Terminal apparatus for controlling uplink signal transmission power and method for same
A terminal apparatus for controlling uplink signal transmission power and a method for same are disclosed. A method for the terminal, which communicates with a plurality of cooperation nodes that are controlled by one base station in one cell, controlling the uplink signal transmission power in a wireless communication system comprises the steps of: receiving diversity gain information of the plurality of cooperation nodes; determining the uplink transmission power of the uplink signal by considering the diversity gain information; and transmitting the uplink signal at the uplink transmission power that is decided, wherein the diversity gain information is an offset value which considers a diversity margin of the plurality of cooperation nodes.
1. A method for controlling uplink transmit (Tx) power of a terminal communicating with a plurality of cooperation nodes controlled by one base station in one cell in a wireless communication system, the method comprising:
receiving diversity gain information of the plurality of cooperation nodes;
determining uplink Tx power of an uplink signal in consideration of the diversity gain information; and
transmitting the uplink signal with the determined uplink Tx power,
wherein the diversity gain information is an offset value,
wherein the offset value is set considering a diversity margin of the plurality of cooperation nodes when the plurality of cooperation nodes and the terminal have identical link characteristics, and
wherein the offset value is set considering a diversity margin of a node having a comparatively poor link among the plurality of cooperation nodes when the plurality of cooperation nodes and the terminal have different link characteristics.
2. The method according to claim 1 , wherein the diversity gain information of the plurality of cooperation nodes is signaled from the plurality of cooperation nodes.
3. The method according to claim 1 , wherein the plurality of cooperation nodes are remote radio heads (RRHs) or wired antennas of a distributed antenna system (DAS).
4. The method according to claim 1 , wherein, when the uplink signal is a physical uplink shared channel (PUSCH), the determined uplink Tx power corresponds to the following equation A
P
PUSCH
,
c
(
i
)
=
min
{
P
CMAX
,
c
(
i
)
,
10
log
10
(
M
PUSCH
,
c
(
i
)
)
+
P
O_PUSCH
,
c
(
j
)
+
α
c
(
j
)
·
PL
c
+
Δ
TF
,
c
(
i
)
+
f
c
(
i
)
-
offset
BS_Diversity
_margin
}
[
Equation
A
]
wherein c indicates the index of the specific cell, i represents a subframe index, P PUSCH,c (i) is PUSCH Tx power in the subframe i of the specific cell c, P CMAX,c (i) is maximum Tx power of the terminal, P O — PUSCH,c (j) is a parameter corresponding to the sum of a cell-specific nominal component P O — NOMINAL — PUSCH,c (j) provided by a higher layer of the specific cell c and a UE-specific component P O — UE — PUSCH,c (j) provided by the higher layer, α c (j) is a cell-specific parameter, PL c is a downlink pathloss estimate calculated in dB by the terminal of the specific cell c, f c (i) is a value indicating a current PUSCH power control adjustment state for the subframe i of the specific cell c, Δ TF, c (i) is a value for one codeword of the specific cell c, and offset BS — Diversity — margin is the offset value.
5. The method according to claim 1 , wherein, when the uplink signal is a PUSCH and the PUSCH and a PUCCH are simultaneously transmitted, the determined uplink Tx power corresponds to the following equation B
P
PUSCH
,
c
(
i
)
=
min
{
10
log
10
(
P
^
CMAX
,
c
(
i
)
-
P
^
PUCCH
(
i
)
)
,
10
log
10
(
M
PUSCH
,
c
(
i
)
)
+
P
O_PUSCH
,
c
(
j
)
+
α
c
(
j
)
·
PL
c
+
Δ
TF
,
c
(
i
)
+
f
c
(
i
)
-
offset
BS_Diversity
_margin
}
[
Equation
B
]
wherein c indicates the index of the specific cell, i represents a subframe index, P PUSCH,c (i) is PUSCH Tx power in the subframe i of the specific cell c, {circumflex over (P)} PUCCH,c (i) is the linear value of PUCCH Tx power, {circumflex over (P)} CMAX,c (i) is the linear value of maximum Tx power P CMAX,c (i) of the terminal, P O — PUSCH,c (j) is a parameter corresponding to the sum of a cell-specific nominal component P O — NOMINAL — PUSCH,c (j) provided by a higher layer of the specific cell c and a UE-specific component P O — UE — PUSCH,c (j) provided by the higher layer, α c (j) is a cell-specific parameter, PL c is a downlink pathloss estimate calculated in dB by the terminal of the specific cell c, f c (i) is a value indicating a current PUSCH power control adjustment state for the subframe i of the specific cell c, Δ TF, c (i) is a value for one codeword of the specific cell c, and offset BS — Diversity — margin is the offset value.
