Radiation Losses of the Dominant Mode in Round Dielectric Waveguides

A series of earlier papers was devoted to radiation losses of TE and TM modes in dielectric slab waveguides. 1-3 The radiation losses were assumed to be caused either by random perturbations of the waveguide boundary 1 or by steps and tapers of the slab waveguide. 3 Experiments to verify the radiation loss theory were conducted with millimeter waves in round teflon rods, and the theory was extended to cover this case.2 These earlier publications were limited to the simplified case of 1665 1674 T H E BELL SYSTEM T E C H N I C A L . J O U R N A L , OCTOBER ]f)70 electromagnetic fields that are independent of one coordinate. In the case of the slab waveguide we assumed (1)