Patents by Inventor Masaki Suto

Masaki Suto 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).

  • Publication number: 20030084677
    Abstract: An electronic apparatus includes a thermally insulated vessel having a cooling part therein. Disposed inside the thermally insulated vessel are a first electronic part and a second electronic part. The second electronic part is spaced apart from the cooling part while the first electronic part is in direct contact with the cooling part, such that the two electronic parts can operate at different cooling temperatures.
    Type: Application
    Filed: October 4, 2002
    Publication date: May 8, 2003
    Applicant: Hitachi Kokusai Electric Inc.
    Inventors: Noriyuki Kagaya, Yoichi Okubo, Masaki Suto, Hideaki Takahashi, Takashi Uchida
  • Publication number: 20030085761
    Abstract: A distortion reducing circuit compensates an upper side third-order distortion and a lower side third-order distortion produced by an amplifier for amplifying a fundamental signal including multiple frequency components. The distortion reducing circuit includes a second harmonic reflection coefficient regulation circuit, installed at an output side of the amplifier, for regulating reflection coefficients for multiple frequency components included in a second harmonic signal to have a constant value.
    Type: Application
    Filed: May 24, 2002
    Publication date: May 8, 2003
    Applicant: Hitachi Kokusai Electric Inc.
    Inventors: Yoichi Okubo, Kiyoshi Funada, Masaki Suto, Masato Horaguchi, Toshio Takada, Naoki Hongo
  • Publication number: 20030085762
    Abstract: A distortion compensation circuit reduces an unbalance between higher and lower 3rd order distortions, the distortions being generated by an amplifier which amplifies an input signal having at least two frequency components. Amplitude modulation means, which includes an amplitude detector, an amplitude circuit, a phase circuit and another amplitude circuit, generates sideband signals corresponding to an instantaneous phase difference between the higher and lower 3rd order distortions, such that distortions generated by the amplifier can be cancelled. Further, sideband signal generating means, which includes an amplitude circuit, a delay circuit, an AM modulator, another amplitude circuit, another delay circuit and a PM modulator, performs AM and PM on the input signal to thereby generate sideband signals, such that distortions generated by the amplifier can be cancelled.
    Type: Application
    Filed: September 25, 2002
    Publication date: May 8, 2003
    Applicant: Hitachi Kokusai Electric Inc.
    Inventors: Toshio Takada, Yoichi Okubo, Masaki Suto, Masato Horaguchi, Naoki Hongo
  • Publication number: 20030060184
    Abstract: The radio signal receiving device that has an input terminal for inputting an input signal and an output terminal for amplifying the signal inputted to the input terminal and then outputting the signal, comprises an insulating container comprising the input terminal and the output terminal, and an amplifier that is contained in the insulating container and amplifies the signal and then outputs the signal as the output signal. Bias voltage from one of the amplifier input terminal of the amplifier and the amplifier output terminal of the amplifier is applied to the output signal outputted to the amplifier output terminal of the amplifier.
    Type: Application
    Filed: September 17, 2002
    Publication date: March 27, 2003
    Inventors: Noriyuki Kagaya, Yoichi Okubo, Masaki Suto, Takashi Uchida, Hideaki Takahashi
  • Publication number: 20030053552
    Abstract: A distortion compensator for compensating for distortion produced in an amplifier that amplifies a signal includes a signal level detection means for detecting a level of a signal to be amplified and distortion compensation means for conducting distortion compensation based on the detection result separately for each frequency band signal of multiple frequency band signals contained in the signal to be amplified. The distortion compensator improves distortion compensation performance by reducing the effect of frequency characteristics that restrict the distortion compensation performance limit.
    Type: Application
    Filed: August 19, 2002
    Publication date: March 20, 2003
    Inventors: Naoki Hongo, Yoichi Okubo, Masaki Suto, Masato Horaguchi, Toshio Takada
  • Publication number: 20030045247
    Abstract: To provide an amplifying device with reduced size, weight and cost. The amplifying device delays input signals using digital delay sections in a main signal system, performs offset rotation processing of digital input signals in carrier offset sections and power detection in a power detecting section in a control system, matches phases of a multi-carrier signal of the main signal system and a power value signal of the control system in a phase control section, and gives distortion compensation in a predistorter for canceling a nonlinear characteristic generated in an amplifier.
    Type: Application
    Filed: August 28, 2002
    Publication date: March 6, 2003
    Inventors: Naoki Hongo, Yoichi Okubo, Masaki Suto, Tetsuhiko Miyatani
  • Publication number: 20030045253
    Abstract: To provide an amplifying device which is reduced in size, weight and cost and which can improve the distortion compensation performance. In the amplifying device, input signals are each subjected to digital orthogonal modulation using an IF and further to offset rotation processing in digital orthogonal modulators, then bifurcated into a main signal system and a control system, and detection of a power value is performed at an IF band in a power detecting section of the control system. Therefore, offset rotation processing of the input signals in the power detection is not required, so that a structure for matching phases of a multi-carrier signal and a power value signal is not required, resulting in improving the distortion compensation performance without using an analog delay line.
    Type: Application
    Filed: August 28, 2002
    Publication date: March 6, 2003
    Inventors: Naoki Hongo, Yoichi Okubo, Masaki Suto, Tetsuhiko Miyatani
  • Publication number: 20030027596
    Abstract: The present invention relates to an economical and highly reliable receiving apparatus for receiving radio signal transmitted from a mobile communication terminal within radio zone. The receiving apparatus has antenna sections that receive radio signal transmitted from the mobile communication terminal and are provided in each of a plurality of sectors divided from the radio zone, and receiving units that are provided in each of the antenna sections and that perform a predetermined process to the radio signal received by the antenna section. Further, receiving apparatus has four cooling sections for receipt filter and LNA within two receiving units. Each of the cooling sections cools the same number of receipt filter and LNA.
