Parametric analysis of multi section slot coupled quadrature coupler

This paper presents a design procedure of an ultra wideband three section slot coupled hybrid coupler employing a parametric analysis of different design parameters. The coupler configuration is composed of a modified hexagonal shape at the top and bottom conductor plane along with a hexagonal slot at the common ground plane. The coupler performance for different design parameters is studied through full wave simulations. A final design providing a return loss and isolation better than 20dB, an amplitude imbalance between output ports of less than 0.9dB and a phase imbalance of ±1.9° across the 3.1-10.6 GHz band is confirmed.