A Comparison of Beamforming Schemes for 5G mm-Wave Small Cell Transmitters

Abstract

The combination of Massive MIMO (M-MIMO) and small cells has been selected for the fifth generation (5G) of mobile telecommunication system. But large-scale antenna arrays and extreme densification brings an important power consumption which is not compliant with the energy saving needs. Early studies have excluded fully-digital transmitters due to their high power consumption and complexity. However, the benefits of hybrid beamforming systems may not be so obvious. This paper presents an overview of 5G requirements and prospective solutions. It focuses on the base station transmitter topologies for small cells and compare their power consumption and complexity. As hybrid beamforming is suitable for small arrays covering few users, fully-digital transmitters seems compliant with larger systems to reach 5G targets.