TECHNICAL FIELD
5 [0001] Embodiments of the present disclosure generally relate to the field of
telecommunication, and in particular, to methods, devices and computer storage media of
communication during a switch among communication networks.
BACKGROUND
10 [0002] Currently, a multi-universal subscriber identity module (USIM) terminal device
occupies a large market share. Two USIM cards may conform to same or different
communication standards such as long term evolution (LTE), new radio (NR) or the like,
and the radio frequency (RF) capability of the terminal device may be 1 transmit port (Tx) I
1 receive port (Rx), 1 Tx/2Rx, 2Tx/2Rx or the like. However, no specification
15 enhancement is made to improve the performance of the multi-USIM terminal device.
[0003] Assuming that a multi-USIM terminal device with single Tx registers to more than
one network, e.g. a network (also referred to as a first network below) of USIM A and a
network(also referred to as a second network below) of USIM B, and the terminal device
has established a connection in the first network but stayed in idle or inactive state in the
20 second network. Currently, when the terminal device needs to perform data transmission
in the second network, the terminal device just releases the connection with the first
network without notifying the first network. In this case, the first network would consider
the terminal device as connection failure, which lead to incorrect network performance
recording. Thus, the performance of the multi-USIM terminal device would not be
25 assured.
SUMMARY
[0004] In general, embodiments of the present disclosure provide methods, devices and
computer storage media for communication.
30 [0005] In a first aspect, there is provided a method of communication. The method
comprises: determining, at a terminal device, whether a switch is to be performed from a
first network device of a first communication network to a second network device of a
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second communication network, the first and second communication networks being
associated with first and second identities of the terminal device respectively; and in
response to determining that the switch is to be performed, transmitting, to the first network
device, a request for the switch from the first network device to the second network device.
5 [0006] In a second aspect, there is provided a method of communication. The method
comprises: receiving, at a first network device of a first communication network and from a
terminal device, a request for a switch from the first network device to a second network
device of a second communication network, the first and second communication networks
being associated with first and second identities of the terminal device respectively.
10 [0007] In a third aspect, there is provided a terminal device. The terminal device
comprises a processor and a memory coupled to the processor. The memory stores
instructions that when executed by the processor, cause the terminal device to perform the
method according to the first aspect of the present disclosure.
[0008] In a fourth aspect, there is provided a network device. The network device
15 comprises a processor and a memory coupled to the processor. The memory stores
instructions that when executed by the processor, cause the network device to perform the
method according to the second aspect of the present disclosure.
[0009] In a fifth aspect, there is provided a computer readable medium having instructions
stored thereon. The instructions, when executed on at least one processor, cause the at
20 least one processor to perform the method according to the first aspect of the present
disclosure.
[0010] In a sixth aspect, there is provided a computer readable medium having
instructions stored thereon. The instructions, when executed on at least one processor,
cause the at least one processor to perform the method according to the second aspect of the
25 present disclosure.
[0011] Other features of the present disclosure will become easily comprehensible
through the following description.
BRIEF DESCRIPTION OF THE DRAWINGS
30 [0012] Through the more detailed description of some embodiments of the present
disclosure in the accompanying drawings, the above and other objects, features and
advantages of the present disclosure will become more apparent, wherein:
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[0013] FIG. 1 illustrates an example communication scenario m which some
embodiments of the present disclosure can be implemented;
[0014] FIG. 2 illustrates a schematic diagram illustrating a process for communication
during a switch from a first network to a second network according to some embodiments
5 of the present disclosure;
[0015] FIG. 3 illustrates an example method of communication implemented at a terminal
device in accordance with some embodiments of the present disclosure;
[0016] FIG. 4 illustrates another example method of communication implemented at a
terminal device in accordance with some embodiments of the present disclosure;
10 [0017] FIG. 5 illustrates another example method of communication implemented at a
terminal device in accordance with some embodiments of the present disclosure;
[0018] FIG. 6 illustrates another example method of communication implemented at a
terminal device in accordance with some embodiments of the present disclosure;
[0019] FIG. 7 illustrates another example method of communication implemented at a
15 terminal device in accordance with some embodiments of the present disclosure;
[0020] FIG. 8 illustrates an example method of communication implemented at a network
device in accordance with some embodiments of the present disclosure;
[0021] FIG. 9 illustrates another example method of communication implemented at a
network device in accordance with some embodiments of the present disclosure;
20 [0022] FIG. 10 illustrates another example method of communication implemented at a
network device in accordance with some embodiments of the present disclosure; and
[0023] FIG. 11 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
25 same or similar element.
DETAILED DESCRIPTION
[0025] Principle of the present disclosure will now be described with reference to some
embodiments. It is to be understood that these embodiments are described only for the
30 purpose of illustration and help those skilled in the art to understand and implement the
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present disclosure, without suggesting any limitations as to the scope of the disclosure.
The disclosure described herein can be implemented in various manners other than the ones
described below.
[0026] In the following description and claims, unless defined otherwise, all technical and
5 scientific terms used herein have the same meaning as commonly understood by one of
ordinary skills in the art to which this disclosure belongs.
