Patents by Inventor Yo Yamaguchi

Yo Yamaguchi 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).

  • Patent number: 11881887
    Abstract: A frequency converter up-converts a transmission signal in an intermediate frequency hand into a signal in a wireless frequency hand as a USB or an LSR of a local oscillation signal using the local oscillation signal. When PMhigh?1/2×IFwid?RFtx?PMhigh?1/2×CHwid, the frequency converter is configured to satisfy ?LO=PMhigh?1/2×Fwid?IFcent and IFtx=RFtx??LO. Alternatively, when PMlow+1/2×IFwid?RFtx?PMlow+1/2×CHwid, the frequency converter is configured to satisfy ?LO=PMlow+1/2×IFwid+IFcent and IFtx=?LO?RFtx.
    Type: Grant
    Filed: January 13, 2021
    Date of Patent: January 23, 2024
    Assignee: FUJIKURA LTD.
    Inventors: Yo Yamaguchi, Kiyoshi Kobayashi
  • Publication number: 20230396222
    Abstract: A variable gain amplifier includes a differential amplifier circuit having a pair of input terminals and a pair of output terminals, and a first variable attenuation circuit connected between at least one of the pair of input terminals and the pair of output terminals of the differential amplifier circuit and capable of switching a resistance value on the basis of a control signal which is input from the outside.
    Type: Application
    Filed: January 27, 2023
    Publication date: December 7, 2023
    Applicant: Fujikura Ltd.
    Inventors: Chihiro Kamidaki, Yo Yamaguchi, Tatsuo Kubo
  • Patent number: 11764468
    Abstract: A phased array antenna includes an antenna array substrate having a plurality of antenna elements. At least two beamformers are coupled to the plurality of antenna elements. At least two filters support different frequency bands and are respectively coupled to the at least two beamformers. A frequency converter is coupled to the at least two filters, the frequency converter including one intermediate frequency (IF) port and at least two radio frequency (RF) ports. The one IF port of the frequency converter is configured to support the at least two beamformers via the at least two RF ports. A first beamformer of the at least two beamformers is coupled to a first filter of the at least two filters to form a first beam in a direction different than a second beamformer of the first two beamformers coupled to a second filter of the at least two filters.
    Type: Grant
    Filed: September 7, 2021
    Date of Patent: September 19, 2023
    Assignees: INTERNATIONAL BUSINESS MACHINES CORPORATION, FUJIKURA LTD
    Inventors: Alberto Valdes Garcia, Arun Paidimarri, Bodhisatwa Sadhu, Jean-Olivier Plouchart, Xiaoxiong Gu, Christian Wilhelmus Baks, Yo Yamaguchi, Kiyoshi Kobayashi, Yoshiharu Fujisaku, Ning Guan
  • Publication number: 20230074376
    Abstract: A phased array antenna includes an antenna array substrate having a plurality of antenna elements. At least two beamformers are coupled to the plurality of antenna elements. At least two filters support different frequency bands and are respectively coupled to the at least two beamformers. A frequency converter is coupled to the at least two filters, the frequency converter including one intermediate frequency (IF) port and at least two radio frequency (RF) ports. The one IF port of the frequency converter is configured to support the at least two beamformers via the at least two RF ports. A first beamformer of the at least two beamformers is coupled to a first filter of the at least two filters to form a first beam in a direction different than a second beamformer of the first two beamformers coupled to a second filter of the at least two filters.
    Type: Application
    Filed: September 7, 2021
    Publication date: March 9, 2023
    Inventors: Alberto Valdes Garcia, Arun Paidimarri, Bodhisatwa Sadhu, Jean-Olivier Plouchart, Xiaoxiong Gu, Christian Wilhelmus Baks, Yo Yamaguchi, Kiyoshi Kobayashi, Yoshiharu Fujisaku, Ning Guan
  • Publication number: 20220399626
    Abstract: A filter circuit (1) includes a first transmission line (11), a second transmission line (12) which has an electrical length set to ½ of an electrical length of the first transmission line, a first capacitor (21), a second capacitor (22), and a third capacitor (23). Capacitances of the first capacitor, the second capacitor, and the third capacitor are set in such a manner that a circuit including the first transmission line, the second transmission line, and the first capacitor resonates in series at a predetermined fundamental frequency, a circuit including the first transmission line, the first capacitor, and the second capacitor resonates in parallel at a third harmonic frequency being a tripled frequency of the fundamental frequency, and a circuit including the second transmission line and the third capacitor resonates in series at the third harmonic frequency.
    Type: Application
    Filed: December 17, 2020
    Publication date: December 15, 2022
    Applicant: Fujikura Ltd.
