Receiver scheduling in ad hoc wireless networks

• US 7,421,257 B1
• Filed: 12/23/2002
• Issued: 09/02/2008
• Est. Priority Date: 11/30/2001
• Status: Active Grant

• Current Assignee: III Holdings 1, LLC
• Original Assignee: Stragent, LLC (Oso IP, LLC)
• Inventors: Elliott, Brig Barnum
• Primary Examiner(s): Nguyen, Duc
• Assistant Examiner(s): Perez, Julio R
• Application Number:
  US10/328,566
• Time in Patent Office: 2,080 Days
• Field of Search: 455/522, 455/420, 455/38.3, 455/343, 455/517, 455/572, 455/574.1, 455/127.5, 370/390, 370/219, 370/221, 370/400, 370/345, 709/248, 709/217, 709/219, 709/225
• US Class Current: 455/127.5
• CPC Class Codes: H04J 3/16 in which the time allocation to individual channels within a transmission cycle is variable, e.g. to accommodate varying complexity of signals, to vary number of channels transmitted H04J3/17, H04J3/24 take precedence
• CPC Class Codes: H04W 52/0216 using a pre-established activity schedule, e.g. traffic indication frame
• CPC Class Codes: H04W 52/0219 where the power saving management affects multiple terminals
• CPC Class Codes: H04W 56/00 Synchronisation arrangements
• CPC Class Codes: H04W 72/12 Wireless traffic scheduling
• CPC Class Codes: H04W 72/20 Control channels or signalling for resource management
• CPC Class Codes: H04W 84/18 Self-organising networks, e.g. ad-hoc networks or sensor networks
• CPC Class Codes: Y02D 30/70 in wireless communication networks

Abstract

A wireless network (100) includes a communications node (120) configured to periodically generate and transmit at least one reception definition. Each reception definition indicates a time and manner in which the node will operate to receive information messages.

Claims

1. A wireless network, comprising:

a node configured to periodically generate and transmit at least one reception definition, each of the at least one reception definition indicating a time and manner in which the node will operate to receive information messages, the time including a time at which the node will power up a receiver to receive the information messages where, when generating the at least one reception definition, the node is configured to derive parameters delineating each of the at least one reception definition via pseudo-random number generation or physical random number generation.

2. The wireless network of claim 1, wherein the node transmits a reception definition by including the reception definition with information messages bound for other network nodes.

3. The wireless network of claim 1, wherein the node is further configured to:

generate a local receiver schedule including a number of reception definitions,

periodically modify the local receiver schedule, and

transmit a prevailing local receiver schedule together with information messages bound for other network nodes.

4. The wireless network of claim 3, wherein, when modifying the local receiver schedule, the node is configured to:

periodically select a first reception definition from the local receiver schedule,

receive incoming information messages in accordance with the selected first reception definition,

remove the selected first reception definition from the local receiver schedule,

generate a new reception definition, and

5. The wireless network of claim 1, wherein the node is further configured to receive and subsequently transmit reception definitions generated and transmitted by other nodes.

6. The wireless network of claim 5 wherein the node generates the at least one reception definition based on at least one of the received reception definitions.

7. The wireless network of claim 5, wherein the node includes a local receiver schedule database configured to store reception definitions generated by the node and reception definitions received from the other nodes.

8. The wireless network of claim 7, wherein, when periodically transmitting reception definitions, the node is configured to:

analyze the local receiver schedule database to determine a next receiving node in the network,

determine whether any information messages are bound for the next receiving node, and

transmit at least a subset of the reception definitions stored in the local receiver schedule database together with at least one of the information messages bound for the next receiving node.

9. The wireless network of claim 7, wherein the local receiver schedule database is configured to store a data structure including at least one node receiver schedule.

10. The wireless network of claim 9, wherein each node receiver schedule in the data structure includes a node identification field and an array of reception definitions.

11. The wireless network of claim 10, wherein each reception definition in the data structure includes a reception start time, a reception duration, and a reception channel.

12. The wireless network of claim 1 wherein the time included in the at least one reception definition further includes a duration time period, the node being configured to power down the receiver after the duration time period has lapsed.

