Advance resource allocations for association state transitions for wireless LAN system

• US 20030050068A1
• Filed: 09/10/2001
• Published: 03/13/2003
• Est. Priority Date: 09/10/2001
• Status: Active Grant

• Current Assignee: Telefonaktiebolaget LM Ericsson
• Original Assignee: Telefonaktiebolaget LM Ericsson
• Inventors: Ulmehag, Lorens, Lindskog, Jan, Woxberg, Fredrik
• Granted Patent: US 7,570,952 B2
• Time in Patent Office: Days
• US Class Current: 455/450
• CPC Class Codes: H04W 28/26 Resource reservation
• CPC Class Codes: H04W 72/04 Wireless resource allocation
• CPC Class Codes: H04W 74/00 Wireless channel access
• CPC Class Codes: H04W 84/12 WLAN [Wireless Local Area Networks]

Abstract

A central controller (CC) [22] of a wireless local area network (LAN) [20], in conjunction with an association operation with a mobile terminal [24] and upon receiving from the mobile terminal (MT) a first control signal [CS 1 ] of a sequence of control signals involved in the association operation, pre-reserves a MAC resource for transmission of at least a further control signal in the sequence. The MAC resource for the further control signal is pre-reserved prior to information for the further control signal being stored in a transmission buffer [58] of the mobile terminal. In essence, judging from the nature of the first control signal, the central controller (CC) anticipates eventuality of the further control signal and pre-reserves the MAC resource for the further control signal. The central controller (CC) pre-reserves the MAC resource to avoid transmission of a separate message to request a MAC resource for the further control signal. In fact, in a preferred embodiment, the central controller (CC) pre-reserves MAC resources for the remaining control signals in the sequence. The association operation for which the pre-reservation occurs can be, for example, an initial association scenario or a handover scenario in which the mobile terminal (MT) is handed over to the central controller (CC). After the pre-reservation, the mobile terminal always has an uplink slot available for the remaining control signals in the sequence as a result of the central controller (CC) having pre-reserved the MAC resource. Optionally, the central controller (CC) can notify the mobile terminal (MT) 24 [using the Frame Control CHannel [FCCH] of the MAC frame] that the central controller (CC) has pre-reserved the MAC resources.

Claims

1. A wireless local area network (LAN) comprising:

a central controller;

a mobile terminal comprising;

a transceiver;

a transmission buffer which stores information to be included in a control signal; and

a MAC logic unit which, via the transceiver, sends a sequence of control signals to the central controller in a MAC protocol prior to sending/receiving user data;

wherein the central controller pre-reserves a MAC resource for transmission of a control signal in the sequence prior to information for the control signal being stored in the transmission buffer of the mobile terminal.

2. The apparatus of claim 1, wherein the central controller anticipates eventuality of the control signal and pre-reserves the MAC resource.

3. The apparatus of claim 1, wherein the MAC resource which is pre-re served by the central controller includes one of:

(1) an uplink Dedicated Control Channel (DCCH) Long Channel (LCH);

(2) an uplink Dedicated Control Channel (DCCH) Short Channel (SCH);

(3) a downlink Dedicated Control Channel (DCCH) Long Channel (LCH);

(4) a downlink Dedicated Control Channel (DCCH) Short Channel (SCH); and

(5) a combination of (1), (2), (3), or (4).

4. The apparatus of claim 1, wherein the central controller pre-reserves the MAC resources for transmission of remaining control signals of the sequence prior to information for the remaining control signals being stored in the transmission buffer of the mobile terminal.

5. The apparatus of claim 1, wherein the central controller pre-reserves the MAC resource to avoid transmission of a separate message to request a MAC resource for the control signal.

6. The apparatus of claim 1, wherein the central controller notifies the mobile terminal that the central controller has pre-reserved the MAC resource.

7. The apparatus of claim 1, wherein the central controller temporarily pre-reserves the MAC resource.

8. The apparatus of claim 7, wherein the central controller pre-reserves the MAC resource for a predetermined time.

9. The apparatus of claim 8, wherein upon expiration of the predetermined time the central controller reverts to a non-pre-reservation allocation scheme.

10. The apparatus of claim 7, wherein the central controller pre-reserves the MAC resource until a predetermined state transition has occurred.

11. The apparatus of claim 10, wherein the central controller pre-reserves the MAC resource until the central controller receives a signal from which the central controller can conclude that the mobile terminal has successfully entered a predetermined state.

12. The apparatus of claim 1, wherein the central controller pre-reserves the MAC resource in each MAC frame.

13. The apparatus of claim 1, wherein the central controller pre-reserves the MAC resource in a number of MAC frames in accordance with a predetermined rule.

14. The apparatus of claim 13, wherein the predetermined rule is that the central controller pre-reserves the MAC resource in every second MAC frame.

15. The apparatus of claim 1, wherein the central controller also pre-reserves resources for user data to be used in transmitting user data between the central controller and the mobile terminal after the sequence is completed.

