Patents by Inventor Isao Higuma

Isao Higuma 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: 7394789
    Abstract: When an access terminal is handed off, requested-data-rate information based on a data rate control signal from each access terminal, average throughput of each access terminal before handoff, and a handoff request count are obtained from a base transceiver subsystem. A throughput after handoff of each access terminal is estimated from a ratio of the data rate information of each access terminal to the number of connected access terminals, and an estimated throughput ratio representing the degree of change from the average throughput of each access terminal before handoff to the estimated throughput is calculated. If the estimated throughput ratio is lower than or equal to a given value, the corresponding access terminal is not handed off. If the estimated throughput ratio is higher than the given value, the access terminal having the highest estimated throughput among access terminals requesting handoff is handed off.
    Type: Grant
    Filed: January 20, 2005
    Date of Patent: July 1, 2008
    Assignee: Hitachi Communication Technologies, Inc.
    Inventors: Kozo Sakawa, Masayoshi Tateno, Isao Higuma
  • Publication number: 20060029021
    Abstract: Handoff is conventionally carried out in accordance with radio reception statuses such as C/I, so that handoff to a congested station can be made, resulting in a decrease in throughput. When an access terminal is handed off, requested-data-rate information based on a data rate control signal from each access terminal, average throughput of each access terminal before handoff, and a handoff request count are obtained from a base transceiver subsystem. A throughput after handoff of each access terminal is estimated from a ratio of the data rate information of each access terminal to the number of connected access terminals, and an estimated throughput ratio representing the degree of change from the average throughput of each access terminal before handoff to the estimated throughput is calculated. If the estimated throughput ratio is lower than or equal to a given value, the corresponding access terminal is not handed off.
    Type: Application
    Filed: January 20, 2005
    Publication date: February 9, 2006
    Applicant: Hitachi Communication Technologies, Inc.
    Inventors: Kozo Sakawa, Masayoshi Tateno, Isao Higuma