A Compact 2-Port Ultra-Wideband MIMO Antenna With Modified Ground Plane

This article presents a microstrip fed 2-port antenna with Ultra-wideband (UWB) and multiple-input multiple-output(MIMO) behavior. The MIMO antenna has orthogonally placed flower-shaped radiators. The novelty of design lies in its design as all the unit cell elements of proposed MIMO antenna are orthogonal to each other hence no additional decoupling structure is utilized to improve isolation making antenna design simple and easy to fabricate. To provide UWB characteristics easily in the proposed design, the ground plane is modified by slotting it with a compliment of half radiator shape geometry. In addition, a rectangular slot is cut from the upper edge of the ground plane beneath the feedline to improve impedance bandwidth. The design is proposed using 50×25 mm
²
FR4 Substrate having a dielectric constant of 4.4. The simulated results of the presented design provide a bandwidth of 3 to 12 GHz with reflection coefficients S
₁₁
, S
₂₂
very less than -10dB and the mutual coupling coefficients for respective antenna elements are observed to be less than 15 dB. The design also provides an omnidirectional radiation pattern with dual-frequency bands characteristics and wideband behavior. Moreover, the diversity performance of the antenna is performed in terms of ECC, diversity gain, and TARC. Simulated results are presented using Ansys HFSS and are in good agreement.