Patents by Inventor Junya Dosaka

Junya Dosaka 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: 9991849
    Abstract: A wireless communication device configured to prevent a transmission time period for sending a wireless signal and a receiving time period for receiving a wireless signal from being overlap, comprises: a transmitter that includes an orthogonal modulator that orthogonally modulates an IQ-modulated modulation signal and a transmission power amplifier that power-amplifies the orthogonally modulated signal; a receiver that includes a demodulator that demodulates a received signal; a first power source that is the power source for the transmission power amplifier and the receiver; and a second power source that is the power source for the orthogonal modulator; and a controller which outputs the modulation signal to the orthogonal modulator. The first power source outputs a constant voltage to the receiver during the receiving time period, and outputs, during the transmission time period, to the transmission power amplifier, a fluctuating voltage according to an envelope of the modulation signal.
    Type: Grant
    Filed: September 29, 2014
    Date of Patent: June 5, 2018
    Assignee: Hitachi Kokusai Electric Inc.
    Inventor: Junya Dosaka
  • Patent number: 9882536
    Abstract: Provided is a technique for effectively implementing DC removal during switching of transmission scheme or transmission data in a wireless apparatus equipped with a function for supplying a voltage to a power amplifier by ET control. When the ET control is not carried out in a power supply unit, more specifically, when an IQ signal is not present, a control unit outputs a pulse width modulation (PWM) signal for a fixed voltage via a switch unit. In other words, the switch unit selectively supplies a PWM signal for ET and a PWM signal for the fixed voltage to a switching amplifier. The switching amplifier is controlled by a predetermined control signal from the control unit.
    Type: Grant
    Filed: September 5, 2014
    Date of Patent: January 30, 2018
    Assignee: HITACHI KOKUSAI ELECTRIC INC.
    Inventor: Junya Dosaka
  • Publication number: 20170294879
    Abstract: A wireless communication device configured to prevent a transmission time period for sending a wireless signal and a receiving time period for receiving a wireless signal from being overlap, comprises: a transmitter that includes an orthogonal modulator that orthogonally modulates an IQ-modulated modulation signal and a transmission power amplifier that power-amplifies the orthogonally modulated signal; a receiver that includes a demodulator that demodulates a received signal; a first power source that is the power source for the transmission power amplifier and the receiver; and a second power source that is the power source for the orthogonal modulator; and a controller which outputs the modulation signal to the orthogonal modulator. The first power source outputs a constant voltage to the receiver during the receiving time period, and outputs, during the transmission time period, to the transmission power amplifier, a fluctuating voltage according to an envelope of the modulation signal.
    Type: Application
    Filed: September 29, 2014
    Publication date: October 12, 2017
    Applicant: Hitachi Kokusai Electric Inc.
    Inventor: Junya DOSAKA
  • Publication number: 20160226453
    Abstract: Provided is a technique for effectively implementing DC removal during switching of transmission scheme or transmission data in a wireless apparatus equipped with a function for supplying a voltage to a power amplifier by ET control. When the ET control is not carried out in a power supply unit, more specifically, when an IQ signal is not present, a control unit outputs a pulse width modulation (PWM) signal for a fixed voltage via a switch unit. In other words, the switch unit selectively supplies a PWM signal for ET and a PWM signal for the fixed voltage to a switching amplifier. The switching amplifier is controlled by a predetermined control signal from the control unit.
    Type: Application
    Filed: September 5, 2014
    Publication date: August 4, 2016
    Inventor: Junya DOSAKA
  • Patent number: 8698620
    Abstract: A wireless communications device for performing wireless communications includes a notifying unit for notifying a user of a status of the corresponding wireless communications device when a dedicated user interface is manipulated, a display unit and a detector for detecting failure in the display unit. The notifying unit notifies the user of the status of the corresponding wireless communications device when a failure in the display unit is detected by the detector and prevents the status of the corresponding wireless communications device from being notified when the failure in the display unit is not detected by the detector.
    Type: Grant
    Filed: December 24, 2009
    Date of Patent: April 15, 2014
    Assignee: Hitachi Kokusai Electric Inc.
    Inventors: Junya Dosaka, Osamu Sato, Hideyuki Yanagiya
  • Patent number: 8035444
    Abstract: An amplifier capable of lowering an electrical current flowing in a peak amplifier before a carrier amplifier becomes saturated to thereby improve the efficiency of an entirety of the amplifier is provided. The amplifier includes a carrier amplifier circuit having an amplifying element operable in class-AB or class-B, and a plurality of peak amplifier circuits which have amplifying elements operating in class-B or class-C and which are arranged to start an operation in stages in response to an input level. An output of the carrier amplifier circuit and outputs of the peak amplifier circuits are combined together for signal output. One of the peak amplifier circuits which is rendered operative at the lowest input level is smaller in saturation output than the carrier amplifier circuit.
