A Compact Dual-Band Antenna Using a Gap-Coupled Monopole Branch for Wi-Fi 6/6E/7 Applications

This paper proposes a compact multimode gap-coupled antenna for dual-band Wi-Fi 6/6E/7 applications. The proposed structure significantly improves bandwidth and efficiency while maintaining a low-profile, compact size, and planar design without the need for complex three-dimensional geometries or an external matching circuit. The antenna offers dual-band operations covering the 2.4–2.5 GHz and 5.15–7.125 GHz regions by using branch-induced multimode excitation and a U-shaped resonator. The simulated –10 dB impedance bandwidths of the proposed antenna are 440 MHz in the lower-frequency band (ranging from 2.24 GHz to 2.68 GHz)and 2220 MHz in the higher-frequency band (from 5.13 GHz to 7.35 GHz). In addition, the measured average total efficiencies are 70% in the lower band and 72% in the higher band, confirming stable radiation performance across the frequency ranges. Its two-dimensional radiation patterns also exhibit omnidirectional characteristics suitable for mobile antennas. The simple and planar structure of the proposed antenna makes it a strong candidate for compact wireless platforms.