Modeling and Analysis of Spiral Antenna Properties for Research the Brain Radiation in the Microwave Range

This paper investigates a planar single-arm spiral antenna used to measure human brain radiation in the frequency range 3-5 GHz. The investigation was carried out using numerical modeling (finite elements method) by employing ANSYS Electromagnetics Suite 19.2. In this software, the model of brain tissues and antenna was built. An optimization of antenna parameters was carried out to obtain the best matching and sensing depth. Frequency dependence of antenna input impedance, reflection coefficient was computed, and also a volume distribution of electromagnetic field in the head tissue was obtained. An influence matching layer to antenna characteristics is investigate in case of deviation of electrical parameters of the head tissue top layers. The matching layer is located between the spiral antenna plane and the surface of the head. To validate the obtained results, an additional simulation was carried out by using another software EM simulator.