WIMAX © 2005 H. H’mimyLecture 11, Slide 1SMU EE 8315 Advanced Topics in Wireless Communications - Spring’05 Southern Methodist University EETS 8315 / TC752-N Advanced Topics in Wireless Communications Spring Lecture 11: WIMAX Instructor: Dr. Hossam H’mimy, Ericsson Inc. (972)

WIMAX © 2005 H. H’mimyLecture 11, Slide 2SMU EE 8315 Advanced Topics in Wireless Communications - Spring’05 Announcement

WIMAX © 2005 H. H’mimyLecture 11, Slide 3SMU EE 8315 Advanced Topics in Wireless Communications - Spring’05 WiMAX forum The WiMAX mission is to make the interoperable. Just like WiFi did for No WiMAX compliant products today, foreseen during The first WiMAX products will be based on d. Intel is the most powerful player in WiMAX forum Architecture specification work initiated in a new sub- group

WIMAX © 2005 H. H’mimyLecture 11, Slide 4SMU EE 8315 Advanced Topics in Wireless Communications - Spring’05 WiMAX forum.. FDD as well as TDD Licensed as well as unlicensed spectrum –Licensed needed to guarantee wide area service No single global spectrum assigned, possibilites: –5.8 GHz –3.5 GHz –2.5 GHz, (IMT-2000 more likely in this band) –2.3 GHz

WIMAX © 2005 H. H’mimyLecture 11, Slide 5SMU EE 8315 Advanced Topics in Wireless Communications - Spring’05 38% of US households are interested in a Portable Broadband Service... 7% 9% 8% 37% 20% 13% 5% 0% 10% 20% 30% 40% 50% Definitely would not 23Neutral56Definitely would Interest in Portable Broadband Services (n = 3,370 U.S. Broadband Households) Source: Unlicensed Broadband Wireless: Solutions and Applications © 2004 Parks Associates 38%

WIMAX © 2005 H. H’mimyLecture 11, Slide 6SMU EE 8315 Advanced Topics in Wireless Communications - Spring’05 Broadband Technologies 3G Evolved802.16DSL/Fiber Fixed Triple Play (Video) IP Telephony Internet Fixed Nomadic IP Telephony Internet Full mobility Full roaming All over the world POMS IP Telephony Internet

WIMAX © 2005 H. H’mimyLecture 11, Slide 7SMU EE 8315 Advanced Topics in Wireless Communications - Spring’05 WiMAX Standards Roadmap 10 – 66 GHz LOS Sep Some Mobility 2005 ? e NOTE: IEEE specifies only layer 1 & 2 2 – 11 GHz NLOS Jan a WiMAX = interoperable subset of this (< 6 GHz) Similar to.16a Errata Jul d

WIMAX © 2005 H. H’mimyLecture 11, Slide 8SMU EE 8315 Advanced Topics in Wireless Communications - Spring’05

WIMAX © 2005 H. H’mimyLecture 11, Slide 9SMU EE 8315 Advanced Topics in Wireless Communications - Spring’05 DSL complement  DSL is not available, e.g. poor copper infrastructure  DSL OPEX too high, e.g. low population density  Central Office is too far away for DSL  CLEC bypassing incumbent DSL competition  If DSL is available, hard to beat for Broadband Wireless Access

WIMAX © 2005 H. H’mimyLecture 11, Slide 10SMU EE 8315 Advanced Topics in Wireless Communications - Spring’05 WiMAX segments, High level pros and cons Backhaul, Fixed, point to point – LOS –High Bitrate –Low Interference –Clear Signal – No multipath fading –Relatively Low Cost DSL, Fixed up to portable, Point to point, point to multipoint – NLOS –Relative high bitrate, but lower –One cell –Still relative cheap –Low to moderate interference-> Static radio environment WAN and Mobile environment –Significantly lower bitrate –High interference. More multipath fading and dopplershift effects

