NETWORK ARCHITECTURE, RADIO FREQUENCY BASED ASSET TRACKING AND/OR LOCATION ESTIMATION METHODS AND SYSTEMS

• US 20190277939A1
• Filed: 03/07/2019
• Published: 09/12/2019
• Est. Priority Date: 03/09/2018
• Status: Active Grant

• Current Assignee: ABL IP Holding LLC (Acuity Brands, Inc.)
• Original Assignee: ABL IP Holding LLC (Acuity Brands, Inc.)
• Inventors: LI, Xiangrong, GRANT, Jesse, GEORGE, Sajin, MALANDRAKIS, Emanuel Paul, ABOU-RIZK, Mitri J.
• Granted Patent: US 10,502,811 B2
• Time in Patent Office: Days
• CPC Class Codes: G01S 13/878 Combination of several spaced transmitters or receivers of known location for determining the position of a transponder or a reflector G01S13/874 takes precedence
• CPC Class Codes: G01S 5/0081 Transmission between base stations
• CPC Class Codes: G01S 5/02 using radio waves using satellite radio beacon systems for determining position G01S19/00
• CPC Class Codes: G01S 5/0284 Relative positioning
• CPC Class Codes: H04B 17/27 for locating or positioning the transmitter
• CPC Class Codes: H04B 17/318 Received signal strength
• CPC Class Codes: H04W 64/003 locating network equipment
• CPC Class Codes: H04W 84/18 Self-organising networks, e.g. ad-hoc networks or sensor networks
• CPC Class Codes: H04W 88/16 Gateway arrangements

Abstract

Radio frequency-enabled nodes, in an example asset tracking system, receive a basic message including an asset tracking tag identifier from an asset tag. The nodes measure a signal attribute of the received message; and each receiving node transmits a node asset message including the asset tag identifier, a respective node identifier, and the measured signal attribute. Edge gateways each receive one or more node asset messages transmitted by some number of the radio frequency-enabled nodes and rank respective node identifiers based on the measured signal attribute. Each edge gateway forwards an aggregated message to a fog gateway, which parses data from the aggregated messages to form a node identifier tuple identifying at least three nodes near the asset tag. Ordered identifiers from the tuple and known locations of the identified nearby nodes can then be processed to estimate of the location of the asset tag.

Claims

1. A system, comprising:

a number of edge gateways distributed about a space, each edge gateway comprising an edge gateway processor and an edge gateway radio frequency transceiver system, wherein each edge gateway radio frequency transceiver system is configured to communicate via a first frequency band and a second frequency band;

a plurality of radio frequency-enabled nodes distributed about the space, wherein each of the plurality of radio frequency-enabled nodes comprises;

a node processor; and

a node radio frequency transceiver configured to receive and transmit radio frequency signals via the first frequency band; and

a fog gateway comprising a fog gateway radio frequency transceiver and a fog gateway processor, the fog gateway radio frequency transceiver configured to communicate via the second frequency band with each edge gateway radio frequency transceiver system;

wherein each edge gateway;

has a respective radio frequency coverage area within the space, at least with respect to the first frequency band,

is configured by the edge gateway processor to communicate with a plurality of the radio frequency-enabled nodes within the respective radio frequency coverage area via the first frequency band; and

is configured by the edge gateway processor to transmit an aggregated message including an identifier of each of one or more of the radio frequency-enabled nodes within the respective coverage area, based on a node asset message received from each of the one or more radio frequency-enabled nodes within the respective coverage area, each received node asset message comprising;

an identifier of each respective one or more of the radio frequency-enabled nodes,

an identifier of a radio frequency-enabled tag obtained from a radio frequency signal received from the radio frequency-enabled tag by each of the respective one or more radio frequency-enabled nodes within the respective edge gateway'"'"'s coverage area, and

a measured signal attribute of the signal received from the radio frequency-enabled tag by the respective one or more radio frequency-enabled nodes within the respective edge gateway'"'"'s coverage area; and

wherein the fog gateway is configured by the fog gateway processor to;

receive a respective aggregated message from each of a plurality of respective edge gateways; and

parse the received aggregated messages to obtain a node identifier tuple for use in a determination of location of the radio frequency-enabled tag within the space.

2. The system of claim 1, wherein:

the node identifier tuple includes a list of three radio frequency-enabled node identifiers having associated highest signal attribute of signals received from the radio frequency-enabled tag, among all of the radio frequency-enabled nodes having received signals from the radio frequency-enabled tag, and

the three radio frequency-enabled node identifiers are ordered in the list in the tuple according to a ranking of signal attribute of signals received from the radio frequency-enabled tag by the three radio frequency-enabled nodes corresponding to the three radio frequency-enabled node identifiers.

3. The system of claim 2, wherein the node identifier tuple comprises:

a first ordinal representing the node identifier associated with the strongest received signal strength value of received signal strengths measured at three nodes indicated by the three node identifiers,

a second ordinal representing the node identifier associated with an intermediary received signal strength value of received signal strengths measured at the three nodes indicated by the three node identifiers, and

a third ordinal representing the node identifier associated with a lowest received signal strength value of the received signal strengths measured at the three nodes indicated by the three node identifiers.

4. The system of claim 2, wherein the node identifier tuple comprises:

a first ordinal representing the node identifier associated with the lowest received signal strength value of received signal strengths measured at three nodes indicated by the three node identifiers,

a second ordinal representing the node identifier associated with an intermediary received signal strength value received signal strengths measured at the three nodes indicated by the three node identifiers, and

a third ordinal representing the node identifier associated with the strongest received signal strength value of received signal strengths measured at the three nodes indicated by the three node identifiers.

5. The system of claim 2, further comprising a location estimation functionality/application configured to process the three radio frequency-enabled node identifiers as ordered in the list in the tuple to estimate the location of the radio frequency-enabled device within the space.

