Electromagnetic coupling interdigital bandpass filter based on multiple through holes and design method

The invention discloses an electromagnetic coupling interdigital bandpass filter based on multiple through holes and a design method. Through forming staggered through holes in a substrate, the filtering effect is generated, so a produced product can not only make a planar interdigital filter into a three-dimensional interdigital filter, but also make the filter being in the substrate instead of being on the substrate, in a microwave integrated circuit, the filter can realize filtering in the substrate, a filter's space occupation rate is minimized, and a problem that the planar interdigital filter has a large duty cycle in the microwave integrated circuit is overcome. The product produced through the method has advantages of small size, wide bandwidth and good filtering effect. The invention further provides a specific design method, the quantity of the metal through holes, adjacent metal gaps, the metal through hole radius and thickness of a dielectric substrate can be calculated, and rapid and accurate man