[0027] As used herein, the term "terminal device" refers to any device having wireless or
wired communication capabilities. Examples of the terminal device include, but not
limited to, user equipment (UE), personal computers, desktops, mobile phones, cellular
10 phones, smart phones, personal digital assistants (PDAs), portable computers, tablets,
wearable devices, internet of things (loT) devices, Internet of Everything (IoE) devices,
machine type communication (MTC) devices, device on vehicle for V2X communication
where X means pedestrian, vehicle, or infrastructure/network, or image capture devices
such as digital cameras, gaming devices, music storage and playback appliances, or Internet
15 appliances enabling wireless or wired Internet access and browsing and the like. The term
"terminal device" can be used interchangeably with a UE, a mobile station, a subscriber
station, a mobile terminal, a user terminal or a wireless device. In addition, the term
"network device" refers to a device which is capable of providing or hosting a cell or
coverage where terminal devices can communicate. Examples of a network device
20 include, but not limited to, a Node B (NodeB or NB), an evolved NodeB (eNodeB or eNB),
a next generation NodeB (gNB), a transmission reception point (TRP), a remote radio unit
(RRU), a radio head (RH), a remote radio head (RRH), a low power node such as a femto
node, a pica node, and the like.
[0028] In one embodiment, the terminal device may be connected with a first network
25 device and a second network device. One of the first network device and the second
network device may be a master node and the other one may be a secondary node. The
first network device and the second network device may use different RATs. In one
embodiment, the first network device may be a first RAT device and the second network
30
device may be a second RAT device.
the second RAT device is gNB.
In one embodiment, the first RAT device is eNB and
Information related with different RATs may be
transmitted to the terminal device from at least one of the first network device and the
second network device. In one embodiment, first information may be transmitted to the
terminal device from the first network device and second information may be transmitted to
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the terminal device from the second network device directly or via the first network device.
In one embodiment, information related with configuration for the terminal device
configured by the second network device may be transmitted from the second network
device via the first network device. Information related with reconfiguration for the
5 terminal device configured by the second network device may be transmitted to the
terminal device from the second network device directly or via the first network device.
[0029] As used herein, the singular forms 'a', 'an' and 'the' are intended to include the
plural forms as well, unless the context clearly indicates otherwise. The term 'includes'
and its variants are to be read as open terms that mean 'includes, but is not limited to.'
10 The term 'based on' is to be read as 'at least in part based on.' The term 'one embodiment'
and 'an embodiment' are to be read as 'at least one embodiment.' The term 'another
embodiment' is to be read as 'at least one other embodiment.' The terms 'first,' 'second,'
and the like may refer to different or same objects. Other definitions, explicit and implicit,
may be included below.
15 [0030] In some examples, values, procedures, or apparatus are referred to as 'best,'
'lowest,' 'highest,' 'minimum,' 'maximum,' or the like. It will be appreciated that such
descriptions are intended to indicate that a selection among many used functional
alternatives can be made, and such selections need not be better, smaller, higher, or
otherwise preferable to other selections.
20 [0031] As mentioned above, currently, when the terminal device needs to perform data
transmission in the second network, the terminal device just releases the connection with
the first network without notifying the first network. In this case, the first network would
consider the terminal device as connection failure, which lead to incorrect network
performance recording.
25 [0032] Embodiments of the present disclosure provide a solution for notifying a switch
from the first network to the second network so as to solve the above and other problems.
The solution can avoid incorrect network performance recording and facilitate enhancement
of the performance of the terminal device. Principles and implementations of the present
disclosure will be described in detail below with reference to the figures.
30 [0033] FIG. 1 illustrates a schematic diagram of an example communication scenario 100
in which embodiments of the present disclosure can be implemented. As shown in FIG. 1,
the communication scenario 100 may involve a network device 110 (also referred to as a
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first network device 110 hereafter) and a terminal device 120 carrying a first USIM card
121 and a second USIM card 122. The first network device 110 may serve at least one of
the first and second USIM cards 121 and 122. The first and second USIM cards 121 and
122 may conform same or different RATs which are existing now or to be developed in the
5 future. It should be noted that the number of the USIM cards carried by the terminal
device 120 is not limited to two, and more than two USIM cards also can be applied. For
convenience, the following description is given by taking two USIM cards as an example.
[0034] As shown in FIG. 1, the communication scenario 100 may further involve at least
one neighboring network device 111 (also referred to as a second network device 111
10 hereafter). Here, only one second network device 111 is shown in FIG. 1 for concise.
The neighboring network device 111 may also serve at least one of the first and second
USIM cards 121 and 122. For convenience, unless otherwise stated, the following
description is made under the assumption that the first network device 110 serves the first
USIM card 121 and the second network device 111 serves the second USIM card 122.
15 However, it should be noted that, it is merely an example for illustration, and does not make
limitation for the present disclosure. For example, the first and second USIM cards 121
and 122 may be served by the same network device such as the first network device 110 or
the second network device 111.
[0035] Further, the first network device 110 may communicate with the terminal device
20 120 via a channel such as a wireless communication channel. Similarly, the second
network device 111 may also communicate with the terminal device 120 via a channel such
as a wireless communication channel.
[0036] It is to be understood that the number of devices in FIG. 1 is given for the purpose
of illustration without suggesting any limitations to the present disclosure. The
25 communication scenario 100 may involve any suitable number of network devices and/or
terminal devices adapted for implementing implementations of the present disclosure.
[0037] The communications in the communication scenario 100 may conform to any
suitable standards including, but not limited to, Global System for Mobile Communications
(GSM), Long Term Evolution (LTE), LTE-Evolution, LTE-Advanced (LTE-A), Wideband
30 Code Division Multiple Access (WCDMA), Code Division Multiple Access (CDMA),
GSM EDGE Radio Access Network (GERAN), Machine Type Communication (MTC) and
the like. Furthermore, the communications may be performed according to any generation
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communication protocols either currently known or to be developed in the future.
