Systems and methods for determining locations of wireless sensor nodes in an asymmetric network architecture

• US 9,529,076 B2
• Filed: 01/27/2015
• Issued: 12/27/2016
• Est. Priority Date: 01/27/2015
• Status: Active Grant

• Current Assignee: Zainar, Inc.
• Original Assignee: Dragonfly Technology Inc.
• Inventors: Subramanian, Vivek, Alon, Elad, Pavate, Vikram
• Primary Examiner(s): Ajayi, Joel
• Application Number:
  US14/607,050
• Publication Number:
  US 20160216362A1
• Time in Patent Office: 700 Days
• Field of Search: 455/456.5
• US Class Current: 1/1
• CPC Class Codes: G01S 5/0289 of multiple transceivers, e.g. in ad hoc networks
• CPC Class Codes: G01S 5/10 Position of receiver fixed by co-ordinating a plurality of position lines defined by path-difference measurements , e.g. omega or decca systemsG01S5/12 takes precedence ; beacons and receivers cooperating therewith G01S1/306, G01S1/308
• CPC Class Codes: H04W 4/02 Services making use of location information
• CPC Class Codes: H04W 56/001 Synchronization between nodes
• CPC Class Codes: H04W 84/18 Self-organising networks, e.g. ad-hoc networks or sensor networks

Abstract

Systems and methods for determining location information for sensor nodes in a wireless asymmetric network are disclosed herein. In one embodiment, an apparatus (e.g., hub) for providing a wireless asymmetric network architecture includes a memory for storing instructions, one or more processing units to execute instructions to establish and control communications in a wireless asymmetric network architecture, and radio frequency (RF) circuitry including multiple antennas to transmit and receive communications in the wireless asymmetric network architecture. The RF circuitry may include multiple antennas to transmit communications to a plurality of sensor nodes each having a wireless device with a transmitter and a receiver to enable bi-directional communications with the RF circuitry of the apparatus in the wireless asymmetric network architecture. The one or more processing units are configured to execute instructions to determine location information for the plurality of sensor nodes based on receiving communications from each sensor node.

Claims

1. A system for providing a wireless asymmetric network, comprising:

a first hub having one or more processing units and a first antenna for transmitting and receiving communications in the wireless asymmetric network;

a second hub having one or more processing units and a second antenna for transmitting and receiving communications in the wireless asymmetric network; and

a plurality of sensor nodes each having a wireless device with a transmitter and a receiver to enable bi-directional communications with the first and second hubs in the wireless asymmetric network architecture, wherein the one or more processing units of the first and second hubs are configured to execute instructions to receive communications from each sensor node including time of arrival information from each sensor node, to identify shortest direct paths for distances between the plurality of sensor nodes and the first and second hubs in a multi-path environment using the time of arrival information, to synchronize the first and second hubs with each other and share location information of the plurality of sensors nodes, and to triangulate from distances measured via the shortest direct paths to determine location information including location for the plurality of sensor nodes.

2. The system of claim 1, wherein the first hub is powered by a mains electrical source and the plurality of sensor nodes are each powered by a battery source to form the wireless asymmetric network, wherein an asymmetry of available power for the first hub and the plurality of sensor nodes is exploited to enhance battery life and communication range in a wireless sensor network of the plurality of sensor nodes based on low-duty cycle networking to reduce transmission-related energy consumption of the plurality of sensor nodes in the wireless sensor network.

3. The system of claim 1, wherein the location information for each sensor node has a location precision of 3 meters (m) or less with the location precision being designed based on an application of a sensor network that is formed with the plurality of sensor nodes.

4. The system of claim 1, wherein the one or more processing units of the first and second hubs are configured to execute instructions to determine location information for the plurality of sensor nodes based on triangulating from distances measured via strength of signal information that is associated with the received communications.

5. The system of claim 1, wherein the wireless asymmetric network architecture comprises a wireless tree asymmetric network architecture.

6. The system of claim 1, wherein the wireless asymmetric network architecture comprises a wireless tree and mesh asymmetric network architecture.

7. The system of claim 1, wherein the one or more processing units of the second hub are configured to execute instructions to send communications to the first hub and to receive communications from the first hub for controlling and monitoring the wireless asymmetric network architecture.

