Representation and measurement of nonlinearities in stimulus signals

In this paper we present a simple and cost effective yet accurate setup for measuring the amplitude distribution of a signal and its probability density function (pdf). From these it will be shown how to measure linear and nonlinear errors through a third order Taylor series representation of the distorted signal. We also show how this representation of the nonlinear behavior of the signal could be used as an horizontal metric for adequacy of the amplitude distribution in the histogram method. Finally, experimental results concerning the characterization of two sine wave generators are presented and compared with measurements made with a spectrum analyzer.