Spectral Efficiency Analysis of Multi-Cell Massive MIMO Systems with Ricean Fading

TL;DR

This paper derives closed-form and asymptotic expressions for spectral efficiency in multi-cell massive MIMO systems with Ricean fading, revealing conditions under which pilot contamination can be eliminated.

Contribution

It provides novel exact asymptotic formulas for SINR in Ricean fading environments and analyzes pilot contamination removal with MMSE estimation in high M and K regimes.

Findings

Closed-form SINR expressions for any M and Ricean K-factors.

Asymptotic SINR formulas in high M and K regimes.

Pilot contamination is eliminated when both M and K are infinite.

Abstract

This paper investigates the spectral efficiency of multi-cell massive multiple-input multiple-output systems with Ricean fading that utilize the linear maximal-ratio combining detector. We firstly present closed-form expressions for the effective signal-to-interference-plus-noise ratio (SINR) with the least squares and minimum mean squared error (MMSE) estimation methods, respectively, which apply for any number of base-station antennas $M$ and any Ricean $K$-factor. Also, the obtained results can be particularized in Rayleigh fading conditions when the Ricean $K$-factor is equal to zero. In the following, novel exact asymptotic expressions of the effective SINR are derived in the high $M$ and high Ricean $K$-factor regimes. The corresponding analysis shows that pilot contamination is removed by the MMSE estimator when we consider both infinite $M$ and infinite Ricean $K$-factor, while the pilot contamination phenomenon persists for the rest of cases. All the theoretical results are verified via Monte-Carlo simulations.