1. doc.: IEEE 802.11-04/888r3 Submission November 2004 Syed Aon Mujtaba, Agere Systems, et. al.Slide 1 TGn Sync Complete Proposal Aon Mujtaba, Agere Systems Inc., (mujtaba@agere.com)mujtaba@agere.com Adrian P Stephens, Intel Corporation, (adrian.p.stephens@intel.com)adrian.p.stephens@intel.com Alek Purkovic, Nortel Networks (apurkovi@nortelnetworks.com)apurkovi@nortelnetworks.com Andrew Myles, Cisco Systems (amyles@cisco.com)amyles@cisco.com Brian Johnson, Nortel Networks Corporation, (brjohnso@nortelnetworks.com)brjohnso@nortelnetworks.com Chiu Ngo, Samsung Electronics Co. Ltd., (chiu.ngo@samsung.com)chiu.ngo@samsung.com Daisuke Takeda, Toshiba Corporation, (daisuke.takeda@toshiba.co.jp)(daisuke.takeda@toshiba.co.jp Darren McNamara, Toshiba Corporation, (Darren.McNamara@toshiba-trel.com)Darren.McNamara@toshiba-trel.com Dongjun (DJ) Lee, Samsung Electronics Co. Ltd., (djthekid.lee@samsung.com)djthekid.lee@samsung.com David Bagby, Calypso Consulting, (david.bagby@ieee.org)david.bagby@ieee.org Eldad Perahia, Cisco Systems, (eperahia@cisco.com)eperahia@cisco.com Huanchun Ye, Atheros Communications Inc., (hcye@atheros.com)hcye@atheros.com Hui-Ling Lou, Marvell Semiconductor Inc., (hlou@marvell.com)hlou@marvell.com Isaac Lim Wei Lih, Panasonic (wllim@psl.com.sg)wllim@psl.com.sg James Chen, Marvell Semiconductor Inc., (jamesc@marvell.com)jamesc@marvell.com James Mike Wilson, Intel Corporation, (james.mike.wilson@intel.com)james.mike.wilson@intel.com Jan Boer, Agere Systems Inc., (janboer@agere.com)janboer@agere.com Jari Jokela, Nokia, (jari.jokela@nokia.com)jari.jokela@nokia.com

2. doc.: IEEE 802.11-04/888r3 Submission November 2004 Syed Aon Mujtaba, Agere Systems, et. al.Slide 2 Authors (continued) Jeff Gilbert, Atheros Communications Inc., (gilbertj@atheros.com)gilbertj@atheros.com Job Oostveen, Royal Philips Electronics, (job.oostveen@philips.com)job.oostveen@philips.com Joe Pitarresi, Intel Corporation, (joe.pitarresi@intel.com)joe.pitarresi@intel.com Jörg Habetha, Royal Philips Electronics, (joerg.habetha@philips.com)joerg.habetha@philips.com John Sadowsky, Intel Corporation, (john.sadowsky@intel.com)john.sadowsky@intel.com Jon Rosdahl, Samsung Electronics Co. Ltd., (jon.rosdahl@partner.samsung.com)jon.rosdahl@partner.samsung.com Kiyotaka Kobayashi, Panasonic (kobayashi.kiyotaka@jp.panasonic.com)kobayashi.kiyotaka@jp.panasonic.com Luke Qian, Cisco Systems, (lchia@cisco.com)lchia@cisco.com Mary Cramer, Agere Systems (mecramer@agere.com)mecramer@agere.com Masahiro Takagi, Toshiba Corporation, (masahiro3.takagi@toshiba.co.jp)masahiro3.takagi@toshiba.co.jp Monisha Ghosh, Royal Philips Electronics, (monisha.ghosh@philips.com)monisha.ghosh@philips.com Nico van Waes, Nokia, (nico.vanwaes@nokia.com)nico.vanwaes@nokia.com Osama Aboul-Magd, Nortel Networks Corporation, (osama@nortelnetworks.com)osama@nortelnetworks.com Paul Feinberg, Sony Electronics Inc., (paul.feinberg@am.sony.com)paul.feinberg@am.sony.com Pen Li, Royal Philips Electronics (pen.li@philips.com)pen.li@philips.com Peter Loc, Marvell Semiconductor Inc., (ploc@marvell.com)ploc@marvell.com Pieter-Paul Giesberts, Agere Systems Inc., (pgiesberts@agere.com)pgiesberts@agere.com Richard van Leeuwen, Agere Systems Inc., (rleeuwen@agere.com)rleeuwen@agere.com Ronald Rietman, Royal Philips Electronics, (ronald.rietman@philips.com)ronald.rietman@philips.com Seigo Nakao, SANYO Electric Co. Ltd., (snakao@gf.hm.rd.sanyo.co.jp)snakao@gf.hm.rd.sanyo.co.jp Sheung Li, Atheros Communications Inc., (sheung@atheros.com)sheung@atheros.com

