Centralized route calculation for a multi-hop streetlight network

• US 20090066540A1
• Filed: 09/08/2008
• Published: 03/12/2009
• Est. Priority Date: 09/07/2007
• Status: Active Grant

• Current Assignee: LED Roadway Lighting Ltd.
• Original Assignee: LED Roadway Lighting Ltd.
• Inventors: Varga, Zoltan, Redivo, Marcus, Hamidi, Jam, Marinakis, Dimitri, Lightbody, Simon H.
• Granted Patent: US 8,570,190 B2
• Time in Patent Office: Days
• US Class Current: 340/909
• CPC Class Codes: H05B 47/19 via wireless transmission
• CPC Class Codes: H05B 47/22 with communication between the lamps and a central unit

Abstract

A system and various apparatus and methods performed therein configured for calculating routes touching and monitoring and controlling streetlights includes a multiplicity of streetlight controllers and a local coordinator. Each streetlight controller includes a switch operative to control the operation of a load, a sensor operative to monitor the operation of the load, a processor, and a radio transceiver operative to receive control data and transmit data associated with the streetlight controller. The local coordinator includes a coordinator radio transceiver, and a coordinator processor operative to maintain a list of the multiplicity of streetlight controllers and, cooperatively with the coordinator radio transceiver, exchange messages with any of the multiplicity of streetlight controllers.

Claims

1. A streetlight controller for monitoring and controlling of a streetlight, the streetlight controller comprising:

at least one switch operative to control the operation of a load;

at least one sensor operative to monitor the operation of said load;

at least one processor coupled to said switch and said sensor;

a radio transceiver coupled to said processor and operative to receive data representing a control action associated with said switch and transmit data representing a state of said sensor;

wherein said processor is operative to maintain a list of addresses of, respective, neighbor streetlight controllers and in cooperation with the radio transceiver, transmit the list of addresses to a remote coordination device; and

wherein said radio transceiver is further operative to receive a first broadcast message comprising an address associated with a transmitter that transmitted the first broadcast message and transmit a second broadcast message containing an address of the streetlight controller.

2. The streetlight controller of claim 1 wherein when the first broadcast message is received, the processor is operative to determine whether the address associated with the transmitter is included in the list of addresses and, if not, to add the address associated with the transmitter to the list of addresses.

3. The streetlight controller of claim 2 wherein the processor is operative to add each unique address of streetlight controllers, from which broadcast messages have been satisfactorily received, to the list of addresses.

4. The streetlight controller of claim 3 wherein the processor is operative to assess a quality of each of the broadcast messages to ascertain whether each, respective, broadcast message was satisfactorily received.

5. The streetlight controller of claim 3 wherein the processor is operative to assess an average quality of a plurality of copies of each of the broadcast messages to ascertain whether each, respective, broadcast message is satisfactorily received.

6. The streetlight controller of claim 1 wherein the processor is operative to delay the transmit of the second broadcast message for a random back off time period.

7. The streetlight controller of claim 1 wherein the processor cooperatively with the radio transceiver repeats the transmit of the second broadcast message a predetermined number of times.

8. The streetlight controller of claim 1 wherein the transmit of the second broadcast message is conditioned on whether the first broadcast message includes a new message identification.

9. The streetlight controller of claim 1 wherein the address associated with a transmitter that transmitted the first broadcast message is an address of one of another streetlight controller and the remote coordination device.

10. The streetlight controller of claim 1 wherein the list of addresses is transmitted to the remote coordination device, responsive to receipt of a message requesting the list of addresses.

11. The streetlight controller of claim 1 wherein the transceiver is operative to receive a message addressed to the streetlight controller and the processor is operative to determine, from the message, the route for the message.

12. The streetlight controller of claim 11 wherein the processor in cooperation with the transceiver will forward the message to the next transceiver associated with the next address based on the route for the message, unless a destination for the message is the streetlight controller.

13. A system for monitoring and controlling streetlights, the system comprising:

a multiplicity of streetlight controllers with each streetlight controller further comprising;

at least one switch operative to control the operation of a load,

at least one sensor operative to monitor the operation of said load,

at least one processor coupled to said switch and said sensor, and

a radio transceiver coupled to said processor and operative to receive data representing a control action associated with said each streetlight controller and transmit data associated with said each streetlight controller, and

a local coordinator further comprising;

a coordinator radio transceiver, and

a coordinator processor coupled to the coordinator radio transceiver, the coordinator processor operative to maintain a list of the multiplicity of streetlight controllers and, cooperatively with the coordinator radio transceiver, operative to exchange messages with any of the multiplicity of streetlight controllers.

14. The system of claim 13:

wherein the coordinator processor is further operative to maintain a connectivity model for the list of the multiplicity of streetlight controllers, the connectivity model comprising, for each of the multiplicity of streetlight controllers, a list of addresses of neighbors and, respective, link quality information, and

wherein the coordinator processor is further operative to generate a route from the local coordinator to said each of the multiplicity of streetlight controllers based on the connectivity model.

15. The system of claim 14 wherein the coordinator processor is further operative to adjust the connectivity model to reflect a health parameter for said each of the multiplicity of streetlight controllers, the health parameter used to vary the link quality information for links associated with a corresponding streetlight controller.

