The pulsed electromagnetic (EM) field transfer between a horizontal electric dipole (HED) and a transmission line is described analytically with the aid of the time-domain (TD) reciprocity theorem and the Cagniard-de Hoop technique. A suitably chosen wave-slowness representation makes it possible to cast the pertaining interaction integrals into a form amenable to analytical solution. The closed-form coupling model thus obtained clearly reveals the dependence of configurational parameters on the wireless signal transfer. Numerical results are presented and validated using a 3-D EM computational tool.@en

Thin-wire structures in the presence or absence of a ground plane are analyzed numerically in the time domain (TD) with the aid of the Cagniard-DeHoop method of moments (CdH-MoM). It is demonstrated that the TD solution of such problems can be cast into the form of discrete time-convolution equations. Under the assumption of piecewise linear space-time axial current distribution, the elements of the TD impedance array are derived analytically in terms of elementary functions. Their approximations applying to multi-conductor transmission lines are discussed. Illustrative numerical examples validating the TD solution are presented.@en

The transient electromagnetic (EM) excitation of a narrow slot in a perfectly electrically conducting (PEC) screen that separates two homogeneous dielectric halfspaces, a simplified model of a typical feeding structure of leaky lens antennas, is analyzed numerically in the time domain (TD). The problem is formulated using the TD reciprocity theorem of the time-convolution type and subsequently solved with the aid of the Cagniard-DeHoop method of moments (CdH-MoM). Numerical results are validated using a general-purpose EM-field solver.@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

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.@en

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.@en

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

Time-domain (TD) methods for the solution of Maxwell's equations are particularly appealing for their ability to provide the overall characteristics of an electrical system in a single simulation run. In many situations, such TD methods require computing the system's impulse response and using it in a convolution-based solver. In this work, we propose the evaluation of the scattering-parameters-type impulse response of partial element equivalent circuit (PEEC) models by firstly computing the scattering parameters pertaining to a unit-step excitation via the Numerical Inversion of Laplace Transform (NILT) technique, followed by recovering the corresponding impulse response. The accuracy and effectiveness of the advocated approach is validated by means of numerical experiments comparing its performance with that of more standard methods.@en