Broadband band-pass filter low in insertion loss

Abstract

The invention discloses a broadband band-pass filter low in insertion loss. The broadband band-pass filter comprises a medium substrate, and is characterized in that a first metal patch is arranged on the upper surface of the medium substrate, and a second metal patch is arranged on the lower surface of the medium substrate; three interdigital structures are carved on the first metal patch, a rectangle is etched above the second interdigital structure, and an input feeder line and an output feeder line are etched above the outer side of the first interdigital structure and the outer side of the third interdigital structure respectively and are arranged on the medium substrate. A complementary opening resonator defected ground structure is etched on the second metal patch. A row of metal through holes are correspondingly formed in the bottom edge of the first metal patch, the bottom edge of the medium substrate and the bottom edge of the second metal patch. The broadband band-pass filter low in insertion loss is characterized in that the high-pass characteristic and the low-pass characteristic intersect with each other, is flexible in design and provides a new design concept for filter design. The out-of-band rejection of the low-frequency band of the filter can be controlled, the out-of-band rejection of the high-frequency band of the filter can be improved, and therefore the filter has the advantages of being low in insertion loss, high in selectivity, good in out-of-band rejection and the like.

Description

technical field [0001] The patent of the present invention relates to the field of microwave and millimeter wave filters, in particular to low insertion loss half-mode substrate integrated waveguide filters. Background technique [0002] Filters are the basic components of microwave circuits, and their performance directly affects the performance of the entire system. The planar microstrip line structure filter of the traditional filter is easy to integrate, but it occupies a large area, has a large loss, and has a low Q value. Metal waveguide structure filters have the characteristics of small insertion loss, high selectivity, and high external quality factor, but they are bulky, difficult to process and debug, and difficult to integrate. [0003] The filter based on the semi-mode substrate integrated waveguide technology retains the advantages of high external quality factor and high selectivity of the metal waveguide structure filter, and also has the small size, light w...

AI Technical Summary

Problems solved by technology

Metal waveguide structure filters have the characteristics of small insertion loss, high selectivity, and high external quality factor, but they are bulky, difficult to process and debug, and difficult to integrate

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