Precise Orbit Determination Of Satellite And Earth Rotation Parameters Estimation Based On DORIS System

DORIS technology has become a hot research area in the field of satellite navigation and positioning both at home and abroad with its advantagesofall-weather,shortcycleandmultidata.In this paper, based on the DORIS system,the analyses and researchof the effect on the precision of orbit determinationcaused by satellite phase center deviation troposphere delay and gravity field model were made using dynamic orbit determination theory and batch processing algorithm, and the ERP parameters were calculated using DORIS data based on the average distance rate observation model. The main contents and conclusions of this paper are as follows:(1) The influence of satellite phase center deviation on orbit determination accuracyCompared the orbits obtained by two schemes to modify the satellite phase center deviation ,the one is using phase center bias values provided by data files, the other is using constant phase center bias values ,the results show that: the precision of orbits obtained by the scheme which the satellite phase center deviation were modified using phase center bias values provided by data files is better than the result from the scheme that using a fixed vector model to correct the phase center deviation. Therefore, in the use of DORIS2.0 format data for precise orbit determination, you can give priority to the use of phase center bias values provided by data files to modify the satellite phase center correction.(2) The influence of gravity field model on the orbit determination accuracy using DORIS technologyThe orbit determination results of JGM-3, GGM02C, EGM96,EGM-2008, EIGEN-GL04C and ITUGRACE-16 gravity field models in the case of 40, 50, 60, 70, 80 and 90 order were discussed. The results show that: in the same expansion order, the accuracy of orbit obtained by the scheme using ITUGRACE-16 gravity field model proved to be the best; in the case of using the same gravity field models of different developing order to determine the orbit, the accuracy of JASON-2 got the best result when using these kinds of gravity field model who developed to 50 order to make orbit determination .(3) The influence of tropospheric delay correction on orbit determination accuracyComparison between two orbit determination schemes that using troposphere delay correction values in data file and using the Saastamoinen atmospheric model to correct the troposphere delay respectively were made, the results show that the using troposphere delay correction values in data file to correct the troposphere delay will lead to a poor orbit accuracy , and the orbit results obtained by using of the Saastamoinen model meet the demand of altimetry satellite orbit accuracy .Therefore, in case of the precise orbit determination based on DORIS technology, the use of troposphere model to correct tropospheric delay is recommended.(4) Calculation of ERP parametersBased on the observation equation of the average distance change rate and the dynamic orbit determination theory and batch processing algorithm, writed theERP parameter calculating software the ERP parameters were calculated using DORIS data with a theoretical model for calculation of ERP parameters .In order to verify the relationship between the orbit accuracy and the accuracy of the ERP parameters in the orbit determination process, the ERP parameters were solved by using the DORIS 2.0 and DORIS 3.0 format data respectively. The results show that the precision of orbit determination is directly proportional to the precision of ERP parameter calculated. In order to improve the calculation accuracy of ERP parameters, it is possible to choose a more optimized orbit determination strategy.