KR20210010268A - Apparatus and method for transmission and reception of data and control signals in wireless communication systems - Google Patents

Abstract

The present disclosure relates to a fifth generation (5G) or pre-5G communication system for supporting a higher data rate than a fourth generation (4G) communication system, such as long-term evolution (LTE). The present disclosure is to transmit and receive data and control information in a wireless communication system. A method for operating a terminal comprises the processes of: receiving an indication for limited buffer rate matching (LBRM) from a base station; acquiring one or more parameters required for performing the LBRM; determining a limited range of parity bits for the LBRM on the basis of the parameters; and transmitting or receiving data on the basis of the limited range.

Description

Device and method for transmitting and receiving data and control signals in a wireless communication system {APPARATUS AND METHOD FOR TRANSMISSION AND RECEPTION OF DATA AND CONTROL SIGNALS IN WIRELESS COMMUNICATION SYSTEMS}

The present disclosure generally relates to a wireless communication system, and more particularly, to a method and apparatus for transmitting and receiving data and control information in a wireless communication system.

4G (4 ^th generation) to meet the traffic demand in the radio data communication system increases since the commercialization trend, efforts to develop improved 5G (5 ^th generation) communication system, or pre-5G communication system have been made. For this reason, the 5G communication system or the pre-5G communication system is called a Beyond 4G Network communication system or a Long Term Evolution (LTE) system (Post LTE) system.

In order to achieve a high data rate, the 5G communication system is being considered for implementation in the ultra-high frequency (mmWave) band (for example, the 60 gigabyte (60 GHz) band). In order to mitigate the path loss of radio waves in the ultra-high frequency band and increase the transmission distance of radio waves, in 5G communication systems, beamforming, massive MIMO, and Full Dimensional MIMO (FD-MIMO) ), array antenna, analog beam-forming, and large scale antenna technologies are being discussed.

In addition, in order to improve the network of the system, in 5G communication system, advanced small cell, advanced small cell, cloud radio access network (cloud RAN), ultra-dense network , Device to Device communication (D2D), wireless backhaul, moving network, cooperative communication, CoMP (Coordinated Multi-Points), and interference cancellation And other technologies are being developed.

In addition, in the 5G system, the advanced coding modulation (Advanced Coding Modulation, ACM) method of FQAM (Hybrid Frequency Shift Keying and Quadrature Amplitude Modulation) and SWSC (Sliding Window Superposition Coding), and advanced access technology, FBMC (Filter Bank Multi Carrier) ), NOMA (Non Orthogonal Multiple Access), and SCMA (Sparse Code Multiple Access) are being developed.

As wireless communication systems such as 5G systems develop, it is expected to be able to provide various services. Therefore, there is a need for a plan for smoothly providing these services.

Based on the above discussion, the present disclosure provides an apparatus and method for effectively performing rate matching in a wireless communication system.

In addition, the present disclosure provides an apparatus and method for limiting transmittable parity bits in a wireless communication system.

In addition, the present disclosure provides an apparatus and method for determining a range in which transmittable parity bits are limited in a wireless communication system.

In addition, the present disclosure provides an apparatus and method for determining parameters for determining a range in which transmittable parity bits are limited in a wireless communication system.

In addition, the present disclosure provides an apparatus and method for determining a band combination used for carrier aggregation (CA) among a plurality of band combinations in a wireless communication system.

In addition, the present disclosure provides an apparatus and method for determining the maximum number of layers when a plurality of bandwidth parts (BWPs) are configured in a wireless communication system.

According to various embodiments of the present disclosure, a method of operating a terminal in a wireless communication system includes a process of receiving an indication for limited buffer rate matching (LBRM) from a base station, and obtaining at least one parameter necessary to perform the LBRM. And determining a limited range of parity bits for the LBRM based on the parameters, and transmitting or receiving data based on the limited range.

According to various embodiments of the present disclosure, in a wireless communication system, a terminal includes a transceiver and at least one processor connected to the transceiver. The at least one processor receives an indication for limited buffer rate matching (LBRM) from the base station, obtains at least one parameter necessary to perform the LBRM, and parity bits for the LBRM based on the parameters A limited range of them may be determined, and data may be transmitted or received based on the limited range.

The apparatus and method according to various embodiments of the present disclosure may effectively perform rate matching using limited parity bits.

The effects obtainable in the present disclosure are not limited to the above-mentioned effects, and other effects not mentioned may be clearly understood by those of ordinary skill in the technical field to which the present disclosure belongs from the following description. will be.

1 illustrates a wireless communication system according to various embodiments of the present disclosure.
2 illustrates a configuration of a base station in a wireless communication system according to various embodiments of the present disclosure.
3 illustrates a configuration of a terminal in a wireless communication system according to various embodiments of the present disclosure.
4 illustrates a configuration of a communication unit in a wireless communication system according to various embodiments of the present disclosure.
5 illustrates a resource structure in a time-frequency domain in a wireless communication system according to various embodiments of the present disclosure.
6A illustrates an example of allocation of service-specific data to frequency-time resources in a wireless communication system according to various embodiments of the present disclosure.
6B illustrates another example of allocation of service-specific data to frequency-time resources in a wireless communication system according to various embodiments of the present disclosure.
7 illustrates a data encoding method in a wireless communication system according to various embodiments of the present disclosure.
8 illustrates an example of using an outer code in a wireless communication system according to various embodiments of the present disclosure.
9A and 9B illustrate configurations of a transmitter and a receiver using an outer code in a wireless communication system according to various embodiments of the present disclosure.
10 shows an example of a process in which one transport block (TB) is encoded in a wireless communication system according to various embodiments of the present disclosure.
11 is a flowchart of a terminal for transmitting or receiving data in a wireless communication system according to various embodiments of the present disclosure.
12 shows an example of a range of transmittable bits according to LBRM (limited buffer rate matching) in a wireless communication system according to various embodiments of the present disclosure.
13 is a flowchart of a terminal for determining the maximum number of layers in a wireless communication system according to various embodiments of the present disclosure.
14 is another flowchart of a terminal for determining the maximum number of layers in a wireless communication system according to various embodiments of the present disclosure.
15 illustrates an example of a section in which ambiguity of a parameter required to perform LBRM occurs in a wireless communication system according to various embodiments of the present disclosure.
16 illustrates another flowchart of a terminal for determining the maximum number of layers in a wireless communication system according to various embodiments of the present disclosure.

Terms used in the present disclosure are used only to describe a specific embodiment, and may not be intended to limit the scope of other embodiments. Singular expressions may include plural expressions unless the context clearly indicates otherwise. Terms used herein, including technical or scientific terms, may have the same meaning as commonly understood by one of ordinary skill in the technical field described in the present disclosure. Among the terms used in the present disclosure, terms defined in a general dictionary may be interpreted as having the same or similar meaning as the meaning in the context of the related technology, and unless explicitly defined in the present disclosure, an ideal or excessively formal meaning Is not interpreted as. In some cases, even terms defined in the present disclosure cannot be interpreted to exclude embodiments of the present disclosure.

In various embodiments of the present disclosure described below, a hardware approach is described as an example. However, since various embodiments of the present disclosure include technology using both hardware and software, various embodiments of the present disclosure do not exclude a software-based approach.

Hereinafter, the present disclosure relates to an apparatus and method for transmitting and receiving data and control information in a wireless communication system. Specifically, the present disclosure instructs the terminal of information on the set of bands assumed by the base station according to the capability information of the terminal, and also describes a description of how the terminal uses the configuration information from the base station to calculate transmission/reception parameters. do.

In the following description, a term referring to a signal, a term referring to a channel, a term referring to control information, a term referring to network entities, a term referring to a component of a device, etc. are for convenience of description. It is illustrated. Accordingly, the present disclosure is not limited to terms to be described later, and other terms having an equivalent technical meaning may be used.

In the following description, a physical channel and a signal may be used in combination with data or control signals. For example, a physical downlink shared channel (PDSCH) is a term that refers to a physical channel through which data is transmitted, but the PDSCH may also be used to refer to data.

Hereinafter, in the present disclosure, higher signaling refers to 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. Higher level signaling may be understood as radio resource control (RRC) signaling or MAC control element (CE).

In addition, in the present disclosure, in order to determine whether a specific condition is satisfied or satisfied, an expression exceeding or less than is used, but this is only a description for expressing an example, and more or less descriptions are excluded. Not to do. Conditions described as'greater than' may be replaced with'greater than', conditions described as'less than' may be replaced with'less than', and conditions described as'more and less' may be replaced with'greater than and less than'.

In addition, the present disclosure describes various embodiments using terms used in some communication standards (eg, 3rd Generation Partnership Project (3GPP)), but this is only an example for description. Various embodiments of the present disclosure may be easily modified and applied to other communication systems.

1 illustrates a wireless communication system according to various embodiments of the present disclosure. 1 illustrates a base station 110, a terminal 120, and a terminal 130 as some of nodes using a radio channel in a wireless communication system. 1 shows only one base station, but another base station that is the same as or similar to the base station 110 may be further included.

The base station 110 is a network infrastructure that provides wireless access to the terminals 120 and 130. The base station 110 has coverage defined as a certain geographic area based on a distance at which a signal can be transmitted. In addition to the base station, the base station 110 includes'access point (AP)','eNodeB, eNB', '5G node', and'next generation nodeB. , gNB)','wireless point','transmission/reception point (TRP)', or another term having an equivalent technical meaning.

Each of the terminal 120 and the terminal 130 is a device used by a user and performs communication with the base station 110 through a radio channel. The link from the base station 110 to the terminal 120 or the terminal 130 is a downlink (DL), and the link from the terminal 120 or the terminal 130 to the base station 110 is an uplink (UL) ). In some cases, at least one of the terminal 120 and the terminal 130 may be operated without user involvement. That is, at least one of the terminal 120 and the terminal 130 is a device that performs machine type communication (MTC) and may not be carried by a user. Each of the terminal 120 and the terminal 130 is a terminal other than'user equipment (UE)','mobile station','subscriber station', and'remote terminal. )','wireless terminal', or'user device', or another term having an equivalent technical meaning.

The base station 110, the terminal 120, and the terminal 130 may transmit and receive radio signals in a millimeter wave (mmWave) band (eg, 28 GHz, 30 GHz, 38 GHz, 60 GHz). In this case, in order to improve the channel gain, the base station 110, the terminal 120, and the terminal 130 may perform beamforming. Here, beamforming may include transmission beamforming and reception beamforming. That is, the base station 110, the terminal 120, and the terminal 130 may impart directivity to a transmitted signal or a received signal. To this end, the base station 110 and the terminals 120 and 130 may select the serving beams 112, 113, 121, and 131 through a beam search or beam management procedure. . After the serving beams 112, 113, 121, 131 are selected, subsequent communication may be performed through a resource having a quasi-co-located (QCL) relationship with the resource transmitting the serving beams 112, 113, 121, 131. have.

If large-scale characteristics of the channel carrying the symbol on the first antenna port can be inferred from the channel carrying the symbol on the second antenna port, the first antenna port and the second antenna port are in a QCL relationship. Can be evaluated. For example, a wide range of characteristics include delay spread, Doppler spread, Doppler shift, average gain, average delay, and spatial receiver parameter. It may include at least one of.

2 illustrates a configuration of a base station in a wireless communication system according to various embodiments of the present disclosure. The configuration illustrated in FIG. 2 can be understood as the configuration of the base station 110. Used below'… Wealth','… The term'group' refers to a unit that processes at least one function or operation, which may be implemented by hardware or software, or a combination of hardware and software.

Referring to FIG. 2, the base station includes a wireless communication unit 210, a backhaul communication unit 220, a storage unit 230, and a control unit 240.

The wireless communication unit 210 performs functions for transmitting and receiving signals through a wireless channel. For example, the wireless communication unit 210 performs a function of converting between a baseband signal and a bit stream according to the physical layer standard of the system. For example, when transmitting data, the wireless communication unit 210 generates complex symbols by encoding and modulating a transmission bit stream. In addition, when receiving data, the wireless communication unit 210 restores the received bit stream through demodulation and decoding of the baseband signal.

In addition, the wireless communication unit 210 up-converts the baseband signal into a radio frequency (RF) band signal and transmits it through an antenna, and down-converts the RF band signal received through the antenna into a baseband signal. To this end, the wireless communication unit 210 may include a transmission filter, a reception filter, an amplifier, a mixer, an oscillator, a digital to analog convertor (DAC), an analog to digital convertor (ADC), and the like. In addition, the wireless communication unit 210 may include a plurality of transmission/reception paths. Further, the wireless communication unit 210 may include at least one antenna array composed of a plurality of antenna elements.

In terms of hardware, the wireless communication unit 210 may be composed of a digital unit and an analog unit, and the analog unit includes a plurality of sub-units according to operating power, operating frequency, etc. It can be composed of. The digital unit may be implemented with at least one processor (eg, a digital signal processor (DSP)).

