Combining the advantages of partial matched filter (PMF) and fast Fourier transform ( FFT),an improved fast acquisition method for GPS C/A code is proposed.According to PMF-FFT acquisition architecture,the greater the number of PMF will bring out the more slowly amplitude decreasing of the amplitude-frequency response,the smaller scale of the corresponding PMF,and the larger computation of the FFT.In order to compensate the frequency spectrum attenuation caused by spectrum leakage and fence effect,adding window function to PMF-FFT is presented.Through comparing the influences to the acquisition performance based on rectangular,Hamming,Blackman and Rife-Vincent ( Ⅲ ) window functions,an improved Rife-Vincent Ⅲ windowing algorithm is recommended for the fast acquisition based on PMF-FFT.