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Information × Registration Number 0213U001780, 0110U001426 , R & D reports Title Investigation of transient and resonance radiation of electrically small TEM antennas popup.stage_title Head Kolchigin Nikolay, Butrym A lexandr, Registration Date 12-02-2013 Organization Kharkov National University named after V.N. Karazin popup.description2 The object of the research is the process of radiation of arbitrary non-stationary signals by antennas based on non-uniform conical TEM-line. The aim of the work consists in investigation of the laws of mode transformations in a non-uniform conical line into the radiation field, deter-mination of the optimal profile for a non-uniform biconical antenna that yields minimum lower cutoff frequency, as well as to investigate the possibility of resonance radiation of such small antennas in due to resonance on trapped modes. This research is a continuation of the research and development studies conducted at the chair of theoretical radiophysics of Kharkov National University during 2006-2010. The subject of the study is the electromagnetic radiation field. The method of investigation is based on several new computation methods that were ad-vanced based on the mode basis method and the finite difference in time domain method. In particu-lar an open waveguide was considered. For solution of the problems several algorithms for calculat-ing fields in a non-uniform conical waveguide based on expansion of fields into coupled modes were developed. Also an algorithm for calculating the mode field distribution in a conical waveguide with a complex cross-sectional shape is created. In particular, based on the method of mode expansions in the time domain a theoretical model and a computer program for finding field distributions in conical lines with complex cross-sectional shape and with dielectric filling is proposed. The mathematical model of the pulse radiation of an antenna based on a non-uniform conical TEM-line is created. Using the profile with variable imped-ance several new antenna constructions are proposed. Optimization of the antenna in order to decrease the lower frequency radiation limit led to the non-uniform biconical antenna and its planar analog. A theoretical model and numerical analysis of the resonance radiation of small antennas, which is based on a non-uniform bicone antenna with di-electric filling are proposed. Physical features of the formation of the radiation field in a non-uniform conical line with resonances at trapped modes are revealed. MODE BASIS METHOD, CONICAL LINE, FINITE DIFFERENCE IN TIME DOMAIN METHOD, PULSE ANTENNA, TRAPPED MODES Product Description popup.authors Казанський О. Кочетов Б. Легенький М. Шаркова М. popup.nrat_date 2020-04-02 Close