Sensor Net Management Method

• US 20090210075A1
• Filed: 02/23/2005
• Published: 08/20/2009
• Est. Priority Date: 02/23/2005
• Status: Active Grant

• Current Assignee: Maxell, Ltd.
• Original Assignee: Hitachi, Ltd.
• Inventors: Moriwaki, Norihiko
• Granted Patent: US 7,904,052 B2
• Time in Patent Office: Days
• US Class Current: 700/28
• CPC Class Codes: H04L 41/0654 using network fault recovery ring fault isolation or reconfiguration in loop networks without recovery actions by a network management system H04L12/437
• CPC Class Codes: H04L 41/0893 Assignment of logical groups to network elements
• CPC Class Codes: H04L 41/0894 Policy-based network configuration management
• CPC Class Codes: H04L 43/0817 by checking functioning
• CPC Class Codes: H04L 43/12 Network monitoring probes

Abstract

There is provided a sensor node management method in which a user is unconscious of a service break even when a sensor node has failed among a plurality of sensor nodes assuming intermittent operation. Moreover, it is possible to provide a flexible sensor node management method capable of freely modifying the observation grading (space, time) in accordance with a user'"'"'s desire. A base station (30) for containing a plurality of intermittently operating sensor nodes includes a sensor management table (4) for managing the sensor nodes, a group management table (5) for grouping a plurality of sensor nodes, and an operation timing control unit (3). The operation timing control unit (3) decides the operation interval and the relationship for starting each of the sensor nodes. Moreover, the base station and the sensor node have a counter value as a reference of the sensor node operation interval and the operation start phase, which are periodically synchronized.

Claims

1. A base station for receiving data intermittently sent from multiple sensor nodes, comprising:

a memory for storing a sensor management table used to manage the multiple sensor nodes and a group management table used to make the multiple sensor nodes into groups;

a counter value generating circuit which is synchronized with a counter value generating circuit of each of the sensor nodes; and

an operation timing control unit,

wherein the operation timing control unit determines, based on an operation interval of each of the groups that include the multiple sensor nodes, an operation interval of each of the multiple sensor nodes included in the group and phase timing of activation of each of the multiple sensor nodes, and notifies the operation interval and the phase timing of activation, which are managed using a counter value generated by the counter value generating circuit, to the multiple sensor nodes.

2. The base station according to claim 1, wherein the operation timing control unit rearranges, when the number of the sensor nodes included in a group of the groups is changed, the operation interval of each of the multiple sensor nodes included in the group and the phase timing of activation of each of the multiple sensor nodes, and notifies the operation interval and the phase timing of activation to each of the multiple sensor nodes included in the group.

3. The base station according to claim 1, wherein:

the group management table stores, for each group of the groups which have been generated by making the multiple sensor nodes into the groups, the number of the sensor nodes belonging to the group and the operation interval of the group; and

the sensor management table stores, for each sensor node, the operation interval and the phase timing of activation.

4. The base station according to claim 1, wherein sensor data received from sensor nodes which belong to the same group is outputted as sensor data on an identical observation object.

5. The base station according to claim 1, wherein the operation timing control unit modifies, when a spatial granularity for observation is changed, the group configuration of the sensor nodes according to the changed spatial granularity for observation, and modifies the operation interval of each of the multiple sensor nodes included in a modified group and the phase timing of activation of each of the multiple sensor nodes based on the operation interval of the modified group, and notifies the operation interval and the phase timing of activation to each of the multiple sensor nodes.

6. The base station according to claim 1, wherein the operation timing control unit modifies, when a temporal granularity for observation is changed, the operation interval of the groups of the sensor nodes according to the changed temporal granularity for observation, and modifies the operation interval of each of the multiple sensor nodes included in a modified group and the phase timing of activation of each of the multiple sensor nodes based on the operation interval of the modified group, and notifies the operation interval and the phase timing of activation to each of the multiple sensor nodes.

7. The base station according to claim 5, further comprising a data change detecting unit, wherein:

the memory stores an observation granularity modification policy which stores an observation granularity and a condition for modifying an observation granularity; and

the operation timing control unit determines a grouping method according to the observation granularity modification policy, depending on the amount of change in sensing data sent from the sensor nodes, detected by the data change detecting unit, determines the operation interval of each of the multiple sensor nodes included in each of the groups and the phase timing of activation of each of the multiple sensor nodes, and notifies the operation interval and the phase timing of activation to each of the multiple sensor nodes.

