Method and apparatus for controlling packet duplicate transmission in a wireless communication system

Abstract

To provide a terminal and a method for controlling a packet duplicate transmission.SOLUTION: A terminal for performing a packet duplicate transmission receives duplication RLC activation / non-activation MAC CE related to a plurality of secondary RLC entities of one DRB. The duplication RLC activation / non-activation MAC CE contains a DRB index and a plurality of RLC fields indicating an identifier of the DRB. The plurality of RLC fields contains a RLC field. The RLC field instructs an activation state or a non-activation state of a PDCP duplication related to the secondary RLC entity corresponded to the RLC field in the plurality of secondary RLC entities. In the case where the duplication RLC activation / non-activation MAC CE indicates the activation of the PDCP duplication related to at least one secondary RLC entity, the PDCP packet is duplicated, and the duplicated PDCP packet is transmitted to at least the one secondary RLC entity.SELECTED DRAWING: Figure 12

Description

[Technical field]

[0001] The present invention relates to a method and apparatus for controlling packet duplicate transmission in a wireless communication system. [Background technology]

[0002] Since the commercialization of 4G communication systems, efforts have been made to develop improved 5G or pre-5G communication systems to meet the increasing demand for wireless data traffic. For this reason, 5G communication systems or pre-5G communication systems are also called beyond 4G network communication systems or post-LTE (long term evolution) systems.

[0003] 3GPP(3 rd The 5G communication system defined by the 5G-Generation Partnership Project is called the NR (new radio) system. In order to achieve high data transmission rates, 5G communication systems are being considered for implementation in ultra-high frequency (mmWave) bands (e.g., 60 GHz bands). In order to mitigate radio wave path loss in the ultra-high frequency band and extend the radio wave transmission distance, the following technologies have been discussed in the 5G communication system: beamforming, massive MIMO (multiple-input multiple-output), full dimensional multiple-input multiple-output (FD-MIMO), array antenna, analog beamforming, and large scale antenna, and have been applied to the NR system.

[0004] In addition, to improve the system network, technologies such as advanced small cells, cloud radio access networks (cloud RAN), ultra-dense networks, device to device communication (D2D), wireless backhaul, moving networks, cooperative communication, coordinated multi-points (CoMP), and receive interference cancellation are being developed in the 5G communication system.

[0005] In addition, advanced coding modulation (ACM) schemes such as hybrid FSK and QAM modulation (FQAM) and sliding window superposition coding (SWSC), as well as advanced access technologies such as filter bank multi carrier (FBMC), non-orthogonal multiple access (NOMA), and sparse code multiple access (SCMA) have been developed for the 5G system.

[0006] Meanwhile, the Internet is evolving from a human-centered connected network in which humans generate and consume information to an Internet of Things (IoT) network in which information is exchanged and processed between distributed components such as things. IoE (Internet of Everything) technology is also emerging, combining big data processing technology via connections to cloud servers and other devices with IoT technology. To realize IoT, technological elements such as sensing technology, wired and wireless communication and network infrastructure, service interface technology, and security technology are required, and recently, technologies such as sensor networks for connecting things, machine to machine (M2M), and machine type communication (MTC) are being researched.

[0007] In an IoT environment, intelligent IT (internet technology) services can be provided that collect and analyze data generated by connected things and create new value in human life. Through the fusion and integration of existing IT (information technology) with various industries, IoT will also be applied to fields such as smart homes, smart buildings, smart cities, smart cars or connected cars, smart grids, healthcare, smart home appliances, and advanced medical services. As a result, various attempts are being made to apply 5G communication systems to IoT networks.

[0008] For example, 5G communications such as sensor networks, machine to machine (M2M) communications, and MTC are realized through techniques such as beamforming, MIMO, and array antennas. The application of cloud radio access network (cloud RAN) as the big data processing technology mentioned above can also be considered an example of the fusion of 5G technology and IoT technology. As a result of the above and the development of mobile communication systems, various services can be provided, and there is a demand for methods for providing such services effectively. Summary of the Invention [Means for solving the problem]

[0009] According to an embodiment of the present disclosure, a terminal for performing packet duplicate transmission in a wireless communication systemIn The terminal includes a transceiver unit and Connected to the transceiver at least one processor, the at least one processor comprising: From the base station Replication involving multiple secondary RLC (Radio Link Control) entities of one Data Radio Bearer (DRB) Instructs the activation or deactivation of A MAC (Medium Access Control) CE (Control Element) receives the duplicate. Instructs the activation or deactivation of MAC CE is DRBID and multiple RLC fields M, front The plurality of RLC fields includes an RLC field, the RLC field being a PDCP associated with a secondary RLC entity corresponding to the RLC field among the plurality of secondary RLC entities. (Packet Data Convergence Protocol) Indicating the activation or deactivation state of a copy, Instructs the activation or deactivation of MAC CE Among the plurality of secondary RLC entities, if it indicates activation of PDCP duplication related to at least one secondary RLC entity, duplication of PDCP packets; PDCP packets to the primary RLC entity and The at least one secondary RLC entity is then transmitted to the at least one secondary RLC entity.

[0010] According to an embodiment of the present disclosure, a terminal in a wireless communication system twist Method for performing packet duplication transmission - Patents.com In , the method comprising: From the base station Replication involving multiple secondary RLC (Radio Link Control) entities of one Data Radio Bearer (DRB) Instructs the activation or deactivation of receiving a Medium Access Control (MAC) Control Element (CE); Instructs the activation or deactivation of MAC CE is DRB IDand a plurality of RLC fields, the plurality of RLC fields including an RLC field indicating an activation state or a deactivation state of a PDCP replica associated with a secondary RLC entity corresponding to the RLC field among the plurality of secondary RLC entities, the replica Instructs the activation or deactivation of MAC CE Among the plurality of secondary RLC entities , a PDCP associated with at least one secondary RLC entity (Packet Data Convergence Protocol) When activating duplication, the PDCP packet is duplicated and the previous Record P DCP packets Primary RLC entity and and transmitting the at least one secondary RLC entity to the at least one secondary RLC entity. Effect of the Invention

[0011] According to the disclosed embodiment, an apparatus and a method for effectively providing services in a mobile communication system are provided. [Brief description of the drawings]

[0012] [Figure 1] 2 is a block diagram illustrating a schematic structure of a radio bearer configured with packet duplicate transmission according to an embodiment of the present invention; [Diagram 2] 11 is a diagram for explaining an operation of packet duplicate transmission according to an embodiment of the present invention; FIG. [Diagram 3] 11 is a diagram illustrating an operation of packet duplicate transmission according to another embodiment of the present invention. [Figure 4] 10 is a flowchart illustrating an operation of performing packet duplicate transmission through uplink duplicate setup according to an embodiment of the present invention. [Diagram 5] 1 is a diagram illustrating a method for a base station to control activation and deactivation of packet duplication according to an embodiment of the present invention. [Figure 6] FIG. 13 illustrates a packet duplication activation / deactivation message format according to one embodiment of the present invention. [Figure 7] FIG. 13 illustrates a packet duplication activation / deactivation message format according to another embodiment of the present invention. [Figure 8] FIG. 13 illustrates a packet duplication activation / deactivation message format according to yet another embodiment of the present invention. [Figure 9] FIG. 13 illustrates a packet duplication activation / deactivation message format according to yet another embodiment of the present invention. [Figure 10] FIG. 13 illustrates a packet duplication activation / deactivation message format according to yet another embodiment of the present invention. [Figure 11] 11 is a diagram illustrating a method for a terminal to inform a base station whether or not it has a packet duplication activation function according to an embodiment of the present invention. [Figure 12] 4 is a flowchart illustrating an operation of performing packet duplicate transmission according to an embodiment of the present invention. [Figure 13] 2 is a block diagram illustrating a schematic internal structure of a terminal according to an embodiment of the present invention; [Figure 14] 1 is a block diagram illustrating a schematic configuration of a base station according to an embodiment of the present invention. [Figure 15] FIG. 13 is a block diagram illustrating a schematic structure of a radio bearer configured with packet duplicate transmission according to another embodiment of the present invention; [Figure 16] 13 is a diagram illustrating a method in which a base station controls activation and deactivation of packet duplication according to another embodiment of the present invention. [Figure 17] A diagram to explain a method in which a base station controls activation and deactivation in cell carrier aggregation according to one embodiment of the present invention. [Figure 18] 11 is a diagram illustrating a method of applying a cell configuration when packet duplicate transmission is deactivated according to an embodiment of the present invention. [Figure 19] 4 is a flow chart illustrating a method for applying cell limits for packet duplication according to one embodiment of the present invention. [Figure 20]11 is a diagram for explaining an operation due to cell deactivation in a bearer with packet duplication set according to an embodiment of the present invention. FIG. [Figure 21] 11 is a flowchart illustrating an operation of a transmitting PDCP device performing packet duplication according to an embodiment of the present invention. [Figure 22] 11 is a diagram illustrating an operation of a specific RLC device in response to deactivation of packet duplication transmission in a bearer in which packet duplication is configured according to an embodiment of the present invention. [Figure 23] 11 is a diagram for explaining an operation of applying cell restriction when two or more cell groups are applied according to an embodiment of the present invention. FIG. [Figure 24] 11 is a block diagram illustrating an internal structure of a terminal according to another embodiment of the present invention. [Diagram 25] FIG. 11 is a block diagram illustrating a configuration of a base station according to another embodiment of the present invention. [Figure 26] FIG. 13 illustrates a packet duplication activation / deactivation message format according to another embodiment of the present invention. [Figure 27] FIG. 13 illustrates a packet duplication activation / deactivation message format according to yet another embodiment of the present invention. [Figure 28] FIG. 13 illustrates a packet duplication activation / deactivation message format according to yet another embodiment of the present invention. [Figure 29] FIG. 2 illustrates a MAC subheader format for a variable length MAC CE according to one embodiment of the present invention. [Diagram 30] FIG. 2 illustrates a MAC subheader format for fixed length MAC CE according to one embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0013] According to an aspect of the present invention, a method for controlling packet duplication transmission in a terminal in a wireless communication system includes the steps of: receiving a packet duplication configuration related to a radio bearer from a base station through a radio resource control (RRC) message; checking, for a plurality of radio link control (RLC) devices, whether each RLC device is configured to be used for uplink packet duplication transmission; and, if packet duplication transmission is activated, performing packet duplication transmission using the RLC device configured to be used for uplink packet duplication transmission.

