Simulation And Research Of GPS Satellite Navigation Signal

GNSS satellite signal simulator can simulate different signals in various kinds of transfer environment, and also can accurate simulate the received signal by according to the motion state of the user receiver,which is indispensable test equipment to research GNSS systems and develop GNSS receiver. Satellite navigation signals is the basis of research the satellite signal simulator, in this paper, two modulation method BPSK and BOC are adopted to simulate GPS satellite signals for deeply studying. The main contents and methods are as follows:Firstly, GPS satellite navigation signals need to understand the principles of GPS navigation and positioning system, the simulation of satellite signals needed to set various parameters of the satellite. This article focuses on the simulation parameters, analyzed satellite position, error source, delay parameters, carrier status and distribution of visible stars, given the spatial position estimation process and a variety of error model calculations. To solve the visible satellite point,proposes a satellite visibility model calculation by influence of moving receiver, thus, accurate simulation satellite signals received by the receiver.Secondly, based on the analysis of GPS signals, using MATLAB simulate and research the modern satellite navigation signal, focusing on BOC modulation signal generated by the BOC system. By comparing performance between the modulated PSK-R modulated signals and BOC modulation signal, research the using of signal bandwidth, anti-noise and anti-multipath performance of the two systems signal from the signals spectrum offset, frequency range and the signal-related, by signal spectrum analysing the SSC and using NELP method to research the signal compatibility and code phase measurements of BOC system signal. Research shows that BOC(10,5) has many characteristics about wideband, noise and multipath interference performance, compatibility, and low code measurement,and it was an irreplaceable advantage and role in the modern GPS satellite signals.Finally, simulation and analysis of the BPSK and BOC signal by design process, given the simulation process. Using software to receive the intermediate frequency signal for capture test,analyzing the characteristics and experimental from the time domain, the frequency and acquisition sensitivity of simulation signals. Experimental results show that BOC(10,5) signal inthe frequency band multiplexing, anti-channel noise, frequency signal capture, the code measurement errors and capture accuracy are meet the requirements of the design.