Abstract: A novel method for the long term signal integral detection of weak targets is presented. The signal is divided into several frames in time domain. In each frame, the HAF spectrum is filtered with certain threshold to preserve the object information and eliminate the interference and noise. And then all frames are accumulated. Simulation results show that the method can integrate the signal and enhance available energy effectively, which can achieve the similar detection result to HAF, with 1/4 or 1/8 of quantity of the memory.