Patent ID: 8436691
Filing Date: 2013-05-07
Classification: H01P

Abstract:
1. A signal transmission apparatus comprising: a first circuit layer, a first ground sheet and a second ground sheet, each comprising a rectangular area, and being arranged in the first circuit layer; a second circuit layer, a third ground sheet and a fourth ground sheet, each comprising a rectangular area and being arranged in the second circuit layer; a fifth ground sheet and a sixth ground sheet arranged in a common surface between the first and second circuit layers; and a differential pair comprising a first transmission line arranged between the first circuit layer and the common surface of the fifth and sixth ground sheets, and a second transmission line arranged between the second circuit layer and the common surface of the fifth and sixth ground sheets; wherein the first to sixth ground sheets are parallel to a signal transmission direction of the differential pair, the first to sixth ground sheets have same electric potentials, projections of the rectangular areas of the first and third ground sheets on the fifth ground sheet superpose a first border of the fifth ground sheet, the fifth ground sheet is formed by extending the first border along the signal transmission direction, projections of the rectangular areas of the second and fourth ground sheets superpose a second border of the sixth ground sheet, the sixth ground sheet is formed by extending the second border toward the fifth ground sheet, the differential pair comprises a plurality of section pairs, each of the plurality of section pairs is composed of two sections arranged in the first and second transmission lines symmetrically, each adjacent pair of the plurality of section pairs are equivalent to a capacitor and an inductor; wherein each of the first and second ground sheets further comprises two extended areas that extend along the signal transmission direction from two opposite sides of the corresponding rectangular area, each of the third and fourth ground sheets further comprises two extended areas that extend along an opposite direction of the signal transmission direction from two opposite sides of the corresponding rectangular area.