A novel branch-line coupler based on the composite right/left handed TL structure

Abstract

In this paper, a new branch-line coupler (BLC) is designed, which is based on the composite right/left handed transmission line structure first proposed by Itoh and Caloz. Both the theoretical analysis and the simulation results are presented in this paper. It is shown that the dimensions of CRLH-based hybrid coupler are much smaller than those of the conventional counterpart, which may find important applications in the design of microwave and millimeter wave integrated circuits.