User equipment, base stations, and their operation methods in wireless communication systems

Abstract

A method performed by a user equipment (UE) in a wireless communication system, the method comprising: receiving configuration information from a base station (BS) via radio resource control (RRC) signaling for indicating one of a plurality of modulation and coding scheme (MCS) tables, wherein the plurality of MCS tables includes: a first MCS table including a plurality of MCS indices; and a second MCS table including a plurality of MCS indices, wherein the method further comprises: identifying an MCS index from the second MCS table if the configuration information indicates the second MCS table; and receiving data using the identified MCS index, wherein the first MCS index of the first MCS table indicating a first modulation scheme and a first code rate is lower than the second MCS index of the second MCS table indicating the first modulation scheme and the first code rate, and wherein the first MCS table and the second MCS table include the same maximum modulation order.

Description

[0001] This application is a divisional application, with parent application number 201880074175.3, application date November 16, 2018, and invention title: Apparatus and method for transmitting control information in a communication system. Technical Field

[0002] This disclosure relates generally to communication systems, and more specifically to apparatus and methods for transmitting and receiving control information in a communication system. Background Technology

[0003] To meet the growing demand for wireless data services following the commercialization of fourth-generation (4G) communication systems, efforts have been made to develop advanced fifth-generation (5G) communication systems or pre-5G communication systems. For this reason, 5G or pre-5G communication systems are referred to as beyond-4G network communication systems or post-Long Term Evolution (LTE) systems.

[0004] To achieve high data rates, 5G communication systems are considering implementation in extremely high frequency (mmWave) bands (e.g., the 60 GHz band). To mitigate propagation path loss and extend propagation distance in these ultra-high frequency bands, beamforming, massive multiple input multiple output (MIMO), full-dimensional (FD)-MIMO, array antennas, analog beamforming, and massive MIMO technologies are being discussed for 5G communication systems.

[0005] In addition, to enhance the network performance of the system, 5G communication systems are developing technologies such as evolved small cells, advanced small cells, cloud radio access network (RAN), ultra-dense networks, device-to-device communication (D2D), wireless backhaul, mobile networks, cooperative communication, coordinated multi-point (CoMP), and receive interference cancellation.

[0006] In addition, 5G systems are researching hybrid frequency-shift keying (FSK), quadrature amplitude modulation (QAM) (FQAM), and sliding window superposition coding (SWSC) as advanced coding modulation (ACM) schemes, as well as filter bank multicarrier (FBMC), non-orthogonal multiple access (NOMA), and sparse code multiple access (SCMA) as advanced access technologies.

[0007] Meanwhile, the new radio (NR) for 5G communication is designed to freely multiplex various services in time and frequency resources, and correspondingly, waveform / parameter sets and reference signals can be dynamically or freely allocated based on the needs of the corresponding service. Optimized data transmission through measuring channel quality and interference is crucial for providing the best service to terminals in communication; therefore, accurate channel state measurement is necessary. However, unlike 4G communication, where channel and interference characteristics do not change significantly with frequency resources, the channel and interference characteristics in 5G channels change significantly with service. Therefore, it is necessary to support subsets of the frequency resource group (FRG) for partitioning and measuring them. Furthermore, the service types supported in the NR system can be categorized into classes such as enhanced mobile broadband (eMBB), massive machine-type communication (mMTC), and ultra-reliable and low-latency communication (URLLC). eMBB can be a service designed for high-speed transmission of high-capacity data, mMTC can be a service designed for minimizing terminal power and enabling multiple terminal accesses, and URLLC can be a service designed for high reliability and low latency. Different requirements can be applied depending on the type of service applied to the terminal.

[0008] As mentioned above, multiple services can be provided to users in a communication system, and what is needed is a method for providing each feature of the service to the user within the same time period, as well as an apparatus for using the method. Summary of the Invention

[0009] Technical issues

[0010] Based on the above discussion, this disclosure provides an apparatus and method for generating a channel quality indicator (CQI) and modulation and coding scheme (MCS) table in a wireless communication system requiring various block error rate (BLER) targets.

[0011] Solution to the problem

[0012] According to various embodiments of this disclosure, an operation method for user equipment (UE) in a communication system includes: performing radio resource control (RRC) signaling with a base station; determining a code rate based on an RRC configuration according to the RRC signaling; and using the code rate to determine the size of data.

[0013] According to various embodiments of this disclosure, a UE device in a communication system includes a transceiver and at least one processor functionally coupled to the transceiver. The at least one processor performs RRC signaling with a base station, determines a code rate based on an RRC configuration according to the RRC signaling, and uses the code rate to determine the size of the data.

[0014] According to one aspect of this disclosure, a method performed by a user equipment (UE) in a wireless communication system is provided, the method comprising: receiving configuration information from a base station (BS) via radio resource control (RRC) signaling for indicating one of a plurality of modulation and coding scheme (MCS) tables, wherein the plurality of MCS tables includes: a first MCS table including a plurality of MCS indices; and a second MCS table including a plurality of MCS indices, wherein the method further comprises: identifying an MCS index from the second MCS table if the configuration information indicates the second MCS table; and receiving data using the identified MCS index, wherein the first MCS index of the first MCS table indicating a first modulation scheme and a first code rate is lower than the second MCS index of the second MCS table indicating the first modulation scheme and the first code rate, and wherein the first MCS table and the second MCS table include the same maximum modulation order.

[0015] According to one aspect of this disclosure, a user equipment (UE) in a wireless communication system is provided, comprising: at least one transceiver; and at least one processor operatively connected to the at least one transceiver; wherein the at least one processor is configured to: receive configuration information from a base station (BS) via radio resource control (RRC) signaling for indicating one of a plurality of modulation and coding scheme (MCS) tables, wherein the plurality of MCS tables includes: a first MCS table including a plurality of MCS indices; and a second MCS table including a plurality of MCS indices, wherein the at least one processor is further configured to: identify an MCS index from the second MCS table if the configuration information indicates the second MCS table; and receive data using the identified MCS index, wherein the first MCS index of the first MCS table indicating a first modulation scheme and a first code rate is lower than the second MCS index of the second MCS table indicating the first modulation scheme and the first code rate, and wherein the first MCS table and the second MCS table include the same maximum modulation order.

[0016] According to one aspect of this disclosure, a method performed by a base station (BS) in a wireless communication system is provided, the method comprising: transmitting configuration information to a user equipment (UE) via radio resource control (RRC) signaling for indicating one of a plurality of modulation and coding scheme (MCS) tables, wherein the plurality of MCS tables includes: a first MCS table including a plurality of MCS indexes; and a second MCS table including a plurality of MCS indexes, wherein the method further comprises using the configuration information to transmit data, wherein a first MCS index of the first MCS table indicating a first modulation scheme and a first code rate is lower than a second MCS index of the second MCS table indicating the first modulation scheme and the first code rate, and wherein the first MCS table and the second MCS table include the same maximum modulation order.

[0017] According to one aspect of this disclosure, a base station (BS) in a wireless communication system is provided, comprising: at least one transceiver; and at least one processor operatively connected to the at least one transceiver; wherein the at least one processor is configured to transmit configuration information to a user equipment (UE) via radio resource control (RRC) signaling for indicating one of a plurality of modulation and coding scheme (MCS) tables, wherein the plurality of MCS tables includes: a first MCS table including a plurality of MCS indices; and a second MCS table including a plurality of MCS indices, wherein the at least one processor is further configured to use the configuration information to transmit data, wherein a first MCS index of the first MCS table indicating a first modulation scheme and a first code rate is lower than a second MCS index of the second MCS table indicating the first modulation scheme and the first code rate, and wherein the first MCS table and the second MCS table include the same maximum modulation order.

[0018] Beneficial effects of the invention

[0019] The apparatus and methods according to various embodiments of this disclosure can use multiple Channel Quality Indicators (CQI) and Modulation and Coding Scheme (MCS) tables to support various scenarios to improve system transmission efficiency and effectively obtain the transport block size (TBS).

[0020] The effects that can be obtained from this disclosure are not limited to those described above, and other effects not mentioned will be clearly understood by those skilled in the art from the following description. Attached Figure Description

[0021] Figure 1 Wireless communication systems according to various embodiments of the present disclosure are shown.

[0022] Figure 2 The configuration of a base station in a wireless communication system according to various embodiments of the present disclosure is shown.

[0023] Figure 3 The configuration of a terminal in a wireless communication system according to various embodiments of the present disclosure is shown.

