A novel millimeter-wave aperture-coupled magnetoelectric (ME) dipole antenna with a low-profile metallic geometry is proposed based on the 3-D printing technology. An impedance bandwidth of 53.7%, a gain up to 10.8 dBi, and stable unidirectional radiation patterns with the cross polarization of less than −38 dB are achieved by the antenna. Its operating mechanism and design process are studied in detail as well. In order to widen the bandwidth of the millimeter-wave full-corporate H-plane air-filled waveguide feed network, a wideband H-plane stepped waveguide T-junction with a compact size is then investigated, which has a bandwidth of about 50% for the reflection coefficient of less than −20 dB. By combining the presented radiating element with the feed network, an $8 \times 8$ ME dipole array is designed, printed, and tested in the Ka-band. An enhanced bandwidth of 31%, symmetric radiation patterns with the cross polarization of less than −35 dB, and a gain varying from 25.5 to 28.5 dBi are experimentally obtained. The proposed design demonstrates the advantage of utilizing the 3-D printing method to improve the operating characteristics of the millimeter-wave antenna array and is attractive for the emerging wideband millimeter-wave wireless applications.

中文翻译：

---

Ka 波段 3D 打印宽带阶梯波导馈电磁电偶极天线阵列

基于 3D 打印技术，提出了一种具有低剖面金属几何形状的新型毫米波孔径耦合磁电 (ME) 偶极天线。该天线实现了53.7%的阻抗带宽、高达10.8 dBi的增益和稳定的单向辐射图，交叉极化小于-38 dB。对其运行机理和设计过程也进行了详细的研究。为了拓宽毫米波全合体H面充气波导馈电网络的带宽，研究了一种尺寸紧凑的宽带H面阶梯波导T型结，其带宽约为50%反射系数小于−20 dB。通过将所呈现的辐射元件与馈电网络相结合，在 Ka 波段设计、印刷和测试了 $8 \times 8$ ME 偶极子阵列。通过实验获得了 31% 的增强带宽、交叉极化小于 -35 dB 的对称辐射模式以及从 25.5 到 28.5 dBi 变化的增益。所提出的设计展示了利用 3D 打印方法改善毫米波天线阵列工作特性的优势，并且对新兴的宽带毫米波无线应用具有吸引力。