showResourceMapping

Show the subcarrier mapping of the OFDM symbols created by the OFDM modulator System object

Syntax

showResourceMapping(ofdmmod)

showResourceMapping(ofdmmod,ci)

Description

showResourceMapping(ofdmmod) shows a visualization of the subcarrier mapping for the OFDM symbols created by the OFDM modulator System object™. The subcarrier indices are numbered from 1 to ciN_FFT, where N_FFT is the number of FFT points.

showResourceMapping(ofdmmod,ci) uses the values in input ci to number the subcarrier indices that the function displays.

Examples

Construct and Modify OFDM Modulator

An OFDM modulator System object™ can be constructed using default properties. Once constructed, these properties can be modified.

Construct an OFDM modulator.

ofdmMod = comm.OFDMModulator;

Display the properties of the modulator.

disp(ofdmMod)

  comm.OFDMModulator with properties:

               FFTLength: 64
    NumGuardBandCarriers: [2x1 double]
            InsertDCNull: false
          PilotInputPort: false
      CyclicPrefixLength: 16
               Windowing: false
              NumSymbols: 1
     NumTransmitAntennas: 1

Modify the number of subcarriers and symbols.

ofdmMod.FFTLength = 128;
ofdmMod.NumSymbols = 2;

Verify that the number of subcarriers and the number of symbols changed.

disp(ofdmMod)

  comm.OFDMModulator with properties:

               FFTLength: 128
    NumGuardBandCarriers: [2x1 double]
            InsertDCNull: false
          PilotInputPort: false
      CyclicPrefixLength: 16
               Windowing: false
              NumSymbols: 2
     NumTransmitAntennas: 1

The showResourceMapping method shows the mapping of data, pilot, and null subcarriers in the time-frequency space. Apply the showResourceMapping method.

showResourceMapping(ofdmMod)

Input Arguments

ofdmmod — System object to visualize

comm.OFDMModulatorSystem object

OFDM modulator, specified as a comm.OFDMModulatorSystem object.

ci — Subcarrier indices to visualize

[1,…,NFFT] (default) | 1-by-2 integer row vector

Subcarrier indices to visualize, specified as a two-element row vector of integers. ci should satisfy diff(ci)= N_FFT − 1.