Research On The Software Radio GPS Receiver

With the development of the communication, new system and standards are presented continually. The existent cycle of the communication product has become shorten and the expense is going up. In this condition, traditional communication system which is based on the hardware is no longer adapt to the new complexion. So we contrapose the actuality of mobile communication and put forward a new defined wireless communication system called software radio. It is the third transform in the wireless communication after simulation to digital and immobility to mobile.Software radio has advantages of more effectively saving hard resource, more conveniently and more flexible renewing system. A kind of implementation method on soft-GPS receiver is proposed for software radio in this paper for those advantages. In this paper, the knowledge of GPS and direct spread spectrum sequence is introduced, the de-spread spectrum arithmetic and the de-modulation arithmetic for GPS signal are studied. And several kinds of implement method on PN code synchronization and carrier synchronization are specified. This paper has selected the matching-filter method as code synchronization arithmetic and COSTAS loop method as carrier synchronization arithmetic by comparing those methods. And this paper deduces these two kinds of method theoretically. In addition, the GPS signal resource is generated in simulink of MATLAB. Finally, we design a GPS data collection card which based on the USB interface. This kind of implement method of new GPS receiver can be extended to other domain yet. The development foreground of this implement method is very well.The design and implementation process of software single-frequency GPS receiver which investigate in this article is laid a foundation for the further design of multi-frequency GPS receiver. Thereinto, the GPS date collection card is also used to multi-frequency GPS receiver, and the design and realization of arithmetic can be used for the multi-frequency GPS system.