Bending losses in hollow and dielectric tube leaky waveguides

Abstract

A general method is presented of evaluating bending losses in hollow-core waveguides; analytic expressions are obtained for metallic hollow, dielectric hollow, and tube leaky waveguides on the basis of the 2-D slab waveguide model. Numerical examples are given for waveguides made of different kinds of metals, oxide, and dielectric materials at 10.6 microm. It is shown that the dielectric tube leaky waveguide can be bent with a small bending radius compared with a metallic hollow waveguide when the guide material is appropriately selected.