[0014] According to one aspect of the present invention, the step of checking, for the plurality of RLC devices, whether each RLC device is configured to be used for uplink packet duplicate transmission preferably includes a step of receiving, from the base station, information instructing the plurality of RLC devices to activate or deactivate packet duplication via a MAC CE (medium access control element), and a step of checking, based on the information instructing the activation or deactivation of packet duplication, whether each RLC device is configured to be used for uplink packet duplicate transmission. According to one embodiment of the present disclosure, the information indicating the activation or deactivation of packet duplication preferably includes radio bearer identification information including at least one of a radio bearer index or a radio bearer ID, and a plurality of fields corresponding to each RLC device. According to one embodiment of the present disclosure, it is preferable that the plurality of fields corresponding to each RLC device are at least one of a plurality of fields corresponding to each of all RLC devices configured for the radio bearer and a plurality of fields corresponding to each of the RLC devices configured to be used for uplink packet duplication transmission in a packet duplication configuration associated with the radio bearer. According to one embodiment of the present disclosure, the RRC message preferably includes information related to an RLC device to be used for uplink packet duplicate transmission for the plurality of RLC devices, and the step of checking, for the plurality of RLC devices, whether each RLC device is configured to be used for uplink link packet duplicate transmission preferably includes a step of checking, based on the information related to an RLC device to be used for uplink link packet duplicate transmission, whether each RLC device is configured to be used for uplink link packet duplicate transmission.

[0015] According to an embodiment of the present disclosure, the step of performing packet duplicate transmission using an RLC device configured to be used for uplink packet duplicate transmission when the packet duplicate transmission is activated preferably includes the steps of receiving, from the base station, via a MAC CE, information instructing the RLC device configured to be used for the uplink packet duplicate transmission to activate or deactivate packet duplication, and activating the packet duplicate transmission when the information instructing the activation of packet duplication is received. According to one embodiment of the present disclosure, it is preferable that the information related to the RLC device used for the uplink packet duplicate transmission includes at least one of a list of RLC devices used for the uplink packet duplicate transmission, an ID of the RLC device, a logical channel ID, and a combination of a logical channel ID and a cell group ID. According to an embodiment of the present disclosure, the step of performing packet duplicate transmission using an RLC device configured to be used for uplink packet duplicate transmission when the packet duplicate transmission is activated preferably includes the steps of receiving, from the base station via a MAC CE, information instructing activation or deactivation of packet duplicate transmission for the radio bearer, and activating the packet duplicate transmission when the information instructing activation of the packet duplicate transmission is received.

[0016] According to one embodiment of the present disclosure, a terminal for controlling packet duplicate transmission in a wireless communication system includes a transceiver unit, a memory, and at least one processor, and is configured to receive packet duplicate configuration related to a radio bearer from a base station via an RRC (radio resource control) message, check whether each RLC (radio link control) device is configured to be used for uplink packet duplicate transmission, and perform packet duplicate transmission using the RLC device configured to be used for uplink packet duplicate transmission when packet duplicate transmission is activated.

[0017] According to one embodiment of the present disclosure, it is preferable that the at least one processor receives, from the base station via a medium access control (MAC) control element (CE), information instructing a plurality of RLC devices to activate or deactivate packet duplication, and checks whether each of the RLC devices is configured to be used for uplink packet duplication transmission based on the information instructing the activation or deactivation of packet duplication. According to one embodiment of the present disclosure, the information indicating the activation or deactivation of packet duplication preferably includes radio bearer identification information including at least one of a radio bearer index or a radio bearer ID, and a plurality of fields corresponding to each RLC device. According to one embodiment of the present disclosure, it is preferable that the plurality of fields corresponding to each RLC device are at least one of a plurality of fields corresponding to each of all RLC devices configured for the radio bearer and a plurality of fields corresponding to each of the RLC devices configured to be used for uplink packet duplication transmission in a packet duplication configuration associated with the radio bearer. According to one embodiment of the present disclosure, it is preferable that the RRC message includes information related to an RLC device to be used for uplink packet duplicate transmission for the multiple RLC devices, and the at least one processor checks whether each of the RLC devices is configured to be used for uplink packet duplicate transmission based on the information related to the RLC device to be used for uplink packet duplicate transmission. According to one embodiment of the present disclosure, the at least one processor preferably receives, from the base station via a MAC CE, information instructing an RLC device configured to be used for the uplink packet duplication transmission to activate or deactivate packet duplication, and activates the packet duplication transmission when the processor receives information instructing the activation of the packet duplication. According to one embodiment of the present disclosure, it is preferable that the information related to the RLC device used for the uplink packet duplicate transmission includes at least one of a list of RLC devices used for the uplink packet duplicate transmission, an ID of the RLC device, a logical channel ID, and a combination of a logical channel ID and a cell group ID.

[0018] Hereinafter, embodiments of the present disclosure will be described in detail with reference to the accompanying drawings. In the description of the present embodiment, description contents that are well known in the technical field to which the present disclosure belongs and are not directly related to the present disclosure will be omitted. This is to avoid making the gist of the present disclosure unclear and to more clearly convey it by omitting unnecessary explanations. For the same reason, in the accompanying drawings, some components are exaggerated, omitted, or illustrated in a schematic manner, and the size of each component does not entirely reflect the actual size. In each drawing, the same reference numerals are used to refer to the same or corresponding components.

[0019] The advantages, features and methods of achieving the same of the present disclosure will become more apparent with reference to the following detailed embodiments taken in conjunction with the accompanying drawings. However, the present disclosure is not limited to the embodiments disclosed below, but may be embodied in various different forms, and the present disclosure is provided so that the disclosure will be complete and will fully convey the scope of the invention to those skilled in the art to which the disclosure pertains, and the present disclosure is defined only by the scope of the claims. Like reference numbers refer to like elements throughout the specification.

[0020] At this time, it will be understood that each block of the process flowchart and combinations of the flowcharts can be implemented by computer program instructions. The computer program instructions may also be loaded into a processor of a general purpose computer, special purpose computer, or other programmable data processing device, such that the instructions, when executed by the processor of the computer or other programmable data processing device, create means for performing the functions described in the flowchart blocks. The computer program instructions may be stored in a computer-usable or computer-readable memory that can direct a computer, or other programmable data processing device, to implement functions in a particular manner, such that the instructions stored in the computer-usable or computer-readable memory may produce an article of manufacture that includes instruction means that perform the functions described in the flowchart blocks.

[0021] The computer program instructions may be embodied on a computer, or other programmable data processing device, such that a series of operational steps are performed on the computer, or other programmable data processing device, to generate a computer-implemented process, and the instructions that cause the computer, or other programmable data processing device, to provide steps for performing the functions described in the flowchart blocks. Furthermore, each block may represent a module, a segment, or a portion of code that includes one or more executable instructions for executing a specified logical function. It should also be noted that in some alternative implementations, the functions noted in the blocks may occur out of order. For example, two blocks shown in succession may in fact be executed substantially concurrently, or the blocks may sometimes be executed in the reverse order depending on the functionality involved.

[0022] In this regard, the term "unit" as used in this embodiment means software or a hardware component such as an FPGA (field-programmable gate array) or an ASIC (application-specific integrated circuit), and the "unit" performs a certain role. However, the term "part" is not intended to be limited to software or hardware. A "unit" is configured to reside on an addressable recording medium and to execute one or more processors. Thus, by way of example, a "part" includes components such as software components, object-oriented software components, class components and task components, as well as processes, functions, attributes, procedures, subroutines, segments of program code, drivers, firmware, microcode, circuits, data, databases, data structures, tables, arrays, and variables. The functionality provided within the components and units may be further combined into fewer components and units or further separated into additional components and units. Moreover, the components and "parts" may also be embodied to implement one or more central processing units (CPUs) within the device or within a secure multimedia card. Furthermore, in this embodiment, the "unit" may include one or more processors.

[0023] In the following description, terms for identifying connection nodes, terms for designating network entities, terms for designating messages, terms for designating interfaces between entity networks, terms for designating various identification information, etc. are provided as examples for the convenience of description. Therefore, the present disclosure is not limited to the terms described below, but other terms referring to objects having equivalent technical meanings may also be used.

[0024] For ease of explanation, the present disclosure will use terms and names defined in the 3GPP LTE (3rd Generation Partnership Project Long Term Evolution) standard, or terms and names modified based on them. However, the present disclosure is not limited by the above terms and names, and may be equally applied to systems according to other standards. In this disclosure, for ease of explanation, “eNB” may be used interchangeably with “gNB”. That is, a base station described as an "eNB" can refer to a "gNB." In this disclosure, the term terminal can refer to a variety of wireless communication devices, not just mobile phones, NB-IoT devices, and sensors.

[0025] FIG. 1 is a block diagram that illustrates a schematic diagram of a radio bearer structure with packet duplication transmission according to an embodiment of the present invention. Packet duplicate transmission means duplicating a packet at the sender and transmitting the packet over different paths.

[0026] Referring to FIG. 1, a radio bearer structure according to an embodiment of the present invention shows a single packet data convergence protocol (PDCP) device (1a-10) connected to four RLC devices, RLC1 (1a-20), RLC2 (1a-30), RLC3 (1a-40), and RLC4 (1a-50), in order to support several paths. However, this is only an example, and any number of RLC devices may be connected to the PDCP device, and the base station can set up a radio bearer structure according to the radio link and network structure.

