Patents Examined by Maro E. Bookbinder
  • Patent number: 4710975
    Abstract: A space diversity reception system which minimizes the inband amplitude and/or phase dispersion by controlling the phase shifter is described. According to the present invention, the interference waves in the two antenna outputs are combined in anti-phase condition. The phase shifter control direction is decided by the sign of the two parameters. One of them is difference between two antenna levels at the center frequency of the pass-band, and the other is the difference of the combined signal levels at the extreme edges of the pass-band. The control means comprises four detectors for detecting said levels, two subtractors for providing said level differences between them, and the control circuit for deciding the phase shifter control direction.
    Type: Grant
    Filed: April 5, 1982
    Date of Patent: December 1, 1987
    Assignee: Nippon Telegraph & Telephone Public Corp.
    Inventors: Yoshiharu Okamoto, Izumi Horikawa, Shozo Komaki