A filter includes: an input terminal configured to receive a radio frequency signal, and an output terminal of the filter configured to output the radio frequency signal obtained after filtering. The filter further includes a first filter capacitor and a first ground via. The first filter capacitor is disposed in a substrate or on a surface of a substrate. A first terminal of the first filter capacitor is coupled to the input terminal or the output terminal of the filter, a second terminal of the first filter capacitor is coupled to a terminal of the first ground via disposed in the substrate, and another terminal of the first ground via is coupled to a ground.