[0024] Figures 4A to 4C The configuration of a communication unit in a wireless communication system according to various embodiments of the present disclosure is shown.

[0025] Figure 5 The basic structure of the frequency-time domain according to various embodiments of the present disclosure is shown. This frequency-time domain is a radio resource area used to transmit data or control information in the downlink of a Long Term Evolution (LTE) system.

[0026] Figure 6 Modulation schemes that can be used in wireless communication systems according to various embodiments of the present disclosure are shown.

[0027] Figure 7 Examples of a Channel Quality Indicator (CQI) transmission based on channel state information of the terminal, which is measured by the terminal, according to various embodiments of the present disclosure.

[0028] Figure 8 A flowchart is shown of a terminal for calculating the Transport Block Size (TBS) using CQI and MCS tables, according to various embodiments of the present disclosure.

[0029] Figure 9 Another flowchart is shown for a terminal for calculating TBS using CQI and MCS tables according to various embodiments of the present disclosure. Detailed Implementation

[0030] The terminology used in this disclosure is for describing particular embodiments and is not intended to limit the scope of other embodiments. The singular form may include multiple forms unless explicitly indicated otherwise. All terms used herein, including technical and scientific terms, may have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure pertains. Among the terminology used in this disclosure, terms defined in general dictionaries may be interpreted as having the same or similar meaning as in the context of the relevant field, and should not be ideally or excessively interpreted as having a formal meaning unless explicitly defined in this disclosure. In some cases, even terms defined in this disclosure should not be construed as excluding embodiments of this disclosure.

[0031] In the various embodiments of this disclosure described below, hardware methods will be described as examples. However, since the various embodiments of this disclosure include techniques using both hardware and software, software-based methods are not excluded.

[0032] Subsequently, this disclosure relates to an apparatus and method for transmitting and receiving control information in a wireless communication system. Specifically, this disclosure explains techniques for transmitting and receiving control information in a wireless communication system based on a Channel Quality Indicator (CQI) and Modulation and Coding Scheme (MCS) table.

[0033] The terms used in the following description, such as those indicating signals, indicating channels, indicating control information, indicating network entities, and indicating components of devices, are for illustrative purposes. Therefore, this disclosure is not limited to the terms described, and other terms with the same technical meaning may be used.

[0034] In addition, this disclosure uses some communication standards (e.g., the 3rd Generation Partnership Project (3GPP)). rd The various embodiments described herein are based on terms used in the Generation Partnership Project (3GPP), and these terms are merely illustrative interpretations. The various embodiments of this disclosure can be readily modified and applied to other communication systems.

[0035] Figure 1 Wireless communication systems according to various embodiments of the present disclosure are shown. Figure 1 Base station 110, terminal 120, and terminal 130 are depicted as nodes using radio channels in a wireless communication system. Although Figure 1 Only one base station is depicted, but other base stations that are the same as or similar to base station 110 may be further included.

[0036] Base station 110 is network infrastructure used to provide radio access to terminals 120 and 130. Base station 110 has a coverage area defined based on signal transmission distance for a specific geographical region. Besides base station, base station 110 may be referred to as an access point (AP), eNodeB (eNB), fifth-generation node (5G node), radio point, transmission / reception point (TRP), or other terms with the same technical meaning.

[0037] Terminal 120 and terminal 130 are each devices used by a user and communicate with base station 110 via a radio channel. In some cases, at least one of terminal 120 and terminal 130 can operate without user intervention. That is, at least one of terminal 120 and terminal 130 is a device that performs machine-type communication (MTC) and can be carried by no user. Besides "terminal," each of terminal 120 and terminal 130 can be referred to as user equipment (UE), mobile station, subscriber station, remote terminal, wireless terminal, user equipment, or other terms with technical equivalents.

[0038] Base station 110, terminal 120, and terminal 130 can transmit and receive radio signals in millimeter-wave (mmWave) frequency bands (e.g., 28 GHz, 30 GHz, 38 GHz, 60 GHz). In doing so, base station 110, terminal 120, and terminal 130 can perform beamforming to improve channel gain. In this document, beamforming can include transmit beamforming and receive beamforming. That is, base station 110, terminal 120, and terminal 130 can apply directionality to the transmitted or received signals. For this purpose, base station 110, terminal 120, and terminal 130 can select serving beams 112, 113, 121, and 131 through a beam search or beam management process. After selecting serving beams 112, 113, 121, and 131, communication can be performed using resources quasi-co-located (QCL) carrying serving beams 112, 113, 121, and 131.

[0039] If the large-scale properties of the channel carrying symbols at the first antenna port can be inferred from the channel carrying symbols at the second antenna port, then the first antenna port and the second antenna port can be referred to as QCL. For example, large-scale properties may include at least one of delay spread, Doppler spread, Doppler offset, average gain, average delay, and spatial receiver parameters.

[0040] Figure 2The configuration of a base station in a wireless communication system according to various embodiments of the present disclosure is shown. Figure 2 The configuration in the document can be understood as the configuration of base station 110. Terms such as “part” or “device” used thereafter indicate a unit used to process at least one function or operation, and can be implemented using hardware, software, or a combination of hardware and software.

[0041] refer to Figure 2 The base station includes a wireless communication unit 210, a backhaul communication unit 220, a storage unit 230, and a control unit 240.

[0042] The wireless communication unit 210 can perform functions for transmitting and receiving signals via a radio channel. For example, the wireless communication unit 210 performs conversion functions between baseband signals and bit strings according to the system's physical layer standard. For example, in data transmission, the wireless communication unit 210 generates complex symbols by encoding and modulating the transmitted bit strings. Furthermore, in data reception, the wireless communication unit 210 recovers the received bit strings by demodulating and decoding the baseband signals.

[0043] Furthermore, the wireless communication unit 210 up-converts the baseband signal to a radio frequency (RF) band signal, transmits the signal via an antenna, and down-converts the RF band signal received via the antenna back to a baseband signal. For this purpose, the wireless communication unit 210 may include a transmit filter, a receive filter, an amplifier, a mixer, an oscillator, a digital-to-analog converter (DAC), an analog-to-digital converter (ADC), etc. Additionally, the wireless communication unit 210 may include multiple transmit and receive paths. Furthermore, the wireless communication unit 210 may include at least one antenna array comprising multiple antenna elements.

[0044] In terms of hardware, the wireless communication unit 210 may include digital units and analog units, and the analog units may include multiple sub-units depending on the operating power and operating frequency. The digital units may be implemented using at least one processor (e.g., a digital signal processor (DSP)).

[0045] As described above, the wireless communication unit 210 transmits and receives signals. Therefore, all or part of the wireless communication unit 210 may be referred to as a "transmitter," a "receiver," or a "transceiver." Furthermore, in the following text, transmission and reception on a radio channel are used to refer to the processes described above involving the wireless communication unit 210. In some embodiments, the wireless communication unit 210 may perform the function of transmitting and receiving signals using wired communication.

[0046] The backhaul communication unit 220 provides an interface for communicating with other nodes in the network. That is, the backhaul communication unit 220 converts bit strings sent from the base station to another node (e.g., another access node, another base station, an upper-layer node, or the core network) into physical signals, and converts physical signals received from another node into bit strings.

[0047] Storage unit 230 stores basic programs, application programs, and data such as setting information used to operate the base station. Storage unit 230 may include volatile memory, non-volatile memory, or a combination of volatile memory and non-volatile memory. Storage unit 230 provides the stored data according to requests from control unit 240.

[0048] Control unit 240 controls the overall operation of the base station. For example, control unit 240 transmits and receives signals via wireless communication unit 210 or backhaul communication unit 220. Furthermore, control unit 240 records data in storage unit 230 and reads data from storage unit 230. Control unit 240 can perform the functions of the protocol stack required by the communication standard. According to another embodiment, the protocol stack may be included in wireless communication unit 210. For this purpose, control unit 240 may include at least one processor.

[0049] According to various embodiments, control unit 240 can perform radio resource control (RRC) signaling with terminal 120. For example, control unit 240 can control base station to perform operations described according to various embodiments.

[0050] Figure 3 The configuration of a terminal in a wireless communication system according to various embodiments of the present disclosure is shown. Figure 3 The configuration shown can be understood as the configuration of terminal 120. Terms such as “part” or “device” used thereafter indicate a unit for processing at least one function or operation, and can be implemented using hardware, software, or a combination of hardware and software.

