Implementation Of GPS L1 Signal Processing Technology

With widely used GPS for the area of navigation, aviation, aerospace, transport surveying, resources exploration, communication and meteorology, the research of satellite navigation receiver is becoming a hot scheme in the modern world. The thesis deeply researchs the signal processing of the GPS L1 and implements the hardware platform of the signal processing of the GPS. The project proposed in this thesis satisfies the flexibility better which the GPS software receiver need.Based on analyzing the fundamental principle of spread spectrum communication the main part of the paper introduces the composition of GPS system and the characteristics of the GPS signal and primarily analyzes operational principle of GPS receiver, combining with the system structure of the GPS receiver.Through studying on the kinds of acquisition schemes of GPS receiver deeply and the deeply analyzing with complexity of the system realizing, the fast parallel acquisition scheme based on FFT is chosen. The carrier tracking loop and code tracking loop are designed. The feasibility of the system is simulated and verified by MATLAB.In guide of the results for the theory, the hardware platform of the GPS receiver is designed, focusing on the description of design process of the RF circuit and the FPGA circuit, as well as wiring and electromagnetic compatibility to consider in the PCB design process. In RF design, including the parameters choice and circuit design in all levels of signal filter, circuit design of crystal and the gain calculations of the receiver; In the design of the baseband signal processing platform, including the design of the download circuits for the FPGA, power supply circuit, clock circuit, extended memory circuit , input and output circuit. Finally, the correctness of the program is verified by the hardware debugging of various parts of the circuit. Based on the basis of the above work, the paper mainly analyze the FPGA implementation of the parts of GPS signal acquisition and tracking. Based on FPGA time sequential simulated waveform, it demonstrates that the system can successfully acquit and track GPS signal.