Dielectric resonator based MIMO antenna system enabling millimetre‐wave mobile devices

In this study, a millimetre‐wave dielectric resonator (DR)‐based multiple‐input–multiple‐output (MIMO) antenna system based on two linear arrays is presented. Each array that represents a single MIMO antenna consists of four cylindrical DR antenna (cDRA) elements operating at 30 GHz with a bandwidth of at least 1 GHz. Each array is designed with a fixed beam direction which is tilted to provide low field correlation. A passive microstrip‐based feed network was designed to achieve this beam tilting enabling suitable magnitude and phase excitation of the individual cDRAs for radiation. The complete antenna system was designed on a two‐layer substrate occupying 48 mm × 21 mm. Excellent field correlation values were measured (below 0.002) across the band of operation while peak gains were >7 dBi. High radiation efficiency is obtained. The proposed design approach for beam tilting, which enables MIMO operation, may also be useful for other compact implementations to support 5G communications.