A Rectangular Disk 3 Db Quadrature Hybrid with Flat Coupling

Abstract

A simple-shaped planar-circuittype 3dB quadrature hybrid with very flat coupling is proposed arid examined theoretically and experimentally. This hybrid consists of a four-port rectangular disk with two symmetrical capacitive stubs at its periphery and four identical impedance steps at each port. A relntivt? bandwidth of 27 percent is obtained.