A Balanced-to-Unbalanced Hybrid Ring With Arbitrary Power Division Ratio

This paper presents a new balanced-to-unbalanced (BTU) hybrid ring with arbitrary power division ratio. Standard S-parameters and mixed-mode S-parameters are adopted to describe the performance requirements of the BTU hybrid ring. A simple configuration composed of transmission lines is developed to achieve desired functions of the BTU hybrid ring with arbitrary power division ratio. The design equations are given to guide the design. A prototype with the power division ratio of 3:1 is designed to verify the theoretical prediction. The fabricated BTU hybrid ring is matched well for both balanced and unbalanced ports. The BTU power division with arbitrary power division ratio and high mode conversion suppression are also achieved.