Efficient electromagnetic analysis for curved open thin-wire structures using intervallic wavelets in the method of moments

Abstract

Efficient electromagnetic (EM) analysis for curved open thin-wire structures is developed by solving integral equations with intervallic wavelets in the method of moments (MoM). The electrical field integral equation for curved thin-wire structures is formulated based on the generalized Pocklington integral equation and the unknown current is expanded using the intervallic Coifman father wavelets as basis functions. In the current representation, an appropriate geometric map is established between thin-wire segments and bounded intervallic wavelets to match different domains. Since the Coifman wavelets (Coiflets) possess a unique feature, i.e. the vanishing moments which can yield a Dirac-δ-like sampling property, they are used to construct the intervallic wavelets. Also, the corresponding edge basis functions are built to represent the unknown current in the edge intervals for open structures. By using the intervallic wavelets in the MoM and performing a fast wavelet transform, sparse impedance matrices can be obtained and the drawbacks of dense matrices are overcome. Numerical examples for analyzing the scattering or radiation properties in different thin-wire structures are presented to demonstrate the robustness of the intervallic wavelets.