The wireless communication unit 210 transmits and receives signals as described above. Accordingly, all or part of the wireless communication unit 210 may be referred to as a'transmitter', a'receiver', or a'transceiver'. In addition, in the following description, transmission and reception performed through a wireless channel are used to mean that the above-described processing is performed by the wireless communication unit 210.

The backhaul communication unit 220 provides an interface for performing communication with other nodes in the network. That is, the backhaul communication unit 220 converts the bit stream transmitted from the base station to another node, for example, another access node, another base station, an upper node, a core network, etc., into a physical signal, and converts a physical signal received from another node. Convert to bit string.

The storage unit 230 stores data such as a basic program, an application program, and setting information for the operation of the base station. The storage unit 230 may be formed of a volatile memory, a nonvolatile memory, or a combination of a volatile memory and a nonvolatile memory. In addition, the storage unit 230 provides stored data according to the request of the control unit 240.

The controller 240 controls overall operations of the base station. For example, the control unit 240 transmits and receives signals through the wireless communication unit 210 or through the backhaul communication unit 220. In addition, the control unit 240 writes and reads data in the storage unit 230. In addition, the control unit 240 may perform functions of a protocol stack required by a communication standard. According to another implementation example, the protocol stack may be included in the wireless communication unit 210. To this end, the control unit 240 may include at least one processor. According to various embodiments, the controller 240 may control the base station to perform operations according to various embodiments to be described later.

3 illustrates a configuration of a terminal in a wireless communication system according to various embodiments of the present disclosure. The configuration illustrated in FIG. 3 may be understood as the configuration of the terminal 120. Used below'… Wealth','… The term'group' refers to a unit that processes at least one function or operation, which may be implemented by hardware or software, or a combination of hardware and software.

Referring to FIG. 3, the terminal includes a communication unit 310, a storage unit 320, and a control unit 330.

The communication unit 310 performs functions for transmitting and receiving signals through a wireless channel. For example, the communication unit 310 performs a function of converting between a baseband signal and a bit stream according to the physical layer standard of the system. For example, when transmitting data, the communication unit 310 generates complex symbols by encoding and modulating a transmission bit stream. In addition, when receiving data, the communication unit 310 restores the received bit stream through demodulation and decoding of the baseband signal. In addition, the communication unit 310 up-converts the baseband signal into an RF band signal and transmits it through an antenna, and down-converts the RF band signal received through the antenna into a baseband signal. For example, the communication unit 310 may include a transmission filter, a reception filter, an amplifier, a mixer, an oscillator, a DAC, an ADC, and the like.

In addition, the communication unit 310 may include a plurality of transmission/reception paths. Furthermore, the communication unit 310 may include at least one antenna array composed of a plurality of antenna elements. In terms of hardware, the communication unit 310 may be composed of a digital circuit and an analog circuit (eg, a radio frequency integrated circuit (RFIC)). Here, the digital circuit and the analog circuit may be implemented in one package. In addition, the communication unit 310 may include a plurality of RF chains. Furthermore, the communication unit 310 may perform beamforming.

The communication unit 310 transmits and receives signals as described above. Accordingly, all or part of the communication unit 310 may be referred to as a'transmitting unit', a'receiving unit', or a'transmitting/receiving unit'. In addition, in the following description, transmission and reception performed through a wireless channel are used in a sense including the processing as described above is performed by the communication unit 310.

The storage unit 320 stores data such as a basic program, an application program, and setting information for the operation of the terminal. The storage unit 320 may be formed of a volatile memory, a nonvolatile memory, or a combination of a volatile memory and a nonvolatile memory. In addition, the storage unit 320 provides stored data according to the request of the control unit 330.

The controller 330 controls overall operations of the terminal. For example, the control unit 330 transmits and receives signals through the communication unit 310. In addition, the control unit 330 writes and reads data in the storage unit 320. In addition, the control unit 330 may perform functions of a protocol stack required by a communication standard. To this end, the control unit 330 may include at least one processor or a micro processor, or may be a part of a processor. In addition, a part of the communication unit 310 and the control unit 330 may be referred to as a communication processor (CP). According to various embodiments, the controller 330 may control the terminal to perform operations according to various embodiments to be described later.

4 illustrates a configuration of a communication unit in a wireless communication system according to various embodiments of the present disclosure. 4 shows an example of a detailed configuration of the wireless communication unit 210 of FIG. 2 or the communication unit 310 of FIG. 3. Specifically, FIG. 4 is a part of the wireless communication unit 210 of FIG. 2 or the communication unit 310 of FIG. 3, and illustrates components for performing beamforming.

4, the wireless communication unit 210 or the communication unit 310 includes an encoding and modulating unit 402, a digital beamforming unit 404, a plurality of transmission paths 406-1 to 406-N, and an analog beam. It includes a forming part 408.

The encoding and modulating unit 402 performs channel encoding. For channel encoding, at least one of a low density parity check (LDPC) code, a convolution code, and a polar code may be used. The encoding and modulating unit 402 generates modulation symbols by performing constellation mapping.

The digital beamforming unit 404 performs beamforming on a digital signal (eg, modulation symbols). To this end, the digital beamforming unit 404 multiplies the modulation symbols by beamforming weights. Here, the beamforming weights are used to change the size and phase of a signal, and may be referred to as a'precoding matrix', a'precoder', and the like. The digital beamforming unit 404 outputs digitally beamformed modulation symbols through a plurality of transmission paths 406-1 to 406-N. In this case, according to a multiple input multiple output (MIMO) transmission scheme, modulation symbols may be multiplexed or the same modulation symbols may be provided through a plurality of transmission paths 406-1 to 406-N.

The plurality of transmission paths 406-1 to 406-N convert digital beamformed digital signals into analog signals. To this end, each of the plurality of transmission paths 406-1 to 406-N may include an inverse fast fourier transform (IFFT) operation unit, a cyclic prefix (CP) insertion unit, a DAC, and an up-conversion unit. The CP insertion unit is for an orthogonal frequency division multiplexing (OFDM) scheme, and may be excluded when another physical layer scheme (eg, filter bank multi-carrier (FBMC)) is applied. That is, the plurality of transmission paths 406-1 to 406-N provide an independent signal processing process for a plurality of streams generated through digital beamforming. However, depending on the implementation method, some of the components of the plurality of transmission paths 406-1 to 406-N may be used in common.

The analog beamforming unit 408 performs beamforming on an analog signal. To this end, the digital beamforming unit 404 multiplies the analog signals by beamforming weights. Here, the beamforming weights are used to change the magnitude and phase of the signal. Specifically, the analog beamforming unit 440 may be configured in various ways according to a connection structure between the plurality of transmission paths 406-1 to 406-N and antennas. For example, each of the plurality of transmission paths 406-1 to 406-N may be connected to one antenna array. As another example, a plurality of transmission paths 406-1 to 406-N may be connected to one antenna array. As another example, the plurality of transmission paths 406-1 to 406-N may be adaptively connected to one antenna array, or may be connected to two or more antenna arrays.

The wireless communication system deviates from the initial voice-oriented service, for example, 3GPP high speed packet access (HSPA), long term evolution (LTE) or evolved universal terrestrial radio access (E-UTRA)), LTE-A. (advanced), 3GPP2 high rate packet data (HRPD), UMB (ultra mobile broadband), IEEE 802.16e, and other communication standards, such as a broadband wireless communication system that provides high-speed, high-quality packet data services . In addition, as a fifth generation wireless communication system, a communication standard of 5G or NR (new radio) is being created.

The NR system employs an orthogonal frequency division multiplexing (OFDM) scheme in downlink (DL) and uplink. More specifically, a cyclic-prefix OFDM (CP-OFDM) scheme in downlink and a discrete Fourier transform spreading OFDM (DFT-S-OFDM) scheme in addition to CP-OFDM in uplink were employed. The uplink refers to a radio link through which the terminal transmits data or control signals to the base station, and the downlink refers to a radio link through which the base station transmits data or control signals to the terminal. In the multiple access method, data or control information of each user is classified by assigning and operating time-frequency resources to carry data or control information for each user so that they do not overlap each other, that is, orthogonality is established.

The NR system employs a hybrid automatic repeat request (HARQ) scheme in which a physical layer retransmits corresponding data when a decoding failure occurs in initial transmission. According to the HARQ scheme, when the receiver fails to accurately decode data, the receiver transmits NACK (negative acknowledgment), which is information notifying the transmitter of the decoding failure, so that the transmitter can retransmit the corresponding data in the physical layer. . The receiver can improve data reception performance by combining the data retransmitted by the transmitter with data that has previously failed to be decoded. In addition, when the receiver correctly decodes the data, the transmitter can transmit new data by transmitting an acknowledgment (ACK), which is information indicating success in decoding to the transmitter.

5 illustrates a resource structure in a time-frequency domain in a wireless communication system according to various embodiments of the present disclosure. 5 illustrates a basic structure of a time-frequency domain, which is a radio resource domain in which data or control channels are transmitted in downlink or uplink.

In FIG. 5, the horizontal axis represents the time domain and the vertical axis represents the frequency domain. The minimum transmission unit in the time domain is an OFDM symbol, and N _symb OFDM symbols 502 are gathered to form one slot 506. The length of the subframe is defined as 1.0 ms, and the length of the radio frame 514 is defined as 10 ms. The minimum transmission unit in the frequency domain is a subcarrier, and the bandwidth of the entire system transmission bandwidth is composed of a total of N _BW subcarriers 504.

The basic unit of a resource in the time-frequency domain is a resource element (RE) 512, which can be represented by an OFDM symbol index and a subcarrier index. A resource block (RB or physical resource block, PRB) 508 is defined as N _symb consecutive OFDM symbols 502 in the time domain and N _RB consecutive subcarriers 510 in the frequency domain. Thus, one RB 508 includes N _symb × N _RB REs 512. In general, the minimum transmission unit of data is RB. In the NR system, in general, N _symb =14, N _RB =12, and N _BW and N _RB are proportional to the bandwidth of the system transmission band. The data rate may increase in proportion to the number of RBs scheduled to the terminal. In the NR system, in the case of a frequency division duplex (FDD) system operating by dividing downlink and uplink into frequencies, the downlink transmission bandwidth and the uplink transmission bandwidth may be different from each other. The channel bandwidth represents a radio frequency (RF) bandwidth corresponding to the system transmission bandwidth. [Table 1] and [Table 2] are the correspondence between the system transmission bandwidth, subcarrier spacing (SCS) and channel bandwidth defined in the NR system in a frequency band lower than 6GHz and a frequency band higher than 6GHz. Represents a part of. For example, an NR system having a 100 MHz channel bandwidth with a 30 kHz subcarrier spacing consists of 273 RBs with a transmission bandwidth. In [Table 1] and [Table 2], N/A may be a bandwidth-subcarrier combination that is not supported by the NR system.

Channel bandwidth
[MHz] SCS 5 10 20 50 80 100 Transmission bandwidth configuration
N _RB 15 kHz 25 52 106 207 N/A N/A 30 kHz 11 24 51 133 217 273 60 kHz N/A 11 24 65 107 135

Channel bandwidth
[MHz] SCS 50 100 200 400 Transmission bandwidth configuration
N _RB 60 kHz 66 132 264 N/A 120 kHz 32 66 132 264

In the NR system, scheduling information for downlink data or uplink data is transmitted from the base station to the terminal through downlink control information (DCI). DCI is defined in various formats, depending on each format, whether it is an uplink grant, which is scheduling information for uplink data, or a downlink grant, which is scheduling information for downlink data, and the size of control information is Whether it is a small compact DCI, whether spatial multiplexing using multiple antennas is applied, whether it is a DCI for power control, and the like may be determined. For example, DCI format 1-1, which is scheduling control information for downlink data, may include at least one of the items shown in Table 3 below.

Item Contents Carrier indicator It indicates on which frequency carrier is transmitted. DCI format indicator It is an indicator that distinguishes whether the corresponding DCI is for downlink or uplink. BWP (bandwidth part) indicator Indicate from which BWP is transmitted. Frequency domain resource allocation Indicate the RB in the frequency domain allocated for data transmission. The resources expressed are determined according to the system bandwidth and resource allocation method. Time domain resource allocation It indicates in which OFDM symbol in which slot the data related channel is to be transmitted. VRB-to-PRB mapping Indicate how to map the virtual RB (virtual RB: VRB) index and the physical RB (physical RB: PRB) index. MCS (modulation and coding scheme) Indicate the modulation method and coding rate used for data transmission. That is, it is possible to indicate a coding rate value capable of indicating TBS and channel coding information along with information on whether QPSK, 16QAM, 64QAM, or 256QAM. CBG transmission information (codeblock group transmission information) When CBG retransmission is set, information on which CBG is transmitted is indicated. HARQ process number Indicate the HARQ process number New data indicator (NDI) Indicates whether HARQ initial transmission or retransmission. Redundancy version (RV) It indicates a redundancy version of HARQ. TPC (transmit power control command) for PUCCH (physical uplink control channel) Indicates a transmission power control command for the uplink control channel PUCCH.

