Toda Kogyo Corporation

Nec Corporation

Tohoku Metal Industries

Seiko Instruments Inc

Sato Rashi Co., Inc.

Yoshiro Sato

Tetsuya Kimura

Jun Koujima

Takanori Doi

Satoshi Ohmae

Tomohiro Dote

Takaaki Ogata

Yasuhiro Aoki

Yoji Okano

Takeshi Uchiyama

Yukio Michishita

Kenichi Yoneyama

Kazumi Yamamoto

Hirochika Sato

Haruo Nakayama

Yoshihisa Hagami

The present invention relates to an RF tag comprising a magnetic antenna for transmitting and receiving information using an electromagnetic induction method, and an IC mounted to the magnetic antenna, wherein the magnetic antenna comprises a magnetic core and a plurality of coils formed on the magnetic core; the coils each have an inductance Lsatisfying the specific relational formula, and are connected in parallel to each other in an electric circuit and disposed in series on the magnetic core; and a combined inductance Lof the magnetic antenna satisfies the specific relational formula. The RF tag of the present invention is used as a magnetic antenna for information communication using a magnetic field component which is capable of satisfying both reduction in size and improvement in communication sensitivity.

Magnetic antenna, and RF tag and board mounted with the RF tag

The present invention relates to a folded dipole antenna comprising a magnetic material comprising a hexagonal Z-type ferrite and/or a hexagonal Y-type ferrite as a main component in which a radiation element and a reflection element each having a folded dipole structure are disposed, and an RF tag comprising the folded dipole antenna and an IC chip connected to the folded dipole antenna. The RF tag according to the present invention has a smaller size than that of the conventional RF tags and is not susceptible to adverse influence from ambient environments, and can be operated at an UHF band or surrounding frequency bands thereof.

Folded dipole antenna and RF tag using the folded dipole antenna

The present invention relates to a magnetic antenna for information communication using a magnetic field component which is capable of satisfying both reduction in size and improvement in communication sensitivity. The magnetic antenna of the present invention is used for transmitting and receiving information using an electromagnetic induction method, and comprises a central core formed of a magnetic material and a non-magnetic material, a coil-shaped electrode material wound around the core, and an insulating layer formed on at least one outside surface of the core on which the coil-shaped electrode material is provided, in which the magnetic material is separated into two or more parts through the non-magnetic material when viewed in a section of the core which is perpendicular to a magnetic flux passing therethrough.

Magnetic antenna, board mounted with the same, and RF tag

The present invention relates to a magnetic antenna for information communication using a magnetic field component which is a magnetic antenna or an RF tag capable of satisfying both reduction in size and improvement in communication sensitivity. More specifically, the present invention relates to an RF tag comprising a magnetic antenna for transmitting and receiving information using an electromagnetic induction method, and an IC mounted to the magnetic antenna, said magnetic antenna comprising a magnetic core and a plurality of coils formed on the magnetic core in which the coils each have an inductance Lsatisfying the specific relational formula, and are formed with bank winding when the coils are lap-wound so as to prevent increase in parasitic capacitance thereof, connected in parallel to each other in an electric circuit, and disposed in series on the magnetic core; and a combined inductance Lof the magnetic antenna satisfies the specific relational formula.

RF tag, magnetic antenna, board mounted with the RF tag, and communication system

The present invention relates to a composite RF tag for transmitting and receiving information using an electromagnetic induction method, comprising a magnetic antenna mounted with an IC, and a resin layer formed around the magnetic antenna, wherein the magnetic antenna comprises a central core formed of a magnetic material and a coil-shaped electrode material disposed around the core. The RF tag according to the present invention comprises the magnetic antenna surrounded by the resin, and therefore can provide a composite magnetic RF tag which can minimize adverse influence by surrounding water or metals in view of maintenance of tools or parts to which the composite RF tag is mounted, and is free from occurrence of any failure or cracking.

Composite RF tag, and tool mounted with the composite RF tag

A composite magnetic antenna for information communication utilizes a magnetic field component as well as a composite RF tag using the composite magnetic antenna, which can be embedded in metals while maintaining a sufficient communication sensitivity unlike conventional RF tags which are unusable in the metal embedding applications. The composite RF tag for transmitting and receiving information using an electromagnetic induction method includes a magnetic antenna on which an IC is mounted, and an insulating material and a metal material or a conductive material which are formed around the magnetic antenna. The magnetic antenna includes a central core formed of a magnetic material, and an electrode material formed into a coil around the central core. The insulating material is formed around the magnetic antenna except for one longitudinal end of the coil of the magnetic antenna. The metal material or the conductive material is formed on an outside of the insulating material.

