TITLE:
Analysis and FDTD Modeling of the Influences of Microwave Electromagnetic Waves on Human Biological Systems
AUTHORS:
Anthony Bassesuka Sandoka Nzao
KEYWORDS:
Human Biological Systems, Microwaves, Coupling, SAR, Thermal Effects, Non-Thermal Effects, The FDTD Method, Maxwell’s Equations, Bio-Heat Equation, Electrical Model, Thermal Model
JOURNAL NAME:
Open Journal of Applied Sciences,
Vol.12 No.6,
June
21,
2022
ABSTRACT: The interactions of electromagnetic waves with the human body are complex
and depend on several factors related to the characteristics of the incident
wave, including its frequency, its intensity, the polarization of the tissue encountered, the geometry of the tissue and its
electromagnetic properties. That’s to say, the dielectric permittivity, the conductivity and
the type of coupling between the field and the exposed body. A biological
system irradiated by an electromagnetic wave is traversed by induced currents of non-negligible density; the water molecules present in the biological
tissues exposed to the electromagnetic field will begin to oscillate at the
frequency of the incident wave, thus creating internal friction responsible for
the heating of the irradiated tissues. This heating will be all the more
important as the tissues are rich in water. This article presents the
establishment from a mathematical and numerical analysis explaining the
phenomena of interaction and consequences between electromagnetic waves and
health. Since the total electric field in the biological system is unknown,
that is why it can be determined by the Finite Difference Time Domain FDTD
method to assess the electromagnetic power distribution in the biological
system under study. For this purpose, the detailed on the
mechanisms of interaction of microwave electromagnetic waves with the human
body have been presented. Mathematical analysis using Maxwell’s equations as
well as bio-heat equations is the basis of this study for a consistent result. Therefore, a thermal
model of biological tissues based on an electrical analogy has been developed.
By the principle of duality, an electrical model in the dielectric form of a
multilayered human tissue was used in order to obtain a corresponding thermal
model. This thermal model made it possible to evaluate the temperature profile
of biological tissues during exposure to electromagnetic waves. The simulation
results obtained from computer tools show that the temperature in the
biological tissue is a linear function of the duration of exposure to microwave
electromagnetic waves.