System and method for media access control for a duty cycle network

• US 20090046611A1
• Filed: 07/23/2008
• Published: 02/19/2009
• Est. Priority Date: 07/23/2007
• Status: Active Grant

• Current Assignee: The Boeing Co.
• Original Assignee: The Boeing Co.
• Inventors: Ma, Liangping, Zhu, Hua, Ryu, Bong K., Zhang, Zhensheng
• Granted Patent: US 8,767,696 B2
• Time in Patent Office: Days
• US Class Current: 370/311
• CPC Class Codes: H04W 4/90 Services for handling of emergency or hazardous situations, e.g. earthquake and tsunami warning systems [ETWS]
• CPC Class Codes: H04W 52/0216 using a pre-established activity schedule, e.g. traffic indication frame
• CPC Class Codes: H04W 76/50 for emergency connections
• CPC Class Codes: Y02D 30/70 in wireless communication networks

Abstract

A system and method for medium access control in a wireless communication network including the use of packets having a header and plural data portions, acknowledgement request features, corrupt packet identification, and adaptive duty cycling.

Claims

1. A method of medium access control for a wireless communication network having a plurality of wireless devices, each wireless device having a sleep mode and a wake-up mode, comprising the steps of:

(a) assembling a packet comprising;

(i) a preamble;

(ii) a first header; and

(iii) a plurality of data portions;

(b) transmitting the packet during a wake-up mode of a wireless device, wherein the size of the packet is less than the time interval of a sleep mode of the wireless device.

2. The method of claim 1, further comprising the step of:

(c) receiving the packet at a wireless device during its wake-up mode.

3. The method of claim 1 wherein the first header includes an indication of the number of data portions in the packet.

4. The method of claim 1 wherein the plurality of data portions are not the same length.

5. The method of claim 4 wherein each data portion includes a second header.

6. The method of claim 5 wherein the second header includes information to decode its respective data portion.

7. The method of claim 2 further comprising the step of:

(c) after the transmission of each data portion, waiting to receive an acknowledgement from the receiving wireless device before transmitting the next data portion.

8. The method of claim 2 further comprising the steps of:

(c) receiving an indication from the receiving wireless device that at least one data portion was not received; and

(d) retransmitting the data portion that was not received by the wireless device.

9. A method of medium access control for a wireless communication network having a plurality of wireless nodes, each wireless node having a duty cycle which controls a sleep mode and a wake-up mode, comprising the steps of:

(a) detecting an alert event at a source node

(b) determining a communication path between a source node and a destination node;

(c) identifying each node in the communication path;

(d) at each node in the communication path, changing the duty cycle of the node and transmitting an alert message to each wireless node adjacent to the transmitting node to indicate the change in duty cycle;

(f) at each adjacent node, storing the duty cycle change of the transmitting node; and

(g) transmitting a message from the source node to the destination node through the identified communication path.

10. The method of claim 9 further comprising the step of:

(f) at each node in the communication path, returning to the original duty cycle of the node by transmitting an alert message to each wireless node adjacent to the transmitting node in the communication path to indicate the change in duty cycle.

11. The method of claim 9 wherein the alert event is provided by a sensor.

12. The method of claim 11 wherein the sensor monitors environment conditions.

13. The method of claim 11 wherein the sensor is an intrusion detector.

14. A method of medium access control for a wireless communication network having a plurality of wireless devices, each wireless device having a sleep mode and a wake-up mode, comprising the steps of:

(a) receiving a packet during a wake-up mode of a wireless device,

(b) disassembling the packet, the packet comprising;

(i) a preamble;

(ii) a first header; and

(iii) a plurality of data portions;

wherein the size of the packet is less than the time interval of a sleep mode of the wireless device

15. The method of claim 14 wherein the first header includes an indication of the number of data portions in the packet.

16. The method of claim 14 wherein the plurality of data portions are not the same length.

17. The method of claim 14 further comprising the step of:

(c) after the receipt of each data portion, transmitting an acknowledgement from the receiving wireless device.

18. A method of medium access control for a wireless communication network having a plurality of wireless devices, each wireless device having a sleep mode and a wake-up mode and being powered by an energy source, comprising the steps of:

(a) classifying some of the plurality of nodes into backbone nodes and some of the plurality of nodes as non-backbone nodes based as a function of the remaining amount of energy at each node;

(b) making the backbone nodes available for relaying data'"'"'

(c) making the non-backbone nodes not available for relaying data.

19. The method of claim 18 wherein the step of classifying is performed periodically.

20. The method of claim 18 wherein the backbone nodes and the non-backbone nodes are made available for transferring their own data.

21. The method of claim 18 wherein the step of classifying includes classifying a node as a backbone node candidate if the remaining energy of the node exceeds a predetermined energy threshold.

22. The method of claim 18 wherein the step of classifying is invoked when a backbone node'"'"'s remaining energy level is below a given energy threshold.