3. doc.: IEEE 802.11-04/888r3 Submission November 2004 Syed Aon Mujtaba, Agere Systems, et. al.Slide 3 Authors (continued) Stephen Shellhammer, Intel, (stephen.j.shellhammer@intel.com)stephen.j.shellhammer@intel.com Taekon Kim, Samsung Electronics Co. Ltd., (taekon.kim@samsung.com)taekon.kim@samsung.com Takashi Fukagawa, Panasonic, (fukagawa.takashi@jp.panasonic.com)fukagawa.takashi@jp.panasonic.com Takushi Kunihiro, Sony Corporation, (kuni@wcs.sony.co.jp)kuni@wcs.sony.co.jp Teik-Kheong (TK) Tan, Royal Philips Electronics, (tktan@philips.com)tktan@philips.com Tomoko Adachi, Toshiba Corporation, (tomo.adachi@toshiba.co.jp)tomo.adachi@toshiba.co.jp Tomoya Yamaura, Sony Corporation, (yamaura@wcs.sony.co.jp)yamaura@wcs.sony.co.jp Tsuguhide Aoki, Toshiba Corporation, (tsuguhide.aoki@toshiba.co.jp)tsuguhide.aoki@toshiba.co.jp Victor Stolpman, Nokia, (victor.stolpman@nokia.com)victor.stolpman@nokia.com Won-Joon Choi, Atheros Communications Inc., (wjchoi@atheros.com)wjchoi@atheros.com Xiaowen Wang, Agere Systems Inc., (xiaowenw@agere.com)xiaowenw@agere.com Yasuhiko Tanabe, Toshiba Corporation, (yasuhiko.tanabe@toshiba.co.jp)yasuhiko.tanabe@toshiba.co.jp Yasuhiro Tanaka, SANYO Electric Co. Ltd., (y_tanaka@gf.hm.rd.sanyo.co.jp)y_tanaka@gf.hm.rd.sanyo.co.jp Yoshiharu Doi, SANYO Electric Co. Ltd., (doi@gf.hm.rd.sanyo.co.jp)doi@gf.hm.rd.sanyo.co.jp Youngsoo Kim, Samsung Electronics Co. Ltd., (KimYoungsoo@samsung.com)KimYoungsoo@samsung.com Yuichi Morioka, Sony Corporation, (morioka@wcs.sony.co.jp)morioka@wcs.sony.co.jp

4. doc.: IEEE 802.11-04/888r3 Submission November 2004 Syed Aon Mujtaba, Agere Systems, et. al.Slide 4 TGn Sync Mission Statement  Develop a scalable architecture to support present and emerging applications  Foster a broad industry representation from vendors and OEMs across market segments

5. doc.: IEEE 802.11-04/888r3 Submission November 2004 Syed Aon Mujtaba, Agere Systems, et. al.Slide 5 Scalable Architecture across several dimensions Perf. over time Market segments Regulatory Domains 10MHz (.11j/p) 20MHz 40MHz 140Mbps 315Mbps630Mbps PC Enterprise Consumer Electronics Public Access Handset

6. doc.: IEEE 802.11-04/888r3 Submission November 2004 Syed Aon Mujtaba, Agere Systems, et. al.Slide 6 … And a well-defined Core Perf. over time Market segments Regulatory Domains Mandatory Features: - Two antennas - 20MHz - 140 Mbps

7. doc.: IEEE 802.11-04/888r3 Submission November 2004 Syed Aon Mujtaba, Agere Systems, et. al.Slide 7 Broad Industry Representation  OEMs ■ Cisco ■ Nokia ■ Nortel ■ Panasonic ■ Sony ■ Sanyo ■ Samsung ■ Toshiba  Semi Vendors ■ Agere ■ Atheros ■ Intel ■ Marvell ■ Philips PC Enterprise Consumer Electronics Asia Pacific / Europe / North America Semiconductor Handset Public Access

8. doc.: IEEE 802.11-04/888r3 Submission November 2004 Syed Aon Mujtaba, Agere Systems, et. al.Slide 8 PHY Summary of TGnSync Proposal  Mandatory Features: ■ 2 Spatial Streams ■ 20MHz and 40MHz* channelization ■ 1/2, 2/3, 3/4, and 7/8 channel coding rates ■ 400ns & 800ns Guard Interval ■ Full & seamless interoperability with a/b/g  Optional Features: ■ Transmit Beamforming ■ Low Density Parity Check (LDPC) Coding ■ 3 or 4 spatial streams *Not required in regulatory domains where prohibited. 140Mbps in 20MHz 243Mbps in 40MHz

9. doc.: IEEE 802.11-04/888r3 Submission November 2004 Syed Aon Mujtaba, Agere Systems, et. al.Slide 9 MAC Summary of TGn Sync Proposal  Mandatory Features: ■ MAC Level Frame Aggregation ■ Link Adaptation ■ Legacy Compatible Protection ■ QoS Support (802.11e) ■ Multi-Destination Aggregation ■ MAC Header Compression ■ Block ACK Compression ■ 20/40 MHz Channel management **  Optional Features: ■ Bi-directional data flow ■ Power management for MIMO receivers Optional at Transmitter Mandatory at Receiver ** Depends on local regulation

