Wireless communication method using multiple links, and wireless communication terminal using same
An AP multi-link device is disclosed. The AP multi-link device comprises: a transceiver; and a processor. During reception at any one link, when performing transmission at the second link to a non-AP multi-link device operating at a first link and a second link, which are non-simultaneous transmit and receive (STR) links not supported for transmission at another link, the processor determines whether to perform transmission at the second link for the non-AP multi-link device based on whether the non-AP multi-link device is transmitting to the first link.
1 . An access point (AP) multi-link device comprising:
a transceiver; and
a processor,
wherein the processor is configured to:
when performing, on a second link, a transmission to a non-AP multi-link device, to determine whether to perform the transmission to the non-AP multi-link device on the second link, based on whether the non-AP multi-link device performs a transmission on a first link,
wherein the non-AP multi-link device operates on the first link and the second link corresponding to non-simultaneous transmit and receive (STR) links on which a transmission of the non-AP multi-link device on one of the first link and the second link is restricted for protecting a transmission or reception of the non-AP multi-link device on the other of the first link and the second link,
wherein in a channel access procedure on the second link the processor is further configured,
to acquire a random number within a contention window (CW) to configure the random number as an initial value of a backoff counter for the second link, and to decrease the backoff counter by 1 when it is detected that a channel of the second link is idle during a slot time, wherein the transmission of the AP multi-link device on the second link is not allowed when the backoff counter is not 0,
when the backoff counter is 0, not to perform the transmission on the second link while the non-AP multi-link device is performing the transmission on the first link, and
to maintain a value of the backoff counter as 0 and a value of the CW after the not performing the transmission.
2 . The AP multi-link device of claim 1 , wherein the processor is configured to perform a transmission to a device different from the non-AP multi-link device when the AP multi-link device does not perform the transmission to the non-AP multi-link device on the second link while the non-AP multi-link device performs the transmission on the first link.
3 . The AP multi-link device of claim 2 , wherein the processor is configured to, when performing the transmission to the device different from the non-AP multi-link device on the second link, transmit traffic having a priority equal to or higher than traffic of the transmission to the non-AP multi-link device on the second link.
4 . The AP multi-link device of claim 1 , wherein the processor is configured to perform synchronized transmission on the first link and the second link, wherein the synchronized transmissions end with a time difference within a first predetermined time interval, and
receive a transmission following the synchronized transmissions on at least one of the first link and the second link,
wherein an interval between the following transmission and the synchronized transmissions performed on a link on which the following transmission is performed is a sum of a short inter-frame space (SIFS) and the first predetermined time interval.
5 . The AP multi-link device of claim 1 , wherein
the processor is configured to, if a channel of the second link is idle for a second predetermined time interval when the backoff counter is 0, a perform transmissions on the first link and the second link.
6 . The AP multi-link device of claim 5 , wherein the processor is configured to, if the channel of the first link is idle for the second predetermined time interval when the backoff counter is 0, start the transmission with a time difference within a third predetermined time interval on the first link and the second link.
7 . A non-access point (AP) multi-link device comprising:
a transceiver; and
a processor,
wherein the non-AP multi-link device is configured to operate on a first link and a second link corresponding to non-simultaneous transmit and receive (STR) links on which transmission of the non-AP multi-link device on one link is restricted for protecting transmission or reception of the non-AP multi-link device on another link, and
the processor is configured: to acquire a random number within a contention window, CW, for the second link, to configure the random number as an initial value of a backoff counter, to decrease the backoff counter by 1 when it is detected that a channel of the second link is idle during a slot time, wherein a transmission of the non-AP multi-link device on the second link is not allowed when the backoff counter is not 0,
when the backoff counter is 0, not to perform the transmission on the second link while the non-AP multi-link device is performing reception on the first link, and to maintain a value of the backoff counter as 0 and a value of the CW after the not performing the transmission.
8 . The non-AP multi-link device of claim 7 , wherein the processor is configured to receive synchronized transmissions on the first link and the second link, wherein the synchronized transmissions on the first link and the second link with a time difference within a first predetermined time interval, and
perform transmission following the synchronized transmissions on at least one of the first link and the second link,
wherein an interval between the following transmission and the synchronized transmissions performed on a link on which the following transmission is performed is a sum of a short inter-frame space (SIFS) and the first predetermined time interval.
9 . The non-AP multi-link device of claim 7 , wherein, when a change in a frequency band of one of the first link and the second link is made, information on whether STR is supported is transmitted.
10 . The non-AP multi-link device of claim 2 ,
the processor is configured to perform transmissions to an AP multi-link device with a time difference within a second predetermined time interval on the first link and the second link if a channel of the first link is idle for a third predetermined time when the backoff counter is 0.
11 . A method of operating an access point (AP) multi-link device, the method comprising:
when performing a transmission to a non-AP multi-link device, determining whether to perform the transmission to the non-AP multi-link device on a second link, based on whether the non-AP multi-link device performs transmission on a first link, wherein the non-AP multi-link device operates on the first link and the second link corresponding to non-simultaneous transmit and receive (STR) links on which a transmission of the non-AP multi-link device on one of the first link and the second link is restricted for protecting a transmission or reception of the non-AP multi-link device on the other of the first link and the second link,
acquiring a random number within a contention window (CW),
configuring the random number as an initial value of a backoff counter for the second link, and
decreasing the backoff counter by 1 when it is detected that a channel of the second link is idle during a slot time, wherein the transmission of the AP multi-link device on the second link is not allowed when the backoff counter is not 0,
when the backoff counter is 0, not performing the transmission on the second link while the non-AP multi-link device is performing the transmission on the first link, and
maintaining a value of the backoff counter as 0 and a value of the CW after the not performing the transmission.
12 . The method of claim 11 , further comprising performing a transmission to a device different from the non-AP multi-link device when the AP multi-link device does not perform the transmission to the non-AP multi-link device on the second link while the non-AP multi-link device performs the transmission on the first link.
13 . The method of claim 12 , wherein the performing the transmission to the device different from the non-AP multi-link device further comprises, when transmission to the device different from the non-AP multi-link device is performed on the second link, transmitting traffic having a priority equal to or higher than traffic of the transmission to the non-AP multi-link device on the second link.
14 . The method of claim 11 , further comprising:
performing synchronized transmissions on the first link and the second link, wherein the synchronized transmissions end with a time difference within a first predetermined time interval, and
receiving a transmission following the synchronized transmissions from at least one of the first link and the second link,
wherein an interval between the following transmission and the synchronized transmissions performed on a link on which the following transmission is performed is a sum of a short inter-frame space (SIFS) and the first predetermined time interval.