Patent ID: 7355494
Filing Date: 2008-04-08
Classification: H01P

Abstract:
1. A band-pass filter comprising: a pair of resonators; and another resonator capacitively coupling the pair of resonators, said another resonator having frequency characteristics different from frequency characteristics of the pair of resonators, wherein: the pair of resonators are λa/4 resonators, the another resonator is a λb/2 resonator, wherein λb is set on a higher frequency side than λa and satisfies a relation of λa<λb<λa×3, the pair of λa/4 resonators form a pass band corresponding to a λa wavelength and a pass band corresponding to a λa×3 wavelength, and the λb/2 resonator forms a pass band corresponding to a λb wavelength which complements a pass band between the pass band corresponding to the λa wavelength and the pass band corresponding to the λa×3 wavelength.