Design and verification of GPS IF software analogue signal simulator
Huang Feijiang1, LuXiaochun2,3,Li Xiaoyong4,ZhangWenxi1,Liu Guangcan1
COMPUTER MODELLING & NEW TECHNOLOGIES 2014 18(12B) 247-252
1Department of Electronics and Communication Engineering, ChangshaUniversity,Changsha 410022, China
2National Time Service Center, Chinese Academy of Sciences, Xi’an 710600, China
3Key Laboratory of Precision Navigation and Timing Technology, Chinese Academy of Sciences
4School of Information and Electronic Engineering, Zhejiang University of Science and Technology, Hangzhou 310023, China
For the need of GPS intermediate-frequency(IF) analogue signal in various dynamics and disturbances, this paper has proposed a design to realize GPS IFsignal simulator with software. Based on the given GPS satellite clock error and GPS signal transmission error, it analyzes their influence on signal acquisition and tracking as well as position calculation; deduces the mathematical model and analogue method of the ionospheric disturbance, the tropospheric disturbance and the multipath interference in the transmission of the navigation signal; designs the GPS IF analogue signal method based on software and chooses to use MATLAB software to realize GPS C/A Code IFsignal simulator in L1 frequency. Through a software receiver which can successfully acquire and track the actual GPS signal, it verifies the correctness of the IF signal simulator; uses GPS IFsignal simulator into GPS receiver development and gets arbitrary signal to noise ratio and the analogue GPS signals in various dynamics and disturbances for the developers of GPS receivers to investigate the influence of various errors on the receivers.