日地L2点航天器编队的分布式自主相对导航

为了实现航天器编队在日地L2点轨道的高精度相对导航，设计了一种分布式的自主导航方法。首先通过信息交互形成局部的测量构型，每颗卫星只基于邻居间的测量进行状态估计，降低了状态维数和计算量；然后根据相互估计的结果进行信息融合，提升估计的精度。在此基础上，对仿真结果进行了定量分析，给出了影响最终估计误差的主要因素测距精度、测量点间的基线与导航精度间的经验公式。在数值仿真中，所提方法达到了厘米量级定位精度和毫米每秒的测速精度。仿真结果表明：该方法有效，且对工程应用具有一定的参考价值。

Distributed autonomous relative navigation method for spacecraft formation near solar L2

In order to achieve high precision relative navigation of spacecraft formation in solar L2 orbit, a distributed autonomous navigation method is proposed in this paper. Firstly, the local measurement topology is formed by information interaction such that each satellite only estimates the states based on the measurement between neighbors, thereby reducing the states dimension and calculation amount. Then, the information fusion is conducted according to the results of mutual estimation to improve the estimation accuracy. On this basis, the main factors affecting the final estimation error are analyzed, and the approximation formula is proposed. Numerical simulation shows the accuracy can achieve cm order of position estimation and mm/s order of velocity estimation. The simulation results verify the effectiveness of the method and prove that the method can be applied in engineering.