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Third Generation Wireless Systems. 3G Wireless. Dr. Roshdy H.M. Hafez. email: hafez@sce.carleton.ca. 3G Wireless. Course Outline. Motivation for 3G IMT-2000 Development Procedure Fundamental Technical Issues Emerging 3G standards Wireless Internet Broadband Wireless Access
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Third Generation Wireless Systems 3G Wireless
Dr. Roshdy H.M. Hafez email: hafez@sce.carleton.ca
3G Wireless Course Outline Motivation for 3G IMT-2000 Development Procedure Fundamental Technical Issues Emerging 3G standards Wireless Internet Broadband Wireless Access Future Trends
Motivation for 3G • The second generation (2G) wireless systems • Motivations and drives for new standards • The business case for 3G • The case for broadband fixed wireless access
indoor Data Rate • Hiper LAN • Ad-Hoc Networks • AT&T • Olivetti • IEEE802.11 • … etc .. Wireless LAN 10 Mbps • GSM • IS-136 (D-AMPS) • IS-95 (CDMA) 10 kbps PCS Cellular Cell Size Outdoor Second Generation Systems (2G)
2G Services • Voice • The main service • Systems and designed and optimized for voice communications • Huge market • The main drive for the entire industry • Data • Limited data applications • Circuit-switched • Short Message Systems (SMS) • The main drive for 3G 1 Mega byte $ 5 1 Mega byte $ 1,000
The three Dominant Standards 30 kHz NA-TDMA 200 kHz GSM 1.25 MHz CDMA Frequency
800 707 700 600 474 500 Subscription in Millions 400 307 300 204 138 200 87 5.5 3.4 2.3 100 0 0 1992 1993 1994 1995 1996 1997 1998 1999 2000 Year World-Wide Use of 2G Systems others 190 TDMA CDMA 71 GSM 440 Source: http://www.gsmworld.com/
70,000,000 60,000,000 50,000,000 40,000,000 30,000,000 20,000,000 10,000,000 Sep.97 Dec.97 Mar 98 Jun. 98 Sep. 98 Dec. 98 Mar 99 Jun. 99 Sep. 99 Dec. 99 Mar 00 Jun. 00 Caribbean. Latin America North America CdmaOne Worldwide Subscription Asian Pacific Europe. Middle east. Africa Source: http://www.cdg.org/world/cdma_world_subscriber.html
OMC VLR MSC HLR PSTN EIR BS ISDN Mobile Stations Subscriber Services Base Stations & B.S. Controllers 2G Network Model Network Mgmt AuC BSC Authentication Center VLR = Visitor Location Registry HLR = Home Location Registry BS = Base Station OMC = Operation & Maintenance Center EIR = Equipment Identification Registry BSC = Base Station Controller MSC = Mobile Switching Center
BSC BSC IWF MSC 2G Network Model (cont.) modem PSTN Packet Or IP-Network
Basic 2G Voice Calls 64 kbps DS0 PSTN 64 kbps MSC Digital Switch Vocoder 8 -16 kbps BS BSC Coded voice data 8 -16 kbps
Example of 2G Voice Connection HLR VLR BSC MSC PSTN System A HLR VLR BSC MSC System B
MS BSS VLR VLR MSC MSC 2G Mobile Terminated Call HLR Wireless Signaling SS7 PSNT
Example of 2G Data Connection Public Data Network BSC MSC IWF UE MS RS-232 RLP Protocol HDLC FR PPP Protocol Application
Broadband Multimedia Wireless Multimedia PCS PCS Cellular 3G 2nd Generation IMT-2000 2.5 G 2G to 3G Evolution
HDR 2G to 3G Evolution (cont.) Cdma2000 IS-95 IS-95-B WCDMA GSM GPRS EDGE UWC-136 IS-136+ IS-136 2G 3G
Who is Doing What? GSM Association ETSI T1 UWCC TIA CDG Associations GSM TDMA IS-136 IS-95 2G 2.5G GPRS/EDGE 1XRTT HDR W-CDMA UWC-136 Cdma2000 3G 3G Harmonization Groups 3GPP UWCC 3GPP2
