Average and Worst-case Analysis of MIMO Beamforming Loss due to Hardware Impairments

TL;DR

This paper analyzes how hardware imperfections like gain mismatches and spacing deviations affect MIMO beamforming, revealing that worst-case scenarios can cause significant performance loss while average performance remains relatively stable.

Contribution

It provides analytical expressions for both worst-case and average-case beamforming performance degradation due to hardware impairments in MIMO systems.

Findings

Worst-case impairments cause substantial SNR loss.

Average-case performance degradation is limited.

Results offer insights into MIMO robustness under hardware imperfections.

Abstract

In this paper, we investigate the impact of hardware impairments in antenna arrays on the beamforming performance of multi-input multi-output (MIMO) communication systems. We consider two types of imperfections: per-element gain mismatches and inter-element spacing deviations. We analytically determine the impairment configurations that result in the worst-case degradation. In addition, the analytical expression of the average-case performance is also derived for comparison. Simulation and theoretical results show that the average SNR degradation remains relatively limited, whereas the worst-case scenarios can exhibit substantially higher losses. These findings provide clear insight into the robustness limits of MIMO systems under practical hardware imperfections.