Examples of the communication protocols include, but not limited to, the first generation
(lG), the second generation (2G), 2.5G, 2.75G, the third generation (3G), the fourth
generation (4G), 4.5G, the fifth generation (5G) communication protocols, the sixth
5 generation (6G) communication protocols or beyond.
[0038] For convenience, the communication network formed between the first network
device 110 and the terminal device 120 is called as a first network (also referred to as a first
communication network below), and the communication network formed between the
second network device Ill and the terminal device 120 is called as a second network (also
10 referred to as a second communication network).
[0039] It should be noted that one terminal device may involve multiple networks in
multiple communication network systems. In some embodiments, the multiple networks
may be associated with multiple identities of the terminal device. It should be noted that
the multiple networks may be associated with other aspects of the terminal device, and the
15 present application does not make limitation for this. For illustration, the following
description is given by taking a first network and a second network associated with first and
second subscriber identity modules of a terminal device as an example.
[0040] As shown in FIG. 1, in case that the terminal device 120 has established a
connection with the first network device 110 in the first network and stayed in idle or
20 inactive state in the second network, if the terminal device 120 needs to perform data
transmission with the second network device 111 in the second network, the terminal
device 120 needs to perform a switch from the first network device 110 of the first network
to the second network device 111 of the second network.
[0041] According to embodiments of the present application, if determining that a switch
25 is to be performed from the first network device 110 to the second network device Ill, the
terminal device 120 transmits a request for the switch to the first network device 110. In
this way, the switch can be notified to the network device and thus incorrect network
performance recording can be avoided. More details will be described with reference to
FIG. 2.
30 [0042] FIG. 2 shows a schematic diagram illustrating a process 200 for communication
during a switch from a first network to a second network according to embodiments of the
present disclosure. For the purpose of discussion, the process 200 will be described with
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reference to FIG. 1. The process 200 may involve the terminal device 120, the first
network device 110 and the second network device 111 as illustrated in FIG. 1. In this
embodiment, the terminal device 120 is assumed to be in a connected state in the first
network of the first network device 110, and in an idle or inactive state in the second
5 network of the second network device 111.
[0043] As shown in FIG. 2, the terminal device 120 determines 210 whether a switch is to
be performed from the first network device 110 to the second network device 111. In
some embodiments, the terminal device 120 may determine whether data is to be
transmitted between the terminal device 120 and the second network device 111, and if
10 determining that the data is to be transmitted, the terminal device 120 may determine that
whether there is ongoing emergency service in the first network. If determining that there
is no ongoing emergency service in the first network, the terminal device 120 may
determine that the switch is to be performed.
[0044] For example, if the terminal device 120 has mobile originate (MO) data to be
15 transmitted to the second network device 111 and there is no ongoing emergency service in
the first network, the terminal device 120 may determine that the switch is to be performed.
Alternatively, if the terminal device 120 receives a paging message from the second
network device 111 and there is no ongoing emergency service in the first network, the
terminal device 120 may determine that the switch is to be performed. If determining
20 there is ongoing emergency service in the first network, the terminal device 120 shall
neglect the paging information to avoid interrupting the emergency service. In this way,
the quality of the emergency service is assured.
[0045] Upon determining that the switch is to be performed, the terminal device 120
transmits 220 a request for the switch to the first network device 110. In some
25 embodiments, the terminal device 120 may transmit the request via a radio resource control
(RRC) message. For example, the terminal device 120 may transmit the request via
UEAssistanceinformation message. It should be noted that any other existing or future
developed RRC messages can also be used, and the present application does not make
limitation for this.
30 [0046] In some embodiments, the request may comprise an expected RRC state in the first
communication network. For example, the expected RRC state may include an idle,
inactive or connected state. In some alternative or additional embodiments, the request
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may comprise a cause of the request. For example, the cause may include power saving
for power saving case. As another example, the cause may include network switch for the
switch to the second network case. It should be noted that any other suitable forms of the
cause are also feasible. In this way, it is useful for the first network device 110 to
5 differentiate the reason of releasing request.
[0047] In some embodiments in which the cause of the request includes the network
switch, the request may comprise service information of the second communication
network. In some embodiments, the service information may include expected switch
period or pattern of absent. For example, the service information may include expected
10 periodicity, time domain offset and absent time per cycle.
[0048] In some embodiments in which time-division multiplexing (TDM) pattern to be
used is decided by the terminal device 120, the request may include a suggestion of a TDM
pattern. In some embodiments, the request may include a list of candidate TDM patterns.
In this case, the first network device 110 may select one from the list. In some
15 embodiments, the suggestion of the TDM pattern may be transmitted in the request. For
example, the terminal device 120 may transmit the suggestion of the TDM pattern in the
request via UEAssistantinformation message. In some alternative embodiments, the
suggestion of the TDM pattern may be transmitted separately from the request. For
example, the terminal device 120 may transmit the suggestion of the TDM pattern via
20 RRCSetupComplete message.
[0049] According to embodiments of the present application, the TDM pattern (also
referred to as switch gap herein) is configured for the terminal device 120 to switch to the
second network for a certain period, e.g., for a short period to transmit small data, while
remaining connected state in the first network.
25 [0050] During off period of the TDM pattern, the first network device 110 should avoid
scheduling the terminal device 120, and the medium access control (MAC) entity of the
terminal device 120 shall, on all the Serving Cell(s) or specific Serving Cell(s) configured,
not perform any uplink (UL) transmission except for Msg 3 and Msg A, not perform
physical downlink control channel (PDCCH) monitoring and downlink (DL) reception
30 except if the random access response (RAR) window, msgB response window or the
Contention Resolution timer is running.
