Framework for hybrid ad-hoc networks

• US 20070115895A1
• Filed: 11/18/2005
• Published: 05/24/2007
• Est. Priority Date: 11/18/2005
• Status: Active Grant

• Current Assignee: Nytell Software LLC (Intellectual Ventures LLC)
• Original Assignee: TTI Inventions A LLC (Intellectual Ventures LLC)
• Inventors: Chen, Wai, Ling, Yibei, Yu, Paul
• Granted Patent: US 8,125,964 B2
• Time in Patent Office: Days
• US Class Current: 370/338
• CPC Class Codes: G01S 5/0289 of multiple transceivers, e.g. in ad hoc networks
• CPC Class Codes: H04W 40/04 based on wireless node resources
• CPC Class Codes: H04W 40/20 based on geographic position or location
• CPC Class Codes: H04W 76/27 Transitions between radio resource control [RRC] states
• CPC Class Codes: H04W 84/18 Self-organising networks, e.g. ad-hoc networks or sensor networks

Abstract

A hybrid mobile ad-hoc network and a method of operating the same, including a mobile network node and a plurality of static network nodes randomly distributed over a coverage area with a predetermined density. The static network nodes form a static infrastructure backbone of the hybrid mobile ad-hoc network. Position information of the static network nodes, either through position awareness or triangulation with reference to other static nodes enhances the network function. The method tracks mobile node position with a minimum of overhead because of the fixed infrastructure of static nodes. The infrastructure can self-heal by placing excess static nodes in a hibernating state, and activating those in response to the failure of a nearby static node.

Claims

1. A hybrid mobile ad-hoc network comprising:

a mobile network node; and

a plurality of static network nodes randomly distributed over a coverage area with a predetermined density forming a static infrastructure backbone of the hybrid mobile ad-hoc network.

2. The hybrid mobile ad-hoc network according to claim 1, wherein at least two of the static network nodes are position-aware.

3. The hybrid mobile ad-hoc network according to claim 2, wherein the position-aware nodes comprise one or more of GPS signal reception and decoding capability, capability to reference a known terrestrial radio beacon, and inertial tracking capability.

4. The hybrid mobile ad-hoc network according to claim 1, at least a subset of the plurality of static network nodes further comprising means for determining the relative position of neighboring static network nodes.

5. The hybrid mobile ad-hoc network according to claim 1, wherein at least a subset of said static network nodes comprises means for determining range between adjacent static network nodes.

6. The hybrid mobile ad-hoc network according to claim 1, wherein at least a subset of said static network nodes comprises a directional reception antenna and means for determining and azimuth of a received signal.

7. The hybrid mobile ad-hoc network according to claim 1, further comprising means for placing one or more static network nodes into a hibernating state responsive to the determination that the local static network node density exceeds a predetermined threshold, or to the determination that the distance from another operating static network node is beneath a predetermined threshold.

8. The hybrid mobile ad-hoc network according to claim 1, wherein said static network nodes transmit a beacon to other nodes in the network at a periodic interval.

9. The hybrid mobile ad-hoc network according to claim 8, wherein a static network node is capable of operating in an active state or a hibernating state, and further wherein any static network node operating in the hibernating state responds to the absence of an expected beacon from the nearest static network node in the active state by entering the active state.

10. A method of operating a hybrid mobile ad-hoc network including a mobile network node comprising:

(a) randomly deploying a plurality of static network nodes over a coverage area in a predetermined density;

(b) determining the pair-wise network connectivity among the static network nodes in order to determine the network topography of an infrastructure backbone made up of the static network nodes; and

(c) communicating the infrastructure backbone topography information throughout the network.

11. The method according to claim 10, wherein at least two static network nodes are position-aware, the method further comprising determining the location of the position-aware static network nodes, and including the location of the position-aware static network nodes in the network backbone topography information.

12. The method according to claim 10, further comprising determining the relative position of adjacent static network nodes, and including the relative positions of the static network nodes in the network backbone topography information.

13. The method according to claim 12, wherein determining the relative position of neighboring static network nodes comprises triangulation by reference of the distance between difference between neighboring static network nodes.

14. The method according to claim 12, wherein determining the relative position of neighboring static network nodes comprises triangulation by reference of the azimuth between a static network node and a plurality of neighboring static network nodes.

15. The method according to claim 11, further comprising deactivating the location-determining capability of the position-aware static network nodes once their location has been determined.

16. The method according to claim 10, further comprising transmitting a beacon from each static network node to advise other nodes of its existence at a periodic interval.

17. The method according to claim 16, wherein the periodic interval is an adjustable network parameter.

18. The method according to claim 16, wherein each mobile network node responds to the beacon with a reply comprising information about the location of the mobile network node.

19. The method according to claim 18, wherein the reply further comprises bearing information about the mobile network node.

20. The method according to claim 18, further comprising communicating the reported location of each mobile network node throughout the network.

21. The method according to claim 16, wherein the static network node is capable of operating in an active state and a hibernating state, and further wherein any static network node operating in the hibernating state responds to the absence of an expected beacon from the nearest static network node in the active state by entering the active state.

22. The method according to claim 10, further comprising placing one or more static network nodes into a hibernating state if it is determined that one or more of (a) a local static network node density exceeds a predetermined threshold, or (b) distance from another operating static network node is beneath a predetermined threshold.

23. The method according to claim 10, further comprising coordinating transmissions among neighboring static network nodes.

24. The method according to claim 10, further comprising utilizing network topography information in making routing decisions.