基于卡尔曼滤波的PGC解调非线性误差补偿方法  

Nonlinear Error Compensation Method for PGC Demodulation Based on Kalman Filtering

作　　者：严利平[1] 周春宇 谢建东[1] 陈本永[1] 楼盈天[1] 杨涛[1] Yan Liping;Zhou Chunyu;Xie Jiandong;Chen Benyong;Lou Yingtian;Yang Tao(Nanometer Measurement Laboratory,Zhejiang Sci-Tech University,Hangzhou,Zhejiang310018,China)

机构地区：[1]浙江理工大学纳米测量技术实验室,浙江杭州310018

出　　处：《中国激光》2020年第9期134-141,共8页Chinese Journal of Lasers

基　　金：国家自然科学基金(51875530,51527807);浙江省自然科学基金(LZ18E05003,2017R51006);教育部长江学者和创新团队计划(IRT_17R98)。

摘　　要：针对载波相位延迟和调制深度漂移对正弦相位调制干涉仪中相位解调精度的影响,提出一种基于卡尔曼滤波的相位生成载波(PGC)解调非线性误差补偿方法。首先建立由PGC正交分量参数构成的卡尔曼滤波状态空间观测模型。然后对PGC解调的正交分量幅值和偏置进行最优估计与修正,减小相位解调的非线性误差。最后理论分析阐述该补偿方法的原理,开展模拟干涉信号的相位解调仿真测试和正弦相位调制干涉位移测量实验。实验结果表明:提出的方法能够有效减小PGC相位解调非线性误差,实现纳米级精度的位移测量。To determine the influence of carrier phase delay and modulation depth drift on the accuracy of phase demodulation in sinusoidal phase modulation interferometers, a phase-generated carrier(PGC) demodulation nonlinear error compensation method based on a Kalman filter is proposed. First, we establish a Kalman filter state space observation model composed of PGC orthogonal component parameters. Next, the amplitude and offset of the orthogonal components of the PGC demodulation are optimally estimated and corrected to reduce the nonlinear error of the phase demodulation. Finally, a theoretical analysis is conducted and used to explain the principle of the compensation method, and we carry out the phase demodulation simulation test of an analog interference signal and a sinusoidal phase modulation interference displacement measurement experiment. The experimental results show that the proposed method can effectively reduce the nonlinear error of PGC phase demodulation and facilitate displacement measurement with nanometer precision.

关 键 词：测量 正弦相位调制干涉仪 相位生成载波 非线性误差 卡尔曼滤波 

分 类 号：TH741[机械工程—光学工程]