National Institute of Information and Communications Technology, Incorporated

Communications Research Laboratory, Inc.

Other

Tokyo University of Agriculture and Technology

National Institute of Information and Communications Technology, Incorporated Administrative Agency

Communications Research Laboratory, Independent Administrative Institution

Communications Research Laboratory, Independant Administration Institution

Sharp Kabushiki Kaisha Corporation

Matsui, Toshiaki

Toshiaki Matsui

Hitoshi Utagawa

Hiroshi Ohta

Yoshiyuki Suda

Akira Motohashi

Kyohei Degura

Katsumi Okubo

Takuma Yagi

Akifumi Kasamatsu

Nobumitsu Hirose

Takahiro Tsukamoto

Atsushi Yamada

Akira Kawakami

Akira Kobayashi

Munecazu Tacano

Saburo Yokokura

Harunobu Yuzawa

Masahiro Kiyokawa

A semiconductor laminate film includes a silicon substrate and a semiconductor layer formed on the silicon substrate and containing silicon and germanium. The semiconductor layer having a surface roughness Rms of 1 nm or less. Further, the semiconductor layer satisfies the following relationship t≤0.881×xwhere t represents a thickness (nm) of the semiconductor layer, and x represents a ratio of the number of germanium atoms to a sum of the number of silicon atoms and the number of germanium atoms in the semiconductor layer. Also, the semiconductor layer being a mixed crystal semiconductor layer containing silicon and germanium.

Manufacturing method for semiconductor laminated film, and semiconductor laminated film

A method of producing a semiconductor laminate film includes forming a semiconductor layer containing silicon and germanium on a silicon substrate by a sputtering method. In the sputtering method, a film formation temperature of the semiconductor layer is less than 500&#xb0; C., and a film formation pressure of the semiconductor layer ranges from 1 mTorr to 11 mTorr, or, a film formation temperature of the semiconductor layer is less than 600&#xb0; C., and a film formation pressure of the semiconductor layer is equal to or more than 2 mTorr and less than 5 mTorr. The sputtering method uses a sputtering gas having a volume ratio of a hydrogen gas of less than 0.1%, and the semiconductor layer satisfies a relationship of t&#x2264;0.881&#xd7;x, where t represents a thickness (nm) of the semiconductor layer, and x represents a ratio of the number of germanium atoms to a sum of the number of silicon atoms and the number of germanium atoms in the semiconductor layer.

A radiation type oscillator including a radiation type oscillator substrate including a microwave transistor for generating negative resistance by short-duration operation and a resonant cavity structure; a high-frequency pulse signal of an oscillation frequency/frequency bandwidth determined by negative resistance produced by the short-duration operation of the microwave transistor and the resonant cavity structure is generated as a transmitted RF signal and simultaneously radiated into space. The radiation type oscillator performs oscillating operation when a received RF signal that is a reflected wave of the transmitted RF signal from an object of detection enters the radiation type oscillator, an IF signal is acquired from an IF signal output terminal owing to homodyne mixing by the radiation type oscillator itself, and this is analyzed and processed to detect the object of detection.

Pulse radar device

To provide a microwave/milliwave band high-frequency pulse signal generating device that enables realization of structural simplification, high performance, compact integration, easy design, low power consumption, and low cost. A radiation type oscillator substrate Shaving an inner-layer GNDinterposed between a front-side dielectric substrateand a rear-side dielectric substrateis provided on the radiation surface side with a pair of axially symmetrical patches, a gate electrodeand drain electrodeof a microwave transistorare respectively connected to the conductor patches, DC bias is supplied to the gate electrodethrough an RF choke circuit, a monopulse from a monopulse generation circuitis supplied to the drain electrodethrough an RF choke circuit, an impedance linesatisfying an oscillating condition is connected to a source electrode, and a high-frequency pulse signal of an oscillation frequency/frequency bandwidth determined by negative resistance produced by short-duration operation of the microwave transistorand the resonant cavity structure is generated and simultaneously radiated into space.