    Type: Application
    Filed: June 20, 2002
    Publication date: February 6, 2003
    Inventors: Yoichi Okubo, Masaki Suto, Noriyuki Kagaya, Takashi Uchida, Kiyoshi Funada, Kotaro Takenaga
  • Publication number: 20030022639
    Abstract: A peak limiter for use in a system for amplifying a multi-carrier signal receives a baseband signal of each carrier of the multi-carrier signal. The multi-carrier signal is computationally estimated to have carriers combined in an RF band, and obtains power information of the multi-carrier signal to limit an amplitude of the baseband signal based on the power information of the estimated multi-carrier signal to thereby provide peak-limited baseband signals. Thus, the distortion generated by performing the unnecessary peak limitation can be effectively prevented to thereby improve the reliability of the entire system.
    Type: Application
    Filed: July 26, 2002
    Publication date: January 30, 2003
    Applicant: Hitachi Kokusai Electric Inc.
    Inventors: Naoki Hongo, Yoichi Okubo, Masaki Suto, Masato Horaguchi, Toshio Takada, Tetsuhiko Miyatani
  • Publication number: 20020180523
    Abstract: There is provided a distortion canceling circuit for reducing an unbalance between a higher and a lower 3rd order distortion at frequencies of (2·f2−f1) and (2·f1−f2), respectively, the distortions being generated by an amplifier which amplifies an input signal having at least two frequency components, i.e., f1 and f2. Phase modulation control means supply a control signal, which has a difference frequency of (f2−f1), to phase modulation means, the control signal being generated based on the amplified input signal outputted from the amplifier. The phase modulation means performs phase modulation on the amplified input signal based on the supplied control signal to thereby generate a higher and a lower side-band signal having frequencies of (2·f2−f1) and (2·f1−f2), respectively, each of which has an identical amplitude and a phase difference of 180° with respect to each other.
    Type: Application
    Filed: April 25, 2002
    Publication date: December 5, 2002
    Applicant: Hitachi Kokusai Electric Inc.
    Inventors: Yoichi Okubo, Kiyoshi Funada, Masaki Suto, Masato Horaguchi, Toshio Takada, Naoki Hongo
  • Publication number: 20020101938
    Abstract: To update the control value to a value of higher precision in a predistortion type distortion compensation apparatus for compensating the distortion occurring in an amplifier for amplifying an input signal by the control using a control value corresponding to the level of the input signal.
    Type: Application
    Filed: June 15, 2001
    Publication date: August 1, 2002
    Inventors: Masato Horaguchi, Naoki Hongo, Takashi Uchida, Masaki Suto, Toshio Takada
  • Patent number: 6388689
    Abstract: The formation of a high-quality image at a resolution at which a dot size is smaller than the diameter of a laser beam is attained at a low cost. When an exposure operation is carried out by increasing an optical intensity of a laser beam to a level higher than that of a steady-state optical intensity thereof by utilizing a difference, which is ascribed to an exposure rate of a photosensitive body, in the condition of a latent image formed, the depth and width of a latent image, which were small in all related art cases, can be increased to high levels. Therefore, overshoot is generated at the LD lighting starting time to increase the optical intensity at a rising edge of the laser beam to a level higher than that of a steady-state optical intensity thereof, whereby a height to width ratio and the reproducibility of one dot and a halftone in a case where the resolution is smaller than the diameter of the laser beam can be improved.
    Type: Grant
    Filed: July 31, 2000
    Date of Patent: May 14, 2002
    Assignee: Fuji Xerox Co., Ltd.
    Inventors: Tsuneo Toda, Masaki Suto
  • Publication number: 20020022464
    Abstract: Disclosed is an amplifier apparatus that corrects mismatching of the filter transmission characteristic due to a change in the temperature of the amplifier apparatus itself and thereby stably amplifies the high-frequency signal. The amplifier apparatus converts a signal to be processed into one having an intermediate frequency band to thereby execute amplification processing.
    Type: Application
    Filed: October 11, 2001
    Publication date: February 21, 2002
    Inventors: Takashi Uchida, Masaki Suto, Shoji Fujimoto, Junetsu Urata, Hidefumi Ito
  • Patent number: 6282385
    Abstract: A control unit is configured in such a manner that at a transition from a developing state to a non-developing state both of DC and AC components of a development bias that are superimposed on each other are instantaneously interrupted after the duty factor of the portion of the AC component having the opposite polarity to the developer charging polarity is gradually increased.
    Type: Grant
    Filed: August 1, 2000
    Date of Patent: August 28, 2001
    Assignee: Fuji Xerox Co., Ltd.
    Inventor: Masaki Suto
  • Patent number: 6271723
    Abstract: A distortion compensating device comprises a 3 dB coupler having four terminals. The first terminal supplies an input signal to be inputted to an amplifier or is supplied with an input signal from an amplifier. The second terminal is associated with a third-order distortion generator for generating a third-order distortion having an amplitude for canceling out a third-order distortion generated by the amplifier depending on the supplied input signal. The third terminal is associated with a phase adjuster for adjusting the phase of the input signal to set the phase difference between the input signal and the third-order distortion generated by the third-order distortion generator to a phase difference for canceling out the third-order distortion generated by the amplifier.
    Type: Grant
    Filed: February 24, 2000
    Date of Patent: August 7, 2001
    Assignee: Kokusai Electric Co., Ltd.
    Inventors: Terufumi Nagano, Yoichi Okubo, Yasuo Sera, Masaki Suto, Hidefumi Ito