Comparison of the Specific Absorption Rate in a Homogeneous Man Model and a Man Model Containing Realistic Model Bones

摘要

As part of a study of far-field microwave dosimetry in the human body, local and average specific absorption rates (SARs) in a homogeneous full-size muscle-equivalent upper-body man model were compared with measurements in an upper-body man model also containing simulated skull, brain material, oral and throat cavities, and vertebrae. The measurements were made in the torso and head region at 2.0 GHz with e-polarized irradiation. Qualitative comparisons of front surface temperature were obtained with a thermographic camera. Whole-body SAR was measured with a gradient-layer calorimeter while SAR profiles at the eye and neck locations were measured using a nonperturbing temperature proble. The result of these comparisons showed minor differences in radio frequency (RF) absorption. At this frequency, the freespace wavelength (15 cm) is less than the major body dimensions, and the energy absorption ocurred primarily at the front surface of the model in a fairly unfiorm pattern. We conclude that the interior composition of our man model does not significant affect the over-all absorption characteristics at freuencies where the body dimensions are greater than the irradiation wavelength.