Method and apparatus for performing dual connectivity for UE in a wireless communication system

Abstract

A communication method and system for integrating a fifth generation (5G) communication system for supporting a higher data rate than a fourth generation (4G) system with Internet of Things (IoT) technology. The present disclosure can be applied to smart services based on 5G communication technology and IoT-related technologies, such as smart homes, smart buildings, smart cities, smart cars, connected cars, healthcare, digital education, smart retail, safety and security services. The present disclosure relates to a method and apparatus for performing dual connectivity by a user equipment in a wireless communication system.

Description

Technical Field

[0001] The present disclosure relates to a method and apparatus for performing dual connectivity by a user equipment in a wireless communication system. Background Art

[0002] In order to meet the demand for increased wireless data traffic since the deployment of the fourth generation (4G) communication system, efforts have been made to develop an improved fifth generation (5G) or quasi-5G communication system. Therefore, the 5G or quasi-5G communication system is also called "super 4G network" or "post-long term evolution (LTE) system". The 5G communication system is considered to be implemented in a higher frequency (mmWave) band, such as the 60GHz band, in order to achieve higher data rates. In order to reduce the propagation loss of radio waves and increase the transmission distance, technologies such as beamforming, massive multiple input multiple output (MIMO), full-dimensional multiple input multiple output (FD-MIMO), array antennas, analog beamforming, and massive antennas are discussed in the 5G communication system. In addition, in the 5G communication system, system network improvements are being developed based on advanced small cells, cloud radio access networks (RAN), ultra-dense networks, device-to-device (D2D) communications, wireless backhaul, mobile networks, collaborative communications, coordinated multi-point (CoMP), receiving-end interference elimination, etc. In 5G systems, hybrid frequency shift keying (FSK) and quadrature amplitude modulation (QAM) (FQAM) and sliding window superposition coding (SWSC) have been developed as advanced coded modulation (ACM), and filter bank multi-carrier (FBMC), non-orthogonal multiple access (NOMA) and sparse code multiple access (SCMA) as advanced access technologies.

[0003] The Internet, a human-centered connected network in which humans generate and consume information, is now evolving toward the Internet of Things (IoT), in which distributed entities (such as things) exchange and process information without human intervention. The Internet of Everything (IoE) has emerged, which is a combination of IoT technology and big data processing technology through connection with cloud servers. As IoT implementation requires technical elements such as "sensing technology", "wired / wireless communication and network infrastructure", "service interface technology" and "security technology", sensor networks, machine-to-machine (M2M) communication, machine-type communication (MTC), etc. have been recently studied. Such an IoT environment can provide intelligent Internet technology services to create new value for human life by collecting and analyzing data generated between connected things. IoT can be applied to a variety of fields including smart homes, smart buildings, smart cities, smart cars or connected cars, smart grids, healthcare, smart appliances and advanced medical services through the integration and combination between existing information technology (IT) and various industrial applications.

[0004] In line with this, various attempts have been made to apply 5G communication systems to IoT networks. For example, technologies such as sensor networks, machine type communications (MTC), and machine-to-machine (M2M) communications can be implemented through beamforming, MIMO, and array antennas. Cloud radio access networks (RANs) as an application of the above-mentioned big data processing technologies can also be considered as an example of the fusion of 5G technologies and IoT technologies.

[0005] Meanwhile, in a communication system, various types of studies are being conducted on schemes for transmitting uplink control channels. In particular, schemes for transmitting a physical uplink control channel (PUCCH), a physical uplink shared channel (PUSCH), etc. are discussed in many different ways.

[0006] The above information is provided as background information only to assist in understanding the present disclosure. No determination has been made, and no assertion is made, as to whether any of the above may be applicable as prior art to the present disclosure. Summary of the invention

[0007]

Technical issues

[0008] A user equipment (UE) capable of dual connectivity with LTE and New Radio (NR) can send and receive data to and from LTE and NR cells, respectively. Based on the UE's capabilities and the permissions in a specific frequency band combination for dual connectivity, the UE can be configured to support only one uplink (UL) transmission.

[0009] Various aspects of the present disclosure are intended to at least solve the above-mentioned problems and / or disadvantages and to provide at least the following advantages. Therefore, one aspect of the present disclosure is to provide a method and an apparatus for performing uplink transmission by a UE according to whether the UE has a dynamic power sharing capability when a long-term evolution time division duplex (LTE TDD) is a primary cell and a NR is a secondary cell.

[0010] LTE downlink reception or NR downlink reception of the UE may be affected by interference, and downlink reception performance may be degraded due to interference attributable to inter-modulation (IM) or harmonics, which occurs due to LTE uplink transmission or NR uplink transmission performed by the UE based on a specific frequency band combination of frequencies used for LTE and NR transmission and reception.

[0011] Another aspect of the present disclosure is to provide a method and apparatus for avoiding interference effects on LTE downlink reception or NR downlink reception caused by LTE uplink or NR uplink transmission when LTE frequency division duplex (FDD) is a primary cell and NR is a secondary cell.

[0012] Additional aspects will be set forth in part in the description which follows and, in part, will be obvious from the description, or may be learned by practice of the presented embodiments.

[0013]

Solution

[0014] According to one aspect of the present disclosure, a method performed by a terminal is provided. The method includes: receiving configuration information associated with dual uplink transmission from a base station, the configuration information being associated with uplink transmission timing of a master cell group (MCG); identifying that capability information sent to the base station does not indicate the capability of the configuration information of dual uplink transmission; in the case where the uplink transmission of the SCG overlaps with the uplink transmission of the MCG, discarding the uplink transmission of the secondary cell group (SCG); and sending the uplink transmission of the MCG to the base station based on the configuration information.

[0015] According to another aspect of the present disclosure, a terminal is provided. The terminal includes a transceiver and at least one processor, the processor being configured to control the transceiver to receive configuration information associated with dual uplink transmission from a base station, the configuration information being associated with uplink transmission timing of a primary cell group (MCG), identify that capability information sent to the base station does not indicate the capability of the configuration information of dual uplink transmission, control the transceiver to discard the uplink transmission of the secondary cell group (SCG) when the uplink transmission of the SCG overlaps with the uplink transmission for the MCG, and control the transceiver to send the uplink transmission of the MCG to the base station based on the configuration information.

[0016] According to another aspect of the present disclosure, a method performed by a base station is provided. The method includes sending configuration information associated with dual uplink transmission to a terminal and receiving configuration information associated with uplink transmission timing of a primary cell group (MCG) from a base station, identifying that capability information received from the terminal does not indicate capability of the configuration information of dual uplink transmission, and receiving uplink transmission for the MCG from the terminal based on the configuration information, wherein, in the case where the uplink transmission of the SCG overlaps with the uplink transmission of the MCG, the uplink transmission for the secondary cell group (SCG) is discarded by the terminal.

[0017] According to another aspect of the present disclosure, a base station is provided. The base station includes a transceiver and at least one processor, the processor being configured to control the transceiver to send configuration information associated with dual uplink transmission to a terminal and receive configuration information associated with uplink transmission timing of a primary cell group (MCG) from the base station, identify that capability information received from the terminal does not indicate capability of configuration information for dual uplink transmission, and control the transceiver to receive uplink transmission based on configuration information MCG from the terminal when uplink transmission of the SCG overlaps with uplink transmission of the MCG, wherein uplink transmission of the secondary cell group (SCG) is discarded by the terminal.

[0018]

Beneficial Effects

[0019] According to an embodiment of the present disclosure, a method and apparatus for solving interference problems in a wireless communication system by a UE having dual connectivity may be provided.

[0020] Other aspects, advantages, and salient features of the present disclosure will become apparent to those skilled in the art from the following detailed description, which, taken in conjunction with the accompanying drawings, discloses various embodiments of the present disclosure. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] The above and other aspects, features and advantages of certain embodiments of the present disclosure will become more apparent from the following description in conjunction with the accompanying drawings, in which:

[0022] Figure 1 is a diagram showing a basic structure of a time-frequency domain in an LTE system according to an embodiment of the present disclosure;

[0023] Figure 2 is a diagram showing an operation example of a subframe in an LTE TDD frame according to an embodiment of the present disclosure;

[0024] Figure 3 is a diagram showing another operation example of a subframe in an LTE TDD frame according to an embodiment of the present disclosure;

[0025] Figure 4 is a diagram showing an example of multiplexing and transmitting 5G services in one system according to an embodiment of the present disclosure;

[0026] Figure 5 is a diagram showing an example of a configuration of a communication system to which the present disclosure is applied according to an embodiment of the present disclosure;

[0027] Figure 6 is a diagram showing a first problem situation to be solved according to an embodiment of the present disclosure;

[0028] Figure 7 is a diagram illustrating UL transmission according to an embodiment of the present disclosure;

[0029] Figure 8 is a diagram illustrating UL transmission according to an embodiment of the present disclosure;

[0030] Fig. 9A is a diagram illustrating the operation of a base station (BS) according to an embodiment of the present disclosure;

[0031] Fig. 9B is a diagram illustrating the operation of a UE according to an embodiment of the present disclosure;

[0032] Fig.10 is a diagram showing a second problem situation to be solved according to an embodiment of the present disclosure;

[0033] Fig.11 is a diagram showing a first interference situation to be solved according to an embodiment of the present disclosure;

[0034] Fig.12 is a diagram showing a second interference situation to be solved according to an embodiment of the present disclosure;

[0035] Fig.13A is a diagram showing a BS process according to an embodiment, which BS process is proposed according to an embodiment of the present disclosure;

[0036] Fig. 13B is a diagram showing a UE process according to an embodiment, which UE process is proposed according to an embodiment of the present disclosure;

[0037] Fig.14 is a diagram showing a configuration of a BS according to an embodiment, the configuration of the BS being proposed according to an embodiment of the present disclosure; and

[0038] Fig.15 is a diagram showing a configuration of a UE according to an embodiment, the configuration of the UE being proposed according to an embodiment of the present disclosure;

[0039] Throughout the drawings, like reference numerals will be understood to refer to like parts, components and structures. DETAILED DESCRIPTION

[0040] The following description with reference to the accompanying drawings is provided to assist in a comprehensive understanding of the various embodiments of the present disclosure as defined by the claims and their equivalents. It includes various specific details that aid in understanding, but these are considered to be exemplary only. Therefore, it will be appreciated by those of ordinary skill in the art that various changes and modifications may be made to the various embodiments described herein without departing from the scope and spirit of the present disclosure. In addition, for the sake of clarity and conciseness, descriptions of well-known functions and structures may be omitted.

[0041] The terms and words used in the following description and claims are not limited to the bibliographical meanings, but are merely used by the inventor to enable a clear and consistent understanding of the present disclosure. Therefore, it will be apparent to those skilled in the art that the following description of various embodiments of the present disclosure is for illustrative purposes only and not for limiting the present disclosure as defined by the appended claims and their equivalents.

[0042] It should be understood that the singular forms "a," "an," and "the" include plural referents unless the context clearly dictates otherwise. Thus, for example, reference to "a component surface" includes reference to one or more of such surfaces.

[0043] In the present disclosure, it will be understood that each block of the flowchart illustration and the combination of blocks in the flowchart illustration can be operated by computer program instructions. These computer program instructions can be installed on a processor of a general-purpose computer, a special-purpose computer, or other programmable data processing device, so that the instructions executed by the processor of the computer or other programmable data processing device create a method for operating the functions specified in the flowchart (multiple) blocks. These computer program instructions can also be stored in a computer-usable or computer-readable memory, which can instruct the computer or other programmable data processing equipment to implement the functions in a specific manner, so that the instructions stored in the computer-usable or computer-readable memory generate a product including an instruction method for implementing the functions specified in the flowchart (multiple) blocks. The computer program instructions can also be loaded on a computer or other programmable data processing device so that a series of operating steps are performed on the computer or programmable data processing equipment to generate a computer-operated process, so that the instructions of the execution computer or programmable data processing equipment provide steps for operating the functions described in the flowchart (multiple) blocks.

[0044] In addition, each block of the flowchart diagram can represent a part of a module, segment or code, which includes one or more executable instructions for realizing (multiple) specified logical functions. It should also be noted that in some optional embodiments, the functions mentioned in the box can occur out of order. For example, the two blocks shown in succession can actually run basically at the same time, or the blocks can sometimes run in reverse order, depending on the functions involved.

[0045] The term "unit" used in the embodiment means software or hardware components, such as field programmable gate array (FPGA) or application specific integrated circuit (ASIC), and "unit" performs specific tasks. However, the term "unit" does not mean that it is limited to software or hardware. "Unit" can be advantageously configured to reside on an addressable storage medium, and is configured to operate on one or more processors. Therefore, "unit" can include, for example, components, such as software components, object-oriented software components, class components and task components, processes, functions, attributes, processes, subroutines, program code segments, drivers, firmware, microcodes, circuits, data, databases, data structures, tables, arrays and variables. The functions provided in components and "units" can be combined into fewer components and "units", or can be further divided into additional components and "units". In addition, components and "units" can be implemented as operating on one or more CPUs in equipment or secure multimedia cards.

[0046] When describing the present disclosure, if the relevant known functions or configurations are considered to make the main points of the present disclosure unnecessarily vague, their detailed description will be omitted. In addition, the terms to be described below have been defined by considering the functions in the present disclosure and may be different according to the intention or practice of the user, operator. Therefore, each term should be defined based on the content of the entire specification.

[0047] In addition, when describing the embodiments of the present disclosure in detail, the main target is a wireless communication system based on orthogonal frequency division multiplexing (OFDM), especially the Universal Terrestrial Radio Access (EUTRA) standard evolved by the Third Generation Partnership Project (3GPP), but the main points of the present disclosure can be slightly changed without greatly departing from the scope of the present disclosure, and can be applied to other communication systems with similar technical backgrounds and channel forms. This can be determined by a technician in the field to which the present disclosure belongs.

