提高卫星光通信扫描捕获概率的方法研究

在相同的外部环境和系统参数条件下，捕获扫描方式的选择直接影响卫星间光通信终端的捕获性能。粗瞄误差是确定捕获扫描方案过程中的首要考虑因素，通常假设为水平俯仰对称高斯分布，这时螺旋扫描为最佳扫描方式。在实际卫星平台姿态控制过程中，姿态误差在各个转动轴方向上的分布一般是不对称的，进而造成粗瞄误差分布的不对称，仍采用螺旋方式扫描可能效率较低。因此，通过理论分析和Monte Carlo仿真重新分析了捕获扫描方式的选择问题，提出了针对具体星上环境条件采用不同扫描方式的新结论。在卫星光通信的链路建立过程中，粗瞄误差不对称度较高时，同样的扫描时间限制内分行扫描可以获得更高的捕获概率。

Methods of Improving Acquisition Probability of Scanning in Intersatellite Optical Communications

Selections of acquisition scan methods decide the acquisition performance of a terminal in intersatellite optical communications under the same external conditions and system parameters.The coarse pointing errors are considered as the main factor in the design of the acquisition scan scenario.They are usually assumed to be identically distributed Gaussian random variables in the elevation and azimuth,so the spiral scanning is the best way for the acquisition.Errors in the rotational axes are not identically distributed during the actual control of the satellite pose,which causes coarse pointing errors to be with dissymmetrical distribution.So the spiral scanning may not be the best way.Selections of acquisition scan methods were studied again in this paper with the theoretical analysis and Monte Carlo simulation,and some new conclusions of the acquisition scan methods selection were drawn according to the different satellite conditions.Giving the same limit for the acquisition time,a larger acquisition probability is obtained with the raster scanning during the link foundation when the coarse pointing errors asymmetry is high.