General analysis of multiuser MIMO systems with regularized zero-forcing precoding under spatially correlated Rayleigh fading channels

摘要

A general framework for the analysis of expected per-user signal-to-interference-plus-noise-ratio (SINR) of a multiuser multiple-input-multiple-output system is presented. Our analysis assumes spatially correlated Rayleigh fading channels with regularized zero-forcing precoding on the downlink. Unlike previous works, our analytical expressions are averaged over the eigenvalue densities of the complex Wishart distributed channel correlation matrix. To aid the derivation of the expected per-user SINR, we derive a closed-form expression for the joint density of two arbitrary eigenvalues of the complex Wishart matrix. In the high signal-to-noise-ratio (SNR) regime, with zero-forcing precoding, we derive analytical expressions to approximate the instantaneous per-user SNR and show that it is approximately gamma distributed. The generality of the approximations is validated with numerical results over a wide range of system dimensions, spatial correlation and SNR levels.