WO2019078593A1

WO2019078593A1 - Method and device for supporting beam-based cooperative communication in wireless communication system

Info

Publication number: WO2019078593A1
Application number: PCT/KR2018/012218
Authority: WO
Inventors: 곽영우; 노훈동; 신철규
Original assignee: 삼성전자 주식회사
Priority date: 2017-10-17
Filing date: 2018-10-17
Publication date: 2019-04-25

Abstract

Disclosed are a method and a device for supporting beam-based cooperative communication for smoothly providing a service in a wireless communication system, and a method by which a terminal supports beam-based cooperative communication, according to one embodiment, comprises the steps of: receiving, from a base station, configuration information for measuring the quality of a beam; receiving first reference signals for respective favorite channels corresponding to a plurality of transmission beams received from the base station and second reference signals for respective interference channels corresponding to a plurality of transmission beams acting as interference between the plurality of transmission beams received from the base station; and measuring beam quality for the plurality of transmission beams received from the base station on the basis of the configuration information, the first reference signals and the second reference signals.

Description

Method and apparatus for supporting beam-based cooperative communication in a wireless communication system

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to wireless communication systems, and more particularly, to a method and apparatus for supporting beam-based cooperative communication to smoothly provide services in a wireless communication system.

Efforts are underway to develop an improved 5G or pre-5G communication system to meet the growing demand for wireless data traffic after commercialization of the 4G communication system. For this reason, a 5G communication system or a pre-5G communication system is called a system after a 4G network (Beyond 4G network) communication system or after a LTE system (Post LTE). To achieve a high data rate, a 5G communication system is being considered for implementation in a very high frequency (mmWave) band (e.g., a 60 Gigahertz (70GHz) band). In order to mitigate the path loss of the radio wave in the very high frequency band and to increase the propagation distance of the radio wave, in the 5G communication system, beamforming, massive MIMO, full-dimension MIMO (FD-MIMO ), Array antennas, analog beam-forming, and large scale antenna technologies are being discussed. In order to improve the network of the system, the 5G communication system has developed an advanced small cell, an advanced small cell, a cloud radio access network (cloud RAN), an ultra-dense network, (D2D), a wireless backhaul, a moving network, cooperative communication, Coordinated Multi-Points (CoMP), and interference cancellation Have been developed. In addition, in the 5G system, the Advanced Coding Modulation (ACM) scheme, Hybrid FSK and QAM Modulation (FQAM) and Sliding Window Superposition Coding (SWSC), the advanced connection technology, Filter Bank Multi Carrier (FBMC) (non-orthogonal multiple access), and SCMA (sparse code multiple access).

On the other hand, the Internet is evolving into an Internet of Things (IoT) network in which information is exchanged between distributed components such as objects in a human-centered connection network where humans generate and consume information. IoE (Internet of Everything) technology, which combines IoT technology with big data processing technology through connection with cloud servers, is also emerging. In order to implement IoT, technology elements such as sensing technology, wired / wireless communication, network infrastructure, service interface technology, and security technology are required. In recent years, sensor network for connecting objects, Machine to Machine , M2M), and MTC (Machine Type Communication). In the IoT environment, an intelligent IT (Internet Technology) service can be provided that collects and analyzes 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 appliance, and advanced medical service through fusion of existing information technology . &Lt; / RTI >

Accordingly, various attempts have been made to apply the 5G communication system to the IoT network. For example, technologies such as a sensor network, a machine to machine (M2M), and a machine type communication (MTC) are implemented by techniques such as beam forming, MIMO, and array antennas, which are 5G communication technologies . The application of the cloud radio access network (cloud RAN) as the big data processing technology described above is an example of the convergence of 3eG technology and IoT technology.

As described above, various services can be provided according to the development of a wireless communication system, and thus a method for smoothly providing such services is required.

The disclosed embodiments can provide a method and apparatus for supporting beam-based collaborative communication to smoothly provide services in a wireless communication system.

A method of supporting beam-based cooperative communication of a terminal according to an exemplary embodiment includes receiving configuration information for measuring quality of a beam from a base station; The first reference signals for the respective preferred channels corresponding to the plurality of transmission beams received from the base station and the respective interference channels corresponding to the plurality of transmission beams serving as interference to the plurality of transmission beams received from the base station Receiving second reference signals; And measuring a quality of a beam for a plurality of transmission beams received from the base station based on the setting information, the first reference signals, and the second reference signals.

A method of supporting beam-based cooperative communication of a base station according to an exemplary embodiment includes transmitting configuration information for beam quality measurement to a terminal; Transmitting reference signals to the terminal using a plurality of transmission beams; And receiving feedback information on the reference signals from the terminal.

A terminal supporting beam-based collaborative communication according to an exemplary embodiment includes a transmitting / receiving unit; At least one memory for storing a program for supporting beam-based collaborative communication; And receiving the setting information for measuring the quality of the beam from the base station by executing the program and generating first reference signals for each of the preferred channels corresponding to the plurality of transmission beams received from the base station, Receiving second reference signals for each interference channel corresponding to a plurality of transmission beams serving as interference to a plurality of transmission beams, And at least one processor for measuring the quality of the beam for the plurality of transmission beams received from the base station.

A base station supporting beam-based collaborative communication according to an exemplary embodiment, the base station comprising: a transceiver; At least one memory for storing a program for supporting beam-based collaborative communication; And at least one processor for transmitting setting information for measuring quality of a beam to a terminal, transmitting reference signals to the terminal using a plurality of transmission beams, and receiving feedback information about the reference signals from the terminal .

According to the present disclosure, a service can be smoothly provided in a wireless communication system.

1 is a diagram illustrating the configuration of a time-frequency domain, which is a downlink radio resource region of LTE, LTE-A or similar system.

2 is a cross-

Lt; / RTI > and < RTI ID = 0.0 > wCQI < / RTI >

3,

The timing of feedback of RI, sCQI and wCQI for the case of Fig.

Figures 4 and 5 show

The case of PTI = 0 and the case of PTI = 0, respectively.

FIG. 6 is a diagram for explaining periodic channel status reporting supported by terminals having CSI-RS of 12 ports or more in LTE, LTE-A or similar system.

FIG. 7 is a diagram illustrating a method in which data of eMBB, URLLC, and mMTC, which are services considered in a 5G or NR system, are allocated in radio resources.

8 is a diagram for explaining a method of transmitting a synchronization signal considered in a 5G or NR system.

9 is a diagram for explaining a method of transmitting a PBCH considered in a 5G or NR system.

10 is a diagram for explaining how each service is multiplexed in a 5G or NR system.

FIG. 11 is a diagram for explaining resource setting, channel measurement setting, and channel status report setting necessary to support channel status reporting in a 5G or 5G or NR system.

12 is a diagram for explaining a method of triggering a link in a trigger measurement setting according to an aperiodic channel state report trigger method 1 in a 5G or NR system.

FIG. 13 is a diagram for explaining an instruction sequence of a bitmap for an aperiodic channel state report trigger method 1 in a 5G or NR system.

14 is a diagram for explaining a method of triggering a channel status report setting in a trigger measurement setting according to an aperiodic channel status report trigger method 2 in a 5G or NR system.

15 is a diagram for explaining an instruction sequence of a bitmap for an aperiodic channel state report trigger method 2 in a 5G or NR system.

16 is a diagram for explaining a method of indirectly indicating an aperiodic CSI-RS using an aperiodic channel status report indication field in a 5G or NR system.

17 is a diagram illustrating a hybrid beamforming structure according to an embodiment.

18 and 19 are views for explaining a beam sweeping operation of a base station and a terminal according to an embodiment.

20 is a diagram illustrating reference signal transmission for beam selection of a base station or a terminal according to an exemplary embodiment of the present invention.

FIG. 21 is a view for explaining beam management in a connection cell (downlink) according to one embodiment and beam management in consideration of other cells in the vicinity.

FIG. 22 is a view for explaining beam management in an uplink and beam management in consideration of neighboring cells according to an embodiment.

23 is a view for explaining beam management in a cross-link and beam management in consideration of other cells in the vicinity according to an embodiment.

24 is a view for explaining a method of beam-based quality measurement according to an embodiment.

25 is a diagram for explaining a method of transmitting a reference signal transmission time point for measuring a preferred channel and an interference channel reference signal according to an embodiment at the same time.

26 is a diagram illustrating an operation of the UE when the number of interference channels according to an exemplary embodiment is smaller than the number of preferred channels.

FIG. 27 is a view for explaining a method of allowing a reference signal transmission time point for measurement of a preferred channel and an interference channel reference signal according to an embodiment to be transmitted at another time point.

FIG. 28 is a diagram for describing measurement and reporting for beam cooperation of a terminal based on another time point transmission according to an exemplary embodiment. FIG.

29 is a flowchart illustrating an operation of a terminal according to an embodiment.

30 is a flowchart illustrating an operation of a base station according to an embodiment of the present invention.

31 is a block diagram showing an internal structure of a terminal according to an embodiment

32 is a block diagram illustrating an internal structure of a base station according to an embodiment.

A method of supporting beam-based cooperative communication of a terminal according to an exemplary embodiment includes receiving configuration information for measuring quality of a beam from a base station, receiving first configuration information for each preferred channel corresponding to a plurality of transmission beams received from the base station, Receiving second reference signals for each interfering channel corresponding to a plurality of transmission beams serving as interference to reference beams and a plurality of transmission beams from the base station, And measuring the quality of the beam for a plurality of transmission beams received from the base station based on the second reference signals.

In one embodiment, measuring the quality of a beam for a plurality of transmit beams received from the base station may include measuring a beam quality of the beam based on a ratio of a receive intensity of the first reference signals to a receive intensity of the second reference signals, And measuring the quality.

In one embodiment, the receiving of the first reference signals and the second reference signals may receive the first reference signals and the second reference signals at the same time.

In one embodiment, measuring the quality of a beam for a plurality of transmission beams received from the base station may include: determining a reception intensity of only a received signal if the first reference signals are different from the second reference signals, Measuring the quality of the beam as a basis, measuring the quality of the beam, ignoring some reference signals that are not received, or measuring the quality of the beam based on a larger number of reference signals .

In one embodiment, in the step of receiving the first reference signals and the second reference signals, the first reference signals and the second reference signals are received at different time points, and a plurality of Measuring the quality of the beam with respect to the transmission beam may include measuring a reception intensity of the first reference signals and a reception intensity of the second reference signals received at the different time points, respectively, And measuring a quality of a beam for a plurality of transmission beams received from the base station.

In one embodiment, the receiving of the first reference signals and the second reference signals may include receiving the first reference signals and the second reference signals at the different time points, .

In one embodiment, the method further includes receiving feedback setting information from the base station, generating feedback information based on the measured beam quality and the feedback setting information, and transmitting the feedback information to the base station can do.

A method of supporting beam-based cooperative communication of a base station according to an exemplary embodiment includes transmitting configuration information for beam quality measurement to a terminal, transmitting reference signals to the terminal using a plurality of transmission beams, And receiving feedback information on the reference signals.

In one embodiment, the method further comprises transmitting feedback setting information to the terminal, wherein receiving feedback information on the reference signal from the terminal includes receiving the feedback information based on the feedback setting information . &Lt; / RTI >

In one embodiment, the base station may further include transmitting and receiving transmission beam related information to and from a base station that transmits a transmission beam serving as interference with respect to the plurality of transmission beams transmitted by the base station.

A terminal supporting beam-based collaborative communication according to an exemplary embodiment includes at least one or more memories for storing a program for supporting a transmitting / receiving unit, a beam-based cooperative communication, and a setting for measuring quality of a beam from a base station Corresponding to a plurality of transmission beams serving as interference with first reference signals for each of the plurality of transmission channels corresponding to the plurality of transmission beams received from the base station and a plurality of transmission beams received from the base station, Receiving second reference signals for each interference channel and measuring a quality of a beam for a plurality of transmission beams received from the base station based on the setting information, the first reference signals, and the second reference signals And at least one processor.

