DOI: 10.1109/TMTT.2025.3558035   IEEEXplore: https://ieeexplore.ieee.org/document/10971433    

Self-equalized generalized Chebyshev microwave bandpass filters (BPFs) in inline coupled-resonator circuit topologies.

1.5 GHZ and 9.98 GHz for the examples presented

Chebyshev microwave bandpass filters (BPFs) can be realized as frequency-variant reactive coupling (FVRC) networks with double-zero single-pole (DZSP) characteristics. With zeros positioned on the imaginary axis for selectivity enhancement or as a pair of real zeros for in-band group delay equalization, microwave BPFs with in-band equi-ripple-type response and close-to-passband transmission zeros (TZs) can be designed entirely with inline topologies – i.e., without cross-coupling.

Self-equalized Chebyshev microwave bandpass filters (BPFs) with flattened group delay, sharp rejection, in-band equi-ripple-type response and close-to-passband transmission zeros (TZs).

Self-equalized 5th-order BPF with 2 imaginary TZs and 2 complex zeros – at 1.5 GHz (microstrip circuit), realized with 4 resonators, 3 frequency-variant couplings, 2 constant couplings, and 0 cross couplings; at 9.98 GHz (waveguide structure), realized with 3 resonators, 2 frequency-variant couplings, 2 constant couplings, and 0 cross couplings.