Artificial Magnetic Conductor backed Printed Monopole MIMO Antenna for Millimeter-Wave 5G WBAN Applications

A low profile, high gain, and with improved safety features artificial magnetic conductor (AMC) backed printed monopole multiple-input-multiple-output (MIMO) antenna for millimeter-wave (mm-wave) 5G wireless body area network (WBAN) applications is presented. The proposed design consists of a printed monopole in the top layer with a partial ground plane. A single antenna element along with the connector model has initially been designed with a detailed analysis and subsequently, a two-port MIMO antenna backed by an AMC structure is realized. The AMC structure consists of $5\times 4$ unit cells that are made up of two interconnected I-shaped slots etched out of a metallic patch (Jerusalem Cross). With the use of AMC, the antenna gain at 28 GHz increases by 4.89 dBi due to the suppression of surface wave. The specific absorption rate (SAR) and power density are also reduced by the AMC. The performance of the AMC-backed antenna remains consistent in the two-port MIMO antenna having an overall dimension of $25\times 40\times 3.7\ \text{mm}^{2}$. In addition, several MIMO parameters are calculated, and their results are found to be suitable for 5G WBAN applications. Finally, the antenna prototype as well as the AMC are fabricated and their measured results conform to the simulated responses, validating the proposed concepts.