[0027] In a radio bearer structure according to one embodiment of the present invention, the layer that performs packet duplication is the PDCP layer (1a-10), and after packet duplication is performed in the PDCP layer (1a-10), the duplicated packets are transmitted to two or more different RLC devices so that the packets are transmitted independently. Since one radio bearer has one PDCP device regardless of packet duplication, the PDCP device corresponds to one radio bearer ID. In one embodiment, the radio bearer including the PDCP1 (1a-10) is both a data radio bearer (DRB) and a signaling radio bearer (SRB).

[0028] The RLC devices are divided into a primary RLC device (1a-20) and secondary RLC devices (1a-30, 1a-40, 1a-50) according to their applications. The primary RLC device (1a-20) is a device that constantly transmits packets regardless of whether packet duplication is enabled. The secondary RLC devices (1a-30, 1a-40, 1a-50) are devices that perform packet transmission only when packet duplication is activated. In addition, the secondary RLC devices (1a-30, 1a-40, 1a-50) do not participate in uplink packet transmission according to the configuration method. If a split bearer is applied, when the data that the transmitter needs to send is below (or below) a certain threshold, it transmits the packet only to the primary RLC, and when it exceeds (or exceeds) the threshold, it transmits the packet to both the primary device and the secondary device. The detailed operation configuration may be included in at least one of a radio bearer configuration, an RLC bearer configuration, a PDCP configuration, and an RLC configuration of an RRC configuration message and transmitted to the terminal.

[0029] FIG. 2 is a diagram for explaining the operation of packet duplicate transmission according to an embodiment of the present invention. In the following, it is assumed that the radio bearer structure in which packet duplication is configured is the radio bearer structure shown in FIG. Referring to FIG. 2, in one embodiment, when packet duplicate transmission is configured and activated, the transmitting PDCP device (1b-10) duplicates the packet (1b-60) and transmits each duplicated packet (1b-70, 1b-80, 1b-90, 1b-100) to all configured RLC devices (1b-20, 1b-30, 1b-40, 1b-50).

[0030] At this time, each RLC device can operate in an independent mode. If each RLC device operates in RLC acknowledged mode (AM), each RLC device can also independently perform automatic repeat request (ARQ) operations. As shown in FIG. 2, if four RLC devices (1b-20, 1b-30, 1b-40, 1b-50) are configured on a radio bearer, the transmitting PDCP device (1b-10) can generate a total of four identical duplicate packets for one packet and transmit the packet to the four RLC devices (1b-20, 1b-30, 1b-40, 1b-50).

[0031] FIG. 3 is a diagram for explaining an operation of packet duplicate transmission according to another embodiment of the present invention. After packet duplication, sending the same duplicated packet to multiple routes results in inefficient use of radio resources because of the duplicated use of radio resources. It is therefore necessary to adjust the number of packets that are replicated during operation of a wireless network in order to reduce such inefficiencies. In addition, downlink packet duplication completely controlled by the base station and uplink packet duplication controlled by the terminal according to the setting of the base station may use different numbers of RLC devices to perform packet duplication transmission.

[0032] Referring to FIG. 3, only some of the configured RLC devices can perform packet duplication. In one embodiment, the transmitting PDCP device (1c-10) duplicates the packet (1c-100), but does not use any of the four configured RLC devices (1c-20, 1c-30, 1c-40, 1c-50), and only uses a total of three RLC devices, RLC1 (1c-20), RLC2 (1c-30), and RLC3 (1c-40), for packet duplication. Therefore, RLC4(1c-50) does not participate in packet duplicate transmission. Whether each RLC participates in packet duplication transmission can be configured by the base station. In the RLC settings for each RLC device, an RLC device with the "ul-duplication" field set to "true" participates in packet duplication transmission, and an RLC device with the "ul-duplication" field set to "false" indicates that it does not participate in packet duplication transmission.

[0033] Whether each RLC device participates in packet duplicate transmission can also be set by other methods. For example, a list of RLC devices to be used for packet duplication may be specified and conveyed within the PDCP configuration or within the radio bearer configuration. At this time, the logical channel ID can be clearly indicated and the relevant RLC device can be specified. In addition, in a dual connectivity structure or a multiple connectivity structure, a corresponding RLC can be specified by a combination of a logical channel ID and a cell group ID. Additionally, the identity of the RLC device (RLC bearer) can be specified. As indicated by the corresponding 'ul_duplication' field, whether or not to participate in packet duplication transmission can also be changed by a packet duplication activation / deactivation message, which will be described later with reference to FIGS. In another embodiment, it can be set whether or not the RLC device having the 'ul_duplication' field set to 'true' is actually activated and used for packet duplication transmission.

[0034] FIG. 4 is a flowchart illustrating an operation of performing packet duplicate transmission through uplink duplicate setup according to an embodiment of the present invention. In step (1d-10), packet duplication for the radio bearer is set. Then, in step (1d-20), the terminal checks whether each RLC device is configured to be used for uplink packet duplicate transmission.

[0035] In one embodiment, each RLC device corresponds to a logical channel and therefore checks whether each logical channel is configured to be used for uplink packet duplication. In this case, the RLC device or logical channel is set to be used for uplink packet duplication by checking whether the 'ul-duplication' field is set to 'true' as described in FIG. 3, or via a list of RLC devices to be used for packet duplication.

[0036] If an RLC device or logical channel is configured to be used for uplink packet duplication, in step (1d-30), in the case of an RLC device configured to be used for uplink packet duplication, when packet duplication is activated, the corresponding RLC device is used for uplink packet duplication. If an RLC device or logical channel is not configured to be used for uplink packet duplication, in step (1d-40), the RLC device that is not configured to be used for uplink packet duplication does not use the corresponding RLC device for uplink packet duplication when packet duplication is activated. In other words, when packet duplication is activated, the transmitting PDCP device transmits the duplicated packet to the RLC device used for packet duplication activation, thereby performing packet duplication transmission.

[0037] FIG. 5 is a diagram illustrating a method for a base station to control activation and deactivation of packet duplication according to an embodiment of the present invention. Packet duplicate transmission increases radio resource consumption because the same packet is transmitted using two or more RLC units. It is undesirable to perform packet duplication all the time since it would result in inefficiencies in radio resource utilization. Therefore, packet duplicate transmission is performed only when it is necessary. In a radio bearer for which packet duplication is configured, the act of actually performing packet duplication is called activating packet duplication. Conversely, in a radio bearer for which packet duplication is set, not performing packet duplication is called deactivation of packet duplication.

[0038] In step (1e-10), the base station transmits a packet duplication activation / deactivation message to the terminal. In this case, the same type of message may be used for activation and deactivation, and activation and deactivation of packet duplication may be distinguished by a value included in the message. The packet duplication activation / deactivation message indicates which radio bearer associated packet duplication is to be activated or deactivated. After the terminal receives such a message, in step (1e-20), it applies packet duplication activation or deactivation according to the instruction contained in the message.

[0039] The activation message format and the deactivation message format of packet duplication will be described in more detail with reference to FIGS. FIG. 6 is a diagram illustrating packet duplication activation / deactivation message formats according to one embodiment of the present invention. Referring to FIG. 6, the packet duplication activation / deactivation message is in a MAC CE format consisting of one byte, in other words, eight bitmaps.

[0040] Each bitmap bit indicates the activation or deactivation state of packet duplication transmission associated with a particular radio bearer, with "1" indicating activation and "0" indicating deactivation. Additionally, the eight bitmaps indicate packet duplication activation and duplication deactivation states associated with up to eight radio bearers. D 0 (1f-10) to D 7 The bearer that each bit (1f-80) indicates is also determined according to a pre-configured method. In one embodiment, each bit is applied in ascending order of the DRB ID of the radio bearer with packet duplication set in the MAC device where the MAC CE is transmitted and where there is an RLC device. Also, each bit is applied in ascending order of the DRB ID of the radio bearer with packet duplication set, using the security key corresponding to the cell group to which the MAC device where the MAC CE is transmitted belongs.

[0041] FIG. 7 is a diagram showing an activation / deactivation message format for packet duplication according to another embodiment of the present invention. Referring to FIG. 7, the activation / deactivation message for packet duplication is in the MAC CE format. In one embodiment, the activation / deactivation message for packet duplication includes a DRB index (1g-10) and an L i (i = 1, 2, 3, 4, 5) field (1g-20, 1g-30, 1g-40, 1g-50, 1g-60). At this time, the DRB index is a pre-set value, and one of the following values is applied.

[0042] <The base station explicitly indicates in the DRB setting at the time of setting> <Applied in ascending order of the DRB ID of the radio bearer with packet duplication set> <Applied in ascending order of the DRB ID of the radio bearer with packet duplication set in the MAC device where there is an RLC device and where the MAC CE is transmitted> <Use the DRB ID value as it is> Here, the L i field can set whether to use the corresponding RLC device for packet duplicate transmission by the bit value of the L i field to indicate each RLC device. For example, if the value of the L i field is "1", the corresponding RLC device is used for packet duplicate transmission, and if it is "0", the corresponding RLC device is not used for packet duplicate transmission. Which L iWhich RLC device to be instructed is a pre-set value, and one of the following values is applied.

[0043] <Apply in ascending (descending) order of the LCID (logical channel ID) of the master cell group, and then apply in ascending (descending) order of the LCID of the secondary cell group> <Pre-set the index corresponding to the RLC device and in ascending order of the index> <Apply in ascending order of the priority of the corresponding logical channel. When the priorities are the same, arrange them in ascending order of the master cell group and LCID> By receiving the activation / deactivation message of packet duplication, the terminal can determine which RLC device of which DRB to use for packet duplication transmission and perform packet duplication transmission.

[0044] Here, L i The RLC device with the field is also all the RLC devices set for the DRB. In this case, for the radio bearer in FIG. 3, all four RLC devices set can i Have the field, and whether to use the RLC device for packet duplication transmission can be set respectively. In other embodiments, only the RLC device in which the "ul_duplication" field described in FIG. 3 is set to "true" can i Also have the corresponding L In that case, for the radio bearer in FIG. 3, only three RLC devices in which "ul_duplication" is set to "true" can i Have the field, and only for this RLC device can it be set whether to use it for packet duplication transmission.

