1. doc.: IEEE 802.11-05/0418r0 Submission May 2005 Syed Aon Mujtaba, Agere Systems, et. al.Slide 1 PHY Updates to TGn Sync Proposal Notice: This document has been prepared to assist IEEE 802.11. It is offered as a basis for discussion and is not binding on the contributing individual(s) or organization(s). The material in this document is subject to change in form and content after further study. The contributor(s) reserve(s) the right to add, amend or withdraw material contained herein. Release: The contributor grants a free, irrevocable license to the IEEE to incorporate material contained in this contribution, and any modifications thereof, in the creation of an IEEE Standards publication; to copyright in the IEEE’s name any IEEE Standards publication even though it may include portions of this contribution; and at the IEEE’s sole discretion to permit others to reproduce in whole or in part the resulting IEEE Standards publication. The contributor also acknowledges and accepts that this contribution may be made public by IEEE 802.11. Patent Policy and Procedures: The contributor is familiar with the IEEE 802 Patent Policy and Procedures, including the statement "IEEE standards may include the known use of patent(s), including patent applications, provided the IEEE receives assurance from the patent holder or applicant with respect to patents essential for compliance with both mandatory and optional portions of the standard." Early disclosure to the Working Group of patent information that might be relevant to the standard is essential to reduce the possibility for delays in the development process and increase the likelihood that the draft publication will be approved for publication. Please notify the Chair as early as possible, in written or electronic form, if patented technology (or technology under patent application) might be incorporated into a draft standard being developed within the IEEE 802.11 Working Group. If you have questions, contact the IEEE Patent Committee Administrator at.http:// ieee802.org/guides/bylaws/sb-bylaws.pdfstuart.kerry@philips.compatcom@ieee.org Date: 2005-05-16 Author NameCompanyAddressPhoneEmail Syed Aon Mujtaba Agere Systems 555 Union Blvd., Allentown, PA 18109, USA +1 610 712 6616mujtaba@agere.com

2. doc.: IEEE 802.11-05/0418r0 Submission May 2005 Syed Aon Mujtaba, Agere Systems, et. al.Slide 2 Additional Authors Jeff Gilbert, Won Joon ChoiAtheros Eldad Perahia, Brian HartCisco Sumei SunInfocomm Steve Shellhammer, Assaf KasherIntel Eldad ZeiraInterdigital Hui-Ling LouMarvell Andy MolishMitsubishi Alek PurkovicNortel Kiyotaka KobayashiPanasonic Pen Li, Monisha Gosh, Job OostveenPhilips John Ketchum, Bjorne BjerkeQualcomm DJ Lee, Chiu NgoSamsung Seigo NakaoSanyo Tomoya YamauraSony Daisuke Takeda, Darren McNamara, Tsuguhide AokiToshiba Mike FaulknerWavebreaker

3. doc.: IEEE 802.11-05/0418r0 Submission May 2005 Syed Aon Mujtaba, Agere Systems, et. al.Slide 3 Abstract  This document describes the PHY updates to the TGn Sync complete proposal’s submission to IEEE 802.11 TGn since the March 2005 IEEE meeting

4. doc.: IEEE 802.11-05/0418r0 Submission May 2005 Syed Aon Mujtaba, Agere Systems, et. al.Slide 4 Summary of PHY Architecture  Mandatory features: ■ Support for 1 and 2 spatial streams in 20MHz ■ Channel coding rates: 1/2, 2/3, 3/4, and 5/6 ■ Modulations: BPSK, QPSK, 16QAM, 64QAM ■ Support for Rx assisted Rate Control ■ Guard Interval: 800ns  Optional features: ■ 40 MHz channelizations ■ Transmit beamforming (Tx BF) - beamsteering ■ Guard Interval: 400ns ■ Advanced coding (LDPC) ■ Support for 3 and 4 spatial streams 130 Mbps in 2x2x20 600 Mbps in 4x4x40 Superior performance  Enhanced user experience Market driven arch  Enable broad adoption

5. doc.: IEEE 802.11-05/0418r0 Submission May 2005 Syed Aon Mujtaba, Agere Systems, et. al.Slide 5 Feedback from TGn body  The PHY team received more than 250 comments on its PHY architecture  Major PHY catergories included: ■ preamble ■ Transmit beamforming ■ MCS modes ■ LDPC

6. doc.: IEEE 802.11-05/0418r0 Submission May 2005 Syed Aon Mujtaba, Agere Systems, et. al.Slide 6 PHY Modifications after Atlanta (March 2005)  Preamble ■ Reduced the length of the mixed mode preamble  Number of MCS modes ■ reduced the number of mandatory modes to 16 ■ Half-GI has been made optional  Made Calibration optional ■ TxBF is optional at both the Tx and the Rx  Basic & Advanced modes merged into one TxBF mode

7. doc.: IEEE 802.11-05/0418r0 Submission May 2005 Syed Aon Mujtaba, Agere Systems, et. al.Slide 7 Preamble Format Legacy Compatible Preamble Fields HT-SIG Field HT Short Training Field HT Long Training Fields 20 us8 us2.4 usvariable length (depends on N SS or N ANT ) Reduced the length

