NOMA Settings (Custom OFDM)

The NOMA Settings are used to configure 5G demodulation over Custom OFDM Orthogonal Frequency Division Multiplexing: OFDM employs multiple overlapping radio frequency carriers, each operating at a carefully chosen frequency that is Orthogonal to the others, to produce a transmission scheme that supports higher bit rates due to parallel channel operation. OFDM is an alternative tranmission scheme to DSSS and FHSS.. When the Multiple Access Scheme is set to NOMA, the NOMA Settings section of the Multiple Access tab describe the second NOMA user settings.

When the input signal uses NOMA, there are two “users” (transmitters) that simultaneously use the same frequency/time/signal path. Each subcarrier in the received signal contains a weighted sum of the two user signals. In order for the analysis to separate these signals, the modulation formats for both users must be known. The modulation format and boost levels for the “first” NOMA user are specified by the usual QAM Identifiers The QAM Identifiers parameter is specified in the Format tab > QAM Idenifiers text box (Custom OFDM Demod Properties dialog box). and QAM Quadrature Amplitude Modulation Identifier Boost Levels properties on the Format tab, the same as for non-NOMA signals. The modulation format and boost levels for the “second” NOMA user are specified in the NOMA Settings section of the Multiple Access tab

Parameter	Description
QAM Identifier Boost Levels (2nd NOMA user)	This property is an array of values, and works similarly to the QAM Identifier Boost Levels property on the Format tab. There is one value for each identifier in the QAM Identifiers (2nd NOMA user) array. The values are unitless, and are relative to the reference level. The values specify the scaling for the second NOMA user for the corresponding QAM identifier. (The scaling for the first NOMA user is specified by the QAM Identifier Boost Levels property on the Format tab.) A value of 1 means no boosting, while a value of 2 means there is a 6.02 dB boost for the corresponding QAM identifier. If the array is shorter than the QAM Identifiers (2nd NOMA user) array, any values past the end are assumed to be 1. Default: 1
QAM Identifiers (2nd NOMA user	This property is an array of values. It works similarly to and should have the same array length as the QAM Identifiers property on the Format tab. Each entry in this array is an index into the QAM Levels array (on the Format tab), and specifies the QAM identifiers for the second NOMA user. (The QAM identifiers for the first NOMA user are specified by the QAM Identifiers property on the Format tab.) Default: 0, 1, 2, 3, 4, 5

Parameter

Description

This property is an array of values, and works similarly to the QAM Identifier Boost Levels property on the Format tab. There is one value for each identifier in the QAM Identifiers (2nd NOMA user) array. The values are unitless, and are relative to the reference level. The values specify the scaling for the second NOMA user for the corresponding QAM identifier. (The scaling for the first NOMA user is specified by the QAM Identifier Boost Levels property on the Format tab.)

A value of 1 means no boosting, while a value of 2 means there is a 6.02 dB boost for the corresponding QAM identifier. If the array is shorter than the QAM Identifiers (2nd NOMA user) array, any values past the end are assumed to be 1.

Default: 1

This property is an array of values. It works similarly to and should have the same array length as the QAM Identifiers property on the Format tab. Each entry in this array is an index into the QAM Levels array (on the Format tab), and specifies the QAM identifiers for the second NOMA user. (The QAM identifiers for the first NOMA user are specified by the QAM Identifiers property on the Format tab.)

Default: 0, 1, 2, 3, 4, 5