Algorithm And Implementation Of Baseband Processing Of Beidou 2nd Navigation Reciver

With the rapid development of modern information technology, satellite navigation and positioning technology can be extended to the different fields such as navigation, surveying and mapping, astronomy, military and communication. Many regions and countries are engaged in the development and application of satellite navigation receiver. With the publishing of the ICD files of beidou satellite navigation system, the second generation of beidou navigation(BD2) system which is researched and developed independently in China is also gradually completely. As the key performances of the BD2 receiver, the study of baseband signal processing part has very important meaning in the development of satellite navigation industry in the future. Therefore, this article focuses on signal capturing and tracking algorithm in baseband signal processing. Then we design modules with the hardware description language for simulation. The points of the work are included in the following three aspects:First of all, this paper introduces the features, modulation mode and structure of the BD2 signals. And it analyses the organization and generation of navigation message, carrier, pseudo-random code. Then this paper expounds the structure of receiver, positioning principle, the catch of the original observation and the basis of the down converter theory in detail. In the end we build the sender model and the receiver model of the BD2 system in the Simulink platform according to the theoretical analysis.Secondly, this paper studies the principle and algorithm of baseband data processing of the BD2 signal capturing. Then we analyse and compare the time serial domain correlation capture algorithm, the parallel capture algorithm based on matched filter, the parallel capture algorithm based on FFT, the parallel capture algorithm based on PMF/FFT. And we respectively analyse the modeling and simulation result of the PMF/FFT algorithm. Then the paper researches the principle and algorithm of the BD2 signal tracking and respectively analyzes the structure and characteristics of the carrier tracking loop and code tracking loop. Then paper designs the whole framework of the tracking algorithm and sets up the tracking algorithm model in Simulink platform according to the theoretical analysis.Finally, this paper puts forward the hardware design scheme and realizes the algorithm with Verilog HDL language logic on the FPGA hardware platform. Then it detailed analyses the important modules of the design scheme of digital baseband processing and gives the actual interface list, ideas for design, module structure. we describe the process of its implementation and use Modelsim to simulate the code. In the end, the paper gives the resource usage, the hardware simulation results, comprehensive report and validates the performances of the algorithm.