[0051] In some embodiments, the first network device 110 may broadcast whether it
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supports the TDM pattern in system information, and the terminal device 120 may
determine, from the system information, whether the first network device 110 supports the
TDM pattern. In accordance with a determination that the first network device 110
supports the TDM pattern, the terminal device 120 may determine a TDM pattern and
5 incorporate the TDM pattern in the request for the switch.
[0052] In some embodiments, the TDM pattern information may compnse starting
information and duration of the switch. This may be considered as one shot switch gap.
In some embodiments, the starting information may include any of system frame number
(SFN), time slot number, orthogonal frequency division multiplexing (OFDM) symbol
10 number. In some alternative embodiments, the TDM pattern information may comprise a
periodicity, a time domain offset and a length of absent time per cycle of the switch. This
may be considered as periodical switch gap.
[0053] It should be noted that the request are not limited by the above examples, but also
include any other suitable information associated with data transmission to be performed in
15 the second communication network. In this way, it is useful for the first network device
110 to decide on a TDM pattern to be used.
[0054] In some embodiments in which the terminal device 120 is configured with dual
connectivity (DC) and the terminal device 120 wants to remain connected state in the first
network, the request may include a release or deactivation of at least part of serving cells
20 while remaining a connected state in the first communication network. For example, the
terminal device 120 may set the expected RRC state as a connected state, and indicate
releasing or deactivating the entire secondary node (SN). Alternatively, the terminal
device 120 may set the expected RRC state as a connected state, and indicate releasing or
deactivating specific serving cell or serving cells of the SN. In some embodiments, the
25 DC may be LTE-DC, LET-NR DC (EN-DC), next generation core NR-LTE DC (NG
EN-DC), NR-LTE DC (NE-DC), or NR-DC.
[0055] In some embodiments in which the terminal device 120 is configured with carrier
aggregation and the terminal device 120 want to remain connected state in the first network,
the request may include a suggestion of the release or deactivation of at least part of serving
30 cells while remaining a connected state in the first communication network. For example,
the terminal device 120 may set the expected RRC state as a connected state, and indicate
releasing or deactivating all the serving cells configured. Alternatively, the terminal
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device 120 may set the expected RRC state as a connected state, and indicate releasing or
deactivating specific serving cell or serving cells.
[0056] According to embodiments of the present application, a timer for network switch is
defined. Now referring to FIG. 2, in some embodiments, upon transmitting 220 the
5 request, the terminal device 120 may start 230 the timer. In some embodiments, an upper
value of the timer may be broadcasted by system information from the first network device
110. Alternatively, an upper value of the timer may be configured by a RRC message
from the first network device 110. It should be noted that the upper value may also be
determined in any other suitable forms.
10 [0057] In some embodiments, if determining that the timer is not running, the terminal
device 120 may transmit the request for the switch. For example, in case that the switch
has not been performed and the timer is running, even if determining that next data is to be
performed between the terminal device 120 and the first network device 110, the terminal
device 120 shall not transmit another request for the switch. In this way, repeat
15 transmission of the request can be avoid, and transmission resource can be saved.
[0058] In some embodiments in which the first network device 110 ignores the request
and does not give a response to the request, the terminal device 120 may autonomously
perform 270 the switch to the second network device 111 at the expiration of the timer. In
some embodiments for performing the switch, the terminal device 120 may release the
20 connection with the first network device 110 so as to be in idle state in the first network,
and switch to the second network. In some alternative embodiments, the terminal device
120 may keep the connection with the first network device 110, and use a TDM pattern to
perform a switch between the first network device 110 and the second network device 111.
[0059] In some alternative embodiments, as shown in FIG. 2, upon receiving the request
25 for the switch, the first network device 110 may determine 240 a response to the request
and transmit 250 the response to the terminal device 120 within a time period
corresponding to the upper value of the timer. Upon receiving the response to the request,
the terminal device 120 may stop 260 the timer. In some embodiments, the response may
be transmitted in RRCRelease message. Alternatively, the response may be transmitted in
30 RRCReconfiguration message with switch gap configuration. It should be noted that the
above is merely an example, and the response may be transmitted in any other suitable
existing or future developed RRC message.
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[0060] In some embodiments, the first network device 110 may transmit a response (also
referred to as a first response below) indicating that the switch is rejected. In some
embodiments, the response may include a wait time for which a further request for the
switch is disabled to be transmitted by the terminal device 120. During the wait time, the
5 first network device 110 expects keeping connection with the terminal device 120 and the
terminal device 120 should not initiate another switch request within the wait time. In
some alternative or additional embodiments, the response may include a cause of the
rejection. For example, the cause may indicate that important service will be performed
between the terminal device 120 and the first network device 110. It should be noted that
10 the response may further include any other suitable contents. It should be also noted that
the cause may include any other suitable contents.
[0061] In some alternative embodiments, the first network device 110 may transmit a
response (also referred to as a second response below) indicating that the switch is allowed.
In some embodiments in which the first network device 110 supports a TDM pattern, the
15 response may include a TDM pattern to be used in a switch between the first and second
network devices 110 and 111.
[0062] In some embodiments in which a TDM pattern is decided by the first network
device 110, the first network device 110 may determine a TDM pattern based on service
information of the second network device 111 and a suggestion of the TDM pattern if any
20 received from the request, and incorporate the TDM pattern in the response to the request.
