Patents by Inventor Kenji Tahara
Kenji Tahara has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).
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Patent number: 12273080Abstract: The present disclosure facilitates impedance matching between a power amplifier and filters. A radio-frequency circuit includes a power amplifier, a plurality of transmit filters, a switch, a plurality of first matching networks, and a second matching network. The switch switches the plurality of transmit filters to be coupled to the power amplifier. The plurality of first matching networks are coupled between the plurality of transmit filters and the switch. The second matching network is coupled between the power amplifier and the switch. The second matching network includes a transmission line transformer.Type: GrantFiled: August 3, 2022Date of Patent: April 8, 2025Assignee: MURATA MANUFACTURING CO., LTD.Inventors: Kenji Tahara, Syunji Yoshimi, Kazuhiro Ikarashi, Yusuke Tanaka, Kenichi Shimamoto, Masatoshi Hase
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Patent number: 12273079Abstract: Increase in power-added efficiency can be achieved. A second base of a second transistor is connected to a first collector of a first transistor. A third base of a third transistor is connected to the first collector of the first transistor, and a third collector of the third transistor is connected to a second collector of the second transistor. A second bias circuit includes a fifth transistor connected to the second base of the second transistor. A third bias circuit includes a sixth transistor connected to the third base of the third transistor. A first current limiting circuit includes a seventh transistor, a first collector resistor, and a first base resistor. A second current limiting circuit includes an eighth transistor, a second collector resistor, and a second base resistor.Type: GrantFiled: June 3, 2022Date of Patent: April 8, 2025Assignee: MURATA MANUFACTURING CO., LTD.Inventors: Kenji Tahara, Kenichi Shimamoto, Yusuke Tanaka
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Publication number: 20250092359Abstract: The present invention aims to provide a culturing method and a method for producing a cell population containing a neural crest cell, the methods being able to stably mass produce the neural crest cell from a pluripotent stem cell with quality that allows the cell to be used in a therapy with a cell, and a method for producing a mesenchymal stem cell and the like using the neural crest cell. The method for selectively culturing a neural crest cell in a cell population containing a neural crest cell and/or a neural crest progenitor cell of the present invention comprises a culturing step of adherent culturing the cell population containing the neural crest cell and/or the neural crest progenitor cell, in the presence of one or more prescribed extracellular matrices.Type: ApplicationFiled: December 26, 2022Publication date: March 20, 2025Inventors: Masahiro TAHARA, Ayaka FUJIKI, Kenji YOSHIDA, Maiko KITAGAWA
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Patent number: 12247728Abstract: A composite wireless power feeding system enables a light unit to be replaced under water and includes a wireless charging system including a power feeding coil and a first power feeding circuit unit. The power feeding system includes a power reception and feeding coil, a power feeding circuit unit, a power reception circuit unit, and an energy consumption circuit unit having a power reception coil. The power feeding system includes a battery charged by electromagnetic energy induced in the power reception and feeding coil. The battery is a power source for generating electromagnetic waves in the power reception and feeding coil to induce energy in the power reception coil and thereby power the energy consumption unit.Type: GrantFiled: March 24, 2020Date of Patent: March 11, 2025Assignee: RAISONTECH INC.Inventors: Yoshinori Kuno, Yasushi Sekizawa, Kenji Tahara
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Publication number: 20250047250Abstract: A radio frequency circuit that includes a carrier amplifier, a transmission line transformer having a main line and a sub line, a signal output terminal, a voltage supply terminal and a capacitor, wherein the main line has one end connected to an output end of a peak amplifier, the main line has another end connected to the signal output terminal, the sub line has one end connected to the one end of the main line, the sub line has another end connected to the voltage supply terminal, and the peak amplifier has the output end connected to the voltage supply terminal with the capacitor interposed therebetween.Type: ApplicationFiled: October 22, 2024Publication date: February 6, 2025Applicant: Murata Manufacturing Co., Ltd.Inventors: Kenji TAHARA, Ryo WAKABAYASHI, Kae YAMAMOTO, Toshiki MATSUI