[0051] refer to Figure 3 The terminal 120 includes a communication unit 310, a storage unit 320, and a control unit 330.

[0052] Communication unit 310 can perform functions for transmitting and receiving signals via a radio channel. For example, communication unit 310 performs conversion between baseband signals and bit strings according to the system's physical layer standard. For instance, in data transmission, communication unit 310 generates complex symbols by encoding and modulating the transmitted bit strings. Furthermore, in data reception, communication unit 310 recovers the received bit strings by demodulating and decoding the baseband signals. Additionally, communication unit 310 up-converts baseband signals to RF band signals, transmits these signals via an antenna, and down-converts RF band signals received via the antenna back to baseband signals. For example, communication unit 310 may include transmit filters, receive filters, amplifiers, mixers, oscillators, DACs, ADCs, etc.

[0053] Furthermore, the communication unit 310 may include multiple transmit and receive paths. Additionally, the communication unit 310 may include at least one antenna array comprising multiple antenna elements. Given the hardware, the communication unit 310 may include digital and analog circuitry (e.g., an RF integrated circuit (RFIC)). In this document, the digital and analog circuitry may be implemented in a single package. Furthermore, the communication unit 310 may include multiple RF chains. Additionally, the communication unit 310 may perform beamforming.

[0054] Furthermore, the communication unit 310 may include different communication modules for processing signals in different frequency bands. Additionally, the communication unit 310 may include multiple communication modules for supporting different radio access technologies. For example, different radio access technologies may include Bluetooth Low Energy (BLE), Wi-Fi, Wi-Fi Gigabit (WiGig), and cellular networks (e.g., LTE). Furthermore, different frequency bands may include ultra-high frequency (SHF) bands (e.g., 2.5 GHz, 5 GHz) and millimeter wave (e.g., 60 GHz) bands.

[0055] Communication unit 310 transmits and receives signals as described above. Therefore, all or part of communication unit 310 may be referred to as a "transmitter," "receiver," or "transceiver." Furthermore, in the following explanation, transmission and reception on a radio channel are used to refer to the processes described above involving communication unit 310. In some embodiments, communication unit 310 may perform the function of transmitting and receiving signals using wired communication.

[0056] Storage unit 320 stores basic programs, application programs, and data such as settings information used to operate the terminal. Storage unit 320 may include volatile memory, non-volatile memory, or a combination of volatile memory and non-volatile memory. Storage unit 320 provides the stored data according to requests from control unit 330.

[0057] Control unit 330 controls the overall operation of the terminal. For example, control unit 330 sends and receives signals via communication unit 310. Furthermore, control unit 330 records data in storage unit 320 and reads data from storage unit 320. Control unit 330 can perform the functions of the protocol stack required by the communication standard. For this purpose, control unit 330 may include at least one processor or microprocessor, or may be part of a processor. Furthermore, communication unit 310 and a part of control unit 330 may be referred to as a communication processor (CP).

[0058] According to various embodiments, the control unit 330 can execute base station RRC signaling, determine the code rate based on the RRC configuration according to the RRC signaling, and use the code rate to determine the data size. For example, the control unit 330 can control the terminal to perform operations as explained according to various embodiments.

[0059] Figures 4A to 4C The configuration of a communication unit in a wireless communication system according to various embodiments of the present disclosure is shown. Figures 4A to 4C Depicting Figure 2 The wireless communication unit 210 or Figure 3 An example of a detailed configuration of the communication unit 310. More specifically, Figures 4A to 4C The components used to perform beamforming are depicted as follows: Figure 2 The wireless communication unit 210 or Figure 3 It is part of the communication unit 310.

[0060] refer to Figure 4A The wireless communication unit 210 or the communication unit 310 includes an encoder and modulator 402, a digital beamformer 404, multiple transmission paths 406-1 to 406-N, and an analog beamformer 408.

[0061] The encoder and modulator 402 perform channel coding. For channel coding, at least one of low-density parity-check (LDPC) codes, convolutional codes, and polar codes can be used. The encoder and modulator 402 generate modulation symbols by performing constellation mapping.

[0062] Digital beamformer 404 beamforms a digital signal (e.g., a modulation symbol). To do this, digital beamformer 404 multiplies the modulation symbol by beamforming weights. These beamforming weights are used to change the amplitude and phase of the signal and can be referred to as a 'precoding matrix' or 'precoder'. Digital beamformer 404 outputs the digitally beamformed modulation symbol to transmit paths 406-1 to 406-N. In doing so, depending on the multiple-input multiple-output (MIMO) transmission scheme, the modulation symbol can be multiplexed or the same modulation symbol can be provided to transmit paths 406-1 to 406-N.

[0063] Transmit paths 406-1 to 406-N convert the digital signals generated by digital beamforming into analog signals. For this purpose, each of transmit paths 406-1 to 406-N may include an inverse fast Fourier transform (IFFT) operator, a cyclic prefix (CP) adder, a DAC, and an up-converter. The CP adder is used for orthogonal frequency division multiplexing (OFDM) schemes and can be excluded if another physical layer scheme (e.g., filter bank multi-carrier (FBMC)) is applied. In other words, transmit paths 406-1 to 406-N provide independent signal processing for the multiple streams generated by digital beamforming. However, depending on the implementation, some components of transmit paths 406-1 to 406-N may be shared.

[0064] Analog beamformer 408 performs beamforming on an analog signal. To do this, digital beamformer 404 multiplies the analog signal by beamforming weights. Here, the beamforming weights are used to change the amplitude and phase of the signal. More specifically, depending on the connection structure between the transmission paths 406-1 to 406-N and the antenna, analog beamformer 408 can be configured as follows: Figure 4B or Figure 4C Configure as shown.

[0065] refer to Figure 4B The signal input to the analog beamformer 408 is phase-to-amplitude converted, amplified, and transmitted via the antenna. In doing so, the signal for each path is transmitted via a different set of antennas, i.e., an antenna array. The signal input in the first path is converted by phase-to-amplitude converters 412-1-1 to 412-1-M into a signal string with different or the same phase / amplitude, amplified by amplifiers 414-1-1 to 414-1-M, and then transmitted via the antenna.

[0066] refer to Figure 4C The signal input to the analog beamformer 408 is phase-to-amplitude converted, amplified, and transmitted via the antenna. In doing so, the signal for each path is transmitted via the same set of antennas, i.e., the same antenna array. The signal input in the first path is converted into a signal string with different or the same phase / amplitude by phase-to-amplitude converters 412-1-1 to 412-1-M, and amplified by amplifiers 414-1-1 to 414-1-M. For transmission via a single antenna array, the amplified signal is summed based on antenna elements by adders 416-1-1 to 416-1-M, and then transmitted via the antenna.

[0067] exist Figure 4B In this configuration, each transmission path uses an independent antenna array, and the transmission paths share [data / data]. Figure 4C A single antenna array is used. However, according to another embodiment, some transmission paths may use independent antenna arrays, while the remaining transmission paths may share a single antenna array. Furthermore, according to yet another embodiment, by applying a switchable structure between the transmission paths and the antenna array, a structure that adapts to circumstances can be used.

[0068] In LTE systems, a representative example of broadband wireless communication systems, the downlink employs an OFDM scheme, while the uplink uses a single-carrier (SC) frequency division multiple access (FDMA) scheme. As described above, this multiple access scheme distinguishes each user's data or control information through allocation and operation, ensuring that the time-frequency resources used to transmit each user's data or control information do not overlap, i.e., establishing orthogonality.

[0069] Figure 5 The basic structure of the frequency-time domain according to various embodiments of the present disclosure is shown. The frequency-time domain is a radio resource area used for transmitting data or control information in the downlink of an LTE system.

[0070] refer to Figure 5 The vertical axis indicates the time domain, and the horizontal axis indicates the frequency domain. The smallest unit of transmission in the time domain is an OFDM symbol, N. symb Yuan (N) symb OFDM symbol 502 constitutes a time slot 506, and two time slots constitute a subframe 505. The length of a time slot is 0.5 ms, and the length of a subframe is 1.0 ms. The smallest unit of transmission in the frequency domain is a subcarrier.

[0071] The basic resource unit in the time-frequency domain is the resource element (RE) 512, which can be indicated as an OFDM symbol index and a subcarrier index. A resource block (RB) 508 or a physical resource block (PRB) is defined as N in the time domain. symb Elementary continuous OFDM symbol 502 and N in the frequency domain RB SC 510 are continuous subcarriers. Therefore, an RB 508 includes N symb x N RB SC RE 512. Typically, the smallest unit of data transmission is RB, and the total system transmission bandwidth includes N. RB RB. Furthermore, the total transmission bandwidth of the entire system includes N. RB x N RB SC Subcarrier 504. In LTE systems, N is typically... symb =7 and N RB SC =12.

