The high-frequency transmission line is configured by stacking conductor layers and an insulating layer, and is provided with: a signal via, which extends in a stacking direction and electrically connects the conductor layers together; an input line, which is arranged in one of the conductor layers and inputs an electrical signal to the signal via; a signal line, which is arranged in another one of the conductor layers and is connected to the input line through the signal via; a ground plane, which is arranged in any one of the conductor layers; a conductor arm arranged within a separation region that separates the signal via and the ground plane; and a conductor connection arranged within the separation region and connecting the conductor arm and the ground plane. The conductor arm and the conductor connection are configured to suppress an electrical signal of a predetermined frequency within an electrical signal.

A memory system includes a printed circuit board, at least one memory chip mounted on the printed circuit board, and a memory controller arranged on the printed circuit board and connected to 2.sup.N (where N is an integer of 2 or more) channels, the memory controller configured to perform a write operation and a read operation on the at least one memory chip. In the printed circuit board, a first subset of the channels corresponds to a first channel group configured in a point to point topology, and a remaining subset of the channels corresponds to a second channel group configured in a daisy chain topology.

A memory system includes a printed circuit board, at least one memory chip mounted on the printed circuit board, and a memory controller arranged on the printed circuit board and connected to 2.sup.N (where N is an integer of 2 or more) channels, the memory controller configured to perform a write operation and a read operation on the at least one memory chip. In the printed circuit board, a first subset of the channels corresponds to a first channel group configured in a point to point topology, and a remaining subset of the channels corresponds to a second channel group configured in a daisy chain topology.

An array includes a support structure configured to support columns of beamformer assemblies, and a plurality of beamformer assemblies supported by the support structure. Each beamformer assembly includes at least one beamformer having at least one first beamformer segment and at least one second beamformer segment configured to interconnect with the first beamformer segment.

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 includes an insulator as a base member, a transmission conductor, and a ground layer. A connector is provided at a wiring substrate to fix the transmission line. The transmission line includes a signal columnar conductor having a solid columnar shape integrated with the transmission conductor, and ground columnar conductors having solid columnar shapes integrated with the ground layer. The connector has a through hole corresponding to the signal columnar conductor, and through holes corresponding to the ground columnar conductors. Conductive films are respectively provided on the inner peripheral surfaces of the through holes. The signal columnar conductor is inserted into the through hole, and the ground columnar conductors are respectively inserted into the through holes.

A radio frequency transmission arrangement comprises a ground plate having an aperture comprising a slot with an elongate cross-section and substantially parallel sides, and a first and second transmission line. The thickness of the ground plate is greater than a width of the slot. The aperture is partially filled with a solid dielectric material and partially filled with air. The first transmission line comprises a first elongate conductor on a first side of the ground plate and has an end terminated with a first termination stub. The second transmission line comprises a second elongate conductor on the opposite side of the ground plate and has an end terminated with a second termination stub. The first transmission line is arranged to cross the slot at a point adjacent to the first termination stub, and the second transmission line is arranged to cross the slot at a point adjacent to the second termination stub.

A memory system includes a printed circuit board, at least one memory chip mounted on the printed circuit board, and a memory controller arranged on the printed circuit board and connected to 2.sup.N (where N is an integer of 2 or more) channels, the memory controller configured to perform a write operation and a read operation on the at least one memory chip. In the printed circuit board, a first subset of the channels corresponds to a first channel group configured in a point to point topology, and a remaining subset of the channels corresponds to a second channel group configured in a daisy chain topology.

A memory system includes a printed circuit board, at least one memory chip mounted on the printed circuit board, and a memory controller arranged on the printed circuit board and connected to 2.sup.N (where N is an integer of 2 or more) channels, the memory controller configured to perform a write operation and a read operation on the at least one memory chip. In the printed circuit board, a first subset of the channels corresponds to a first channel group configured in a point to point topology, and a remaining subset of the channels corresponds to a second channel group configured in a daisy chain topology.

Radio frequency transmission lines in a multi-layer printed circuit board structure include first and second rows of ground vias that extend vertically through the printed circuit board structure. A first transmission line segment extends horizontally along a first portion of the multi-layer printed circuit board structure and a second transmission line segment extends horizontally along a second portion of the multi-layer printed circuit board structure, the second transmission line segment vertically spaced apart from the first transmission line segment. A vertical dielectric structure extends between the first and second transmission line segments and a blind ground via extends vertically through the printed circuit board structure adjacent the vertical dielectric structure.