    Type: Grant
    Filed: November 10, 2009
    Date of Patent: October 11, 2011
    Assignee: Hitachi Kokusai Electric Inc.
    Inventors: Yoichi Okubo, Manabu Nakamura, Yasuhiro Takeda, Taizo Ito, Junya Dosaka, Terufumi Nagano, Hidekatsu Ueno, Toshio Nojima
  • Patent number: 8030995
    Abstract: A power circuit used for an amplifier, which includes an amplifier provided with a linear amplifier serving as a voltage source, a DC/DC converter serving as a current source, a hysteresis comparator controlling the DC/DC converter, and a current detector detecting output current from the linear amplifier to output the detected output current to the hysteresis comparator; and a switching restricting device for restricting a switching interval in the DC/DC converter such that the switching interval is not equal to or less than a constant time or is not shorter than the constant time.
    Type: Grant
    Filed: December 22, 2009
    Date of Patent: October 4, 2011
    Assignee: Hitachi Kokusai Electric Inc.
    Inventors: Yoichi Okubo, Manabu Nakamura, Junya Dosaka, Yasuhiro Takeda, Taizo Ito, Naoki Hongo, Taizo Yamawaki, Takashi Kawamoto, Akira Maeki
  • Publication number: 20100171553
    Abstract: A power circuit used for an amplifier, which includes an amplifier provided with a linear amplifier serving as a voltage source, a DC/DC converter serving as a current source, a hysteresis comparator controlling the DC/DC converter, and a current detector detecting output current from the linear amplifier to output the detected output current to the hysteresis comparator; and a switching restricting means for restricting a switching interval in the DC/DC converter such that the switching interval is not equal to or less than a constant time or is not shorter than the constant time.
    Type: Application
    Filed: December 22, 2009
    Publication date: July 8, 2010
    Inventors: Yoichi Okubo, Manabu Nakamura, Junya Dosaka, Yasuhiro Takeda, Taizo Ito, Naoki Hongo, Taizo Yamawaki, Takashi Kawamoto, Akira Maeki
  • Publication number: 20100156648
    Abstract: A wireless communications device for performing wireless communications includes a notifying unit for notifying a user of a status of the corresponding wireless communications device when a dedicated user interface is manipulated, a display unit and a detector for detecting failure in the display unit. The notifying unit notifies the user of the status of the corresponding wireless communications device when a failure in the display unit is detected by the detector and prevents the status of the corresponding wireless communications device from being notified when the failure in the display unit is not detected by the detector.
    Type: Application
    Filed: December 24, 2009
    Publication date: June 24, 2010
    Applicant: Hitachi Kokusai Electric Inc.
    Inventors: Junya Dosaka, Osamu Sato, Hideyuki Yanagiya
  • Publication number: 20100117726
    Abstract: An amplifier capable of lowering an electrical current flowing in a peak amplifier before a carrier amplifier becomes saturated to thereby improve the efficiency of an entirety of the amplifier is provided. The amplifier includes a carrier amplifier circuit having an amplifying element operable in class-AB or class-B, and a plurality of peak amplifier circuits which have amplifying elements operating in class-B or class-C and which are arranged to start an operation in stages in response to an input level. An output of the carrier amplifier circuit and outputs of the peak amplifier circuits are combined together for signal output. One of the peak amplifier circuits which is rendered operative at the lowest input level is smaller in saturation output than the carrier amplifier circuit.
    Type: Application
    Filed: November 10, 2009
    Publication date: May 13, 2010
    Applicant: HITACHI KOKUSAI ELECTRIC INC.
    Inventors: Yoichi OKUBO, Manabu NAKAMURA, Yasuhiro TAKEDA, Taizo ITO, Junya DOSAKA, Terufumi NAGANO, Hidekatsu UENO, Toshio NOJIMA
  • Patent number: 7626455
    Abstract: A distortion compensation apparatus includes distortion generating means for generating distortions to compensate for a distortion generated in an amplifier 2. The distortion generating means includes a nonlinear circuit 13 having an input/output expansion characteristic as a circuit which generates a distortion of the lowest odd order as a compensation target and also includes a nonlinear circuit 18 having an input/output saturation characteristic as a circuit which generates a distortion of another odd order as a compensation target.
    Type: Grant
    Filed: April 1, 2008
    Date of Patent: December 1, 2009
    Assignee: Hitachi Kokusai Electric, Inc.
    Inventors: Taizo Ito, Yoichi Okubo, Junya Dosaka, Toshio Nojima
  • Publication number: 20090015326
    Abstract: A distortion compensation apparatus includes distortion generating means for generating distortions to compensate for a distortion generated in an amplifier 2. The distortion generating means includes a nonlinear circuit 13 having an input/output expansion characteristic as a circuit which generates a distortion of the lowest odd order as a compensation target and also includes a nonlinear circuit 18 having an input/output saturation characteristic as a circuit which generates a distortion of another odd order as a compensation target.