6. The method according to claim 1 , wherein a power headroom corresponding to Tx power usable as the uplink signal conforms to the following equation C
PH type1,c ( i )= P CMAX,c ( i )−{10 log 10 ( M PUSCH,c ( i ))+ P O — PUSCH,c ( j )+α c ( j )· PL c +Δ TF,c ( i )+ f c ( i )−offset BS — Diversity — margin } [Equation C]
wherein c indicates the index of the specific cell, i represents a subframe index, PH Type1,c (i) is power headroom power in the subframe i of the specific cell c, P CMAX,c (i) is maximum Tx power of the terminal, M PUSCH,c (i) is a parameter indicating a PUSCH resource allocation bandwidth represented by the number of effective resource blocks for the subframe i of the specific cell c, P O — PUSCH,c (j) is a parameter corresponding to the sum of a cell-specific nominal component P O — NOMINAL — PUSCH,c (j) provided by a higher layer of the specific cell c and a UE-specific component P O — UE — PUSCH,c (j) provided by the higher layer, α c (j) is a cell-specific parameter, PL c is a downlink pathloss estimate calculated in dB by the terminal of the specific cell c, f c (i) is a value indicating a current PUSCH power control adjustment state for the subframe i of the specific cell c, Δ TF, c (i) is a value for one codeword of the specific cell c, and offset BS — Diversity — margin is the offset value.
7. The method according to claim 1 , wherein, when the uplink signal is a physical uplink control channel (PUCCH), the determined uplink Tx power corresponds to the following equation D
P
PUCCH
(
i
)
=
min
{
P
CMAX
,
c
(
i
)
,
P
0
_PUCCH
+
PL
c
+
h
(
n
CQI
,
n
HARQ
,
n
SR
)
+
Δ
F_PUCCH
(
F
)
+
Δ
TxD
(
F
′
)
+
g
(
i
)
-
offset
BS_Diversity
_margin
}
[
Equation
D
]
wherein c indicates the index of the specific cell, i represents a subframe index, P PUCCH (i) is PUCCH Tx power in the subframe i of the specific cell c, P CMAX,c (i) is maximum Tx power of the terminal, P O — PUSCH,c (j) is a parameter corresponding to the sum of a cell-specific nominal component P O — NOMINAL — PUSCH,c (j) provided by a higher layer of the specific cell c and a UE-specific component P O — UE — PUSCH,c (j) provided by the higher layer, α c (j) is a cell-specific parameter, PL c is a downlink pathloss estimate calculated in dB by the terminal of the specific cell c, h(n CQI ,n HARQ ,n SR ) is a value varied according to PUCCH format, n CQI represents the number of information bits of channel quality information (CQI), n HARQ represents the number of HARQ bits, n SR is a value indicating whether a specific subframe has a PUSCH transport block, Δ F — PUCCH (F) is a relative value for PUCCH format 1 a , g(i) is a value indicating a current PUCCH power control adjustment state of the subframe i, Δ TxD (F′) is a value determined by a higher layer in which PUCCH format F′ is defined when the PUCCH is configured by the terminal such that the PUCCH is transmitted through two antenna ports, and offset BS — Diversity — margin is the offset value.
