Electromagnetic Pulse Interaction with Mammalian Cranial Structures

The transmitted field strengths in homogeneous spherical models of human and animal heads are determined as a function of time and position, using frequency analytic techniques for an impinging pulse of Gaussian character. A relaxation process and constant conductivity are assumed for the electrical behavior of brain matter. The constant conductivity process predicts continued decrease in pulse amplitude as it advances in the head starting from the leading surface; however, the relaxation process predicts reduction only from the surface to the center. Moreover, it appears that the transmitted pulse in a spherical model of the head is always related to the time derivative of the incident radiation. Numerical results indicate that the transmitted pulse amplitude is quite small and can be estimated using the constant conductivity model.