[0045] FIG. 8 is a diagram showing the activation / deactivation message format of packet duplication according to still another embodiment of the present invention. Referring to FIG. 8, the activation / deactivation message of packet duplication is in the MAC CE format. In one embodiment, the packet duplication activation / deactivation message includes a DRB ID (1h-10) and an L corresponding to the RLC device i (i = 1, 2, 3, 4, 5, 6, 7, 8) fields (1h-30, 1h-40, 1h-50, 1h-60, 1h-70, 1h-80, 1h-90, 1h-100). Optionally, it may also include a reserved (R) bit (1h-20).

[0046] Here, L i The field can indicate each RLC device. Also, L i Based on the bit value of the L field, it is possible to set whether the corresponding RLC device is used for packet duplicate transmission. For example, if the value of the L i field is "1", the corresponding RLC device is used for packet duplicate transmission, and if it is "0", the corresponding RLC device is not used for packet duplicate transmission. Which L i indicates which RLC device is a pre-set value, and one of the following values is applied.

[0047] <Apply the LCID of the master cell group in ascending (descending) order, and then apply the LCID of the secondary cell group in ascending (descending) order> <Pre-set the index corresponding to the RLC device and apply it in ascending order of the index> <Apply the priority of the corresponding logical channel in ascending order. When the priorities are the same, align them in ascending order of the master cell group and LCID> By receiving the packet duplication activation / deactivation message, the terminal can determine which RLC device of which DRB is used for packet duplicate transmission and perform packet duplicate transmission.

[0048] Here, L i The RLC device having the field is also all the RLC devices set for the DRB. In this case, for the radio bearer in Figure 3, all four configured RLC devices are L i Each of the fields can be set to indicate whether the RLC device is used for packet duplicate transmission. In another embodiment, only the RLC devices that have the "ul_duplication" field described in FIG. 3 set to "true" receive the corresponding L i It can also have fields. In this case, for the radio bearer in Figure 3, only the three RLC devices with "ul_duplication" set to "true" i A field can be included to set whether only this RLC device uses packet duplicate transmission.

[0049] FIG. 9 illustrates a packet duplication activation / deactivation message format according to yet another embodiment of the present invention. Referring to FIG. 9, the packet duplication activation / deactivation message is in MAC CE format. In one embodiment, the packet duplication activation / deactivation message includes the DRB ID (1i-10) and N indicating the number of RLC devices to be used for uplink packet duplication. dup It has fields (1i-20). The DRB ID field indicates the ID of the DRB to which the activation or deactivation of packet duplicate transmission applies.

[0050] After receiving the MAC CE, the terminal dup The RLC device is used for the number set in the field, and packet duplicate transmission is performed. Which RLC device among the RLC devices configured in the terminal is used to perform packet duplication transmission can be applied according to a pre-configured method, and can be applied in one of the following ways.

[0051] < Apply the LCID of the master cell group in ascending (descending) order, then apply the LCID of the secondary cell group in ascending (descending) order, and N dup Select RLC device > <Pre-set the index corresponding to the RLC device, and select N RLC devices in ascending order of the index.> dup <devices.> <Apply in ascending order of the priority of the corresponding logical channel. When the priorities are the same, select Ndup RLC devices in ascending order of the master cell group and LCID.> By receiving the packet duplication activation / deactivation message, the terminal can determine which RLC device of which DRB is used for packet duplication transmission and perform packet duplication transmission.

[0052] FIG. 10 is a diagram showing the packet duplication activation / deactivation message format according to still another embodiment of the present invention. Referring to FIG. 10, the packet duplication activation / deactivation message is in the MAC CE format. In FIGS. 7 to 9, the format of the packet duplication activation / deactivation message is described for instructing whether to activate packet duplication related to the radio bearer. However, by using such a message, packet duplication can also be set for several radio bearers.

[0053] In FIG. 10, three messages (1j-10, 1j-20, 1j-30) of the format having the DRB index described in FIG. 7 and the L field corresponding to the RLC device are superimposed to form one MAC CE. i <devices.> However, this is only an example, and any number of MAC CEs may be superimposed. The number of superimposed MAC CEs can be set to the pre-set number, the number of radio bearers for which packet duplication is set, or variably determined only for the radio bearers for which the base station wants to set packet duplication. If the length of the MAC CE format is variable, the L field (length field) of the MAC sub-header must be included. At this time, for the RLC device of the radio bearer indicated by the DRB index, packet duplication can be allowed. Also, the DRB index is a pre-set value, and one of the following values is applied.

[0054] <When setting up the base station, explicitly indicate in the DRB setting> <Apply in ascending order of the DRB ID of the radio bearer for which packet duplication is set> <In the MAC device where the MAC CE is transmitted, the RLC device applies in ascending order of the DRB ID of the radio bearer for which a certain packet duplication is set> <Use the DRB ID value as it is> Here, L i The field can set whether to use the corresponding RLC device for packet duplicate transmission according to the bit value of the L i field to indicate each RLC device. For example, if the value of the L i field is "1", the corresponding RLC device is used for packet duplicate transmission, and if it is "0", the corresponding RLC device is not used for packet duplicate transmission. Which Li indicates which RLC device is a pre-set value, and one of the following values is applied.

[0055] <Apply in ascending (descending) order of the LCID of the master cell group, and then apply in ascending (descending) order of the secondary cell group LCID> <Pre-set the index corresponding to the RLC device and apply it in ascending order of the index> <Apply in ascending order of the priority of the corresponding logical channel. When the priorities are the same, align them in ascending order of the master cell group and LCID> By receiving the packet duplication activation / deactivation message, the terminal can determine which RLC device of which DRB to use for packet duplicate transmission and perform packet duplicate transmission.

[0056] Here, L iThe RLC devices that have the field are all the RLC devices configured in the DRB. In this case, for the radio bearer in Figure 3, all four configured RLC devices are L i Each of the fields can be set to indicate whether or not the RLC device is to be used for packet duplicate transmission. In another embodiment, only the RLC devices that have the "ul_duplication" field described in FIG. 3 set to "true" receive the corresponding L i It can also have fields. In this case, for the radio bearer of Figure 3, only the three RLC devices with "ul_duplication" set to "true" can have the Li field, and only these RLC devices can be set to whether or not to use packet duplication transmission.

[0057] The message format shown in FIG. 10 uses the same MAC CE format shown in FIG. 7, but the message format in FIG. 8 or FIG. 9 may also be used. It is also possible to use packet duplication activation / deactivation messages related to a common single radio bearer.

[0058] FIG. 11 is a diagram illustrating a method for a terminal to inform a base station of whether or not it has a packet duplication activation function according to an embodiment of the present invention. Since packet duplicate transmission is used to reduce latency or increase reliability such as packet loss probability, only certain terminals may support such a function.

[0059] In such a case, the terminal can inform the base station whether or not it supports the packet duplicate transmission function. At this time, the terminal may include support for the corresponding function in the "UE capability" message (1k-10). In addition, the "UE capability" message (1k-10) may include at least one of the following pieces of information related to packet duplication transmission of the terminal according to the present invention.

[0060] <Maximum number of RLC devices that can perform packet duplication in a single radio bearer> <Maximum number of RLC devices that can be configured for a single radio bearer> <Can packet duplication transmission be supported using three or more RLC devices?> <Maximum number of radio bearers that can be configured for packet duplication transmission using 3 or more RLC devices>

[0061] FIG. 12 is a flowchart illustrating an operation of performing packet duplicate transmission according to an embodiment of the present invention. Referring to FIG. 12, as in FIG. 1, multiple RLC devices may be configured for one radio bearer, one of which may be configured as a primary RLC device and the rest as secondary RLC devices. At this time, by activating packet duplication, the terminal can determine which RLC device to use and set up packet duplication.

[0062] If packet duplication is set for a radio bearer in step (1l-10), the process proceeds to step (1l-20) to determine whether packet duplication transmission for the corresponding bearer is actually activated. If packet duplication is activated, proceed to step (11-30), in which the transmitting PDCP device duplicates and then transmits the packet to the primary RLC device and all configured secondary RLC devices. If packet duplication is not activated, then proceed to step (11-40), where the transmitting PDCP device does not duplicate the packet and transmits the generated packet to the primary RLC device. If a split bearer is applied, when the data sent by the transmitter is below (or below) a certain threshold, the packet is transmitted only to the primary RLC, and when the data exceeds (or exceeds) the threshold, the packet is transmitted to both the primary device and the secondary device. However, if packet duplicate transmission is not activated, the packets are not duplicated.

[0063] FIG. 13 is a block diagram illustrating a schematic internal configuration of a terminal according to an embodiment of the present invention. Referring to FIG. 13, the terminal includes a transceiver unit (1m-10), a memory (1m-20) and a processor (1m-30). The terminal's transceiver unit (1m-10), memory (1m-20), and processor (1m-30) operate according to the terminal's communication method described above. However, the components of the terminal are not limited to the above examples. For example, the terminal may include more or fewer components than those described above. In addition, the transceiver (1m-10), the memory (1m-20) and the processor (1m-30) may be implemented in the form of a single chip.

[0064] The transceiver unit (1m-10) can transmit and receive signals to and from other network entities, such as base stations. Here, the signal may include control information and data. To this end, the transceiver unit (1m-10) may also be composed of an RF transmitter that up-converts and amplifies the frequency of the transmitted signal, and an RF receiver that low-noise amplifies the received signal and down-converts the frequency. However, this is only one embodiment of the transceiver unit (1m-10), and the components of the transceiver unit (1m-10) are not limited to an RF transmitter and an RF receiver. In addition, the transceiver unit (1m-10) can receive signals via a wireless channel, output the signals to the processor (1m-30), and transmit signals output from the processor (1m-30) via a wireless channel. For example, the transceiver units (1m-10) can receive system information from a base station and can receive a synchronization signal or a reference signal.