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Patent number: 12212152Abstract: A wireless power feeding system comprising a power feeder and a power receiver including a power reception coil, a power reception circuit unit for recovering energy generated in the power reception coil, and an internal secondary battery for storing energy. Electric energy is supplied from the power feeder to the power receiver by means of electromagnetic induction using a resonance phenomenon. The power receiver has an outer shape identical to that of a conventional battery, and has a power receiver housing accommodating the power reception coil, the power reception circuit unit, and the internal secondary battery. Further, the power receiver has two electrodes disposed in positions identical to those of the conventional battery. Further, the power feeder includes a power feeding base on which the power receiver can be mounted.Type: GrantFiled: February 17, 2020Date of Patent: January 28, 2025Assignee: Raisontech Inc.Inventors: Yasushi Sekizawa, Kenji Tahara
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Publication number: 20250023588Abstract: A high frequency circuit includes power amplifiers, filters including a band A in their pass bands, filters including a band B in their pass bands, and a switch circuit that switches the connection between an antenna terminal and two terminals and switches the connection between another antenna terminal and two other terminals. The output end of one power amplifier is connected to the input ends of two of the filters, the output end of one filter is connected to one of the terminals, the output end of another filter is connected to another terminal, the output end of the other power amplifier is connected to the input ends of two others of the filters, the output end of one of the other filters is connected to one of the other terminals, and the output end of another of the other filters is connected to another of the other terminals.Type: ApplicationFiled: September 30, 2024Publication date: January 16, 2025Applicant: Murata Manufacturing Co., Ltd.Inventors: Kenji TAHARA, Kae YAMAMOTO
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Publication number: 20240429871Abstract: A high-frequency module is disclosed, comprising a carrier amplifier, peak amplifiers, a transformer, a phase-shifting line, and bias circuits, all integrated into a semiconductor IC. The input terminals of the semiconductor IC are connected to the input ends of both the carrier and peak amplifiers, while the output terminals are connected to their respective output ends. The transformer has one end connected to the output terminal, with the other end connected to the output terminal via the phase-shifting line. Additionally, the bias circuits are connected to the carrier amplifier and the peak amplifiers to regulate their operation.Type: ApplicationFiled: September 4, 2024Publication date: December 26, 2024Applicant: Murata Manufacturing Co., Ltd.Inventors: Kenji TAHARA, Yuuki NAKANO, Kae YAMAMOTO
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Publication number: 20240421775Abstract: A Doherty amplification circuit includes a carrier amplifier, a peak amplifier, a phase shift circuit, a phase shift circuit connected to an output end of the peak amplifier, a transformer including an input terminal connected to an output end of the carrier amplifier, and output terminals, and a transformer including input terminals, which are respectively connected to the output terminals of the transformer, and an output terminal connected to an antenna connection terminal, in which the phase shift circuit is connected between the output terminal of the transformer and the input terminal of the transformer, and the peak amplifier and the phase shift circuit are connected between the output terminal of the transformer and the input terminal of the transformer.Type: ApplicationFiled: August 29, 2024Publication date: December 19, 2024Applicant: Murata Manufacturing Co., Ltd.Inventors: Kenji TAHARA, Kae YAMAMOTO
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Publication number: 20240405732Abstract: A high frequency circuit includes a signal input terminal and a signal output terminal; a first amplifier, a second amplifier, a third amplifier, and a fourth amplifier; and a first phase shift circuit. An input terminal of the fourth amplifier is connected to the signal input terminal, an output terminal of the fourth amplifier is connected to an input terminal of the first amplifier and an input terminal of the second amplifier, an output terminal of the second amplifier is connected to an input terminal of the third amplifier, an output terminal of the third amplifier is connected to one end of the first phase shift circuit, and the other end of the first phase shift circuit is connected to an output terminal of the first amplifier.Type: ApplicationFiled: August 14, 2024Publication date: December 5, 2024Applicant: Murata Manufacturing Co., Ltd.Inventors: Kenji TAHARA, Kae YAMAMOTO
