Method and apparatus for transmitting data in wireless communication system

An access point (AP) associated with a first basic service set (BSS) in a wireless LAN (WLAN) system, comprising:

• a transceiver configured to transmit and receive radio signals;
• and
• a processor configured to control the transceiver to,
• transmit a trigger frame which requests uplink multi-user (UL MU) transmission of a plurality of stations (STAs),
• wherein the trigger frame includes SR indication information used for the SR of an overlapping BSS (OBSS) STA;
• receive an UL MU physical protocol data unit (PPDU) generated based on the trigger frame from the plurality of STAs,
• wherein the UL MU PPDU includes sequentially (i) a L (legacy)-preamble, (ii) a High Efficiency (HE)-preamble and (iii) a data field,
• wherein the HE-preamble includes sequentially (i) a first high efficiency (HE)-signal (SIG) A field, (ii) an HE-Short Training Field (STF) field, and (iii) an HE-Long Training Field (LTF) field,
• wherein a first Inverse Discrete Fourier Transform (IDFT)/Discrete Fourier Transform (DFT) period is applied from the L-preamble to the first HE-SIG A field and a second IDFT/DFT period is applied to the data field, and
• wherein the second IDFT/DFT period is 4 times of the first IDFT/DFT period;
• and
• wherein based on the AP being placed in an OBSS in which the first BSS and a second BSS overlap, the processor further configured to:
• receive a second HE-SIG A field of a PPDU transmitted by an STA placed in the second BSS;
• obtain SR support information of the second HE-SIG A field;
• and
• perform the SR based on the SR support information of the second HE-SIG A field,
• wherein the UL MU PPDU is transmitted on at least one of 20 MHz, 40 MHz and 80 MHz channels,
• wherein the first HE-SIG A field includes SR support information generated based on the SR indication information, and
• wherein the SR support information comprises SR permission information of the OBSS STA, transmission power information of the AP, and information about an interference level acceptable to the AP.

A method for indicating, by a station (STA) associated with a first basic service set (BSS), spatial reuse (SR) in a wireless LAN (WLAN) system, the method comprising:

• receiving a trigger frame which requests uplink multi-user (UL MU) transmission of a plurality of stations (STAs),
• wherein the trigger frame includes SR indication information used for the SR of an overlapping BSS (OBSS) STA;
• transmitting an UL MU physical protocol data unit (PPDU) generated based on the trigger frame from the plurality of STAs,
• wherein the UL MU PPDU includes sequentially (i) a L (legacy)-preamble, (ii) a High Efficiency (HE)-preamble and (iii) a data field,
• wherein the HE-preamble includes sequentially (i) a first high efficiency (HE)-signal (SIG) A field, (ii) an HE-Short Training Field (STF) field, and (iii) an HE-Long Training Field (LTF) field,
• wherein a first Inverse Discrete Fourier Transform (IDFT)/Discrete Fourier Transform (DFT) period is applied from the L-preamble to the first HE-SIG A field and a second IDFT/DFT period is applied to the data field, and
• wherein the second IDFT/DFT period is 4 times of the first IDFT/DFT period;
• and
• wherein based on the AP being placed in an OBSS in which the first BSS and a second BSS overlap, further comprising:
• transmitting a second HE-SIG A field of a PPDU including SR support information;
• and
• performing the SR based on the SR support information of the second HE-SIG A field,
• wherein the UL MU PPDU is transmitted on at least one of 20 MHz, 40 MHz and 80 MHz channels,
• wherein the first HE-SIG A field includes SR support information generated based on the SR indication information, and
• wherein the SR support information comprises SR permission information of the OBSS STA, transmission power information of the AP, and information about an interference level acceptable to the AP.