Abstract: For the problem of the synchronization of Double Binary Offset Carrier (DBOC) signal can not be realized in high dynamict environment by raditional algorithm, a Discrete Polynomial phase Transformation (DPT) and a Partially Matched Filter(PMF) combines the algorithm of Fractional Fourier Transform (FRFT) are proposed. The algorithm first determines whether the received signal needs to be reduced in order by the dynamic order obtained by the DPT-FFT method, if the signal has a second-order Doppler rate of change, the signal is first degraded and then captured using the PMF-FRFT method. If the signal does not have a second-order Doppler rate of change, only with a first-order Doppler rate of change, capture directly using the PMF-FRFT method.It can be seen from the simulation results of MATLAB that the algorithm has nearly 9.5dB improved the acquisition probability compared with the DPT-PMF-FFT algorithm, and the algorithm effectively shortens the acquisition time. The algorithm can better capture the signal under high dynamics.