Patents by Inventor Hiromi Wasai

Hiromi Wasai 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).

  • Pulse signal receiving system employing space diversity
    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
  • Frequency shift signal receiver
    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
  • Digital mobile communication system and method
    Patent number: 4032846
    Abstract: A unique carrier frequency allocation in a digital mobile communication system having a service area consisting of a number of radio coverage zones is disclosed. A single standard carrier frequency is used in the service area but the carrier frequencies are arranged to be slightly shifted relative to each other for stations in adjacent radio coverage zones in order to improve the receiving efficiency in a region covered by overlapping zones. The invention defines a condition for the shift frequencies for the radio coverage zones.
    Type: Grant
    Filed: October 8, 1975
    Date of Patent: June 28, 1977
    Assignee: Nippon Telegraph and Telephone Public Corporation
    Inventors: Kenkichi Hirade, Takeshi Hattori, Hiromi Wasai