Method and apparatus for configuring DMRS in wireless communication system
A communication method of a terminal with another terminal through a sidelink comprises: determining, by a first user device, one or more radio resource control (RRC) configurations comprising information of a demodulation reference signal (DMRS) for vehicle-to-everything (V2X) communication between user devices; determining, based on the one or more RRC configurations, a Physical Sidelink Control Channel (PSCCH) DMRS for a PSCCH; determining, based on a cyclic redundancy code of the PSCCH, an identifier; determining, based on the identifier, an initialization value associated with a Physical Sidelink Shared Channel (PSSCH) DMRS for a PSSCH; and via one or more orthogonal frequency division multiplexing (OFDM) symbols, transmitting, by the first user device to a second user device, the PSCCH DMRS and the PSSCH DMRS.
1 . A first user device comprising:
at least one antenna configured to receive at least one wireless signal from a base station, wherein the at least one wireless signal is received via a physical downlink channel;
at least one processor; and
at least one memory storing instructions that, when executed by the at least one processor, cause the first user device to:
determine at least one radio resource control (RRC) configuration comprising information of a demodulation reference signal (DMRS) for vehicle-to-everything (V2X) communication between user devices;
determine, based on the at least one RRC configuration, a Physical Sidelink Control Channel (PSCCH) DMRS for a PSCCH;
determine, based on a cyclic redundancy code of the PSCCH, an identifier, wherein the identifier corresponds to N ID n SCID , wherein N ID n SCID ∈{0, 1, 2, . . . , 65535}, and wherein N ID n SCID is determined based on the cyclic redundancy code of the PSCCH;
determine, based on the identifier, an initialization value of a DMRS sequence of a Physical Sidelink Shared Channel (PSSCH) DMRS for a PSSCH; and
via at least one orthogonal frequency division multiplexing (OFDM) symbol, transmit, to a second user device, the PSCCH DMRS and the PSSCH DMRS.
2 . The first user device of claim 1 , wherein the instructions, when executed by the at least one processor, cause the first user device to:
determine the PSCCH and the PSSCH; and
transmit, via the at least one OFDM symbol, the PSCCH and the PSSCH.
3 . The first user device of claim 1 , wherein the instructions, when executed by the at least one processor, cause the first user device to:
generate, based on the initialization value, the PSSCH DMRS.
4 . The first user device of claim 3 , wherein the initialization value is determined based on:
(
2
17
(
N
symb
slot
n
s
,
f
μ
+
l
+
1
)
(
2
N
ID
n
SCID
+
1
)
+
2
N
ID
n
SCID
+
n
SCID
)
mod
2
31
,
wherein N symb slot is a total number of symbols per slot, n s,f μ is a slot number within a frame, l is an OFDM symbol number, and n SCID is set to zero for the PSSCH DMRS.
5 . The first user device of claim 4 , wherein n SCID is not signaled to the first user device.
6 . The first user device of claim 4 , wherein N ID n SCID is determined based on a sidelink control information (SCI) identifier (ID), and
wherein the SCI ID is determined based on the cyclic redundancy code of the PSCCH.
7 . The first user device of claim 6 , wherein the SCI ID is a sidelink layer-1 ID.
8 . The first user device of claim 1 , wherein the instructions, when executed by the at least one processor, cause the first user device to determine the PSCCH DMRS by:
determining, based on the information of a DMRS for V2X communication between user devices, an initialization value, C init , associated with the PSCCH DMRS,
wherein the initialization value, C init , is determined based on:
(
2
17
(
14
n
s
,
f
μ
+
l
+
1
)
(
2
N
ID
0
+
1
)
+
2
N
ID
0
)
mod
2
31
,
wherein n s,f μ is a slot number within a frame, l is an OFDM symbol number, and N ID 0 ∈{0, 1, 2, . . . , 65535}, and
wherein N ID 0 is signaled by RRC signaling or a fixed value.
9 . The first user device of claim 1 , wherein the instructions, when executed by the at least one processor, cause the first user device to determine, based on sidelink control information (SCI) identifier (ID) information comprised in the PSCCH, the PSSCH DMRS.
10 . A first user device comprising:
at least one antenna configured to receive at least one wireless signal from a base station, wherein the at least one wireless signal is received via a physical downlink channel;
at least one processor; and
at least one memory storing instructions that, when executed by the at least one processor, cause the first user device to:
determine at least one radio resource control (RRC) configuration comprising information of a demodulation reference signal (DMRS) for vehicle-to-everything (V2X) communication between user devices;
receive, from a second user device, a Physical Sidelink Control Channel (PSCCH) DMRS for a PSCCH, wherein the PSCCH DMRS is based on the at least one RRC configuration;
demodulate, based on the PSCCH DMRS, the PSCCH;
determine, based on a cyclic redundancy code of the PSCCH, an identifier, wherein the identifier corresponds to N ID n SCID , wherein N ID n SCID ∈{0, 1, 2, . . . , 65535}, and wherein N ID n SCID is determined based on the cyclic redundancy code of the PSCCH;
determine, based on the identifier, an initialization value of a DMRS sequence of a Physical Sidelink Shared Channel (PSSCH) DMRS for a PSSCH;
receive, from the second user device, the PSSCH DMRS, wherein the PSSCH DMRS is associated with the initialization value; and
demodulate, based on the PSSCH DMRS, the PSSCH.
11 . The first user device of claim 10 , wherein the instructions, when executed by the at least one processor, cause the first user device to:
receive, via at least one orthogonal frequency division multiplexing (OFDM) symbol, the PSCCH and the PSSCH; and
determine, based on the PSCCH, the PSSCH DMRS.
12 . The first user device of claim 10 , wherein the instructions, when executed by the at least one processor, cause the first user device to:
determine, based on the initialization value, the PSSCH DMRS.
13 . The first user device of claim 12 , wherein the initialization value is determined based on:
(
2
17
(
N
symb
slot
n
s
,
f
μ
+
l
+
1
)
(
2
N
ID
n
SCID
+
1
)
+
2
N
ID
n
SCID
+
n
SCID
)
mod
2
31
,
wherein N symb slot is a total number of symbols per slot, n s,f μ is a slot number within a frame, l is an orthogonal frequency division multiplexing (OFDM) symbol number, and n SCID is set to zero for the PSSCH DMRS.
14 . The first user device of claim 13 , wherein n SCID is not signaled to the first user device.
15 . The first user device of claim 13 , wherein N ID n SCID is determined based on a sidelink control information (SCI) identifier (ID), and
wherein the SCI ID is determined based on the cyclic redundancy code of the PSCCH.
16 . The first user device of claim 15 , wherein the SCI ID is a sidelink layer-1 ID.
17 . The first user device of claim 10 , wherein the instructions, when executed by the at least one processor, cause the first user device to:
determine, based on the information of a DMRS for V2X communication between user devices, an initialization value, C init , associated with the PSCCH DMRS; and
determine the PSCCH DMRS,
wherein the initialization value, C init , is determined based on:
(
2
17
(
14
n
s
,
f
μ
+
l
+
1
)
(
2
N
ID
0
+
1
)
+
2
N
ID
0
)
mod
2
31
,
wherein n s,f μ is a slot number within a frame, l is an OFDM symbol number, and N ID 0 ∈{0, 1, 2, . . . , 65535}, and
wherein N ID 0 is signaled by RRC signaling or a fixed value.
18 . The first user device of claim 10 , wherein the instructions, when executed by the at least one processor, cause the first user device to determine, based on sidelink control information (SCI) identifier (ID) information comprised in the PSCCH, the PSSCH DMRS.