2G Limitations • Designed primarily for mobile telephony • Symmetric communications • Circuit-switched • Tolerate high error rates (up to 0.1%) • Narrowband information (< 14.4 kbps) • Too Many Standards • Several incompatible air interfaces (GSM, TDMA. CDMA, AMPS, DECT,…) • Wireless LANs and PCS are totally different and incompatible • Isolated Networks • Two different networks: IS-41-C and GSM-MAP • No direct communications between different operators
Goals of 3G • Wide range of operating wireless environments • Indoor / Outdoor • High mobility (vehicular) / low mobility • Wide range of transmission rates • 1.2 kbps - 2 Mbps • Support for different transmission modes • Circuit switched voice and data • IP-based application • Support for a wide range of services • Multimedia QoS control capabilities • Compatibility and inter-operability with 2G systems • Network interface standards
The Business Case for 3G • Viable Applications • E-Commerce • email • Internet browsing • Entertainment • Consumer Acceptance • Ease of use • Consumer dependency on Internet • Widespread acceptance of cellular technologies • Efficient Distribution • Integration with other devices • New car built-in options
The Business Case for 3G Corporate Applications & email Data Services & Information Databases WWW browsing Time Always-ON Pre-paid Wide-spread availability
Mobility • The term "Personal" implies "Mobility" • Mobility management and Signaling • Physical Limitations • Personal communication is more challenging • PCS antennas cannot be easily optimized • PCS environment is highly variable • Radio coverage • FWA requires targeted radio coverage • PCS requires total coverage • Market • PCS has much bigger market • Billions of potential subscribers How About Fixed Wireless Access PCS vs. FWA
The Business Case for FWA • Viable alternative to cable, direct-to-home satellite and xDSL access over copper • Easy to deploy with minimum infra-structure • Very attractive solution for building-to-building high speed data links
IMT-2000 Development Process • History of IMT-2000 within the ITU • The IMT-2000 guidelines • The RTT proposals and technical evaluations • The harmonization efforts 3GPP and GHG • IMT-2000 Spectrum Allocation
WRC 92 Race I FPLMTS Race II ACT 1997 UMTS IMT-2000 The Roots of IMT-2000 • IMT-2000 = 3G
A process to establish "Global Standards" for wireless communications • The IMT-2000 process addresses: • Air Interface • Networks • Services • It covers • Personal wireless (PCS) • Fixed Wireless Access (FWA) • Satellite What is IMT-2000? Air Interface Networks Services IMT-2000 PCS FWA Satellite
IMT-2000 Data Model Wired 100.0 10.0 WLAN 1.0 Bit rate Mb/s IMT-2000 0.1 CORDLESS CELLULAR 0.01 room building stationary walking car indoor outdoor
indoor Outdoor The IMT-2000 Three Environments Data Rate 10 Mbps Wireless LAN 2 Mbps Indoor 384 kbps Pedestrian 3G 144 kbps PCS/Cellular Vehicular Cell Size
ITU Request for candidate RTT proposals 1997 Development of RTT Proposals Self evaluation & Consensus building 1998 Proposals & Evaluation reports Examining proposed RTT Various Groups 1999 RTT Synthesis & Consensus building 3GPP 3GPP-2 Recommendation Implementation 2000 Developing Air Interface Standards
There are 15 proposals submitted to ITU: • 1 (indoor only) • 9 (indoor/outdoor) • 5 (satellite) • Out of the 9 indoor/outdoor proposals • 1 TDMA • 1 Hybrid TDMA/CDMA • 7 CDMA • The best known proposals were • Cdma2000 North American based on IS-95 • W-CDMA UTRA/ARIB Europe & Japan • UWC-136 GSM & IS-136 RTT Proposals
