Patents by Inventor Seiko Shimogama

Seiko Shimogama 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: 6577880
    Abstract: Even if traffic concentrates on a specific place in a cellular radio communication in which a base station communicates with its corresponding wireless terminal, power to be used up or consumed by the base station can be restricted. Further, the equality of communication is satisfactory and the need for a change in the conventional wireless terminal is eliminated. Therefore, two types of sectors corresponding to a wide range sector and narrow range sectors each overlapping with the wide range sector are defined in a multi-sector model. Further, a wide range antenna for the wide range sector and narrow range antennas for the narrow range sectors are separately prepared for the base station. Afterwards, signals are transmitted to wireless terminals located within the narrow range sectors by using both the wide range antenna and the narrow range antennas. In the case of CDMA in particular, the same signal is transmitted with respect to a traffic channel alone.
    Type: Grant
    Filed: July 19, 2000
    Date of Patent: June 10, 2003
    Assignee: Hitachi, Ltd.
    Inventors: Kazuhito Ishida, Seiko Shimogama, Toshiaki Kurokawa, Tsutomu Yamaguchi