New Small Size 3 dB 0°/180° Microstrip Coupler Configurations

New small size 3 dB microstrip 0°/180° coupler configurations are proposed and discussed. The coupler can be fabricated in square or ring form. The ring may be designed for symmetrical ports about either one axis or two axes. The proposed configurations introduce significant size reduction, which is the most important demand for microwave integrated circuits (MICs) and monolithic microwave integrated circuits (MMICs). Different couplers are designed, and simulated at 900 MHz. The designed coupler in square shape is simulated and implemented. Experimental results agree quit well with theoretical predictions.Applied Computational Electromagnetics; Montere