In [Table 3], in the case of PDSCH transmission, time domain resource assignment is expressed by information on a slot in which a PDSCH is transmitted and a start symbol position S in a corresponding slot and the number of symbols L to which the PDSCH is mapped. I can. Here, S may be a relative position from the beginning of the slot, L may be the number of consecutive symbols, and S and L are start and length indicator values defined as shown in [Table 4] below: SLIV).

if (L-1)≤7 then
SLIV=14·(L-1)+S
else
SLIV=14·(14-L+11)+(14-1-S)
where 0<L≤14-S

In the NR system, information on the correspondence between the SLIV value and the PDSCH or physical uplink shared channel (PUSCH) mapping type and information on the slot in which the PDSCH or PUSCH is transmitted is configured in one row through RRC configuration in general ( configured) can be. Thereafter, by using the time domain resource allocation of the DCI, the base station indicates the SLIV value, the PDSCH or PUSCH mapping type, and the information on the slot in which the PDSCH or PUSCH is transmitted to the terminal Can deliver.

In the case of the NR system, the PDSCH or PUSCH mapping type is defined as type A and type B. In the case of PDSCH or PUSCH mapping type A, a demodulation reference signal (DMRS) symbol starts in the second or third OFDM symbol in the slot. In the case of PDSCH or PUSCH mapping type B, a DMRS symbol starts in the first OFDM symbol of a time domain resource allocated for PUSCH transmission.

[Table 5] and [Table 6] illustrate combinations of S and L supported for each type of PDSCH and PUSCH.

PDSCH
mapping
type Normal cyclic prefixz Extended cyclic prefixz S L S+L S L S+L Type A {0,1,2,3}
(Note 1) (3,…,14} (3,…,14} {0,1,2,3}
(Note 1) {3,… ,12} {3,… ,12} Type B {0,… ,12} {2,4,7} {2,… ,14} {0,… ,10} {2,4,6} {2,… ,12} Note 1: S=3 is applicable only if dmrs-TypeA-Position = 3

PUSCH
mapping
type Normal cyclic prefixz Extended cyclic prefixz S L S+L S L S+L Type A 0 (4,…,14} (4,…,14} 0 {4,… ,12} {4,… ,12} Type B {0,… ,13} {One,… ,14} {One,… ,14} {0,… ,12} {0,… ,12} {0,… ,12}

DCI may be transmitted in a physical downlink control channel (PDCCH), which is a downlink control channel, through channel coding and modulation. The PDCCH may be used to refer to the control information itself, not the channel. In general, DCI is independently scrambled with a specific radio network temporary identifier (RNTI) or terminal identifier for each terminal, and after adding a cyclic redundancy check (CRC) and channel coding, each terminal is configured as an independent PDCCH and transmitted. The PDCCH is mapped to a control resource set (CORESET) set to the terminal.

Downlink data may be transmitted on the PDSCH, which is a physical channel for transmitting downlink data. The PDSCH may be transmitted after the control channel transmission period, and scheduling information such as a specific mapping position and modulation scheme in the frequency domain is indicated by the DCI transmitted through the PDCCH. Among the control information constituting DCI, through the MCS, the base station notifies the terminal of the modulation scheme applied to the PDSCH to be transmitted and the size of the data to be transmitted (eg, transport block size (TBS). In one embodiment, the MCS is It may be composed of 5 bits or more or fewer bits TBS corresponds to a size before channel coding for error correction is applied to a transport block (TB), which is data to be transmitted by the base station.

In the present invention, the TB (transport block) may include a medium access control (MAC) header, a control element (CE), one or more MAC service data units (SDUs), and padding bits. have. Alternatively, the TB may indicate a unit of data dropped from the MAC layer to a physical layer or a MAC protocol data unit (PDU).

The modulation schemes supported by the NR system are QPSK (quadrature phase shift keying), 16 QAM (quadrature amplitude modulation), 64 QAM, and 256 QAM, and each modulation order (Qm) is 2, 4, 6 or May be 8. That is, in the case of QPSK, 2 bits per symbol, in the case of 16 QAM, 4 bits per symbol, in the case of 64 QAM, 6 bits per symbol may be transmitted, and in the case of 256 QAM, 8 bits per symbol may be transmitted.

In terms of service, the NR system is designed so that various services can be freely multiplexed in time and frequency resources, and accordingly, waveforms/numerology, reference signals, etc. are dynamically or Can be adjusted freely. In wireless communication, in order to provide an optimal service to a terminal, optimized data transmission through measurement of channel quality and interference amount is important, and thus accurate channel state measurement is essential. However, unlike 4G communication, in which the channel and interference characteristics do not change significantly depending on the frequency resource, in the case of the 5G channel, the channel and interference characteristics change significantly depending on the service, so the frequency resource group (FRG) dimension that allows measurement by dividing them. Support of a subset of is required. Meanwhile, the NR system can divide the types of supported services into enhanced mobile broadband (eMBB), massive machine type communications (mMTC), and ultra-reliable and low-latency communications (URLLC). eMBB is a service aiming at high-speed transmission of high-capacity data, mMTC is a service aiming at minimizing terminal power and connecting multiple terminals, and URLLC for high reliability and low latency. Different requirements may be applied according to the type of service applied to the terminal. Examples of resource distribution of each service are shown in FIGS. 6A and 6B below. 6A and 6B, a method in which frequency and time resources are allocated for information transmission in each system is identified.

6A illustrates an example of allocation of service-specific data to frequency-time resources in a wireless communication system according to various embodiments of the present disclosure. In the case of FIG. 6A, resources are allocated for eMBB 622, URLLC 612, 614, 616, and mMTC 632 in the entire system frequency band 610. When URLLC (612, 614, 616) data is generated while eMBB (622) data and mMTC (632) data are allocated and transmitted in a specific frequency band, the already allocated for eMBB (622) and mMTC (632) The URLLC (612, 614, 616) data may be transmitted without emptying or transmitting the part. Since the URLLC requests to reduce the delay time, resources for transmitting URLLC (612, 614, 616) data may be allocated to a portion of the resources allocated to the eMBB 622. Of course, when URLLCs 612, 614, and 616 are additionally allocated and transmitted from the resource to which the eMBB 622 is allocated, the eMBB 622 data may not be transmitted in the overlapping frequency-time resource. Therefore, the eMBB 622 ) Data transmission performance may be lowered. That is, in the above case, data transmission failure of the eMBB 622 may occur due to resource allocation for the URLLCs 612, 614, and 616. The method of FIG. 6A may be referred to as a preemption method.

6B illustrates another example of allocation of service-specific data to frequency-time resources in a wireless communication system according to various embodiments of the present disclosure. FIG. 6B shows an example in which each service is provided in each of the subbands 662, 664, and 666 obtained by dividing the entire system frequency band 660. Specifically, the subband 662 is used for URLLC (672, 674, 576) data transmission, the subband 664 is used for eMBB 682 data transmission, and the subband 666 is used for mMTC 692 data transmission. Information related to the configuration of the subbands 662, 664, 666 may be determined in advance, and the information may be transmitted from the base station to the terminal through higher-level signaling. Alternatively, information related to the subbands 662, 664, 666 may be arbitrarily divided by a base station or a network node, and services may be provided to the terminal without transmitting additional subband configuration information.

According to various embodiments, a length of a transmission time interval (TTI) used for URLLC transmission may be shorter than a length of a TTI used for eMBB or mMTC transmission. In addition, a response of information related to URLLC can be transmitted faster than eMBB or mMTC, and thus, a terminal using the URLLC service can transmit and receive information with a low delay. The structure of a physical layer channel used for each type to transmit the above-described three services or data may be different. For example, at least one of a length of a TTI, a frequency resource allocation unit, a structure of a control channel, and a data mapping method may be different from each other.

Although the three services and three data types have been described above, there may be more types of services and data types corresponding thereto. Even in this case, various embodiments to be described later may be implemented.

7 illustrates a data encoding method in a wireless communication system according to various embodiments of the present disclosure. 7 illustrates that one TB is segmented into several code blocks (CBs) and a CRC is added.

Referring to FIG. 7, a CRC 714 may be added to a rear or front end of one TB 712 to be transmitted in uplink or downlink. The CRC 714 may have 16-bits, 24-bits, or a fixed number of bits in advance, or may have a variable number of bits according to channel conditions, and may be used by the receiver to determine whether channel coding is successful. The block to which the TB 712 and CRC 714 are added is divided into a plurality of CBs 722-1, 722-2, 722-(N-1), and 722-N. It is divided into a predefined size of CB, and in this case, the last CB (722-N) is smaller in size than other CBs, or is configured to have the same length as other CBs by adding 0, random value or 1 Can be. CRCs 732-1, 732-2, 732-(N-1), and 732-N may be added to each of the divided CBs. The CRCs 732-1, 732-2, 732-(N-1), and 732-N may have 16 bits or 24 bits, or a fixed number of bits, and the receiver determines whether channel coding is successful. Can be used for

To generate the CRC 714, the TB 712 and the cyclic generator polynomial may be used. Cyclic generation polynomials can be defined in various ways. For example, cyclic generation polynomial for 24-bit CRC g _CRC24A (D) = D ²⁴ +D ²³ +D ¹⁸ +D ¹⁷ +D ¹⁴ +D ¹¹ +D ¹⁰ +D ⁷ +D ⁶ +D ⁵ +D ⁴ Assume +D ³ +D+1, and if L=24, TB data a ₀ ,a ₁ ,a ₂ ,a ₃ ,... For ,a _A-1 , CRC p ₁ ,p ₂ ,... ,p _L-1 is a ₀ D ^A+23 +a ₁ D ^A+22 +... +a _A-1 D ²⁴ +p ₀ D ²³ +p ₁ D ²² +... +p ₂₂ D ¹ +p ₂₃ may be divided by g _CRC24A (D) to determine the remainder of 0. In the above example, the CRC length L is described as being 24, but the length L may be defined differently, such as 12, 16, 24, 32, 40, 48, 64, etc.

After adding CRC to TB as described above, the sum of TB and CRC is divided into N CBs 722-1, 722-2, 722-(N-1), and 722-N. CRCs 732-1, 732-2, 732-(N-1), and 732-N are added to each of the CBs 722-1, 722-2, 722-(N-1), and 722-N. . The CRC added to each CB may be generated based on a CRC of a different length from when generating the CRC added to the TB or a different cyclic generation polynomial. However, according to another embodiment, the CRC 714 added to the TB and the CRCs 732-1 added to the CBs 722-1, 722-2, 722-(N-1), 722-N, 732-2, 732-(N-1), 732-N) may be omitted depending on the type of channel code to be applied to the CB. For example, when LDPC (low density parity code) code is applied to CB, not turbo code, CRCs 732-1, 732-2, 732-(N-1), 732-N added for each CB Can be omitted. However, even when LDPC is applied, the CRCs 732-1, 732-2, 732-(N-1), and 732-N are the CBs 732-1, 732-2, 732-(N-1). ), 732-N). Also, even when a polar code is used, a CRC may be added or omitted.

As shown in FIG. 7, the maximum length of one CB is determined according to the type of channel coding applied to the TB, and the TB and the CRC added to the TB are divided into CBs according to the maximum length of the CB. In the conventional LTE system, the CB CRC is added to the divided CB, the data bits and the CRC of the CB are encoded as a channel code, and coded bits are determined accordingly, and each coded bit is promised in advance. As described above, the number of rate-matched bits is determined.

8 illustrates an example of using an outer code in a wireless communication system according to various embodiments of the present disclosure. 9A and 9B illustrate configurations of a transmitter and a receiver using an outer code in a wireless communication system according to various embodiments of the present disclosure.

Referring to FIG. 8, one TB is divided into a plurality of codeblocks (CBs), and then bits or symbols 802 at the same position in each CB are encoded using a second channel code. Accordingly, parity bits or symbols 804 are generated. Thereafter, CRCs 806 and 806 may be added to the respective CBs and the parity CBs generated by the second channel code encoding.

Whether or not the CRCs 806 and 808 are added may vary depending on the type of channel code. For example, when the turbo code is used as the first channel code, CRCs 806 and 808 may be added. In the present disclosure, a convolutional code, an LDPC code, a turbo code, a polar code, and the like may be used as the first channel code. However, this is only an example, and various channel codes may be applied to the present disclosure as the first channel code. In the present disclosure, for example, a reed-solomon code, a BCH code, a raptor code, a parity bit generation code, and the like may be used as the second channel code. However, this is only an example, and various channel codes may be used as the second channel code.

9A, when the outer code is not used, a first channel code encoder 912 and a first channel code decoder 922 are included in the transmitter and the receiver, respectively, and the second channel code encoder 914 and the second The channel code decoder 924 may not be included. When the outer code is not used, the first channel code encoder 912 and the first channel code decoder 922 may be configured in the same manner as when the outer code to be described later is used.

