Simple Design of Tunable Phase Shifter Using Reconfigurable Coupling Topology

This letter proposes a novel design of tunable phase shifter (PS) with simple circuit structure and small phase error. By creatively studying phase relations between different magnitude responses, filtering magnitude performances with 45° phase jumps are chosen. On this basis, a reconfigurable coupling topology on a shared physical structure is put forward. In this way, the phase design is transformed into the well-established filtering magnitude design. Additionally, continuous phase tuning between states is achieved by tiny adjustments of the operating frequency. A tunable PS using reconfigurable multimode resonator (MMR) is designed, exhibiting a phase shift of 180° with 5.5° phase error covering 0.77–0.83 GHz.