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Correlation between peak spatial-average SAR and temperature increase due to antennas attached to human trunk
Akimasa Hirata1, Osamu Fujiwara, Toshiyuki Shiozawa
1Department of Electrical and Computer Engineering, Nagoya Institute of Technology, Aichi, Japan. ahirata@nitech.ac.jp
IEEE Transactions on Bio-Medical Engineering
|August 19, 2006
Summary
This study reveals that blood flow significantly impacts the relationship between radiofrequency energy absorption (SAR) and tissue heating in the human trunk. Understanding this correlation is vital for mobile device safety assessments.
Area of Science:
- Electromagnetics and Bio-effects
- Thermal Modeling
- Human Body Simulation
Background:
- Occupational communication devices operating at 150, 400, and 900 MHz are attached to the human trunk.
- Assessing the thermal effects of radiofrequency (RF) energy absorption is crucial for safety.
Purpose of the Study:
- To investigate the correlation between peak spatial-average specific absorption rate (SAR) and maximum temperature increase in human trunk tissues.
- To identify key factors influencing this SAR-temperature relationship.
Main Methods:
- Utilized Green's function for detailed analysis.
- Employed a one-dimensional model to study thermal constant variations.
- Validated findings with a three-dimensional realistic human body model.
Main Results:
- Blood flow in tissues emerged as a dominant factor affecting the SAR-temperature correlation.
- The study quantified uncertainties related to SAR calculation and body model geometry.
Conclusions:
- Tissue blood flow is a critical parameter in predicting RF-induced temperature rise.
- Accurate modeling and consideration of physiological factors are essential for robust safety evaluations of RF devices.
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