这是一个SP3格式的精密星历的数据文件，具体的格式说明，希望能帮到你-This is a SP3 precision star of the calendar format data files, specific format indicates that, the hope can help you

几种mht格式的rinex文件，如sp3-c,rinex2.0等，非常好用-MHT format of rinex file, it is very nice

读取sp3文件（P类型）中的精密星历，并用拉格朗日多项式九阶内插法计算卫星位置-Sp3 read the file (P type) in the ephemeris, and calculates the satellite position with a ninth order Lagrange polynomial interpolation