Harmonization • Global Partnerships: • 3GPP (3G Partnership Project) • 3GPP2 • UWCC (Universal Wireless Communications Consortium) • OHG (Operators Harmonization Group) • Convergence of the technology • Emergence of technology groupings
3G Partnership Project (3GPP) ITU International Recommendations High Level Frame Work 3GPP Regulators Project Coordination Group Partners Organizations Marketing Technical Specification Groups Individual Members Technical Contributions Technical Specifications
TSG-CN TSG-RAN TSG-SA TSG-T Core Network Radio Access Network Services and Systems Aspects Terminal 3GPP 3GPP Technical Specification Group
3GPP2 Steering Committee TSG-A TSG-N TSG-P A- Interface TSG-R TSG-S ANSI-41 WIN Packet Data Network Network Interface IS-41 Service and System Aspect TSG-C cdma2000 3GPP2
ITU - IMT-2000 WCDMA Cdma2000 UWC-136 DECT+ • 3GPP • -ETSI • ARIB • Korea TTA • China CWTS • 3GPP2 • -TIA • ARIB • Korea TTA • China CWTS • -ETSI • US TR45.3 • UWCC ETSI Partnership Supporting Organizations
IMT-2000 Spectrum Allocation • WRC-92 identified the spectrum requirements of IMT-2000 • The required spectrum was estimated at 230 MHz for both terrestrial and satellite segments. 1885 – 2025 & 2110 – 2170 MHz [Terrestrial] 1980 – 2010 & 2170 – 2200 MHz [Satellite] • Subsequence decision in WARC-97 led to some modifications in region 2
US Spectrum Use Near 2 GHz Spectrum Identified by ITU for IMT-2000 Near 2 GHz WRC-2000 175 140 90 WARC-92 1700 1750 1800 1850 1900 1950 2000 2050 2100 2150 2200 MHz European Spectrum Use Near 2 GHz GSM-1800 Mobile GSM-1800 Base Other 20 20 85 Other Satellite 30 30 Unpaired UMTS UMTS Mobile 15 UMTS 20 60 60 UMTS Base GSM-1800 75 75 DECT MSS Uplink 1700 1750 1800 1850 1900 1950 2000 2050 2100 2150 2200 MHz MSS Downlink US Spectrum Use Near 2GHz PCS Mobile 10 PCS Unlic Other 95 85 PCS Base 35 Satellite 35 Prop. Adv. Srvc . MSS Uplink Advanced 45 40 5 MSS Downlink 60 PCS 60 20 Govt Govt/ Bcast Aux 1700 1750 1800 1850 1900 1950 2000 2050 2100 2150 2200 MDS MHz
WRC-2000 World Radio Communications 2000 Istanbul, Turkey May 8 – June 2, 2000 • WRC-2000 will consider allocating additional spectrum • Additional 160 MHz was designated for 3G
Fundamental Technical Issues • Radio Coverage • How Fast? How Far? • Interference and Frequency Re-Use • TDMA vs. CDMA • What do users want? • What do Service Providers want?
ch. #k ch. #m RADIO CELL • Different users within the radio cell use different physical channels: • Different frequencies: FDMA • Different frequencies and time slots: TDMA • Different codes: CDMA The Wireless Segment
Pref = constant x Ptransmit n varies between 2 and 4 Signal Decay with Distance weak signal strong signal Could be a huge difference 1 : 1000,000 Distance
How Far ? and How Fast ? The Signal-to-noise ratio should be large enough for reliable reception Interference Noise Signal Max. Distance • Higher data rates need proportionally higher signal-to-noise ratio • The maximum data rate that can be supported falls as the distance increases
Interference and Frequency Re-Use frequency re-use distance interference signal Two cells using the same frequency
1 1 4 2 3 3 6 5 5 7 1 7 4 1 1 4 2 3 2 6 6 5 7 1 1 The Basic Cellular Structure • Radio cells are divided into clusters. Each cluster consists of M adjacent cells (7 in AMPS). • The total available bandwidth is divided into N physical channels • The N channels are divided into M groups. Each cell in a cluster gets one of the M frequency groups.