    Inventor: Yo Yamaguchi
  • Patent number: 9136893
    Abstract: A receiver includes a local signal generator, a power phase adjuster, and a frequency converter so as to perform frequency conversion on signals included in a plurality of radio frequency bands. The local signal generator supplies a plurality of local signals. The power phase adjuster adjusts local signals in terms of signal power or relative phases. The frequency converter performs frequency conversion on radio frequency bands by use of local signals adjusted with the power phase adjuster, thus sorting them in a desired frequency range.
    Type: Grant
    Filed: January 12, 2011
    Date of Patent: September 15, 2015
    Assignee: Nippon Telegraph and Telephone Corporation
    Inventors: Takana Kaho, Yo Yamaguchi, Hiroyuki Shiba, Doohwan Lee, Takayuki Yamada, Kazunori Akabane, Kazuhiro Uehara
  • Publication number: 20120281718
    Abstract: A receiver includes a local signal generator, a power phase adjuster, and a frequency converter so as to perform frequency conversion on signals included in a plurality of radio frequency bands. The local signal generator supplies a plurality of local signals. The power phase adjuster adjusts local signals in terms of signal power or relative phases. The frequency converter performs frequency conversion on radio frequency bands by use of local signals adjusted with the power phase adjuster, thus sorting them in a desired frequency range.
    Type: Application
    Filed: January 12, 2011
    Publication date: November 8, 2012
    Applicant: NIPPON TELEGRAPH AND TELEPHONE CORPORATION
    Inventors: Takana Kaho, Yo Yamaguchi, Hiroyuki Shiba, Doohwan Lee, Takayuki Yamada, Kazunori Akabane, Kazuhiro Uehara
  • Patent number: 8004363
    Abstract: A wideband low-noise amplifier of the present invention is designed such that an input terminal is connected to a base of a first transistor, one terminal of a first passive element, and one terminal of a third passive element; an emitter of the first transistor is grounded; a collector of the first transistor is connected to an output terminal, a base of a second transistor, one terminal of a capacitor, and one terminal of a second passive element; the other terminal of the first passive element is connected to the other terminal of the capacitor; an emitter of the second transistor is connected to the other terminal of the third passive element; and a power terminal is connected to a collector of the second transistor and the other terminal of the second passive element, wherein impedance of the third passive element is determined based on impedance of the first transistor whose emitter size is determined to suite desired saturation level of amplification, thus establishing input impedance matching.
    Type: Grant
    Filed: May 16, 2008
    Date of Patent: August 23, 2011
    Assignee: Nippon Telegraph and Telephone Corporation
    Inventors: Munenari Kawashima, Yo Yamaguchi, Kazuhiro Uehara, Kenjiro Nishikawa
  • Publication number: 20100066452
    Abstract: A wideband low-noise amplifier of the present invention is designed such that an input terminal is connected to a base of a first transistor, one terminal of a first passive element, and one terminal of a third passive element; an emitter of the first transistor is grounded; a collector of the first transistor is connected to an output terminal, a base of a second transistor, one terminal of a capacitor, and one terminal of a second passive element; the other terminal of the first passive element is connected to the other terminal of the capacitor; an emitter of the second transistor is connected to the other terminal of the third passive element; and a power terminal is connected to a collector of the second transistor and the other terminal of the second passive element, wherein impedance of the third passive element is determined based on impedance of the first transistor whose emitter size is determined to suite desired saturation level of amplification, thus establishing input impedance matching.
    Type: Application
    Filed: May 16, 2008
    Publication date: March 18, 2010
    Applicant: NIPPON TELEGRAPH AND TELEPHONE CORPORATION
    Inventors: Munenari Kawashima, Yo Yamaguchi, Kazuhiro Uehara, Kenjiro Nishikawa
  • Patent number: 6188261
    Abstract: A programmable delay generator comprises a first ramp wave generator and a second ramp wave generator, each having the same structure as each other, each of them operating with external common clock pulses, and each of them providing potential gradient and final potential incorporated with an external set data; a comparator for comparing an output (Vs) of the first ramp wave generator and an output (Vk) of the second ramp wave generator so that an output pulse is provided when the outputs of two ramp wave generators coincide with each other; said first ramp wave generator providing a first ramp voltage (Vs) upon receipt of a first set data (S) at a predetermined time (t0); said second ramp wave generator providing a threshold voltage (Vk) upon receipt of a second set data (K) at a time which preceds at least one clock time (T) than said predetermined time (t0); said comparator providing an output pulse delayed by delay time (td) which is proportional to ratio (K/S) of said second set data (K) and said first s
    Type: Grant
    Filed: January 20, 1999
    Date of Patent: February 13, 2001
    Assignee: Nippon Telegraph and Telephone Corporation
    Inventors: Hideyuki Nosaka, Akira Minakawa, Yo Yamaguchi, Akihiro Yamagishi