Compact $2 \times 2$ MIMO Mm-Wave Antenna with Hybrid-Stub-Loaded Elliptical Slot for V-Band Wireless Communication Systems

A novel millimeter-wave (mm-wave) multipleinput multiple-output (MIMO) antenna is proposed for advanced 5 G and beyond- 5 G communication systems, covering key frequency bands in the V-band (<tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$48.1 \text{GHz}, 54.3 \text{GHz}, 56.5$</tex> GHz, 65.2 GHz, and 71.1 GHz). The antenna employs a hybrid-stub-loaded elliptical slot radiator, coupled with V-shaped directional elements, to achieve stable radiation patterns and high gain. A <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$2 \times 2$</tex> MIMO is implemented, where the elements of the antenna are orthogonally positioned to each other to minimize mutual coupling and enhance spatial diversity. The compact, planar configuration, designed on a <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$10 \text{mm} \times 10 \text{mm}$</tex> Neltec substrate with a dielectric constant of 3.2, facilitates seamless integration into various wireless devices. simulations and optimization techniques are conducted to evaluate key performance metrics, including return loss, radiation pattern, gain, envelope correlation coefficient (ECC), and isolation between antenna elements. The proposed design demonstrates high radiation efficiency and excellent isolation, making it a strong candidate for high-data-rate, low-latency 5G and future wireless communication applications.