Abstract：No singularity orbital elements combination with coordinate rotation is applied to 18-parameter ephemeris fitting model for GEO satellites in this article, which synchronously solve the singularity problem caused by small eccentricity and small inclination. Based on one year data of five Beidou GEO satellites in orbit, the fitting accuracy and stability are analyzed, and during the eclipse the fitting accuracy is quantitatively analyzed. Finally aiming at parameter’s exceeding limitation, the range of variation of parameters between 55° and 5° rotation with X axis is compared. The results show that in 2-4 h fitting arc the maximum fitting error for five GEO satellites is of only 3 cm, and the number of iterations is up to 5 times. The longer the fitting arc the worse the accuracy, and the longer the fitting arc the fewer iterations. During the eclipse, the fitting accuracy gets worse. The range of variation of parameters of 55° rotation with X axis is reduced by one order of magnitude compared with 5° rotation with X axis. There are no parameters exceeding limitation in the overall year.
CHANG Zhiqiao,HU Xiaogong,HUANG Hua et al. The Broadcast Ephemeris Fitting Algorithm Combining No Singularity Orbital Elements with Coordinate Rotation and Its Performance Evaluation=[J]. jgg, 2017, 37(7): 732-736.
