Achievable Sum Rate of MIMO MMSE Recievers: A General Analytic Framework

TL;DR

This paper introduces a new analytic framework linking the achievable sum rate of MIMO MMSE receivers to ergodic mutual information, enabling easier analysis and deriving new closed-form expressions for various channel scenarios.

Contribution

The paper presents a novel analytical framework connecting MIMO MMSE sum rate with ergodic mutual information, facilitating new exact and asymptotic expressions for different channel models.

Findings

Derived new closed-form expressions for Rayleigh and Rician channels.

Provided asymptotic analysis at high and low SNR regimes.

Unveiled key performance insights of MIMO MMSE receivers.

Abstract

This paper investigates the achievable sum rate of multiple-input multiple-output (MIMO) wireless systems employing linear minimum mean-squared error (MMSE) receivers. We present a new analytic framework which unveils an interesting connection between the achievable sum rate with MMSE receivers and the ergodic mutual information achieved with optimal receivers. This simple but powerful result enables the vast prior literature on ergodic MIMO mutual information to be directly applied to the analysis of MMSE receivers. The framework is particularized to various Rayleigh and Rician channel scenarios to yield new exact closed-form expressions for the achievable sum rate, as well as simplified expressions in the asymptotic regimes of high and low signal to noise ratios. These expressions lead to the discovery of key insights into the performance of MIMO MMSE receivers under practical channel conditions.