System and method for indoor localization using beacons
Systems and methods are described for determining positions of indoor localization beacons without requiring a physical site survey. In a coarse positioning method, a mobile node receives beacon signals that identify rooms (such as stores in a shopping mall) in which the beacons are located. The mobile node obtains floor plan information relating to the building and estimates beacon locations based on the floor plan and beacon signal strength. The estimated beacon locations may be arranged in a predetermined geometric pattern based on the number of beacons in a room. In a fine positioning method, a mobile node recognizes its proximity to a beacon and responsively measures the distance to other beacons. Estimated beacon positions may be used to estimate the location of the mobile node using trilateration or other techniques.
1. A method, performed by one or more processors, comprising:
receiving, at a mobile node, beacon messages from a plurality of beacon devices, including at least a first beacon message from a first beacon device in a room, the beacon messages including a room identifier and a beacon identifier;
based on the received beacon messages, determining a number of detected beacon devices in the room; and
setting an initial estimated position of the first beacon device in the room, the initial estimated position being determined at least in part by the number of detected beacon devices in the room.
2. The method of claim 1 , wherein the initial estimated first beacon device position is based on a geometric pattern selected based on the number of detected beacon devices in the room.
3. The method of claim 2 , wherein the position of the first beacon device is a selected position within a geometric pattern including a plurality of positions, and wherein the selected position within the geometric pattern is based at least in part on a received signal strength of at least the first beacon message at the mobile node.
4. The method of claim 1 , further comprising refining the initial estimated position based at least in part on received signal strength of the first beacon device.
5. The method of claim 1 , the method further comprising:
calculating a plurality of estimated locations of the mobile node based on beacon signal strengths received from the plurality of beacon devices by the mobile node and based on estimated positions of the plurality of beacon devices, wherein the plurality of beacon devices comprises the first beacon device;
based on the estimated locations, determining an estimated region of movement of the mobile node;
comparing the region of movement to a floor plan of the room including the plurality of beacon devices; and
changing the estimated position of at least one of the beacon devices based on the comparison of the region of movement to the floor plan.
6. The method of claim 5 , wherein determining an estimated region of movement of the mobile node includes determining the smallest convex polygon that includes all calculated mobile node estimated locations.
7. The method of claim 5 , wherein changing the estimated position of at least one of the beacon devices includes repositioning a centroid of at least one of the beacon devices.
8. The method of claim 5 , wherein the room is in a place of business, the method further comprising determining whether the mobile node is associated with an employee of the place of business, wherein the changing of the estimated positions of the beacon devices is performed only after a determination that the mobile node is associated with an employee.
9. The method of claim 8 , wherein the determination of whether the mobile node is associated with an employee includes determining whether at least some of the estimated locations of the mobile node are in an employee-only area.
10. The method of claim 8 , wherein the determination of whether the mobile node is associated with an employee includes determining whether the mobile node is located in the place of business during an employee-only period.
11. The method of claim 5 , wherein changing the estimated position of at least one of the beacon devices is performed using a partial centroid repositioning method.
12. The method of claim 5 , wherein changing the estimated position of at least one of the beacon devices is performed using a total centroid repositioning method.
13. The method of claim 5 , the method further comprising:
using a camera to determine a plurality of positions of at least one individual in the room;
obtaining a plurality of distance measurements between a mobile node associated with the at least one individual and a beacon device in the plurality of beacon devices; the distance measurements being based at least in part on receive signal strength of beacon signals received by the mobile device from the beacon device; and
wherein changing the estimated position of at least one of the beacon devices is further based at least in part on the determined positions of the at least one individual and on the plurality of distance measurements.
14. A method, performed by one or more processors, comprising:
obtaining floor plan information of a building, wherein the floor plan information identifies locations of a plurality of rooms including a first room;
receiving, at a mobile node, a plurality of beacon signals from a respective plurality of beacon devices;
calculating a plurality of estimated locations of the mobile node based on beacon signal strengths received from the plurality of beacon devices by the mobile node and based on estimated positions of the plurality of beacon devices;
based on the plurality of estimated locations of the mobile node, determining an estimated region of movement of the mobile node;
comparing the region of movement to the floor plan information of the first room including the plurality of beacon devices; and
changing the estimated position of at least one of the beacon devices based on the comparison of the region of movement to the floor plan information.
15. The method of claim 14 ,
wherein the first room is in a place of business, the method further comprising determining whether the mobile node is associated with an employee of the place of business,
wherein the changing of the estimated of at least one of the beacon devices is performed only after a determination that the mobile node is associated with an employee.
16. The method of claim 15 , wherein the determination of whether the mobile node is associated with an employee includes determining whether at least some of the estimated locations of the mobile node are in an employee-only area.
17. The method of claim 15 , wherein the determination of whether the mobile node is associated with an employee includes determining whether the mobile node is located in the place of business during an employee-only period.
18. The method of claim 14 , wherein changing the estimated position of at least one of the beacon devices is performed using a partial centroid repositioning method.
19. A method of determining a beacon location, performed by one or more processors, the method comprising:
receiving, at a mobile node, a first beacon signal from a first beacon device and a second beacon signal from a second beacon device;
based on a first received signal strength of the first beacon signal, determining whether the mobile node is proximate to the first beacon device;
based on a second received signal strength of the second beacon signal, determining a distance from the mobile node to the second beacon device; and
in response to a determination that the mobile node is proximate to the first beacon device, updating an estimated position of at least one of the first beacon device and the second beacon device using the determined distance as a distance measure between the first and second beacon devices.
20. A method comprising:
obtaining floor plan information of a building identifying: (i) locations of a plurality of rooms including a first room, and (ii) locations of a plurality of areas within one or more of the plurality of rooms including at least a first area within the first room;
receiving, at a mobile node, beacon messages from a plurality of beacon devices, including at least a first beacon message from a first beacon device in the first room, the beacon messages including a room identifier and a beacon device identifier;
determining a number of detected beacon devices in the first room based on the received beacon messages;
determining a number of detected beacon devices in the first area of the first room; and
setting an initial estimated position of the first beacon device in the first area of the first room, the initial estimated position being determined at least in part by the number of detected beacon devices in the first room.