LEO卫星可见性的快速仿真算法

Fast Simulation Algorithm for Visibility of LEO Satellites

研究LEO卫星可见性的快速算法在事件驱动和时间步进的实时仿真环境中具有非常重要的意义。首先对LEO卫星的运动特点进行理论分析,引入了"可视球冠"的概念并给出了一些新的计算公式。然后在此基础上提出了计算LEO卫星可见期的变轨交圆补偿(SOICC)算法。与以往的方法不同,本算法采用变倾角的大圆近似可视窗口内的星下点轨迹并建立了补偿方法。仿真结果表明本算法的可见期误差约为0.152%,可见始末时刻的误差约为0.92秒,具有很高的精度。

It is very important to study the fast algorithm for the visibility of LEO satellites to improve the efficiency especially in event-driven and time-stepped real-time simulation environments. A novel algorithm, shift orbit intersects circle compensation （SOICC） algorithm, was proposed to compute the visibility of LEO satellites. A new concept, visibility spherical cap, was proposed. Unlike the old methods, an arc of the approximating circle, whose inclination was different from the inclination of the satellite＇s orbit, was used to approximate the ground trace during the visibility window. Furthermore, a compensation method was built to improve the algorithm＇s accuracy. The excellent performance of SOICC algorithm was illustrated by numerical results. For the algorithm, the percentage error of visibility-time is about 0.152% and the time instant errors of entry-access and exit-access are about 0.92 seconds.