基于联合定轨策略的星间相对测量自主定轨亏秩问题的改进

发展基于天基测控网的卫星测控定轨技术是克服传统地面测控方式缺陷的有效手段,而仅仅利用天基星间测量信息进行自主定轨易产生亏秩现象.为消除亏秩问题进一步提高定轨精度,本文以位置速度矢量作为轨道改进状态向量,对基于星间相对测量自主定轨亏秩问题的本质进行了再探讨,针对星间相对测量的三个应用领域中继卫星系统、编队卫星星座、双星定位系统提出了基于联合定轨策略的天地基测量信息融合的改进措施.以双星定位系统为例提出了数值融合联合定轨算法,并进行了联合定轨仿真实验.仿真计算结果表明,基于数值融合算法的联合定轨策略能够大大改善法方程系数矩阵的性态,两天观测数据下用户星定轨精度可以达到11.26米.

Improvement of Satellite-to-Satellite Relative Measurement Autonomous Orbit Determination Deficient-Rank Based on Combined Orbit Determination Strategy

Developing satellite tracking telemetry & command(TTC) and orbit determination technology based on space-based TTC network is an effective means which overcomes limitations of traditional ground TTC mode,but utilizing satellite-to-satellite measurement would arise deficient-rank.To eliminate deficient-rank and heighten orbit determination precision ulteriorly,this paper discusses the essence of satellite-to-satellite relative measurement based autonomous orbit determination deficient-rank by taking satellites position and velocity as orbit improvement state vectors,and puts forward space-ground-based measurement information fusion concrete improvement measures based on combined orbit determination strategy in the field of Tracking and Data Relay Satellite System(TDRSS),Formation Satellite Constellation(FSC) and Bi-satellite Positioning System(BPS).Then this paper brings forward numerical fusion combined orbit determination algorithm by taking precise orbit determination of BPS for example,and carried out simulation experiment.Simulation computation results show that the combined orbit determination strategy and its improved measures based on numerical fusion algorithm can ameliorate performance of B~TB greatly and user satellite orbit determination precision can reach 11.26 meters under two days observation data.