8. The method according to claim 1 , wherein, when the uplink signal is a sounding reference symbol (SRS), the determined uplink Tx power corresponds to the following equation E
P SRS,c ( i )=min{ P CMAX,c ( i ), P SRS — OFFSET,c ( m )+10 log 10 ( M SRS,c )+ P O — PUSCH,c ( j )+α c ( j )· PL c +f c ( i )−offset BS — Diversity — margin } [Equation E]
wherein c indicates the index of the specific cell, i represents a subframe index, P SRS,c (i) is SRS Tx power in the subframe i of the specific cell c, P CMAX,c (i) is maximum Tx power of the terminal, P SRS — OFFSET,c (m) is a UE-specific parameter corresponding to a power offset value for SRS transmission of the specific cell c, M SRS,c is SRS transmission bandwidth represented by the number of resource blocks, P O — PUSCH,c (j) is a parameter corresponding to the sum of a cell-specific nominal component P O — NOMINAL — PUSCH,c (j) provided by a higher layer of the specific cell c and a UE-specific component P O — UE — PUSCH,c (j) provided by the higher layer, α c (j) is a cell-specific parameter, PL c is a downlink pathloss estimate calculated in dB by the terminal of the specific cell c, f c (i) is a value indicating a current PUSCH power control adjustment state for the subframe i of the specific cell c, and offset BS — Diversity — margin is the offset value.
9. The method according to claim 1 , wherein, when the uplink signal is a random access channel (RACH), the determined uplink Tx power corresponds to the following equation F
P PRACH =min{ P CMAX,c ( i ), PREAMBLE_RECEIVED_TARGET_POWER+ PL c −offset BS — Diversity — margin } [Equation F]
wherein c indicates the index of the specific cell, i represents a subframe index, P PRACH is RACH Tx power in the subframe i of the specific cell c, PREAMBLE_RECEIVED_TARGET_POWER represents receive (Rx) power of a RACH preamble targeted by a BS, PL c is a downlink pathloss estimate calculated in dB by the terminal of the specific cell c, and offset BS — Diversity — margin is the offset value.
10. A terminal communicating with a plurality of cooperation nodes controlled by one base station in one cell, for controlling uplink Transmit (Tx) power in a wireless communication system, the terminal comprising:
a transceiver configured to transmit and receive a signal; and
a processor configured to control the transceiver,
wherein the processor is further configured to:
control the transceiver to receive diversity gain information of the plurality of cooperation nodes,
determine uplink Tx power of an uplink signal in consideration of the diversity gain information, and
control the transceiver to transmit the uplink signal with the determined uplink Tx power,
wherein the diversity gain information is an offset value,
wherein the offset value is set considering a diversity margin of the plurality of cooperation nodes when the plurality of cooperation nodes and the terminal have identical link characteristics, and
wherein the offset value is set considering a diversity margin of a node having a comparatively poor link among the plurality of cooperation nodes when the plurality of cooperation nodes and the terminal have different link characteristics.
11. The terminal according to claim 10 , wherein the diversity gain information of the plurality of cooperation nodes is signaled from the plurality of cooperation nodes.
