Perfect reconstruction DFT modulated oversampled filter bank transceivers

Abstract

This paper proposes a novel method for the design of perfect reconstruction (PR), discrete Fourier transform (DFT) modulated oversampled filter banks (FB) for application in multi-carrier transceiver systems. The PR property is guaranteed by enforcing a paraunitary constraint on the polyphase matrix of the transmit or receive sub-systems. The desired polyphase matrix is obtained via embedding of lower dimensional paraunitary building blocks, each expressed in terms of a limited set of design parameters through a factorization based on Givens rotations. These parameters are adjusted to minimize the stop-band energy of the subband filters and thus improve their spectral containment. The performance of the proposed FB is investigated in a multi-carrier transceiver application, where it is compared with OFDM and other recently proposed FB structures. Numerical results show that the proposed approach can lead to significant reduction in the bit error rate (BER), as compared to the benchmark approaches, when used in the presence of narrowband interference or frequency offset.