GEO激光通信光端机遮光罩优化设计

Design of Optimization-Baffle for GEO Laser Communication

地球同步卫星(GEO)激光通信系统的光学天线暴露在卫星外部,太阳辐射会对光学天线产生严重的影响,造成可通率下降,尤其阳光直接照射天线主镜时系统必须采取规避措施,影响更加严重。采用遮光罩可以改善太阳热效应对光学天线的影响,但受尺寸等限制,其效果有限。根据GEO对地激光通信系统的结构和环境特点,分析太阳对光学天线主镜的辐照情况,设计一种在传统圆筒遮光罩内部增加栅板的改进型遮光罩,减小太阳光的直射角度范围。结合热控设计,对系统在太阳辐照环境下天线光学元件的温度变化情况及可通率进行仿真分析。分析表明采用改进型遮光罩后,系统的可通率由采用传统遮光罩时的93%提高到99.5%,基本达到全天时工作,极大地减小了系统的不可通时间,提高了链路的可用性。

The optical antenna of geosynchronous earth orbit（GEO） laser communication system exposes outside of satellite. Solar radiation affects the optical system seriously, and reduces available probability.The effect is more serious when the sun directly shine the primary mirror. The baffle can reduce the effect, but it is limited by the fairing′s size of rocket. By researching the characteristics of the GEO laser communication and analyzing the situation of primary mirror shined by the sun, a modified baffle with internal grids is designed to reduce the effect of the sun. Then the optical-device′s temperature and the available probability of the system combined the thermal control design are analysed. The results show that the available probability is improved from 93% with traditional baffle to 99.5% with the improved baffle. The GEO laser communication system can almost work all day with the modified baffle.