In one embodiment, the at least one processor may measure the quality of the beam based on a ratio of a reception intensity of the first reference signals to a reception intensity of the second reference signals.

In one embodiment, the at least one processor may receive the first reference signals and the second reference signals at the same time.

In one embodiment, the at least one processor measures the quality of the beam based on the reception intensity of only a received signal when the first reference signals and the second reference signals are different, The quality of the beam can be measured by ignoring some reference signals or based on a larger number of reference signals.

In one embodiment, the at least one processor is configured to receive the first reference signals and the second reference signals at different points in time, and adjust the reception intensity of the first reference signals received at the different points in time, 2 reference signals, respectively, and measure the beam quality of a plurality of transmission beams received from the base station by combining the measured reception strengths.

In one embodiment, the at least one processor may receive the first reference signals and the second reference signals received at the different time points using the same reception beam.

In one embodiment, the at least one processor may generate feedback information based on the measured beam quality and the feedback setting information, and may transmit the feedback information to the base station.

In one embodiment, the at least one processor may transmit feedback setting information to the terminal and receive the feedback information based on the feedback setting information.

In one embodiment, the at least one processor may further comprise transmitting and receiving transmission beam related information with a base station transmitting a transmission beam serving as interference for the plurality of transmission beams transmitted by the base station.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

In the following description of the embodiments of the present invention, descriptions of techniques which are well known in the technical field of the present invention and are not directly related to the present invention will be omitted. This is for the sake of clarity of the present invention without omitting the unnecessary explanation.

For the same reason, some of the elements in the accompanying drawings are exaggerated, omitted or schematically shown. Also, the size of each component does not entirely reflect the actual size. In the drawings, the same or corresponding components are denoted by the same reference numerals.

BRIEF DESCRIPTION OF THE DRAWINGS The advantages and features of the present invention and the manner of achieving them will become apparent with reference to the embodiments described in detail below with reference to the accompanying drawings. The present invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art. To fully disclose the scope of the invention to those skilled in the art, and the invention is only defined by the scope of the claims. Like reference numerals refer to like elements throughout the specification.

It will be appreciated that the combinations of blocks and flowchart illustrations in the process flow diagrams may be performed by computer program instructions. These computer program instructions may be loaded into a processor of a general purpose computer, special purpose computer, or other programmable data processing apparatus, so that those instructions, which are executed through a processor of a computer or other programmable data processing apparatus, Thereby creating means for performing functions. These computer program instructions may also be stored in a computer usable or computer readable memory capable of directing a computer or other programmable data processing apparatus to implement the functionality in a particular manner so that the computer usable or computer readable memory The instructions stored in the block diagram (s) are also capable of producing manufacturing items containing instruction means for performing the functions described in the flowchart block (s). Computer program instructions may also be stored on a computer or other programmable data processing equipment so that a series of operating steps may be performed on a computer or other programmable data processing equipment to create a computer- It is also possible for the instructions to perform the processing equipment to provide steps for executing the functions described in the flowchart block (s).

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

Herein, the term " part " used in the present embodiment means a hardware component such as software or an FPGA (Field Programmable Gate Array) or ASIC (Application Specific Integrated Circuit) do. However, 'part' is not meant to be limited to software or hardware. &Quot; to " may be configured to reside on an addressable storage medium and may be configured to play one or more processors. Thus, by way of example, 'parts' may refer to components such as software components, object-oriented software components, class components and task components, and processes, functions, , Subroutines, segments of program code, drivers, firmware, microcode, circuitry, data, databases, data structures, tables, arrays, and variables. The functions provided within the components and components may be further combined with a smaller number of components and components, or further components and components. In addition, the components and components may be implemented to play back one or more CPUs in a device or a secure multimedia card. Also, in an embodiment, 'to' may include one or more processors.

For example, 3GPP's High Speed Packet Access (HSPA), LTE (Long Term Evolution or Evolved Universal Terrestrial Radio Access (E-UTRA)), LTE-Advanced To a broadband wireless communication system that provides high-speed, high-quality packet data services such as the LTE-A, 3GPP2 high rate packet data (HRPD), UMB (Ultra Mobile Broadband), and IEEE 802.16e communication standards. . In addition, a 5G or NR (new radio) communication standard is being produced with the fifth generation wireless communication system.

In the LTE system, an OFDM (Orthogonal Frequency Division Multiplexing) scheme is used in a downlink (DL) and a Single Carrier Frequency Division Multiple (SC-FDMA) scheme is used in an uplink Access) method. The uplink refers to a radio link through which a UE (User Equipment) or an MS (Mobile Station) transmits data or control signals to a base station (eNode B or base station (BS) The term " wireless link " In the above multiple access scheme, the data or control information of each user is allocated and operated so that the time and frequency resources for transmitting data or control information for each user do not overlap each other, that is, orthogonality is established. .

The LTE system adopts a Hybrid Automatic Repeat reQuest (HARQ) scheme in which a physical layer resends data when a decoding failure occurs in an initial transmission. In the HARQ scheme, if a receiver fails to correctly decode (decode) data, the receiver transmits information indicating a decoding failure (NACK: Negative Acknowledgment) 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 data reception performance. In addition, when the receiver correctly decodes the data, an acknowledgment (ACK) indicating the decoding success is transmitted to the transmitter so that the transmitter can transmit new data.

The terms described below are defined in consideration of the functions of the present invention, and these may vary depending on the intention of the user, the operator, or the custom. Therefore, the definition should be based on the contents throughout this specification. Hereinafter, the base station may be at least one of a gNode B, an eNode B, a Node B, a base station (BS), a wireless access unit, a base station controller, or a node on a network. The terminal may include a user equipment (UE), a mobile station (MS), a cellular phone, a smart phone, a computer, or a multimedia system capable of performing communication functions. In the present invention, a downlink (DL) is a wireless transmission path of a signal transmitted from a base station to a mobile station, and an uplink (UL) is a wireless transmission path of a signal transmitted from a mobile station to a base station. In the following, embodiments of the present invention will be described as an example of an LTE or LTE-A system, but embodiments of the present invention may be applied to other communication systems having a similar technical background or channel form. For example, 5G mobile communication technology developed after LTE-A (5G, new radio, NR) could be included. In addition, embodiments of the present invention may be applied to other communication systems by a person skilled in the art without departing from the scope of the present invention.

In this disclosure, the terms physical channel and signal in a conventional LTE or LTE-A system may be used to describe the proposed method and apparatus. However, the present invention can be applied to wireless communication systems other than LTE and LTE-A systems.

In addition, the contents of this disclosure are applicable to FDD and TDD systems.

In the following description, physical layer signaling is a signal transmission method that is transmitted from a base station to a base station using a downlink control channel of a physical layer or from a mobile station to a base station using an uplink control channel of a physical layer, May be referred to as PHY signaling.

Hereinafter, in the present disclosure, upper signaling or higher layer signaling is a signal transmission method that is transmitted from a base station to a terminal using a downlink data channel of a physical layer or from a terminal to a base station using an uplink data channel of a physical layer, RRC signaling, or L2 signaling, or PDCP signaling, or a MAC control element (MAC CE).

In the following description, the term TPMI refers to a Transmit Precoding Matrix Indicator or Transmit Precoding Matrix Information, and may be expressed in terms of beamforming vector information, beam direction information, and the like.

Hereinafter, uplink (UL) DCI or UL-related DCI in the present disclosure refers to uplink resource setting information, resource setting type information, uplink power control information, cyclic shift of uplink reference signal, Or physical layer control including information required for uplink transmission such as orthogonal cover code (OCC), channel state information (CSI) request, SRS request, MCS information per codeword, Signaling (L1 control).

Referring to FIG. 1, a time axis of a radio resource region is composed of one subframe including 14 OFDM symbols, and a frequency axis is composed of one RB including 12 subcarriers. Accordingly, such a radio resource region can have a total of 168 natural frequency and time positions. In the LTE and LTE-A systems, each unique frequency and time location is called a Resource Element (RE).

Referring to FIG. 1, the following signals may be transmitted in the radio resource region.

1) CRS (Cell Specific RS): A reference signal transmitted periodically for all UEs belonging to one cell, and can be commonly used by a plurality of UEs.

2) DMRS (Demodulation Reference Signal): This is a reference signal transmitted for a specific terminal and is transmitted only when data is transmitted to the corresponding terminal. The DMRS can be composed of a total of 8 DMRS ports. In the LTE and LTE-A systems, ports 7 to 14 correspond to the DMRS ports, and the ports are orthogonality so as not to interfere with each other using CDM (Code Divisional Multiplexing) or FDM (Frequency Divisional Multiplexing) .

3) PDSCH (Physical Downlink Shared Channel): A data channel transmitted in the downlink is used by a base station to transmit traffic to a mobile station, and an RE in which a reference signal is not transmitted is used in a data region 308 of a radio resource region .

4) CSI-RS (Channel Status Information Reference Signal): A reference signal transmitted for UEs belonging to one cell, and is used for measuring channel status. A plurality of CSI-RSs can be transmitted to one cell.

5) Other control channels (PHICH, PCFICH, PDCCH): The terminal transmits ACK / NACK for providing control information necessary for receiving the PDSCH or HARQ for uplink data transmission, Lt; RTI ID = 0.0 > 306 < / RTI >

In the LTE-A system, muting can be set so that the CSI-RS transmitted from another base station can be received without interference to the terminals of the corresponding cell. The muting can be applied at a position where the CSI-RS can be transmitted, and the UE can receive the traffic signal by skipping the radio resource. In LTE-A systems, muting is also referred to as zero-power CSI-RS. Because of the nature of the muting, it is applied to the location of the CSI-RS and the transmit power is not transmitted.

Referring to FIG. 1, the CSI-RS uses a part of the positions indicated by A, B, C, D, E, E, F, G, H, I and J according to the number of antennas transmitting CSI- Lt; / RTI > The muting can also be applied to a part of the positions indicated by A, B, C, D, E, E, F, G, H, In particular, the CSI-RS can be transmitted in 2, 4, or 8 REs depending on the number of antenna ports to transmit. For example, if the number of antenna ports is two, the CSI-RS can be transmitted in half of the specific pattern in FIG. 1, and the CSI-RS can be transmitted in the entire specific pattern when the number of antenna ports is four. In addition, when the number of antenna ports is eight, the CSI-RS can be transmitted using two patterns.

In comparison, muting is always done in one pattern unit. That is, although muting can be applied to a plurality of patterns, if the positions do not overlap with the CSI-RS, they can not be applied to only a part of one pattern. However, it may be applied only to a part of one pattern only when the position of CSI-RS overlaps with the position of muting. For example, when CSI-RS is transmitted for two antenna ports, the CSI-RS transmits signals of the respective antenna ports in two REs connected in the time axis, and signals of the respective antenna ports are divided into orthogonal codes . In addition, if CSI-RS is transmitted for four antenna ports, two additional REs can be used in addition to CSI-RS for two antenna ports to transmit signals for two additional antenna ports in the same way have. The same is true when CSI-RS is transmitted for eight antenna ports. In case of CSI-RS which supports 12 and 16 antenna ports, it is necessary to combine three CSI-RS transmission positions for four existing antenna ports or two CSI-RS transmission positions for eight antenna ports .

In addition, the UE can be allocated CSI-IM (or IMR) with the CSI-RS. The CSI-IM resource has the same resource structure and location as the CSI-RS supporting the 4-port. CSI-IM is a resource for a terminal that receives data from one or more base stations to accurately measure interference from an adjacent base station. For example, if the adjacent base station measures the amount of interference when transmitting data and the amount of interference when not transmitting, the base station can configure the CSI-RS and two CSI-IM resources. At this time, one CSI-IM can always transmit a signal to a neighboring base station, while the other CSI-IM can prevent a neighboring base station from always transmitting a signal, thereby effectively measuring the interference amount of a neighboring base station.

