Fujikura Limited

National Institute for Materials Science

International Business Machines Corporation

Agency for Science, Technology and Research

Independent Administrative Institution National Institute for Materials Science

Ken Sakuma

Naoto Hirosaki

Ning Guan

Kensuke Ogawa

Naoki Kimura

Hideyuki Hosoya

Koji Omichi

Hajime Yamamoto

Kazuhiro Goi

Guo-Qiang Patrick Lo

Mingbin Yu

Kyota Ueda

Hirokuni Ogawa

Yong Tsong Tan

Hwee Gee Teo

Daigo Fujita

Shimon Ishikawa

Bodhisatwa Sadhu

Akira Wada

Arun Paidimarri

Masakazu Ohashi

Ryuji Suzuki

Daiichiro Tanaka

Kiyoshi Kobayashi

Koichiro Masuko

Mark Yeck

Hiroyuki Tanabe

Tomoko Shikata

Takeshi Fukuda

Tomoko Fujii

Toshisada Sekiguchi

A phased array antenna module includes an analog circuit portion that adjusts at least one of an intensity and a phase of a signal transmitted or received by each of a plurality of antenna elements, a digital control portion that controls the analog circuit portion, a strobe mechanism portion that is provided between the analog circuit portion and the digital control portion, latches a control signal output from the digital control portion when a strobe latch signal is input, and outputs the control signal to the analog circuit portion, a state determination portion that determines whether or not the control signal is in a fixed state, and a timing adjustment portion that outputs the strobe latch signal to the strobe mechanism portion when a ready signal is output from the state determination portion.

Phased array antenna module

A phased array antenna () includes: a plurality of antenna elements (to); a plurality of signal paths (Rand R) that are connected to each of the antenna elements; a storage unit (M) configured to store a set values of at least one of amplitudes or phases of a signal passed through at least one predefined reference path among the plurality of signal paths with regard to at least one of the antenna elements, and an amplitude and phase control unit (or) configured to control at least one of the amplitude or the phase of the signal passed through the reference path connected to the antenna element by using the set value stored in the storage unit, and configured to control amplitude or phase of signal passed through the signal path other than the reference path.

Phased array antenna

A wireless communication device includes a beamforming antenna and a beam former that sets a beam pattern of the beamforming antenna depending on an antenna weight vector selected from a beam table. In the beam table, a peak direction of the array factor corresponding to each antenna weight vector is non-uniformly distributed in an angular space.

Wireless communication device

A wireless communication device includes, a beamforming antenna, a storage that stores a plurality of optimized beam tables in which a peak direction of an array factor corresponding to each antenna weight vector are non-uniformly distributed in an angular space, the respective plurality of optimized beam tables is optimized in different directions, and a beamformer that sets a beam pattern of the beamforming antenna based on an antenna weight vector constituting one optimized beam table selected from the plurality of optimized beam tables.

A wireless communication system includes a first wireless communication device and a server communicably connected to the first wireless communication device. The server accumulates a plurality of optimized beam table, and selects therefrom an optimized beam table to be used by the first wireless communication device, and, the first wireless communication device obtains the optimized beam table selected by the server by communicating with the server, and performs a wireless communication using the obtained optimized beam table.

Wireless communication system

A wireless communication device includes a storage that stores a standard beam table, which is a table constituted by a plurality of antenna weight vector sets corresponding to beam patterns in which beam angular intervals are uniform, and a controller that determines a direction, in which a communication partner's wireless communication device exists, as a direction to be optimized, generates an optimized beam table by changing the angular intervals between the beams of the standard beam table with respect to the direction to be optimized so as to be dense, and performs a communication with the communication partner's wireless communication device using the optimized beam table.

Wireless communication device and wireless communication method

A wireless communication device includes a look-up table that stores a beam pattern table, and at least one beamforming antenna transmitting or receiving a radio signal with a beam pattern specified by a set of antenna weight vectors selected from the beam pattern table, where a number of antenna weight vectors for obtaining a beam pattern with a narrow half power beam width for transmission included in the beam pattern table is larger than a number of antenna weight vectors for obtaining a beam pattern with a narrow half power beam width for reception.

There is provided a planar optical waveguide element in which an optical waveguide core comprises an inner side core having protruding portions that form a rib structure, and an outer side core that is provided on top of the inner side core and that covers circumferential surfaces of the protruding portions, wherein a refractive index of the outer side core is lower than an average refractive index of the inner side core. The structure of the planar optical waveguide element can be applied even when the core is formed from a material having a higher refractive index than that of a silica glass-based material such as silicon (Si) or silicon nitride (SiN).

