Simple and Accurate Expression for the Dominant Mode Properties of Open Groove Guide

Groove guide, one of several low-loss waveguides proposed some years ago for use at millimeter wavelengths, is again receiving attention in the literature. A new transverse equivalent network and dispersion relation for the properties of the dominant mode are presented here which are extremely simple in form and yet very accurate. Comparisons with accurate published measurements indicate better agreement with this new theory than with any previous theory.