Abstract:  With the development of GNSS and Internet of things technology, multi mode receiver has been used more and more widely. As the first step of signal processing in the receiver,  signal acquisition ability directly affects the overall performance of the receiver. In this paper, an optimization method is proposed to solve the problems such as poor FFT algorithm compatibility, long operation time and large resource occupation encountered in the design of the capture module of multi mode receiver. The method is designed by adding intercept operation, module reuse and pipeline structure to solve the above problems. The simulation analysis and hardware implementation show that this method has obvious improvement in resource occupation, operation time and compatibility.