Scattering from an Arbitrarily Located Off-Axis Inhomogeneity in a Step-Index Optical Fiber

An exact analysis using the Green's function formulation of an arbitrarily oriented off-axis dipole radiating into a dielectric rod waveguide is carried out. The method of analysis involves expressing the fields and the current source in a Fourier integral in the zeta-direction and a Fourier series in the phi-direction in a cylindrical coordinate system (rho, phi, zeta). The practical significance of this analysis, in particular with regard to its applications to the problem of scattering from an arbitrarily located inhomogeneity in a step-index optical fiber, is presented.