WIMAX © 2005 H. H’mimyLecture 11, Slide 11SMU EE 8315 Advanced Topics in Wireless Communications - Spring’05 IEEE Standard d/HiperMAN802.16e Completed December 2001June 2004 (802.16d)Estimate 2005 Spectrum GHz< 11 GHz< 6 GHz Channel Conditions Line of Sight OnlyNon Line of Sight Bit Rate 32 – 134 Mbps in 28MHz channel bandwidth Up to 75 Mbps in 20MHz channel bandwidth Up to 15 Mbps in 5MHz channel bandwidth Modulation QPSK, 16QAM and 64QAM OFDM 256 FFT QPSK, 16QAM, 64QAM Scalable OFDMA 128 to 2048 FFT Mobility Fixed Portable Channel Bandwidths 20, 25 and 28 MHz1.75 to 20 MHz WiMAX

WIMAX © 2005 H. H’mimyLecture 11, Slide 12SMU EE 8315 Advanced Topics in Wireless Communications - Spring’05 WIMAX Features FeatureBenefit 256 point FFT OFDM waveform Built in support for addressing multipath in outdoor LOS and NLOS environments Adaptive Modulation and variable error correction encoding per RF burst Ensures a robust RF link while maximizing the number of bits/second for each subscriber unit TDD and FDD duplexing support Address varying worldwide regulations where one or both may be allowed Flexible Channel sizes (such as 3.5 MHz, 5 MHz, 10 MHz, and so on) Provides the flexibility necessary to operate in many different frequency bands with varying channel requirements around the world Designed to support smart antenna systems Smart antennas are fast becoming more affordable, and as these costs come down their ability to suppress interference and increase system gain will become important to BWA deployments

WIMAX © 2005 H. H’mimyLecture 11, Slide 13SMU EE 8315 Advanced Topics in Wireless Communications - Spring’05 WiMAX Modulation and Coding The further the subscriber is from the base station, the greater the likelihood of a lower form of modulation and a higher amount of coding and thus a lower bit-rate

WIMAX © 2005 H. H’mimyLecture 11, Slide 14SMU EE 8315 Advanced Topics in Wireless Communications - Spring’05 Fit with Other Technologies Whether a will complement or clash with certain other technologies remains to be seen. For a while, at least, it will certainly be complementary to a, enabling Wi-Fi users to dramatically extend their distance from wired networks.

WIMAX © 2005 H. H’mimyLecture 11, Slide 15SMU EE 8315 Advanced Topics in Wireless Communications - Spring’05 Theoretical WiMAX Raw Bandwidth (Mbit/s)* Modulation / Code rate 1,75 MHz 3,5 MHz 7,0MHz 14,0 MHz 20,0 MHz QPSK 1/2QPSK 3/ QAM 3/416 QAM 1/ QAM 2/364 QAM 3/ *OFDM 256 FFT. Includes MAC and preamble overhead

WIMAX © 2005 H. H’mimyLecture 11, Slide 16SMU EE 8315 Advanced Topics in Wireless Communications - Spring’05 Theoretical Coverage (Km)* Type of Area Rural Suburban Urban N/A Rooftop Antenna Window/Fixed Antenna <8 Km Indoor/Portable Antenna *Approximate distances only, depends heavily on geographical area <4 Km <2 Km <4 Km <2 Km <1 Km <20 Km using NLOS** **<50 Km is the theoretical maximum for LOS. Assumption is a NLOS base station and a rooftop antenna for better reception and maximum uplink power

WIMAX © 2005 H. H’mimyLecture 11, Slide 17SMU EE 8315 Advanced Topics in Wireless Communications - Spring’05 Portability (Mobility) in e New network reference model –New BS-BS interface (IB) and BS-server interface (A) defined –Authentication and service authorization (ASA) servers provide authorization, authentication, billing, management, provisioning and other services. EAP is defined for SIM cards, and other means of Authentication.

WIMAX © 2005 H. H’mimyLecture 11, Slide 18SMU EE 8315 Advanced Topics in Wireless Communications - Spring’05 Enhancements for mobility in e – Layer 2 Handover (HO) process defined in MAC including –cell reselection –target BS scanning –network re-entry –HO decision and initiation and HO cancellation. MAC messages for each of the handover functions defined. Broadcast paging message defined. Neighbor topology advertisement messages defined. Option of using mobile IP provided. To be defined in May-05. WG active. Full QoS supported. All four GSM/WCDMA classes.

