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 for
communication of a reference signal (RS).
BACKGROUND
10 [0002] In recent study on a new radio (NR) technology, it is agreed that enhancements on
aperiodic RS triggering are critical to facilitate more flexible triggering and downlink
control information (DCI) overhead or usage reduction. In this event, it has been
proposed to allow dynamic RS triggering slot offset indication. However, no detailed
solution on the dynamic indication is proposed, especially considering both triggering
15 flexibility and DCI overhead.
SUMMARY
[0003] In general, embodiments of the present disclosure provide methods, devices and
computer storage media for communication of a RS.
20 [0004] In a first aspect, there is provided a method of communication. The method
comprises: receiving, at a terminal device and from a network device, first information
about a first resource for communication of a reference signal and second information about
a modification of the first resource; determining a second resource based on the first and
second information; and performing the communication of the reference signal based on the
25 second resource.
[0005] In a second aspect, there is provided a method of communication. The method
comprises: determining, at a network device, first information about a first resource for
communication of a reference signal and second information about a modification of the
first resource; and transmitting the first and second information to a terminal device for
30 determination of a second resource for performance of the communication of the reference
signal.
[0006] In a third aspect, there IS provided a terminal device. The terminal device
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compnses 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.
[0007] In a fourth aspect, there is provided a network device. The network device
5 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.
[0008] 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
10 least one processor to perform the method according to the first aspect of the present
disclosure.
[0009] 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
15 present disclosure.
[0010] Other features of the present disclosure will become easily comprehensible
through the following description.
BRIEF DESCRIPTION OF THE DRAWINGS
20 [0011] 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:
[0012] FIG. 1 illustrates an example communication network in which some embodiments
of the present disclosure can be implemented;
25 [0013] FIG. 2 illustrates a schematic diagram illustrating a possible failure of
communication of a RS in a current RS triggering scheme;
[0014] FIG. 3 illustrates a schematic diagram illustrating a process for communication of
a RS according to embodiments of the present disclosure;
[0015] FIG. 4 illustrates an example method of communication implemented at a terminal
30 device in accordance with some embodiments of the present disclosure;
[0016] FIG. 5 illustrates a schematic time-frequency diagram illustrating an offset
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adjustment m a resource modification according to some embodiments of the present
disclosure;
[0017] FIG. 6 illustrates a schematic time-frequency diagram illustrating an effective time
of a resource modification according to some embodiments of the present disclosure;
5 [0018] FIG. 7 illustrates an example method of communication implemented at a network
device in accordance with some embodiments of the present disclosure; and
[0019] FIG. 8 is a simplified block diagram of a device that is suitable for implementing
embodiments of the present disclosure.
[0020] Throughout the drawings, the same or similar reference numerals represent the
10 same or similar element.
DETAILED DESCRIPTION
[0021] 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
15 purpose of illustration and help those skilled in the art to understand and implement the
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.
[0022] In the following description and claims, unless defined otherwise, all technical and
20 scientific terms used herein have the same meaning as commonly understood by one of
ordinary skills in the art to which this disclosure belongs.
[0023] 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
25 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
30 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
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"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
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
5 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.
[0024] In one embodiment, the terminal device may be connected with a first network
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
10 first network device and the second network device may use different radio access
technologies (RATs). In one embodiment, the first network device may be a first RAT
device and the second network device may be a second RAT device. In one embodiment,
the first RAT device is eNB and the second RAT device is gNB. Information related with
different RATs may be transmitted to the terminal device from at least one of the first
15 network device and the second network device. In one embodiment, a first information
may be transmitted to the terminal device from the first network device and a second
information may be transmitted to 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
20 transmitted from the second network device via the first network device. Information
related with reconfiguration for the 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.
[0025] As used herein, the singular forms 'a', 'an' and 'the' are intended to include the
25 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.'
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,'
30 and the like may refer to different or same objects. Other definitions, explicit and implicit,
may be included below.
[0026] 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
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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.