[0048] Meanwhile, research is being conducted on the coexistence of new 5G communication (or referred to as NR communication in the present disclosure) and existing LTE communication in the same spectrum in a mobile communication system.

[0049] The present disclosure relates to a wireless communication system, and more particularly, to a method and apparatus for transmitting and receiving data by a user equipment (UE) capable of transmitting and receiving data to and from each of at least one of different wireless communication systems coexisting on one carrier frequency or multiple carrier frequencies.

[0050] Generally, mobile communication systems are developed to provide voice services while ensuring the activities of users. However, the field of mobile communication systems has gradually expanded to data services in addition to voice, and has recently been developed to provide high-speed data services. However, more advanced mobile communication systems are needed because in current mobile communication systems that provide services, resources are insufficient and users need higher-speed services.

[0051] According to these requirements, the standard task of Long Term Evolution (LTE) in the 3rd Generation Partnership Project (3GPP) is in progress as a system in the next generation mobile communication system being developed. LTE is a technology for realizing a high-speed packet communication based on a maximum transfer rate of about 100Mbps. For this reason, several schemes have been discussed. For example, a scheme for reducing the number of nodes on the communication path by simplifying the structure of the network, a scheme for making the radio protocol as close as possible to the wireless channel, etc. are discussed.

[0052] The LTE system adopts a hybrid automatic repeat request (HARQ) method, and when a decoding failure occurs in the initial transmission, the corresponding data is retransmitted in the physical layer. According to the HARQ method, if the receiver does not accurately decode the data, the receiver sends information notifying the decoding failure (negative acknowledgment (NACK)) to the transmitter, so that the transmitter can retransmit the corresponding data in the physical layer. The receiver combines the data retransmitted by the transmitter with the existing data that failed to decode, thereby improving the data reception performance. In addition, according to the HARQ method, if the receiver has accurately decoded the data, the receiver sends information notifying the decoding success (acknowledgment (ACK)) to the transmitter, so that the transmitter can send new data.

[0053] Figure 1 is a diagram showing a basic structure of a time-frequency domain, which is a radio resource region in which downlink (DL) data or a control channel of an LTE system is transmitted, according to an embodiment of the present disclosure.

[0054] refer to Figure 1 , the horizontal axis indicates the time domain, and the vertical axis indicates the frequency domain. The minimum transmission unit in the time domain is an OFDM symbol. symb (102) OFDM symbols are grouped together to configure a time slot 106. Two time slots are grouped together to configure a subframe 105. The length of a time slot is 0.5 milliseconds (ms), and the length of a subframe is 1.0 milliseconds. In addition, a radio frame 114 is a time domain unit configured with 10 subframes. The minimum transmission unit in the frequency domain is a subcarrier. The bandwidth of the entire system transmission band is configured with a total of N BW There are 104 subcarriers.

[0055] In the time-frequency domain, the basic unit of resources is a resource element (RE) 112, and can be indicated as an OFDM symbol index and a subcarrier index. A resource block (RB) (or physical resource block (PRB)) 108 consists of N in the time domain. symb consecutive OFDM symbols 102 are defined, and in the frequency domain is defined as N RB Therefore, one RB 108 is configured with N consecutive subcarriers 110. symb x N RB 112 REs. Usually, the minimum data transmission unit is the RB unit. In the LTE system, generally speaking, N symb =7,N RB =12, and N BW and N RBProportional to the system transmission bandwidth. The data rate increases in proportion to the number of RBs scheduled in the user equipment (UE). The LTE system defines and operates 6 transmission bandwidths. In the case of an FDD system in which the downlink (DL) and uplink (UL) are divided into frequencies and operated, the DL transmission bandwidth and the UL transmission bandwidth may be different. The channel bandwidth indicates the radio frequency (RF) bandwidth corresponding to the system transmission bandwidth. Table 1 shows the correspondence between the system transmission bandwidth and the channel bandwidth defined in the LTE system. For example, in an LTE system with a 10MHz channel bandwidth, the transmission bandwidth is configured with 50 RBs.

[0056]

Table 1

[0057]

[0058] DL control information is sent in the first N OFDM symbols in a subframe. Generally speaking, N = {1, 2, 3}. Therefore, the value of N varies in each subframe according to the amount of control information that needs to be sent in the current subframe. The control information includes a control channel transmission interval indicator indicating how many OFDM symbols can be sent, scheduling information for DL ​​data or UL data, HARQ ACK / NACK signals, etc.

[0059] In the LTE system, scheduling information of DL data or UL data is sent from a base station (BS) to a UE through DL control information (DCI). Uplink (UL) refers to a wireless link through which a UE sends data or a control signal to a BS. Downlink (DL) refers to a wireless link through which a BS sends data or a control signal to a UE. Several formats are defined for DCI. A predetermined DCI format is applied and operated according to the following items: whether the DCI is scheduling information for UL data (UL grant) or scheduling information for DL ​​data (DL grant), whether the DCI is a compact DCI with small-size control information, whether the DCI applies spatial multiplexing using multiple antennas, or whether the DCI is a power-controlled DCI. For example, DCI format 1, i.e., scheduling control information for DL ​​data (DL grant), is configured to include at least the following control information.

[0060] - Resource allocation type 0 / 1 flag: It notifies whether the resource allocation method is type 0 or type 1. In type 0, resources are allocated in units of resource block groups (RBGs) by applying a bitmap method. In the LTE system, the basic unit for scheduling is a resource block (RB) represented as time domain and frequency domain resources. RBG is configured with multiple RBs and is a basic unit for scheduling in the type 0 method. In type 1, a specific RB is allocated within the RBG.

[0061] - Resource Block Assignment: It notifies the RBs assigned for data transmission. The indicated resources are determined depending on the system bandwidth and the resource allocation method.

[0062] - Modulation and Coding Scheme (MCS): It informs the modulation scheme used for data transmission and the size of the transport block, ie the data to be sent.

[0063] -HARQ process number: It notifies the HARQ process number.

[0064] - New Data Indicator: This informs whether the transmission is a HARQ initial transmission or a retransmission.

[0065] - Redundancy version: It informs the redundancy version of HARQ.

[0066] - Transmit Power Control (TPC) Command for Physical Uplink Control Channel (PUCCH): This notifies the TPC for PUCCH (ie, UL control channel).

[0067] The DCI is transmitted through a physical downlink control channel (PDCCH) or an enhanced PDCCH (EPDCCH), ie, a DL physical control channel, through a channel coding and modulation process.

[0068] Generally speaking, DCI is independently channel coded for each UE, configured as an independent PDCCH, and transmitted. In the time domain, the PDCCH is mapped and transmitted during the control channel transmission interval. The frequency domain mapping position of the PDCCH is determined by the UE's identifier (ID) and expanded to the entire system transmission bandwidth.

[0069] DL data is transmitted through the physical downlink shared channel (PDSCH), which is a physical channel used for DL ​​data transmission. PDSCH is transmitted after the control channel transmission interval. Scheduling information (such as detailed mapping position and modulation scheme in the frequency domain) is notified by DCI transmitted through PDCCH.

[0070] The BS notifies the UE of the modulation scheme applied to the PDSCH to be transmitted and the size of the data to be transmitted (transport block size (TBS)) by configuring a 5-bit MCS among the multiple control information configuring the DCI. The TBS corresponds to the size before channel coding for error correction is applied to the data to be transmitted by the BS (transport block (TB)).

[0071] The modulation schemes supported by the LTE system include quadrature phase shift keying (QPSK), 16-quadrature amplitude modulation (QAM) and 64QAM. m ) are 2, 4, and 6, respectively. That is, in the case of QPSK modulation, 2 bits can be transmitted per symbol, in the case of 16QAM modulation, 4 bits can be transmitted per symbol, and in the case of 64QAM modulation, 6 bits can be transmitted per symbol.

[0072] In 3GPP LTE Rel-10, in order to support a higher data transmission rate than LTE Rel-8, bandwidth extension technology is adopted. Compared with LTE Rel-8 UEs that send data in one frequency band through an extended frequency band, a technology called bandwidth extension or carrier aggregation (CA) can increase the data transmission rate to the same as the extended frequency band. Each frequency band is called a component carrier (CC). LTE Rel-8 UEs are defined as having one CC for each DL and UL. In addition, the DLCC and UL CC to which SIB-2 is connected are collectively referred to as cells. The SIB-2 connection relationship between the DL CC and the UL CC is sent through a system signal or a higher signal. UEs that support CA can receive DL data and send UL data through multiple serving cells.

[0073] In Rel-10, if the BS is in a situation where it is difficult for the BS to send a physical downlink control channel (PDCCH) to a specific UE in a specific service cell, the BS may send the PDCCH in another service cell, and may configure a carrier indicator field (CIF) in the UE as a field that notifies the UE that the corresponding PDCCH indicates the physical downlink shared channel (PDSCH) or physical uplink shared channel (PUSCH) of another service cell. CIP may be configured in UEs of CA. By adding 3 bits to the PDCCH information in a specific service cell, the CIF has been determined to indicate another service cell. The CIF is included only when the CIF is configured by a higher signal so that cross-carrier scheduling is performed. If the CIF is not configured by a higher signal so that cross-carrier scheduling is performed, or the CIF is configured by a higher signal so that self-scheduling is performed, the CIF is not included. In this case, cross-carrier scheduling is not performed. When the CIF is included in the DL assignment information, the CIF is defined as indicating the service cell to which the PDSCH scheduled by the DL assignment will be sent. When the CIF is included in the UL resource assignment information (UL Grant), the CIF is defined to indicate a serving cell to which a PUSCH scheduled by the UL Grant is to be transmitted.

[0074] As mentioned above, in LTE Rel-10, carrier aggregation (CA) (i.e., bandwidth extension technology) is defined, so that multiple service cells can be configured in the UE. In addition, the UE periodically or aperiodically sends channel information of multiple service cells to the BS for data scheduling of the BS. The BS schedules data for each carrier and sends data. The UE sends A / N feedback for the data sent by each carrier. LTE Rel-10 has been designed to send A / N feedback with a maximum of 21 bits. If the transmission of A / N feedback and the transmission of channel information overlap in one subframe, LTE Rel-10 has been designed to send A / N feedback and discard the channel information. LTE Rel-11 has been designed to multiplex the channel information of a cell with the A / N feedback, so that the A / N feedback with a maximum of 22 bits and the channel information of a cell are sent based on PUCCH format 3 in the transmission resources of PUCCH format 3.

[0075] In LTE Rel-13, a maximum of 32 service cell configuration scenarios are assumed. In addition to the licensed band, the concept of expanding the number of service cells to a maximum of 32 service cells using bands in unlicensed bands has been completed. In addition, by considering the limited number of licensed bands such as LTE frequencies, the provision of LTE services in unlicensed bands such as the 5GHz band has been completed. This is called licensed assisted access (LAA). LAA supports the operation of LTE cells (ie, licensed bands) as P cells and LAA cells (ie, unlicensed bands) as S cells by applying CA technology in LTE. Therefore, feedback that occurs in the LAA cell (ie, S cell) only needs to be sent in the P cell, as in LTE. The LAA cell can be freely applied by DL subframes and UL subframes. Unless otherwise described in this specification, LTE is described as including all advanced technologies of LTE, such as LTE-A and LAA.

[0076] In general, a TDD communication system uses a common frequency in DL and UL, but operates the transmission and reception of UL signals and DL signals differently in the time domain. In LTE TDD, UL signals and DL signals are divided and transmitted for each subframe. The subframes of UL / DL can be equally divided and operated in the time domain, more subframes can be assigned to DL and operated, or more subframes can be assigned to UL and operated according to the traffic load of UL and DL. In LTE, the length of a subframe is 1 millisecond, and 10 subframes are aggregated to configure one radio frame.

[0077]

Table 2

[0078]

[0079] Table 2 illustrates the TDD UL-DL configuration (or may also be referred to as TDD UL-DL configuration) defined in LTE. In Table 2, "D" indicates a subframe configured for DL ​​transmission. "U" indicates a subframe configured for UL transmission. "S" indicates a special subframe configured as a downlink pilot time slot (DwPTS), a guard period (GP), or an uplink pilot time slot (UpPTS). As in a common subframe, control information can be sent in the DwPTS in the DL. If the length of the DwPTS is long enough, DL data can also be sent according to the configuration state of the special subframe. The GP is an interval that accommodates the transition of the transmission state from DL to UL, and the length of the GP is determined based on the network configuration, etc. The UpPTS is used for the UE to send a sounding reference signal (SRS) required to estimate the UL channel state, and for the UE to send a random access channel (RACH) for random access.

[0080] For example, in the case of TDD UL-DL configuration #6, DL data and DL control information may be transmitted in subframes #0, #5, and #9, and UL data and UL control information may be transmitted in subframes #2, #3, #4, #7, and #8. In addition, DL control information and, in some cases, DL data may be transmitted in subframes #1 and #6 corresponding to special subframes, and SRS or RACH may be transmitted in UL.

[0081] In a TDD system, since DL or UL signal transmission is permitted only during specific time intervals, it is necessary to define a detailed timing relationship between UL / DL physical channels having a relationship with each other, such as a control channel for data scheduling, a scheduled data channel, and a HARQ ACK / NACK (or HARQ ACK) channel corresponding to the data channel.

[0082] First, in an LTE TDD system, the UL / DL timing relationship between a physical downlink shared channel (PDSCH, i.e., a physical channel for DL ​​data transmission) and a physical uplink control channel (PUCCH) or a physical uplink shared channel (PUSCH, i.e., a physical channel in which UL HARQ ACK / NACK corresponding to PDSCH is transmitted) is as follows.

[0083] When receiving the PDSCH transmitted from the BS in the subframe nk, the UE transmits UL HARQ ACK / NACK of the PDSCH in the UL subframe n. In this case, k is a constituent element of the set K, and K is defined in Table 3.

