Introducing new design guidelines for dualband CRLH structures formed by transmission lines and lumped components

In this paper a new strategy for designing dualband composite right and left handed (CRLH) structures based on lumped elements is introduced. By using the presented formulars the desired metamaterial devices become easily scalable to arbitrary frequencies as the parasitic elements of the lumped components are considered resulting in three design guidelines. The practical use is shown by a dualband branch line coupler and a Wilkinson power divider operating at 2.5 GHz and 5.25 GHz.