Method for transmitting a traffic indication message in a broadband wireless access communication system

• US 20050122936A1
• Filed: 11/08/2004
• Published: 06/09/2005
• Est. Priority Date: 11/07/2003
• Status: Active Grant

• Current Assignee: Samsung Electronics Co. Ltd.
• Original Assignee: Samsung Electronics Co. Ltd.
• Inventors: Son, Jung-Je, Koo, Chang-Hoi, Lee, Sung-Jin, Son, Yeong-Moon, Kim, So-Hyun, Kang, Hyun-Jeong
• Granted Patent: US 7,801,072 B2
• Time in Patent Office: Days
• US Class Current: 370/331
• CPC Class Codes: H04W 52/0216 using a pre-established activity schedule, e.g. traffic indication frame
• CPC Class Codes: H04W 68/025 Indirect paging
• CPC Class Codes: Y02D 30/70 in wireless communication networks

Abstract

A method for transmitting a traffic indication message for directing a mobile subscriber station (MSS) in a sleep mode to transition to an awake mode in a Broadband Wireless Access communication system supporting the sleep mode and the awake mode. This method includes the steps of individually allocating, to MSSs belonging to a corresponding base station, corresponding areas indicating traffic instructions for the MSSs in a traffic indication field in the traffic indication message, and indicating state transition instructions in the areas allocated to the MSSs, before transmitting the traffic indication message to the MSSs.

Claims

1. A method for transmitting a traffic indication message for directing a mobile subscriber station (MSS) in a sleep mode to transit to an awake mode in a Broadband Wireless Access communication system supporting the sleep mode when there is no transmission data and the awake mode when there is transmission data, the method comprising the steps of:

individually allocating each of corresponding MSS areas indicating traffic existence for MSSs belonging to a serving base station in a traffic indication field of the traffic indication message;

indicating state transition instructions in the areas; and

transmitting the traffic indication message to the MSSs.

2. The method of claim 1, wherein a size of each of the area individually allocated to the MSSs is 1 bit.

3. The method of claim 1, wherein the traffic indication message further includes a group information field indicting a number of groups, each group having a predetermined number of the MSSs belonging to the base station.

4. The method of claim 1, wherein an MSS receiving the traffic indication message from the base station state transitions according to a state transition instruction in an area allocated thereto in the traffic indication message.

5. A method for transitioning to an awake mode, by a mobile subscriber station (MSS) in a sleep mode, upon receiving a traffic indication message from a serving base station in a Broadband Wireless Access communication system supporting the sleep mode when there is no transmission data and the awake mode when there is transmission data, the method comprising the steps of:

receiving, by the MSS, a sleep identifier (SLPID) that is uniquely allocated thereto from the serving base station, when the MSS state transits from the awake mode to the sleep mode;

detecting, by the MSS, whether the allocated sleep identifier is included in the traffic indication message received from the base station; and

determining whether to state transit corresponding the determination result.

6. The method of claim 5, wherein the sleep identifier is received through a sleep response message.

7. The method of claim 6, wherein the sleep identifier included in the sleep response message replaces a basic connection identifier.

8. The method of claim 5, wherein when the MSS, which is allocated the sleep identifier, state transitions to the awake mode, the allocated sleep identifier is returned to the serving base station.

9. A method for transmitting a traffic indication message for directing a mobile subscriber station (MSS) in a sleep mode to transition to an awake mode in a Broadband Wireless Access communication system supporting the sleep mode when there is no transmission data and the awake mode when there is transmission data, the method comprising the steps of:

individually allocating corresponding each of MSSs areas indicating traffic existence for MSSs belonging to a serving base station in a traffic indication field in the traffic indication message;

indicating operation instruction information for the MSSs in the areas allocated thereto; and

transmitting the traffic indication message to the MSSs.

10. The method of claim 9, wherein a size of each of the areas individually allocated to the MSSs is 2 bits.

11. The method of claim 9, wherein the traffic indication message further includes a group information field indicating a number of groups, each group having a predetermined number of the MSSs belonging to the base station.

12. The method of claim 11, wherein each of the group has 4 MSSs.

13. The method of claim 9, wherein a MSS receiving the traffic indication message from the base station state transitions according to operation instruction information indicated in an area allocated thereto in the traffic indication message.

