 This paper presents a compact vase-shaped two-port ultra-wideband, UWB, antenna which has been designed to overcome the challenges of broadband operation and isolation. The antenna consists of a circular monopole antenna embedded with multiple curved segments and a rectangular slotted ground plane. The antenna is optimized to operate over a wide range of frequencies from 4 to 12.1 GHz. The antenna's performance is improved through the use of a decoupled inverted pendulum-shaped parasitic element on the ground plane. The resulting UWB MIMO antenna exhibits excellent isolation, low cross-coupling, high efficiency, and good time-domain characteristics. This article was authored by Sabash Bodagura Kampanna, Rajsekar, Sibi Radhar, Praveen Kumar, and others.