A Compact Dual-Band Dual-Polarized Antenna Using Nonuniform Metasurface and Mushroom Structures for Wi-Fi 7 Applications

A dual-band dual-polarized antenna with compact size and high isolation is proposed for Wireless Fidelity (Wi-Fi) 7 applications. It employs a nonuniform metasurface and mushroom structures as the primary radiating elements for the dual-band operation. The metasurface is utilized for multiple resonances at the upper band, which are also loaded mushroom elements to generate the lower band. The radiators are coupled with two orthogonal microstrip lines through a crossed slot for the dual-polarized radiation. The slot is backed by a metallic cavity to reduce the back radiation. The final design with an overall size of $\text{0.48} \lambda _{L} \times \text{0.48} \lambda _{L} \times \text{0.075} \lambda _{L}$ ($\lambda _{L}$ is the free-space wavelength at 2.37 GHz) yields a 10 dB return loss bandwidth of 2.37 GHz to 2.50 GHz and 5.02 GHz to 7.15 GHz and an isolation of $\ge$ 23 dB. Its operational bandwidth completely covers 2.4 GHz/5 GHz/6 GHz Wi-Fi bands. Moreover, the dual-band dual-polarized radiation is validated by far-field measurements, which result in a cross-polarization level of $\leq -\text{20}$ dB and the peak gains of 5.2 dBi and 10.7 dBi at the lower and upper bands, respectively.