The late-time evaluation of electromagnetic (EM) field quantities yielded by convolution integrals that combine Green's functions available at discrete time samples and strictly causal excitations is critically revisited. A typical situation is used for tracing the causes of the divergent late-time behavior that is often experienced. A framework combining a suitable integral partitioning with a polynomial approximation is shown to effectively guarantee the integrals' convergence. The formulation is validated via numerical experiments evidencing its accuracy and computational efficacy. The method is amenable to be used in a wide range of problems requiring the late-time evaluation of convolution integrals of the indicated type.

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The critical relevance of ensuring the excitation's causality in electromagnetic (EM) simulations is exploited by the computation of strictly causal time domain interaction integrals as they occur in the partial element equivalent circuit (PEEC) method. Under the hypothesis of thin, almost zero thickness objects, the presented formulas represent analytical impulse responses and, as such, are used within convolutions in the framework of the time domain PEEC solver. The proposed approach is compared with other standard approaches and clearly behaves better than frequency-domain methods in accurately catching the propagation delay and, thus, preserving the causality. Further, improved stability is observed compared to marching-on-in-time methods..@en

Closed-form time-domain (TD) analytical expressions describing the electromagnetic (EM) signal transfer between two vertical dipoles through a thin, highly contrasting layer with combined magneto-dielectric properties are derived via the Cagniard–DeHoop (CdH) technique with the TD saltus-type conditions. The TD EM-field coupling between the antennas in the absence of the layer is discussed, including its near-field asymptotic solution. It is demonstrated both analytically and numerically that under certain circumstances the combined sheet behaves virtually as a transparent sheet the transition across which inverts the polarity of the received signal.@en

Pulsed electromagnetic (EM) scattering from a relatively narrow superconducting strip is analyzed with the aid of the EM reciprocity theorem and the Cagniard-DeHoop (CdH) technique. The analysis yields a stable convolution-type equation that is solved using the marching-on-in-time (MOT) technique for coefficients representing the time-domain (TD) electric current induced in the strip. Illustrative numerical examples are validated with the help of the CdH method of moments (CdH-MoM).@en

This article explores some dominant trends in teaching classical electromagnetic (EM) field theory in electrical engineering (EE) undergraduate curricula. The acronym EM will be used interchangeably to designate either electromagnetic or electromagnetism. The intended significance will be evident from the context.

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The pulsed EM-field signal transfer between two co-planar small-loop antennas located on a half-space with dielectric and conductive properties is analyzed analytically with the help of the Cagniard-DeHoop technique and the Schouten-Van der Pol theorem. The analysis yields a closed-form time-domain expression for the open-circuit voltage induced across the ports of the receiving antenna. Limiting cases considering the mutual coupling between two loops placed in free-space and on a dielectric half-space are discussed. The obtained results are validated using analytical expressions for the special cases and with the aid of a 3-D EM computational tool.

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This paper introduces a new paradigm in the electromagnetic (EM) analysis of largely inhomogeneous nanostructures. It is shown that the high degree of inhomogeneity may render the traditional discretisation of such topologies problematic. A new discretisation scheme that is much better matched to these topologies is proposed. The scheme involves a more adequate meshing and discretisation formalism, in conjunction with an original combination of dual space-time EM field quantities to be calculated. The pivotal field equations are elaborately discussed, with an emphasis on their computational implications.

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