A modified 11-side polygon wide band-MIMO antenna with diversity characteristics for multiple FR1-band applications with SAR analysis for biomedical and IoT applications

Abstract This study proposes a modified 11-sided polygonal wideband MIMO antenna on a 1.6 mm FR4 substrate for next-generation wireless IoT applications. The antenna features a polygonal patch with a hook-shaped slot and a partial ground plane to achieve a wide impedance bandwidth of 3.725–7.525 GHz. Enhanced isolation is ensured through a partial ground structure with a decoupling element, maintaining S 12 < –20 dB across resonant frequencies. It demonstrates excellent diversity performance with ECC < 0.4, DG of 10 dB, TARC < 0 dB, and CCL < 0.1 bits s −1 Hz −1 , along with a peak gain of 5.6 dB and 97% efficiency. The design supports applications including 5G sub-6 GHz (N79), V2X communication, WLAN, Wi-Fi, and Wi-Fi 6E. Additionally, all Specific Absorption Rate (SAR) values are below the safe limit of 1.6 W kg −1 , confirming its suitability for practical deployment.