METHOD AND SYSTEM FOR CONSTRUCTING A DATABASE OF WI-FI BEACON LOCATIONS

1 . A method for constructing a database of Wi-Fi beacon locations, comprising:

(a) storing raw observation data for Wi-Fi beacons in the database of Wi-Fi beacon locations;

(b) generating observation data records for the Wi-Fi beacons according to the raw observation data, and computing a rough location estimate for each Wi-Fi beacon according to the observation data records;

(c) finding outliers of each Wi-Fi beacon from the rough location estimate and the observation data records;

(d) excluding the outliers from the observation data records, and computing final location estimates for the Wi-Fi beacons according to the observation data records which do not include the outliers;

(e) computing inferred-location estimates for the Wi-Fi beacons which do not have a location fix according to the final location estimates; and

(f) storing the inferred-location estimates in the beacon location database.

2 . The method for constructing a database of Wi-Fi beacon locations as claimed in claim 1 , wherein the observation data records include raw location estimates for the Wi-Fi beacons, and each raw location estimate has a location fix.

3 . The method for constructing a database of Wi-Fi beacon locations as claimed in claim 2 , wherein after computing the final location estimates for the Wi-Fi beacons, the method further comprises:

determining whether a ratio of a number of outliers to a number of raw location estimates for a first Wi-Fi beacon is greater than a first threshold;

adding a tag to the first Wi-Fi beacon when determining that the ratio of the first Wi-Fi beacon is greater than the first threshold; and

storing the first Wi-Fi beacon with the tag in a second database comprised in the database of Wi-Fi beacon locations.

4 . The method for constructing a database of Wi-Fi beacon locations as claimed in claim 2 , wherein the rough location estimate for each Wi-Fi beacon is computed according to signal strength measured in the raw location estimates.

5 . The method for constructing a database of Wi-Fi beacon locations as claimed in claim 2 , wherein finding the outliers of each Wi-Fi beacon from the rough location estimate and the observation data records comprises:

assigning a first raw location estimate for a first Wi-Fi beacon whose distance from the rough location estimate for the first Wi-Fi beacon exceeds a second threshold as the outlier.

6 . The method for constructing a database of Wi-Fi beacon locations as claimed in claim 2 , wherein computing the final location estimates further comprises:

examining whether a mobile flag of a first Wi-Fi beacon is set to indicate that the first Wi-Fi beacon is a mobile beacon;

computing the final location estimate for the first Wi-Fi beacon according to signal strengths measured in the raw location estimates for the first Wi-Fi beacon which does not include the outliers when examining the mobile flag of the first Wi-Fi beacon is not set to indicate that the first Wi-Fi beacon is a mobile beacon; and

storing the final location estimate for the first Wi-Fi beacon in a second database, wherein the second database is comprised in the database of Wi-Fi beacon locations.

7 . The method for constructing a database of Wi-Fi beacon locations as claimed in claim 6 , wherein storing the final location estimate for the first Wi-Fi beacon in the second database further comprises:

determining whether the final location estimate for the first Wi-Fi beacon conforms to rules utilized in the second database; and

performing at least one action in response to a determination result,

wherein the rules comprise:

examining whether an original location estimate for the first Wi-Fi beacon has been stored in the second database;

examining whether the mobile flag of the first Wi-Fi beacon is set to indicate that the first Wi-Fi beacon is a mobile beacon;

examining whether the original location estimate for the first Wi-Fi beacon is measured by a user; and

examining whether a distance between the original location estimate and the final location estimate is greater than a third threshold.

8 . The method for constructing a database of Wi-Fi beacon locations as claimed in claim 1 , wherein the inferred-location estimates are stored in a first database comprised in the database of Wi-Fi beacon locations.

9 . The method for constructing a database of Wi-Fi beacon locations as claimed in claim 8 , wherein the first database is a non-relational database.

10 . The method for constructing a database of Wi-Fi beacon locations as claimed in claim 3 , wherein the second database is a relational database system (RDS).

