Abstract
This paper presents a four element dual-band multiple-input multiple-output (MIMO) antenna design operating at 28/38 GHz for millimeter wave wearable applications. The antenna incorporates a metasurface-inspired structure on its upper surface and utilizes a coplanar waveguide (CPW) feeding method. The design achieved a high level of isolation exceeding -20 dB between the inter-elements at both frequencies, with minimal impact from bending on the performance. A gain of 5.52 dBi with dual beam characteristics was attained. The MIMO antenna exhibited favorable envelope correlation coefficient (ECC) values below 0.01 and diversity gain (DG) exceeding 9.9 dB at both resonance frequencies. This approach of integrating metasurface with CPW fed in the design of flexible MIMO antennas demonstrates potential applications in wearable devices.