The Design And Realization Of The Dual-Frequency GNSS Receiver

The Global Navigation Satellite System (GNSS) has been widely used due to its rapid development over the past decades. Most traditional satellite navigation receivers only use single constellation (such as GPS or GLONASS) to provide users positioning services, and the receivers based on this technique have lots of disadvantages, most of which can be greatly compensated by the multi-constellation receivers. As the Compass satellite navigation system in china growing more and more flawless, it becomes very feasible to design a multi-constellation receiver which can receive both GPS and Compass signals at the same time.The need to design a dual-frequency receiver was deeply analyzed in this thesis, and the theoretical analysis along with the principle design of the receiver was also proposed in it. Meanwhile, the parameters corresponding, link budget and chip choosing have been accomplished. The Impedance matching of radio frequency and PCB was simulated. The electromagnetic compatibility and signal integrity of small and high-density PCB were deeply investigated, in which some key signal lines were specially designed and simulated. The author also designed the PCB and run some essential tests, through which the super heterodyne structure of RF front, the general baseband signal processing module using FPGA and DSP were proved to be executable. Moreover, this design could provide users greater experience owing to its flexibility of algorithm processing, software update,etc. This solution was able to stimulate the application of the multi-frequency receivers.