WIMAX © 2005 H. H’mimyLecture 11, Slide 19SMU EE 8315 Advanced Topics in Wireless Communications - Spring’05 Enhancements for mobility in e – Layer 1 Sleep mode, paging enabled. Fast time alignment (ranging) mechanism Flexible FFT sizes depending on channel bandwidth to ensure OFDM symbol duration is compatible with mobility requirements Soft handover, i.e., transmit/receive from multiple BS Fast channel feedback Fast BSS handover involving maintenance of sync to multiple BS’ while transmitting/receiving from anchor BS New MIMO, STC modes –MIMO soft-handoff based macro-diversity transmission –Space-time codes for 3 antenna configurations. Fixed version has 2 and 4 antenna modes.

WIMAX © 2005 H. H’mimyLecture 11, Slide 20SMU EE 8315 Advanced Topics in Wireless Communications - Spring’05 some differences MAC –802.11: Contention-based MAC (CSMA/CA), basically wireless Ethernet. –802.16: Dynamic TDMA-based MAC with on-demand bandwidth allocation. OFDM –802.11a: 64 FTTs –802.16d: 256 FFTs Spectrum –802.11: limited channels in Un-license spectrum –802.16: multiple channels in licensed & Un-license spectrum

WIMAX © 2005 H. H’mimyLecture 11, Slide 21SMU EE 8315 Advanced Topics in Wireless Communications - Spring’05 Comparison and < 300 feet Optimized for indoor short range 2.7 bps/Hz peak. <= 54Mbps in 20MHz 1-10 CPE CSMA/CA No QOS Technology Range Coverage Data rate Scalability QOS < 30 Mile ( typical 3~4) Outdoor LOS & NLOS 5bps/Hz peak, <100Mbps in 20 MHz 1- hundreds CPE TDMA On demand BW  voice Video, data

WIMAX © 2005 H. H’mimyLecture 11, Slide 22SMU EE 8315 Advanced Topics in Wireless Communications - Spring’05 WiMAX Wireless Broadband Laptop centric Fixed  Portability Line-of-Sight & Non Line-of-Sight IEEE Layer 1 & 2 standard Data optimized Optimized for Fixed High data rate Evolution towards mobility Drivers: Data optimized network (simple) DSL complement Broadband Wireless systems 3G Evolved Mobile Broadband Phone & laptop Full mobility Non line-of-sight 3GPP and 3GPP2 standard Voice/data optimized Optimized for Mobility Evolution towards Higher Data Drivers: Mobile Broadband for incremental investment National & global roaming networks

WIMAX © 2005 H. H’mimyLecture 11, Slide 23SMU EE 8315 Advanced Topics in Wireless Communications - Spring’05 1xEV-DV 1xEV-DO HSDPA EDGE GSM/GPRS WCDMA CDMA2000 1x Flarion IEEE d ChannelBandwidth 200KHz 5Mhz 1.25 MHz Peakbit-rateDL 160 kbps PeakBit-rateUL FDD/TDD -20 MHz 480 kbps 2 Mbps 14.4 Mbps 640 kbps 3.1 Mbps - 75 Mbps 3.2 Mbps 160 kbps 480 kbps 2 Mbps 7.68 Mbps 450 kbps 1.8 Mbps - 75 Mbps 900 kbps FDD FDD/TDD FDD FDD/TDD FDD Standardscompliant 3GPP _ Peak Bit Rates Comparison 3GPP 3GPP2 IEEE

WIMAX © 2005 H. H’mimyLecture 11, Slide 24SMU EE 8315 Advanced Topics in Wireless Communications - Spring’05 User data rates WCDMACDMA2000Flash-OFDMWCDMA Release 991xEV-DO(Proprietary)Evolved (HSDPA) Peak data rate according to Specification (Mbps) Average data rate in the Field (Mbps)

WIMAX © 2005 H. H’mimyLecture 11, Slide 25SMU EE 8315 Advanced Topics in Wireless Communications - Spring’05 Propagation difference between 1900MHz and other frequencies ( H-O Model) 2100MHz ( Delta = 1.1dB) 2400MHz ( Delta = 2.6dB) 3500MHz ( Delta = 7dB) 850 MHz ( Delta = -12 dB)

WIMAX © 2005 H. H’mimyLecture 11, Slide 26SMU EE 8315 Advanced Topics in Wireless Communications - Spring’05 WiMax IEEE802.16a, e Understanding WiMax – – – OFDM – Adaptive modulation –