DISCONTINUOUS RECEPTION TIMER OPERATION FOR CHANGED TTI LENGTH

• US 20190045440A1
• Filed: 02/03/2016
• Published: 02/07/2019
• Est. Priority Date: 02/03/2016
• Status: Active Grant

• Current Assignee: Nokia Technologies Oy (Nokia Corporation)
• Original Assignee: Nokia Technologies Oy (Nokia Corporation)
• Inventors: WU, Chunli, SEBIRE, Benoist Pierre
• Granted Patent: US 10,999,801 B2
• Time in Patent Office: Days
• 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 52/0219 where the power saving management affects multiple terminals
• CPC Class Codes: H04W 52/0222 in packet switched networks
• CPC Class Codes: H04W 52/0225 using monitoring of external events, e.g. the presence of a signal
• CPC Class Codes: H04W 52/0251 using monitoring of local events, e.g. events related to user activity
• CPC Class Codes: H04W 52/0258 controlling an operation mode according to history or models of usage information, e.g. activity schedule or time of day
• CPC Class Codes: H04W 76/28 Discontinuous transmission [DTX]; Discontinuous reception [DRX]
• CPC Class Codes: Y02D 30/70 in wireless communication networks

Abstract

While a transmission time interval (TTI) length of other than 1 ms is in effect for communication between mobile and network nodes, at least one timer related to discontinuous reception (DRX) is implemented according to a rule that defines a time duration of the timer different from a time duration of the same timer implemented when the TTI length is defined as 1 ms. There are a plurality of such DRX-related timers, and in certain embodiments each is associated with one rule of a set of rules for implementing the respective timer when the TTI length is other than 1 ms; and in particular examples the timers are associated with groups for this purpose and all the timers of at least one of the groups is implemented according to the same rule of the set. Thus new DRX parameters need not be sent anytime the TTI length changes.

Claims

1-25. -25. (canceled)

26. A method comprising:

determining that a transmission time interval length for communication between a mobile node and a network node is changed; and

while said changed transmission time interval length is in effect, implementing at least one timer related to discontinuous reception (DRX) according to a rule that defines a time duration of the timer different from a time duration of the same timer implemented when the unchanged transmission time interval length is in effect.

27. The method according to claim 26, wherein there is a plurality of timers related to DRX, and at least one other timer of the plurality of timers related to DRX defines a time duration that remains unchanged despite the changed transmission time interval length.

28. The method according to claim 27, wherein each timer of the plurality of timers related to DRX is associated with one rule of a set of rules, and each said timer is implemented according to its associated rule while said changed transmission time interval length is in effect.

29. The method according to claim 26, wherein the at least one timer is operated as one of:

the at least one timer is reset when the transmission time interval length is changed;

or

the at least one timer which is running continues to be running but unit is scaled according to said changed transmission time interval length.

30. The method according to claim 26, wherein said changed transmission time interval length is in effect comprises said changed transmission time interval length is configured via one of RRC signaling, and/or activated via MAC or PDCCH signaling.

31. The method according to claim 26, wherein there is a plurality of timers related to DRX, each said timer is implemented according to one rule of a set of rules that define a time duration of the respective timer while said changed transmission time interval length is in effect, and the set of rules comprises:

define a new sub-PDCCH subframe which refers to said changed transmission time interval length, and count the timer in number of said changed transmission time intervals with PDCCH;

define a new sub-subframe with said changed transmission time interval length and scale the timer to said changed transmission time interval length; and

keep the timer duration unchanged regardless of the transmission time interval length.

32. A non-transitory computer readable memory storing computer program instructions that, when executed by one or more processors, cause a user equipment or base station in which the memory and the one or more processors are disposed to:

determining that a transmission time interval length for communication between a mobile node and a network node is changed; and

while said changed transmission time interval length is in effect, implementing at least one timer related to discontinuous reception (DRX) according to a rule that defines a time duration of the timer different from a time duration of the same timer implemented when the unchanged transmission time interval length is in effect.

33. An apparatus comprising at least one processor and a memory storing software code;

wherein the memory and the software code is configured with the at least one processor to cause the apparatus to at least;

determine that a transmission time interval length for communication between a mobile node and a network node is changed; and

while said changed transmission time interval length is in effect, implement at least one timer related to discontinuous reception (DRX) according to a rule that defines a time duration of the timer different from a time duration of the same timer implemented when the unchanged transmission time interval length is in effect.

34. The apparatus according to claim 33, wherein there is a plurality of timers related to DRX, and at least one other timer of the plurality of timers related to DRX defines a time duration that remains unchanged despite the changed transmission time interval length is in effect.

35. The apparatus according to claim 34, wherein each timer of the plurality of timers related to DRX is associated in the memory with one rule of a set of rules, and each said timer is implemented according to its associated rule while said changed transmission time interval length is in effect.

36. The apparatus according to claim 33, wherein the at least one timer is operated as one of:

the at least one timer is reset when the transmission time interval length is changed;

or

the at least one timer which is running continue to be running but unit is scaled according to the transmission time interval length.

37. The apparatus according to claim 33, wherein said changed transmission time interval length is in effect comprises said changed transmission time interval length is configured via one of radio resource control (RRC) signaling, and/or activated via medium access control (MAC) or physical downlink control channel (PDCCH) signaling.

38. The apparatus according to claim 33, wherein there is a plurality of timers related to DRX, each said timer is implemented according to one rule of a set of rules that define a time duration of the respective timer while said changed transmission time interval length is in effect, and the set of rules comprises:

define a new sub-PDCCH subframe which refer to said changed transmission time interval length, and count the timer in number of said changed transmission time intervals with PDCCH;

define a new sub-subframe with said changed transmission time interval length and scale the timer to said changed transmission time interval length; and

keep the timer duration unchanged regardless of the transmission time interval length.

39. The apparatus according to claim 38, wherein the memory and the software code is configured with the at least one processor to cause the apparatus further to:

for each respective timer other than a DRX cycle timer that is associated with the rule “

keep the timer duration unchanged regardless of the transmission time interval length”

, restart the respective timer if a PDCCH is received while the respective timer is running and said changed transmission time interval length is in effect.

40. The apparatus according to claim 35, wherein:

network signaling and/or a published radio technology standard associates each of the plurality of timers related to DRX with its associated one rule of the set of rules.

41. The apparatus according to claim 33, wherein the at least one timer is a hybrid automatic repeat request round trip time timer, and the rule is to scale the timer according to said changed transmission time interval length.

42. The apparatus according to claim 33, wherein there is a plurality of timers related to DRX and each of the plurality of timers are associated with either a first group or a second group for implementing each said timer while the changed transmission time interval length is in effect.

43. The apparatus according to claim 42, wherein:

the timers associated with the second group include at least;

an on duration timer,

a discontinuous reception inactivity timer, and

a discontinuous reception retransmission timer;

and the timers associated with the first group include at least;

a contention resolution timer,

a discontinuous reception cycle timer,

a discontinuous reception short cycle timer, and

a hybrid automatic repeat request round trip time timer.

44. The apparatus according to claim 33, wherein the memory and the software code is configured with the at least one processor to cause the apparatus further to start an on duration timer in a first or a second half of an offset subframe according to a value of a signaled bit, wherein the offset subframe is identified by a DRX start offset timer when the unchanged transmission time interval length is in effect.

45. The apparatus according to claim 33, wherein the apparatus comprises the mobile node which is embodied as a user equipment, or the apparatus comprises the network node which is embodied as a base station.