I am simulating a frequency division multiplexing of K channels.
The sources are random integers. The modulation is QPSK.
=What kind of lowpass filter shall I use?
=How shall I do the frequency shift (expj) in simulink? Should I do
it in frequency domain?
=Should the normalization be done in time domain?
=How shall I see the spectrum results? Is it done with spectrum
scope? I used it but it didn't work.
I have attached the figure.