Method for transmitting data in wireless communication system and apparatus therefor

A station (STA) apparatus performing uplink (UL) multi-user (MU) transmission in a wireless communication system, the STA apparatus comprising:

• a radio frequency (RF) unit configured to transmit/receive radio signals;
• and
• a processor configured to control the RF unit,
• wherein the processor is configured to:
• receive a trigger frame comprising information for the UL MU transmission and an indicator indicating whether or not to execute carrier sensing,
• wherein the processor is further configured to:
• if the indicator indicates executing the carrier sensing, execute the carrier sensing on a specific channel, consider a result of the carrier sensing, and transmit a UL MU frame in response to the trigger frame;
• and
• if the indicator indicates not executing the carrier sensing, transmit the UL MU frame in response to the trigger frame without the carrier sensing,
• wherein, when considering the result of the carrier sensing, the processor is further configured to:
• if the specific channel is considered idle as a result of considering both a channel clear assessment (CCA) and a network allocation vector (NAV), transmit the UL MU frame through the specific channel;
• and
• if the specific channel is considered busy as the result of considering both the CCA and the NAV, not transmit the UL MU frame through the specific channel,
• wherein the NAV indicates idle when a NAV count value is nonzero and a non-bandwidth signaling transmitter address (TA) field is same as an address of a transmission opportunity (TXOP) holder, and
• wherein the CCA indicates busy when a detected energy level through energy detection exceeds a threshold.