Pulse signal generation device

To provide a microwave/milliwave UWB pulse wireless communication device that enables realization of structural simplification, high performance, compact integration, easy design, low power consumption, and low cost. A radiation type oscillator is configured by a radiation type oscillator substrate Sequipped with a microwave transistorfor generating negative resistance by short-duration operation and a resonant cavity structure, a high-frequency pulse signal of an oscillation frequency/frequency bandwidth determined based on negative resistance produced by the short-duration operation of the microwave transistorand the resonant cavity structure is generated as a transmitted RF signal and simultaneously radiated into space, and the radiation type oscillator is caused to perform oscillating operation when a received RF signal arriving from an external wireless communication device enters the radiation type oscillator, whereby a received data signal is established based on acquisition of an IF signal owing to mixing by the radiation type oscillator itself.

Pulse wireless communication device

This inventive wireless communication system comprises a plurality of wireless communication devices () each including a radiating oscillator (), a baseband signal generating unit () and a reception signal detecting unit (). In this wireless communication network system, the wireless communication devices are arranged to face each other at a location where a pull-in phenomenon is caused, a signal transmitted from one of the wireless communication devices is an oscillation signal of the radiating oscillator () of the one of the wireless communication devices, the frequency of the oscillation signal varies with the baseband signal, the variation in the frequency is transmitted to the other ones of the facing wireless communication devices () by the pull-in phenomenon, the oscillation frequencies of the radiating oscillators () of the other ones of the facing wireless communication devices () also vary, and the other ones of the facing wireless communication devices () extract the variation by receiving the variation in the frequency through the reception signal detecting units (). As a result, the present invention can provide a less expensive wireless network system which comprises wireless communication devices having respectively a very simple structure, consumes less electric power and can secure high-quality signal transmission.

Wireless communication network system

A baseband signal processing unit changes the collector current of a transistor () formed by a bias control circuit () in accordance with a baseband transmission signal input from a baseband signal input terminal (), changing the drain bias of a high-frequency transistor () to realize frequency modulation by changing the oscillation frequency, and the radiation wave thereof forms a transmit RF signal, whereby the transmission operation is performed. On the other hand, the oscillation signal is synchronized with a frequency modulated RF signal that arrives from outside, the change in frequency caused by the frequency modulation is generated as a change in the drain bias of the high-frequency transistor (), and reception operation is performed by taking out that change as a voltage amplitude change from the baseband signal output terminal (). As a result, it is possible to provide a microwave/millimeter wave communication apparatus that is simple in structure, low cost, and low power consumption.

Microwave/millimeter wave communication apparatus

A microwave/millimeter wave sensor apparatus including a planar radiation type oscillator substrate having an inner-layer GND interposed between a front surface side dielectric substrate and a rear surface side dielectric substrate and a pair of conductor patches in an axis-symmetric manner on the side of the front surface layer. A gate and drain of a microwave transistor are respectively connected to the conductor patches to supply power to the gate and the drain of the microwave transistor through a gate-side RF choke circuit and a drain-side RF choke circuit. An impedance line satisfying an oscillation condition is connected to a source and a transmit RF signal in an RF zone as a planar radiation type oscillator is transmitted and a receive RF signal as reflected waves is received from a measured object, thus obtaining an IF signal as the sensing information through homodyne mixing.

Microwave/millimeter wave sensor apparatus

A wireless communication device having extremely simple constitution is used, and a low-cost and low power consumption wireless network system with high-quality signals is provided. The wireless network system comprises a plurality of wireless communication devices () each comprising a radiating oscillator () configured to integrate a transistor into a microwave oscillating resonator to generate a negative resistance and to commonly use a function of an antenna (), an intermediate frequency signal generating section () and a receiving signal detecting section (). In the wireless network system, the wireless communication devices are arranged to face at a position, at least one of the wireless communication devices has an intermediate frequency signal generating section having a frequency band signal generating function different from that of others, the receiving signal detection section having a function that can discriminate and receive a frequency band different from that of others, a signal transmitted from the one wireless communication device is transmitted to the other facing wireless communication device, and the other facing wireless communication device receives and extracts the signal by the receiving signal detecting section.

