WO2019216612A1 - Method and apparatus for controlling uplink transmission power by terminal for dual connectivity in wireless communication system - Google Patents

Abstract

The present disclosure relates to a communication technique for convergence of IoT technology and a 5G communication system for supporting a higher data transfer rate beyond a 4G system, and a system therefor. The present disclosure can be applied to intelligent services (e.g., smart homes, smart buildings, smart cities, smart or connected cars, health care, digital education, retail business, and services associated with security and safety) on the basis of 5G communication technology and IoT-related technology. Disclosed are a method and an apparatus for controlling uplink-transmitted transmission power in a wireless communication system.

Description

Method and apparatus for controlling uplink transmission power of terminal for dual access in wireless communication system

The present invention relates to a transmission power control method and apparatus for uplink transmission in a wireless communication system.

In order to meet the increasing demand for wireless data traffic since the commercialization of 4G communication systems, efforts are being made to develop improved 5G communication systems or pre-5G communication systems. For this reason, a 5G communication system or a pre-5G communication system is called a system after a 4G network (Beyond 4G Network) or a system after an LTE system (Post LTE).

In order to achieve high data rates, 5G communication systems are being considered for implementation in the ultra-high frequency (mmWave) band (eg, such as the 60 Gigabit (60 GHz) band). In order to mitigate the path loss of radio waves in the ultra-high frequency band and increase the propagation distance of radio waves, beamforming, massive array multiple input / output (FD-MIMO), and FD-MIMO are used in 5G communication systems. Array antenna, analog beam-forming, and large scale antenna techniques are discussed. In addition, in order to improve the network of the system, 5G communication systems have advanced small cells, advanced small cells, cloud radio access network (cloud RAN), ultra-dense network (ultra-dense network) , Device to Device communication (D2D), wireless backhaul, moving network, cooperative communication, Coordinated Multi-Points (CoMP), and interference cancellation The development of such technology is being done.

In addition, in 5G systems, Hybrid FSK and QAM Modulation (FQAM) and Slide Window Superposition Coding (SWSC), Advanced Coding Modulation (ACM), and FBMC (Filter Bank Multi Carrier) and NOMA are advanced access technologies. (non orthogonal multiple access), and sparse code multiple access (SCMA) are being developed.

Meanwhile, the Internet is evolving from a human-centered connection network in which humans create and consume information, and an Internet of Things (IoT) network that exchanges and processes information between distributed components such as things. The Internet of Everything (IoE) technology, which combines big data processing technology through connection with cloud servers and the like, is emerging. In order to implement the IoT, technical elements such as sensing technology, wired / wireless communication and network infrastructure, service interface technology, and security technology are required, and recently, a sensor network for connection between things, a machine to machine , M2M), Machine Type Communication (MTC), etc. are being studied. In an IoT environment, intelligent Internet technology (IT) services can be provided that collect and analyze data generated from connected objects to create new value in human life. IoT is a field of smart home, smart building, smart city, smart car or connected car, smart grid, health care, smart home appliances, advanced medical services, etc. through convergence and complex of existing information technology (IT) technology and various industries. It can be applied to.

Accordingly, various attempts have been made to apply the 5G communication system to the IoT network. For example, technologies such as sensor network, machine to machine (M2M), machine type communication (MTC), and the like, are implemented by techniques such as beamforming, MIMO, and array antennas. It is. Application of cloud radio access network (cloud RAN) as the big data processing technology described above may be an example of convergence of 5G technology and IoT technology.

On the other hand, various studies on the transmission scheme of the uplink control channel in the communication system has been made, and in particular, the scheme for transmitting the Physical Uplink Control Channel (PUCCH) has been discussed at various angles.

A terminal capable of dual access to LTE and NR may transmit and receive data for LTE and NR cells, respectively, wherein the uplink transmission power of the terminal is limited by the maximum power of the terminal.

Accordingly, one object of the present invention, according to whether the LTE cell is a master cell group (MCG) or the NR cell is MCG, or the processing time of the uplink transmission of the terminal, if the uplink transmission occurs simultaneously in the LTE cell and the NR cell A method and apparatus for controlling uplink transmit power, such as reducing transmit power or dropping transmissions in a particular cell.

In a wireless communication system according to an embodiment of the present invention for solving the above problems, dual connectivity with a first base station based on a first radio access technology and a second base station based on a second radio access technology is established. In the terminal method, Receiving a downlink signal from the first base station, the transmission timing of the first uplink signal corresponding to the downlink signal is the transmission of the second uplink signal to the second base station Checking whether the timing overlaps, and when the transmission timing of the first uplink signal and the transmission timing of the second uplink signal overlap, the first transmission power and the second uplink transmission for the first uplink transmission are performed. Checking whether a sum of second transmission powers for the power supply exceeds a maximum transmission power of the terminal, and adding the first transmission power and the second transmission power If the maximum transmit power of the terminal is exceeded, the method may include controlling the second transmit power based on a processing time for transmitting the first uplink signal.

In addition, in the wireless communication system according to an embodiment of the present invention, based on the first radio access technology, and supports a dual connectivity (dual connectivity) to the terminal between the second base station based on the second radio access technology A first base station method, comprising: transmitting a downlink signal to the terminal and receiving a first uplink signal corresponding to the downlink signal from the terminal based on a first transmission power; The second transmission power for the transmission of the second uplink signal from the terminal to the second base station, the transmission timing of the first uplink signal overlaps with the transmission timing of the second uplink signal, the first If the sum of the transmit power and the second transmit power exceeds the maximum transmit power of the terminal, the first uplink signal processing time of the terminal is based on the It may be controlled by the horse.

In addition, in a wireless communication system according to an embodiment of the present invention, a terminal for performing dual connectivity with a first base station based on a first radio access technology and a second base station based on a second radio access technology, The transceiver is controlled to receive a downlink signal from the transceiver and the first base station, and the transmission timing of the first uplink signal corresponding to the downlink signal is transmitted to the second base station. Check whether the timing overlaps, and when the transmission timing of the first uplink signal and the transmission timing of the second uplink signal overlap, the first transmission power and the second uplink signal for the transmission of the first uplink signal. Determine whether the sum of the second transmission power for the transmission exceeds the maximum transmission power of the terminal, and the first transmission power and the second transmission power If it exceeds the maximum transmit power of the terminal, on the basis of processing (processing) time for the first transmission of the uplink signal may be a control unit for controlling the second transmission power.

In addition, in the wireless communication system according to an embodiment of the present invention, based on the first radio access technology, and supports a dual connectivity (dual connectivity) to the terminal between the second base station based on the second radio access technology In the first base station, the transceiver unit to transmit a downlink signal to the transceiver and the terminal, and to receive a first uplink signal corresponding to the downlink signal from the terminal, based on a first transmission power And a control unit for controlling the second transmission power for the transmission of the second uplink signal from the terminal to the second base station, wherein the transmission timing of the first uplink signal is the transmission timing of the second uplink signal. If the sum of the first transmit power and the second transmit power exceeds the maximum transmit power of the terminal, the first uplink signal processing (p) of the terminal; rocessing) may be controlled by the terminal based on the time.

According to an embodiment of the present invention, the present invention, when the terminal is supported dual connectivity is set up dual connectivity from the LTE base station and the NR base station, in consideration of whether the MCG LTE or NR cell and the upstream processing time of the terminal Even if uplink transmission occurs simultaneously in the LTE cell and the NR cell, uplink transmission can be performed by controlling the transmit power within the maximum transmit power value of the UE.

1 illustrates a basic structure of a time-frequency domain in an LTE system.

2 is a diagram illustrating an example in which 5G services are multiplexed and transmitted in one system.

3 is a diagram illustrating an embodiment of a communication system to which the present invention is applied.

4 is a diagram illustrating a method of controlling power of uplink transmission according to Embodiments 1 and 2 of the present invention.

FIG. 5 is a diagram illustrating a scheme for controlling power of uplink transmission according to Embodiments 3 and 4 of the present invention.

FIG. 6 is a diagram illustrating a scheme for controlling power of uplink transmission according to Embodiments 5 and 6 of the present invention.

7 is a diagram illustrating a method of controlling power of uplink transmission according to Embodiment 7 of the present invention.

8 is a diagram illustrating a scheme for controlling power of uplink transmission according to Embodiment 8 of the present invention.

9 is a diagram illustrating a scheme for controlling power of uplink transmission according to Embodiment 9 of the present invention.

10 is a diagram illustrating a base station and a terminal procedure according to embodiments of the present invention.

11 illustrates a base station apparatus according to embodiments of the present invention.

12 is a diagram illustrating a terminal device according to embodiments of the present invention.

Hereinafter, embodiments of the present invention will be described in detail with the accompanying drawings. In addition, in describing the present invention, when it is determined that a detailed description of a related known function or configuration may unnecessarily obscure the subject matter of the present invention, the detailed description thereof will be omitted. Terms to be described later are terms defined in consideration of functions in the present invention, and may be changed according to intentions or customs of users or operators. Therefore, the definition should be made based on the contents throughout the specification.

Advantages and features of the present invention, and methods for achieving them will be apparent with reference to the embodiments described below in detail in conjunction with the accompanying drawings. However, the present invention is not limited to the embodiments disclosed below, but can be implemented in various forms. It is provided to fully convey the scope of the invention to those skilled in the art, and the present invention is defined only by the scope of the claims. Like reference numerals refer to like elements throughout.

