Switchable Microstrip Bandpass Filters With Reconfigurable On-State Frequency Responses

A switchable microstrip bandpass filter (BPF) with reconfigurable on-state frequency responses is proposed. The filter consists of a two-pole BPF and two switchable delay lines. The proposed filter features not only switch ability with an on-off ratio of 41.2 dB but also two on-state frequency responses: Chebyshev response and quasi-elliptic-function response. Experiment was carried out to validate the design concept, and the simulation agrees well with the measurement.