Apparatus and method for establishing data communication in a time-synchronized mesh wireless network during time synchronization failures

• US 8,761,084 B2
• Filed: 01/14/2009
• Issued: 06/24/2014
• Est. Priority Date: 01/14/2009
• Status: Active Grant

• Current Assignee: Vigilent Corporation
• Original Assignee: Synapsense Corporation (Panduit Corporation)
• Inventors: Pandey, Raju, Han, Seokman Paul, Ghosh, Rituparna
• Primary Examiner(s): Russell, Wanda Z
• Application Number:
  US12/321,118
• Publication Number:
  US 20100177708A1
• Time in Patent Office: 1,987 Days
• Field of Search: 370/328, 370/338
• US Class Current: 370/328
• CPC Class Codes: H04W 52/0216 using a pre-established activity schedule, e.g. traffic indication frame
• CPC Class Codes: H04W 56/00 Synchronisation arrangements
• CPC Class Codes: H04W 74/0883 for un-synchronized access
• CPC Class Codes: Y02D 30/70 in wireless communication networks

Abstract

Various embodiments provide an apparatus and method for establishing data communication in a time-synchronized mesh wireless network during time synchronization failures. An example embodiment includes experiencing circumstances adversely affecting synchronization of data communications between wireless network nodes; transitioning to an alert mode wherein a radio of a wireless network node is activated for a longer period of time relative to a normal operating mode; sending a message to at least one neighbor node; listening for a response from the neighbor node; and establishing data communications with the neighbor node upon receiving the response.

Claims

1. A method comprising:

experiencing circumstances adversely affecting time synchronization of data communications between wireless network nodes in a wireless mesh network, the circumstances causing a network node to lose time synchronization with other network nodes;

transitioning to an alert mode wherein a radio of a wireless network node is activated for a longer period of time relative to a normal low power mode, the transitioning to the alert mode being performed when a network node loses time synchronization with other network nodes;

setting the radio of the wireless network node to a pre-defined common radio channel while in the alert mode for communicating with other network nodes;

sending a message to at least one neighbor node;

listening for a response from the neighbor node; and

establishing data communications with the neighbor node upon receiving the response.

2. The method as claimed in claim 1 including listening for a response from the neighbor node on a pre-defined common channel.

3. The method, as claimed in claim 1 wherein the response from the neighbor node includes a status of the neighbor node.

4. The method as claimed in claim 1 wherein the response from the neighbor node includes a temporary local data communications schedule.

5. The method as claimed in claim 1 wherein the message sent to at least one neighbor node is a jamming message causing the neighbor node to transition to the alert mode.

6. The method as claimed in claim 1 wherein the circumstances are a rapid rise in temperature.

7. The method as claimed in claim 1 wherein the circumstances are a clock failure.

8. The method as claimed in claim 1 including tunneling a data path to a neighbor node.

9. The method as claimed in claim 1 wherein all wireless network nodes of the wireless mesh network operate in the alert mode for at least a portion of time.

10. The method as claimed in claim 1 wherein a plurality of wireless network nodes of the wireless mesh network do not operate in the alert mode for at least a portion of time.

11. A wireless network node comprising:

a processor;

a wireless network interface, coupled to the processor, to communicate with other nodes of a wireless network;

a radio for data communications via the wireless network interface; and

processing logic, executable by the processor, to determine if circumstances have adversely affected synchronization of data communications between wireless network nodes, the circumstances causing a network node to lose time synchronization with other network nodes;

transition to an alert mode wherein the radio is activated for a longer period of time relative to a normal operating mode, the processing logic being configured to transition to the alert mode when a network node loses time synchronization with other network nodes;

set the radio of the wireless network node to a pre-defined common radio channel while in the alert mode for communicating with other network nodes;

send a message to at least one neighbor node;

listen for a response from the neighbor node; and

establish data communications with the neighbor node upon receiving the response.

12. The wireless network node as claimed in claim 11 being further configured to listen for a response from the neighbor node on a pre-define common channel.

13. The wireless network node as claimed in claim 11 wherein the response from the neighbor node includes a status of the neighbor node.

14. The wireless network node as claimed in claim 11 wherein the response from the neighbor node includes a temporary local data communications schedule.

15. The wireless network node as claimed in claim 11 wherein the message sent to the at least one neighbor node is a jamming message causing the neighbor node to transition to the alert mode.

16. A wireless network comprising:

a gateway;

a first wireless network node in data communication with the gateway; and

a second wireless network node including processing logic to determine if circumstances have adversely affected synchronization of data communications between wireless network nodes, the circumstances causing a network node to lose time synchronization with other network nodes;

transition to an alert mode wherein a radio of the second wireless network node is activated for a longer period of time relative to a normal operating mode, the processing logic being configured to transition to the alert mode when a network node loses time synchronization with other network nodes;

set the radio of the second wireless network node to a pre-defined common radio channel while in the alert mode for communicating with other network nodes;

send a message to the first wireless network node;

listen for a response from the first wireless network node;

establish data communications with the first wireless network node upon receiving the response; and

send data to the gateway via the first wireless network node.

17. The wireless network as claimed in claim 16 wherein the second wireless network node being further configured to listen for a response from the first wireless network node on a pre-defined common channel.

18. The wireless network as claimed in claim 16 wherein the response from the first wireless network node includes a status of the first wireless network node.

19. The wireless network as claimed in claim 16 wherein the response from the first wireless network node includes a temporary local data communications schedule.

20. The wireless network as claimed in claim 16 wherein the message sent to the first wireless network node is a jamming message causing the first wireless network node to transition to the alert mode.

21. The wireless network as claimed in claim 16 wherein all wireless network nodes of the wireless network operate in the alert mode for at least a portion of time.

22. The wireless network as claimed in claim 16 wherein a plurality of wireless network nodes of the wireless network do not operate in the alert mode for at least a portion of time.

23. An article of manufacture comprising a non-transitory machine-readable storage medium having machine executable instructions embedded thereon, which when executed by a machine, cause the machine to:

determine if circumstances are adversely affecting synchronization of data communications between wireless network nodes, the circumstances causing a network node to lose time synchronization with other network nodes;

transition to an alert mode wherein a radio of a wireless network node is activated for a longer period of time relative to a normal operating mode, the machine executable instructions being configured to transition to the alert mode when a network node loses time synchronization with other network nodes;

set the radio of the wireless network node to a pre-defined common radio channel while in the alert mode for communicating with other network nodes;

send a message to at least one neighbor node;

listen for a response from the neighbor node; and

establish data communications with the neighbor node upon receiving the response.

24. The article of manufacture as claimed in claim 23 being further configured to listen for a response from the neighbor node on a pre-defined common channel.

25. A method comprising:

listening for a message from the neighbor node;

transitioning to an alert mode wherein a radio of a wireless network node is activated far a longer period of time relative to a normal operating mode, the transitioning to the alert mode being performed when a network node loses time synchronization with other network nodes;

setting the radio of the wireless network node to a pre-defined common radio channel while in the alert mode for communication with other network nodes;

sending a message to at least one neighbor node;

listening for a response from the neighbor node; and

establishing data communications with the neighbor node upon receiving the response.

26. The method as claimed in claim 25 including listening for a response from the neighbor node on a pre-defined common channel.

27. The method as claimed in claim 25 including marking a data packet with an alert mode indication.