volume | PIER Journals

Abstract

This article presents a compact highly isolated two-port ultra-wideband (UWB) multiple-input multiple-output (MIMO) antenna with triple band suppression features. The antenna measures 25 × 39 mm² and comprises two orthogonally arranged microstrip-fed square radiators to achieve high inter-element isolation. A T-shaped and L-shaped stubs were incorporated into the ground plane to enhance isolation and broaden the impedance bandwidth. Triple band notches targeting Satellite C-band downlink (3.6-4.6 GHz), WLAN (4.9-5.5 GHz), and Wi-Fi 6E (6.1-6.7 GHz) are realized using three U-shaped slots introduced on each radiating element. The antenna's operation is analyzed through Characteristic Mode Analysis (CMA) by evaluating modal significance, characteristic angle, modal currents and mode patterns. MIMO performance is validated using key diversity metrics, including envelope correlation coefficient (ECC), diversity gain (DG), total active reflection coefficient (TARC), channel capacity loss (CCL), multiplexing efficiency (ME), and group delay. Results demonstrate an impedance bandwidth exceeding 2.9-10.6 GHz UWB range, with 90% radiation efficiency, peak gain of 6.2 dBi, ECC below 0.02, and mutual coupling under -20 dB. These outcomes confirm the efficacy of the proposed antenna in achieving compactness and high performance for UWB MIMO applications.

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Dr. Haritha Thotakura

Dr. Rajesh Gogineni

Dr. Kosuri Srinivasa Rao

Dr. Chunduri Kiran Kumar

Dr. Ramesh Babu Sadineni

Dr. Sunitha Mandava