8. The system of claim 1, wherein the first antenna of the first hub and the second antenna of the second hub to transmit ultra-wide band (UWB) communications to the plurality of sensor nodes and to receive UWB communications from the plurality of sensor nodes.

9. A hub for providing a wireless asymmetric network architecture, comprising:

a memory for storing instructions;

one or more processing units to execute instructions to establish and control communications in the wireless asymmetric network architecture; and

radio frequency (RF) circuitry including multiple antennas to transmit and receive communications in the wireless asymmetric network architecture, the RF circuitry including multiple antennas to transmit communications to a plurality of sensor nodes each having a wireless device with a transmitter and a receiver to enable bi-directional communications with the RF circuitry of the apparatus in the wireless asymmetric network architecture, wherein the one or more processing units are configured to execute instructions to receive on each antenna of the RF circuitry of the hub communications from each sensor node including time of arrival information from each sensor node, to identify the shortest direct paths for distances between the plurality of sensor nodes and the hub in a multi-path environment using the time of arrival information, and to triangulate from distances measured via the shortest direct paths to determine location information including location for the plurality of sensor nodes.

10. The hub of claim 9, wherein the apparatus is powered by a mains electrical source and the plurality of sensor nodes are each powered by a battery source or another energy source to form the wireless asymmetric network.

11. The hub of claim 9, wherein the one or more processing units are configured to execute instructions to determine location information for the plurality of sensor nodes based on at least one of angle of arrival information, signal strength information, and time of arrival information for the communications from the plurality of sensor nodes.

12. The hub of claim 11, wherein the one or more processing units are configured to execute instructions to determine location information for the plurality of sensor nodes based on angle of arrival information for determining an angle of arrival with a strongest signaling component and combined with information to identify a shortest direct path between the apparatus and each sensor node in a multi-path environment, which is determined from time of arrival information, for the communications from the plurality of sensor nodes.

13. The hub of claim 9, wherein the wireless asymmetric network architecture comprises at least one of a wireless tree asymmetric network architecture or a wireless tree and mesh asymmetric network architecture.

14. The hub of claim 9, wherein the multiple antennas of the RF circuitry to transmit ultra-wide band (UWB) communications to the plurality of sensor nodes and to receive UWB communications from the plurality of sensor nodes.

15. A method for determining location in a wireless asymmetric network architecture, comprising:

transmitting, with radio frequency (RF) circuitry including multiple antennas of a hub, communications to a plurality of sensor nodes in the wireless asymmetric network architecture;

receiving, with the RF circuitry including each of the multiple antennas of the hub, communications including time of arrival information from each of the plurality of sensor nodes each having a wireless device with a transmitter and a receiver to enable bi-directional communications with the RF circuitry of the hub in the wireless asymmetric network architecture;

identifying shortest direct paths for distances between the plurality of sensor nodes and the hub in a multi-path environment using the time of arrival information; and

triangulating from distances measured via the shortest direct paths to determine location information including location for the plurality of sensor nodes.

16. The method of claim 15, wherein the hub is powered by a mains electrical source and the plurality of sensor nodes are each powered by a battery source, wherein the location information for each sensor node has a location precision of 1 meter (m) or less such that approximately no overlap occurs in the certainty of position of any two sensor nodes.

17. The method of claim 15, further comprising:

determining, with one or more processing units of the hub, location information for the plurality of sensor nodes based on at least one of angle of arrival information, signal strength information, and time of arrival information for the communications received from the plurality of sensor nodes.

18. The method of claim 17, wherein the one or more processing units are configured to execute instructions to determine location information for the plurality of sensor nodes based on angle of arrival information for determining an angle of arrival with a strongest signaling component and combined with information to identify a shortest direct path in a multi-path environment, which is determined from time of arrival information, for the communications from the plurality of sensor nodes.

19. The method of claim 15, wherein the wireless asymmetric network architecture comprises at least one of a wireless tree asymmetric network architecture or a wireless tree and mesh asymmetric network architecture.

20. The method of claim 15, wherein the multiple antennas of the hub to transmit ultra-wide band (UWB) communications to the plurality of sensor nodes and to receive UWB communications from the plurality of sensor nodes.