Dipole models for the far-field representation of EMP simulators with application to estimates of human RF exposure

The authors present dipole modeling techniques which are useful for calculations of far fields from vertically or horizontally polarized electromagnetic pulse (EMP) simulators. Vertically polarized simulators are modeled with a single dipole above a finitely conducting half-space. Three dipoles were used in the case of a horizontally polarized simulator. Effects of soil models with both frequency-dependent and frequency-independent values for soil conductivity and dielectric constant are included in the study. Calculations with dipole models compare reasonably well with measurements conducted at the AESOP facility and finite-difference calculations of free fields near the VEMPS II simulator. Integrals of the Poynting vector are used to obtain an upper limit for whole body specific absorption in a prolate spheroidal human model. The results suggest that EMP simulator thermal effects at the cellular level are small in comparison to random thermal agitation