[0072] Control information is transmitted within the first N-ary OFDM symbol of a subframe. The control channel transmission period N is typically N = {1, 2, 3}. Therefore, for each subframe, the value N varies depending on the amount of control information to be transmitted in the current subframe. For example, control information may include indicators indicating how many OFDM symbols control information is transmitted over, uplink or downlink data scheduling information, hybrid automatic repeat request (HARQ) acknowledgment (ACK) / negative ACK (NACK) signals, etc.

[0073] If decoding fails during the initial transmission, the wireless communication system employs a HARQ scheme to retransmit the corresponding data at the physical layer. If the receiver fails to decode the data correctly, the HARQ scheme allows the receiver to send a notification of decoding failure (e.g., NACK) to the transmitter, enabling the transmitter to retransmit the corresponding data at the physical layer. The receiver improves data reception performance by combining the retransmitted data with the existing data that failed to decode. Alternatively, if the receiver decodes the data correctly, it can send a notification of successful decoding (e.g., ACK), allowing the transmitter to transmit new data.

[0074] One of the most important aspects of providing high-speed data services in wireless communication systems is the support for scalable bandwidth. In some embodiments, the system transmission band of an LTE system can have various bandwidths, such as 20 / 15 / 10 / 5 / 3 / 1.4MHz. Therefore, service providers can provide services by selecting a specific bandwidth from this range. Additionally, terminals (e.g., terminal 120) can be of various types, supporting a maximum bandwidth of 20MHz and a minimum bandwidth of only 1.4MHz.

[0075] In a wireless communication system, a base station (e.g., base station 110) notifies a terminal of uplink data or downlink data scheduling information via downlink control information (DCI). Uplink refers to the radio link used by the terminal to transmit data or control signals to the base station, and downlink refers to the radio link used by the base station to transmit data or control signals to the terminal. DCI is operated by defining various formats and applying a set DCI format based on uplink data scheduling information (UL permitted) or downlink data scheduling information (DL permitted), a compact DCI with a small control information size, spatial multiplexing using multiple antennas, and DCI for power control. For example, DCI format 1, as downlink data scheduling information (DL permitted), can be configured to include the following control information.

[0076] - Resource Allocation Type 0 / 1 Flag: The Resource Allocation Type 0 / 1 flag indicates whether the resource allocation scheme is Type 0 or Type 1. The Type 0 flag uses a bitmap scheme to allocate resources on a resource block group (RBG) basis. In LTE systems, the basic scheduling unit is an RB represented as time-domain and frequency-domain resources, and an RBG includes multiple RBs to form a Type 0 basic scheduling unit. The Type 1 flag allocates specific RBs within an RBG.

[0077] - Resource Block Allocation: The resource block allocation notification is the RB allocated for data transmission. The resource being represented is determined based on system bandwidth and resource allocation scheme.

[0078] -MCS: MCS indicates the modulation scheme used for data transmission and the size of the transport block to be transmitted.

[0079] -HARQ process ID: The process ID that HARQ notifies.

[0080] - New Data Indicator: The New Data Indicator notifies HARQ of the initial transmission or retransmission.

[0081] - Redundancy Version: The redundancy version notifies HARQ of the redundant version (RV).

[0082] - Transmit power control (TPC) commands for the physical uplink control channel (PUCCH): TPC commands for PUCCH notify the power control commands of PUCCH as the uplink control channel.

[0083] DCI performs channel coding, modulation, and transmission through the physical downlink control channel (PDCCH), which serves as the physical control channel for DL.

[0084] Typically, the DCI is channel-coded independently at each terminal and then configured and transmitted as an independent PDCCH. The PDCCH in the time domain is mapped and transmitted in the control channel transmission interval. The mapping position of the PDCCH in the frequency domain is determined by the identifier (ID) of each terminal and is distributed across the entire system transmission bandwidth.

[0085] Downlink data is transmitted via the physical downlink shared channel (PDSCH), which is the physical channel used for transmitting downlink data. The PDSCH is transmitted after the control channel transmission interval, and scheduling information such as specific mapping positions in the frequency domain or modulation schemes is communicated through DCI transmitted on the PDCCH.

[0086] The base station informs the terminal of the modulation scheme applied to the PDSCH to be transmitted and the data size (TBS) to be transmitted via the 5-bit MCS in the DCI control information. The TBS corresponds to the size of the data to be transmitted by the base station before the application of channel coding for error correction.

[0087] Typically, the modulation schemes supported in LTE include quadrature phase shift keying (QPSK), quadrature amplitude modulation (QAM), 64QAM, and 256QAM.

[0088] Figure 6 Modulation schemes that can be used in wireless communication systems according to various embodiments of the present disclosure are shown.

[0089] refer to Figure 6The modulation schemes supported in LTE systems correspond to QPSK, 16QAM, 64QAM, and 256QAM, each corresponding to a modulation order (Qm) of {2, 4, 6, 8}. That is, each QPSK modulation symbol can transmit 2 bits, each 16QAM modulation symbol can transmit 4 bits, each 64QAM modulation symbol can transmit 6 bits, and each 256QAM modulation symbol can transmit 8 bits. In 256QAM, the modulation order is 8 and 8 bits can be transmitted for each modulation symbol, thus achieving a 33% higher transmission efficiency than 64QAM. However, LTE systems do not consider supporting services with varying reliability. 5G systems, as advanced wireless communication systems, require a method for defining CQI and MCS tables suitable for supporting services with diverse reliability.

[0090] In a cellular system, a base station (e.g., base station 110) needs to transmit a reference signal to measure the channel state (DL). For example, in a 3GPP LTE-A system, a terminal (e.g., terminal 120) uses channel status information (CSI) – a reference signal (RS) transmitted by the base station – to measure the channel state between the base station and the terminal. The channel state needs to take into account several factors, including the amount of interference in the DL. The amount of interference in the DL includes thermal noise and interference signals caused by the antennas of neighboring base stations and can be used by the terminal to determine the channel conditions of the DL. For example, if a base station including a transmit antenna transmits an RS to a terminal including a receive antenna, the terminal determines the energy per symbol to interference density ratio (Es / Io) by determining the energy of each receivable symbol in the DL based on the RS received from the base station and by determining the amount of interference simultaneously received in the corresponding symbol's reception interval. The determined Es / Io is then communicated to the base station, allowing the base station to determine the data transmission rate used to transmit to the terminal in the DL.

[0091] Figure 7 An example of a CQI transmission of a terminal's channel state information based on the signal energy and interference level measured by the terminal, according to various embodiments of the present disclosure, is shown.

[0092] refer to Figure 7The terminal (e.g., terminal 120) performs channel estimation by measuring the DL RS, such as CSI-RS, and uses it to calculate Es (received signal energy) based on the radio channel, as shown by solid line 700. Additionally, the terminal uses separate resources or interference and noise used to measure the DL RS to calculate the intensity of interference and noise, as shown by dashed line 710. In LTE, the base station assumes the signal measured in the corresponding radio resource as interference and noise by using the CRS as the DL RS or by setting interference measurement resources for the terminal. Using the received signal energy and the interference and noise intensity obtained above, the terminal determines and informs the base station of the maximum receivable data transmission rate with a specific success rate at its calculated signal-to-interference-and-noise ratio. The base station, informed of the maximum data transmission rate that the terminal can support at the corresponding signal-to-interference-and-noise ratio, uses it to determine the actual data transmission rate of the DL signal to be transmitted to the terminal. Thus, the maximum receivable data transmission rate at the terminal with a specific success rate for the base station is referred to as CQI in the LTE standard. Typically, because radio channels vary over time, terminals periodically notify the base station of CQI, or the base station notifies the terminal upon request. One or more periodic and aperiodic methods can be used to execute the request from the base station to the terminal.

[0093] The modulation schemes supported in 5G systems include QPSK, 16QAM, 64QAM, and 256QAM. The maximum modulation order supported by the terminal can be achieved using different CQI tables and different MCS tables. Currently, the maximum modulation order in the CQI tables used in LTE systems is 64QAM, which maintains a uniform SNR gap between entries, effectively enabling the terminal to select the CQI that maximizes transmission efficiency and notify the base station. However, the maximum modulation order in the 256QAM table has wider SNR gaps between entries corresponding to low SNR than those between other entries. In this regard, various embodiments of this disclosure propose methods for generating new CQI tables instead of those where the maximum modulation order used in LTE is 256QAM. The methods for generating and applying CQI tables according to various embodiments of this disclosure are as follows.

