A note on using dyadic Green´s functions on spheres and cones

The objective of this article is to alert antenna engineers to a possible error that may occur when working with dyadic Green´s functions associated with conical geometries. For example, such problems can arise when designing microstrip antennas on a conical surface, or when dealing with scattering caused by conical geometries. The dyadic Green´s function is a very useful tool for obtaining the interaction of electromagnetic fields with several physical geometries. With this technique, the engineer can formulate various canonical electromagnetic problems in a systematic manner, to avoid having to treat many special cases. However, in dealing with conical geometries, special care must be taken