Abstract: Based on PN(pseudo noise) code auto-correlation property and cubic-spline interpolation fitting method,a new signal fast acquisition algorithm of GPS(golbal position system) is proposed.First,coarse C/A code phase is obtained by low-frequency sample sequence using circular correlation method.Then,based on coarse C/A code phase,partial high-frequency sample sequence for secondary acquisition is obtained.PN code auto-correlation property is used to get fine C/A code phase.Furthermore,cubic-spline interpolation method is used to process correlation peak and neighboring value to improve the measurement precision of C/A code phase.Simulation results show that the proposed algorithm has advantages of high precision and low computation.