Referring to FIG. 9B, when an outer code is used, data to be transmitted may pass through the second channel code encoder 914. Bits or symbols passing through the second channel code encoder 914 may pass through the first channel code encoder 912. When the channel-coded symbols pass through the channel 902 and are received by the receiver, the receiver performs a decoding operation by sequentially using the first channel code decoder 922 and the second channel code decoder 924 based on the received signal. Can be done. The first channel code decoder 922 and the second channel code decoder 924 may perform operations corresponding to the first channel code encoder 912 and the second channel code encoder 914, respectively.

10 shows an example of a process in which one TB is encoded in a wireless communication system according to various embodiments of the present disclosure. 10 illustrates a process of generating one or more parity CBs by applying a second channel code or an outer code to a plurality of TBs divided from one TB.

Referring to FIG. 10, after the CRC 1014 is added to one TB 1012, it may be divided into at least one CB or a plurality of CBs 1022-1 to 1022-N. In this case, when only one CB is generated according to the size of the TB 1012, the CRC may not be added to the corresponding CB. When the outer code is applied to the plurality of CBs 1022-1 to 1022-N, parity CB (PCB)s 1024-1 to 1024-M may be generated. When using the outer code, the parity CBs 1024-1 to 1024-M may be located after the last CB 1022-N. After encoding using the outer code, CRCs 1032-1 to 1032-(N+M) may be added. Thereafter, the CBs and the parity CBs may be encoded according to the channel code together with the CRC.

In the wireless communication system according to various embodiments, the size of the TB may be calculated through the following steps.

를 계산한다.

는

로 계산될 수 있다. 여기에서,

는 하나의 RB에 포함되는 부반송파 개수(예: 12),

는 PDSCH에 할당된 OFDM 심볼 개수,

는 같은 CDM(code division multiplexing) 그룹의 DMRS(demodulation reference signal)가 점유하는, 하나의 PRB 내의 RE 개수,

는 상위 시그널링에 의해 구성되는 하나의 한 PRB 내의 오버헤드가 점유하는 RE 개수(예: 0, 6, 12, 18 중 하나로 설정)를 의미한다. 이후, PDSCH에 할당된 총 RE 개수

가 계산될 수 있다.

는

로 계산된다.

는 단말에게 할당된 PRB 개수를 의미한다. Step 1: The number of REs allocated to PDSCH mapping in one PRB in the allocated resource

Calculate

Is

Can be calculated as From here,

Is the number of subcarriers included in one RB (eg 12),

Is the number of OFDM symbols allocated to the PDSCH,

Is the number of REs in one PRB occupied by DMRS (demodulation reference signal) of the same code division multiplexing (CDM) group,

Denotes the number of REs occupied by overhead in one PRB configured by higher signaling (eg, set to one of 0, 6, 12, 18). Thereafter, the total number of REs allocated to the PDSCH

Can be calculated.

Is

Is calculated as

Means the number of PRBs allocated to the terminal.

는

로 계산될 수 있다. 여기서, R은 부호화율(code rate), Qm은 변조 차수(modulation order), v는 할당된 레이어 개수를 의미한다. 부호화율 및 변조 차수는 제어 정보에 포함되는 MCS 필드와 미리 정의된 대응 관계를 이용하여 전달될 수 있다. 만약,

이면, 이하 단계 3에 따라, 그렇지 아니하면, 이하 단계 4에 따라 TBS가 계산될 수 있다. Step 2: Number of temporary information bits

Is

Can be calculated as Here, R is a code rate, Qm is a modulation order, and v is the number of allocated layers. The coding rate and modulation order may be transmitted using a predefined correspondence relationship with the MCS field included in the control information. if,

If so, TBS can be calculated according to step 3 below, otherwise, according to step 4 below.

와

와 같이

가 계산될 수 있다. 이어, TBS는 이하 [표 7]에서

보다 작지 않은 값 중

에 가장 가까운 값으로 결정될 수 있다. Step 3:

Wow

together with

Can be calculated. Then, TBS in the following [Table 7]

Among the values not less than

Can be determined as the value closest to.

와

에 따라

가 계산될 수 있다. 이어, TBS는

값과 이하 [표 8]과 같은 수도-코드를 통해 결정될 수 있다.Step 4:

Wow

Depending on the

Can be calculated. Next, TBS

It can be determined through a value and a number-code as shown in [Table 8] below.

When one CB is input to the LDPC encoder, parity bits may be added and output. In this case, the size of the parity bit may vary according to the LDPC base graph. Depending on the rate matching method, all parity bits generated by LDPC coding may be transmittable or may be partially transmitted. A method of processing all parity bits generated by LDPC coding to be transferable is referred to as'FBRM (full buffer rate matching)', and a method of limiting the number of transmittable parity bits is'LBRM (limited buffer rate matching)'. Is referred to as. When resources are allocated for data transmission, the LDPC encoder output is input to a circular buffer, and bits of the buffer are repeatedly transmitted as many as the allocated resources.

이 된다. LBRM 방식의 경우,

,

,

은 2/3으로 결정될 수 있다.

을 결정기 위해 전술한 TBS를 결정하는 방식이 사용될 수 있다. 이때, 레이어 개수는 해당 셀에서 단말이 지원하는 최대 레이어 개수로 가정되고, 변조 차수는 해당 셀에서 단말에게 설정된 최대 변조 차수로 또는 설정되지 아니한 경우, 64-QAM로 가정되고, 부호화율은 최대 부호화율인 948/1024로 가정되고,

는

로 가정되고,

는

으로 가정될 수 있다.

은 이하 [표 9]와 같이 정의될 수 있다.If the length of the circular buffer is N _cb and the number of all parity bits generated by LDPC coding is N, in the case of the FBRM scheme,

Becomes. In the case of the LBRM method,

,

,

Can be determined as 2/3.

In order to determine the TBS, the above-described method of determining the TBS may be used. In this case, the number of layers is assumed to be the maximum number of layers supported by the terminal in the cell, and the modulation order is assumed to be the maximum modulation order set for the terminal in the cell or, if not set, 64-QAM, and the coding rate is the maximum coding. Is assumed to be the rate of 948/1024,

Is

Is assumed to be,

Is

Can be assumed

May be defined as shown in [Table 9] below.

In the wireless communication system according to various embodiments, the maximum data rate supported by the terminal may be determined through [Equation 1] below.

는 인덱스 j의 반송파의 최대 레이어 개수,

는 인덱스 j의 반송파의 최대 변조 오더,

는 인덱스 j의 반송파의 스케일링 계수,

는 부반송파 간격을 의미한다.

는 1, 0.8, 0.75, 0.4 중 하나의 값으로서, 단말에 의해 보고될 수 있으며,

는 이하 [표 10]과 같이 주어질 수 있다. In [Equation 1], J is the number of carriers bound by carrier aggregation (CA), Rmax = 948/1024,

Is the maximum number of layers of the carrier at index j,

Is the maximum modulation order of the carrier at index j,

Is the scaling factor of the carrier at index j,

Means subcarrier spacing.

Is one of 1, 0.8, 0.75, and 0.4, and may be reported by the terminal,

May be given as shown in [Table 10] below.

는 평균 OFDM 심볼 길이이며,

로 계산될 수 있고,

는

에서 최대 RB 개수다.

는 오버헤드 값으로, FR1(예: 6 GHz 또는 7.125 GHz 이하 대역)의 하향링크에서는 0.14, 상향링크에서는 0.18로 주어질 수 있으며, FR2(예: 6 GHz 또는 7.125 GHz 초과 대역)의 하향링크에서는 0.08, 상향링크에서는 0.10로 주어질 수 있다. [수학식 1]에 따라, 30 kHz 부반송파 간격에서 100 MHz 주파수 대역폭을 갖는 셀에서의 하향링크에서의 최대 데이터율은 이하 [표 11]과 같이 계산될 수 있다. here,

Is the average OFDM symbol length,

Can be calculated as,

Is

Is the maximum number of RBs in.

Is an overhead value, can be given as 0.14 in the downlink of FR1 (e.g., a band below 6 GHz or 7.125 GHz) and 0.18 in the uplink, and 0.08 in the downlink of FR2 (e.g., a band exceeding 6 GHz or 7.125 GHz). , May be given as 0.10 in uplink. According to [Equation 1], the maximum data rate in the downlink in a cell having a frequency bandwidth of 100 MHz in a 30 kHz subcarrier interval can be calculated as shown in [Table 11] below.

On the other hand, the actual data rate that the terminal can measure in actual data transmission may be a value obtained by dividing the amount of data by the data transmission time. This may be a value obtained by dividing the TBS (TB size) in 1 TB transmission or the sum of TBSs in 2 TB transmission by the TTI length. For example, the maximum actual data rate in the downlink in a cell having a frequency bandwidth of 100 MHz in a 30 kHz subcarrier interval may be determined as shown in Table 12 below according to the number of allocated PDSCH symbols.

The maximum data rate supported by the terminal can be checked through [Table 11], and the actual data rate according to the allocated TBS can be checked through [Table 12]. In this case, according to the scheduling information, there may be a case where the actual data rate is greater than the maximum data rate.

이 결정되는데, 그 과정이 비효율적이거나 파라미터 구성(configuration) 등이 모호하여 기지국 또는 단말에서 LBRM을 안정적으로 적용하기 어려운 문제점이 있다. 이하 본 개시는 이러한 문제를 해결하기 위한 다양한 실시 예들을 설명한다. In a wireless communication system, especially an NR system, a data rate that the terminal can support can be agreed upon between the base station and the terminal. This may be calculated using the maximum frequency band, the maximum modulation order, and the maximum number of layers supported by the terminal. However, the calculated data rate may be different from a value calculated from a size of a TB (transport block size, TBS) and a length of a transmission time interval (TTI) used for actual data transmission. Accordingly, the terminal may be assigned a TBS larger than a value corresponding to the data rate supported by the terminal, and in order to prevent this, there may be restrictions on the TBS that can be scheduled according to the data rate supported by the terminal. It may be necessary to minimize this case and define the operation of the terminal in this case. In addition, when applying LBRM in the communication system defined in the current NR, based on the number of layers or rank supported by the terminal,

This is determined, but there is a problem in that it is difficult to stably apply the LBRM in the base station or the terminal because the process is inefficient or the parameter configuration is ambiguous. Hereinafter, the present disclosure describes various embodiments for solving this problem.

11 is a flowchart of a terminal for transmitting or receiving data in a wireless communication system according to various embodiments of the present disclosure. 11 illustrates a method of operating the terminal 120.

Referring to FIG. 11, in step 1101, the terminal receives an indication for LBRM. The indication for LBRM may be included in information for configuring a channel (eg, PUSCH or PDSCH) used to transmit or receive data. For example, information for configuring a channel may be received through an RRC message. For example, LBRM may be enabled by the'rateMatching' parameter in PUSCH-ServingCellConfig.

In step 1103, the terminal acquires parameters necessary to perform LBRM. Parameters for performing LBRM may include at least one of at least one parameter and a coding rate for calculating the TB size. In addition, the parameter for calculating the TB size may include at least one of a maximum number of layers and a band combination applied to perform CA.

In step 1105, the UE determines a range of transmittable parity bits according to the LBRM. LBRM is a technique of treating a part of parity bits as transmittable bits, and transmitting at least one buffer among transmittable bits through a channel. For example, as shown in FIG. 12, of the parity bits 1204 generated from the information bits 1202, bits within a limited range 1206 indicated by Ncb can be transmitted, and the remaining bits have a redundancy version (RV). Even if it is changed, it is not transmitted. Accordingly, the terminal may determine which range of parity bits to treat as transmit or receive bits. Treating them as transmittable bits can be accomplished by inputting the bits into a circular buffer.

In step 1107, the terminal transmits or receives data according to the LBRM. In other words, in performing encoding or decoding, the terminal performs encoding or decoding in consideration of parity bits within a limited range. In the case of downlink communication, the terminal may operate a buffer having a size corresponding to a limited range to buffer the received data. In the case of uplink communication, the terminal may generate parity bits by encoding information bits, and may include at least one parity bit selected within a limited range among the generated parity bits in transmission data.

As described with reference to FIG. 11, the terminal may perform LBRM. To perform LBRM, the UE determines a limited range for parity bits. To this end, it is required to determine a parameter necessary to determine a limited range (eg, a band combination applied for CA operation or a maximum number of layers). Hereinafter, embodiments for determining a parameter necessary to determine a limited range will be described.

How to determine the band combination

The terminal reports information about its capabilities to the base station while accessing the base station. The capability can report parameters that can be supported by itself (eg, the maximum number of layers, the maximum modulation order, the maximum frequency bandwidth, whether a specific technology is supported, etc.) to the base station. To this end, the base station instructs the UE to provide information on capability by sending a UE capability request message, and the UE provides information on capability by sending a UE capability information message. can do. Information on the capabilities of the terminal may be delivered to the base station through higher-level signaling such as RRC signaling, and the base station may store information on the capabilities of a specific terminal. The information on the capabilities of the terminal stored in the base station can be used for the base station to immediately recognize the capabilities of the terminal when the corresponding terminal next accesses the same base station.

