【摘要】 为了克服伴生调幅对光源调频型相位生成载波(PGC)解调方法的影响,提出一种基于双路干涉信号和微分-交叉相乘(DCM,differential-cross multiply)的PGC解调方法。通过3×2耦合器引入双路干涉信号,直接调制光源频率获得相位载波。实验结果表明,新方法较好地消除了光源伴生调幅的影响。对于4 rad的解调信号,总谐波比提高20 dB以上,幅值偏差为0.08 rad,而单路干涉信号的DCM-PGC方法的偏差达0.33 rad。并且,新方法的信噪比和信纳比均有显著的改善。更多还原

【Abstract】 In order to eliminate the effect of amplitude modulation in the source with direct frequency modulation(DFM) on phase generated carrier(PGC) demodulation approach,a new PGC method was proposed based on differential-cross multiply(DCM) and double interferometric signals by a 3×2 directional coupler.Experimental results confirm that the new scheme has eliminated the effect of the companion amplitude modulation on demodulation very well.For a demodulation signal of 4 rad,the total signal-harmonic-ratio(SHR) increases by more than 20 dB,and the amplitude deviation of this new method is 0.08 rad,while it is up to 0.33 rad by the DCM-PGC approach for a single interferometric signal.Besides,the signal-tonoise ratio(SNR) and signal-to-noise-and-distortion(SINAD) are also improved significantly.更多还原