为了提高某GEO对地激光通信系统的可通率, 改善光学天线主镜、次镜的温度水平和温度不均匀性,对其遮光罩进行了优化设计。结合地球同步轨道外热流特点, 在不降低通信信号性能的前提下, 提出了内壁等间距排布栅板的遮光罩结构。首先, 以能量遮挡率不高于5%为约束条件, 讨论栅板、遮光罩内壁对主镜阳光辐射角系数的影响, 得出遮光罩优化设计方案;其次, 采用IDEAS软件开展系统热设计仿真分析, 考核栅板布局对主镜和次镜温度指标的影响; 最后, 计算采用优化后的遮光罩时的激光通信可通率。从温控的角度分析, 遮光罩内壁平行和垂直于赤道面方向都等间距布置4块栅板时, 与采用传统空心圆柱形遮光罩相比, 可通率从81.51%提高到91.21%。

In order to enhance the available probably ratio and to improve the temperature level and difference in a specific geostationary earth orbit (GEO) laser communication system, the structure of baffle was optimized. The baffle was uniformly installed grids on internal surface on the basis of GEO orbit external thermal flux characteristics, without the decrease of laser communication signal property. Firstly, the impact of grid and baffle inner wall on the solar view factor of the primary mirror was discussed in terms of energy shield ratio standard less than 5%. Then, the thermal simulation of temperature level and difference on the primary and secondary mirrors were performed by IDEAS, in which the influence of number and layout of grids on temperature indexes was analyzed. Finally, the laser communication available probably ratio with the optimized baffle was calculated. The results show that deploying 4 equally distributed grids along both parallel and vertical directions to the equator in the baffle, the available communication probably ratio is raised from 81.51% to 91.21% in comparison with the one of traditional cylindrical hollow baffle.