Pipelined Radix-$2^{k}$ Feedforward FFT Architectures
Mario Garrido, Jesús Grajal, Miguel Á. Alfonso‐Sánchez, Oscar Gustafsson · IEEE Transactions on Very Large Scale Integration (VLSI) Systems · 2011
The appearance of radix-22was a milestone in the design of pipelined FFT hardware architectures. Later, radix-22was extended to radix-2k. However, radix-2kwas only proposed for single-path delay feedback (SDF) architectures, but not for feedforward ones, also called multi-path delay commutator (MDC). This paper presents the radix-2kfeedforward (MDC) FFT architectures. In feedforward architectures radix-2kcan be used for any number of parallel samples which is a power of two. Furthermore, both decimation in frequency (DIF) and decimation in time (DIT) decompositions can be used. In addition to this, the designs can achieve very high throughputs, which makes them suitable for the most demanding applications. Indeed, the proposed radix-2kfeedforward architectures require fewer hardware resources than parallel feedback ones, also called multi-path delay feedback (MDF), when several samples in parallel must be processed. As a result, the proposed radix-2kfeedforward architectures not only offer an attractive solution for current applications, but also open up a new research line on feedforward structures.