Location estimation within a wireless mesh network utilizing wireless signal signatures

• US 9,510,149 B2
• Filed: 04/08/2015
• Issued: 11/29/2016
• Est. Priority Date: 04/08/2015
• Status: Active Grant

• Current Assignee: Hitachi Energy Limited
• Original Assignee: ABB Technology AG (ABB Limited)
• Inventors: Pignolet, Yvonne Anne, Kiskani, Mohsen Karimzadeh, Chari, Amalavoyal, Dabirmoghaddam, Ali
• Primary Examiner(s): MAPA, MICHAEL Y
• Application Number:
  US14/681,341
• Publication Number:
  US 20160302035A1
• Time in Patent Office: 601 Days
• Field of Search: 455/67.11, 455/444, 455/446, 4554561-457
• US Class Current: 1/1
• CPC Class Codes: H04W 4/023 using mutual or relative location information between multiple location based services [LBS] targets or of distance thresholds
• CPC Class Codes: H04W 4/029 Location-based management or tracking services

Abstract

Systems, methods and apparatuses for estimating a location within an area are disclosed. One method includes determining a plurality of wireless signal signatures at a plurality of locations within the area, wherein each wireless signal signatures includes a characteristic of a plurality of wireless links between a device and a plurality of network access points at a one of the plurality of locations, wherein the plurality of wireless signal signatures are received by a network manager server. Further, the network manager server receives a present wireless signal signature of a current device. The method further includes estimating locations the current device, including comparing a present wireless signal signature of the current device with plurality of wireless signal signatures, and adaptively re-determining the plurality of wireless signal signatures based on at least one condition of a distributed wireless network that includes the plurality of network access points.

Claims

1. A method of estimating a location within an area, comprising:

determining a plurality of wireless signal signatures at a plurality of locations within the area, wherein each wireless signal signatures includes a characteristic of a plurality of wireless links between a device and a plurality of network access points at a one of the plurality of locations, wherein the characteristic includes a difference between a measured characteristic of the device and an average characteristic between the device and the plurality of network access points at the plurality of locations;

receiving, by a network manager server, the plurality of wireless signal signatures;

receiving, by the network manager server, a present wireless signal signature of a current device;

estimating locations of the current device, comprising comparing a present wireless signal signature of the current device with the plurality of wireless signal signatures; and

adaptively re-determining the plurality of wireless signal signatures based on at least one condition of a distributed wireless network that includes the plurality of network access points.

2. The method of claim 1, wherein the device is a one of the plurality network access points, and further comprising each of the plurality of network access points determining a plurality of wireless signal signatures at a corresponding fixed location within the area.

3. The method of claim 1, wherein the network access points determine the plurality of wireless signal signatures based on upstream communication from at least one of a plurality of current devices.

4. The method of claim 1, wherein each wireless signal signature includes an identifier of each of the plurality of network access points and a characteristic of a wireless signal received through a corresponding one of the plurality of wireless links between the device and the plurality of network access points.

5. The method of claim 1, wherein each signature includes N measured signatures averaged over time.

6. The method of claim 1, further comprising tracking estimated locations of at least one of a plurality of current devices over time.

7. The method of claim 6, further comprising aiding the location estimation based on projected locations of each of the plurality of current devices, wherein the projection is based on the tracked estimated location of each of the plurality of current devices.

8. The method of claim 7, further comprising determining whether to re-determine the plurality of wireless signal signatures at the plurality of locations within the area based on the present wireless signal signature of each of the plurality of current devices and the tracking of the estimated locations of each of the plurality of current devices over time.

9. The method of claim 1, wherein the plurality of network access points monitor wireless signal transmission between each other, and further comprising determining whether to re-determine the plurality of wireless signal signatures at the plurality of locations within the area based on determined variations in the wireless signal transmission between the plurality of network access points.

10. The method of claim 1, wherein comparing a present wireless signal signature of the current device with plurality of wireless signal signatures comprises comparing the present wireless signal signatures of the current device based on an ordering of an identifier of the plurality of network access points, wherein the ordering is based on a received signal characteristic of each of the plurality of network access points.