10. doc.: IEEE 802.11-04/888r3 Submission November 2004 Syed Aon Mujtaba, Agere Systems, et. al.Slide 10 PHY

11. doc.: IEEE 802.11-04/888r3 Submission November 2004 Syed Aon Mujtaba, Agere Systems, et. al.Slide 11 PHY Architectural Features  Mandatory throughput enhancement: ■ Spatial division multiplexing (SDM) of 2 Spatial Streams ■ Bandwidth expansion  interoperable 20MHz and 40MHz* ■ Increased channel coding rate (i.e. 7/8) ■ Shortened guard interval (i.e. 400ns)  Optional robustness & throughput enhancement: ■ Transmit beamforming ■ Advanced coding (LDPC) ■ SDM with 3 or 4 spatial streams * Not required in regulatory domains where prohibited Max Mandatory rate in 20MHz = 140 Mbps Max Mandatory rate in 40MHz = 243 Mbps (with 2x2 architecture using 2 spatial streams) with the option to scale to 630Mbps

12. doc.: IEEE 802.11-04/888r3 Submission November 2004 Syed Aon Mujtaba, Agere Systems, et. al.Slide 12 Scalable PHY Architecture Open Loop SDM Rate Feedback 2 Spatial Streams 20 MHz Regulatory Constraints 40 MHz Low Cost & Robust  140 Mbps  243 Mbps Robustness Enhancement Closed Loop TX BF 4 Spatial Streams Throughput Enhancement Conv. Coding LDPC Robustness Enhancement  630 Mbps Mandatory Optional

13. doc.: IEEE 802.11-04/888r3 Submission November 2004 Syed Aon Mujtaba, Agere Systems, et. al.Slide 13 40MHz Mandatory Where Possible  Situation ■ 40MHz solution offers high throughput and robustness with the fewest antennas  Complication ■ Some major world markets are currently restricted to 20MHz channel bandwidth ■ Market confusion & reduced network efficiency if HT devices are both 20-HT-only and 20/40-HT  Industry leadership opportunity ■ Make 40MHz HT product mandatory where possible, with 20MHz interoperability ■ All 20MHz-only product fully compatible with 20/40MHz product

14. doc.: IEEE 802.11-04/888r3 Submission November 2004 Syed Aon Mujtaba, Agere Systems, et. al.Slide 14 Mapping Spatial Streams to Multiple Antennas  Number of spatial streams = Number of TX antennas ■ 1 spatial stream mapped to 1 antenna ■ Spatial division multiplexing ■ Equal rates on all spatial streams  Number of spatial streams ≤ Number of TX antennas ■ Each spatial stream mapped to all transmit antennas ■ Optional orthogonal spatial spreading Exploits all transmit antennas No channel state info at TX required ■ Optional transmit beamforming Focusing the energy in a desired direction Requires channel state info at TX Supports unequal rates on different spatial streams ■ With per spatial stream training, no change needed at the RX

15. doc.: IEEE 802.11-04/888r3 Submission November 2004 Syed Aon Mujtaba, Agere Systems, et. al.Slide 15 TX Arch: Spatial Division Multiplexing e.g. 2 Spatial streams with 2 TX antennas (mandatory) Channel Encoder Puncturer Frequency Interleaver Constellation Mapper iFFT Modulator insert GI window symbols Pilots Preamble Scrambled MPDU Frequency Interleaver Constellation Mapper iFFT Modulator insert GI window symbols Pilots Preamble Spatial parser

16. doc.: IEEE 802.11-04/888r3 Submission November 2004 Syed Aon Mujtaba, Agere Systems, et. al.Slide 16 Tone Design for 20 and 40 MHz -58-6+6+58-64+63 -53 -25-11+11+25+53 -2+2 -32 +32 Legacy 20 MHz in Lower Sub-Channel Legacy 20 MHz in Upper Sub-Channel -26+26+1-21-7+7+21 20 MHz: Identical to 802.11a 64 point FFT 48 data tones 4 pilot tones 40 MHz: 128 point FFT 108 data tones 6 pilot tones Tone Fill in the Guard Band

17. doc.: IEEE 802.11-04/888r3 Submission November 2004 Syed Aon Mujtaba, Agere Systems, et. al.Slide 17 Motivation for 40MHz Channelization 0 20 40 60 80 100 120 140 160 180 200 220 240 260 05101520253035 SNR (dB) Over the Air Throughput (Mbps) 2x2-40 MHz 4x4-20 MHz 2x2-20 MHz w/ short GI 2x3-20 MHz w/ short GI 2x2 – 40 MHz Only 2 RF chains => Cost effective & low power Lower SNR at same throughput => Enhanced robustness Basic MIMO MCS set No impairments 1000 byte packets TGn channel model B Sweet spot for 100 Mbps top-of-MAC