Table 1 shows a Radio Resource Control (RRC) field that configures the CSI-RS setting.

Referring to Table 1, there are four types of settings for channel status reporting based on periodic CSI-RS in the CSI process. The CSI-RS config is for setting the frequency and time location of the CSI-RS resource element. Here, by setting the number of antennas, it is possible to set how many ports the corresponding CSI-RS has. The Resource config sets the location of the resource element in the RB, and the Subframe config sets the period and offset of the subframe.

Table 2 shows the table for Resource config and Subframe config settings currently supported by LTE.

The UE can check the frequency and time location, and the period and offset from Table 2. Qcl-CRS-info sets quasi co-location information for CoMP. The CSI-IM config is for setting the frequency and time location of the CSI-IM to measure interference. Since CSI-IM is always set based on 4 ports, it is not necessary to set the number of antenna ports, and Resource config and Subframe config are set in the same manner as CSI-RS. The CQI report config is used to configure how to report channel status using the corresponding CSI process. In this setting, there are periodic channel status report setting, aperiodic channel status report setting, PMI / RI report setting, RI reference CSI process setting, and subframe pattern setting.

The subframe pattern is used to set up a measurement subframe subset for supporting channel and interference measurements with different characteristics in terms of the channel and interference measurement received by the UE. The measurement sub-frame subset is introduced in the enhanced Inter-Cell Interference Coordination (eICIC) to estimate other interference characteristics of ABS (Almost Blank Subframe) and other non-ABS subframes. In order to measure different channel characteristics between a subframe always operating in the downlink and a subframe capable of dynamically switching from the downlink to the uplink in the eIMTA (enhanced Interference Mitigation and Traffic Adaptation), two IMRs are set and measured To be able to do so. Tables 3 and 4 show the measurement subframe subset IMR for eICIC and eIMTA support.

The eICIC measurement subframe subset supported by LTE is set using csi-MeasSubframeSet1-r10 and csi-MeasSubframeSet2-r10. The MeasSubframePattern-r10 that the field refers to is shown in Table 5.

Referring to Table 5, the left MSB indicates subframe # 0, and when it is 1, it indicates that the measurement subframe is included in the subset of the measurement subframe. Unlike the eICIC measurement subframe subset where each subframe set is set via a respective field, the eIMTA measurement subframe subset uses one field to indicate 0 as the first subframe set, And a second set of subframes. Therefore, in the eICIC, the subframe may not be included in the two subframe sets, but in the case of the eIMTA subframe set, the subframe should always be included in one of the two subframe sets.

In addition to this, there is a codebook subset restriction which sets a P _C indicating a power ratio between a PDSCH and a CSI-RS RE necessary for the UE to generate a channel status report and a codebook to use for the codebook. P _C and codebook subset restriction indicate the setting for each subframe subset according to the pC-AndCBSRList field including two pC-AndCBSR fields in Table 7 in Table 7.

P _C can be defined as in Equation (1), and a value between -8 and 15 dB can be specified.

[Equation 1]

The BS can variably adjust the CSI-RS transmission power for various purposes such as improving the channel estimation accuracy, and the UE can determine the transmission power to be used for the data transmission through the notified P _C to be lower or higher than the transmission power used for the channel estimation I can tell. Therefore, even if the base station changes the CSI-RS transmission power, the UE can calculate the correct CQI and report it to the base station.

In a cellular system, a base station must transmit a reference signal to a mobile station in order to measure a downlink channel condition. In the LTE-A (Long Term Evolution Advanced) system of the 3GPP, the UE measures the channel state between the BS and the BS using the CRS or the CSI-RS, do. Several factors need to be taken into consideration in measuring the channel state, including the amount of interference in the downlink. The amount of interference in the downlink includes an interference signal generated by the antenna belonging to the adjacent base station, thermal noise, and the like, and the terminal is importantly used for determining the channel condition of the downlink. For example, when transmitting a signal from a base station with one transmitting antenna to a terminal with a receiving antenna, the terminal uses the reference signal received from the base station to transmit the energy per symbol and the corresponding symbol It is necessary to determine the interference amount to be simultaneously received in the receiving section and determine Es / Io. The determined Es / Io is converted into a data transmission rate or a value corresponding thereto, and is notified to the base station in the form of a channel quality indicator (CQI), thereby enabling the base station to transmit to the terminal at a certain data transmission rate in the downlink To be able to judge whether or not to do.

In the case of the LTE-A system, the UE feeds back information on the downlink channel state to the base station so that it can be utilized for downlink scheduling of the base station. That is, the UE measures the reference signal transmitted from the base station in the downlink, and feeds back the extracted information to the base station in a form defined by the LTE / LTE-A standard. There are three main types of information that the UE feedbacks in LTE / LTE-A.

Rank Indicator (RI): The number of spatial layers that the UE can receive in the current channel state.

- Precoder Matrix Indicator (PMI): Indicator for the preferred precoding matrix in the current channel state

- Channel Quality Indicator (CQI): The maximum data rate that the terminal can receive in the current channel state. The CQI can be replaced by a SINR that can be used similar to the maximum data rate, a maximum error correction coding rate and modulation scheme, and data efficiency per frequency.

RI, PMI, and CQI are related to each other. For example, the precoding matrices supported by LTE, LTE-A and similar systems are defined differently by rank. Thus, the PMI value when RI has a value of 1 and the PMI value when RI has a value of 2 can be interpreted differently even if the values are the same. Also, when the UE determines the CQI, the CQI is determined on the assumption that the Rank value and the PMI value notified to the base station are applied by the base station. That is, when the UE reports RI_X, PMI_Y, and CQI_Z to the base station, it means that the UE can receive a data rate corresponding to CQI_Z when the rank is RI_X and the precoding is PMI_Y. In this way, when calculating the CQI, the UE assumes which transmission scheme is to be performed by the base station, so that the UE can obtain optimized performance when the transmission is performed according to the transmission scheme.

In LTE, LTE-A, and similar systems, the periodic feedback of the terminal is set to one of the following four reporting modes (feedback mode) depending on what information it contains.

- Reporting mode 1-0 (wideband CQI with no PMI): RI, wideband CQI (wCQI)

- Reporting mode 1-1 (wideband CQI with single PMI): RI, wCQI, PMI

- Reporting mode 2-0 (subband CQI with no PMI): RI, wCQI, subband CQI (sCQI)

- Reporting mode 2-1 (subband CQI with single PMI): RI, wCQI, sCQI, PMI

The feedback timing of each information for the four reporting modes is transmitted to a higher layer signal

,

And

And the like. In reporting mode 1-0, the transmission period of wCQI is

And

The feedback timing is determined with the sub-frame offset value of < RTI ID = 0.0 > Also, the transmission cycle of RI is

·

And the offset is

+

to be.

2 is a cross-

Lt; / RTI > and < RTI ID = 0.0 > wCQI < / RTI >

Referring to FIG. 2, the reporting mode 1-1 has the same feedback timing as the mode 1 - 0 but has a difference that wCQI and PMI are transmitted together at the wCQI transmission timing.

The feedback period for sCQI in reporting mode 2-0 is

And the offset value is

to be. And the feedback period for wCQI is

And the offset value is equal to the offset value of sCQI

to be. here,

Is defined as

Is transmitted as an upper signal

Is a value determined according to the system bandwidth. For example, for a 10 MHz system

The value can be defined as 3. As a result, wCQI

The sCQI is transmitted once every sCQI transmission. Also, the cycle of RI is

And the offset is

+

to be.

3,

The timing of feedback of RI, sCQI and wCQI for the case of Fig.

The reporting mode 2-1 has the same feedback timing as mode 2-0 but the PMI is transmitted together at the wCQI transmission timing.

The feedback timing described above is a feedback timing when the number of CSI-RS antenna ports is four or less. In the case of a UE that is allocated CSI-RS for eight antenna ports, two PMI information are fed back do. More specifically, for the eight CSI-RS antenna ports, the reporting mode 1-1 is again divided into two submodes. In the first submode, the RI is transmitted together with the first PMI information, and the second PMI information is transmitted to the wCQI Are transmitted together. Here, the period and the offset of the feedback for the wCQI and the second PMI are

Wow

And the feedback period and the offset value for the RI and the first PMI information are defined as

Wow

+

. When the precoding matrix corresponding to the first PMI is W1 and the precoding matrix corresponding to the second PMI is W2, the terminal and the base station transmit information indicating that the preferred precoding matrices of the terminal are W1 and W2, respectively Share.

Figures 4 and 5 show

The case of PTI = 0 and the case of PTI = 0, respectively.

In reporting mode 2-1 for eight CSI-RS antenna ports, feedback of precoding type indicator (PTI) information is added. The PTI is fed back along with the RI,

And the offset is

+

. If the PTI is 0, the first PMI, the second PMI, and the wCQI are both fed back, and the wCQI and the second PMI are transmitted together at the same timing.

And the offset is

. Also, the period of the first PMI is

And the offset is

to be. here,

Is transmitted as an upper signal. If the PTI is 1, the PTI is transmitted with the RI, the wCQI and the second PMI are transmitted together, and the sCQI is further fed back at a separate timing. In this case, the first PMI is not transmitted. The period and offset of PTI and RI are the same as when PTI is 0 and sCQI is the period

Offset

. Also, the wCQI and the second PMI

And

Lt; RTI ID = 0.0 >

Is defined as when the number of CSI-RS antenna ports is four.

3GPP LTE Release 13 and Release 14 standards support non-precoded (CSI-RS) non-precoded (CSI-RS) to support more than 12 CSI-RS ports for 2-D array antennas. The NP CSI-RS supports 8, 12, 16 or more CSI-RS ports using the existing CSI-RS positions in one subframe. The corresponding field is set in CSI-RS-ConfigNZP-EMIMO. The MS can use this to locate and receive CSI-RS resources. In addition, in the BF CSI-RS, individual CSI-RS resources that can be different from each other in number of CSI-RS ports and subframe and codebook subset restriction can be obtained by using csi-RS-ConfigNZPIdListExt-r13 and csi-IM-ConfigIdListExt- It is used as BF CSI-RS. In order to support 2-D antennas in NP CSI-RS, a new 2-D codebook is required, which may vary depending on the dimension antenna, oversampling factor, and codebook settings. When the PMI bits of the 2-D codebook are analyzed, all of the bits for i2 (W2) reporting can use the existing channel status reporting method of 4 bits or less. However, in case of i11 / i12, PMI bits are increased as follows for N1, N2, O1, O2 and codebookConfig which are supported as shown in Table 8.

Referring to Table 8, it can be confirmed that i1 when (N1, N2, O1, O2) = (2, 4, 8, 8) and Config is 1 should transmit a maximum of 10 bits. Reed-Muller codes used for channel coding can be transmitted up to 13 bits in the case of PUCCH format 2 used in the existing periodic channel status reporting. However, since the extended CP requires 2 bits of HARQ ACK / NACK, The size of the payload that can be transmitted in the situation is 11 bits. To support this payload size, both the broadband CQI mode and the subband CQI mode utilize the three independent CSI feedback timings shown in FIG.

LTE, LTE-A, and similar systems support periodic feedback as well as periodic feedback of the terminal. When a base station desires to acquire aperiodic feedback information of a specific UE, the Node B performs specific non-periodic feedback with an aperiodic feedback indicator included in downlink control information (DCI) for uplink data scheduling of the UE And performs uplink data scheduling of the corresponding terminal. When the UE receives the indicator set to perform aperiodic feedback in the nth subframe, the UE performs uplink transmission including the aperiodic feedback information in the data transmission in the (n + k) th subframe. Here, k is a parameter defined in the 3GPP LTE Release 11 standard, 4 in frequency division duplexing (FDD) and defined in Table 9 in time division duplexing (TDD).