Wireless network system

It is possible to improve the negative resistance characteristic that can be expected when an SNS (superconductor-normal conductor-superconductor) structure is used as a structure unit for series connection. On the top of a first superconducting electrode, a second superconducting electrode is superimposed so as to sandwich an insulation film between the first and second superconducting electrodes, with parts of cross sections of the second superconducting electrode and insulation film placed on the top. A normal superconducting line electrically connects the first and second superconducting electrodes passing along the cross section of the insulation film, thereby constituting a structure unit having a single weak link. A plurality of such structure units connected in series are prepared. At the both ends of the series the first or second superconducting electrode is an element connected to a leading line. The structure units are arranged so that the cross sections of the insulation films along which the normal conducting line passes are arranged in the sale direction.

Electromagnetic wave detection element and electromagnetic wave detection device using the same

A magneto-encephalographic equipment superconducting magnetic-shield comprising a vacuum-tight body comprising an outer enclosure wall, a first inner enclosure wall inserted in the outer enclosure wall to define a upper closed space, and a second inner enclosure wall to define a lower open space. The first and second inner enclosure walls are arranged with the bottom of the first inner enclosure wall facing the ceiling of the second inner enclosure wall. A first enclosure of HTSC and a second enclosure of high-permeability material are concentrically arranged in the annular vacuum space defined between the first and second inner enclosure walls and the outer enclosure wall. A head-accommodating area is delimited by the hollow partition between, the bottom of the first inner enclosure wall and the ceiling of the second inner enclosure wall both facing each other, and a plurality of SQUID sensors are arranged in the upper closed space, encircling the head-accommodating area.

Measuring structure for magneto encephalographic equipment with a superconducting magnetic-shield

The present invention provides a low-noise MEG apparatus of high sensitivity. A MEG apparatus using a magnetic shield of high critical temperature superconductor is set on the floor of a building via mechanical vibration suppressor supports to prevent appearance of noise signals. Also, the apparatus is equipped with means for preventing any relative displacement between the SQUID magnetic sensors and the magnetic shield of high critical temperature superconductor, thereby not letting an inevitable mechanical vibration of least strength produce any variable components of the trapped static magnetic field, which the SQUID magnetic sensors could be sensitive to.

Apparatus for measuring the neuro-magnetic field from a human brain and method for operating the same

Roadside wireless devices are installed at roadside positions corresponding to the traffic lanes entering an intersection. Roadside wireless devices are also installed at roadside positions corresponding to the traffic lanes exiting an intersection. The roadside wireless devices on the entrance side receive an identification number from vehicle-mounted wireless ID devices of vehicles entering the intersection and transmit them to a roadside traffic monitoring device. Thereafter, the roadside wireless devices on the exit side receive an identification number from the vehicle-mounted wireless ID devices of vehicles exiting the intersection and transmit them to the roadside traffic monitoring device. From the identification numbers received, the roadside traffic monitoring device is able to determine the entrance from which a vehicle judged to be the same one had entered and the exit from which it exited, along with the type of vehicle. Short-term and long-term statistical data on the flow of vehicles and the situation of road usage can be acquired efficiently.

Road traffic monitoring system

A combination antenna and radio communication device comprises a dielectric base ( ) on which a multislot antenna ( ) made of conductor, a coplanar transmission line ( ), a power supply line, and a high-frequency unit ( ) are provided. A conductive package ( ) and the dielectric base ( ) hermetically seal the high-frequency unit ( ), the coplanar transmission line ( ), and the multislot antenna ( ). The lower face of the dielectric base ( ) faces to a conductive sheet ( ) having an opening ( ) for passing therethrough electromagnetic waves. Electromagnetic waves are passed through the dielectric base ( ) and taken out through the opening ( ). Therefore the combination antenna and radio device for pseudo-millimeteric and millimeteric waves have a small size, high performance and excellent massproductivity.

Radio communication device

A method for measuring harmonic load-pull including supplying a fundamental frequency signal to a frequency multiplication device under test and obtaining a target even-order multiplied frequency signal. The fundamental load impedance and an even-harmonic load impedance are independently controlled with a load mechanical tuner having an open-ended stub that is one-quarter wavelength long at the fundamental frequency and satisfies a short-circuit condition with respect to the fundamental signal. A fundamental source impedance and an even-harmonic source impedance of an input signal applied to the device under test are independently controlled with a source mechanical tuner having a short-circuit stub that is one-quarter wavelength long at the fundamental frequency and satisfies a short-circuit condition with respect to even-harmonics.

Growing community of inventors

Koganei, Japan

Toshiaki Matsui