Method and apparatus for determining channel access type in wireless communication system

1. A method performed by a terminalin a wireless communication system, the method comprising:

receiving, from a base station, a random access response (RAR) including an uplink grant for transmission of a message 3 (MSG3) associated with a random access procedure, the uplink grant including first information associated with a type for a first channel access procedure for the transmission of the MSG3;

performing the first channel access procedure based on the type identified by the first information;

transmitting, to the base station, the MSG3 associated with the random access procedure based on the first channel access procedure;

receiving, from the base station, downlink control information (DCI) scheduling a retransmission of the MSG3, the DCI including second information associated with a type for a second channel access procedure for the retransmission of the MSG3;

performing the second channel access procedure based on the type identified by the second information; and

transmitting, to the base station, the MSG3 based on the second channel access procedure.

2. The method of claim 1 , wherein the RAR further includes third information associated with a channel access priority class for the first channel access procedure, in case that the first information indicates a specific type for the first channel access procedure, and

wherein the first channel access procedure is performed based on the first information and the third information.

3. The method of claim 1 , wherein a cyclic redundancy check (CRC) for the DCI is scrambled by a temporary cell radio network temporary identifier (TC-RNTI) included in the RAR.

4. The method of claim 1 , further comprising:

receiving, from the base station, DCI scheduling another retransmission of the MSG3;

performing a third channel access procedure based on the type identified by the first information, in case that the DCI scheduling the another retransmission does not include information associated with a type for the third channel access procedure; and

transmitting, to the base station, the MSG3 based on the third channel access procedure.

5. The method of claim 1 , wherein the type for the first channel access procedure or the second channel access procedure includes a first type or a second type,

wherein the first type is performed by sensing a channel during a plurality of slot durations within a contention window, and

wherein the second type is performed by sensing the channel for a predetermined duration.

6. The method of claim 5 , wherein the type for the first channel access procedure or the second channel access procedure further includes a third type, and

wherein the third type is performed by not sensing the channel.

7. A method performed by a base station in a wireless communication system, the method comprising:

transmitting, to a terminal, a random access response (RAR) including an uplink grant for receiving a message 3 (MSG3) associated with a random access procedure, the uplink grant including first information associated with a type for a first channel access procedure for the transmission of the MSG3;

transmitting, to the terminal, downlink control information (DCI) scheduling a retransmission of the MSG3 in case that the transmission from the terminal of the MSG3 associated with the random access procedure based on the first channel access procedure is not received, the DCI including second information associated with a type for a second channel access procedure for the retransmission of the MSG3; and

receiving, from the terminal, the MSG3 based on the second channel access procedure, which is based on the type identified by the second information.

8. The method of claim 7 , wherein the RAR further includes third information associated with a channel access priority class for the first channel access procedure, in case that the first information indicates a specific type for the first channel access procedure, and

wherein the first channel access procedure is based on the first information and the third information.

9. The method of claim 7 ,

wherein a cyclic redundancy check (CRC) for the DCI is scrambled by a temporary cell radio network temporary identifier (TC-RNTI) included in the RAR.

10. The method of claim 7 , further comprising:

transmitting, to the terminal, DCI scheduling another retransmission of the MSG3 in case that the transmission of the MSG3 is not received; and

receiving, from the terminal, the MSG3 based on a third channel access procedure, which is based on the type identified by the first information, in case that the DCI scheduling the another retransmission does not include information associated with a type for the third channel access procedure.

11. The method of claim 7 , wherein the type for the first channel access procedure or the second channel access procedure includes a first type or a second type,

wherein the first type is performed by sensing a channel during a plurality of slot durations within a contention window, and

wherein the second type is performed by sensing the channel for a predetermined duration.

12. The method of claim 11 , wherein the type for the first channel access procedure or the second channel access procedure further includes a third type, and

wherein the third type is performed by not sensing the channel.

