Limited Feedback for Temporally Correlated Channels
In the limited feedback literature, the block fading assumption is commonly made to simplify analysis. Such assumption for the channel is pessimistic since channel temporal correlation often
exists and can be used for reducing feedback rates. On the other hand, the block fading assumption hinders the
analysis of feedback delay, which exists in a practical system due
to sources such as signal processing, propagation and protocol
delays. The drawbacks of block fading assumption motivated us to develop a framework for analyzing a limited feedback system for a temporally correlated channel. In particular, this frame work addresses the feedback rate
and delay. The novelty of the framework
lies in the modeling of quantized CSI using a Markov chain (see figure) and its
use in deriving a set of analytical results. Specifically, the
feedback rate, the feedback compression method, the downlink
capacity with feedback delay, and the exponential decay rate of the
capacity gain caused by feedback delay are analyzed. The proposed
framework is useful for computing the required feedback rate and
evaluating the impact of feedback delay. This framework is
applicable for any typical limited feedback system having a
temporally-correlated channel and employing adaptive transmission
such as beamforming, precoding and adaptive modulation.
Related Publications and Preprints:
[1] K. Huang, B. Mondal, R. W. Heath, Jr., and J. G. Andrews, ``Limited Feedback for Temporally-Correlated Channels: Feedback Rate and Delay,'' submitted to the IEEE Trans. on Info. Theory, March 2006. Also available on ArXiv.
[2] K. Huang, B. Mondal, R. W. Heath, Jr., and J. G. Andrews, ``Effect of Feedback Delay on Multi-Antenna Limited Feedback for Temporally-Correlated Channels,'' accepted to Proc. of IEEE Global Telecommunications Conf., Nov. 27 - Dec. 1, San Francisco, CA, USA.
[3] K. Huang, B. Mondal, R. W. Heath, Jr., and J. G. Andrews, ``Multi-Antenna Limited Feedback for Temporally-Correlated Channels: Feedback Compression,'' accepted to Proc. of IEEE Global Telecommunications Conf., Nov. 27 - Dec. 1, San Francisco, CA, USA.
[4] K. Huang, B. Mondal, R. W. Heath, Jr., and J. G. Andrews, ``Markov Models for Limited Feedback MIMO Systems", Proc. of the IEEE Int. Conf. on Acoustics, Speech, and Signal Proc., vol. 4, pp. IV-9-IV-12, Toulouse, France, May 14-19, 2006.
