Patent ID: 8804551

Claim:
A method of estimating the position of an electronic device, comprising: receiving an observation including the identity of at least one wireless transmitter detected by the device at the position to be estimated; comparing the observation with a plurality of records, each record comprising the identity of one or more wireless transmitters and a corresponding position, the position being based on a location or set of locations at which the one or more transmitters were detected, each record originating from a source other than the wireless transmitter which may be determined from the record; detecting a first match between the observation and a first record, the first record comprising a corresponding first position; determining a first indication of the source of the first record; detecting a second match between the observation and a second record, the second record comprising a corresponding second position; determining a second indication of the source of the second record, wherein the second indication is different from the first indication; and estimating the position of the electronic device based on at least one of the first and second positions, depending upon the first indication and the second indication: wherein the first and second indications suggest that the first record originates from a source that is more closely related to the electronic device that the source of the second record, wherein: if the second match is more specific than the first match, then the estimation of the position of the electronic device is based preferentially on the second position; otherwise the estimation is based preferentially on the first position.