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Information × Registration Number 0213U001782, 0110U001425 , R & D reports Title Excitation of electromagnetic waves by irregular vibrator and slotted-guide structures in electrodynamic volumes with coordinate borders popup.stage_title Head Katrich Victor, Nesterenko Mikhail, Registration Date 12-02-2013 Organization Kharkov National University named after V.N. Karazin popup.description2 Object of research - processes of excitation, radiation and scattering of electromagnetic fields by the irregular dipole and slot-hole structures located in free space and waveguide structures. The project purpose is creation of mathematical models irregular, including with an impedance surface, dipole and slot-hole structures, as much as possible effective for carrying out of multiple parameter calculations of electrodynamic characteristics of structures with any geometrical and material parameters, definition of physical properties of the fields radiated by such structures in all zones of radiation. Are developed and modified mathematical the valid analytical and numerically-analytical methods of the solution of boundary problems of electrodynamics connected with excitation and radiation of electromagnetic fields by thin impedance vibrators with arbitrary point of excitation, with variable along them a surface impedance, the radial impedance vibrator on ideally conducting sphere with any arbitrary of excitation, system of dipole radiators of the different sizes and with various values of surface impedances in free space. Results of optimisation of input parameters of vibrators by change of a surface impedance for increase in efficiency of their excitation are presented; effect of position of a point of excitation and value of a surface impedance on the radiation pattern and distribution of an electromagnetic field in a near zone of radiation is analysed. Radiators Jagi-Uda on the basis of impedance vibrators are simulated. The averaging method solves a problem of scattering of electromagnetic waves by a resonant iris with any way orientated slot in a rectangular waveguide. Mathematical models of radiating systems on the basis of inclined slots in a wall of a rectangular waveguide, cross-section ring and arc slots in the screen of a semi-infinite coaxial line are developed and the multiple parameters analysis of physical properties of the electromagnetic fields raised by such structures is excited. For optimisation of characteristics of an directivity of radiating systems the modified point objective function which considers mutual coupling of radiators of antenna arrays is offered and provides exact performance of conditions of optimisation in the prescribed directions. The iterative algorithm with use of point objective function in procedure of optimisation of side lobe levels of radiation pattern of linear regular and irregular dipole and waveguide-slot antenna arrays is developed. Results SRW make it possible to create of waveguide-slot and dipole radiators with complex electrodynamic structure, multi-element arrays and small-sized radiating systems and feeder devices with the improved and new functionality. ELECTROMAGNETIC WAVES, DIFFRACTION, WAVEGUIDE-SLOT RADIATOR, DIPOLE RADIATOR, IMPEDANCE RADIATOR. Product Description popup.authors Берднік С. Дахов В. Кийко В. Лященко В. Медвєдєв М. Нестеренко М. Пшенична С. popup.nrat_date 2020-04-02 Close