SYSTEMS AND METHODS FOR CONTROLLING SLEEP STATES OF NETWORK NODES

• US 20090022078A1
• Filed: 05/02/2008
• Published: 01/22/2009
• Est. Priority Date: 05/02/2007
• Status: Active Grant

• Current Assignee: Synapse Wireless Incorporated (Mcwane Incorporated)
• Original Assignee: Synapse Wireless Incorporated (Mcwane Incorporated)
• Inventors: Martindale, Rick, Patterson, Wade C.
• Granted Patent: US 8,081,590 B2
• Time in Patent Office: Days
• US Class Current: 370/311
• CPC Class Codes: G01D 21/00 Measuring or testing not otherwise provided for
• CPC Class Codes: H04L 67/12 specially adapted for proprietary or special-purpose networking environments, e.g. medical networks, sensor networks, networks in vehicles or remote metering networks

Abstract

The present disclosure generally relates to systems and methods for controlling nodes in a communication network, such as a wireless sensor network. In one exemplary embodiment, a node, referred to herein as a “coordinator node,” controls the operation of various nodes, referred to herein as “sensor nodes,” that are configured to monitor various parameters. The coordinator node from time-to-time broadcasts a beacon to the sensor nodes. The beacon can include various information that is used by the sensor nodes for control. In one exemplary embodiment, the beacon includes node-specific information that informs at least some nodes that they are to transition to a sleep state for a certain period of time. Such nodes, based on the beacon, transition to a sleep state, thereby conserving electrical power.

Claims

1. A wireless sensor network, comprising:

a coordinator node configured to broadcast a beacon; and

a plurality of sensor nodes including at least a first sensor node and a second sensor node, each of the sensor nodes having a sensor for reading a parameter and configured to transmit data based on the sensor over the network, the first sensor node configured to reply to the beacon, wherein a component of the second sensor node is configured to transition to a sleep state based on whether an identifier of the second sensor node is in the beacon.

2. The network of claim 1, wherein the coordinator node is configured make a determination whether the second sensor node is to receive a message during an expected activity relating to the sensor nodes, and wherein the coordinator node is configured to insert the identifier of the second sensor node into the beacon based on the determination.

3. The network of claim 1, wherein the coordinator node is configured to discover a presence of the first sensor node based on a reply transmitted by the second sensor node in response to the beacon.

4. The network of claim 1, wherein the beacon does not identify the first sensor node.

5. The network of claim 1, wherein the beacon includes the identifier and a parameter associated with the identifier, the parameter indicative of a time period, and wherein the second sensor node is configured to control a duration of the sleep state based on the parameter.

6. The network of claim 1, wherein the beacon includes the identifier and a beacon count associated with the identifier, and wherein the second sensor node is configured to control a duration of the sleep state based on the beacon count.

7. The network of claim 1, wherein the beacon has a node locator value, and wherein the first sensor node is configured to reply to the beacon based on the node locator value.

8. The network of claim 7, wherein the first sensor node is configured to perform a comparison between the node locator value and a node locator value in another beacon received by the first sensor node, the first sensor node further configured to transmit a beacon reply to the coordinator node based on the comparison.

9. A method for use in a wireless sensor network, comprising the steps of:

broadcasting a beacon;

receiving the beacon at a plurality of sensor nodes including at least a first sensor node and a second sensor node, each of the sensor nodes having a sensor;

determining whether the beacon has an identifier of the second. sensor node;

replying, via the first sensor node, to the beacon; and

transitioning a component of the second sensor node to a sleep state based on the determining step.

10. The method of claim 9, further comprising the steps of:

determining whether the second sensor node is to receive a message during an expected activity relating to the sensor nodes; and

inserting the identifier of the second sensor node into the beacon based on the determining whether the second sensor node is to receive the message step.

11. The method of claim 9, further comprising the step of discovering a presence of the first sensor node based on the replying step.

12. The method of claim 9, wherein the beacon does not identify the first sensor node.

13. The method of claim 9, further comprising the steps of:

inserting the identifier into the beacon;

associating a parameter with the inserted identifier, the parameter indicative of a time period; and

controlling a duration of the sleep state based on the parameter.

14. The method of claim 9, wherein the beacon has a locator value, and wherein the replying step is based on the locator value.

15. The method of claim 14, further comprising the step of comparing the node locator value to a node locator value in another beacon received by the first sensor node, wherein the replying step is based on the comparing step.

16. A method for use in a wireless sensor network, comprising the steps of:

broadcasting a beacon including identifiers of sensor nodes that are to receive messages within a specified time period; and

transitioning a component of a first sensor node to a sleep state in response to a determination that an identifier of the first sensor node is not included in the beacon.

17. The method of claim 16, further comprising the step of controlling a duration of the sleep state based on an expected time of transmission of a second beacon such that the component is awake at the time of the transmission.

18. The method of claim 16, further comprising the step of transitioning a component of a second sensor node to a sleep state in response to a determination that an identifier of the second sensor node is included in the beacon.

19. The method of claim 18, wherein the identifier of the second sensor node is included in the beacon and associated with a beacon count included in the beacon, and wherein the second sensor node is configured to control a duration of the sleep state for the component of the second sensor node based on the beacon count.