一种提高相位测距精度的方法

摘要

In laser phase ranging,the distance is obtained though the phase of echo signal. Because of spectrum leakage and fence effect,the traditional FFT cannot calculate the phase accurately. Therefore,using frequency spectrum refinement and correction technology to estimate the phase of echo signal is proposed in this paper. Theoretical analyses and experimental results demonstrate that the computing amount of multiple modulation zoom spectrum analysis based on complex analytic band-pass filter is small and the computing speed is quick, while the correction accuracy is the highest. Resolution of frequency spectrum can be improved by frequency spectrum refinement and correction technology , which is very useful in laser phase ranging. The technology in this paper can greatly improve the accuracy of laser ranging in engineering application.%在激光相位测距中,距离是通过求回波信号的相位信息求得的.由于频谱泄露和栅栏效应,传统的FFT不能精确地计算出频率点的相位值,因此提出使用密集频谱细化技术和频谱校正技术对回波信号的频谱进行校正.实验结果表明:基于复解析带通滤波器的复调制谱细化算法所需的运算量少,计算速度快,同时能够提高相位测量精度;频谱校正算法中相位差校正算法是一种精确的校正方式,校正精度很高;频谱细化和频谱校正技术大大提高了频谱分辨率.在工程应用中,本文方法运用于激光相位测距中能大幅度提高频域数字测相的精度.