nrWaveformGenerator - 5G NR DL - retrieving the symbol-frequency grid information before iFFT and CP.

I'm using nrWaveformGenerator for 5G NR DL and able to generate the DL waveform.

I'd like to access the IQ data in the frequency grid for each ODFM symbol per antenna, i.e. before iFFT and CP.

Can you please provide any guideline how it can be made possible?

Thanks!

Answer 1

[Vanita]

Hi Haran,

I understand that you want to access the IQ data in the frequency grid before IFFT and CP, you can look for "pdschGrid" in the following example https://www.mathworks.com/help/5g/ug/nr-pdsch-throughput.html

Additionally, please leverage the source code of “nrWaveformGenerator” to understand the internally how 5g nr waveform is generated, by using the following command:

edit nrWaveformGenerator.m

I noticed that on line 189 OFDM Modulation is performed.

Another approach you could try is manually demodulating the signal using the MATLAB functions “nrOFDMDemodulate”. For more details, Please refer to the MATLAB R2025a documentation here:

https://www.mathworks.com/help/5g/ref/nrofdmdemodulate.html

Hope this works!