GNSS无线电掩星大气探测混合星座设计

针对目前GNSS无线电掩星大气探测卫星星座参数依赖大量仿真计算进行统计选取的研究现状,通过将探测卫星星下点与大气测点间地心角距作为观测半径提出了一种虚拟“星—地”遥感假设,给出了一种崭新的掩星测点预估方法,具有计算速度快的特点.基于该方法推导了探测星座参数与大气探测覆盖性之间的极值相关特性,建立了GNSS无线电掩星大气探测卫星星座设计准则,并以GPS和BD为兼容性观测信源完成了GNSS掩星大气探测混合卫星星座设计.通过仿真试验,验证了设计方法的快速性和可行性,GPS+BD掩星大气探测混合星座每日可实现掩星探测量为COSMIC星座的3倍以上,12h内掩星测点全球分布均匀度提升12％.

Research on the Multi-Constellation Design for GNSS RO Atmosphere Sounding

The radio occultation (RO) atmospheric sounding with global navigation satellite system (GNSS) has extended a new area on LEO satellite constellation application in the last decade, while the constellation designs so far are majorly dependent on a mass of simulations and statistical results.With the assumption of the "satellite-to-earth" remote sensing which takes the geocentric angle between sub-satellite point and the sounding point as the sensing radius, a novel estimates method for GNSS RO soundings to accelerate the constellation design.Based on this method, the related features between constellation parameter and sounding coverage are derived;the design criteria of GNSS RO constellation for atmospheric sounding are established, and a GPS+BD RO constellation is designed with Sun-synchronous orbit and low-inclination orbit.The simulation results shows that the constellation design method proposed in this paper is feasible and effective, the amount of soundings by the multi-constellation designed in this paper is tripled of COSMIC, and the uniformity of the sounding coverage in12h is improve by 12%