ABSTRACT
Metamaterial transmission lines were recently introduced as structures supporting left-hand (LH) propagation in addition to the conventional right-hand propagation. Realizations and applications for composite right-/left-handed transmission lines were surveyed. Examining the LH propagation phenomena in these structures is thus in order. Periodically loaded rectangular waveguides were shown to exhibit backward-wave propagation. Conventionally, corrugated waveguides have been used in horn antenna applications, where the corrugated surface serves as a high-impedance surface required to support hybrid modes that improve the radiation characteristics. To accommodate LH propagating waves, the equivalent circuit model of the waveguide should be of the form depicted. A more rigorous analysis technique may be sought by solving the source-free problem of propagation in the corrugated waveguide. If only one wall of the waveguide is corrugated, enforcing the asymptotic corrugation boundary conditions yields a dispersion relation that can be viewed again as a transverse resonance phenomenon.
