Channel occupancy time for sidelink communication in unlicensed band
Embodiments of the present disclosure relate to devices, methods, apparatuses and computer readable storage media of Channel Occupancy Time (COT) for Sidelink (SL) communication in Unlicensed band (U-band). The method includes receiving, at a first device and from a second device, configuration information associated with a COT at least for a SL transmission of the first device on an unlicensed resource pool allocated for the first device, the configuration information at least indicating whether a listen before talk procedure is required to be performed at the first device within the COT before the SL transmission; and performing the SL transmission within the COT based on the configuration information. In this way, the COT sharing mechanism can be used for SL communications in U-band and therefore a sensing procedure for resource selection may not be impacted by the LBT procedure.
1 . A first device, comprising:
at least one processor; and
at least one non-transitory memory storing instructions that, when executed by the at least one processor, cause the first device at least to:
receive, from a second device via a Layer 1 signal using preconfigured resource in an unlicensed band, configuration information associated with a channel occupancy time at least for a sidelink transmission of the first device on an unlicensed resource pool allocated for the first device, the configuration information at least indicating whether a listen before talk procedure is required within the channel occupancy time before the sidelink transmission, wherein the configuration information comprises:
a duration of the channel occupancy time,
a first remaining duration of the channel occupancy time, the first remaining duration starting from a time point at which the configuration information is received to an end of the channel occupancy time, and
a second remaining duration of the channel occupancy time, the second remaining duration starting from a time point at which the sidelink transmission starts to the end of the channel occupancy time; and
based on the configuration information, perform the sidelink transmission within the channel occupancy time before the sidelink transmission by:
in response to a determination, based on the configuration information, that the listen before talk procedure is required, determining, at least based on a sidelink control information, whether a time interval having a duration exceeding a threshold duration of 16 μs is detected within the channel occupancy time before the sidelink transmission of the first device, wherein neither the sidelink transmission nor a signal indicating or occupying the channel occupancy time is scheduled during the time interval;
based on determining that the time interval is detected within the channel occupancy time before the sidelink transmission, performing the listen before talk procedure before the sidelink transmission and within the channel occupancy time; and
based on determining that the listen before talk procedure is successful, performing the sidelink transmission on frequency-domain resources of the unlicensed resource pool that are different from frequency-domain resources used for transmitting the configuration information.
2 . A second device, comprising:
at least one processor; and
at least one non-transitory memory storing instructions that, when executed by the at least one processor, cause the second device at least to:
determine a channel occupancy time at least for a sidelink transmission of a first device on an unlicensed resource pool allocated for the first device;
generate configuration information associated with the channel occupancy time, the configuration information at least indicating whether a listen before talk procedure is required to be performed at the first device within the channel occupancy time before the sidelink transmission, wherein the configuration information comprises:
a duration of the channel occupancy time,
a first remaining duration of the channel occupancy time, the first remaining duration starting from a time point at which the configuration information is received to an end of the channel occupancy time, and
a second remaining duration of the channel occupancy time, the second remaining duration starting from a time point at which the sidelink transmission starts to the end of the channel occupancy time;
transmit the configuration information to the first device; and
based on receiving an indication of a time interval from the first device, transmit a signal occupying the channel occupancy time during the time interval having a duration exceeding a threshold duration of 16 μs within the channel occupancy time, wherein neither a sidelink transmission nor a signal to be transmitted for indicating or occupying the channel occupancy time is scheduled during the time interval.
3 . The second device of claim 2 , wherein the instructions, when executed by the at least one processor, cause the second device to transmit the configuration information by:
transmitting the configuration information based on at least one of:
a physical layer message,
a physical layer signal, and
a higher-layer message.
4 . The second device of claim 3 , wherein the instructions, when executed by the at least one processor, cause the second device to:
in response to a determination that the listen before talk procedure is not required to be performed at the first device within the channel occupancy time before the sidelink transmission, transmit a signal for occupying the channel occupancy time on a duration of the channel occupancy time.
5 . The second device of claim 4 , wherein the instructions, when executed by the at least one processor, cause the second device to:
in response to a determination that the listen before talk procedure is not required to be performed at the first device within the channel occupancy time before the sidelink transmission, determine whether a time interval having a duration exceeding a threshold duration is detected within the channel occupancy time, where neither sidelink transmission nor a signal to be transmitted for indicating or occupying the channel occupancy time is scheduled during the time interval; and
based on determining that the time interval is detected, transmit a signal occupying the channel occupancy time during the time interval.
6 . A method, comprising:
receiving, at a first device and from a second device, configuration information associated with a channel occupancy time at least for a sidelink transmission of the first device on an unlicensed resource pool allocated for the first device, the configuration information at least indicating whether a listen before talk procedure is required to be performed at the first device within the channel occupancy time before the sidelink transmission, wherein the configuration information comprises: a duration of the channel occupancy time,
a first remaining duration of the channel occupancy time, the first remaining duration starting from a time point at which the configuration information is received to an end of the channel occupancy time, and
a second remaining duration of the channel occupancy time, the second remaining duration starting from a time point at which the sidelink transmission starts to the end of the channel occupancy time; and
based on the configuration information, performing the sidelink transmission within the channel occupancy time, by:
in response to a determination, based on the configuration information, that the listen before talk procedure is required, determining, at least based on a sidelink control information, whether a time interval having a duration exceeding a threshold duration of 16 μs is detected within the channel occupancy time before the sidelink transmission of the first device, wherein neither the sidelink transmission nor a signal indicating or occupying the channel occupancy time is scheduled during the time interval:
based on determining that the time interval is detected within the channel occupancy time before the sidelink transmission, performing the listen before talk procedure before the sidelink transmission and within the channel occupancy time; and
based on determining that the listen before talk procedure is successful, performing the sidelink transmission on frequency-domain resources of the unlicensed resource pool that are different from frequency-domain resources used for transmitting the configuration information.
7 . A non-transitory program storage device readable with an apparatus, tangibly embodying a program of instructions executable with the apparatus for performing the method of claim 6 .