A Study On The Orbit Determination Of GEO Satellite With Systematic Errors

Compass Satellite Navigation System of China composes of three types of satellite, geostationary earth orbit (GEO) satellite, inclined geosynchronous orbit (IGSO) satellite and medium earth orbit (MEO) satellite. GEO satellite plays an important act for navigation and position, as well as communication. One of the most important problems in the data processing of GEO satellite orbit determination (OD) is the validation and control of systematic errors, such as satellite clock error, receiver clock error, time delay of satellite transponder and tracking station equipment bias. The thesis focuses on the research of the influence and estimation for systematic errors in GEO satellite OD. The main research work is as followings:(1) The effect and detection of systematic errors on GEO satellite OD are studied by residual analysis of observation data. The detection ability of systematic errors is researched based on tracking station distribution.(2) A geometry OD method considering systematic errors for GEO satellite is developed. The simulated examples show that the influence of systematic errors on the OD can be efficiently weakened by the new method, and the precision of OD is greatly improved.(3) The influence of systematic errors on position dilution of precision (PDOP) is analyzed for a GEO satellite. A geometry OD method based on PDOP weighting and systematic parameter estimating is presented. The results show that the ability of weaken systematic errors and the precision of OD can be further improved by using the new method.(4) The solving ability for systematic errors of tracking station for geometry OD is analyzed. Take tracking station bias for example, a simulated numerical example is performed. We can draw a conclusion that the number of solving tracking station bias is less than or equal to the number, which is the difference of station number and the number of state vector and other estimated parameters.(5) The effect of increasing the number of tracking station and changing the geometry structure on PDOP is analyzed. It is found that the added tracking station had better lie outside of old tracking network.(6) A two-way Kalman filtering for GEO satellite orbit determination is put forward to weaken the effect of systematic errors. And its principle is easy to carry out. It also achieves the goal to improve the precision of OD in the experiments. (7) A two-way Kalman filtering with eliminating parameters is proposed. The main idea is to estimate the systematic errors parameter in. the forward filtering by eliminating the local parameters, and in the backward filtering the local parameters are recovered by fixing the systematic parameter. The results of simulated examples show that it can control the influence of systematic errors on the OD effectively with a high precision.(8) The basic theory of dynamic OD is introduced, especially for the effect of the linearity of observation and dynamic mode errors. The effect of perturbing force on GEO satellite is analyzed. A dynamic OD method considering systematic errors is presented. The results of simulated example show that the influence of systematic errors on the OD can be efficiently controlled by solving the systematic error parameters, satellite state and mode parameters' simultaneously.