Miniaturized Antenna Design for Wi-Fi 6E/Wi-Fi 7 Applications

Abstract

To mitigate performance degradation caused by variations in host-platform ground configurations, this paper presents a compact wideband printed antenna for Wi-Fi 6E and Wi-Fi 7 applications. Occupying an ultra-miniature footprint of only 18 × 15 mm2, the proposed antenna consists of an asymmetric T-shaped monopole (ATM), an open stub, and a meandered loop ground-line structure. The meandered ground line operates as a modified planar sleeve balun to reduce PCB-induced common-mode current propagation and improve robustness against representative host–ground variations. By controlling the electromagnetic coupling between the ATM radiator and the meandered ground loop, broadband impedance matching is achieved without additional matching circuits. The proposed antenna covers three operating bands: 2.4 to 2.5 GHz, 5.15 to 5.85 GHz, and 5.925 to 7.125 GHz. Measurement results demonstrate stable resonant frequencies and wide impedance bandwidths across the investigated host–ground configurations, with measured radiation efficiencies up to 88% at the investigated frequencies. The measured radiation patterns exhibit quasi-omnidirectional characteristics at 2.45 GHz, while multilobe behavior becomes more pronounced at 5.5 and 6.5 GHz due to higher-order modes associated with the meandered ground loop. A quantitative coverage-efficiency or minimum-realized-gain analysis is beyond the scope of this study. Although demonstrated using a USB wireless adapter, the proposed operating mechanism is associated with the antenna structure rather than the USB connector itself.