At this point, it will be appreciated that each block of the flowchart illustrations and combinations of flowchart illustrations may be performed by computer program instructions. Since these computer program instructions may be mounted on a processor of a general purpose computer, special purpose computer, or other programmable data processing equipment, those instructions executed through the processor of the computer or other programmable data processing equipment may be described in flow chart block (s). It creates a means to perform the functions. These computer program instructions may be stored in a computer usable or computer readable memory that can be directed to a computer or other programmable data processing equipment to implement functionality in a particular manner, and thus the computer usable or computer readable memory. It is also possible for the instructions stored in to produce an article of manufacture containing instruction means for performing the functions described in the flowchart block (s). Computer program instructions may also be mounted on a computer or other programmable data processing equipment, such that a series of operating steps may be performed on the computer or other programmable data processing equipment to create a computer-implemented process to create a computer or other programmable data. Instructions for performing the processing equipment may also provide steps for performing the functions described in the flowchart block (s).

In addition, each block may represent a portion of a module, segment, or code that includes one or more executable instructions for executing a specified logical function (s). It should also be noted that in some alternative implementations, the functions noted in the blocks may occur out of order. For example, the two blocks shown in succession may in fact be executed substantially concurrently, or the blocks may sometimes be executed in the reverse order, depending on the corresponding function.

In this case, the term '~ part' used in the present embodiment refers to software or a hardware component such as an FPGA or an ASIC, and '~ part' plays certain roles. However, '~' is not meant to be limited to software or hardware. '~ Portion' may be configured to be in an addressable storage medium or may be configured to play one or more processors. Thus, as an example, '~' means components such as software components, object-oriented software components, class components, and task components, and processes, functions, properties, procedures, and the like. Subroutines, segments of program code, drivers, firmware, microcode, circuits, data, databases, data structures, tables, arrays, and variables. The functionality provided within the components and the 'parts' may be combined into a smaller number of components and the 'parts' or further separated into additional components and the 'parts'. In addition, the components and '~' may be implemented to play one or more CPUs in the device or secure multimedia card.

Hereinafter, embodiments of the present invention will be described in detail with the accompanying drawings. In addition, in describing the present invention, when it is determined that a detailed description of a related known function or configuration may unnecessarily obscure the subject matter of the present invention, the detailed description thereof will be omitted. Terms to be described later are terms defined in consideration of functions in the present invention, and may be changed according to intentions or customs of users or operators. Therefore, the definition should be made based on the contents throughout the specification.

In addition, in describing the embodiments of the present invention in detail, an OFDM-based wireless communication system, in particular the 3GPP EUTRA standard will be the main target, but the main subject of the present invention is another communication system having a similar technical background and channel form. In addition, it is possible to apply with a slight modification in the range without departing greatly from the scope of the present invention, which will be possible in the judgment of those skilled in the art.

In order to meet the increasing demand for wireless data traffic since the commercialization of 4G communication systems, efforts are being made to develop improved 5G communication systems or pre-5G communication systems. For this reason, a 5G communication system or a pre-5G communication system is called a Beyond 4G network communication system or a post LTE system. In order to achieve high data rates, 5G communication systems are being considered for implementation in the ultra-high frequency (mmWave) band (eg, such as the 60 Gigabit (60 GHz) band). In order to mitigate the path loss of radio waves in the ultra-high frequency band and increase the propagation distance of radio waves, beamforming, massive array multiple input / output (FD-MIMO), and FD-MIMO are used in 5G communication systems. Array antenna, analog beam-forming, and large scale antenna techniques are discussed.

In addition, in order to improve the network of the system, in the 5G communication system, an advanced small cell, an advanced small cell, a cloud radio access network (cloud RAN), an ultra-dense network ), Device to Device communication (D2D), wireless backhaul, moving network, cooperative communication, Coordinated Multi-Points (CoMP), and interference cancellation Technology development, etc. In addition, in 5G systems, Hybrid FSK and QAM Modulation (FQAM) and Slide Window Superposition Coding (SWSC), Advanced Coding Modulation (ACM), and FBMC (Filter Bank Multi Carrier) and NOMA are advanced access technologies. Non-orthogonal multiple access and sparse code multiple access are being developed.

Meanwhile, the Internet is evolving from a human-centered connection network where humans create and consume information, and an Internet of Things (IoT) network that exchanges and processes information among distributed components such as things. The Internet of Everything (IoE) technology, which combines big data processing technology through connection with cloud servers and the like, is emerging. In order to implement the IoT, technical elements such as sensing technology, wired / wireless communication and network infrastructure, service interface technology, and security technology are required, and recently, a sensor network for connection between things, a machine to machine , M2M), Machine Type Communication (MTC), etc. are being studied. In an IoT environment, intelligent Internet technology (IT) services can be provided that collect and analyze data generated from connected objects to create new value in human life. IoT is a field of smart home, smart building, smart city, smart car or connected car, smart grid, health care, smart home appliances, advanced medical services, etc. through convergence and complex of existing information technology (IT) technology and various industries. It can be applied to.

Accordingly, various attempts have been made to apply the 5G communication system to the IoT network. For example, technologies such as sensor network, machine to machine (M2M), machine type communication (MTC), and the like, are implemented by techniques such as beamforming, MIMO, and array antennas. It is. Application of cloud radio access network (cloud RAN) as the big data processing technology described above may be an example of convergence of 5G technology and IoT technology.

On the other hand, the research on the coexistence of the new 5G communication (or NR communication in the present invention) and the existing LTE communication in the same spectrum in the mobile communication system.

The present invention relates to a wireless communication system, and more particularly, different wireless communication systems coexist at one carrier frequency or multiple carrier frequencies, and a terminal capable of transmitting and receiving data in at least one communication system among different communication systems. The present invention relates to a method and an apparatus for transmitting and receiving data with each communication system.

In general, mobile communication systems have been developed to provide voice services while guaranteeing user activity. However, mobile communication systems are gradually expanding to not only voice but also data services, and have now evolved to provide high-speed data services. However, in the mobile communication system in which a service is currently provided, a shortage of resources and users demand faster services, and thus, a more advanced mobile communication system is required.

In response to these demands, one of the systems being developed as a next-generation mobile communication system, a specification work for Long Term Evolution (LTE) is underway in the 3GPP (The 3rd Generation Partnership Project). LTE is a technology that implements high-speed packet-based communication with a transmission rate of up to 100 Mbps. To this end, various methods are discussed. For example, the network structure can be simplified to reduce the number of nodes located on the communication path, or the wireless protocols can be as close to the wireless channel as possible.

The LTE system employs a hybrid automatic repeat request (HARQ) scheme in which the data is retransmitted in the physical layer when a decoding failure occurs in the initial transmission. In the HARQ scheme, when the receiver does not correctly decode the data, the receiver transmits NACK (Negative Acknowledgement) indicating the decoding failure 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 previously decoded data to improve the data reception performance. In addition, when the receiver correctly decodes the data, the transmitter may transmit an acknowledgment (ACK) indicating the decoding success to the transmitter so that the transmitter may transmit new data.

1 is a diagram illustrating a basic structure of a time-frequency domain, which is a radio resource region in which the data or control channel is transmitted in downlink in an LTE system.

In FIG. 1, the horizontal axis represents the time domain and the vertical axis represents the frequency domain. The minimum transmission unit in the time domain is an OFDM symbol, in which Nsymb (102) OFDM symbols are gathered to form one slot 106, and two slots are gathered to form one subframe 105. The length of the slot is 0.5ms and the length of the subframe is 1.0ms. The radio frame 114 is a time domain unit consisting of 10 subframes. The minimum transmission unit in the frequency domain is a subcarrier, and the bandwidth of the entire system transmission bandwidth is composed of a total of NBW 104 subcarriers.

The basic unit of a resource in the time-frequency domain may be represented by an OFDM symbol index and a subcarrier index as a resource element (RE). The resource block 108 (Resource Block; RB or PRB) is defined as Nsymb 102 consecutive OFDM symbols in the time domain and NRB 110 consecutive subcarriers in the frequency domain. Thus, one RB 108 is composed of Nsymb x NRB REs 112. In general, the minimum transmission unit of data is the RB unit. In the LTE system, the above Nsymb = 7, NRB = 12, NBW and NRB is proportional to the bandwidth of the system transmission band.

The data rate increases in proportion to the number of RBs scheduled for the UE. The LTE system defines and operates six transmission bandwidths. In the case of a frequency division duplex (FDD) system in which downlink and uplink are divided into frequencies, the downlink transmission bandwidth and the uplink transmission bandwidth may be different. The channel bandwidth represents a 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, an LTE system with a 10 MHz channel bandwidth consists of 50 RBs in transmission bandwidth.

TABLE 1

The downlink control information is transmitted within the first N OFDM symbols in the subframe. Generally N = {1, 2, 3}. Therefore, the N value varies in each subframe according to the amount of control information to be transmitted in the current subframe. The control information includes a control channel transmission interval indicator indicating how many control information is transmitted over the OFDM symbol, scheduling information for downlink data or uplink data, HARQ ACK / NACK signal, and the like.

