星上天线波束指向角的简化算法

Simplified Algorithm of Beam Pointing Angle for On-board Antenna

摘要:

介绍了一种星上天线波束指向角的简化算法。该算法通过建立当前时刻与CGCS2000坐标系重合的惯性坐标系，实现CGCS2000坐标系到轨道坐标系的直接转换。和星上天线波束指向角通用算法相比，该算法不需要计算随时间持续变化的J2000惯性坐标系到CGCS2000坐标系的转换矩阵，更不用考虑章动岁差模型与极移模型的选取所带来的计算误差。仿真计算结果表明：两种算法的计算误差均在米级，而简化算法大幅降低了乘法和加法运算的次数，在计算误差与计算量上都能满足星上计算的需求。

Abstract:

A simplified algorithm of beam pointing angle for on-board antenna was introduced. The algorithm established the inertial coordinate system which coincided with the CGCS2000 coordinate system at the current time, and the direct transformation from CGCS2000 coordinate system to the orbit coordinate system was realized. Compared with the general on-board beam pointing algorithm, the proposed algorithm does not need to calculate the time-varying conversion matrix from J2000 inertial coordinate system to CGCS2000 coordinate system, and does not need to consider the calculation error caused by the selection of the nutation-precession model and the pole shift model. The simulation results show that the calculation errors of the two algorithms are in the meter level, and the simplified algorithm greatly reduces the times of multiplication and addition, and can meet the needs of on-board calculation in terms of calculation error and calculation amount.