In the present work, the band-pass filter characteristics of a coaxial waveguide with an impedance coated groove on the inner wall and perfectly conducting outer wall is analyzed rigorously through the Wiener–Hopf technique. By using the direct Fourier transform, the related boundary value problem is reduced to the Wiener–Hopf equation whose solution contains infinitely many constants satisfying an infinite system of linear algebraic equations. These equations are solved numerically and the field terms, which depends on the solution obtained numerically, are derived explicitly. The problem is also analyzed by applying a mode-matching technique and the results are compared numerically. Besides, some computational results illustrating the effects of parameters such as depth of the groove, surface impedances and radii of the walls are also presented.

中文翻译：

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内壁带有阻抗涂层凹槽的同轴波导的 Wiener-Hopf 方法

在目前的工作中，通过 Wiener-Hopf 技术严格分析了同轴波导的带通滤波器特性，该同轴波导内壁带有阻抗涂层凹槽，外壁完美导电。通过使用直接傅里叶变换，相关的边值问题被简化为 Wiener-Hopf 方程，其解包含满足无限线性代数方程组的无限多个常数。这些方程以数值方式求解，并明确导出依赖于数值求解的场项。该问题还通过应用模式匹配技术进行了分析，并对结果进行了数值比较。此外，还提供了一些计算结果，说明了凹槽深度、表面阻抗和壁半径等参数的影响。