Patent ID: 6134015
Filing Date: 2000-10-17
Classification: G01D

Abstract:
A method for processing signals output from a pathlength mismatched interferometric sensor array that produces phase shifts in sensors included in the array to indicate changes in a parameter being monitored, comprising the steps of:sampling the signal output from each sensor in the array to obtain for each sensor a first set of signal terms Q.sub.k =Q.sub.0 B.sub.k sin .phi..sub.k corresponding to the sine of the phase shift and a second set of signal terms I.sub.k =I.sub.0 B.sub.k cos .phi..sub.k corresponding to the cosine of the phase shift;calculating a first quantity DQ.sub.k =.vertline.(Q.sub.u(k)).sup.2 -(Q.sub.s(k)).sup.2 .vertline. and a second quantity DI.sub.k =.vertline.(I.sub.u(k)).sup.2 -(I.sub.s(k)).sup.2 .vertline. where u(k) and s(k) are parameters used to determine indices that select specific sampled signals and k is a running index of the set of consecutive samples of Q and I; ##EQU8## calculating the ratio R=Q.sub.N /I.sub.N.