[0084]

Table 3

[0085]

[0086] According to the definition in Table 3, Table 4 lists in which subframe UL-HARQ ACK / NACK corresponding to PDSCH is transmitted again when PDSCH is transmitted in each DL subframe (D) or special subframe (S)n in each TDD UL-DL configuration.

[0087]

Table 4

[0088]

[0089]

[0090] Figure 2 is a diagram showing an operation example of a subframe in a TDD frame according to an embodiment of the present disclosure.

[0091] refer to Figure 2 Table 4 is described as follows. Figure 2 , Figure 2 4 is a diagram showing, based on the definition of Table 4, in which subframe UL HARQ ACK / NACK corresponding to PDSCH is transmitted when PDSCH is transmitted in each DL or special subframe in TDD UL-DL configuration #6 of Table 4.

[0092] For example, the UE transmits UL HARQ ACK / NACK (203) corresponding to PDSCH 201 transmitted by the BS in subframe #0 of radio frame i in subframe #7 of radio frame i. In this case, downlink control information (DCI) including scheduling information of PDSCH 201 is transmitted through PDCCH in the same subframe as the subframe in which the PDSCH is transmitted. As another example, the UE transmits UL HARQ ACK / NACK (207) corresponding to PDSCH 205 transmitted by the BS in subframe #9 of radio frame i in subframe #4 of radio frame i+1. Similarly, DCI including scheduling information of PDSCH 205 is transmitted through PDCCH in the same subframe as the subframe in which the PDSCH is transmitted.

[0093] In the LTE system, DL HARQ adopts an asynchronous HARQ method, and its data retransmission timing is not fixed. That is, if the BS receives NACK from the UE as feedback to the HARQ initial transmission data sent by the UE, the BS freely determines the transmission timing of the next HARQ retransmission data based on the scheduling operation. As a result of decoding the received data for the HARQ operation, the UE buffers the HARQ data determined to be erroneous, and then performs a combination with the next HARQ retransmission data. In this case, in order to keep the reception buffer capacity of the UE within a given limit, as shown in Table 5, a maximum number of DL HARQ processes is defined for each TDD UL-DL configuration. One HARQ process is mapped to one subframe in the time domain.

[0094]

Table 5

[0095]

[0096]

[0097] refer to Figure 2 , the UE decodes PDSCH 201 transmitted by the BS in subframe #0 of radio frame i, and if the result of decoding is determined to be an error, transmits NACK (203) in subframe #7 of radio frame i. When receiving NACK, the BS configures retransmission data for PDSCH 201 in PDSCH 209, and transmits PDSCH and PDCCH together. Figure 2 The example of FIG. 5 shows that the maximum number of DL HARQ processes of TDD UL-DL configuration #6 is 6, and retransmission data is sent in subframe #1 of radio frame i+1. That is, there are a total of 6 DL HARQ processes 211, 212, 213, 214, 215 and 216 between the initial transmission PDSCH 201 and the retransmission PDSCH 209.

[0098] In the LTE system, unlike DL HARQ, UL HARQ adopts a synchronous HARQ method, and its data transmission timing is fixed. That is, the UL / DL timing relationship between the physical uplink shared channel (PUSCH, i.e., a physical channel for UL data transmission) and the PDCCH (i.e., a DL control channel before the PUSCH) and the physical hybrid indicator channel (PHICH, i.e., a physical channel in which DL HARQ ACK / NACK corresponding to the PUSCH is transmitted) is fixed by the following rules.

[0099] When receiving a PDCCH including UL scheduling control information transmitted by the BS or a PHICH in which DL HARQ ACK / NACK is transmitted by the BS in subframe n from the BS, the UE transmits UL data corresponding to the control information through the PUSCH in subframe n+k. In this case, k is defined in Table 6.

[0100]

Table 6

[0101]

[0102]

[0103] In addition, when the UE receives a PHICH signal carrying DL HARQ ACK / NACK in subframe i from the BS, the PHICH signal corresponds to a PUSCH transmitted by the UE in subframe ik. In this case, k is defined in Table 7.

[0104]

Table 7

[0105]

[0106] Figure 3 is a diagram illustrating another operation example of a subframe in a TDD frame according to an embodiment of the present disclosure.

[0107] Specifically, Figure 3 6 is a diagram showing, based on the definitions of Table 6 and Table 7, when a PDCCH or a PHICH is transmitted in each DL or special subframe in TDD UL-DL configuration #1, respectively, in which subframe a UL PUSCH corresponding to the PDCCH or the PHICH is transmitted, and in which subframe a PHICH corresponding to the PUSCH is transmitted again.

[0108] refer to Figure 3 For example, the UE transmits a UL PUSCH corresponding to the PDCCH or PHICH 301 transmitted by the BS in subframe #1 of the radio frame i in subframe #7 of the radio frame i (303). In addition, the BS transmits a PHICH or PDCCH corresponding to the PUSCH to the UE in subframe #1 of the radio frame i+1 (305). As another example, the UE transmits a UL PUSCH corresponding to the PDCCH or PHICH 307 transmitted by the BS in subframe #6 of the radio frame i in subframe #2 of the radio frame i+1 (309). In addition, the BS transmits a PHICH or PDCCH corresponding to the PUSCH to the UE in subframe #6 of the radio frame i+1 (311).

[0109] In the LTE TDD system, the minimum transmission / reception processing time of the BS and UE is guaranteed by limiting the DL transmission of the PDCCH or PHICH corresponding to the PUSCH in a specific DL subframe related to the PUSCH transmission. Figure 3 In case of TDD UL-DL configuration #1, in subframes #0 and #5 in DL, a PDCCH corresponding to a PUSCH or a PHICH for scheduling a PUSCH is not transmitted.

[0110] At the same time, as a communication system after LTE, that is, a 5G wireless cellular communication system (hereinafter referred to as 5G or NR in this specification) can support services that meet various needs because it must freely combine the various needs of users and service providers.

[0111] Therefore, 5G can be defined as a technology used to meet the selected requirements for 5G services, such as UE maximum transmission rate 20Gbps, UE maximum speed 500km / h, maximum latency 0.5ms, UE access density 1,000,000UE / km 2 Among the requirements are various 5G-oriented services such as enhanced mobile broadband (eMBB) communication (hereinafter referred to as eMBB in this specification), massive machine type communication (mMTC) (hereinafter referred to as mMTC in this specification), and ultra-reliable and low-latency communication (URLLC) (hereinafter referred to as URLLC in this specification).

[0112] For example, in 5G, in order to provide eMBB, from the perspective of one BS, it is necessary to provide a UE maximum transmission rate of 20 Gbps in DL and a UE maximum transmission rate of 10 Gbps in UL. In addition, the average transmission rate that the UE may actually feel needs to be increased. In order to meet these requirements, it is necessary to improve transmission and reception technologies including further improved multiple-input multiple-output transmission technologies.

[0113] In addition, in order to support application services such as the Internet of Things (IoT) in 5G, mMTC is also considered. In order to efficiently provide IoT, mMTC requires requirements such as supporting access by many UEs in a cell, improving UE coverage, improving battery life, and reducing UE costs. IoT needs to support a large number of UEs in a cell (e.g., 1,000,000 UE / km 2), because IoT applies to multiple sensors and multiple devices and supports communication functions. In addition, mMTC is likely to have UEs located in shadow areas, such as basements of buildings or areas not covered by cells, due to the nature of its services, and therefore requires wider coverage than that provided by eMBB. mMTC is likely to be configured with cheap UEs and therefore require very long battery life, as it is difficult to frequently replace the UE's battery.

[0114] Finally, URLLC is a cellular-based wireless communication for a specific purpose and must provide ultra-low latency and ultra-reliable communications as a service for remote control of robots or machines, industrial automation, unmanned aerial equipment, remote health control, and emergency notification. For example, URLLC needs to meet a maximum latency of less than 0.5 milliseconds and also needs to provide 10 -5 Or lower packet error rate. Therefore, for URLLC, it is necessary to provide a smaller transmission time interval (TTI) than 5G services (such as eMBB). In addition, a design for allocating a wide range of resources in a frequency band is required.

[0115] The services considered in the aforementioned 5G wireless cellular communication system need to be provided as a framework. That is, for effective resource management and control, the services need to be integrated, controlled, and sent as a system rather than operating independently.

[0116] Figure 4 is a diagram showing an example of multiplexing and transmitting services considered in 5G in one system according to an embodiment of the present disclosure.

[0117] refer to Figure 4 , the frequency-time resources 401 used by 5G can be configured with a frequency axis 402 and a time axis 403. Figure 45G is shown to operate eMBB 405, mMTC 406, and URLLC 407 within one framework. In addition, in 5G, an enhanced mobile broadcast / multicast service (eMBMS) 408 for providing cellular-based broadcast services may be considered as a service that may be considered separately. Services considered in 5G, such as eMBB 405, mMTC 406, URLLC 407, and eMBMS 408, may be multiplexed and transmitted within a single system frequency bandwidth operated in 5G by time division multiplexing (TDM) or frequency division multiplexing (FDM). In addition, space division multiplexing may also be considered. In order to provide the aforementioned increased data transfer rate, eMBB 405 may occupy the largest frequency bandwidth and be transmitted at a specific given time. Therefore, the eMBB 405 service may be TDMed together with another service and transmitted within the system transmission bandwidth 401, and may be FDMed together with other services and transmitted within the system transmission bandwidth according to the necessity of other services.

[0118] Unlike other services, in order to ensure wide coverage, mMTC 406 requires an increased transmission interval, and the coverage can be ensured by repeatedly sending the same packet within the transmission interval. In addition, in order to reduce the complexity of the UE and the price of the UE, the transmission bandwidth that can be received by the UE is limited. When considering such requirements, mMTC 406 can be FDMed with other services and sent within the transmission system bandwidth 401 of 5G.

[0119] Compared to other services, URLLC 407 can have a short transmission time interval (TTI) to meet the ultra-delay requirements required for the service. In addition, URLLC 407 can have a wide bandwidth on the frequency side because it must have a low coding rate to meet the ultra-reliability requirements. When considering the requirements of URLLC 407, URLLC 407 can be TDMed with other services within the transmission system bandwidth 401 of 5G.

[0120] In order to meet the requirements of each service, each of the aforementioned services may have different transmission and reception schemes and different transmission and reception parameters. For example, each service may have a different parameter set (numerology) according to its service requirements. In this case, the parameter set includes a cyclic prefix (CP) length, a subcarrier spacing, a length of an OFDM symbol, a transmission time interval (TTI), etc., in a communication system based on orthogonal frequency division multiplexing (OFDM) or orthogonal frequency division multiple access (OFDMA). As an example in which a service has a different parameter set, eMBMS 408 may have a longer CP length than other services. eMBMS sends higher traffic based on broadcasting, and therefore the same data may be sent in all cells.

[0121] In this case, from the standpoint of the UE, when signals received from multiple cells arrive within the CP length, the UE can obtain a single frequency network (SFN) diversity gain because the UE can receive and decode all signals. Therefore, the advantage is that even UEs located at the cell boundary can receive broadcast information without coverage limitations. However, when supporting eMBMS in 5G, if the CP length is relatively longer than other services, eMBMS is wasted due to the CP overhead. In addition, a long OFDM symbol length is required compared to another service, which also requires a narrower subcarrier spacing than another service.

[0122] Furthermore, as an example of using different parameter sets between services in 5G, URLLC may require a shorter OFDM symbol length and also a wider subcarrier spacing because it requires a smaller TTI than another service.

[0123] Meanwhile, in 5G, one TTI can be defined as a time slot and can be configured as 14 OFDM symbols or 7 OFDM symbols. Therefore, in the case of a subcarrier spacing of 15KHz, a time slot has a length of 1 millisecond or 0.5 milliseconds. In addition, in 5G, for emergency transmission and transmission in unlicensed bands, one TTI can be defined as a mini-slot or sub-slot. The number of OFDM symbols that a mini-slot can have can be equal to starting from 1 to (the total number of OFDM symbols of the time slot - 1). If the length of a time slot corresponds to 14 OFDM symbols, the length of the mini-slot can be determined among 1 to 13 OFDM symbols. The length, format and repetition form of the time slot or mini-slot can be defined in the standard, or can be sent by a higher signal or system information or physical signal and received by the UE. In addition, instead of a mini-slot or sub-slot, the time slot can be determined among OFDM symbols 1 to 14. The length of the time slot can be sent by a higher signal or system information and received by the UE.

[0124] A time slot or a mini-time slot may be defined to have a variety of transmission formats and may be classified into the following formats.

[0125] - DL-only slot (or full DL slot): A DL-only slot includes only a DL interval and supports only DL transmission.

[0126] -DL center slot: The DL center slot includes a DL interval, a GP (or flexible symbol), and a UL interval. The number of OFDM symbols of the DL interval is greater than the number of OFDM symbols of the UL interval.

[0127] -UL center slot: The UL center slot includes a DL interval, a GP (or flexible symbol), and a UL interval. The number of OFDM symbols of the DL interval is smaller than the number of OFDM symbols of the UL interval.

[0128] - UL-only slot (or full UL slot): A UL-only slot includes only a UL interval and supports only UL transmission.

[0129] Only the slot format is classified, but the mini slot can also be classified according to the same classification method. That is, the mini slot format can be classified into DL only mini slot, DL center mini slot, UL center mini slot, UL only mini slot, etc. In the above description, the flexible symbol can be used as a guard symbol for transmission and reception switching, and can also be used for the purpose of channel estimation.

[0130] Hereinafter, when describing the embodiments of the present disclosure in detail, LTE and 5G systems will be the main targets, but the main points of the present disclosure may be slightly changed without greatly departing from the scope of the present disclosure, and may be applied to other communication systems with similar technical backgrounds and channel forms. This can be determined by those skilled in the art to which the present disclosure belongs.

