Patent ID: 7317925
Filing Date: 2008-01-08
Classification: G01S,H04W

Abstract:
1. A method for determining a location of a node in a wireless communication system, the method comprising the steps of: receiving a first plurality of over-the-air signals from a first plurality of nodes, the first plurality of over-the-air signals each containing a location; calculating a first plurality of weighting factors based on a ratio of received power to transmit power; calculating a location based on the first plurality of weighting factors and the locations; receiving a second plurality of over-the-air signals from a second plurality of nodes, the second plurality of over-the-air signals each containing a location; calculating a second plurality of weighting factors based on transmit and receive powers of the second plurality of over-the-air signals; calculating an updated location based on the second plurality of weighting factors and the locations within the second plurality of over-the air signals; wherein the first plurality of nodes comprises a first plurality of reference nodes, the locations of which are known; and wherein the second plurality of nodes comprises reference nodes, the locations of which are known, and blind nodes, the locations of which are estimate; wherein the step of calculating the first plurality of weighting factors comprises the step of calculating a plurality of values for k—index for a blind node wishing to locate itself, Nr—number of reference nodes in the system, j—index for reference nodes, n P P wherein the step of calculating the location comprises the step of calculating Nb—number of blind nodes in the system, x j—index for reference nodes.