Communicating over a wireless network

• US 20060285579A1
• Filed: 05/31/2006
• Published: 12/21/2006
• Est. Priority Date: 06/01/2005
• Status: Active Grant

• Current Assignee: III Holdings 3, LLC
• Original Assignee: Woodford Farm Trust
• Inventors: Liu, Sheng, Rhee, Sokwoo
• Granted Patent: US 7,844,308 B2
• Time in Patent Office: Days
• US Class Current: 375/132
• CPC Class Codes: H04B 1/713 using frequency hopping
• CPC Class Codes: H04B 1/7156 Arrangements for sequence synchronisation
• 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 52/0229 where the received signal is a wanted signal
• 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 first device communicates with a wireless network that includes nodes that are active for predefined activation times and that are at least partially dormant when not active. The communication method includes identifying a start of communication via a message that exceeds a maximum activation time of nodes on the wireless network by a factor N, where N is equal to at least a maximum number of frequencies on the wireless network, and exchanging information with a second device comprising a node on the wireless network that is within a transmission range of the first device, where the information is exchanged following the message and includes frequency hopping data for the second device.

Claims

1. A method, performed by a first device, for communicating with a wireless network comprised of nodes that are active for predefined activation times and that are at least partially dormant when not active, the method comprising:

identifying a start of communication via a message that exceeds a maximum activation time of nodes on the wireless network by a factor N, where N is equal to at least a maximum number of frequencies on the wireless network; and

exchanging information with a second device comprising a node on the wireless network that is within a transmission range of the first device, wherein the information is exchanged following the message and includes frequency hopping data for the second device.

2. The method of claim 1, wherein the information exchanged following the message includes frequency hopping data for the first device.

3. The method of claim 1, wherein the information is exchanged over multiple frequencies through which the first device hops following the message, the multiple frequencies being following the message.

4. A method performed by a first device for use in conjunction with a wireless network, the method comprising:

outputting a preamble to the wireless network, the preamble containing time data corresponding to a duration of the preamble;

identifying one or more listening frequencies of the first device that follow the preamble, the one or more listening frequencies comprising one or more frequency bands at which the first device activates;

receiving, from a second device in the wireless network and in the one or more listening frequencies, sequence data, wake-up data, and duty cycle data, the sequence data being usable to obtain a sequence of frequencies at which the second device activates, the wake-up data corresponding to times at which the second device activates, and the duty cycle data being based on durations of time for which the second device activates; and

storing the sequence data, wake-up data, and duty cycle data.

5. The method of claim 4, further comprising outputting, to the second device, a search packet, the search packet being output following the preamble and before receiving the sequence data, the wake-up data, and the duty cycle data from the second device, the search packet identifying the first device and containing sequence data, wake-up data, and duty cycle data for the first device.

6. The method of claim 4, wherein the wireless network comprises N (N>

2) devices including the second device, each of the N devices being configured to activate at a frequency in a sequence of M (M>

1) frequencies, the N devices activating for time intervals, one of the N devices having a maximum activation time interval of T, the preamble having a time duration that is at least a product of M*T.

7. The method of claim 4, wherein the one or more listening frequencies comprise a single listening frequency, the single listening frequency being a same frequency at which the preamble is output.

8. The method of claim 4, wherein the one or more listening frequencies comprise multiple listening frequencies, the search packet identifying sequence data and duty cycle data for the multiple listening frequencies.

9. The method of claim 4, wherein the sequence data comprises a single number, the first device generating the sequence of frequencies at which the second device activates by processing the single number using a predefined algorithm.

10. The method of claim 4, wherein the sequence data is first sequence data, the wake-up data is first wake-up data, and the duty cycle data is first duty cycle data;

and

wherein the method further comprises;

receiving, from a third device in the wireless network, second sequence data, second wake-up data, and second duty cycle data, the second sequence data being usable to obtain a sequence of frequencies at which the third device activates, the second wake-up data corresponding to times at which the third device activates, and the second duty cycle data being based on durations of time for which the third device activates;

wherein the first sequence data, the first wake-up data, and the first duty cycle data are received in a same listening frequency following the preamble, but at different times than, the second sequence data, the second wake-up data, and the second duty cycle data.

11. The method of claim 4, further comprising:

receiving, from the second device and in the one or more listening frequencies, sequence data, wake-up data, and duty cycle data, for a third device in the wireless network, wherein the third device is not within a wireless transmission range of the first device.

