Patent attributes
Methods and apparatus herein facilitate accurate estimation of a mobile terminal's location via location fingerprinting. Specifically, the methods and apparatus obtain a radio fingerprint of the mobile terminal's location based on signal measurements (e.g., signal strength, signal quality, or path loss) performed at a radio frequency distinct from that used to obtain the reference radio fingerprints. The methods and apparatus transform the radio fingerprint, or the reference radio fingerprints, or both, based on that distinction, such as by offsetting signal measurements of the radio fingerprint by an amount determined based on theoretical or experimental models of the dependency of the signal measurements on the radio frequency at which they are performed. The radio fingerprint of the mobile terminal's location may then be compared to the reference radio fingerprints, to accurately estimate the mobile terminal's location despite the radio fingerprint and the reference radio fingerprints having been obtained using different frequencies.
