Optimized data sharing in multicell MIMO with finite backhaul capacity

TL;DR

This paper proposes an optimized rate splitting strategy for multicell MIMO systems with limited backhaul capacity, balancing data sharing and interference management to improve overall network performance.

Contribution

It introduces a novel rate splitting approach with optimal beamforming for finite backhaul capacity, enabling adaptive data sharing based on interference levels.

Findings

Achieves a trade-off between data sharing and interference mitigation.

Derives the achievable rate region for the proposed scheme.

Shows how backhaul capacity influences data sharing decisions.

Abstract

This paper addresses cooperation in a multicell environment where base stations (BSs) wish to jointly serve multiple users, under a constrained-capacity backhaul. We point out that for finite backhaul capacity a trade-off between sharing user data, which allows for full MIMO cooperation, and not doing so, which reduces the setup to an interference channel but also requires less overhead, emerges. We optimize this trade-off by formulating a rate splitting approach in which non-shared data (private to each transmitter) and shared data are superposed. We derive the corresponding achievable rate region and obtain the optimal beamforming design for both shared and private symbols. We show how the capacity of the backhaul can be used to determine how much of the user data is worth sharing across multiple BSs, particularly depending on how strong the interference is.