Efficient technique for mutual coupling calculations between apertures on a PEC circular cylinder covered with a dielectric layer

An efficient and accurate asymptotic Green's function is developed, which will be used to calculate the surface fields excited by tangential magnetic sources on the surface of a PEC circular cylinder that is covered with a dielectric layer. With this knowledge it is possible to calculate the mutual coupling between waveguide fed apertures located on the PEC surface. Note that the efficiency and accuracy of the method strongly depends on the computation of the Green's function.