[0065] The memory (1m-20) stores programs and data necessary for the operation of the terminal. In addition, the memory (1m-20) can store control information or data included in a signal acquired by the terminal. For example, the memory (1m-20) can store information transmitted and received via the transceiver (1m-10), information generated via the processor (1m-30), and the like. The memory (1m-20) may be composed of a read only memory (ROM), a random access memory (RAM), a hard disk, a recording medium such as a compact disc read only memory (CD-ROM) and a digital versatile disc (DVD), or a combination of recording media.

[0066] The processor (1m-30) controls a series of steps so that the terminal operates according to the above-described embodiment. For example, the processor (1m-30) controls the signal flow between each block so as to execute the operations according to the described flowcharts. The process (1m-30) may also include circuit-specific or application-specific integrated circuits.

[0067] FIG. 14 is a block diagram illustrating generally the structure of a base station according to an embodiment of the present invention. Referring to FIG. 14, the base station includes a transceiver unit (1n-10), a memory (1n-20), and a processor (1n-30). The base station's transceiver unit (1n-10), memory (1n-20), and processor (1n-30) operate according to the above-mentioned base station communication method. However, the components of the base station are not limited to the above example. For example, the base station may include more or fewer components than those described above. In addition, the transceiver (1n-10), the memory (1n-20), and the processor (1n-30) may be implemented in the form of a single chip.

[0068] The transceiver units (1n-10) transmit and receive signals to and from other network entities, for example, terminals. Here, the signal may include control information and data. To this end, the transceiver units (1n-10) may also be configured with an RF transmitter that up-converts and amplifies the frequency of a signal to be transmitted, and an RF receiver that low-noise amplifies the received signal and down-converts the frequency. However, this is only one embodiment of the transceiver unit (1n-10), and the components of the transceiver unit (1n-10) are not limited to an RF transmitter and an RF receiver. In addition, the transceiver unit (1n-10) can receive a signal via a wireless channel, output the signal to the processor (1n-30), and transmit the signal output from the processor (1n-30) via a wireless channel. For example, the transceiver units 1n-10 can transmit system information to the terminals and can transmit synchronization signals or reference signals.

[0069] The memories (1n-20) store programs and data necessary for the operation of the base station. In addition, the memories 1n-20 can store control information or data included in a signal acquired by the base station. For example, the memory (1n-20) can store information transmitted and received via the transceiver (1n-10) and information generated via the processor (1n-30). The memory (1n-20) may be composed of a ROM, a RAM, a hard disk, a recording medium such as a CD-ROM, and a DVD, or a combination of recording media.

[0070] The processors (1n-30) control a series of steps to cause the base station to operate in accordance with the above-described embodiment of the present invention. The processors (1n-30) may also include circuit-specific or application-specific integrated circuits.

[0071] FIG. 15 is a block diagram illustrating a schematic structure of a radio bearer configured with packet duplicate transmission according to another embodiment of the present invention. Packet duplicate transmission means duplicating a packet at the sender and transmitting the packet over several paths.

[0072] Referring to FIG. 15, a radio bearer structure according to one embodiment shows a total of four RLC devices, RLC1 (2a-20), RLC2 (2a-30), RLC3 (2a-40), and RLC4 (2a-50), connected to one PDCP device (2a-10) to support several paths. However, this is only one example, and any number of RLC devices may be connected to the PDCP device, and the base station can set up a radio bearer structure according to the radio link and network structure.

[0073] In one embodiment of the radio bearer structure, the layer that performs packet duplication is the PDCP layer (2a-10), and after packet duplication is performed in the PDCP layer (2a-10), the duplicated packets can be transmitted to two or more different RLC devices to perform packet transmission independently. Since one radio bearer has one PDCP device regardless of packet duplication, a PDCP device also corresponds to one radio bearer ID. In one embodiment, the radio bearer including the PDCP1 (2a-10) is both a data radio bearer (DRB) and an SRB.

[0074] The RLC devices are also divided into a primary RLC device (2a-20) and secondary RLC devices (2a-30, 2a-40, 2a-50) according to their applications. The primary RLC device (2a-20) is a device that constantly transmits packets regardless of whether packet duplication is enabled. The secondary RLC devices (2a-30, 2a-40, 2a-50) are devices that transmit packets only when packet duplication is activated. In addition, the secondary RLC devices (2a-30, 2a-40, 2a-50) do not participate in uplink packet transmission according to the configuration method.

[0075] If a split bearer is applied, when the data sent by the transmitter is below (or below) a certain threshold, the packet is transmitted only to the primary RLC, and when the data exceeds (or exceeds) the threshold, the packet is transmitted to both the primary device and the secondary device. Packet duplicate transmission is also used to send packets of the same information over different paths to increase the probability of transmission. Therefore, if packets to be transmitted to different RLC devices are transmitted in the same MAC PDU (protocol data unit), the effect cannot be obtained. To this end, the cells that each RLC device can use are restricted, and packets transmitted to different RLC devices can be prevented from being transmitted in the same MAC PDU.

[0076] Referring to FIG. 15, RLC1 (2a-20) can only use cell 1 (2a-60), RLC2 (2a-30) can only use cell 2 (2a-70) and cell 3 (2a-80), RLC3 (2a-40) can only use cell 4 (2a-90), and RLC4 (2a-50) can only use cell 5 (2a-100). Each RLC device is mapped to a logical channel, and when a logical channel is configured, a list of cells that each logical channel can use can be configured. The list of cells that each such logical channel can use is called the cell restriction. The cell restriction can be applied in such a manner that after the terminal is allocated uplink resources, only the logical channel configured to use the corresponding cell in the logical channel prioritization (LCP) operation, i.e., the RLC device, participates. The detailed operation configuration may be included in at least one of a radio bearer configuration, an RLC bearer configuration, a PDCP configuration, and an RLC configuration of an RRC configuration message and transmitted to the UE.

[0077] FIG. 16 is a diagram illustrating a method for a base station to control activation and deactivation of packet duplication according to another embodiment of the present invention. Packet duplicate transmission increases radio resource consumption because the same packet is transmitted using two or more RLC units. It is undesirable to perform packet duplication all the time since it would result in inefficiencies in radio resource utilization. Therefore, packet duplicate transmission can be performed only when necessary. In a radio bearer for which packet duplication is configured, actually performing packet duplication is called activating packet duplication. Conversely, in a radio bearer for which packet duplication is set, not performing packet duplication is called deactivation of packet duplication.

[0078] In step (2b-10), the base station transmits a packet duplication activation / deactivation message to the terminal. At this time, the same type of message is used for activation and deactivation, and the activation and deactivation of packet duplication are distinguished according to a value included in the message. The packet duplication activation / deactivation message indicates which radio bearer associated packet duplication is to be activated or deactivated. In step (2b-20), after the terminal receives such a message, it applies packet duplication activation or deactivation according to the instruction contained in the message. The packet duplication activation / deactivation message may be sent in the form of a packet duplication activation / deactivation MAC CE to update the packet duplication state within the RRC configuration.

[0079] FIG. 17 is a diagram for explaining a method in which a base station controls activation and deactivation in cell carrier aggregation according to an embodiment of the present invention. In carrier aggregation, when two or more cells are used, the terminal must continuously use the transceiver of each cell, which increases power consumption. Therefore, if a terminal does not need to use multiple cells, the base station deactivates the terminal's cells. Alternatively, if a particular cell is not used for data transmission / reception for a certain period of time, it is determined that the cell is no longer required to be used and the cell is deactivated.

[0080] In step (2c-10), the base station transmits a cell activation / deactivation message to the terminal to activate / deactivate some cells. Both activation / deactivation by message transmission from the base station and deactivation by the terminal's judgment involve activation and deactivation of an SCell that is not a PCell or PSCell that is essential for the terminal to connect to the base station. In step (2c-20), when a cell activation / deactivation message is received or a particular cell is no longer used for transmission / reception for a certain period of time, the terminal applies activation or deactivation of the cell.

[0081] FIG. 18 is a diagram illustrating a method for applying a cell configuration when packet duplicate transmission is deactivated according to an embodiment of the present invention. Referring to FIG. 18, when packet duplication transmission is deactivated by the packet duplication activation / deactivation message, the transmitting PDCP device (2d-10) does not need to further duplicate packets and send them to multiple RLC devices. The transmitting PDCP device (2d-10) can send packets for transmission to either the primary RLC device (2d-20) or, depending on the defined split bearer operation, to one of the RLC devices (2d-20, 2d-30, 2d-40, 2d-50). If the terminal does not perform packet duplicate transmission, there is no need to apply the list of cells that each RLC device can use, as described in FIG. Therefore, when packet duplication transmission of a radio bearer configured with packet duplication is deactivated, as described in FIG. 18, all RLC devices of the corresponding radio bearer do not apply cell list restrictions and can use all configured cells (2d-60, 2d-70, 2d-80, 2d-90, 2d-100). In other words, no cell limits are applied.

[0082] Thus, the application or non-application of cell limits can be applied per RLC unit, i.e. per logical channel, or per radio bearer with packet duplication applied. In one embodiment, when the cell limit is applied on an RLC device basis, whether or not to apply the cell limit is determined based on whether packet duplication is activated for the corresponding RLC device. That is, the cell limit is applied only when the corresponding RLC device is used for packet duplicate transmission. Otherwise, no cell limit is applied.

[0083] In one embodiment, when the cell limit is applied on a per-radio bearer basis, if packet duplication transmission is deactivated for all secondary RLC devices belonging to the corresponding radio bearer, the cell limit is not applied. Alternatively, if only one RLC device is configured or activated for packet duplication, then no cell limit is applied since packet duplication transmission is not possible. In another embodiment, when the base station transmits a packet duplication activation / deactivation message to deactivate packet duplication transmission for a corresponding radio bearer, the cell restriction is not applied. Moreover, the cell limit is not applied if there is only one or fewer logical channels with packet duplication activated in the same cell group for a logical channel of a radio bearer with packet duplication configured.

