The new design of miniaturized dual-band 180° hybrid-ring coupler

A dual-band hybrid-ring coupler made-fed by microstrip lines was designed based on the cyclic characteristic of hybrid-race conventional form. Using compact folded and coupled transmission lines, the model was miniaturized and the bandwidth was significantly broaden. The design idea is hoped to be applied for dual-band. Then measurement result was presented. It can be kept a perfect consistency with the simulation result.