两行根数辅助的SLR单站定轨

单站测距资料定轨的困难限制了漫反射SLR(Satellite Laser Ranging)测距资料的应用.为此,提出利用两行根数模拟多站SLR测距资料作为辅助,实现单站SLR测距资料定轨的方法.该方法对卫星Ajisai单站SLR测距资料定轨并生成5 d预报轨道,误差小于40 m,实现利用单站测距资料的轨道改进,验证了方法的可行性.

Two Line Element Aided Orbit Determination Using Single Station SLR Data

It is difficult to use the single-station satellite laser ranging(SLR) data for orbit determination,due to the singular geometrical distribution of the observations.The single-station data generated by performing diffuse-reflection SLR to the orbital space debris are therefore ineffective for orbit improvement. We propose a method to resolve the singularity in the observation distribution.Since the initial orbits of space debris such as the two line elements(TLE) exist prior to the SLR tracking,we use it to simulate observations from other SLR sites.We combine the simulated and actual observations with a proper weight to fit an orbit,thus resolving the singularity in the observation distribution.We then propagate the fitted orbit forward in time to validate against the precision ephemeris derived from the international laser ranging service(ILRS). The method is implemented and applied to the satellite Ajisai.Using the single-station SLR data of five passes in one day and corresponding TLE as the initial orbit,we fit the orbit and the generated predictions.The predicted position error is less than 40 meter in five-day span,significantly improved over the initial SGP4 propagated orbit.The method’s potential application to space debris orbit improvement is also discussed.