[0094] - As with existing technologies, the CQI information content is kept at 4 bits to prevent signaling overhead.

[0095] -CQI index 0 remains outside the range.

[0096] -CQI Index 1 uses the same entries as CQI Index 1 in the table with a maximum modulation order of 64QAM. Therefore, the same coverage can be obtained between the two different tables.

[0097] The modulation scheme for CQI index 15 is 256QAM, and its code rate is 972 / 1024. Here, the code rate 972 / 1024 is approximately 0.95.

[0098] The entries for CQI indices 2 through 14 can be arranged with the maximum uniform SNR gap. One possible method for this is as follows: The terminal calculates the bit-interleaved coding and modulation (BICM) capacity for CQI index 1 and the BICM capacity for CQI index 15. Next, the terminal divides the gap between the two values ​​into 14 intervals. In doing so, the same RE number is assumed; because the CQI indexes of smaller indices correspond to relatively smaller information words, the gap between the CQI indices of smaller indices can be set to be relatively wider than the gaps of other CQI indices. In some embodiments, Table 1 shows the BICM capacity values ​​set for each CQI index (using the CQI table if the maximum modulation order is 256QAM). Here, the BICM capacity is a value rounded to the nearest one-hundredth.

[0099] - By referencing the BICM capacity curve, the optimal combination of modulation scheme and code rate for each CQI index is found. In some embodiments, the combination of modulation scheme and code rate is shown in Table 1.

[0100] Table 1

[0101]

[0102]

[0103] In some embodiments, if an entry value corresponding to two consecutive indices of an entry in the CQI table of Table 1 is used, the terminal performs one or more of the following operations.

[0104] - If the BLER with a code rate of 78 / 1024 and a modulation order of QPSK is lower than the target, the terminal will report CQI index #1 to the base station.

[0105] - If the BLER with a code rate of 78 / 1024 and a modulation order of QPSK is higher than the target, and the BLER with a code rate of 140 / 1024 and a modulation order of QPSK is lower than the target, the terminal reports CQI index #2 to the base station.

[0106] - If the BLER with a code rate of 140 / 1024 and a modulation order of QPSK is higher than the target, and the BLER with a code rate of 241 / 1024 and a modulation order of QPSK is lower than the target, the terminal reports CQI index #3 to the base station.

[0107] - If the BLER with a code rate of 241 / 1024 and a modulation order of QPSK is higher than the target, and the BLER with a code rate of 389 / 1024 and a modulation order of QPSK is lower than the target, the terminal reports CQI index #4 to the base station.

[0108] - If the BLER with a code rate of 389 / 1024 and a modulation order of QPSK is higher than the target, and the BLER with a code rate of 576 / 1024 and a modulation order of QPSK is lower than the target, the terminal reports CQI index #5 to the base station.

[0109] - If the BLER with a code rate of 576 / 1024 and a modulation order of QPSK is higher than the target, and the BLER with a code rate of 398 / 1024 and a modulation order of 16QAM is lower than the target, the terminal reports CQI index #6 to the base station.

[0110] - If the BLER with a code rate of 398 / 1024 and a modulation order of 16QAM is higher than the target, and the BLER with a code rate of 544 / 1024 and a modulation order of 16QAM is lower than the target, the terminal reports CQI index #7 to the base station.

[0111] - If the BLER with a code rate of 544 / 1024 and a modulation order of 16QAM is higher than the target, and the BLER with a code rate of 698 / 1024 and a modulation order of 16QAM is lower than the target, the terminal reports CQI index #8 to the base station.

[0112] - If the BLER with a code rate of 698 / 1024 and a modulation order of 16QAM is higher than the target, and the BLER with a code rate of 571 / 1024 and a modulation order of 64QAM is lower than the target, the terminal reports CQI index #9 to the base station.

[0113] - If the BLER with a code rate of 571 / 1024 and a modulation order of 64QAM is higher than the target, and the BLER with a code rate of 697 / 1024 and a modulation order of 64QAM is lower than the target, the terminal reports CQI index #10 to the base station.

[0114] - If the BLER with a code rate of 697 / 1024 and a modulation order of 64QAM is higher than the target, and the BLER with a code rate of 818 / 1024 and a modulation order of 64QAM is lower than the target, the terminal reports CQI index #11 to the base station.

[0115] - If the BLER with a code rate of 818 / 1024 and a modulation order of 64QAM is higher than the target, and the BLER with a code rate of 706 / 1024 and a modulation order of 256QAM is lower than the target, the terminal reports CQI index #12 to the base station.

[0116] - If the BLER with a code rate of 706 / 1024 and a modulation order of 256QAM is higher than the target, and the BLER with a code rate of 807 / 1024 and a modulation order of 256QAM is lower than the target, the terminal reports CQI index #13 to the base station.

[0117] - If the BLER with a code rate of 807 / 1024 and a modulation order of 256QAM is higher than the target, and the BLER with a code rate of 900 / 1024 and a modulation order of 256QAM is lower than the target, the terminal reports CQI index #14 to the base station.

[0118] - If the BLER with a code rate of 900 / 1024 and a modulation order of 256QAM is higher than the target, and the BLER with a code rate of 972 / 1024 and a modulation order of 256QAM is lower than the target, the terminal reports CQI index #15 to the base station.

[0119] The methods for generating and applying CQI tables according to other embodiments of this disclosure are as follows.

[0120] As in existing technologies, the CQI information content is kept at 4 bits to prevent signaling overhead.

[0121] -CQI index 0 remains outside the range.

[0122] -CQI Index 1 uses the same entries as CQI Index 1 in the table with a maximum modulation order of 64QAM. Therefore, the same coverage can be obtained between the two different tables.

[0123] The modulation scheme for CQI index 15 is 256QAM, and its code rate is 960 / 1024. Here, the code rate 960 / 1024 is approximately 0.9375.

[0124] The entries for CQI indices 2 through 14 can be arranged with the maximum uniform SNR gap. One possible method for this is as follows: The terminal calculates the BICM capacity for CQI index 1 and for CQI index 15. Next, the terminal divides the gap between the two values ​​into 14 intervals. In doing so, assuming the same RE number, the gap between the CQI indices of smaller indices can be set to be relatively wider than the gaps between other CQI indices because the CQI indices of smaller indices correspond to relatively smaller information words. In some embodiments, Table 2 shows the BICM capacity values ​​set for each CQI index (using the CQI table if the maximum modulation order is 256QAM). Here, the BICM capacity is rounded to the nearest one-hundredth of the value.

[0125] - By referencing the BICM capacity curve, the optimal combination of modulation scheme and code rate for each CQI index is found. In some embodiments, the combination of modulation scheme and code rate is shown in Table 2.

[0126] Table 2

[0127]

[0128] In some embodiments, if an entry value corresponding to two consecutive indices of an entry in the CQI table of Table 2 is used, the terminal performs one or more of the following operations.

[0129] - If the BLER with a code rate of 78 / 1024 and a modulation order of QPSK is lower than the target, the terminal will report CQI index #1 to the base station.

[0130] - If the BLER with a code rate of 78 / 1024 and a modulation order of QPSK is higher than the target, and the BLER with a code rate of 134 / 1024 and a modulation order of QPSK is lower than the target, the terminal reports CQI index #2 to the base station.

[0131] - If the BLER with a code rate of 134 / 1024 and a modulation order of QPSK is higher than the target, and the BLER with a code rate of 223 / 1024 and a modulation order of QPSK is lower than the target, the terminal reports CQI index #3 to the base station.

[0132] - If the BLER with a code rate of 223 / 1024 and a modulation order of QPSK is higher than the target, and the BLER with a code rate of 357 / 1024 and a modulation order of QPSK is lower than the target, the terminal reports CQI index #4 to the base station.

[0133] - If the BLER with a code rate of 357 / 1024 and a modulation order of QPSK is higher than the target, and the BLER with a code rate of 528 / 1024 and a modulation order of QPSK is lower than the target, the terminal reports CQI index #5 to the base station.

[0134] - If the BLER with a code rate of 528 / 1024 and a modulation order of QPSK is higher than the target, and the BLER with a code rate of 364 / 1024 and a modulation order of 16QAM is lower than the target, the terminal reports CQI index #6 to the base station.