The terminal may transmit information on a frequency band supported by the terminal to the base station as part of the information on the UE capability. The information on the supported frequency band may mean a single frequency band to be supported or combinations of frequency bands that are simultaneously supported. The base station and the terminal may exchange signaling information as shown in [Table 13] below in order to deliver information on a frequency band and a band combination supported by the corresponding terminal. Signaling information as shown in [Table 13] may be referred to as'BandCombinationList information element'.

- ASN1START
- TAG-BANDCOMBINATIONLIST-START

BandCombinationList ::= SEQUENCE (SIZE (1..maxBandComb)) OF BandCombination

BandCombinationList-v1540 ::= SEQUENCE (SIZE (1..maxBandComb)) OF BandCombination-v1540

BandCombinationList-v1550 ::= SEQUENCE (SIZE (1..maxBandComb)) OF BandCombination-v1550

BandCombination ::= SEQUENCE {
bandList SEQUENCE (SIZE (1..maxSimultaneousBands)) OF BandParameters,
featureSetCombination FeatureSetCombinationId,

ca-ParametersEUTRA CA-ParametersEUTRA OPTIONAL,
ca-ParametersNR CA-ParametersNR OPTIONAL,
mrdc-Parameters MRDC-Parameters OPTIONAL,
supportedBandwidthCombinationSet BIT STRING (SIZE (1..32)) OPTIONAL,
powerClass-v1530 ENUMERATED {pc2} OPTIONAL
}

BandCombination-v1540::= SEQUENCE {
bandList-v1540 SEQUENCE (SIZE (1..maxSimultaneousBands)) OF BandParameters-v1540,
ca-ParametersNR-v1540 CA-ParametersNR-v1540 OPTIONAL
}

BandCombination-v1550 ::= SEQUENCE {
ca-ParametersNR-v1550 CA-ParametersNR-v1550
}

BandParameters ::= CHOICE {
eutra SEQUENCE {
bandEUTRA FreqBandIndicatorEUTRA,
ca-BandwidthClassDL-EUTRA CA-BandwidthClassEUTRA OPTIONAL,
ca-BandwidthClassUL-EUTRA CA-BandwidthClassEUTRA OPTIONAL
},
nr SEQUENCE {
bandNR FreqBandIndicatorNR,
ca-BandwidthClassDL-NR CA-BandwidthClassNR OPTIONAL,
ca-BandwidthClassUL-NR CA-BandwidthClassNR OPTIONAL
}
}

BandParameters-v1540 ::= SEQUENCE {
srs-CarrierSwitch CHOICE {
nr SEQUENCE {
srs-SwitchingTimesListNR SEQUENCE (SIZE (1..maxSimultaneousBands)) OF SRS-SwitchingTimeNR
},
eutra SEQUENCE {
srs-SwitchingTimesListEUTRA SEQUENCE (SIZE (1..maxSimultaneousBands)) OF SRS-SwitchingTimeEUTRA
}
} OPTIONAL,
srs-TxSwitch-v1540 SEQUENCE {
supportedSRS-TxPortSwitch ENUMERATED {t1r2, t1r4, t2r4, t1r4-t2r4, t1r1, t2r2, t4r4, notSupported},
txSwitchImpactToRx INTEGER (1..32) OPTIONAL,
txSwitchWithAnotherBand INTEGER (1..32) OPTIONAL
} OPTIONAL
}

- TAG-BANDCOMBINATIONLIST-STOP
- ASN1STOP

It may be information on a band combination (BC). The base station configures information on carrier aggregation (CA) based on the capabilities of the received terminal. For example, the carriers set by the base station for CA to the terminal will be carriers included in the frequency band reported to the base station that the terminal can support.

FR1-band1 FR2-band3 CC1 CC2 CC3 CC4 CC1 CC2 CC3 CC4 BC1 max
layers 8 8 8 8 2 2 2 2

[Table 14] is an example of UE capabilities for one band combination reported by the UE to the base station, and the UE provides the base station to the base station in one band (band 1) and frequency range 2 (FR1). This is an example of reporting that one band (band 3) can be bundled and transmitted/received. Referring to [Table 14], the UE can perform CA using some or all of the four component carriers (CCs) in band 1, and also, using some or all of the additional four CCs in band 3 CA can be done together. In addition, the UE may receive data using a maximum of 8 layers per CC in each carrier of band 1, and may receive data using a maximum of two layers per CC in band 3.

FR1-band1 FR1-band2 FR2-band3 CC1 CC2 CC3 CC4 CC1 CC2 CC3 CC4 CC1 CC2 CC3 CC4 BC1 max
layers 4 4 4 4 4 4 4 4 2 2 2 2

[Table 15] is another example of the UE capability for one band combination reported by the UE to the base station, and one band (band 1) of the frequency range 1 (FR1) and the other band of the FR1 from the UE to the base station This is an example of a case of reporting that one band (band 3) of (band 2) and frequency range 2 (FR1) can be bundled and transmitted/received. Referring to [Table 15], the UE may perform CA using some or all of the four CCs in band 1, and may perform CA using some or all of the four CCs in band 2, Also, CA can be performed together using four CCs in band 3. In addition, the UE may receive data using a maximum of 4 layers per CC in band 1 and band 2, and may receive data using a maximum of 2 layers per CC in band 3.

When the base station configures one or more CCs for CA to the terminal, the terminal may not know what kind of band combination the base station assumes, uses, or applies for the configuration of the corresponding CCs. For example, when the terminal transmits information on the band combination as shown in [Table 14] and [Table 15] to the base station, if the base station configures CA for CC1 and CC2 of band 1, the terminal is [Table 14] And it is difficult to determine which band combination in [Table 15] is applied. This is because both the band combination of [Table 14] and the band combination of [Table 15] include CC1 and CC2 of band 1. In this case, the UE cannot determine whether the maximum number of layers that can be supported in CC1 and CC2 of the corresponding band 1 is 8 or 4.

The following embodiments may be used to resolve the mismatch between the base station and the terminal for a band combination applied or assumed by the base station.

■ Sending an indicator or instruction for the band combination

According to an embodiment, an indicator or instruction for a band combination applied or assumed by the base station to the terminal may be provided. The base station informs the terminal of the RRC configuration or higher signaling configuration indicating which band combination is applied or assumed to the terminal. For example, when the UE reports to the base station the UE capability to inform that both band combination 1 (eg, [Table 14]) and band combination 2 (eg, [Table 15]) are possible, the base station provides the UE with band combination 1 And which band combination is applied or assumed among band combination 2 may be indicated. Information indicating the applied or assumed band combination may be transmitted by a combination of at least one or more of RRC signaling, MAC CE, or DCI. Here, the indicator or instruction may be defined as at least one value indicating a band combination, or may be implicitly expressed or determined by at least one or more other information. Actions that are implicitly expressed or determined may include appropriate computational actions. When implicitly expressed or determined, the band combination may be determined based on or a plurality of other pieces of information or parameters.

■ Determine band combination according to predefined rules

According to an embodiment, the applied or assumed band combination may be confirmed according to a predefined rule without separate signaling. For example, the UE identifies information on the configured CC, identifies possible (or candidate) band combinations including the configured CCs among the band combinations reported to the base station, and has the highest value among the identified band combinations. It can be assumed that a band combination having a parameter (eg, a band combination having the largest number of layers) is applied. That is, when CCs are configured for CA, the UE may determine that a band combination having the highest capability among UE capabilities related to the configured CC is applied. When the maximum number of layers for each band is fixed, a band combination in which the largest number of layers for each band is considered among the band combinations may be assumed or determined. If, in the case of a system in which the maximum number of supported layers is set for each CC in the same band, a band combination in consideration of the maximum number of layers having the largest value for each CC may be assumed or determined in consideration of the configured CC.

As a specific example, assume that there is a band combination as shown in [Table 16] below.

If CA is applied to FR1-Band1-CC1 and FR2-Band1-CC1, both band combinations BC1 or BC2 are possible as described above, and the maximum possible value for the number of maximum layers (max_layers) for each CC is ( It can be expressed as 8, 2). Hereinafter, in the present disclosure, unless otherwise specified, the maximum value of the maximum layer (max_layers) is sequentially indicated for each band or CC. Accordingly, as described above, when the determination on the band combination is ambiguous, the band combination may be assumed or determined as BC1. In contrast, when CA is applied to FR1-Band1-CC1 and FR1-Band2-CC3, since only band combination BC2 is possible, the maximum number of layers (max_layers) can be determined to be exactly (4, 4).

In this way, after confirming or determining candidate band combinations in which a band or CC combination can be set for one band or CC combination reported by the UE to the base station, the reported band combination is determined based on all or at least part of the candidate band combinations. It is possible to check or determine the maximum number of layers (max_layers) for each band or CC that may have. In the above-described embodiments, a maximum value of the maximum number of layers (max_layers) that can be set for each band or CC is used in candidate band combinations, but a minimum value or an average value may be used depending on the system. As a result, the maximum number of layers (max_layers) according to each band or CC can be determined based on a combination of candidate bands that can include CCs set for CA and the maximum number of layers defined in a corresponding feature set. And the process can be expressed as follows.

-Identify component-carriers (or bands) configured (or reported) for a carrier aggregation.

-Identify (or Determine) a set of candidate band combinations including a plurality of the component-carriers (or bands) configured (or reported) for a carrier aggregation.

-The maximum number of layers for (corresponding to) a component-carrier (or a band) in the plurality of the component-carriers (or bands) can be determined (or identified) based at least in part on the set of candidate band combinations (and feature sets).

-Example: The maximum number of layers for (corresponding to) a component-carrier (or band) is identified (or determined) by the maximum (or minimum, or average) value of maxNumberMIMO-LayersPDSCH (or maxNumberMIMO-LayersCB-PUSCH, or maxNumberMIMO-LayersNonCB-PUSCH ) across all configurable (or possible or candidate) band combinations and feature sets for the component-carrer (or band).

When the band combination as shown in [Table 16] is possible, when CA is applied to FR1-Band1-CC3 and FR2-Band1-CC3, the possible band combination may be BC1, BC2, or BC4. In this case, the maximum value for the number of maximum layers (max_layers) for each CC may be expressed as (8, 4), but a band combination corresponding to the maximum value (8, 4) may not exist. In the case of determining the band combination according to the predefined rule as described above, as the ambiguity of the parameter increases, the likelihood that it is determined as parameters not considered by the actual system increases. In order to minimize this problem, the band combination should be configured so that parameter ambiguity does not occur as much as possible, but in this case, the constraint on the band combination may become too large.

Accordingly, the present disclosure proposes a band combination having a specific characteristic so as not to deviate as much as possible from a parameter considered in an actual system without increasing the constraint on the band combination. In other words, if at least some of the band combinations have the specific characteristics proposed in the present disclosure, when CA is applied to the CCs included in the band combination set, at least parameters not used in the actual system are used. If it is set, it can be excluded.

Assume that CA is applied to any two CCs or bands as shown in [Table 17].

At this time, consider the case where the following <Condition 1> is satisfied.

<Condition 1>

-When the maximum number of layers (max_layers_11) for the first CC or band of the first band combination is greater than or equal to the maximum number of layers (max_layers_21) for the first CC or band of the second band combination, the first band combination The maximum number of layers (max_layers_12) for 2 CCs or bands is also greater than or equal to the maximum number of layers (max_layers_22) for the second CC or band of the second band combination. ((max_layers11 ≥ max_layers21) AND (max_layers12 ≥ max_layers22))

-Or, when the maximum number of layers (max_layers_11) for the first CC or band of the first band combination is less than or equal to the maximum number of layers (max_layers_21) for the first CC or band of the second band combination, the first band combination The maximum number of layers (max_layers_12) for the second CC or band is also less than or equal to the maximum number of layers (max_layers_22) for the second CC or band of the second band combination.

((max_layers11 ≤ max_layers21) AND (max_layers12 ≤ max_layers22))

If the band combination is set to always satisfy <Condition 1> for [Table 17], in the case of an ambiguous band combination whose parameters are not clearly defined, predetermined values such as the maximum, minimum, or average value for each CC or each band. When the rule is applied, it is possible to assume or determine the parameters of the band combinations that actually exist.

For example, if [Table 16] is changed as shown in the following [Table 18] or [Table 19] to satisfy the above <Condition 1>, in any case, the parameters for the maximum number of actually existing layers can be assumed. Therefore, the selected parameter may not significantly deviate from the considerations of the system.

If the above <Condition 1> is used, it can be applied as a simple rule that always determines the parameter to be considered in the actual system even when the parameter is ambiguous. However, since the band combination constraint may slightly increase, if the above <Condition 1> is more relaxed, the possibility of not being set as a parameter considered in the actual system increases, but the limitation on band combination can be reduced. have.

For example, assume that there is a band combination that satisfies the following conditions as in <Condition 2>.

