An efficient FPGA-based implementation of fractional Fourier transform algorithm

In this paper, we present an efficient FPGA implementation method of fractional Fourier transform (FrFT) algorithm. Firstly, a polyphase implementation of the FrFT computation algorithm base on the theory of multirate signal processing and filter banks is proposed. This polyphase implementation costs less computations and its parallel structure is suitable for FPGA realization. Then we present one computational method, which improve the resolution on any portion of fractional spectrum. Some realization details, such as the parity restrictions of signal length, special interval for transform order, interpolation filter, continuous frame computation and continuous order computation are also investigated. Finally, the efficiency of the novel method is verified by FPGA implementation results.