Reducing Q Factor in a Near Half-Mode Miniaturized Patch Antenna Using Slotted Ground

The significance of compact, miniaturized antennas in modern wireless communication lies in their efficient use of space, adaptability, and versatility. Coupled microstrips are known for miniaturising the electrical dimensions of a patch antenna by introducing capacitive loading. This in turn increases the propagation constant and enhances slow-wave characteristics, thereby reducing the electrical dimensions of the antenna. In this work, a dual coupled slot based miniaturised antenna operating at near half-mode resonance is proposed. The electrical dimensions of the structure were reduced to $0.15\times 0.15 \lambda_{0}^{2}$, but with a very low bandwidth (1.8%). To improve the bandwidth of the antenna without significantly sacrificing it electrical dimensions, slots were etched out from the ground plane of the antenna. This adds some reactance in the surface current path, which reduces the Q-factor and increases bandwidth. The increase in electrical dimensions of the antenna is found to be within tolerable limits. The proposed work is compared with prior existing literature and is found to have a larger figure of merit in terms of electrical dimensions, bandwidth and gain.