Method and apparatus for transmitting control frame to hidden node in wireless LAN

• US 20070217352A1
• Filed: 11/15/2006
• Published: 09/20/2007
• Est. Priority Date: 01/05/2006
• Status: Active Grant

• Current Assignee: Sisvel International S.A. (Fineur International S.A.)
• Original Assignee: Samsung Electronics Co. Ltd.
• Inventors: Kwon, Chang-yeul
• Granted Patent: US 7,944,874 B2
• Time in Patent Office: Days
• US Class Current: 370/312
• CPC Class Codes: H04W 4/06 Selective distribution of broadcast services, e.g. multimedia broadcast multicast service [MBMS]; Services to user groups; One-way selective calling services
• CPC Class Codes: H04W 48/08 Access restriction or access information delivery, e.g. discovery data delivery signalling during connection H04W76/00
• CPC Class Codes: H04W 48/16 Discovering, processing access restriction or access information
• CPC Class Codes: H04W 74/00 Wireless channel access
• CPC Class Codes: H04W 74/006 in the downlink, i.e. towards the terminal
• CPC Class Codes: H04W 74/08 Non-scheduled access, e.g. ALOHA hybrid access H04W74/02
• CPC Class Codes: H04W 8/26 Network addressing or numbering for mobility support
• CPC Class Codes: H04W 84/12 WLAN [Wireless Local Area Networks]
• CPC Class Codes: H04W 88/04 adapted for relaying to or from another terminal or user
• CPC Class Codes: H04W 88/08 Access point devices

Abstract

A method and apparatus informs nodes included in a wireless local area network (LAN) of how to avoid access collision in a wireless LAN. A wireless LAN access point or an independent basic service set (IBSS) control station receives a Contention-Free-End (CF-End) frame, compares a basic service set ID (BSSID) of the received CF-End frame of the access point or the IBSS, and rebroadcasts the received CF-End frame if the comparison result indicates that the two BSSIDs coincide with each other. Thus, all stations included in one BSS can receive the same time information for controlling medium access.

Claims

1. A method of delivering a control frame for a device which communicates through a wireless local area network (LAN), the method comprising:

receiving a control frame including time information for controlling medium access and recipient address information;

checking recipient address information; and

broadcasting the received control frame in a selective manner based on a checking result.

2. The method of claim 1, wherein, in the control frame, a duration field of a MAC (medium access control) header has a value of 0.

3. The method of claim 2, wherein the control frame is a Contention-Free-End (CF-End) frame.

4. The method of claim 3, wherein the broadcasting the received control frame comprises broadcasting the received CF-END frame if the checking result indicates that a basic service set ID (BSSID) recorded in the CF-End frame coincides with a BSSID of a BSS (basic service set).

5. The method of claim 4, wherein the broadcasting the received control frame further comprises broadcasting the received CF-END frame when a short inter-frame space (SIFS) elapses after the CF-End frame is received in (a).

6. The method of claim 1, wherein the wireless LAN is an infrastructure BSS, and the device is an access point of the infrastructure BSS.

7. The method of claim 1, wherein the wireless LAN is an IBSS (independent BSS), and the device is an IBSS control station that sends a beacon frame.

8. A computer-readable medium having embodied thereon a computer program for executing the method of claim 1.

9. A computer-readable medium having embodied thereon a computer program for executing the method of claim 2.

10. A computer-readable medium having embodied thereon a computer program for executing the method of claim 3.

11. A computer-readable medium having embodied thereon a computer program for executing the method of claim 4.

12. A computer-readable medium having embodied thereon a computer program for executing the method of claim 5.

13. A computer-readable medium having embodied thereon a computer program for executing the method of claim 6.

14. A computer-readable medium having embodied thereon a computer program for executing the method of claim 7.

15. An apparatus for delivering a control frame received through a wireless LAN, the apparatus comprising:

a recipient address information checking unit which checks recipient address information included in the control frame when the control frame including time information for medium access is received; and

a resending unit which broadcasts the received control frame in a selective manner based on the checking result.

16. The apparatus of claim 15, wherein, in the control frame, a duration field of a MAC header has a value of 0.

17. The apparatus of claim 16, wherein the control frame is a CF-End frame.

18. The apparatus of claim 17, wherein, the resending unit broadcasts the CF-End frame if the checking result indicates that a recipient address recorded in the CF-End frame is a broadcast address, and a BSSID recorded in the CF-End frame coincides with a BSSID of a BSS (basic service set).

19. The apparatus of claim 18, wherein, the resending unit broadcasts the received CF-End frame when a SIFS elapses after the CF-End frame.

20. An access point comprising the apparatus of claim 15.

21. A wireless LAN station which comprises the apparatus of claim 15, and operates the apparatus only when the wireless LAN station operates as an IBSS control station that sends a beacon frame in the independent BSS.