改进的能量守恒方法及其在CHAMP重力场恢复中的应用

摘要

An efficient method for gravity field determination from CHAMP orbits and accelerometer data is referred to as the energy balance approach. A new CHAMP gravity field recovery strategy based on the improved energy balance approach is developed in this paper. The method simultaneously solves the spherical harmonic coefficients, daily integration constant, scale and bias parameters. Two 60 degree and order gravitational potential models, XlSM-CHAMPOlS from the classical energy balance approach, and XISM-CHAMP02S from the improved energy balance, are determined using about one year's worth of CHAMP kinematic orbits from TUM and accelerometer data from GFZ. Comparisons among XISM-CHAMP01S, XlSM-CHAMP02S, EIGEN-CG03C, EIGEN-CHAMP03S, EIGEN2, ENIGN1S and EGM96 are made. The results show that the XlSM-CHAMP02S model is more accurate than EGM96, EiGEN1S, EIGEN2 and XISM-CHAMP01S at the same degree and order, and has almost the same accuracy as EIGEN-CHAMP03S.