Planar optical waveguide element, chromatic dispersion compensator, optical filter, optical resonator and methods for designing the element, chromatic dispersion compensator, optical filter and optical resonator

There is provided a planar optical waveguide element including a core, the core including first and second portions and a gap portion that is positioned in a center of a width direction of the core between the first and second portions so as to extend in a light waveguide direction. The gap portion has a lower refractive index than that of the first and second portions, and a single mode propagated in the waveguide element has a span crossing the first and second portions.

An incandescent lamp color light emitting diode lamp comprises a semiconductor blue light emitting diode chip having a center emission wavelength in a range of from 400 nm to 480 nm and a phosphor that absorbs light emitted from the diode chip to emit light having a different wavelength than the light emitted from the diode chip. The phosphor is represented by a general formula of M(Si, Al)(O, N):Eu. The main phase is an &#x3b1;-SiAlON phosphor having an &#x3b1; SiAlON structure, wherein M is at least one element of Ca, Y, Mg, Li, Sc, Pr, Nd, Pm, Sm, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, and Sr and p is from 0.75 to 1.0; and q is between 0.02 and 0.09. The diode lamp emits light having an emission color produced by a mixture of the light emitted from the semiconductor blue light emitting and the light emitted from the &#x3b1;-SiAlON. The chromaticity range thereof falls within the range defined by chromaticity coordinates (x, y) of (0.4775, 0.4283), (0.4594, 0.3971), (0.4348, 0.4185), and (0.4214, 0.3887) on the XYZ chromaticity diagram.

Phosphor and an incandescent lamp color light emitting diode lamp using the same

A method for manufacturing a planar optical waveguide device of which a core includes a plurality of alternatively arranged fin portions and valley portions to form a grating structure, in which the core widths of the valley portions vary along the longitudinal direction, the method including: a high refractive index material layer forming step of forming a high refractive index material layer; a photoresist layer forming step of forming a photoresist layer on the high refractive index material layer; a first exposure step of forming shaded portions on the photoresist layer using a phase-shifting photomask; a second exposure step of forming shaded portions on the photoresist layer using a binary photomask; a development step of developing the photoresist layer; and an etching step of etching the high refractive index material layer using the photoresist pattern resulted from the development step.

Manufacturing method of planar optical waveguide device with grating structure

There is provided an optical waveguide element comprises: a core of an optical waveguide; and a Bragg grating pattern that is provided on the core, wherein a pitch of the Bragg grating pattern takes a value from among three or more predetermined discrete values; the pitches that take the respective discrete values are present in a plurality of locations over an entire length of the optical waveguide respectively; and if a value from among all of the discrete values which has the highest distribution frequency is taken as M, and if the closest value to the M which is larger than the M is taken as A, and if the closest value to the M which is smaller than the M is taken as B, then a difference expressed as A&#x2212;M is equal to a difference expressed as M&#x2212;B.

Optical waveguide element, chromatic dispersion compensator, methods for designing chromatic dispersion compensator, optical filter, methods for designing optical filter, optical resonator and methods for designing optical resonator

There is provided a planar optical waveguide element comprises a core of an optical waveguide; and first Bragg grating pattern and second Bragg grating pattern that are provided on the core, wherein the first Bragg grating pattern and the second Bragg grating pattern are mutually parallel along a propagation direction of guided light.

Planar optical waveguide element, chromatic dispersion compensator, methods for designing chromatic dispersion compensator, optical filter, methods for designing optical filter, optical resonator and methods for designing optical resonator

A method for manufacturing a planar optical waveguide device including a core of which a top face is provided with a groove section filled with a groove section filler made of a low refractive index material having a refractive index lower than that of the core, the method including; a first high refractive index material layer forming step of forming a high refractive index material layer; a low refractive index material layer forming step of forming a low refractive index material layer made of the low refractive index material on the high refractive index material layer; a groove section filler forming step of forming the groove section filler by trimming both lateral portions of the low refractive index material layer; and a second high refractive index material layer forming step of forming a high refractive index material layer so as to fill the both sides of the lateral portions of the groove section filler.

A bullet type light emitting diode lamp or a chip-type light emitting diode lamp includes a semiconductor light emitting element, and a plurality of fluorescent materials that absorb part or whole of light emitted from the semiconductor light emitting element, and emit fluorescence at a wavelength different from that of the absorbed light. The fluorescent materials include a phosphor of a CaAlSiNcrystalline phase.

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Sakura, Japan

Ken Sakuma