Design of compact wideband circularly polarized (CP) antennas is challenging due to the necessity of simultaneous handling of several characteristics [reflection, axial ratio (AR), and gain] while maintaining a small size of the structure. Antenna redesign for various operating bands is clearly more difficult yet practically important because intentional reduction of the bandwidth (e.g., by moving the lower edge of the operating band up in frequency) may lead to a considerable size reduction, which can be beneficial for specific application areas. This article proposes a rigorous approach to rapid redesign of miniaturized CP antennas involving inverse surrogate models and fast electromagnetic (EM)-based parameter tuning. Our methodology allows for a precise control of the lower operating frequency of the CP antenna (both in terms of the impedance and AR bandwidth) and accomplishing the geometry parameter scaling at an extremely low cost of a few EM analyses of the structure at hand. Our methodology is demonstrated by redesigning a compact wide slot CP antenna in the range of 3.2–5.8 GHz. The proposed approach can be used for fast rendering of the bandwidth/size tradeoffs (the footprints obtained for the verification structure range from 783 to 482 mm2), thus determining the most suitable designs for particular applications. The numerical findings are experimentally validated.

中文翻译：

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使用逆代理和基于 EM 的快速参数调谐的紧凑型宽带圆极化天线的快速重新设计和带宽/尺寸权衡

由于需要同时处理多个特性 [反射、轴比 (AR) 和增益]，同时保持结构的小尺寸，紧凑型宽带圆极化 (CP) 天线的设计具有挑战性。为各种工作频段重新设计天线显然更加困难，但实际上很重要，因为有意减少带宽（例如，通过将工作频段的下边缘向上移动）可能会导致尺寸显着减小，这对特定应用是有益的领域。本文提出了一种严格的方法来快速重新设计小型化 CP 天线，包括逆代理模型和基于快速电磁 (EM) 的参数调整。我们的方法允许精确控制 CP 天线的较低工作频率（在阻抗和 AR 带宽方面），并以极低的成本对手头的结构进行一些 EM 分析来完成几何参数缩放。我们的方法是通过重新设计 3.2-5.8 GHz 范围内的紧凑型宽缝 CP 天线来证明的。所提出的方法可用于快速渲染带宽/尺寸权衡（验证结构获得的足迹范围为 783 至 482 mm2），从而确定最适合特定应用的设计。数值结果经过实验验证。我们的方法是通过重新设计 3.2-5.8 GHz 范围内的紧凑型宽缝 CP 天线来证明的。所提出的方法可用于快速渲染带宽/尺寸权衡（验证结构获得的足迹范围为 783 至 482 mm2），从而确定最适合特定应用的设计。数值结果经过实验验证。我们的方法是通过重新设计 3.2-5.8 GHz 范围内的紧凑型宽缝 CP 天线来证明的。所提出的方法可用于快速渲染带宽/尺寸权衡（验证结构获得的足迹范围为 783 至 482 mm2），从而确定最适合特定应用的设计。数值结果经过实验验证。