深空探测器三程多普勒建模与算法实现

Modeling and Algorithm Realization of Three-Way Doppler for Deep Space Exploration

针对高精度深空探测多普勒应用,提出了一种间接使用中心天体、航天器的速度与加速度进行多普勒建模的方法。避免了计算机字长截断误差、星历表插值误差对建模精度的影响。使用该算法对环火星探测器进行了连续1周的多普勒计算,通过常规的距离差分方法检验了算法的正确性,对计算的1小时多普勒数据进行10阶多项式拟合,拟合后数据残差小于0.002 mm/s.分析结果表明该算法计算多普勒结果正确,计算精度较常规距离差分算法在精度上得到1个量级的提升。

Aiming at the high precision Doppler application for deep space exploration,a new algorithm for Doppler modeling using the velocity and acceleration of the central object and the spacecraft is proposed.The algorithm avoids the truncation error induced by the direct use of ranging and the positional uncertainty of ephemerides interpolation.Continuous Doppler computation for a Martian orbiter lasting one week is performed,and the general computation algorithm using ranging difference is used to test the correctness of the new algorithm.In addition,one-hour length of the Doppler data is fitted with a polynomial of order 10,and the residual error is less than 0.002 mm/s.The analysis results show that the new algorithm is correct and is approximately one order of magnitude improvement in accuracy compared with the conventional modeling algorithm.