Global Navigation Satellite System is a kind of Navigation Satellite System that can provide Global

all-weather，high precision location of all-time and the timing information. The serial capture algorithm searches fora satellite spread spectrum signal sequentially at each possible code phase and doppler shift in time domain，it iseasy to implement in both the hardware and software simulation. Although serial capture algorithm has high preci-lion，but due to its larger computational cost，longer capture time，these become serious disadvantages. A serialcapture algorithm is put forward to extract at mixing front-end，based on guaranteeing the acquisition precision，thealgorithm can reduce the amount of calculation effectively，shorten the acquisition time，improve the capture effi-ciency. The simulation proofs that the proposed algorithm can capture the satellite signal effectively and ruduce thecapture time. The algorithm of this paper has strong feasibility on both the theory and practical application.