Patent ID: 7196597
Filing Date: 2007-03-27
Classification: H01P

Abstract:
1. A bandpass filter for a differential signal, comprising a dielectric body, a first line and a second line on a surface of the dielectric body or a first surface of an inner part of the dielectric body arranged symmetrically to each other with respect to a surface of symmetry crossing the first surface, and a third line and a fourth line on another surface of the dielectric body or a second surface which is another surface of an inner part of the dielectric body and faces the first surface, arranged symmetrically to each other with respect to the surface of symmetry, the first to fourth lines having respective line lengths equivalent to a quarter wavelength of a center frequency of a used band; one end of each of the first to fourth lines being an input/output end with the other ends being an open end; and input/output ends of the first line and second line being arranged close to the open ends of the third line and the fourth line.