微波能量传输以及无线通信系统中的天线设计, 追求剖面低、质量轻, 易与平面电路集成。基于此, 设计了一种具有谐波抑制功能的单馈背腔圆极化环缝天线。该天线工作在 5.8 GHz, 采用导波结构基片集成波导 (SIW)抑制表面波, 提高了天线增益。 SIW通过2排金属孔阵列集成在介质板上, 在介质板上蚀刻短路圆环缝隙, 辐射电磁波。采用 50 Ω微带线到 SIW过渡的背馈方式, 并在馈线上引入并联枝节, 有效抑制了高次谐波, 且实现了基于基片集成波导天线的谐波抑制。通过加工测试, 天线的轴比为 0.67 dB, 增益为6.9 dBi, 阻抗匹配良好, 前后比为 22 dB, 仿真结果与实测结果吻合良好。

In microwave energy transmission and wireless communications system, the antenna needs to be low-profiled, and easy to be integrated with planar circuits. A novel single fed cavity backed circularly polarized ring slot antenna with harmonic suppression function is proposed. The antenna operates at 5.8 GHz and adopts a novel guided wave structure, Substrate Integrated Waveguide(SIW), to suppress surface waves and increase antenna gain. The substrate integrated waveguide is integrated on the substrate through two rows of metal via, and the short circuit annular gap is etched on the substrate to radiate electromagnetic waves. Antenna fed by 50 Ω microstrip line to SIW transition is adopted, and a parallel branch in the feeding line is introduced to realize suppressing harmonics based on the substrate integrated waveguide structure. Through fabricating and testing, the axial ratio of the antenna is 0.67 dB, the gain is 6.9 dBi, the impedance matching is good, and the front to back ratio is 22 dB. The simulated results are in good agreement with the measured results.