Patent ID: 7254401
Filing Date: 2007-08-07
Classification: G01S,H04W

Abstract:
1. A method for determining a geographic location of a user equipment via a location service server in a wireless network, comprising the steps of: (a1) receiving, by the wireless network, a request for locating a user equipment; (a2) determining if the user equipment is in active communication with a connected transceiver node in response to said request for locating a user equipment, requesting a connection between the user equipment and a selected transceiver node if the user equipment is not in active communication with any transceiver node, and connecting the selected transceiver node with the user equipment so that the selected transceiver node comprises a connected transceiver node; (a) determining a value of the transmission timing delay of the user equipment; (b) measuring a round trip time of a radio signal between the connected transceiver node and the user equipment, wherein the connected transceiver node is in active communication with the user equipment; (c) measuring a round trip time of a radio signal between at least one other transceiver node and the user equipment, wherein the at least one other transceiver node is not in active communication with the user equipment; (d) calculating a distance between the user equipment and the connected transceiver node and between the user equipment and each of the at least one other transceiver node using the transmission timing delay determined in said step (a); and (e) determining the location of the user equipment using the distances calculated in said step (d).