[0131] In order to stably support the mobility of UEs in existing mobile communication systems while meeting the aforementioned requirements of 5G systems such as ultra-high-speed data services and ultra-low latency services, it is necessary to configure an integrated system by combining a beamforming technology operating in an ultra-high frequency band, a new radio access technology (new RAT) using a short TTI, and an LTE / LTE-A system operating in a relatively low frequency band. In this case, the function of the new radio access technology is to meet the requirements of the 5G system, while the function of the LTE / LTE-A system is to stably support the mobility of the UE.

[0132] Figure 5 is a diagram showing an example of a configuration of a communication system to which the present disclosure is applied, and is a diagram showing an example of a configuration of an integrated system according to an embodiment of the present disclosure, in which a BS responsible for a new wireless access technology and an LTE / LTE-A BS are combined.

[0133] refer to Figure 5 , small BSs 503, 505, and 507 with relatively small coverage areas 504, 506, and 508 may be deployed within the coverage area 502 of the macro BS 501. Generally, the macro BS 501 may transmit signals using relatively greater transmission power than each of the small BSs 503, 505, and 507, so the coverage area 502 of the macro BS 501 is relatively larger than the coverage areas 504, 506, and 508 of the small BSs 503, 505, and 507. As an example, in Figure 5In the example, the macro BS may indicate an LTE / LTE-A system operating in a relatively low frequency band, and each of the small BSs 503, 505, and 507 may indicate a system in which a new radio access technology (NR or 5G) operating in a relatively high frequency band has been applied.

[0134] The macro BS 501 and the small BSs 503, 505, and 507 are interconnected, and a backhaul delay may be given according to a connection state. Therefore, it may not be preferable to exchange information sensitive to transmission delay between the macro BS 501 and the small BSs 503, 505, and 507.

[0135] at the same time, Figure 5 The example of shows the carrier aggregation between the macro BS 501 and the small BSs 503, 505, and 507, but the present disclosure is not limited thereto and can be applied to the carrier aggregation between given BSs located at different geographical locations. For example, in some embodiments, the present disclosure can be applied to the carrier aggregation between macro BSs located at different locations and the carrier aggregation between small BSs located at different locations. In addition, the number of combined carriers is not limited. Optionally, the present disclosure can be applied to the carrier aggregation within the macro BS 501 and the carrier aggregation within each of the small BSs 503, 505, and 507.

[0136] refer to Figure 5 , the macro BS 501 may use frequency f1 for DL ​​signal transmission, and the small BSs 503, 505, and 507 may use frequency f2 for DL ​​signal transmission. In this case, the macro BS 501 may transmit data or control information to a given UE 509 through frequency f1, and the small BSs 503, 505, and 507 may transmit data or control information through frequency f2. Through the above-mentioned carrier aggregation, a BS adopting a new wireless access technology capable of supporting ultra-wideband in a high frequency band may provide an ultra-high-speed data service and an ultra-low-latency service, and a BS adopting an LTE / LTE-A technology in a relatively low frequency band may stably support the mobility of UEs together with the new wireless access technology.

[0137] At the same time, in addition to DL carrier aggregation, Figure 5The configuration shown can also be applied to UL carrier aggregation. For example, UE509 can send data or control information to macro BS 501 via frequency f1' used for UL signal transmission. In addition, UE 509 can send data or control information to small BSs 503, 505 and 507 via frequency f2' used for UL signal transmission. f1' can correspond to f1, and f2' can correspond to f2. The UL signal of the UE can be sent to the macro BS and the small BS at different timings, or can also be sent at the same time. In either case, due to the physical limitations of the UE's power amplifier device and the regulation of the radio waves of the UE's transmit power, the sum of the UE's UL transmit power at a given timing needs to be maintained within a given threshold.

[0138] In such Figure 5 In the illustrated environment, the operation of the UE (509) accessing the macro BS 501 and the small BSs 503, 505, and 507 and performing communication is called dual connectivity (DC). If the UE performs dual connectivity, the following two configuration schemes are possible.

[0139] In the first configuration scheme, after performing initial access to the macro BS 501 operating as an LTE / LTE-A system, the UE receives configuration information for transmitting and receiving data to and from the macro BS through a higher signal (system or RRC signal). Thereafter, the UE receives configuration information for data transmission and reception from the small BSs 503, 504, and 505 operating as an NR system through a higher signal (system or RRC signal) of the macro BS 501, and performs random access to the small BSs 503, 504, and 505, thereby becoming a dual-connection state in which the UE can transmit and receive data to and from the macro BS 501 and the small BSs 503, 504, and 505. In this case, the macro BS 501 operating as the LTE / LTE-A system is referred to as a primary cell group (MCG), and the small BSs 503, 504, and 505 operating as an NR system are referred to as a secondary cell group (SCG). When the UE is in a dual-connection state based on the first configuration scheme, it may indicate that the UE has been configured with an MCG using E-UTRA radio access (or LTE / LTE-A) and an SCG using NR radio access. Optionally, it may indicate that the UE has been configured with E-UTRA NR dual connectivity (EN-DC).

[0140] In the second configuration scheme, after performing initial access to the small BSs 503, 504, and 505 operating as the NR system, the UE receives configuration information for sending and receiving data to and from the small BSs through a higher signal (system or RRC signal). Thereafter, the UE receives configuration information for data transmission and reception from the macro BS 501 operating as the LTE / LTE-A system through the higher signal (system or RRC signal) of the small BSs 503, 504, and 505, and performs random access to the macro BS 501, thereby becoming a dual connection state in which the UE can send and receive data to and from the small BSs 503, 504, and 505 and the macro BS 501. In this case, the small BSs 503, 504, and 505 operating as the NR system are referred to as MCGs, and the macro BS 501 operating as the LTE system is referred to as SCGs. When the UE is in a dual connection state based on the second configuration scheme, it can be indicated that the UE has been configured with an MCG using NR wireless access and an SCG using E-UTRA wireless access (or LTE / LTE-A). Optionally, it may indicate that the UE has been configured with NR E-UTRA Dual Connectivity (NE-DC).

[0141] In the following, the embodiments described in the present disclosure are proposed by considering the first dual connection configuration scheme and the second dual connection configuration scheme. That is, according to whether the LTE cell using E-UTRA corresponds to the MCG or the NR cell using NR is the MCG, the present disclosure proposes another embodiment. According to whether the LTE cell using E-UTRA corresponds to the MCG or the NR cell using NR is the MCG, another embodiment is proposed, because when the UE is in a dual connection state, importance needs to be assigned to the UL transmission to the MCG rather than the UL transmission to the SCG. In addition, through higher signal configuration and indications in the PDCCH, the timing of UL transmission to the cell using NR (for example, PDCCH to PUSCH transmission timing or PDCCH to PUCCH transmission timing) can be indicated differently. The timing of UL transmission to the cell using LTE (for example, PDCCH to PUSCH transmission timing or PDCCH to PUCCH transmission timing) is fixed. Therefore, the embodiments of the present disclosure are proposed by considering these conditions.

[0142] <Scheme for UE to perform UL transmission according to whether UE has dynamic power sharing capability when LTE TDD is the primary cell and NR is the secondary cell>

[0143] Through the following description and Figure 6 , 7, 8, 9 and 10 describe various embodiments of a scheme in which, if the UE is configured with E-UTRA NR dual connectivity (EN-DC) in which LTE TDD is a primary cell and NR is a secondary cell, a UE performs UL transmission according to whether the UE has dynamic power sharing capability.

[0144] If the UE is configured with EN-DC, that is, if the UE is configured with an MCG using E-UTRA radio access and an SCG using NR radio access, the UE may receive a configuration of a maximum power value for the UL of LTE and a maximum power value for the UL of NR from an LTE BS or an NR BS. In addition, the UE may receive a configuration of a maximum power value for EN-DC operation from an LTE BS or an NR BS. In this case, when the sum of the maximum power value for the UL of LTE and the maximum power value for the UL of NR is greater than the maximum power value for EN-DC operation, the UE may apply one of the following two power sharing methods.

[0145] The first method is semi-static power sharing between MCG (LTE) and SCG (NR).

[0146] When the UE receives a reference TDD configuration that limits LTE UL transmission only in a specific subframe used for LTE UL transmission, if the UE does not indicate or report the dynamic power sharing capability to the BS, the UE does not expect to perform UL transmission in the NR time slot that matches such a time interval: LTE is a UL subframe based on the reference TDD configuration in this time interval (or does not expect the configuration or scheduling indicating NR UL transmission from the NR BS). In addition to the reference TDD configuration, all subframes configured to perform LTE UL transmission can be moved by HARQ offset by adding HARQ offset. If the subframe in which LTE UL transmission is performed based on the reference TDD configuration is #2, when the HARQ offset configured in the UE is 1, the UE can determine the subframe in which LTE UL transmission is performed as subframe #3 by adding HARQ offset 1 to #2 (i.e., subframe index). The UE can receive the HARQ offset through a higher signal. Thereafter, although not described separately in the present disclosure, the HARQ offset can be applied to the reference TDD configuration described in the present disclosure in the same manner as above.

[0147] The second method is dynamic power sharing between MCG (LTE) and SCG (NR).

[0148] If the UE indicates or reports the dynamic power sharing capability to the BS, when the UE's LTE UL transmission and the NR UL transmission conflict with each other and the sum of the power used for the LTE UL transmission and the power used for the NR UL transmission is greater than the maximum power value for EN-DC operation, the UE can discard the NR UL transmission as a first solution. Optionally, as a second solution, the UE can reduce the NR UL transmission power so that the sum of the power used for the LTE UL transmission and the power used for the NR UL transmission is less than the maximum power value for EN-DC operation. When the NR UL transmission power is reduced, if the transmission power to be reduced is greater than X, the UE can discard the NR transmission. When the transmission power to be reduced is less than X, the UE can perform NR UL transmission using the reduced transmission power.

[0149] In the first or second method, the UE may report to the BS the capability of not supporting simultaneous UL transmission through a higher signal. Optionally, the UE may report the capability of not supporting simultaneous UL transmission for a specific frequency band combination including an LTE TDD cell or carrier and an NR cell or carrier through a higher signal.

[0150] Figure 6 is a diagram showing a first problem situation to be solved according to an embodiment of the present disclosure.

[0151] refer to Figure 6 , LTE 601 is an MCG and operates as TDD, and NR 602 is an SCG. Therefore, the first problem case can be applied to the case where the UE is configured with EN-DC. Figure 6 In the example, the TDD cell of LTE 601 is TDD UL-DL configuration #6 (for example, this describes the case of TDD UL-DL configuration #6, but the present disclosure is not limited thereto). By receiving TDD UL-DL configuration #6 from the system information, the EN-DC UE can know the positions of UL subframes, special subframes, and DL subframes. The EN-DC UE can receive information about the UL or DL ​​of NR 602, or information about the positions or numbers of flexible time slots and OFDM symbols through system information, higher information, or a physical layer signal.

[0152] refer to Figure 6, the problem situation is described by considering a case where the EN-DC UE operates to perform semi-static power sharing between LTE 601 and NR 602. That is, a case is assumed in which the EN-DC UE receives a configuration of reference TDD configuration #5 among reference TDD configurations #2, #4, and #5 that can limit LTE UL transmission only in a specific subframe of LTE UL transmission, and does not indicate or report dynamic power sharing capability to the LTE or NR BS. In this case, the EN-DC UE can know that it can perform LTE UL transmission (604 and 607) only in UL subframe #2 that matches the UL subframe based on reference TDD configuration #5 among UL subframes #2, #3, #4, #7, and #8 of TDD UL-DL configuration #6 of LTE 601 received from system information, and can perform NR UL transmission in a time slot of NR that matches the time interval of the remaining UL subframes #3, #4, #7, and #8.

[0153] If, from the system information of LTE 601 regarding UL data transmission, the EN-DC UE follows the UL HARQ timing relationship between PDCCH transmission and PUSCH transmission defined in a given TDD UL-DL configuration #6 (refer to Tables 6 and 7), the EN-DC UE performs PUSCH transmission (611) in UL subframe #2 based on the scheduling of the PDCCH received from the LTE BS in the DL subframe #5 of LTE 601, receives ACK / NACK (612) of PUSCH or PDCCH from the LTE BS in the special subframe #6, and sends the corresponding retransmission PUSCH (613) in UL subframe #3. The time interval corresponding to UL subframe #3 is an interval in which only NR UL transmission is possible. Therefore, there is a problem that if the PUSCH retransmission of the above-mentioned EN-DC UE occurs, the NR UL transmission and the LTE UL transmission conflict with each other. Therefore, the present disclosure provides a solution for solving the above-mentioned problem through embodiments 1 and 2.

[0154] refer to Figure 6 , the problem situation is described by considering a situation in which the EN-DC UE operates to perform dynamic power sharing between LTE 601 and NR 602. That is, if the EN-DC UE indicates or reports the dynamic power sharing capability to the BS, the present disclosure provides a solution to the problem by the EN-DC UE through Embodiment 3: If, in a time interval of UL subframe #2 on which a restriction has been imposed so that LTE UL transmission is performed based on a reference TDD configuration, the UE's LTE UL transmission and the NR UL transmission are performed as follows: Figure 6604, or the sum of the power for LTE UL transmission and the power for NR UL transmission is greater than the maximum power value for EN-DC operation. In addition, the present disclosure provides a solution to the problem by the EN-DC UE through embodiment 4: if the UE's LTE UL transmission and the NR UL transmission are in UL subframes #3, #4, #7, and #8 (i.e., time intervals other than UL subframe #2 to which restrictions have been imposed so that LTE UL transmission is performed based on the reference TDD configuration) as Figure 6 608 conflict with each other, or the sum of the power used for LTE UL transmission and the power used for NR UL transmission is greater than the maximum power value for EN-DC operation.

[0155] Example 1

[0156] Figure 7 is a diagram showing UL transmission according to Embodiment 1 of the present disclosure.

