GNSS Receiver Time Calibration Algorithm Design And Emulation Analysis

Time is the indispensable base quantum of human production and in our lives.In GNSS systems,high precision time transfer can make the precision of navigation and positioning to achieve a high standard.This thesis mainly analyzes and designs the time comparison algorithm of the GPS,Galileo,GLONASS and COMPASS four satellite navigation and positioning systems.We consider the receiver into the single frequency receiver and the dual-frequency receiver.Finally we compare and analyze the clock difference image.The main content of the paper is as follows:(1)Determine the position of the satellite in the planning time point coordinates: Using satellite ephemeris calculating method for GPS,Galileo and COMPASS satellite space position,using satellite orbit equation calculation method to obtain the GLONASS satellites space position,finally obtaining the satellite orbit simulation which needs position coordinates of the ground.(2)Because the GNSS system has delay,in this paper the GNSS systems of all kinds of revised are calculated.It includes the four systems ionosphere delay calculation,tropospheric delay calculation and the earth's rotation effect.(3)GNSS pseudorange observation method is used to design a total depending on the time alignment algorithm and using matlab software simulation to analyze on it.The simulation of single frequency receiver and dual-frequency receiver time alignment algorithm shows that dual frequency receiver measured ionospheric delay revised is more accurately.(4)The paper has researched the GNSS combined common view: Completed the GPS and Galileo system time conversion,satellite clock error of GPS,GLONASS and Galileo was calculated,and the time of GPS and Galileo system fusion algorithm has carried on the simulation analysis.