光通信技术2026，Vol.50Issue(4)：39-44,6.DOI:10.13921/j.cnki.issn1002-5561.2026.04.006
Φ-OTDR外差相干探测解调方法性能比较
Comparison of demodulation methods for Φ-OTDR heterodyne coherent detection
摘要
Abstract
Aiming at the selection of demodulation methods for heterodyne coherent detection in phase-sensitive optical time-domain reflectometer(Φ-OTDR)systems,a Rayleigh backscattering and disturbance signal model is constructed with balanced photodetector noise incorporated.The performances of IQ demodulation and Hilbert demodulation are systematically com-pared in terms of signal-to-noise ratio,disturbance waveform,disturbance frequency,and detection distance.Experimental re-sults show that both methods can achieve distortion-free demodulation when SNR≥35 dB,when SNR<35 dB,IQ demodula-tion exhibits better noise immunity.Under different disturbance waveforms,IQ demodulation achieves lower distortion and bet-ter stability.Both methods can stably demodulate disturbances in the frequency range of 200～2 000 Hz.Under fixed system pa-rameters,the maximum effective detection distance of IQ demodulation reaches 12.7 km,which is approximately 53.01%lon-ger than that of Hilbert demodulation.关键词
光纤传感/相位敏感光时域反射仪/同相/正交解调/Hilbert解调/外差相干探测Key words
optical fiber sensing/phase-sensitive optical time domain reflectometry/in-phase/quadrature demodulation/Hil-bert demodulation/heterodyne coherent detection分类
信息技术与安全科学引用本文复制引用
赵丽娟,刘子义,黄梓朦,徐志钮,马家骏,代泽荟,李冠良..Φ-OTDR外差相干探测解调方法性能比较[J].光通信技术,2026,50(4):39-44,6.基金项目
国家自然科学基金项目(62171185、62273146)资助 （62171185、62273146）
河北省省级科技计划资助项目(SZX2020034)资助. （SZX2020034）