When aperiodic feedback is set, the feedback information includes RI, PMI, CQI as in the case of periodic feedback, and RI and PMI may not be fed back depending on the feedback setting. In addition, the CQI may include both wCQI and sCQI or may include only wCQI information.

LTE, LTE-A or similar systems provide codebook subsampling for periodic channel status reporting. In LTE, LTE-A or similar systems, periodic feedback of the terminal is transmitted to the base station via the PUCCH. Since the amount of information that can be transmitted at one time through the PUCCH is limited, various feedback objects such as RI, wCQI, sCQI, PMI1, wPMI2, and sPMI2 may be transmitted to the PUCCH through sub- sampling or two or more feedback information may be combined (joint encoding) and transmitted on the PUCCH. For example, when eight CSI-RS ports are set in the base station, RI and PMI1 reported in submode 1 of PUCCH mode 1-1 can be coded together as shown in Table 11. Based on Table 10, RI consisting of 3 bits and PMI1 consisting of 4 bits can be jointly encoded with 5 bits in total. Submode 2 of PUCCH mode 1-1 can be combined with PMI1 of 4 bits and PMI2 of 4 bits as a total of 4 bits as shown in Table 11. For submode 2, we can report more precoding indexes because we have larger sub-sampling levels compared to submode 1 (4-> 3 for submode 1 and 8-> 4 for submode 2). I will not. As another example, when there are eight CSI-RS ports set by the base station, the PMI2 reported in the PUCCH mode 2-1 can be sub-sampled as shown in Table 12. Referring to Table 12, PMI2 is reported as 4 bits when the associated RI is 1. However, if the associated RI is greater than or equal to 2, the differential CQI for the second codeword must be reported together, so that PMI2 is extracted and reported as 2 bits.

Referring to FIG. 7, if URLLC data is generated and transmitted while eMBB data and mMTC data are allocated and transmitted in a specific frequency band, eMBB data and mMTC data may be pre-allocated and the URLLC data may be transmitted . Since the URLLC service is particularly important for a short delay time, URLLC data can be allocated to a part of resources to which eMBB data is allocated, and the resource to which such eMBB data is allocated can be informed to the UE in advance. For this, eMBB data may not be transmitted in a frequency-time resource where eMBB data and URLLC data are overlapped, and thus the transmission performance of eMBB data may be lowered. That is, the transmission of the eMBB data due to the allocation of the URLLC data may occur. At this time, the length of the transmission time interval (TTI) used for transmitting the URLLC data may be shorter than the length of the TTI used for transmission of eMBB data or mMTC data.

In addition, a resource (FCR # 1) for a technology to be applied in the future among the radio resources may be provided.

A synchronization signal is used to acquire synchronization with a cell in a network in a process of a terminal accessing a wireless communication system. More specifically, the synchronization signal refers to a reference signal transmitted by the base station for time and frequency synchronization and cell search at the initial connection of the terminal. In the LTE and LTE-A and similar systems, the synchronization signal includes a primary synchronization signal (PSS) Secondary Synchronization Signal) may be transmitted for synchronization.

Referring to FIG. 8, in the 5G or NR system, the synchronization signal 801 may be transmitted in a constant synchronization signal period 803 in terms of time axis. In addition, the synchronization signal 801 can be transmitted through a constant synchronization signal transmission bandwidth 805 in terms of the frequency axis. The synchronization signal 801 may map a special sequence to the subcarriers in the synchronization signal transmission bandwidth 805 to indicate the cell number (Cell ID). In this case, the cell number may be mapped by a combination of one or a plurality of sequences. The terminal may detect the number of a cell to which the terminal desires to connect by detecting the sequence used for the synchronization signal.

The sequence used for the synchronization signal may be a sequence having a CAZAC (Constant Amplitude Zero Auto Correlation) characteristic such as a Zadoff-Chu sequence or a Golay sequence, or a Pseudo Random Noise sequence such as an M-sequence or a Gold sequence. Hereinafter, it is assumed that the above-described synchronous signal is used. However, such a synchronous signal is only a temporary example, and a synchronous signal having various sequences can be used.

The synchronization signal 801 may be configured using one OFDM symbol or a plurality of OFDM symbols. When the synchronization signal 801 is configured using a plurality of OFDM symbols, a sequence for a plurality of different synchronization signals may be mapped to each OFDM symbol. For example, similar to LTE, three Zadoff-Chu sequences can be used to generate a Primary Synchronization Signal (PSS) and Gold Sequence to generate a Secondary Synchronization Signal (SSS). The PSS of one cell may have three different values according to the physical layer cell ID of the cell, and three cell IDs in one cell ID group correspond to different PSSs. Accordingly, the UE detects the PSS of the cell and can identify one of the three cell ID groups supported by the LTE system. The MS can additionally detect the SSS among the 168 cell IDs reduced from 504 through the cell ID group confirmed through the PSS and finally obtain the cell ID to which the corresponding cell belongs.

As described above, the UE can perform synchronization with cells in the network, obtain a cell number (Cell ID), and obtain cell frame timing. Then, the terminal must receive the system information of the cell. System information is information repeatedly broadcast by the network, which is the information that the terminal needs to know in order for the terminal to access the cell and to operate properly in the cell. In the LTE system, the system information is transmitted through two different transmission channels, the master information block (MIB) is transmitted using a PBCH (Physical Broadcast CHannel), the SIB (System Information Block) is transmitted using a PDSCH (Physical Downlink Shared CHannel) . The system information included in the MIB includes a downlink transmission bandwidth, PHICH (Physical Hybrid ARQ Indicator CHannel) setting information, and SFN (System frame number).

Referring to FIG. 9, in a 5G or NR system, a PBCH 901 may be transmitted in a constant PBCH period 903 in terms of time axis. In addition, the PBCH 901 may be transmitted over a constant PBCH transmission bandwidth 905 in terms of frequency axis. In order to improve coverage, the base station transmits the same signal in the PBCH period 903, and the terminal can receive and combine it. In addition, when transmitting a PBCH (901), a base station applies a transmission scheme such as TxD (Transmit Diversity) and one DMRS port based precoder cycling using a plurality of antenna ports, The diversity gain can be obtained without any additional information on the diversity gain. Hereinafter, it is assumed that the above-described PBCH is used. However, this is only an example of the PBCH, and the PBCH having various structures can be used without being limited thereto.

In a 5G or NR system, the PBCH 901 may be configured using a plurality of OFDM symbols in a time-frequency domain radio resource, similar to an LTE system, or may be scattered over time-frequency domain radio resources . The terminal must receive and decode the PBCH in order to receive the system information. In the LTE system, the channel estimation for the PBCH can be performed using the CRS.

10 is a diagram for explaining an example of how each service is multiplexed in a 5G or NR system.

Referring to FIG. 10, a BS may allocate a CSI-RS to a whole band 1001 or a plurality of

bands

1003, 1005, 1007, and 1009 to secure initial channel state information to a UE. Since the CSI-RS of the entire band 1001 or the

multiple bands

1003, 1005, 1007, and 1009 requires a large amount of reference signal overhead, it may be disadvantageous to optimize system performance. However, The CSI-RS of the full band 1001 or the

multiple bands

1003, 1005, 1007, and 1009 is essential. After the CSI-RS transmission of the full band 1001 or the

multiple bands

1003, 1005, 1007, and 1009, each service may be provided with different requirements for each service, The need for updates can also vary. Accordingly, after the initial channel state information is obtained, the base station can trigger the subband CSI-RS for each service in the corresponding band according to the needs of each service.

In FIG. 10, a CSI-RS is transmitted for each service at one time, but it is also possible that a CSI-RS for a plurality of services is transmitted if necessary.

The form of CSI-RS transmission and CSI report setting in LTE system and CSI-RS transmission and CSI report setting in 5G or NR system may be different. Unlike LTE system, 5G or NR system can support more flexible channel status reporting configuration than LTE system through resource setting, channel measurement setting, and channel status reporting setting to support channel status reporting.

Referring to FIG. 11, a resource setting, a channel measurement setting, and a channel status report setting necessary for supporting a channel status report in a 5G or NR system are shown. The resource setting, the channel measurement setting, and the channel status report setting may include the following setting information.

- CSI reporting setting: It is possible to set the reporting parameters (eg RI, PMI, CQI, etc.) necessary for channel status reporting on and off. It is also possible to use a type of channel state report (for example, Type I: channel state reporting with low resolution, implicit reporting type, or Type II: channel state reporting with high resolution, (RI, PMI, CQI, BI, CRI, etc.) (whether individually set or combined). In addition, ), Reporting method (periodic, aperiodic, semi-persistent, aperiodic and semi-persistent can be set as one parameter), codebook setting information, PMI type (full / partial band) implicit / explicit or Type I / Type II), channel quality report type (CQI / RSRP), and resource setting for channel status reporting.

- Resource setting: It is the setting including the setting information about the reference signal required for measuring the channel status. CSI-RS resources for channel measurement and CSI-IM (Interference Measurement Resource) resources for interference measurement may be set, and a plurality of resource settings may exist for this purpose. Also, the transmission type (periodic, aperiodic, semi-persistent) of the reference signal, transmission period and offset of the reference signal, and the like can be set.

- Channel measurement setting: Set up mapping or connection between channel status reporting setting and resource setting. For example, if there are N channel status report settings and M resource settings, L links that set up a mapping between these multiple channel status report settings and resource settings may be included in the channel measurement settings. If the reference signal is transmitted in n sub-frames or slots, the reporting time may be D0-0, D1-0, D2-1, D3-2 and D3-3 (for example, , And the reporting time can be defined as n + D0-0 accordingly) can also be set.

5G or NR systems support semi-persistent reference signaling and channel state information transmission in addition to periodic and aperiodic channel status reports supported by LTE. At this time, the periodic and semi-persistent channel state information transmission of the 5G or NR system may not support subband reporting among the reporting modes described above. The PUCCH used in periodic and semi-persistent channel status reports has a limited amount of reports that can be transmitted. Therefore, in the LTE system, the terminal can select and transmit some subbands of the bandwidth part. However, since the report on this selective subband contains extremely limited information, the usefulness of the information is not great. Therefore, by not supporting such inefficient reporting, the complexity of the terminal can be reduced and the efficiency of reporting can be increased. In addition, if the 5G or NR system does not support subband reporting, periodic channel state information reporting may not report PMI, or may transmit only one PMI corresponding to a wideband or a partial band.

5G or NR system, the following reporting modes can be supported.

- Reporting mode 1-0 (wideband CQI with no PMI): RI, wideband CQI (wCQI)

- Reporting mode 1-1 (wideband CQI with single PMI): RI, wCQI, PMI

- Reporting mode 1-2 (wideband CQI with multiple PMI): RI, wideband CQI (wCQI), multiple broadband and narrowband PMI

- Reporting mode 2-0 (subband CQI with no PMI): RI, wCQI, subband CQI (sCQI)

- Reporting mode 2-1 (subband CQI with single PMI): RI, wCQI, sCQI, PMI

- Reporting mode 2-2 (subband CQI with multiple PMIs): RI, wCQI, sCQI of the band selected by the terminal, multiple broadband and narrowband PMI

- Reporting mode 3-0 (subband CQI with no PMI): RI, wCQI, subband CQI (sCQI)

- Reporting mode 3-1 (subband CQI with single PMIs): RI, wCQI, subband CQI (sCQI), PMI

- Reporting mode 3-2 (subband CQI with multiple PMIs): RI, wCQI, full-band subband CQI (sCQI), multiple broadband and narrowband PMI

Similar to periodic channel status reporting, reporting modes 2-0 and 2-2 in the aperiodic channel status reporting report select one of the subbands in the bandwidth part of the terminal and report the effectiveness of the reporting. Which may not be supported in 5G or NR systems. In case of cyclic channel status reporting in the LTE system, the channel status reporting mode can be set using the PMI / RI report setting and the CQI setting, and in the case of the aperiodic channel status reporting, the channel status reporting mode can be set directly. In the 5G or NR system, PMI / RI report setting and CQI report setting necessary for the channel status report setting described above may be provided.

