全天时星敏感器的建模分析与实验验证

Modeling analysis and experimental verification for all-time star sensor

全天时星敏感器技术可以将星敏感器的应用推广到临近空间飞行器如平流层飞艇和高空气球等平台,是星敏感器未来发展的一个重要方向。由于白天受到强烈的大气背景辐射的影响,可见光波段星敏感器的探测能力显著受限。大气背景辐射在短波红外处的强度迅速降低,因此利用短波红外成像系统在0.9~1.7μm波段下进行恒星探测成为研究全天时星敏感器技术的一种有效可行的方案。为了系统地分析并验证短波红外全天时星敏感器的可行性,文中在分析全天时星敏感器探测模型的基础上,重点讨论了短波红外探测器噪声对星敏感器探测能力的影响并基于探测模型确定了20 km高度处全天时星敏感器的光学参数。基于短波红外探测器研制了全天时星敏感器原理样机,结合地面处的观星实验,测试了原理样机的探测性能并验证了全天时星敏感器探测模型的正确性。

As an important direction for the future development of star sensors,all-time star sensor technology can extend the application of star sensors to near space platforms such as stratospheric airships and high-altitude balloons.Due to the intense atmospheric background radiation during daytime,the detection capability of star sensors in visible band was significantly limited.The intensity of atmospheric background radiation in the short-wave infrared(SWIR)band was rapidly reduced compared to that in the visible detection band.Therefore,the application of SWIR imaging systems for star detection in the range of 0.9-1.7μm has become an effective solution for studying the all-time star sensor technology.In order to analyze and verify the feasibility of SWIR all-time star sensor,the all-time star sensor detection model was analyzed and the impact of SWIR detector noise on the detection capability was discussed in this paper.Then,the optical parameters of the all-time star sensor at a height of 20 km were determined through simulation calculation.The prototype of the all-time star sensor was developed based on SWIR detector.Combined with the star observation experiments at the ground,the detection performance of the prototype was tested and the correctness of the all-time sensor detection model was verified.