Hitachi Metals, Ltd.

Hitachi Cable, Inc.

Hitachi, Ltd.

Nobuaki Kitano

Naoki Iso

Tomoyuki Ogawa

Yoshiaki Ishigami

Masahisa Kaneta

Tsukasa Fujishima

Masahiro Arai

Ken Takei

Taichiroo Konno

Kazuyuki Iizuka

Seiichi Kashimura

Haruyasu Komano

Hiroyuki Hori

Satoshi Yoshihara

Seiji Kado

Yukio Abe

Kazuo Tamura

Toshiyuki Ando

Yasuo Ishikawa

Koutarou Tanaka

Katsuya Ohtomo

A phase-shifting circuitincludes a signal conductorthat transmits signals, and a dielectric bodythat is disposed to overlap the signal conductor, said phase-shifting circuit changing the phase of the signals by changing the area of an overlapping sectionwhere the signal conductorand the dielectric bodyoverlap each other. The phase-shifting circuit further includes a transformer unitfor matching impedance between the overlapping sectionand non-overlapping sectionwhere the signal conductorand the dielectric bodydo not overlap each other, said transformer unit being provided at end sections of the dielectric body, said end sections being on the input side and output side of the signals. The transformer unitincludes a high-impedance sectionthat is provided on the overlapping sectionside, and a low-impedance section, which is provided on the non-overlapping sectionside of the high-impedance section, and which has a lower characteristic impedance than the high-impedance section

Phase-shifting circuit and antenna device

An antenna device includes a transmission line for propagating high frequency signal, and a plurality of antenna elements connected to the transmission line. The transmission line includes a first plate-shaped conductor, a second plate-shaped conductor, and a third plate-shaped conductor electrically grounded, a first central conductor disposed between the first and second plate-shaped conductors, a second central conductor disposed between the second and third plate-shaped conductors, an electrically connecting member inserted in an inserting hole formed through the second plate-shaped conductor, to electrically connect the first and second central conductors together, and an electrically grounded conductor disposed adjacent to the electrically connecting member. At least one of the first and second central conductors is provided with a through hole formed adjacent to the electrically connecting member, thereby electrically connects together wiring patterns provided on both surfaces, respectively, of a dielectric substrate of the at least one of the first and second central conductors.

Antenna device

An antenna device includes a center substrate including a dielectric substrate and a center conductor on the dielectric substrate, and two ground plates sandwiching via an air layer the center substrate therebetween to form a feeder line. A hole is formed in the dielectric substrate on at least one side of the center conductor along a longitudinal direction of the center conductor.

An antenna device includes an input/output portion for a high frequency signal to be input or output, a distributing portion for distributing the high frequency signal input to the input/output portion into a plurality of high frequency signals, a phase shifting portion for imparting the plurality of high frequency signals with a predetermined amount of phase shift, and a feeding portion for feeding a plurality of antenna elements with the plurality of high frequency signals imparted with the predetermined amount of phase shift to cause the plurality of antenna elements to radiate the plurality of high frequency signals. The feeding portion is configured as a triplate line with a center conductor placed between one pair of parallel plate shaped outer conductors.

Antenna device including a phase shifter and a feeding portion configured as a triplate line with a center conductor

A phase shifter includes dielectric members including facing portions facing a signal line formed on a surface of a substrate and being made of a dielectric material, a supporting member configured to support the dielectric members and receive a moving force for moving the dielectric members in a direction which is parallel to the substrate and crosses the signal line, and a moving mechanism configured to apply the moving force to the supporting member. At least either the dielectric members or the supporting member is provided with a protrusion configured to keep a distance between the facing portions of the dielectric members and the signal line.

Phase shifter having dielectric members inserted into a movable support frame

An antenna device includes a first triplate line and one or more second triplate lines that are connected to the first triplate line so as to cross the first triplate line. Two ground plates of each second triplate line include respective flange portions that are in contact with and fixed to a surface of one of two ground plates of the first triplate line. At least one of a surface of each flange portion that contacts the one of the ground plates of the first triplate line and the surface of the one of the ground plates of the first triplate line that contacts each flange portion is provided with an irregular portion for reducing a contact area between each flange portion and the one of the ground plates.

A phase-shift circuit being smaller in size than a conventional phase-shift circuit and being capable of causing a phase difference equivalent to or larger than that in the conventional phase-shift circuit between an input signal and an output signal is achieved. A phase-shift circuit includes: a signal line; and a dielectric member overlapping the signal line and being capable of reciprocating in a direction intersecting the signal line, and changes a phase of a signal propagating through the signal line. The dielectric member is configured of a frame body and a dielectric plate provided inside the frame body and having an overlapping area with the signal line increased or decreased by the reciprocation, and the frame body has a permittivity lower than a permittivity of the dielectric plate.