11 . A system for constructing a database of Wi-Fi beacon locations, comprising:

a database of Wi-Fi beacon locations;

a server, coupled to the database of Wi-Fi beacon locations, comprising:

a control circuit;

a processor installed in the control circuit; and

a memory installed in the control circuit and operatively coupled to the processor;

wherein the processor is configured to execute a program code stored in the memory to perform operations comprising:

(a) storing raw observation data for Wi-Fi beacons in the database of Wi-Fi beacon locations;

(b) generating observation data records for the Wi-Fi beacons according to the raw observation data, and computing a rough location estimate for each Wi-Fi beacon according to the observation data records;

(c) finding outliers of each Wi-Fi beacon from the rough location estimate and the observation data records;

(d) excluding the outliers from the observation data records, and computing final location estimates for the Wi-Fi beacons according to the observation data records which do not include the outliers;

(e) computing inferred-location estimates for the Wi-Fi beacons which do not have a location fix according to the final location estimates; and

(f) storing the inferred-location estimates in the beacon location database.

12 . The system for constructing a database of Wi-Fi beacon locations as claimed in claim 11 , wherein the observation data records include raw location estimates for the Wi-Fi beacons, and each raw location estimate has a location fix.

13 . The system for constructing a database of Wi-Fi beacon locations as claimed in claim 12 , wherein after computing the final location estimates for the Wi-Fi beacons, the processor further executes the program code stored in the memory to perform operations comprising:

determining whether a ratio of a number of outliers to a number of raw location estimates for a first Wi-Fi beacon is greater than a first threshold;

adding a tag to the first Wi-Fi beacon when determining that the ratio of the first Wi-Fi beacon is greater than the first threshold; and

storing the first Wi-Fi beacon with the tag in a second database comprised in the database of Wi-Fi beacon locations.

14 . The system for constructing a database of Wi-Fi beacon locations as claimed in claim 12 , wherein the rough location estimate for each Wi-Fi beacon is computed according to signal strength measured in the raw location estimates.

15 . The system for constructing a database of Wi-Fi beacon locations as claimed in claim 12 , wherein finding the outliers of each Wi-Fi beacon from the rough location estimate and the observation data records comprises:

assigning a first raw location estimate for a first Wi-Fi beacon whose distance from the rough location estimate for the first Wi-Fi beacon exceeds a second threshold as the outlier.

16 . The system for constructing a database of Wi-Fi beacon locations as claimed in claim 12 , wherein computing the final location estimates further comprises:

examining whether a mobile flag of a first Wi-Fi beacon is set to indicate that the first Wi-Fi beacon is a mobile beacon;

computing the final location estimate for the first Wi-Fi beacon according to signal strength measured in the raw location estimates for the first Wi-Fi beacon which does not include the outliers when examining the mobile flag of the first Wi-Fi beacon is not set to indicate that the first Wi-Fi beacon is a mobile beacon; and

storing the final location estimate for the first Wi-Fi beacon in a second database, wherein the second database is comprised in the database of Wi-Fi beacon locations.

17 . The system for constructing a database of Wi-Fi beacon locations as claimed in claim 16 , wherein storing the final location estimate for the first Wi-Fi beacon in the second database further comprises:

determining whether the final location estimate for the first Wi-Fi beacon conforms to rules utilized in the second database; and

performing at least one action in response to a determination result,

wherein the rules comprise:

examining whether an original location estimate for the first Wi-Fi beacon has been stored in the second database;

examining whether the mobile flag of the first Wi-Fi beacon is set to indicate that the first Wi-Fi beacon is a mobile beacon;

examining whether the original location estimate for the first Wi-Fi beacon is measured by a user; and

examining whether a distance between the original location estimate and the final location estimate is greater than a third threshold.

18 . The system for constructing a database of Wi-Fi beacon locations as claimed in claim 11 , wherein the inferred-location estimates are stored in a first database comprised in the database of Wi-Fi beacon locations.

19 . The system for constructing a database of Wi-Fi beacon locations as claimed in claim 18 , wherein the first database is a non-relational database.

20 . The system for constructing a database of Wi-Fi beacon locations as claimed in claim 13 , wherein the second database is a relational database system (RDS).