DISTRIBUTED VIBRATION SENSING SYSTEM USING MULTIMODE FIBER
摘要
An optical time domain reflectometry (OTDR) system is configured to detect Rayleigh backscatter reflected from a multimode sensing optical fiber. The system includes a single spatial mode filtering system to select a single speckle of the Rayleigh backscatter produced in response to an optical pulse launched into the multimode fiber. The detected single speckle may be used for distributed disturbance (vibration) detection.