Exposimetric Characterization of the Near-Field of a Portable Transceiver Emitting in the Ultrahigh Frequency Range and Simulation of the Electromagnetic Power Deposited in a Ferrimagnetic Biological Tissue Present in Such a Field

Abstract

A portable radiocommunication device usually face-held during its use was chosen for characterizing its electromagnetic near-field distribution in air. Set to emit on a frequency of 440 MHz for digital voice communication with a maximum input power of 5 W, its antenna parameters were analyzed and the maps of field strengths were depicted up to distances of 20 cm from the device by using of a dual-sensor exposimeter. Since the occupational exposure safety limit for incident field levels was exceeded closer than 12 cm from the transceiver (for the magnetic field component), it became interesting to quantify the power loss in an alleged case of a brain containing also magnetite particles. Up to the present, only the electric field component was of interest when investigating biological effects of such exposures. With the new evidence from 2016, that human brain contains four orders of magnitude more magnetite nanocrystals than it was known before, a question rises in connection to the magnetic response of tissues impinged by fields with significant magnitudes and covering the hundreds of MHz frequency range. Starting from this question, we set-up a simulation in which a tissue with ferromagnetic content was mimicked for initial dosimetric computations