Energy- and Cost-Efficient Mobile Communication Using Multi-Cell MIMO and Relaying

In this paper, relaying and multi-cell MIMO transmission are investigated as approaches for improving resource reuse and more flexible organization of cellular networks. The analysis focuses on approaches for future cellular systems, which jointly exploit relaying and multi-cell MIMO transmission. Possible candidate approaches are identified, simplified for practical applications and evaluated using a system-level model from the European research project WINNER. Their achievable throughput is analyzed under practical constraints using three different normalization approaches: cost-normalization, energy-normalization, and joint cost-energy-normalization. It can be shown that the combined approach of relaying and multi-cell MIMO provides significant gains for the uplink communication. The selected approach exploits cooperative multi-cell MIMO processing between base stations and relay nodes, and uses a resource coordination technique on the links between relay nodes and user terminals. If a relay-based deployment is subject to a cost- and energy-normalization, multi-cell MIMO outperforms relaying with respect to achievable downlink throughput.