Radiation analysis in the space domain of laterally-shielded planar transmission lines

A study was conducted on the propagation and radiation characteristics of Leaky-wave modes in laterally-shielded planar waveguides by using a novel approach based on the Space Domain PPW modes expansion. This method introduces the discrete parallel plate waveguide (PPW) propagation and radiation spectrums for each leaky-wave mode, and allows a direct interpretation of the radiation phenomena by a superposition of modal PPW radiated fields. Results obtained for a laterally-shielded top-open suspended microstrip waveguide, but this method was extensible to any laterally-shielded multilayered and multiconductor open waveguide.