[0157] refer to Figure 7 , LTE 701 is MCG and operates as TDD, and NR 702 is SCG. Therefore, Embodiment 1 may be applied to the case where the UE is configured with EN-DC. Figure 7 In the example, the TDD cell of LTE 701 is TDD UL-DL configuration #1, and the EN-DC UE can know the positions of the UL subframe, the special subframe, and the DL subframe by receiving TDD UL-DL configuration #1 from the system information. Figure 7 The TDD UL-DL configuration #1 shown in FIG. 1 is only an example and does not limit the present disclosure. The EN-DC UE may receive information about the UL or DL ​​of the NR 702, or information about the position or number of the flexible time slot and the OFDM symbol through system information, higher information, or a physical layer signal. Figure 7In the embodiment, a case where the EN-DC UE operates to perform semi-static power sharing between LTE 701 and NR 702 is considered. That is, a case is assumed in which the EN-DC UE receives a configuration of reference TDD configuration #2 among reference TDD configurations #2, #4, and #5 that can limit LTE UL transmission only in a specific subframe for LTE UL transmission, and does not indicate or report dynamic power sharing capability to the LTE or NR BS. In this case, the EN-DC UE can know that it can perform LTE UL transmission only in UL subframes #2, #7 that match the UL subframe based on reference TDD configuration #2 among UL subframes #2, #3, #7, and #8 of TDD UL-DL configuration #1 of LTE 701 received from system information, and can perform NR UL transmission in the time slot of NR that matches the time interval of the remaining UL subframes #3 and #8 (refer to Tables 3 and 4).

[0158] As described above, assuming that the TDD UL-DL configuration received from the LTE BS of LTE 701 is one of #1, #2, #3, #4, and #5 except #0 and #6, and the reference TDD configuration received from the LTE BS or NR BS by a higher signal is one of #2, #4, and #5, if for UL data transmission, the EN-DC UE follows the TDD UL-DL configuration given by the system information of LTE 701 ( Figure 7 According to the UL HARQ timing relationship between PDCCH transmission and PUSCH transmission defined in TDD UL-DL configuration #1 in EN-DC UE (refer to Tables 6 and 7), in the case of EN-DC UE, the UL subframes based on PDCCH reception, PUSCH transmission and PUSCH retransmission occur in the same LTE UL subframe of each radio frame (711, 712, 713, 714). Therefore, when the PUSCH retransmission of the above EN-DC UE occurs, the problem of NR UL transmission and LTE UL transmission conflicting with each other does not occur.

[0159] Example 2

[0160] Figure 8 is a diagram showing UL transmission according to Embodiment 2 of the present disclosure.

[0161] refer to Figure 8 , LTE 801 is MCG and operates as TDD, and NR 802 is SCG. Therefore, Embodiment 2 may be applied to the case where the UE is configured with EN-DC. Figure 8In the example, the TDD cell of LTE 801 is TDD UL-DL configuration #6, and the EN-DC UE can know the positions of the UL subframe, the special subframe, and the DL subframe by receiving TDD UL-DL configuration #6 from the system information. Figure 8 The TDD UL-DL configuration #6 shown in FIG. 6 is only an example and does not limit the present disclosure. The EN-DC UE may receive information about the UL or UL of NR 802, or information about the position or number of flexible time slots and OFDM symbols through system information, higher information, or a physical layer signal. Figure 8 In the embodiment of the present invention, a case where the EN-DC UE operates to perform semi-static power sharing between LTE 801 and NR 802 is considered. That is, a case is assumed in which the EN-DC UE receives a configuration of reference TDD configuration #4 among reference TDD configurations #2, #4, and #5 that is capable of limiting LTE UL transmission only in a specific subframe for LTE UL transmission, and does not indicate or report dynamic power sharing capability to the LTE or NR BS. In this case, the EN-DC UE can know that it can perform LTE UL transmission only in UL subframes #2 and #3 that match the UL subframe based on reference TDD configuration #4 among UL subframes #2, #3, #4, #7, and #8 of TDD UL-DL configuration #6 of LTE 801 received from the system information, and can perform NR UL transmission in the time slot of NR that matches the time interval of the remaining UL subframes #4, #7, and #8 (refer to Tables 3 and 4).

[0162] As described above, if the TDD UL-DL configuration received from the LTE BS of LTE 801 is one of #0 and #6, and the reference TDD configuration received from the LTE BS or NR BS through a higher signal is one of #2, #4 and #5, the present disclosure proposes that the EN-DC UE follows the UL HARQ timing relationship between PDCCH transmission and PUSCH transmission defined based on another specific second reference TDD configuration, rather than the TDD UL-DL configuration for UL data transmission given by the system information of LTE 801 (refer to Tables 6 and 7). In this case, in the case of the EN-DC UE, the UL subframes based on PDCCH reception, PUSCH transmission and PUSCH retransmission occur in the same LTE UL subframe of each radio frame (811, 812, 813 and 814). Therefore, when the PUSCH retransmission of the above-mentioned EN-DC UE occurs, the problem of NR UL transmission and LTE UL transmission conflicting with each other does not occur.

[0163] A second reference TDD configuration for defining a UL-HARQ timing relationship may be defined such that UL subframes for PDCCH reception, PUSCH transmission, and PUSCH retransmission based on EN-DC UEs occur in the same LTE UL subframe in each radio frame, and may be defined using, for example, the following method.

[0164] If the TDD UL-DL configuration of the system information received from the LTE BS is #6, and the reference TDD configuration is one of #2, #4, and #5, the second reference TDD configuration for UL HARQ timing may be determined as #1.

[0165] If the TDD UL-DL configuration of the system information received from the LTE BS is #0, and the reference TDD configuration is one of #2 and #5, the second reference TDD configuration for UL HARQ timing may be determined as #1.

[0166] If the TDD UL-DL configuration of the system information received from the LTE BS is #0, the reference TDD configuration is #4, and the second reference TDD configuration #1 for UL HARQ timing is followed, the PDCCH for scheduling the PUSCH of UL subframe #3 needs to be transmitted in DL subframe #9 of the previous radio frame. However, there is a problem: because in UL-DL configuration #0, subframe #9 is UL, the PDCCH cannot be transmitted.

[0167] Therefore, if the TDD UL-DL configuration of the system information received from the LTE BS is #0, and the reference TDD configuration is #4, the following suggestions are possible.

[0168] First, the second reference TDD configuration for UL HARQ timing is #1, but the EN-DC UE may not expect scheduling of PUSCH in UL subframe #3 of LTE.

[0169] Second, the second reference TDD configuration for UL HARQ timing in UL subframe #2 is #1, but the EN-DC UE may expect that the PDCCH for scheduling the PUSCH in UL subframe #3 is transmitted in DL subframe #5 of the previous radio frame.

[0170] Third, if the TDD UL-DL configuration of the system information received from the LTE BS is #0, the EN-DC UE may not expect to refer to TDD configuration #4. That is, the UE may expect only the case where the reference TDD configuration is configured as #2 or #5.

[0171] Unlike the proposal, from the beginning, the EN-DC UE may not expect the UL-DL configuration from the system information to be #0 or #6. That is, the EN-DC UE does not expect a configuration such as Embodiment 2 and may receive only one of TDD UL-DL configurations #1, #2, #3, #4, and #5 from the system information, and may receive one of the reference TDD configurations #2, #4, and #5 from a higher signal. The second reference TDD configuration for UL HARQ timing is defined as #1.

[0172] Example 3

[0173] refer to Figure 6 , if the EN-DC UE operates to perform dynamic power sharing between LTE 601 and NR 602, that is, if the EN-DC UE indicates or reports the dynamic power sharing capability to the BS, the present disclosure proposes a solution to the problem by the EN-DC UE through Embodiment 3: if the UE's LTE UL transmission and the NR UL transmission are in the time interval of UL subframe #2 on which a restriction has been imposed so that the LTE UL transmission is performed based on the reference TDD configuration, as shown in FIG. Figure 6 As shown in 604, they conflict with each other, or the sum of the power used for LTE UL transmission and the power used for NR UL transmission is greater than the maximum power value for EN-DC operation.

[0174] According to the first scheme, the EN-DC UE only performs LTE UL transmission and always discards NR UL transmission. Since the above scheme can be used to protect the LTE UL transmission that plays the role of MCG, the connection with the MCG can be maintained, and important information required for RRC connection can be sent to and received from the MCG.

[0175] According to the second scheme, the EN-DC UE maintains the power of LTE UL transmission and reduces the power for NR UL transmission so that the sum of the power for LTE UL transmission and the power for NR UL transmission is equal to or less than the set maximum power value for EN-DC operation. Since the above scheme can be used to protect the LTE UL transmission that plays the role of MCG, the connection with the MCG can be maintained, and important information required for RRC connection can be sent to and received from the MCG. In addition, NR UL transmission can be performed within the EN-DC maximum power.

[0176] Example 4

[0177] refer to Figure 6, if the EN-DC UE operates to perform dynamic power sharing between LTE 601 and NR 602, that is, if the EN-DC UE indicates or reports the dynamic power sharing capability to the BS, the present disclosure proposes a solution to the problem by the EN-DC UE through Embodiment 4: if the UE's LTE UL transmission and the NR UL transmission are in UL subframes #3, #4, #7, and #8 (that is, time intervals other than UL subframe #2 on which a restriction has been imposed so that the LTE UL transmission is performed based on the reference TDD configuration) as Figure 6 608 conflict with each other, or the sum of the power used for LTE UL transmission and the power used for NR UL transmission is greater than the maximum power value for EN-DC operation.

[0178] According to the first scheme, the EN-DC UE performs only LTE UL transmission but always discards NR UL transmission. Through the above scheme, LTE UL transmission that functions as the MCG can be protected even in UL subframes corresponding to time intervals other than UL subframe #2 to which restrictions have been imposed so that LTE UL transmission is performed based on the reference TDD configuration. Therefore, the connection with the MCG can be maintained, and important information required for the RRC connection can be sent and received from the MCG.

[0179] According to the second scheme, the EN-DC UE maintains the power of LTE UL transmission and reduces the power of NR UL transmission so that the sum of the power used for LTE UL transmission and the power used for NR UL transmission is equal to or less than the set maximum power value for EN-DC operation. Through the above scheme, the LTE UL transmission that plays the role of MCG is protected even in UL subframes corresponding to time intervals other than UL subframe #2 on which restrictions have been imposed so that LTE UL transmission is performed based on the reference TDD configuration. Therefore, the connection with the MCG can be maintained, and important information required for the RRC connection can be sent to and received from the MCG. In addition, because NR UL transmission can be performed within the EN-DC maximum power, the transmission and reception data throughput of the UE can be improved.

[0180] According to the third scheme, the EN-DC UE performs only NR UL transmission and always discards LTE UL transmission. Through the above scheme, in the UL subframe corresponding to the time interval other than the UL subframe #2 to which the restriction has been imposed so that the LTE UL transmission is performed based on the reference TDD configuration, NR UL transmission that plays the role of SCG instead of LTE UL transmission that plays the role of MCG becomes possible. Therefore, the amount of data transmission and reception using NR can be increased, and thus the UL / DL data throughput of the EN-DC UE can be increased.

[0181] As another scheme, the above three schemes can be mixed and applied to EN-DC UE. The first scheme can be applied to a specific LTE UL channel transmission signal or a specific LTE UL transmission signal, such as a case where the LTE UL transmission is an important UL transmission for the RRC connection, such as a physical random access channel (PRACH) transmission. If the LTE UL transmission does not correspond to a specific LTE UL channel transmission signal or a specific LTE UL transmission signal, the second scheme or the third scheme can be applied. Optionally, the third scheme can be applied to a specific NR UL channel transmission signal or a specific NR UL transmission signal, such as a case where the NR UL transmission is an important UL transmission such as a PRACH transmission. If the LTE UL transmission does not correspond to a specific NR UL channel transmission signal or a specific NR UL transmission signal, the first scheme or the second scheme can be applied.

[0182] Fig. 9A is a diagram illustrating a BS operation according to an embodiment of the present disclosure.

[0183] refer to Fig. 9A , at operation 911, the BS sends configuration information of each cell to the UE through system information or a higher signal. The configuration information may be cell-related information (e.g., TDD or FDD information, UL / DL carrier frequency, UL / DL frequency band, and at least one of UL / DL subcarrier spacing) of an MCG or SCG cell, which is necessary for dual connectivity, or may be configuration information necessary for data transmission and reception in an MCG or SCG. Optionally, the configuration information may include at least one of the configuration information related to the various parameters described in the embodiments of the present disclosure. The BS may be an NR BS using NR wireless access, and may be an E-UTRA BS using E-UTRA wireless access.

[0184] At operation 912, according to an embodiment proposed in the present disclosure, the BS configures UL transmission in the UE and sends scheduling information indicating the UL transmission. The BS may be an NR BS using NR radio access, and may be an E-UTRA BS using E-UTRA radio access. The UL transmission configuration may mean a UL transmission that is not indicated by the PDCCH like periodic channel information transmission, but is configured by a higher signal configuration. The UL transmission indicated by the scheduling information may mean a UL transmission indicated by the PDCCH and performed by the UE, like a PUSCH transmission or a HARQ-ACK transmission, or may be a UL transmission from the UE, such as a PRACH or an SRS.

[0185] At operation 913, according to an embodiment proposed in the present disclosure, the BS receives UL transmission from the UE. The BS may be an NR BS using NR radio access, and may be an E-UTRA BS using E-UTRA radio access.

[0186] Fig. 9B is a diagram illustrating UE operation according to an embodiment of the present disclosure.

[0187] refer to Fig. 9B , at operation 921, the UE receives configuration information of each cell from the BS through system information or a higher signal. The configuration information may be cell-related information (e.g., TDD or FDD information, UL / DL carrier frequency, UL / DL frequency band, and at least one of UL / DL subcarrier spacing) of an MCG or SCG cell, which is necessary for dual connectivity, or may be configuration information necessary for data transmission and reception in an MCG or SCG. Optionally, the configuration information may include at least one of the configuration information related to the various parameters described in the embodiments of the present disclosure. As described in the embodiments of the present disclosure, before the UE receives the dynamic power sharing capability from the BS through a higher signal, the UE may send capability-related information to the BS. The BS may be an NR BS using NR wireless access, and may be an E-UTRA BS using E-UTRA wireless access.

