Gaussian noise generation

Question

I want to generate Gaussian noise in GNU Radio companion.I have studied that by feeding a VCO with a saw tooth wave can do that.Can any body explain how the signal from the VCO will have a Gaussian distribution? As i think it will have a uniform distribution because the frequency is first increased and the decreased and all the frequencies will have equal probability of occurrence. Regards, Ali

Answer 1

The easiest way would be to use the channel model blocks available in recent GNU Radio releases. There's information on this page: http://gnuradio.org/doc/doxygen/page_channels.html

For simple Additive White Gaussian Noise (AWGN), simply set the noise voltage and ignore the other parameters (which are useful for emulating a more realistic channel, but are not related to your immediate question). Bear in mind that you are adding noise, so the number you use for noise voltage is specifying the 'noise floor', as opposed to specifying eg the desired SNR.