Multiuser MIMO Downlink Beamforming Design Based on Group Maximum SINR Filtering

TL;DR

This paper introduces an iterative beamforming and power allocation method for multiuser MIMO downlink systems using group maximum SINR filtering, improving signal quality and system performance.

Contribution

It proposes a novel joint transmit-receive beamforming and power allocation approach based on GSINR-FB, exploiting receiver diversity and simplifying power control to a linear problem.

Findings

Proposed algorithms outperform previous methods in simulations.

GSINR-FB effectively exploits receiver diversity.

Power allocation simplifies to a linear problem with improved performance.

Abstract

In this paper we aim to solve the multiuser multi-input multi-output (MIMO) downlink beamforming problem where one multi-antenna base station broadcasts data to many users. Each user is assigned multiple data streams and has multiple antennas at its receiver. Efficient solutions to the joint transmit-receive beamforming and power allocation problem based on iterative methods are proposed. We adopt the group maximum signal-to-interference-plus-noise-ratio (SINR) filter bank (GSINR-FB) as our beamformer which exploits receiver diversity through cooperation between the data streams of a user. The data streams for each user are subject to an average SINR constraint, which has many important applications in wireless communication systems and serves as a good metric to measure the quality of service (QoS). The GSINR-FB also optimizes the average SINR of its output. Based on the GSINR-FB beamformer, we find an SINR balancing structure for optimal power allocation which simplifies the complicated power allocation problem to a linear one. Simulation results verify the superiority of the proposed algorithms over previous works with approximately the same complexity.