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.
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doi:10.1109/22.869003
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doi:10.1109/22.60008
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doi:10.1088/0031-9155/35/3/007
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doi:10.3109/02656739209021778
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doi:10.1109/10.391168
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doi:10.1029/RS024i004p00433
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19. Ebrahimi-Ganjeh, M. A. and A. R. Attari, "Study of water bolus effect on SAR penetration depth and effective field size for local hyperthermia," Progress In Electromagnetics Research B, Vol. 4, 273-283, 2008.
doi:10.2528/PIERB08011403
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