Method and apparatus for uplink transmissions in frame-based equipment NR unlicensed
Methods and apparatuses of a BSs and UEs in a wireless communication system are provided. A method of operating the UE comprises: receiving, from a BS over a shared spectrum channel, a first DCI including a COT of the BS; determining a first portion of the COT for a downlink transmission from the BS and a second portion of the COT for an uplink transmission to the BS, wherein the COT includes a gap between the first and second portions of the COT; performing a channel access procedure based on a duration of the gap; receiving the downlink transmission in the first portion of the COT; and transmitting the uplink transmission in the second portion of the COT based on a sensing status of the shared spectrum channel that is sensed as an idle state during the channel access procedure in the duration of the gap.
1. A user equipment (UE) in a wireless communication system, the UE comprising:
a transceiver configured to receive, from a base station (BS), first downlink control information (DCI) including a channel occupancy time (COT) of the BS; and
a processor operably connected to the transceiver, the processor configured to:
determine a first portion of the COT for a downlink transmission from the BS and a second portion of the COT for an uplink transmission to the BS, wherein the COT includes a gap between the first and second portions of the COT;
identify an operation mode of the BS, wherein the operation mode of the BS is a semi-static mode including a period, before starting the COT, during which transmissions are not allowed; and
perform a channel access procedure based on a duration of the gap,
wherein the transceiver is further configured to:
receive, from the BS over a shared spectrum channel, the downlink transmission in the first portion of the COT, and
transmit, to the BS over the shared spectrum channel, the uplink transmission in the second portion of the COT, if the shared spectrum channel is sensed as an idle state during the channel access procedure performed in the duration of the gap.
2. The UE of claim 1 , wherein the channel access procedure does not include a time duration for sensing the shared spectrum channel if the duration of the gap is no longer than 16 microseconds.
3. The UE of claim 1 , wherein the channel access procedure includes a time duration of 16 microseconds for sensing the shared spectrum channel, if the duration of the gap is longer than 16 microseconds.
4. The UE of claim 1 , wherein the processor is further configured to determine that a physical random access channel (PRACH) occasion is valid, if the PRACH occasion does not overlap with the period.
5. The UE of claim 1 , wherein:
the processor is further configured to determine second DCI from the downlink transmission included in the first portion of the COT; and
the second DCI includes a type of channel access operation for the uplink transmission included in the second portion of the COT.
6. The UE of claim 5 , wherein the type of channel access operation is one of:
a type of channel access procedure not including a time duration for sensing the shared spectrum channel; or
a type of channel access procedure including a time duration of 16 microseconds for sensing the shared spectrum channel.
7. A base station (BS) in a wireless communication system, the BS comprising:
a processor configured to:
determine a first portion of channel occupancy time (COT) for a downlink transmission to a user equipment (UE) and a second portion of the COT for an uplink transmission from the UE, wherein the COT includes a gap between the first and second portions of the COT,
identify an operation mode of the BS, wherein the operation mode of the BS is a semi-static mode including a period, before starting the COT, during which transmissions are not allowed; and
a transceiver operably connected to the processor, the transceiver configured to:
transmit, to the UE, first downlink control information (DCI) including the COT of the BS,
transmit, to the UE over a shared spectrum channel, the downlink transmission in the first portion of the COT, and
receive, from the UE over the shared spectrum channel, the uplink transmission in the second portion of the COT, if the shared spectrum channel is sensed as an idle state during a channel access procedure that is performed based on a duration of the gap.
8. The BS of claim 7 , wherein the channel access procedure does not include a time duration for sensing the shared spectrum channel if the duration of the gap is no longer than 16 microseconds.
9. The BS of claim 7 , wherein the channel access procedure includes a time duration of 16 microseconds for sensing the shared spectrum channel if the duration of the gap is longer than 16 microseconds.
10. The BS of claim 7 , wherein a physical random access channel (PRACH) occasion is valid, if the PRACH occasion does not overlap with the period.
11. The BS of claim 7 , wherein:
the processor is further configured to generate second DCI to be transmitted in the downlink transmission included in the first portion of the COT; and
the second DCI includes a type of channel access operation for the uplink transmission included in the second portion of the COT.
12. The BS of claim 11 , wherein the type of channel access operation is one of:
a type of channel access procedure not including a time duration for sensing the shared spectrum channel; or
a type of channel access procedure including a time duration of 16 microseconds for sensing the shared spectrum channel.
13. A method of a user equipment (UE) in a wireless communication system, the method comprising:
receiving, from a base station (BS), first downlink control information (DCI) including a channel occupancy time (COT) of the BS;
determining a first portion of the COT for a downlink transmission from the BS and a second portion of the COT for an uplink transmission to the BS, wherein the COT includes a gap between the first and second portions of the COT;
identifying an operation mode of the BS, wherein the operation mode of the BS is a semi-static mode including a period, before starting the COT, during which transmissions are not allowed;
performing a channel access procedure based on a duration of the gap;
receiving, from the BS over the shared spectrum channel, the downlink transmission in the first portion of the COT; and
transmitting, to the BS over the shared spectrum channel, the uplink transmission in the second portion of the COT based on a sensing status of the shared spectrum channel that is sensed as an idle state during the channel access procedure performed in the duration of the gap.
14. The method of claim 13 , wherein the channel access procedure includes a time duration for sensing the shared spectrum channel, when the duration of the gap is longer than 16 microseconds.
15. The method of claim 13 , wherein the channel access procedure includes a time duration of 16 microseconds for sensing the shared spectrum channel, the duration of the gap being longer than 16 microseconds.
16. The method of claim 13 , further comprising determining that a physical random access channel (PRACH) occasion is valid, wherein the PRACH occasion does not overlap with the period.
17. The method of claim 13 , further comprising determining second DCI from the downlink transmission included in the first portion of the COT,
wherein:
the second DCI includes a type of channel access operation for the uplink transmission included in the second portion of the COT; and
the type of channel access operation is one of:
a type of channel access procedure not including a time duration for sensing the shared spectrum channel, or
a type of channel access procedure including a time duration of 16 microseconds for sensing the shared spectrum channel.