Patent ID: 8938262
Filing Date: 2015-01-20
Classification: H04W

Abstract:
1. A method comprising: receiving, at a mobile device, wireless signals transmitted by a plurality of transmitters; extracting identification information and non-unique signal characteristics from the wireless signals corresponding to the plurality of transmitters, wherein the identification information includes an identifier of a serving transmitter, and the non-unique signal characteristics, alone, are insufficient for uniquely identifying a transmitter; determining a location of the serving transmitter by searching the identifier in a transmitter cache; determining neighboring transmitters that are different from the serving transmitter based on the received signal information, wherein determining the identities comprises: searching the non-unique signal characteristics in the transmitter cache to identify matching transmitters, the matching transmitters including transmitters the signal characteristics of which match the non-unique signal characteristics extracted from the wireless signals; determining locations of the neighboring matching transmitters using signal transmitter records for the matching transmitters as stored in the transmitter cache; and designating one or more matching transmitters the locations of which are geographically nearest to the location of the serving transmitter as the neighboring transmitters; calculating an average of the locations of the neighboring transmitters and the location of the serving transmitter, wherein calculating the average of the transmitter locations comprises: determining a respective weight of each neighboring transmitter that does not serve the mobile device, including determining a weight of the serving transmitter and applying the weight of the serving transmitter as a negative weight in determining the respective weight of each neighboring transmitter, wherein determining the weight of the serving transmitter is based on a count of the neighboring transmitters, wherein a greater count, up to a pre-specified limit, corresponds to a lower weight of the serving transmitter; and calculating the average by applying a respective weight to each transmitter location and determining a location of the mobile device based on the calculated average.