METHOD AND SYSTEM FOR NETWORK SETUP AND MAINTENANCE AND MEDIUM ACCESS CONTROL FOR A WIRELESS SENSOR NETWORK

• US 20100039933A1
• Filed: 10/27/2008
• Published: 02/18/2010
• Est. Priority Date: 08/12/2008
• Status: Active Grant

• Current Assignee: General Atomics, Inc.
• Original Assignee: General Atomics, Inc.
• Inventors: Taylor, James Laurence, Askar, Naiel K., Perry, Michael D., Racherla, Venkatagopal, Furuno, David S., Jeyaseelan, Jaya L.
• Granted Patent: US 8,199,635 B2
• Time in Patent Office: Days
• US Class Current: 370/217
• CPC Class Codes: H04L 67/025 for remote control or remote monitoring of applications
• 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
• CPC Class Codes: H04W 40/24 Connectivity information management, e.g. connectivity discovery or connectivity update
• CPC Class Codes: H04W 84/18 Self-organising networks, e.g. ad-hoc networks or sensor networks

Abstract

A sensor network having a first command center and a first access node, comprising a wireless transceiver, coupled to the command center. The sensor network may also include a plurality of nodes individually comprising a wireless transceiver and a directional antenna, wherein each of the plurality of nodes is successively located in a downlink direction relative to the first access node, and is configured to wirelessly communicate via the directional antenna with at least one node of a first neighbor group in a first direction and at least one node of a second neighbor group in a second direction. In addition, a sensor device is individually coupled to at least one of the nodes, and is configured to provide sensor data for the first command center.

Claims

1. A sensor network comprising:

a first command center;

a first access node coupled to the command center and comprising a wireless transceiver;

a plurality of nodes individually comprising a wireless transceiver and a directional antenna, wherein each of the plurality of nodes is successively located in a downlink direction relative to the first access node, and is configured to wirelessly communicate via the directional antenna with at least one node of a first neighbor group in a first direction and at least one node of a second neighbor group in a second direction; and

a sensor device individually coupled to at least one of the plurality of nodes and configured to provide sensor data for the first command center.

2. The sensor network of claim 1, wherein the first neighbor group comprises one node of the plurality of nodes and the second neighbor group comprises one node of the plurality of nodes.

3. The sensor network of claim 1, wherein the first neighbor group comprises two nodes of the plurality of nodes and the second neighbor group comprises two nodes of the plurality of nodes.

4. The sensor network of claim 3, wherein the plurality of nodes are positioned so that each node of the plurality of nodes wirelessly communicate with only the two nodes in the first neighbor group and the two nodes in the second neighbor group.

5. The sensor network of claim 3, wherein each node of the plurality of nodes wirelessly communicate directly with only the two nodes in the first neighbor group and the two nodes in the second neighbor group.

6. The sensor network of claim 1, for each given node of the plurality of nodes, the first neighbor group of the given node comprises two nodes of the plurality of nodes and which are located in an uplink direction relative to the given node, and the second neighbor group of the given node comprises two nodes of the plurality of nodes and which are located in the downlink direction relative to the given node.

7. The sensor network of claim 6, wherein each node of the plurality of nodes is configured to communicate sensor data provided by a non-adjacent downlink node, of the two nodes located in the downlink direction, to a non-adjacent uplink node of the two nodes located in the uplink direction.

8. The sensor network of claim 6, wherein each node of the plurality of nodes is configured to selectively communicate sensor data provided by a non-adjacent downlink node, of the two nodes located in the downlink direction, to either a non-adjacent uplink node or an adjacent uplink node of the two nodes located in the uplink direction based upon operation criteria.

9. The sensor network of claim 8, wherein the operation criteria identifies that the non-adjacent uplink node is a failed node, thus permitting the communicating of the sensor data to the adjacent uplink node.

10. The sensor network of claim 6, wherein each node of the plurality of nodes is configured to selectively receive sensor data provided by either a non-adjacent downlink node or an adjacent downlink node of the two nodes located in the downlink direction based upon operation criteria.

11. The sensor network of claim 10, wherein the operation criteria identifies that the non-adjacent downlink node is a failed node, thus permitting the receiving of the sensor data from the adjacent downlink node of the plurality of nodes.

12. The sensor network of claim 1, wherein each node of the plurality of nodes that include the sensor device is configured to communicate the sensor data to the first command center via an uplink communication in the first direction with a node of the first neighbor group.

13. The sensor network of claim 1, wherein each node of the plurality of nodes is configured to receive sensor data provided by a downlink node of the second neighbor group, and is further configured to communicate the sensor data to an uplink node of the first neighbor group.

