A Millimeter-Wave Wideband Dual-Polarized Integrated DRA Array With Improved Isolation

This letter presents a millimeter-wave (mmWave)-integrated dielectric resonator antenna (DRA) array. Within the context of a 2-D array possessing broadband and dual-polarization features, mutual coupling between elements is suppressed. The DRA elements operate in a pair of high-order modes (TE
₁₀₃
and TE
₀₁₃
), and each antenna is excited by a pair of orthogonal Y-shaped feeding lines through a cross coupling slot. The proposed dielectric resonator (DR) consists of three portions with different permittivity, facilitating a permittivity transition from low to high and then back to low. This design improvement enhances impedance matching between the feed and the DR, as well as between the radiator and the air, resulting in improved reflection coefficients and increased isolation. In addition, all the dielectric materials with the same permittivity are integrated and manufactured as a single piece to mitigate manufacturing and assembly errors, thereby minimizing potential performance degradation. An array prototype consisting of 4 × 4 antenna elements is fabricated for demonstration. The array achieves a common −10 dB impedance bandwidth of 30.6% with an overlapped scanning coverage ranging from −47° to 47° at 27 GHz. The proposed design has the advantages of wide bandwidth, improved isolation, and wide scanning angle, which are attractive for 5G mmWave application.