Implementation Of Software Receiving Algorithm For Gps Weak Signal Acquisition And Lan Collaborative Process

Reseach on GPS weak signal becomes the hot spot of GNSS system, as the accuracy and real-time performance are more highly demanded. This thesis is aimed at how to level up the performance and efficiency of software GPS weak signal acquisition, where the weak signal acquisition algorithm and the LAN collaborative platform are emphatically researched.In aspect of weak signal acquisition algorithm, the mitigation methed of cross-correlation interference among the GPS signals is mainly researched. Firstly, we get the relation between cross-correlation interference and the Doppler frequency deference through a set up model for received signals and the following derivation. Then the GPS weak signal acquisition system is designed which includes interference detection, reconstruction of strong signals, mitigation algorithm and calibrating algorithm of extending the coherent integration time. The system parameters are presented by the simulation. Feasibility of the algorithm is verified through the real GPS data, and the improving performance is tested and analyzed.In another hand, in order to improve the effitiency of GPS weak signal acquisition system, the idea of distributed collaborative processing and C/S model are reffered. Through the mix-programming of Matlab and MFC, the algorithm and controlling programming are separated which has made the weak signal acquisition algorithm embedded into the LAN collaborative platform. After testing, the improvement of the system efficiency is presented and analyzed.