WiFi-fingerprint based indoor localization map

• US 9,706,366 B2
• Filed: 11/06/2015
• Issued: 07/11/2017
• Est. Priority Date: 11/06/2015
• Status: Active Grant

• Current Assignee: International Business Machines Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: Gu, Yu, Hwang, Inseok, Liu, Su, Wei, Yaoguang
• Primary Examiner(s): Milord, Marceau
• Application Number:
  US14/934,324
• Publication Number:
  US 20170134909A1
• Time in Patent Office: 613 Days
• Field of Search: 4554561, 4554562, 455457, 4554566
• CPC Class Codes: G01S 5/02524 Creating or updating the radio-map
• CPC Class Codes: G01S 5/02525 Gathering the radio frequency fingerprints
• CPC Class Codes: G01S 5/02526 using non-dedicated equipment, e.g. user equipment or crowd-sourcing
• CPC Class Codes: H04B 17/318 Received signal strength
• CPC Class Codes: H04W 16/18 Network planning tools
• CPC Class Codes: H04W 4/029 Location-based management or tracking services
• CPC Class Codes: H04W 4/33 for indoor environments, e.g. buildings
• CPC Class Codes: H04W 64/00 Locating users or terminals or network equipment for network management purposes, e.g. mobility management
• CPC Class Codes: H04W 72/51 based on terminal or device properties
• CPC Class Codes: H04W 84/12 WLAN [Wireless Local Area Networks]

Abstract

Embodiments of the present disclosure relate to making a localization map for a network. A fixed location for a plurality of wireless devices is received and a bisecting line is determined in a plane for each straight line that joins a pair of the plurality of wireless devices. An initial wireless device access sequence is assigned to each of a plurality of regions created on the localization map by the bisecting lines based on the Euclidean distance of the wireless device to the each of the plurality of regions, wherein the wireless device access sequence is the sequence of the wireless devices that provide the strongest to weakest signal to the region. Receiving from a user computing device a received signal strength (RSS) value for each signal received by the user computing device from each of the plurality of wireless devices and updating the localization map based on RSS values.

Claims

1. A method for making a localization map for a network, the method comprising:

receiving, by a computer, a fixed location on a plane for each of a plurality of wireless devices;

for each straight line that joins a pair of the plurality of wireless devices, determining, by the computer, a line in the plane that bisects the joining line at an initial predetermined angle;

assigning, by the computer, an initial wireless device access sequence to each of a plurality of regions created on the localization map by the bisecting lines, based on the Euclidean distance of the wireless device to the each of the plurality of regions, wherein the wireless device access sequence is the sequence of the wireless devices that provide the strongest to weakest signal to the region;

receiving, by the computer, from a user computing device at a known location, a received signal strength (RSS) value for each signal received by the user computing device from each of the plurality of wireless devices; and

updating, by the computer, the localization map based on RSS values, wherein the updating, by the computer, the localization map based on the RSS values, further comprises;

determining, by the computer, which of the bisecting lines on the localization map needs to be updated based on whether the initial wireless device access sequence of the known location accurately reflects the received RSS values at the known location; and

updating, by the computer, the bisecting line on the localization map to reflect the received RSS values.

2. The method of claim 1, wherein the updating, by the computer, the localization map based on the RSS values, further comprises:

transforming, by the computer, the localization map into a dual space map to determine an adjustment for the bisecting line based on the RSS values;

applying, by the computer, the adjustment to the bisecting line on the localization map to update its position.

3. The method of claim 1, further comprising:

determining, by the computer, a position of a user computing device within the localization map.

4. The method of claim 1, wherein the receiving, by the computer, from a user computing device a RSS value for each signal received by the user computing device from each of the plurality of wireless devices further comprises:

establishing, by the computer, a RSS wireless device sequence from strongest to weakest based on the RSS values;

comparing, by the computer, the initial wireless device access sequence and the RSS wireless device sequence for the location of the user computing device; and

determining, by the computer, that the localization map needs to be updated based on the comparison of the RSS wireless device sequence and the initial wireless device sequence.

5. The method of claim 4, wherein the updating, by the computer, the localization map based on the RSS values, further comprises:

determining, by the computer, which of the bisecting lines on the localization map needs to be updated based on whether the initial wireless device access sequence of the known location accurately reflects the received RSS values at the known location; and

updating, by the computer, the bisecting line on the localization map based on the RSS values.

6. The method of claim 5, wherein the updating, by the computer, the localization map based on the RSS values, further comprises:

transforming, by the computer, the localization map into a dual space map to determine an adjustment for the bisecting line based on the RSS values; and

applying, by the computer, the adjustment to the bisecting line on the localization map to update its position.

