versus Freedom

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Challenges of MobilityChallenges of using a radio channel:

The use of radio channels necessitates methods of sharing them –gchannel access. (FDMA, TDMA, CDMA)

The wireless channel – poses a more challenging problem than with wires.

Bandwidth: it is possible to add wires but not bandwidth. So it is important to develop technologies that provide for spectrum reuse.

Privacy and security - a more difficult issue than with wired phone.

Others: low energy (battery), hand off, roaming, etc.

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First Generation SystemsCellular concept emerges in early

1970s1970s.

Cellular technology allows frequency-reuse. With this we need to q yhave Handoff (handover)

In 1G we had analog voice but Control Link was digital

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Examples of First Generation Cellular Systems (FDMA based)

1) Advanced Mobile Phone System (AMPS)

2) Narrowband AMPS (NAMPS)

3) Nordic Mobile Telephone (NAMPS)3) Nordic Mobile Telephone (NAMPS)

4) European Total Access System (ETACS)

5) Japanese TACS (JTACS)5) Japanese TACS (JTACS)

6) Nippon Telephone and Telegram (NTT)

7) Cordless Telephone 2 (CT2)

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First Generation – AMPS and European Total Access CellularEuropean Total Access Cellular

System (ETACS) Parameter AMPS ETACS

Multiple Access FDMA FDMA

Duplexing FDD FDD

Channel Bandwidth 30kHz 25kHz

Traffic Channel per RF Channel 1 1

Reverse Channel Frequency 824 – 849 MHz 890 – 915 MHzReverse Channel Frequency 824 849 MHz 890 915 MHz

Forward Channel Frequency 869 – 894 MHz 935 – 960 MHz

Voice Modulation FM FM

Peak Deviation: Voice Channels ± 12 kHz ± 10 kHzControl/Wideband Data ± 8 kHz ± 6.4 kHz

Channel Coding for Data Transmission

BCH(40,28) on FC/BCH(48,36) on RC

BCH(40,28) on FC/BCH(48,36) on RC

Data Rate on Control channel 10kbps 8kbps

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Spectral Efficiency 0.33 bps/Hz 0.33 bps/Hz

Number of Channels 832 1000

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Digital Communication: TransmitterFrom Other

1 0 1 0 0 1 0Analog to

DigitalSource

1 0 1 1 0

Encrypt

0 1 1 0 1

Multiplex

From OtherChannels

Analog input

Digital Converter Bits Encoded

Bits

Encode EncryptEncrypted

Data

p

0 1 1 0 1

0 1 0 1 0Multiplexed

Pulse modulated

fDigital Bandpass

waveform

0 1 0 1 0

1 0 1 0 1Data

Channel Encoded

D t

Scrambled data

Bit to Sym. & Pulse

Modulate

waveformwaveformBandpass modulate

Channel Encode

Data

1 0 0 1 1 0 1

Scrambler

1 0 0 0 1

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1 0 0 0 1

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Digital Communication:Digital Communication: Receiver

Equalizer, Timing and

Bits

De-modulate

Digital Baseband waveform

Digital Bandpass waveform

Channel

Channel Decoded

DataDe-scrambleTiming and

Sym. to BitsDecode

0 1 1 0 1

Descrambled

D t dSource De-

Descrambled Bits 1 0 0 0 1

Decrypted Bits

1 0 1 1 0 DecryptAnalog

output

D/A

Decoded Bits

1 0 1 0 0 1 0

Source Decode De-

Multiplex

De-multiplexed

Bits

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output 1 0 1 0 0 1 0To other Channels

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Performance Metrics• Analog Communication SystemsAnalog Communication Systems

– Metric is fidelity: want m(t)≈m(t)– SNR typically used as performance metric

^

SNR typically used as performance metric

• Digital Communication Systems– Metrics are data rate (R bps) and probability of

bit error (Pb=p(b≠b))^

– Symbols already known at the receiver– Without noise/distortion/sync. problem, we will

10never make bit errors

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Second Generation Cellular Systems (TDMA and CDMA

based)1) GSM (Global System for Mobile)

2) PDC (Personal Digital Cellular)) ( g )

3) PHS (Personal Handy System)

4) DAMPS (Digital AMPS)4) DAMPS (Digital AMPS)

5) CDMAone (IS-95)

6) P l C i i S (PCS) 19006) Personal Communication System (PCS)-1900 (IS-136)

