Characteristic Spherical Wave Expansion With Application to Scattering and Radiation Problems

The aim of this letter is to present the creation of a new set of harmonics based on spherical waves (SWs). They are generated depending on the elements under analysis in an analogous way to the one employed in the generation of characteristic basis functions. The new set of waves enables us to model the fields radiated or scattered by an element in a more efficient way. As an example, we apply this expansion to reduce the number of unknowns when analyzing multiple elements in both scattering and radiation problems. Results show a very good agreement with reference results and with measurement from the open literature.