A Miniaturized and Wideband Millimeter-Wave 45° Differentially Fed Dual-Polarized Arrowhead-Shaped Patch Antenna Array

In this paper, a new miniaturized and wideband ±45° dual-polarized (DP) arrowhead-shaped patch antenna excited by the coaxial differentially fed (DF) structure is proposed for millimeter-wave (mmWave) wireless communications. The integration of the arrowhead-shaped patch and the coaxial DF structure enables both the feeding and radiating components to coexist on the same metallic layer, thereby facilitating a compact and low-profile antenna design with a simplified fabrication process while maintaining high polarization isolation. Moreover, the arrowhead-shaped radiation patches incorporating the shorting pins are innovatively designed for achieving a wide DP impedance bandwidth of 53.6% (23.9-41.4 GHz) without occupying additional area. To validate the reasonability of the proposed concept, a corresponding 1 × 4 antenna array is devised and measured. A wide measured impedance bandwidth of 58.5% (23-42 GHz) and a peak gain up to 10.7 dBi of the array are experimentally justified. Owing to the demonstrated performance characteristics, such as a miniaturized configuration, wide bandwidth, stable radiation performance, high level of system integration, simplified manufacture process and low cost, the proposed antennas are well-positioned as prospective candidates for the emerging mmWave applications in the era of 5G-beyond (B5G) and 6G.