Method and apparatus for on-device positioning using compressed fingerprint archives
View Patent ↗A method and apparatus are provided for on-device positioning using compressed fingerprint archives. The method and apparatus may be configured to provide compression of localization fingerprints, to facilitate efficient on-device positioning based on the RF fingerprint model, and to estimate the physical distance between two or more devices. Embodiments of the method may receive a space-to-access point histogram that corresponds to an access point as observed in a space. A mean, standard deviation, and weight may be calculated and assigned for each of a plurality of access points as observed within a space. The mean, standard deviation, and weight of each access point may be combined to form a data triple. The data triples may be combined to form a fingerprint of access points observed from that space. The data triple or plurality of data triples with the lowest assigned weight(s) may be removed from the fingerprint.
1. A method comprising:
determining the access points of a first fingerprint;
determining the access points of a second fingerprint;
calculating a similarity in signal strengths of access points that are common to both the first fingerprint and the second fingerprint;
determining access points that are exclusive to each of the first fingerprint and the second fingerprint; and
calculating a distance metric between the first fingerprint and the second fingerprint by using the similarity in the signal strengths of access points that are common to the first fingerprint and the second fingerprint to indicate proximate distances, and exclusive access points to indicate distant distances.
2. A method according to claim 1 , wherein the first fingerprint is observed by a first mobile device and wherein the second fingerprint is observed by a second mobile device.
3. A method according to claim 2 , the method further comprising estimating if the first mobile device and the second mobile device are occupying the same space.
4. A method according to claim 2 , the method further comprising assigning permissions to the first mobile device and the second mobile device based upon the distance metric between the first mobile device and the second mobile device.
5. A method according to claim 2 , the method further comprising preventing an exchange of information between the first mobile device and the second mobile device if the distance metric between the first mobile device and the second mobile device exceeds a threshold value.
6. A method according to claim 1 , wherein the first fingerprint is observed by a mobile device and wherein the second fingerprint is observed at a location associated with a virtual message.
7. A method according to claim 6 , the method further comprising:
determining when the distance metric is within a radius of the location associated with the virtual message; and
causing, at least in part, alerting of the mobile device based, at least in part, on the determination.
8. A method according to claim 7 , the method further comprising:
receiving an input for specifying one or more criteria,
wherein the alerting of the mobile device is further based, at least in part, on the one or more criteria.
9. A method according to claim 8 , the method further comprising:
determining a first named location based, at least in part, on the first fingerprint;
determining a second named location based, at least in part, on the second fingerprint;
determining whether the first name location substantially matches the second named location; and
causing, at least in part, alerting of the mobile device based on substantial matching.