Comb filter

The utility model relates to a comb filter, multimode resonator transfers comb filter's frequency of operation to corresponding frequency to make the spurious frequency keep away from required frequency of operation, supplementary coupling piece is used for changing the coupling path's between the multimode resonator coupling strength. Adopted the utility model discloses a comb filter, comb filter's through the design multimode resonator's high impedance section and the electrical length and the impedance ratio of low impedance section, the high order mode of resonance that can adjust the syntonizer distributes, thereby make comb filter's passband frequency keep away from high parasitic resonant frequency, through the distance between the design multimode resonator and the form of supplementary coupling piece, can change two coupling path's of multimode resonator coupling strength, thereby obtain required bandwidth, multimode resonator's high impedance section part is folded, the volume of wave filter has bee