Bandwidth Enhanced Saucer-Shaped Dual-Polarized Millimeter-Wave Antenna for Terminal Application

In this paper, we proposed a compact wideband dual-polarized (DP) millimeter-wave (mmWave) antenna for the fifth/sixth generation ($5 \mathrm{G} / 6 \mathrm{G}$) mobile terminal application. Two orthogonal L-shaped probes with different heights are implemented to excite the saucer-shaped patch antenna. Besides, four quasi-monopole parasitic structures are introduced inside the patches for achieving a wider DP impedance bandwidth of $55 \%$ (24.3-42.7 GHz), while keeping a compact size of $3.3 \mathrm{~mm} * 3.3 \mathrm{~mm} * 1.1 \mathrm{~mm}$. Additionally, the antenna presents high polarization isolation less than $\mathbf{- 2 0} \mathbf{d B}$ and flat gain response with a peak gain of $7.3 \mathbf{d B i}$. It also exhibits stable radiation patterns, characterized by low cross-polarization levels below -25 dB. Moreover, the antenna is designed to be compatible with a standard commercial printed circuit board (PCB) fabrication facility, which contributes to the merits of low fabrication complexity and cost-effectiveness. Overall, the proposed antenna could be a competitive candidate for burgeoning $5 \mathrm{G} / 6 \mathrm{G} \mathbf{~ m m W a v e}$ applications.