Accuracy Analysis of Geopotential Coefficients Recovered from In-situ Disturbing Potential by Energy Conservation Method

The characteristics of the normal equation created in recovering the earth gravity model(EGM) by least-squares(LS) adjustment from the in-situ disturbing potential has been discussed in detail.It can be concluded that the normal equation of this type of problems depends only on the orbit.Based on this characteristic,whether a reference field is used or not has no effects on the LS solution is explained.Staring from this point,four sets of disturbing potential on the orbit with different level of noise have been simulated and used to recover the EGM.The results show that on the current accuracy level of the accelerometer calibration,the accuracy of the EGM by LS is not sufficient to reflect the time variability of the EGM as the dynamical method has revealed.