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Information × Registration Number 0308U001544, 0107U000692 , R & D reports Title Development and design of new facillities of forming of the directed radiation of sverhkorotkih impulsive signals popup.stage_title Створення моделі поширення імпульсного сигналу у конусній лінії передачі Head Kolchigin N., Katrich V, Registration Date 08-02-2008 Organization Kharkov National University named after V.N.Karazin popup.description2 Report on R&D Project 20 p., 1 fig., 8 references. Object of the research is process of propagation of arbitrary transient signals in the spherical coordinate system in presence of angular dependence in constitutive parameters of the medium and with optional conical perfect electric conductors (inhomogeneous conical lines). Aim of the work is to develop an electrodynamics model of propagation of an impulse signal in an inhomogeneous conical lines; this model will further be used for simulating ultrawideband radiators, their optimization, design of new ones, and improvement of the known antennas for pulse radiation. Among such antennas there should be mentioned TEM-horns, bow-tie antennas, tapered slot antennas (aka Vivaldi antenna). This research is a continuation of the research and development studies conducted at the chair of theoretical radiophysics of Kharkov National University during 2004-2006. The subject of the study is the process of transient electromagnetic waves propagation in an inhomogeneous cone transmission lines. The method of studying is obtained as a modification of the Mode Basis Method in the spherical coordinate system, at this it was accounted for existence of TEM-wave and inhomogeneity and transience of the constitutive parameters. Especially effective consideration of the medium inhomogeneity is in the case when coordinate dependence of the permittivity and permeability can be presented in the factorized form as a product of a function of transverse (angular) coordinates and a function of temporal variable and longitudinal (radial) coordinate. In the study the formulae are derived for expansion of the full electromagnetic field on the mode basis; it is proved that the eigenfunctions of the stated vector boundary problems constitute indeed a basis (mode basis) in the whole solution space for Maxwell equations; a scalarizing substitution is obtained that allows reduce the vector eigenvalue problems to the scalar ones, at this the vector functions are easily expressed as derivativesof the scalar potentials; the system of evolutionary equations is derived that governs the evolutionary coefficients, which are the field expansion coefficients; the obtained system of evolutionary equations consists of inhomogeneous linear partial differential equations with variable coefficients of the first and second order. MODE BASIS METHOD IN SPHERICAL COORDINATE SYSTEM, INHOMOGENEOUS CONICAL TRANSMISSION LINE, INHOMOGENEOUS MEDIUM, IMPULSE SIGNALS. Conditions of the report acquisition: under the treaty, 61077, Kharkiv, Svobody sq. 4. Product Description popup.authors popup.nrat_date 2020-04-02 Close