wlanHEMUConfig Properties

Define parameter values for multiuser HE format packet

The wlanHEMUConfig object specifies the transmission properties for the multiuser IEEE® 802.11™ high efficiency (HE) format physical layer (PHY) packet.

After you create a wlanHEMUConfig object, use dot notation to change or access the object parameters. For example:

Create a wlanHEMUConfig object. Modify the default setting for the GuardInterval property.

cfgHEMU = wlanHEMUConfig(0);
cfgHEMU.GuardInterval = 1.6;

Properties of each resource unit (RU), specified as a cell array. When you create a wlanHEMUConfig object, the RU cell array is configured based on the defined AllocationIndex input argument.

Properties of Each RU Cell Array Element

Power boost factor, specified as a scalar in the interval [0.5, 2].

Data Types: double

Spatial mapping scheme, specified as 'Direct', 'Hadamard', 'Fourier', or 'Custom'. The default value 'Direct' applies when NT and NSTS_Total are equal. NT is the number of transmit antennas and NSTS_Total is the sum of space-time streams for all users assigned to this RU.

Data Types: char | string

Spatial mapping matrix, specified as a scalar, matrix, or 3-D array. Use this property to rotate and scale the output vector of the constellation mapper. The spatial mapping matrix is used for beamforming and mixing space-time streams over the transmit antennas.

  • When specified as a scalar, that scalar value applies to all the subcarriers.

  • When specified as a matrix, its size must be NSTS_Total-by-NT. The spatial mapping matrix applies to all the subcarriers. NSTS_Total is the sum of space-time streams for all users assigned to this RU, and NT is the number of transmit antennas.

  • When specified as a 3-D array, its size must be NST-by-NSTS_Total-by-NT. NST is the number of occupied subcarriers, as determined by the RU size. Specifically, N ST can be 26, 52, 106, 242, 484, 996, or 1992. NT is the number of transmit antennas and NSTS_Total is the sum of space-time streams for all users assigned to this RU.

The calling function normalizes the spatial mapping matrix for each subcarrier.

Example: [0.5 0.3; 0.4 0.4; 0.5 0.8] represents a spatial mapping matrix with three space-time streams and two transmit antennas.

Dependencies

This property applies only when the SpatialMapping property is set to 'Custom'.

Data Types: double
Complex Number Support: Yes

Enable signaling of a transmission with beamforming, specified as a logical value. Beamforming is signalled when this property is set to true. The SpatialMappingMatrix property specifies the beamforming steering matrix.

Dependencies

This property applies only when the SpatialMapping property is set to 'Custom'.

Data Types: logical

Resource unit size, specified as 26, 52, 106, 242, 484, 996, or 1992.

Note

This property is read-only after the object is created.

Data Types: double

Resource unit index, specified as a positive integer in the interval [1, 74]. This number is used to indicate the location of the RU within the channel.

Note

This property is read-only after the object is created.

Example: In an 80 MHz transmission there are four possible 242 tone RUs, one in each 20 MHz subchannel. RU# 242-1 (Size = 242, Index = 1) is the RU occupying the lowest absolute frequency within the 80 MHz, and RU# 242-4 (Size = 242, Index = 4) is the RU occupying the highest absolute frequency.

Data Types: double

User index number transmitted on this RU, specified as a positive integer in the interval [1, 8]. This number is used to index the appropriate User cell array element within the wlanHEMUConfig object.

Data Types: double

Data Types: cell

User properties of each assignment index, specified as a cell array. When you create a wlanHEMUConfig object, the User cell array is configured based on the defined AllocationIndex input argument.

Properties of Each User

Number of bytes in the A-MPDU pre-EOF padding, specified as a nonnegative integer in the interval [0, 6500531].

APEPLength is used internally to determine the number of OFDM symbols in the data field. For more information, see 802.11 802.11-17/1001r4.

Data Types: double

Modulation and coding scheme (MCS) used in transmitting the current packet, specified as a nonnegative integer in the interval [0, 11].

MCSModulationDual Carrier Modulation (DCM)Coding Rate
0BPSK

0 or 1

1/2
1QPSK

0 or 1

1/2
2

Not applicable

3/4
316-QAM

0 or 1

1/2
43/4
564-QAM

Not applicable

2/3
63/4
75/6
8256-QAM3/4
95/6
101024-QAM3/4
115/6

Data Types: double

Number of space-time streams (NSTS) in the transmission, specified as a positive integer in the interval [1, 8]. The maximum NSTS summed over all users is 8. Additional restrictions are enforced based on spatial configuration as specified in Table 28-1 and 28-27 of IEEE P802.11ax™/D2.0.

Data Types: double

Enable dual carrier modulation (DCM) for HE-data field, specified as a logical value.

Dependencies

DCM can be used only when all of these conditions are satisfied:

  • The MCS property is 0, 1, 3, or 4.

  • The STBC property is not used.

  • The NumSpaceTimeStreams property is less than or equal to 2.

  • The RU object defines a single-user RU.

Data Types: logical

Type of forward error correction coding for the data field, specified as 'LDPC' for low-density parity-check coding or 'BCC' for binary convolutional coding.

Dependencies

The 'BCC' value for ChannelCoding is valid only when all of these conditions are satisfied:

  • The MCS property is not 10 or 11.

  • The RU property is less than or equal to 242.

  • The NumSpaceTimeStreams property is less than or equal to 4.

