The Methods And Practices Of Reduced Dynamic Orbit Determination Technique

In the recent20years,persons put forward high demand on precise orbit determination about the Leo satellite following the aid of the scientific instruments of the Leo satellite for application and research of the space science technology such as ocean altimeter, refine of gravity field, research of ionosphere and so on. On the one hand, persons have very strong requirements on real-time of orbit determination method; on the other hand, persons wish to accuracy of orbit determination more and more high. The requirement of accuracy already range nearly meter of60s up to the centimeter level now. Based on key problems and core technology about orbit determination of the Leo satellite, this paper detailedly research on several key problems for determination of the Leo satellite orbit using MATLAB7.0and BERNESE5.0software platform. The main work and study are as follows:1,The paper expounds the basic theory about the GPS-Based orbit determination of the Leo satellite, analyzes the choice, transform and application between the time system and coordinate system, deduces the detailed data model and the relevant formulas for orbit determination of the Leo satellite and analyzes the error sources that of GPS-Based orbit determination of the Leo satellite and give some specific corrective measures.2,It is very meaningful that satellite clock bias forecast is used for nearly real-time orbit determination of the Leo satellite,so this paper researches and simulates the satellite clock bias that influences GPS-Based orbit determination of the Leo satellite. Brought forward two satellite clock models that are GM (1,1) cycle and GM (1,1)cycle-AR(p) based on the analysis of the gray model GM (1,1) and GM (1,1)-AR(p) model, and get some useful conclusions. In addition, we combines the neural network and the gray model, and propose the satellite clock bias forecast based on the gray BP neural network. In the IGU super-fast satellite clock bias forecast, verify the effectiveness and pragmaticality of the method.3,The paper detailedly discusses the theory and mathematical model for three methods of orbit determination of the Leo satellite:geometric method, dynamic method, reduced dynamic method. Aiming at three methods and taking the CHAMP satellite for example, this paper researches and analyzes the advantages and disadvantages of the three methods, discusses and compares the precision of orbit determination with different methods. Besides, this paper discusses and analyses precision influence for orbit determination of the Leo satellite because of different error model.4,The paper detailed researches the dynamical method and the reduced dynamical method combining the measured data of CHAMP. Study some factors such as the pressure compensation model and the accelerometer data,which impact on orbit determination of dynamical method based on factors. Meanwhile,study the pseudo-random speed pulse and pressure compensation model which have a role of absorption and regulatory for the error of model in the orbit determination of reduced dynamic method.