Patent ID: 8249622

Claim:
A method of determining the location of a mobile device in a network having a plurality of base stations, in which a base station communicates with the mobile device in a downlink transmission and the mobile device communicates with a base station in uplink transmission, comprising the steps of: (a) transmitting a downlink transmission from a first base station to a mobile device; (b) receiving an uplink transmission from the mobile device to a first base station at the reference station; (c) measuring a time of arrival of the uplink transmission at the reference station; (d) determining a total distance from the first base station to the reference station as a function of the time of transmission of the downlink signal and the measured time of arrival of the uplink transmission, wherein the total distance includes (a) the distance from the reference station to the mobile device and (b) the distance from the first base station to the mobile device.