Method and apparatus for link adaptation in wireless communication system

Abstract

A link adaptation method according to an embodiment of the present disclosure is a method performed by a base station in a wireless communication system and comprises the operations of: transmitting first URLLC data to a user equipment (UE) on the basis of a first time resource and a first frequency resource; transmitting a padding signal to the UE on the basis of a second time resource and the first frequency resource; receiving a first hybrid automatic repeat request (HARQ) signal for the padding signal from the UE; generating a block error rate (BLER) value; generating a correction constant for a signal-to-interference-plus-noise ratio (SINR) on the basis of the BLER value; correcting an outer loop rate control (OLRC) offset on the basis of the first HARQ signal; correcting the SINR on the basis of the corrected OLRC offset and the correction constant; and on the basis of a modulation and coding scheme (MCS) determined on the basis of the corrected SINR, transmitting second URLLC data to the UE on the basis of a third time resource and the first frequency resource.

Description

Method and device for link adaptation in wireless communication systems

[0001] The present disclosure relates to a method and device for link adaptation in a wireless communication system, and more particularly, to a method and device for controlling a transmission method based on a channel condition of a wireless environment.

[0002] A channel is a value that represents the signal change characteristics between a base station and a terminal in a wireless communication environment. It can be determined by various factors such as terminal movement, obstacles, multipath, and sudden occurrence of interference signals. Since wireless channels change over time, it is difficult to use a fixed transmission technique to adjust service quality. This can be addressed through a technique called link adaptation. During the link adaptation process, the base station first periodically receives and processes a channel quality indicator (CQI) containing quantized reception SINR (signal-to-interference-plus-noise ratio) information from the terminal to determine the channel condition. Afterwards, the base station can select an MCS that satisfies the target communication service quality based on the determined channel condition and transmit data using it.

[0003] In this regard, as one of the link adaptation techniques, inner loop rate control (ILRC) technology can determine MCS using only periodically transmitted CQI, but this does not reflect channel condition changes between transmitted CQI periods. As a method to complement ILRC, outer loop rate control (OLRC) method can utilize HARQ (hybrid automatic repeat request) response information that is fed back to the base station every TTI along with CQI from the terminal.

[0004] The HARQ signal indicates whether there is an error in the transport block transmitted from the base station. If the transmission is received without an error, the terminal can feed back an ACK signal to the base station, and if there is an error, the terminal can feed back a NACK signal. The terminal can receive data from the base station in units of transport blocks modified according to the MCS, and can perform a cyclic redundancy check (CRC) on each received block to determine whether there is an error and transmit a HARQ signal to the base station. A typical outer-loop transmission rate control method can utilize the HARQ feedback to correct the OLRC offset value and modify the SINR estimated from the CQI. Depending on the status (ACK / NACK) of the HARQ feedback, the OLRC offset can be increased or decreased by a specific value, and the OLRC offset value can be used to update the estimated SINR. Ultimately, the updated result of the estimated SINR changes depending on the status of the HARQ feedback, and the base station can determine the MCS accordingly and transmit data adaptively to the channel conditions.

[0005] For URLLC (Ultra Reliable Low Latency Communication) data, the target error rate is extremely low. Therefore, even if the channel environment changes rapidly, it is necessary to quickly adapt and manage the data error rate, and technology for this purpose is needed.

[0006] The present disclosure aims to provide a method and device for controlling link adaptation to quickly converge to a target error rate despite rapid changes in channel conditions during data transmission and reception.

[0007] According to one embodiment of the present disclosure, a method is performed by a base station in a wireless communication system, the method including: transmitting first URLLC data to a user equipment (UE) based on a first time resource and a first frequency resource; transmitting a padding signal to the UE based on a second time resource and a first frequency resource; receiving a first hybrid automatic repeat request (HARQ) signal for the padding signal from the UE; generating a block error rate (BLER) value; generating a correction constant for a signal-to-interference-plus-noise ratio (SINR) based on the BLER value; correcting an outer loop rate control (OLRC) offset based on the first HARQ signal; correcting the SINR based on the corrected OLRC offset and the correction constant; and transmitting second URLLC data to the UE based on a modulation and coding scheme (MCS) determined based on the corrected SINR based on a third time resource and a first frequency resource.

[0008] In addition, according to one embodiment of the present disclosure, a device is a base station of a wireless communication system, including a transceiver and a processor connected to the transceiver, wherein the processor is configured to transmit first URLLC data to a user equipment (UE) based on a first time resource and a first frequency resource, transmit a padding signal to the UE based on a second time resource and a first frequency resource, receive a first hybrid automatic repeat request (HARQ) signal for the padding signal from the UE, generate a block error rate (BLER) value, generate a correction constant for a signal-to-interference-plus-noise ratio (SINR) based on the BLER value, correct an outer loop rate control (OLRC) offset based on the first HARQ signal, correct a signal-to-interference-plus-noise ratio (SINR) based on the corrected OLRC offset and correction constant, and transmit second URLLC data to the UE based on a modulation and coding scheme (MCS) determined based on the corrected SINR. It is configured to perform an operation of transmitting based on the first frequency resource.

[0009] A method and device according to one embodiment of the present disclosure can transmit data by selecting an optimal modulation and coding scheme (MCS) to support ultra-reliable and low latency communications (URLLC) in a wireless communication system (e.g., a 5G NR system).

[0010] That is, the method and device according to one embodiment of the present disclosure can quickly determine a channel state and transmit URLLC data by determining an SINR update and MCS based on the determined channel state.

[0011] In addition, the method and device according to one embodiment of the present disclosure can control the data transmission environment to quickly converge to a target error rate even if the channel condition changes rapidly.

