A circularly polarized (CP) broad-beam parallel-plate (PP) antenna is investigated. The difference between the phase velocities of two PP orthogonal modes is used to obtain CP fields. The two orthogonal modes are excited by an inclined slot fabricated on the ground plane that connects the two PPs. By tuning the slot length, the impedance can be easily matched. To reduce the cross-polarized fields, a modified CP PP antenna with semicircular plates is introduced. ANSYS HFSS was used to simulate the antennas and prototypes were fabricated to verify the simulations. Both the original and modified CP PP antennas have an overlapping antenna bandwidth of ~13.0% and an antenna gain of ~8 dBic. As compared with other broad-beam antennas, the two PP antennas have simpler and larger structures, easing their fabrications especially at millimeter-wave frequencies. A design guideline is developed.

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关于圆极化平行板天线

研究了圆极化 (CP) 宽波束平行板 (PP) 天线。两个 PP 正交模式的相速度之间的差异用于获得 CP 场。两个正交模式由连接两个 PP 的接地平面上制造的倾斜槽激发。通过调整插槽长度，可以轻松匹配阻抗。为了减少交叉极化场，引入了一种带有半圆板的改进型 CP PP 天线。ANSYS HFSS 用于模拟天线，并制造原型以验证模拟。原始和修改后的 CP PP 天线都有~13.0% 的重叠天线带宽和~8 dBic 的天线增益。与其他宽波束天线相比，两个PP天线结构更简单，体积更大，简化他们的制造，尤其是在毫米波频率下。制定了设计指南。