MDFT filter banks with perfect reconstruction
Tanja Karp, Norbert J. Fliege · 2002
The Modified DFT (MDFT) polyphase filter bank has been introduced. It has been shown that this filter bank is able to cancel adjacent channel alias spectra resulting in almost perfect reconstruction. Compared to cosine modulated filter banks, the MDFT filter bank offers advantages such as linear phase analysis and synthesis filters, complex valued signal processing with a different mapping into the subbands and low propagation delays. In this paper, it is shown that the MDFT filter bank structure provides a cancellation of all odd alias spectra. Furthermore, it is demonstrated that even perfect reconstruction can be obtained by an appropriate filter design.