In a transmission line, a first ground conductor pattern and a second ground conductor pattern are connected through a first interlayer connecting conductor, and the first ground conductor pattern and a third ground conductor pattern are connected through a second interlayer connecting conductor. A first signal conductor pattern includes a first bypassing pattern portion that bypasses the first interlayer connecting conductor, and a second signal conductor pattern includes a second bypassing pattern portion that bypasses the second interlayer connecting conductor. Bypassing directions of the first bypassing pattern portion and the second bypassing pattern portion are opposite to each other.

Signal conductor patterns (21, 31) are respectively formed on a first main surface (101) and a second main surface (102) of an insulating substrate (100). Ground conductor patterns (222, 322) are formed on the first main surface (101) and the second main surface (102). A first conductive member (41) is formed in the insulating substrate (100) and electrically connects the signal conductor patterns (21, 31) in the thickness direction. A second conductive member (42) is formed in the insulating substrate (100) and connected to the ground conductor patterns (222, 322). A dielectric member (43) is disposed between the first conductive member (41) and the second conductive member (42), is in contact with the first conductive member (41) and the second conductive member (42), and has a dielectric constant different from the dielectric constant of the insulating substrate (100).

A transmission line. The transmission line includes a reference electrode. The transmission line also includes a stripline. The stripline meanders within a plane. The stripline has a non-planar profile when viewed along a direction parallel to the plane.

A wiring substrate includes a first insulating layer with a first opening, a second insulating layer with a second opening, a high-frequency wiring layer, a first wiring layer, a second wiring layer, and a plurality of conductive pillars. The high-frequency wiring layer including a high-frequency trace is sandwiched between the first insulating layer and the second insulating layer. The first opening and the second opening expose two sides of the high-frequency trace respectively. The high-frequency trace has a smooth surface which is not covered by the first insulating layer and the second insulating layer and has the roughness ranging between 0.1 and 2 μm. The first insulating layer and the second insulating layer are all located between the first wiring layer and the second wiring layer. The conductive pillars are disposed in the second insulating layer and connected to the high-frequency trace.

An electronic device may include one or more radios and one or more antennas. Radio-frequency transmission lines may couple a radio to a corresponding antenna. To more efficiently form a radio-frequency transmission line, the radio-frequency transmission line may be formed from interconnected conductive traces distributed between a plurality of printed circuits. By integrating transmission line structures onto printed circuits that also serve other functions, the device can require less space to implement a radio-frequency transmission line. While one or more of these printed circuits may individually be unsuitable to implement a radio-frequency transmission line with a particular impedance, the composite impedance of these transmission line structures across the printed circuits, when properly configured, may provide a radio-frequency transmission line with the particular impedance.

A high-frequency circuit includes a first electric conductor layer, a first dielectric layer, a circuit layer, a second dielectric layer, a second electric conductor layer arranged in this order, and the circuit layer includes a ground pattern and a transmission line of a high-frequency signal. An electromagnetic wave shield is disposed around the transmission line. The electromagnetic wave shield includes a ground electric conductor on inner surfaces of a plurality of holes extending through the first dielectric layer, the ground pattern, the second dielectric layer, the first electric conductor layer, and the second electric conductor layer. The plurality of holes are a plurality of elongated holes provided at an interval in a direction in which the transmission line is surrounded. In each of the plurality of elongated holes, a longitudinal dimension in the direction in which the transmission line is surrounded is larger than a width dimension.

A transmission line has a first conductor layer extending in a first direction, a second conductor layer disposed on a side of a first surface of the first conductor layer via a first dielectric layer, the second conductor layer extending in the first direction, and a third conductor layer disposed on a side of a second surface of the first conductor layer opposite to the first surface, via a second dielectric layer, the third conductor layer extending in the first direction, wherein a width, in a second direction intersecting the first direction, of each of the second conductor layer and the third conductor layer is different at a plurality of locations in the first direction, and the first conductor layer, the second conductor layer, and the third conductor layer at least partially overlap each other in a plan view from a normal direction of the first surface.

A wiring substrate includes a first insulating layer with a first opening, a second insulating layer with a second opening, a high-frequency wiring layer, a first wiring layer, a second wiring layer, and a plurality of conductive pillars. The high-frequency wiring layer including a high-frequency trace is sandwiched between the first insulating layer and the second insulating layer. The first opening and the second opening expose two sides of the high-frequency trace respectively. The high-frequency trace has a smooth surface which is not covered by the first insulating layer and the second insulating layer and has the roughness ranging between 0.1 and 2 μm. The first insulating layer and the second insulating layer are all located between the first wiring layer and the second wiring layer. The conductive pillars are disposed in the second insulating layer and connected to the high-frequency trace.

A multi-mode transmission line includes a first and second conductive layers, first and second waveguide walls, a strip line, and a blind conductor. The second conductive layer that is formed over the first conductive layer. The first waveguide wall is elongated in a first direction and is in contact with the first conductive layer and the second conductive layer in a vertical direction. The second waveguide wall is elongated in the first direction parallel to the first waveguide wall and is in contact with the first conductive layer and the second conductive layer in the vertical direction. The strip line is formed between the first and second conductive layers and between the first and second waveguide walls. The blind conductor is connected to one of the first conductive layer, the second conductive layer, the first waveguide wall, or the second waveguide wall.

A transmission line device includes first and second transmission lines. The first transmission line includes a first electrode pad that is electrically connected to a first signal conductor pattern, and a second electrode pad and a third electrode pad that are portions of a first ground conductor pattern. The second transmission line includes a fourth electrode pad that is electrically connected to a second signal conductor pattern, and a fifth electrode pad and a sixth electrode pad that are portions of a second ground conductor pattern. The first electrode pad is between the second electrode pad and the third electrode pad, and the fourth electrode pad is between the fifth electrode pad and the sixth electrode pad. The second electrode pad and the third electrode pad are larger than the first electrode pad, and the fifth electrode pad and the sixth electrode pad are larger than the fourth electrode pad.