Implicit DRX cycle length adjustment control in LTE_active mode

• US 10,237,820 B2
• Filed: 07/20/2017
• Issued: 03/19/2019
• Est. Priority Date: 01/30/2007
• Status: Active Grant

• Current Assignee: Interdigital Technology Corporation (InterDigital, Inc.)
• Original Assignee: Interdigital Technology Corporation (InterDigital, Inc.)
• Inventors: Terry, Stephen E., Wang, Peter S., Wang, Jin
• Primary Examiner(s): Harper, Kevin C.
• Assistant Examiner(s): Davenport, Mon Cheri S
• Application Number:
  US15/655,510
• Publication Number:
  US 20170318533A1
• Time in Patent Office: 607 Days
• Field of Search: 370311, 370252, 370329, 370338, 455574, 455445, 455450, 455436, 455420, 455502, 4553432
• CPC Class Codes: H04W 52/0212 managed by the network, e.g. network or access point is master and terminal is slave
• CPC Class Codes: H04W 52/0216 using a pre-established activity schedule, e.g. traffic indication frame
• CPC Class Codes: H04W 52/0229 where the received signal is a wanted signal
• CPC Class Codes: H04W 52/0235 where the received signal is a power saving command
• CPC Class Codes: H04W 76/28 Discontinuous transmission [DTX]; Discontinuous reception [DRX]
• CPC Class Codes: Y02D 30/70 in wireless communication networks

Abstract

A method for controlling discontinuous reception in a wireless transmit/receive unit includes defining a plurality of DRX levels, wherein each DRX level includes a respective DRX cycle length and transitioning between DRX levels based on a set of criteria. The transitioning may be triggered by implicit rules.

Claims

1. A method implemented by a wireless transmit/receive unit (WTRU), the method comprising:

the WTRU receiving a discontinuous reception (DRX) configuration in a radio resource control (RRC) message, the DRX configuration comprising a first DRX cycle length, a second DRX cycle length, and a value for a WTRU timer used to trigger a transition from the first DRX cycle length to the second DRX cycle length, wherein the second DRX cycle length is a multiple of the first DRX cycle length;

the WTRU performing DRX using the second DRX cycle length;

the WTRU receiving a trigger from a base station;

the WTRU performing DRX using the first DRX cycle length based on receiving the trigger;

the WTRU starting the WTRU timer upon beginning DRX operation using the first DRX cycle length;

the WTRU determining that the WTRU timer has expired; and

the WTRU transitioning from the first DRX cycle length to the second DRX cycle length in response to the WTRU determining that the WTRU timer has expired.

2. The method as in claim 1, wherein the second DRX cycle length is an integer power of two of the first DRX cycle length.

3. The method as in claim 2, wherein the first and second DRX cycle lengths are selected from a set of DRX cycle lengths given by the equation DRX-cycle-len=L×

2ⁿ where n=0, 1, 2, . . . and L is the first DRX cycle length.

4. The method as in claim 1, wherein the WTRU timer is synchronized with a base station timer.

5. The method as in claim 1, wherein the WTRU timer is implemented as a counter.

6. The method as in claim 1, wherein the value of the WTRU timer is signaled as a number of DRX cycles.

19. The method as in claim 1, further comprising:

the WTRU receiving a second trigger from the base station, the second trigger indicating that the WTRU should perform DRX using the second DRX cycle length; and

the WTRU performing DRX using the second DRX cycle length based on receiving the second trigger.

7. A wireless transmit/receive unit (WTRU) comprising a processor and memory configured to:

receive a discontinuous reception (DRX) configuration in a radio resource control (RRC) message, the DRX configuration comprising a first DRX cycle length, a second DRX cycle length, and a value for a WTRU timer used to trigger a transition from the first DRX cycle length to the second DRX cycle length;

perform DRX using the second DRX cycle length;

receive a trigger from a base station;

perform DRX using the first DRX cycle length based on receiving the trigger;

start the WTRU timer upon beginning DRX operation using the first DRX cycle length;

determine that the WTRU timer has expired; and

transition from the first DRX cycle length to the second DRX cycle length in response to the expiration of the WTRU timer, wherein the second DRX cycle length is a multiple of the first DRX cycle length.

8. The WTRU as in claim 7, wherein the second DRX cycle length is an integer power of two of the first DRX cycle length.

9. The WTRU as in claim 8, wherein the first and second DRX cycle lengths are selected from a set of DRX cycle lengths given by the equation DRX-cycle-len=L×

2ⁿ where n=0, 1, 2, . . . and L is the first DRX cycle length.

10. The WTRU as in claim 7, wherein the WTRU timer is synchronized with a base station timer.

11. The WTRU as in claim 7, wherein the WTRU timer is implemented as a counter.

12. The WTRU as in claim 7, wherein the value of the WTRU timer is signaled as a number of DRX cycles.

20. The WTRU as in claim 7, wherein the processor and memory are further configured to:

receive a second trigger from the base station, the second trigger indicating that the WTRU should perform DRX using the second DRX cycle length; and

perform DRX using the second DRX cycle length based on receiving the second trigger.

13. A wireless transmit/receive unit (WTRU) comprising a processor and memory configured to:

receive a discontinuous reception (DRX) configuration in a radio resource control (RRC) message, the DRX configuration comprising a first DRX cycle length, a second DRX cycle length, and a value for a WTRU timer used to trigger a transition from the first DRX cycle length to the second DRX cycle length;

receive a first trigger from a base station, the first trigger indicating that the WTRU should perform DRX using the second DRX cycle length;

perform DRX using the second DRX cycle length based on receiving the first trigger;

receive a second trigger from the base station, the second trigger indicating that the WTRU should perform DRX using the first DRX cycle length;

perform DRX using the first DRX cycle length based on receiving the second trigger;

start the WTRU timer upon beginning DRX operation using the first DRX cycle length;

determine that the WTRU timer has expired; and

transition from the first DRX cycle length to the second DRX cycle length in response to the expiration of the WTRU timer, wherein the second DRX cycle length is a multiple of the first DRX cycle length.

14. The WTRU as in claim 13, wherein the second DRX cycle length is an integer power of two of the first DRX cycle length.

15. The WTRU as in claim 14, wherein the first and second DRX cycle lengths are selected from a set of DRX cycle lengths given by the equation DRX-cycle-len=L×

2ⁿ where n=0, 1, 2, . . . and L is the first DRX cycle length.

16. The WTRU as in claim 13, wherein the WTRU timer is synchronized with a base station timer.

17. The WTRU as in claim 13, wherein the WTRU timer is implemented as a counter.

18. The WTRU as in claim 13, wherein the value of the WTRU timer is signaled as a number of DRX cycles.