In the LTE system, scheduling information on downlink data or uplink data is transmitted from the base station to the terminal through downlink control information (DCI). An uplink (UL) refers to a radio link through which a terminal transmits data or a control signal to a base station, and a downlink (DL) refers to a radio link through which a base station transmits data or a control signal to a terminal. DCI defines various formats to determine whether scheduling information (UL (uplink) grant) for uplink data or scheduling information (DL (downlink) grant) for downlink data and whether compact DCI having a small size of control information. The DCI format is determined according to whether or not it is applied, whether to use spatial multiplexing using multiple antennas, or whether the DCI for power control is applied. For example, DCI format 1 which is scheduling control information (DL grant) for downlink data is configured to include at least the following control information.

Resource allocation type 0/1 flag: Notifies whether the resource allocation method is type 0 or type 1. Type 0 uses the bitmap method to allocate resources in resource block group (RBG) units. In the LTE system, a basic unit of scheduling is a resource block (RB) represented by time and frequency domain resources, and the RBG is composed of a plurality of RBs to become a basic unit of scheduling in a type 0 scheme. Type 1 allows allocating a specific RB within the RBG.

Resource block assignment: Notifies the RB allocated for data transmission. The resource to be expressed is determined by the system bandwidth and the resource allocation method.

Modulation and coding scheme (MCS): Notifies the modulation scheme used for data transmission and the size of the transport block that is the data to be transmitted.

HARQ process number: Notifies the process number of HARQ.

New data indicator: notifies whether HARQ initial transmission or retransmission.

Redundancy version: Notifies the redundant version of the HARQ.

Transmit Power Control (TPC) command for PUCCH (Physical Uplink Control CHannel): Notifies a transmit power control command for PUCCH, which is an uplink control channel.

The DCI is transmitted through a physical downlink control channel (PDCCH) or an enhanced PDCCH (EPDCCH), which is a downlink physical control channel through channel coding and modulation.

In general, the DCI is channel-coded independently for each UE, and then configured and transmitted with each independent PDCCH. In the time domain, the PDCCH is mapped and transmitted during the control channel transmission period. The frequency domain mapping position of the PDCCH is determined by the identifier (ID) of each terminal and spread over the entire system transmission band.

The downlink data is transmitted through a physical downlink shared channel (PDSCH) which is a physical channel for downlink data transmission. PDSCH is transmitted after the control channel transmission interval, and scheduling information such as specific mapping positions and modulation schemes in the frequency domain is informed by the DCI transmitted through the PDCCH.

The base station notifies the UE of a modulation scheme applied to a PDSCH to be transmitted and a transport block size (TBS) of data to be transmitted through an MCS configured of 5 bits among control information constituting the DCI. The TBS corresponds to a size before channel coding for error correction is applied to data (transport block, TB) that the base station intends to transmit.

Modulation methods supported by the LTE system are Quadrature Phase Shift Keying (QPSK), Quadrature Amplitude Modulation (16QAM), and 64QAM. Each modulation order (Qm) corresponds to 2, 4, and 6. That is, 2 bits per symbol for QPSK modulation, 4 bits per symbol for 16QAM modulation, and 6 bits per symbol for 64QAM modulation.

In 3GPP LTE Rel-10, bandwidth extension technology has been adopted to support higher data throughput compared to LTE Rel-8. This technique, called bandwidth extension or carrier aggregation (CA), can increase the amount of data transmission by an extended band compared to an LTE Rel-8 terminal that transmits data in one band by extending the band. . Each of the bands is called a component carrier (CC), and the LTE Rel-8 terminal is defined to have one component carrier for each of downlink and uplink. In addition, the downlink component carrier and the uplink component carrier connected to the SIB-2 are collectively called a cell. The SIB-2 connection relationship between the downlink component and the uplink component is transmitted as a system signal or a higher signal. The terminal supporting the CA may receive downlink data through a plurality of serving cells and transmit uplink data.

In Rel-10, when a base station is difficult to send a physical downlink control channel (PDCCH) to a specific UE from a specific serving cell, another serving cell transmits the PDCCH and the corresponding PDCCH is a physical downlink shared channel (PDSCH) of another serving cell or As a field indicating that a PUSCH (Physical Uplink Shared Channel) is indicated, a carrier indicator field (CIF) may be set to the UE. The CIF may be set to a terminal supporting the CA. The CIF is determined to indicate another serving cell by adding 3 bits to the PDCCH information in a specific serving cell. The CIF is included only when the CIF is set as an upper signal to perform cross carrier scheduling. If the upper signal is not set to cross carrier scheduling or the upper signal is set to self scheduling, CIF is not included and cross carrier scheduling is not performed at this time. When the CIF is included in downlink allocation information (DL assignment), the CIF indicates a serving cell to which a PDSCH scheduled by DL assignment is to be transmitted, and the CIF is included in UL resource allocation information (UL grant). When present, the CIF is defined to indicate the serving cell to which the PUSCH scheduled by the UL grant is to be transmitted.

As described above, in LTE Rel-10, carrier aggregation (CA), which is a bandwidth extension technology, is defined, and a plurality of serving cells may be configured in the terminal. The terminal transmits channel information about the plurality of serving cells periodically or aperiodically to the base station for data scheduling of the base station. The base station schedules and transmits data for each carrier, and the terminal transmits A / N feedback for the data transmitted for each carrier. In LTE Rel-10, it is designed to transmit A / N feedback of maximum 21 bits, and when A / N feedback and channel information overlap in one subframe, it is designed to transmit A / N feedback and discard channel information. . In LTE Rel-11, up to 22 bits of A / N feedback and one cell channel information are transmitted in PUCCH format 3 from PUCCH format 3 by multiplexing channel information of one cell with A / N feedback. It was.

In LTE Rel-13, a maximum of 32 serving cell configuration scenarios are assumed. The concept of extending the number of serving cells to 32 by using a band in an unlicensed band as well as a licensed band is completed. In addition, in consideration of the limited number of licensed bands such as the LTE frequency, the LTE service has been provided in an unlicensed band such as the 5 GHz band, which is called LAA (Licensed Assisted Access). The LAA applied Carrier aggregation technology in LTE to support the operation of the LTE cell, which is a licensed band, as the P-cell, and the LAA cell, which is the unlicensed band, as the S-cell. Therefore, as in LTE, feedback generated in the LAA cell, which is the SCell, should be transmitted only in the Pcell, and the LAA cell may be freely applied with the downlink subframe and the uplink subframe. Unless stated otherwise in this specification, LTE refers to including all of LTE evolution technology, such as LTE-A, LAA.

On the other hand, as a communication system after LTE, i.e., a fifth generation wireless cellular communication system (hereinafter referred to as 5G or NR), should be able to freely reflect various requirements such as users and service providers. Services that meet the requirements can be supported.

Thus, 5G is referred to as increased mobile broadband communication (eMBB: Enhanced Mobile BroadBand, hereinafter referred to as eMBB), Massive Machine Type Communication (mMTC: referred to herein as mMTC), Various 5G-oriented services such as ultra reliable low delay communication (URLLC: Ultra Reliable and Low Latency Communications, hereinafter referred to as URLLC) in terms of terminal maximum transmission speed of 20Gbps, terminal maximum speed of 500km / h, and maximum delay time of 0.5ms In addition, the terminal access density may be defined as a technology for satisfying the requirements selected for each 5G-oriented services among requirements such as 1,000,000 terminals / km 2.

For example, in order to provide eMBB in 5G, it is necessary to provide a maximum transmission rate of 20 Gbps terminal in downlink and a maximum transmission rate of 10 Gbps terminal in uplink from one base station perspective. At the same time, the actual transmission speed of the terminal should be increased. In order to meet these requirements, improvements in transmission and reception techniques are required, including more advanced multiple-input multiple output transmission techniques.

At the same time, mMTC is being considered to support application services such as the Internet of Thing (IoT) in 5G. In order to efficiently provide the Internet of Things, the mMTC needs a requirement for supporting large terminal access in a cell, improving terminal coverage, improved battery time, and reducing terminal cost. Since the IoT is attached to various sensors and various devices to provide a communication function, it must be able to support a large number of terminals (eg, 1,000,000 terminals / km 2) in a cell. In addition, because of the nature of the service, mMTC is likely to be located in a shadow area such as the basement of a building or an area not covered by a cell, and thus requires more coverage than the coverage provided by an eMBB. The mMTC is likely to be composed of a low cost terminal, and very long battery life time is required because it is difficult to frequently change the battery of the terminal.

Finally, in the case of URLLC, it is a cellular-based wireless communication used for a specific purpose, as a service used for remote control of robots or mechanical devices, industrial automation, unmanned aerial vehicles, remote health control, emergency alerts, etc. In addition, it must provide communications that provide ultra-low latency and ultra-reliability. For example, URLLC must satisfy a maximum latency of less than 0.5 ms, while simultaneously providing a packet error rate of 10-5 or less. Accordingly, a transmission time interval (TTI) smaller than a 5G service such as eMBB is required for URLLC, and a design that needs to allocate a wide resource in a frequency band is required.

The services considered in the above-mentioned fifth generation wireless cellular communication system should be provided as a framework. That is, for efficient resource management and control, it is desirable that each service is integrated and controlled and transmitted as one system rather than operated independently.

2 is a diagram illustrating an example in which services considered in 5G are transmitted to one system.

The frequency-time resource 201 used by 5G in FIG. 2 may consist of a frequency axis 202 and a time axis 203. 2 illustrates that 5G operates eMBB 205, mMTC 206 and URLLC 207 in one framework. In addition, as a service that may be additionally considered in 5G, an enhanced mobile broadcast / multicast service (eMBMS) 208 for providing a broadcast service on a cellular basis may be considered.

