Patent ID: 8520647
Filing Date: 2013-08-27
Classification: G01S,H04W

Abstract:
1. A method for determining an estimated position of mobile wireless client device in a communications environment served by a wireless communications network that comprises one or more access points, the method comprising: identifying a plurality of locations in the communications environment, each of the plurality of locations being a cell on an attenuation grid that uniquely corresponds to one of the one or more access points; building a model of the communications environment by each of the one or more access points approximating an expected received signal strength for signals output from every cell on the attenuation grid, the approximating of the expected received signal strength is performed using attenuation information including (i) manufacturer and model of an access point of the one or more access points approximating the expected received signal strength and (ii) antenna characteristics of the access point; measuring a received signal strength at the one or more access points of a signal transmitted from a first mobile wireless client device; and determining an estimated position of the first mobile wireless client device by calculating an error for each of the plurality of locations forming the attenuation grid, the error being a difference between an expected received signal strength and the received signal strength at each of the plurality of locations so that the first mobile wireless client device is determined to be located at a cell based on the error.