[0027] In current RS design in NR, a slot offset for aperiodic RS triggering IS
5 semi-statically configured by a higher layer parameter. For codebook, non-codebook or
antenna-switching based transmissions, only one aperiodic RS resource set for each of
these transmissions is supported, and thus only one slot offset is allowed for each of these
transmissions. However, due to variation of a slot format configuration, especially for
dynamic slot changing by DCI format 2_0, the slot offset configured for the aperiodic RS
10 resource may be unavailable in some cases.
[0028] In view of the above, embodiments of the present disclosure provide an improved
solution of dynamic configuring a RS resource. According to embodiments of the present
disclosure, information about a modification for a configured RS resource is transmitted
from a network device to a terminal device, so that the configured RS resource can be
15 updated or adjusted for ensuring a transmission of a RS. In this way, dynamic
configuration for a RS resource can be achieved, and flexibility of the RS resource
configuration can be enhanced. Principles and implementations of the present disclosure
will be described in detail below with reference to the figures.
[0029] According to embodiments of the present disclosure, a network device and a
20 terminal device may communicate with each other based on time slots (or slots for short) as
defined in the 3GPP specifications. For example, for subcarrier spacing configuration Jl,
slots are numbered n~ E { 01 ••• 1 N:1~~frame,J1 - 1 } in an increasing order within a subframe
an d nsJ1, f E {0I ••• I Nfsrlaomt e,Jl - 1 } m. an m. creasm. g ord e r wi. th "m a f rame. Nslot
There are symb
consecutive Orthogonal Frequency Division Multiplexing (OFDM) symbols in a slot where
25 N;}:~ depends on the cyclic prefix as given in related 3GPP specifications (TS 38.211), as
shown in Table 1 and Table 2 below. The start of slot n~ in a subframe is aligned in time
with the start of OFDM symbol n; N:}:~ in the same subframe. Other related definitions
and information of slots can be found in existing or future 3GPP specifications. More
generally, the term slot as used herein can refer to any existing defined unit of time or any
30 unit of time to be defined in the future.
5
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Table 1. Number of OFDM symbols per slot, slots per frame, and slots per
subframe for normal cyclic prefix.
11 Nslot
symb
Nframe,Jl
slot
Nsubframe,Jl
slot
0 14 10 1
1 14 20 2
2 14 40 4
3 14 80 8
4 14 160 16
Table 2. Number of OFDM symbols per slot, slots per frame, and slots per subframe
for extended cyclic prefix.
11 Nslot
symb
Nframe,Jl
slot
Nsubframe,Jl
slot
2 12 40 4
[0030] FIG. 1 illustrates a schematic diagram of an example communication network 100
in which embodiments of the present disclosure can be implemented. As shown in FIG. 1,
the communication network 100 may include a network device 110 and a terminal device
10 120 served by the network device 110. 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 communication network 100 may include any suitable number of
network devices and/or terminal devices adapted for implementing implementations of the
present disclosure.
15 [0031] As shown in FIG. 1, the network device 110 and the terminal device 120 may
communicate with each other via downlink and uplink channels such as wireless
communication downlink and uplink channels. For example, communication of a RS may
be performed between the network device 110 and the terminal device 120. In some
embodiments, the network device 110 may transmit a downlink RS to the terminal device
20 120 for at least one of channel evaluation/estimation, channel characteristic estimation and
compensation, phase noise estimation, time and/or frequency tracking and associated
demodulation of downlink transmission, and the terminal device 120 may correspondingly
receive the downlink RS. For example, the downlink RS may be any one or more of a
demodulation reference signal (DMRS), a cell reference signal (CRS), a multicast broadcast
25 single frequency network (MBSFN) reference signal, a positioning reference signal (PRS),
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a fine time/frequency tracking reference signal (TRS), a phase tracking reference signal
(PTRS) and a channel state information-reference signal (CSI-RS). It should be note that
the reference signal may be any downlink RS existing in the art or to be developed in the
future.
