Experimental Study of Compact Uniplanar 90-/180-degree Hybrids

摘要

In this paper, compact 90-/180-degree hybrids that are branch-line and rat-race hybrids designed based on the equivalent admittance approach are realized with a uniplanar structure. The circuits treated here are composed of some capacitors added in series or in parallel with the transmission line, and an ideal phase inverter. Each designed hybrid is about 2/3 and 1/10 smaller than the conventional hybrids. Their effectiveness is confirmed by electromagnetic simulations and trial experiments in the design frequency of 2.45 GHz.