[0084] FIG. 19 is a flow chart illustrating a method for applying cell limits for packet duplication according to one embodiment of the present invention. In step (2e-10), if packet duplication is configured in the radio bearer and a cell limit for each logical channel is configured, the terminal needs to determine whether to apply the cell limit of the RLC device. In step (2e-20), it is determined whether packet duplication in all secondary RLC devices is deactivated. Through such a judgment, the terminal decides whether to apply the cell restriction of the RLC device.

[0085] If packet duplication of all secondary RLC devices is deactivated, in step (2e-30), the terminal does not apply cell restriction and transmits all zero packets configured in the cell group. If packet duplication is activated for a secondary RLC device, then cell limiting is required, so proceed to step (2e-30) and apply cell limiting. In FIG. 19, a DRB is used as an example, but the same operation is also applied to an SRB.

[0086] FIG. 20 is a diagram for explaining an operation due to cell deactivation in a bearer with packet duplication set according to one embodiment. Referring to FIG. 20, it will be explained assuming radio bearer and cell limitations for packet duplication as described in FIG. As described above, for packet duplicate transmission, a list of cells that each logical channel can use, i.e., a cell limit, is set, and each RLC device participates in LCP operations and transmits packets only for cells that it can use. However, if all the cells set for use by a logical channel are deactivated by a deactivation message or the like, packets cannot be transmitted.

[0087] In one embodiment, if cell 4 (2f-90) that RLC3 (2f-40) is configured to use is deactivated, RLC3 will have no cell available to transmit packets. Therefore, in that case, the transmitting PDCP device (2f-10) will not send any more packets to the RLC3 after all. In addition, it is also possible to instruct the discard of packets waiting for transmission in RLC3. However, in some cases, the RLC3 has a packet for retransmission. The packet may be subject to no cell limit and may be subject to subsequent retransmissions. In one embodiment, RLC3 re-establishment may also be performed. Such an operation coincides with the operation of not using packet duplication in RLC3, ie, the packet duplication deactivation operation in RLC3.

[0088] FIG. 21 is a flowchart for explaining the operation of a transmitting PDCP device performing packet duplication in one embodiment of the present invention. As explained in FIG. 20, the cells that each RLC device, in other words, logical channel, can use may also be deactivated and unavailable for use. In that case, the packet duplication behavior of the transmitting PDCP is changed.

[0089] If packet duplication for the radio bearer is configured and activated in step (2g-10), the transmitting PDCP device proceeds to step (2g-20), where the transmitting PDCP device checks whether the RLC device used for packet duplication has at least one activated cell, and transmits the duplicated packet to the RLC device that has at least one activated cell. Through such an operation, unnecessary data processing operations of RLC devices that have no cells to use can be prevented.

[0090] FIG. 22 is a diagram illustrating an operation of a specific RLC device in response to deactivation of packet duplication transmission in a bearer in which packet duplication is set according to an embodiment of the present invention. Referring to FIG. 22, assume radio bearer and cell limitations for packet duplication as described in FIG. If a particular RLC device among the RLC devices in which the terminal is configured to participate in packet duplication is deactivated, the cells available to the corresponding logical channel will not transmit any more data. In this way, leaving some cells active but not in use results in a waste of radio resources. It is therefore efficient to allow such cells to be used by other cells of the same radio bearer.

[0091] In one embodiment, assume that packet duplication for RLC2 (2h-30) is deactivated (2h-110). In other words, RLC2 does not participate in packet duplicate transmission, and the transmitting PDCP device does not transmit duplicate packets to RLC2. At this time, cell 2 (2h-70) and cell 3 (2h-80) that are to be used by RLC2 can also be used by other RLC devices. In one embodiment, which RLC device uses the cells used by the deactivated RLC device is different. For example, the primary RLC device may use the cells used by the deactivated RLC device. Also, it is possible to use a cell used by a deactivated RLC device of another secondary RLC device in the same cell group that has the lowest or highest logical channel ID. Furthermore, after deactivating an RLC device through the RRC configuration of the base station, it is also possible to configure which RLC device uses the cell of the deactivated RLC device.

[0092] FIG. 23 is a diagram illustrating an operation of applying cell restriction when two or more cell groups are applied according to an embodiment of the present invention. Referring to FIG. 23, assume radio bearer and cell limitations for packet duplication as described in FIG.

[0093] In the dual connectivity structure, connections to multiple base stations are established on a cell group basis. That is, one cell group has one or more cells, and one cell group corresponds to one MAC device and one base station. In that case, logical channels of different cell groups, in other words RLC devices, will not transmit together since they use different MAC devices. If there is only one RLC unit performing packet duplication within a cell group, there is no need to maintain a cell limit for packet duplication as in FIG. Therefore, even if packet duplication transmission of a radio bearer is activated, if there is one or less RLC device used for packet duplication within the same cell group, the cell limitation is not applied.

[0094] In one embodiment, RLC1 (2i-20) and RLC2 (2i-30) operate in cell group 1 (2i-110), where RLC1 uses cell 1 (2i-60) and RLC2 (2i-30) uses cell 2 (2i-70) and cell 3 (2i-80). RLC3 (2i-40) and RLC4 (2i-50) operate in cell group 2 (2i-120), with RLC3 (2i-40) using cell 4 (2i-90) and RLC4 (2i-50) using cell 5 (2i-100). For example, if RLC3 (2i-40) is not used for packet duplicate transmission and RLC4 (2i-50) is used for packet duplicate transmission due to RRC settings or activation / deactivation settings, RLC4 (2i-50) will not use only cell 5 (2i-100), which is a cell that it can use, but will be able to use both cell 4 (2i-90) and cell 5 (2i-100) set in cell group 2.

[0095] FIG. 24 is a block diagram illustrating an internal configuration of a terminal according to another embodiment of the present invention. Referring to FIG. 24, the terminal includes a transceiver unit (2j-10), a memory (2j-20), and a processor (2j-30). The terminal's transceiver unit (2j-10), memory (2j-20), and processor (2j-30) operate according to the terminal's communication method described above. However, the components of the terminal are not limited to the above examples. For example, a terminal may include more or fewer components than those described above. In addition, the transceiver 2j-10, the memory 2j-20, and the processor 2j-30 may be implemented in the form of a single chip.

[0096] The transceiver unit (2j-10) transmits and receives signals to and from other network entities, e.g., base stations. Here, the signal may include control information and data. To this end, the transceiver unit (2j-10) may also be configured with an RF transmitter that up-converts and amplifies the frequency of a signal to be transmitted, and an RF receiver that performs low-noise amplification and down-converts the frequency of a received signal. However, this is only one embodiment of the transceiver unit (2j-10), and the components of the transceiver unit (2j-10) are not limited to an RF transmitter and an RF receiver.

[0097] In addition, the transceiver unit (2j-10) can receive signals via a wireless channel, output the signals to the processor (2j-30), and transmit signals output from the processor (2j-30) via a wireless channel. For example, the transceiver unit (2j-10) can receive system information from a base station and can receive a synchronization signal or a reference signal.

[0098] The memory (2j-20) stores programs and data necessary for the operation of the terminal. The memory 2j-20 can also store control information or data included in a signal acquired by the terminal. For example, the memory (2j-20) stores information transmitted and received via the transceiver (2j-10) and information generated via the processor (2j-30). The memory (2j-20) may be composed of a ROM, a RAM, a hard disk, a recording medium such as a CD-ROM, and a DVD, or a combination of recording media.

[0099] The processor (2j-30) controls a series of steps so that the terminal operates according to the above-described embodiment. For example, the processor (2j-30) controls the signal flow between each block so as to execute the operations according to the described flowcharts. The processors (2j-30) may also include circuit-specific or application-specific integrated circuits.

[0100] FIG. 25 is a block diagram illustrating generally the structure of a base station according to an embodiment of the present invention. Referring to FIG. 25, the base station includes a transceiver unit (2k-10), a memory (2k-20), and a processor (2k-30). The base station's transceiver unit (2k-10), memory (2k-20), and processor (2k-30) operate according to the above-mentioned base station communication method. However, the components of the base station are not limited to the above example. For example, the base station may include more or fewer components than those described above. In addition, the transceiver 2k-10, the memory 2k-20, and the processor 2k-30 may be implemented in the form of a single chip.

[0101] The transceiver unit (2k-10) transmits and receives signals to and from other network entities, for example, terminals. Here, the signal may include control information and data. To this end, the transceiver unit (2k-10) may also be configured with an RF transmitter that up-converts and amplifies the frequency of the signal to be transmitted, and an RF receiver that performs low-noise amplification and down-converts the frequency of the received signal. However, this is only one embodiment of the transceiver unit (2k-10), and the components of the transceiver unit (2k-10) are not limited to an RF transmitter and an RF receiver.

[0102] In addition, the transceiver unit (2k-10) can receive a signal via a wireless channel, output the signal to the processor (2k-30), and transmit the signal output from the processor (2k-30) via a wireless channel. For example, the transceiver unit 2k-10 can transmit system information to the terminal, and can also transmit a synchronization signal or a reference signal.

[0103] The memory (2k-20) stores programs and data necessary for the operation of the base station. In addition, the memory 2k-20 can store control information or data included in a signal acquired by the base station. For example, the memory (2k - 20) can store information transmitted and received via the transceiver unit (2k - 10), information generated via the processor (2k - 30), and the like. The memory (2k - 20) can also be constituted by a recording medium such as a ROM, a RAM, a hard disk, a CD-ROM, and a DVD, or a combination of recording media.

[0104] The processor (2k - 30) controls a series of steps so that the base station operates according to the foregoing embodiments of the present invention. Also, the processor (2k - 30) may include a circuit-specific or application-specific integrated circuit.

