Patents Assigned to The Guide Dogs for the Blind Association
  • Method and apparatus for distance measurement
    Patent number: 6404703
    Abstract: A method and apparatus for distance measurement is disclosed in which first and second signals having different propagation speeds are transmitted between a transmitter (2) at a first location and a receiver (3) at a second location. The distance between the first and second locations is determined from the difference in propagation time between the first and second signals.
    Type: Grant
    Filed: July 6, 1999
    Date of Patent: June 11, 2002
    Assignee: The Guide Dogs for the Blind Association
    Inventor: Christopher Simon Burrell