[0188] At operation 922, according to an embodiment proposed in the present disclosure, the UE receives UL transmission configuration information from the BS, and receives scheduling information indicating UL transmission. The BS may be an NR BS using NR radio access, and may be an E-UTRA BS using E-UTRA radio access. The UL transmission configuration information may mean configuration information related to UL transmission, which is not indicated by PDCCH like periodic channel information transmission, but is configured by a higher signal configuration. The UL transmission indicated by the scheduling information may mean UL transmission indicated by PDCCH like PUSCH transmission or HARQ-ACK transmission and sent by the UE, or may be UL transmission from the UE, such as PRACH or SRS.

[0189] At operation 923, according to an embodiment proposed in the present disclosure, the UE transmits UL transmission to the BS by controlling transmission timing and transmission power based on a UL-HARQ timing relationship (PDCCH to PUSCH transmission, PUSCH to PDCCH transmission, etc.). As described in the embodiments of the present disclosure, controlling the transmission power may include an operation of dropping UL transmission or reducing UL transmission power. The BS may be an NR BS using NR radio access, and may be an E-UTRA BS using E-UTRA radio access.

[0190] Fig.10is a diagram showing a second problem to be solved according to an embodiment of the present disclosure. Assume a situation in which Fig.10 The configured cell, as referenced Figure 5 As described, the EN-DC UE performs data transmission and reception to and from the BS.

[0191] refer to Fig.10 , assuming a case where LTE is MCG and is configured as carrier aggregation (CA) in EN-DC UE through 2 cells, and NR is SCG and is configured in EN-DC UE through one cell 1002. Assuming a case where a primary cell (Pcell) 1001 as a first LTE cell of MCG is a TDD cell following TDD UL-DL configuration #0, and a secondary cell (Scell) 1003 as a second LTE cell of MCG operates as an FDD cell. Reference Fig.10 , Scell ​​1003 is an FDD cell, but can be operated as a TDD cell, in particular as a TDD UL-DL configuration #0, such as the configuration of Pcell 1001. The present disclosure can be applied to a case where Scell ​​1003 is a TDD cell operating as another TDD UL-DL configuration. That is, the TDD configuration or FDD configuration of Scell ​​1003 is not limited to Fig.10 The configuration shown is for reference only and may be identically applied to other configurations.

[0192] refer to Fig.10 , by receiving TDD UL-DL configuration #0 of Pcell 1001 through system information, EN-DC UE can know the positions of UL subframes, special subframes, and DL subframes, and by receiving carrier information and bandwidth information through a higher signal, can know the carrier information and bandwidth information of Scell ​​1003. EN-DC UE can receive information about UL or DL ​​of NR cell 1002, or information about the position or number of flexible time slots and OFDM symbols through system information, higher information, or a physical layer signal. Fig.10, a case where the EN-DC UE operates to perform semi-static power sharing between LTE and NR is considered. That is, a case is assumed in which the EN-DC UE receives a configuration of reference TDD configuration #2 among reference TDD configurations #2, #4, and #5 that can limit LTE UL transmission only in a specific subframe of LTE UL transmission by a higher signal, or the EN-DC UE does not indicate or report dynamic power sharing capability to the LTE or NR BS. In this case, the EN-DC UE can know that it can only perform LTE UL transmission in UL subframes #2, #7 that match the UL subframe based on reference TDD configuration #2 among UL subframes #2, #3, #4, #7, and #8, #9 of TDD UL-DL configuration #0 of LTE Pcell 1001 received through system information, and can perform NR UL transmission in the time slot of NR that matches the time interval of the remaining UL subframes #3, #4, #8, and #9. Therefore, based on the timing relationship in UL-DL configuration #2 corresponding to #2 of Tables 3 and 4 (i.e., reference TDD configuration value), the EN-DC UE sends HARQ ACK / NACK for DL ​​data sent in the LTE Pcell 1001. That is, if DL data is received in subframe #4, #5, #8, or #6 of the LTE Pcell 1001, the EN-DC UE sends HARQ ACK / NACK feedback for DL ​​data in subframe #2 of the LTE Pcell 1001 (1011). If DL data is received in subframe #9, #0, #3, or #1, the EN-DC UE sends HARQ ACK / NACK feedback for DL ​​data in subframe #7 of the LTE Pcell 1001 (1012).

[0193] Since HARQ ACK / NACK for DL ​​data reception of LTE Scell ​​1003 is also transmitted in Pcell 1001 (i.e., primary cell), HARQ ACK / NACK can be transmitted only in a specific LTE subframe of Pcell 1001. That is, it can be seen that LTE UL transmission can be performed only in UL subframes #2 and #7 matching the UL subframes based on reference TDD configuration #2, and only NR UL transmission can be performed in the time slots of NR matching the time intervals of the remaining UL subframes #3, #4, #8, and #9.

[0194] Therefore, based on the timing relationship in the DL reference UL-DL configuration #2 (i.e., reference TDD configuration value) corresponding to #2 of Table 8, the EN-DC UE sends HARQ ACK / NACK for DL ​​data sent by the LTE Scell ​​1003. That is, when DL data is received in subframes #4, #5, #6, #7, and #8 of the LTE Scell ​​1003, the EN-DC UE sends HARQ ACK / NACK feedback for DL ​​data in subframe #2 of the Pcell 1001 (1013). When DL data is received in subframes #9, #0, #1, #2, and #3 of the LTE Scell ​​1003, the EN-DC UE sends HARQ ACK / NACK feedback for DL ​​data in subframe #7 of the Pcell 1001 (1014).

[0195] When receiving a PDSCH transmitted in a subframe nk of an FDD Scell ​​from a BS, a UE transmits a UL HARQ ACK / NACK for the PDSCH in a UL subframe n of a TDD Pcell. In this case, k is a constituent element of a set K, and K may be defined similarly to Table 8 of Table 3.

[0196]

Table 8

[0197]

[0198] In this case, when sending HARQ ACK / NACK feedback in subframe #2 of Pcell 1001, EN-DC UE sends HARQ ACK / NACK feedback using PUCCH format 3 or format 4 or format 5 defined in the LTE standard. Which PUCCH format to use and how to send HARQ ACK / NACK feedback are pre-configured in EN-DC UE by the base station through a higher signal. The higher signal may include information about the PUCCH format to be used when the EN-DC UE sends HARQ-ACK feedback and a plurality of resources for sending the PUCCH format.

[0199] A method for selecting a resource from a plurality of resources for transmitting a PUCCH format by an EN-DC UE is as follows. If a "DL Assignment Index (DAI)" field included in a received PDCCH / EPDCCH is greater than 1 or the "DAI" field is 1, but the PDCCH / EPDCCH in which the "DAI" field is 1 is not the first PDCCH / EPDCCH in K (Table 3 or Table 8), the EN-DC UE that has received a plurality of PDCCH / EPDCCHs through a plurality of subframes of an LTE Pcell 1001 or an LTE Scell ​​1003 may use a 2-bit value of a "Transmit Power Control (TPC) Command" field of the PDCCH / EPDCCH to indicate one of the four resources. A UE that indicates a resource through the "TPC Command" field transmits HARQ ACK / NACK feedback in a PUCCH format configured using the resource. In this case, if the 'DAI' field is 1 or the PDCCH / EPDCCH in which the 'DAI' field is 1 is the first PDCCH / EPDCCH in K (Table 3 or Table 8), the 2-bit value of the 'TPC Command' field of the PDCCH / EPDCCH may indicate the power control value when the configured PUCCH format is transmitted. The EN-DC UE may control and transmit the power of the PUCCH format based on the 'TPC Command' field.

[0200] In this case, if the EN-DC UE receives only PDSCH through a first PDCCH / EPDCCH in LTE Pcell 1001, or receives only one PDCCH / EPDCCH (1011 or 1012) for DL ​​SPS release, or receives only one PDSCH without a corresponding PDCCH, or the BS has sent a PDCCH / EPDCCH for scheduling multiple PDSCHs in multiple subframes, but the EN-DC UE receives only one PDSCH through a first PDCCH / EPDCCH due to a reception error, there is a problem that when the PUCCH format is transmitted, the EN-DC UE cannot know whether the "TPC command" field within the received PDCCH / EPDCCH is a field for power control, and which one of the multiple configured PUCCH transmission resources it must use to transmit the PUCCH format. Therefore, the present disclosure provides a solution for determining PUCCH transmission resources of PUCCH formats 3 / 4 / 5 in the above situation.

[0201] According to the first scheme, in the above case, the BS can separately configure PUCCH transmission resources of PUCCH formats 3 / 4 / 5 in the EN-DC UE through a higher signal. In addition to the multiple resources (resources mapped to the TPC command field) used to send the aforementioned PUCCH formats, the BS can configure additional PUCCH resources to be used in this problem case. In this problem case, the EN-DC UE receives resources through a higher signal and sends a PUCCH format including HARQ-ACK feedback through the resources configured by the higher signal.

[0202] According to the second scheme, in the above case, the BS can use the "TPC command" field within the first PDCCH / EPDCCH to indicate the PUCCH transmission resources of PUCCH format 3 / 4 / 5 in the EN-DC UE. Therefore, when sending the PUCCH format, the EN-DC UE uses the "TPC command" field for power control, and uses the "TPC command" field for determining the resources used to send the PUCCH format. That is, the EN-DC UE sends the PUCCH format by controlling the power based on the value of the "TPC command" field in the resources indicated based on the value of the "TPC command" field within the first PDCCH / EPDCCH.

[0203] According to the third solution, in the above case, the EN-DC UE uses one of the multiple resources (resources mapped to the TPC command field) used by default to send the PUCCH format. That is, the resource used in the above problem case among the multiple resources is defined in the standard. The EN-DC UE sends the PUCCH format including the HARQ ACK feedback in the predefined resources.

[0204] According to the fourth scheme, in the above-mentioned problem situation, the EN-DC UE sends PUCCH format 1a / 1b including HARQ ACK / NACK feedback instead of PUCCH format 3 / 4 / 5. In this case, the transmission resources of PUCCH format 1a / 1b can be implicitly mapped to the transmission resources of PDCCH / EPDCCH received in the problem situation. In order to prevent PUCCH transmission resource conflicts for existing LTE UEs, the BS can send an offset value to be added to the PUCCH transmission resources to the EN-DC UE through a higher signal. The EN-DC UE can determine the transmission resources based on the implicitly mapped PUCCH transmission resources and the offset value. For example, the EN-DC UE that has received the offset value determines the transmission resources of PUCCH format 1a / 1b by adding the offset value to the PUCCH transmission resources implicitly mapped to the received PDCCH / EPDCCH transmission resources, and sends PUCCH format 1a / 1b in the determined transmission resources.

[0205] <Solution for avoiding interference caused by LTE UL or NR UL transmission on LTE DL reception or NR DL reception when LTE FDD is the primary cell and NR is the secondary cell>

[0206] Refer to the following description and Fig.11 and Fig.12 , describes various embodiments of a scheme for avoiding interference effects on LTE DL reception or NR DL reception due to LTE UL or NR UL transmission if a UE is configured with EN-DC in which LTE FDD is the primary cell and NR is the secondary cell.

[0207] Fig.11 is a diagram showing a first interference situation to be solved according to an embodiment of the present disclosure. Fig.11 Description Avoiding the impact due to IM interference. If simultaneous UL transmission occurs in the UL carrier of the LTE cell and the UL carrier of the NR cell in a specific band combination (e.g., LTE band 3 and NR band 77), the intermodulation products from the simultaneous UL transmission may interfere with the DL reception in the DL carrier of the LTE cell. Therefore, performance degradation of DL reception may occur. The above interference is called IM interference. The BS can configure the band combination in the UE through a higher signal.

[0208] refer to Fig.11 , LTE 1101 or 1103 is an MCG and operates as FDD, and NR 1102 or 1104 is an SCG. Therefore, the present disclosure can be applied to the case where the UE is configured with EN-DC. Fig.11 , LTE 1101 or 1103 is an FDD cell. By receiving DL carrier and UL carrier information from system information, the EN-DC UE can know the DL carrier and UL carrier information of the FDD cell. The EN-DC UE can receive UL or DL ​​information about NR 1102 or 1104, or information about the position or number of OFDM symbols and flexible time slots from system information, higher information, or a physical layer signal.

[0209] refer to Fig.11, the EN-DC UE may receive DL data from a BS (eNB or gNB) in an LTE or NR cell. If the EN-DC UE has received DL data through the LTE cell in subframe #9, the EN-DC UE sends feedback on the DL data in the UL carrier of the LTE cell in subframe #3 (1112) based on the PDSCH to PUCCH HARQ timing (1111) defined for LTE FDD. In this case, if the EN-DC UE receives scheduling of UL transmission from the gNB in ​​slot #3 of the NR cell matching subframe #3, the EN-DC UE has LTE DL reception affected by IM interference due to intermodulation of the two UL transmissions. One possible way to avoid IM interference is to avoid DL scheduling that generates UL transmission based on BS implementation. Although the gNB has scheduled NR UL transmission in slot #3, the eNB can avoid scheduling DL data in subframe #9 so that the EN-DC UE does not perform LTE UL transmission in subframe #3. According to the above scheme, by preventing the EN-DC UE from performing two UL transmissions simultaneously, interference effects on the LTE DL reception of the EN-DC UE can be avoided. However, the above scheme may cause DL performance degradation because it must avoid DL scheduling.

