Wireless communication terminal and wireless communication method for multiuser EDCA operation

1. A wireless communication terminal, the terminal comprising:

a communication unit; and

a processor configured to control transmission and reception of a wireless signal through the communication unit,

wherein the processor is configured to:

receive a first frame including at least one of an enhanced distributed channel access (EDCA) parameter set and a multi-user (MU) EDCA parameter set,

wherein the MU EDCA parameter set includes a first update count subfield indicating whether MU EDCA parameters of the MU EDCA parameter set are changed,

transmit a frame including operation mode indication (OMI) information,

update EDCA parameters for channel access according to a parameter set selected among the EDCA parameter set or the MU EDCA parameter set based on a value of the first update count subfield, and

perform the channel access based on the updated EDCA parameters for the channel access,

wherein the EDCA parameters are updated based on the EDCA parameter set or the MU EDCA parameter set after an immediate response to the OMI information is received when the OMI information indicates that the terminal does not participate in an uplink multi-user (MU) operation.

2. The wireless communication terminal of claim 1 ,

wherein the MU EDCA parameter set include a MU EDCA timer indicating a duration in which the MU EDCA parameters are used, and

wherein the MU EDCA timer included in the EDCA parameters for the channel access is set using the MU EDCA parameters of the MU EDCA parameter set, when the EDCA parameters for the channel access are updated based on the MU EDCA parameter set.

3. The wireless communication terminal of claim 1 , wherein the processor is configured to,

compare the value of the first update count subfield and a value of a second update count subfield stored in the terminal,

wherein the EDCA parameters for the channel access are updated the MU EDCA parameters of the MU EDCA parameter set when the value of the first update count subfield and the value of the second update count subfield are different.

4. The wireless communication terminal of claim 1 ,

wherein the value of the first update count subfield is increased when the MU EDCA parameters of the MU EDCA parameter set is changed.

5. The wireless communication terminal of claim 1 ,

wherein the OMI information includes a first subfield related to whether the terminal participates in the uplink MU operation,

wherein a MU EDCA timer included in the EDCA parameters for the channel access is set to zero when an immediate acknowledgment for the frame containing the OMI information is received.

6. The wireless communication terminal of claim 1 ,

wherein the OMI information includes a disable subfield indicating whether the terminal participates in the MU operation, and

wherein the EDCA parameters are updated after the immediate response to the OMI information including the disable subfield indicating that the terminal does not participate in the MU operation is received.

7. A wireless communication method of a wireless communication terminal, the method comprising:

receiving a first frame including at least one of an enhanced distributed channel access (EDCA) parameter set and a multi-user (MU) EDCA parameter set,

wherein the MU EDCA parameter set includes a first update count subfield indicating whether MU EDCA parameters of the MU EDCA parameter set are changed;

transmitting a frame including operation mode indication (OMI) information,

updating EDCA parameters for channel access according to a parameter set selected among the EDCA parameter set or the MU EDCA parameter set based on a value of the first update count subfield; and

performing the channel access based on the updated EDCA parameters for the channel access,

wherein the EDCA parameters are updated based on the EDCA parameter set or the MU EDCA parameter set after an immediate response to the OMI information is received when the OMI information indicates that the terminal does not participate in an uplink multi-user (MU) operation.

8. The wireless communication method of claim 7 ,

wherein the MU EDCA parameter set include a MU EDCA timer indicating a duration in which the MU EDCA parameters are used, and

wherein the MU EDCA timer included in the EDCA parameters for the channel access is set using the MU EDCA parameters of the MU EDCA parameter set, when the EDCA parameters for the channel access are updated based on the MU EDCA parameter set.

9. The wireless communication method of claim 7 , the method further comprising:

comparing the value of the first update count subfield and a value of a second update count subfield stored in the terminal,

wherein the EDCA parameters for the channel access are updated the MU EDCA parameters of the MU EDCA parameter set when the value of the first update count subfield and the value of the second update count subfield are different.

10. The wireless communication method of claim 7 ,

wherein the value of the first update count subfield is increased when the MU EDCA parameters of the MU EDCA parameter set is changed.

11. The wireless communication method of claim 7 ,

wherein the OMI information includes a first subfield related to whether the terminal participates in the uplink MU operation,

wherein a MU EDCA timer included in the EDCA parameters for the channel access is set to zero when an immediate acknowledgment for the frame containing the OMI information is received.

12. The wireless communication method of claim 7 ,

wherein the OMI information includes a disable subfield indicating whether the terminal participates in the MU operation, and

wherein the EDCA parameters are updated after the immediate response to the OMI information including the disable subfield indicating that the terminal does not participate in the MU operation is received.