16. The system of claim 14 wherein the coordinator processor is further operative to adjust the connectivity model based on a history of message transmission via one or more of said each of the multiplicity of streetlight controllers.

17. The system of claim 16 wherein the coordinator processor is further operative to use exponential averaging to adjust the connectivity model.

18. The system of claim 14 wherein the coordinator processor is further operative to adjust the, respective, link quality information for all links in the connectivity model, thereby allowing new routes to be attempted.

19. The system of claim 13 wherein the coordinator processor is further operative to generate a set of routes from the local coordinator to the multiplicity of streetlight controllers with at least one route touching each of the multiplicity of streetlight controllers.

20. The system of claim 19 wherein a portion of the routes in the set of routes include two or more of the multiplicity of streetlight controllers and the coordinator processor is further operative to indicate in a message for transmission over a route of the portion of routes, which of the two or more of the multiplicity of streetlight controllers should process a payload in the message.

21. A coordinator for a multiplicity of streetlight controllers, which provides routes to the multiplicity of streetlight controllers, the coordinator comprising:

a radio transceiver; and

a processor coupled to the radio transceiver and operative,

to maintain a list of the multiplicity of streetlight controllers,

to generate a route from the local coordinator to each of the multiplicity of streetlight controllers, and

cooperatively with the radio transceiver, to send messages to and receive messages from any of the multiplicity of streetlight controllers.

22. The coordinator of claim 21 wherein the processor is further operative;

to maintain a connectivity model for the list of the multiplicity of streetlight controllers, the connectivity model comprising, for each of the multiplicity of streetlight controllers, a list of addresses of neighbors and, respective, link quality information, and

to generate a route from the coordinator to each of the multiplicity of streetlight controllers based on the connectivity model using a shortest path algorithm.

23. The coordinator of claim 22 wherein the processor cooperatively with the radio transceiver conducts a streetlight controller discovery process pursuant to maintaining the connectivity model, the discovery process further comprising:

transmitting a first broadcast message including an address for the coordinator;

responsive to the transmitting, receiving second broadcast messages, each of the second broadcast messages including an address for a, respective, streetlight controller that transmitted said each of the second broadcast messages, saving each unique address in the second broadcast messages;

transmitting an addressed message to said each unique address, the addressed message requesting a list of neighbor addresses from each streetlight controller associated with said each unique address;

receiving the list of neighbor addresses from said each streetlight controller and identifying new addresses; and

transmitting additional addressed messages to each, respective, new address, receiving a corresponding list of neighbors, and identifying, corresponding new addresses until there are no new addresses.

24. The coordinator of claim 22 wherein the processor is further operative to adjust the connectivity model to reflect a health parameter for said each of the multiplicity of streetlight controllers, the health parameter used to vary the link quality information for links associated with a corresponding streetlight controller.

25. The coordinator of claim 22 wherein the processor is further operative to adjust the connectivity model based on a history of message transmission via one or more of said each of the multiplicity of streetlight controllers.

26. The coordinator of claim 22 wherein the processor is further operative to use exponential averaging to adjust the connectivity model.

27. The coordinator of claim 22 wherein the processor is further operative to adjust the, respective, link quality information for at least a portion of links in the connectivity model, thereby allowing new routes to be attempted.

28. The coordinator of claim 22 wherein, when a message transmission over a route is not acknowledged, the processor is further operative to adjust link quality for one or more links corresponding to that route, thereby generating a second route for that message transmission.

29. A method for providing routes and routing a message to a multiplicity of streetlight controllers, the method comprising:

generating mesh networking routes between the multiplicity of streetlight controllers and a coordinator, at least one route reaching each of the multiplicity of streetlight controllers and a portion of the mesh networking routes comprising intermediate streetlight controllers;

sending messages via the mesh networking routes with one message routed to each of the multiplicity of streetlight controllers; and

receiving the one message routed to each of the multiplicity of streetlight controllers at said each of the multiplicity of streetlight controllers,

wherein for the portion of mesh networking routes, the intermediate streetlight controllers forwarded the message to a subsequent streetlight controller along their, respective, mesh networking route.

30. The method of claim 29 wherein the generating mesh networking routes further comprises conducting a streetlight controller discovery process including sending broadcast messages and collecting a list of neighbors from said each of the multiplicity of streetlight controllers where a collective list of neighbors identifies links between the multiplicity of streetlight controllers to provide a connectivity model having links and corresponding link quality information, wherein a shortest path algorithm is used with the connectivity model for the generating mesh networking routes.

31. The method of claim 30 further comprising maintaining the mesh networking routes using an ongoing learning process that includes dynamically adjusting the mesh networking routes.

32. The method of claim 31 wherein the ongoing learning process further comprises updating the connectivity model with information gained during ongoing communication with at least a portion of the multiplicity of streetlight controllers.

33. The method of claim 31 wherein the maintaining the mesh networking routes further comprises using exponential averaging for adjusting link quality information corresponding to one or more links.

34. The method of claim 31 wherein the maintaining the mesh networking routes further comprises adjusting, in accordance with a health parameter for a given streetlight controller, link quality information for all links with the given streetlight controller.

35. The method of claim 31 wherein the maintaining the mesh networking routes further comprises adjusting the link quality information for all links in the connectivity model, thereby allowing new routes to be attempted.