7. The method of claim 1, wherein the updating of the localization map occurs when detecting the received RSS values at a known location is different from pre-computed sequence or the updating occurs on a predetermined interval.

8. A computer program product for making a localization map for a network, the computer program product comprising:

one or more non-transitory computer-readable storage media and program instructions stored on the one or more non-transitory computer-readable storage media, the program instructions comprising;

receiving a fixed location on a plane for each of a plurality of wireless devices;

for each straight line that joins a pair of the plurality of wireless devices determining a bisecting line in the plane that bisects the joining line at an initial predetermined angle;

assigning an initial wireless device access sequence to each of a plurality of regions created on the localization map by the bisecting lines, based on the Euclidean distance of the wireless device to the each of the plurality of regions, wherein the wireless device access sequence is the sequence of the wireless devices that provide the strongest to weakest signal to the region;

receiving from a user computing device at a known location, a received signal strength (RSS) value for each signal received by the user computing device from each of the plurality of wireless devices; and

updating the localization map based on RSS values, wherein the updating the localization map based on the RSS values, further comprises;

determining which of the bisecting lines on the localization map needs to be updated based on whether the initial wireless device access sequence of the known location accurately reflects the received RSS values at the known location and updating the bisecting line on the localization map based on the RSS values.

9. The computer program product of claim 8, wherein the updating the localization map based on the RSS values, further comprises:

transforming the localization map into a dual space map to determine an adjustment for the bisecting line based on the RSS values;

applying the adjustment to the bisecting line on the localization map to update its position.

10. The computer program product of claim 8, further comprising:

determining a position of a user computing device within the localization map.

11. The computer program product of claim 8, wherein receiving from a user computing device RSS value for each signal received by the user computing device from each of the plurality of wireless devices, further comprises:

establishing a RSS wireless device sequence from strongest to weakest based on the RSS values;

comparing the initial wireless device access sequence and the RSS wireless device sequence for the location of the user computing device; and

determining that the localization map needs to be updated based on the comparison of the RSS wireless device sequence and the initial wireless device sequence.

12. The computer program product of claim 11, wherein the updating the localization map based on the RSS values, further comprises:

determining which of the bisecting lines on the localization map needs to be updated based on whether the initial wireless device access sequence of the known location accurately reflects the received RSS values at the known location; and

updating the bisecting line on the localization map based on the RSS values.

13. The computer program product of claim 12, wherein the updating the localization map based on the RSS values, further comprises:

transforming the localization map into a dual space map to determine an adjustment for the bisecting line on the localization map that needs to be updated based on the RSS values; and

applying the adjustment to the bisecting line on the localization map to update its position.

14. The computer program product of claim 8, wherein the updating of the localization map occurs when detecting the received RSS values at a known location is different from pre-computed sequence or the updating occurs on a predetermined interval.

15. A computer system for making a localization map for a network, the computer system comprising:

one or more computer processors, one or more computer-readable storage media, and program instructions stored on one or more of the computer-readable storage media for execution by at least one of the one or more processors, the program instructions comprising;

receiving a fixed location on a plane for each of a plurality of wireless devices;

for each straight line that joins a pair of the plurality of wireless devices, determining a bisecting line in the plane that bisects the joining line at an initial predetermined angle;

assigning an initial wireless device access sequence to each of a plurality of regions created on the localization map by the bisecting lines, based on the Euclidean distance of the wireless device to the each of the plurality of regions, wherein the wireless device access sequence is the sequence of the wireless devices that provide the strongest to weakest signal to the region;

receiving from a user computing device at a known location, a received signal strength (RSS) value for each signal received by the user computing device from each of the plurality of wireless devices;

establishing a RSS wireless device sequence from strongest to weakest based on the RSS values;

comparing the initial wireless device access sequence and the RSS wireless device sequence for the location of the user computing device; and

determining that the localization map needs to be updated based on the comparison of the RSS wireless device sequence and the initial wireless device sequence;

updating the localization map based on RSS values.

16. The computer system of claim 15, wherein the updating the localization map based on the RSS values, further comprises:

determining which of the bisecting lines on the localization map needs to be updated based on whether the initial wireless device access sequence of the known location accurately reflects the received RSS values at the known location; and

updating the bisecting line on the localization map based on the RSS values.

17. The computer system of claim 16, wherein the updating the localization map based on the RSS values, further comprises:

transforming the localization map into a dual space map to determine an adjustment for the bisecting line on the localization map that needs to be updated based on the RSS values; and

applying the adjustment to the bisecting line on the localization map to update its position.