298
Electromagnetic Fields in Biological Systems
Local SAR max (0.125 W) = f (x)

10

Adult_0 mm
Adult_10 mm
Child_10 mm
Child_0 mm
Local SAR max (W/kg)
1
0,1
0,01
0,001
0,0001
0
2
4
6
8
10
12
14
x (cm)
Figure 5.18 Local SAR variation along the x-axis (ear-to-ear) of anatomical adult and child
head models exposed to a cellular phone with a mounted helical antenna, placed at a distance of
0 or 10 mm away from the head model.
Local SAR max (0.125 W) = f (x)
Local SAR max (W/kg)
10
1
0,1
0,01
0,001
0,0001
Adult −10%
Adult 10%
Child −10%
Child 10%
-
0
2
4
6
8
10
12
14
x (cm)
Figure 5.19 Local SAR variation along the x-axis (ear-to-ear) of anatomical adult and child
head models exposed to a cellular phone with a mounted helical antenna, placed at a distance of
0 mm away from the head model. Dielectric properties variation –10% to 10%.
for realistic exposure scenarios. These trends were respectively less (55%–65%) and more
(up to 24%) emphasized in the corresponding canonical exposure scenarios.
Future parametric studies should further examine different EM sources with varied
relative positioning in the proximity of the head. Multiparametric studies involving variation of dielectric properties along with separation distance and varied positioning of the
cellular phone should also be carried out in order to extend the present studies’ results.
5.4.2 Wired and Wireless (Bluetooth) Hands-Free Devices
Cellular phones are held against the head while a call is made. Typically, the distance
from the antenna to the head is less than 2 cm and the user is in the near-field of the EM
source. Wired and wireless (Bluetooth) hands-free devices enable the cellular phone to
be removed from the head region. However, health concerns do remain.