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niWLANG_SetMappingMatrixType

NI WLAN Generation Toolkit 17.0 Help

Edition Date: May 2017

Part Number: 373725G-01

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int32 __stdcall niWLANG_SetMappingMatrixType (niWLANGenerationSession session, char channelString[], int32 mappingMatrixType);

Purpose

Specifies the mapping matrix type for mapping space-time streams to transmit channels as defined in section 20.3.11.10.1 of IEEE Standard 802.11n-2009.

Note   If you set this function to values other than NIWLANG_VAL_MAPPING_MATRIX_TYPE_DIRECT, the number of transmit channels must be greater than or equal to the sum of the number of space-time streams and the NIWLANG_NUMBER_OF_EXTENSION_SPATIAL_STREAMS attribute if the NIWLANG_STANDARD attribute is set to NIWLANG_VAL_STANDARD_80211N_MIMO_OFDM.

Parameters

Input
Name Type Description
session niWLANGenerationSession Specifies the niWLAN generation session.
channelString char[] Set this parameter to "" (empty string) or NULL.
mappingMatrixType int32

Specifies the mapping matrix type for mapping space-time streams to transmit channels.

The default value is NIWLANG_VAL_MAPPING_MATRIX_TYPE_DIRECT.

NIWLANG_VAL_MAPPING_MATRIX_TYPE_DIRECT (0) Specifies direct mapping for space-time streams.

The direct mapping matrix is given by NTx = NSTS. Direct mapping matrix is derived by taking the subset (NSTS * NSTS) of the 8 × 8 identity matrix.

where   NTx is the number of transmit channels
            NSTS is the number of space-time streams. If the NIWLANG_STANDARD attribute is set to NIWLANG_VAL_STANDARD_80211N_MIMO_OFDM, this value is determined by the modulation and coding scheme (MCS) index and space-time block coding (STBC) index

The following is an example of a 4 × 4 identity matrix.

NIWLANG_VAL_MAPPING_MATRIX_TYPE_HADAMARD (1) Specifies Hadamard mapping for space-time streams and the extension spatial streams.

The Hadamard mapping matrix is of size NTx * (NSTS + NESS), where NTx ≥ (NSTS + NESS), if the NIWLANA_STANDARD attribute is set to NIWLANG_VAL_STANDARD_80211N_MIMO_OFDM. The Hadamard mapping matrix is of size NTx * (NSTS + NESS), where NTx ≥ (NSTS if the NIWLANA_STANDARD attribute is set to NIWLANG_VAL_STANDARD_80211AC_MIMOOFDM, NIWLANG_VAL_STANDARD_80211AH_MIMO_OFDM, NIWLANG_VAL_STANDARD_80211AX_MIMO_OFDM. Hadamard mapping matrix is derived by taking the subset ((NTx x (NSTS + NESS)) of the 8 × 8 Hadamard matrix.

where   NTx is the number of transmit channels
            NSTS is the number of space-time streams. If the NIWLANA_STANDARD attribute is set to NIWLANG_VAL_STANDARD_80211N_MIMO_OFDM, the value of NSTS is determined by the MCS index and STBC index
            NESS is the number of extension spatial streams

The following matrix is an example of a 4 × 4 matrix.

NIWLANG_VAL_MAPPING_MATRIX_TYPE_FOURIER (2) Specifies Fourier mapping for space-time streams and the extension spatial streams.

The Fourier mapping matrix is given by

where   n= 0 … (N -1)
            N = NTx, where NTx is the number of transmit channels
            k = 0...((NSTS + NESS) - 1), if the NIWLANA_STANDARD attribute is set to NIWLANG_VAL_STANDARD_80211N_MIMO_OFDM, or k = 0...((NSTS - 1) if the NIWLANA_STANDARD attribute is set to NIWLANG_VAL_STANDARD_80211AC_MIMOOFDM, NIWLANG_VAL_STANDARD_80211AH_MIMO_OFDM, NIWLANG_VAL_STANDARD_80211AX_MIMO_OFDM, NSTS is the number of space-time streams. If the NIWLANA_STANDARD attribute is set to NIWLANG_VAL_STANDARD_80211N_MIMO_OFDM, this value is determined by MCS index and STBC index, and NESS is the number of extension spatial streams

The following matrices are examples of 2 × 2, 3 × 3 and 4 × 4 matrices.

NIWLANG_VAL_MAPPING_MATRIX_TYPE_USER_DEFINED (3) Specifies user-defined mapping for space-time streams and extension spatial steams. You can set this matrix using the niWLANG_SetMappingMatrix function.

Return Value

Name Type Description
status int32 Returns the status code of this operation. The status code either indicates success or describes an error or warning condition. Examine the status code from each call to the function to determine if an error occurred.

To obtain a text description of the status code, call the niWLANG_GetErrorString function.

The general meaning of the status code is as follows:

Value Meaning
0 Success
Positive Values Warnings
Negative Values Errors

 

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