Ohurtsova T. Metal loops with a ferrite rod as receiving antennas of ultra-wideband pulsed electromagnetic fields

The object of the study is electromagnetic processes that occur during the diffraction of ultra-wideband (UWB) pulsed electromagnetic fields at magnetodielectric rods and rods with electrically conductive loops on them. Objective is to identify and study the physical regularities of the interaction of the pulsed electromagnetic field of nano- and subnanosecond duration with ferrite rods and use these regularities to design small receiving antennas for sensitive undistorted reception of electromagnetic pulses. The Fourier method, Fourier integral transformation method, finite time domain difference (FDTD) method, method of direct measurements of electrical parameters of signals are used in the work. Theoretical and practical results, scientific novelty: according to the results of numerical modeling of the problems of diffraction of pulsed electromagnetic fields on a ferrite rod, the amplitude-time dependences of the pulses at the output of the receiving ferrite antenna are investigated; the conditions of sensitive undistorted reception of electromagnetic field pulses by multi-element ferrite antennas are investigated; the criteria of sensitive undistorted reception of signals by the ferrite antenna of the UWB signals in the form of the most common functions are determined; a method for measuring the frequency dependence of the magnetic permeability of ferrite rods is proposed; a method of increasing the sensitivity of undistorted reception of UWB pulses by summing the signals received by several loops is extended for ferrite antennas; the use of several loops at a ferrite antenna reduces the rise time of the transient characteristics of the antenna. Degree of implementation: the studied regularities can be used to create UWB ferrite pulsed receiving antennas. Scope of application is for the design of UWB radars of various applications, for researchers and developers of radar equipment of such class.