SYSTEM AND METHOD OF QOS-BASED CHANNEL SELECTION FOR WLAN ACCESS POINTS OR STATIONS

• US 20080279140A1
• Filed: 05/07/2007
• Published: 11/13/2008
• Est. Priority Date: 05/07/2007
• Status: Active Grant

• Current Assignee: Hitachi, Ltd.
• Original Assignee: Hitachi, Ltd.
• Inventors: Gaur, Sudhanshu
• Granted Patent: US 7,912,002 B2
• Time in Patent Office: Days
• US Class Current: 370/329
• CPC Class Codes: H04W 72/02 Selection of wireless resources by user or terminal
• CPC Class Codes: H04W 72/542 using measured or perceived quality
• CPC Class Codes: H04W 74/08 Non-scheduled access, e.g. ALOHA hybrid access H04W74/02
• CPC Class Codes: H04W 84/12 WLAN [Wireless Local Area Networks]

Abstract

A system comprises a candidate channel assessment module for obtaining at least one AC-specific channel suitability metric for each of two different channels, and for using the AC-specific channel suitability metrics to determine a channel suitability index of each of the two different channels; a channel selection module for using the channel suitability index to select one of the two different channels as a new channel; and a channel setting module for configuring a wireless transceiver to use the new channel.

Claims

1. A system comprising:

a candidate channel assessment module for obtaining at least one AC-specific channel suitability metric for each of two different channels, and for using the AC-specific channel suitability metrics to determine a channel suitability index of each of the two different channels;

a channel selection module for using the channel suitability index to select one of the two different channels as a new channel; and

a channel setting module for configuring a wireless transceiver to use the new channel.

2. The system of claim 1, wherein the system includes an access point.

3. The system of claim 2, wherein the access point communicates with a wireless station to obtain the at least one AC-specific channel suitability metric therefrom.

4. The system of claim 1, wherein fee channel assessment module applies the following equations to generate the channel suitability index (CSI):

CSI=Ψ

(LQ,CF)

where Ψ

indicates a function defining the relative success in transmitting a packet error free and is defined as;

Ψ

(LQ,CF)=LQ×

CF

where LQ indicates link quality and is defined as;

5. The system of claim 1, wherein the channel selection module selects the channel having the greatest channel suitability index.

6. The system of claim 1, wherein

the system includes a wireless station;

the candidate channel assessment module includes a BSS channel assessment module; and

the channel selection module includes a BSS channel selection module.

7. The system of claim 1, further comprising a current channel assessment module for determining when to initiate the candidate channel assessment module.

8. The system of claim 7, wherein the current channel assessment module initiates the candidate channel assessment module when a current channel link quality value fails a threshold test.

9. The system of claim 1, wherein, the AC-specific metric includes an AC-specific link quality metric and an AC-specific contention-faced metric.

10. The system of claim 1, wherein the wireless transceiver implements an IEEE 802.11e protocol.

11. A method comprising:

obtaining at least one AC-specific channel suitability metric for each of two different channels;

using the AC-specific channel suitability metrics to determine a channel suitability index of each of the two different channels;

using the channel suitability index to select one of the two different channels as a new channel; and

configuring a wireless transceiver to use the new channel.

12. The method of claim 11, operative in an access point.

13. The method of claim 12, further comprising communicating with a wireless station to obtain the at least one AC-specific channel suitability metric therefrom.

14. The method of claim 11, further comprising applying the following equations to generate the channel suitability index (CSI):

CSI=Ψ

(LQ,CF)

where Ψ

indicates a function defining the relative success in transmitting a packet error free and is defined as;

Ψ

(LQ,CF)=LQ×

CF

where LQ indicates link quality and is defined as;

15. The method of claim 11, further comprising selecting the channel having the greatest channel, suitability index.

16. The method of claim 11, operative in a wireless station.

17. The method of claim 11, further comprising determining when to initiate the candidate channel assessment module.

18. The method of claim 17, further comprising initiating the candidate channel assessment module when a current channel link quality value fails a threshold test.

19. The method of claim 11, wherein the AC-specific metric includes an AC-specific link quality metric and an AC-specific contention-faced metric.

20. A system comprising:

means for obtaining at least one AC-specific channel suitability metric for each of two different channels;

means for using the AC-specific channel, suitability metrics to determine a channel suitability index of each of the two different channels;

means for using the channel suitability index to select one of the two different channels as a new channel; and

means for configuring a wireless transceiver to use the new channel.