Editing Rayleigh fading (section)

===Filtered white noise===
Another way to generate a signal with the required Doppler power spectrum is to pass a [[white noise|white]] Gaussian [[signal noise|noise]] signal through a Gaussian filter with a frequency response equal to the square-root of the Doppler spectrum required. Although simpler than the models above, and non-deterministic, it presents some implementation questions related to needing high-order filters to approximate the irrational square-root function in the response and sampling the Gaussian waveform at an appropriate rate.