Method and apparatus for transmitting data frame in WLAN system

A station configured to transmit a data frame in a wireless local area network, the station comprising:

• a transceiver;
• and
• a processor operatively connected to the transceiver and configured to:
• control the transceiver to obtain a transmission opportunity (TXOP) for a bandwidth, the TXOP indicating an interval of time during which the station has a right to initiate frame exchange sequences onto wireless medium;
• set a transmit bandwidth parameter of a non-initial physical layer protocol data unit (PPDU) of a plurality of PPDUs to be transmitted during the TXOP based on a transmit bandwidth parameter of a preceding PPDU of the plurality of PPDUs, wherein the transmit bandwidth parameter of the non-initial PPDU is set to be narrower than the transmit bandwidth parameter of the preceding PPDU, wherein a bandwidth indicated by the transmit bandwidth parameter of the non-initial PPDU or the preceding PPDU includes at least one of 20 MHz, 40 MHz and 80 MHz;
• and
• control the transceiver to transmit, during the TXOP, the non-initial PPDU according to the transmit bandwidth parameter of the PPDU.