Radiation from Curved Dielectric Slabs and Fibers

The form taken by the radiation condition in the local coordinate system, pertinent to the determination by perturbation methods of the radiation from curved radiating structures, is not the same as it is at very great distances. Specifically, it may contain a term that appears as if it were an incoming or growing wave. A detailed analysis is made of the appropriate form of the condition in cylindrical and toroidal systems, and is applied to the calculation of radiation from curyed dielectric slabs and fibers.