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Second Generation –Second Generation IS136/CDMA/GSM

Parameter IS-136 IS-95 GSM

Multiple Access TDMA/FDD CDMA/FDD TDMA/FDD

Modulation π/4 DQPSK BPSK GMSK

Channel Bandwidth 30 kHz 1.25 MHz 200 kHz

Reverse Channel Frequency Band

824 – 849 MHz1.85 – 1.99 GHz

824 – 849 MHz1.85 – 1.99 GHz

890 – 915 MHz1.85 – 1.99 GHz

Forward Channel 869 894 MHz 869 894 MHz 935 960 MHzForward Channel Frequency Band

869 – 894 MHz1.85 – 1.99 GHz

869 – 894 MHz1.85 – 1.99 GHz

935 – 960 MHz1.85 – 1.99 GHz

Channel Data Rate 48.6 kbps 1.2288 Mcps 270.83 kbps

Carrier Spacing 30 kHz 1.25 MHz 200 KHz

Speech Coding VSELP(Vector Sum excited linear prediction)

CELP RPE-LTP

Users per carrier 3 variable 8

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Second Generation –BenefitsHigher Capacity, Mobility

Easy frequency planning MAHO (Soft Handoff in CDMA)

-Dynamic Channel Allocation (GSM)

)

Error correction

FEC-Single Frequency Band (CDMA)

-FEC

-Interleaving

Better performance

-Low dropped call rate

Value-added Services

-SMS

13-Faster switching -Limited data

transmission capabilities

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Second Generation - Success

Four operational digital cellular technology: Dec’ 2000

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Four operational digital cellular technology: Dec’ 2000Source: EMC Database

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Evolution to 2 5G Mobile RadioEvolution to 2.5G Mobile Radio Networks (data-centric)

1. High speed circuit switched data (HSCSD): GSM

2. GPRS for 2.5G GSM and IS-136

3 EDGE for 2 5G GSM and IS 1363. EDGE for 2.5G GSM and IS-136

4. IS95B and CDMA2000 1x

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General Packet Radio Service (GPRS)General Packet Radio Service (GPRS)

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Enhanced Data for Global Evolution (EDGE)Enhanced Data for Global Evolution (EDGE)• EDGE uses 8PSK as opposed to GMSK as a modulation scheme. Essentially squeezing in more data in the available bandwidth.• Data rates closer to 3G. Intended to be used by operators who don’t have a 3G license but wish to deliver higherwho don t have a 3G license but wish to deliver higher data rates.• Requires all the radio cards in the existing GSM/GPRS network to be replaced.• Expensive solution to obtain similar data rates to the lowest expected 3G performance.lowest expected 3G performance.• Raw data rate using one GSM carrier can go up to 547.2 kbps (practical 384 kbps)

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IS 95 B and CDMA2000 1xIS 95 B and CDMA2000 1x• The 2.5 G Evolution of IS95 A.• Uses extra codes for increased data rates• Data Rates upto 115.2 kbps• Easy upgrade to CDMA2000• Intermediate steps to 3G:Intermediate steps to 3G:

– CDMA2000 1x, Release 0: Data rates of up to 153 6kbps153.6kbps

– CDMA2000 1x, Release A: Data rates of up to 307.2 kbps

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307.2 kbps

Iqra University IUIMT-2000 (3G)

• The International Telecommunications Union (ITU)defined the key requirements for International Mobile Telecommunications 2000 (IMT-2000) services.

• These requirements were that the system should supportdata rates of:

• 2 Mbps in fixed or in-building environments• 384 kbps in pedestrian or urban environments•144 kbps in wide area mobile environments•144 kbps in wide area mobile environments

• IMT-2000 is more commonly known as… 3G.

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2000 2001 2002 2003

Japan PDC W-CDMA

Europe

America

GSM

AMPS/D AMPS D AMPS

GPRS EDGE

HSCSD

America AMPS/D-AMPS

IS-95A IS-95B

D-AMPS

CDMA2000

2G System

3G System

Easy upgradeUpgrade requiring new modulationUpgrade requiring entire new radio system

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Universal Frequency ReuseUniversal Frequency ReuseUniversal Frequency ReuseUniversal Frequency ReuseFrequency

