Patent ID: 9549288
Date: 2017-01-17
CPC Classifications: G01S,H04W

Claim:
1. A method of using signal times of arrival measurements from a plurality of mobile devices, the method comprising at a location server: receiving from each mobile device of the plurality of mobile devices an estimated location of the mobile device, wherein the estimated location is based, at least in part, upon Satellite Positioning System (SPS) signals received by the mobile device from SPS satellites; receiving from said each mobile device of the plurality of mobile devices a determined difference between times of arrival of a first reference signal from a first base station and a second reference signal from a second base station, wherein the determined difference between times of arrival is as determined by said each mobile device, and wherein the first and second base stations are part of a Long Term Evolution (LTE) network; determining a plurality of transmission time offsets by determining, for each of said mobile device of the plurality of mobile devices, a transmission time offset of signals from the first and second base stations based, at least in part, upon a first distance and upon a second distance and upon the determined difference between times of arrival, combining the plurality of transmission time offsets to determine an adjusted transmission time offset; and determining an estimated location of a second mobile device based, at least in part, upon a second determined difference between times of arrival at the second mobile device of a third reference signal from the first base station and a fourth reference signal from the second base station and upon the adjusted transmission time offset,