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GAUSSIAN BEAM MODELING OF SAR ENHANCEMENT IN PARAXIAL AND NON-PARAXIAL REGIONS OF BIOLOGICAL TISSUES

By M. L. Lumori

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Abstract:
A polarized 3D-electromagnetic wave propagating from an aperture source into a lossy medium can be modeled by an astigmatic Gaussian beam model (GBM) of complex source coefficients that characterize a radiating antenna uniquely. The source coefficients are determined numerically from phantom experiments, and then used in simulations of specific absorption rates (SAR), in both homogeneous and layered biological media, resulting in good agreement with experimental data. This paper shows that for an x-polarized E-field the GBM simulations of SAR enhancement or focus in the axial, z-directed, paraxial region are accurate, but approximate in the transverse, y-directed, non-paraxial regions due to a focal shift.

Citation:
M. L. Lumori, "Gaussian Beam Modeling of SAR Enhancement in Paraxial and Non-Paraxial Regions of Biological Tissues," Progress In Electromagnetics Research M, Vol. 11, 1-12, 2010.
doi:10.2528/PIERM09121808

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