An efficient FFT-mapping method based on cache optimization

Fast Fourier Transform (FFT) is an important technology in real-time signal processing system, which means the efficiency of FFT algorithm mapping to hardware system has very important significance. At first, we aim at the FFT execution process on processor. And then analyze the memory access process based on cache mechanism, and get that the cache hit directly affects FFT execution time. Hence, an efficient mapping method is come up with, which splits long FFT into multiple segments to make sure every segment is shorter than the cache capacity. Accordingly, the cache hit rate will be improved, correspondingly, the execution efficiency will be better finally. In the end, the new method is experimented on the ADI´s TS201 digital signal processor, and the result shows that the execution time of FFT is improved greatly.