Group-blind detection with very large antenna arrays in the presence of pilot contamination

TL;DR

This paper introduces a group-blind detection method for massive MIMO systems that leverages excess antennas to mitigate pilot contamination, significantly improving SINR in interference-limited scenarios.

Contribution

The paper proposes a novel group-blind detector that uses excess antennas to reduce pilot contamination effects during uplink data transmission in massive MIMO systems.

Findings

SINR can be doubled with group-blind detection in interference-limited scenarios.

Analytical derivation of asymptotic SINR confirms the effectiveness of the proposed method.

Simulation results validate the theoretical improvements over traditional detection methods.

Abstract

Massive MIMO is, in general, severely affected by pilot contamination. As opposed to traditional detectors, we propose a group-blind detector that takes into account the presence of pilot contamination. While sticking to the traditional structure of the training phase, where orthogonal pilot sequences are reused, we use the excess antennas at each base station to partially remove interference during the uplink data transmission phase. We analytically derive the asymptotic SINR achievable with group-blind detection, and confirm our findings by simulations. We show, in particular, that in an interference-limited scenario with one dominant interfering cell, the SINR can be doubled compared to non-group-blind detection.