Study of time normalization for TD-AEFIE at low frequencies

In this paper, the time normalization for the time-domain augmented electric field integral equation (TD-AEFIE) is studied. Because of the introduced current continuity equation and the inherited convergence issue in the frequency domain, the marching on-in-time (MOT) system matrix is also ill-conditioned. After applying a time-domain preconditioner, the iterative system converges faster than the traditional matrix system. For different kinds of time normalized systems, the convergences with different time steps are investigated. Numerical results for the transient scattering problems demonstrate the stability and accuracy of the preconditioned systems.