单频激光干涉仪正交信号的高精度处理

为了提高单频激光干涉仪正交信号相位细分辨向的可靠性与重复性,本文在正交信号Heydemann误差模型和数字信号处理技术的基础上,提出一种结合误差修正和相位细分辨向技术的正交信号高精度误差补偿算法。该算法采用基于最小二乘法的矩阵运算计算正交误差补偿参数初值,通过迭代运算进一步提高补偿精度,并对修正后的信号构建了基于相位的细分辨向算法。最后通过MATLAB软件对该算法进行了验证。实验结果表明,上述算法可实现对正交信号误差的精确补偿,使测量精度可达亚纳米甚至皮米数量级,从而有效提高测量信号的解调精度。

High precision processing of quadrature signals for homodyne interferometer

In order to improve the reliability and repeatability of phase counting and subdivision of quadrature signals for homodyne interferometers ,a high accuracy error compensation algorithm for quadrature signals combined error correction with phase-based counting and subdivision was proposed based on the Heydemann correction model of quadrature signals and digital signal processing technology . Matrix manipulation based on the least square method was adopted to calculate compensation parameter initials of quadrature signals ,which were corrected by iterative operation to further improve the compensation accuracy .Then phase-based counting and subdivision algorithm was established base on the revised signals .Finally ,the algorithm was verified with Matlab software . Experimental results show that the proposed algorithm can accurately compensate the error of the quadrature signals ,and the measurement accuracy achieves sub-nanometer or even picometer scales , thus the demodulation accuracy of the measured signals can be improved effectively .