Services considered in 5G, such as eMBB 205, mMTC 206, URLLC 207, and eMBMS 208, are time-division multiplexing (TDM) or frequency within one system frequency bandwidth operating at 5G. It may be multiplexed and transmitted through frequency division multiplexing (FDM), and spatial division multiplexing may also be considered. In the case of the eMBB 205, it is desirable to occupy the maximum frequency bandwidth at a certain arbitrary time in order to provide the increased data transmission rate described above. Accordingly, in the case of the eMBB 205 service, it is preferable to transmit TDM in another service and system transmission bandwidth 201, but it is also desirable to transmit FDM in other services and system transmission bandwidth according to the needs of other services. .

In the case of the mMTC 206, unlike other services, an increased transmission interval is required to secure wide coverage, and coverage can be secured by repeatedly transmitting the same packet within the transmission interval. At the same time, there is a limit on the transmission bandwidth that the terminal can receive in order to reduce the complexity of the terminal and the terminal price. Given this requirement, it is desirable for the mMTC 206 to be transmitted in FDM with other services within a 5G transmission system bandwidth 201.

URLLC 207 preferably has a short Transmit Time Interval (TTI) when compared to other services to meet the ultra-delay requirements required by the service. At the same time, it is desirable to have a wide bandwidth on the frequency side because it must have a low coding rate in order to satisfy the super reliability requirements. Given this requirement of URLLC 207, URLLC 207 is preferably TDM with other services within 5G of transmission system bandwidth 201.

Each of the above-described services may have different transmission / reception schemes and transmission / reception parameters in order to satisfy requirements required by each service. For example, each service can have a different numerology based on each service requirement. Numerology is a cyclic prefix (CP) length and subcarrier spacing in a communication system based on Orthogonal Frequency Division Multiplexing (OFDM) or Orthogonal Frequency Division Multiple Access (OFDMA). spacing), OFDM symbol length, transmission interval length (TTI), and the like. As an example of having different numerologies between the above services, the eMBMS 208 may have a longer CP length than other services. Since eMBMS transmits broadcast-based higher traffic, all cells can transmit the same data.

In this case, if a signal received from a plurality of cells arrives within a CP length from the terminal's point of view, since the terminal may receive and decode all of these signals, a single frequency network diversity (SFN) gain may be obtained. Therefore, there is an advantage that the terminal located at the cell boundary can receive broadcast information without coverage limitation. However, when the CP length is relatively long compared to other services in 5G to support eMBMS, a waste of CP overhead is generated, and thus, a long OFDM symbol length is required at the same time as other services. Narrow subcarrier spacing is required.

In addition, as an example in which different numerology is used between services in 5G, in the case of URLLC, a shorter OFDM symbol length may be required as a smaller TTI is required than other services, and at the same time, a wider subcarrier interval may be required.

Meanwhile, in 5G, one TTI may be defined as one slot, and may include 14 OFDM symbols or 7 OFDM symbols. Therefore, in the case of subcarrier spacing of 15KHz, one slot has a length of 1ms or 0.5ms. In addition, in 5G, one TTI can be defined as one mini-slot or sub-slot for emergency transmission and transmission to unlicensed band, and one mini-slot is from 1 (total OFDM of slots). Symbol number) −1 may have the number of OFDM symbols. For example, when the length of one slot is 14 OFDM symbols, the length of the mini slot may be determined from 1 to 13 OFDM symbols. The length, format, and repetition type of the slot or minislot may be defined by the standard or transmitted by higher level signals, system information, or physical signals, and may be received by the terminal. In addition, instead of a mini slot or a sub slot, a slot may be determined from 1 to 14 OFDM symbols, and the length of the slot may be transmitted by an upper signal or system information and may be received by the terminal.

Slots or mini-slots may be defined to have various transmission formats, and may be classified into the following formats.

Downlink-only slot (DL only slot or full DL slot): Downlink-only slot consists of only a downlink period, only downlink transmission is supported.

DL centric slot: A DL centric slot is composed of a down period, a GP (or a flexible symbol), and an up period, and the number of OFDM symbols in the down period is larger than the number of OFDM symbols in the up period.

UL centric slot: The up-centric slot is composed of a downlink section, a GP (or flexible symbol), and an uplink section, and the number of OFDM symbols in the downlink section is smaller than the number of OFDM symbols in the uplink section.

UL dedicated slot (UL only slot or full UL slot): The uplink only slot consists of an uplink only, only uplink transmission is supported.

In the above, only the slot format is classified, but the mini-slot may be classified in the same classification method. That is, it may be classified into a downlink only mini slot, a down center mini slot, an up center mini slot, an uplink dedicated mini slot, and the like. The flexible symbol may be used as a guard symbol for transmission / reception switching and may also be used for channel estimation purposes.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings. In this case, it should be noted that like elements are denoted by like reference numerals as much as possible. In addition, detailed descriptions of well-known functions and configurations that may blur the gist of the present invention will be omitted.

In addition, the embodiments of the present invention will be described in detail, LTE and 5G system will be the main target, but the main subject of the present invention greatly extends the scope of the present invention to other communication systems having a similar technical background and channel form. Applicable in a few variations without departing from the scope, which will be possible in the judgment of those skilled in the art.

Hereinafter, a 5G system for transmitting and receiving data in the 5G cell will be described.

3 is a diagram illustrating an embodiment of a communication system to which the present invention is applied. The drawings illustrate a form in which the 5G system is operated, and the methods proposed in the present invention can be applied to the system of FIG. 3.

3 is a diagram illustrating an example of an integrated system configuration combining a base station in charge of the new radio access technology and an LTE / LTE-A base station.

Referring to FIG. 3, relatively small coverage base stations 303, 305, 307 of coverage 304, 306, 308 may be disposed within coverage 302 of macro base station 301. In general, the macro base station 301 is capable of transmitting signals at a relatively higher transmission power than the small base stations 303, 305, and 307, so that the coverage 302 of the macro base station 301 is the small base stations 303, 305, and 307. Has a relatively larger feature than coverage 304, 306, 308. In the example of FIG. 3, the macro base station represents an LTE / LTE-A system operating in a relatively low frequency band, and the small base stations 303, 305, and 307 represent a new radio access technology (NR or 5G) operating in the relatively high frequency band. ) Is applied to the system.

The macro base station 301 and the small base station 303, 305, 307 are interconnected, and there may be a certain amount of backhaul delay depending on the connection state. Therefore, it may not be desirable to exchange information that is sensitive to transmission delays between the macro base station 301 and the small base station 303, 305, 307.

Meanwhile, the example of FIG. 3 illustrates carrier combining between the macro base station 301 and the small base stations 303, 305, and 307. However, the present invention is not limited thereto, and the present invention is not limited thereto. Applicable for For example, according to the exemplary embodiment, the present invention may be applicable to both carrier combinations between macro base stations and macro base stations located at different locations, or carrier combinations between small base stations and small base stations located at different locations. In addition, the number of carriers combined is not limited.

Referring to FIG. 3, the macro base station 301 may use the frequency f1 for downlink signal transmission, and the small base stations 303, 305, and 307 may use the frequency f2 for downlink signal transmission. In this case, the macro base station 301 may transmit data or control information to the predetermined terminal 309 through the frequency f1, and the small base stations 303, 305, and 307 may transmit data or control information through the frequency f2. . Through such carrier combination, a base station adopting a new radio access technology capable of supporting ultra-wideband in a high frequency band provides an ultra high speed data service and an ultra low delay service, and simultaneously adopts LTE / LTE-A technology in a relatively low frequency band. The base station to be applied may support the mobility of a stable terminal.

Meanwhile, the configuration illustrated in FIG. 3 may be similarly applied to uplink carrier coupling as well as downlink carrier coupling. For example, the terminal 309 may transmit data or control information to the macro base station 301 through the frequency f1 'for uplink signal transmission. The terminal 309 may transmit data or control information to the small base stations 303, 305, and 307 through a frequency f 2 ′ for uplink signal transmission. The f1 'may correspond to the f1, and the f2' may correspond to the f2.

The uplink signal transmission of the terminal may be performed at different times or simultaneously with the macro base station and the small base station. In any case, due to the physical constraints of the power amplifier elements of the terminal and the propagation restrictions on the terminal transmission power, the sum of the uplink transmission powers of the terminal at any moment should be kept within a predetermined threshold.

In the environment as illustrated in FIG. 3, the operation of the terminal 309 that connects to the macro base station 301 and the small base stations 303, 305, and 307 to perform communication is referred to as dual connectivity (DC). When the terminal performs dual access, two configuration schemes are possible.

First, after the terminal performs initial access to the macro base station 301 operating as an LTE / LTE-A system, the upper level signal (system or radio resource control (RRC)) is used for setting information for data transmission and reception for the macro base station. Signal). Thereafter, configuration information for data transmission and reception for the small base station 303, 304, 305 operating as an NR system is received from an upper signal (system or RRC signal) of the macro base station 301, and the small base station 303, 304, By performing random access to 305, the macro base station 301 and the small base station (303, 304, 305) is a dual connection state that can be transmitted and received data.

In this case, the macro base station 301 operating in the LTE / LTE-A system is referred to as a master cell group (MCG), and the small base stations 303, 304, and 305 operating in an NR system are referred to as a secondary cell group (SCG). When the UE is in the dual connection state, the UE uses the evolved-universal mobile communications system (UMTS) terrestrial radio access (E-UTRA) and the MCG using the radio access (or LTE / LTE-A) and the SCG using the NR radio access. It can also be expressed as. Or it may be expressed that the terminal is set to EN-DC (E-UTRA NR Dual Connectivity).

