Power control method and apparatus
The method includes: A first terminal device determines a transmit power of a data channel, wherein the transmit power of the data channel comprise a first data channel part and a transmit power of a second data channel part, where the first data channel part is a part of the data channel that has a same time domain resource with a control channel, and the second data channel part is another part of the data channel that has a different time domain resource with the control channel. The first terminal device sends data in the first data channel part at the transmit power of the first data channel part, and sends data in the second data channel part at the transmit power of the second data channel part. This application may be applied to internet of vehicles, for example, V2X, LTE-V, and V2V.
1. A method, comprising:
determining, by a first terminal device, a transmit power of a data channel, wherein the transmit power of the data channel comprises a transmit power of a first data channel part and a transmit power of a second data channel part, wherein the first data channel part is a part of the data channel and has a same time domain resource as a control channel, and the second data channel part is another part of the data channel and has a different time domain resource than the control channel, wherein the first data channel part does not overlap with the control channel in frequency domain, and wherein the transmit power of the first data channel part and the transmit power of the second data channel part satisfy:
P 2 =P 1 +10 log 10 (M/(M−N))[dBm], wherein P 2 is the transmit power of the second data channel part, P 1 is the transmit power of the first data channel part, a bandwidth of the control channel is N, and a bandwidth of the data channel is M, a bandwidth of the first data channel part is M−N, and a bandwidth of the second data channel part is M, and wherein M is greater than N; and
sending, by the first terminal device, data in the data channel at the transmit power of the data channel to a second terminal device, wherein data in the first data channel part is sent at the transmit power of the first data channel part, and data in the second data channel part is sent at the transmit power of the second data channel part.
2. The method according to claim 1 , wherein the transmit power of the first data channel part is determined based on a maximum transmit power, the bandwidth M−N of the first data channel part, and the bandwidth N of the control channel.
3. The method according to claim 1 , wherein the transmit power of the first data channel part satisfies:
P
1
=
min
{
P
CMAX
-
f
(
N
,
M
-
N
)
,
f
(
M
-
N
)
+
P
O
+
α
·
PL
,
P
MAX_CBR
-
f
(
N
,
M
-
N
)
}
,
wherein
P 1 is the transmit power of the first data channel part, P CMAX is a maximum transmit power, f(NM−N) is a function of the bandwidth M−N of the first data channel part and the bandwidth N of the control channel, f(M−N) is a function of the bandwidth M−N of the first data channel part, P o is a target received power of the second terminal device, PL is a reference link loss, α is a filtering parameter, and P MAX_CBR is a power determined based on a channel busy degree.
4. The method according to claim 3 , wherein:
the reference link loss PL is determined based on an uplink/downlink transmission loss in a serving cell or a sidelink transmission loss; and
the sidelink transmission loss is a link loss from the first terminal device to the second terminal device.
5. The method according to claim 4 , wherein the reference link loss satisfies:
PL=min{PL 1 , PL 2 }[dBm], wherein PL 1 indicates the sidelink transmission loss in sidelink communication, and PL 2 indicates the uplink/downlink transmission loss in the serving cell.
6. The method according to claim 1 , wherein the transmit power of the second data channel part is determined based on a maximum transmit power and a link budget of the second data channel part, and wherein the link budget of the second data channel part is determined based on the bandwidth M of the second data channel part.
7. The method according to claim 1 , wherein the transmit power of the second data channel part satisfies:
P 2 =min {P CMAX , f(M)+P O +α·PL,P MAX_CBR }, wherein P 2 is the transmit power of the second data channel part, P CMAX is a maximum transmit power, f(M) is a function of the bandwidth M of the second data channel part, P o is a target received power of the second terminal device, PL is a reference link loss, P MAX_CBR is a power determined based on a channel busy degree, and α is a filtering parameter; and
wherein the transmit power of the first data channel part is determined based on the maximum transmit power, the bandwidth M−N of the first data channel part, and the bandwidth N of the control channel, M is greater than N, and wherein the transmit power of the first data channel part satisfies:
P
1
=
min
{
P
CMAX
-
f
(
N
,
M
-
N
)
,
f
(
M
-
N
)
+
P
O
+
α
·
PL
,
P
MAX_CBR
-
f
(
N
,
M
-
N
)
}
,
wherein P 1 is the transmit power of the first data channel part, P CMAX is the maximum transmit power, f(N,M−N) is a function of the bandwidth M−N of the first data channel part and the bandwidth N of the control channel, f(M−N) is a function of the bandwidth M−N of the first data channel part, P o is the target received power of the second terminal device, PL is the reference link loss, α is the filtering parameter, and P MAX_CBR is the power determined based on the channel busy degree.
