ABSTRACT
This chapter presents an account of electromagnetic (EM) interactions in biological media, with special emphasis on the energy coupling and distribution characteristics in biological structures. It outlines a number of techniques that have been successfully employed to analyze the propagation and absorption characteristics of EM energy in tissue structures. There are two general approaches: one involves extensive use of analytical development and the other relies more heavily on numerical formulation. The chapter examines in some detail the correlation between specific absorption rate (SAR) and temperature increase for a human body exposed to both near-field radiofrequency (RF) sources and far-field plane waves as functions of exposure duration, different tissue size, and schemes for averaging metrics, including description of volumetric absorption rate (VAR) in addition to SAR as a dosimetry metric. It also presents the computational algorithms based on numerical techniques applied to predict EM field strengthens and SAR distributions in anatomically realistic models of human and animal bodies.
