Gps Third Generation Of A New Civil Signal And Its Application In The Analysis

In 1999, IGEB (the Interagency GPS Executive Board) signed documents about how to implement the L5 signal and measures that the USA government would take , so as to ensure the L5 signal compatibility with the existing system and carriers after the application of L5 signal. Nowadays, the technology about L5 signal is very perfect abroad. Along with the development of the technology and the requirement of human, the USA government will increase the third civil signal-L5 signal in the GPS satellites that will be emitted in 2008.This thesis investigates the third civil signal of GPS. Firstly, it introduces the background and developing status of the third GPS civil signal (LS signal). Secondly, it introduces the frequency selection, EMC(Electromagnetic Compatibility), the basic generation theory and modulation of the third civil signal(L5 signal), including LS ranging code, Forward Error Correction, QPSK modulation and Neuman.Hoffman code, and then analyzes its relevant characteristics. Thirdly, on the basis of the tracking theory of GPS C/A code, it gives out the tracking theory of GPS L5 signal, and then discusses the different performance analyses when tracking using the data channel, dataless channel and both data and dataless channels in the case of given tracking loop. Lastly, it analyzes the theory of the linear combination for the third civil signal and the existing GPS signals, so as to eliminate the effects of ionosphere, thermal noise and multipath and troposphere as much as possible. After every analysis, this thesis gives the simulated results and the results analyses.