[0135] - If the BLER with a code rate of 364 / 1024 and a modulation order of 16QAM is higher than the target, and the BLER with a code rate of 506 / 1024 and a modulation order of 16QAM is lower than the target, the terminal reports CQI index #7 to the base station.

[0136] - If the BLER with a code rate of 506 / 1024 and a modulation order of 16QAM is higher than the target, and the BLER with a code rate of 660 / 1024 and a modulation order of 16QAM is lower than the target, the terminal reports CQI index #8 to the base station.

[0137] - If the BLER with a code rate of 660 / 1024 and a modulation order of 16QAM is higher than the target, and the BLER with a code rate of 540 / 1024 and a modulation order of 64QAM is lower than the target, the terminal reports CQI index #9 to the base station.

[0138] - If the BLER with a code rate of 540 / 1024 and a modulation order of 64QAM is higher than the target, and the BLER with a code rate of 665 / 1024 and a modulation order of 64QAM is lower than the target, the terminal reports CQI index #10 to the base station.

[0139] - If the BLER with a code rate of 665 / 1024 and a modulation order of 64QAM is higher than the target, and the BLER with a code rate of 788 / 1024 and a modulation order of 64QAM is lower than the target, the terminal reports CQI index #11 to the base station.

[0140] - If the BLER with a code rate of 788 / 1024 and a modulation order of 64QAM is higher than the target, and the BLER with a code rate of 680 / 1024 and a modulation order of 256QAM is lower than the target, the terminal reports CQI index #12 to the base station.

[0141] - If the BLER with a code rate of 680 / 1024 and a modulation order of 256QAM is higher than the target, and the BLER with a code rate of 782 / 1024 and a modulation order of 256QAM is lower than the target, the terminal reports CQI index #13 to the base station.

[0142] - If the BLER with a code rate of 782 / 1024 and a modulation order of 256QAM is higher than the target, and the BLER with a code rate of 878 / 1024 and a modulation order of 256QAM is lower than the target, the terminal reports CQI index #14 to the base station.

[0143] - If the BLER with a code rate of 878 / 1024 and a modulation order of 256QAM is higher than the target, and the BLER with a code rate of 960 / 1024 and a modulation order of 256QAM is lower than the target, the terminal reports CQI index #15 to the base station.

[0144] Here, the BLER value can represent the probability of an error occurring after the decoding of a received transport block is complete. In some embodiments, the terminal can decode multiple transport blocks and then determine the BLER value through appropriate calculations; however, the BLER value can typically be determined from the received SNR. Therefore, the terminal can predict whether decoding was successful by simply measuring the received SNR without performing actual decoding and report the CQI index to the base station.

[0145] Furthermore, depending on the type of service supported in the 5G system, different levels of reliability may be required, and different CQI tables may be used depending on the required reliability. In some embodiments, the eMBB scenario operates for a BLER of 0.1 in 5G, but the URLLC scenario can operate for a BLER of 10^-5. Additionally, within either the eMBB or URLLC scenario, there may be scenarios that operate for two or more different BLERs or received SNRs. For example, URLLC scenario #1 can operate for a BLER of 10^-3, and URLLC scenario #2 can operate for a BLER of 10^-5.

[0146] The terminal can notify the base station of the CQI (Customer Quality Information) scheme, including the expected scenario to be served, the required reliability, or related information. Additionally, the base station can notify the terminal of the current scenario through RRC (Registered Rate Control) configuration. The CQI table used, or the entry value of each CQI index, can be changed according to the set scenario, required reliability, or related information.

[0147] Therefore, embodiments of this disclosure provide methods for generating and applying CQI tables to different scenarios. If two or more scenarios exist with different target BLERs (or received SNRs or their corresponding or related information) to support the same maximum modulation order, two or more different CQI tables corresponding to their target BLERs (or received SNRs or their corresponding or related information) can be used. In doing so, multiple entries in all entries of one or more CQI tables of the total CQI table can have a specified relationship with entries in other CQI tables that have the same CQI index. For example, in two or more CQI tables, multiple selected entries can have the same modulation order. In another example, in two or more CQI tables, multiple selected entries can have code rates that differ by a preset value. Here, the code rate is not the effective code rate, but a representative value of the code rate or nominal code rate. The nominal code rate can be expressed as a decimal between 0 and 1 in the code rate representation, but if the denominator is the square of 2, such as 1024, it can be expressed using the numerator value. For example, if the code rate is 0.5 and the denominator is 1024, it can be expressed as 512. This code rate is the code rate specified in the signaling, and due to additional overhead, it may not be precisely matched in actual decoding. For ease of description, the target BLER or the received SNR, or its corresponding or related information, may henceforth be referred to as the target BLER.

[0148] In other words, the terminal can use a specific CQI table to determine the modulation scheme and code rate, and then adjust and use the code rate by preset values ​​according to the scenario defined in its expected target BLER or RRC configuration.

[0149] Examples of CQI tables found in some embodiments are shown in Tables 3 through 7 (CQI tables are used if the maximum modulation order is 256QAM). The CQI tables in Tables 3 through 7 are CQI tables with the same maximum modulation order of 256QAM, but can be used in scenarios with different BLER targets. The terminal can determine which table entry values ​​are used via RRC configuration. The different CQI tables shown in Tables 3 through 7 have the same modulation order among entries with the same CQI index, and the code rate differs by 12, 24, 36, or 48 times for a 1024x code rate.

[0150] Table 3

[0151]

[0152]

[0153] Table 4

[0154]

[0155] Table 5

[0156]

[0157]

[0158] Table 6

[0159]

[0160] Table 7

[0161]

[0162] In the above embodiments, entries of CQI tables that have specific relationships with entries of other CQI tables are not represented separately, but can be represented by their relationship with entries of other CQI tables used as references. For example, in the above embodiments, multiple entries selected from two different tables are represented by the same modulation order and a code rate difference of 12, 24, 36, or 48.

[0163] In some embodiments, the found CQI tables may be shown in Tables 8 through 12 (if the maximum modulation order is 256QAM, then the CQI table is used). The CQI tables in Tables 8 through 12 are CQI tables with the same maximum modulation order of 256QAM, but can be used in scenarios with different target BLERs. The terminal can determine which table entry values ​​are used via RRC configuration. The different CQI tables shown in Tables 8 through 12 have the same modulation order among entries with the same CQI index, and the code rate differs by 12, 24, 36, or 48 times for a 1024x code rate.

[0164] Table 8

[0165]

[0166] Table 9

[0167]

[0168]

[0169] Table 10

[0170]

[0171] Table 11

[0172]

[0173]

[0174] Table 12

[0175]

[0176]

[0177] In the above embodiments, entries of CQI tables that have specific relationships with entries of other CQI tables are not represented separately, but can be represented by their relationship with entries of other CQI tables used as references. In some embodiments, multiple entries selected from two different tables can be represented by the same modulation order and a code rate difference of 12, 24, 36, or 48.

[0178] In some embodiments, the CQI table can be defined as shown in Tables 13 through 17 (the CQI table is used if the maximum modulation order is 64QAM). The CQI tables in Tables 13 through 17 are CQI tables with the same maximum modulation order of 64QAM, but can be used in scenarios with different BLER targets. The terminal can determine which table entry values ​​are used through RRC configuration. The terminal can determine which table entry values ​​are used through the terminal's CSI report. The different CQI tables shown in Tables 13 through 17 have the following relationship: entries with the same CQI index have the same modulation order, and the code rates differ by 12, 24, 36, or 48.

[0179] Table 13

[0180]

[0181]

[0182] Table 14

[0183]

[0184] Table 15

[0185]

[0186]

[0187] Table 16

[0188]

[0189] Table 17

[0190]

[0191] In the above embodiments, entries of CQI tables that have specific relationships with entries of other CQI tables are not represented separately, but can be represented by their relationship with entries of other CQI tables used as references. In the above embodiments, the modulation order is the same, and the code rate differs by 12, 24, 36, or 48.

[0192] As another embodiment of a method for generating CQI tables for application in different scenarios, multiple entries from all entries in one or more CQI tables within the entire CQI table can use multiple entries from other CQI tables by simply changing the CQI index. Alternatively, the modulation order can be maintained, and only the code rate setting can be changed. Other entries can be set to a modulation order and code rate with a specific frequency efficiency between the spectral efficiencies of two adjacent, different entries. As an example of defining a modulation order and code rate with a specific frequency efficiency, a method can exist for determining the modulation order and code rate with the desired intermediate SNR by referencing the BICM capacity.

