Research For Algorithm Of GPS Signal Simulation Source In Complex Environments

The successful development of the Chinese Beidou system makes our countryno longercontrolled by others in all respects.However, no doubt, the U.S. GPS system has an absoluteadvantage in the international market. So it is still very necessary to have various studies on theGPS.The simulation of the GPS signal is not only used to test the performance of the GPS receiver,verify the system-level GPS simulation, but also can be used to deception jamming, causing thereceiver or navigation device failure. This thesis design the simulation based on thecommonreceiver and software receiver to generate the GPS IF digital signal which can causedeception position of the specified receiver by the data playback via USB.The main work is asfollows:1. The paper analyzesthe GPS signal structure firstly, then proposes the mathematical model ofthe GPS IF digital signal.And finallyit designs the system architecture of GPS signalsimulator.2. We collect the original navigation message by OEMStar receiver, and focus on analysis of thedata content of the navigation message based on ICD-GPS-200C. The paper gives theextrapolation algorithm of navigation message parameter to generate the navigation messageat any time. And we develops the GUI for predicting the navigation message.3. We acquire the GPS signals for any location in any environment by GP2015. By the digitalsignal processing in the software receiver, the paper analyzes the signal delay information toobtain the initial parameters of satellites that we need at a false positioning satellite, such asthe initial code phase, doppler frequency and so on.4. At the end, the paper makesuse of the software and hardware receiver to test the GPS signalsgenerated by us. And the research work of this paper is verified to be feasible and correctthrough the positioning contrast between the real signal and simulated signal.