Experiment set up for RIM-FDS with single mode illumination

To overcome the shortcoming of low sensitivity in RIM-FOS with LED illuminating, a theoretical model was introduced and an experiment system was designed using LD coupling with single mode fiber as illumination purpose. The system is made up with LD module, optic module, PIN detection module, signal collection module, FPGA module, up computer system and power module. The validation of model was proved by experiment results and the performance of RIM-FOS was presented. Experimental results indicate a sensitivity of 3.15 mV/m and linear region of 380 m for front slope, a sensitivity of 0.76 mV/m and linear region of 690 m for back slope of RIM-FOS. Good stability and repetition are proved for system, and the system will play a significant effect for the further study of RIM-FOS with single mode illumination.