关键词: 波束指向角, 无奇点, 最小二乘拟合, 轨道根数

Abstract:

The beam pointing angle of small inclination and near-circular LEO satellite during open loop tracking of digital beam forming (DBF) is studied.Instead of the classic Kepler elements,improved elements based on the second class of no-singularity elements are proposed and satellite position and velocity in Earth Centered Inertial coordinate are converted into instantaneous orbit elements to avoid the singularity problem which occurs in orbit determination with data fitting.The position of spacecraft and relay satellite are calculated with mean orbit elements obtained by least-square fitting.Finally the computation process of beam pointing angle for DBF is presented.The simulation results demonstrate the accuracy and efficiency of the algorithm.

Key words: beam pointing angle;no-singularity;least-square fitting;orbit elements