18. doc.: IEEE 802.11-04/888r3 Submission November 2004 Syed Aon Mujtaba, Agere Systems, et. al.Slide 18 ‡ Duplicate format, BPSK R = ½ provides 6 Mbps for 40 MHz channels Scalable Basic MCS Set ModulationCode Rate Data Rates 20 MHz (Mbps) (1,2,3,4 spatial streams) Data Rates 40 MHz (Mbps) (1,2,3,4 spatial streams) BPSK1/26, 12, 18, 246 ‡, 13.5, 27, 45.5, 54 QPSK1/212, 24, 36, 4827, 54, 81, 108 QPSK3/418, 35, 54, 7240.5, 81, 121.5, 162 16 QAM1/224, 48, 72, 9654, 108, 162, 216 16 QAM3/436, 72, 108, 14481, 162, 243, 324 64 QAM2/348, 96, 144, 192108, 216, 324, 432 64 QAM3/454, 108, 162, 216121.5, 243, 364.5, 486 64 QAM7/863, 126, 189, 252141.7, 283.5, 425.2, 567 64 QAM7/8 with ½ GI70, 140, 210, 280157.5, 315, 472.5, 630 Mandatory MCS Optional MCS

19. doc.: IEEE 802.11-04/888r3 Submission November 2004 Syed Aon Mujtaba, Agere Systems, et. al.Slide 19 HT-PPDU Format in 20MHz 20MHz ANT_1 Legend L-Legacy HT-High Throughput STFShort Training Field LTFLong Training Field SIGSignal Field Legacy Compatible Can be decoded by any legacy 802.11a or g compliant device for interoperability L-STFL-LTFL-SIGHT-SIGHT-DATA L-STFL-LTFL-SIGHT-SIGHT-DATA Legacy Compatible PreambleHT-specific Preamble HT STF HT LTF-1 HT LTF-2 20MHz ANT_2

20. doc.: IEEE 802.11-04/888r3 Submission November 2004 Syed Aon Mujtaba, Agere Systems, et. al.Slide 20 HT-PPDU Format in 40MHz ANT_1 ANT_2 40MHz Legacy Compatible PreambleHT-specific Preamble HT STF HT LTF-1 HT LTF-2 L-STFL-LTFL-SIGHT-SIG HT-DATA Duplicate L-STF Duplicate L-LTF Dup. L-SIG Duplicate HT-SIG L-STFL-LTFL-SIGHT-SIG HT-DATA Duplicate L-STF Duplicate L-LTF Dup. L-SIG Duplicate HT-SIG

21. doc.: IEEE 802.11-04/888r3 Submission November 2004 Syed Aon Mujtaba, Agere Systems, et. al.Slide 21 Spoofing  Spoofing is the use of the legacy RATE and LENGTH fields to keep the legacy STA off the air for a desired period of time  The duration indicated in the L-SIG can exceed the actual duration in the HT-SIG  MAC uses this as a protection mechanism  For a HT-PPDU, L-SIG RATE is hard-coded at 6 Mbps ■ max MSDU length = 2304 Bytes  spoofing duration up to ~3 msec

22. doc.: IEEE 802.11-04/888r3 Submission November 2004 Syed Aon Mujtaba, Agere Systems, et. al.Slide 22 HT PPDU Detection  Auto-detection scheme on HT-SIG ■ Q-BPSK modulation (BPSK w/ 90-deg rotation) ■ Invert the polarity of the pilot tones ■ Combined methods provide speed and reliability  L-SIG reserved bit is not used ■ Legacy devices are using the “reserved bit” in undefined ways L-STFL-LTFL-SIGHT-SIG L-STFL-LTFL-SIG or Legacy DATA Legacy Compatible Preamble

23. doc.: IEEE 802.11-04/888r3 Submission November 2004 Syed Aon Mujtaba, Agere Systems, et. al.Slide 23 HT-SIG Contents 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 MCS (6 bits) HTLENGTH (18 bits) 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 SIGNAL TAIL (6 bits) 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 MCS (6 bits) HTLENGTH (18 bits) ADV CODING (1 bit) NUMBER HT-LTF (2 bits) SCRAMBLER INIT (2 bits) CRC (8 bits) SIGNAL TAIL (6 bits) HT-SIG1 Transmit Order SOUNDING PACKET (1 bit) SHORT GI (1 bit) AGGRAGATE (1 bit)20/40 BW (1 bit) RESERVED (1 bit) HT-SIG2

24. doc.: IEEE 802.11-04/888r3 Submission November 2004 Syed Aon Mujtaba, Agere Systems, et. al.Slide 24 MIMO AGC  For MIMO, accurate AGC requires power estimates from each TX antenna to each RX antenna  If L-STF is used for MIMO AGC, require orthogonalization of L-STF across multiple TX antennas  Perfect orthogonality is achieved with tone interleaving ■ However, tone interleaving is incompatible with legacy receivers using cross correlation on the L-STF  Cyclic delay may be used to separate transmission paths, but the delay has to be limited to preserve the cross correlation property of the L-STF ■ However, limited cyclic delay results in AGC inaccuracy, as shown on the next slide L-STFL-LTFL-SIGHT-SIGHT-DATA single spatial stream multiple spatial streams AGC measured AGC locked