[0210] One solution for avoiding IM interference while preventing the above-mentioned DL performance degradation is to restrict LTE UL transmission to specific subframes where NR UL transmission does not occur, and define the PDSCH to PUCCH HARQ timing so that UL transmission occurs in this specific subframe. Fig.11 The bottom of FIG. 8 shows an example of applying the HARQ timing in Table 8. That is, by allowing the EN-DC UE to use the timing defined for UL / DL configuration #2 (or reference TDD configuration) as the PDSCH to PUCCH HARQ timing (1113, 1114), LTE UL transmission can be performed only in subframe #2 or #7 (1115, 1117, and 1119). NR UL transmission can be performed only in the remaining time slots 1116, 1118, and 1120 that do not match subframe #2 or #7 in time.

[0211] If the UE is configured with EN-DC, that is, the UE is configured to use an MCG for E-UTRA radio access and an SCG for NR radio access, the UE may receive a configuration of a maximum power value for the UL of LTE and a maximum power value for the UL of NR from an LTE BS or an NR BS. In addition, the UE receives a configuration of a maximum power value for EN-DC operation from an LTE BS or an NR BS. In this case, if the sum of the maximum power value for the UL of LTE and the maximum power value for the UL of NR is greater than the maximum power value for EN-DC operation, the UE may apply one of semi-static power sharing and dynamic power sharing. In this case, the UE may report to the BS through a higher signal that it does not support the capability of simultaneous UL transmission. Optionally, the UE may report through a higher signal that it does not support the capability of simultaneous UL transmission for a specific frequency band combination including an LTE TDD cell or carrier and an NR cell or carrier.

[0212] Semi-static power sharing between MCG (LTE) and SCG (NR) is described. When receiving a reference TDD configuration that limits LTE UL transmission only in specific subframes for LTE UL transmission, if the UE does not indicate or report dynamic power sharing capability to the BS, the UE does not expect NR UL transmission (or does not expect configuration or scheduling indicating NR UL transmission from the NR BS) in a time slot of NR that matches a time interval in which LTE is a UL subframe based on the reference TDD configuration. By configuring, the UE can avoid IM interference.

[0213] Dynamic power sharing between MCG (LTE) and SCG (NR) is described. If the UE indicates or reports the dynamic power sharing capability to the BS, the UE with dynamic power sharing capability for UL transmission does not limit its LTE and NR UL transmissions to specific subframes or time slots, but requires a scheme for determining which UL transmission priority will be given if the LTE and NR UL transmissions conflict with each other in time. If the UE's LTE UL transmission and NR UL transmission conflict with each other, and the sum of the power used for LTE UL transmission and the power used for NR UL transmission is greater than the maximum power value for EN-DC operation, or in order to avoid the influence due to IM interference, the UE can discard the NR UL transmission. As a second scheme, the UE can reduce the NR UL transmission power so that the sum of the power used for LTE UL transmission and the power used for NR UL transmission is less than the maximum power value for EN-DC operation. Optionally, when the NR UL transmission power is reduced, if the transmission power to be reduced is greater than X, the UE can discard the NR transmission. If the transmission power to be reduced is less than X, the UE can perform NR UL transmission using the reduced transmission power.

[0214] Fig.12 is a diagram showing a second interference situation to be solved according to an embodiment of the present disclosure. Fig.12 Description Avoiding the impact of harmonic interference. If UL transmission occurs in the UL carrier of an LTE cell in a specific band combination (e.g., LTE Band 3 and NR Band 77 or NR Band 78), the harmonics due to the UL transmission may interfere with the DL reception in the NR cell. Therefore, the performance of DL reception may be degraded. The above interference is called harmonic interference. The BS (eNB or gNB) can configure the band combination in the UE through a higher signal.

[0215] refer to Fig.12 , LTE 1201 or 1203 is MCG and operates as FDD, and NR 1202 or 1204 is SCG. Therefore, the present disclosure can be applied to the case where the UE is configured with EN-DC. Fig.12 In the example, LTE 1201 or 1203 is an FDD cell, and the EN-DC UE can know the DL carrier and UL carrier information of the FDD cell by receiving the DL carrier and UL carrier information from the system information. The EN-DC UE can receive information about the UL or DL ​​of NR 1202 or 1204, or information about the position or number of flexible time slots and OFDM symbols from the system information, higher information, or a physical layer signal.

[0216] exist Fig.12 In the embodiment of the present invention, an EN-DC UE may receive DL data from a BS (eNB or gNB) in an LTE or NR cell. If the EN-DC UE has received DL data through the LTE cell in subframe #0, the EN-DC UE sends feedback on the DL data in the UL carrier of the LTE cell in subframe #4 based on the PDSCH to PUCCH HARQ timing (1211) defined for LTE FDD. In this case, if the EN-DC UE has received DL data from the gNB in ​​slot #4 of the NR cell matching the subframe #4 time, the EN-DC UE subjects its NR DL reception to interference due to harmonics attributed to the UL transmission (1212). One possible way to avoid harmonic interference is to avoid DL scheduling that generates UL transmission based on the BS implementation. Although the gNB has sent NR DL data in slot #4, the eNB can avoid scheduling the DL data in subframe #0 so that the EN-DC UE does not perform LTE UL transmission in subframe #4. Through the above scheme, interference effects on NR DL reception of EN-DC UEs can be avoided by preventing EN-DC UEs from performing LTE UL transmission in time slots in which NR DL data is received. However, the above scheme may result in DL performance degradation because LTE DL scheduling must be avoided.

[0217] A solution to avoid harmonic interference while preventing the above-mentioned DL performance degradation is to restrict LTE UL transmissions to specific subframes in which NR UL transmissions occur, and to define the PDSCH to PUCCH HARQ timing so that UL transmissions occur in specific subframes. Fig.12 The bottom of FIG. 8 shows an example in which the HARQ timing in Table 8 is applied. That is, by allowing the EN-DC UE to use the timing defined for UL / DL configuration #2 (or reference TDD configuration) as the PDSCH to PUCCH HARQ timing (1213, 1214), LTE UL transmission can be performed only in subframe #2 or #7 in which the UL slot (1215, 1216, 1217) including NR UL transmission occurs. Therefore, harmonic interference to NR DL reception can be avoided. In addition to UL slots #2 and #7, NR UL transmission can be performed even in the remaining slots.

[0218] If the UE is configured with EN-DC, that is, the UE is configured to use an MCG for E-UTRA radio access and is configured to use an SCG for NR radio access, the UE may receive a configuration of a UL maximum power value for LTE and a UL maximum power value for NR from an LTE BS or an NR BS. In addition, the UE receives a configuration of a maximum power value for EN-DC operation from an LTE BS or an NR BS. In this case, if the sum of the maximum power value for the UL of LTE and the maximum power value for the UL of NR is greater than the maximum power value for EN-DC operation, the UE may apply one of semi-static power sharing and dynamic power sharing. In this case, the UE may report to the BS through a higher signal the ability to not support simultaneous UL transmission. Optionally, the UE may report through a higher signal the ability to not support simultaneous UL transmission for a specific frequency band combination including an LTE TDD cell or carrier and an NR cell or carrier.

[0219] Semi-static power sharing between MCG (LTE) and SCG (NR) is described. If a UE receives a reference TDD configuration that limits LTE UL transmission only in a specific subframe for LTE UL transmission, when the UE does not indicate or report dynamic power sharing capability to the BS, the UE expects LTE UL transmission only in LTE UL subframes configured to perform LTE UL transmission based on the reference TDD configuration (or does not expect configuration or scheduling from the LTE BS indicating LTE UL transmission in UL subframes other than the UL subframe). With the above configuration, the UE can avoid harmonic interference.

[0220] Dynamic power sharing between MCG (LTE) and SCG (NR) is described. If the UE indicates or reports the dynamic power sharing capability to the BS, the UE with dynamic power sharing capability for UL transmission does not limit its LTE and NR UL transmissions to specific subframes or time slots. In contrast, if an NR time slot other than an NR time slot matching an LTE UL subframe configured to perform LTE UL transmission based on a reference TDD configuration is indicated as an UL time slot, NR UL transmission is scheduled, LTE UL transmission is scheduled outside the LTE UL subframe, and LTE UL transmission and NR DL reception conflict with each other in time, a scheme is required for the UE to determine which operation priority will be given. If the UE's LTE UL transmission and NR UL transmission conflict with each other, and the sum of the power used for the LTE UL transmission and the power used for the NR UL transmission is greater than the maximum power value for EN-DC operation, or in order to avoid the influence due to harmonic interference (if the NR time slot is a DL time slot), the UE may always discard the LTE UL transmission. As a second scheme, the UE may reduce the NR UL transmit power so that the sum of the power used for LTE UL transmission and the power used for NR UL transmission is less than the maximum power value for EN-DC operation. Optionally, when the NR UL transmit power is reduced, if the transmit power to be reduced is greater than X, the UE may discard the NR transmission. If the transmit power to be reduced is less than X, the UE may perform NR UL transmission using the reduced transmit power. In the second scheme, the UE may perform LTE UL transmission using the configured LTE UL transmit power, and if the NR timeslot is a DL timeslot, NR DL reception may be attempted regardless of the influence of harmonic interference.

[0221] If an EN-DC UE is affected by interference to its LTE or NR DL reception due to the above-mentioned IM interference and harmonic interference for a specific frequency band combination, an operation scheme for an EN-DC UE is described.

[0222] If UL transmission occurs in the UL carrier of an LTE cell in a specific band combination (e.g., LTE Band 3 and NR Band 77), the harmonics attributed to the UL transmission may cause harmonic interference to the DL reception in the NR cell. Therefore, the performance of DL reception may be degraded. In addition, if simultaneous UL transmission occurs in the UL carrier of the LTE cell and the UL carrier of the NR cell in the band combination, the intermodulation products from the simultaneous UL transmission may interfere with the DL reception in the DL carrier of the LTE cell. Therefore, the performance of DL reception may be degraded. In this case, in order to solve the above-mentioned interference problem, the EN-DC UE can perform the following operations.

[0223] As a first solution, if the UE does not indicate the capability of not supporting simultaneous UL transmission through a higher signal (i.e., does not indicate the singleUL-Transmission capability or indicates the capability of supporting simultaneous UL transmission), the UE considers the case where the UL subframe of the LTE cell and the UL time slot of the NR cell are matched in time, such as Fig.12 1215, 1216 and 1217 of . Optionally, the UE considers a case where the UL subframe of the LTE cell and the UL time slot of the NR cell are matched in time, and simultaneous UL transmission in the LTE cell and the NR cell is indicated or configured by the BS. Under this condition and situation, the UE performs only LTE UL transmission in LTE subframe #2 or LTE subframe #7, and does not expect NR UL transmission or NR DL reception in NR time slot #2 or NR time slot #7. Optionally, if NR UL transmission is configured or indicated in NR time slots, the UE discards the NR UL transmission. Optionally, if NR DL reception is configured or indicated in NR time slots, the UE does not decode the NR DL reception, or may attempt to decode the NR DL reception by considering harmonic interference. NR UL transmission or NR DL reception may be configured or indicated in NR time slots other than 1215, 1216 and 1217.

[0224] As a second solution, if the UE indicates through a higher signal that it does not support the capability of simultaneous UL transmission, the UE considers the case where the UL subframe of the LTE cell and the UL time slot of the NR cell are matched in time, such as Fig.12 1215, 1216 and 1217 of . Optionally, the UE considers a case where the UL subframe of the LTE cell and the UL time slot of the NR cell are matched in time, and simultaneous UL transmission in the LTE cell and the NR cell is indicated or configured by the BS. In this condition and case, the UE does not expect LTE downlink reception in LTE subframe #2 or LTE subframe #7, or does not decode LTE DL reception.

[0225] As a third solution, no matter which capability the UE indicates, the UE considers the case where the UL subframe of the LTE cell and the UL time slot of the NR cell match in time, such as Fig.12 1215, 1216 and 1217 of . Optionally, the UE considers a case where the UL subframe of the LTE cell and the UL time slot of the NR cell are matched in time, and simultaneous UL transmission in the LTE cell and the NR cell is indicated or configured by the BS. In this condition and case, the UE does not expect LTE DL reception in LTE subframe #2 or LTE subframe #7, or does not decode LTE DL reception.

[0226] As a fourth solution, the UE sends information to the BS (eNB or gNB) about whether the UE prefers single UL transmission (or prefers to avoid IM interference) or simultaneous UL transmission (or prefers to avoid harmonic interference) with respect to a specific frequency band combination. The BS configures a reference TDD configuration in the UE. Therefore, the UE can be scheduled to perform the preferred UL transmission. If the UE indicates that it prefers single UL transmission with respect to the BS through a higher signal, the UE can perform the preferred UL transmission by Fig.11 In the embodiment of the present invention, the HARQ-ACK for the PDSCH transmitted in multiple LTE subframes is transmitted based on a specific LTE UL subframe of the reference TDD configuration. If the UE indicates that it prefers simultaneous UL transmission relative to the BS through a higher signal, in the conventional technology, the UE transmits the HARQ-ACK for the DL data transmitted in one LTE subframe in the LTE UL subframe by applying the n+4 HARQ timing of the LTE FDD cell. In contrast, in the present disclosure, the UE can transmit the HARQ-ACK for the DL data transmitted in one LTE subframe in the LTE UL subframe by applying the n+4 HARQ timing of the LTE FDD cell. Fig.12 In an embodiment of the present invention, HARQ-ACK for PDSCH sent in multiple LTE subframes is sent based on a specific LTE UL subframe of a reference TDD configuration.