In some embodiments in which a TDM pattern is decided by the terminal device 120, the
first network device 110 may reject the suggestion of the TDM pattern by the terminal
device 120, and provide a suggested TDM pattern in the second response.
[0063] For example, the first network device 110 may transmit, to the terminal device 120,
25 a RRC message handling the request such as RRCRelease message and
RRCReconfiguration message with switch gap configuration. Upon receiving the RRC
message, the terminal device 120 may stop the timer. It should be noted that any other
existing or future developed RRC messages can also be used, and the present application
does not make limitation for this.
30 [0064] In some alternative embodiments, upon determining that a re-establishment of a
connection is initiated with the first network device 110, the terminal device 120 may stop
the timer. In some alternative embodiments, upon receiving a message of a handover from
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the first network device 110 to a third network device of the first communication network,
the terminal device 120 may stop the timer. For example, upon receiving
RRCReconfiguration message including reconfiguration WithSync, the terminal device 120
may stop the timer. In some embodiments in which the first network device 110 has
5 switch gap configuration for the terminal device 120, the switch gap configuration can be
passed from the first network device 110 as a source network device to the third network
device as a target network device during a handover. For example, the switch gap
configuration may be passed via HandoverPreparationlnformation message. It should be
noted that any other suitable messages are also feasible.
10 [0065] As stated above, upon receiving a response from the first network device 110
before an expiration of the timer, the terminal device 120 may stop 260 the timer. Then
the terminal device 120 may perform 270 the switch to the second network device 111
according to the response to the request. In some embodiments, the terminal device 120
may release the connection with the first network device 110 so as to be in idle or inactive
15 state in the first network, and switch to the second network. In some alternative
embodiments, the terminal device 120 may keep the connection with the first network
device 110, and use a TDM pattern to perform a switch between the first network device
110 and the second network device 111.
[0066] As shown in FIG. 2, in some embodiments in which the terminal device 120 want
20 to stop the TDM pattern, the terminal device 120 may transmit 280 or 280' an indication for
stopping the TDM pattern to the related network device. In some embodiments, if
determining that no data is to be transmitted between the terminal device 120 and the
second network device 111, the terminal device 120 may transmit 280 the indication to the
first network device 110. In some alternative embodiments, if determining that no data is
25 to be transmitted between the terminal device 120 and the first network device 110, the
terminal device 120 may transmit 280' the indication to the second network device 111.
[0067] In some embodiments, the terminal device 120 may transmit the indication via a
RRC message. In some embodiments, the terminal device 120 may transmit the
indication in an implicit way. For example, the terminal device 120 may send a RRC
30 message such as UEAssistanceinformation message with expected RRC state as connected
state and without TDM pattern information. Alternatively, the terminal device 120 may
transmit the indication in an explicit way. For example, the terminal device 120 may send
a RRC message such as UEAssistanceinformation message with explicit indication, such as
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a bit value.
[0068] In some alternative embodiments, the terminal device 120 may transmit the
indication via a media access control (MAC) control element (CE). In this way, the
terminal device 120 can use the MAC CE to activate or deactivate the TDM pattern.
5 [0069] In some embodiments in which the terminal device 120 is not able to return to the
first network by the end of the TDM pattern, the terminal device 120 may release the
connection with the first network device 110, and perform the procedure of going to idle
state. Alternatively, the terminal device 120 may take no action. That is, it is up to the
terminal device 120 whether to keep the connection with the first network device 110.
10 [0070] It should be note that actions shown in FIG. 2 are not always necessary for
implementing embodiments of the present disclosure, and more or less actions may be
adapted as needed. Corresponding to the processes described in FIG. 2, embodiments of
the present disclosure provide methods of communication implemented at a terminal device
and at a network device. These methods will be described below with reference to FIGs. 3
15 to 10.
[0071] FIG. 3 illustrates an example method 300 of communication implemented at a
terminal device in accordance with some embodiments of the present disclosure. For
example, the method 300 may be performed at the terminal device 120 as shown in FIG. 1.
For the purpose of discussion, in the following, the method 300 will be described with
20 reference to FIG. 1. It is to be understood that the method 300 may include additional
blocks not shown and/or may omit some blocks as shown, and the scope of the present
disclosure is not limited in this regard.
[0072] As shown in FIG. 3, at block 310, the terminal device 120 determines whether a
switch is to be performed from the first network device 110 to the second network device
25 111. In some embodiments, the first network of the first network device 110 may be
associated with a first identity (such as first USIM card 121) of the terminal device 120,
and the second network of the second network device 111 may be associated with a second
identity (such as second USIM card 122) of the terminal device 120. It should be noted
that the first network and the second network may be differentiated from each other in other
30 aspects of the terminal device 120 than in identities.
[0073] Upon determining that the switch is to be performed, at block 320, the terminal
device 120 transmits, to the first network device 110, a request for the switch from the first
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network device 110 to the second network device 111. In this way, the switch is notified
to the network side, and incorrect network performance recording can be avoided. Thus,
enhancement of performance during the network switch can be provided.
[0074] According to some embodiments of the present application, a timer is introduced
5 to regulate the terminal device 120's behavior for network switch. In some embodiments,
the terminal device 120 may start the timer upon transmitting the request. In some
embodiments in which data is determined to be transmitted to the second network device
111, the terminal device 120 may determine whether the timer is running, and transmit the
request for the switch in accordance with a determination that the timer is not running. In
10 this way, repeat transmission of a request for a switch can be effectively avoided.
