捕获、对准、跟踪(APT)系统是空间激光通信重要组成部分，是通信正常进行的前提与保障。对APT系统组成原理、工作原理、关键技术、系统设计、工程实现等内容进行了详细的研究，在此基础上开展室内模拟实验及野外演示验证实验。室内模拟实验跟踪精度达到2~3 μrad，表明本系统可应用在星间激光通信中。野外双端动态演示实验在飞艇船舶间进行，结果表明系统捕获概率优于95%，捕获时间小于60 s，系统跟踪精度由于受到大气湍流影响而降低，多次实验测试表明在湍流中跟踪精度达到5~25 μrad。APT系统的成功研制为空间激光通信顺利进行奠定了基础。

Acquisition, pointing and tracking (APT) system is an important part in space laser communication, which is the premise and guarantee for normal work. The composition principle of system, operational principle, key technology, system design and engineering implementation are researched in detail. The simulation experiment indoor and dynamic experiment outdoor are carried out, respectively. The tracking precision in simulation experiment is 2~3 μrad, which proves this system can be used in inter-satellite laser communication. Dynamic demonstration experiment is achieved between airship and ship. The results prove that the acquisition probability is higher than 95%, and acquisition time is less than 60 s. Because of turbulence effect, tracking precision will decrease observably. The tracking precision in turbulence is 5~25 μrad, Development of APT system establishs the foundation for space laser communication execution successfully.