Input impedance characteristics of microstrip structures

Authors

  • A. I. Nazarko National Technical University of Ukraine, Kyiv Politechnic Institute, Kiev, Ukraine
  • M. V. Vodolazka National Technical University of Ukraine, Kyiv Politechnic Institute, Kiev, Ukraine
  • P. S. Bidenko National Technical University of Ukraine, Kyiv Politechnic Institute, Kiev, Ukraine
  • E. A. Nelin National Technical University of Ukraine, Kyiv Politechnic Institute, Kiev, Ukraine

DOI:

https://doi.org/10.20535/RADAP.2015.61.72-81

Keywords:

input impedance, electromagnetocrystalline inhomogeneity, narrowband filter

Abstract

Introduction. 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. Transmission coefficient characteristics. 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. Input impedance characteristics of low impedance inhomogeneities. 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. Input impedance characteristics of high impedance inhomogeneities. 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. Conclusions. 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.

Author Biographies

A. I. Nazarko, National Technical University of Ukraine, Kyiv Politechnic Institute, Kiev

Nazarko A. I., PhD, Associate Professor

M. V. Vodolazka, National Technical University of Ukraine, Kyiv Politechnic Institute, Kiev

Vodolazka M. V., Postgraduate student

P. S. Bidenko, National Technical University of Ukraine, Kyiv Politechnic Institute, Kiev

Bidenko P. S., Postgraduate student

E. A. Nelin, National Technical University of Ukraine, Kyiv Politechnic Institute, Kiev

Nelin E. A., Doctor of Engineering, Professor

Published

2015-06-30

Issue

Section

Electrodynamics. Microwave devices. Antennas