Propagation behavior in rectangular metallic waveguide periodically loaded with single negative metamaterial slabs

This paper focused on propagation characteristics of a single mode supporting waveguide enclosed by metallic sidewalls periodically loaded with lossless single negative (SNG) metamaterial slabs along axial direction. The gap between two successive SNG slabs is filled with a double positive (DPS) material. For the analysis, the periodic structure is assumed having symmetric unit cell (UC) and simplified as a two-port network which is one-half of the symmetric UC. Scattering parameters (S-parameters) are defined by even/odd mode analysis of the symmetric UC, and then the total S-parameters are calculated by solving the cascade connection of N unit cells. Eigenvalue equations are also obtained to explicit the solutions of band edge and pass/stopband diagrams in the microwave regime. Since a SNG can be either epsilon-negative (ENG) or mu-negative (MNG), S-parameters and dispersion behavior are illustrated with numerical examples and discussed for each periodic structure constructed with ENG or MNG slabs.