Reuse Factor = 7 for AMPSFrequency

Reuse Factor = 7 for AMPSCDMA UniversalF RCDMA UniversalF R

CC

B D AA

A A

Reuse Factor = 7 for AMPSReuse Factor = 7 for AMPS

CB D

Frequency ReuseFrequency Reuse

CB D

G EA

B D

FG E

A AA A

A

A A

A AA

B D

EA

FG

AF

G EC

B DA

FA

A AA

A A

AF A

FG E

A

AA A

A

21Frequency Reuse Factor = 4 for

TDMA systems

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CDMA2000 E l ti f 1 RTT t• Evolution of 1x RTT concept• High data rate service which is compatible to IS

9595• 1x EVDO: Evolution of the 1x system data

optimizedp• As in 1x-RTT technology utilizes 1.25 MHz of

band• System requires a separate carrier for the data• 2.4 Mbps forward link, 153.3 kbps reverse link• Rev. A: Support for VoIP: 3.1 Mbps FL, 1.8

Mbps RL• New revisions: B and other enhancement

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• New revisions: B and other enhancement

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3G W-CDMA (UMTS)3G W CDMA (UMTS)

• High Speed Downlink Packet Access (HSDPA)23

• High-Speed Downlink Packet Access (HSDPA)• HSUPA and HSPA, HSPA+ Phase 1 and 2

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TD-SCDMA

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Timeline: For UMTS and CDMA2000Timeline: For UMTS and CDMA2000

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5) Wireless Local Loop

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WIRELESS LOCAL LOOP• Definition: A telephone system where subscribers are

connected to the public switched telephone network p pusing radio signals rather than copper wire for part or all of the communication between the subscriber and the switchswitch.

• Countries with available elaborate telecommunication infrastructure used it to increase competition

C t i ith t il bl l b t t l i ti• Countries without available elaborate telecommunication infrastructure use it for efficient and feasible method of broadband delivery

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Some Countries using CDMA for WLLAlgeria, Azerbaijan, Bermuda, Brazil, Cambodia China Col mbia Dem Rep of

Some Countries using CDMA for WLL

Cambodia, China, Columbia, Dem. Rep. of Congo,Dominican Republic, Egypt, Ethiopia, Fiji G atemala Haiti India IndonesiaFiji, Guatemala, Haiti, India, IndonesiaKenya, Kuwait, Laos, Malaysia, Mauritius, M i M ld N l Ni i P ki tMexico, Moldova, Nepal, Nigeria, Pakistan, Poland, Puerto Rico, Romania, Russia, U d Uk i Vi t YUganda, Ukraine,Vietnam,Yemen

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6) Other Systems

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WIRELESS LOCAL AREA NETWORKS (WLANs)NETWORKS (WLANs)

• Network- group of two or more computer systems linked together. Local area networkssystems linked together. Local area networks are usually confined to one building.

• Wireless Fidelity (Wi-Fi)Wireless Fidelity (Wi Fi)– 802.11a (DS-SS) became standard (2Mpbs).– 802.11b is common (11Mbps) 2.4 GHz. Also has ( p )

the FH-SS extension.– 802.11g also uses the 2.4 GHz band. Data Rate: 54

b OMbps. Uses OFDM– 802.11n: Uses OFDM and MIMO

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Other Standards • Long Term Evolution

– Initial Deployment in the 700 MHz Frequency Band– Data Rate of tens of MbpsData Rate of tens of Mbps– Uses OFDM and MIMO

• Worldwide Interoperability for Microwave Access (WiMax)

Operate in the 2 5 3 5 or 5 8 GHz bands– Operate in the 2.5, 3.5, or 5.8 GHz bands.– Data Rates of tens of Mbps. – Versions: IEEE 802.16d and e with amendments like:

802.16f, g, h, i, j and k– Uses OFDM and MIMO

31• Variants of both are candidates for IMT-Advanced (4G)

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7) IMT-Advanced(4G)

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IMT-Advanced (4G)( )• The min requirements for peak spectral efficiencies

Downlink peak spectral efficiency is 15 bit/s/Hz– Downlink peak spectral efficiency is 15 bit/s/Hz– Uplink peak spectral efficiency is 6.75 bit/s/Hz.

