| 摘要 |
PROBLEM TO BE SOLVED: To provide a band-pass filter that can be tuned quickly with a decreased insertion loss.SOLUTION: An RF filter includes: a signal transmission path having an input and an output; a plurality of resonant elements disposed along the signal transmission path between the input and the output; a plurality of non-resonant elements coupling the resonant elements together to form a stop band having a plurality of transmission zero points corresponding to respective frequencies of the resonant elements, and at least one sub-band between the transmission zero points; and at least one tunable non-resonant element for selectively introducing at least one reflection zero point within the stop band to create a pass band in a selected one of the sub-band(s). The RF filter further includes an electrical controller configured for receiving an operating temperature, and adjusting the tunable non-resonant element(s) on the basis of the received operating temperature, thereby selectively moving the reflection zero point(s) along the stop band to move the pass band within the selected sub-band. |
