MIMO Antenna Fundamentals and Characterization Methods

Summary

In today's telecommunications systems, multiple‐input multiple‐output (MIMO) techniques are employed widely. MIMO technology is a key enabler for the fifth‐generation (5G) and next‐generation communications. MIMO antennas benefit from multipath scenarios. Thus, only using conventional antenna metrics is insufficient to characterize its performance. This chapter first briefly introduces performance metrics for conventional antennas, such as gain, efficiency, and polarization. Then, diversity gain and MIMO capacity – two widely used performance metrics for describing MIMO antennas – are introduced. Additionally, several metrics related to MIMO capacity and diversity gain – including isolation, correlation coefficient, total active reflection coefficient (TARC), mean effective gain (MEG), and power‐combining techniques – are covered in detail. Finally, we discuss S‐parameter‐based and port‐level MIMO antenna characterization techniques. Furthermore, methods for evaluating MIMO capacity and diversity gain using anechoic and reverberation chambers are also presented.