The invention discloses a dual-mode
dielectric waveguide filter, and the filter comprises a
dielectric body with a
conductive coating on the surface, wherein the
dielectric body is divided into a plurality of resonant cavities, the top of at least one
resonant cavity is provided with a dual-mode structure, and the dual-mode structure comprises two tuning blind holes and a
coupling through groove.The two tuning blind holes must be punched from the same side of the
dielectric body, the
coupling through groove is located on the perpendicular bisector of the connecting line of the circle centersof the two tuning blind holes, the two blind holes generate a pair of TM210 odd and even
modes, the resonant frequency of the two blind holes is controlled by the depths of the tuning blind holes, andthe
capacitance loading effect of the
resonant cavity is enhanced through the two blind holes; the resonant frequency of the TM210 odd mode and the TM210 even mode is reduced, the TM210 odd mode andthe TM210 even mode become a main mode of a
resonant cavity, the
coupling through groove generates an
inductance effect, magnetic coupling is introduced between the TM210 odd mode and the TM210 even mode, and
electromagnetic coupling resonance is formed together with the two tuning blind holes. According to the invention, two
modes are used in one cavity, so
miniaturization of the resonant cavityand even the filter is realized.