LIMITED FEEDBACK SCHEME BASED ON ADAPTIVE CODEBOOK FOR SPATIALLY AND TEMPORALLY CORRELATED MIMO CHANNELS

In this paper, the problem of limited feedback for spatially and temporally correlated multiple input multiple output (MIMO) channels is addressed. We analyze the impact on the channel vectors made by the spatial and temporal correlation with the concept that the channel vectors fall on the spherical cap. We develop the probability that the channel vectors are distributed axisymmetrically on the hypersphere and obtain the adaptive codebook design criteria. A novel limited feedback scheme based on adaptive codebook is proposed following the principle that the codebook should be efficiently adapted to the underlying long term channel statistics. Simulation results will be provided to demonstrate that the proposed limited feedback scheme outperforms the fixed codebook for spatially and temporally correlated MIMO channels.