Non-causal delayless subband adaptive equalizer

In wireless communication, multiple versions of the transmitted signals arrive at the receiver with different attenuations and time delays. Thus, an equalizer with long filter is required at the receiver to reverse the multipath effects. In this paper, a new non-causal delayless subband equalizer structure is proposed to reduce the computational complexity of the equalizer and to improve the channel tracking capability. This structure avoids the additional delays usually associated with the subband schemes. A design method is formulated to minimize the aliasing effect of the filter bank in the subbands. The significance of employing a non-causal equalizer is also emphasized. Simulation results show that the performance of the new structure is significantly improved by using the design method. Moreover, the complexity of the new subband equalizer is a fraction of the equivalent fullband at the expense of small degradation in the performance.