Phase-shift circuit and antenna device

An antenna device includes a plurality of phase shift circuits to which distributed signals are respectively input and a plurality of antenna elements to which signals output from the respective phase shift circuits are input. At least one of the plurality of phase shift circuits has a signal line in which a first region in which paired dielectric members are disposed, a second region in which no paired dielectric members is disposed and a third region in which paired dielectric members are disposed are provided in this order along a propagation direction of a signal. Moreover, a characteristic impedance of the first region in a state where the paired dielectric members are not disposed and a characteristic impedance of the third region in a state where the paired dielectric members are not disposed are higher than a characteristic impedance of the second region.

Phase shift/antenna circuit having a signal line with first and third regions for engaging dielectric members and a second region that does not engage the dielectric members

A transmission line has a triplate line including a first outer conductor and a second outer conductor disposed in parallel with each other at a predetermined interval, and a central conductor disposed in a space between the first outer conductor and the second outer conductor; and a dielectric spacer interposed between the first and second outer conductors and the central conductor and configured to support the central conductor. The central conductor has a supported portion supported by the dielectric spacer, and first and second high-impedance portions having characteristic impedances higher than a characteristic impedance in the supported portion. The first and second high-impedance portions are disposed on input and output sides, respectively, of the supported portion.

Transmission line and antenna device

An antenna device has a feed line including a triplate line. Each triplate line has a central conductor and two ground plates sandwiching the central conductor via an air layer. At least a part of the triplate line is configured such that the two ground plates sandwich a center substrate including a wiring pattern as the central conductor provided on a dielectric substrate via the air layer.

Antenna device including triplate line including central conductor and ground plates

An antenna device () includes a plurality of triplate lines () each of which includes a central conductor (A) arranged between one pair of outer conductors (A,A) parallel to each other, and a plurality of antenna elements () to transmit high frequency signals distributed by the plurality of triplate lines (). The plurality of triplate lines () include a first triplate line () and a second triplate line () arranged non-parallel to each other and at a predetermined angle therebetween so that respective central conductors (A) of the first triplate line () and the second triplate line () are intersected and connected together.

An electromagnetic wave radiation coaxial cable and a communication system using the same. The electromagnetic wave radiation coaxial cable includes an inner conductor which is formed of a conductor and extends along a cable axis, an insulator covering the inner conductor, and an outer conductor spirally wound around the insulator in a single winding at a predetermined pitch to provide a gap from which a part of the insulator is exposed. Following formula is established: when &#x3bb; is a wavelength of a radio frequency signal to be transmitted or received, &#x2208;is a relative dielectric constant of the insulator at the wavelength &#x3bb;, and P is a winding pitch of the outer conductor along the direction of the cable axis.

Electromagnetic wave radiation coaxial cable and communication system using the same

The present invention provides a high/low frequency dual wireless location detection and information transmission system which is high in reliability and maintainability, and can be easily installed. A leakage coaxial inner conductor and a conductor line provided in parallel are short-circuited at an end, a single leakage coaxial operation and a loop operation of the inner conductor and the conductor line are performed at the same time, the ID of a tag is communicated using magnetic fields which locally exist near the conductor line by the loop, and wireless position detection and information communications which are less affected by the influence of ambient environments due to electromagnetic waves in a closed area are realized by open-type lines.

Low/high frequency shared leakage antenna, base station apparatus and close-range detection system using the antenna

A light-emitting element includes a semiconductor substrate, a light emitting portion including an active layer sandwiched between a first cladding layer of a first conductivity type and a second cladding layer of a second conductivity type different from the first conductivity type, a reflective portion provided between the semiconductor substrate and the light emitting portion for reflecting light emitted from the active layer, and a current spreading layer provided on the light emitting portion opposite to the reflective portion and including a concavo-convex portion on a surface thereof. The reflective portion includes a plurality of pair layers each including a first semiconductor layer and a second semiconductor layer different from the first semiconductor layer, and the first semiconductor layer has a thickness Tdefined by formulas (1) and (3), and the second semiconductor layer has a thickness Tdefined by formulas (2) and (4).

Light-emitting element and method of making the same

A semiconductor light-emitting device includes a support structure, and a light-emitting structure. The support structure includes a support substrate, and a support substrate side bonding layer disposed on one surface of the support substrate. The light-emitting structure includes a light-emitting structure side bonding layer bonded to the support substrate side bonding layer, a reflection region disposed on the support substrate side bonding layer opposite the support substrate, and a semiconductor multilayer structure including a light-emitting layer disposed on the reflection region opposite the light-emitting structure side bonding layer for emitting a light with a predetermined wavelength, and a light-extraction surface disposed on the light-emitting layer opposite the reflection region for reflecting diffusely the light. The reflection region includes a transparent layer of a material with a lower refractive index than that of the semiconductor multilayer structure, and a reflection layer of a metallic material. The transparent layer has such a thickness that interference caused by multiple reflection of light inputted to the transparent layer can be suppressed.

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Hitachi, Japan

Nobuaki Kitano