Stroboscopic Real-Time Correlation Methods

Abstract

A new method, similar to the stroboscopic observation, for performing real-time auto-and cross-correlation of periodic signals is presented. Waveforms of auto-and cross-correlation functions are given in a magnified scale of time, by beat waveforms of two pertinent periodic signals. The method can be applied to signals expressed by periodic functions which are described as Fourier series. As an example, impulse responses of number of known electronic filters were recorded by a pen writing oscillograph using signals of m-sequences as the periodic test-signals in the stroboscopic correlation method. From these results, errors were estimated which resulted from the shape of the autocorrelation functions of signals of m-sequences. The method was proved to be useful for determining impulse responses of linear systems.