Explicit feedback with sounding packet May 2006 doc.: IEEE 802.11-06/1524r0 September 2006 Explicit feedback with sounding packet Date: 2006-09-19 Authors: 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 <http:// ieee802.org/guides/bylaws/sb-bylaws.pdf>, 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 <stuart.kerry@philips.com> 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 <patcom@ieee.org>. Deric Waters, Texas Instruments Deric Waters, Texas Instruments

Flaws in Pilot Definition for MCS 32 September 2006 Flaws in Pilot Definition for MCS 32 Pilot values for the second space-time stream are undefined. Text and equation (20-55) [D1.0] are inconsistent. Pg. 209, line 5-6 [D1.0], “The pilot values are the same as the values on bins -21, -7, 7, 21 in the 20MHz mode, repeated on the 6 negative and positive bins and rotated in the upper bins.” Implies that pilot values depend on the OFDM symbol number, n. (20-55) defines pilot values from 17.3.5.9. The pilot values are the same for every OFDM symbol (i.e. not a function of n). Deric Waters, Texas Instruments

Eq (20-55) September 2006 , where , as defined in Clause 17.3.5.9. Deric Waters, Texas Instruments

Pilot Values in 20 MHz Transmission September 2006 Pilot Values in 20 MHz Transmission NSTS iSTS 1 -1 2 n is the OFDM symbol number. Deric Waters, Texas Instruments

Two Possible Solutions September 2006 Two Possible Solutions Modify equation to implement the text. HT duplicate and 20 MHz HT modes have the same pilot values (depends on the OFDM symbol number). Modify the text to match the equation. HT duplicate mode (non-STBC) has same pilot values as non-HT duplicate (independent of the OFDM symbol number). Both solutions require defining the pilot values for the STBC mode. Deric Waters, Texas Instruments

Straw Poll #1 Yes: No: Don’t care: September 2006 Straw Poll #1 Should MCS 32 with NSTS=1 have the same pilot values as non-HT duplicate (same as legacy 20 MHz transmission)? Yes: No: Don’t care: Deric Waters, Texas Instruments

Straw Poll #2 For MCS 32 with STBC, September 2006 Straw Poll #2 For MCS 32 with STBC, Pilot values of first space-time stream should match pilot values from non-HT duplicate mode. Pilot values of second space-time stream are a static orthogonal sequence. Pilot values of both space-time streams match the pilot values of 20 MHz transmission. Option 1: Option 2: Don’t care: Deric Waters, Texas Instruments