Compact High-Directivity Contra-Directional Coupler

This paper presents a novel design of compact contra-directional coupler with high directivity for high-power monitoring in frequency. Microstrip parallel coupled lines are widely used directional couplers; however, they show poor inherently. Their has been improved by many works. However, the suggested approaches often result other limitations, such as weak structure monitoring, or larger size to be integrated circuits. The approach proposed this study starts from ring-type four-port network avoid components that vulnerable power, and uses 60° electrical length line size. equations initial dimensions derived model. coupling 20 dB was designed measured. measurement shows 12.8 GHz 14.8 GHz, covering Ku-band satellite uplink communication peak about 45 dB. coupler’s active area is 4 mm 5.5 mm; compared