[0012] The effects that can be obtained from the present disclosure are not limited to the effects mentioned above, and other effects that are not mentioned can be clearly understood by a person having ordinary skill in the art to which the present disclosure belongs from the description below.

[0013] The features and advantages of one embodiment of the present disclosure will become more apparent from the following description taken in conjunction with the accompanying drawings.

[0014] Figure 1 illustrates traffic of URLLC data according to one embodiment of the present disclosure.

[0015] FIG. 2 illustrates traffic of URLLC data and traffic of padding signals according to one embodiment of the present disclosure.

[0016] Figure 3 illustrates a method according to one embodiment of the present disclosure.

[0017] FIG. 4 illustrates a method performed by a UE according to one embodiment of the present disclosure.

[0018] FIG. 5 illustrates a method performed by a base station according to one embodiment of the present disclosure.

[0019] FIG. 6 illustrates a method performed by a base station according to one embodiment of the present disclosure.

[0020] FIG. 7 is a graph showing the difference between a generated BLER and a target BLER according to one embodiment of the present disclosure.

[0021] FIG. 8 illustrates a method for generating a correction constant for SINR according to one embodiment of the present disclosure.

[0022] FIG. 9 illustrates a method for generating a correction constant for SINR according to one embodiment of the present disclosure.

[0023] FIG. 10 is a graph showing changes in BLER values ​​according to one embodiment of the present disclosure.

[0024] FIG. 11 is a graph showing changes in BLER values ​​according to one embodiment of the present disclosure.

[0025] FIG. 12 is a graph showing changes in BLER values ​​according to one embodiment of the present disclosure.

[0026] FIG. 13 is a graph showing changes in BLER values ​​according to one embodiment of the present disclosure.

[0027] FIG. 14 is a graph showing changes in BLER values ​​according to one embodiment of the present disclosure.

[0028] FIG. 15 is a graph showing changes in BLER values ​​according to one embodiment of the present disclosure.

[0029] FIG. 16 is a graph showing changes in BLER values ​​according to one embodiment of the present disclosure.

[0030] FIG. 17 is a graph showing changes in BLER values ​​according to one embodiment of the present disclosure.

[0031] FIG. 18 illustrates components of a UE according to one embodiment of the present disclosure.

[0032] FIG. 19 illustrates components of a base station according to one embodiment of the present disclosure.

[0033] Embodiments of the present disclosure may address the problems and / or disadvantages described above and provide the advantages described below. One aspect of the present disclosure may provide a terminal and a communication method thereof in a wireless communication system.

[0034] The terms used in this disclosure are used only to describe specific embodiments and may not be intended to limit the scope of other embodiments. The singular expression 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 those of ordinary skill in the art described in this disclosure. Terms defined in general dictionaries among the terms used in this disclosure may be interpreted as having the same or similar meaning in the context of the relevant technology, and shall not be interpreted in an idealized or overly formal sense unless explicitly defined in this disclosure. In some cases, even if a term is defined in this disclosure, it cannot be interpreted to exclude embodiments of the present disclosure.

[0035] The various embodiments of the present disclosure described below illustrate hardware-based approaches. However, since the various embodiments of the present disclosure encompass techniques utilizing both hardware and software, the various embodiments of the present disclosure do not exclude software-based approaches.

[0036] Additionally, although various embodiments of the present disclosure describe various embodiments using terminology used in certain communication standards (e.g., 3rd generation partnership project (3GPP)), this is merely an example for illustrative purposes. Various embodiments of the present disclosure can be easily modified and applied to other communication systems.

[0037] Hereinafter, various embodiments of the present disclosure will be described.

[0038] Figure 1 illustrates traffic of URLLC data according to one embodiment of the present disclosure.

[0039] URLLC (Ultra Reliable Low Latency Communication) is one of the core services provided by 5G NR systems, along with enhanced mobile broadband (eMBB) and massive machine type communication (mMTC). URLLC can be used for services such as telemedicine, remote control of robots, autonomous vehicles, and real-time interactive games. Since URLLC requires very low latency and high reliability, the target BLER (Block Error Rate) value is typically 10 -3 10 inland -6 It could be the extent of it.

[0040] Referring to Figure 1, in a URLLC environment, a base station can intermittently transmit small-sized data (approximately 100 bytes). Therefore, for empty intervals during which no data is transmitted, the base station cannot receive HARQ feedback from the terminal and cannot perform outer-loop rate control (OLRC) operations. In situations where the channel environment changes rapidly, the previously estimated signal-to-interference-plus-noise ratio (SINR) may not accurately reflect the current channel conditions. Therefore, transmitting data based on the previously estimated SINR may degrade reliability in a URLLC environment that requires high reliability.

[0041] In addition, the conventional outer loop link adaptation (OLRC) method takes a lot of time to correct the estimated SINR to the actual channel environment when the channel quality indicator (CQI) received by the base station from the terminal is inaccurate or when the channel environment changes rapidly.

[0042] A method and device according to an embodiment of the present disclosure propose a method or device that maintains high reliability in a URLLC environment and shortens the time required to reach a target error rate by correcting SINR to suit an actual channel environment.

[0043] FIG. 2 illustrates traffic of URLLC data and traffic of padding signals according to one embodiment of the present disclosure.

[0044] Referring to FIG. 2, URLLC data traffic may exist intermittently over time, and padding signals may exist between URLLC data traffic.

[0045] That is, the base station can periodically transmit a padding signal to the user equipment (UE) in the interval between URLLC data that is transmitted intermittently. The user equipment can receive the padding signal from the base station, check the padding signal for an error, and transmit a HARQ signal to the base station. The base station can update the ORLC offset based on the received HARQ signal and correct the SINR based on the updated ORLC offset. Then, the base station can determine the MCS based on the corrected SINR and transmit the URLLC data to the user equipment. That is, it can be understood that the base station transmits the padding signal in order to receive the HARQ signal for the padding signal from the user equipment. Since the padding signal does not contain meaningful information, it can be referred to as dummy data or dummy signal, and can represent a transmission block that is entirely filled with zero padding bits.

