Gps Receiver Anti-jamming Methods Of Research,

With the development of GPS modernization and China's Compass Navigation Satellite System (COMPASS) building, satellite navigation and positioning will be more widely used and have a significant market prospects. Because of the traditional hardware-based GPS receivers have disadvantages on flexibility and the cost of upgrading, This dissertation works on the research and implementation of GPS software receiver. GPS software receiver based on the Software Radio method which have the flexible function, open structure,easy upgrading. GPS software receiver can load different software programs to different functions or complex high-performance algorithms when use general hardware platform. It not only has the navigation and positioning functions, but also has significant advantages in the areas of high-performance navigation and positioning algorithm and GPS anti-jamming research.After introduced GPS system components, signal and C/A code characteristics, positioning principle in this dissertation, design and implementation of a complete GPS software receiver system based on software radio architecture. The hardware of system includes RF front-end and IF data collector: RF front-end which is used for receiving GPS signal, down conversion, amplifier gain and A/D conversion, is made up of active antenna, filter and front-end processing chip; IF data collector based on FPGA and USB2.0 transmission interface is responsible for collection and transmission signal. The software of system based on PC is used for implementation GPS software receiver signal processing, which consist with acquisition, tracking, navigation data decoding, satellite position calculations, pseudorange calculations and receiver position calculations. In software focuses on the analysis of implementation of the fast acquisition based on circular correlation and tracking, test the key parameters and performance indicators. Finally, debug and verify the whole system. It work properly and achieve accurate positioning.In addition, the dissertation do research in anti-interference method of GPS based on GPS software receiver system. Firstly, introduce some types of the interferences in GPS and analyze the effect of interferences on the receiver property. The dissertation gives three anti-interference principle and process flow: the time and frequency anti- interference processing, the space anti-interference processing, the joint space-time anti-interference processing. Finally, compare and verify the performance of these GPS anti-interference method by Simulation based on Matlab.In a word, design and implementation of a complete GPS software receiver system based on software radio architecture. With the development of GPS Modernization and oher navigation satellite system (COMPASS) building, as well as people demand for receivers with high precision and anti-interference ability, GPS software receivers will be widely popularized.