Design and Implementation of a directional coupler with high directivity using Branch Line Structure

Branch-Line 구조를 이용한 높은 방향성을 가지는 결합기 설계 및 제작

In this paper, we designed and implemented a 10dB directional coupler with high directivity using branch line structure. The characteristic impedance of parallel branch line for 10 dB directional coupler is about 150 $\Omega$. To realize high characteristic impedance in microstrip line, we used the coupled line structure. The directional coupler were implemental and measured. The measured results show that the directivity is high than 24 dB.