Patent ID: 8175620

Claim:
A method of assigning geographical coordinates to a grid point located in a geographic region for the location of a mobile device, comprising: (a) providing calibration data for each of one or more calibration points in the geographic region; (b) for each of said calibration points: (i) evaluating the associated calibration data; (ii) determining if at least one grid point should be defined based on said evaluation; and (iii) assigning geographical coordinates to said at least one grid point, (c) determining geographical coordinates for each of a plurality of nodes of a uniform grid spanning said geographic region; and (d) for each of said at least one grid point: (i) determining a closest node from said plurality of nodes; and (ii) assigning characteristic data associated with said grid point to said closest node, wherein for each of select ones of said calibration points the calibration data includes plural data vectors and the evaluating of said calibration data comprises a determination of clustering of said plural data vectors, and wherein said characteristic data comprises data selected from the group consisting of: a list of cells neighboring a cell serving said mobile device; a quantity that is a function of a power level of one or more cells neighboring a cell serving said mobile device; an identity of a cell or a sector serving said mobile device; a timing advance parameter; a geographical orientation of said mobile device; a location of said mobile device; network measurement report data vectors; a state of a network serving said mobile device; a confidence measure indicative of a reliability of the calibration data; and combinations thereof.