Complex image green's functions of antenna radiating near a human head

Abstract

The recent global spread of mobile phones has caused wide concern among the scientific community and population about the possibility of health hazards caused by EM radiation from these phones. A parameter of particular importance in this subject is the “Specific Absorption Rate (SAR)”, defined as the rate of energy absorption per unit mass of human tissue. To find the fields, and hence the SAR, several techniques have been used. Some techniques are complicated such as using MRI to produce a model for the human head, and then finding the fields inside this model using FDTD, FE, or TLM methods. A simpler technique was used by Akram et al [1], who proposed a simple human head model that consists of 6 layers of tissue with each layer having different conductivity and dielectric constant. This model was used in [1] to find the SAR inside a human head illuminated by a normally incident plan wave. Later, Omar et al. [2] extended the work of [1] to the more general case of plane wave obliquely incident on the human head. Omar [2] also showed that the use of planar multilayered head model produces SAR values that are in good agreement with those obtained assuming a spherical multilayered head model.