Capacity-achieving input covariance for single-user multi-antenna channels

We characterize the capacity-achieving input covariance for multi-antenna channels known instantaneously at the receiver and in distribution at the transmitter. Our characterization, valid for arbitrary numbers of antennas, encompasses both the eigenvectors and the eigenvalues. The eigenvectors are...

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Bibliographic Details
Authors: Tulino, Antonia M., Lozano Solsona, Angel, Verdú, Sergio
Format: article
Status:Versión aceptada para publicación
Publication Date:2006
Country:España
Institution:Varias* (Consorci de Biblioteques Universitáries de Catalunya, Centre de Serveis Científics i Acadèmics de Catalunya)
Repository:Recercat. Dipósit de la Recerca de Catalunya
OAI Identifier:oai:recercat.cat:10230/16125
Online Access:http://hdl.handle.net/10230/16125
http://dx.doi.org/10.1109/TWC.2006.1611096
Access Level:Open access
Keyword:Ràdio -- Antenes
Tractament del senyal
Channel capacity
Multi-antenna arrays
Input optimization
Fading channels
Antenna correlation
Ricean channels
Keyhole channels
Channel-state Information
Description
Summary:We characterize the capacity-achieving input covariance for multi-antenna channels known instantaneously at the receiver and in distribution at the transmitter. Our characterization, valid for arbitrary numbers of antennas, encompasses both the eigenvectors and the eigenvalues. The eigenvectors are found for zero-mean channels with arbitrary fading profiles and a wide range of correlation and keyhole structures. For the eigenvalues, in turn, we present necessary and sufficient conditions as well as an iterative algorithm that exhibits remarkable properties: universal applicability, robustness and rapid convergence. In addition, we identify channel structures for which an isotropic input achieves capacity.