12. The terminal according to claim 10 , wherein the plurality of cooperation nodes are RRHs or wired antennas of a DAS.
13. The terminal according to claim 10 , wherein, when the uplink signal is a PUSCH, the determined uplink Tx power corresponds to the following equation A
P
PUSCH
,
c
(
i
)
=
min
{
P
CMAX
,
c
(
i
)
,
10
log
10
(
M
PUSCH
,
c
(
i
)
)
+
P
O_PUSCH
,
c
(
j
)
+
α
c
(
j
)
·
PL
c
+
Δ
TF
,
c
(
i
)
+
f
c
(
i
)
-
offset
BS_Diversity
_margin
}
[
Equation
A
]
wherein c indicates the index of the specific cell, i represents a subframe index, P PUSCH,c (i) is PUSCH Tx power in the subframe i of the specific cell c, P CMAX,c (i) is maximum Tx power of the terminal, P O — PUSCH,c (j) is a parameter corresponding to the sum of a cell-specific nominal component P O — NOMINAL — PUSCH,c (j) provided by a higher layer of the specific cell c and a UE-specific component P O — UE — PUSCH,c (j) provided by the higher layer, α c (j) is a cell-specific parameter, PL c is a downlink pathloss estimate calculated in dB by the terminal of the specific cell c, f c (i) is a value indicating a current PUSCH power control adjustment state for the subframe i of the specific cell c, Δ TF, c (i) is a value for one codeword of the specific cell c, and offset BS — Diversity — margin is the offset value.
14. The terminal according to claim 10 , wherein, when the uplink signal is a PUSCH and the PUSCH and a PUCCH are simultaneously transmitted, the determined uplink Tx power corresponds to the following equation B
P
PUSCH
,
c
(
i
)
=
min
{
10
log
10
(
P
^
CMAX
,
c
(
i
)
-
P
^
PUCCH
(
i
)
)
,
10
log
10
(
M
PUSCH
,
c
(
i
)
)
+
P
O_PUSCH
,
c
(
j
)
+
α
c
(
j
)
·
PL
c
+
Δ
TF
,
c
(
i
)
+
f
c
(
i
)
-
offset
BS_Diversity
_margin
}
[
Equation
B
]
wherein c indicates the index of the specific cell, i represents a subframe index, P PUSCH,c (i) is PUSCH Tx power in the subframe i of the specific cell c, {circumflex over (P)} PUCCH,c (i) is the linear value of PUCCH Tx power, {circumflex over (P)} CMAX,c (i) is the linear value of maximum Tx power P CMAX,c (i) of the terminal, P O — PUSCH,c (j) is a parameter corresponding to the sum of a cell-specific nominal component P O — NOMINAL — PUSCH,c (j) provided by a higher layer of the specific cell c and a UE-specific component P O — UE — PUSCH,c (j) provided by the higher layer, α c (j) is a cell-specific parameter, PL c is a downlink pathloss estimate calculated in dB by the terminal of the specific cell c, f c (i) is a value indicating a current PUSCH power control adjustment state for the subframe i of the specific cell c, Δ TF, c (i) is a value for one codeword of the specific cell c, and offset BS — Diversity — margin is the offset value.
15. The terminal according to claim 10 , wherein a power headroom corresponding to Tx power usable as the uplink signal conforms to the following equation C
PH type1,c ( i )= P CMAX,c ( i )−{10 log 10 ( M PUSCH,c ( i ))+ P O — PUSCH,c ( j )+α c ( j )· PL c +Δ TF,c ( i )+ f c ( i )−offset BS — Diversity — margin } [Equation C]
wherein c indicates the index of the specific cell, i represents a subframe index, PH Type1,c (i) is power headroom power in the subframe i of the specific cell c, P CMAX,c (i) is maximum Tx power of the terminal, M PUSCH,c (i) is a parameter indicating a PUSCH resource allocation bandwidth represented by the number of effective resource blocks for the subframe i of the specific cell c, P O — PUSCH,c (j) is a parameter corresponding to the sum of a cell-specific nominal component P O — NOMINAL — PUSCH,c (j) provided by a higher layer of the specific cell c and a UE-specific component P O — UE — PUSCH,c (j) provided by the higher layer, α c (j) is a cell-specific parameter, PL c is a downlink pathloss estimate calculated in dB by the terminal of the specific cell c, f c (i) is a value indicating a current PUSCH power control adjustment state for the subframe i of the specific cell c, Δ TF, c (i) is a value for one codeword of the specific cell c, and offset BS — Diversity — margin is the offset value.