[0046] Padding signals can be transmitted at regular intervals between URLLC data traffic segments. The base station's transmission frequency of the padding signal can be set based on a preset value. Furthermore, the transmission frequency of the padding signal can be adaptively changed based on channel conditions. For example, the transmission frequency of the padding signal can be changed based on the rate of change in the channel conditions or the difference between the current error rate and the target error rate. If the channel conditions change rapidly or the difference between the current error rate and the target error rate is greater than a certain threshold, the transmission frequency of the padding signal can be set shorter. In other words, the base station can transmit the padding signal to the user terminal more frequently.

[0047] The base station may prioritize the transmission of URLLC data when the transmission timings of URLLC data and padding signals overlap. The base station may receive a HARQ signal for URLLC data from the terminal to correct the OLRC offset. When the base station corrects the OLRC offset and SINR based on the HARQ signal for the padding signal or the HARQ signal for URLLC data, the target BLER (Block Error Rate) value may be set to the same value.

[0048] FIG. 3 illustrates a method for link adaptation according to one embodiment of the present disclosure.

[0049] In operation 302, the UE (200) measures a signal-to-interference-plus-noise ratio (SINR), and in operation 304, the UE (200) can transmit a channel quality indicator (CQI) including information about the measured SINR to the base station (100).

[0050] In operation 306, the base station (100) can estimate SINR based on the CQI received from the UE (200) and determine a modulation and coding scheme (MCS) based on the estimated SINR.

[0051] In operations 308 and 310, the base station (100) can configure a data transmission block based on the determined MCS and transmit URLLC data or a padding signal to the UE (200) through the configured data transmission block.

[0052] In operation 312, the UE (200) performs a block error check (or cyclic redundancy check) (CRC) on the received data transmission block, and in operation 314, the UE (200) can transmit a HARQ signal (ACK signal or NACK signal) to the base station (100) based on whether there is an error in the received transmission block.

[0053] In operation 316, the base station (100) can generate a BLER based on the HARQ signal received from the UE (200). At this time, the base station (100) can generate a BLER value by considering the last received HARQ signal and the HARQ signal received before that. For example, when the base station (100) receives multiple HARQ signals as it repeats data (or signal) transmission, the base station (100) can generate a BLER value based on the multiple HARQ signals.

[0054] When the base station (100) generates a BLER value based on multiple HARQ signals, the base station (100) may generate a BLER value by considering multiple HARQ signals generated from the first transmission time to any arbitrary transmission time. In this case, the first transmission time may indicate the time when the base station (100) first transmits after receiving a CQI report from the UE (200).

[0055] In addition, when the base station (100) generates a BLER value based on a plurality of HARQ signals, the base station (100) may generate a BLER value by considering a plurality of HARQ signals within a specific range before any transmission time. At this time, the specific range may be defined based on the number of times and / or time of initial transmission for a transport block. In addition, the specific range may be defined by the base station generating and storing an index for a NACK signal, adding 1 to the index value for the NACK signal whenever it receives a HARQ signal for URLLC data, and generating a BLER value when the index value for the NACK signal exceeds a preset parameter value. That is, the specific range may be determined by comparing the index value for the NACK signal with the preset parameter value.

[0056] As an example, when the base station (100) generates a BLER value based on the number of initial transmissions for a transport block, the base station (100) may generate the BLER value based on HARQ signals corresponding to the number of initial transmissions for the transport block. In this case, the BLER value may be generated by dividing the number of NACK signals for the total number of initial transmissions by the total number of initial transmissions.

[0057] As an example, when the base station (100) generates a BLER value based on time, the base station (100) may generate a BLER value based on HARQ signals received in a specific time range before any transmission point in time. In this case, the BLER value may be calculated by dividing the number of NACK signals for initial transmissions received in a specific time range by the total number of initial transmissions within the specific time range.

[0058] As an example, the base station (100) may generate a BLER value based on at least one of a HARQ signal corresponding to URLLC data and / or a HARQ signal corresponding to a padding signal. For example, the base station (100) may generate a BLER value by considering only the HARQ signal corresponding to the URLLC data. In addition, the base station (100) may generate a BLER value by considering only the HARQ signal corresponding to the padding signal. In addition, the base station (100) may generate a BLER value by considering the HARQ signal corresponding to URLLC and the HARQ signal corresponding to the padding signal.

[0059] In operation 318, the base station (100) can correct the OLRC offset based on the HARQ signal received from the UE (200) and generate a correction constant for the SINR based on the generated BLER value. Operation 318 is described below.

[0060] The base station (100) determines the OLRC offset ( OLRC ) and can compensate for the SINR estimated based on the CQI or the SINR applied to the previous transmission. The base station (100) can adjust the OLRC offset ( OLRC ) to increase ( up ) or reduce( down ) can be made. The related [Mathematical Formula 1] is as follows.

[0061] [Mathematical Formula 1]

[0062]

[0063] Here, SINR CQI represents the SINR value estimated from CQI, and SINR HARQcan represent the SINR value corrected by the HARQ signal. That is, SINR HARQ is SINR CQI and OLRC offset ( OLRC ) is generated based on the OLRC offset ( OLRC ) increases or decreases depending on the HARQ signal (ACK / NACK). For example, if the HARQ signal is ACK, the base station (100) increases or decreases the existing OLRC offset. up and if the HARQ signal is NACK, the existing OLRC offset is increased. down It can be reduced by that much.

[0064] The increase in OLRC offset according to HARQ signal ( up ) and the decrease in magnitude ( down ) can be determined as in [Mathematical Formula 2].

