A Compact Multifrequency Broadband Dual-Antenna System With Mutual Coupling Reduction for Wi-Fi 6E Application

In this letter, a compact multifrequency broadband dual-antenna system with mutual coupling reduction for Wi-Fi 6E application is proposed. The dual-antenna system consists of two identical inverted-F antennas (IFAs), and the minimum distance of two antennas is only 2 mm, yet the antenna system occupied a small size of 6.5 × 41 mm
²
(about 0.05
λ
_min
× 0.32
λ
_min
,
λ
_min
is the wavelength at the lowest frequency). A decoupling inductor is induced between two open ends of two antennas for lower band decoupling, while a modified decoupling branch and a modified neutralization line are introduced between two antennas for upper wide band decoupling. After adopting the three decoupling techniques, the dual-antenna system obtains remarkable isolation with |
S
₂₁
| > 22 dB in all desired bands of WLAN 2.4 GHz/5 GHz (2.4–2.484 GHz, 5.15–5.35 GHz, 5.725–5.825 GHz) and Wi-Fi 6E (5.925–7.125 GHz). These presented decoupling techniques are compact and low-cost and can be used for those designs of multifrequency broadband dual-antenna systems without adding extra size.