使用窄线宽半导体激光器、声光移频器、马赫-曾德尔幅度调制器以及全光纤相干光路,构建了一套基于平衡相干探测与啁啾调幅的激光测距实验系统。介绍了啁啾调幅相干激光雷达的工作原理,完成了基于直接数字合成(DDS)技术的啁啾信号生成及射频信号处理电路的设计。对实验系统的时间分辨力与最小可探测功率进行了测试,对实验出现的一些现象进行了分析。 A laser ranging system based on balanced coherent detection and chirp amplitude modulation is constructed using a narrow-linewidth semiconductor laser, an acousto-optic frequency shifter, a Mach-Zehnder amplitude modulator, and an all-fiber coherent optical path. The working principle of chirp AM coherent laser radar is introduced. The design of chirp signal generation and RF signal processing circuit based on direct digital synthesis (DDS) is completed. The time resolution of the experimental system and the minimum detectable power were tested, and some phenomena appeared in the experiment were analyzed.