[0065] [Equation 2]

[0066]

[0067] Here, BLERt can represent the target BLER value.

[0068] As an example, the base station (100) calculates an OLRC offset ( OLRC offset) based on a received HARQ signal corresponding to a padding signal (or dummy signal, dummy data, etc.). OLRC ) and can compensate for the SINR estimated based on the CQI or the SINR applied for the previous transmission. The base station (100) can adjust the OLRC offset ( ) depending on whether the HARQ signal corresponding to the padding signal is ACK / NACK. OLRC ) to increase ( up ) or reduce( down) can be made. The related [Mathematical Formula 3] is as follows.

[0069] [Equation 3]

[0070]

[0071] If the HARQ signal corresponding to the dummy signal is ACK, the base station (100) sets the existing OLRC offset. up and if the HARQ signal corresponding to the dummy signal is NACK, the existing OLRC offset is increased. down It can be reduced by that much.

[0072] As an example, the base station (100) determines an OLRC offset ( OLRC offset) based on a HARQ signal received corresponding to URLLC data. OLRC ) and can compensate for the SINR estimated based on the CQI or the SINR applied for the previous transmission. The base station (100) can compensate for the OLRC offset ( ) depending on whether the HARQ signal corresponding to the URLLC data (specifically, the transport block including the URLLC data) is ACK / NACK. OLRC ) to increase ( up ) or reduce( down ) can be made. The related [Mathematical Formula 4] is as follows.

[0073] [Equation 4]

[0074]

[0075] If the HARQ signal corresponding to URLLC data is ACK, the base station (100) uses the existing OLRC offset. up If the HARQ signal corresponding to the URLLC data is NACK, the existing OLRC offset is increased. down It can be reduced by that much.

[0076] Since the target BLER in [Mathematical Formula 3] and [Mathematical Formula 4] is the same, the increase and decrease of the OLRC offset are the same.

[0077] For URLLC (ultra reliable low latency communication) data, the target BLER is very low. _up and The difference in _down is large. For example, if the target BLER is 10 -5 If, _up is 10 -5 can be set to _down becomes a value close to 1 (see Equation 2). The increase in the ACK signal is The _up value is small and is the reduction amount for the NACK signal. Since _down is relatively large, it takes a long time for the corrected SINR value to converge to an accurate value. Consequently, performance degradation in terms of throughput and resource efficiency may occur in URLLC environments. The following describes the behavior of the base station in relation to this performance degradation.

[0078] In operation 318, the base station (100) can generate a correction constant for SINR based on the generated BLER value. The operation of the base station (100) generating a correction constant for SINR based on the generated BLER value can be based on [Mathematical Expression 5] and / or [Mathematical Expression 6].

[0079] [Equation 5]

[0080]

[0081] SINR HARQ can be compensated based on the compensation constant α. SINR eff represents a corrected effective SINR value. The base station (100) can determine the MCS based on the effective SINR value and transmit data.

[0082] Referring to [Equation 5], as α increases, SINR eff As the value decreases, the base station (100) conservatively determines the MCS, and errors in the transmission blocks transmitted by the base station (100) can be suppressed. On the other hand, as α decreases, the SINR eff As the value increases, the base station (100) can aggressively determine the MCS, and resource efficiency can increase at the expense of an increased probability of error occurrence for transmission blocks transmitted by the base station (100).

[0083] The correction constant α can be generated based on the difference between the BLER value generated at the time of transmission and the target BLER value. If the BLER value at the time of transmission is greater than the target BLER value, the SINR value estimated by the base station (100) is higher than the actual SINR value, indicating that the base station (100) applies an aggressive MCS. If the BLER value at the time of transmission is lower than the target BLER value, the SINR value estimated by the base station (100) is lower than the actual SINR value, indicating that the base station (100) applies a conservative MCS.

[0084] The correction constant α can be adaptively modified by using the difference between the BLER value generated at the time of transmission (however, if an error has not yet occurred, the BLER value can be replaced with a predefined value) and the target BLER value. The correction constant α can be generated based on the BLER value generated by the base station (100) in operation 316.

[0085] As an example, the correction constant α can be generated based on [Mathematical Formula 6].

[0086] [Equation 6]

[0087]

[0088] Here, BLER is the BLER value at the time of transmission, and BLERt represents the target BLER. η is a weight multiplied by the difference between the BLER value and the target BLER value. Specifically, η may be a weight multiplied by the difference between the log value of the BLER value and the log value of the target BLER value. The difference between the log value of the BLER value and the log value of the target BLER value may represent the difference between the BLER value and the target BLER value.

[0089] The base station (100) can generate a BLER value by considering only the HARQ signal for URLLC data, or can generate a BLER value by considering the HARQ signal for URLLC data and padding signal (or padding data, dummy data, etc.) together.

[0090] Referring to [Mathematical Formula 6], the correction constant α can be a larger or smaller value than before based on the difference between the BLER value and the target BLER value. Furthermore, the correction constant α can vary in a large or small range based on the difference between the BLER value and the target BLER value.

[0091] Referring to [Mathematical Formula 5], as the correction constant α increases, the SINR eff As the value decreases and the base station (100) conservatively determines and transmits the MCS, the BLER value can converge closer to the target BLER as the error rate decreases. Conversely, as the correction constant α decreases, the SINR eff As the value increases and the base station (100) aggressively determines and transmits the MCS, the BLER value will converge closer to the target BLER as the error rate increases.

[0092] In operation 320, the base station (100) can correct the SINR based on the corrected OLRC offset and the correction constant α, and determine the MCS based on the corrected SINR. Here, the corrected SINR is the SINR of [Mathematical Formula 5]. eff can be expressed.

