Study Of Navigation Message Design Technology In Satellite Navigation System

Satellite navigation message is the basic data of the Satellite navigation system for positioning and navigation, which design quality will directly influence the first location time of the receiver without the ancillary information, the utilization rate of radio channel data resources, the scalability and expansibility of the message structure, etc. Based on the background of'the global satellite navigation system simulation software', through the analysis and comparison the three kinds of navigation message structures of GPS, GLONASS and Galileo, puts forward on the navigation message performance evaluation methods. This paper gives the optimization design principle of the Satellite navigation message, finally, uses software to simulate and generate the Galileo navigation message. The main contents of this paper are as follows:Firstly, this paper elaborates the basic concepts and basic theories of the satellite navigation system. The paper discusses the content and structure of the navigation message, such as: the satellite almanac, clock fixed parameters, navigation service parameters and ephemeris. Then the paper introduces respectively GPS NAV navigation message, GPS CNAV navigation message, GLONASS navigation message, Galileo F/NAV navigation message and Galileo I/NAV navigation message. The paper analyses the message performance of three kinds of navigation system deeply.Secondly, this paper analyses the structure of the three kinds of satellite navigation message, then puts forward on the method to estimate the performance of the navigation message, and uses this method to estimate the performance of these three navigation message. Then this paper separately relates and analyses the ephemeris precision, the time of receiving a complete set almanac, the first locating time, the data resources utilization, the message structure scalability, and the navigation message error-controlling codes properties.Thirdly, this paper studies the optimal design of the navigation message, and designs the data structure of the navigation message, the message broadcast mode and error-controlling codes and so on respectively.Finally, this paper simulates the Galileo navigation message, realizes the Galileo navigation message by software. This paper gives some principle and method to the navigation message design of the second generation COMPASS navigation system.