Systems and methods for distributed group formation and maintenance in geographically based networks

• US 20050055417A1
• Filed: 09/05/2003
• Published: 03/10/2005
• Est. Priority Date: 09/05/2003
• Status: Active Grant

• Current Assignee: Palo Alto Research Center, Inc. (Xerox Holdings Corp.)
• Original Assignee: Xerox Corporation (Xerox Holdings Corp.)
• Inventors: Liu, Juan, Liu, Jie, Reich, James E.
• Granted Patent: US 7,562,123 B2
• Time in Patent Office: Days
• US Class Current: 709/208
• CPC Class Codes: H04L 67/10 in which an application is distributed across nodes in the network software deployment G06F8/60; multiprogramming arrangements G06F9/46
• CPC Class Codes: H04L 67/125 involving control of end-device applications over a network
• CPC Class Codes: H04L 69/329 in the application layer [OSI layer 7]
• CPC Class Codes: H04L 9/40 Network security protocols
• CPC Class Codes: H04W 4/38 for collecting sensor information
• CPC Class Codes: H04W 64/00 Locating users or terminals or network equipment for network management purposes, e.g. mobility management
• CPC Class Codes: H04W 84/20 Master-slave selection or change arrangements
• CPC Class Codes: Y04S 40/18 Network protocols supporting networked applications, e.g. including control of end-device applications over a network

Abstract

In a distributed sensor network, one or more devices, for example, forming a collaborative group, are associated with a physical phenomenon based on geographical proximity. The sensor network is capable of detecting new phenomena and changing the membership of the collaborative group as the phenomenon changes. Sensors not associated with a detected phenomenon are available to detect new phenomenon, and one group may exist per phenomenon. Upon detection of a phenomenon, a group of nodes is formed and a leader node is elected. As the phenomenon changes over time, new devices come into proximity of the phenomenon and are prevented from forming independent groups associated with the phenomenon. This accomplished in a decentralized way with communication restricted to local neighbors. In a tracking sensor network using a relatively small number of sensors, the sensors are active and maintain a coherent belief associating their measurements with a single common vehicle.

Claims

1. A method of using sensor networks to detect a phenomenon, comprising:

establishing a collaborative group of sensors in a sensor network when a phenomenon is detected;

electing a leader sensor node;

changing the membership of the collaborative group as the phenomenon changes over time; and

suppressing the creation of a new collaborative group as a new sensor detects the phenomenon.

2. The method of claim 1, further comprising sending information packets to sensor nodes within an association region of the phenomenon to associate them with the phenomenon;

and

suppressing nodes in the association region from detecting similar phenomenon.

3. The method of claim 1, further comprising estimating of the state of the phenomenon by the leader node.

4. The method of claim 1, further comprising redefining the collaborative group constituency.

5. The method of claim 1, further comprising selecting a new leader.

6. A sensor network system used to detect a phenomenon, comprising:

a plurality of sensors in a sensor network;

at least one (“

leader”

) processor that establishes membership of one or more sensor nodes in a collaborative group when a phenomenon is detected by at least one of the sensor nodes;

a leader sensor node election scheme that establishes a leader node for the collaborative group;

a collaborative group membership assignment scheme that changes membership of the collaborative group as the phenomenon changes over time; and

collaborative group creation suppression scheme that suppresses the creation of new collaborative groups as new sensor nodes detect the same phenomenon.

7. The sensor network system of claim 6, further comprising, a sender that sends information packets to sensor nodes within an association region of the phenomenon to associate them with the phenomenon;

and

a node suppression scheme that suppresses nodes in the association region from detecting similar phenomena.

8. The sensor system of claim 6, further comprising an estimator that estimates the state of the phenomenon by the leader node.

9. The sensor network system of claim 6, further comprising a redefiner that estimates the collaborative group constituency.

10. The sensor network system of claim 6 further comprising a selector that selects a new leader.