A dual‐frequency continuous wave Doppler lidar for long‐distance and high‐precision velocity measurement is experimentally demonstrated in this article. The lidar system uses the optical heterodyne detection method to avoid complicated optical coherent configuration. All Phase Fast Fourier Transform and Chirp‐Z Transform are used to obtain the Doppler frequency shift. The maximum of the calculated Doppler shift was 999.83 Hz with the frequency resolution of 0.54 Hz, and the corresponding theoretical velocity was determined to be 749.87 m/s. During the experiment, the speed of the car was successfully measured in the outdoor environment, the frequency and velocity resolutions were less than 0.5 Hz and ± 0.2 m/s, respectively, and the detection distance of moving and stationary targets reached 1100 m and 2300 m. The capability of the dual‐frequency Doppler lidar system has been verified.

中文翻译：

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用于远距离速度测量的双频连续波多普勒激光雷达

本文通过实验证明了用于远距离和高精度速度测量的双频连续波多普勒激光雷达。激光雷达系统使用光学外差检测方法来避免复杂的光学相干配置。所有相位快速傅立叶变换和Chirp-Z变换都用于获得多普勒频移。计算出的多普勒频移的最大值为999.83 Hz，频率分辨率为0.54 Hz，相应的理论速度确定为749.87 m / s。在实验过程中，成功地在室外环境中测量了汽车的速度，频率和速度分辨率分别小于0.5 Hz和±0.2 m / s，移动目标和静止目标的检测距离分别为1100 m和2300米