Generalized Topology and Synthesis Design of Balanced Wideband Phase Shifters With Common-Mode Suppression

This paper proposes the generalized topology and synthesis design method for the wideband balanced phase shifters with common-mode (CM) suppression. By utilizing of the open- and short-circuited stub-loaded T-shaped structure, high CM rejection and good differential-mode (DM) filtering property can be simultaneously achieved. Additionally, the DM amplitude response in reference and main branches can be prescribed for equal-ripple Chebyshev response, and the corresponding DM phase shift and CM rejection level can be synthesized accordingly. As a generalized topology, J inverter and K inverter realized by the coupled line and loaded stub, respectively, are well suited for implementations. The design method has been well verified by two sets of experimental results.