14. The sensor network of claim 13, wherein the received sensor data provided by the downlink node is generated by a sensor device coupled to a node located in the first direction from the at least one node of the second neighbor group.

15. The sensor network of claim 1, wherein the directional antenna of at least one of the plurality of nodes comprises a plurality of segments, wherein a first one of the plurality of segments permits communications in the first direction, and wherein a second one of the plurality of segments permits communications in the second direction.

16. The sensor network of claim 1 further comprising:

a second command center; and

a second access node coupled to the second command center, wherein the second command center and the second access node are located in the downlink direction relative to the first access node, and wherein the second access node is located to wirelessly communicate with a terminating node of the plurality of nodes.

17. The sensor network of claim 1 wherein the wireless transceiver of each of the plurality of nodes comprises a wideband transceiver which transmits and receives communication bursts having a bandwidth of at least two percent of a center frequency of the bursts.

18. The sensor network of claim 1 wherein the wireless transceiver of each of the plurality of nodes comprises a wideband transceiver which transmits and receives communication bursts having a bandwidth of at least ten percent of a center frequency of the bursts.

19. The sensor network of claim 1 wherein the wireless transceiver of each of the plurality of nodes comprises a wideband transceiver which transmits and receives communication bursts having a bandwidth of at least twenty percent of a center frequency of the bursts.

20. The sensor network of claim 1, further comprising:

a plurality of sensor devices individually coupled with one of the plurality of nodes, the plurality of sensor devices each providing sensor data for the first command center.

21. The sensor network of claim 1, wherein at least one of the plurality of nodes is coupled with a plurality of sensors, the plurality of sensors each providing sensor data for the command center.

22. The sensor network of claim 1, wherein the sensor device of at least one of the plurality of nodes is a sensor selected from the group consisting of:

a temperature sensor, a light sensor, a motion sensor, and a radar sensor.

23. The sensor network of claim 1, wherein the first access node and the plurality of nodes define a linear network of wireless nodes.

24. A method for scheduling data transmission in a wireless network having a plurality of nodes successively located in an uplink direction and providing a communication link to an access node coupled to a command center, wherein each given node of the plurality of nodes includes a neighbor group comprising at least two nodes located within an effective wireless transmission range in the uplink direction of the given node, the method comprising:

transmitting data from a transmitting node of the plurality of nodes to a receiving node in an associated neighbor group of the plurality of neighbor groups during a first series of staggered time slots;

receiving the data at the receiving node during the first series of staggered time slots; and

performing the transmitting and the receiving for multiple transmitting nodes and a corresponding multiple receiving nodes of the plurality of nodes during the first series of staggered time slots.

25. The method of claim 24, further comprising:

transmitting data from a transmitting node of the plurality of nodes to a receiving node in an associated neighbor group of the plurality of neighbor groups during a second series of staggered time slots; and

receiving the data at the receiving node during the second series of staggered time slots.

26. The method of claim 25, wherein the receiving node in a previous time slot of the first series of staggered time slots is the transmitting node in a later time slot of the second series of staggered time slots.

27. The method of claim 25, further comprising:

interlacing the first series of staggered time slots with the second series of staggered time slots.

28. The method of claim 25, wherein each time slot of the second series of staggered time slots individually follow a respective time slot of the first series of staggered time slots.

29. The method of claim 25, further comprising:

performing the transmitting and the receiving for multiple transmitting nodes and a corresponding multiple receiving nodes of the plurality of nodes during the second series of staggered time slots.

30. The method of claim 24, wherein the multiple transmitting nodes transmitting during the first series of staggered time slots are different than the multiple transmitting nodes transmitting during the second series of staggered time slots.

31. The method of claim 24, further comprising:

repeating the performing unless an expected receiving node of the associated neighbor group is identified as a failed node; and

if the expected receiving node is a failed node, transmitting the received data to an alternative receiving node of the associated neighbor group during a time slot of the first series of time slots, and receiving the data at the alternative receiving node during the time slot of the first series of time slots.

32. The method of claim 24, wherein the first series of staggered times slots are staggered by a factor of one.

33. The method of claim 24, further comprising:

receiving an instruction provided by the command center; and

performing the transmitting of the data responsive to the instruction.

34. The method of claim 24, further comprising:

receiving at the access node, data transmitted by a terminating node of a final neighbor group of the neighbor groups; and

transmitting the received data by the access node to the command center.