5 [0032] In some alternative embodiments, the terminal device 120 may transmit a RS (i.e.,
an uplink RS) to the network device 110 for at least one of channel evaluation/estimation,
channel characteristic estimation and compensation, phase noise estimation, time and/or
frequency tracking, channel estimation for downlink channel, and associated modulation of
uplink transmission, and the network device 110 may correspondingly receive the uplink
10 RS. For example, the RS may be any one or more of a sounding reference signal (SRS), a
demodulation reference signal (DMRS), a positioning reference signal (PRS), a fine
time/frequency tracking reference signal (TRS) and a phase tracking reference signal
(PTRS). It should be note that the reference signal may be any uplink RS existing in the
art or to be developed in the future.
15 [0033] The communications in the communication network 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
Code Division Multiple Access (WCDMA), Code Division Multiple Access (CDMA),
GSM EDGE Radio Access Network (GERAN), Machine Type Communication (MTC) and
20 the like. Furthermore, the communications may be performed according to any generation
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
(1G), the second generation (2G), 2.5G, 2.75G, the third generation (3G), the fourth
generation (4G), 4.5G, the fifth generation (5G) communication protocols.
25 [0034] As mentioned above, in current RS design in NR, for codebook, non-codebook or
antenna-switching based transmissions, only one aperiodic RS resource set for each of
these transmissions is supported, and thus only one slot offset is allowed for each of these
transmissions. However, due to variation of a slot format configuration, especially for
dynamic slot changing by DCI format 2_0, the slot offset configured for the aperiodic RS
30 resource may be unavailable in some cases. FIG. 2 illustrates a schematic diagram
illustrating a possible failure of communication of a RS in a current RS triggering scheme.
In this example, SRS is taken as an example of a RS for illustration.
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[0035] Reference sign 210 shows the case of suitable offset for the aperiodic SRS
resource, and reference sign 220 shows the case of unsuitable offset for the aperiodic SRS
resource. As shown by reference sign 210, slots m, m+ 1, m+2, m+4 and m+5 are
configured for downlink transmission (denoted as D in FIG.2) and slots m+3 is configured
5 for uplink transmission (denoted as U in FIG.2) according to current slot format
configuration. Assuming that an offset value of 3 is configured for SRS transmission.
When information triggering SRS transmission is received by the terminal device 120 in
slot m, a terminal device may transmit SRS in slot n+3 via an uplink transmission.
However, when the slot format configuration is varied, for example, as shown by reference
10 sign 220, slots m, m+ 1, m+3, m+4 and m+5 are configured for downlink transmission and
slots m+2 is configured for uplink transmission, there is no slot suitable for triggering SRS
transmission with slot offset 3. In addition, as shown in reference sign 210, only slot m is
suitable for aperiodic SRS triggering, as the configured slot offset is 3 in this example,
which may restrict the flexibility.
15 [0036] In addition, in current RS design in NR, the slot offset may be ranged from 0 to 32.
For the most flexible case, all available slot offset values are indicated by DCI. In this
case, 6 bits will be needed for transmission of the DCI, and thus a large DCI overhead will
be caused.
[0037] In view of the above, embodiments of the present disclosure provide an improved
20 solution of dynamic or flexible configuring a RS resource. According to embodiments of
the present disclosure, information about a modification for a configured RS resource is
transmitted from the network device 110 to the terminal device 120, so that the configured
RS resource can be updated or adjusted for a transmission of a RS. It will be described
with reference to FIG. 3.
25 [0038] FIG. 3 shows a schematic diagram illustrating a process 300 for communication of
a RS according to embodiments of the present disclosure. For the purpose of discussion,
the process 200 will be described with reference to FIG. 1. The process 300 may involve
the network device 110 and the terminal device 120 as illustrated in FIG. 1.
[0039] As shown in FIG. 3, the network device 110 may determine 310 first information
30 about a first resource configured for communication of a RS. As discussed above, the RS
may be any downlink or uplink reference signal existing in the art or to be developed in the
future. For the purpose of discussion, the following description will be made by taking a
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SRS as an example of the RS.
