卫星激光通信终端光跟踪检测的数理基础

卫星激光通信光束的传播在空间属于远场衍射,而在地面光学跟踪检验中属于近场衍射。采用菲涅耳衍射理论研究了远场衍射和近场衍射对于产生光学跟踪位置误差信号的本质上的差别并且分析了等效条件,证明了近场检验中采用卫星相对角度运动轨迹的光束扫描可以准确模拟远场相对运动,同时也得到了光斑特性和卫星抖动模拟的分析。澄清了卫星激光通信终端光学跟踪性能检验中的基本概念,具有实际指导意义。

Mathematical and Physical Basis for Pointing, Acquisition and Tracking Testing of Inter-Satellite Laser Communication Terminals

The propagation of laser beam for inter-satellite laser communications belongs to the far-field diffraction,but the optical testing and verification in the laboratory is on the condition of the near-field diffraction.In terms of the Fresnel diffraction theory,the inherent difference on the optical tracking position errors between the far-field and near-field effects is studied,their equivalent conditions are analyzed.And it is found that the use of beam scanning in the near-field testing can accurataly simulate the mutual movement of satellites in the far-field and the trajectory formula for beam scanning is deduced.Investigation on the characteristics of focused spot and the effect from satellite vibration is presented.The results clarify the basic concepts necessary for the testing of optical tracking performance of inter-satellite laser communication terminals,which would provide helps in the ground testing.