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Mobile Communication Fields in Biological Systems
of the population, and statistical recording of illnesses and symptoms, research on the
biological effects of RF EM radiation emitted by mobile communication devices can
also be carried out numerically and experimentally. Selecting the appropriate methods
for numerical and experimental dosimetry and performing uncertainty assessment to
validate the derived results are of utmost importance.
In this chapter, a review of the numerical tools and experimental methods that can
be used to model and assess the interaction of mobile communication devices with
the human body is presented. Regarding dosimetry studies on mobile communication
devices, the interaction between cellular phones and the user’s head has been extensively studied so far. Research assessing the interaction between wired and wireless
(Bluetooth) hands-free devices and the user’s head and body have also been performed.
Furthermore, there is an increased scientific interest in assessing human exposure to
base-station antennas and new emerging communication technologies, such as Wi-Fi,
because of the simultaneous and long-lasting exposure of users. The results of recent
dosimetry studies related to human exposure to cellular phones, wired and wireless
(Bluetooth) hands-free devices, base-station antennas, and Wi-Fi systems are also
discussed.
5.2 Numerical Dosimetry
Numerical dosimetry was first performed in the 1960s, as a means to assess human
exposure to the RF EM fields present, at that time, in the environment, such as fields
produced by radio and TV broadcasting antennas and radar systems. The EM source
was assumed to be placed far from the exposed human body and was represented by a
plane wave (Dimbylow and Gandhi 1991; Gandhi et al. 1992).
Nowadays, numerical dosimetry is widely used to evaluate the interaction between
the EM energy emitted by mobile communication devices and the human tissues. This
interaction is assessed in terms of the derived dosimetric quantities of SAR and current
density and/or the electric and magnetic field induced in the human tissues. Human
exposure to both the near- and far-field of the EM source can be examined. Analytical
methods can be applied to simplified canonical geometries modeling the human body
(or parts of it). On the other hand, numerical methods use body models ranging from
very simple homogeneous models to millimeter resolution anatomic models, with the
latter providing very fine dosimetric results.
5.2.1 Body Models
5.2.1.1 Canonical Models
Basic characteristics of the absorption of RF energy in the human body have been established by homogeneous or heterogeneous (layered) simplified canonical models such as
a cube, a sphere, and a spheroid. Those have been systematically summarized (Durney,
Massoudi, and Iskander 1986) and used for the rationale of RF safety guidelines.
Whole-body canonical models have largely been used in the literature to model the
human body in dosimetry studies. A planar three-layer body model, consisting of a
Mobile Communication Fields in Biological Systems
of the population, and statistical recording of illnesses and symptoms, research on the
biological effects of RF EM radiation emitted by mobile communication devices can
also be carried out numerically and experimentally. Selecting the appropriate methods
for numerical and experimental dosimetry and performing uncertainty assessment to
validate the derived results are of utmost importance.
In this chapter, a review of the numerical tools and experimental methods that can
be used to model and assess the interaction of mobile communication devices with
the human body is presented. Regarding dosimetry studies on mobile communication
devices, the interaction between cellular phones and the user’s head has been extensively studied so far. Research assessing the interaction between wired and wireless
(Bluetooth) hands-free devices and the user’s head and body have also been performed.
Furthermore, there is an increased scientific interest in assessing human exposure to
base-station antennas and new emerging communication technologies, such as Wi-Fi,
because of the simultaneous and long-lasting exposure of users. The results of recent
dosimetry studies related to human exposure to cellular phones, wired and wireless
(Bluetooth) hands-free devices, base-station antennas, and Wi-Fi systems are also
discussed.
5.2 Numerical Dosimetry
Numerical dosimetry was first performed in the 1960s, as a means to assess human
exposure to the RF EM fields present, at that time, in the environment, such as fields
produced by radio and TV broadcasting antennas and radar systems. The EM source
was assumed to be placed far from the exposed human body and was represented by a
plane wave (Dimbylow and Gandhi 1991; Gandhi et al. 1992).
Nowadays, numerical dosimetry is widely used to evaluate the interaction between
the EM energy emitted by mobile communication devices and the human tissues. This
interaction is assessed in terms of the derived dosimetric quantities of SAR and current
density and/or the electric and magnetic field induced in the human tissues. Human
exposure to both the near- and far-field of the EM source can be examined. Analytical
methods can be applied to simplified canonical geometries modeling the human body
(or parts of it). On the other hand, numerical methods use body models ranging from
very simple homogeneous models to millimeter resolution anatomic models, with the
latter providing very fine dosimetric results.
5.2.1 Body Models
5.2.1.1 Canonical Models
Basic characteristics of the absorption of RF energy in the human body have been established by homogeneous or heterogeneous (layered) simplified canonical models such as
a cube, a sphere, and a spheroid. Those have been systematically summarized (Durney,
Massoudi, and Iskander 1986) and used for the rationale of RF safety guidelines.
Whole-body canonical models have largely been used in the literature to model the
human body in dosimetry studies. A planar three-layer body model, consisting of a