Research On Key Technology Of Beidou Navigation Message Data Processing

The navigation message is the key of the satellite navigation system and the basic data of the satellite navigation and positioning system.The system provides positioning,timing and information required for data aided signal acquisition to the user through broadcasting navigation message.In order to achieve the best navigation and positioning performance of Beidou satellite navigation system,we should study the content of navigation information,the data processing method and the problem of using navigation information of the Beidou System,then verify the algorithm of navigation message data processing by special software.In this paper,the practical application of Beidou satellite navigation system as the starting point,the research and analysis of Beidou navigation message data processing methods and processes are carried out.The main research content can be divided into the following aspects:1.This paper introduces that the data processing from the original satellite signal to the final navigation data code sequence is introduced in detail,the key problems that need to be solved and deeply studies and analyzes the various links and core algorithms of data processing.For the characteristics of the actual Beidou B1 frequency signal data received,the data down sampling processing,reduce the amount of data to improve computing speed.This paper proposes an accurate estimation strategy for the carrier frequency of Beidou satellite signal.The algorithm can effectively improve the accuracy of carrier frequency estimation of Beidou satellite signal,and the capture is fast,reliable and simple.Tracking processing module,comparative analysis of a variety of identification methods of the lock ring,PLL and code ring in the carrier tracking loop,and according to the practical application select the optimal solution.Using the actual Beidou satellite data to verify the good performances of the selected tracking loop program.The signal processing of the tracking output signal is synchronized,and the binary data extraction of the navigation data parameters is carried out according to the Beidou satellite navigation system spatial signal interface control file(BDS-SIS-ICD-2.0).At the same time,the performance of Beidou and the same type of Navigation by Satellite Timing and Ranging Global Positioning System navigation data processing system is analyzed.2.Based on the deep analysis and research on the key technology of the Beidou navigation data processing,a Beidou navigation message data processing system platform is constructed.The software system can capture and track B1 signal frequency of Beidou or L1 signal frequency of GPS satellite,synchronize the bit and frame,decode and processes the navigation data message.The software platform is tested by the actual satellite signal data,and the effectiveness and feasibility of the Beidou navigation message data processing system are verified.