Methods and apparatus to perform dynamic channel management and dynamic bandwidth changes in wireless local area networks

• US 20060291432A1
• Filed: 06/14/2006
• Published: 12/28/2006
• Est. Priority Date: 06/22/2005
• Status: Active Grant

• Current Assignee: Texas Instruments, Inc.
• Original Assignee: Texas Instruments, Inc.
• Inventors: Xhafa, Ariton E., Airy, Manish, Chhaya, Harshal Shantanu
• Granted Patent: US 7,796,566 B2
• Time in Patent Office: Days
• US Class Current: 370/336
• CPC Class Codes: H04W 28/20 Negotiating bandwidth
• CPC Class Codes: H04W 36/06 Reselecting a communication resource in the serving access point
• CPC Class Codes: H04W 72/23 in the downlink direction of a wireless link, i.e. towards a terminal
• CPC Class Codes: H04W 84/12 WLAN [Wireless Local Area Networks]

Abstract

Methods and apparatus to perform dynamic channel management and dynamic bandwidth changes in wireless local area networks are disclosed. A disclosed example method comprises deciding at an access point to initiate at least one of a bandwidth change or a channel assignment change; and sending a frame to initiate the at least one of the bandwidth change or the channel assignment change from the access point to one or more stations of a wireless network, the frame including a first field to identify a first channel and a second field to identify a second channel.

Claims

1. A method comprising:

deciding at an access point to initiate at least one of a bandwidth change or a channel assignment change; and

sending a frame to initiate the at least one of the bandwidth change or the channel assignment change from the access point to one or more stations of a wireless network, the frame including a first field to identify a first channel and a second field to identify a second channel.

2. A method as defined in claim 1, further comprising at least one of omitting or leaving blank the second field.

3. A method as defined in claim 1, wherein the frame is a dynamic channel switch frame including a receiver address field containing a broadcast address of the access point.

4. A method as defined in claim 1, wherein the bandwidth change is at least one of a change from 20 MHz operation to 40 MHz operation or from 40 MHz operation to 20 MHz operation.

5. A method as defined in claim 1, further comprising sending a clear-to-send frame on the first channel if the first channel was not previously being used by the wireless network.

6. A method as defined in claim 5, further comprising waiting a time duration that is at least a short interframe spacing plus a switching time before sending the clear-to-send frame.

7. A method as defined in claim 1, further comprising sending a contention-free end frame on at least one of the first channel, the second channel, or a third channel being replaced by at least one of the first or the second channel.

8. A method as defined in claim 7, further comprising waiting a time duration of at least a short interframe spacing before sending the contention-free end frame.

9. A method as defined in claim 1, further comprising:

receiving the frame at a first station of the wireless network; and

configuring at least one of a receiver or a transmitter of the first station based upon the first field and the second field.

10. A method as defined in claim 9, further comprising:

waiting to receive a contention-free end frame at the first station; and

resuming normal operation of the first station after the contention-free end frame is received.

11. A method comprising:

deciding at a first node of a wireless network to initiate a bandwidth change; and

sending a frame to initiate the bandwidth change from the first node to a second node of the wireless network, the frame including a receiver address field containing the medium access controller address of the first node.

12. A method as defined in claim 11, wherein the frame is a dynamic channel switch frame.

13. A method as defined in claim 11, wherein the bandwidth change is from 20 MHz operation to 40 MHz operation.

14. A method as defined in claim 11, wherein the first node is at least one of a station or an access point of the wireless network.

15. A method as defined in claim 11, wherein the second node is at least one of a station or an access point of the wireless network.

16. A method as defined in claim 11, further comprising:

receiving the frame at the second node; and

switching a receiver at the second node to 40 MHz operation.

17. A method as defined in claim 16, further comprising sending a clear-to-send frame addressed to the first node if the second node is an access point.

18. A method as defined in claim 16, wherein the second node is an access point, and further comprising:

deciding at the access point to initiate a channel assignment change; and

sending a second frame to initiate the channel assignment change from the access point to the first node, the second frame including a first field to identify a first channel and a second field to identify a second channel.

19. A method as defined in claim 18, further comprising at least one of omitting or leaving blank the second field.

20. A wireless network access point comprising:

a medium access controller to form a frame to initiate at least one of a bandwidth change or a channel assignment change, the frame including a first field to identify a first channel and a second field to identify a second channel; and

a wireless modem to send the frame from the access point to a station of the wireless network.

21. A wireless network access point as defined in claim 20, wherein the second field is at least one of omitted from or left blank in the frame.

22. A wireless network access point as defined in claim 20, wherein the frame is a dynamic channel switch frame including a receiver address field containing a broadcast address of the access point.

23. A wireless network access point as defined in claim 20, wherein the medium access controller is configured to form a clear-to-send frame, and the wireless modem is configured to send the clear-to-send frame on the first channel if the first channel was not previously being used by the wireless network.

24. A wireless network access point as defined in claim 20, wherein the medium access controller is configured to form a contention-free end frame, and the wireless modem is configured to send the contention-free end frame on at least one of the first channel, the second channel, or a third channel being replaced by at least one of the first or the second channel.

25. A wireless network access point as defined in claim 20, further comprising a processor to execute machine accessible instructions including the medium access controller.

26. An article of manufacture storing machine accessible instructions which, when executed, cause a machine to:

decide at an access point to initiate at least one of a bandwidth change or a channel assignment change; and

send a frame to initiate the at least one of the bandwidth change or the channel assignment change from the access point to one or more stations of a wireless network, the frame including a first field to identify a first channel and a second field to identify a second channel.

27. An article of manufacture as defined in claim 26, wherein the machine accessible instructions, when executed, cause the machine to at least one of omit or leave blank the second field.

28. An article of manufacture as defined in claim 26, wherein the frame is a dynamic channel switch frame including a receiver address field containing a broadcast address of the access point.

29. An article of manufacture as defined in claim 26, wherein the bandwidth change is at least one of a change from 20 MHz operation to 40 MHz operation or from 40 MHz operation to 20 MHz operation.