Second, after the UE performs initial access to the small base stations 303, 304, and 305 operating as NR systems, the terminal receives configuration information for data transmission and reception for the small base station from an upper signal (system or RRC signal). . Thereafter, the configuration information for data transmission and reception for the macro base station 301 operating in the LTE / LTE-A system is received from an upper signal (system or RRC signal) of the small base station 303, 304, 305 and the macro base station ( By performing random access to 301, data can be transmitted and received from the small base stations 303, 304, and 305 and the macro base station 301.

At this time, the small base stations 303, 304, and 305 operating in the NR system are referred to as MCG, and the macro base station 301 operating in the LTE system is referred to as SCG. It may be expressed that the terminal is in the dual access state as the terminal is set to MCG using NR radio access and SCG using E-UTRA radio access (or LTE / LTE-A). Or it can be expressed that the terminal is set to NR E-UTRA Dual Connectivity (NE-DC).

Hereinafter, the embodiments described in the present invention will be proposed in consideration of the first dual connectivity configuration and the second dual connectivity configuration. That is, the present invention proposes another embodiment according to whether LTE cells using E-UTRA are MCG or NR cells using NR. The reason is that when the terminal is in a dual access state, importance should be given to uplink transmission to the MCG rather than uplink transmission to the SCG. In addition, timing for transmitting uplink transmission to a cell using NR, for example, PDCCH to PUSCH transmission timing or PDCCH to PUCCH transmission timing may be indicated differently by the higher signal configuration and the indication from the PDCCH. Since the timing for transmitting the transmission, for example, the PDCCH to PUSCH transmission timing or the PDCCH to PUCCH transmission timing is fixed, embodiments of the present invention are proposed in consideration of these conditions.

4 is a diagram illustrating a method of controlling power of uplink transmission according to Embodiments 1 and 2 of the present invention. Embodiments 1 and 2 may be applied when the terminal is set to EN-DC (E-UTRA NR Dual Connectivity).

In Embodiments 1 and 2, the UE transmits P_LTE 402, which is the maximum transmission power for uplink transmission in MCG, P_NR 403, which is the maximum transmission power for uplink transmission in SCG, and maximum in EN-DC. P_total 401, which is the transmission power, is set. In this case, in the case where the sum of the P_LTE 402 and the P_NR 403 is larger than P_total, the first embodiment provides a case in which the UE has a capability for dynamic transmission power distribution.

Example 1

In Embodiment 1 (420), if the UE has the capability to perform dynamic transmission power distribution, the UE may have subframe i 404 for LTE uplink transmission and slot k 406 or k + for NR uplink transmission. When two 407 overlap, the sum of P_LTE 402 and P_NR 403 exceeds P_total 401. In this case, the UE may attach importance to the MCG using E-UTRA radio access (or LTE / LTE-A), and thus may lower transmission power of the SCG using NR. Accordingly, the transmission power for the NR transmission can be reduced (408 or 409) so that the sum of the P_LTE 402 and the P_NR 403 enters the P_total 401.

In the first embodiment, when the terminal has a capability for dynamic transmission power distribution, the terminal transmits the capability signal for the dynamic transmission power distribution to the LTE base station or the NR base station in advance.

Next, in the case where the sum of the P_LTE 402 and the P_NR 403 is larger than the P_total 401, the second embodiment provides a case in which the terminal does not have a capability for dynamic transmission power distribution. .

Example 2

In Embodiment 2 (430), if the terminal does not have a capability to perform dynamic transmission power distribution and thus the capability signal is not transmitted to the base station, the terminal is to determine in which subframes LTE uplink transmission is performed The configuration information is received from the LTE or NR base station via a system or higher level signal. The configuration information may be time division duplex (TDD) configuration information indicating an up-down subframe period, and the configuration information may be received and applied to the LTE cell regardless of whether the LTE cell is TDD or FDD. Upon reception of the configuration information, the UE determines that LTE uplink transmission is performed only in a subframe indicated by an uplink subframe, and does not perform NR uplink transmission in slots capable of NR transmission overlapping with the uplink subframe 405. 410. That is, even if an NR base station configures or schedules NR uplink transmission in slots overlapping with the uplink subframe 405, the UE may not perform the NR transmission.

FIG. 5 is a diagram illustrating a scheme for controlling power of uplink transmission according to Embodiments 3 and 4 of the present invention. Embodiments 3 and 4 may be applied when the terminal is set to NR E-UTRA Dual Connectivity (NE-DC).

In Embodiments 3 and 4, the UE transmits P_LTE 502, which is the maximum transmission power for uplink transmission in SCG, P_NR 503, which is the maximum transmission power for uplink transmission in MCG, and NE-DC according to an upper signal. P_total 501 is set. In this case, in the case where the sum of the P_LTE 502 and the P_NR 503 is larger than the P_total 501, the third embodiment provides a case in which the UE does not have a capability for dynamic transmission power distribution. .

Example 3

In Embodiment 3 (520), if the terminal does not have a capability for dynamic transmission power distribution and thus fails to transmit the capability signal to the base station, the terminal configures in which subframes LTE uplink transmission is performed Information is received from the LTE or NR base station via a system or higher signal. The configuration information may be TDD configuration information indicating a subframe interval up and down, and the configuration information may be received and applied to the LTE cell regardless of whether the LTE cell is TDD or FDD.

In this case, when the UE is set to EN-DC, the UE may perform an operation different from the second embodiment in which the LTE uplink transmission is always performed in the LTE uplink subframe. This is because, when the UE is configured as NE-DC, the UE must first perform NR uplink transmission, which is MCG. Accordingly, even when the UE determines that the LTE uplink transmission is performed in the subframe indicated by the uplink subframe through the reception of the configuration information, the NR uplink instead of the uplink LTE transmission in slots capable of NR transmission overlapping with the uplink subframe 504. Provides a way to perform the transmission.

In Embodiment 3 (520), the UE may receive a PDCCH indicating NR uplink transmission. In this case, the start symbol (that is, subframe i (504) that should transmit the LTE uplink transmission is a value 511 plus the NE-DC processing capability 510 configured to the UE from the last symbol 509 of the PDCCH indicating NR uplink transmission. LTE uplink transmission is dropped before the start symbol).

The NE-DC processing capability 510 configured for the UE may be a symbol number N1 corresponding to the time taken for PDSCH reception for the PDSCH processing capability if the UE receives the PDCCH for scheduling the PDSCH, and has a constant X. It may also be N1 + X. The NE-DC processing capability 510 configured for the UE may be a symbol number N2 corresponding to the time required for preparation of the PUSCH for the PUSCH processing capability, if the UE receives the PDCCH for scheduling the PUSCH. It may also be N2 + Y. Alternatively, for the processing capability required for HARQ-ACK transmission corresponding to the downlink semi-persistent scheduling (SPS) release, the NE-DC processing capability 510 is defined as a value defined as the number of N symbols from the last symbol after receiving the PDCCH. You may.

The number of N symbols may be determined differently according to the subcarrier spacing of the LTE cell or the NR cell. For example, it can be determined as 13 for 15KHz, 15 for 30KHz, 22 for 60KHz, and 25 for 120KHz. Or, conservatively determine, by setting the NE-DC processing capability 510 to a maximum value of N1 or N1 + X, N2 or N2 + Y, N, and whether the terminal drops the LTE uplink transmission using the set value. It can be determined. Before the base station sets the NE-DC processing capability 510 as an upper signal, the terminal transmits the PDSCH processing capability related information or the PUSCH processing capability related information to the base station, and the base station receives the received information from the terminal. In consideration of the processing capability related information of the terminal, the appropriate N1 or N1 + X, N2 or N2 + Y, N value is set to the upper signal, the terminal may receive the configuration.

Next, in the case where the sum of the P_LTE 502 and the P_NR 503 is larger than the P_total 501, the fourth embodiment provides a case in which the UE does not have a capability for dynamic transmission power distribution.

Example 4

In Embodiment 4 (530), if the terminal does not have a capability for dynamic transmission power distribution and thus fails to transmit the capability signal to the base station, the terminal configures in which subframes LTE uplink transmission is performed Information is received from the LTE or NR base station via a system or higher signal. The configuration information may be TDD configuration information indicating a subframe interval up and down, and the configuration information may be received and applied to the LTE cell regardless of whether the LTE cell is TDD or FDD.

In this case, when the UE is set to EN-DC, the UE may perform an operation different from the second embodiment in which the LTE uplink transmission is always performed in the LTE uplink subframe. This is because, when the UE is configured as NE-DC, the UE must first perform NR uplink transmission, which is MCG. Accordingly, even when the UE determines that the uplink transmission is performed in the subframe indicated by the uplink subframe through the reception of the configuration information, the NR uplink instead of the uplink LTE transmission in slots capable of NR transmission overlapping with the uplink subframe 505. Provides a way to perform the transmission.

The UE may receive a PDCCH indicating NR uplink transmission while performing LTE uplink transmission in the subframe 505. At this time, the UE drops the existing LTE transmission (512), and performs NR uplink transmission by the PDCCH indicating NR uplink transmission. Alternatively, when the sum of the last symbol of PDCCH reception and the NE-DC processing capability 510 in the third embodiment is later than the LTE transmission start symbol, LTE uplink transmission is performed and NR uplink transmission is performed by the PDCCH indicating NR uplink transmission. Drop the LTE transmission from the symbol to be performed, and performs the NR transmission.