13. A terminal in a wireless communication system, the terminal comprising:

a transceiver; and

a controller configured to:

receive, from a base station, via the transceiver, a random access response (RAR) including an uplink grant for a transmission of a message 3 (MSG3) associated with a random access procedure, the uplink grant including first information associated with a type for a first channel access procedure for the transmission of the MSG3,

perform, via the transceiver, the first channel access procedure based on the type identified by the first information,

transmit, to the base station, via the transceiver, the MSG3 associated with the random access procedure based on the first channel access procedure,

receive, from the base station, via the transceiver, downlink control information (DCI) scheduling a retransmission of the MSG3, the DCI including second information associated with a type for a second channel access procedure for the retransmission of the MSG3,

perform, via the transceiver, the second channel access procedure based on the type identified by the second information, and

transmit, to the base station, via the transceiver, the MSG3 based on the second channel access procedure.

14. The terminal of claim 13 , wherein the RAR further includes third information associated with a channel access priority class for the first channel access procedure, in case that the first information indicates a specific type for the first channel access procedure, and

wherein the first channel access procedure is performed based on the first information and the third information.

15. The terminal of claim 13 , wherein a cyclic redundancy check (CRC) for the DCI is scrambled by a temporary cell radio network temporary identifier (TC-RNTI) included in the RAR.

16. The terminal of claim 13 , wherein the controller is further configured to:

receive, from the base station, via the transceiver, DCI scheduling another retransmission of the MSG3,

perform, via the transceiver, a third channel access procedure based on the type identified by the first information, in case that the DCI scheduling the another retransmission does not include information associated with a type for the third channel access procedure, and

transmit, to the base station via the transceiver, the MSG3 based on the third channel access procedure.

17. The terminal of claim 13 , wherein the type for the first channel access procedure or the second channel access procedure includes a first type or a second type,

wherein the first type is performed by sensing a channel during a plurality of slot durations within a contention window, and

wherein the second type is performed by sensing the channel for a predetermined duration.

18. The terminal of claim 17 , wherein the type for the first channel access procedure or the second channel access procedure further includes a third type, and

wherein the third type is performed by not sensing the channel.

19. A base station in a wireless communication system, the base station comprising:

a transceiver; and

a controller configured to:

transmit, to a terminal, via the transceiver, a random access response (RAR) including an uplink grant for a transmission of a message 3 (MSG3) associated with a random access procedure, the uplink grant including first information associated with a type for a first channel access procedure for the transmission of the MSG3,

transmit, to the terminal, via the transceiver, downlink control information (DCI) scheduling a retransmission of the MSG3 in case that the transmission from the terminal of the MSG3 associated with the random access procedure based on the first channel access procedure is not received, the DCI including second information associated with a type for a second channel access procedure for the retransmission of the MSG3, and

receive, from the terminal, via the transceiver, the MSG3 based on the second channel access procedure, which is based on the type identified by the second information.

20. The base station of claim 19 , wherein the RAR further includes third information associated with a channel access priority class for the first channel access procedure, in case that the first information indicates a specific type for the first channel access procedure, and

wherein the first channel access procedure is based on the first information and the third information.

21. The base station of claim 19 , wherein a cyclic redundancy check (CRC) for the DCI is scrambled by a temporary cell radio network temporary identifier (TC-RNTI) included in the RAR.

22. The base station of claim 19 , wherein the controller is further configured to:

transmit, to the terminal, via the transceiver, DCI scheduling another retransmission of the MSG3 in case that the transmission of the MSG3is not received, and

receive, from the terminal via the transceiver, the MSG3 based on a third channel access procedure, which is based on the type identified by the first information, in case that the DCI scheduling the another retransmission does not include information associated with a type for the third channel access procedure.

23. The base station of claim 19 , wherein the type for the first channel access procedure or the second channel access procedure includes a first type or a second type,

wherein the first type is performed by sensing a channel during a plurality of slot durations within a contention window, and

wherein the second type is performed by sensing the channel for a predetermined duration.

24. The base station of claim 23 , wherein the type for the first channel access procedure or the second channel access procedure further includes a third type, and

wherein the third type is performed by not sensing the channel.