[0227] A method is specifically described in which a UE sends information to a BS via a higher signal (capability signaling) as to whether the UE prefers single UL transmission (or prefers to avoid IM interference). The UE may report singleUL-Transmission capability (or not report the capability to support simultaneous UL transmission), and may report tdm-pattern capability. In conventional technology, the UE is basically incapable of simultaneous UL transmission. If the UE reports the singleUL-Transmission capability to the BS, the UE may report its tdm-pattern configuration (or reference TDD setting or reference TDD configuration) that it can support single UL transmission by additionally reporting the tdm-pattern capability. In the present disclosure, the UE is capable of simultaneous UL transmission, so although it is not necessary to report the singleUL-Transmission capability, the singleUL-Transmission capability and tdm-pattern capability may be reported in order to avoid IM interference. The aforementioned singleUL-Transmission capability and tdm-pattern capability are terms used for description, do not limit the present disclosure, and may be understood as given terms used to perform functions similar to the examples described in the present disclosure.

[0228] A method is specifically described in which a UE reports information about whether it prefers simultaneous UL transmission (or prefers to avoid harmonic interference) to a BS through a higher signal (capability signaling). The UE does not report singleUL-Transmission capability (or reports the capability to support simultaneous UL transmission), and may only report tdm-pattern capability. In conventional technology, only when the UE reports the singleUL-Transmission capability to the BS can the UE report that it can support a tdm-pattern configuration (or reference TDD setting or reference TDD configuration) for single UL transmission by additionally reporting the tdm-pattern capability. However, in the present disclosure, the UE is capable of simultaneous UL transmission, so even though the UE is a UE that does not need to report the singleUL-Transmission capability, in order to avoid harmonic interference, it may also only report the tdm-pattern capability without reporting the singleUL-Transmission capability. As a fifth scheme, in a case where the UL subframe of the LTE cell and the UL time slot of the NR cell are matched in time, and simultaneous UL transmission in the LTE cell and the NR cell is indicated or configured by the BS, the UE does not expect LTE DL reception in LTE subframe #2 or LTE subframe #7, or does not decode LTE DL reception. If the BS does not indicate or configure simultaneous UL transmission in the LTE cell and the NR cell, that is, the BS indicates or configures UL transmission in only one of the two cells, the UE decodes LTE DL reception in LTE subframe #2 or LTE subframe #7.

[0229] Fig.13A is a diagram illustrating a BS process according to an embodiment of the present disclosure.

[0230] refer to Fig.13A At operation 1311, the BS sends configuration information of each cell to the UE via system information or a higher signal, as shown in FIG. Fig.11 and 12 and as described in subsequent proposals of the present disclosure. The configuration information may be cell-related information (e.g., at least one of TDD or FDD information, UL / DL carrier frequency, UL / DL frequency band, and UL / DL subcarrier spacing) of an MCG or SCG cell, which is necessary for dual connectivity, or may be configuration information necessary for data transmission and reception in an MCG or SCG. Optionally, the configuration information may include at least one of the configuration information related to various parameters (reference configuration information, HARQ offset, etc.) described in the embodiments of the present disclosure. The BS may be an NR BS using NR wireless access, and may be an E-UTRA BS using E-UTRA wireless access.

[0231] At operation 1312, the BS receives the capability of the UE from the UE, as shown in FIG. Fig.11 and 12 and as described in subsequent proposals of the present disclosure.

[0232] In operation 1313, the BS Fig.11 and Fig.12 The proposal of and the subsequent proposal of the present disclosure configure UL transmission in the UE, and send scheduling information indicating the UL transmission. The BS may be an NR BS using NR radio access, and may be an E-UTRA BS using E-UTRA radio access. The UL transmission configuration may mean a UL transmission that is not indicated by the PDCCH like periodic channel information transmission, but is configured by a higher signal. The UL transmission indicated by the scheduling information may mean a UL transmission that is indicated by the PDCCH like PUSCH transmission or HARQ-ACK transmission and sent by the UE, or may be a UL transmission from the UE, such as PRACH or SRS.

[0233] At operation 1314, the BS Fig.11 and Fig.12 The proposal of and subsequent proposals of the present disclosure receive UL transmission from the UE. The BS may be an NR BS using NR radio access and may be an E-UTRA BS using E-UTRA radio access.

[0234] Fig. 13B is a diagram illustrating a UE process according to an embodiment of the present disclosure.

[0235] refer to Fig. 13B , in operation 1321, as shown in reference Fig.11 and 12 As described in subsequent proposals of the present disclosure, the UE receives configuration information of each cell from the BS through system information or a higher signal. The configuration information may be cell-related information (e.g., at least one of TDD or FDD information, UL / DL carrier frequency, UL / DL frequency band, and UL / DL subcarrier spacing) of an MCG or SCG cell, which is necessary for dual connectivity, or may be configuration information required for data transmission and reception in an MCG or SCG. Optionally, the configuration information may include at least one of the configuration information related to the various parameters (reference configuration information, HARQ offset, etc.) described in the embodiments of the present disclosure. As described in the embodiments of the present disclosure, before receiving the dynamic power sharing capability from the BS through a higher signal, the UE may send capability-related information to the BS. The BS may be an NR BS using NR wireless access, and may be an E-UTRA BS using E-UTRA wireless access.

[0236] At operation 1322, the UE sends the UE's capabilities to the BS, as shown in FIG. Fig.11 and Fig.12 and as described in subsequent proposals of this disclosure.

[0237] In operation 1323, based on Fig.11 and Fig.12 The proposal of and the subsequent proposal of the present disclosure, the UE receives UL transmission configuration information from the BS, and receives scheduling information indicating UL transmission. The BS may be an NR BS using NR radio access, and may be an E-UTRA BS using E-UTRA radio access. The UL transmission configuration information may mean configuration information related to UL transmission, which is not indicated by the PDCCH like periodic channel information transmission, and its transmission is configured by a higher signal configuration. The UL transmission indicated by the scheduling information may mean UL transmission, which is indicated by the PDCCH like PUSCH transmission or HARQ-ACK transmission and transmitted by the UE, or may be a UL transmission from the UE, such as PRACH or SRS.

[0238] At operation 1324, based on Fig.11 and Fig.12 In the proposal of and the subsequent proposal of the present disclosure, the UE performs UL transmission to the BS by controlling the transmission timing and transmission power using the HARQ timing relationship (PDSCH to PUCCH transmission, PDCCH to PUSCH transmission, PUSCH to PDCCH transmission, etc.). As described in the embodiments of the present disclosure, controlling the transmission power may include an operation of dropping the UL transmission or reducing the UL transmission power. The BS may be an NR BS using NR radio access, and may be an E-UTRA BS using E-UTRA radio access.

[0239] Fig.14 is a diagram showing a configuration of a BS according to an embodiment of the present disclosure.

[0240] The controller 1401 may configure the required information according to the BS process of the present disclosure and various embodiments of the present disclosure, and may control the UL transmission timing and UL transmission reception from the UE according to various embodiments of the present disclosure. The controller 1401 may control the LTE or 5G control information transmitter 1405 to send control information, and may send data to the UE or receive data from the UE through the LTE or 5G data transceiver 1407. In addition, the controller 1401 may control the LTE or 5G data transceiver 1407 to send LTE or 5G data to the UE or receive LTE or 5G data from the UE by scheduling the LTE or 5G data through the scheduler 1403.

[0241] The BS device has been configured with a controller 1401, a scheduler 1403, a control information transmitter 1405, and a data transceiver 1407, but the BS device may be configured with a transceiver and a controller. According to various embodiments of the present disclosure, the controller may control the operation of the BS. In the BS device, for convenience, LTE and 5G have been described together, but the BS device may be an NR BS using NR wireless access, and may be an E-UTRA BS using E-UTRA wireless access.

[0242] refer to Fig.15 , is a diagram showing a configuration of a UE according to an embodiment proposed in the present disclosure.

[0243] The controller 1501 may receive the required configuration information and scheduling from the BS according to the UE process of the present disclosure and various embodiments of the present disclosure, and may control the execution of UL transmission configured by the BS or indicated by the scheduling by controlling the UL transmission timing and UL transmission power according to the present disclosure. The UE may receive the UL data channel transmission resource location from the BS, or may multiplex the UL control information with the UL data channel, and transmit the UL data channel through the LTE or 5G control information receiver 1505 and the LTE or 5G data transceiver 1506. The controller 1501 may control the LTE or 5G data transceiver 1506 to send or receive LTE or 5G data scheduled at the received resource location to the LTE BS or 5G BS. The UE device has been configured with the controller 1501, the control information transmitter 1505, and the data transceiver 1506, but the UE device may be configured with a transceiver and a controller. According to various embodiments of the present disclosure, the controller may control the operation of the UE. In this figure, for convenience, the LTE and 5G devices have been described as if they were together, but the devices for LTE or 5G may be configured separately. The BS for transmitting or receiving control information and data may be an NR BS using NR radio access, and may be an E-UTRA BS using E-UTRA radio access.

[0244] While the present disclosure has been shown and described with reference to various embodiments thereof, it will be understood by those skilled in the art that various changes in form and details may be made without departing from the spirit and scope of the present disclosure as defined by the appended claims and their equivalents.

Claims

1. A method performed by a terminal in a communication system, the method comprising: Receiving information associated with a reference time division duplex (TDD) configuration for dual uplink transmission in Evolved Universal Terrestrial Radio Access (E-UTRA) New Radio (NR) dual connectivity (EN-DC) from a base station, wherein the reference TDD configuration is used to indicate a subframe in which a terminal configured with EN-DC is allowed to transmit; Sending capability information of the terminal to the base station; and In the case where the uplink transmission for the secondary cell group SCG overlaps with the uplink transmission for the primary cell group MCG in the subframe on the MCG, the uplink transmission for the MCG is sent to the base station without sending the uplink transmission for the SCG. The capability information indicates a capability of supporting dynamic power sharing between E-UTRA and NR for EN-DC, and the capability information does not indicate a capability of supporting information for dual UL transmission in EN-DC.

2. The method according to claim 1, wherein: The primary cell associated with the MCG corresponds to a frequency division duplex FDD cell.

3. The method according to claim 1, further comprising: Identify that the sum of the power used for the uplink transmission of the MCG and the power used for the uplink transmission of the SCG is greater than the configured maximum power.

4. The method according to claim 1, in, The MCG is associated with the Long Term Evolution (LTE) radio access technology (RAT), and Among them, SCG is associated with NR RAT.

5. A method performed by a base station in a communication system, the method comprising: Sending information associated with a reference time division duplex (TDD) configuration for dual uplink transmission in Evolved Universal Terrestrial Radio Access (E-UTRA) New Radio (NR) dual connectivity (EN-DC) to a terminal, wherein the reference TDD configuration is used to indicate a subframe in which a terminal configured with EN-DC is allowed to transmit; receiving, from the terminal, capability information of the terminal; and The slave terminal receives an uplink transmission for the master cell group MCG, Wherein, when the uplink transmission for the secondary cell group SCG overlaps with the uplink transmission for the MCG in the subframe on the MCG, the uplink transmission for the MCG is sent instead of the uplink transmission for the SCG. The capability information indicates a capability of supporting dynamic power sharing between E-UTRA and NR for EN-DC, and the capability information does not indicate a capability of supporting information for dual UL transmission in EN-DC.

6. The method according to claim 5, wherein: The primary cell associated with the MCG corresponds to a frequency division duplex FDD cell.

7. The method according to claim 5, wherein: The terminal recognizes that the sum of the power used for the uplink transmission of the MCG and the power used for the uplink transmission of the SCG is greater than the configured maximum power.

8. The method according to claim 5, in, The MCG is associated with the Long Term Evolution (LTE) radio access technology (RAT), and Among them, SCG is associated with NR RAT.

9. A terminal in a communication system, the terminal comprising: Transceiver; as well as At least one processor configured to: receiving, from a base station, information associated with a reference time division duplex (TDD) configuration for dual uplink transmission in Evolved Universal Terrestrial Radio Access (E-UTRA) New Radio (NR) dual connectivity (EN-DC), wherein the reference TDD configuration is used to indicate a subframe in which a terminal configured with EN-DC is allowed to transmit; Sending terminal capability information to the base station; as well as In the case where the uplink transmission for the secondary cell group SCG overlaps with the uplink transmission for the primary cell group MCG in the subframe on the MCG, the uplink transmission for the MCG is sent to the base station without sending the uplink transmission for the SCG. The capability information indicates a capability of supporting dynamic power sharing between E-UTRA and NR for EN-DC, and the capability information does not indicate a capability of supporting information for dual UL transmission in EN-DC.

10. The terminal according to claim 9, wherein: The at least one processor is further configured to identify that a sum of a power for uplink transmission of the MCG and a power for uplink transmission of the SCG is greater than a configured maximum power, The primary cell associated with the MCG corresponds to a frequency division duplex FDD cell, and Among them, MCG is associated with the Long Term Evolution LTE radio access technology RAT, and SCG is associated with the NR RAT.

11. A base station in a communication system, the base station comprising: Transceiver; as well as At least one processor configured to: Sending information associated with a reference time division duplex (TDD) configuration for dual uplink transmission in Evolved Universal Terrestrial Radio Access (E-UTRA) New Radio (NR) dual connectivity (EN-DC) to a terminal, wherein the reference TDD configuration is used to indicate a subframe in which a terminal configured with EN-DC is allowed to transmit; receiving, from the terminal, information about the terminal's capabilities, and The slave terminal receives an uplink transmission for the master cell group MCG, Wherein, when the uplink transmission for the secondary cell group SCG overlaps with the uplink transmission for the MCG in the subframe on the MCG, the uplink transmission for the MCG is sent instead of the uplink transmission for the SCG. The capability information indicates a capability of supporting dynamic power sharing between E-UTRA and NR for EN-DC, and the capability information does not indicate a capability of supporting information for dual UL transmission in EN-DC.

12. The base station according to claim 11, wherein: The capability information received from the terminal indicates the capability of dynamic power sharing between the MCG and the SCG, Among them, the primary cell associated with the MCG corresponds to the frequency division duplex FDD cell, The terminal identifies the sum of the uplink transmission power for the MCG and the uplink transmission power for the SCG as being greater than the configured maximum power, and Among them, MCG is associated with the Long Term Evolution LTE radio access technology RAT, and SCG is associated with the NR RAT.

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