Method and device for controlling duplicate packet transmission in wireless communication system

1. A terminal for controlling packet duplication in a wireless communication system, the terminal comprising:

a transceiver; and

at least one processor coupled to the transceiver and configured to

receive, from a base station, Packet Data Convergence Protocol (PDCP) configuration information including a duplication field for a plurality of Radio Link Control (RLC) entities via a Radio resource control (RRC) message,

identify at least one activated RLC entity from among the plurality of RLC entities, based on the duplication field for the plurality of RLC entities, and

duplicate a PDCP packet and deliver the duplicated PDCP packet to the at least one activated RLC entity.

2. The terminal of claim 1 , wherein the at least one processor is further configured to:

transmit, to the base station, capability information indicating whether to support duplication transmission by using more than two RLC entities.

3. The terminal of claim 1 , wherein the duplication field for the plurality of RLC entities indicates ‘true’ for a first RLC entity and ‘false’ for a second RLC entity, and

wherein the at least one processor is further configured to:

activate the first RLC entity based on the duplication field for the plurality of RLC entities, and

deactivate the second RLC entity based on the duplication field for the plurality of RLC entities.

4. The terminal of claim 1 , wherein the duplication field for the plurality of RLC entities includes an index determined based on a logical channel identifier (ID) of the plurality of RLC entities.

5. The terminal of claim 1 , wherein the at least one processor is further configured to:

receive a duplication RLC activation or deactivation Medium Access Control (MAC) Control Element (CE), and

determine whether each of a plurality of secondary RLC entities is activated or deactivated based on the duplication RLC activation or deactivation MAC CE.

6. The terminal of claim 5 , wherein the duplication RLC activation or deactivation MAC CE comprises a Data Radio Bearer (DRB) index indicating an identity of a DRB and at least one RLC field that corresponds to each of the plurality of secondary RLC entities and indicates activation or deactivation status of duplication for a corresponding secondary RLC entity from among the plurality of secondary RLC entities.

7. The terminal of claim 6 , wherein the at least one RLC field indicating activation or deactivation of duplication for the corresponding RLC entity is identified by ascending order of logical channel IDs in an order of master cell group (MCG) and secondary cell group (SCG).

8. The terminal of claim 6 , wherein the at least one RLC field indicating activation or deactivation of duplication for the corresponding RLC entity comprises a first RLC field for a first RLC entity, and

wherein the at least one processor is further configured to:

when the first RLC field is set to 1, activate the first RLC entity for PDCP duplication, and

when the first RLC field is set to 0, deactivate the first RLC entity for PDCP duplication.

9. The terminal of claim 1 , wherein a primary RLC entity cannot be deactivated, and

wherein a plurality of secondary RLC entities transmit data when the plurality of secondary RLC entities are activated.

10. The terminal of claim 1 , wherein the at least one processor is further configured to:

indicate, by a PDCP entity, a deactivated RLC entity to discard all duplicated PDCP packets.

11. The terminal of claim 1 , wherein the at least one processor is further configured to:

receive, from the base station, logical channel configuration information including information associated with at least one cell used by a logical channel, and

determine not to apply the information associated with the at least one cell used by the logical channel when none or only one of the plurality of RLC entities remains activated.

12. The terminal of claim 1 , wherein the at least one processor is further configured to:

receive, from the base station, logical channel configuration information including information associated with cell restriction mapped with a logical channel;

wherein the cell restriction is not applied when none or only one of the plurality of RLC entities remains activated in a cell group regardless of the information associated with cell restriction mapped with the logical channel.

13. A method, performed by a terminal, for controlling packet duplication in a wireless communication system, the method comprising:

receiving, from a base station, Packet Data Convergence Protocol (PDCP) configuration information including a duplication field for a plurality of Radio Link Control (RLC) entities via a Radio resource control (RRC) message;

identifying at least one activated RLC entity from among the plurality of RLC entities based on the duplication field for the plurality of RLC entities; and

duplicating a PDCP packet and delivering the duplicated PDCP packet to the at least one activated RLC entity.

14. The method of claim 13 , wherein the duplication field for the plurality of RLC entities indicates ‘true’ for a first RLC entity and ‘false’ for a second RLC entity, and

wherein the method further comprises:

activating the first RLC entity based on the duplication field for the plurality of RLC entities; and

deactivating the second RLC entity based on the duplication field for the plurality of RLC entities.

15. The method of claim 13 , further comprising:

receiving, from the base station, a duplication RLC activation or deactivation Medium Access Control (MAC) Control Element (CE); and

determining whether each of a plurality of secondary RLC entities is activated or deactivated based on the duplication RLC activation or deactivation MAC CE.

16. The method of claim 15 , wherein the duplication RLC activation or deactivation MAC CE comprises a Data Radio Bearer (DRB) index indicating an identity of a DRB and at least one RLC field that corresponds to each of the plurality of secondary RLC entities and indicates activation or deactivation status of duplication for a corresponding secondary RLC entity from among the plurality of secondary RLC entities,

wherein a first RLC entity is activated for PDCP duplication when a first RLC field corresponding to the first RLC entity is set to 1, and

wherein a second RLC entity is deactivated for PDCP duplication when a second RLC field corresponding to the second RLC entity is set to 0.

17. The method of claim 16 , wherein the at least one RLC field indicating activation or deactivation of duplication for the corresponding RLC entity is identified by ascending order of logical channel IDs in an order of master cell group (MCG) and secondary cell group (SCG).

18. The method of claim 13 , wherein a primary RLC entity cannot be deactivated, and

wherein a plurality of secondary RLC entities transmit data when the plurality of secondary RLC entities are activated.

19. The method of claim 14 , further comprising:

receiving, from the base station, logical channel configuration information including information associated with at least one cell used by a logical channel; and

determining not to apply the information associated with the at least one cell used by the logical channel when none or only one of the plurality of RLC entities remains activated.

20. The method of claim 13 , further comprising receiving, from the base station, logical channel configuration information including information associated with cell restriction mapped with a logical channel;

wherein the cell restriction is not applied when none or only one of the plurality of RLC entities remains activated in a cell group regardless of the information associated with cell restriction mapped with the logical channel.