[0193] The CQI tables generated in this way can be defined as shown in Tables 18 through 22 (if the maximum modulation order is 16QAM, then the CQI table is used). The CQI tables shown in Tables 18 through 22 are CQI tables available in scenarios with the same maximum modulation order of 16QAM but different BLER targets. The terminal can determine which table entry values ​​are applied via RRC configuration. The different CQI tables shown in Tables 18 through 22 have the same modulation order among entries with the same CQI index and the code rate differs by a multiple of 12. Furthermore, the CQI tables shown in Tables 18 through 22 use the eight CQI index entries from the CQI tables shown in Tables 3 through 7, or simply change the code rate by 12, 24, 36, or 48.

[0194] Table 18

[0195]

[0196] Table 19

[0197]

[0198]

[0199] Table 20

[0200]

[0201]

[0202] Table 21

[0203]

[0204] Table 22

[0205]

[0206]

[0207] In some embodiments, the CQI table can be defined as shown in Tables 23 through 27 (the CQI table is used if the maximum modulation order is 64QAM). The CQI tables in Tables 23 through 27 are available in scenarios with the same maximum modulation order of 16QAM but different BLER targets. The terminal can determine which table entry values ​​are applied via RRC configuration. The different CQI tables in Tables 23 through 27 have the same modulation order among entries with the same CQI index and the code rate differs by a multiple of 12. Furthermore, the CQI tables in Tables 23 through 27 use eight CQI index entries from the CQI tables in Tables 8 through 12, or simply change the code rate by 12, 24, 36, or 48.

[0208] Table 23

[0209]

[0210]

[0211] Table 24

[0212]

[0213] Table 25

[0214]

[0215]

[0216] Table 26

[0217]

[0218]

[0219] Table 27

[0220]

[0221] Here, some entries with high CQI indexes in the newly generated CQI table can be replaced with reserved fields.

[0222] Alternatively, some entries in the new CQI table can be assigned to higher CQI indices using specific CQI indices, and the remaining lower CQI indices can be reconfigured for modulation order and code rate with lower spectral efficiency.

[0223] The CQI table generated in this way can be defined as shown in Table 28. This is a CQI table using entries corresponding to the nine CQI indices in the existing CQI table. The other six entries can be reserved or populated with entries to support lower spectral efficiency.

[0224] Table 28

[0225]

[0226] In various embodiments of this disclosure, modulation schemes other than QPSK, 16QAM, 64QAM, and 256QAM can be applied to the CQI table. For example, pi / 2-BPSK modulation schemes or 1024QAM can be further included.

[0227] MCS can be designed and used similarly to CQI. It's worth noting that an MCS, which uses more signaling bits, may have more table entries than a CQI. Furthermore, all or part of the modulation order and code rate defined in the CQI table can be reused in the MCS table.

[0228] The TBS can be calculated using the code rate known in the MCS. In some embodiments, the TBS can be determined by the number of allocated REs, the number of layers used, the transmission order, the code rate, etc. The transmission order and code rate of various factors determining the TBS can be obtained from the MCS of the signaling information. In some embodiments, the modulation order obtained through the MCS can be used as is, and the code rate obtained through the MCS can be additionally adjusted according to the RRC configuration information. In some embodiments, if only an MCS table is defined for services with high target BLER, and this MCS table is configured to support services with the same maximum modulation order but low target BLER via RRS signaling, the transceiver can obtain the modulation order and code rate from the defined MCS table and only adjust and use the code rate. Various methods can be used to adjust the code rate. For example, a method of subtracting a preset constant value from the code rate can be used. When doing so, the constant value subtracted from the code rate can be the same value for each CQI index, or a value that varies according to the modulation order. In some embodiments, the code rate can be defined based on Equation 1.

[0229] Equation 1

[0230] R = f(R', P)

[0231] Here, R can represent the bitrate applied to TBS calculation, R' can represent the bitrate obtained from an existing table, and P can represent service scenario or service mode related parameters obtained from RRC configuration.

[0232] In other embodiments, the bit rate can be defined as Equation 2.

[0233] Equation 2

[0234] R = f(R', P) = R' - a(P)

[0235] Here, R can represent the code rate applied to TBS calculation, R' can represent the code rate obtained from an existing table, P can represent service scenario or service mode related parameters obtained from RRC configuration, and a(P) can represent a constant value determined based on the service scenario or mode related parameter P. That is, for a predefined constant a, Equation 1 can be expressed as R = R' - a, and the constant a can use the same value regardless of the service scenario or mode, but optimized performance can be achieved by using different values, such as 12 / 1024, 24 / 1024, 36 / 1024, or 48 / 1024. Here, the service scenario or mode can be defined on various bases and can be changed according to various system requirements, such as user category, target BLER, or modulation order. Furthermore, the service scenario or mode can be determined by combining multiple bases.

[0236] Equation 1 only describes subtracting a specific constant value from the bitrate, but it can be implemented in various ways. For example, according to various embodiments of this disclosure, the method can be implemented by setting a reference denominator value used to indicate the bitrate to 1024, calling the bitrate*1024 value from each CQEI or MCS table, and subtracting a specific integer constant (as in the CQI or MCS table) from that value. As an example of the method described in Equation 1, if a constant such as 12, 24, 36, or 46 is subtracted from the value R*1024 corresponding to the appropriate bitrate R, the same effect as subtracting 12 / 1024, 24 / 1024, 36 / 1024, or 48 / 1024 in Equation 1 can be achieved. Thus, applications based on the bitrate expressed in Equation 1 have various methods for obtaining the same effect. In some embodiments, various embodiments of this disclosure can be implemented by setting an appropriate value corresponding to the bitrate and then readjusting the appropriate value corresponding to the bitrate using its appropriate constant value.

[0237] In some embodiments, various embodiments of the present disclosure based on Equation 1 can be implemented by designing multiple CQI or MCS tables as mentioned above. For example, in a wireless communication system using multiple CQI or MCS tables, if the code rates or their corresponding values ​​corresponding to the same index in two CQI or MCS tables are set to exhibit a difference of a preset value, the same effect as the various embodiments of the present disclosure based on Equation 1 can be achieved.

[0238] Figure 8A flowchart of a terminal for calculating TBS using CQI and MCS tables according to various embodiments of the present disclosure is shown. Figure 8 The operation method of terminal 120 is shown.

[0239] refer to Figure 8 The base station (e.g., base station 110) signals the RRC to the terminal by considering the services to be provided to the terminal. In step 801, the terminal performs RRC configuration. In step 803, the terminal obtains a code rate and transmission order as a reference. In step 805, if the services defined in the RRC configuration differ from the reference services, the terminal adjusts the code rate. Specific methods for obtaining the code rate and transmission order, and methods for adjusting the code rate, are consistent with various embodiments of this disclosure. In step 807, the terminal uses the adjusted code rate to calculate the TBS.

[0240] Figure 9 Another flowchart is shown for a terminal for calculating TBS using CQI and MCS tables according to various embodiments of the present disclosure. Figure 9 The operation method of terminal 120 is shown.

[0241] refer to Figure 9 The base station (e.g., base station 110) signals the RRC to the terminal by considering the services to be provided to the terminal. In step 901, the terminal performs RRC configuration. In step 903, the terminal obtains a code rate and transmission order as a reference. In step 905, if the service defined in the RRC configuration differs from the reference service, the terminal adjusts the code rate. Specific methods for obtaining the code rate and transmission order, and methods for adjusting the code rate, are consistent with various embodiments of this disclosure. In step 907, the terminal uses the adjusted code rate to provide feedback on the channel state.

[0242] In some embodiments, base station 110 and terminal 120 may communicate using at least one of wireless communication and wired communication.

[0243] The methods described in the claims or this disclosure can be implemented in software, hardware, or a combination of hardware and software.

[0244] For software, a computer-readable storage medium may be provided to store one or more programs (software modules). The one or more programs stored in the computer-readable storage medium may be configured to be executed by one or more processors of an electronic device. The one or more programs may include instructions for controlling the electronic device to perform methods according to embodiments described in the claims or this disclosure.