In a 5G or NR system, two types of channel state reporting are supported, with low spatial resolution and high spatial resolution, as follows. Table 13 and Table 14 show these two types of channel status reports, and Table 15 and Table 16 show the reporting overhead required for each type of report.

The Type I channel status report can report the channel status to the base station through RI, PMI, CQI, CSI-RS Resource Indicator (CRI) based on the codebook as in the existing LTE. In comparison, the Type II report is an implicit CSI type similar to the Type I report and can provide a higher type of resolution through more PMI reporting overhead, Precocoder, beam, Co-phase, etc., in a linear combination. Also, in order to report a direct channel state, it may be reported as an explicit CSI type which is different from the conventional CSI type, and a representative example may be a method of reporting a covariance matrix of a channel. It is also possible to report indirect CSI form and direct CSI form combined. For example, the PMI reports the covariance matrix of the channel, but may also report the CQI or RI together.

As such, Type II reporting requires high reporting overhead. Thus, this Type II report may not be suitable for periodic channel state reporting where the number of reportable bits is low. On the other hand, in the case of aperiodic channel status reports, Type II reports requiring high reporting overhead are suitable for reporting aperiodic channel status because they are supported via PUSCH which can support many overheads.

Furthermore, semi-persistent channel status reporting can support Type II reporting. In 5G or NR systems, semi-persistent channel status reporting requires dynamic terminal activity / inactivity compared to periodic channel status reporting, thus requiring relatively high terminal complexity.

In the channel status reporting of LTE, LTE-A and similar systems, the base station transmits the reference signal based on the CSI process and the report-related setting to the UE through the upper layer signal as shown in Table 1. In the case of the non-periodic channel status report, the UE performs reporting with a predefined reporting time and resources through the trigger included in the DCI transmitted through the downlink control signal, Information will be reported.

Referring to FIG. 11, in the 5G or NR system, channel state report setting, resource setting, and link information linking may be included in the channel measurement setting. A method of triggering an aperiodic channel state report by the base station based on the above setting is as follows.

- Non-Periodic Channel Status Report Trigger Method 1: Trigger based on links in measurement setup

- Non-Periodic Channel Status Report Trigger Method 2: Trigger based on channel status reporting settings within measurement setup

Non-Periodic Channel Status Report Trigger Method 1 is a method of triggering based on a link in a measurement setting, and Trigger Method 2 is a method of triggering based on a channel status report setting in a measurement setting. Will be described with reference to Figs. 12 to 15. Fig.

Referring to FIG. 12, a base station may set a link triggered for each trigger field to RRC in advance in order to report an aperiodic channel status. At this time, the base station can directly set the link ID in the trigger setting to set the triggered link.

Referring to FIG. 13, the BS may set a bitmap of links of all cells set in the UE. At this time, the instruction order of the bitmap may be sorted in ascending or descending order based on the cell ID and the link ID. For example, cell IDs can be sorted first, and then sorted in ascending order from MSB to LSB based on link ID within the same cell ID. In FIG. 13, the cell IDs are shown prioritized. However, the link IDs may be prioritized and arranged in descending order.

The base station may report the aperiodic channel status to the terminal using the trigger field, such as Tables 17, 18 and 19, to trigger the channel status report based on the link.

Referring to Table 17, the base station does not trigger the aperiodic channel status report using the indication field, or may trigger all the links of the corresponding cell, and from the bit after '001', the RRC setting May trigger the links triggered for channel status reporting as described in Trigger Method 1. Also, with reference to Table 18, the case where the trigger field is not triggered is excluded. In this case, there may be an option that is not triggered in the presetting of the trigger field such as '001'. Referring to Table 19, except for the aperiodic channel status report setting reporting all links of one cell, it is possible to provide flexibility in the setting of the base station by increasing the degree of freedom of setting. At this time, as in Table 18, there may be an option that is not triggered in the preset of the trigger field which can be set to '000' or the like.

Referring to FIG. 14, the aperiodic channel status report trigger method 2 can be triggered based on the channel status report setting in the measurement setting. The base station may set the channel status report setting triggered by each trigger field to the RRC in advance for the aperiodic channel status report. At this time, the base station can directly set the channel status reporting setting ID in the trigger setting to set the triggered channel status reporting setting.

Referring to FIG. 15, the BS can set the BS using the bitmap of the channel status report settings of all the cells. At this time, the instruction order of the bit map can be sorted in ascending or descending order based on the cell ID and the channel status reporting setting ID. For example, cell IDs can be sorted first, and then sorted in ascending order from MSB to LSB based on the channel status reporting setting ID within the same cell ID. In FIG. 15, although the cell ID is shown as being sorted in priority, the channel status report setting ID may be sorted in priority order, or may be arranged in descending order.

The base station may report the non-periodic channel status to the terminal using the trigger field, such as Tables 20, 21, and 22, in order to trigger based on the channel status report setting.

Referring to Table 20, the base station may not trigger the aperiodic channel status report using the indication field or may trigger all channel status report settings of the corresponding cell, and from the bit after '001' The channel status report settings triggered for channel status reporting via RRC configuration may be triggered as described in trigger method 2. In addition, referring to Table 21, except for cases where the trigger field is not triggered, in this case, there may exist an option that is not triggered in the preset of the trigger field such as '001'. Referring to Table 22, except for the aperiodic channel status report setting for reporting all channel status report settings of one cell, flexibility of setting of the base station can be provided by increasing the degree of freedom of setting. At this time, as in the above-mentioned Table 21, there may exist an option that is not triggered in the presetting of the trigger field such as '000'.

It is possible to indirectly indicate aperiodic CSI-RS for channel measurement and interference measurement using the indication field. Referring to FIG. 16, a base station triggers a channel status report using a link. In this case, if the resource supported for channel measurement in the resource configuration connected to the link is periodic CSI-RS, the aperiodic channel status report can be performed based on the channel measured in the existing periodic CSI-RS resource. Also, if the resource supporting the channel measurement in the resource setting connected to the link is an aperiodic CSI-RS, the aperiodic channel status report can be performed based on the channel measured in the aperiodically set CSI-RS resource . At this time, the aperiodic channel status report trigger and aperiodic CSI-RS can always be transmitted in the same slot or subframe. It is also possible to trigger through the channel status report setting rather than the link as described above.

In order to support channel status reporting, a resource for a desired signal and an interference measurement can be set to the UE through the resource setting shown in FIG. The RRC parameters in Table 23 can be considered for resource setting.

Referring to Table 23, 5G or NR systems can support beam measurement, reporting and management based on resource settings. Also, in 5G or NR systems, MIMO supports a large number of antennas, such as 1024, and high frequency bands such as 30 GHz. Such a millimeter-wave wireless communication exhibits a high linearity and a high path loss due to the characteristics of the band. To overcome this, a hybrid beam forming system combining RF beam and antenna-based analog beamforming and digital precoding- in need. This will be described with reference to Fig.

Unlike the LTE / LTE-A system, which operates at frequencies below 6GHz, the operating band can be extended to a high frequency band up to 100GHz in 5G or NR systems. As the frequency band increases, the attenuation of the channel exponentially increases. Therefore, a method is needed to overcome this in the high frequency band. Beamforming is a method that can effectively overcome channel attenuation in a high frequency band without significantly increasing the number of base stations.

Referring to FIG. 17, a base station and a terminal include an RF chain and a phase shifter for digital beamforming 1710 and analog beamforming 1720. The analog beamforming at the transmission side can be performed by a method of concentrating the signals in a specific direction by changing phases of signals transmitted from the respective antennas using a plurality of antennas and a phase shifter. For this purpose, an array antenna, which is a collection of a plurality of antenna elements, is used. The use of such transmission beamforming can increase the propagation distance of a signal, and since signals are hardly transmitted in directions other than the set direction, there is an advantage that interference to other users is greatly reduced. The receiving side can also perform the receiving beamforming using the receiving array antenna. The receiving beamforming also concentrates the reception of the radio waves in a specific direction to increase the sensitivity of the received signal in the corresponding direction, and can block the interference signal by excluding signals coming in directions other than the direction from the received signal.

Meanwhile, since the interval between the antennas necessary for the analog beamforming is proportional to the wavelength of the carrier wave, the antenna array form factor can be greatly improved when the frequency band is increased. Therefore, a wireless communication system operating in a high frequency band is advantageous for applying a beam forming technique because a relatively higher antenna gain can be obtained as compared with a beamforming technique in a low frequency band.

In order to obtain a higher antenna gain, hybrid beamforming (hybrid beamforming) combining digital precoding used for obtaining a high data rate effect in a conventional multi-antenna system, as well as analog beamforming, 1730) is used. Hybrid beamforming 1730 applies a digital precoding similar to that applied in conventional multiple antennas at baseband when more than one analog beam is formed through beamforming to transmit or receive more reliable signals or to achieve higher system capacity Can be expected.

In this disclosure, a description will be given of a method of measuring beam quality according to beam switching capability of a base station and a terminal, and reporting and using information according to the beam switching capability of the base station and the terminal, when the base station and the terminal support analog, digital or hybrid beam forming.

The most important factor in applying beamforming is to select the optimized beam direction for the base station and the terminal. In order to select the optimized beam direction, the base station and the terminal may support beam sweeping using a plurality of time and frequency resources. The beam sweeping operation of the terminal and the base station will be described with reference to FIGS. 18, 19 and 20. FIG.

Referring to FIG. 18, a base station can transmit a plurality of

transmission beams

1810, 1820, 1830, and 1840 to a mobile station in order to select a transmission beam from the base station. A terminal may determine a beam suitable for communication with a corresponding one of transmission beams received from a base station, and inform the base station of the information. Here, a beam suitable for communication may mean an optimal or optimal beam for transmitting data.

Referring to FIG. 19, a base station may repeatedly transmit the same transmission beam 1910 for selecting a reception beam of a terminal. Based on the repeated transmission of the same transmission beam 1910, the terminal may determine a reception beam for each transmission beam, inform the base station of the information, or use the reception beam determined according to the base transmission beam.

Referring to FIG. 20, a base station or a terminal of a transmission end can transmit a plurality of different transmission beams using different time resources in terms of time axis for beam selection of a terminal or a base station of the reception end. The terminal or the base station receiving the transmission beam measures the quality of the reference signal using CSI, RSRP (Reference Signals Received Power), etc. of the reference signal on the basis of the received transmission beam, A plurality of transmission beams or reception beams can be selected. Although FIG. 20 shows transmission of a reference signal based on another beam through different time resources, it can be equally applied to frequency, cyclic shift and code resources.

In one embodiment, a plurality of transmission beams may be transmitted for transmission beam sweeping, or one transmission beam may be repeatedly applied for reception beam sweeping. In FIG. 20, four transmission beams, that is, transmission beam # 1, transmission beam # 2, transmission beam # 3, and transmission beam # 4 are repeatedly transmitted three times. However, this is merely an example, and the present invention is not limited thereto, and various numbers of transmission beams can be repeatedly transmitted at various times.

Based on the repeated transmission, the UE determines a reception beam for each transmission beam on the basis of the repeated transmission, informs the base station of the reception beam, or can use the reception beam determined according to the base transmission beam.

In one embodiment, the beam management operations, such as beam sweeping, are performed using the channel state reporting frameworks (resource settings, CSI report settings, CSI measurement settings, links, etc.) and periodic, semi-persistent, And may be operated based on periodic CSI-RS transmission and channel status reporting or beam reporting.