<Condition 2>

-The difference between the maximum number of layers (max_layers_11) for the first CC or band of the first band combination and the maximum number of layers (max_layers_21) for the first CC or band of the second band combination is less than the first reference value X (or The difference between the maximum number of layers (max_layers_12) for the second CC or band of the first band combination and the maximum number of layers (max_layers_22) for the second CC or band of the second band combination is the second reference value Y Less than (or less than or equal to. X and Y may be the same positive integers. (|max_layers11-max_layers21| ≤ X AND |max_layers11-max_layers21| ≤ Y)

If the same conditions as in <Condition 2> above are applied, the degree of freedom in selecting the band combination that can be set in the system increases, but there may be a large difference from the parameters considered in the actual system. Is required. In addition, X and Y values may be set in consideration of the characteristics of a band in which each CC is set. X and Y may be set to the same value, for example X=Y=1 or X=Y=2 or X=Y=4, but (X, Y) = (2, 1) or (4 , 2) or (4, 1), X and Y may be set to different values.

Different criteria may be applied depending on whether the CC belongs to FR1 or FR2 as follows.

<Condition 3>

-When the 1st CC and 2nd CC are set in FR1,

(|max_layers11-max_layers21| ≤ X1)

AND (|max_layers11-max_layers21| ≤ Y1)

-When the first CC is set in FR1 and the second CC is set in FR2,

(|max_layers11-max_layers21| ≤ X1)

AND (|max_layers11-max_layers21| ≤ Y2)

-When the first CC is set in FR2 and the second CC is set in FR1,

(|max_layers11-max_layers21| ≤ X2)

AND (|max_layers11-max_layers21| ≤ Y1)

-When the 1st CC and 2nd CC are set in FR2,

(|max_layers11-max_layers21| ≤ X2)

AND (|max_layers11-max_layers21| ≤ Y2)

-However, at least one of (X1> X2) and (Y1> Y2) must be satisfied.

As a specific example of applying the <Condition 3>, (X1, Y1, X2, Y2) = (4, 4, 2, 2) or (4, 4, 2, 0) or (4, 4, 0, 0) ) Or (4, 4, 2, 0) or (4, 0, 0, 0) or (2, 2, 2, 0) or (2, 2, 0, 0) or (2, 0, 0, 0 ), etc., can be applied.

As another embodiment, a description will be given of an operation when a different maximum number of layers is defined for each of the same band or CC according to a band combination, but the ambiguity is removed according to a system setting.

If the band combinations as shown in [Table 20] are defined, if CA is applied to Band1-CC1 and Band3-CC2, both band combination BC1 and band combination BC3 are possible. In this case, if the maximum number of layers max_layers is not clearly set, the maximum number of layers may be set according to a predetermined rule. For example, when the maximum value among the maximum number of layers values that can have each CC is used, (8, 2) may be set. On the other hand, if the minimum value is used, (4, 1) can be set.)

However, if CA is applied to Band1-CC1 and Band3-CC2, the maximum number of layers is clearly set for Band3-CC2 and transmitted through signaling information, the maximum value may be set differently. For example, if the base station clearly sets the maximum number of layers of Band3-CC2 to 2, since the band combination can determine that the band combination is BC3, the maximum number of layers of Band1-CC1 can be clearly set to 4.

Similarly, if CA is applied to Band1-CC1, Band2-CC2 and Band3-CC2, when the maximum number of layers of Band2-CC2 is clearly set to 8, it is confirmed that the band combination corresponds to the band combination BC1. Therefore, it can be clearly determined that the maximum number of layers of Band1-CC1 is 8 and the maximum number of layers of Band3-CC2 is 1.

On the contrary, if CA is applied to Band1-CC1, Band2-CC2 and Band3-CC2, when the maximum number of layers of Band2-CC2 is clearly set to 4, it is known that the band combination is BC2 or BC3. It can be clearly determined that the maximum number of layers for CC1 is 4, but it cannot be clearly determined whether the maximum number of layers for Band3-CC2 is 1 or 2. In this case, the maximum number of layers may be determined according to a predetermined rule. For example, the maximum number of layers may be determined as 2 when a rule is determined to be determined as a maximum value in advance, and 1 when a rule is determined to be determined as a minimum value.

In this way, when at least one maximum number of layers is determined for each specific band or CC, the maximum number of layers is clearly determined for each corresponding band or CC, and after determining whether there is ambiguity in the band combination for each other band or CC, the maximum layer A possible band combination is determined based on a fixed number of bands or CCs and the maximum number of layers, and if there is only one possible band combination, the maximum number of layers for each band or CC defined in the band combination is maximum. A method of determining or setting by the number of layers may be implemented. However, when there are two or more possible band combinations, the maximum number of layers for each band or for each CC may be set according to a predetermined rule.

If the maximum number of layers is clearly set for at least one or more bands or CCs, a method of determining the maximum number of layers for each band or CC may be expressed as follows. It is obvious that the following method can be applied even when the maximum number of layers for each band or CC is not set.

-Check the CC set (or reported) for the CA. (Identifying component-carriers (or bands) configured (or reported) for a carrier aggregation)

-Identifying the maximum number of layers for (corresponding to) at least a (or each) component carrier (or band));

-Check possible band combinations based on the identified maximum number of layers for each band or CC. (identifying possible (or candidate) band combinations based on the identified maximum number of layers for (corresponding to) the component carrier (or band));

-If the number of possible band combinations is one, the maximum number of layers that can be set according to the band combination is determined (or set or confirmed) as the maximum number of layers for each band or CC (for CCs other than the CC) . (in case that the number of possible band combinations is 1, determining the maximum number of layers corresponding to a component carrier (or band) different from the component carrier (or band) by the maximum number of layers configurable according to the band combination) ;

-When the number of possible band combinations is two or more, (for other CCs other than the CC) the maximum number of layers that can be set according to the band combination and a predetermined rule (e.g., (eg, set for each CC or band) (In case that the number of possible band combinations is larger than 1, determining the maximum number of layers per band or CC) based on the maximum or minimum possible number of layers). maximum number of layers corresponding to a component carrier (or band) different from the component carrier (or band) based on a predetermined rule (eg, max/min operation) and the numbers of layers configurable according to the band combinations);

Scheme for supporting terminals with low capability

When a terminal having a low capability accesses the base station, it is required to distinguish that the terminal has a low capability and/or to apply other system parameters to a terminal having a low capability. For example, a terminal having a low capability value may be an MTC terminal. Here, a terminal having a low capability value may be referred to as NR light or NR light, but the present invention is not limited thereto. For convenience of explanation, a terminal having a low capability value is referred to as a'low capability terminal', and a terminal having a capability that satisfies a requirement is referred to as a'general terminal'.

According to various embodiments, the system may define requirements for the terminal. For example, the requirements are to be able to transmit and receive in the entire frequency bandwidth operating in the frequency band to be accessed, to support 64-QAM, to support 4 layers in FR1, to support 2 layers in FR2, etc. It can be defined to include. However, such a requirement may increase the complexity of implementation of the terminal or increase the cost of implementing the terminal. In some cases, for example, depending on the type of service, ease of implementation, and the like, a terminal with lower capability than the requirements may access the base station. In this case, in order for the base station to support a low-capacity terminal, the following embodiments may be applied.

■ Provides separate system information

According to an embodiment, the base station may provide system information for a low capability terminal. For example, the base station may transmit a system information block (SIB) for a low capability terminal. In addition, the base station may include scheduling information on the SIB for the low capability terminal in a master information block (MIB) transmitted through a physical broadcast channel (PBCH). For example, the SIB for a low capability terminal may include at least one of parameters such as maxMIMO-Layers of PDSCH-ServingCellConfig, maxMIMO-Layers of PUSCH-ServingCellConfig, maxRank of pusch-Config, mcs-Table, mcs-TableTransformPrecoder have. In addition, the above-described parameters may be included in other signaling information or parameters.

■ Notification of low ability through random access procedure

According to an embodiment, the terminal may inform the base station that it has low capability. In the random access procedure performed by the terminal to access the base station, the terminal with low capability may be informed that the terminal has a capability lower than the system requirements. For example, low capability may be indicated by using a random access channel (RACH) preamble or by using a resource carrying a random access channel preamble. To this end, the base station may configure a preamble or resource for random access of a low-capacity terminal separately from resources for general terminals. Information on a preamble or resource for random access of a low capability terminal may be provided as system information (eg, SIB for a low capability terminal).

When recognizing that it is a low-capacity terminal, the base station may apply specific parameters for scheduling and signal transmission/reception for the corresponding terminal. For example, in the case of performing LBRM for the corresponding terminal, if the terminal does not set the maximum number of layers assumed or supported by the corresponding BWP from the base station, and also fails to exchange accurate terminal capability parameters with the base station , The base station may assume the maximum number of layers assumed or supported by the corresponding terminal in the corresponding BWP as a specific value. The maximum number of layers assumed for a low-capacity terminal may be a value different from that of general terminals.

For example, the maximum number of layers of the terminal used to calculate the TBS _LBRM is used as a value configured by the base station, but if there is no configuration by the base station, it can be used as the maximum number of layers supported by the terminal. If there is no exchange of the inter-terminal capability parameter, it can be used as a default value. In this case, it may be necessary to define a default value. In the case of a general terminal, the base station may calculate the TBS _LBRM assuming that the default value is 4 in FR1 and 2 in FR2. On the other hand, for a low-capacity terminal, the base station may assume a default value of 2 in FR1 and 1 in FR2. In addition, for a low-capacity terminal, a default value of the maximum modulation order Qm supported by the terminal, which is a parameter used for calculating the TBS _LBRM , may be defined as a value corresponding to 16-QAM. In addition, for a low-capacity terminal, a default value for scaling used for calculating a maximum data rate supported by the terminal may be defined as a value less than 1. In this way, the low-capacity terminal may be configured with a default value that is at least one or more different from some parameter values set in the general terminal, and the configured value may correspond to a case that supports lower capabilities than the general terminal.

Uplink LBRM implementation plan

Various embodiments to be described later are for efficient uplink LBRM (eg, UL-SCH LBRM or PUSCH LBRM) in transmitting data. When PUSCH-LBRM is applied, the TBS _LBRM may be determined based on the following settings.

[Setting A for rate matching considering PUSCH-LBRM]

The maximum number of layers X for one TB may be determined as follows. (maximum number of layers for one TB for UL-SCH is given by X, where)

Settings Contents 0 When the parameter maxMIMO-Layers-BWP included in the higher layer signaling PUSCH-ServingCellConfigBWP for all BWPs of the serving cell is configured (configured), X is determined based on the maximum value among maxMIMO-Layers-BWP for each BWP. (If the higher layer parameters maxMIMO-Layers-BWP of PUSCH-ServingCellConfigBWP of all BWPs of the serving cell are configured, X is given by the maximum value among maxMIMO-Layers-BWP) One When the parameter maxMIMO-Layers included in the higher layer signaling PUSCH-ServingCellConfig is configured, X is determined based on the parameter maxMIMO-Layers. (else if the higher layer parameter maxMIMO-Layers of PUSCH-ServingCellConfig of the serving cell is configured, X is given by that parameter) 2 If maxMIMO-Layers is not set and the parameter maxRank included in the upper layer signaling pusch-Config is configured, the maximum value is determined as an X value among maxRank values defined over all BWPs of the serving cell. (else if the higher layer parameter maxRank of pusch-Config of the serving cell is configured, X is given by the maximum value of maxRank across all BWPs of the serving cell) 3 If it does not correspond to setting 0, setting 1, and setting 2, the maximum number of layers for the PUSCH supported by the UE in the serving cell is determined as X. (otherwise, X is given by the maximum number of layers for PUSCH supported by the UE for the serving cell)

In the embodiment of [Table 21], when the maximum number of layers is configured for a plurality of BWPs, X is determined as the maximum value among the maximum number of layers. According to another embodiment, X may be determined as a minimum value among the maximum number of layers. According to another embodiment, X may be determined as a value (eg, a median value, an average value, etc.) determined based on the maximum number of layers.

In addition, in the embodiment of [Table 21], when maximum ranks are configured for a plurality of BWPs, X is determined as the maximum value among the maximum ranks. According to another embodiment, X may be determined as the minimum value among the maximum ranks. According to another embodiment, X may be determined as a value (eg, a median value, an average value, etc.) determined based on the maximum ranks.

In the embodiment of [Table 21], setting 0 and setting 2 determine X based on all BWPs of the serving cell. However, according to another embodiment, X may be determined based on all active BWPs, or active BWPs, or all configured BWPs according to the system. According to another embodiment, X may be determined based on a plurality of BWPs that are used or satisfy a specific condition.

Operations of the terminal for the above configuration for PUSCH-LBRM are described below with reference to FIGS. 13 and 14.

13 is a flowchart 1300 of a terminal for determining the maximum number of layers in a wireless communication system according to various embodiments of the present disclosure. 13 illustrates an operation method of the terminal 120.

