MIMO Gaussian channels with arbitrary inputs: Optimal precoding and power allocation

• Type: Article in International Scientific Journal
• Date: 2010

Authors

Miguel Rodrigues (Author) FCUP; S. Verdú (Author) Other

Journal

Title: IEEE Transactions on Information Theory

Vol. 56 No. 3 (MAR 2010 )

Pages: 1070-1084

ISSN: 0018-9448

Publisher: IEEE

Indexing

ISI Web of Science

Current Contents

Scientific classification

FOS: Natural sciences > Computer and information sciences

CORDIS: Physical sciences > Computer science

Other information

Abstract (EN): In this paper, we investigate the linear precoding and power allocation policies that maximize the mutual information for general multiple-input-multiple-output (MIMO) Gaussian channels with arbitrary input distributions, by capitalizing on the relationship between mutual information and minimum mean-square error (MMSE). The optimal linear precoder satisfies a fixed-point equation as a function of the channel and the input constellation. For non-Gaussian inputs, a nondiagonal precoding matrix in general increases the information transmission rate, even for parallel noninteracting channels. Whenever precoding is precluded, the optimal power allocation policy also satisfies a fixed-point equation; we put forth a generalization of the mercury/waterfilling algorithm, previously proposed for parallel noninterfering channels, in which the mercury level accounts not only for the non-Gaussian input distributions, but also for the interference among inputs.

Language: English

Type (Professor's evaluation): Scientific

Notes: Assunto: Gaussian noise channels; minimum mean-square error (MMSE); multiple-input-multiple-output (MIMO) systems; mutual information; optimum power allocation; precoding; waterfilling.