Design Guidelines and Applications for Dual-Band Rat-Race Couplers and Gysel Power Dividers With Unequal Amplitude Imbalances [Application Notes]

Couplers and power dividers are integral parts of many microwave systems and subsystems. Sometimes, these components are referred to as signal-separating structures because they separate the input signals into two output signals with different power labels and phase delays. In-phase/out-of-phase couplers [rat-race couplers (RRCs)] and Gysel power dividers (GPDs) are two popular components because of their wide bandwidth and unequal power division flexibility. Here, we will show that the same design equations can be utilized to design both components.