导航卫星辐射光压建模进展及发展趋势

Research progress of radiation pressure modelling for navigation satellites

辐射光压模型是导航卫星精密定轨的研究热点之一。辐射光压的建模方法主要有经验方法、半经验方法和解析型方法。经验方法由于简单易用、无需知道卫星相关信息等特性而得到广泛应用。但是经验光压模型得到的卫星轨道质量还有进一步提高的空间。在辐射光压建模中引入更多航天器相关的信息可以弥补经验模型的缺陷。中国北斗卫星导航系统2020年建设完成并向全球提供服务,卫星的轨道精度是系统服务性能的重要指标。更好的辐射光压模型可提高北斗卫星轨道的质量。对辐射光压建模技术及研究进展进行梳理可为开发更精准的北斗卫星辐射光压模型铺路。首先根据辐射源的不同将辐射光压分为主动类型和被动类型。然后分析了经验模型、半经验模型以及分析型物理模型的优缺点。聚焦于北斗卫星,也梳理了北斗卫星辐射光压建模的研究进展。根据以上讨论分析了目前辐射光压建模研究未解决的问题。在北斗辐射光压建模中,建议联合解析模型和经验模型的优点,切勿在精密定轨中盲目估计经验参数。

Radiation pressure modelling has been a research focus in precise orbit determination of navigation satellites. In the development of radiation pressure modelling techniques, the analytical approach and the empirical approach have been used. The empirical approaches are used more widely than the analytical approach due to simplicity and less knowledge about the space vehicle needed in developing the models. However, the orbit derived from empirical models still have space to be improved. To bring in more information about the space vehicle in developing radiation pressure models is a way to tackle the flaws of empirical approaches. Specifically, China’s BeiDou system completed its constellation construction in 2020, and started providing services to global users. The orbit accuracy of BeiDou-3 satellites is an important factor for precision applications. Better radiation pressure models also contribute to improving orbit accuracy of BeiDou-3 satellites. A review of radiation pressure modelling for navigation satellites can pave the way for developing better modelling techniques. In this paper, radiation pressure is classified into “active” and “passive” cases according to whether the radiation flux is generated by the space vehicle surfaces. Then, the empirical models, semi-analytical models and analytical models are discussed in detail. The radiation pressure modelling approaches for BeiDou satellites are also reviewed. The unresolved problems in radiation pressure modelling are stated based on the above discussions. Considering both the limitations of analytical approaches and empirical approaches, we suggest that a combination of analytical approach and empirical approach could be a modelling strategy for BeiDou satellites and other navigation satellites. The empirical parameters should not be estimated blindly in precise orbit determination.