volume | PIER Journals

Abstract

In this paper, a compact multiple-input multiple-output (MIMO) antenna is proposed for unmanned aerial vehicles (UAVs). By simultaneously exciting common mode (CM) and differential mode (DM) from a T-shaped slot, wideband coverage is achieved. Four such slot antennas are used to form a four-antenna module operating in the N79 band (4.4-5.0 GHz). The size of the four-antenna module is merely 43 × 8 mm², demonstrating excellent miniaturization and integration. The dominant coupling between adjacent elements occurs through currents of the same mode. When CM and DM currents coexist, partial cancellation of coupled currents at the feed point enables high isolation without ex-ternal decoupling structures. Two modules are symmetrically positioned along the longer edges of the frame, forming an 8-element MIMO antenna. The antenna achieves isolation greater than 11 dB and an envelope correlation coefficient (ECC) below 0.04. The measured total efficiency is better than 52%, with an average of 56%. Featuring compact footprint, zero-clearance constraint and high isola-tion, the proposed antenna is a promising candidate for 5G UAVs.

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Dr. Yangyang Guan

Dr. Peng Zhang

Mr. Xulong Wang

Dr. Jie Bai