[0245] Such programs (software modules, software) can be stored in random access memory, including non-volatile memory such as flash memory, read-only memory (ROM), electrically erasable programmable ROM (EEPROM), disk storage devices, optical disc (CD)-ROMs, digital versatile discs (DVDs) or other optical storage devices, and magnetic tape. Alternatively, the program can be stored in some or all of the memory combined with those recording media. Multiple memories may be included.

[0246] The program can be stored in a connectable storage device that can be accessed via a communication network such as the Internet, intranet, local area network (LAN), wide area network (WLAN), or storage area network (SAN), or a combination of these networks. Such a storage device can access the device executing embodiments of this disclosure via an external port. Furthermore, a separate storage device on the communication network can access the device executing embodiments of this disclosure.

[0247] In certain embodiments of this disclosure, elements included in this disclosure are expressed in singular or plural form. However, for ease of interpretation, the singular or plural expression may be appropriately chosen depending on the circumstances presented. This disclosure is not limited to a single element or multiple elements; an element expressed in plural form may be configured as a single element, and an element expressed in singular form may be configured as multiple elements.

[0248] Furthermore, while specific embodiments have been described in the explanation of this disclosure, it should be noted that various changes can be made therein without departing from the scope of this disclosure. Therefore, the scope of this disclosure is not limited to or restricted by the described embodiments, and is defined not only by the scope of the appended claims, but also by their equivalents.

Claims

1. A method performed by a user equipment (UE) in a wireless communication system, the method comprising: Configuration information for indicating one of multiple modulation and coding scheme (MCS) tables is received from the base station (BS) via Radio Resource Control (RRC) signaling. The plurality of MCS tables mentioned above include: The first MCS table includes multiple MCS indexes; and A second MCS table including multiple MCS indexes, The method further includes: If the configuration information indicates a second MCS table, the MCS index is identified from the second MCS table; and Receive data using the identified MCS index. The first MCS index of the first MCS table indicating the first modulation scheme and the first code rate is lower than the second MCS index of the second MCS table indicating the first modulation scheme and the first code rate. The first MCS table and the second MCS table contain the same maximum modulation order.

2. The method according to claim 1, The plurality of MCS indexes mentioned above include: The first MCS index is represented as (QPSK, 120 / 1024), the third MCS index is represented as (QPSK, 193 / 1024), the fourth MCS index is represented as (QPSK, 308 / 1024), the fifth MCS index is represented as (QPSK, 449 / 1024), the sixth MCS index is represented as (QPSK, 602 / 1024), the seventh MCS index is represented as (16-QAM, 378 / 1024), the eighth MCS index is represented as (16-QAM, 490 / 1024), and the ninth MCS index is represented as (16-QAM, 616 / 1024).

3. The method according to claim 1, further comprising: In the case where one of the multiple MCS tables is the second MCS table, the transport block received from the BS has an error probability not exceeding the second block error rate (BLER).

4. The method according to claim 1, The second MCS table is configured to include lower spectral efficiency than the first MCS table in the same index.

5. The method according to claim 1, The first modulation scheme and the first code rate are included in the first CQI table and the second CQI table. The first CQI table is associated with the first BLER 0.1, and The second CQI table is associated with the second BLER 0.00001.

6. A user equipment (UE) in a wireless communication system, comprising: At least one transceiver; and At least one processor operably connected to at least one transceiver; The at least one processor is configured to: Configuration information for indicating one of multiple modulation and coding scheme (MCS) tables is received from the base station (BS) via Radio Resource Control (RRC) signaling. The plurality of MCS tables mentioned therein include: The first MCS table includes multiple MCS indexes; and A second MCS table including multiple MCS indexes, The at least one processor is further configured to: If the configuration information indicates a second MCS table, the MCS index is identified from the second MCS table; and Receive data using the identified MCS index. The first MCS index of the first MCS table indicating the first modulation scheme and the first code rate is lower than the second MCS index of the second MCS table indicating the first modulation scheme and the first code rate. The first MCS table and the second MCS table contain the same maximum modulation order.

7. The UE according to claim 6, The plurality of MCS indexes mentioned above include: The first MCS index is represented as (QPSK, 120 / 1024), the third MCS index is represented as (QPSK, 193 / 1024), the fourth MCS index is represented as (QPSK, 308 / 1024), the fifth MCS index is represented as (QPSK, 449 / 1024), the sixth MCS index is represented as (QPSK, 602 / 1024), the seventh MCS index is represented as (16-QAM, 378 / 1024), the eighth MCS index is represented as (16-QAM, 490 / 1024), and the ninth MCS index is represented as (16-QAM, 616 / 1024).

8. The UE according to claim 6, wherein, The at least one processor is further configured to: In the case where one of the multiple MCS tables is the second MCS table, the transport block received from the BS has an error probability not exceeding the second block error rate (BLER).

9. The UE according to claim 6, The second MCS table is configured to include lower spectral efficiency than the first MCS table in the same index.

10. The UE according to claim 6, The first modulation scheme and the first code rate are included in the first CQI table and the second CQI table. The first CQI table is associated with the first BLER 0.1, and The second CQI table is associated with the second BLER 0.00001.

11. A method performed by a base station (BS) in a wireless communication system, the method comprising: Configuration information indicating one of multiple modulation and coding scheme (MCS) tables is sent to the user equipment (UE) via Radio Resource Control (RRC) signaling. The plurality of MCS tables mentioned therein include: The first MCS table includes multiple MCS indexes; and A second MCS table including multiple MCS indexes, The method further includes using the configuration information to send data. The first MCS index of the first MCS table indicating the first modulation scheme and the first code rate is lower than the second MCS index of the second MCS table indicating the first modulation scheme and the first code rate. The first MCS table and the second MCS table contain the same maximum modulation order.

12. The method according to claim 11, The plurality of MCS indexes mentioned above include: The first MCS index is represented as (QPSK, 120 / 1024), the third MCS index is represented as (QPSK, 193 / 1024), the fourth MCS index is represented as (QPSK, 308 / 1024), the fifth MCS index is represented as (QPSK, 449 / 1024), the sixth MCS index is represented as (QPSK, 602 / 1024), the seventh MCS index is represented as (16-QAM, 378 / 1024), the eighth MCS index is represented as (16-QAM, 490 / 1024), and the ninth MCS index is represented as (16-QAM, 616 / 1024).

13. The method of claim 11, further comprising: If one of the multiple MCS tables is the second MCS table, transmit blocks to the UE with an error probability not exceeding the second block error rate (BLER).

14. The method according to claim 11, The second MCS table is configured to include lower spectral efficiency than the first MCS table in the same index.

15. The method according to claim 11, The first modulation scheme and the first code rate are included in the first CQI table and the second CQI table. The first CQI table is associated with the first BLER 0.1, and The second CQI table is associated with the second BLER 0.00001.

16. A base station (BS) in a wireless communication system, comprising: At least one transceiver; and At least one processor is operatively connected to at least one transceiver; The at least one processor is configured to: Configuration information indicating one of multiple modulation and coding scheme (MCS) tables is sent to the user equipment (UE) via Radio Resource Control (RRC) signaling. The plurality of MCS tables mentioned therein include: The first MCS table includes multiple MCS indexes; and A second MCS table including multiple MCS indexes, The at least one processor is also configured to use the configuration information to send data. The first MCS index of the first MCS table indicating the first modulation scheme and the first code rate is lower than the second MCS index of the second MCS table indicating the first modulation scheme and the first code rate. The first MCS table and the second MCS table contain the same maximum modulation order.

17. The BS according to claim 16, The plurality of MCS indexes mentioned above include: The first MCS index is represented as (QPSK, 120 / 1024), the third MCS index is represented as (QPSK, 193 / 1024), the fourth MCS index is represented as (QPSK, 308 / 1024), the fifth MCS index is represented as (QPSK, 449 / 1024), the sixth MCS index is represented as (QPSK, 602 / 1024), the seventh MCS index is represented as (16-QAM, 378 / 1024), the eighth MCS index is represented as (16-QAM, 490 / 1024), and the ninth MCS index is represented as (16-QAM, 616 / 1024).

18. The BS of claim 16, wherein the at least one processor is further configured to: If one of the multiple MCS tables is the second MCS table, transmit blocks to the UE with an error probability not exceeding the second block error rate (BLER).

19. The BS according to claim 16, The second MCS table is configured to include lower spectral efficiency than the first MCS table in the same index.

20. The BS according to claim 16, The first modulation scheme and the first code rate are included in the first CQI table and the second CQI table. The first CQI table is associated with the first BLER 0.1, and The second CQI table is associated with the second BLER 0.00001.

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