基于卫星位置与速度的北斗卫星广播星历拟合

BDS Broadcast Ephemeris Fitting Based on Satellite's Position and Velocity

提出基于卫星位置与速度的广播星历拟合算法,给出了该拟合算法的计算过程,并对传统坐标拟合算法与坐标+速度拟合算法的拟合精度及外推精度进行比较.结果表明:基于位置+速度的拟合算法是有效的,且与传统坐标拟合算法相比,该算法能显著提高拟合的速度精度,且坐标精度也略有提高.此外,在卫星轨道数据已知历元数较少时,采用坐标+速度拟合算法优势更明显.

A new fitting method based on both the position and the velocity of satellite is presented in this paper and a fitting formula is deduced. Then, the fitting and the extrapolating accuracy are compared between conventional position based fitting method and the new position-velocity based fitting method. Compared with conventional fitting method, the new fitting method shows a significant improvement in velocity accuracy, with a slight improvement in position accuracy. Besides, the new method＇s advantage is more obvious when the fitting epoch is few.