8. doc.: IEEE 802.11-05/0418r0 Submission May 2005 Syed Aon Mujtaba, Agere Systems, et. al.Slide 8 Legacy Compatible Preamble  Format remains unchanged from before L-STFGI2L-LTS GIL-SIG 8 us1.6us3.2 us 0.8us  The legacy compatible preamble may be transmitted either from one antenna or from multiple antennas using CDD

9. doc.: IEEE 802.11-05/0418r0 Submission May 2005 Syed Aon Mujtaba, Agere Systems, et. al.Slide 9 HT-SIG field  Format remains unchanged from before GIHT-SIG 1GIHT-SIG 2 4us  To achieve robustness and range, HT-SIG is transmitted using R=1/2 BPSK

10. doc.: IEEE 802.11-05/0418r0 Submission May 2005 Syed Aon Mujtaba, Agere Systems, et. al.Slide 10 HT-STF  Format remains unchanged from before Tone Interleaved 2.4 us  Tone interleaving across the transmit antenna array provides the most accurate AGC measurement

11. doc.: IEEE 802.11-05/0418r0 Submission May 2005 Syed Aon Mujtaba, Agere Systems, et. al.Slide 11 HT-LTF GIHT-LTS GI Tone interleaved HT-LTS Tone interleaved HT-LTS GI Tone interleaved HT-LTS GI Tone interleaved HT-LTS Tone interleaved HT-LTS GI Tone interleaved HT-LTS GI Tone interleaved HT-LTS GI Tone interleaved HT-LTS Tone interleaved HT-LTS GI Tone interleaved HT-LTS GI Tone interleaved HT-LTS GI Tone interleaved HT-LTS N SS =1 N SS =2 N SS =3 N SS =4 7.2us 4us

12. doc.: IEEE 802.11-05/0418r0 Submission May 2005 Syed Aon Mujtaba, Agere Systems, et. al.Slide 12 HT-LTF  The first HT-LTF field contains a repeated symbol: ■ further refinement of frequency offset estimation – helpful especially when frequency transients are present ■ accurate noise power estimation after the AGC  Subsequent HT-LTF fields contain only one OFDM symbol ■ simulation results show minimal degradation in channel estimation accuracy and PER

13. doc.: IEEE 802.11-05/0418r0 Submission May 2005 Syed Aon Mujtaba, Agere Systems, et. al.Slide 13 Half-GI  We have made Half-GI optional  Thus, the mandatory MCS set only contains 800ns GI  Half-GI is a simple technique that increases throughput by 11%  Our implementation of Half-GI does not call for a change in TX and/or RX filters ■ instead, we recommend use of Half-GI when delay spread is small, such as in Channel Model B – a common occurance in home environments

14. doc.: IEEE 802.11-05/0418r0 Submission May 2005 Syed Aon Mujtaba, Agere Systems, et. al.Slide 14 Mandatory MCS modes  The total number of mandatory MCS is 16: ■ R=1/2, 2/3, 3/4, and 5/6 ■ BPSK, QPSK, 16-QAM, and 64-QAM ■ 1 and 2 spatial streams ■ 20MHz channelization ■ 800ns GI

15. doc.: IEEE 802.11-05/0418r0 Submission May 2005 Syed Aon Mujtaba, Agere Systems, et. al.Slide 15 Calibration  We have made calibration optional at both the Tx and the Rx ■ Hence, Transmit Beamforming (TxBF) is fully optional at both the Tx and the Rx  Calibration of radios is recommended if reciprocity is used for calculating the channel state information (CSI)  The Tx needs CSI to calculate beam-steering matrices

16. doc.: IEEE 802.11-05/0418r0 Submission May 2005 Syed Aon Mujtaba, Agere Systems, et. al.Slide 16 Basic vs Advanced BF  We have eliminated the distinction between basic and advanced BF  Technical specification has only one Transmit Beamforming mode  In this TxBF mode, the transmitter maps the spatial streams to antennas using beam- steering matrices, which are calculated using the CSI

17. doc.: IEEE 802.11-05/0418r0 Submission May 2005 Syed Aon Mujtaba, Agere Systems, et. al.Slide 17 Unified Datapath for All Modes Scrambler FEC parser Interleaver QAM mapper QAM mapper QAM mapper QAM mapper iFFT insert GI window insert GI window insert GI window insert GI window Interleaver analog & RF analog & RF analog & RF analog & RF PSDU Direct Map Simple map for N SS < N Tx Spatial Spreading Walsh + CDD Tx BF SVD V Optimal spatial diversity & array gain

18. doc.: IEEE 802.11-05/0418r0 Submission May 2005 Syed Aon Mujtaba, Agere Systems, et. al.Slide 18 Summary of PHY Architecture Open Loop SDM RX assisted Rate Control 2 Spatial Streams 20 MHz  130 Mbps Robustness Enhancement Closed Loop Tx BF 4 Spatial Streams Throughput Enhancement Conv. Coding LDPC Robustness Enhancement  600 Mbps Mandatory Optional 40 MHz Throughput Enhancement 800ns GI400ns GI