在大气激光通信中捕获对准跟踪(APT)是通信成功的前提。对空间激光通信中的捕获对准跟踪系统常用的两种光束定位探测器件CCD和四象限光电探测器(QD)的特性进行了深入分析,研究了影响大气激光通信跟踪系统性能的5种大气湍流效应,分别讨论了光束漂移、光强起伏、光斑弥散、到达角起伏及光束扩展的原理及对应仿真结果。结合大气湍流和探测器,针对质心跟踪算法和形心跟踪算法进行深入分析,得到并实验验证了在大气条件下形心算法的跟踪误差小于质心误差的结论。 Acquiring alignment tracking (APT) in atmospheric laser communications is a prerequisite for successful communications. In this paper, the characteristics of two commonly used CCD camera and four-quadrant photodetector (QD) in the acquisition and tracking system for space laser communication are analyzed in detail. Five kinds of atmospheric turbulence affecting the performance of atmospheric laser communication and tracking system are studied. Effects, respectively, discussed the beam drift, light intensity fluctuations, spot dispersion, arrival angle fluctuations and the expansion of the beam principle and the corresponding simulation results. Combining the atmospheric turbulence and the detector, the centroid tracking algorithm and the centroid tracking algorithm are deeply analyzed. The results show that the tracking error of the centroid algorithm is less than the centroid error under atmospheric conditions.