Disclosed in the present invention is a quad-mode defected ground structure resonator-based triple-passband filter structure, comprising a PCB dielectric board, a quad-mode defected ground structure resonator, and two microstrip feed lines. The quad-mode defected ground structure resonator comprises a first resonant cell and four second resonant cells; one end of each of the four second resonant cells is connected to one of four ends of the first resonant cell, respectively; front ends of the microstrip feed lines separately extend to an edge of the PCB dielectric board; tail ends of the two microstrip feed lines respectively extend from two fourth slot lines at the same side of a first slot line to a first central axis and terminate near a closed end of the second resonant cell; the two microstrip feed lines are symmetric about the first central axis; the distance between the tail ends of the two microstrip feed lines are shortened to form a source-load coupling feed structure; the feed structure forms four transmission zeros, to form the triple-passband filter structure. According to the triple-passband filter structure in the present invention, three basic transmission passbands are generated, high passband selectivity is provided without increasing the number of resonators, and the size of the structure is reduced.
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