Composite magnetic antenna and RF tag, and metal part and metal tool on which the composite magnetic antenna or RF tag is installed

A magnetic antenna, suitable for use in an RFID tag and an RFID tag reader/writer, which operates stable even if brought close to a metallic object and suitable for mass-production, and a board mounted with the magnetic antenna. The magnetic antenna has a coil with a magnetic layer and a conductive layer provided on the magnetic layer via an insulating layer or has a plurality of coils each with a magnetic layer having a square or rectangular shape and arranged radially.

Magnetic antenna and board mounted with the same

There is provided a magnetic antenna, suitable for use in an RFID tag and an RFID tag reader/writer, which operates stable even if brought close to a metallic object and suitable for mass-production, and a board mounted with the magnetic antenna. The magnetic antenna has a coil comprising a magnetic layer and a conductive layer provided on the magnetic layer via an insulating layer. Alternatively, the magnetic antenna has a plurality of coils each comprising a magnetic layer having a square or rectangular shape and arranged radially. One ends of the coils are connected in series or parallel to one another by the magnetic layers thereof such that the coils have the same polarity. An insulating layer is provided on one or both outer surface of the coils, and a conductive layer is provided on an outer surface of at least one of the insulating layers. The magnetic antenna is produced using an LTCC technology.

An orthogonal polarization multiplexing transmission apparatus capable of performing dispersion compensation considering a short wavelength side and a long wavelength side of a zero dispersion wavelength. A plurality of light signals of different wavelengths are divided into two orthogonal polarization multiplexing portions, and the light signals of an oddnumber array polarization multiplexing portion and an even-number array polarization multiplexing portion are orthogonal-polarization-multiplexed in each orthogonal polarization multiplexing portions. Adjacent light signals of the two orthogonal polarization multiplexing portions have their mutual planes of polarization rendered non-orthogonal when multiplexed by an optical multiplexer so that, for the purpose of deterring inter-symbol interference, a guard hand having the wavelength spacing rendered wider than that on orthogonal polarization multiplexing is provided in advance.

Orthogonal polarization multiplexing transmission apparatus and multiplexing method used for the same

Wheel nut for automobiles

Optical surge preventing systems and methods for rare earth-doped optical fiber amplifiers are disclosed. The systems are so arranged as to cause any signal existing in a doped fiber section so as not to over excite the rare earth elements in the doped fiber section. In one embodiment, a background signal light with such a wavelength as to cause induced emission in the doped fiber section is always coupled into the doped fiber section regardless of whether a message signal light exists or not. The background signal light may be generated by any suitable light source or a light spontaneously emitted from either end of the doped fiber section. In another embodiment, a dummy signal light is coupled into the doped fiber section if the level of the message signal light becomes less than a predetermined value. Coupling of the background signal light or the dummy signal light into the doped fiber section may be done from either of the message signal input and output sides.

Optical surge preventing method and system for use with or in a rare

A single transmission line bidirectional optical communication system comprising a directional coupler employing a polarizing beam splitter, an optical transmitting circuit for coding the data and converting the coded data into optical signals and outputting said signals, an optical receiving circuit employing a comparator having a function of automatically establishing a threshold for converting optical input signals into electrical signals and then decoding the data, a circuit for detecting the frequency differences between the sending signals and receiving signals, and a line diagnosing circuit. The polarizing beam splitter eliminates a near-end reflected beam, and the optical receiving circuit having a function of automatically establishing a threshold eliminates a remote-end reflected beam. The line diagnosing circuit diagnoses the line condition by comparing the sending frequency and receiving frequency.

Single transmission line bidirectional optical communication system

A noise simulator including a reflection absorbing circuit connected between a high-frequency noise pulse generator based on the principle of a charged delay line and a DC capacitor connected to the power line of the equipment under test. The reflection absorbing circuit is composed of a parallel resistor and a series resistor. The resistances of these resistors are determined so that the impedance at the input side of the reflection absorbing circuit in a condition that a predetermined standard impedance connected thereto is equal to the output impedance of the generator and that the impedance at the output side of the reflection absorbing circuit in the condition that the generator is connected thereto is equal to the predetermined standard impedance. A grounded electric conductor plate is movably disposed commonly adjacent to the series resistor and the DC-cut capacitor to adjust the stray capacitance prior to use for noise simulation.

Growing community of inventors

Tokyo, Japan

Yoshiro Sato