Patents by Inventor Tsunetoshi Mizusawa

Tsunetoshi Mizusawa 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).

  • VoIP gateway device and digital one-link tandem exchange method
    Patent number: 7039059
    Abstract: A VoIP (Voice over IP network) gateway device includes an identification pattern inserting section, identification pattern detecting section, pass through frame assembly section, and pass through frame processing section. The identification pattern inserting section inserts an identification pattern of a predetermined bit pattern in a receiving signal from an IP transit trunk, and sends out the signal to a digital exchange. The identification pattern detecting section detects an identification pattern from a receiving signal from the digital exchange. The pass through frame assembly section converts an RTP (Real-time Transport Protocol) packet obtained from the IP transit trunk into a digital voice signal in a pass through frame format having a bit rate of 64 kbps when the identification pattern detecting section detects an identification pattern.
    Type: Grant
    Filed: September 26, 2001
    Date of Patent: May 2, 2006
    Assignee: NEC Corporation
    Inventors: Tsunetoshi Mizusawa, Toshie Ishii
  • VoIP gateway device and digital one-link tandem exchange method
    Publication number: 20020037002
    Abstract: A VoIP (Voice over IP network) gateway device includes an identification pattern inserting section, identification pattern detecting section, pass through frame assembly section, and pass through frame processing section. The identification pattern inserting section inserts an identification pattern of a predetermined bit pattern in a receiving signal from an IP transit trunk, and sends out the signal to a digital exchange. The identification pattern detecting section detects an identification pattern from a receiving signal from the digital exchange. The pass through frame assembly section converts an RTP (Real-time Transport Protocol) packet obtained from the IP transit trunk into a digital voice signal in a pass through frame format having a bit rate of 64 kbps when the identification pattern detecting section detects an identification pattern.
    Type: Application
    Filed: September 26, 2001
    Publication date: March 28, 2002
    Applicant: NEC CORPORATION
    Inventors: Tsunetoshi Mizusawa, Toshie Ishii