Lens Antenna Arrays-Assisted mmWave MU-MIMO Uplink Transmission: Joint Beam Selection and Phase-Only Beamforming Design

TL;DR

This paper proposes novel joint beam selection and phase-only beamforming algorithms for lens antenna array-assisted mmWave MU-MIMO uplink systems, significantly improving sum rate performance over existing methods.

Contribution

It introduces a PDD-based iterative algorithm and a low-complexity sequential optimization approach for joint beam design in lens antenna array-assisted mmWave MU-MIMO uplink systems.

Findings

Proposed algorithms outperform state-of-the-art in sum rate.

The PDD-based method achieves higher sum rates.

Sequential optimization offers a low-complexity alternative with slight performance loss.

Abstract

This paper considers a lens antenna array-assisted millimeter wave (mmWave) multiuser multiple-input multiple-output (MU-MIMO) system. The base station's beam selection matrix and user terminals' phase-only beamformers are jointly designed with the aim of maximizing the uplink sum rate. In order to deal with the formulated mixed-integer optimization problem, a penalty dual decomposition (PDD)-based iterative algorithm is developed via capitalizing on the weighted minimum mean square error (WMMSE), block coordinate descent (BCD), and minorization-maximization (MM) techniques. Moreover, a low-complexity sequential optimization (SO)-based algorithm is proposed at the cost of a slight sum rate performance loss. Numerical results demonstrate that the proposed methods can achieve higher sum rates than state-of-the-art methods.