Research And Implementation Of Tracking Algorithm For Beidou Satellite Navigation B1C Signal

With the continuous improvement of the Beidou satellite navigation system in China,the Beidou B1 C signal,as a new civilian satellite signal broadcast by the Beidou satellite,has officially provided navigation,positioning and other services for global users.Satellite signal tracking is a key technology in the signal receiving device's synchronization process with the satellite signal,which directly affects the accuracy of the receiving device in extracting navigation data and determines the overall performance of the receiving device.Therefore,the research and implementation of Beidou B1 C signal tracking algorithm is of great significance.Based on the Binary Offset Carrier(BOC)and Multiplexed Binary Offset Carrier(MBOC)satellite signal tracking algorithms at home and abroad,combined with the characteristics of the Beidou B1 C signal,the Beidou B1 C signal tracking algorithm is researched and implemented.The major tasks are concluded as follows:1.The components and characteristics of the Beidou B1 C signal,including the power spectrum,correlation and anti-multipath performance characteristcs,have been studied and verified by MATLAB simulation according to the pseudo code generation method,data information encoding method and signal modulation principle of B1 C signal.2.The tracking principle of satellite signals has been studied using the typical delay-locked loop structure.The tracking structure of the satellite signal is mainly composed of the carrier frequency tracking loop,the carrier phase locked loop and the pseudo code tracking loop.The performance of these loops has been analyzed;a comparison among the discriminator algorithms for various loops and the corresponding overall errors has been made.3.The BOC(1,1)joint tracking algorithm and the QMBOC joint tracking algorithm for the Beidou B1 C signal have been proposed according to the characteristics of the Beidou B1 C signal and the pseudo correlation function tracking algorithm.These two algorithms enhance the tracking accuracy by making full use of the energy of Beidou B1 C signal.Moreover,the joint tracking algorithms and the Pseudo-correlation function tracking algorithm are simulated and analyzed,showing that the joint tracking algorithms are more accurate than the Pseudo-correlation function tracking algorithm.When the signal-to-noise ratio is high,the QMBOC joint tracking algorithm has higher tracking accuracy;when the signal-to-noise ratio is low,the BOC(1,1)joint tracking algorithm exhibits higher tracking accuracy and better stability.4.Implement the Beidou B1 C signal tracking algorithm.The overall function module of the tracking algorithm has been classified in detail;the FPGA design and DSP design of each module have been completed;the RTL module diagram of the module and its detailed description of each port have been given.Furthermore,the modelsim simulator was used to simulate and verify each module,and the correctness of each module design was verified.