In the last decade, there have been several approaches on the topic of computing discrete fractional Fourier transform (DFrFT). The purpose of this work is to provide a unified approach to improve the computation of DFrFT. Based on results by Ozaktas et a1., a more general multirate filter structure is developed for the improvement of computing DFrFT. With introduction of block-input--block-output technique, a specific multirate filtering system can be converted to an equivalent linear time-invariant (LTI) multi-input--multi-output (MlMO) system. Other DFrFT algorithms based on matrix--vector multiplication can also be implemented by the similar structure. Therefore, a unified computation framework is developed for the multirate implementation of the DFrFT via the proposed MIMO system. Finally, for the implementation of DFrFT system, a corresponding fractional Fourier filter bank (FrFB) is also constructed as an extension of the conventional discrete Fourier transform (DFT) filter bank system.
展开▼
