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

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

3. July 2012
Authors:
Yongho Seok, LG Electronics

4. July 2012
Motivation
In IEEE TGah meeting, the preamble names has been changed from SU/MU preamble to Short/Long preamble
However, SIG fields table (R 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

5. Beam-change Indication
July 2012
Proposal for R 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

6. Proposal for R.3.2.1.1.E.1 Changes
July 2012
Proposal for R 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

7. 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

8. Definition of SIG-B Proposals
July 2012
Definition of SIG-B
Proposals
R 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”
Yongho Seok, LG Electronics

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

10. 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

11. July 2012
Straw Poll 2
Do you support the following modification of SIGB fields for >= 2MHz PHY?
R 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”
Yongho Seok, LG Electronics