5G or NR system, the CSI-RS resource set in the resource configuration is used for repetitive transmission of one transmission beam for multiple beam transmission and reception beam sweeping for transmission beam sweeping, set of CSI-RS resources and setting whether the corresponding CSI-RS resources are individual CSI-RS resources or whether the same CSI-RS resources are repeated. RRC configuration parameters of Table 24 may be provided for this setting.

Referring to Table 24, ResourceSetConfigList is a setting that allows a plurality of CSI-RS resource sets to be set. In this configuration, a plurality of CSI-RS resource sets can be set, and individual CSI-RS resource sets can be individually set through ResourceSetConfig. ResourceSetConfig can include the settings of ResourceSetConfigId, CSI-RS-ResourceConfigList, and CSI-RS ResourceRepetitionConfig. In this case, the ResourceSetConfigId sets an ID for setting the CSI-RS resource set, and the CSI-RS-ResourceConfigList specifies the CSI-RS resources set in the CSI-RS resource set based on the IDs of the CSI- ID to indicate the CSI-RS resource set in the CSI-RS resource set. The CSI-RS ResourceRepetitionConfig determines whether the CSI-RS resources set in the CSI-RS resource set are to be transmitted on the basis of different beams for transmission beam sweeping, or if the individual CSI-RS resources are the same CSI- Can be set. At this time, the CSI-RS ResourceRepetitionConfig may be expressed as BeamRepetitionConfig to indicate whether the CSI-RS resource set supports the same beam or not.

In setting whether to support CSI-RS resource repetition in the CSI-RS resource set configuration, each CSI-RS resource can be set to only 1-port CSI-RS or 1-port or 2-port CSI-RS resources have. In performing the transmission beam sweeping and reception beam sweeping referred to in FIGS. 18 to 20, the transmission beam can be transmitted as many as a large number of antennas (for example, 1024), and when receiving beam sweeping is considered, Lt; / RTI > Therefore, with respect to the CSI-RS resource setting required for beam sweeping, by limiting the number of antenna ports to a maximum of 1 port or 2 ports, it is possible to reduce the overhead required for transmission of reference signals and efficiently support beam management have.

Also, in setting whether to support CSI-RS resource repetition in the CSI-RS resource set, if the OFDM symbols to which CSI-RS resources are transmitted are the same according to the CSI-RS-ResourceMapping setting of each CSI-RS resource , The CSI-RS resource may not allow the iteration setting or allow the terminal to ignore the setting. This is because it is difficult to use the CSI-RS in the same OFDM symbol to measure other received beam quality in the case of the UE sweeping a plurality of reception beams.

In addition, in the case of CSI-RS resource repetition, other settings except for the CSI-RS-ResourceMapping setting, i.e., ResourceConfigType, CSI-RS-timeConfig, NrofPorts, CDMType, CSI-RS-Density, CSI-RS-FreqBand, Pc, ScramblingID May not allow different settings per CSI-RS resource or may cause the UE to ignore the settings. This is because, when the terminal sweeps a plurality of reception beams, when the density of CSI-RS is different, relative comparison of RSRP or CQI for the corresponding beam measurement may be difficult. In addition, when CSI-RS resources with different transmission periods are frequently transmitted and other resources are not transmitted frequently, it is difficult for the reception beam sweeping required by the UE to be performed completely. Additionally, in the case that a different set the boosting P _c or transmission frequency band of CSI-RS-FreqBand of the CSI-RS power, is a reception beam by RSRP different terminal can reduce the accuracy even compensate for the same beam transmit. Therefore, in order to reduce the hardware complexity of the UE in the CSI-RS iterative setting for the CSI-RS resource repetition for reception beam sweep and to efficiently perform the reception beam sweeping operation of the UE, the CSI- -RS Limit the setting of resources.

In the 3GPP NR Release 15 Phase-I standard, up to two or four CRI (CSI-RS Resource Indicator or CSI-RS Resource Set Indicator) and L1 - Supports RSRP reporting. In the LTE system, the RSRP is a linear average of the DL reference signals transmitted in the channel bandwidth. The RSRP measures the strength of a related reference signal transmitted to the UE, and calculates the RSRP of the CSI- To report the measured power value of the resource or resource set. The RSRP-based beam measurement report may not have a problem when considering only the beams supported by the corresponding cell connected to the terminal, but may not operate smoothly when considering other neighboring cells. 21 is a diagram illustrating beam management in this connection cell and beam management in consideration of other cells in the vicinity.

FIGS. 21 to 23 are diagrams for explaining beam management considering other surrounding cells in a downlink, an uplink, and a cross-link according to an embodiment.

When the base station and the terminal support the RSRP based beam management and reporting, the highest RSRP is measured in the beams close to the LOS, and the terminal reports the beam to the base station. However, considering the signals of other cells, the beam having the highest RSRP may cause high interference to the terminals of other cells, which may not be good from the viewpoint of the overall wireless communication system. Therefore, in this case, it may be better to transmit the PDSCH in a different beam direction in consideration of interference from other cells or to transmit the PDSCH to another UE using the corresponding beam.

Referring to FIG. 21,

terminals

2103 and 2104 are terminals located in

base stations

2101 and 2102 and a line of sight (LOS). Therefore, the

terminals

2103 and 2104 can measure high RSRPs in the

base stations

2101 and 2102 and the

beams

2111 and 2131 close to the LOS, respectively. However, the

beams

2111 and 2131 cause interference to each other, so that the communication performance of the

terminals

2103 and 2104 may deteriorate. Therefore, it is preferable that the

base stations

2101 and 2102 communicate with each other using

beams

2112 and 2132 in different directions or use the corresponding

beams

2111 and 2131 in communication with the

other terminals

2105 and 2106 Performance can be obtained.

Therefore, in order to select the beam considering the interference from other cells at the time of beam selection of the terminal, the reference signal received quality (RSRQ) or the signal-to-interference-and-noise ratio (SINR) May need to be reported.

FIG. 21 shows a case in the downlink, but this problem can be considered between the uplink and the cross-link.

Referring to FIG. 22, interference may also occur between the

uplink beams

2210 and 2220 transmitted from the neighboring

terminals

2203 and 2204 to the

base stations

2201 and 2202, respectively. 23, interference may also occur between the downlink beam 2310 and the uplink beam 2320, which are received and transmitted from the

base stations

2301 and 2302 by the

adjacent terminals

2303 and 2304, respectively.

Furthermore, this problem can be considered also in the communication environment (D2D) between the terminals.

As described above, RSRQ can be used for beam management considering other neighboring cells. In the LTE system, RSRQ is defined by Equation (2).

&Quot; (2) "

Here, the RSSI is a wide-band power received by the UE and is measured only in an OFDM symbol including a reference signal, and also includes interference and noise transmitted on the same channel as the power transmitted from the serving cell Value. N is an integer representing the bandwidth (number of RBs) to which the reference signal is transmitted for measurement of the reference signal. According to Equation (2), RSRQ is a value obtained by dividing the intensity of a signal transmitted to a mobile station by the power of a signal including both interference and noise.

However, in the case of the beam cooperative communication, transmission of a signal is performed by combining individual beams, and a transmission power ratio according to a beam-by-beam reference signal is required instead of the total transmission power. Thus, RSRQ according to Equation (2) Not suitable for communication.

According to an exemplary embodiment, a new concept RSRQ may be used to report to the BS in order to perform beam cooperative communication, rather than the existing RSRQ. This new concept of RSRQ can be expressed in terms of beam quality indicator (BQI), beam indicator, RS-SINR, CSI-RS SINR, and SSB-SINR. The RSRQ, BQI, BI, RS-SINR, CSI-RS SINR or SSB-SINR can be defined as Equation (3).

&Quot; (3) "

Here, RSRP _D is the reception power measured from the reference signal for the preferred channel that the terminal should receive from the base station or the terminal, and RSRP _I is the reception power measured from the reference signal for the interference channel received from the other base station or the terminal to be. This new concept of RSRQ can be expressed in various terms such as BQI, BI, RS-SINR, CSI-RS SINR or SSB-SINR. At this time, the bandwidth of the reference signal transmission may be limited to be the same for transmission of the reference signal transmitted for measurement and reporting. In this case, the variable N for the transmission bandwidth may not be required.

In the above, a method of using RSRQ, BQI, BI, RS-SINR, CSI-RS SINR or SSB-SINR in the beam cooperative communication has been described. However, CQI can also be used for quality measure, , The RI PMI CQI may be reported together and the specific reporting actions may be the same or similar to the RSRQ, BQI, BI, RS-SINR, CSI-RS SINR or SSB-SINR mentioned above.

In one embodiment, for reporting for beam cooperative communications, transmission of a plurality of beams is also required for reference signal transmission to the interfering channel as well as reference signals for the preferred channel, as defined in Equation (3).

Referring to FIG. 24, a terminal may receive a reference signal supporting a beam transmission to a preferred channel 2401 and an interference channel 2402. The beam quality can be measured and calculated as shown in Equation (4) through the reference signal for the preferred channel 2401 and the interference channel 2402 that support other transmission beam transmission and same transmission beam repetition transmission, and reported to the base station.

&Quot; (4) "

Referring to FIG. 24 and Equation 4, the UE measures the reception power for the preferred channel 2401 and the interference channel 2402, and calculates the power ratio for the combination of the preferred channel 2401 and the interference channel 2402 The quality of the beam combination can be calculated. In one embodiment, the wireless communication system, as shown in FIG. 24, can support a plurality of transmit beam transmissions in the interfering channel 2402 for supporting interference measurements, and a supporting reference signal setting capable of setting up repeated transmissions of the same beam. have. More specifically, a plurality of CSI-RS resources or a CSI-RS resource set may be set in a resource setting for interference measurement, and a plurality of transmission beams and / or repeated transmission of the same beams may be supported. 5G or NR systems, it is possible to measure interference through ZP (Zero Power) CSI-RS and NZP (Non-Zero Power) CSI-RS, The operation to enable selection is not supported.

In one embodiment, the terminal measurement and reporting operations taking into account a plurality of beams can be set directly via the RRC field. The RRC field may be set for each UE or may be set for each channel status report setting of the UE. It is also possible to indirectly set a terminal measurement and reporting operation considering a plurality of beams through the RRC field. For example, by setting an interference measurement resource for beam cooperative communication or by setting the channel status report based on RSRQ, BQI, BI, RS-SINR, CSI-RS SINR or SSB- Can be set.

When a channel status report for cooperative communication according to an exemplary embodiment is set, the UE can support CRI reporting together. The existing CRI report was to report the index of the CSI-RS resource or the CSI-RS resource set that the RSRP or RI / CQI measured by the terminal has the highest measured or calculated. In contrast, when a channel status report for beam cooperative communication is set, the preferred channel reference signal and the interference channel reference signal resource, which are measured with the highest RSRQ, BQI, BI, RS-SINR, CSI- RS SINR, or SSB- Combinations can be reported. Also, the RSRQ report may be associated with a CRI report sequence. Further, it is possible to report an average RSRQ, one or more maximum RSRQs, and one or more minimum RSRQs together with the CRI.

In one embodiment, the following two methods can be considered to set the reference signal transmission time point for the preferred channel reference signal and the interference channel reference signal measurement.

- Setting the reference signal transmission point for measurement of the preferred channel reference signal and the interference channel reference signal 1: Always transmit at the same time point

- Set the reference signal transmission point for the measurement of the preferred channel reference signal and the interference channel reference signal. Method 2: To allow transmission at a different point in time

Referring to FIG. 25, a reference signal transmission time point for a preferred channel 2501 and a reference signal transmission time point for an interference channel 2502 are always set to be the same (2510), thereby minimizing terminal complexity and standard complexity. . For example, when the reference signal transmission time point for the preferred channel is different from the reference signal transmission time point for the interference channel, the reception beam of the terminal may be changed according to the transmission time point. Accordingly, additional standard support and terminal implementation are required. Accordingly, by setting 2510 the reference signal transmission time point for the preferred channel 2501 and the reference signal transmission time point for the interference channel 2502 to be equal, it is possible to reduce the standard support for the reception beam and the terminal implementation complexity, Can be measured.

