FIBER BRAGG GRATING SENSOR SYSTEM

摘要

PURPOSE: An optical FBG(Fiber Bragg Grating) sensor system is provided to increase a transmission distance by using a simple demodulation scheme without using a specific amplifier. CONSTITUTION: A reference FBG(500) reflects an optical modulation signal transmitted through a bi-directional transmission line(400) from a multiplexing unit(300) or pump light through the bi-directional transmission line. A sensor head FBG(600) reflects the optical modulation signal or the pump light of the reference FBG according to a sensing environment through the bi-directional transmission line. A light detecting unit(700) generates an electric bit signal by combining the reflected optical signals. [Reference numerals] (100) Light modulation unit; (200) Pump light output unit; (300) Multiplexing unit; (400) Bi-directional transmission line; (500) Reference FBG; (600) Sensor head FBG; (700) Light detecting unit; (750) Signal analysis unit;