Unitary isotropically distributed inputs are not capacity-achieving for large-MIMO fading channels
Paper i proceeding, 2012

We analyze the capacity of Rayleigh block-fading multiple-input multiple-output (MIMO) channels in the noncoherent setting and prove that unitary space-time modulation (USTM) is not capacity-achieving when the total number of antennas exceeds the coherence time of the fading channel. This situation is relevant for MIMO systems with large antenna arrays (large-MIMO systems). Our result settles a conjecture by Zheng & Tse (2002) in the affirmative. The capacity-achieving input signal, which we refer to as Beta-variate space-time modulation (BSTM), turns out to be the product of a unitary isotropically distributed random matrix, and a diagonal matrix whose nonzero entries are distributed as the eigenvalues of a Beta-distributed random matrix of appropriate size. Numerical results illustrate that using BSTM instead of USTM in large-MIMO systems yields a rate gain as large as 13% for SNR values of practical interest.

Författare

Wei Yang

Chalmers, Signaler och system, Kommunikations- och antennsystem, Kommunikationssystem

Giuseppe Durisi

Chalmers, Signaler och system, Kommunikations- och antennsystem, Kommunikationssystem

Erwin Riegler

Technische Universität Wien

2012 IEEE International Symposium on Information Theory, ISIT 2012. Cambridge, MA,1 - 6 July 2012

1717-1721 6283571

Styrkeområden

Informations- och kommunikationsteknik

Ämneskategorier

Telekommunikation

DOI

10.1109/ISIT.2012.6283571

ISBN

978-146732579-0

Mer information

Senast uppdaterat

2018-03-02