8. An apparatus, comprising:
one or more processors, wherein execution of instructions by the one or more processors causes the apparatus to:
determine a transmit power of a data channel, wherein the transmit power of the data channel comprises a transmit power of a first data channel part and a transmit power of a second data channel part, wherein the first data channel part is a part of the data channel and has a same time domain resource was a control channel, and the second data channel part is another part of the data channel and has a different time domain resource than the control channel, wherein the first data channel part does not overlap with the control channel in frequency domain, and wherein the transmit power of the first data channel part and the transmit power of the second data channel part satisfy:
P 2 =P 1 +10 log 10 (M/(M−N))[dBm], wherein P 2 is the transmit power of the second data channel part, P 1 is the transmit power of the first data channel part, a bandwidth of the control channel is N, a bandwidth of the data channel is M, a bandwidth of the first data channel part is M−N, and a bandwidth of the second data channel part is M, and wherein M is greater than N; and
send data in the data channel at the transmit power of the data channel to a second terminal device, wherein data in the first data channel part is sent at the transmit power of the first data channel part, and data in the second data channel part is sent at the transmit power of the second data channel part.
9. The apparatus according to claim 8 , wherein the transmit power of the first data channel part is determined based on a maximum transmit power, the bandwidth M−N of the first data channel part, and the bandwidth N of the control channel.
10. The apparatus according to claim 8 , wherein the transmit power of the first data channel part satisfies:
P
1
=
min
{
P
CMAX
-
f
(
N
,
M
-
N
)
,
f
(
M
-
N
)
+
P
O
+
α
·
PL
,
P
MAX_CBR
-
f
(
N
,
M
-
N
)
}
,
wherein
P 1 is the transmit power of the first data channel part, P CMAX is a maximum transmit power, f(N,M−N) is a function of the bandwidth M−N of the first data channel part and the bandwidth N of the control channel, f(M−N) is a function of the bandwidth M−N of the first data channel part, P o is a target received power of the second terminal device, PL is a reference link loss, α is a filtering parameter, and P MAX_CBR is a power determined based on a channel busy degree.
11. The apparatus according to claim 10 , wherein:
the reference link loss PL is determined based on an uplink/downlink transmission loss in a serving cell or a sidelink transmission loss; and
the sidelink transmission loss is a link loss from the apparatus to the second terminal device.
12. The apparatus according to claim 11 , wherein the reference link loss satisfies:
PL=min {PL 1 ,PL 2 }[dBm], wherein PL 1 indicates the sidelink transmission loss in sidelink communication, and PL 2 indicates the uplink/downlink transmission loss in the serving cell.
13. The apparatus according to claim 8 , wherein the transmit power of the second data channel part is determined based on a maximum transmit power and a link budget of the second data channel part, and the link budget of the second data channel part is determined based on the bandwidth M of the second data channel part.
14. The apparatus according to claim 8 , wherein the transmit power of the second data channel part satisfies:
P 2 =min{P CMAX ,f(M)+P O +α·PL,P MAX_CBR }, wherein P 2 is the transmit power of the second data channel part, P CMAX is a maximum transmit power, f(M) is a function of a bandwidth M of the second data channel part, P o is a target received power of the second terminal device, PL is a reference link loss, P MAX_CBR is a power determined based on a channel busy degree, and α is a filtering parameter; and
wherein the transmit power of the first data channel part is determined based on the maximum transmit power, the bandwidth M−N of the first data channel part, and the bandwidth N of the control channel, wherein M is greater than N, and wherein the transmit power of the first data channel part satisfies:
P
1
=
min
{
P
CMAX
-
f
(
N
,
M
-
N
)
,
f
(
M
-
N
)
+
P
O
+
α
·
PL
,
P
MAX_CBR
-
f
(
N
,
M
-
N
)
}
,
wherein P 1 is the transmit power of the first data channel part, P CMAX is the maximum transmit power, f(N,M−N) is a function of the bandwidth M−N of the first data channel part and the bandwidth N of the control channel, f(M−N) is a function of the bandwidth M−N of the first data channel part, P o is the target received power of the second terminal device, PL is the reference link loss, α is the filtering parameter, and P MAX_CBR is the power determined based on the channel busy degree.
