卫星激光通信的核心技术是PAT技术,即瞄准、捕获、跟踪技术,而实现微弧度量级的跟瞄技术是其中的关键点和难点。通信端机研制完成后,需要对其各种胜能指标进行测试,跟瞄精度是其中的一项重要指标。按照一般测试原则,跟瞄精度测试装置的精度应达到亚微弧度,并达到几百赫兹的带宽。基于点光源、长焦距透镜、PZT器件、平面反射镜及4QD光电器件等,设计并研制了一套能完成通信端机跟瞄精度测试的装置。给出了测试的基本原理、测试方法、测试装置的结构以及元件参数设计,并推导了椭圆光斑时光斑质心定位算法。实验数据表明,所研制的测试装置可以达到3σ=0.37urad(100mm孔径)的测试精度以及优于250Hz的带宽。
A tracking and pointing measuring device is proposed based on point source,long focal lens,PZT,flat reflector and 4 QD,which satisfies the measurement requirement in free space laser communication. The principle, measuring method, structure and parameters of the device are given and the centroidal calculating formula of elliptical spot is derived. Experi- mental results proved that the accuracy of the measuring device is 3σ 0.37 urad (100 mm aperture) and its band width is more than 250 Ha