针对调频非线性和快速傅里叶变换（FFT）精度不高的问题，基于等光频间隔重采样的调频连续波测距系统，采用相位差测频法测量了待测目标点的距离；对调频连续波激光测距原理进行分析和推导，并依靠该系统进行了测距稳定性和测距误差的分析实验。结果表明：在8.3～9.3 m测量范围内，相位差测频法的测距单点稳定性范围为50～95 μm，测得的距离与理论距离的残余误差不超过100 μm；所提算法比快速傅里叶变换具有更好的测距精确性和稳定性。

In view of the problems that the sampling nonlinearity and the low accuracy of the Fourier transform, a frequency estimation based on phase difference method to measure the distance of the target point is used based on the ranging system of frequency modulated continuous wave, which is based on the equispaced-phase resampling. The principle is analyzed and deduced. The stability of distance measurement and the error of distance measurement are analyzed based on the system. The research results show that the residual error of the measured distance with phase difference frequency measurement and the theoretical distance is not more than 100 μm and the stability of the single point range is between 50-95 μm in the range of 8.3-9.3 m. Compared with the fast Fourier transform, phase difference frequency measurement has better accuracy and stability in ranging.