Patent ID: 6292760
Filing Date: 2001-09-18
Classification: G01R

Abstract:
A method of measuring a pseudo-coherent electrical signal having one or more sine and/or cosine components at n known signal frequencies Ft.sub.1, Ft.sub.2, . . . Ft.sub.n, comprising the steps of:providing a digitized signal corresponding to said pseudo-coherent electrical signal,selecting a set of n correlation frequencies Fc.sub.1, Fc.sub.2, . . . Fc.sub.n, said correlation frequencies being substantially close to said signal frequencies Ft.sub.1, Ft.sub.2, . . . Ft.sub.n ;computing a correlation matrix A of discrete time correlations between sampled unit amplitude sine and cosine waveforms at each of said correlation frequencies and sampled unit amplitude sine and cosine waveforms at each of said signal frequencies;computing the inverse of said correlation matrix, said inverse matrix represented by the notation A.sup.-1 ;computing a matrix B of discrete time correlations between sampled unit amplitude sine and cosine waveforms at each of said correlation frequencies and said digitized signal,multiplication of A.sup.-1 by B to produce a matrix C of sine and cosine amplitudes of said known frequencies of said pseudo-coherent signal.