Although not shown in the present embodiment, as another embodiment, the UE determines that the LTE uplink transmission is performed only in a subframe indicated by an uplink subframe by receiving configuration information on which the LTE uplink transmission is performed. It may be determined that NR uplink transmission is performed among the remaining subframes not indicated by the frame.

FIG. 6 is a diagram illustrating a scheme for controlling power of uplink transmission according to Embodiments 5 and 6 of the present invention. Embodiments 5 and 6 may be applied when the terminal is set to NR E-UTRA Dual Connectivity (NE-DC).

In Embodiments 5 and 6, the UE transmits P_LTE 602, which is the maximum transmit power for uplink transmission in SCG, P_NR 603, which is the maximum transmit power for uplink transmission in MCG, and maximum in NE-DC. P_total 601, which is the transmission power, is set. In this case, in case the sum of the P_LTE 602 and the P_NR 603 is larger than the P_total 601, the fifth embodiment provides a case in which the UE has a capability for dynamic transmission power distribution.

Example 5

In the fifth embodiment 620, when the terminal has the capability to perform dynamic transmission power distribution, the terminal transmits the capability signal for the dynamic transmission power distribution to the LTE base station or the NR base station in advance.

In Embodiment 5 (620), the UE has a capability for dynamic transmission power distribution, and the UE overlaps the subframe i 604 for LTE uplink transmission and the slot k 606 for NR uplink transmission. The sum of P_LTE 602 and P_NR 603 exceeds P_total 601. In this case, the UE may lower the transmission power of the SCG using E-UTRA (or LTE / LTE-A) by attaching importance to the MCG using NR. In this case, when the transmission power of the SCG using E-UTRA needs to be lowered, a problem may occur when the NR uplink transmission timing cannot be predicted due to the flexible timing support of the NR uplink transmission. 5 provides a scheme for lowering the power of LTE uplink considering the processing capability of NR uplink.

In Embodiment 5 (620), the UE may receive a PDCCH indicating NR uplink transmission. In this case, a value 611 obtained by adding the NE-DC processing capability 610 set to the UE from the last symbol 609 of the PDCCH indicating NR uplink transmission is a start symbol (i.e., subframe i Earlier than the start symbol of 604) reduce the transmit power of the LTE uplink transmission (508). In this case, it is possible to reduce the transmit power for LTE uplink transmission such that the sum of the P_LTE 602 and the P_NR 603 is within the P_total 601 (508).

The NE-DC processing capability 610 configured for the UE may be a symbol number N1 corresponding to the time taken for PDSCH reception for the PDSCH processing capability if the UE receives the PDCCH for scheduling the PDSCH, and has a constant X. It may also be N1 + X. The NE-DC processing capability 610 configured for the UE may be the symbol number N2 corresponding to the time taken for PUSCH preparation for the PUSCH processing capability, if the UE receives the PDCCH for scheduling the PUSCH, and may be a constant Y. It may also be N2 + Y. Alternatively, the NE-DC processing capability 610 may be defined by receiving a PDCCH for processing capability required for HARQ-ACK transmission corresponding to a downlink semi-persistent scheduling (SPS) release and defining the number of N symbols from the last symbol. It may be.

The number of N symbols may be determined differently according to the subcarrier spacing of the LTE cell or the NR cell. For example, it can be determined as 13 for 15KHz, 15 for 30KHz, 22 for 60KHz, and 25 for 120KHz. Or conservatively determine the NE-DC processing capability 610 with a maximum value of N1 or N1 + X, N2 or N2 + Y, N and the terminal reduces the power of the LTE uplink transmission using the set value. Can be. Before the base station sets the NE-DC processing capability 610 as a higher signal, the terminal transmits the PDSCH processing capability or PUSCH processing capability related information to the base station, and the base station receives the above processing received from the terminal. In consideration of capability related information, a value of N1 or N1 + X, N2 or N2 + Y, N appropriate to the terminal is set as an upper signal, and the terminal may receive the setting.

Next, in the case where the sum of the P_LTE 602 and the P_NR 603 is larger than the P_total 601, a sixth embodiment will be provided for a case in which the UE has a capability for dynamic transmission power distribution.

Example 6

In the sixth embodiment 630, when the terminal has a capability for dynamic transmission power distribution, the terminal transmits a capability signal for the dynamic transmission power distribution to the LTE base station or the NR base station in advance.

The UE may receive a PDCCH indicating NR uplink transmission while performing LTE uplink transmission in the subframe 605. At this time, the UE drops the LTE transmission that was being performed (612), and performs NR uplink transmission by the PDCCH indicating NR uplink transmission. Alternatively, when the sum of the last symbol of PDCCH reception and the NE-DC processing capability 610 in the fifth embodiment is later than the LTE transmission start symbol, LTE uplink transmission is performed and NR uplink transmission is performed by the PDCCH indicating NR uplink transmission. Drop the LTE transmission from the symbol to be performed, and performs the NR transmission.

The reason for dropping the LTE uplink transmission instead of reducing the power of the LTE uplink transmission in the terminal operation as described above is because it is impossible to change the transmission power in the middle of the subframe in the case of LTE uplink transmission. Therefore, when NR uplink transmission occurs during the LTE uplink transmission as described above, the UE drops the LTE uplink transmission, is indicated to the PDCCH, or performs the NR uplink transmission set by the higher signal.

Example 7

Next, in the case where the sum of the P_LTE 702 and the P_NR 703 is larger than the P_total 701, the seventh embodiment will be provided for a case in which the UE has a capability for dynamic transmission power distribution.

In Embodiment 7, the NE-DC terminal determines another Pcmax for LTE subframes. That is, the terminal receives the configuration of the DL, UL, flexible, reserved slots for the slots from the NR base station from the upper signal (system information, or RRC signal), so that uplink transmission for the NR in the UL slot or flexible slot Determining that this may occur, the LTE subframe 704 overlapping even in one OFDM symbol with the UL slot or flexible slot 720 where NR uplink may occur, and the DL slot or reserved slot where NR uplink cannot occur Pcmax is determined for the LTE subframe 705 that overlaps with 730, respectively.

For LTE subframe 704, Pcmax, the maximum value of LTE transmit power, is determined to be less than or equal to p_LTE * r (710), and Pcmax, the maximum value of LTE transmit power, is p_LTE for LTE subframe 705. The value is determined to be less than or equal to 711. The p_LTE and p_NR may be received by the terminal from an upper signal transmitted from the LTE base station or the NR base station, and r may be set to values for each LTE subframe with a value less than or equal to 1, and the LTE base station or The terminal may receive from an upper signal transmitted from the NR base station.

When NR uplink transmission occurs in the LTE subframe 704, the UE may set Pcmax of NR to a value less than or equal to min (p_NR, P_total-p_lte_actual) in order to allocate transmission power (P_NR) of NR. have. In the LTE subframe 704, the UE allocates P_LTE less than or equal to the LTE Pcmax 710 for LTE uplink transmission. In the seventh embodiment, p_lte_actual 712 is allocated to perform LTE uplink transmission.

In the subframe 705, it may be assumed that there is no NR uplink transmission, so that the UE allocates P_LTE less than or equal to the LTE Pcmax 711 for the LTE uplink transmission and performs LTE uplink transmission.

In another embodiment, even if the above-described embodiment 7 is applied, the UE may control the downlink control channel and NE uplink transmission even if the NE-DC processing capability is set by the RRC, even if the NR UL slot or the flexible slot. When the slots are slots for which NR UL cannot be transmitted due to DC processing capability, there is no need to limit the LTE transmit power in the LTE uplink subframe overlapping the NR slots. Accordingly, in the above case, the NE-DC terminal may determine Pcmax to be less than or equal to p_LTE and determine P_LTE in the LTE uplink subframe. Alternatively, r set from the NR base station or the LTE base station may be determined as 1, and P_LTE may be determined.

The NE-DC processing capability configured for the UE may be a symbol number N1 corresponding to the time taken for PDSCH reception for the PDSCH processing capability if the UE receives the PDCCH for scheduling the PDSCH, and N1 + plus a constant X. It may be X. The NE-DC processing capability configured for the UE may be the symbol number N2 corresponding to the time taken for PUSCH preparation for the PUSCH processing capability if the UE receives the PDCCH for scheduling the PUSCH, and N2 + plus a constant Y. It may be Y. Alternatively, the NE-DC processing capability may be defined by receiving a PDCCH for processing capability required for HARQ-ACK transmission corresponding to a downward semi-persistent scheduling (SPS) release and defining the number of N symbols from the last symbol. Alternatively, the constant value may be determined according to the subcarrier spacing of the NR cell.

The number of N symbols may be determined differently according to the subcarrier spacing of the LTE cell or the NR cell. For example, it can be determined as 13 for 15KHz, 15 for 30KHz, 22 for 60KHz, and 25 for 120KHz. Alternatively, to determine conservatively, the NE-DC processing capability is set to the maximum or minimum value of N1 or N1 + X, N2 or N2 + Y, N, and the terminal reduces the power of LTE uplink transmission by using the set value. Can be. Before the base station sets the NE-DC processing capability to the terminal as a higher signal, the terminal transmits the PDSCH processing capability or PUSCH processing capability related information to the base station, and the base station receives the processing capability received from the terminal. In consideration of the related information, an appropriate N1 or N1 + X, N2 or N2 + Y, N value is set as an upper signal to the terminal, and the terminal may receive the setting.

