A novel approach of multiband real permittivity and permeability estimation of the magnetic composites using a modified under coupled multimodal (TE10p) substrate integrated waveguide (SIW) cavity is presented. The proposed schemes allow the accurate wideband microwave characterization of the magneto-dielectric composites by using the higher-order modes of the designed SIW cavity. The analytical closed-form modified formulation is developed to calculate the permittivity and permeability over the wide frequency range, 10–20 GHz. Consequently, a unified empirical formulation is also developed, which can be used to generate the approximate prior values of multimodal permittivity and permeability for the synthesized magnetic composites, which is usually not known in advance. The proposed analytical and empirical approaches are validated numerically and experimentally, corresponding to various test samples. The estimated parameters using the proposed analytical approach are found to be in quite close agreement, error <5%, with the corresponding reference values and empirically generated values.

中文翻译：

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新的基于衬底集成波导腔的统一多频带介电常数和磁导率估计方法

提出了一种使用改进的欠耦合多模态 (TE10p) 衬底集成波导 (SIW) 腔对磁性复合材料进行多波段实际介电常数和磁导率估计的新方法。所提出的方案允许通过使用设计的 SIW 腔的高阶模式对磁电介质复合材料进行准确的宽带微波表征。分析封闭形式的修正公式用于计算 10–20 GHz 宽频率范围内的介电常数和磁导率。因此，还开发了统一的经验公式，该公式可用于生成合成磁性复合材料的多模态介电常数和磁导率的近似先验值，这通常是事先未知的。所提出的分析和经验方法经过数值和实验验证，对应于各种测试样本。发现使用建议的分析方法估计的参数与相应的参考值和经验生成的值非常一致，误差 <5%。