Phase-generating carrier interrogator and related phase-generating carrier interrogation method - Patent Application 20070122997

Abstract

A phase-generating carrier interrogator is disclosed. The phase-generating carrier interrogator includes one or more interferometers operable to receive modulated radiation and to generate respective interferometer signals including a target phase induced by a measurement target. Each interferometer signal also includes a periodic phase modulation induced by the modulated radiation. The periodic phase modulation has an amplitude described by a respective modulation index of each interferometer. The phase-generating carrier interrogator also includes at least one detector operable to detect each interferometer signal, and a signal processing module operable to estimate a respective modulation index for each interferometer, obtain a respective estimated modulation index for each interferometer, demodulate each interferometer signal using the respective estimated modulation index, and estimate a respective target phase from the respective interferometer signal, thereby obtaining a respective estimate of the target phase for each interferometer.

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