Patents by Inventor Mitsukazu Oyama

Mitsukazu Oyama 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: 5732125
    Abstract: To perform control of a mobile telephone system which uses a dedicated control channel type multichannel access system, when an emergency telephone call is made from a mobile telephone to the police or fire department, the mobile telephone references a memory into which is stored the identification code of a service area within which calling is permitted, the base station having the highest received field strength of the control channel radio signals of base stations in this service area is selected and the emergency call is made to the thus selected base station. When doing this, the mobile telephone stores the identification code of the base station to which the emergency call was made, and when a next call is made after the emergency call is completed, the call signal is sent on the control channel of the base station to which the emergency call was made, based on the thus stored identification code of the base station.
    Type: Grant
    Filed: July 28, 1995
    Date of Patent: March 24, 1998
    Assignee: Fujitsu Limited
    Inventor: Mitsukazu Oyama
  • Patent number: 4979204
    Abstract: A radio telephone system includes a subscriber exchanger accommodating a plurality of subscribers and a plurality of emergency call receiving devices each having a transmission function, a line exchanger interfacing with the subscriber exchanger, emergency speech office lines provided between the subscriber exchanger and the line exchanger, a plurality of channels coupling mobile stations and the line exchanger, and emergency speech extension lines coupled to the line exchanger and corresponding to the emergency speech office lines one by one.
    Type: Grant
    Filed: January 8, 1990
    Date of Patent: December 18, 1990
    Assignee: Fujitsu Limited
    Inventor: Mitsukazu Oyama
  • Patent number: 4021609
    Abstract: In the receiving terminal of a PCM (Pulse Code Modulation)-TDMA (Time Division Multiple Access) system, a data is demodulated from a received burst signal, said data is written in a buffer register by using a burst clock which is regenerated from the received burst signal. The content of said buffer register is read by using a local clock which is generated in the receiving office and, after the data is read out, said data is controlled by said local clock.
    Type: Grant
    Filed: August 20, 1975
    Date of Patent: May 3, 1977
    Assignee: Fujitsu Ltd.
    Inventors: Mitsukazu Oyama, Yoshiro Tada, Yasuhiko Sakamoto