Abstract
In this article, an eight-element ultra-wideband (UWB) Multiple-Input-Multiple Output (MIMO) antenna system is proposed for 3D non-planar applications. The proposed UWB-MIMO antenna is installed around a polystyrene block in the 3D-octagonal arrangement. The eight radiating elements are placed on the sides of the octagonal polystyrene block with top and bottom surfaces left open. The single antenna element consists of a modified Y-shaped radiating patch, epsilon-negative (ENG) metamaterial, and a partial ground plane. A modified pie-shaped decoupling structure is deployed at the back-side of the radiating patch to improve the isolation among array elements. Each antenna element is printed on a low-cost FR-4 substrate with dimensions of 28 mm <inline-formula> <tex-math notation="LaTeX">\times23 </tex-math></inline-formula> mm with coverage of the whole UWB spectrum from 3.1 to 10.6 GHz frequency band. The eight-port UWB-MIMO antenna system consists of symmetric and non-symmetric array configurations. Simulated and measured MIMO performance parameters i.e. Channel Capacity Loss (CCL) < 0.35, Envelope Correlation Coefficient (ECC) < 0.0025 and Total Active Reflection Coefficient (TARC) < −11 dB are in acceptable limits for both symmetric and non-symmetric configurations. The proposed MIMO antenna system is suitable for 3D system-in-package, indoor localization systems, and wireless personal area network applications in industries where multiple machines are connected to a central server wirelessly through such kinds of antennas in a rich scattering environment.