Design of Rectangular Antenna Array Structure for Massive MIMO

As a key technology for 5G and beyond mobile communications, massive MIMO has been implemented, tested and will be widely deployed soon. Rectangular antenna arrays, associated with 32 to 64 transceivers, are the most commonly-considered configurations for massive MIMO base stations. When testing such massive MIMOsystems in practical environments, we often obtain lower-than-expected system performance. That is to say, performance gain does not keep up with increases in hardware complexity and cost, making massive MIMO cost-inefficient in practice. We approach this problem by adapting massive MIMO antenna array design to propagation characteristics in different deployment scenarios. In this paper, we focus on rectangular array structure design with practical limits of array dimensions. The 3GPP 3D channel model is used to extract propagation properties and evaluate corresponding performance of designed arrays. Simulation results show that we gain significant performance improvements by matching array structures to propagation characteristics, as compared to using conventional array configurations. More importantly, relatively small number of antennas/transceivers and very simple processing such as matched-filtering achieve this performance gain. The results indicate a potential to boost massive MIMO performance and to some extent solve the cost-inefficiency problem, by deploying antenna arrays with suitable structures for different propagation scenarios.