Method and device for configuring spatial reuse field in wireless lan system

A first station (STA) in a wireless local area network (WLAN) system, the first STA comprising:

• a memory;
• a transceiver;
• and
• a processor being operatively connected to the memory and the transceiver,
• wherein the processor is configured to:
• receive a trigger frame soliciting a Trigger Based Physical Protocol Data Unit (TB PPDU) from a second STA;
• and
• transmit the TB PPDU to the second STA,
• wherein the trigger frame includes a common information field and a special user information field,
• wherein the common information field includes an uplink (UL) spatial reuse field comprising first to fourth spatial reuse subfields,
• wherein the special user information field includes first and second extreme high throughput (EHT) spatial reuse subfields,
• wherein based on the trigger frame soliciting a 20 MHz TB PPDU, each of the first to fourth spatial reuse subfields is set to a value of the first EHT spatial reuse subfield,
• wherein based on the trigger frame soliciting a 40 MHz TB PPDU, the first and third spatial reuse subfields are set to the value of the first EHT spatial reuse subfield, and the second and fourth spatial reuse subfields are set to a value of the second EHT spatial reuse subfield,
• wherein based on the trigger frame soliciting an 80 MHz TB PPDU or a 160 MHz TB PPDU, the first and second spatial reuse subfields are set to the value of the first EHT spatial reuse subfield, and the third and fourth spatial reuse subfields are set to the value of the second EHT spatial reuse subfield,
• wherein based on the trigger frame soliciting a 320 MHz TB PPDU, each of the first to fourth spatial reuse subfields is set to a smaller of the values of the first and second EHT spatial reuse subfields,
• wherein the first to fourth spatial reuse subfields each consist of 4 bits, and
• wherein the first and second EHT spatial reuse subfields each consist of 4 bits.

A method in a wireless local area network (WLAN) system, the method comprising:

• transmitting, by a second station (STA), a trigger frame soliciting a Trigger Based Physical Protocol Data Unit (TB PPDU) to a first STA;
• and
• receiving, by the second STA, the TB PPDU from the first STA,
• wherein the trigger frame includes a common information field and a special user information field,
• wherein the common information field includes an uplink (UL) spatial reuse field comprising first to fourth spatial reuse subfields,
• wherein the special user information field includes first and second extreme high throughput (EHT) spatial reuse subfields,
• wherein based on the trigger frame soliciting a 20 MHz TB PPDU, each of the first to fourth spatial reuse subfields is set to a value of the first EHT spatial reuse subfield,
• wherein based on the trigger frame soliciting a 40 MHz TB PPDU, the first and third spatial reuse subfields are set to the value of the first EHT spatial reuse subfield, and the second and fourth spatial reuse subfields are set to a value of the second EHT spatial reuse subfield,
• wherein based on the trigger frame soliciting an 80 MHz TB PPDU or a 160 MHz TB PPDU, the first and second spatial reuse subfields are set to the value of the first EHT spatial reuse subfield, and the third and fourth spatial reuse subfields are set to the value of the second EHT spatial reuse subfield,
• wherein based on the trigger frame soliciting a 320 MHz TB PPDU, each of the first to fourth spatial reuse subfields is set to a smaller of the values of the first and second EHT spatial reuse subfields,
• wherein the first to fourth spatial reuse subfields each consist of 4 bits, and
• wherein the first and second EHT spatial reuse subfields each consist of 4 bits.

A second station (STA) in a wireless local area network (WLAN) system, the second STA comprising:

• a memory;
• a transceiver;
• and
• a processor being operatively connected to the memory and the transceiver,
• wherein the processor is configured to:
• transmit a trigger frame soliciting a Trigger Based Physical Protocol Data Unit (TB PPDU) to a first STA;
• and
• receive the TB PPDU from the first STA,
• wherein the trigger frame includes a common information field and a special user information field,
• wherein the common information field includes an uplink (UL) spatial reuse field comprising first to fourth spatial reuse subfields,
• wherein the special user information field includes first and second extreme high throughput (EHT) spatial reuse subfields,
• wherein based on the trigger frame soliciting a 20 MHz TB PPDU, each of the first to fourth spatial reuse subfields is set to a value of the first EHT spatial reuse subfield,
• wherein based on the trigger frame soliciting a 40 MHz TB PPDU, the first and third spatial reuse subfields are set to the value of the first EHT spatial reuse subfield, and the second and fourth spatial reuse subfields are set to a value of the second EHT spatial reuse subfield,
• wherein based on the trigger frame soliciting an 80 MHz TB PPDU or a 160 MHz TB PPDU, the first and second spatial reuse subfields are set to the value of the first EHT spatial reuse subfield, and the third and fourth spatial reuse subfields are set to the value of the second EHT spatial reuse subfield,
• wherein based on the trigger frame soliciting a 320 MHz TB PPDU, each of the first to fourth spatial reuse subfields is set to a smaller of the values of the first and second EHT spatial reuse subfields,
• wherein the first to fourth spatial reuse subfields each consist of 4 bits, and
• wherein the first and second EHT spatial reuse subfields each consist of 4 bits.