Example 8

Next, in the case where the sum of the P_LTE 802 and the P_NR 803 is larger than the P_total 801, an eighth embodiment will be provided for a case in which the UE has a capability for dynamic transmission power distribution.

In Embodiment 8, the NE-DC terminal determines another Pcmax for LTE subframes. That is, the terminal receives the configuration of the DL, UL, flexible, reserved slots from the NR base station from the upper signal (system information or RRC signal), and the uplink transmission for the NR may occur in the UL slot or flexible slot It is determined that the UL subframe 804 overlapping the UL slot or flexible slot 820, which may occur in NR uplink transmission, in one OFDM symbol, and the DL slot or reserved slot 830, in which NR uplink transmission does not occur. Pcmax is determined for LTE subframe 805, respectively.

For the LTE subframe 804, Pcmax, the maximum value of the LTE transmit power, is determined to be less than or equal to p_LTE (810), and for the LTE subframe 805, the Pcmax, the maximum value of the LTE transmit power, is determined. (811). The p_LTE and p_NR may be received by the terminal from an upper signal transmitted from the LTE base station or the NR base station.

When NR uplink transmission occurs in the LTE subframe 804, the UE may set Pcmax of the NR to a value less than or equal to min (p_NR, P_total-p_lte_actual) in order to allocate the transmission power (P_NR) of the NR. In the LTE subframe 804, the UE allocates P_LTE less than or equal to the LTE Pcmax 810 for LTE uplink transmission. In the eighth embodiment, p_lte_actual 812 is allocated to perform LTE uplink transmission. In the subframe 805, it may be assumed that there is no NR uplink transmission, so that the UE allocates P_LTE less than or equal to the LTE Pcmax 811 for LTE uplink transmission to perform LTE uplink transmission.

In another embodiment, even if the NE-DC processing capability is set by the RRC, even if the NE-DC processing capability is set by the RRC, the UE may control the downlink control channel indicating the uplink transmission of the NR and the NE even if the NE UL slot or the flexible slot is used. When the slots are slots for which NR UL cannot be transmitted due to DC processing capability, there is no need to limit the LTE transmit power in the LTE uplink subframe overlapping the NR slots. Accordingly, in such a case, the NE-DC terminal may determine to maintain Pcmax in the LTE uplink subframe and determine P_LTE.

The NE-DC processing capability configured for the UE may be a symbol number N1 corresponding to the time taken for PDSCH reception for the PDSCH processing capability if the UE receives the PDCCH for scheduling the PDSCH, and N1 + plus a constant X. It may be X. The NE-DC processing capability configured for the UE may be the symbol number N2 corresponding to the time taken for PUSCH preparation for the PUSCH processing capability if the UE receives the PDCCH for scheduling the PUSCH, and N2 + plus a constant Y. It may be Y. Alternatively, the NE-DC processing capability may be defined by receiving a PDCCH for processing capability required for HARQ-ACK transmission corresponding to a downward semi-persistent scheduling (SPS) release and defining the number of N symbols from the last symbol. Alternatively, the constant value may be determined according to the subcarrier spacing of the NR cell.

The number of N symbols may be determined differently according to the subcarrier spacing of the LTE cell or the NR cell. For example, it can be determined as 13 for 15KHz, 15 for 30KHz, 22 for 60KHz, and 25 for 120KHz. Alternatively, to determine conservatively, the NE-DC processing capability is set to the maximum or minimum value of N1 or N1 + X, N2 or N2 + Y, N, and the terminal reduces the power of LTE uplink transmission by using the set value. Can be. Before the base station sets the NE-DC processing capability to the terminal as a higher signal, the terminal transmits the PDSCH processing capability or PUSCH processing capability related information to the base station, and the base station receives the processing capability received from the terminal. In consideration of the related information, an appropriate N1 or N1 + X, N2 or N2 + Y, N value is set as an upper signal to the terminal, and the terminal may receive the setting.

Example 9

Next, in the case where the sum of the P_LTE 902 and the P_NR 903 is larger than the P_total 901, the ninth embodiment will be provided for the case in which the UE has a capability for dynamic transmission power distribution.

In Embodiment 9, the NE-DC terminal maintains Pcmax for LTE subframes. That is, the terminal determines to apply Pcmax, the maximum value of the LTE transmit power, to all the LTE subframes 904 and 905 (910). The p_LTE and p_NR may be received by the terminal from an upper signal transmitted from the LTE base station or the NR base station. When NR uplink transmission occurs in the LTE subframe 904, the UE may set Pcmax of the NR to a value less than or equal to min (p_NR, P_total-p_lte_actual) to allocate the transmission power (P_NR) of the NR.

In the LTE subframes 904 and 905, the UE allocates P_LTE less than or equal to the LTE Pcmax 910 for LTE uplink transmission. In the ninth embodiment, p_lte_actual 912 is allocated to perform LTE uplink transmission. Therefore, in the ninth embodiment, the LTE Pcmax 910 must be conservatively determined regardless of whether NR uplink transmission occurs, and even when there is no NR transmission, the LTE transmission power can only be limited lower.

In another embodiment, even when the UE applies the ninth embodiment, when the NE-DC processing capability is set by the RRC, the UE controls the downlink control channel indicating NR uplink transmission and the NE-DC processing capability. If the slots are slots for which NR UL cannot be transmitted, there is no need to limit the LTE transmit power in the LTE uplink subframe that overlaps the NR slots. Therefore, in such a case, the NE-DC terminal may determine to maintain Pcmax in the LTE uplink subframe and determine P_LTE.

The NE-DC processing capability configured for the UE may be a symbol number N1 corresponding to the time taken for PDSCH reception for the PDSCH processing capability if the UE receives the PDCCH for scheduling the PDSCH, and N1 + plus a constant X. It may be X. The NE-DC processing capability configured for the UE may be the symbol number N2 corresponding to the time taken for PUSCH preparation for the PUSCH processing capability if the UE receives the PDCCH for scheduling the PUSCH, and N2 + plus a constant Y. It may be Y. Alternatively, the NE-DC processing capability may be defined by receiving a PDCCH for processing capability required for HARQ-ACK transmission corresponding to a downlink semi-persistent scheduling (SPS) release and defining the number of N symbols from the last symbol. Alternatively, the constant value may be determined according to the subcarrier spacing of the NR cell.

The number of N symbols may be determined differently according to the subcarrier spacing of the LTE cell or the NR cell. For example, it can be determined as 13 for 15KHz, 15 for 30KHz, 22 for 60KHz, and 25 for 120KHz. Alternatively, the NE-DC processing capability may be set to a maximum value or a minimum value of N1 or N1 + X, N2 or N2 + Y, and N may be determined conservatively, and the terminal may reduce power of LTE uplink transmission by using the set value. have. Before the base station sets the NE-DC processing capability to the terminal as a higher signal, the terminal transmits the PDSCH processing capability or PUSCH processing capability related information to the base station, and the base station receives the processing capability received from the terminal. In consideration of the related information, an appropriate N1 or N1 + X, N2 or N2 + Y, N value is set as an upper signal to the terminal, and the terminal may receive the setting.

In all the above embodiments, for the case where the sum of P_LTE and P_NR is smaller than P_total, the UE may perform LTE uplink transmission by applying the P_LTE and perform NR uplink transmission by applying the P_NR.

10 is a diagram illustrating a base station and a terminal procedure according to the embodiments proposed by the present invention.

First, the base station procedure will be described.

In step 1011, the base station transmits configuration information of each cell to the terminal through the system information or higher signal. The configuration information may be cell-related information (TDD or FDD information, up-down carrier frequency, up-down frequency band, up-down subcarrier spacing, etc.) of MCG or SCG cells required for dual access, and required for data transmission and reception in the MCG or SCG. It may be setting information. Or it may be configuration information related to the NE-DC processing capability described in the embodiments of the present invention. The base station may be an NR base station using NR radio access or an E-UTRA base station using E-UTRA radio access.

In step 1012, the base station sets uplink transmission to the terminal and transmits scheduling information indicating uplink transmission according to the embodiments proposed by the present invention. The base station may be an NR base station using NR radio access or an E-UTRA base station using E-UTRA radio access. The uplink transmission configuration may mean uplink transmission in which transmission is configured by higher signal configuration instead of PDCCH like periodic channel information transmission, and uplink transmission indicated by the scheduling information is PUSCH transmission or HARQ-ACK. Like transmission, this may mean uplink transmission indicated by the PDCCH and transmitted from the UE.

In step 1013, the base station receives uplink transmission from the terminal according to the embodiments proposed by the present invention. The base station may be an NR base station using NR radio access or an E-UTRA base station using E-UTRA radio access.

Next, the terminal procedure will be described.

In step 1021, the terminal receives configuration information of each cell from the base station through system information or higher signal. The configuration information may be cell-related information (TDD or FDD information, up-down carrier frequency, up-down frequency band, up-down subcarrier spacing, etc.) of MCG or SCG cells required for dual access, and required for data transmission and reception in the MCG or SCG. It may be setting information. Or it may be configuration information related to the NE-DC processing capability described in the embodiments of the present invention. As described in the embodiments of the present invention, the terminal may transmit PDSCH processing capability or PUSCH processing capability related information to the base station before receiving the NE-DC processing capability as a higher signal from the base station. The base station may be an NR base station using NR radio access or an E-UTRA base station using E-UTRA radio access.

