ABSTRACT
This paper presents a novel design for a compact, multiband, high-gain planar antenna operating in the millimeter wave spectrum. The antenna utilizes a unique approach to constructing its arms using ellipses, resulting in a miniaturized structure. This design achieves multiband functionality through multimode operation, where different modes are excited at different frequencies within the tapered slot and on the antenna arms. The antenna exhibits impedance matching over five distinct frequency namely: 16.3 GHz, 19.5 GHz, 29.5 GHz, 36.5 GHz, and 43.1 GHz with corresponding bandwidths of 0.8 GHz, 0.9 GHz, 1 GHz, 1.5 GHz, and 0.3 GHz respectively. To enhance gain, the antenna incorporates parasitic ring elements on each arm,with defected ground strategically positioned and dimensioned for optimal performance. Both simulation and experimental results demonstrate high gain across all bands, with average maximum gain values of approximately 3.12 dBi, 4.6 dBi, 4.2 dBi, 5.1 dBi, and 3.2 dBi for the respective bands. This compact design, with its multiband functionality and high gain, shows promise for various millimeter wave applications requiring efficient performance in a small form factor, including 5G communication, satellite communication, radar systems, and emerging technologies that utilize the millimeter wave spectrum.
