Method of transmitting uplink signal from user equipment in a wireless communication system supporting unlicensed band and apparatus supporting the same
Disclosed herein is a method of transmitting a UL signal from a user equipment (UE) in a wireless communication system supporting an unlicensed band and apparatuses for supporting the same. More specifically, the present invention provides an embodiment in which the UE performs autonomous uplink transmission and scheduled uplink transmission through the unlicensed band, a method of adjusting contention window size when the UE perform the autonomous uplink transmission through the unlicensed band, and an embodiment of performing the autonomous uplink transmission based on the method.
1. A method performed by a user equipment (UE) operating in a wireless communication system, the method comprising:
performing an autonomous uplink (AUL) transmission starting before time unit n using a channel access procedure (CAP) on a unlicensed band, wherein n is an integer; and
performing a scheduled uplink (SUL) transmission starting from the time unit n on the unlicensed band,
wherein depending on whether a priority class value for channel access for the AUL transmission is equal to or larger than a priority class value for channel access for the SUL transmission, the SUL transmission starts from the time unit n either without a gap or with a gap after the AUL transmission, such that:
based on the priority class value for channel access for the AUL transmission not being equal to or larger than the priority class value for channel access for the SUL transmission: the AUL transmission is terminated, while the AUL transmission is ongoing and before the AUL transmission ends, with the gap before the time unit n at which the SUL transmission starts.
2. The method of claim 1 , wherein the time unit n is one of:
a first time unit where a first time interval configured for the AUL transmission overlaps with a second time interval scheduled for the SUL transmission, or
a second time unit following a third time unit configured for the AUL transmission.
3. The method of claim 1 , wherein the gap comprises one or more symbols.
4. The method of claim 1 , wherein based on the priority class value for channel access for the AUL transmission being equal to or larger than the priority class value for channel access for the SUL transmission: the SUL transmission starts from the time unit n without the gap after the AUL transmission ends such that the SUL transmission is performed without the CAP for the SUL transmission.
5. The method of claim 1 , wherein the AUL transmission is activated based on a first downlink control information (DCI), and
wherein the AUL transmission is released based on a second DCI.
6. The method of claim 5 , wherein the first DCI is distinguished from the second DCI based on a value of a first field of the first DCI and a value of a first field of the second DCI, and
wherein the first field of the first DCI and the first field of the second DCI are timing offset fields.
7. The method of claim 6 , wherein a second field of the first DCI and a second field of the second DCI have an identical value, and
wherein a second field of a third DCI for acknowledgement of the AUL transmission has a different value from the second field of the first DCI and the second field of the second DCI.
8. The method of claim 7 , wherein the second field of the first DCI, the second field of the second DCI, and the second field of the third DCI are physical uplink shared channel (PUSCH) trigger A fields.
9. The method of claim 7 , wherein the first DCI, the second DCI and the third DCI have an identical size.
10. The method of claim 7 , wherein the first DCI, the second DCI and the third DCI are scrambled by a radio network temporary identifier (RNTI) different from a cell-RNTI (C-RNTI).
11. The method of claim 1 , wherein based on the priority class value for channel access for the AUL transmission being equal to or larger than the priority class value for channel access for the SUL transmission: the SUL transmission starts from the time unit n without the gap after the AUL transmission such that the SUL transmission starts from the time unit n without a listen-before-talk (LBT) gap after the AUL transmission.
12. The method of claim 1 , wherein a sum of a duration of the AUL transmission and a duration of the SUL transmission does not exceed a maximum channel occupancy time (MCOT) for the AUL transmission.
13. The method of claim 1 , wherein based on the priority class value for channel access for the AUL transmission being equal to or larger than the priority class value for channel access for the SUL transmission: the SUL transmission starts from the time unit n without gap after the AUL transmission ends.
14. A user equipment (UE) configured to operate in a wireless communication system, the UE comprising:
a transceiver;
at least one processor; and
at least one computer memory operably connectable to the at least one processor and storing instructions that, when executed by the at least one processor, perform operations comprising:
performing, through the transceiver, an autonomous uplink (AUL) transmission starting before time unit n using a channel access procedure (CAP) on a unlicensed band, wherein n is an integer; and
performing, through the transceiver, a scheduled uplink (SUL) transmission starting from the time unit n on the unlicensed band,
wherein depending on whether a priority class value for channel access for the AUL transmission is equal to or larger than a priority class value for channel access for the SUL transmission, the SUL transmission starts from the time unit n either without a gap or with a gap after the AUL transmission, such that:
based on the priority class value for channel access for the AUL transmission not being equal to or larger than the priority class value for channel access for the SUL transmission: the AUL transmission is terminated, while the AUL transmission is ongoing and before the AUL transmission ends, with the gap before the time unit n at which the SUL transmission starts.
15. A communication device configured to operate in a wireless communication system, the communication device comprising:
at least one processor; and
at least one memory operably connectable to the at least one processor and storing instructions that, when executed by the at least one processor, perform operations comprising:
performing an autonomous uplink (AUL) transmission starting before time unit n using a channel access procedure (CAP) on a unlicensed band, wherein n is an integer; and
performing a scheduled uplink (SUL) transmission starting from the time unit n on the unlicensed band,
wherein depending on whether a priority class value for channel access for the AUL transmission is equal to or larger than a priority class value for channel access for the SUL transmission, the SUL transmission starts from the time unit n either without a gap or with a gap after the AUL transmission, such that:
based on the priority class value for channel access for the AUL transmission not being equal to or larger than the priority class value for channel access for the SUL transmission: the AUL transmission is terminated, while the AUL transmission is ongoing and before the AUL transmission ends, with the gap before the time unit n at which the SUL transmission starts.