Networked MIMO with Clustered Linear Precoding

TL;DR

This paper proposes a clustered coordination strategy for cellular MIMO networks that enhances sum rate and reduces interference through intra- and inter-cluster cooperation, using multi-cell block diagonalization and optimized precoding.

Contribution

It introduces a novel clustered coordination approach with specific precoding algorithms, balancing performance and complexity, and demonstrates significant sum rate improvements with small cluster sizes.

Findings

Small cluster size (~7 cells) achieves most sum rate gains.

Proposed algorithms effectively reduce interference.

Coordination improves cellular MIMO network performance.

Abstract

A clustered base transceiver station (BTS) coordination strategy is proposed for a large cellular MIMO network, which includes full intra-cluster coordination to enhance the sum rate and limited inter-cluster coordination to reduce interference for the cluster edge users. Multi-cell block diagonalization is used to coordinate the transmissions across multiple BTSs in the same cluster. To satisfy per-BTS power constraints, three combined precoder and power allocation algorithms are proposed with different performance and complexity tradeoffs. For inter-cluster coordination, the coordination area is chosen to balance fairness for edge users and the achievable sum rate. It is shown that a small cluster size (about 7 cells) is sufficient to obtain most of the sum rate benefits from clustered coordination while greatly relieving channel feedback requirement. Simulations show that the proposed coordination strategy efficiently reduces interference and provides a considerable sum rate gain for cellular MIMO networks.