Department of Electronic and Electrical Engineering, University College London, Torrington Place, London WC1E 7JE, UK.
Sensors (Basel). 2023 Jan 17;23(3):1067. doi: 10.3390/s23031067.
In this paper, we proposed a new wideband circularly polarized cross-fed magneto-electric dipole antenna. Different from conventional cross-dipole or magneto-electric dipole antennas, the proposed simple geometry realizes a pair of complementary magnetic dipole modes by utilizing the two open slots formed between the four cross-fed microstrip patches for achieving circular polarization and high stable gain across a wide frequency band. No parasitic elements are required for extending the bandwidths; therefore, both the radiation patterns and in-band gain are stable. The simulated field distributions demonstrated the phase complementarity of the two pairs of magnetic and electric dipole modes. A parametric study was also performed to demonstrate the radiation mechanism between the electric and magnetic dipole modes. The radiating elements are realized on a piece of double-sided dielectric substrate fed and mechanically supported by a low-cost commercial semirigid cable. The overall thickness of the antenna is about 0.22λ at the center frequency of axial ratio bandwidth. The measured results show a wide impedance bandwidth (|| < -10 dB) of 70.2% from 2.45 to 5.10 GHz. The in-band 3-dB axial ratio bandwidth is 51.5% from 3.0 to 5.08 GHz. More importantly, the gain of the antenna is 9.25 ± 0.56 dBic across the 3-dB axial ratio bandwidth.
在本文中，我们提出了一种新的宽带圆极化交叉馈电磁电偶极子天线。与传统的交叉偶极子或磁电偶极子天线不同，所提出的简单几何形状通过利用四个交叉馈电微带贴片之间形成的两个开口槽来实现一对互补的磁偶极子模式，从而实现圆极化和在宽频带内具有高稳定增益。不需要寄生元件来扩展带宽；因此，辐射方向图和带内增益都很稳定。模拟的场分布证明了两对磁偶极子和电偶极子模式的相位互补性。还进行了参数研究以演示电偶极子和磁偶极子模式之间的辐射机制。辐射元件位于双面介电基板上，由低成本的商业半刚性电缆馈电和机械支撑。天线的总厚度在中心频率的轴比带宽处约为 0.22λ。测量结果显示，在 2.45 至 5.10 GHz 范围内具有 70.2%的宽阻抗带宽（||< -10 dB）。在带内，3 dB 轴比带宽为 51.5%，频率范围为 3.0 至 5.08 GHz。更重要的是，天线在 3 dB 轴比带宽内的增益为 9.25 ± 0.56 dBic。
