Waveguide input method for time-domain wave propagation algorithms

A waveguide feed method is constructed for time-domain wave propagation algorithms. The concept is to connect a region of homogeneous index of refraction to the waveguide region by a refractive index taper. The first example of this method finds the coupling efficiency for a given input into a waveguide of a particular index geometry. The second example of this method reveals the evolution of the propagation constant through a horn geometry.<
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