1. A method of communication comprising: determining, at a terminal device served by a first network device, that uplink transmission is to be performed with a second network device serving the terminal device; 5 and transmitting, to the first network device, a request to activate a cell group of the second network device, the request comprising characteristic information concerning the uplink transmission. 10 2. The method of claim 1, wherein the characteristic information comprises at least one of: a cause triggering the uplink transmission, or an identification of a data session associated with the uplink transmission. 15 3. The method of claim 1, wherein transmitting the request comprises: determining whether a timer for activation of the cell group is running; and in accordance with a determination that the timer is not running, transmitting the request. 20 4. The method of claim 3, further comprising: in response to transmitting the request, starting the timer.

5. The method of claim 3, further comprising: receiving, from the first network device or the second network device, an upper 25 value for the timer along with an indication to deactivate the cell group.

6. A method of communication comprising: receiving, at a first network device from a terminal device, a request to activate a cell group of a second network device, the terminal device served by the first network 30 device and the second network device; determining, from the request, characteristic information concerning uplink transmission to be performed with the second network device; and causing the uplink transmission to be performed based on the characteristic 34 information.

7. A method of communication comprising: determining, at a terminal device served by a first network device, that uplink 5 transmission is to be performed with a second network device serving the terminal device; enabling transmission on a primary cell of a cell group of the second network device; transmitting, to the second network device on the primary cell, a first request to activate the cell group of the second network device; and 10 monitoring a response to the first request based on a first timer for activation of the cell group.

8. The method of claim 7, further comprising: in accordance with a determination that the first timer expires, transmitting to the 15 first network device at least one of: a message indicating a failure in activating the cell group of the second network device, or a second request to activate the cell group of the second network device. 20 9. The method of claim 7, wherein the first request comprises a random access request for a random access procedure, and the method further comprises: in accordance with a determination that the random access procedure is successful, stopping the first timer. 25 10. The method of claim 7, wherein the first request comprises a radio resource control (RRC) message, and transmitting the first request comprises: resuming a signaling radio bearer on the cell group; and transmitting the RRC message by using the signaling radio bearer. 30 11. The method of claim 10, further comprises: receiving a first response to the first request from the second network device, the first response indicating that activating the cell group is allowed; and in response to receiving the first response, stopping the first timer; 35 resuming a further signaling radio bearer on the cell group and data radio bearers on the cell group; and enabling transmission on one or more secondary cell of the cell group.

TECHNICAL FIELD
5 [0001] Embodiments of the present disclosure generally relate to the field of
telecommunication, and in particular, to methods, devices, and medium for communication.
BACKGROUND
[0002] Dual Connectivity is a mode of operation where a terminal device (for example,
10 user equipment, UE) can be configured to utilize radio resources provided by two network
devices (for example, two base stations). A first network device serves the terminal
device as a Master Node (MN), and a second network device serves the terminal device as a
Secondary Node (SN). The MN and SN are connected via a non-ideal back-haul over a
network interface and at least the MN is connected to a core network (CN).
15 [0003] The MN and SN may be associated with one or more serving cells. In a carrier
aggregation (CA) scenario, each of the MN and SN may be associated with a group of
serving cells including a primary cell (PCell) and optionally one or more secondary cells
(SCells). The group of serving cells associated with the MN is referred to as a Master Cell
Group (MCG) and the group of serving cells associated with the SN is referred to as a
20 Secondary Cell Group (SCG). In some cases, the SCG may be suspended to reduce power
consumption for example. The suspended SCG may need to be resumed due to uplink
data arrival. However, mechanism of SCG resumption has not be specified.
SUMMARY
25 [0004] In general, example embodiments of the present disclosure provide a solution for
SCG resumption.
[0005] In a first aspect, there is provided a method of communication. The method
comprises determining, at a terminal device served by a first network device, that uplink
transmission is to be performed with a second network device serving the terminal device;
30 and transmitting, to the first network device, a request to activate a cell group of the second
network device, the request comprising characteristic information concerning the uplink
transmission.
3
[0006] In a second aspect, there is provided a method of communication. The method
comprises receiving, at a first network device from a terminal device, a request to activate a
cell group of a second network device, the terminal device served by the first network
device and the second network device; determining, from the request, characteristic
5 information concerning uplink transmission to be performed with the second network
device; and causing the uplink transmission to be performed based on the characteristic
information.
[0007] In a third aspect, there is provided a method of communication. The method
comprises determining, at a terminal device served by a first network device, that uplink
10 transmission is to be performed with a second network device serving the terminal device;
enabling transmission on a primary cell of a cell group of the second network device;
transmitting, to the second network device on the primary cell, a first request to activate the
cell group of the second network device; and monitoring a response to the first request
based on a first timer for activation of the cell group.
15 [0008] In a fourth aspect, there is provided a terminal device. The network device
includes a processing unit; and a memory coupled to the processing unit and storing
instructions thereon, the instructions, when executed by the processing unit, causing the
device to perform the method according to the first aspect.
[0009] In a fifth aspect, there is provided a network device. The network device includes
20 a processing unit; and a memory coupled to the processing unit and storing instructions
thereon, the instructions, when executed by the processing unit, causing the device to
perform the method according to the second aspect.
[0010] In a sixth aspect, there is provided a terminal device. The terminal device
includes a processing unit; and a memory coupled to the processing unit and storing
25 instructions thereon, the instructions, when executed by the processing unit, causing the
device to perform the method according to the third aspect.
[0011] In a seventh aspect, there is provided a computer readable medium having
instructions stored thereon, the instructions, when executed on at least one processor,
causing the at least one processor to carry out the method according to the first aspect.
30 [0012] In an eighth aspect, there is provided a computer readable medium having
instructions stored thereon, the instructions, when executed on at least one processor,
causing the at least one processor to carry out the method according to the second aspect.
4
[0013] In a ninth aspect, there is provided a computer readable medium having
instructions stored thereon, the instructions, when executed on at least one processor,
causing the at least one processor to carry out the method according to the third aspect.
[0014] Other features of the present disclosure will become easily comprehensible
5 through the following description.
BRIEF DESCRIPTION OF THE DRAWINGS
[0015] Through the more detailed description of some example embodiments of the
present disclosure in the accompanying drawings, the above and other objects, features and
10 advantages of the present disclosure will become more apparent, wherein:
[0016] Fig. 1 is a block diagram of a communication environment in which embodiments
of the present disclosure can be implemented;
[0017] Fig. 2 is a signaling chart illustrating process of requesting to the MN for SCG
resumption according to some embodiments of the present disclosure;
15 [0018] Fig. 3 is a signaling chart illustrating process of requesting to the SN for SCG
resumption according to some embodiments of the present disclosure;
[0019] Fig. 4 is a signaling chart illustrating process of requesting to the SN for SCG
resumption according to some embodiments of the present disclosure;
[0020] Fig. 5 illustrates an example method of communication implemented at a terminal
20 device in accordance with some embodiments of the present disclosure;
[0021] Fig. 6 illustrates an example method of communication implemented at a network
device in accordance with some embodiments of the present disclosure;
[0022] Fig. 7 illustrates an example method of communication implemented at a terminal
device in accordance with some embodiments of the present disclosure; and
25 [0023] Fig. 8 is a simplified block diagram of a device that is suitable for implementing
embodiments of the present disclosure.
[0024] Throughout the drawings, the same or similar reference numerals represent the
same or similar element.

