A novel 180° hybrid ring coupler proposal and realization

The 180° hybrid coupler are among the most fundamental building blocks in radio frequency circuits and microwave integrated circuits. These couplers can be found in many applications, including dividers and combiners, modulators and demodulators, balanced mixers, balanced power amplifiers and in the feed network of antenna arrays. The 180° hybrid couplers exhibit some advantages, such as its simple design methodology and a high degree of isolation between the input ports. It also has serious drawbacks, such as a relatively narrow bandwidth and a large occupied area. In this paper a novel hybrid coupler was proposed to cure the problems of conventional hybrid ring coupler such as narrow bandwidth and large area consumption. The main idea of the proposed hybrid coupler is suspended microstrip line. First the proposed hybrid coupler was designed, simulated, realized and measured. As result, proposed hybrid coupler has more bandwidth and smaller than conventional hybrid ring coupler.