    Type: Application
    Filed: April 1, 2008
    Publication date: January 15, 2009
    Inventors: Taizo ITO, Yoichi OKUBO, Junya DOSAKA, Toshio NOJIMA
  • Patent number: 7436259
    Abstract: An amplification apparatus that has a distortion detection loop that detects distortion components contained in an amplified signal to be amplified that is amplified by an amplifier 3, and a distortion removal loop that removes distortion components from the amplified signal, using the distortion components detected by the distortion detection loop, combines a reference signal (pilot signal) with the signal to be amplified, and performs control relating to distortion compensation, using said reference signal, to provide improved efficiency with respect to a configuration to perform control relating to distortion compensation, using a reference signal. A signal to be amplified is detected by amplification signal detection means 11˜13 and 21, and when it is detected by the amplification signal detection means that there is no input of a signal to be amplified, reference signal control means 21, 15 perform control to effect non-output of the reference signals.
    Type: Grant
    Filed: May 18, 2004
    Date of Patent: October 14, 2008
    Assignee: Hitachi Kokusai Electric Inc.
    Inventors: Ryoki Haramoto, Junya Dosaka
  • Patent number: 7375588
    Abstract: A transmission amplifier for amplifying a signal to be transmitted includes an amplifying unit that is warmed efficiently when the temperature is low. In a constitution in which an amplifying unit amplifies a signal, a temperature detecting means detects temperature. Amplifying-unit-self-heating-facilitation control means perform control for facilitating self-heating by the amplifying unit when temperature detected by the temperature detecting means is lower than a predetermined threshold value, or equal to or lower than the predetermined threshold value. The amplifying-unit-self-heating-facilitation control means perform, for example, bias control for the amplifying unit as the control for facilitating self-heating by the amplifying unit.
    Type: Grant
    Filed: March 23, 2004
    Date of Patent: May 20, 2008
    Assignee: Hitachi Kokusai Electric Inc.
    Inventors: Junichiro Yamakawa, Junya Dosaka
  • Publication number: 20080055000
    Abstract: An amplification apparatus that has a distortion detection loop that detects distortion components contained in an amplified signal to be amplified that is amplified by an amplifier 3, and a distortion removal loop that removes distortion components from the amplified signal, using the distortion components detected by the distortion detection loop, combines a reference signal (pilot signal) with the signal to be amplified, and performs control relating to distortion compensation, using said reference signal, to provide improved efficiency with respect to a configuration to perform control relating to distortion compensation, using a reference signal. A signal to be amplified is detected by amplification signal detection means 11˜13 and 21, and when it is detected by the amplification signal detection means that there is no input of a signal to be amplified, reference signal control means 21, 15 perform control to effect non-output of the reference signals.
    Type: Application
    Filed: May 18, 2004
    Publication date: March 6, 2008
    Inventors: Ryoki Haramoto, Junya Dosaka
  • Publication number: 20060214730
    Abstract: In a transmission amplifier for amplifying a signal to be transmitted, an amplifying unit is warmed efficiently when temperature is low. In a constitution in which an amplifying unit 1 amplifies a signal, temperature detecting means 4 detects temperature. Amplifying-unit-self-heating-facilitation control means 2 and 5 perform control for facilitating self-heating by the amplifying unit 1 when temperature detected by the temperature detecting means 4 is lower than a predetermined threshold value or equal to or lower than the predetermined threshold value. The amplifying-unit-self-heating-facilitation control means 2 and 5 perform, for example, bias control for the amplifying unit 1 as the control for facilitating self-heating by the amplifying unit 1.
    Type: Application
    Filed: March 23, 2004
    Publication date: September 28, 2006
    Inventors: Junichiro Yamakawa, Junya Dosaka
  • Patent number: 6417731
    Abstract: Excellent compensation of the distortion is realized with a distortion-compensated amplifier device that compensates a distortion that is generated in a main amplifier, through the respective operations of a circuit comprised of a distortion-detecting loop and a distortion-compensating loop and a pre-distortor. In a distortion-detecting loop, the signal is distributed. With respect to one distribution signal, a vector adjuster (2) performs vector adjustment of it and the pre-distortor (3) generates a distortion. A main amplifier (4) amplifies this signal. The resulting amplification signal and the other distribution are composed, whereby a distortion component is detected. In a distortion-compensating loop, that amplification signal and this distortion component are composed to thereby eliminate the distortion component from the amplification signal. In a control part, a distortion component level detecting means (12) detects the levels of the distortion component that is detected.
    Type: Grant
    Filed: March 29, 2001
    Date of Patent: July 9, 2002
    Assignee: Hitachi Kokusai Electric Inc.
    Inventors: Kiyoshi Funada, Junichiro Yamakawa, Junya Dosaka, Yasuo Sera