Performance analysis of subband adaptive arrays in multipath propagation environment

This paper proposes the subband adaptive array processing technique, which is used to mitigate both inter-symbol interference (ISI) and cochannel interference (CCI) in digital mobile communications. The analysis filters enhance the signal coherence of multipath rays in each subband. This enhancement is blind in the sense that no a priori knowledge of the arriving signals is required. With the increased coherence, both the desired and the CCI signals are effectively equalized by the subsequent spatial processing. Therefore, the effect of multipath fading associated with the desired signal can be greatly reduced. Additionally, the CCI signals and their multipaths can be suppressed with fewer array degrees-of-freedom.