• Six Proposals are under review

• Some are based on WiMax 802.16m and some on LTE

B h OFDM d MIMO• Both uses OFDM and MIMO

• Final Decision by October 201033

• Final Decision by October 2010

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IMT-Advanced (4G): Time-Line

Step1 and 2

No.1 No.2 No.3 No.4 No.5 No.6 No.7 No.8 No.9WP 5D meetings

2008 2009 2010No.10

2011

( )

Step1 and 2

Step 3(0)

(1)

(20 months)

Step 4(8 months)

(16 months) (2)Steps 5,6 and 7

(3)Steps 8

(20 months)

Steps in radio interface development process:(4)(12 months)

Step 1: Issuance of the circular letterStep 2: Development of candidate RITs and SRITsStep 3: Submission/Reception of the RIT and SRIT proposals

Step 5: Review and coordination of outside evaluation activitiesStep 6: Review to assess compliance with minimum requirementsStep 7: Consideration of evaluation results, consensus building

and acknowledgement of receiptStep 4: Evaluation of candidate RITs and SRITs

by evaluation groups

and decision Step 8: Development of radio interface Recommendation(s)

Critical milestones in radio interface development process:(0): Issue an invitation to propose RITs March 2008 (2): Cut off for evaluation report to ITU June 2010(1): ITU proposed cut off for submission October 2009

of candidate RIT and SRIT proposals(3): WP 5D decides framework and key October 2010

characteristics of IMT-Advanced RITs and SRITs(4): WP 5D completes development of radio February 2011

interface specification Recommendations IMT-Advanced A2-01

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Cellular Technology RoadmapCellular Technology Roadmap

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8) Wireless Operators in Pakistan

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Cellular Operators in PakistanCellular Operators in Pakistan1) Mobilink

Technology: GSM GPRS EDGE (WiMAx deployment:Technology: GSM, GPRS, EDGE (WiMAx deployment: Infinity)

2) UfoneTechnology: GSM, GPRS, EDGE

3) China Mobile Pakistan (CMPak, Paktel): ZongTechnology: EGSM GPRS EDGETechnology: EGSM, GPRS, EDGE

4) WaridTechnology: GSM, GPRS, EDGE (Associated company Wateen: WiMax)

5) TelenorTechnology: GSM GPRS EDGE

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Technology: GSM, GPRS, EDGE

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WLL OperatorsWLL Operators1) V-PTCLWirless

Technology: CDMA2000 EVDO Rev ATechnology: CDMA2000, EVDO Rev. A2) TeleCard

Technology: CDMA2000Technology: CDMA20003) WorldCall

Technology: CDMA2000, EVDO Rev. Aec o ogy: C 000, V O ev.4) Diallog (negotiation going on with World Call)

Technology: CDMA2000 1x, EVDO gy ,5) SCO

Technology: CDMA2000 1x, EVDO (?)

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L t t N (P ki t )Latest News (Pakistan)• Auction of 3G spectrum????????p• Only Mobile operators are eligible to bid ??• Three licenses to be issued??• Three licenses to be issued??• Possible (UMTS FDD Band I):

– 1920 to 1980 MHz (Up link)– 2110 to 2170 MHz (Down link)

• WiMax has been deployed

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Issues with widespread usage of wireless data

Why are new services/mobile content required?

Issues with widespread usage of wireless data

Tough competitionLow ARPUNo differentiation in Service OfferingsNo differentiation in Service Offerings

Problem:Wh t i ill diff ti t t f th th ?What services will differentiate one operator from the other?How would these services be delivered?

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Technologies

2G: Mainly Voice & SMS

2.5G: Limited Data Capability

3G and Beyond: High Speed Data coupled with data centric applications and services

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Ser ices E ol tion With Enriched User E periencesServices Evolution With Enriched User Experiences

Mobile TV

Wallpaper

Location BasedServices2D Gaming

Mobile TV

3D Gaming

Voice

Mobile Commerce

RingtonesMusic & Video

D d

Services Evolution

Paul,

Text Messaging MMS Blogging

on DemandPaul,How

did the meeting go?

Social Networking RSS Feeds & Tagging

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Send Options

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Some RecommendationsSome Recommendations• Appoint a minister ????????????• Need to expand our knowledge base• Need to expand our knowledge base• Human resource development (HRD)• Industry-university collaboration: HRD can be a• Industry-university collaboration: HRD can be a

starting point• Research: Both relevant like content development p

and not so immediately relevant to the current problems faced by the industry in Pakistan.T h l f h h li i• Technology transfer through government policies

• Involvement of the private sector in policy making

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making

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Thank You

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Thank You

For q estions/comments:For questions/comments:E-mail: ismail@iqraisb.edu.pkismail@3gca.org

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