[0040] In some embodiments, the first information may comprise a first slot offset value
of the first resource. In some alternative embodiments, the first information may comprise
a set of slot offset values for the first resource. In some embodiments where multiple
5 resource sets are configured for the first resource, the first information may comprise a set
of slot offset values (also referred to as a first set of slot offset values below) for the
multiple resource sets. For example, the values of slot offset in the set are different to each
other. In some embodiments, the first set of slot offset values may comprise a slot offset
value for each of the multiple resource sets. In some embodiments, the number of slot
10 offset values in the first set of slot offset values may be smaller than the number of the
multiple resource sets.
[0041] The network device 110 transmits 320 the first information to the terminal device
120. In some embodiments, the network device 110 may configure the first information to
the terminal device 120 in a radio resource control (RRC) message. It should be note that
15 the first information may be transmitted in any other suitable ways, for example, in a media
access control (MAC) control element (CE) or a downlink control information (DCI), and
the present disclosure does not make limitation for this.
[0042] Depending on actual needs, such as a variation of a slot format configuration, the
network device 110 may determine 330 second information about a modification of the first
20 resource. In some embodiments, the second information may comprise a second slot
offset value for replacement of the first slot offset value. In some embodiments where
multiple resource sets are configured for the first resource and the first information
comprises a first set of slot offset values for the multiple resource sets, the second
information may comprise a second set of slot offset values in replacement of the first set of
25 slot offset values. In this way, the first resource can be updated, and flexibility of RS
resource configuration can be enhanced.
[0043] In some alternative embodiments, the second information may comprise an offset
value with respect to the first resource. In some embodiments where multiple resource
sets are configured for the first resource and the first information comprises a first set of
30 slot offset values for the multiple resource sets, the second information may comprise a set
of offset values with respect to the first set of slot offset values. In this way, the first
resource can be adjusted, and flexibility of RS resource configuration can be enhanced. In
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addition, the overhead for the adjustment can be reduced compared with that for the
replacement.
[0044] Upon determining the second information, the network device 110 may transmit
340 the second information to the terminal device 120. In some embodiments, the
5 network device 110 may transmit the second information in DCI. In some embodiments,
the network device 110 may transmit the second information in a media access control
(MAC) control element (CE). It should be note that the second information may be
transmitted in any other suitable ways, and the present disclosure does not make limitation
for this.

WHAT IS CLAIMED IS:
1. A method for communication, comprising:
receiving, at a terminal device and from a network device, first information about a
first resource for communication of a reference signal and second information about a
5 modification of the first resource;
10
and
determining a second resource based on the first and second information; and
performing the communication of the reference signal based on the second resource.
2. The method of claim 1, further comprising:
receiving third information triggering the communication of the reference signal,
wherein the determining comprises:
determining a slot of the reception of the third information; and
determining the second resource based on the first and second information and
15 the slot.
3. The method of claim 1, wherein the receiving comprises:
receiving the first information in a radio resource control (RRC) message from the
network device; and
20 receiving the second information in at least one of a media access control (MAC)
25
30
control element (CE) and downlink control information (DCI) from the network device.
4. The method of claim 1, wherein the first information comprises a first slot
offset value, and the second information comprises a second slot offset value, and
wherein the determining comprises:
determining the second resource based on the second slot offset value.
5. The method of claim 4, wherein the second slot offset value is above the first
slot offset value.
6. The method of claim 4, wherein the determining comprises:
determining whether a resource determined based on the second slot offset
value is available; and
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in accordance with a determination that the resource is available, determining
the second resource based on the second slot offset value.
7. The method of claim 1, wherein the first information comprises a set of first slot
5 offset values, and the second information comprises at least one of the following:
a subset in the set; and
a slot offset value from the set.
8. The method of claim 1, wherein the first information comprises a first set of slot
10 offset values for multiple resource sets of the first resource, and the second information
comprises a second set of slot offset values, and
15
20
wherein the determining comprises:
determining multiple resource sets of the second resource based on the second
set of slot offset values.
9. The method of claim 1, wherein the first information comprises a first slot
offset value, and the second information comprises an offset value with respect to the first
slot offset value, and
wherein the determining comprises:
determining the second resource based on the first slot offset value and the
offset value.
