On the Dual Basis for Solving Electromagnetic Surface Integral Equations

• Published in: IEEE transactions on antennas and propagation Vol. 57; no. 10; pp. 3136 - 3146
• Main Authors: Mei Song Tong, Weng Cho Chew, Rubin, B.J., Morsey, J.D., Lijun Jiang
• Format: Journal Article
• Language: English
• Published: New York, NY IEEE 01.10.2009; Institute of Electrical and Electronics Engineers; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: Analytical models; Antennas; Applied classical electromagnetism; Applied sciences; Basis functions; Computational efficiency; Current; Diffraction, scattering, reflection; electromagnetic (EM) scattering; Electromagnetic fields; Electromagnetic scattering; Electromagnetic wave propagation, radiowave propagation; Electromagnetism; electron and ion optics; Exact sciences and technology; Fundamental areas of phenomenology (including applications); Generalized method of moments; integral equation; Integral equations; Magnetic analysis; Mathematical analysis; Mathematical models; Moment methods; Nonuniform electric fields; Numerical stability; Orthogonality; Physics; Radiocommunications; Radiowave propagation; Scattering; Studies; Telecommunications; Telecommunications and information theory; Vectors (mathematics); Electromagnetic wave scattering; Electromagnetism; Electromagnetic wave propagation; Basis functions; electromagnetic (EM) scattering; moment methods; Wave scattering; Moment method; Integral equation; Orthogonality; Computational complexity; Numerical stability
• ISSN: 0018-926X; 1558-2221
• DOI: 10.1109/TAP.2009.2028622

A powerful technique for solving electromagnetic (EM) surface integral equations (SIEs) for inhomogenous objects by the method of moments (MoM) involves the well-known Rao-Wilton-Glisson (RWG) basis function to represent the electric current and, for field orthogonality and numerical stability reasons, a variation of the RWG basis known as the ntilde X RWG basis (where ntilde is a unit normal vector at the object surface) to represent the magnetic current. Though this combination provides a numerically efficient and effective solution that has been demonstrated on a variety of structures, one cannot feel entirely comfortable because of the presence of fictitious magnetic current associated with the modified basis. Chen and Wilton proposed a different, smoother basis in 1990 that avoids the fictitious line charges, but because of computational cost issues it has not been used beyond Chen's dissertation. Recently, this basis was rediscovered and has received considerable attention. Our work reexamines the dual basis, exploring issues not addressed by Chen and Wilton and showing accurate solutions for a variety of EM scattering structures.