A 5G Enabled Shared-Aperture, Dual-Band, in-Rim Antenna System for Wireless Handsets

Abstract

In this work, we present a shared aperture (SA), dual-band in metal-rim antenna system targeting the sub-6GHz and millimeter-wave (mm-wave) bands of the 5G wireless standard. The antenna system consists of a SA cactus-shaped slot engraved on the side of standard mobile terminal rim that hosts a microwave radiating structure covering the sub-6 GHz bands as well as a 4-element slot based connected antenna array (SB-CAA) covering the mm-wave bands. This provides a compact sized solution for multiband operation within these bands. The CAA has beam forming capabilities where the beam can be steered between +/- 30 degrees with acceptable gain and side lobe levels (SLL). A single 4-element slot based in-rim SB-CAA is also proposed that covered more than 6 GHz of frequency bandwidth (25.5-32 GHz) with a total efficiency exceeding 85% and realized averaged gain of 8.2 dBi over the bands covered. The SA cactus antenna structure had a bandwidth exceeding 3.5 GHz with total efficiency exceeding 75% and an average realized gain of 8 dBi between 26.5 - 30 GHz. For the microwave band covered (3.45-3.56 GHz) by this SA cactus antenna, a bandwidth of 140 MHz, efficiency of 90% with 2.5 dBi of measured gain were achieved.