25. doc.: IEEE 802.11-04/888r3 Submission November 2004 Syed Aon Mujtaba, Agere Systems, et. al.Slide 25 Power Fluctuation with Cyclic Delay on the L-STF -7-6-5-4-3-20123 0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1 x = Power fluctuation of AGC setting w.r.t. data power (dB) STF = Tone Interleaved STF = Cyclic Delay CDF(x) Power fluctuation with tone interleaving is within 1dB of the data power Data power Introduce a dedicated STF for MIMO that is tone interleaved Reduces 1 bit in the ADC  cost & power savings 2x2, TGn Channel D SNR = 30dB

26. doc.: IEEE 802.11-04/888r3 Submission November 2004 Syed Aon Mujtaba, Agere Systems, et. al.Slide 26 Power Fluctuation of HT-LTF w.r.t. Data -10-8-6-4-2024 0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1 x = Power fluctuation of HT-LTF w.r.t. data (dB) CDF(x) HT-LTF = Tone Interleaved HT-LTF = Walsh + Cyclic Delay 2x2, TGn Channel D SNR = 30dB Data power Large deviation of HT-LTF power wrt data power will result in higher channel estimation error HT-LTF should be tone interleaved

27. doc.: IEEE 802.11-04/888r3 Submission November 2004 Syed Aon Mujtaba, Agere Systems, et. al.Slide 27 Tone Interleaved HT Training Fields  HT-STF ■ 2 nd AGC measurement is used to fine-tune MIMO reception  HT-LTF ■ Used for MIMO channel estimation ■ Additional frequency or time alignment

28. doc.: IEEE 802.11-04/888r3 Submission November 2004 Syed Aon Mujtaba, Agere Systems, et. al.Slide 28 Spatial Stream Tone Interleaving Color indicates spatial stream Each HT-LTF has equal representation from all spatial streams Eliminates avg. power fluctuation across LTFs HT-LTS symbols are designed to minimize PAPR Distinct symbol designs for different number of spatial streams

29. doc.: IEEE 802.11-04/888r3 Submission November 2004 Syed Aon Mujtaba, Agere Systems, et. al.Slide 29 Summary of HT-LTF  Robust design ■ Tone interleaving reduces power fluctuation ■ 2 symbols per field 3dB of channel estimation gain with baseline per-tone estimation Enables additional frequency offset estimation  Per spatial stream training ■ HT-LTF and HT-Data undergo same spatial transformation ■ Number of HT-LTFs = Number of spatial streams

30. doc.: IEEE 802.11-04/888r3 Submission November 2004 Syed Aon Mujtaba, Agere Systems, et. al.Slide 30 20/40 MHz BSS Operation  A 20/40 MHz BSS supports interoperability among any combination of: ■ 20/40 MHz HT clients ■ 20 MHz HT client ■ 20 MHz legacy client  Not required in regulatory domains where prohibited

31. doc.: IEEE 802.11-04/888r3 Submission November 2004 Syed Aon Mujtaba, Agere Systems, et. al.Slide 31 20/40 MHz Interoperability  40 MHz PPDU into a 40 MHz receiver ■ Get 3dB processing gain – duplicate format allows combining the legacy compatible preamble and the HT-SIG in an MRC fashion  20 MHz PPDU into a 40 MHz receiver ■ The active 20 MHz sub-channel is detected using energy measurement of the two sub-channels ■ Inactive tones at the FFT output (i.e. 64 out of 128) are not used  40 MHz PPDU into a 20 MHz receiver ■ One 20 MHz sub-channel is sufficient to decode the L-SIG and the HT-SIG  See MAC slides for additional information on 20/40 inter-op

32. doc.: IEEE 802.11-04/888r3 Submission November 2004 Syed Aon Mujtaba, Agere Systems, et. al.Slide 32 TX Arch: Basic TX Beamforming or Spatial Spreading e.g. 2 Spatial Streams with 3 TX Antennas (optional) Channel Encoder Puncturer Frequency Interleaver Constellation Mapper Pilots HT LTF Scrambled MPDU Frequency Interleaver Constellation Mapper Pilots Spatial Steering (TX Beamforming), or Orthogonal Spatial Spreading with Cyclical Delay Per Spatial Stream Processing: HT-LTF & HT-Data undergo same spatial transformation iFFT Mod. insert GI window iFFT Mod. insert GI iFFT Mod. insert GI window Spatial Parser HT LTF

33. doc.: IEEE 802.11-04/888r3 Submission November 2004 Syed Aon Mujtaba, Agere Systems, et. al.Slide 33 SNR Gain with TX Beamforming 1000 byte packets No impairment 20MHz, channel D 4 TX-antenna AP 2 RX-antenna client ~10 dB gain of 4x2-ABF over 2x2-SDM => cost effective client

