Patent ID: 6335723
Filing Date: 2002-01-01
Classification: G06F

Abstract:
A transmitter location system between a movable transmitter and a plurality of receivers, comprising:a first output signal having a first speed of propagation, said first output signal being transmitted repeatedly from said movable transmitter to at least one of said plurality of receivers; a second output signal having a second speed of propagation different from said first speed of propagation of said first output signal, said second output signal being transmitted repeatedly from said movable transmitter to each of said plurality of receivers, wherein time to reach each of said plurality of receivers is dependent on a distance between said movable transmitter and each of said plurality of receivers; and means for determining location of said movable transmitter, using said first output signal, said second output signal, and a stored prior transmitted said second output signal to calculate distance from said movable transmitter to each of said plurality of receivers.