Specific Absorption Rate (SAR) Numerical Evaluation: a Critical Discussion

The numerical evaluation of the specific absorption rate (SAR) is a critical task when evaluating human exposure to electromagnetic (EM) fields. Nevertheless, SAR calculation is strongly influenced by many factors as, for instance, the shape of the volume containing the reference mass, the space discretization step or the treatment of internal air (just to mention some of them): different choices can induce significant discrepancies. In this work an overview on some SAR algorithms is firstly presented, and a discussion on their potential differences reported. Then, such algorithms and some new ones proposed by the authors, are used to evaluate the SAR in artificially generated case tests and in some practical human-antenna interaction cases. The remarkable differences highlighted from the comparison, enforce the necessity to individuate a "canonical" algorithm, as discussed in conclusion.