17. The base station according to claim 6, further comprising a data change detecting unit, wherein:

the memory stores an observation granularity modification policy which stores an observation granularity and a condition for modifying an observation granularity; and

the operation timing control unit determines a grouping method according to the observation granularity modification policy, depending on the amount of change in sensing data sent from the sensor nodes, detected by the data change detecting unit, determines the operation interval of each of the multiple sensor nodes included in each of the groups and the phase timing of activation of each of the multiple sensor nodes, and notifies the operation interval and the phase timing of activation to each of the multiple sensor nodes.

8. A sensor network management method of managing a sensor network which includes multiple sensor nodes that can be connected to a base station, comprising the steps of:

grouping at least a part of the multiple sensor nodes;

setting, based on an operation interval set for a group that includes the at least a part of the multiple sensor nodes, an operation interval and activation timing, for each of the multiple sensor nodes included in the group;

notifying the set operation interval and activation timing to each of the multiple sensor nodes included in the group; and

collecting sensor data sent from each of the multiple sensor nodes included in the group based on the notified operation interval and activation timing.

9. The sensor network management method according to claim 8, further comprising the steps of:

detecting a change in the number of the multiple sensor nodes included in a group;

rearranging the operation interval of each of the multiple sensor nodes included in the group, in which the number of the multiple sensor nodes has been changed, and phase timing of activation of each of the multiple sensor nodes; and

notifying results of the rearrangement to each of the multiple sensor nodes included in the group.

10. The sensor network management method according to claim 8, further comprising:

storing, for each group, which has been generated by grouping at least a part of the multiple sensor nodes, the number of the sensor nodes belonging to the group and the operation interval of the group in a group management table; and

storing, for each sensor node, the operation interval and the phase timing of activation in the sensor management table.

11. The sensor network management method according to claim 8, further comprising the step of outputting sensor data received from sensor nodes which belong to the same group, as sensor data on an identical observation object.

12. The sensor network management method according to claim 8, further comprising the steps of:

accepting an input for changing a spatial granularity for observation performed by the sensor network;

modifying the group configuration of the sensor nodes according to the changed spatial granularity for observation;

modifying the operation interval of each of the multiple sensor nodes included in the modified group and the phase timing of activation of each of the multiple sensor nodes, based on the operation interval of the modified group; and

notifying results of the modification to each of the multiple sensor nodes.

13. The sensor network management method according to claim 8, further comprising the steps of:

accepting an input for changing a temporal granularity for observation performed by the sensor network;

modifying the operation interval of the groups of the sensor nodes according to the changed temporal granularity for observation;

modifying the operation interval of each of the multiple sensor nodes included in the modified group and the phase timing of activation of each of the multiple sensor nodes, based on the operation interval of the modified group; and

notifying results of the modification to each of the multiple sensor nodes.

14. The sensor network management method according to claim 12, further comprising:

storing in advance an observation granularity modification policy which stores an observation granularity and a condition for modifying an observation granularity by the sensor network;

detecting the amount of change in sensing data sent from the multiple sensor nodes;

determining a grouping method according to the observation granularity modification policy, depending on the detected amount of change in sensing data; and

determining the operation interval of each of the multiple sensor nodes included in each group and the phase timing of activation of each of the multiple sensor nodes, according to the determined grouping method, and notifying the operation interval and the phase timing of activation to each of the multiple sensor nodes.

18. The sensor network management method according to claim 13, further comprising:

storing in advance an observation granularity modification policy which stores an observation granularity and a condition for modifying an observation granularity by the sensor network;

detecting the amount of change in sensing data sent from the multiple sensor nodes;

determining a grouping method according to the observation granularity modification policy, depending on the detected amount of change in sensing data; and

determining the operation interval of each of the multiple sensor nodes included in each group and the phase timing of activation of each of the multiple sensor nodes, according to the determined grouping method, and notifying the operation interval and the phase timing of activation to each of the multiple sensor nodes.

15. A sensor node apparatus for comprising a sensor network which includes multiple sensor node apparatuses capable of being connected to a base station, comprising:

a sensor unit for performing observation;

a communication unit for sending sensor data serving as a result of the observation to the base station;

a counter unit which is synchronized with a counter unit of the base station; and

a controller,

wherein the controller performs control such that a counter value of the counter unit is used to perform activation at observation timing determined based on an observation interval and start timing which are notified by the base station, observation is performed using the sensor unit, and sensor data, serving as a result of the observation, is sent from the communication unit to the base station.

16. The sensor node device according to claim 15, wherein the multiple sensor node devices are grouped based on location information on each of the multiple sensor node devices and based on a requested observation granularity, and the observation interval and the start timing are determined based on a requested observation interval for each group and the number of sensor node devices included in each group.