Patent ID: 7215966
Filing Date: 2007-05-08
Classification: H04W

Abstract:
1. A method for enabling a node in a wireless communication network to determine its location coordinates, based on the location coordinates of at least one other node, the method comprising: controlling the node to request at least one other node to provide location coordinates either periodically or upon the node receiving at least one of a hello message, routing message, neighbor advertisement and short hello message from the said at least one other node and, in reply, controlling said at least one other node to provide the location coordinates; controlling the node to periodically evaluate time of flight messages received at the node from the at least one other node; controlling the node to estimate its own location coordinates based on the information pertaining to the location coordinates of the said at least one other node and the evaluation of the time of flight messages; assigning a respective sequence number to each respective other node; changing the sequence number of an other node when the location coordinates of that other node change; and controlling the node to check the sequence number of the other node when the node receives a time of flight message from that other node, and controlling the node to send a request to that other node to provide updated location coordinates if the sequence number is different from a sequence number for that other node that was previously received by the node.