Aiming at the disadvantage of the conventional phase-coherent accumulation method for uniform acceleration of target energy accumulation, four typical phase-coherent accumulation methods are selected and simulated. The characteristics of different transformation accumulation methods for uniform acceleration target Linear Frequency Modulated(LFM) signal are studied, as well as the differences of energy accumulation in different time-frequency analysis methods by pulse number. The result shows Fractional Fourier Transform(FRFT) can suppress noise effectively, estimate acceleration directly，and has good performance in the time-frequency clustering. The performance of coherent integration is improved further with increase of pulse number within limits.