10. The method of claim 9, wherein determining the second resource comprises:
in accordance with a determination that a sum of the first slot offset value and the
25 offset value is above a first value and below a second value larger than the first value,
determining the second resource based on the sum.
11. The method of claim 9, wherein the offset value is selected from a set of offset
values, an offset value in the set being associated with at least one of the first slot offset
30 value and a slot format configuration.
12. The method of claim 9, further comprising:
receiving, within a predetermined time duration from the reception of the second
information, fourth information comprising a further offset value with respect to a sum of
5
10
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the first slot offset value and the offset value; and
wherein determining the second resource comprises:
PCT/CN2020/089273
determining the second resource based on the sum and the further offset value.
13. The method of claim 9, wherein the performing comprises:
determining whether a first slot is later than a second slot, the first slot being a slot
later than a slot of a downlink control channel triggering the communication of the
reference signal by a sum of the first slot offset value and the offset value, the second slot
being a slot later than a slot of the second resource by a third value; and
in accordance with a determination that the first slot is later than the second slot,
performing the communication of the reference signal based on the second resource.
14. The method of claim 1, wherein the first information comprises a first set of
slot offset values for multiple resource sets of the first resource, and the second information
15 comprises a set of offset values with respect to the first set of slot offset values, and
20
wherein the determining comprises:
determining multiple resource sets of the second resource based on the first set
of slot offset values and the set of offset values.
15. The method of claim 1, wherein the performing comprises:
determining a time interval between the last symbol of a downlink control channel
and the first symbol of the second resource, the downlink control channel triggering the
communication of the reference signal; and
in accordance with a determination that the time interval is above a fourth value,
25 performing the communication of the reference signal.
16. A method for communication, comprising:
determining, at a network device, first information about a first resource for
communication of a reference signal and second information about a modification of the
30 first resource; and
transmitting the first and second information to a terminal device for determination
of a second resource for performance of the communication of the reference signal.
17. The method of claim 16, further comprising:
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transmitting third information triggering the communication of the reference signal.
18. The method of claim 16, wherein the transmitting comprises:
transmitting the first information in a radio resource control (RRC) message; and
5 transmitting the second information in at least one of a media access control (MAC)
control element (CE) and downlink control information (DCI).
19. The method of claim 16, wherein the determining comprises:
causing a first slot offset value of the first resource to be included in the first
10 information; and
causmg a second slot offset value of the second resource to be included in the
second information.
20. The method of claim 19, wherein the second slot offset value is above the first
15 slot offset value.
21. The method of claim 16, wherein the determining comprises:
causing a set of first slot offset values to be included in the first information; and
causing at least one of the following to be included in the second information:
20 a subset in the set; and
a slot offset value from the set.
22. The method of claim 16, wherein the determining comprises:
causing a first set of slot offset values for multiple resource sets of the first resource
25 to be included in the first information; and
30
causing a second set of slot offset values to be included in the second information.
23. The method of claim 16, wherein the determining comprises:
causing a first slot offset value to be included in the first information; and
causing an offset value with respect to the first slot offset value to be included in the
second information.
24. The method of claim 23, wherein the offset value is selected from a set of
offset values, an offset value in the set being associated with at least one of the first slot
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offset value and a slot format configuration.
25. The method of claim 23, further comprising:
transmitting, within a time duration from the transmission of the second information,
5 fourth information comprising a further offset value with respect to a sum of the first slot
offset value and the offset value.
26. The method of claim 16, wherein the determining comprises:
causing a first set of slot offset values for multiple resource sets of the first resource
10 to be included in the first information; and
causing a set of offset values with respect to the first set of slot offset values to be
included in the second information.
27. A terminal device comprising:
15 a processor; and
20
25
30
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
according to any of claims 1 to 15.
28. A network device comprising:
a processor; and
a memory coupled to the processor and storing instructions thereon, the instructions,
when executed by the processor, causing the network device to perform the method
according to any of claims 16 to 26.
29. 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 1 to 15.
30. 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 16 to 26.