An endfire circularly polarized (CP) complementary antenna array is proposed for 5G applications. The proposed antenna is realized using a single-layered printed circuit board (PCB) with plated-through-hole technology and metal blocks. The antenna element consists of an open-ended substrate-integrated waveguide (SIW), an electric dipole, a double-sided parallel-strip line (DSPSL), and two metal blocks. It is simple in configuration and can achieve wide impedance and axial ratio (AR) bandwidths, stable gain and radiation patterns, and low back radiation. To increase the gain, a $1 \times 8$ antenna array is formed by integrating eight antenna elements with a planar 1–8 SIW feed network. The measurement results show that the proposed array can achieve an overlapping impedance and AR bandwidth of 23.8% from 56.3 to 71.5 GHz with an endfire left-handed CP (LHCP) gain from 14 to 15.3 dBic. The proposed array possesses all the salient features of the complementary source in symmetric and stable radiation patterns, low back radiation, and wide bandwidth.

中文翻译：

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用于 5G 应用的端射圆极化互补天线阵列

为 5G 应用提出了一种端射圆极化 (CP) 互补天线阵列。所提议的天线是使用具有镀通孔技术和金属块的单层印刷电路板 (PCB) 实现的。天线元件由开放式基板集成波导 (SIW)、电偶极子、双面平行带状线 (DSPSL) 和两个金属块组成。它配置简单，可以实现宽阻抗和轴比（AR）带宽、稳定的增益和辐射模式以及低背向辐射。为了增加增益，通过将 8 个天线元件与平面 1-8 SIW 馈电网络集成在一起，形成了一个 1 美元×8 美元的天线阵列。测量结果表明，所提出的阵列可以实现从 56.3 到 71 的重叠阻抗和 23.8% 的 AR 带宽。5 GHz，端射左手 CP (LHCP) 增益为 14 至 15.3 dBic。所提出的阵列在对称和稳定的辐射模式、低背辐射和宽带宽方面具有互补源的所有显着特征。