An improved PGC demodulation algorithm based on a reference interferometer to reduce intensity and phase noise

Abstract In this paper, an improved algorithm based on the reference interferometer for noise reduction is proposed. The method uses a reference interferometer to suppress the phase noise, followed by the Arctan algorithm to further reduce the intensity noise of the system. Meanwhile, it also eliminates the effects of light intensity disturbances. The results of the simulation and experiment are consistent with the theoretical analysis. Experimental results show that the noise reduction effect of the improved algorithm based on the reference interferometer is significantly improved in the 0–2 kHz frequency band. At 1 kHz, SNR is about 15 dB higher than the traditional PGC-DCM algorithm, and about 12 dB higher than the PGC-DCM algorithm based on the reference interferometer.