Research And Implementation Of Acquisition Algorithm For GPS Signal Based On FPGA Platform

GPS is the most widely used satellite navigation system. GPS software receiver has beendeveloped. At present, the research hotspots of GPS include single-chip GPS receiver, compatibilityreceiver, high precision and sensitivity, real-time acquisition and tracking, low power consumptionand small size and so on. In addition the basic system of Compass regional satellite navigationsystem has been completed, so, the depth study of GPS software receiver for the development ofour satellite navigation technology is of great significance.This paper is about acquisition key technologies studies of GPS software receiver. In this paper,an improved algorithm is proposed and an acquisition system on FPGA development platform isimplemented. The research and results are as follows.(1) The GPS system is brief introduced. GPS/Compass software receiver hardware platform isbuilt, laiding a foundation for implementation of software receiver and studying of Compassreceiver.(2)The theory of common acquisition algorithm is studyed. According to the frequency domainparallel code acquisition algorithm, the improved algorithm samples5714points of data to1024points during one period using average sampling technique, obviously reducing the calculatingamount and largely increasing acquisition speed.(3)This paper describes the functional modules of acquisition system. Then, by using GPS IFsignal, the simulation of acquisition system is built. Compared with the experimental resultsof MATLAB simulation tool, the performance of the improved algorithm is fully proved.(4)In order to verify acquisition results error does not affect the tracking results, the jointdebugging between the acquisition system and the tracking system is implemented, and the result ofsystem debugging is further evidence the validity of the acquisition algorithm. The acquisitionsystem on FPGA development platform is successfully achieved.