Numerical integration methods

The numerical evaluation of an integral is a frequently encountered problem in electromagnetic theory. This is particularly the case when the current distribution or near field of a scatterer or antenna is required, in which case the far-field approximation cannot be employed. A comparative study of several numerical quadrature techniques is presented. The superiority of a variable interval-width technique based on Romberg´s method will be demonstrated for an integral typical of those which arise in scattering and radiation from thin-wire structures.