Data Types: char | string

Station identifier, specified as a nonnegative integer in the interval [0,2047]. This value specifies the STA association identifier (AID) field as defined in IEEE P802.11ax/D2.0, Section 27.11.1. The 11 LSBs of the AID field are used to address the STA. When STAID is set to 2046, the associated RU carries no data.

Data Types: double

RU number, specified as a positive integer in the interval [1, 8]. This number is used to index the appropriate RU objects within the wlanHEMUConfig object.

Note

This property is read-only after the object is created.

Data Types: double

Data Types: cell

Number of transmit antennas, specified as a positive integer in the interval [1, 8].

Data Types: double

Enable space-time block coding (STBC) of the PPDU data field for all users, specified as a logical value. STBC transmits multiple copies of the data stream across assigned antennas.

  • When set to false, STBC is not applied to the data field, and the number of space-time streams is equal to the number of spatial streams.

  • When set to true, STBC is applied to the data field, and the number of space-time streams is double the number of spatial streams.

Dependencies

This property applies only when all of these conditions are satisfied:

  • The NumSpaceTimeStreams property is 2.

  • The DCM property is false for all users.

  • No RU specifies MU-MIMO.

Data Types: logical

Cyclic prefix length, in microseconds, for the data field within a packet, specified as 3.2, 1.6, or 0.8.

Data Types: double

HE-LTF compression mode of HE PPDU, specified as 4, 2, or 1. This value corresponds four times, two times, or one times HE-LTF duration compression mode, respectively. The HE-LTF type is enumerated in Table 28-1 of IEEE 802.11ax/D2.0 as:

  • 1x HE-LTF — For 3.2 μs with a guard interval duration of 0.8 μs or 1.6μs

  • 2x HE-LTF — For 6.4 μs with a guard interval duration of 0.8 μs or 1.6 μs

  • 4x HE-LTF — For 12.8 μs with a guard interval duration of 0.8 μs or 3.2 μs

Data Types: double

Modulation and coding scheme for the HE-SIG-B field, specified as a nonnegative integer in the interval [0, 5].

Data Types: double

Enable DCM for the HE-SIG-B field, specified as a logical value.

Dependencies

This property applies only when the MCS property is 0, 1, 3, or 4.

Data Types: logical

Uplink indication, specified as false or true. Specify UplinkIndication as false to indicate that the PPDU is sent on a downlink transmission. Specify UplinkIndication as true to indicate that the PPDU is sent on an uplink transmission.

Data Types: logical

Basic service set (BSS) color identifier, specified as a nonnegative integer in the interval [0, 63].

Data Types: double

Spatial reuse indication, specified as a nonnegative integer in the interval [0, 15].

Data Types: double

Duration information for TXOP protection, specified as a nonnegative integer in the interval [0, 127]. Except for the first bit, which specifies TXOP length granularity, each bit of the TXOP field of HE-SIG-A is equal to TXOPDuration. Therefore a duration in microseconds must be converted according to the procedure set out in Table 28-18 of [1].

Data Types: double

High Doppler mode indication, specified as a logical value. Set HighDoppler to true to indicate high Doppler in HE-SIG-A.

Dependencies

The true value for this property is valid only when the NumSpaceTimeStreams property is less than or equal to 4 for any RU.

Data Types: logical

HE-data field midamble periodicity in the number of OFDM symbols, specified as 10 or 20.

Dependencies

This property applies only when the HighDoppler property is true.

Data Types: double

Channel bandwidth, specified as 'CBW20', 'CBW40', 'CBW80', or 'CBW160'. When you create a wlanHEMUConfig object, this property is configured based on the defined AllocationIndex input argument.

Note

This property is read-only after the object is created.

Data Types: char | string

Resource unit (RU) allocation index, specified by one, two, four, or eight integer values in the interval [0,223]. You can specify this value as an integer, a vector of integers, a string array, a character vector, or a cell array of character vectors. The format in which you specify these indices depends on how many you are specifying.

  • Specify a single allocation index using one integer in either of these forms:

    • An integer scalar.

    • An 8-bit binary sequence specified as a string or character vector.

  • Specify a multiple allocation indices using two, four, or eight integer values any of these forms:

    • A vector of integers.

    • An 8-bit binary sequence specified as a string array

    • An 8-bit binary sequence specified as a cell array of character vectors

The allocation defines the number of RUs, the size of each RU, and the number of users assigned to each RU. For more information, see OFDMA Allocation Index.

Note

This property is read-only after the object is created.

Data Types: double | char | string | cell

Enable lower center 26-tone RU allocation signaling, specified as a logical value. Using name-value pairs when the object is created, specify LowerCenter26ToneRU,true to enable the lower frequency center 26-tone RU. This property can be set during object creation only.

Dependencies

This property applies only when the AllocationIndex property defines a channel bandwidth of 80 MHz or 160 MHz and does not specify a full bandwidth allocation.

Data Types: logical

Enable upper center 26-tone RU allocation signaling, specified as a logical value. Using name-value pairs when the object is created, specify UpperCenter26ToneRU,true to enable the upper frequency center 26-tone RU. This property can be set during object creation only.

Dependencies

This property applies only when the AllocationIndex property defines a channel bandwidth of 80 MHz or 160 MHz and does not specify a full bandwidth allocation.

Data Types: logical

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References

[1] IEEE Std P802.11ax™/D2.0 Draft Standard for Information technology — Telecommunications and information exchange between systems — Local and metropolitan area networks — Specific requirements — Part 11: Wireless LAN Medium Access Control (MAC) and Physical Layer (PHY) Specifications — Amendment 6: Enhancements for High Efficiency WLAN.

Introduced in R2018b