Method and apparatus for transmitting data using random access procedure in communication system

1. An operation method of a terminal in a communication system, the operation method comprising:

transmitting a first message A (MsgA) including a random access (RA) preamble #i and a payload to a base station;

receiving, from the base station, a message B (MsgB) including information indicating an RA preamble #k; and

transmitting a second MsgA including the RA preamble #k and data to the base station in a preamble reservation period,

wherein each of i and k is a natural number, and

wherein when i is equal to k, the data is transmitted on a physical uplink shared channel (PUSCH) occasion associated with the RA preamble #i selected by the terminal.

2. The operation method according to claim 1 , wherein the RA preamble #i and the RA preamble #k belong to a group A1 among the group A1 and a group A2, RA preambles belonging to the group A1 are used for transmission of delay-sensitive data, and RA preambles belonging to the group A2 are used for transmission of delay-tolerant data.

3. The operation method according to claim 2 , wherein one of configuration information of the group A1 and configuration information of the group A2 is included in random access channel (RACH) configuration information received from the base station, the configuration information of the group A1 indicates one or more of a number and indices of the RA preambles belonging to the group A1, and the configuration information of the group A2 indicates one or more of a number and indices of the RA preambles belonging to the group A2.

4. The operation method according to claim 2 , wherein the number of RA preambles belonging to the group A1 is determined based on a ratio of reserved RA preambles.

5. The operation method according to claim 1 , wherein the MsgB further includes information indicating that the preamble reservation period is activated.

6. The operation method according to claim 1 , wherein when the preamble reservation period ends, the reservation of the RA preamble #k is released.

7. The operation method according to claim 1 , wherein the second MsgA is transmitted by the terminal operating in a radio resource control (RRC) idle state or RRC inactive state.

8. An operation method of a terminal in a communication system, the operation method comprising:

receiving random access channel (RACH) configuration information from a base station;

transmitting a first message A (MsgA) including a random access (RA) preamble #i selected based on the RACH configuration information and a payload to the base station;

transmitting a second MsgA including an RA preamble #k selected based on the RACH configuration information and a payload to the base station;

stopping repeated transmission operations of the MsgA when a message B (MsgB) including information indicating that an RA preamble #j is reserved is received within a response window; and

transmitting a third MsgA including the RA preamble #j and a payload to the base station for a preamble reservation period associated with the RA preamble #j,

wherein each of i, k, and j is a natural number, and

wherein the MsgB further includes information indicating that the preamble reservation period is activated.

9. The operation method according to claim 8 , wherein the RACH configuration information includes configuration information of a group A1 to which the RA preamble #i, the RA preamble #k, and the RA preamble #j belong, the configuration information of the group A1 indicates one or more of a number and indices of RA preambles belonging to the group A1, and the RA preambles belonging to the group A1 are used for transmission of delay-sensitive data.

10. The operation method according to claim 9 , wherein the number of the RA preambles belonging to the group A1 is determined based on a ratio of reserved RA preambles.

11. The operation method according to claim 8 , wherein when i is equal to j, the payload of the third MsgA is transmitted on a physical uplink shared channel (PUSCH) occasion associated with the RA preamble #i selected by the terminal, and when k is equal to j, the payload of the third MsgA is transmitted on a PUSCH occasion associated with the RA preamble #k selected by the terminal.

12. The operation method according to claim 8 , wherein when i, k, and j are different from each other, the payload of the third MsgA is transmitted on a PUSCH occasion associated with the RA preamble #j selected by the base station.

13. The operation method according to claim 8 , wherein when the preamble reservation period ends, the reservation of the RA preamble #j is released.

14. An operation method of a base station in a communication system, the operation method comprising:

transmitting radio access channel (RACH) configuration information to a terminal, wherein the RACH configuration information includes configuration information of a group A1, which indicates one or more of a number and indices of RA preambles belonging to the group A1;

receiving a first message A (MsgA) including a random access (RA) preamble #i and a payload from the terminal, wherein the RA preamble #i belongs to a group A1 consisting of RA preambles used for data transmission;

transmitting a message B (MsgB) including information indicating the RA preamble #i to the terminal; and

receiving a second MsgA including the RA preamble #i and data from the terminal in a preamble reservation period,

wherein i is a natural number.

15. The operation method according to claim 14 , wherein the number of the RA preambles belonging to the group A1 is determined based on a ratio of reserved RA preambles.

16. The operation method according to claim 14 , wherein the MsgB further includes information indicating that the preamble reservation period is activated, and when the preamble reservation period ends, the reservation of the RA preamble #i is released.

17. The operation method according to claim 14 , wherein the second MsgA is received from the terminal operating in a radio resource control (RRC) idle state or RRC inactive state.