12. The method of claim 4, further comprising:

sending a communication to the second device using the sequence data, the wake-up data, and the duty cycle data;

wherein sending the communication comprises;

sending a second preamble, the second preamble being sent at a frequency specified in the sequence data, at about a time specified in the wake-up data, and for a duration that exceeds a duration specified in the duty cycle data;

receiving an acknowledgement signal from the second device in response to the second preamble; and

sending information for the communication following the second preamble and in response to the acknowledgement signal, the information being sent in a same frequency as the second preamble.

13. The method of claim 4, wherein the preamble comprises a series of data packets transmitted in sequence, the data packets containing the time data from which the duration of the preamble can be determined.

14. A device comprising:

memory configured to store instructions that are executable; and

at least one processor configured to execute the instructions to;

enter an activation mode to communicate over a wireless network; and

enter a dormant mode periodically, the at least one processor performing fewer tasks in the dormant mode than in the activation mode;

wherein to configure the device for communication or broadcast over the wireless network, the at least one processor executes instructions to;

output a preamble to the wireless network, the preamble containing time data corresponding to a duration of the preamble;

identify one or more listening frequencies of the device that follow the preamble, the one or more listening frequencies comprising one or more frequency bands at which the device enters the activation mode following the preamble;

receive, from a node in the wireless network and in the one or more listening frequencies, sequence data, wake-up data, and duty cycle data, the sequence data being usable to obtain a sequence of frequencies at which the node activates, the wake-up data corresponding to times at which the node activates, and the duty cycle data being based on durations of time for which the node activates; and

store the sequence data, wake-up data, and duty cycle data.

15. One or more machine-readable media for storing instructions that are executable by a first device for use with a wireless network, the instructions to:

output a preamble to the wireless network, the preamble containing time data corresponding to a duration of the preamble;

identify one or more listening frequencies of the first device that follow the preamble, the one or more listening frequencies comprising one or more frequency bands at which the first device activates;

receive, from a second device in the wireless network and in the one or more listening frequencies, sequence data, wake-up data, and duty cycle data, the sequence data being usable to obtain a sequence of frequencies at which the second device activates, the wake-up data corresponding to times at which the second device activates, and the duty cycle data being based on durations of time for which the second device activates; and

store the sequence data, wake-up data, and duty cycle data.

16. A method, performed by a node in a wireless network, comprising:

receiving a preamble from a device, the preamble containing time data corresponding to a duration of the preamble;

identifying one or more listening frequencies of the device that follow the preamble, the one or more listening frequencies comprising one or more frequency bands at which the device activates; and

sending, to the device and in the one or more listening frequencies, sequence data, wake-up data, and duty cycle data, the sequence data being usable to obtain a sequence of frequencies at which the node activates, the wake-up data corresponding to times at which the node activates, and the duty cycle data being based on durations of time for which the node activates.

17. The method of claim 16, wherein the sequence data, the wake-up data, and the duty cycle data are sent at a time that is obtained to reduce conflict with other nodes sending data to the device following the preamble.

18. A system comprising:

a wireless network comprised of plural nodes, at least some of the nodes having an activation time during which the at least some nodes are active;

a first device configured to identify a start of communication via a message that exceeds a maximum activation time of nodes on the wireless network by a factor N, where N is equal to at least a maximum number of frequencies on the wireless network;

a second device comprising a node on the wireless network, the second device being configured to respond to the message with frequency hopping data, the frequency hopping data identifying how the second device performs frequency hopping to receive data.

19. The system of claim 18, wherein the first devices identifies one or more frequencies that follow the message, the second device being configured to respond to the message in the one or more frequencies, wherein a response to the message by the second device is timed to reduce conflict with possible messages from other devices on the wireless network.

20. The system of claim 18, wherein the message comprises a preamble containing time data corresponding to a duration of the preamble, and one or more listening frequencies of the first device follow the preamble, the one or more listening frequencies comprising one or more frequency bands at which the first device activates;

wherein the second device is configured to respond to the message in the one or more listening frequencies; and

wherein the frequency hopping data comprises sequence data, wake-up data, and duty cycle data, the sequence data being usable to obtain a sequence of frequencies at which the second device activates, the wake-up data corresponding to times at which the second device activates, and the duty cycle data being based on durations of time for which the second device activates.