Referring to FIG. 13, in step 1301, the UE receives an indication for PUSCH-LBRM. In step 1303, the terminal checks whether the parameter maxMIMO-Layers-BWP is configured. Here, the parameter maxMIMO-Layers-BWP may be configured for each BWP for at least one BWP. If the parameter maxMIMO-Layers-BWP is configured, in step 1305, the UE determines X based on maxMIMO-Layers-BWP values for each BWP. For example, X may be determined as any one of a maximum value, a minimum value, an average value, and a median value of maxMIMO-Layers-BWP values. In this case, the considered BWPs may be all BWPs, activated BWPs, or BWPs that satisfy a specific condition.

If the parameter maxMIMO-Layers-BWP is not configured, in step 1307, the terminal checks whether the parameter maxMIMO-Layer is configured. If maxMIMO-Layer is configured, in step 1309, the UE determines X as the value of maxMIMO-Layer. On the other hand, if maxMIMO-Layer is not configured, in step 1311, the terminal checks whether the parameter maxRank is set. If maxRank is configured, in step 1313, the UE determines the maximum value of maxRank for all BWPs of the serving cell as X. On the other hand, if maxRank is not configured, in step 1315, the UE determines the maximum number of layers for the PUSCH supported by the UE in the serving cell as X.

14 is another flowchart 1400 of a terminal for determining the maximum number of layers in a wireless communication system according to various embodiments of the present disclosure. 14 illustrates a method of operating the terminal 120. 14 illustrates an embodiment excluding steps 1303 and 1305 from the embodiment of FIG. 13. The embodiment of FIG. 14 may be applied when the parameter maxMIMO-Layers value included in the PUSCH-ServingCellConfig configured in the base station is the same as the maxRank value included in the pusch-Config.

Referring to FIG. 14, in step 1401, the UE receives an indication for PUSCH-LBRM. In step 1403, the terminal checks whether the parameter maxMIMO-Layers-BWP is configured. Here, the parameter maxMIMO-Layers-BWP may be configured for each BWP for at least one BWP. If the parameter maxMIMO-Layers-BWP is configured, in step 1405, the UE determines X based on maxMIMO-Layers-BWP values for each BWP. For example, X may be determined as any one of a maximum value, a minimum value, an average value, and a median value of maxMIMO-Layers-BWP values. In this case, the considered BWPs may be all BWPs, activated BWPs, or BWPs that satisfy a specific condition.

If the parameter maxMIMO-Layers-BWP is not configured, in step 1407, the terminal checks whether the parameter maxRank is set. If maxRank is set, in step 1409, the UE determines the maximum value of maxRank for all BWPs of the serving cell as X. On the other hand, if maxRank is not set, in step 1411, the UE determines the maximum number of layers for the PUSCH supported by the UE in the serving cell as X.

When the rate matching process in consideration of the above-described PUSCH-LBRM is reorganized, it is obvious that the changed setting as follows may be applied.

[Setting B for rate matching considering PUSCH-LBRM]

The maximum number of layers X for one TB may be determined as follows. (maximum number of layers for one TB for UL-SCH is given by X, where)

Settings Contents 0 When the parameter maxMIMO-Layers-BWP included in the higher layer signaling PUSCH-ServingCellConfigBWP for all BWPs of the serving cell is configured, X is determined as the maximum value among maxMIMO-Layers-BWP for each BWP (If the higher layer parameters maxMIMO-Layers-BWP of PUSCH-ServingCellConfigBWP of all BWPs of the serving cell are configured, X is given by the maximum value among maxMIMO-Layers-BWP) One When the parameter maxRank included in the higher layer signaling pusch-Config is set, the maximum value is determined as an X value among maxRank values defined over all BWPs of the serving cell. (else if the higher layer parameter maxRank of pusch-Config of the serving cell is configured, X is given by the maximum value of maxRank across all BWPs of the serving cell) 2 If it does not correspond to setting 0 and setting 1, the maximum number of layers for the PUSCH supported by the UE in the serving cell is determined as X. (otherwise, X is given by the maximum number of layers for PUSCH supported by the UE for the serving cell)

In the embodiment of [Table 22], when the maximum number of layers is configured for a plurality of BWPs, X is determined as the maximum value among the maximum number of layers. According to another embodiment, X may be determined as a minimum value among the maximum number of layers. According to another embodiment, X may be determined as a value (eg, a median value, an average value, etc.) determined based on the maximum number of layers.

In addition, in the embodiment of [Table 22], when maximum ranks are configured for a plurality of BWPs, X is determined as the maximum value among the maximum ranks. According to another embodiment, X may be determined as the minimum value among the maximum ranks. According to another embodiment, X may be determined as a value (eg, a median value, an average value, etc.) determined based on the maximum ranks.

In addition, setting 0 and setting 2 of the embodiment of [Table 17] determine X based on all BWPs (all BWPs) of the serving cell, but more specifically, depending on the system, all active BWPs (all active BWPs) or all set BWPs (all configured BWPs) may be used as a reference or a plurality of BWPs that satisfy a specific condition may be used as a reference.

For reference, in the embodiments of [Table 21] and [Table 22], a system in which signaling information including maxMIMO-Layers-BWP is PUSCH-ServingCellConfigBWP has been described, but the name or parameter of such signaling information is generally communicated. It may be set to a different name according to the system or version information of the system.

According to another embodiment, for rate matching in consideration of PUSCH-LBRM, parameters are set in consideration of a band combination and a feature set related to at least one serving cell (or configured (or configured) at least one serving cell) Can be. For example, the maximum number of layers may be determined in consideration of any signaled or indicated band combination and function set related to the serving cell. An embodiment of this will be described in [Setting C for Rate Matching Considering PUSCH-LBRM].

[Setting C for rate matching considering PUSCH-LBRM]

The maximum number of layers X for one TB is determined as follows. (maximum number of layers for one TB for UL-SCH is given by X, where)

Settings Contents 0 When the parameter maxMIMO-Layers included in the higher layer signaling PUSCH-ServingCellConfig is configured, X is determined as the parameter maxMIMO-Layers. (if the higher layer parameter maxMIMO-Layers of PUSCH-ServingCellConfig of the serving cell is configured, X is given by that parameter) One If the maxMIMO-Layers is not set and the parameter maxRank included in the upper layer signaling pusch-Config is set, the maximum value among maxRank values defined over all BWPs of the serving cell is determined as the X value. (elseif the higher layer parameter maxRank of pusch-Config of the serving cell is configured, X is given by the maximum value of maxRank across all BWPs of the serving cell) 2 If it does not correspond to setting 0 and setting 1, the maximum number of layers for the PUSCH supported by the UE delivered in a combination of bands related to the serving cell and feature set is determined as X. (otherwise, X is given by the maximum number of layers for PUSCH supported by the UE for any signaled band combination and feature set consistent with the serving cell)

In setting 2 of [Table 23], since the UE does not have a common understanding of the currently applied band combination with the base station, X may be determined as the largest number of supported layers in consideration of all band combinations.

For successful decoding, the rate matching schemes in consideration of the LBRM described above will have to maintain the same configuration or a promised configuration for both the base station and the terminal or the transmitter and the receiver. At this time, it is obvious that various combinations of the components mentioned in the present disclosure are possible.

Downlink LBRM implementation plan

Various embodiments described below are for efficient downlink LBRM (eg, PDSCH-LBRM, DL-SCH LBRM, or PCH LBRM) in transmitting data. Hereinafter, the present disclosure describes an embodiment of a PDSCH-LBRM, but the described embodiment may be applied to a DL-SCH LBRM or a PCH LBRM.

The TBS _LBRM is determined based on the maximum number of layers of PUSCH or PDSCH set in higher layer signaling (eg, RRC signaling). However, until information on UE capability is reported from the UE to the base station, since the maximum number of layers is not determined, there may be a problem in applying the LBRM.

15 illustrates an example of a section in which ambiguity of a parameter required to perform LBRM occurs in a wireless communication system according to various embodiments of the present disclosure. 15 is an example of events occurring during an initial access process of a terminal. Referring to FIG. 15, an SS/PBCH is detected at a first time point 1510, a RACH procedure is completed at a second time point 1520, a UE dynamics information is requested at a third time point 1530, and a fourth time point. In 1540, the UE capability information is reported.

During the period 1550 between the second view 1520 and the fourth view 1540, there is a possibility that the settings for the maximum number of layers of PUSCH or PDSCH between the base station and the terminal are different from each other. In this case, PUSCH decoding at the base station may not be properly performed, and PDSCH decoding at the terminal may not be properly performed. In other words, since the UE cannot decode the PDSCH immediately after the RACH procedure, the UE may not receive any RRC message. Therefore, until the UE capability is reported to the base station, a rule between the base station and the UE for determining the maximum number of layers of PUSCH or PDSCH is required.

As one of the solutions to the above problem, it may be considered to fix the value of the maximum number of layers X to a predetermined value (a predetermined value or integer) during the period 1050 of FIG. 15. For example, a specific integer such as X = 1 or X = 2 is used, or a specific value mandated to the UE as the maximum mumber of layers in the band, etc. It can be defined to decide. In the following examples, X = 1 is illustrated, but the present invention is not limited thereto.

[Setting A for rate matching considering PDSCH-LBRM]

The maximum number of layers for one TB is determined as the minimum value among the following X and 4. (maximum number of layers for one TB for DL-SCH/PCH is given by the minimum of X and 4, where)

Settings Contents 0 When the parameter maxMIMO-Layers-BWP included in the higher layer signaling PDSCH-ServingCellConfigBWP for all BWPs of the serving cell is configured, X is determined as the maximum value among maxMIMO-Layers-BWP for each BWP. (If the higher layer parameters maxMIMO-Layers-BWP of PDSCH-ServingCellConfigBWP of all BWP of the serving cell are configured, X is given by the maximum value among maxMIMO-Layers) One When the parameter maxMIMO-Layers included in the higher layer signaling PDSCH-ServingCellConfig is configured, X is determined as the parameter maxMIMO-Layers. (else if the higher layer parameter maxMIMO-Layers of PDSCH-ServingCellConfig of the serving cell is configured (or given), X is given by that parameter) 2 If the maxMIMO-Layers is not set and the parameter maxNumberMIMO-Layers-PDSCH of higher layer signaling is set, X is determined as the parameter maxNumberMIMO-Layers-PDSCH. (else if the higher layer parameter maxNumberMIMO-LayersPDSCH is configured ( or given), X is given by that parameter) 3 If setting 0, setting 1 and setting 2 are not applicable, set X = 1. (otherwise, X = 1)

According to another embodiment, setting 2 in [Table 24] may be replaced with a condition as shown in [FIG. 20] below.

Settings Contents 2 -If the higher layer parameters maxMIMO-Layers-BWP of PDSCH-ServingCellConfigBWP of all BWPs of the serving cell are configured, X is given by the maximum value among maxMIMO-Layers.- else if the higher layer parameter maxNumberMIMO-LayersPDSCH is configured ( or given), X is given by the maximum number of layers for PDSCH supported by the UE for the serving cell.

In setting 3 of [Table 24], X may be set to an integer different from 1 or may be set to a different parameter. For reference, in the embodiment of [Table 23] or [19], the process of determining X based on all BWPs (all BWPs) of the serving cell is more specifically according to the system, or all active BWPs (all active BWPs) or all It is also possible to use a set BWP (all configured BWPs) as a reference or use a plurality of BWPs that satisfy a specific condition as a reference. For reference, in the embodiments of [Table 23] and [Table 24], a system in which signaling information including maxMIMO-Layers-BWP is PDSCH-ServingCellConfigBWP has been described, but the name or parameter of such signaling information is generally communicated. It may be set to a different name according to the system or version information of the system.

The operation of the terminal according to the rules shown in [Table 24] is shown in FIG. 16 below.

16 illustrates another flowchart 1600 of a terminal for determining the maximum number of layers in a wireless communication system according to various embodiments of the present disclosure. 16 illustrates an operation method of the terminal 120.

Referring to FIG. 16, in step 1601, the UE receives an indication for PDSCH-LBRM. In step 1603, the terminal checks whether the parameter maxMIMO-Layers-BWP is configured. Here, the parameter maxMIMO-Layers-BWP may be configured for each BWP for at least one BWP. If the parameter maxMIMO-Layers-BWP is configured, in step 1605, the UE determines X based on maxMIMO-Layers-BWP values for each BWP. For example, X may be determined as any one of a maximum value, a minimum value, an average value, and a median value of maxMIMO-Layers-BWP values. In this case, the considered BWPs may be all BWPs, activated BWPs, or BWPs that satisfy a specific condition.

