Dual band substrate defected compact quad port MIMO antenna for 5 G MM-wave wireless communications with performance enhancement

This paper presents design and performance evaluation of a novel four-port MIMO antenna developed on a Rogers RT-5880 substrate having size of 30 × 30 × 1.6 mm³. A unique defected structure (DS) incorporating substrate defectiveness is introduced that provides -10 dB impedance bandwidth from 26.1 GHz to 32 GHz, and 35.9 GHz to 41 GHz. The DS integration leads to 1.6 GHz bandwidth enhancement at 38 GHz, alongside 3–4 dB gain enhancement. The antenna exhibits high gains of 7.5 dBi and 9.3 dBi at 28 GHz and 38 GHz, respectively. Moreover, DS enhances isolation in MIMO elements from 17 dB to 24 dB at 28 GHz and 16 dB to 23.5 dB at 38 GHz. It provides envelope correlation coefficient below 0.003 with diversity gain 10 dB. The result indicates that proposed MIMO antenna can the utilized for high-data-rate, low-latency communications, especially for 5G-enabled IoT and vehicular network applications.