Planar Branch-Line Coupler for 5G Communication

One of the essential components of many microwave circuits is the branch-line coupler (BLC). In this work, a BLC using apertures and shorting post is investigated to obtain a broad-band response characteristic. A delay line has also been introduced to maintain its phase response. The structure operates in a frequency range of 3.3–3.67 GHz with a 370 MHz bandwidth, which is suitable for upcoming n78 5G communications. In this dedicated frequency band, the BLC shows good matching with lower reflection and isolation, stable coupling, and phase difference. The simulation has been carried out using HFSS simulation software.