Patents by Inventor Tatsuto Oka

Tatsuto Oka 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: 8036303
    Abstract: A transmitter apparatus capable of reducing the distortions of vector modulated waves. This apparatus includes variable coefficient filters (110,112) in a stage preceding an amplitude signal voltage generating part (104) and also includes variable coefficient filters (111,113) in a stage preceding a phase modulated wave generating part (105). These variable coefficient filters (110-113) are used to perform a pulse shaping, thereby adjusting the delay between an amplitude component modulated signal (r(t)) and a phase component modulated signal (SC(t)) whereby a resolution, which is finer than the sampling period of a signal processing, can be used to adjust the delay time difference between the amplitude component modulated signal (r(t)) and the phase component modulated signal (SC(t)). As a result, the distortions of vector modulated waves (Srf(t)) can be reduced to a sufficiently small level.
    Type: Grant
    Filed: December 15, 2006
    Date of Patent: October 11, 2011
    Assignee: Panasonic Corporation
    Inventor: Tatsuto Oka
  • Publication number: 20100220770
    Abstract: A transmitter apparatus capable of reducing the distortions of vector modulated waves. This apparatus includes variable coefficient filters (110,112) in a stage preceding an amplitude signal voltage generating part (104) and also includes variable coefficient filters (111,113) in a stage preceding a phase modulated wave generating part (105). These variable coefficient filters (110-113) are used to perform a pulse shaping, thereby adjusting the delay between an amplitude component modulated signal (r(t)) and a phase component modulated signal (SC(t)) whereby a resolution, which is finer than the sampling period of a signal processing, can be used to adjust the delay time difference between the amplitude component modulated signal (r(t)) and the phase component modulated signal (SC(t)). As a result, the distortions of vector modulated waves (Srf(t)) can be reduced to a sufficiently small level.
    Type: Application
    Filed: December 15, 2006
    Publication date: September 2, 2010
    Applicant: Matsushita Electric Industrial Co., Ltd.
    Inventor: Tatsuto Oka
  • Patent number: 7358829
    Abstract: Transmission apparatus capable of reducing distortion of the vector modulation wave that is the transmission output to a sufficiently small level is provided. An amplifying section (105) generates a vector modulation wave based on an amplitude component modulation signal and a phase modulation wave. A synchronous demodulating section (107) detects the vector modulation wave, generates a synchronous demodulation signal, and sends this to a band filtering section (108). The band filtering section (108) extracts a signal of the frequency component of the distortion from a synchronous demodulation signal outputted by the synchronous demodulating section (107).
    Type: Grant
    Filed: March 21, 2006
    Date of Patent: April 15, 2008
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventor: Tatsuto Oka
  • Patent number: 7333582
    Abstract: A two-point frequency modulation apparatus is provided that reduces input timing difference and improves modulation accuracy. Two-point frequency modulation apparatus 10 has: PLL circuit 11; frequency division ratio generator 13 that generates the frequency division ratio in frequency divider 111 based on first digital baseband signal S1 and carrier signal; adder 114 that adds second digital baseband signal S2 to the output signal of loop filter 113; a delay index calculator (filter coefficient calculator 17) that calculates the delay index based on the magnitude of change in the amplitude of the output signal of adder 114; and a delay adjuster (digital filter 18) that shifts the phase of one of first digital baseband signal S1 and second digital baseband signal S2 according to the delay index so as to reduce the phase difference.
    Type: Grant
    Filed: February 28, 2005
    Date of Patent: February 19, 2008
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Hiroyuki Yoshikawa, Shunsuke Hirano, Tatsuto Oka
  • Publication number: 20060234652
    Abstract: Transmission apparatus capable of reducing distortion of the vector modulation wave that is the transmission output to a sufficiently small level is provided. An amplifying section (105) generates a vector modulation wave based on an amplitude component modulation signal and a phase modulation wave. A synchronous demodulating section (107) detects the vector modulation wave, generates a synchronous demodulation signal, and sends this to a band filtering section (108). The band filtering section (108) extracts a signal of the frequency component of the distortion from a synchronous demodulation signal outputted by the synchronous demodulating section (107).
    Type: Application
    Filed: March 21, 2006
    Publication date: October 19, 2006
    Applicant: MATSUSHITA ELECTRIC INDUSTRIAL CO., LTD.
    Inventor: Tatsuto Oka
  • Publication number: 20050232385
    Abstract: A two-point frequency modulation apparatus is provided that reduces input timing difference and improves modulation accuracy. Two-point frequency modulation apparatus 10 has: PLL circuit 11; frequency division ratio generator 13 that generates the frequency division ratio in frequency divider 111 based on first digital baseband signal S1 and carrier signal; adder 114 that adds second digital baseband signal S2 to the output signal of loop filter 113; a delay index calculator (filter coefficient calculator 17) that calculates the delay index based on the magnitude of change in the amplitude of the output signal of adder 114; and a delay adjuster (digital filter 18) that shifts the phase of one of first digital baseband signal S1 and second digital baseband signal S2 according to the delay index so as to reduce the phase difference.
    Type: Application
    Filed: February 28, 2005
    Publication date: October 20, 2005
    Applicant: MATSUSHITA ELECTRIC INDUSTRIAL CO., LTD.
    Inventors: Hiroyuki Yoshikawa, Shunsuke Hirano, Tatsuto Oka