Design and optimisation of defected ground structure slotted MIMO antenna for maritime mobile, broadcasting and fixed mobile communications

Abstract The proposed article presents a novel dual-port MIMO antenna design incorporating a defected ground structure (DGS) and passive slots to achieve enhanced performance in terms of high isolation, high gain and multiband response. Unlike conventional approaches, the proposed antenna undergoes a three-stage design evolution, introducing triangular and D-shaped slots in the patch, as well as vertical and horizontal slits in the ground, and optimising inter-element spacing to minimise mutual coupling. The optimum design exhibits triple-band operation, featuring a minimum reflection coefficient of − 38.86 dB, a maximum gain of 6.88 dB, peak bandwidth of 4.048 GHz, peak directivity of 4.45 dB, and peak radiation efficiency of 70%. The antenna achieves high isolation of 60 dB and satisfactory diversity performance, including ECC, TARC, and DG values within acceptable limits. The low-cost FR4 substrate, validated through measurements, offers a compact, cost-effective, and high-performance solution. Compared to existing MIMO designs, the proposed work provides a significant improvement in isolation, gain, and bandwidth while maintaining a low-profile structure, making it particularly suitable for modern wireless communication environments. The proposed method is ideal for Maritime Mobile, Broadcasting, and Fixed Mobile communication.