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System object: comm.OFDMDemodulator
Package: comm

Provide dimensioning information for the OFDM method


Y = info(H)


Y = info(H) provides data dimensioning information for the OFDM demodulator System object™, H. It returns the expected dimensions for data input into the OFDM demodulator, for the pilot output, and for the data output from the demodulator. The output, Y, is a structure containing three fields: InputSize, DataOutputSize, and PilotOutputSize.


Gives the dimensions of the demodulator input data, [(NFFT + NCP) × Nsym]-by-Nr, where NFFT is the number of subcarriers, NCP is the length of the cyclic prefix, Nsym is the number of symbols, and Nr is the number of receive antennas.


Shows the dimensions of the demodulator output data, Ndata-by-Nsym-by-Nr, where Ndata is the number of data subcarriers such that Ndata = NFFT − NleftG − NrightG − NDCNull − Npilot − NcustNull. The variables are defined as follows:

NFFTNumber of subcarriers
NleftGNumber of subcarriers in the left guard band
NrightGNumber of subcarriers in the right guard band
NDCNullNumber of subcarriers in the DC null (either 0 or 1)
NpilotNumber of pilot subcarriers
NcustNullNumber of subcarriers used for custom nulls

Provides the dimensions of the pilot signal output array, Npilot-by-Nsym-by-Nr or Npilot-by-Nsym-by-Nt-by-Nr, depending on the number of transmit antennas.