[0093] In operations 322 and 324, the base station (100) can configure a data transmission block based on the determined MCS and transmit URLLC data or a padding signal to the UE (200) through the configured data transmission block.

[0094] And, a series of processes according to operations 312 to 314 can be repeatedly performed at the base station (100) or UE (200).

[0095] FIG. 4 illustrates a method performed by a user equipment (UE) according to one embodiment of the present disclosure. The operations of the UE illustrated in FIG. 4 may correspond to the operations performed by the UE (200) in FIG. 3 . The operations of FIG. 4 may be performed by the UE (1800) in FIG. 18 .

[0096] Referring to FIG. 4, in operation 402, the UE measures SINR (operation 302 of FIG. 3), and in operation 404, the UE may transmit a channel quality indicator (CQI) to the base station (operation 304 of FIG. 3). The CQI (channel quality indicator) may include information about the measured SINR.

[0097] At operation 406, the UE receives first URLLC data from the base station (operation 310 of FIG. 3), at operation 408, the UE performs an error check (or cyclic redundancy check) on the first URLLC data (operation 312 of FIG. 3), and may transmit a first HARQ signal to the base station (operation 314 of FIG. 3). Here, the first HARQ signal may include an ACK signal or a NACK signal based on the error check result on the first URLLC data.

[0098] In operation 410, the UE may receive a padding signal (or padding data, dummy data, dummy signal, etc.) from the base station. (Operation 310 of FIG. 3)

[0099] In operation 412, the UE may perform an error check (or cyclic redundancy check) on the received padding signal and transmit a second HARQ signal to the base station based on the error check result. (Operations 312 and 314 of FIG. 3)

[0100] At operation 414, the UE may receive second URLLC data from the base station. (Operation 324 of FIG. 3)

[0101] The UE can transmit a HARQ signal to the base station in response to URLLC data or padding signals received from the base station. The base station can generate a BLER value and compensate for the SINR based on the HARQ signal received from the UE, and transmit the URLLC data or padding signal to the UE based on the MCS determined by the compensated SINR.

[0102] FIG. 5 illustrates a method performed by a base station according to one embodiment of the present disclosure. The operations of the base station illustrated in FIG. 5 may correspond to the operations performed by the base station (100) in FIG. 3 . The operations of FIG. 5 may be operations performed by the base station (1900) in FIG. 19 .

[0103] In operation 502, the base station may receive a CQI from the UE. The CQI may include an SINR value measured by the UE. (Operation 304 of FIG. 3)

[0104] In operation 504, the base station may estimate an SINR value based on the CQI received from the UE and determine an MCS based on the estimated SINR value. (Operation 306 of FIG. 3)

[0105] In operation 506, the base station may transmit the first URLLC data to the UE based on the determined MCS (operations 308 and 310 of FIG. 3).

[0106] At operation 508, the base station may receive a first HARQ signal corresponding to the first URLLC data from the UE. (Operation 314 of FIG. 3)

[0107] At step 510, the base station may transmit a padding signal to the UE. (Step 310 of FIG. 3) The padding signal may be transmitted at a regular interval between URLLC data traffic. The period at which the base station transmits the padding signal may be set based on a preset value. The transmission period of the padding signal may be adaptively changed based on channel conditions.

[0108] For example, the transmission period of the padding signal can be changed based on the rate of change in channel conditions or the difference between the current error rate and the target error rate. If the channel conditions change rapidly or the difference between the current error rate and the target error rate is greater than a certain threshold, the transmission period of the padding signal can be set shorter. In other words, the base station can transmit the padding signal to the user terminal more frequently.

[0109] At operation 512, the base station may receive a second HARQ signal for the padding signal (operation 314 of FIG. 3).

[0110] In operation 514, the base station may generate a BLER value. (Operation 316 of FIG. 3) The base station may generate the BLER value based on the HARQ signal from the first transmission time (the first transmission time after receiving the CQI from the UE) to any transmission time. Furthermore, the base station may generate the BLER value by considering a plurality of HARQ signals within a specific range before any transmission time. In this case, the specific range may be defined based on the number and / or time of initial transmission for a transport block. Furthermore, the specific range may be defined by the base station generating and storing an index for a NACK signal, adding 1 to the index value for the NACK signal whenever it receives a HARQ signal for URLLC data, and generating a BLER value when the index value for the NACK signal exceeds a preset parameter value. In other words, the specific range may be determined by comparing the index value for the NACK signal with the preset parameter value.

[0111] In operation 516, the base station can generate a correction constant based on the generated BLER value. (Operation 318 of FIG. 3)

[0112] At operation 518, the base station may correct the OLRC offset based on the second HARQ signal. (Operation 318 of FIG. 3)

[0113] At operation 520, the base station can compensate the SINR based on the compensated ORC offset and compensation constant. (Operation 320 of FIG. 3)

[0114] At operation 522, the base station may transmit second URLLC data to the UE based on the MCS determined based on the corrected SINR (operations 322 and 324 of FIG. 3).

[0115] FIG. 6 illustrates a method performed by a base station according to one embodiment of the present disclosure. Specifically, FIG. 6 illustrates operations of the base station between a first URLLC data transmission operation and a second URLLC data transmission operation. The operations of FIG. 6 may be operations performed by the base station (1900) of FIG. 19.

[0116] In operation 602, the base station transmits first URLLC data to the UE based on the first time resource and the first frequency resource. The base station can determine an MCS based on the estimated SINR value and send the first URLLC data based on the determined MCS. At this time, the base station can receive a CQI from the UE and estimate an SINR value based on the received CQI.

[0117] In operation 604, the base station transmits a padding signal based on a second time resource and a first frequency resource. Here, the first time resource and the second time resource represent different time resources. Here, the second time resource is a time resource after the first time resource and may include a plurality of time resources configured periodically. That is, the base station may periodically transmit a padding signal to the UE using the second time resource. At this time, the period for transmitting the padding signal may be based on a preset value. In addition, the period for transmitting the padding signal may be adaptively changed based on the channel condition.