The number of CSI-RS resources, the number of CSI-RS resources, or the entire CSI-RS resource set for measurement of a reference signal must be the same, since the number of times of transmission of the preferred channel 2501 and the interference channel 2502 must be the same. The UE may ignore the entire configuration or ignore some reference signaling settings or resources that are not transmitted at the same time.

Referring to FIG. 26, the number of interference channels 2602 is smaller than the number of preferred channels 2601. Therefore, a time point 2610 at which a reference signal is not received on the interference channel 2602 may occur. It is possible to report only the RSRP of the beam, not the beam quality, at a time point 2610 when the reference signal is not received by the interference channel 2602. [ On the other hand, when the number of the preferred channels 2601 is smaller than the number of the interference channels 2602, reporting the RSRP of the interference channel 2602 as the preferred channel 2601 or disregarding the interference channel 2602 at that time It is possible. Further, when the number of reference signal resources set in the preferred channel 2601 and the interference channel 2602 is different, it is also possible to measure and report according to the maximum number of resources.

Referring to FIG. 27, it may be allowed that the reference signal transmission time point 2710 for the preferred channel 2701 and the reference signal transmission time point 2720 for the interference channel 2702 are set differently.

In one embodiment, the reference signal for the preferred channel 2702 and the reference signal for the interference channel 2702 can be transmitted at different times, thereby providing more flexibility in terminal measurement and reporting. In particular, this method does not have to support each reference signal transmission for all possible cases, thereby reducing the time and frequency resources required for reference signal transmission

28 is a diagram for explaining measurement and reporting for beam cooperation of a terminal based on different viewpoint transmission according to an exemplary embodiment.

Referring to FIG. 28A, the UE transmits a reference signal to the transmission beams D1, D2, D3 and D4 and the interference beams I1, I2, I3 and I4 at different points in time. The UE can calculate the RSRP combination for all beam combinations as shown in Equation (5) by measuring the RSRP for each beam using the reference signal transmitted at another time point.

&Quot; (5) "

According to an embodiment, the UE can calculate the RSRQ of the preferred channel and the interference channel through the measurement of each reference signal without measuring the reference signal power for all combinations, so that the time and frequency resources required for the reference signal transmission can be efficiently Not only can it be used, but it also allows the terminal to report more combinations.

In one embodiment, when a preferred channel and an interference channel reference signal are transmitted at different times during measurement and reporting for beam cooperative communications, the receive beams of the terminal used in the measurement of the preferred channel and interference channel reference signals may be different from each other . It is impossible to calculate accurate RSRQ, BQI, BI, RS-SINR, CSI-RS SINR or SSB-SINR when the reception beams of the terminals used for measurement of the respective reference signals are different from each other. Therefore, it should be ensured that the preferred channel reference signal and the interference channel reference signal are measured with the same reception beam.

Referring to (b) of FIG. 28, the contents of the preferred channel and the interference channel reference signal measured by the same beam are shown. In one embodiment, the preferred channel and the interference channel reference signal may be set to be measured with the same beam, and more specifically, for calculation of RSRQ, BQI, BI, RS-SINR, CSI-RS SINR or SSB- It is assumed that the preferred channel and the interference channel reference signal are measured with the same beam or that the terminal applies the reception beam in the same order to the repeated transmission beam transmission and in the case of repeated transmission of the same transmission beam, BSII, BI, RS-SINR, CSI-RS SINR, or SSB-SINR only for the selected preferred channel resources and interfering channel resources. Using the same beam in this way can be expressed as using the same spatial domain receive filter. In addition, it is also possible for the terminal to set the same spatial QCL setting to the preferred channel and the interference channel reference signal, or to use the same beam by sharing one information.

Also, in one embodiment, in the measurement and reporting for beam cooperative communications, if the preferred channel reference signal and the interference channel reference signal are transmitted at different times, then a combination of the preferred channel and the interference channel should be reported to report the CRI . In addition, a resource indication for channel measurement and a resource indication for interference measurement can be independently supported. For example, by supporting IRI (Interference Resource Indicator) similar to CRI and reporting a preferred channel reference signal resource index and an interference channel reference signal resource index measured with good quality, a good beam To the base station. In addition, it is possible to support the IRI to avoid worst case by considering high interference rather than low interference, and it is also possible to report based on RRC that the IRI reports an index of a resource with high interference, It is also possible to set whether or not to report an index of a resource that is visible.

In one embodiment, the base station may use a CSI-RS or SSB resource for existing channel measurements and beam management to provide a low RSRP May report the CSI-RS resource or SSB index being measured through the CRI. The BS receives the resource index and the RSRP value having a low RSRP from the UE, directly calculates the RSRQ or BQI, and uses the result to support the beam-based cooperative communication. If two or more CSI-RS ports are set in the calculation of the RSRP value, the RSRP value can be derived through linear averaging. At this time, the number of reported CRIs may be one or more. In a plurality of CRI reports, the CRI may be mapped in the order of the measured RSRP values or in the order of the measured RSRP values.

In addition, a plurality of CSI-RS resource sets may be considered to allow channel measurement and beam management information with CRI and IRI. In this case, the UE reports an independent CRI for each CSI-RS set, or a CSI-RS resource index for a single resource set or a plurality of resource sets in which a high or low RSRP value among the set CSI- Or an index of the interference measurement resource set. In this case, when the UE reports the index of the CSI-RS resource set, the number of the CSI-IM resource set or the CSI-RS resource set for the interference measurement corresponds to the number of CSI- It may be equal to the number of CSI-RS resource sets.

In this case, the base station can set whether the report for the channel measurement and beam management is high RSRP based report or low RSRP based report by supporting RRC based on whether the report is based on high RSRP or low RSRP have. This setting can also be included as part of the CSI reporting setting. In addition, this setting may also include settings for the number of RSRPs to be reported and the number of CRIs accordingly.

In addition, it may be possible to dynamically switch between high RSRP based or low RSRP based via MAC CE or DCI. At this time, the base station may toggle the existing RRC setting through the MAC CE or the DCI, or may overwrite the existing RRC setting through the new signal. The base station can dynamically switch and report assumptions of the case where the base station is the preferred signal and the case of the interference, so that the base station can be usefully used for DPS (Dynamic Point Selection).

It is also possible to dynamically switch the above-described CRI and RSRP reporting numbers via DCI or MAC CE. Accordingly, it is possible to flexibly support the coverage of the uplink channel control signal or obtain more information by reducing the size of the payload required for reporting according to the radio channel condition between the base station and the terminal.

In one embodiment, a plurality of base stations may share a beam-related reference signal resource configuration and preferred beam information through an X2 interface for inter-base-station reference signal resource sharing for beam cooperation. In the case of the beam-related reference signal resource setting information, it may include a cell ID, a reference signal transmission resource, a periodic, semi-persistent, aperiodic, a period, a slot offset, and a beam / CSI-RS resource repetition. In the case of beam information, the base station may include frequency of use for candidate resources that are frequently used for coordination according to reports of the UE. (For example, 0 degree, 30 degree, 60 degree, ...) in the case of the preferred channel beam candidate resource, or by a CSI-RS resource or resource set (for example, Reference signal resource 0, reference signal resource 1, reference signal resource 2 ...). It is also possible to indicate the frequency of use (very low interference, low interference, moderate interference, high interference, very high interference, etc.) of the corresponding base station for each beam angle and CSI-RS resource. In addition to the preferred channel beam angle, information may also be shared for the interfering channel. In the case of interfering channels, as in the case of the preferred channel, it can be expressed by beam angle (eg 0 degree, 30 degree, 60 degree, ... in horizontal and vertical) or by the CSI- (E.g., reference signal resource 0, reference signal resource 1, reference signal resource 2 ...). This information can also be shared for wideband, but it can also be shared by partial bandwidth, a bandwidth part, or PRB or RBG. Also, the information may be separately shared for the downlink and the uplink.

In the above, a method of using RSRQ, BQI, BI, RS-SINR, CSI-RS SINR or SSB-SINR in the beam cooperative communication has been described. However, CQI can also be used for quality measure, , The RI PMI CQI may be reported together and the specific reporting actions may be the same or similar to the RSRQ, BQI, BI, RS-SINR, CSI-RS SINR or SSB-SINR mentioned above. Also, while the present disclosure has been described by taking the downlink beam cooperative communication as an example, the present disclosure can be equally applied to an uplink, a crosslink, and a side link. In case of an uplink or a side link, the UE can transmit SRS instead of CSI-RS, and an SRS having a plurality of resources can be set for interference measurement in order to measure interference. Also, in the present disclosure, the process of measuring the reference signal transmitted by the base station and reporting the channel status information and the beam management information has been described in the present invention. However, the base station may measure the reference signal and use it to directly transmit data to the terminal, It is also possible to recommend.

In addition to the above, NZP CSI-RS, CSI-IM (ZP CSI-RS based interference measurement) and SRS are used in order to allow the UE to report channel status information and beam management information considering the uplink, It is also possible to set them at the same time. For example, when reporting channel state information and beam management information, four independent resource sets are set. One is NZP CSI-RS for signal channel status measurement and the other is NZP CSI-RS , And a ZP CSI-RS for inter-cell interference measurement, and an SRS set for uplink, cross-link, and side-link interference measurement. In the above example, all four of them are set at once, but some of them may be set. For example, one of the three resource sets is NZP CSI-RS for channel measurement, CSI-IM and SRS for interference measurement, NZP CSI-RS for channel measurement, NZP CSI-RS and SRS for interference measurement And so on.

In addition, it is also possible to set up a plurality of NZP CSI-RS resource sets for interference measurement in order to support interference measurement considering a plurality of TRPs. Currently, NZP CSI-RS based interference measurement is based on one resource set and NZP CSI-RS resource, and each port represents one interference layer. In order to measure interference with consideration of a plurality of TRPs, by expanding such a resource set to a plurality of resources, it is possible to support channel state and beam management information reporting considering a situation where interference is transmitted in a plurality of TRPs.

As described above, when a plurality of same or different types of interference resources are set, the UE can also report IRIs for each interference set. For example, if an NZP CSI-RS and an SRS resource set for interference measurement are set, the IRI can be reported in each of the sets to support selection of an independent optimal combination according to each interference situation.

These resource-specific IRI reports can be set via RRC. For example, if the corresponding RRC is set (ON), independent IRI reporting may be supported for all individual resources, or additional bitmaps may be set for each resource set or resource to support RRC-specific IRI reporting. have.

Referring to FIG. 29, in step 2910, the terminal receives setting information for measuring quality of a beam from a base station from a base station. In one embodiment, the configuration information for measuring the quality of the beam may include measurement setup information and resource setup information for the reference signal. The measurement setup information and the resource setup information for the reference signal may include information about a reference signal for channel measurement. For example, it is possible to transmit a plurality of CSI-RSs, which include a reference signal type, a number of ports of a reference signal, a codebook shape, N1 and N2 as the number of antennas per dimension, O1 and O2 as oversampling factors A plurality of resource configs for setting a subframe config and location, information related to codebook subset restriction, CSI report related information, CSI-process index, non-periodic channel status report trigger, and aperiodic channel status report A candidate number for timing indication, and transmission power information (P _C ).

In one embodiment, the terminal may receive feedback configuration information through the channel status report settings used in the measurement setup. The feedback setting information includes at least one of PMI / CQI reporting, period and offset, RI period and offset, CRI period and offset, wideband / subband, submode, A candidate number for timing indication between the reporting trigger and the aperiodic channel status report, and so on. At this time, the terminal can simultaneously or sequentially receive the setting information for measuring the quality of the beam and the feedback setting information.

