Method and apparatus for transmitting PPDU on basis of S-TDMA in wireless LAN system

A wireless device being an access point (AP) for transmitting a Physical layer Protocol Data Unit (PPDU) based on Scheduled-Time Division Multiple Access (S-TDMA) in a wireless LAN system, the wireless device comprising:

• a memory;
• a transceiver;
• and
• a processor being operatively coupled with the memory and the transceiver,
• wherein the processor:
• generates the PPDU, and
• transmits the PPDU to a first station (STA) and a second STA,
• wherein the PPDU includes a legacy header field, a first signal field, a second signal field, a first data field for the first STA, and a second data field for the second STA,
• wherein the second signal field includes information on Resource Unit (RU) layout and information on a number of STAs using the first RU,
• wherein, in case a third signal field is further included in the PPDU, the third signal field includes information on the S-TDMA,
• wherein the information on the S-TDMA includes S-TDMA indication information on that the S-TDMA can be performed, first symbol offset information for the first data field, and second symbol offset information for the second data field,
• wherein the S-TDMA indication information includes information on that the first and second data fields are being allocated to the first RU,
• wherein the first data field is transmitted in the first RU based on the first symbol offset information,
• wherein the second data field is transmitted in the first RU based on the second symbol offset information,
• wherein, in case a third signal field is not included in the DL PPDU, the second signal field further includes information on the S-TDMA,
• wherein the information on Resource Unit (RU) layout and the information on a number of STAs using the first RU are included in a common field of the second signal field, and
• wherein the information on the S-TDMA is included in a user field of the second signal field.

A method for receiving a Physical layer Protocol Data Unit (PPDU) based on Scheduled-Time Division Multiple Access (S-TDMA) in a wireless LAN system, the method comprising:

• receiving, by a first station (STA), the PPDU from an access point (AP), wherein the PPDU includes a first data field for the first STA and a second data field for the second STA;
• and
• decoding, by the first STA, the first data field,
• wherein the PPDU includes a legacy header field, a first signal field, and a second signal field,
• wherein the second signal field includes information on Resource Unit (RU) layout and information on a number of STAs using the first RU,
• wherein, in case a third signal field is further included in the PPDU, the third signal field includes information on the S-TDMA,
• wherein the information on the S-TDMA includes S-TDMA indication information on that the S-TDMA can be performed, first symbol offset information for the first data field, and second symbol offset information for the second data field,
• wherein the S-TDMA indication information includes information on that the first and second data fields are being allocated to the first RU,
• wherein the first data field is transmitted in the first RU based on the first symbol offset information,
• wherein the second data field is transmitted in the first RU based on the second symbol offset information,
• wherein, in case a third signal field is not included in the DL PPDU, the second signal field further includes information on the S-TDMA,
• wherein the information on Resource Unit (RU) layout and the information on a number of STAs using the first RU are included in a common field of the second signal field, and
• wherein the information on the S-TDMA is included in a user field of the second signal field.