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We present a variant of a boundary integral equation proposed by M. Herberthson in 2008–2010 for high-frequency plane wave scattering by perfectly conducting obstacles. This integral equation, as some of its predecessors, is entirely dedicated to a single direction of incidence. A significant reduction in the system size can then be obtained by looking for a pseudo-current, which is the actual surface current multiplied by the conjugate of the incident wave’s phase function. This advantage is mostly lost when multiincidence problems have to be solved because, in addition to the source terms, the discretized operator must be recomputed for every new incidence. In this article, we make an explicit representation of the new operator as the sum of a conventional electric field integral equation (EFIE) which is independent of the direction of incidence, and an additional operator, which is dependent on the direction of incidence. The latter can be computed very efficiently such that a net performance gain is obtained with respect to the EFIE even for multiincidence problems. [ABSTRACT FROM AUTHOR]

This article presents a method to characterize stochastic observables defined by induced surface currents and fields in electromagnetic interactions with uncertain configurations. As the covariance operators of the stochastic distributions and fields are not compact, a strict Karhunen-Loève (KL) approach is not possible. Instead, we apply a point-spectrum regularization by expanding the stochastic quantities on a finite-element-like basis. The coefficients of the KL expansion are approximated analytically in a polynomial-chaos (PC) expansion. The novelty of our approach resides in its ability to handle multiple PC expansions simultaneously and determine the orders of the KL and PC expansions adaptively. This method is illustrated through the example of the voltage induced at the port of a random thin-wire frame illuminated by random plane waves. The results show the accuracy and computational efficiency of the proposed method, which provides a complete characterization of the randomness of the observable. [ABSTRACT FROM AUTHOR]

A stochastic method is proposed to characterize electromagnetic couplings involving geometrically perturbed transmission lines. A combined exploitation of suitably defined statistical tools is presented to appreciate the intensity of the dispersion of response variables both physically via the variance, and statistically through the kurtosis or fourth-order moment. The usefulness of this method to analyze resonances is illustrated by the study of a transmission line affected by two different types of random geometrical perturbations, viz. a local deformation modeled by a wavelet and global sinusoidal undulations. [ABSTRACT FROM AUTHOR]