Adaptive beacon interval in WLAN

• US 20040192284A1
• Filed: 03/25/2003
• Published: 09/30/2004
• Est. Priority Date: 03/25/2003
• Status: Active Grant

• Current Assignee: Nokia Corporation
• Original Assignee: Nokia Corporation
• Inventors: Haverinen, Henry, Orava, Pekka, Vaisanen, Ari
• Granted Patent: US 7,333,460 B2
• Time in Patent Office: Days
• US Class Current: 455/422.1
• CPC Class Codes: H04W 48/12 using downlink control channel

Abstract

The present invention relates to Wireless Local Area Networks and Access Points in such networks, in particular it relates to the control and use of varying beacon intervals in such networks. According to the present invention, the beacon frames in the Wireless Local Area Network are provided with an adaptive beacon interval. The interval is adapted in dependence on a current network load such that the length of the beacon interval is decreased when the network load is decreased and increased when network load is increased. The invention is applicable in existing as well as future IEEE 802.11 standards.

Claims

1. A method for controlling transmission of beacon frames from an Access Point in a Wireless Local Area Network, the method including:

transmitting the beacon frames with an adaptive beacon interval in dependence on a current network load during operation of the network, by

decreasing an adaptive beacon interval length when the network load is decreased and

increasing said adaptive beacon interval length when network load is increased.

2. The method as claimed in claim 1, including:

measuring the network load as the load of the Access Point.

3. The method as claimed in claim 1, including:

measuring the network load as the occupancy level of a channel used by the Access Point on the wireless medium.

4. The method as claimed in claim 1, including:

measuring the network load as the combination of the load of the Access Point and the occupancy level of a wireless medium for a channel used by the Access point for transmitting the beacon frames.

5. The method as claimed in claim 1, the Access Point having a fixed beacon interval configured prior to its operation, the method including:

adding additional beacons at subintervals between the beacons with the fixed beacon interval in order to provide an overall beacon interval that forms said adaptive beacon interval.

6. The method as claimed in claim 5, wherein the subinterval is chosen such that the fixed beacon interval divided with the subinterval forms an integer value.

7. The method as claimed in claim 6, including:

measuring the network load as the load of the Access Point.

8. The method as claimed in claim 6, including:

measuring the network load as the occupancy level of a channel used by the Access Point on the wireless medium.

9. The method as claimed in claim 6, including:

measuring the network load as the combination of the load of the Access Point and the occupancy level of a wireless medium for a channel used by the Access point for transmitting the beacon frames.

10. An Access Point providing beacon frames in a Wireless Local Area Network, the Access Point including:

transmitting means for transmitting the beacon frames with an adaptive beacon interval in dependence on a current network load during operation of the network, and

a signal processor for decreasing the length of the adaptive beacon interval when the network load is decreased and increasing the length of the adaptive beacon interval when network load is increased.

11. The Access Point as claimed in claim 10, including:

measuring means for measuring the network load as the load of the Access Point.

12. The Access Point as claimed in claim 10, including:

measuring means for measuring the network load as the occupancy level of a channel used by the Access Point on the wireless medium.

13. The Access Point as claimed in claim 10, including:

measuring means for measuring the network load as the combination of the load of the Access Point and the occupancy level of a wireless medium for a channel used by the Access point for transmitting the beacon frames.

14. The Access Point as claimed in claim 10, the Access Point having a fixed beacon interval configured prior to its operation, the Access Point including:

processing means for adding additional beacons at subintervals between the beacons with the fixed beacon interval in order to provide an overall beacon interval that forms said adaptive beacon interval.

15. The Access Point as claimed in claim 14, wherein the subinterval is chosen such that the fixed beacon interval divided with the subinterval forms an integer value.

16. The Access Point as claimed in claim 15, including:

measuring means for measuring the network load as the load of the Access Point.

17. The Access Point as claimed in claim 15, including:

measuring means for measuring the network load as the occupancy level of a channel used by the Access Point on the wireless medium.

18. The Access Point as claimed in claim 15, including:

measuring means for measuring the network load as the combination of the load of the Access Point and the occupancy level of a wireless medium for a channel used by the Access point for transmitting the beacon frames.

19. A Wireless Local Area Network including an Access Point providing beacon frames and a wireless station for receiving said beacon frames, the Access Point having a fixed beacon interval configured prior to its operation, the Access Point including:

processing means for adding additional beacons at subintervals between the beacons with the fixed beacon interval in order to provide an overall beacon interval that forms said adaptive beacon interval.

20. The Wireless Local Area Network as claimed in claim 19, wherein the subinterval is chosen such that the fixed beacon interval divided with the subinterval forms an integer value.

21. The Wireless Local Area Network as claimed in claim 20, wherein said Access Point includes:

measuring means for measuring the network load as the load of the Access Point.

22. The Wireless Local Area Network as claimed in claim 20, wherein said Access Point includes:

measuring means for measuring the network load as the occupancy level of a channel used by the Access Point on the wireless medium.

23. The Wireless Local Area Network as claimed in claim 20, wherein said Access Point includes:

measuring means for measuring the network load as the combination of the load of the Access Point and the occupancy level of a wireless medium for a channel used by the Access point for transmitting the beacon frames.

24. The Wireless Local Area Network as claimed in claim 19, wherein the included wireless station is a mobile phone with WLAN capabilities, or a portable computer with a plug-in card having WLAN capabilities.