34. doc.: IEEE 802.11-04/888r3 Submission November 2004 Syed Aon Mujtaba, Agere Systems, et. al.Slide 34 Optional Advanced Coding  Low Density Parity Check (LDPC) ■ Capacity approaching FEC ■ Iterative decoding  superior performance  Strong performance in AWGN and fading channels ■ Typically 2-4 dB improvement over convolutional codes, depending on channel conditions  Code structure enables low complexity architectures ■ Layered belief propagation reduces memory requirements and improves convergence performance

35. doc.: IEEE 802.11-04/888r3 Submission November 2004 Syed Aon Mujtaba, Agere Systems, et. al.Slide 35 LDPC Performance Comparison 3.5 dB of coding gain

36. doc.: IEEE 802.11-04/888r3 Submission November 2004 Syed Aon Mujtaba, Agere Systems, et. al.Slide 36 PHY Summary  Mandatory Rate of 140Mbps in 20MHz: ■ 2 Spatial Streams ■ 7/8 th rate coding ■ 400ns Guard Interval  Low Cost & Robust Throughput Enhancement: ■ Scalable to 243 Mbps in 40MHz  Optional Robustness/Throughput Enhancements: ■ LDPC Coding ■ Transmit Beamforming ■ Scalable to 630Mbps with 4 spatial streams in 40MHz

37. doc.: IEEE 802.11-04/888r3 Submission November 2004 Syed Aon Mujtaba, Agere Systems, et. al.Slide 37 MAC

38. doc.: IEEE 802.11-04/888r3 Submission November 2004 Syed Aon Mujtaba, Agere Systems, et. al.Slide 38 MAC Challenges in HT Environment  HT requires an improvement in MAC Efficiency  HT requires effective Rate Adaptation  HT requires Legacy Protection

39. doc.: IEEE 802.11-04/888r3 Submission November 2004 Syed Aon Mujtaba, Agere Systems, et. al.Slide 39 HT MAC Features  Aggregation Structure  Header Compression  Aggregation Exchanges ■ Protocol for link adaptation ■ Protocol for reverse direction data ■ Single and multiple responder  Protection Mechanisms  Coexistence & Channel Management  MIMO Power Management  Block Ack Enhancements

40. doc.: IEEE 802.11-04/888r3 Submission November 2004 Syed Aon Mujtaba, Agere Systems, et. al.Slide 40 Scalable MAC Architecture BASELINE MAC Robust Aggregation QoS Support (802.11e) ADDITIONAL EFFICIENCY Header Compression Multi-Receiver Aggregation Bi-Directional Data Flow BA Enhancements LEGACY INTEROP. Long NAV Pairwise Spoofing Single-Ended Spoofing CHANNEL MANAGEMENT 20/40 MHz Modes Robust & Scalable MAC Architecture

41. doc.: IEEE 802.11-04/888r3 Submission November 2004 Syed Aon Mujtaba, Agere Systems, et. al.Slide 41 Aggregation Structure  Robust Structure  Aggregation is a purely-MAC function ■ PHY has no knowledge of MPDU boundaries ■ Simplest MAC-PHY interface  Control and data MPDUs can be aggregated

42. doc.: IEEE 802.11-04/888r3 Submission November 2004 Syed Aon Mujtaba, Agere Systems, et. al.Slide 42 MAC Header Compression  MHDR MPDU carries repeated Header fields  CHDATA MPDU refers to previous MHDR MPDU ■ HID field ties the two together ■ Context only within current aggregate

43. doc.: IEEE 802.11-04/888r3 Submission November 2004 Syed Aon Mujtaba, Agere Systems, et. al.Slide 43 Aggregate Exchange Sequences  Aggregate exchange sequences include single frames or groups of frames that are exchanged “at the same time” ■ Allows effective use of Aggregate Feature ■ Allows control and data to be sent in the same PPDU  An initiator sends a PPDU and a responder may transmit a response PPDU ■ Either PPDU can be an aggregate (“Initiator” / “responder” are new terms relating to roles in aggregate exchange protocol)

44. doc.: IEEE 802.11-04/888r3 Submission November 2004 Syed Aon Mujtaba, Agere Systems, et. al.Slide 44 Basic Aggregate Exchange

45. doc.: IEEE 802.11-04/888r3 Submission November 2004 Syed Aon Mujtaba, Agere Systems, et. al.Slide 45 Reverse Direction Data Flow  Gives an opportunity for a responder to transmit data to an initiator during the initiator’s TXOP  Aggregates data with response control MPDUs  Reduces Contention  Effective in increasing TCP/IP performance

46. doc.: IEEE 802.11-04/888r3 Submission November 2004 Syed Aon Mujtaba, Agere Systems, et. al.Slide 46 Reverse Direction Protocol

47. doc.: IEEE 802.11-04/888r3 Submission November 2004 Syed Aon Mujtaba, Agere Systems, et. al.Slide 47 Link Adaptation Protocol  Support for PHY closed-loop modes with on-the-air signalling  Request for training and feedback are carried in control frames  Rate feedback supported  Transmit beamforming training supported ■ sounding packet ■ calibration exchange  Timing of response is not constrained permitting a wide range of implementation options