11. The method of claim 1, wherein the plurality of wireless signal signatures at the plurality of locations includes an identifier and a received signal characteristic of at least a portion of the plurality of network access points.

12. The method of claim 1, wherein the distributed wireless network form a wireless mesh network, and the at least one condition comprises at least one of the plurality of network access points selecting a new routing path through the wireless mesh network.

13. The method of claim 1, wherein aiding the location estimation includes refining a search space of the plurality of wireless signal signatures based on at least one signal characteristic of present communication between at least one of a plurality of current devices and at least one network access point.

14. A network manager server of a wireless network, the network manager server operative to:

receive a plurality of wireless signal signatures at a plurality of locations within the area, wherein each wireless signal signatures includes a characteristic of a plurality of wireless links between a device and a plurality of network access points at a one of the plurality of locations, wherein the characteristic includes a difference between a measured characteristic of the device and an average characteristic between the device and the plurality of network access points at the plurality of locations;

receive a present wireless signal signature of a current device;

estimate locations of the current device, comprising comparing a present wireless signal signature of the current device with the plurality of wireless signal signatures; and

adaptively re-determine the plurality of wireless signal signatures based on at least one condition of a distributed wireless network that includes the plurality of network access points.

15. The network manager server of claim 14, wherein the network manager server is further operative to:

track estimated locations of at least one of the plurality of current devices over time;

aid the location estimation based on projected locations of each of the plurality of current devices, wherein the projection is based on the tracked estimated location of each of the plurality of current devices; and

determine whether to re-determine the plurality of wireless signal signatures at the plurality of locations within the area based on the present wireless signal signature of each of the plurality of current devices and the tracking of the estimated locations of each of the plurality of current devices over time.

16. The network manager server of claim 14, wherein comparing the present wireless signal signature of each of the plurality of current devices with plurality of wireless signal signatures comprises comparing the present wireless signal signatures of each of the plurality of current devices based on an ordering of an identifier of the plurality of network access points, wherein the ordering is based on a received signal characteristic of each of the plurality of network access points.

17. A wireless mesh network, comprising:

a plurality of wireless mesh network gateways, each gateway connected to an upstream network;

a plurality of wireless access nodes, each access node wirelessly connected directly to at least one of the plurality wireless mesh network gateways, or indirectly connected to at least one of the plurality wireless mesh network gateways through one or more upstream wireless access node;

network manager server connected to the wireless mesh network, the network manager server operative to;

receive a plurality of wireless signal signatures at a plurality of locations within the area, wherein each wireless signal signatures includes a characteristic of a plurality of wireless links between a device and a plurality of network access points at a one of the plurality of locations, wherein the characteristic includes a difference between a measured characteristic of the device and an average characteristic between the device and the plurality of network access points at the plurality of locations;

receive a present wireless signal signature of a current device;

estimate locations of the current device, comprising comparing a present wireless signal signature of the current device with plurality of wireless signal signatures; and

adaptively re-determine the plurality of wireless signal signatures based on at least one condition of a distributed wireless network that includes the plurality of network access points.

18. The wireless mesh network of claim 17, wherein the network manager server is further operative to:

track estimated locations of at least one of the plurality of current devices over time;

aid the location estimation based on projected locations of each of the plurality of current devices, wherein the projection is based on the tracked estimated location of each of the plurality of current devices; and

determine whether to re-determine the plurality of wireless signal signatures at the plurality of locations within the area based on the present wireless signal signature of each of the plurality of current devices and the tracking of the estimated locations of each of the plurality of current devices over time.

19. The wireless mesh network of claim 17, wherein the plurality of network access points monitor wireless signal transmission between each other, and further comprising determining whether to re-determine the plurality of wireless signal signatures at the plurality of locations within the area based on determined variations in the wireless signal transmission between the plurality of network access points.

20. The wireless mesh network of claim 17, wherein comparing the present wireless signal signature of each of the plurality of current devices with plurality of wireless signal signatures comprises comparing the present wireless signal signatures of each of the plurality of current devices based on an ordering of an identifier of the plurality of network access points, wherein the ordering is based on a received signal characteristic of each of the plurality of network access points.