Rapid evaluation of the auto-correlation function of the output of single-valued non-linearities in response to sinusoidal and Gaussian signals

A method is presented which can be used for the rapid evaluation of the response of a single-valued non-linear element to a sinusoidal signal and Gaussian noise, applied separately or together. The technique used is to approximate the non-linear characteristic by a stepped or `digitized¿ waveform; exact evaluation of the response of the digitized characteristic can easily be obtained. A comparison of the results of the method with theoretical results for analytically defined non-linear characteristics shows good agreement.