Frame Integrated Wideband Dual-Polarized Arrays for Mm-Wave/Sub 6-GHz Mobile Handsets and Its User Effects

Abstract

In this work, wideband dual-polarized dielectric resonator antenna (DRA) arrays are designed for 5G mobile handsets and integrated with the sub-6GHz antenna. The dielectric resonators, surrounded by concentric air holes and metal vias, are excited by two orthogonal slots and fed through microstrip lines, providing a wide bandwidth from 25.3 GHz to 29.8 GHz. A high isolation of above 40 dB is obtained between the ports of the orthogonally polarized antennas. Based on the dual-polarized DRA, two 1 × 4 arrays are built and integrated with the longer metal frames of the handset, without occupying extra space on the chassis. The scanning angle for the proposed array is from 47° to 121° for the gain of above 10 dBi, and the overall handset antennas provide a large coverage efficiency of 80% for a threshold gain of 5 dBi. User effect has also been investigated, manifesting that the horizontally polarized antennas are less influenced by the hands in both the one-hand and the two-hand data modes. Furthermore, a sub-6GHz antenna is designed with a wide operating band from 0.7 GHz to 0.94 GHz simply by making use of the shorter frames and the dual-layered DRAs, with a small ground clearance of 2 mm remained. The performances of the arrays are validated by measuring the representative antennas. The proposed antenna is a good candidate for future handsets due to its high integration with the metal frames and with the LTE antenna, its large bandwidth and large coverage in free space and different user scenarios.