无信标星间激光通信系统粗精复合扫描方法

无信标星间激光通信系统无需额外设置信标光组件，直接采用小束散角的信号光进行瞄准捕获跟踪，有利于降低终端的质量、体积、功耗和制造成本等重要指标，满足商业航天和低轨卫星空间激光网络的发展要求。为了克服现有无信标激光通信系统扫描时间长、捕获难度大的问题，综合考虑星上姿态变化、测量精度和终端安装定位误差等因素，对扫描不确定域进行了数值计算，设计了无信标扫描捕获流程，定量分析了粗精扫描机构控制带宽、扫描步长、规划路径与光束覆盖面积的耦合关系，提出了一种简单可靠的无信标粗精复合螺旋扫描方法。典型环境仿真结果表明，采用所提方法平均扫描捕获时长小于20 s，捕获概率大于95%，有效提升了无信标系统的扫描效率，可满足未来低轨卫星空间激光网络的快速建链要求。

Coarse-refined combined scanning method of beaconless inter-satellite laser communication system

The beaconless inter-satellite laser communication system (BILCS) does not to configure beacon light components, and directly applies signal light with small divergence angle to pointing, acquisition and tracking (PAT), which is beneficial to reduce the weight, volume, power consumption and manufacturing cost of the terminal, and meet the development requirements of commercial spaceflight and LEO satellite space laser network. To overcome the existing shortcomings of long scanning time and difficult acquisition of BILCS, satellite attitude change, measurement accuracy and terminal positioning error were taken into consideration, the scanning field of uncertainty was numerically computed, the beaconless scanning-acquisition process was designed, the coupling relationship of the control bandwidth of the coarse and refined scanning mechanism, scanning step size, planning path and the light coverage area was quantitatively analyzed, a simple and reliable coarse-refined combined spiral scanning method based on beaconless was proposed. Simulation results of typical environment demonstrate that the average acquisition time is less than 20 s, and the acquisition probability is more than 95% by this method, which effectively improves the BILCS scanning efficiency, and can satisfy the requirements of the future LEO satellite space laser network to rapidly establish laser communication link.