Date Added: Dec 2009
The authors consider the problem of Channel State Information (CSI) transmission on a fast feedback link for a Multiuser-MIMO OFDM system. They compare codebook based feedback with analog based feedback and propose a new compressed analog feedback suitable for correlated antennas that provides excellent tradeoff between uplink overhead and downlink throughput. They show via bi-directional simulation results the reliability of analog feedback in general and its advantage over codebook based feedback. The idea of analog feedback was proposed in the past in order to facilitate Closed Loop (CL)-MIMO in FDD systems.