16. The terminal according to claim 10 , wherein, when the uplink signal is a PUCCH, the determined uplink Tx power corresponds to the following equation D
P
PUCCH
(
i
)
=
min
{
P
CMAX
,
c
(
i
)
,
P
0
_PUCCH
+
PL
c
+
h
(
n
CQI
,
n
HARQ
,
n
SR
)
+
Δ
F_PUCCH
(
F
)
+
Δ
TxD
(
F
′
)
+
g
(
i
)
-
offset
BS_Diversity
_margin
}
[
Equation
D
]
wherein c indicates the index of the specific cell, i represents a subframe index, P PUCCH (i) is PUCCH Tx power in the subframe i of the specific cell c, P CMAX,c (i) is maximum Tx power of the terminal, P O — PUSCH,c (j) is a parameter corresponding to the sum of a cell-specific nominal component P O — NOMINAL — PUSCH,c (j) provided by a higher layer of the specific cell c and a UE-specific component P O — UE — PUSCH,c (j) provided by the higher layer, α c (j) is a cell-specific parameter, PL c is a downlink pathloss estimate calculated in dB by the terminal of the specific cell c, h(n CQI , n HARQ ,n SR ) is a value varied according to PUCCH format, n CQI represents the number of information bits of channel quality information (CQI), n HARQ represents the number of HARQ bits, n SR is a value indicating whether a specific subframe has a PUSCH transport block, Δ F — PUCCH (F) is a relative value for PUCCH format 1 a , g(i) is a value indicating a current PUCCH power control adjustment state of the subframe i, Δ TxD (F′) is a value determined by a higher layer in which PUCCH format F′ is defined when the PUCCH is configured by the terminal such that the PUCCH is transmitted through two antenna ports, and offset BS — Diversity — margin is the offset value.
17. The terminal according to claim 10 , wherein, when the uplink signal is a SRS, the determined uplink Tx power corresponds to the following equation E
P SRS,c ( i )=min{ P CMAX,c ( i ), P SRS — OFFSET,c ( m )+10 log 10 ( M SRS,c )+ P O — PUSCH,c ( j )α c ( j )· PL c +f c ( i )−offset BS — Diversity — margin } [Equation E]
wherein c indicates the index of the specific cell, i represents a subframe index, P SRS,c (i) is SRS Tx power in the subframe i of the specific cell c, P CMAX,c (i) is maximum Tx power of the terminal, P SRS — OFFSET,c (m) is a UE-specific parameter corresponding to a power offset value for SRS transmission of the specific cell c, M SRS,c is SRS transmission bandwidth represented by the number of resource blocks, P O — PUSCH,c (j) is a parameter corresponding to the sum of a cell-specific nominal component P O — NOMINAL — PUSCH,c (j) provided by a higher layer of the specific cell c and a UE-specific component P O — UE — PUSCH,c (j) provided by the higher layer, α c (j) is a cell-specific parameter, PL c is a downlink pathloss estimate calculated in dB by the terminal of the specific cell c, f c (i) is a value indicating a current PUSCH power control adjustment state for the subframe i of the specific cell c, and offset BS — Diversity — margin is the offset value.
18. The terminal according to claim 10 , wherein, when the uplink signal is a RACH, the determined uplink Tx power corresponds to the following equation F
P PRACH =min{ P CMAX,c ( i ),PREAMBLE_RECEIVED_TARGET_POWER+ PL c −offset BS — Diversity — margin } [Equation F]
wherein c indicates the index of the specific cell, i represents a subframe index, P PRACH is RACH Tx power in the subframe i of the specific cell c, PREAMBLE_RECEIVED_TARGET_POWER represents receive (Rx) power of a RACH preamble targeted by a BS, PL c is a downlink pathloss estimate calculated in dB by the terminal of the specific cell c, and offset BS — Diversity — margin is the offset value.