Communication method and apparatus
A communication method includes receiving, by a terminal device, first information from a network device. The first information indicates a precoding matrix. The communication method also includes determining, by the terminal device, the precoding matrix based on the first information. The precoding matrix is for sending an uplink signal. The precoding matrix is determined based on a first matrix and a second matrix. At least one of the first matrix is determined from a first matrix set based on the first information, wherein the first matrix set is determined based on a horizontal-dimension parameter of an antenna of the terminal device; or the second matrix is determined from a second matrix set based on the first information, wherein the second matrix set is determined based on a vertical-dimension parameter of the antenna.
1. A communication method, comprising:
receiving, by a terminal device, first information from a network device, wherein the first information indicates a precoding matrix; and
determining, by the terminal device, the precoding matrix based on the first information, wherein the precoding matrix is for sending an uplink signal, wherein
the precoding matrix is further determined based on a first matrix and a second matrix; and
at least one of:
the first matrix is determined from a first matrix set based on the first information, wherein the first matrix set is determined based on a horizontal-dimension parameter of an antenna of the terminal device; or
the second matrix is determined from a second matrix set based on the first information, wherein the second matrix set is determined based on a vertical-dimension parameter of the antenna.
2. The communication method according to claim 1 , further comprising:
receiving, by the terminal device, second information from the network device, wherein the second information indicates a phase offset between antennas in different polarization directions of the terminal device; and
the determining, by the terminal device, the precoding matrix based on the first information comprises:
determining, by the terminal device, the precoding matrix based on the first information and the second information.
3. The communication method according to claim 2 , wherein the precoding matrix is a precoding matrix W that satisfies the following form:
w
=
[
v
t
,
m
v
t
,
m
·
e
j
θ
]
wherein v t,m is determined based on the first matrix and the second matrix, and θ is the phase offset.
4. The communication method according to claim 3 , wherein the second information indicates an index value of the phase offset θ in a set {0, 2π/M, . . . , 2π(M−1)/M}, wherein
a phase quantization factor M is configured by the network device or preset.
5. The communication method according to claim 1 , wherein the precoding matrix is a precoding matrix W that satisfies the following form:
W=v t,m
wherein v t,m is determined based on the first matrix and the second matrix.
6. The method according to claim 3 , wherein v t,m satisfies the following form:
v
t
,
m
[
u
m
e
j
2
π
t
O
1
N
1
…
u
m
e
j
2
π
t
(
N
1
-
1
)
O
1
N
1
]
wherein
u
m
=
[
1
e
j
·
2
π
m
N
2
·
O
2
…
e
j
·
2
π
m
(
N
2
-
1
)
N
2
·
O
2
]
,
N 1 is a quantity of horizontal-dimension antenna ports, O 1 is a horizontal-dimension oversampling factor, N 2 is a quantity of vertical-dimension antenna ports, j is an imaginary number, O 2 is a vertical-dimension oversampling factor, m=0, 1, 2, . . . N 2 O 2 −1, and t=0, 1, 2, . . . , N 2 O 2 −1.
7. The communication method according to claim 2 , wherein
the first information is transmitted via first signaling, and the second information is transmitted via second signaling; and
the first information is valid in a first time unit, and the second information is valid in a second time unit, wherein the first time unit is greater than or equal to the second time unit.
8. The communication method according to claim 1 , further comprising:
sending, by the terminal device, antenna configuration information to the network device, wherein the antenna configuration information comprises a polarization type of the antenna of the terminal device, the horizontal-dimension parameter of the antenna, and the vertical-dimension parameter of the antenna.
9. The communication method according to claim 1 , wherein the first information indicates an index value of the first matrix and an index value of the second matrix; or the first information indicates an index value of the precoding matrix.
10. A chip, comprising a processor, wherein the processor is coupled to a memory, and is configured to execute a computer program or instructions stored in the memory; and when the processor executes the computer program or the instructions, the method according to claim 1 is performed.
11. A communication method, comprising:
receiving, by a network device, antenna configuration information from a terminal device, wherein the antenna configuration information comprises an antenna parameter for determining a precoding matrix;
measuring, by the network device, a reference signal from the terminal device, to obtain a channel measurement result; and
determining, by the network device, the precoding matrix based on the channel measurement result and the antenna configuration information, and sending first information to the terminal device, wherein the first information indicates the precoding matrix, wherein
the precoding matrix is further determined based on a first matrix and a second matrix; and
at least one of:
the first matrix is determined from a first matrix set based on the channel measurement result, wherein the first matrix set is determined based on a horizontal-dimension parameter of an antenna of the terminal device; or
the second matrix is determined from a second matrix set based on the channel measurement result, wherein the second matrix set is determined based on a vertical-dimension parameter of the antenna.
12. The communication method according to claim 11 , further comprising:
sending, by the network device, second information to the terminal device, wherein the second information indicates a phase offset between antennas in different polarization directions of the terminal device.
13. The communication method according to claim 12 , wherein the precoding matrix is a precoding matrix W that satisfies the following form:
w
=
[
v
t
,
m
v
t
,
m
·
e
j
θ
]
wherein v t,m is determined based on the first matrix and the second matrix, and θ is the phase offset.
14. The communication method according to claim 12 , wherein the second information indicates an index value of the phase offset θ in a set {0, 2π/M, . . . , 2π(M−1)/M}, wherein
a phase quantization factor M is configured by the network device or preset.
15. The communication method according to claim 11 , wherein the precoding matrix is a precoding matrix W that satisfies the following form:
W=v t,m
wherein v t,m is determined based on the first matrix and the second matrix.
16. The method according to claim 13 , wherein v t,m satisfies the following form:
v
t
,
m
[
u
m
e
j
2
π
t
O
1
N
1
…
u
m
e
j
2
π
t
(
N
1
-
1
)
O
1
N
1
]
wherein
u
m
=
[
1
e
j
·
2
π
m
N
2
·
O
2
…
e
j
·
2
π
m
(
N
2
-
1
)
N
2
·
O
2
]
,
N 1 is a quantity of horizontal-dimension antenna ports, O 1 is a horizontal-dimension oversampling factor, N 2 is a quantity of vertical-dimension antenna ports, j is an imaginary number, O 2 is a vertical-dimension oversampling factor, m=0, 1, 2, . . . N 2 O 2 −1, and t=0, 1, 2, . . . , N 2 O 2 −1.
17. The communication method according to claim 11 , further comprising:
receiving, by the network device, antenna configuration information from the terminal device, wherein the antenna configuration information comprises a polarization type of the antenna of the terminal device, the horizontal-dimension parameter of the antenna, and the vertical-dimension parameter of the antenna.
18. The communication method according to claim 11 , wherein
the horizontal-dimension parameter of the antenna comprises a quantity of horizontal-dimension antenna ports; and
the vertical-dimension parameter of the antenna comprises a quantity of vertical-dimension antenna ports.
19. The communication method according to claim 11 , wherein the first information indicates an index value of the first matrix and an index value of the second matrix;
or the first information indicates an index value of the precoding matrix.
20. A chip, comprising a processor, wherein the processor is coupled to a memory, and is configured to execute a computer program or instructions stored in the memory; and when the processor executes the computer program or the instructions, the method according to claim 10 is performed.