Design of M-band complex-valued filter banks for multicarrier transmission over multipath wireless channels

The orthogonal M-band complex-valued filter banks have more flexibility in terms of frequency response. In this paper, a new general design method for orthogonal M-band complex-valued filter banks is presented for multicarrier (MC) transmission to reduce intersymbol and interchannel interference (ISI and ICI). The design includes three procedures. First, a parameterization method is used to design the baseband scaling filter. Then the M-1 band wavelet filters are deduced based on the scaling filter by a Gram-Schmidt algorithm. Thirdly, a numerical optimization method is developed to determine the free parameters and coefficients of the filter banks based on an objective to minimize the intersymbol and interchannel interference power for a multipath wireless channel. Simulation results demonstrate that the MC system based on the designed M-band complex-valued filter banks has superior performance to that of discrete Fourier transform (DFT) based orthogonal frequency division multiplexing (OFDM) and discrete wavelet multitone (DWMT) in terms of the interference power over a multipath channel.