TY - JOUR AU - Назарько, А. І. AU - Водолазька, М. В. AU - Біденко, П. С. AU - Нелін, Є. А. PY - 2015/06/30 Y2 - 2024/03/29 TI - Input impedance characteristics of microstrip structures JF - Visnyk NTUU KPI Seriia - Radiotekhnika Radioaparatobuduvannia JA - RADAP VL - 0 IS - 61 SE - DO - 10.20535/RADAP.2015.61.72-81 UR - https://radap.kpi.ua/radiotechnique/article/view/1056 SP - 72-81 AB - <em>Introduction</em>. Electromagnetic crystals (EC) and EC-inhomogeneities are one of the main directions of microstrip devices development. In the article the input impedance characteristics of EC- and traditional microstrip inhomogeneities and filter based on EC-inhomogeneities are investigated. <em>Transmission coefficient characteristics.</em> Transmission coefficient characteristics of low impedance EC- and traditional inhomogeneities are considered. Characteristics are calculated in the software package Microwave Studio. It is shown that the efficiency of EC-inhomogeneity is much higher. <em>Input impedance characteristics of low impedance inhomogeneities</em>. Dependences of input impedance active and reactive parts of EC- and traditional inhomogeneities are given. Dependences of the active part illustrate significant low impedance transformation of nominal impedance. The conditions of impedance matching of structure and input medium are set. <em>Input impedance characteristics of high impedance inhomogeneities</em>. Input impedance characteristics of high impedance EC- and traditional inhomogeneities are considered. It was shown that the band of transformation by high impedance inhomogeneities is much narrower than one by low impedance inhomogeneities. Characteristics of the reflection coefficient of inhomogeneities are presented. Input impedance characteristics of narrowband filter. The structure of narrowband filter based on the scheme of Fabry-Perot resonator is presented. The structure of the filter is fulfilled by high impedance EC-inhomogeneities as a reflectors. Experimental and theoretical amplitude-frequency characteristics of the filter are presented. Input impedance characteristics of the filter are shown. <em>Conclusions</em>. Input impedance characteristics of the structure allow to analyse its wave properties, especially resonant. EC-inhomogeneity compared with traditional microstrip provide substantially more significant transformation of the the input impedance. ER -