Abstract: In a highly dynamic environment, the satellite signal received by the receiver has a large doppler shift. The realization of positioning, navigation, timing and other functions puts forward higher requirements for the acquisition algorithm. The paper uses an improved PMF-FFT acquisition algorithm, as the traditional time-domain serial acquisition algorithm and the FFT-based parallel code phase acquisition algorithms have high time complexity, resulting in slower acquiring speed. While the receiver captures the signal, the 2 ms input signal and the local carrier signal are added in the way of xorring to 64 partially matched filters, and the output data is added with hamming window function to perform 64-point FFT operation. After taking the modulo of the result, it is compared with the threshold value, and the acquisition is judged to be successful if it is higher than the threshold value. The experimental simulation results show that the method can complete the rapid capture of the highly dynamic Beidou B1 I signal accurately.