Interferometric sensor with a PGC-AD-DSM demodulation algorithm insensitive to phase modulation depth and light intensity disturbance.

An interferometric sensor with asymmetric division and a differential-self-multiplication phase-generated carrier (PGC-AD-DSM) demodulation algorithm based on fundamental frequency mixing is proposed and experimentally demonstrated. The effect of carrier modulation depth C on the demodulation result is eliminated via DSM. The influence of light intensity disturbance on the demodulation result is also eliminated by asymmetric division. In experiment, the proposed algorithm eliminates the influence of C on the demodulation result. The signal-to-noise and distortion ratio of the sensor with the proposed algorithm achieves a gain of 7.77 dB over the PGC-Arctan algorithm and 9.48 dB over the PGC-DCM algorithm.