The polarization characteristics of the lithium niobate multifunction integrated optic circuit (MIOC), including its polarization extinction ratio (PER) and pigtail crosstalk, have a significant impact on the accuracy of fiber optic gyroscopes. A distributed polarization coupling (DPC) MIOC polarization parameter measurement method based on noise reduction processing is proposed. The proposed method aims to classify signal components decomposed by complete ensemble empirical decomposition with adaptive noise (CEEMDAN) by setting the threshold of the autocorrelation coefficient to filter out noise components. By setting the dynamic threshold and step size, DPC points are adaptively extracted from the denoised signal and superimposed to calculate the PER and pigtail crosstalk. Compared with empirical mode decomposition and ensemble empirical mode decomposition methods, the PER value obtained by the CEEMDAN method has the best consistency with the measured value of a commercial extinction ratio meter, the mean difference is 0.014 dB, and the pigtail crosstalk is −43.77 dB.

中文翻译：

---

基于降噪处理的Y波导多功能集成光路偏振特性参数测量

铌酸锂多功能集成光路（MIOC）的偏振特性，包括其偏振消光比（PER）和尾纤串扰，对光纤陀螺仪的精度有显着影响。提出一种基于降噪处理的分布式偏振耦合（DPC）MIOC偏振参数测量方法。该方法旨在通过设置自相关系数的阈值来滤除噪声分量，对自适应噪声完全系综经验分解（CEEMDAN）分解的信号分量进行分类。通过设置动态阈值和步长，从降噪信号中自适应提取DPC点并叠加以计算PER和尾纤串扰。与经验模态分解和集合经验模态分解方法相比，CEEMDAN方法得到的PER值与商用消光比计的测量值一致性最好，平均差为0.014 dB，尾纤串扰为-43.77 dB 。