A Key Technology Of Satellite Clock Prediction

With the urgent needs of satellite navigation and positioning in the modernization military war and the rely of national economy increasingly satellite navigation and positioning, satellite navigation and positioning has become a dispensable important component to modern social. High-precision satellite navigation and positioning, timing measurement, posture measurement and lateral measurement techniques depend on high-precision spatial reference and time reference. Under the premise of high precision time synchronization, the affect of satellite clock error on satellite navigation and positioning is extremely important.This thesis researches the satellite clock error prediction technology, Emphatically resolve a key technology of satellite clock error prediction under the unusual circumstances, analyzes the main definitions of the satellite clock indictors, such as frequency accuracy, frequency bias, frequency drift rate and temperature frequency characteristics. Through the study of the affect of frequency drift rate and temperature-frequency characteristics on the long-term performance of the satellite clock, the methods to improve these two characteristics are proposed. By summarizing up the advantages, disadvantages and accuracy of these satellite clock error prediction methods, such as quadratic polynomial, Kalman filter and traditional grey system model. This thesis proposes a new improved grey system model for the satellite clock error prediction in unusual circumstances. Thesis analyzes the characteristics of satellite clock error in unusual circumstances frequency adjustment, phase tuning satellites clocks switch, establishes reasonable prediction model to detect unusual values to improve the accuracy of the satellite clock error prediction.