An INS-Aided GPS fast acquisition algorithm for high dynamic applications

GPS signal acquisition is the prerequisite for signal tracking and navigation message demodulation. In a high dynamic environment, the high-speed movement between GPS satellite and receiver will generate a large Doppler frequency shift, which makes it difficult to acquire GPS signal. This paper proposed a new INS-Aided parallel code phase acquisition algorithm for high dynamic applications. For frequency search, the algorithm utilizes INS auxiliary information and GPS almanac data to estimate Doppler frequency shift and narrow down the search range of frequency. For code phase search, the algorithm adopts the parallel code phase searching method to reduce the time of code phase search and improve the overall acquisition speed. The proposed algorithm was validated by a semi-physical simulation experiment and the result shown that the proposed algorithm could improve the acquisition speed and the performance of GPS receiver under high dynamic environment remarkably.