Based On The Research And Realization Of Gps Baseband Signal Processing In The Fpga

Global Positioning System(GPS) is a satellite navigation system established to solve the navigating and positioning problems on land or sea and in the air. As a new generation of satellite navigation system, it not only has global, round - the - clock, continuous, high - precision navigating and positioning functions, but also possesses excellent interference immunity and confidentiality. Therefore, the development of GPS navigation technology has become ever more important in the advancement of navigation industry.The core parts of GPS receiver baseband signal process module - signal acquisition module, tracking module, were investigated in this paper. On the GPS system composition and structure analysis, combining the characteristics of engineering design optimization algorithm is presented, and the implementation scheme, finally implemented on the board.The contents of this paper include the following aspects:1) The composition of GPS simply introduced, and the structure of GPS satellite signal is introduced in detail, including the carrier signal, the generation of PN code and the detailed content of navigation message.2) GPS signals in the capture of the more traditional serial, parallel and capture the advantages and disadvantages of capture, the resources and the performance of the reasonable selection, and eclectic mix of parallel capture scheme, reduce the consumption of hardware resources, accelerate the speed of the signal, and improve the capture capture performance.3) A non - eoherent DLL is used to track the C/A code. The local carriers from carrier tracking loop turn the input signals into the baseband signal, and the baseband signals multiply the two different phase sequence of the local yards, then deal with cumulative results, at last, put the code phase and current carrier frequency into carrier tracking loop.4) Costas loop is used as the carrier tracking loop. With the code tracking loop coupling tracking module. In this paper, a novel approach by using FPGA to capture the GPS signals and track the C/A codes is employed. According to the characteristics of FPGA for engineering design, and implementation in resources and performance is achieved reasonable balance.