相位敏感型光时域反射仪（ФOTDR）在周界安防，地震波监测、石油勘探等领域具有广阔应用前景。近年来，随着ФOTDR系统向远程、高检测灵敏度的相位探测方向进一步发展，相位噪声已成为制约系统探测性能的关键因素。本项目针对ФOTDR系统中相位噪声问题开展研究，旨在： 1) 建立激光器噪声向ФOTDR系统相位噪声转化的理论模型，阐述该噪声转化过程的物理机制；2) 研究ФOTDR系统中MI动态特性，建立理论模型分析MI对ФOTDR系统相位噪声的影响机制；3) 研究感应MI与自发MI的竞争关系，利用感应MI的竞争优势抑制自发MI导致的ФOTDR系统相位噪声；4)对远程高灵敏度ФOTDR系统相位噪声进行综合研究，有效提升ФOTDR系统性能。本研究对ФOTDR系统向远程高检测灵敏度方向发展提供理论基础和关键技术支撑。

Phase sensitive optical time domain reflectometer (ФOTDR) has great potential in the fields of intrusion detection, seismic wave detection and oil exploration. Recent years, with the development of the ФOTDR in the direction of long distance and high detecting sensitivity，phase noise in the system has been the key factor to limit the performance. The project focuses on the phase noise in the ФOTDR system. Firstly, a comprehensive model is established to describe the mechanism that laser noise converts into the phase noise of ФOTDR; Secondly, The MI dynamics is studied in the ФOTDR, and a theoretical model is established to analyze the effect of MI on the phase noise in ФOTDR; Thirdly, The competition between induced MI and spontaneous MI is studied, based on which a method is proposed to suppress the MI induced phase noise in ФOTDR; Finally, the phase noise in remote high detecting sensitivity ФOTDR system is studied comprehensively to promote the performance.The project has important meaning for the development of ФOTDR in the direction of long distance and high detecting sensitivity.