Generate complex noise samples from noise power (which is unknown) and known SNR.

I have generated complex signal samples using :

s = randn(3,4) + 1j*randn(3,4);

Then I want to generate a white noise as complex samples; then add them to the source signal (s). I have the SNR, and I want the generated signal to be based on the specified SNR; to get logic results in my simulation.

How can I create the white noise samples based on the SNR (I don't have Psignal and Pnoise, but I can assume one of the powers is known but don't know what values to assume)? I don't want to used awgn because it assumes 0dB as the power of the source signal.

Answer 1

[Santosh Fatale]

Hi Yara,

I understand that you want to generate complex noise signal and add it to original signal and that you know about SNR and you can assume signal/noise power.

I want to bring to your notice that in “awgn” function you can specify the signal power. The syntax is as follows:

y = awgn(x,snr,signalpower)

You can check out the awgn function link for more details.