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Publication number: 20240405735Abstract: A radio-frequency circuit includes a carrier amplifier configured to amplify radio-frequency signals in a band A, a carrier amplifier configured to amplify radio-frequency signals in a band B, peak amplifiers configured to amplify radio-frequency signals in the band A and radio-frequency signals in the band B, a transformer having an input-side coil and an output-side coil, and phase shift lines.Type: ApplicationFiled: August 16, 2024Publication date: December 5, 2024Applicant: Murata Manufacturing Co., Ltd.Inventors: Kenji TAHARA, Kae YAMAMOTO
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Patent number: 12132508Abstract: The sensitivity of a reception filter for receiving a reception signal in a second frequency band corresponding to the 4G or 5G standard is prevented from being degraded by a harmonic of a third transmission signal in a third frequency region corresponding to the 4G or 5G standard. A radio-frequency circuit includes an antenna terminal, a relay terminal, a transmission filter, a reception filter, a variable low-pass filter, and a switch. A first transmission signal in a first frequency band is input to the relay terminal. In communication using the first frequency band, the variable low-pass filter passes the first transmission signal input via the relay terminal. When another harmonic circuit performs communication using the third frequency band, the variable low-pass filter attenuates, among harmonics of the third transmission signal in the third frequency band, a harmonic input via the relay terminal.Type: GrantFiled: June 6, 2022Date of Patent: October 29, 2024Assignee: MURATA MANUFACTURING CO., LTD.Inventors: Kenji Tahara, Takahiro Eguchi, Hiroyuki Nagamori
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Patent number: 12095281Abstract: A system for performing wireless power feeding using an existing electronic device. In the present invention, a power feeder has a power feeding coil. A power receiver has a power receiving coil, a power receiving circuit unit, and a load. Electromagnetic induction using a resonance phenomenon causes the power feeder to supply an electric energy to the power receiver. A switching circuit enables the power feeding coil to periodically repeat turning on (driving state) and turning off (resonant state) of power supply. A resonant frequency of the power receiver is substantially a period combining a time of the driving state and a time of the resonant state. A resonant frequency of the power feeder is substantially a period of the time of the resonant state, and a tuning adjusting circuit performs adjustment of a resonant capacitor and a coil.Type: GrantFiled: December 16, 2020Date of Patent: September 17, 2024Assignee: Raisontech Inc.Inventors: Yasushi Sekizawa, Kenji Tahara
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Publication number: 20240305247Abstract: A power amplifier circuit includes a carrier amplifier, a peak amplifier, an external output terminal, a combiner that includes an input terminal connected to an output terminal of the power amplifier, an input terminal connected to an output terminal of the power amplifier, and an output terminal connected to the external output terminal, a bias circuit that supplies a DC bias current to the carrier amplifier, a bias circuit that supplies a DC bias current to the peak amplifier, and a current limit circuit that is connected between the power amplifier and the bias circuit and that is configured to change a magnitude of the DC bias current according to a magnitude of a power supply voltage applied to the power amplifier circuit.Type: ApplicationFiled: May 17, 2024Publication date: September 12, 2024Applicant: Murata Manufacturing Co., Ltd.Inventors: Kenji TAHARA, Takeshi KOGURE, Kae YAMAMOTO
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Publication number: 20240275412Abstract: A radio frequency circuit includes power amplifiers, an input side coil and an output side coil, a filter whose pass band is a first band, a filter whose pass band is a second band, a filter whose pass band is a third band, a switch connected between ground and a path connecting one end portion of the output side coil and the filter, a switch connected between the ground and a path connecting the other end portion of the output side coil and the filter, a switch arranged in series in the path in between the switch and the filter, and a switch arranged in series in the path connecting the filter and a path connecting the switch and the switch, wherein no switch is arranged in series in the path.Type: ApplicationFiled: April 3, 2024Publication date: August 15, 2024Applicant: Murata Manufacturing Co., Ltd.Inventors: Hiroki SHOUNAI, Kenji TAHARA
