Patents by Inventor Yoshinobu Tatsuzawa

Yoshinobu Tatsuzawa 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: 4216428
    Abstract: A receiving system without antenna switching wherein signals received by two or more spaced antennas are heterodyned using local oscillation signals at frequencies spaced from each other by not less than the fundamental frequency of a modulating signal. The resultant intermediate frequency outputs are combined and detected to produce an output signal.
    Type: Grant
    Filed: May 15, 1978
    Date of Patent: August 5, 1980
    Assignees: Matsushita Electric Industrial Co., Ltd., Nippon Telegraph & Telephone Public Corp.
    Inventors: Yoshinobu Tatsuzawa, Masayuki Sakamoto, Hiromi Wasai
  • Patent number: 4114097
    Abstract: A frequency shift receiver for periodically receiving frequency shift (FS) signals while cyclically turning on and off a power supply for a preceding section of the receiver. An output from the discriminator is turned on and off in synchronism with the turning on and off of the power supply to prevent noise even when a frequency difference exists between the transmitter and receiver.
    Type: Grant
    Filed: October 28, 1975
    Date of Patent: September 12, 1978
    Assignees: Nippon Telegraph and Telephone Public Corp., Matsushita Electric Industrial Co., Ltd.
    Inventors: Noriyoshi Kubo, Takeshi Katano, Yoshinobu Tatsuzawa, Tadatoshi Hagihira, Masahiko Yamamoto, Hiromi Wasai
  • Patent number: 3974337
    Abstract: A television telephone system, wherein frequency-modulation with a low modulation index is effected by using a carrier wave of a slightly higher frequency than the maximum frequency of a video signal, and the video signal thus modulated is transmitted through a transmission line. With such system, a wide band video signal and audio signal can be transmitted without cross talk and distortion by using an ordinary telephone cable which is intended to be used only for the transmission of voice frequency signals, and communication can be achieved, with the image of the opposite party or drawing, document or the like being viewed.
    Type: Grant
    Filed: May 23, 1974
    Date of Patent: August 10, 1976
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventor: Yoshinobu Tatsuzawa