Study on technique for GPS if signal simulation

In order to solve the difficulty of simulating the satellite signal with the complexity of the structure of hardware signal source and the variability of the environment, an IF signal model architecture is used in this paper. By producing navigation message and observational data with the mathematical simulation system offline, these data are modulated by the pseudo-random code and the IF carrier to produce the IF analog signal. Then the IF analog signal becomes the IF digital signal after further sampled and Quantify. The GPS IF signal is produced by the use of Matlab simulation and then is further located though the receiver. Simulation result shows that receiver positioning result is basically the same as observational data which is generated by the mathematical simulation system, proving that the scheme is of good reason. The IF signal model can effectively solve the disadvantage of hardware simulation equipment and thus a class of problems including High input and Low output which hardware simulation attributes are solved.