recherche & développement Exposition des personnes aux ondes électromagnétiques: le défi de la variabilité et l’apport des statistiques en dosimétrie numérique J Wiart, E Conil, A Hadjem, A Gati, MF Wong, N Varsier, A Gahmni, O Auiaz, Th Kientega, A El Habachi http://whist.institut-telecom.fr/
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recherche & développement
Exposition des personnes aux ondes électromagnétiques: le défi de la variabilité et l’apport des statistiques en dosimétrie numérique
J Wiart, E Conil, A Hadjem, A Gati, MF Wong,N Varsier, A Gahmni, O Auiaz, Th Kientega, A El Habachi
http://whist.institut-telecom.fr/
recherche & développement
Dosimetry basic
Exposure assessment.
Complexity management
conclusion
Summary
recherche & développement
Wireless Ubiquous world facing schizophrenia
More than 5 billions users…More than 50 millions in France…
Limits have been established by Exposure assessment is a key question
Eg Le Monde this week: « Ces ondes qui planent sur la tête de nos enfants »
Dielectric properties are tissue and frequency dependant
recherche & développement
Example of absorption in head tissuesHandset operating at
900 MHz
900 MHz 1800 MHz 2100 MHz
recherche & développement
Absorption depends on the shape
The incident EM field is reflected and absorbed.
Reflection and absorption depend on the tissues composition but also on the shape.
Total absorbed power divided by the weight
Large Variability
E
H
E
H
"v"
"H "
2.1 GHz
recherche & développement
Vertical polarization vs Horizontal..
2100 MHz
E
H
E
H
"v"
"H"
Absorption depends also on the polarisation and the posture
After Dr R P Findlay and Dr P J DimbylowHealth Protection Agency, UK.
recherche & développement
Age dependant human Morphology Head and Body shapes are age dependant
Internal anatomy evolves with age
Skin thickness (mm) vs age
0
0,5
1
1,5
2
2,5
2 - 3 y.o 11- 13 y.o Adult
recherche & développement
Human Anatomical models have been improved
MRI and computers facilities allow to built whole body and head models more and more complex.
Adult male body models
Adult female body models
Child body models
Child head models
International effort to develop models
13 WA (US)
23 WA (MRI)
31 WA (MRI)
recherche & développement
Fetus exposure induced by multiple plane wave
0 50 100 150 200 250 300 3500
0.2
0.4
0.6
0.8
1
1.2
1.4
1.6
1.8
2 x 10-6
Azimuth (degré)
WB
SA
R fo
etus
900MHz1800MHz2450MHz
recherche & développement
EMF and Temperature rise
Solved with Alternating Direction Implicit Method
nevaporatioandconvectionradiatonhhh
lationThermoreguTTCbMétabolismh
fieldEMSAR
DiffusionTktTC
EVACONVRAD
bbf
m
,)(
.
.
)(.
SAR
Rise of temperature due to EMF
HeatingCooling
Metabolism
Blood perfusion
Radiation
Evaporation
Convection
Analysis of the Temperature Increase Linked to the Power Induced by RF Source A Ibrahiem, C. Dale, W. Tabbara and J.Wiart Progress In Electromagnetics Research