35. The method of claim 24, further comprising:

generating the data by a sensor operatively coupled to a node of the plurality of nodes.

36. A method for node failure recovery in a wireless network having a plurality of nodes successively located in a downlink direction relative to an access node coupled to a first command center, wherein each given node of the plurality of nodes includes a first neighbor group comprising nodes located within an effective wireless transmission range in the uplink direction of the given node and a second neighbor group comprising nodes located within an effective wireless transmission range in the downlink direction of the given node, the method comprising:

detecting by a particular node of the plurality of nodes that a recurring communication has not been received by the particular node, within a time period, from a neighbor node in either of the first neighbor group or the second neighbor group;

communicating a first indicator to the command center indicating that the neighbor node is a failed node; and

transmitting an update neighbor information command to all nodes which are in the first neighbor group and the second neighbor group of the failed neighbor node, causing such nodes to respectively update the first neighbor group and the second neighbor group to omit the failed neighbor node.

37. The method of claim 36, wherein after the update, the method further comprises:

communicating an update notification to the command center notifying completion of the update.

38. The method of claim 36, further comprising:

transmitting an initialization command successively in the downlink direction to each node of the plurality of nodes, the initialization command establishing a relative sequence of each of the plurality of nodes.

39. The method of claim 38, wherein the access node is a first access node and the command center is a first command center, the method further comprising:

receiving the initialization command at a second command center via a second access node in wireless communication with a last node of the plurality of nodes; and

communicating a resume command from the second command center to the first command center responsive to the receiving of the initialization command, wherein the communicating of the resume command is performed by successively transmitting, in an uplink direction, the resume command by each node of the plurality of nodes.

40. The method of claim 36, wherein the recurring communication comprises a beacon.

41. The method of claim 38, wherein the access node is a first access node and the command center is a first command center, the method further comprising:

receiving the initialization command at a last node of the plurality of nodes, wherein the last node is configured to function as a second command center; and

communicating a resume command from the last node to the first command center responsive to the receiving of the initialization command, wherein the communicating of the resume command is performed by successively transmitting, in an uplink direction, the resume command by each node of the plurality of nodes.

42. A sensor network comprising:

a plurality of nodes individually comprising a wireless transceiver and a directional antenna, wherein each of the plurality of nodes is successively located in a downlink direction relative to an access node, and is configured to wirelessly communicate via the directional antenna with at least one node of a first neighbor group in a first direction and at least one node of a second neighbor group in a second direction, and wherein each of the plurality of nodes is further configured to repeatedly transmit a signal using different segments of the directional antenna;

a sensor device individually coupled to at least one of the plurality of nodes and configured to provide sensor data; and

a mobile node configured to be operable at varying geographical locations within an operational range of the sensor network, wherein the mobile node comprises a wireless transceiver and is configured to establish wireless communications with an associated node of the plurality of nodes responsive to receiving the signal from the associated node.

43. The sensor network of claim 42, wherein the signal comprises a beacon signal.

44. The sensor network of claim 42, wherein the mobile node comprises an omni-directional antenna to facilitate the receiving of the signal.

45. The sensor network of claim 42, wherein each of the plurality of nodes is configured to receive location information associated with a location of the mobile node, and wherein a particular segment or segments of the segments of the directional antenna is utilized to transmit the signal is based upon the location information.

46. The sensor network of claim 42, wherein each of the plurality of nodes is a fixed node configured to operate in a fixed geographical location.

47. A method for discovering a mobile node operating in association with a sensor network having a plurality of nodes individually comprising a wireless transceiver and a directional antenna, wherein each of the plurality of nodes is successively located in a downlink direction relative to an access node, the method comprising:

wirelessly communicating, by each of the plurality of nodes, with at least one node of a first neighbor group in a first direction and at least one node of a second neighbor group in a second direction;

repeatedly transmitting, by each of the plurality of nodes, a signal using different segments of the directional antenna;

receiving the signal at a mobile node from an associated node of the plurality of nodes; and

establishing wireless communication between the mobile node and the associated node responsive to receiving of the signal from the associated node.

48. The method of claim 47, wherein the signal comprises a beacon signal.

49. The method of claim 47, further comprising:

receiving the signal at the mobile node utilizing an omni-directional antenna coupled to the mobile node.

50. The method of claim 47, further comprising:

receiving location information associated with a location of the mobile node at each of the plurality of nodes; and

transmitting the signal by the associated node, based upon the location information, using a particular segment or segments of the segments of the directional antenna.

51. The method of claim 47, wherein each of the plurality of nodes is a fixed node configured to operate in a fixed geographical location.