HE-MU
- Bit Number
- 24
- Structure
-
- u16 flags1
- u16 flags2
- u8 RU_channel1[4]
- u8 RU_channel2[4]
- Required Alignment
- 2
- Unit(s)
- none
This field contains data related to PPDUs of HE_MU type that wasn’t already captured in the regular HE field. This is the common data (from HE-SIG-A and HE-SIG-B), the per-user data can be captured in the HE-MU-other-user field.
Channel 1 / Channel 2 usage and RU byte mapping
The “Channel 1” and “Channel 2” specific fields (respectively “channel1 and channel2” on the RU fields) are used in the following way:
- Channel 1’s known field is always used, use it to indicate how much data of channel 1 was captured
- Channel 2’s known field is only used for 40 MHz and higher, use it to indicate how much data of channel 2 was captured, it should be set to 0 (for unknown) for 20 MHz
The RU octets in the arrays (“RU_channel1” and “RU_channel2”) represent the RU allocation index according to Table 28-26 (“RU allocation subfield”).
The following tables map the RU fields to tone ranges:
Channel 1 tones depending on known field
If known=0, no data was reported (e.g. HW not capable, or CRC error on one of the SIG-Bs).
If known=1, the data is according to the following table, bandwidth being from the “bandwidth from Bandwidth field in HE-SIG-A” flags 2 field.
| RU idx | bw=0 (20 MHz) | bw=1 (40 MHz) | bw=2 (80 MHz) | bw=3 (160 MHz) |
| RU[0] | -122:122 | -244:-3 | -500:-259 | -1012:-771 |
| RU[1] | / | / | 17:258 | -495:-254 |
| RU[2] | / | / | / | 12:253 |
| RU[3] | / | / | / | 529:770 |
| Center 26-tone | / | / | -16:-4, 4:16 | -528:-516, -508:-496 |
Channel 2 tones depending on known field
If known=0, no data was reported (e.g. HW not capable, or CRC error on one of the SIG-Bs).
If known=1, the data is according to the following table, bandwidth being from the “bandwidth from Bandwidth field in HE-SIG-A” flags 2 field.
| RU idx | bw=0 (20 MHz) | bw=1 (40 MHz) | bw=2 (80 MHz) | bw=3 (160 MHz) |
| RU[0] | / | 3:244 | -258:-17 | -770:529 |
| RU[1] | / | / | 259:500 | -253:-12 |
| RU[2] | / | / | / | 254:495 |
| RU[3] | / | / | / | 771:1012 |
| Center 26-tone | / | / | / | 496:508, 516:528 |
flags1
0x000f |
SIG-B MCS (from SIG-A) |
0x0010 |
SIG-B MCS known |
0x0020 |
SIG-B DCM (from SIG-A) |
0x0040 |
SIG-B DCM known |
0x0080 |
(Channel 2) Center 26-tone RU bit known |
0x0100 |
Channel 1 RUs known (which depends on BW) |
0x0200 |
Channel 2 RUs known (which depends on BW) |
0x0c00 |
(reserved) |
0x1000 |
(Channel 1) Center 26-tone RU bit known |
0x2000 |
(Channel 1) Center 26-tone RU value |
0x4000 |
SIG-B Compression known |
0x8000 |
# of HE-SIG-B Symbols/MU-MIMO Users known |
flags2
0x0003 |
bandwidth from Bandwidth field in HE-SIG-A (0 - 20 MHz, …, 3 - 160/80+80 MHz) |
0x0004 |
bandwidth from Bandwidth field in HE-SIG-A known |
0x0008 |
SIG-B compression from SIG-A |
0x00f0 |
# of HE-SIG-B Symbols - 1 or # of MU-MIMO Users - 1 from SIG-A |
0x0300 |
preamble puncturing from Bandwidth field in HE-SIG-A (0 - non-puncturing, 1 - punctured secondary 20 MHz (in primary 80 MHz if applicable), 2 - punctured but primary 40 MHz is present (in primary 80 MHz if applicable) |
0x0400 |
preamble puncturing from Bandwidth field in HE-SIG-A known |
0x0800 |
(Channel 2) Center 26-tone RU value |
0xf000 |
(reserved) |
RU
See the discussion above regarding Channel 1/Channel 2 RU field usage.