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Publication number: 20240204739Abstract: A radio frequency circuit includes a carrier amplifier, a peaking amplifier, an input-side coil, an output-side coil, harmonic reduction circuits, and a phase shift line. One end of the input-side coil is connected to the carrier amplifier, and the other end thereof is connected to the peaking amplifier. In the harmonic reduction circuit, an inductor and a capacitor that are connected in series are disposed in series on a path connecting the carrier amplifier and the ground. The harmonic reduction circuit has an inductor and a capacitor that are connected in series and an inductor connected in parallel to the capacitor. The inductor and the capacitor are disposed in series on a path connecting the peaking amplifier and the ground.Type: ApplicationFiled: February 28, 2024Publication date: June 20, 2024Applicant: Murata Manufacturing Co., Ltd.Inventors: Kenji TAHARA, Ryo WAKABAYASHI, Kae YAMAMOTO
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Publication number: 20240178804Abstract: The power amplifier circuit includes an amplifier element, a transmission line transformer (TLT) circuit including a first, second and third line, and a switching circuit including a first, second, and third terminal. One end of the first line is coupled to an output terminal of the amplifier element, and the other end of the first line is coupled to one end of the second line. The other end of the second line is coupled to the terminal. One end of the third line is coupled between the one end of the first line and the output terminal of the amplifier element. The other end of the third line is coupled to the terminal. The switching circuit includes a first switch provided between the terminal and ground and a second switch provided between the terminal and ground.Type: ApplicationFiled: February 7, 2024Publication date: May 30, 2024Applicant: Murata Manufacturing Co., Ltd.Inventors: Kenji TAHARA, Ryo WAKABAYASHI, Kae YAMAMOTO
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Publication number: 20240178868Abstract: A radio frequency circuit including power amplifiers, a transformer having an input-side coil and an output-side coil, a bias circuit connected to the power amplifiers, an output terminal connected to one end of the output-side coil, an output terminal connected to another end of the output-side coil, a switch connected between the output terminal and a ground, a switch connected between the output terminal and a ground, a phase shift line having an input end connected to an output terminal of the power amplifier and an output end connected to one end of the input-side coil, and a phase shift line having an input end connected to an output terminal of the power amplifier and an output end connected to another end of the input-side coil.Type: ApplicationFiled: February 5, 2024Publication date: May 30, 2024Applicant: Murata Manufacturing Co., Ltd.Inventors: Kenji TAHARA, Hidetaka TAKAHASHI, Kae YAMAMOTO
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Publication number: 20240177072Abstract: A reservation system is configured to make a reservation for a charging device configured to charge a vehicle. The reservation system includes a first processing unit configured to manage reservation time frames of the charging device available to a user of a shop, a second processing unit configured to manage providing time frames of a service from a service representative who provides the service to the user at the shop, and a third processing unit configured to execute a process for receiving a time frame of reservation desired by the user among time frames overlapping between available reservation time frames and available providing time frames based on the reservation time frames of the charging device managed by the first processing unit and the providing time frames of the service from the service representative managed by the second processing unit.Type: ApplicationFiled: September 19, 2023Publication date: May 30, 2024Applicant: TOYOTA JIDOSHA KABUSHIKI KAISHAInventors: Mitsuaki TOMITA, Hiroshi Ashida, Kenji Tahara, Tamaki Ozawa, Takenori Shimizu, Tetsuro Kuniyoshi
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Patent number: 11996869Abstract: A radio frequency module includes a transmit filter of Band A and Band B, a transmit amplifier, and a switch circuit and can perform CA using a transmit signal of Band A and a receive signal of Band B, a transmit band of Band B including a receive band of Band C. The switch circuit includes a switch switching connection between a common terminal and a first selection terminal, a switch switching connection between the common terminal and a second selection terminal, and a switch switching connection between the second selection terminal and a third selection terminal. The common terminal is connected to the transmit amplifier. The first selection terminal is connected to the transmit filter of Band A. The second selection terminal is connected to the transmit filter of Band B. The third selection terminal is connected to a receive path of Band C.Type: GrantFiled: April 21, 2023Date of Patent: May 28, 2024Assignee: MURATA MANUFACTURING CO., LTD.Inventors: Kenji Tahara, Toshiki Matsui