In this paper, we focus in investigating the optimal MIMO transmission and the optimal feedback strategies for MIMO link capacity when the feedback link is causal and has a capacity constraint. We show that the design of the optimal feedback scheme is identical to the design of vector quantizer (Lloyd's algorithm) with a modified distortion measure. In the general case, the optimal feedback strategy has a general form of power water-filling cascaded with beamforming matrix as well.
Published in:
Information Theory, 2003. Proceedings. IEEE International Symposium on
Date of Conference: 29 June-4 July 2003