The design and efficient structure of all phase filter banks for multi-carrier modulation

In this paper, a novel all phase DFT filter bank (APFB) for multi-carrier modulation is presented and the efficient implementation structure is derived. A narrowband APDFT prototype filter exhibits higher stop attenuation and an M-band APFB with the strict power complementarities can be easily achieved by designing the frequency response vectors. The impulse response of the proposed APFB is also real and symmetric. For a modulation system with the sub-channel number M, the overlapped factor 2q and the symbol period for sub channel T₀, the multiplication processing unit (MPU) amount is (3Mlog₂M+2qMlog₂2q+6qM+M+1)/T₀ per second for the transmitter and (2qM+2qMlog₂2qM+4M-4)/T₀ per second for the receiver with the efficient structure whereas the MPU amount is (4qM³-M²)/T₀ per second for those with the direct realization structure. The comparison shows that the proposed structure possesses the advantage of much higher computational efficiency than the direct realization structure.