Patent ID: 6275705
Filing Date: 2001-08-14
Classification: G01S,H04W

Abstract:
A mobile radio-frequency communication system, comprising:a network of at least two base stations arranged to transmit the same signals to at least one mobile radio-frequency transceiver, and receive signals from the one or more mobile radio-frequency transceivers;a reference receiver located at a fixed location a known distance from each of the base stations and including measuring means to measure the times of arrival of signals transmitted from the base stations;determination means to use the known distances and measured times to determine the relative time offsets of transmissions from each base station; andlocation means to use the determined relative time offsets to calculate the position of a mobile transceiver in the network area using techniques involving comparison of the times of arrival of signals from the base stations at the mobile transceiver;wherein the mobile transceiver calculates the impulse response of the channel and uses this information to reduce multi-path effects.