Eliminating polarization-induced fading in interferometric fiber-optic arrays by modulation

摘要

This paper puts forward a new method to overcome the polarization-induced fading (PIF) in conventional low-birefringence optical fiber constructed interferometric sensor arrays. By inducing high frequency modulation to the state of polarization at the output end of the array, the maximum PIF variation of each sensor's signal is 4.7dB or 6.3dB according to the selection of modulation signal. Combined with an electronic automatic gain control circuit or dividing the each sensor's signal by its visibility, each sensor's signal fading is recovered at the expense of a relevant signal/noise ratio degradation of 4.7dB or 6.3dB.