GUIDED-WAVES ALONG A METAL GRATING ON THE SURFACE OF A GROUNDED DIELECTRIC SLAB

The propagation of guided waves along a metal grating lying on a groun ded dielectric substrate is studied. Hitherto, investigation of the pr operties of such waves has been restricted to directions of propagatio n perpendicular to or nearly parallel to the strips of grating. Averag ed boundary conditions for the fields at the grating are used here to simplify the analysis, and are expected to yield accurate results for grating periods that are sufficiently small compared to a wavelength. Comparisons made with more exact computations in the literature are sh own to be good. The results have potential application for microwave a nd millimeter wave waveguides, slotted microstrip antennas, and circui t elements.