面向小倾角近圆低轨卫星的DBF波束指向角研究

研究了DBF开环跟踪过程中面向小倾角近圆低轨卫星的波束指向角问题,为避免采用数据拟合进行轨道预测出现的奇点问题,文中引入改进的第二类无奇点根数代替经典开普勒根数,将地心惯性坐标系下的卫星位置速度转化为瞬时轨道根数。采用最小二乘法拟合得到平均轨道根数,以此为参数计算出航天器和中继星的位置,并给出了DBF波束指向角的计算流程。仿真结果验证了文中算法的正确性和有效性。

Study of DBF Pointing Angle for Small Inclination and Near-Circular LEO Satellite

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.