Multiuser blind channel estimation and spatial channel pre-equalization

In this paper, we study two of the fundamental operations of a TDD smart antenna system, namely, the uplink channel and sequence identification and downlink selective transmission. For uplink, our focus is on the development of a blind estimation algorithm which is capable of resolving a multiuser system without the use of training sequence or any input statistics. For downlink, we propose a spatial channel pre-equalization scheme which simultaneously eliminates the intersymbol interference (ISI) and the co-channel interference (CCI) for all users using FIR filters. Both algorithms were validated by RF experiments using the smart antenna testbed developed in the University of Texas at Austin.