A new sectioning procedure for calculating scattering and absorption by elongated dielectric objects

The iterative extended boundary condition method (IEBCM) has recently been developed to calculate scattering and absorption by elongated dielectric objects. The authors present a new sectioning procedure to improve the computational efficiency of the IEBCM. In this technique, the total geometry of the object is divided into overlapping sections, each of which includes only 3-5 spherical expansions to describe the internal fields. The total number of expansions required to describe the internal fields in the overall object may be as large as 15. Results illustrating the improvement in the computational efficiency of the IEBCM, as well as the dependence of the minimum number of expansions that should be included in each section on the dielectric properties of the scatter and on the frequency, are presented. It is shown that the sectioning procedure is particularly useful at frequencies below (ka<3) and above the resonance frequency of the object (4>