If the parameter maxMIMO-Layers-BWP is not configured, in step 1607, the UE checks whether the parameter maxMIMO-Layer is set. If maxMIMO-Layer is configured, in step 1609, the UE determines X as the value of maxMIMO-Layer. On the other hand, if maxMIMO-Layer is not set, in step 1611, the UE checks whether the parameter maxNumberMIMO-LayersPDSCH is set. If maxNumberMIMO-LayersPDSCH is configured, in step 1613, the UE determines X as the value of maxNumberMIMO-LayersPDSCH. On the other hand, if maxNumberMIMO-LayersPDSCH is not set, in step 1615, the UE determines X with a predetermined value (eg, 1).

According to another embodiment, parameters may be set in consideration of a band combination and a function set associated with at least one serving cell (or at least one configured serving cell) for rate matching in consideration of PDSCH-LBRM. For example, in determining the maximum number of layers, the maximum number of layers may be determined in consideration of any signaled or indicated band combination and function set related to the serving cell. An embodiment of this will be described in the following [Configuration B for Rate Matching Considering PDSCH-LBRM].

[Setting B for rate matching considering PDSCH-LBRM]

The maximum number of layers for one TB is determined as the minimum value among the following X and 4. (maximum number of layers for one TB for DL-SCH/PCH is given by the minimum of X and 4, where)

Settings Contents One When the parameter maxMIMO-Layers included in the higher layer signaling PDSCH-ServingCellConfig is configured, X is determined as the number of maxMIMO-Layers. (if the higher layer parameter maxMIMO-Layers of PDSCH-ServingCellConfig of the serving cell is configured, X is given by that parameter) 2 If it does not correspond to configuration 1, the maximum number of layers for the PDSCH supported by the UE delivered in the band combination and feature set related to the serving cell is determined as X. (otherwise, X is given by the maximum number of layers for PDSCH supported by the UE for any signaled band combination and feature set consistent with the serving cell)

In setting 2 of [Table 26], since the UE does not have a common understanding of the currently applied band combination with the base station, X may be determined as the largest number of supported layers in consideration of all band combinations.

A specific embodiment of parameter setting for applying the LBRM of the present invention may be expressed as follows.

[Setting C for rate matching considering PDSCH-LBRM]

Configuration 1: When maxNumberMIMO-LayersPDSCH is set in higher layer signaling, the maximum number of layers (v) for one TB is set to a smaller value (or less than or equal to) of the two by comparing maxNumberMIMO-LayersPDSCH and 4. If maxNumberMIMO-LayersPDSCH is not set, the maximum number of layers for one TB is set to 1.

로 가정한다. 그렇지 않으면

으로 가정한다.Setting 2: In higher layer signaling, if mcs-Table is set to qam256, the maximum modulation order is

Is assumed. Otherwise

Is assumed.

Setting 3: The maximum code rate is set to R=948/1024.

Setting 4: Set NRE = 156*N _{PRB, LBRM} . However, the N _{PRB, LBRM} value means the maximum number of PRBs across all configured BWPs of a carrier.

The above-described settings can be expressed as follows.

- if maxNumberMIMO-LayersPDSCH provided,

v = min (maxNumberMIMO-LayersPDSCH, 4);

else

v = 1;

- if mcs-Table = qam256,

Qm = 8;

else

Qm = 6;

- R = 948/1024;

- NRE = 156*NPRB,LBRM

If a parameter necessary to determine the maximum number of layers for one TB is set in higher layer signaling, such as the above-described [Setting C for rate matching considering PDSCH-LBRM] , the maximum number of layers will be determined based on the set value. I can. However, if the corresponding parameters are not set in higher layer signaling, the maximum number of layers is set to a predetermined value (e.g., v = 1 or 2 or 3 or ??), or determined according to a predetermined rule. Can be set by value.

Similarly, if parameters necessary for determining the maximum modulation order are set in higher layer signaling, the maximum modulation order may be determined based on the set value. However, when corresponding parameters are not set in higher layer signaling, the maximum modulation order may be set to a predetermined value or a value determined according to a predetermined rule.

In addition, conditions for the mcs-Table may be modified in various forms. For example, according to the BWP of the serving cell, the maximum modulation order may be set according to whether qam256 is set in the mcs-Table. For example, set Qm = 8 if qam256 is set for mcs-Tables for one or more BWPs, or Qm = 8 if qam256 is set for mcs-Tables for all BWPs. A variety of methods can be implemented, such as. In addition, a similar method may be implemented based on a value such as mcs-TableTransformPrecoder instead of mcs-Table.

The various embodiments described above have been described centering on the operation of the terminal. However, for encoding or decoding to which the LBRM is applied in the base station, the base station may also perform encoding or decoding after performing the same parameter setting operation corresponding to the terminal. In this case, the operation of the base station is similar to that of the terminal described above. In addition, it is obvious that various combinations of the PUSCH-LBRM method and PDSCH-LBRM operation proposed in the present disclosure can be applied to the LBRM method of the base station and the terminal. In other words, in using the rate matching schemes in consideration of the LBRM described above for successful decoding, the base station and the terminal, or the transmitter and the receiver must all maintain the same or promised configuration. At this time, it is obvious that various combinations of the components mentioned in the present disclosure are possible.

In general, LBRM may affect performance because part of parity may not be transmitted due to buffer constraints. For this reason, the base station or the terminal may set the MCS so that the LBRM is not applied or minimized as much as possible. For example, after calculating the TBS for each MCS, the base station or the terminal may determine whether to apply LBRM in cases of scheduling with each MCS, and may not use the MCS determined to be applied LBRM. In other words, the base station or the terminal may use one MCS among MCSs to which LBRM is not applied. In some cases, even if LBRM is applied, in order to minimize its effect, the base station or the terminal may set a relatively high or highest MCS among MCSs to which LBRM is applied as the final MCS. Here, whether to apply the LBRM may be determined by comparing the N value and the N _ref value for each MCS. For example, if N> N _ref, LBRM is applied, otherwise LBRM may not be applied.

As described above, the method of controlling the application of LBRM through MCS setting may be applied differently according to the operation of stand-alone (SA) or non-stand alone (NSA) in the system after 5G. In the case of a communication system or network to which the SA operation method is applied, the application of LBRM is controlled through the MCS setting, but in the case of a communication system or network to which the NSA operation method is applied, the application of LBRM through the MCS setting is not applied. I can. Conversely, in the case of a communication system or network to which the NSA operation method is applied, the application of LBRM is controlled through MCS setting, but in the case of a communication system or network to which the SA operation method is applied, the application of LBRM through MCS setting is applied. It can not be. In addition, the application of LBRM is controlled through MCS configuration for both SA/NSA operation methods, but specific rules may be defined differently. Here, SA operation is a method in which a first cellular network (eg, a legacy network) and a second cellular network (eg, a 5G network) operate independently, and in the NSA operation, the first cellular network and the second cellular network are connected to each other. It is a method of being operated. When two networks are connected and operated, it means that at least one network controls the operation of another network.

The methods according to the embodiments described in the claims or the specification of the present disclosure may be implemented in the form of hardware, software, or a combination of hardware and software.

When implemented in software, a computer-readable storage medium storing one or more programs (software modules) may be provided. One or more programs stored in a computer-readable storage medium are configured to be executable by one or more processors in an electronic device (device). The one or more programs include instructions that cause the electronic device to execute methods according to embodiments described in the claims or specification of the present disclosure.

These programs (software modules, software) include random access memory, non-volatile memory including flash memory, read only memory (ROM), and electrically erasable programmable ROM. (electrically erasable programmable read only memory, EEPROM), magnetic disc storage device, compact disc-ROM (CD-ROM), digital versatile discs (DVDs) or other forms of It may be stored in an optical storage device or a magnetic cassette. Alternatively, it may be stored in a memory composed of a combination of some or all of them. In addition, a plurality of configuration memories may be included.

In addition, the program is through a communication network composed of a communication network such as the Internet, an intranet, a local area network (LAN), a wide area network (WAN), or a storage area network (SAN), or a combination thereof. It may be stored in an attachable storage device that can be accessed. Such a storage device may be connected to a device performing an embodiment of the present disclosure through an external port. In addition, a separate storage device on the communication network may access a device performing an embodiment of the present disclosure.

In the above-described specific embodiments of the present disclosure, components included in the disclosure are expressed in the singular or plural according to the presented specific embodiments. However, the singular or plural expression is selected appropriately for the situation presented for convenience of description, and the present disclosure is not limited to the singular or plural constituent elements, and even constituent elements expressed in plural are composed of the singular or in the singular. Even the expressed constituent elements may be composed of pluralities.

Meanwhile, although specific embodiments have been described in the detailed description of the present disclosure, various modifications are possible without departing from the scope of the present disclosure. Therefore, the scope of the present disclosure is limited to the described embodiments and should not be determined, and should be determined by the scope of the claims as well as the equivalents of the claims to be described later.

Claims (20)

In the method of operating a terminal in a wireless communication system,
The process of receiving an indication for limited buffer rate matching (LBRM) from the base station, and
A process of obtaining at least one parameter necessary to perform the LBRM, and
A process of determining a limited range of parity bits for the LBRM based on the parameters, and
And transmitting or receiving data based on the limited range.
The method according to claim 1,
The at least one parameter includes at least one parameter for calculating a TB (tansport block) size,
At least one parameter for calculating the TB size includes at least one of a maximum number of layers and a band combination applied for carrier aggregation (CA).
The method according to claim 1,
The process of obtaining at least one parameter,
A method comprising receiving an indicator indicating a band combination applied to perform carrier aggregation (CA).
The method according to claim 1,
The process of obtaining at least one parameter,
A method comprising the process of determining a value for determining the limited range as the maximum number of layers that can be supported by a carrier used for carrier aggregation (CA).
The method according to claim 1,
The process of obtaining at least one parameter,
A method comprising the step of determining a value for determining the limited range as a value determined based on the maximum number of layers configured for a plurality of bandwidth parts (BWP).
The method of claim 5,
A value determined based on the maximum number of layers,
A method including one of a maximum value or a minimum value among the maximum number of layers.
The method of claim 5,
The process of obtaining at least one parameter,
If the maximum number of layers of a plurality of bandwidth parts (BWP) is not configured, a process of determining a value for determining the limited range as the maximum number of layers configured for a serving cell;
If the maximum number of layers is not configured for the serving cell, a process of determining a value for determining the limited range with a value determined based on the maximum ranks configured for the plurality of BWPs. How to.
The method of claim 7,
A value determined based on the maximum ranks,
A method comprising one of a maximum value or a minimum value among the maximum ranks.
The method of claim 5,
The process of obtaining at least one parameter,
If the maximum number of layers of a plurality of bandwidth parts (BWP) is not configured, a method comprising a process of determining a value for determining the limited range with a value determined based on the maximum ranks configured for a channel .
The method of claim 5,
The process of obtaining at least one parameter,
If the maximum number of layers of a plurality of bandwidth parts (BWP) is not configured, a process of determining a value for determining the limited range as the maximum number of layers configured for a serving cell;
And if the maximum number of layers is not configured for the serving cell, determining a value for determining the limited range with a predetermined value.
In a terminal in a wireless communication system,
Transceiver and,
And at least one processor connected to the transceiver,
The at least one processor,
Receiving an indication for LBRM (limited buffer rate matching) from the base station,
Obtaining at least one parameter necessary to perform the LBRM,
Determine a limited range of parity bits for the LBRM based on the parameters,
A terminal that transmits or receives data based on the limited range.
The method of claim 11,
The at least one parameter includes at least one parameter for calculating a TB (tansport block) size,
At least one parameter for calculating the TB size includes at least one of a maximum number of layers and a band combination applied for carrier aggregation (CA).
The method of claim 11,
The at least one processor is a terminal receiving an indicator indicating a band combination applied to perform carrier aggregation (CA).
The method of claim 11,
The at least one processor determines a value for determining the limited range with the maximum number of layers supported by a carrier used for carrier aggregation (CA).
The method of claim 11,
The process of obtaining at least one parameter,
A terminal that determines a value for determining the limited range with a value determined based on the maximum number of layers configured for a plurality of bandwidth parts (BWP).
The method of claim 15,
A value determined based on the maximum number of layers includes one of a maximum value or a minimum value among the maximum number of layers.
The method of claim 15,
The at least one processor,
If the maximum number of layers of a plurality of bandwidth parts (BWP) is not configured, a value for determining the limited range is determined as the maximum number of layers configured for a serving cell,
When the maximum number of layers is not configured for the serving cell, the terminal determines a value for determining the limited range with a value determined based on maximum ranks configured for the plurality of BWPs.
The method of claim 17,
The value determined based on the maximum ranks includes one of a maximum value or a minimum value among the maximum ranks.
The method of claim 15,
The at least one processor,
When the maximum number of layers of a plurality of bandwidth parts (BWP) is not configured, a terminal determining a value for determining the limited range with a value determined based on maximum ranks configured for a channel.
The method of claim 15,
The at least one processor,
If the maximum number of layers of a plurality of bandwidth parts (BWP) is not configured, a value for determining the limited range is determined as the maximum number of layers configured for a serving cell,
If the maximum number of layers is not configured for the serving cell, the terminal determines a value for determining the limited range with a predetermined value.

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