.Enhancement of signal-noise-ratio in a distributed polarization mode coupling detection system[J].Optoelectronics Letters,2007,3(1):57-61 Enhancement of signal-noise-ratio in a distributed polarization mode coupling detection system JING Wen-cai LI Xiao-jingi LIU Kun XU Tian-hua ZHANG Yi-mo ZHANG Hong-xia JIA Da-gong PENG Gang-Ding [1]College of Precision Instrument ＆ Opto-electronics Engineering, Natioual Education ministry Key Laboratory of Optoelectronics Information and Technical Science, Tianjin University, Tianjin 300072, China [2]School of Electrical Engineering and Telecommunications, University of New South Wales, Australia Abstract:       A distributed polarization-mode coupling measurement system was designed and implemented using white light interferometry. It can be used for the measurement of polarization mode coupling in a high-birefringence fiber of up to 1 km. This system can be used in both fiber-optic sensors and optical fiber communications. Wavelet Transform was adopted in data processing to improve the signal-noise-ratio. The signal-noise-ratio of this system was improved more than 15 dB after denoising. The influence of denoising threshold on signal-noise-ratio and measurement accuracy was also discussed. Hilbert Transform and non-linear regression can be used in conjunction with Wavelet Transform to enhance the signal-noise-ratio and spatial resolution of this system. Hits: 3928 Download times: 206 View Full Text    Download reader