48. doc.: IEEE 802.11-04/888r3 Submission November 2004 Syed Aon Mujtaba, Agere Systems, et. al.Slide 48 Link Adaptation Protocol

49. doc.: IEEE 802.11-04/888r3 Submission November 2004 Syed Aon Mujtaba, Agere Systems, et. al.Slide 49 Multiple Receiver Aggregation  Aggregates can contain MPDUs addressed for multiple receiver addresses (MRA)  MRA may be followed by multiple responses from the multiple receivers  MRA is effective in improving throughput in applications where frames are buffered to many receiver addresses

50. doc.: IEEE 802.11-04/888r3 Submission November 2004 Syed Aon Mujtaba, Agere Systems, et. al.Slide 50 Periodic Multi-Receiver Aggregation

51. doc.: IEEE 802.11-04/888r3 Submission November 2004 Syed Aon Mujtaba, Agere Systems, et. al.Slide 51 Multiple Responses  MRA contains multiple IAC for ■ One per response ■ At most one per receiver  IAC specifies response offset and duration

52. doc.: IEEE 802.11-04/888r3 Submission November 2004 Syed Aon Mujtaba, Agere Systems, et. al.Slide 52 Protection Mechanisms  LongNAV ■ An entire sequence is protected by NAV set using MPDU duration field or during contention-free period ■ CF-end packet at end of EDCA TXOP sequence may be used to return unused time by resetting NAV  Pairwise Spoofing ■ Protection of pairs of PPDUs sent between an initiator and a single responder ■ Uses Legacy PLCP header duration spoofing  Single-ended Spoofing ■ Protection of aggregate and any responses using legacy PLCP spoofing at the initiator only ■ Can be used to protect multiple responses

53. doc.: IEEE 802.11-04/888r3 Submission November 2004 Syed Aon Mujtaba, Agere Systems, et. al.Slide 53 LongNAV protection  Provides protection of a sequence of multiple PPDUs  Provides a solution for.11b  Comes “for free” with polled TXOP  Gives maximum freedom in use of TXOP by initiator

54. doc.: IEEE 802.11-04/888r3 Submission November 2004 Syed Aon Mujtaba, Agere Systems, et. al.Slide 54 Pairwise Spoofing Protection  Protects pairs of PPDUs (current and following)  Very low overhead, suitable for short exchanges, relies on robust PHY signaling  Places Legacy devices into receiving mode for spoofed duration  Spoofing is interpreted by HT devices as a NAV setting

55. doc.: IEEE 802.11-04/888r3 Submission November 2004 Syed Aon Mujtaba, Agere Systems, et. al.Slide 55 Single-Ended Spoofing Protection  Protects MRA and all responses  Very low overhead, suitable for short exchanges  Places legacy devices into receiving mode for spoofed duration  Same level of protection as initiator CTS-to-Self ■ Assuming CTS is sent at the lowest rate

56. doc.: IEEE 802.11-04/888r3 Submission November 2004 Syed Aon Mujtaba, Agere Systems, et. al.Slide 56 Following Packet Descriptor (FPD) Protocol

57. doc.: IEEE 802.11-04/888r3 Submission November 2004 Syed Aon Mujtaba, Agere Systems, et. al.Slide 57 Operating Mode Selection  BSS operating mode controls the use of protection mechanisms and 20/40 width switching by HT STA ■ Supports mixed BSS of legacy + HT devices  HT AP-managed modes ■ If only the control channel is overlapped, managed mixed mode provides a low overhead alternative to mixed mode ■ If both channels are overlapped, 20 MHz base mode allows an HT AP to dynamically switch channel width for 40 MHz- capable HT STA

58. doc.: IEEE 802.11-04/888r3 Submission November 2004 Syed Aon Mujtaba, Agere Systems, et. al.Slide 58 20 MHz-base Managed Mixed Mode ch_a (control) CTS self /Bcn CF- End t ch_b (extension) Bcn/ ICB CF- End CF- End t RCB NAV ch_a NAV ch_b NAV ch_a+ch_b 20MHz 40MHz 20MHz Carrier Sense (CS) CS

59. doc.: IEEE 802.11-04/888r3 Submission November 2004 Syed Aon Mujtaba, Agere Systems, et. al.Slide 59 Channel Selection  Support 20/40 MHz and 20 MHz operating modes of whole BSS  In 20/40 MHz mode, all legacy PPDUs are 20 MHz, all HT PPDUs exchanged between HT STA are either 40 MHz or 20 MHz depending on operating mode and STA capability  Channel selection constraints ■ Partial overlap between HT systems is not allowed ■ Legacy STAs are only allowed in the control sub-channel except in 20 MHz-base managed mixed mode  An HT AP responds to changes in environment to maintain channel selection constraints

60. doc.: IEEE 802.11-04/888r3 Submission November 2004 Syed Aon Mujtaba, Agere Systems, et. al.Slide 60 MIMO Power Management  Timed Receive Mode Switching (TRMS) allows a STA to operate with only 1 of its receive chains enabled most of the time ■ Switch to fully enabled when the STA transmits a frame ■ Hold-on timer keeps the STA fully enabled for a known period of time  Good for bursty traffic ■ reduced latency compared to other methods of power saving

