GPS星历分为预报星历和精密星历，而利用预报星历计算卫星坐标是一项基本而又重要的工作，对于单点定位和动态定位等有重要的意义！-GPS ephemeris is divided into the ephemeris and precise ephemeris, the ephemeris to calculate the satellite coordinates is a basic and important work has important significance for the si