Use of fractional operator to define intermediate zones in electromagnetics via Dirichlet Green's function

The principal goal of this paper is to investigate the intermediate zones in electromagnetics when a radiation/scattering problem is modeled through Dirichlet Green's function. Field/potential quantities over two parallel observation flat planes are related by an integral transform with K as its kernel. The kernel of the integral transform may be divided into two parts: one is Km yielding contribution due to actual source and the other is Kn yielding image contribution. The fractional kernel Kν with fractional parameter ν can provide a unique way of interpreting the field in the intermediate zone. Moreover, use of this fractional kernel to study the Fresnel and Fraunhofer diffraction zones is also described. Result for corresponding static problem is obtained by applying the limit on this kernel.