A low profile super UWB- MIMO antenna with d-shaped for satellite communications, 5G and beyond applications.

This study presents a new compact single-layer microstrip 4-port super UWB MIMO antenna designed to operate in the frequency range of (2.5-50) GHz, achieving an impressive 320.2% impedance bandwidth. The antenna is based on a unique d-shaped geometry, specially tailored for applications in satellite communication, 5G, and Beyond, covering various bands including S-, C-, 4G LTE, sub-6 GHz, UWB, and X, ka-, k-, and ku- satellite communication bands. This aligns with Europe's efforts to harmonize by designating the 26 GHz band as a pioneer band for 5G. Additionally, 5G millimeter-wave frequencies are increasingly used in Internet of Things (IoT) applications and industrial automation. In the 5G spectrum, the midband (FR1) spans 1 GHz to 7 GHz, while the high band (FR2) covers frequencies from 24 to 52 GHz and smart wearable devices, vehicle radars, satellite communications, and smart 5G remote sensors devices. The antenna system comprises four orthogonally symmetrically placed identical radiating elements, each featuring a d-shaped patch. The metallic ground plane incorporates a curvature with a simple half-circle shape, effectively enhancing the antenna's matched bandwidth by altering the current distribution, consequently affecting the inductance and capacitance within the ground plane. A MIMO structure comprising four elements of the proposed antenna is introduced. Both simulation and experiments of the MIMO system demonstrate the antenna's impressive performance, showcasing an impedance bandwidth of 2.5 to 50 GHz, a whole-working bandwidth isolation exceeding 20 dB, an envelope correlation coefficient (ECC) below 0.013, and a significant increase in diversity gain (DG) of over 9.98 dBi. The antenna exhibits excellent radiation characteristics and a stable gain, making it highly suitable for UWB MIMO system applications.