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EHT MU Transmission

Transmission Mode Options

The options for extremely high-throughput multi-user (EHT MU) transmissions are:

  • Orthogonal frequency-division multiple access (OFDMA)

  • Full-band multi-user multiple-input/multiple-output (MU-MIMO)

  • Mixed OFDMA and MU-MIMO

The transmission mode depends on the property you set when you create a wlanEHTMUConfig object.

  • To specify OFDMA or a mix of OFDMA and MU-MIMO, set the AllocationIndex property when you create the object.

  • To specify full-band MU-MIMO, set the ChannelBandwidth property when you create the object.

The 802.11be Waveform Generation example introduces the concepts associated with EHT transmission modes, resource unit (RU) and multiple resource unit (MRU) allocation, and parameterization.

An RU is a group of 26, 52, 106, 242, 484, 968, 996, 1992, or 3984 subcarriers defining an allocation unit in time and frequency. An MRU is a group of RUs joined together. In this diagram, the picture on the left shows only RUs, and the picture on the right shows RUs and MRUs.

Comparison of RU and MRU allocations

Allocation Index

When you create an OFDMA or mixed wlanEHTMUConfig object, you must specify the value of the AllocationIndex property. Once the object is created, the AllocationIndex property is read-only.

The AllocationIndex property defines the number of RUs or MRUs, their sizes, and the number of users assigned to them.

  • Set the AllocationIndex property as an integer to specify a channel bandwidth of 20 MHz.

  • Set the AllocationIndex property as a row vector of length 2, 4, 8, or 16 to specify a respective channel bandwidth of 40, 80, 160, or 320 MHz. The vector's length is equal to the number of 20 MHz subchannels.

  • Set the AllocationIndex property as an M-by-N matrix to specify a channel bandwidth of 160 or 320 MHz. M is the number of 80 MHz segments and N is the number of 20 MHz subchannels.

You can signal punctured subchannels in OFDMA transmissions with a channel bandwidth of 80 MHz or above. To signal a punctured 20 MHz subchannel, set the corresponding element to 26. To signal larger punctured subchannels, set corresponding adjacent elements to 26.

The values specified in the AllocationIndex property correspond to the 9-bit indices for each 20 MHz subchannel in the first column of Table 36-34 in [1].

This table lists the allocation indices and corresponding RU assignments for 20 MHz subchannels and RUs with at most 242 tones. The table shows the number of tones per RU and the number of users assigned for each allocation index.

This table lists the allocation indices with a corresponding RU assignment that includes MRUs.

This table lists RU allocation and EHT-SIG user signaling for 242-, 484-, 996-, and 2x996-tone RUs.

This table lists MRU allocation and EHT-SIG user signaling for allocations with a channel bandwidth of 80 MHz or greater.

This table shows allocation index and channel bandwidth options required to specify transmission type for all channel bandwidths.

Transmission Type20 MHz Transmission40 MHz Transmission80 MHz Transmission160 MHz Transmission320 MHz Transmission
Full-bandwidth MU-MIMO

wlanEHTMUConfig("CBW20", NumUsers=a)

Specify a as an integer in the interval [1, 8].

wlanEHTMUConfig("CBW40", NumUsers=a)

Specify a as an integer in the interval [1, 8].

wlanEHTMUConfig("CBW80", NumUsers=a)

Specify a as an integer in the interval [1, 8].

wlanEHTMUConfig("CBW160", NumUsers=a)

Specify a as an integer in the interval [1, 8].

wlanEHTMUConfig("CBW320", NumUsers=a)

Specify a as an integer in the interval [1, 8].

For puncturing, use wlanEHTMUConfig("CBWx", PuncturedChannelFieldValue = y).

Specify x as 80, 160, or 320. Specify y as an integer in the interval [0, 24].

To enable EHT DUP mode, use wlanEHTMUConfig("CBWx", EHTDUPMode = true).

Specify x as 80, 160, or 320.

OFDMA

wlanEHTMUConfig(a)

Specify a as an integer in one of the intervals [0, 25] or [32, 55].

wlanEHTMUConfig([a b])

Specify a and b as integers in one of the intervals [0, 27] or [32, 55].

wlanEHTMUConfig([a b c d])

Specify the vector entries as integers in one of the intervals [0, 27] or [32, 55].

wlanEHTMUConfig([a b c d e f g h])

Specify the vector entries as integers in one of the intervals [0, 27] or [32, 55].

wlanEHTMUConfig([a b c d e f g h i j k l m n o p])

Specify the vector entries as integers in one of the intervals [0, 27] or [32, 55].

Mixed OFDMA and MU-MIMON/A

wlanEHTMUConfig([a b])

Specify a and b as integers in the interval [0, 27], 29, or integers in one of the intervals [32, 55] or [64, 79].

wlanEHTMUConfig([a b c d])

Specify the vector entries as integers in one of the intervals [0, 30], [32, 55], or [64, 127].

wlanEHTMUConfig([a b c d e f g h])

Specify the vector entries as integers in one of the intervals [0, 30], [32, 55], or [64, 159].

wlanEHTMUConfig([a b c d e f g h i j k l m n o p])

Specify the vector entries as integers in one of the intervals [0, 30], [32, 55], or [64, 303].

Related Topics

References

[1] IEEE® P802.11be™/D1.5. “Part 11: Wireless LAN Medium Access Control (MAC) and Physical Layer (PHY) Specifications. Amendment 8: Enhancements for Extremely High Throughput (EHT).” Draft Standard for Information Technology — Telecommunications and Information Exchange between Systems — Local and Metropolitan Area Networks — Specific Requirements.