14. The method of claim 9, wherein the operation instruction information includes information for instructing a MSS to state transition to the awake mode.

15. The method of claim 9, wherein the operation instruction information includes information for instructing the MSS to maintain the sleep mode, after expiration of a corresponding listening interval.

16. The method of claim 9, wherein the operation instruction information includes information for instructing the MSS to immediately state transition to the sleep mode without waiting for a next traffic indication message for a corresponding listening interval.

17. A method for transmitting a traffic indication message from a base station to a plurality of mobile subscriber stations (MSSs) to notify the MSSs in a sleep mode when a plurality of the MSSs among MSSs located in a coverage of a base station are in the sleep mode, wherein the traffic indication message indicates whether there is data to be received, includes a traffic indication field including a stream of bits allocated to the MSSs, and includes information indicating if there is data to be received, in the bits for the MSSs.

18. The method of claim 17, wherein the base station individually allocating corresponding each of MSSs corresponding areas for indicating traffic instructions for MSSs belonging to a serving base station in a traffic indication field in the traffic indication message.

19. The method of claim 18, wherein the base station indicating operation instruction information for the MSSs in the corresponding areas allocated thereto, before transmitting the traffic indication message.

20. The method of claim 19, wherein the operation instruction information includes information for instructing the MSS to state transition to an awake mode.

21. The method of claim 19, wherein the operation instruction information includes information for instructing the MSS to maintain the sleep mode, after expiration of a corresponding listening interval.

22. The method of claim 19, wherein the operation instruction information includes information for instructing the MSS to immediately state transition to the sleep mode without waiting for a next traffic indication message for a corresponding listening interval.

23. The method of claim 17, wherein a size of each of the areas individually allocated to the MSS is 1 bit.

24. The method of claim 17, wherein a size of each of the areas individually allocated to the MSS is 2 bits.

25. The method of claim 17, wherein the traffic indication field includes group information indicating a number of groups, each of the groups having a predetermined number of MSSs belonging to the base station.

26. The method of claim 17, wherein the MSS receiving the traffic indication message from the base station state transitions according to a state transition instruction indicated in an area allocated thereto in the traffic indication message.

27. The method of claim 17, wherein the information indicating whether there is data to be received by the MSSs is a unique sleep identifier.

28. The method of claim 27, wherein the sleep identifier is received through a sleep response message.

29. The method of claim 28, wherein the sleep identifier included in the sleep response message replaces a basic connection identifier.

30. The method of claim 27, wherein when the MSS state transitions to the awake mode, the sleep identifier is returned to the base station.

31. The method of claim 17, wherein when the MSS staying in the sleep mode state transitions to the awake mode upon receiving a traffic indication message from the base station, the MSS determines whether there is the sleep identifier in the received traffic indication message and determines whether to make a state transition corresponding the determination result.

32. A method for generating a message used when a serving base station informs each of mobile subscriber stations (MSSs) in a sleep mode whether there is traffic to be transmitted to each of the MSSs in a Broadband Wireless Access communication system having an awake mode where there is transmission data and the sleep mode where there is no transmission data, the method comprising the steps of:

allocating, by the serving base station, unique sleep identifiers to the MSSs in the sleep mode;

grouping the sleep identifiers by a predetermined number, and generating a first indication bitmap by combining areas indicating the grouped sleep identifiers;

generating a second indication bitmap indicating the predetermined number of the sleep identifiers;

generating a traffic indication message including the first indication bitmap and the second indication bitmap; and

transmitting the generated traffic indication message to the MSSs.

33. The method of claim 32, wherein the sleep identifier is transmitted to the MSS through a sleep response message.

34. The method of claim 32, wherein when there is traffic to be transmitted to at least one of the MSSs, each bit of the first indication bitmap indicates presence of transmission traffic.

35. The method of claim 32, further comprising the steps of:

detecting, by the MSS, a bit corresponding to its location from the first indication bitmap;

determining if there is traffic depending on the detected bit;

detecting the second indication bitmap, if it is determined that there is traffic; and

avoiding detecting the second indication bitmap, if it is determined that there is no traffic.

36. The method of claim 35, wherein when the second indication bitmap is detected, the MSS detects a bit corresponding to its location, and determining whether there is traffic depending on the detected bit.