Low-Power High-Speed Radix-2 DIT FFT Suitable for AAC/DRA Audio Decoding

In this paper, an implementation of low-power, high-speed radix-2 DIT (decimation-in-time) FFT suitable for AAC/DRA audio decoding is presented. For low-power and high-speed considerations, two methods are adopted: adding cache to ROM (ROM-cache) and proposing a new butterfly (AI-Butterfly). Simulations in Matlab have verified the correctness of this implementation. The comparisons between the proposed FFT implementation and other FFTs prove that the proposed FFT has a big reduction in power consumption, and only 19% slower than the fastest pipeline FFT, but 30% faster than cached-FFT and 61% faster than original radix-2 DIT FFT.