ABSTRACT
GPS technology has been developing rapidly in recent years because of the advancement of electronic technology and communication technology as well as the appearance of new software and hardware for exploration. It developed from the simple point localization and the relative localization to the difference localization and the macrozonality difference localization, from reception to the data post-processing and then real-time data processing. GPS is a specially-structured micro-processor designed for the rapid realization of various digital signal algorithm processing; it possesses unique sets of instructions, flexible programming, high operating speed and is easy to explore. Compared with other monolithic processors, GPS is characterized by small volume, high speed, low power loss and high reliability, thus it suits to process real-time GPS signals which are very complex because a high speed GPS digital signal processor can reduce the renewing rate of digital to 0.1 second.
This thesis firstly makes a brief review on the background, current studies of this subject and introduces the appearance, development and characteristic and some related key technologies of GPS. And then the author carries on DSP processing and designs the hardware of GPS digital receiving system. The whole system consists of two modules: receiving module and processing module. The receiving module takes GPS as a core, mainly dealing with the design of connection circuit between GPS and PC machine, between GPS and DPS; the processing module takes the DSP processor as a core, also throwing efforts on the design of the connection electric circuit between GPS and PC machine. Finally comes the design of software, including system initialization programming, receiving and judgment of navigational telegram text, the design of system string correspondence, the programming design of the navigational telegram text collection and calculation, the design of signal processing module, and the author proves the correctness of the signal processing module through simulation in the DSP experiment box.