[0105] FIG. 26 is a diagram showing an activation / deactivation message format for packet duplication according to another embodiment of the present invention. Referring to FIG. 26, the activation / deactivation message for packet duplication is also in the MAC CE format. In one embodiment, the activation / deactivation message for packet duplication includes a DRB index (1o - 10) and L i (i = 1, 2, 3, 4) fields (1o - 20, 1o - 30, 1o - 40, 1o - 50). At this time, the DRB index is a preset value and is applied to one of the following values.

[0106] <Explicitly indicate in the DRB setting when the base station is set> <Apply in ascending order of the DRB ID of the radio bearer for which packet duplication is set> <Apply in ascending order of the DRB ID of the radio bearer for which packet duplication is set and there is an RLC device in the MAC device where the MAC CE is transmitted> <Use the DRB ID value as it is> Here, L i The field indicates each RLC device, but L i Whether the corresponding RLC device is used for packet duplication transmission can be set according to the bit value of the field. For example, L iIf the value of the field is "1", the corresponding RLC device is used for packet retransmission; if it is "0", the corresponding RLC device is not used for packet retransmission. Which Li indicates which RLC device is a pre-set value and is applied to one of the following values.

[0107] <Ascending (descending) order application of the LCID of the master cell group, and then ascending (descending) order application of the LCID of the secondary cell group> <Pre-set the index corresponding to the RLC device and in ascending order of the index> <Ascending order application of the priority of the corresponding logical channel. When the priorities are the same, arrange them in ascending order of the LCID of the master cell group> By receiving the packet duplication activation / deactivation message, the terminal can determine which RLC device of which DRB to use for packet retransmission and perform packet retransmission.

[0108] Here, the RLC device with the L i field is also all the RLC devices set for the DRB. At this time, in the case of the radio bearer in FIG. 3, all four set RLC devices can have the L i field, and whether to use the RLC device for packet retransmission can be set for each RLC device. In other embodiments, only the RLC device in which the "ul_duplication" field described in FIG. 3 is set to "true" can also have the corresponding L i field. In that case, in the case of the radio bearer in FIG. 3, only three RLC devices with "ul_duplication" set to "true" can have the Li field, and whether to use it for packet retransmission can be set only for the RLC device having the Li field.

[0109] In yet another embodiment, the number of RLC devices configured in the DRB with packet duplicate transmission is L. i This also matches the number of fields. In the embodiment of FIG. i There were a total of four fields set up (1o-20, 1o-30, 1o-40, 1o-50). In this manner, the fact that a total of four Li fields are set indicates that the number of RLC devices configured in the corresponding DRB is four. For example, if the number of RLC devices configured for the DRB is three, i The field is L 1 , L 2 , L 3 It only has fields. Then, a reserved field (R (reserved)) (1o-60) may be included to match the byte length, which may mean filling the R bits so that the length of the packet duplication activation / deactivation message shown in Figure 26 is a byte long, i.e., a multiple of 8 bits. The value of the R bit can be set to a pre-configured value or the terminal can ignore it.

[0110] In the dual connectivity architecture, the packet duplication activation / deactivation message transmitted to a particular cell group does not indicate whether all RLC devices are used for packet duplication transmission. For example, a MAC CE transmitted to a master cell group (MCG) indicates whether or not to use packet duplication transmission only for RLC devices configured in the MCG. In this case, the number of Li fields corresponds to the number of RLC devices, which indicates whether or not the corresponding RLC device is used for packet duplication transmission in the corresponding MAC CE. For example, if the number of RLC devices configured in the MCG for a radio bearer with packet duplication transmission is two, i The number of fields can be two, and the remaining field can be an R field.

[0111] In another embodiment, the Li field is set to the maximum number of RLC devices that can be set for each radio bearer, and the actual L is set only for the RLC devices that are actually set. i The field can determine whether or not to use packet duplication. For example, if up to four RLC devices can be set, i The field is L 1 , L 2 , L 3 , L 4 Has fields (1o-10, 1o-20, 1o-30, 1o-40). If the number of RLC devices actually configured is three, then L 1 , L 2 , L 3 A field is used to indicate whether the corresponding RLC device is used for packet duplicate transmission. However, L 4 The field may be set to a pre-configured value of "0" or "1" and ignored by the terminal since there is no corresponding RLC device.

[0112] The packet duplication activation / deactivation message of FIG. 26 has a fixed length of 1 byte, and therefore also results in a fixed-size MAC CE. In that case, the fixed length MAC CE may have a MAC sub-header associated with it, which will be described below in FIG.

[0113] FIG. 27 illustrates a packet duplication activation / deactivation message format according to yet another embodiment of the present invention. Referring to FIG. 27, the packet duplication activation / deactivation message is also in MAC CE format. In FIG. 27, the DRB index and the L corresponding to the RLC device described in FIG. iThree messages (1p-10, 1p-20, 1p-30) of a format having a field and an R field which is a spare bit for matching the byte length are superimposed to form one MAC CE. However, this is only an example, and any number of MAC CEs may be superimposed. The number of MAC CEs to be superimposed can also be variably determined by the base station only for the radio bearer in which the base station sets packet duplication.

[0114] When the number of radio bearers controlling packet duplicate transmission included in the packet duplication activation / deactivation message in FIG. 27 is variable, it becomes a variable-size MAC CE. In that case, the variable-size MAC CE can have a MAC sub-header related to the variable-size MAC CE described in FIG. 29. However, L i Embodiments of the application method related to the field and the R field are the same as the example described in FIG. 26. At this time, packet duplication may be allowed for the RLC device of the radio bearer indicated by the DRB index. Also, the DRB index is a preset value and is applied to one of the following values.

[0115] <Explicitly indicate in DRB setting when setting up the base station> <Apply in ascending order of DRB ID of the radio bearer in which packet duplication is set> <Apply in ascending order of DRB ID of the radio bearer in which packet duplication is set and there is an RLC device in the MAC device to which the MAC CE is transmitted> <Use the DRB ID value as it is> Here, L i The field indicates each RLC device, and whether or not the corresponding RLC device is used for packet duplicate transmission can be set according to the bit value of the Li field. For example, if the value of the Li field is "1", the corresponding RLC device is used for packet duplicate transmission, and if it is "0", the corresponding RLC device is not used for packet duplicate transmission. Which Li indicates which RLC device is a pre-configured value and can be one of the following:

[0116] <Apply the LCID of the master cell group in ascending (descending) order, then apply the LCID of the secondary cell group in ascending (descending) order> Set the index corresponding to the RLC device in advance, and sort the index in ascending order. <Applied in ascending order of priority of the corresponding logical channel, if the priority is the same, sorted in ascending order of master cell group and LCID> By receiving the packet duplication activation / deactivation message, the terminal can determine which RLC device of which DRB to use for packet duplication transmission and perform packet duplication transmission.

[0117] Here, L i The RLC devices that have the field are all the RLC devices configured in the DRB. In this case, in the case of the radio bearer in Figure 3, all four RLC devices configured are L i A field may be included, and whether or not the RLC device is used for packet duplicate transmission may be set for each RLC device. In another embodiment, only the RLC devices that have the "ul_duplication" field described in FIG. 3 set to "true" receive the corresponding L i It can also have fields. In this case, for the radio bearer of Figure 3, only three RLC devices with "ul_duplication" set to "true" can have Li fields, and only for the RLC devices having the Li fields, it can be set whether or not to use packet duplication transmission.

[0118] In yet another embodiment, the number of RLC devices configured in the DRB with packet duplicate transmission is L. i This also matches the number of fields. In the embodiment of FIG. iFour fields were set for every radio bearer. This indicates that the number of RLC devices configured in the corresponding DRB is four. For example, if the number of RLC devices configured for the DRB is three, i The field is L 1 , L 2 , L 3 It only has fields. Then, a reserved field (R(reserved)) may be included to match the byte length, which may mean filling the R bits so that the length of the packet duplication activation / deactivation message shown in Figure 27 is a multiple of a byte length, i.e., 8 bits. The value of the R bit can be set to a pre-configured value or the terminal can ignore it.

[0119] In the dual connectivity architecture, the packet duplication activation / deactivation message transmitted to a specific cell group does not indicate whether all RLC devices are used for packet duplication transmission. For example, the MAC CE transmitted to the MCG indicates whether or not to use packet duplication transmission only for the RLC devices configured in the MCG. In that case, L i The number of fields corresponds to the number of RLC devices that indicate whether or not the corresponding RLC device is used for packet duplication transmission in the corresponding MAC CE. For example, if the number of RLC devices configured in the MCG for a radio bearer with packet duplication transmission is two, i The number of fields becomes two, and the remaining field becomes an R field.

[0120] In another embodiment, the maximum number of RLC units that can be configured for each radio bearer is L. i The actual LLC field is set and only those RLC devices that have actually been set are i A field can be used to determine whether or not to use packet duplication. For example, if up to four RLC devices can be configured, the Li field should be set to L 1 , L 2 , L 3 , L 4 It has a field. If the number of RLC devices actually configured is three, then L 1 , L 2 , L 3 The field is used to indicate whether the corresponding RLC device is used for packet duplicate transmission. However, L 4 The field may be set to a pre-configured value of "0" or "1" and ignored by the terminal since there is no corresponding RLC device.

[0121] FIG. 28 illustrates a packet duplication activation / deactivation message format according to yet another embodiment. Referring to FIG. 28, the packet duplication activation / deactivation message is also in MAC CE format. In FIG. 28, the DRB index and the L corresponding to the RLC device described in FIG. 26 are i Three messages having a format with a field (1q-10, 1q-20, 1q-30) are superimposed to form one MAC CE. However, this is merely an example, and any number of MAC CEs may be superimposed.

[0122] How many MAC CEs are overlapped can be variably determined only for the radio bearers for which the base station sets packet overlapping. If the number of radio bearers controlling packet duplication transmission included in the packet duplication activation / deactivation message of FIG. 28 is variable, the MAC CE will be of variable length. In that case, the variable length MAC CE has a MAC sub-header associated with it as described in FIG. However, L i The application method embodiment related to the fields is the same as the example described in FIG.