61. doc.: IEEE 802.11-04/888r3 Submission November 2004 Syed Aon Mujtaba, Agere Systems, et. al.Slide 61 Enhanced BA Mechanism Aggregation frame MD D1D2D3 D4 Initiator Responder Compressed BA SIFS  The originator may omit the inclusion of a BAR frame in an aggregated frame (Implicit BAR).  Defines a compressed variant of the 802.11e BA MPDU (Compressed BA). ■ Support for non-fragmented BA. This reduces the bitmap size to 1 bit per MSDU. ■ Truncation of the bitmap to reduce the number of MSDUs acknowledged in the bitmap. CompressedNon-FragNumMSDU_M1TID 1 – 128 Frame Control Duration /ID RATA BA Control BA Starting Seq. Control BlockAckBitmapFCS BA Bitmap size is fixed through BA setup.

62. doc.: IEEE 802.11-04/888r3 Submission November 2004 Syed Aon Mujtaba, Agere Systems, et. al.Slide 62 MAC Architecture

63. doc.: IEEE 802.11-04/888r3 Submission November 2004 Syed Aon Mujtaba, Agere Systems, et. al.Slide 63 CC 27/28 Performance

64. doc.: IEEE 802.11-04/888r3 Submission November 2004 Syed Aon Mujtaba, Agere Systems, et. al.Slide 64 Selected MAC CC Performance CC#NameResultHCCA 2x2x202x2x40 CC3List of goodput results for usage models 1, 4 and 6. SS1 (Mbps)55.3883.92 SS1 bisn/a100.43 SS461.52142.12 SS4 bisn/a160.12 SS645.5166.00 SS6 bisn/a96.24 CC18HT Usage Models Supported Non-QoS (Measured aggregate throughput / offered aggregate throughput) SS1 (Mbps/ratio) 2.87/0.0931.43/0.24 SS452.37/0.11 133.01/0.29 SS60.73/0.0321.24/1 CC19HT Usage Models Supported (number of QoS flows that meet their QoS requirements) SS117 of 17 SS418 of 18 SS639 of 39 CC58HT Spectral Efficiencybps/Hz6.37.09

65. doc.: IEEE 802.11-04/888r3 Submission November 2004 Syed Aon Mujtaba, Agere Systems, et. al.Slide 65 MAC Summary  Baseline Features ■ MAC Level Frame Aggregation ■ QoS Support (802.11e)  Additional MAC Efficiency ■ Header Compression ■ Multi-Destination Aggregation ■ Bi-Directional Data Flow ■ Block ACK Compression  Legacy Compatible Protection Mechanisms ■ Long NAV ■ Pairwise Spoofing ■ Single Ended Spoofing  Scalable Channel Management ■ 20/40 MHz Operating Modes

66. doc.: IEEE 802.11-04/888r3 Submission November 2004 Syed Aon Mujtaba, Agere Systems, et. al.Slide 66 List of References  IEEE 802.11-04/887, "TGnSync Proposal Summary"  IEEE 802.11-04/888, "TGnSync Proposal“ (This document)  IEEE 802.11-04/889, "TGnSync Proposal Technical Specification"  IEEE 802.11-04/890, "TGnSync Proposal FRCC Compliance"  IEEE 802.11-04/891, "TGnSync Proposal PHY Results"  IEEE 802.11-04/892, "TGnSync Proposal MAC Results"  IEEE 802.11-04/893, "TGnSync Proposal MAC1 Simulation Results"  IEEE 802.11-04/894, "TGnSync Proposal MAC2 Simulation Results"  IEEE 802.11-04/895, "TGnSync Proposal MAC Simulation Methodology"  You may also direct questions to info@tgnsync.org  For additional details, refer to http://www.tgnsync.org

67. doc.: IEEE 802.11-04/888r3 Submission November 2004 Syed Aon Mujtaba, Agere Systems, et. al.Slide 67 Modifications since Sep 2004  Removed Options ■ Reed Solomon coding ■ 7/8 code rate ■ 400ns GI  Added ■ 7/8 code rate as mandatory ■ 400ns GI as mandatory (800ns is already mandatory)  Removed ■ TSPEC negotiation ■ Packet loss priority  Added ■ Block ACK Compression PHY MAC

68. doc.: IEEE 802.11-04/888r3 Submission November 2004 Syed Aon Mujtaba, Agere Systems, et. al.Slide 68 Key Features  Scalable PHY & MAC Architecture  20 and 40 MHz channels – fully interoperable  Data rate scalable to 630 Mbps  Legacy interoperability – all modes  Robust preamble  Transmit beamforming  Robust frame aggregation  Bi-directional data flow  Fast link adaptation

69. doc.: IEEE 802.11-04/888r3 Submission November 2004 Syed Aon Mujtaba, Agere Systems, et. al.Slide 69 Glossary