Bandpass filter, and wireless communication module and wireless communication device using the bandpass filter

摘要

[Object] An object is to provide a bandpass filter that can be used for a wide frequency band and has a large degree of freedom in designing a passband, and a wireless communication module and a wireless communication device that use the bandpass filter.;[Solution] A bandpass filter includes first to third resonance electrodes 31a, 31b, and 31c sequentially arranged side-by-side such that they are electromagnetically coupled to each other, the first to third resonance electrodes 31a, 31b, and 31c being grounded at one end and constituting first to third resonators, respectively; a first input/output coupling electrode 40a facing the first resonance electrode 31a and electromagnetically coupled thereto; a second input/output coupling electrode 40b facing the second resonance electrode 31b and electromagnetically coupled thereto; and a resonator coupling electrode 43 configured to provide electromagnetic coupling between the first resonance electrode 31a and the third resonance electrode 31c. The first and second resonators have the same resonance frequency which is different from a resonance frequency of the third resonator. The first to third resonators are used to produce a passband. The bandpass filter can be used for a wide frequency band and has a large degree of freedom in designing the passband.