16. For use in a wireless local area network (LAN) comprising a central controller and a mobile terminal, a method comprising the steps of:

the mobile terminal sending a first control signal of a sequence of control signals to the central controller in conjunction with an association operation;

upon receipt of the first control signal, the central controller pre-reserving a MAC resource for transmission of at least a further control signal in the sequence prior to information for the further control signal being stored in a transmission buffer of the mobile terminal.

17. The method of claim 16, further comprising the central controller anticipating eventuality of the further control signal and pre-reserving the MAC resource.

18. The method of claim 16, wherein the MAC resource which is pre-reserved by the central controller includes one of:

(1) an uplink Dedicated Control Channel (DCCH) Long Channel (LCH);

(2) an uplink Dedicated Control Channel (DCCH) Short Channel (SCH);

(3) a downlink Dedicated Control Channel (DCCH) Long Channel (LCH);

(4) a downlink Dedicated Control Channel (DCCH) Short Channel (SCH); and

(5) a combination of (1), (2), (3), or (4).

19. The method of claim 16, further comprising the central controller pre-reserving the MAC resources for transmission of remaining control signals of the sequence prior to information for the remaining control signals being stored in the transmission buffer of the mobile terminal.

20. The method of claim 16, further comprising the central controller pre-reserving the MAC resource to avoid transmission of a separate message to request a MAC resource for the further control signal.

21. The method of claim 16, further comprising the central controller notifying the mobile terminal that the central controller has pre-reserved the MAC resource.

22. The method of claim 16, further comprising the central controller temporarily pre-reserving the MAC resource.

23. The method of claim 22, further comprising the central controller pre-reserves the MAC resource for a predetermined time.

24. The method of claim 23, further comprising, upon expiration of the predetermined time, the central controller reverting to a non-pre-reservation allocation scheme.

25. The method of claim 22, further comprising the central controller pre-reserving the MAC resource until a predetermined state transition has occurred.

26. The method of claim 25, further comprising the central controller pre-reserving the MAC resource until the central controller receives a signal from which the central controller can conclude that the mobile terminal has successfully entered a predetermined state.

27. The method of claim 16, further comprising the central controller pre-reserving the MAC resource in each MAC frame.

28. The method of claim 16, further comprising the central controller pre-reserving the MAC resource in a number of MAC frames in accordance with a predetermined rule.

29. The method of claim 28, wherein the predetermined rule is that the central controller pre-reserves the MAC resource in every second MAC frame.

30. The method of claim 16, further comprising the central controller also pre-reserving resources for user data to be used in transmitting user data between the central controller and the mobile terminal after the sequence is completed.

31. A central controller of a wireless local area network (LAN) which, in conjunction with an association operation with a mobile terminal and upon receiving from the mobile terminal a first control signal of a sequence of control signals, pre-reserves a MAC resource for transmission of at least a further control signal in the sequence prior to information for the further control signal being stored in a transmission buffer of the mobile terminal.

32. The apparatus of claim 31, wherein the central controller anticipates eventuality of the further control signal and pre-reserves the MAC resource.

33. The apparatus of claim 31, wherein the MAC resource which is pre-reserved by the central controller includes one of:

(1) an uplink Dedicated Control Channel (DCCH) Long Channel (LCH);

(2) an uplink Dedicated Control Channel (DCCH) Short Channel (SCH);

(3) a downlink Dedicated Control Channel (DCCH) Long Channel (LCH);

(4) a downlink Dedicated Control Channel (DCCH) Short Channel (SCH); and

(5) a combination of (1), (2), (3), or (4).

34. The apparatus of claim 31, wherein the central controller pre-reserves the MAC resources for transmission of remaining control signals of the sequence prior to information for the remaining control signals being stored in the transmission buffer of the mobile terminal.

35. The apparatus of claim 31, wherein the central controller pre-reserves the MAC resource to avoid transmission of a separate message to request a MAC resource for the further control signal.

36. The apparatus of claim 31, wherein the central controller notifies the mobile terminal that the central controller has pre-reserved the MAC resource.

37. The apparatus of claim 31, wherein the central controller temporarily pre-reserves the MAC resource.

38. The apparatus of claim 37, wherein the central controller pre-reserves the MAC resource for a predetermined time.

39. The apparatus of claim 38, wherein upon expiration of the predetermined time the central controller reverts to a non-pre-reservation allocation scheme.

40. The apparatus of claim 37, wherein the central controller pre-reserves the MAC resource until a predetermined state transition has occurred.

41. The apparatus of claim 40, wherein the central controller pre-reserves the MAC resource until the central controller receives a signal from which the central controller can conclude that the mobile terminal has successfully entered a predetermined state.

42. The apparatus of claim 31, wherein the central controller pre-reserves the MAC resource in each MAC frame.

43. The apparatus of claim 31, wherein the central controller pre-reserves the MAC resource in a number of MAC frames in accordance with a predetermined rule.

44. The apparatus of claim 43, wherein the predetermined rule is that the central controller pre-reserves the MAC resource in every second MAC frame.

45. The apparatus of claim 31, wherein the central controller also pre-reserves resources for user data to be used in transmitting user data between the central controller and the mobile terminal after the sequence is completed.