Parametric interpolation of the moment matrix in surface integral equation formulation
In the analysis of electromagnetic scattering and radiation from objects of arbitrary shape using the method of moments (MoM), it is desirable to fill the impedance (or moment) matrix efficiently so that larger size problems can be solved. This article describes a general MoM technique in which the matrix is filled by spatial interpolation with respect to a parametrized electrical separation between source and test elements. The parametrization is accomplished such that the same algorithm also provides frequency interpolation, thus facilitating efficient computations over a wide frequency band. The spatial interpolation method is illustrated by application to the analysis of radiation from tunable microstrip patch antennas over multiple frequency bands. By specializing the interpolation scheme to a surface integral equation formulation that employs rooftop basis functions on a grid of rectangular cells, it is shown that the interpolation method results in considerable reduction of the storage and CPU time requirements. (C) 1999 John Wiley & Sons, Inc.
method of moments electromagnetic analysis electric field integral equation matrix fill matrix spatial interpolation