标题： 波导馈电的谐振超材料元件的等效电路模型 显示英文标题

标题： Equivalent Circuit Models for Waveguide-Fed, Resonant, Metamaterial Elements

摘要： 我们提出了一种方法，用于提取波导馈电的谐振超材料元件的等效电路模型，例如互补电感-电容元件（cELC）。 从单个波导馈电的cELC的散射参数中，可以确定有效的电极化率和磁极化率，这些参数可以用等效集总元件电路组件来表示。 该电路模型为理解cELC的电磁散射特性提供了深刻的见解，并有助于优化元件的设计。 我们发现，平面的、固有谐振的、波导馈电的元件具有一组共同的性质，这些性质对其耦合、最大辐射以及其他关键散射参数施加了限制。 此外，与简单的缝隙和其他非谐振孔径不同，谐振元件在等效电路中引入了一个有效的变压器，以解释此类元件在谐振时出现的场增强现象。 我们引入了一种通用且稳健的方法，通过拟合提取的极化率来确定有效电路参数，并将这种方法扩展到与物理集总电路元件（如封装电容器或变容二极管）集成的谐振超材料元件。 我们发现解析预测与全波仿真之间具有极好的一致性，这意味着只需一次或两次全波仿真即可确定cELC在添加任意外部集总元件时的特性。 这种方法可以极大地提高超表面天线孔径设计的效率，特别是在需要元件响应库的情况下。 显示英文摘要

摘要： We propose an approach to extracting equivalent circuit models for waveguide-fed, resonant metamaterial elements, such as the complementary, electric inductive-capacitive element (cELC). From the scattering parameters of a single waveguide-fed cELC, effective electric and magnetic polarizabilities can be determined that can be expressed in terms of equivalent lumped element circuit components. The circuit model provides considerable insight into the electromagnetic scattering properties of cELCs as a function of their geometric parameters and imparts intuition useful for element optimization. We find that planar, inherently resonant, waveguide-fed elements exhibit a set of common properties that place constraints on their coupling, maximum radiation, and other key scattering parameters. In addition, unlike simple slots and other non-resonant irises, resonant elements introduce an effective transformer to the equivalent circuit that accounts for the field enhancement occurring in such elements at resonance. We introduce a general and robust method to determine the effective circuit parameters by fitting to the extracted polarizability, extending the approach to resonant metamaterial elements integrated with physical lumped circuit components, such as packaged capacitors or varactors. We find excellent agreement between the analytical predictions and full-wave simulations, such that with one or two full-wave simulations the properties of the cELC can be determined for any externally added lumped elements. This approach can be leveraged to dramatically increase the efficiency of metasurface aperture design, especially when libraries of element responses are required.