[0075] In some embodiments, the terminal device 120 may perform the switch at
expiration of the timer. In some embodiments, the terminal device 120 may stop the timer
in response to at least one of the following: receiving a response to the request from the
first network device 110; determining that a re-establishment of a connection is initiated
15 with the first network device 110; or receiving a message of a handover from the first
network device 110 to a third network device of the first network. More details will be
described below with reference to FIGs. 4-7.
[0076] FIG. 4 illustrates another example method 400 of communication implemented at a
terminal device in accordance with some embodiments of the present disclosure. For
20 example, the method 400 may be performed at the terminal device 120 as shown in FIG. 1.
For the purpose of discussion, in the following, the method 400 will be described with
reference to FIG. 1. It is to be understood that the method 400 may include additional
blocks not shown and/or may omit some blocks as shown, and the scope of the present
disclosure is not limited in this regard.
25 [0077] As shown in FIG. 4, at block 410, the terminal device 120 may determine whether
data is to be transmitted between the terminal device 120 and the second network device
111. In some embodiments, if there is MO data to be transmitted to the second network
device 111, the terminal device 120 may determine that the data is to be transmitted. In
some alternative embodiments, if receiving a paging message from the second network
30 device 111, the terminal device 120 may determine that the data is to be transmitted.
[0078] Upon determining that the data is to be transmitted, at block 420, the terminal
device 120 may determine whether there is ongoing emergency service between the
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terminal device 120 and the first network device 110. If determining that there is no
ongoing emergency service between the terminal device 120 and the first network device
110, at block 403, the terminal device 120 may transmit, to the first network device 110, a
request for a switch from the first network device 110 to the second network device 111.
5 In this way, the quality of emergency service can be assured.
[0079] In some embodiments, the terminal device 120 may determine whether a timer for
network switch is running, and if determining that the timer is running, the terminal device
120 does not transmit the request to the first network device 110, and if determining that the
timer is not running, the terminal device 120 transmit the request to the first network device
10 110. In this way, unnecessary retransmission of the request can be avoided.
[0080] In some embodiments, the request may comprise at least one of the following: an
expected RRC state in the first network; a cause of the request; service information of the
second network; a suggestion of a TDM pattern; and a suggestion of the release or
deactivation of at least part of serving cells while remaining a connected state in the first
15 network. Other details of the request are similar with that described above in connection
with action 220 in FIG. 2, and are not repeated here.
[0081] Upon transmitting the request, at block 404, the terminal device 120 may start a
timer. In some embodiments, the terminal device 120 may receive an upper value of the
timer in system information from the first network device 110. Alternatively, the terminal
20 device 120 may receive the upper value of the timer in a dedicated RRC message from the
first network device 110. Based on the upper value, the terminal device 120 can manage
the timing of the timer.
[0082] At block 405, the terminal device 120 may determine whether the timer is expired.
If determining that the timer is not expired, at block 406, the terminal device 120 may
25 determine whether a response to the request is received from the first network device 110.
If determining at block 406 that the response is received, the terminal device 120 may stop
the timer at block 407.
[0083] At block 408, the terminal device 120 may determine whether the switch is
allowed or rejected based on the response. If the response indicates that the switch is
30 rejected (i.e., a first response), at block 409, the terminal device 120 may not enable to
transmit a further request for the switch for a wait time. In some embodiments in which
the wait time is configured by the first network device 110, the terminal device 120 may
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obtain the wait time from the response. It should be noted that the wait time may be
determined in any other suitable way.
[0084] If the response indicates that the switch is allowed (i.e., a second response), at
block 410, the terminal device 120 may perform the switch. If determining at block 406
5 that the response is not received, the terminal device 120 may return to block 405. If
determining at block 405 that the timer is expired, the terminal device 120 may enter block
410 to perform the switch.
[0085] In some embodiments for performing the switch, the terminal device 120 may
release a first connection with the first network device 110, and establish a second
10 connection with the second network device 111. In this way, the terminal device 120 may
be in an idle or inactive state in the first network, and in a connected state in the second
network.
[0086] In some alternative embodiments, the terminal device 120 may carry out a TDM
pattern between the first network and the second network. In this way, the terminal device
15 120 may perform expected data transmission in the second network while remaining a
connected state in the first network. This will be described in detail with reference to
FIGs. 5 and 6.
[0087] FIG. 5 illustrates another example method 500 of communication implemented at a
terminal device in accordance with some embodiments of the present disclosure. For
20 example, the method 500 may be performed at the terminal device 120 as shown in FIG. 1.
For the purpose of discussion, in the following, the method 500 will be described with
reference to FIG. 1. It is to be understood that the method 500 may include additional
blocks not shown and/or may omit some blocks as shown, and the scope of the present
disclosure is not limited in this regard. In this embodiment, the TDM pattern is decided
25 by the terminal device 120.
[0088] As shown in FIG. 5, at block 510, the terminal device 120 may determine a TDM
pattern associated with the switch. In some embodiments, the terminal device 120 may
decide to use a TDM pattern based on knowledge of the support of the TDM pattern by the
first network device 110. The knowledge may be obtained from system information
30 broadcasted by the first network device 110. In some embodiments, the terminal device
120 may determine the TDM pattern by determining at least one of the following: starting
information and duration of the switch (i.e. one shot switch gap); or a periodicity, a time
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domain offset and a length of absent time per cycle of the switch (i.e., periodical switch
gap).