6. The system of claim 5, wherein the fog gateway is further configured by the fog gateway processor to implement the location estimation functionality/application.

7. The system of claim 6, wherein to implement the location estimation functionality/application, the fog gateway processor is configured to:

obtain specific locations within the space of radio frequency-enabled nodes associated with the node identifiers in the list in the node identifier tuple;

use the specific node locations to identify a polygonal region, wherein the vertices of the polygonal region are the specific node locations of the transmitting node identifiers; and

identify a location within the polygonal region as the estimated location of the radio frequency-enabled device within the space.

8. The system of claim 5, further comprising:

a computing device coupled for communication with the fog gateway, the computing device including a processor and a memory, wherein;

the fog gateway is further configured by the fog gateway processor to forward the node identifier tuple to the computing device; and

the computing device processor is configured to receive and process the node identifier tuple to implement the location estimation functionality/application.

9. The system of claim 8, wherein to implement the location estimation functionality/application, the computing device processor is configured to:

obtain specific locations within the space of radio frequency-enabled nodes associated with the node identifiers in the list in the node identifier tuple;

use the specific node locations to identify a polygonal region, wherein the vertices of the polygonal region are the specific node locations of the transmitting node identifiers; and

identify a location within the polygonal region as the estimated location of the radio frequency-enabled device within the space.

10. The system of claim 1, further comprising:

a plurality of lighting fixtures distributed throughout the space,

wherein each of the respective radio frequency-enabled nodes is in or collocated with a respective lighting fixture of the plurality of lighting fixtures distributed throughout the space.

11. The system of claim 10, wherein each edge gateway is further configured by the respective edge gateway processor to:

transmit via the second frequency band, to the fog gateway, messages containing;

a node identifier update or commissioning information, related to one or more of the radio frequency-enabled nodes;

or an edge gateway location message or an edge gateway status message.

12. The system of claim 10, wherein each edge gateway is further configured by the respective edge gateway processor to:

receive via the second frequency band, from the fog gateway, messages containing information for distribution by the respective edge gateway to one or more of the radio frequency-enabled nodes within the respective radio frequency coverage area of the respective edge gateway,

wherein the information in the received messages includes at least one of a software update, a firmware update, a node identifier update, commissioning information, or a lighting command.

13. The system of claim 10, wherein each edge gateway is in or collocated with a respective lighting fixture of the plurality of lighting fixtures distributed throughout the space.

14. A method, comprising steps of:

receiving, at three or more radio frequency-enabled nodes distributed about a space, a basic message transmitted by an asset tracking tag, the basic message including an identifier of the asset tracking tag and a basic message sequence number;

at each of the three or more radio frequency-enabled nodes, measuring a signal attribute of the received basic message and associating the measured signal attribute with a node identifier of the respective radio frequency-enabled node making the signal attribute measurement;

transmitting, by each of the three or more radio frequency-enabled nodes, a node asset message including the asset tracking tag identifier, the basic message sequence number, the node identifier of the respective one of the three or more radio frequency-enabled nodes transmitting the respective node asset message, and the measured signal attribute of the basic message measured by the respective one of the three or more radio frequency-enabled nodes transmitting the respective node asset message;

at each of two or more edge gateways;

receiving a respective transmitted node asset message transmitted by one or more of the radio frequency-enabled nodes, and in response determining a number of the respective node identifiers of nodes nearest to the asset tracking tag based on the signal attribute of the basic message measured by the one or more nodes; and

forwarding to a fog gateway of the space, an aggregated message including the asset tracking tag identifier, the basic message sequence number, a list of the number of node identifiers in association with respective highest measured signal attribute values, and an identifier of the edge gateway; and

parsing aggregated messages from the two or more edge gateways to remove any duplicate data and obtain a node identifier tuple; and

estimating location of the radio frequency-enabled tag within the space based at least in part on node identifiers in the node identifier tuple.

15. The method of claim 14, wherein:

the node identifier tuple includes a list of three radio frequency-enabled node identifiers having associated highest signal attribute of signals received from the radio frequency-enabled tag, among all of the radio frequency-enabled nodes having received signals from the radio frequency-enabled tag, and

the three radio frequency-enabled node identifiers are ordered in the list in the tuple according to a ranking of signal attribute of signals received from the radio frequency-enabled tag by the three radio frequency-enabled nodes corresponding to the three radio frequency-enabled node identifiers.

16. The method of claim 15, wherein the node identifier tuple comprises:

a first ordinal representing the node identifier associated with the strongest received signal strength value of received signal strengths measured at three nodes indicated by the three node identifiers,

a second ordinal representing the node identifier associated with an intermediary received signal strength value of received signal strengths measured at three nodes indicated by the three node identifiers, and

a third ordinal representing the node identifier associated with a lowest received signal strength value of the received signal strengths measured at three nodes indicated by the three node identifiers.

17. The method of claim 15, wherein the node identifier tuple comprises:

a first ordinal representing the node identifier associated with the lowest received signal strength value of received signal strengths measured at three nodes indicated by the three node identifiers,

a second ordinal representing the node identifier associated with an intermediary received signal strength value received signal strengths measured at three nodes indicated by the three node identifiers, and

a third ordinal representing the node identifier associated with the strongest received signal strength value of received signal strengths measured at three nodes indicated by the three node identifiers.

18. The method of claim 15, wherein the location estimating step comprises:

obtaining specific locations within the space of radio frequency-enabled nodes associated with the node identifiers in the list in the node identifier tuple;

using the specific node locations to identify a polygonal region, wherein the vertices of the polygonal region are the specific node locations of the transmitting node identifiers; and

identifying a location within the polygonal region as the estimated location of the radio frequency-enabled device within the space.