In step 2920, the UE determines whether or not each of the interference signals corresponding to the plurality of transmission beams serving as interference to the reference signals for the respective preferred channels corresponding to the plurality of transmission beams received from the base station and the plurality of transmission beams received from the base station And receives reference signals for the channel. Here, the reference signal may include CSI-RS.

In step 2930, the UE receives the setting information, reference signals for each of the plurality of transmission channels corresponding to the plurality of transmission beams received from the base station, reference signals corresponding to a plurality of transmission beams serving as interference to the plurality of transmission beams received from the base station And measures the quality of the beam for a plurality of transmit beams received from the base station based on the reference signals for each interference channel. In one embodiment, the terminal may estimate the quality of the beam between the transmit antenna of the base station and the receive antenna of the terminal based on the received reference signals. The terminal can estimate the beam quality for each antenna port and estimate an additional beam quality for the virtual resource based on the estimate.

In one embodiment, the terminal may generate feedback information based on the measured beam quality and feedback setting information. Such feedback information may include rank, PMI, and CQI, and an optimal CRI may be selected based on the rank, PMI, and CQI. Further, the UE can transmit feedback information to the base station at a predetermined feedback timing according to a base station feedback setting or an aperiodic channel status report trigger and a timing indication between an aperiodic channel status report trigger and an aperiodic channel status report.

Referring to FIG. 30, in step 3010, the BS transmits configuration information for measuring the quality of a beam to a terminal. In one embodiment, measurement setup information and resource setup information for a reference signal may include information about a reference signal for channel measurement. For example, it is possible to transmit a plurality of CSI-RSs, which include a reference signal type, a number of ports of a reference signal, a codebook shape, N1 and N2 as the number of antennas per dimension, O1 and O2 as oversampling factors A plurality of resource configs for setting a subframe config and location, information related to codebook subset restriction, CSI report related information, CSI-process index, non-periodic channel status report trigger, and aperiodic channel status report A candidate number for timing indication, and transmission power information (P _C ).

In one embodiment, the base station may send feedback configuration information to the terminal. The feedback setting information includes at least one of a PMI / CQI reporting status, a period and an offset, an RI period and offset, a CRI period and offset, a wideband / subband, a submode, A candidate number for timing indication between the reporting trigger and the aperiodic channel status report, and so on. At this time, the terminal can simultaneously or sequentially receive the setting information for measuring the quality of the beam and the feedback setting information.

In step 3020, the base station transmits reference signals to the user equipment using a plurality of transmission beams. Here, the reference signal may include CSI-RS.

In step 3030, the Node B receives feedback information on the reference signals from the UE. In one embodiment, the base station receives the feedback information from the terminal at the timing determined by the feedback setting information, and can utilize the feedback information to determine the quality state of the beam between the terminal and the base station.

31, the terminal 3100 may include a transmission / reception unit 3110, a memory 3120, and a processor 3130. The transmission / reception unit 3110, the memory 3120, and the processor 3130 of the terminal 3100 can operate according to the communication method of the terminal 3100 described above. However, the constituent elements of the terminal 3100 are not limited to the above-described examples. For example, the terminal 3100 may comprise more or fewer components than the above-described components. In addition, the transmission / reception unit 3110, the memory 3120, and the processor 3130 may be implemented as a single chip.

The transmission / reception unit 3110 can transmit / receive a signal to / from the base station. Here, the signal may include control information and data. To this end, the transceiver 3110 may include an RF transmitter for up-converting and amplifying the frequency of the transmitted signal, and an RF receiver for low-noise amplifying the received signal and down-converting the frequency of the received signal. However, this is merely an example of the transmitting and receiving unit 3110, and the components of the transmitting and receiving unit 3110 are not limited to the RF transmitter and the RF receiver.

The transceiver 3110 may receive a signal through a wireless channel, output the signal to the processor 3130, and transmit the signal output from the processor 3130 through a wireless channel.

The memory 3120 can store programs and data necessary for the operation of the terminal 3100. [ In addition, the memory 3120 may store control information or data included in the signal obtained at the terminal 3100. [ The memory 3120 may be composed of a storage medium such as a ROM, a RAM, a hard disk, a CD-ROM and a DVD, or a combination of storage media. Also, the memory 3120 may be composed of a plurality of memories. In one embodiment, the memory 3120 may store a program for supporting beam-based collaborative communications.

The processor 3130 can control a series of processes so that the terminal 3100 can operate according to the above-described embodiment. The processor 3130 may be comprised of a plurality of processors. In one embodiment, the processor 3130 receives configuration information for measuring the quality of the beam from the base station by executing a program stored in the memory 3120, and for each preference channel corresponding to the plurality of transmit beams received from the base station And a second reference signal for each interference channel corresponding to a plurality of transmission beams serving as interference to a plurality of transmission beams received from the base station, And measure the quality of the beam for a plurality of transmission beams received from the base station based on the second reference signals.

Referring to FIG. 32, a base station 3200 may include a transmitter / receiver 3210, a memory 3220, and a processor 3230, as shown in FIG. The transmission / reception unit 3210, the memory 3220 and the processor 3230 of the base station 3200 can operate according to the communication method of the base station 3200 described above. However, the constituent elements of the base station 3200 are not limited to the above-described examples. For example, base station 3200 may include more or fewer components than those described above. In addition, the transmission / reception unit 3210, the memory 3220, and the processor 3230 may be implemented in the form of a single chip.

The transmission / reception unit 3210 can transmit / receive a signal to / from the terminal. Here, the signal may include control information and data. To this end, the transceiver 3210 may include an RF transmitter for up-converting and amplifying the frequency of the transmitted signal, and an RF receiver for low-noise amplifying the received signal and down-converting the frequency of the received signal. However, this is only an embodiment of the transmitting and receiving unit 3210, and the components of the transmitting and receiving unit 3210 are not limited to the RF transmitter and the RF receiver.

The transceiver unit 3210 may receive a signal through a wireless channel, output the signal to the processor 3230, and transmit the signal output from the processor 3230 through a wireless channel.

The memory 3220 may store programs and data necessary for the operation of the base station 3200. In addition, the memory 3220 may store control information or data included in the signal obtained at the base station 3200. [ The memory 3220 may comprise a storage medium such as ROM, RAM, hard disk, CD-ROM and DVD, or a combination of storage media. Also, the memory 3220 may be composed of a plurality of memories. In one embodiment, the memory 3220 may store a program for supporting beam-based collaborative communications.

The processor 3230 can control a series of processes for the base station 3200 to operate according to the above-described embodiment of the present invention. The processor 3230 receives the setting information for measuring the quality of the beam from the base station by executing the program stored in the memory 3220 and generates a first reference for each preference channel corresponding to the plurality of transmission beams received from the base station And a second reference signal for each interfering channel corresponding to a plurality of transmission beams serving as interference to a plurality of transmission beams received from the base station, The quality of the beam for a plurality of transmission beams received from the base station can be measured.

It should be noted that the embodiments of the present invention disclosed in the present specification and drawings are only illustrative of the present invention in order to facilitate the understanding of the present invention and are not intended to limit the scope of the present invention. That is, it will be apparent to those skilled in the art that other modifications based on the technical idea of the present invention are possible. Further, each of the above embodiments can be combined with each other as needed. For example, some of the embodiments of the present invention may be combined with each other to operate the base station and the terminal. Although the above embodiments are presented on the basis of the FDD LTE system, other systems based on the technical idea of the above embodiment may be implemented in other systems such as a TDD LTE system, a 5G or NR system.

Claims

A method of supporting beam-based collaborative communication in a terminal,

Receiving configuration information for measuring quality of a beam from a base station;

The first reference signals for the respective preferred channels corresponding to the plurality of transmission beams received from the base station and the respective interference channels corresponding to the plurality of transmission beams serving as interference to the plurality of transmission beams received from the base station Receiving second reference signals; And

And measuring the quality of the beam for a plurality of transmit beams received from the base station based on the setup information, the first reference signals, and the second reference signals.
The method according to claim 1,

Wherein measuring the quality of a beam for a plurality of transmit beams received from the base station comprises:

And measuring the quality of the beam based on a ratio of a reception intensity of the first reference signals to a reception intensity of the second reference signals.
The method according to claim 1,

Wherein the receiving of the first reference signals and the second reference signals comprises:

And receiving the first reference signals and the second reference signals at the same time point.
The method of claim 3,

Wherein measuring the quality of a beam for a plurality of transmit beams received from the base station comprises:

When the number of the first reference signals and the number of the second reference signals are different, the quality of the beam is measured based on the reception intensity of only the received signal, or the quality of the beam is ignored Or measuring the quality of the beam with reference to a greater number of reference signals.
The method according to claim 1,

In the step of receiving the first reference signals and the second reference signals,

Receiving the first reference signals and the second reference signals at different points in time,

Wherein measuring the quality of a beam for a plurality of transmit beams received from the base station comprises:

And measuring a reception intensity of the first reference signals and a reception intensity of the second reference signals received at the different time points and combining the measured reception intensities, A method of supporting beam-based cooperative communication of a terminal, comprising the step of measuring quality.
6. The method of claim 5,

Wherein the receiving of the first reference signals and the second reference signals comprises:

And receiving the first reference signals and the second reference signals received at the different time points using the same reception beam.
The method according to claim 1,

Receiving feedback setting information from the base station;

Generating feedback information based on the measured beam quality and the feedback setting information; And

And transmitting the feedback information to the base station.
A method of supporting beam-based cooperative communication in a base station,

Transmitting setting information for measuring quality of a beam to a terminal;

Transmitting reference signals to the terminal using a plurality of transmission beams; And

And receiving feedback information on the reference signals from the terminal.
9. The method of claim 8,

Further comprising transmitting feedback setting information to the terminal,

Wherein the step of receiving feedback information on the reference signal from the terminal comprises:

And receiving the feedback information based on the feedback setting information.
9. The method of claim 8,

And transmitting and receiving transmission beam related information with a base station transmitting a transmission beam serving as interference with respect to the plurality of transmission beams transmitted by the base station.
In a terminal supporting beam-based cooperative communication,

A transmission / reception unit;

At least one memory for storing a program for supporting beam-based collaborative communication; And

Receiving configuration information for measuring quality of a beam from a base station by executing the program and transmitting first reference signals for each preferred channel corresponding to a plurality of transmission beams received from the base station and a plurality Receiving second reference signals for each interfering channel corresponding to a plurality of transmission beams serving as interferences in the first transmission beam and the second transmission beam, and transmitting, based on the setting information, the first reference signals, At least one processor for measuring a quality of a beam for a plurality of transmit beams received from the at least one processor.
12. The method of claim 11,

Wherein the at least one processor comprises:

And measures the quality of the beam based on a ratio of a reception intensity of the first reference signals to a reception intensity of the second reference signals.
12. The method of claim 11,

Wherein the at least one processor comprises:

The first reference signals and the second reference signals are received at the same time, and when the number of the first reference signals and the second reference signals are different, the quality of the beam Or measures the quality of the beam based on a larger number of reference signals. &Lt; RTI ID = 0.0 > [0002] < / RTI >
12. The method of claim 11,

Wherein the at least one processor comprises:

Receiving the first reference signals and the second reference signals using the same reception beam at different points in time, and calculating reception intensities of the first reference signals and reception intensities of the second reference signals, And measures the quality of a beam for a plurality of transmission beams received from the base station by combining the measured reception strengths.
A base station supporting beam-based cooperative communication,

A transmission / reception unit;

At least one memory for storing a program for supporting beam-based collaborative communication; And

And includes at least one processor for transmitting setting information for measuring quality of a beam to a terminal, transmitting reference signals to the terminal using a plurality of transmission beams, and receiving feedback information about the reference signals from the terminal Base station.