Радиофизика и электроника (Dec 2016)
ON THE “TREE” VERTICAL ELECTRIC ELF ANTENNA
Abstract
Development of new antennas for reception of radio signals was and remains an actual problem. We model and estimate the efficiency of unusual design of the vertical electric antenna detecting ELF (3…3 000 Hz) radio signals. The antenna must be sensitive to the vertical electric field of radio waves traveling in the spherical Earth–ionosphere cavity at frequencies of global electromagnetic (Schumann) resonance ranging from 4 to 40 Hz. It is formed by a couple of electrodes fixed at the tree trunk at different heights separated by several meters. Such a design is unusual, and its workability might seem dubious. We show with the help of model computations that the tree antenna is a rather effective ELF sensor, especially in fair weather condition. We also discuss the requirements for the tree antenna pre-amplifier.
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