WE CLAIM:
1. A method of communication comprising:
determining, at a terminal device served by a first network device, that uplink
transmission is to be performed with a second network device serving the terminal device;
5 and
transmitting, to the first network device, a request to activate a cell group of the
second network device, the request comprising characteristic information concerning the
uplink transmission.
10 2. The method of claim 1, wherein the characteristic information comprises at
least one of:
a cause triggering the uplink transmission, or
an identification of a data session associated with the uplink transmission.
15 3. The method of claim 1, wherein transmitting the request comprises:
determining whether a timer for activation of the cell group is running; and
in accordance with a determination that the timer is not running, transmitting the
request.
20 4. The method of claim 3, further comprising:
in response to transmitting the request, starting the timer.
5. The method of claim 3, further comprising:
receiving, from the first network device or the second network device, an upper
25 value for the timer along with an indication to deactivate the cell group.
6. A method of communication comprising:
receiving, at a first network device from a terminal device, a request to activate a
cell group of a second network device, the terminal device served by the first network
30 device and the second network device;
determining, from the request, characteristic information concerning uplink
transmission to be performed with the second network device; and
causing the uplink transmission to be performed based on the characteristic
34
information.
7. A method of communication comprising:
determining, at a terminal device served by a first network device, that uplink
5 transmission is to be performed with a second network device serving the terminal device;
enabling transmission on a primary cell of a cell group of the second network
device;
transmitting, to the second network device on the primary cell, a first request to
activate the cell group of the second network device; and
10 monitoring a response to the first request based on a first timer for activation of the
cell group.
8. The method of claim 7, further comprising:
in accordance with a determination that the first timer expires, transmitting to the
15 first network device at least one of:
a message indicating a failure in activating the cell group of the second network
device, or
a second request to activate the cell group of the second network device.
20 9. The method of claim 7, wherein the first request comprises a random access
request for a random access procedure, and the method further comprises:
in accordance with a determination that the random access procedure is successful,
stopping the first timer.
25 10. The method of claim 7, wherein the first request comprises a radio resource
control (RRC) message, and transmitting the first request comprises:
resuming a signaling radio bearer on the cell group; and
transmitting the RRC message by using the signaling radio bearer.
30 11. The method of claim 10, further comprises:
receiving a first response to the first request from the second network device, the
first response indicating that activating the cell group is allowed; and
in response to receiving the first response,
stopping the first timer;
35
resuming a further signaling radio bearer on the cell group and data radio bearers on
the cell group; and
enabling transmission on one or more secondary cell of the cell group.