A useful transformation of the free-space Green's function with applications to analyses of wire structures

The free-space Green's function of electromagnetics is transformed to a form which simplifies analyses of wire structures. The useful property of the new form is that it enables one to compute the electric field componentE_{s}by applying only (partial^{2}/partial s^{2}) + k^{2}] to a potential integral (with new Green's function) even though such an integral is, in general, to be taken over currents that are nots-directed. It can be shown that the transformation effectively yieldsE_{s}in terms of a TM representation.