In step 1022, the terminal receives uplink transmission configuration information from the base station according to the embodiments proposed by the present invention, and receives scheduling information indicating uplink transmission. The base station may be an NR base station using NR radio access or an E-UTRA base station using E-UTRA radio access. The uplink transmission configuration information may refer to configuration information related to uplink transmission in which transmission is configured by higher signal configuration instead of PDCCH like periodic channel information transmission. Uplink transmission indicated by the scheduling information is a PUSCH. Like transmission or HARQ-ACK transmission, it may mean uplink transmission indicated by the PDCCH and transmitted from the terminal.

In step 1023, the terminal transmits uplink transmission to the base station by controlling the transmission power according to the embodiments proposed by the present invention. Controlling the transmit power may include dropping uplink transmissions of low importance or reducing uplink transmission power as described in the embodiments of the present invention. The base station may be an NR base station using NR radio access or an E-UTRA base station using E-UTRA radio access.

11 is a diagram illustrating a base station apparatus according to embodiments proposed by the present invention.

The controller 1101 sets necessary information according to the base station procedure according to FIG. 7 of the present invention and embodiments of the present invention, and controls uplink transmission from the terminal according to the present invention, thereby transmitting LTE or 5G control information. 1105 and the 5G data transmission and reception device 1107, and transmits the LTE or 5G data with the terminal through the LTE or 5G data transmission and reception device 1107 by scheduling the LTE or 5G data in the scheduler 1103. . In the present base station apparatus, LTE and 5G are described together for convenience, but the base station apparatus may be an NR base station using NR radio access or an E-UTRA base station using E-UTRA radio access.

12 is a diagram illustrating a terminal device according to the present invention.

Receiving necessary configuration information and scheduling according to the terminal procedure according to FIG. 10 of the present invention and embodiments of the present invention from the base station, and controlling uplink transmission power according to the present invention to be configured from the base station or indicated by scheduling Do this. Receive an uplink data channel transmission resource position from the base station through the LTE or 5G control information receiving device 1205 and LTE or 5G data transmission and reception device 1206 or multiplexes the uplink control information to the uplink data channel, the controller 1201 receives The LTE or 5G data scheduled at the resource location is transmitted and received with the LTE or 5G base station via the LTE or 5G data transceiver 1206. In this figure, the LTE and 5G devices are described as if for convenience, but devices for LTE or 5G may be configured separately. The base station for transmitting and receiving the control information and data may be an NR base station using NR radio access, or may be an E-UTRA base station using E-UTRA radio access.

In addition, the embodiments disclosed in the specification and the drawings merely present specific examples to easily explain and easily understand the contents of the present invention, and are not intended to limit the scope of the present invention. Therefore, the scope of the present invention should be construed that all changes or modifications derived based on the technical spirit of the present invention are included in the scope of the present invention in addition to the embodiments disclosed herein.

Claims (15)

1. In a wireless communication system, a terminal method for performing dual connectivity with a first base station based on a first radio access technology and a second base station based on a second radio access technology,

   Receiving a downlink signal from the first base station;

   Checking whether a transmission timing of a first uplink signal corresponding to the downlink signal overlaps with a transmission timing of a second uplink signal to the second base station;

   When the transmission timing of the first uplink signal and the transmission timing of the second uplink signal overlap, the sum of the first transmission power for the first uplink transmission and the second transmission power for the second uplink transmission is Checking whether the maximum transmission power of the terminal is exceeded; And

   If the sum of the first transmit power and the second transmit power exceeds the maximum transmit power of the terminal, the second transmit power is controlled based on a processing time for transmitting the first uplink signal. Terminal method characterized in that it comprises a step.
2. The method of claim 1,

   The processing time is

   If the downlink signal is a physical downlink control channel (PDCCH), includes a time for receiving a physical downlink shared channel (PDSCH) scheduled by the PDCCH or a preparation time for transmission of a physical uplink shared channel (PUSCH),

   And if the downlink signal is a PDSCH, a preparation time for transmitting a hybrid automatic repeat and request (HARQ) acknowledgment / negative ack (HACK) corresponding to the received PDSCH.
3. The method of claim 1,

   Controlling the second transmission power,

   And decreasing the maximum transmission power set for the second base station to a predetermined transmission power value.
4. The method of claim 3,

   Receiving the predetermined transmission power value from the first base station,

   The first radio access technology is NR (new radio),

   The second radio access technology is a terminal method, characterized in that e-UTRA (evolved-universal mobile communication system (UMTS) terrestrial radio access).
5. In a wireless communication system, a first base station method that is based on a first radio access technology, and supports dual connectivity for a terminal with a second base station based on a second radio access technology,

   Transmitting a downlink signal to the terminal; And

   Receiving, from the terminal, a first uplink signal corresponding to the downlink signal based on a first transmission power;

   The second transmission power for the transmission of the second uplink signal from the terminal to the second base station, the transmission timing of the first uplink signal overlaps with the transmission timing of the second uplink signal, the first transmission A first base station controlled by the terminal based on the first uplink signal processing time of the terminal when a sum of power and the second transmit power exceeds a maximum transmit power of the terminal; Way.
6. The method of claim 5,

   The processing time of the terminal,

   If the downlink signal is a physical downlink control channel (PDCCH), includes a time for receiving a physical downlink shared channel (PDSCH) scheduled by the PDCCH or a preparation time for transmission of a physical uplink shared channel (PUSCH),

   And if the downlink signal is a PDSCH, a preparation time for transmitting a hybrid automatic repeat and request (HARQ) acknowledgment / negative ack (ACK / NACK) corresponding to the received PDSCH.
7. The method of claim 5,

   The second transmission power is controlled by setting the maximum transmission power for the second base station set in the terminal to a low value at a predetermined transmission power value.
8. The method of claim 7, wherein

   Transmitting the preset transmission power value to the terminal;

   The first radio access technology is NR (new radio),

   The second radio access technology is an evolved-universal mobile communication system (UMTS) terrestrial radio access (E-UTRA).
9. In a wireless communication system, a terminal for performing dual connectivity with a first base station based on a first radio access technology and a second base station based on a second radio access technology,

   A transceiver; And

   The transceiver is controlled to receive a downlink signal from the first base station, and a transmission timing of a first uplink signal corresponding to the downlink signal overlaps with a transmission timing of a second uplink signal to the second base station. If the transmission timing of the first uplink signal and the transmission timing of the second uplink signal overlap, the transmission of the first transmission power for transmitting the first uplink signal and the transmission of the second uplink signal are performed. Determine whether the sum of the second transmission power exceeds the maximum transmission power of the terminal, and when the sum of the first transmission power and the second transmission power exceeds the maximum transmission power of the terminal, the first uplink signal And a controller for controlling the second transmission power based on a processing time for transmission of the.
10. The method of claim 9,

    The processing time is

    If the downlink signal is a physical downlink control channel (PDCCH), includes a time for receiving a physical downlink shared channel (PDSCH) scheduled by the PDCCH or a preparation time for transmission of a physical uplink shared channel (PUSCH),

    And if the downlink signal is a PDSCH, a UE comprising a preparation time for transmission of a hybrid automatic repeat and request (HARQ) acknowledgment / negative ack (HACK) corresponding to the received PDSCH.
11. The method of claim 9, wherein the control unit,

    And reducing the maximum transmit power set for the second base station to a preset transmit power value and controlling the second transmit power based on the preset transmit power value.
12. The method of claim 11,

    The controller controls the transceiver to receive the preset transmission power value from the first base station,

    The first radio access technology is NR (new radio),

    The second radio access technology, the terminal characterized in that the evolved-universal mobile communication system (UMTS) terrestrial radio access (E-UTRA).
13. In a wireless communication system, a first base station that is based on a first radio access technology, and supports dual connectivity for a terminal with a second base station based on a second radio access technology,

    A transceiver; And

    A control unit which transmits a downlink signal to the terminal and controls the transceiver to receive a first uplink signal corresponding to the downlink signal based on a first transmission power from the terminal;

    The second transmission power for the transmission of the second uplink signal from the terminal to the second base station, the transmission timing of the first uplink signal overlaps with the transmission timing of the second uplink signal, the first transmission A first base station controlled by the terminal based on the first uplink signal processing time of the terminal when the sum of the power and the second transmit power exceeds the maximum transmit power of the terminal; .
14. The method of claim 13,

    The processing time of the terminal,

    If the downlink signal is a physical downlink control channel (PDCCH), includes a time for receiving a physical downlink shared channel (PDSCH) scheduled by the PDCCH or a preparation time for transmission of a physical uplink shared channel (PUSCH),

    If the downlink signal is a PDSCH, the first base station comprising a preparation time for transmission of a hybrid automatic repeat and request (HARQ) acknowledgment / negative acknowledgment (ACK / NACK) corresponding to the received PDSCH.
15. The method of claim 13,

    The controller controls the transceiver to transmit the preset transmission power value to the terminal.

    The second transmit power is controlled by setting the maximum transmit power for the second base station set in the terminal to a low value at a preset transmit power value.

    The first radio access technology is NR (new radio),

    The second radio access technology is a first base station, characterized in that the evolved-universal mobile communication system (UMTS) terrestrial radio access (E-UTRA).

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