Method of controlling transmit power of uplink channel in wireless communication system and apparatus therefor
A method for a user equipment to control transmit power of an uplink channel in a wireless communication system is disclosed in the present invention. The method includes the steps of setting a power control parameter to each of a plurality of power control processes, selecting a specific beam from among a plurality of beams, determining a specific power control process corresponding to the selected specific beam from among a plurality of the power control processes, adjusting transmit power of each of a plurality of symbols for the uplink channel according to a power control parameter set to the specific power control process, and transmitting the uplink channel to an eNB according to the adjusted transmit power.
1. A method of transmitting an uplink channel, by a user equipment (UE) in a wireless communication system, the method comprising:
configuring a plurality of power control parameters to each of a plurality of power control processes;
configuring energy per resource element (EPRE) ratio for each of a plurality of the symbols for the uplink channel,
wherein the EPRE ratio is a ratio between EPRE of a first resource element for a data and EPRE of a second resource element for a reference signal included in the uplink channel;
determining a specific power control process related to a specific beam among the plurality of the power control processes;
determining a first transmit power of the first resource element included in each symbol based on the power control parameter configured to the specific power control process;
determining a second transmit power of the second resource element included in each symbol based on the EPRE ratio and the first transmit power of the first resource element; and
transmitting, to a base station, the uplink channel based on the first and second transmit powers.
2. The method of claim 1 , wherein if EPRE ratio for a specific symbol is changed by power adjustment performed on the first resource element, a change of the EPRE ratio is determined as invalid and transmission of the uplink channel is dropped.
3. The method of claim 1 , wherein when a specific EPRE ratio is changed among EPRE ratios set to a plurality of the symbols, the specific EPRE ratio is changed to one EPRE ratio of EPRE ratio candidates configured by downlink control information (DCI).
4. The method of claim 1 , wherein the EPRE ratio is configured differently for each symbol according to a reference signal density of each of the plurality of symbols.
5. The method of claim 1 , wherein the first and second transmit powers of each of a plurality of the symbols is adjusted based on the same scaling coefficient.
6. A user equipment (UE) for transmitting an uplink channel in a wireless communication system, the UE comprising:
a transmitter and a receiver; and
a processor operatively coupled to the transmitter and the receiver, wherein the processor is configured to:
configure a plurality of power control parameters to each of a plurality of power control processes;
configure energy per resource element (EPRE) ratio for each of a plurality of the symbols for the uplink channel,
wherein the EPRE ratio is a ratio between EPRE of a first resource element for a data and EPRE of a second resource element for a reference signal included in the uplink channel;
determine a specific power control process related to a specific beam among the plurality of the power control processes;
determine a first transmit power of the first resource element included in each symbol based on the power control parameter configured to the specific power control process;
determine a second transmit power of the second resource element included in each symbol based on the EPRE ratio and the first transmit power of the first resource element; and
transmit the uplink channel based on the first and second transmit powers.
7. The UE of claim 6 , wherein if EPRE ratio for a specific symbol is changed by power adjustment performed on the first resource element, a change of the EPRE ratio is determined as invalid and transmission of the uplink channel is dropped.
8. The UE of claim 6 , wherein when a specific EPRE ratio is changed among EPRE ratios set to a plurality of the symbols, the specific EPRE ratio is changed to one EPRE ratio of EPRE ratio candidates configured by downlink control information (DCI).
9. The UE of claim 6 , wherein the EPRE ratio is configured differently for each symbol according to a reference signal density of each of the plurality of symbols.
10. The UE of claim 6 , wherein the first and second transmit powers of each of a plurality of the symbols is adjusted based on the same scaling coefficient.