The Research of Polarization Feedback Control System Based on Double Mach-Zehnder Interferometer
Polarization induced signal fading always has an influence up on the visibility of the interference stripe and the accuracy of system location in the distributed optical fiber oil &gas pipeline leak detection system. Base on distributed sensor system polarization characteristic, this paper analyses the visibility of the interference stripe with the changing of polarization. Designed a feedback control system based on double Mach-Zehnder is used to eliminate the input light polarization fading. This system can effectively suppress the polarization fading in fiber optical sensor, making interferometer fringe visibility tends to 1 and the equilibrium state of input light polarization always closes to the best input sate of interferometer.
Y. T. Wang et al., "The Research of Polarization Feedback Control System Based on Double Mach-Zehnder Interferometer", Advanced Materials Research, Vols. 308-310, pp. 1751-1754, 2011