[0123] In the embodiment of FIG. 28, a reserved (R) field is used to align the byte length of the entire message at the very end of the MAC CE (1q-40, 1q-41, 1q-42). That is, the previous DRB index, L i The field lists values ​​related to all radio bearers indicated in the corresponding packet duplication activation / deactivation message. The method of applying the DRB index and Li field shown in the embodiment of FIG. 28 is the same as that in FIG.

[0124] FIG. 29 illustrates a MAC sub-header format for a variable length MAC CE according to one embodiment of the present invention. The MAC subheader is located before the MAC CE and serves to indicate what information the following MAC CE contains. A variable length MAC CE may mean a MAC CE in which the length of the MAC CE is not defined.

[0125] The MAC subheader contains an L field (1r-40) to signal the length of the MAC CE that follows. In addition, the MAC subheader has a reserved field (R) (1r-10), an F field (1r-20), and a logical channel identifier (LCID) field (1r-30). The F field is a field that indicates the length of the L field. When the F field is "0", the L field is 1 byte, and when the F field is "1", the L field is 2 bytes. In the embodiment of FIG. 29, the F field has a value of "0", indicating that the L field has a length of 1 byte. The LCID field is a value that indicates the type of MAC CE that follows. For example, if a packet duplication activate / deactivate message is subsequently included, the LCID field has an LCID value that indicates the packet duplication activate / deactivate message.

[0126] FIG. 30 illustrates a MAC subheader format for a fixed length MAC CE according to one embodiment of the present invention. The MAC subheader is located before the MAC CE and serves to indicate what information the following MAC CE contains. Fixed length MAC CE may mean that the length of the MAC CE is fixed. Therefore, the MAC subheader of the fixed length MAC CE does not need the L field (1r-40) shown in FIG. Therefore, the subheader of the fixed length MAC CE has a reserved field (R (reserved)) (1s-10), an F field (1s-20), and an LCID field (1s-30). The F field is a field that indicates the length of the L field, but in the embodiment of Figure 30, since the L field is not necessary, the F field is set to a value of "0" and the terminal ignores the F field. The LCID field is a value that indicates the type of MAC CE that follows. For example, if a packet duplication activation / deactivation message is subsequently included, the LCID field has an LCID value that indicates the packet duplication activation / deactivation message.

[0127] The methods according to the embodiments described in the claims or specification of the present disclosure may be embodied in hardware, software, or a combination of hardware and software. When embodied in software, a computer readable recording medium storing one or more programs (software modules) may be provided. One or more programs stored on a computer-readable medium are configured for execution by one or more processors in an electronic device. The one or more programs contain instructions that cause an electronic device to perform a method according to the claims or embodiments described in the present disclosure.

[0128] Such programs (software modules, software) may also be stored in RAM, non-volatile memory including flash memory, ROM, Electrically Erasable Programmable ROM (EEPROM), magnetic disc storage devices, compact disc read only memory (CD-ROM); digital versatile discs (DVDs), or other forms of optical storage devices, magnetic cassettes. Or, it may be stored in a memory configured by a combination of some or all of them. Also, each of the configuration memories may be included in multiples.

[0129] The program may also be stored in an attachable storage device that can be accessed via a communication network such as the Internet, an intranet, a local area network (LAN), a wide LAN (WLAN) or a storage area network (SAN), or a combination thereof. Such a storage device may be connected via an external port to a device implementing embodiments of the present disclosure. Also, separate storage devices over a communications network may be connected to devices implementing embodiments of the present disclosure.

[0130] In the specific embodiments of the present disclosure described above, elements included in the invention are expressed as singular or plural in accordance with the specific embodiments presented. However, the singular or plural expressions have been selected for convenience of explanation as appropriate to the context presented, and the present disclosure is not limited to singular or plural components, and components expressed in the plural may be configured in the singular, or components expressed in the singular may be configured in the plural. On the other hand, the embodiments of the present disclosure disclosed in this specification and the drawings are merely specific examples presented to easily explain the contents of the present disclosure and to aid in the understanding of the present disclosure, and are not intended to limit the scope of the present disclosure. In other words, it is obvious to a person skilled in the art in the technical field to which the present disclosure pertains that other modified examples based on the technical ideas of the present disclosure can be implemented. Furthermore, the above-described embodiments may be combined with each other as necessary. For example, parts of different embodiments of the present disclosure may be combined with each other to operate a base station and a terminal. In addition, the above embodiment may operate in various communication systems such as an FDD LTE system, a TDD LTE system, a 5G system, or an NR system, and other variations based on the technical ideas of the above embodiment may be implemented. [Explanation of symbols]

[0131] 1m-10, 1n-10, 2j-10, 2k-10 Transmitter / Receiver 1m-20, 1n-20, 2j-20, 2k-20 memory 1m-30, 1n-30, 2j-30, 2k-30 processors

Claims

1. In a terminal for performing packet duplicate transmission in a wireless communication system, The terminal includes: A transmitting / receiving unit; at least one processor coupled to the transceiver; The at least one processor Receive a Medium Access Control (MAC) Control Element (CE) from a base station, the Medium Access Control (MAC) Control Element (CE) instructing activation or deactivation of replication associated with multiple secondary Radio Link Control (RLC) entities of one Data Radio Bearer (DRB); Here, the MAC CE indicating the activation or deactivation of the duplication includes a DRBID and a plurality of RLC fields, The plurality of RLC fields includes an RLC field, The RLC field indicates an activation state or a deactivation state of a Packet Data Convergence Protocol (PDCP) replication associated with a secondary RLC entity corresponding to the RLC field among the plurality of secondary RLC entities; When a MAC CE indicating activation or deactivation of the duplication indicates activation of PDCP duplication related to at least one secondary RLC entity among the plurality of secondary RLC entities, the terminal duplicates a PDCP packet and transmits the PDCP packet to a primary RLC entity and the at least one secondary RLC entity.

2. The terminal of claim 1, wherein the at least one processor transmits capability information indicating whether or not duplicate transmission using more than two RLC entities is supported to a base station.

3. The terminal of claim 1, wherein the plurality of RLC fields are identified in ascending order of logical channel IDs in the order of a master cell group, followed by a secondary cell group.

4. The at least one processor activates a PDCP replica associated with the secondary RLC entity corresponding to the RLC field when the RLC field is set to '1'; 2. The terminal of claim 1, wherein when the RLC field is set to '0', the terminal deactivates PDCP replication associated with the secondary RLC entity corresponding to the RLC field.

5. The terminal of claim 1, wherein the primary RLC entity is not deactivated.

6. 2. The terminal of claim 1, wherein the at least one processor instructs, via a PDCP entity, a deactivated RLC entity to discard all duplicated PDCP packets.

7. The at least one processor receiving logical channel configuration information from a base station, the logical channel configuration information including information associated with at least one cell used by the logical channel; The terminal of claim 1, characterized in that if any of a plurality of RLC entities including the plurality of secondary RLC entities and the primary RLC entity are deactivated or only one RLC entity is activated, the terminal determines not to apply the logical channel configuration information associated with the at least one cell used by the logical channel.

8. The at least one processor receiving logical channel configuration information from a base station, the logical channel configuration information including information related to a cell restriction mapped to the logical channel; The terminal of claim 1, characterized in that if there is no activated RLC entity among a plurality of RLC entities including the plurality of secondary RLC entities and a primary RLC entity in a cell group, or if there is only one RLC entity, the cell restriction is not applied regardless of information related to the cell restriction mapped to the logical channel.

9. A method for performing packet duplicate transmission by a terminal in a wireless communication system, comprising: The method comprises: receiving a Medium Access Control (MAC) Control Element (CE) from a base station, the Medium Access Control (MAC) Control Element (CE) instructing activation or deactivation of replication associated with a plurality of secondary Radio Link Control (RLC) entities of one Data Radio Bearer (DRB); Here, the MAC CE indicating the activation or deactivation of the duplication includes a DRBID and a plurality of RLC fields, The plurality of RLC fields includes an RLC field, The RLC field indicates an activation state or a deactivation state of a Packet Data Convergence Protocol (PDCP) replication associated with a secondary RLC entity corresponding to the RLC field among the plurality of secondary RLC entities; and if the MAC CE indicating the activation or deactivation of the duplication indicates activation of PDCP duplication associated with at least one secondary RLC entity among the plurality of secondary RLC entities, duplicating a PDCP packet and transmitting the PDCP packet to a primary RLC entity and the at least one secondary RLC entity.

10. The method comprises:

10. The method of claim 9, further comprising transmitting capability information indicating whether or not duplicate transmission using more than two RLC entities is supported to a base station.

11. The method of claim 9, wherein the RLC fields are identified in ascending order of logical channel ID in the order of a master cell group, followed by a secondary cell group.

12. The method comprises: activating a PDCP replica associated with the secondary RLC entity corresponding to the RLC field when the RLC field is set to '1'; 10. The method of claim 9, further comprising: when the RLC field is set to '0', deactivating a PDCP replica associated with the secondary RLC entity corresponding to the RLC field.

13. 10. The method of claim 9, wherein the primary RLC entity is not deactivated.

14. 10. The method of claim 9, further comprising the step of instructing, via the PDCP entity, the deactivated RLC entity to discard all duplicated PDCP packets.

15. The method comprises: receiving logical channel configuration information from a base station, the logical channel configuration information including information associated with at least one cell used by the logical channel; and determining not to apply the logical channel configuration information associated with the at least one cell used by the logical channel if any of a plurality of RLC entities, including the plurality of secondary RLC entities and a primary RLC entity, is deactivated or if only one RLC entity is activated.

16. The method comprises: The method further includes receiving logical channel configuration information from a base station, the logical channel configuration information including information related to a cell restriction mapped to the logical channel; The method according to claim 9, characterized in that, if there is no activated RLC entity among a plurality of RLC entities including the plurality of secondary RLC entities and a primary RLC entity in a cell group, or if there is only one RLC entity, the cell restriction is not applied regardless of information related to the cell restriction mapped to the logical channel.

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