Fluctuations in the signal of optical coefficients of propagative electromagnetic (EM) waves in plasma, can cause problems in phase analysis, especially in microwave diagnostic systems which are based on the reflection, and transmission of EM waves in the vicinity of cut-off layer of the plasma. In this study, optical properties of EM wave propagation in a single layer, homogeneous, and partially ionized plasma slab are investigated. For realistic analysis of propagation characteristics of the EM wave in the plasma slab, multiple reflections of the EM wave from plasma-vacuum boundaries, known as incoherent internal reflections (IIR) are considered. Optical coefficients of the EM wave are numerically simulated in terms of the plasma parameters and wave frequency, with and without consideration of the incoherent internal reflections effect. It was found that in the low-loss collision regime, the cut-off fluctuations of the optical coefficients can be filtered considering the incoherent internal reflections of the EM wave. Such analysis of the EM wave propagation in plasma slab can be considered the primary physical design of diagnostic facilities and EM wave absorbing structures operating in the cut-off frequency ranges.

中文翻译：

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研究电磁波在均匀碰撞等离子板中传播的近截止特性

等离子体中传播电磁 (EM) 波的光学系数信号的波动会导致相位分析出现问题，特别是在基于电磁波在截止层附近的反射和透射的微波诊断系统中等离子体。在这项研究中，研究了 EM 波在单层、均匀和部分电离的等离子体板中传播的光学特性。为了真实地分析 EM 波在等离子板中的传播特性，我们考虑了 EM 波从等离子-真空边界的多次反射，即非相干内反射 (IIR)。EM波的光学系数根据等离子体参数和波频率进行数值模拟，考虑或不考虑非相干内反射效应。发现在低损耗碰撞状态下，考虑到 EM 波的非相干内反射，可以滤除光学系数的截止波动。这种对等离子板中电磁波传播的分析可以被认为是诊断设施和在截止频率范围内运行的电磁波吸收结构的主要物理设计。