Method and device for transmitting uplink signal in wireless communication system
The present invention relates to a wireless communication system, particularly, a method comprising: adjusting transmission power of one or more cells within a first cell group such that transmission power of the first cell group does not exceed a maximum power value set in the first group; adjusting transmission power of one or more cells within a second cell group such that transmission power of the second cell group does not exceed a maximum power value set in the second group; additionally reducing the transmission power of the first cell group and the second cell group if total transmission power of the whole cell group including the first cell group and the second cell group exceeds a maximum power value set in the terminal; and performing uplink transmission in the first cell group and the second cell group by using the additionally reduced transmission power, and a device therefore.
1. A method of controlling uplink power, which is controlled by a user equipment in a wireless communication system, the method comprising:
adjusting transmit power of at least one or more cells belonging to a first cell group to keep a transmit power of the first cell group from exceeding a maximum power limit set to the first cell group;
adjusting transmit power of at least one or more cells belonging to a second cell group to keep a transmit power of the second cell group from exceeding a maximum power limit set to the second cell group;
when total transmit power of all cell groups containing the first cell group and the second cell group exceeds a maximum power limit set to the user equipment, additionally reducing the transmit power of the first cell group and the transmit power of the second cell group; and
performing uplink transmission in the first cell group and the second cell group using the additionally reduced transmit power,
wherein the transmit power of the first cell group and the transmit power of the second cell group are reduced using a scaling factor per cell group, and
wherein the scaling factor per cell group is configured in proportion to a number of cells belonging to each cell group.
2. The method of claim 1 , wherein the scaling factor per cell group is configured in proportion to a number of activated cells among a plurality of cells constructing each cell group.
3. The method of claim 1 , wherein the transmit power of the first cell group is additionally reduced so as to be equal to or less than a value determined as follows:
(P cg-1 /P cg-sum )×P ue-max ,
where, P cg-1 corresponds to the transmit power of the first cell group, P cg-sum corresponds to the total transmit power of all cell groups, and P ue-max corresponds to the maximum power limit set to the user equipment.
4. The method of claim 1 , wherein at least one of the first cell group and the second cell group comprises a plurality of cells.
5. A user equipment configured to control uplink power in a wireless communication system, the user equipment comprising:
a radio frequency (RF) unit; and
a processor configured to:
adjust transmit power of at least one or more cells belonging to a first cell group to keep a transmit power of the first cell group from exceeding a maximum power limit set to the first cell group,
adjust transmit power of at least one or more cells belonging to a second cell group to keep a transmit power of the second cell group from exceeding a maximum power limit set to the second cell group,
when total transmit power of all cell groups containing the first cell group and the second cell group exceeds a maximum power limit set to the user equipment, additionally reduce the transmit power of the first cell group and the transmit power of the second cell group, and
control the RF unit to perform uplink transmission in the first cell group and the second cell group using the additionally reduced transmit power,
wherein the transmit power of the first cell group and the transmit power of the second cell group are reduced using a scaling factor per cell group, and
wherein the scaling factor per cell group is configured in proportion to a number of cells belonging to each cell group.
6. The user equipment of claim 5 , wherein the scaling factor per cell group is configured in proportion to a number of activated cells among a plurality of cells constructing each cell group.
7. The user equipment of claim 5 , wherein the transmit power of the first cell group is additionally reduced so as to be equal to or less than a value determined as follows:
(P cg-1 /P cg-sum )×P ue-max ,
where, P cg-1 corresponds to the transmit power of the first cell group, P cg-sum corresponds to the total transmit power of all cell groups, and P ue-max corresponds to the maximum power limit set to the user equipment.
8. The user equipment of claim 5 , wherein at least one of the first cell group and the second cell group comprises a plurality of cells.