An Adaptive Demodulation Method for Extinction Ratio of Polarization Maintaining Optical Fiber

Abstract

The invention relates to a polarization maintaining optical fiber extinction-ratio self-adaptive demodulation method, which solves the polarization maintaining optical fiber extinction-ratio data demodulation problem. The polarization maintaining optical fiber extinction-ratio self-adaptive demodulation method comprises self-adaptive extinction-ratio threshold value coupling strength and converged non-uniform extinction-ratio iteration step. The demodulation comprises the steps of dynamically setting the extinction-ratio threshold value coupling strength according to the coupling situation inside an optical fiber to be measured, and realizing the self adaptability of the demodulation method; ensuring the iteration step to be dynamically changed and non-uniformly converged because the extinction-ratio iteration step depends on the previous iteration result and the iteration times, and realizing the quick demodulation of the polarization maintaining optical fiber extinction ratio; and detecting a weak coupled point inside the polarization maintaining optical fiber by adequately utilizing the characteristic that the white light interference precision is high and the dynamic range is large, and ensuring the demodulation result to be more precise and more reliable through the data preprocessing and self-adaptive extinction-ratio demodulation method.

Description

technical field [0001] The invention relates to the detection of distributed polarization coupling of polarization-maintaining optical fiber by white light interferometry, in particular to an adaptive demodulation method for extinction ratio of polarization-maintaining optical fiber based on distributed polarization coupling, and belongs to the technical field of optical measurement. Background technique [0002] High birefringence polarization-maintaining fiber is widely used in fiber optic gyroscope, fiber optic sensing, integrated optical information processing, optical communication, etc. and other fields. Extinction ratio is an important index to measure the polarization state stability performance of polarization maintaining fiber. Due to the influence of various internal and external disturbances such as internal stress defects, transverse stress, bending, twisting and other factors in the polarization maintaining fiber, its polarization extinction ratio is often low...

AI Technical Summary

Problems solved by technology

If a high-sensitivity photomultiplier tube is used for measurement, it is also necessary to effectively suppress the interference of stray light. At the same time, due to the influence of the extinction ratio of the polarizer, the theoretical test accuracy is limited to 60dB

The optical time domain reflectometry measures the power on the orthogonal axis of the backscattered light polarization separately, and calculates the extinction ratio. The experimental device is complicated and difficult to implement.

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