Reconfigurable Bandpass Filter with Extracted Pole and Coupling Resonators

This paper presents a reconfigurable bandpass filter with an extracted pole section in the Ku-band. The filter’s center frequency and bandwidth can be controlled independently from each other by using additional resonators. The center frequency can be varied between 13.8 GHz and 14.8 GHz while the bandwidth can be varied between 100 MHz and 200 MHz in the given center frequency range. The extracted pole section provides a transmission zero close to the passband, which increases the selectivity and remains in place relative to the passband during all tuning states.