Adaptive array processing for multipath fading mitigation via exploitationof filter banks

In this paper, we propose subband adaptive array processing for mitigation of both intersymbol interference (ISI) and cochannel interference (CCI) in digital mobile communications. Subband adaptive array processing employs fi lter banks in a front end to an adaptive array receiver. By decomposing the signals into a set of subband signals, the analysis Biters enhance the cor relation of multipath rays in each subband. This enhancement is blind in th e sense that no a priori knowledge of the temporal characteristics or spati al signatures of arriving signals is required. With the increased coherence , the desired signal can be effectively equalized by subsequent spatial pro cessing. Further, the CCI signals and their multipaths can be suppressed wi th fewer degrees of freedom, The effects of quadrature mirror filter and di screte Fourier transform Biter banks on multipath correlation are delineate d.