[0118] In operation 606, the base station receives a first HARQ signal for a padding signal from the UE. The first HARQ signal may include an ACK signal or a NACK signal. If the second time resource is composed of a plurality of periodic time resources, the first HARQ signal may represent an HARQ signal based on a padding signal for the last time resource among the time resources included in the second time resource.

[0119] In operation 608, the base station may generate a BLER value. (Operation 316 of FIG. 3) The base station may generate the BLER value based on the HARQ signal received from the first transmission time (the first transmission time after receiving the CQI from the UE) to any transmission time (e.g., another transmission time after the first transmission time). For example, the base station may generate the BLER value based on all NACK signals generated between the time of receiving the CQI from the UE and any transmission time. In this case, the NACK signal may be based on at least one of a NACK signal for the first URLLC data and a NACK signal for the padding signal. That is, the base station may generate the BLER value based on the HARQ signal for the URLLC data and / or the HARQ signal for the padding signal.

[0120] In addition, the base station can generate a BLER value by considering a plurality of HARQ signals within a specific range before any transmission point in time. For example, the base station can generate a BLER value based on a NACK signal for transport blocks that fall within a specific range among transport blocks transmitted between the time of receiving the CQI from the UE and any transmission point in time (e.g., another transmission point after the first transmission point in time). The NACK signal can be based on at least one of a NACK signal for the first URLLC data and a NACK signal for the padding signal. That is, the base station can generate a BLER value based on the HARQ signal for the URLLC data and / or the HARQ signal for the padding signal. In addition, the specific range can be defined based on the number and / or time of initial transmissions for the transport block. In addition, the specific range can be defined based on a comparison of an index value for the NACK signal with a preset parameter value. (See FIG. 9)

[0121] In operation 610, the base station may generate a correction constant for the SINR based on the generated BLER value. (Operation 318 of FIG. 3) At this time, the base station may generate a correction constant for the SINR based on the difference between the generated BLER value and the target BLER value. In addition, the base station may generate the correction constant by applying a weight to the difference between the generated BLER value and the target BLER value. Here, the value of the correction constant increases as the BLER value is larger than the previous correction constant, and the corrected SINR (or, effective SINR) decreases as the correction constant increases. (See Equations 5 and 6)

[0122] In operation 612, the base station may correct the OLRC offset based on the first HARQ signal (see Equations 1, 3, and 4).

[0123] In operation 614, the base station can compensate the SINR based on the compensated OLRC offset and compensation constant (see Equations 5 and 6).

[0124] In operation 616, the base station may transmit second URLLC data to the UE based on the MCS determined based on the corrected SINR, based on a third time resource and a first frequency resource. In this case, the third time resource may indicate a time resource subsequent to the second time resource in operation 604.

[0125] FIG. 7 is a graph showing the difference between a generated BLER and a target BLER according to one embodiment of the present disclosure.

[0126] Referring to Fig. 7, a graph showing the BLER of URLLC data over time is illustrated. At point 1 on the graph, the BLER value is greater than the target BLER value. Therefore, at point 1, the SINR correction constant α increases by [Mathematical Formula 6]. Therefore, by [Mathematical Formula 5], the effective SINR value generated compared to SINR_HARQ generated based on the HARQ signal is greatly reduced, and since the effective SINR value is reduced, the base station conservatively determines the MCS. Consequently, since the block error rate of the transmission blocks transmitted from the base station is reduced, the BLER value can approach the target BLER value.

[0127] On the other hand, at point 2 on the graph, the BLER value is smaller than the target BLER value. Therefore, at point 2, the SINR correction constant α is reduced by [Equation 6]. Therefore, by [Equation 5], the generated effective SINR value is only slightly smaller than SINR_HARQ generated based on the HARQ signal. Therefore, compared to point 1, the base station determines the MCS more aggressively. As a result, the block error rate of the transmission blocks transmitted from the base station increases, so the BLER value can approach the target BLER value. In other words, at point 2, the base station can increase the throughput by aggressively selecting the MCS.

[0128] According to one embodiment, a method can rapidly change the SINR by adjusting the amount of change in the correction constant α based on the difference between the BLER value and the target BLER value. Therefore, the BLER value can quickly converge to the target BLER value. Furthermore, as the difference between the BLER value and the target BLER value decreases, the amount of change in the correction constant decreases, so that the BLER value can stably converge to the target BLER value.

[0129] FIG. 8 illustrates a method for generating (or calculating) a correction constant according to one embodiment of the present disclosure.

[0130] Figure 8 illustrates a method for generating a BLER value and a correction constant for SINR by reflecting all accumulated errors from the initial transmission time (e.g., the initial transmission time after receiving a CQI from a UE) to an arbitrary transmission time t by a base station. The base station can update the SINR correction constant α over time while allocating less data capacity based on an infinite impulse response (IIR) method.

[0131] Referring to FIG. 8, in operation 802, the base station increases the value indicating the number of URLLC data by +1 when receiving a HARQ signal for new URLLC data. Then, in operation 804, the base station determines whether the HARQ signal for new URLLC data is a NACK signal (operation 804-1), and if it is a NACK signal, increases the value indicating the number of NACKs by +1 (operation 804-2). Then, in operation 806, the base station can generate a BLER value by dividing the value indicating the number of NACKs by the value indicating the number of URLLC data.

[0132] By operation 802 and operation 804, the base station can know the number of all URLLC data transmitted up to an arbitrary transmission time t and the number of NACK signals. That is, the number of all accumulated NACK signals can be reflected in generating a BLER value. In operation 808, the base station can generate a new correction constant α(t+1) based on the generated BLER value and the previous correction constant α(t). f(BLER) can represent [log10(BLER) - log10(BLERt)] as shown in [Mathematical Formula 6].

