匹配干涉结构对远程光纤传感系统噪声的影响

Abstract

Objective The interferometric optical fiber sensing (OFS) system based on the beam interference principle has the advantages of a wide working frequency band, small volume, and invulnerability to electromagnetic interference. It is of great significance for national security, oil and natural gas exploration, seismic detection and warning, etc. The Mach -Zehnder and Michelson interferometer structures are commonly used in practical OFS systems. Among them, the OFS system with pathmatched differential interference (PMDI) is one of the research hotspots for its simple structure, high optical energy utilization rate, and flexible demodulation schemes. Up to now, the interference of the conventional PMDI structure is usually perfectly matched, and the compensation interferometer is located at the emitter or receiver end. This structure has the following problems when it is applied to the remotely interrogated OFS system : 1) the pickup noise