Research On Generation And Processing Technology Of High Precision Pseudorange Signal For Satellite Navigation Simulator

With the development and wide application of satellite navigation technology,the research of satellite navigation signal simulator technology has received more and more attention.The satellite navigation signal simulator is a high-precision standard signal source.The dynamic characteristics of the carrier and the effects of factors such as the ionosphere and troposphere on the satellite signal can be simulated using a satellite navigation simulator.The satellite navigation signal simulator can simulate the navigation signals of the satellites received by the receiver,thereby providing a simulation environment for the development and testing of the navigation receiver.The paper focuses on the processs and generation of satellite navigation analog signals and the realization of high-precision pseudorange signals.The main work includes:1.Part of the algorithm for high-precision pseudorange signal generation processing is designed.Aiming at the delay processing of high-precision clock signal,the clock front-end jitter error model is established,and the clock leading edge jitter error is analyzed.The method of generating high-precision clock signal based on time-amplitude modulation is studied,and FPGA programming is implemented.An improved DDS micro-Doppler signal frequency offset processing algorithm is presented,and FPGA programming debugging is carried out.2.The IF signal processing scheme of GNSS navigation signal simulator based on interpolation filtering structure is designed.The signal processing method of interpolation filtering is discussed.The FARROW structure based on fractional multiplier is designed to complete the FPGA-based four Partial IF signal processing designed for the satellite navigation system simulator.3.A test platform is bulit.The hardware receiver is used to test and verify the navigation signal based on the interpolation filter structure,and the positioning result is obtained and compared with the theory to verify the feasibility of the navigation signal.The Chipscope is used to capture the FPGA signal,and the oscilloscope pair is used to verify the test.The feasibility of the high-precision pseudorange signal generation algorithm is verified.