[0089] At block 520, the terminal device 120 may perform the switch according to the
TDM pattern. In some embodiments, the terminal device 120 may perform data
5 transmission in the first and second networks according to the TDM pattern between the
first and second networks.
[0090] At block 530, the terminal device 120 may generate first information of the TDM
pattern for the first network device 110 and second information of the TDM pattern for the
second network device 111. In some embodiments, the first information and second
10 information may be adapted to meet respective time-domain requirements in the first and
second networks.
[0091] At block 540, the terminal device 120 may transmit the first information to the first
network device 110. For example, the terminal device 120 may transmit the first
information via UEAssistancelnformation message. It should be noted that any other
15 suitable messages are also feasible.
[0092] At block 550, the terminal device 120 may transmit the second information to the
second network device 111. For example, the terminal device 120 may transmit the
second information via RRCSetupComplete message. It should be noted that any other
suitable messages are also feasible.
20 [0093] In some alternative embodiments, the first network device 110 may re-negotiate
with the terminal device 120 for the TDM pattern. In some embodiments, the terminal
device 120 may provide a list of candidate TDM patterns for the first network device 110 to
select one of them. In some embodiments, in case that the terminal device 120 provides a
TDM pattern, the first network device 110 may reject it and provide a suggested TDM
25 pattern to the terminal device 120.
[0094] So far, embodiments about the case that the TDM pattern is decided by the
terminal device 120 is described with reference to FIG. 5. The following description will
be made in connection with FIG. 6 on the case that the TDM pattern is decided by the first
network device 110.
30 [0095] FIG. 6 illustrates another example method 600 of communication implemented at a
terminal device in accordance with some embodiments of the present disclosure. For
example, the method 600 may be performed at the terminal device 120 as shown in FIG. 1.
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For the purpose of discussion, in the following, the method 600 will be described with
reference to FIG. 1. It is to be understood that the method 600 may include additional
blocks not shown and/or may omit some blocks as shown, and the scope of the present
disclosure is not limited in this regard.
5 [0096] As shown in FIG. 6, at block 610, the terminal device 120 may receive, from the
first network device 110, a TDM pattern associated with the switch. In some embodiments,
the terminal device 120 may obtain the TDM pattern from a response to the request for the
switch received from the first network device 110. In some embodiments, the terminal
device 120 may obtain at least one of the following: starting information and duration of
10 the switch (i.e. one shot switch gap); or a periodicity, a time domain offset and a length of
absent time per cycle of the switch (i.e., periodical switch gap).
[0097] At block 620, the terminal device 120 may perform the switch according to the
TDM pattern. In some embodiments, the terminal device 120 may perform data
transmission in the first and second networks according to the TDM pattern between the
15 first and second networks.
[0098] At block 630, the terminal device 120 may generate second information of the
TDM pattern for the second network device 111 based on the received TDM pattern from
the network device 110. In some embodiments, the second information may be adapted to
meet time-domain requirements in the second network.
20 [0099] At block 640, the terminal device 120 may transmit the second information to the
second network device 111. For example, the terminal device 120 may transmit the
second information via RRCSetupComplete message. It should be noted that any other
suitable messages are also feasible.
[00100] So far, the activation of the TDM pattern is described. The following description
25 is made on the deactivation of the TDM pattern. FIG. 7 illustrates another example
method 700 of communication implemented at a terminal device in accordance with some
embodiments of the present disclosure. For example, the method 700 may be performed
at the terminal device 120 as shown in FIG. 1. For the purpose of discussion, in the
following, the method 700 will be described with reference to FIG. 1. It is to be
30 understood that the method 700 may include additional blocks not shown and/or may omit
some blocks as shown, and the scope of the present disclosure is not limited in this regard.

WHAT IS CLAIMED IS:
1. A method of communication, comprising:
determining, at a terminal device, whether a switch is to be performed from a first
network device of a first communication network to a second network device of a second
5 communication network, the first and second communication networks being associated
with first and second identities of the terminal device respectively; and
10
15
20
25
30
in response to determining that the switch is to be performed, transmitting, to the
first network device, a request for the switch from the first network device to the second
network device.
2. The method of claim 1, wherein the transmitting comprises:
determining whether a timer for network switch is running; and
in accordance with a determination that the timer is not running, transmitting the
request.
3. The method of claim 2, further comprising:
starting the timer upon transmitting the request.
4. The method of claim 3, further comprising:
performing the switch at expiration of the timer.
5. The method of claim 3, further comprising:
stopping the timer in response to at least one of the following:
receiving a response to the request from the first network device;
determining that a re-establishment of a connection is initiated with the first
network device; and
receiving a message of a handover from the first network device to a third
network device of the first communication network.
6. The method of claim 3, further comprising:
receiving, from the first network device, an upper value of the timer in at least one
of system information and a radio resource control (RRC) message.
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7. The method of claim 1, wherein determining whether the switch IS to be
performed comprises:
determining whether data is to be transmitted between the terminal device and the
second network device;
in accordance with a determination that the data is to be transmitted, determining
whether there is ongoing emergency service in the first communication network; and
in accordance with a determination that there is no ongoing emergency service in
the first communication network, determining that the switch is to be performed.
10 8. The method of claim 1, wherein the request compnses at least one of the
15
following:
an expected radio resource control (RRC) state in the first communication network;
a cause of the request;
service information of the second communication network;
a suggestion of a time-division multiplexing (TDM) pattern; and
a suggestion of the release or deactivation of at least part of serving cells while
remaining a connected state in the first communication network.
