Multi-Way Coaxial-Resonator Filtering Power Divider With Controllable Power Division Ratios

We propose multi-way filtering power dividers (FPDs) using coaxial resonators with controllable power division ratios. By tap-connecting the feeding probe to the coaxial resonator, the external quality factor is controlled flexibly by adjusting locations of feeding probes. Thus, this structure can be used as the impedance inverter with controllable impedance transformation ratios, which can overcome the fabrication limitation of the conventional quarter-wavelength impedance inverter with high characteristic impedances. Based on the coaxial resonators, a circuit topology for designing a multi-way FPD is proposed. Only two coaxial resonators and multiple feeding probes are required to realize a 2
^nd
-order FPD with the arbitrary power division ratio, resulting in a simple structure and a compact size. For verification, three design examples with different output channels and power division ratios are presented, showing good filtering responses and power division performance.