[0133] In one embodiment, operations 802 to 808 may be performed on URLLC data and / or a padding signal (or a dummy signal, dummy data, etc.). For example, the base station may generate a BLER value based on the URLLC data and a NACK signal for the URLLC data. Furthermore, the base station may generate a BLER value based on the URLLC data and the padding signal, a NACK signal for the URLLC data, and a NACK signal for the dummy signal. Furthermore, the base station may generate a BLER value based on the dummy signal and a NACK signal for the dummy signal.

[0134] FIG. 9 illustrates a method for generating (or calculating) a correction constant according to one embodiment of the present disclosure.

[0135] Figure 9 illustrates a method in which a base station generates a BLER value by reflecting a specific range of errors prior to any transmission point in time and generates a correction constant for SINR.

[0136] In one embodiment, when the base station receives a NACK signal for URLLC data, the base station may generate an index for the corresponding NACK signal. For example, when the base station receives a first NACK signal, the base station may generate an index for the first NACK signal with a value of 1. Then, the base station may add 1 to the value of the index for the generated first NACK signal whenever it receives a HARQ signal for the next URLLC data. (Operation 904) The base station may compare the value of the index for the first NACK signal with a preset parameter value (windowSize in FIG. 9). (Operation 906) Then, if the value of the index for the first NACK signal is greater than the preset parameter value, the base station may generate the number of NACK signals generated up to that point (Operation 908), and the base station may generate a BLER value based on the number of generated NACK signals and the preset parameter value (windowSize in FIG. 9). (Operation 910) Then, the base station may update a correction constant for SINR based on the generated BLER value. (912 Operation) Such an operation can be performed with a small amount of memory consumption due to the characteristics of URLLC data with a small number of NACK signals. That is, when the base station reflects a certain range of errors before any transmission point, the certain range can be set based on a comparison of the index value for the NACK signal with a preset parameter value.

[0137] In Fig. 9, idx(NACKn) represents the index of NACKn. The base station can store the index of NACK when the HARQ signal for new URLLC data is a NACK signal. Then, the base station can update the stored index value of NACK by adding 1 whenever receiving a HARQ signal for URLLC data. Then, the base station can increase the number of existing NACKs and update them when the HARQ signal for URLLC data is a NACK signal. If the index value of the NACK with the largest value exceeds a set parameter (window size), the number of NACK signals can be updated by decreasing the number of NACK signals. Then, the index of the corresponding NACK can be removed. The base station can generate a BLER value by dividing the number of generated NACKs by the set parameter (window size). Then, the base station can update the SINR correction constant α(t) based on the generated BLER value. The memory required for such an operation is the maximum number of NACKs, the BLER value, and the correction constant for SINR. That is, since the number of NACKs is small due to the nature of URLLC data, it may not consume a large amount of memory.

[0138] Below, FIGS. 10 to 17 describe examples and effects according to the above-described embodiments.

[0139] In Figures 10 to 17, the horizontal axis of the graphs represents the URLLC index, and the vertical axis represents the BLER value. It can be understood that the URLLC index value increases over time. Therefore, the graphs can be understood as representing the BLER value over time.

[0140] As indicators for evaluating the performance of embodiments of the present disclosure, BLER values ​​and PRB (physical resource blocks) are used. PRB represents the amount of resources used to configure a set transmission block, and a smaller value means using fewer resources.

[0141] The experimental setup is as follows. The base station and terminal have eight and two antennas, respectively, and the subcarrier spacing and carrier frequency for data transmission are set to 30 kHz and 4 GHz, respectively. URLLC data and padding signals are allocated to resource blocks (RBs) of approximately 100 bytes per MCS, forming transmission blocks.

[0142] The target BLER value of URLLC data and padding signal is 10 -4 (0.01%), and when the base station corrects the ORLC offset, the increase and decrease of the ORLC offset are set to 0.0001 dB and 0.9999 dB, respectively. The terminal is assumed to be moving at 30 km / h. The channel model between the base station and the terminal uses the CDL-B model in the NR system. In the simulation, the actual SINR is 10 dB, and the SINR estimated by the base station is assumed to be 0 dB, so that the difference between the actual SINR and the initially estimated SINR is set. The URLLC data traffic is generated based on the FTP model 3 (Poisson arrival process) so that a total of 105 data follow the average transmission period of 1000 TTI. The transmission period of the padding signal is 100 TTI. The weight of the SINR correction constant, η, is 10 -4 and 10 -3 is applied.

[0143] FIG. 10 and FIG. 11 are graphs showing BLER values ​​according to one embodiment of the present disclosure.

[0144] Figures 10 and 11 illustrate the results of using a link adaptation method using padding signals (or dummy signals, dummy data, etc.) and BLER values ​​generated at the time of transmission. The graph illustrated in Figure 10 represents the results using BLER values ​​that reflect all errors that occurred from the first transmission time to any arbitrary transmission time, while the graph illustrated in Figure 11 represents the results using BLER values ​​that reflect only errors that occurred within a specific range.

[0145] The No dummy graph represents the case where the BLER value at the time of transmission is not used. The No dummy 1 graph uses the BLER value at the time of transmission and the weight (η) is 10. -4 This is a graph showing the results when the correction constant for SINR is updated by applying . No dummy 2 graph uses the BLER value at the time of transmission, and the weight (η) is 10. -3 This is a graph showing the results when the correction constant for SINR is updated by applying .

[0146] Referring to FIGS. 10 and 11, the No dummy graph confirms that the base station continuously transmits data conservatively, resulting in a slow channel convergence speed and a BLER value that is continuously lower than the target BLER value.

