Multiport broadband 5G MIMO antenna with very high isolation

Abstract

This paper presents a new unidirectional radiating structure with 4 independent radiation patterns, with an isolation of more than 24 dB, and with a bandwidth of 20 %, oriented for use in 5G indoor MIMO base stations. The element can be used as a building block for arrays with a number of antennas of 4x4 or more. The radiating elements are triangular cavities derived from a square cavity with the TMz 11 mode. The 4-port antenna has a very low profile, with a height of 5 mm and the dimensions of the ground plane are less than one wavelength.