15. A non-transitory computer-readable storage medium comprising instructions which, when executed by at least one processor of a computer, cause the computer to:
determine a transmit power of a data channel, wherein the transmit power of the data channel comprises a transmit power of a first data channel part and a transmit power of a second data channel part, wherein the first data channel part is a part of the data channel and has a same time domain resource as a control channel, and the second data channel part is another part of the data channel and has a different time domain resource than the control channel, wherein the first data channel part does not overlap with the control channel in frequency domain, and wherein the transmit power of the first data channel part and the transmit power of the second data channel part satisfy:
P 2 =P 1 +10 log 10 (M/(M−N))[dBm] wherein P 2 is the transmit power of the second data channel part, P 1 is the transmit power of the first data channel part, a bandwidth of the control channel is N, a bandwidth of the data channel is M, a bandwidth of the first data channel part is M−N, and a bandwidth of the second data channel part is M, and wherein M is greater than N; and
send data to a second terminal device at the transmit power of the data channel, wherein data in the first data channel part is sent at the transmit power of the first data channel part, and data in the second data channel part is sent at the transmit power of the second data channel part.
16. The non-transitory computer-readable storage medium according to claim 15 , wherein the transmit power of the first data channel part is determined based on a maximum transmit power, the bandwidth M−N of the first data channel part, and the bandwidth N of the control channel.
17. The non-transitory computer-readable storage medium according to claim 15 , wherein the transmit power of the first data channel part satisfies:
P
1
=
min
{
P
CMAX
-
f
(
N
,
M
-
N
)
,
f
(
M
-
N
)
+
P
O
+
α
·
PL
,
P
MAX_CBR
-
f
(
N
,
M
-
N
)
}
,
wherein P 1 is the transmit power of the first data channel part, P CMAX is a maximum transmit power, f(N,M−N) is a function of the bandwidth M−N of the first data channel part and the bandwidth N of the control channel, f(M−N) is a function of the bandwidth M−N of the first data channel part, P o is a target received power of the second terminal device, PL is a reference link loss, α is a filtering parameter, and P MAX_CBR is a power determined based on a channel busy degree.
18. The non-transitory computer-readable storage medium according to claim 17 , wherein:
the reference link loss PL is determined based on an uplink/downlink transmission loss in a serving cell or a sidelink transmission loss;
the sidelink transmission loss is a link loss from a first terminal device to the second terminal device; and
the reference link loss satisfies:
PL=min {PL 1 ,PL 2 }[dBm], wherein PL 1 indicates the sidelink transmission loss in sidelink communication, and PL 2 indicates the uplink/downlink transmission loss in the serving cell.
19. The non-transitory computer-readable storage medium according to claim 15 , wherein the transmit power of the second data channel part is determined based on a maximum transmit power and a link budget of the second data channel part, and wherein the link budget of the second data channel part is determined based on the bandwidth M of the second data channel part.
20. The non-transitory computer-readable storage medium according to claim 15 , wherein the transmit power of the second data channel part satisfies:
P 2 =min{P CMAX ,f(M)+P O +α·PL,P MAX_CBR }, wherein P 2 is the transmit power of the second data channel part, P CMAX is a maximum transmit power, f(M) is a function of a bandwidth M of the second data channel part, P o is a target received power of the second terminal device, PL is a reference link loss, P MAX_CBR is a power determined based on a channel busy degree, and α is a filtering parameter; and
wherein the transmit power of the first data channel part is determined based on the maximum transmit power, the bandwidth M−N of the first data channel part, and the bandwidth N of the control channel, M is greater than N, and wherein the transmit power of the first data channel part satisfies:
P
1
=
min
{
P
CMAX
-
f
(
N
,
M
-
N
)
,
f
(
M
-
N
)
+
P
O
+
α
·
PL
,
P
MAX_CBR
-
f
(
N
,
M
-
N
)
}
,
wherein P 1 is the transmit power of the first data channel part, P CMAX is the maximum transmit power, f(N,M−N) is a function of the bandwidth M−N of the first data channel part and the bandwidth N of the control channel, f(M−N) is a function of the bandwidth M−N of the first data channel part, P o is the target received power of the second terminal device, PL is the reference link loss, α is the filtering parameter, and P MAX_CBR is the power determined based on the channel busy degree.