9. The method of claim 1, further comprising:
20 receiving, from the first network device, a first response to the request, the first
25
response indicating that the switch is rejected; and
in response to receiving the first response, disabling to transmit, to the first network
device, a further request for the switch for a wait time.
10. The method of claim 9, wherein the first response comprises at least one of the
wait time and a cause of the rejection.
11. The method of claim 1, further comprising:
receiving, from the first network device, a second response to the request, the
30 second response indicating that the switch is allowed; and
performing the switch in accordance with the response to the request.
12. The method of claim 4 or 11, wherein performing the switch comprises:
determining time-division multiplexing (TDM) pattern associated with the switch;
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and
performing, according to the TDM pattern, the switch while remaining a connection
with the first network device.
13. The method of claim 12, further comprising:
generating first information of the TDM pattern for the first network device and
second information of the TDM pattern for the second network device;
transmitting the first information to the first network device; and
transmitting the second information to the second network device.
14. The method of claim 12, wherein determining the TDM pattern compnses
determining at least one of the following:
starting information and duration of the switch; and
a periodicity, a time domain offset and a length of absent time per cycle of the
15 switch.
20
15. The method of claim 4 or 11, wherein performing the switch comprises:
receiving, from the first network device, time-division multiplexing (TDM) pattern
associated with the switch; and
performing, according to the TDM pattern, the switch while remaining a connection
with the first network device.
16. The method of claim 15, further comprising:
generating second information of the TDM pattern for the second network device;
25 and
30
transmitting the second information to the second network device.
17. The method of claim 15, wherein receiVmg the TDM pattern compnses
receiving at least one of the following:
starting information and duration of the switch; and
a periodicity, a time domain offset and a length of absent time per cycle of the
switch.
18. The method of claim 4 or 11, wherein performing the switch comprises:
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releasing a first connection with the first network device; and
establishing a second connection with the second network device.
19. The method of claim 1, further comprising:
5 in response to determining that no data is to be transmitted between the terminal
10
15
20
device and one of the first and second network devices, transmitting, to the other of the first
and second network devices, an indication for stopping time-division multiplexing (TDM)
pattern associated with the switch.
20. The method of claim 19, wherein transmitting the indication comprises:
transmitting the indication via a RRC message.
21. The method of claim 19, wherein transmitting the indication comprises:
transmitting the indication via a media access control (MAC) control element (CE).
22. The method of claim 1, further comprising:
in response to not enabling to return to the first communication network by the end
of time-division multiplexing (TDM) pattern, releasing a connection with the first network
device.
23. A method of communication, comprising:
receiving, at a first network device of a first communication network and from a
terminal device, a request for a switch from the first network device to a second network
device of a second communication network, the first and second communication networks
25 being associated with first and second identities of the terminal device respectively.
30
24. The method of claim 23, further comprising:
transmitting, to the terminal device, an upper value of a timer in at least one of
system information or a radio resource control (RRC) message.
25. The method of claim 24, further comprising:
transmitting a response to the request within a time period corresponding to the
upper value.
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26. The method of claim 25, wherein transmitting the response comprises:
transmitting, to the terminal device, a first response to the request, the first response
indicating that the switch is rejected.
5 27. The method of claim 26, wherein the first response comprises at least one of the
10
15
following:
a wait time for which a further request for the switch is disabled to be transmitted;
and
a cause of the rejection.
28. The method of claim 25, wherein transmitting the response comprises:
transmitting, to the terminal device, a second response to the request, the second
response indicating that the switch is allowed.
29. The method of claim 28, wherein transmitting the second response comprises:
determining a time-division multiplexing (TDM) pattern; and
transmitting the TDM pattern to the terminal device in the second response.
30. The method of claim 29, wherein determining the TDM pattern compnses
20 determining at least one of the following:
starting information and duration of the switch; and
a periodicity, a time domain offset and a length of absent time per cycle of the
switch.
25 31. The method of claim 23, wherein the request comprises at least one of the
30
following:
an expected radio resource control (RRC) state in the first communication network;
a cause of the request;
service information of the second communication network;
a suggestion of a time-division multiplexing (TDM) pattern; and
a suggestion of the release or deactivation of at least part of serving cells while
remaining a connected state in the first communication network.
32. The method of claim 23, further comprising:
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receiVmg, from the terminal device, time-division multiplexing (TDM) pattern
associated with the switch; and
performing data transmission with the terminal device according to the TDM
pattern.
33. The method of claim 23, further comprising:
receiving, from the terminal device, an indication for stopping time-division
multiplexing (TDM) pattern associated with the switch.
34. The method of claim 33, wherein receiving the indication comprises:
receiving the indication via a RRC message.
35. The method of claim 33, wherein receiving the indication comprises:
receiving the indication via a media access control (MAC) control element (CE).
36. A terminal device comprising:
a processor; and
a memory coupled to the processor and storing instructions thereon, the instructions,
when executed by the processor, causing the terminal device to perform the method
20 according to any of claims 1 to 22.
37. A network device comprising:
a processor; and
a memory coupled to the processor and storing instructions thereon, the instructions,
25 when executed by the processor, causing the network device to perform the method
according to any of claims 23 to 35.
38. A computer readable medium having instructions stored thereon, the
instructions, when executed on at least one processor, causing the at least one processor to
30 perform the method according to any of claims 1 to 22.
39. A computer readable medium having instructions stored thereon, the
instructions, when executed on at least one processor, causing the at least one processor to
perform the method according to any of claims 23 to 35.