T3P is a 3D parallel finite-element time-domain solver to         calculate transient field response of a electromagnetic         structure to imposed fields, and dipole or beam         excitations.

In our approach, Ampere's and Faraday's laws are combined and integrated over time to yield inhomogeneous vector wave equation for the time integral of the electric field *E*:

{latex}\begin{eqnarray*}
\left( \epsilon \frac{\partial^2}{\partial t^2} + \sigma_{eff} \frac{\partial}{\partial t} + \nabla \times \mu^{-1}\nabla\times \right) \int^t \emph{E} d \tau = -\emph{J}
\end{eqnarray*}
{latex}with permittivity {latex}
\epsilon = \epsilon_0 \epsilon_r
{latex} and permeability {latex}
\mu = \mu_0 \mu_r
{latex} .