Synthesize and high permittivity dielectric ceramics characterization of type BZT-BaTiZrO3 and BST - BaTiSrO3 for nonlinear transmission lines applications

Abstract

Nonlinear transmission lines LTNLs have been studied for the RF generation with applications in radars, mobile defense platforms and satellites. Their operation is based on the nonlinear behavior of the line electronic components as a function of applied voltage (capacitors) and or current (inductors). Nonlinear lines depending on the configuration and applied pulse in the input can be used for soliton generation or pulse compression. A promising research area is the high permittivity dielectric ceramics and high nonlinear behavior presented by these materials as function of applied voltage, which is essential for the NLTLs building. The frequency oscillation produced by line is a function of the voltage level at the input and nonlinearity rate of capacitor and/or inductor, starting from a few MHz and reaching up to a few tens of GHz. Other positive parameter using dielectric ceramics is the high dielectric strength which can reach several tens of kV/mm, allowing high power signals generation, resulting in greater rangers of the RF signal. In this project, the proposal is to synthesizing dielectric ceramics using the composition BaTiZrO3-BZT and BaTiSrO3-BST both dielectric ceramic with high electrical permittivity - µ >10000 related to high dielectric strength > 5kV/mm, depending of the doping elements concentration and the environmental conditions in which the material is synthesized. The characterization of this ceramic materials is performed as a function of applied voltage CxV, as a function of frequency Cxf and dielectric strength through dielectric breakdown tests. The dielectric ceramics produced in this project are intended to be used in high voltage capacitive nonlinear transmission lines - NLTLC or high voltage hybrid nonlinear transmission lines - NLTLH applied in the broadcast, military and space. (AU)