A Low-Profile and Wideband Dual-Polarized Back-Cavity Flush-Mountable Antenna Tailoring through Magnetodielectric Materials

This communication presents a novel dual-polarized back-cavity flush-mountable antenna, with low-profile and wideband characteristics enabled by magnetodielectric materials. The proposed antenna consists of two pairs of orthogonal dipoles, two Y-shaped feeds, a ground plate, a metal cavity, two metal sleeves, and magnetodielectric materials. Compared to non-magnetodielectric materials, the variation in both the real and imaginary parts of the permeability in magnetodielectric materials effectively reduces theQ-factor of the antenna, resulting in low-profile and wideband characteristics. Orthogonal dipoles are used to obtain ±45° dual-polarized radiation. The mentioned structures are wholly embedded into a metal cavity for potential flush-mountable applications. To verify the design, a prototype is fabricated and tested. The prototype dimensions are 0.57λL× 0.57λL× 0.09λL, where λLis the free-space wavelength at the lowest operating frequency. The simulated and measured results are in good agreement, with an impedance bandwidth of 47.8% (1.67-2.72 GHz), port-to-port isolation greater than 32 dB, the peak realized gains of 8.68 dBi and 8.72 dBi for Ports 1 and 2, respectively, and a 3 dB beamwidth of 67° ± 8° for each polarization over the operating band.