13. A node for use in a wireless network, comprising:

a memory configured to store instructions, and

a processor configured to execute the instructions to;

generate a local receiver schedule including a number of reception definitions, each reception definition indicating a time and manner in which the node will operate to receive information messages, the time including a time at which the node will power up a receiver to receive the information messages,

periodically modify the local receiver schedule, and

cause a prevailing local receiver schedule to be transmitted together with information messages bound for other nodes in the wireless network.

14. The node of claim 13, wherein, when periodically modifying the local receiver schedule, the processor is configured to:

select a first reception definition from the local receiver schedule,

receive incoming information messages in accordance with the selected reception definition,

remove the selected reception definition from the local receiver schedule,

generate a new reception definition, and

append the new definition to the local receiver schedule.

15. The node of claim 13, wherein, when causing a prevailing local receiver schedule to be transmitted together with information messages bound for other nodes in the wireless network, the processor is configured to:

identify a next receiving node from among the other nodes in the wireless network,

determine whether an information message is bound for the identified next receiving node, and

when an information message is bound for the identified next receiving node, cause the prevailing local receiver schedule to be transmitted together with at least one information message to the identified next receiving node.

16. The node of claim 15, further comprising a local receiver schedule database configured to store reception definitions generated by the node and reception definitions received by the node from other nodes in the wireless network.

17. The node of claim 16 wherein the processor generates the local receive schedule based on the received reception definitions.

18. The node of claim 16, wherein, when identifying the next receiving node, the processor is configured to analyze the local receiver schedule database to determine an earliest start time among stored reception definitions associated with other network nodes.

19. The node of claim 16, wherein, when causing the prevailing local receiver schedule to be transmitted together with at least one information message to the identified next receiving node, the processor is configured to additionally cause reception definitions associated with other network nodes to be transmitted together with at least one information message to the identified next receiving node.

20. The node of claim 16, wherein the local receiver schedule database is configured to store a data structure including at least one node receiver schedule.

21. The node of claim 20, wherein each node receiver schedule in the data structure includes a node identification field and an array of reception definitions.

22. The node of claim 21, wherein each reception definition in the data structure includes a reception start time, a reception duration, and a reception channel.

23. The node of claim 13 wherein the time indicated in the reception definition further includes a duration time period, the processor being configured to power down the receiver after the duration time period has lapsed.

24. A method of performing receiver scheduling at a node in a wireless network, the wireless network including a plurality of nodes, the method comprising:

generating a local receiver schedule at the node, the local receiver schedule including a number of reception definitions, each reception definition indicating a time and manner in which the node will operate to receive information messages from other nodes in the network, the time including a time at which the node will power up a receiver to receive the information messages;

periodically updating the local receiver schedule at the node; and

periodically transmitting a most recently updated local receiver schedule from the node to other nodes in the network.

25. The method of claim 24, wherein periodically updating the local receiver schedule includes:

selecting a first reception definition from the local receiver schedule, receiving incoming information messages in accordance with the selected definition, removing the selected reception definition from the local receiver schedule, generating a new reception definition, and appending the new reception definition to the local receiver schedule.

26. The method of claim 24, wherein transmitting a most recently updated local receiver schedule from the node to other nodes in the network includes:

identifying a next receiving node among the other nodes in the wireless network, and

transmitting the most recently updated local receiver schedule together with at least one information message bound for identified next receiving node.

27. The method of claim 24 wherein the time indicated in the reception definition further includes a duration time period, the node being configured to power down the receiver after the duration time period has lapsed.

28. A computer readable medium encoded with instructions for controlling at least one node to perform a method, comprising:

generating a local receiver schedule, the local receiver schedule including a number of reception definitions, each reception definition indicating a time and manner in which the node will operate to receive information messages, the time including a time at which the node will power up a receiver to receive the information messages;

periodically updating the local receiver schedule; and

causing a most recently updated local receiver schedule to be transmitted together with information messages bound for other network nodes.

29. The computer-readable medium of claim 28 wherein the time indicated in the reception definition further includes a duration time period, the node being configured to power down the receiver after the duration time period has lapsed.