SIG Fields Design of Long Preamble Month Year doc.: IEEE 802.11-yy/xxxxr0 July 2012 SIG Fields Design of Long Preamble Date: 2012-07-12 Authors: Yongho Seok, LG Electronics John Doe, Some Company

Authors: July 2012 Month Year doc.: IEEE 802.11-yy/xxxxr0 Yongho Seok, LG Electronics John Doe, Some Company

July 2012 Authors: Yongho Seok, LG Electronics

July 2012 Motivation In IEEE 802.11 TGah meeting, the preamble names has been changed from SU/MU preamble to Short/Long preamble However, SIG fields table (R.3.2.1.1.E ) has not been correctly updated Because TGah supports three preamble formats for >=2 MHz PHY, SIG field table also should be updated with three SIG field columns Yongho Seok, LG Electronics

Beam-change Indication July 2012 Proposal for R.3.2.1.1.E.1 Short preamble Long preamble SU MU SU/MU Indication - 1 Length / Duration 9 MCS 4 BW 2 Aggregation STBC Coding 5 SGI GID 6 Nsts 8 PAID Ack Indication Smoothing Beam-change Indication Reserved 3 CRC Tail Total 48 SU MU Length / Duration 9 MCS 4 BW 2 Aggregation 1 STBC Coding 5 SGI GID 6 Nsts 8 PAID Ack Indication 2   Reserved CRC Tail Total 48 Yongho Seok, LG Electronics

Proposal for R.3.2.1.1.E.1 Changes July 2012 Proposal for R.3.2.1.1.E.1 Changes Smoothing/Bean-change Indication field is included in SIGA [1] SU/MU Indication field is used in Long preamble for indicating the SU/MU frame type Yongho Seok, LG Electronics

July 2012 Definition of SIG-B SIG-B is used in the long preamble to convey the MCS information for MU-MIMO transmission (different MCS for different users). We propose to re-define this symbol for SU transmission as an exact repetition of D-LTF1. This will enable improved channel estimation for the important cases of SU beamforming or open loop with one spatial stream (and to a lesser extent multiple streams).   BW 2 MHz 4 MHz 8 MHz 16 MHz MCS 4 Tail 6 CRC 8 Reserved 9 11 Total 26 27 29   BW 2 MHz 4 MHz 8 MHz 16 MHz Reserved 26 27 29 Total <SU> <MU> Yongho Seok, LG Electronics

Definition of SIG-B Proposals July 2012 Definition of SIG-B Proposals R.3.2.1.1.E bullet 2: replace “2MHz SIGB (long preamble)” with “For MU-MIMO transmission the 2MHz SIGB content is as shown in the following table. For SU-MIMO transmission the SIGB symbol is identical to D-LTF1.” R.3.2.A bullet 4: replace the sentence starting with “n=0,1,2,…is the symbol index” with “n=0,1,2,…is the symbol index, continuously counted from the 1st Data symbol for short preamble and long preamble when in SU mode, and from SIGB for long preamble when in MU mode” R.3.2.1.D: The draft specification shall use the 4 LSB of the 11n HTSIG field 8-bit CRC for the 4-bit CRC in 11ah 2MHz and 1MHz SIG(A) fields, and use the same 11n HTSIG field 8-bit CRC in SIGB field of the >=2MHz long preamble when in MU mode Yongho Seok, LG Electronics

July 2012 References [1] IEEE 802.11-12/0825r0, Smoothing bit and beam_change indication bit Yongho Seok, LG Electronics

Beam-change Indication July 2012 Straw Poll 1 Short preamble Long preamble SU MU SU/MU Indication - 1 Length / Duration 9 MCS 4 BW 2 Aggregation STBC Coding 5 SGI GID 6 Nsts 8 PAID Ack Indication 2   Smoothing Beam-change Indication Reserved 3 CRC Tail Total 48 Do you support the following SIGA fields design for >= 2MHz PHY? Yongho Seok, LG Electronics

July 2012 Straw Poll 2 Do you support the following modification of SIGB fields for >= 2MHz PHY? R.3.2.1.1.E bullet 2: replace “2MHz SIGB (long preamble)” with “For MU-MIMO transmission the 2MHz SIGB content is as shown in the following table. For SU-MIMO transmission the SIGB symbol is identical to D-LTF1.” R.3.2.A bullet 4: replace the sentence starting with “n=0,1,2,…is the symbol index” with “n=0,1,2,…is the symbol index, continuously counted from the 1st Data symbol for short preamble and long preamble when in SU mode, and from SIGB for long preamble when in MU mode” R.3.2.1.D: The draft specification shall use the 4 LSB of the 11n HTSIG field 8-bit CRC for the 4-bit CRC in 11ah 2MHz and 1MHz SIG(A) fields, and use the same 11n HTSIG field 8-bit CRC in SIGB field of the >=2MHz long preamble when in MU mode Yongho Seok, LG Electronics