[0147] On the other hand, the No dummy 1 and No dummy 2 graphs have a target BLER value of 10 -4 It is confirmed that the convergence speed is improved. In addition, it is confirmed through the No dummy 1 and No dummy 2 graphs that the weight (η) is related to the convergence performance. By updating the SINR correction constant based on the BLER value at the time of transmission, the convergence performance to the target BLER value can be improved.

[0148] [Table 1] shows the PRB values ​​related to FIGS. 10 and 11. Option 1 represents the case where a BLER value that reflects errors that occurred from the first transmission time to an arbitrary transmission time is used. Option 2 represents the case where a BLER value that reflects errors that occurred within a specific range is used. Referring to [Table 1], it can be seen that resource efficiency is improved because the cases of No dummy 1 and No dummy 2 show lower PRB values ​​than the No dummy.

[0149]

[0150] FIGS. 12 and 13 are graphs showing BLER values ​​according to one embodiment of the present disclosure. In FIGS. 12 and 13, the No dummy, No dummy 1, and No dummy 2 graphs are identical to those in FIG. 10. In FIGS. 12 and 13, the URLLC & dummy graphs show the results when a base station periodically transmits a padding signal (or a dummy signal, dummy data, etc.) and updates a correction constant α for SINR using the BLER value at the time of transmission.

[0151] Additionally, Fig. 12 is a graph showing a case where errors in both URLLC data and padding signals are reflected when the base station generates a BLER value. Fig. 13 is a graph showing a case where errors in only URLLC data are reflected when the base station generates a BLER value.

[0152] Referring to Figures 12 and 13, the URLLC & dummy graphs exhibit high convergence performance, effectively converging to the target BLER value even when different values ​​are applied to the weights (η). In other words, they exhibit more robust performance with respect to weights.

[0153] [Table 2] shows the PRB values ​​for URLLC data for No dummy 1 and No dummy 2 of Fig. 10, and URLLC & dummy of Figs. 12 and 13. Here, Option 3 is the case where errors in both URLLC data and padding signals are reflected (in the case of Fig. 12), and Option 4 is the case where only errors in URLLC data are reflected (in the case of Fig. 13).

[0154]

[0155] Referring to [Table 2], compared to the No Dummy case, the PRB values ​​are smaller in Option 3 and Option 4, and the difference in PRB values ​​is also smaller when the weight values ​​change. Therefore, the efficiency of resource use and robustness to weight values ​​are confirmed.

[0156] Figures 14 and 15 are graphs illustrating BLER values ​​according to one embodiment of the present disclosure. Figures 14 and 15 illustrate a case where a base station updates the SINR correction constant α using a BLER value that reflects only a specific range of errors prior to the transmission point. Other settings are the same as in Figure 12.

[0157] Figure 14 shows the results reflecting errors for URLLC data and padding signals within a specific range when a base station generates a BLER value, and Figure 15 shows the results reflecting only errors for URLLC data within a specific range when a base station generates a BLER value.

[0158] The No dummy, No dummy 1, and No dummy 2 graphs of FIGS. 14 and 15 are expressed identically to the graph of FIG. 11 for comparison.

[0159] Referring to Figures 14 and 15, even when the base station generates a BLER value by reflecting errors within a specific range prior to the transmission time, the performance of the BLER value converging to the target BLER value is improved. In addition, it is confirmed that the performance is robust to the weight (η).

[0160] [Table 3] shows the PRB values ​​for URLLC data for No dummy 1 and No dummy 2 of Fig. 10, and URLLC & dummy of Figs. 14 and 15. Here, Option 5 is the case where errors in both URLLC data and padding signals are reflected (in the case of Fig. 14), and Option 6 is the case where only errors in URLLC data are reflected (in the case of Fig. 15).

[0161]

[0162] FIG. 16 and FIG. 17 are graphs showing BLER values ​​according to one embodiment of the present disclosure.

[0163] Figures 16 and 17 illustrate the change in BLER when the SINR of the channel changes abruptly when the base station transmits a padding signal. In Figures 16 and 17, the SINR value decreases abruptly from 10 dB to -5 dB in the middle of the URLLC index. In other words, a situation is assumed where the channel condition deteriorates rapidly.

[0164] Figure 16 illustrates a case where a base station generates BLER by reflecting errors in URLLC data and padding signals (or dummy signals, dummy data, etc.) that occurred from the first transmission point (the first transmission point after receiving CQI from the UE) to an arbitrary transmission point, and updates a correction constant for SINR.

[0165] Figure 17 illustrates a case where a base station generates (or calculates) a BLER value by reflecting an error that occurred in a specific range (windowSize 10000) before the transmission time and updates a correction constant for SINR.

[0166] In Figures 16 and 17, the No dummy graph represents a graph when the base station does not transmit a padding signal (or dummy signal, dummy data, etc.), and the No dummy (η=10 -3 ) graph represents the case where the base station does not transmit a padding signal, but generates a BLER value at the time of transmission to update the correction constant for SINR. The URLLC & dummy graph represents the case where the base station transmits a padding signal, generates a BLER value at the time of transmission, and updates the correction constant for SINR.

[0167] Referring to FIGS. 16 and 17, in the case of the No dummy graph, when the channel condition deteriorates rapidly, the SINR estimated for the relatively good channel condition cannot quickly change to the SINR of the deteriorated condition, so the error increases rapidly. As a result, the BLER value becomes higher than the target BLER value. On the other hand, in the case of the URLLC & dummy graph, even if the channel condition deteriorates rapidly, the BLER value does not increase rapidly and converges to the target BLER value because an appropriate SINR value is estimated based on the HARQ signal for the padding signal.

[0168] [Table 4] No dummy (10) of Figs. 16 and 17 -3 ), URLLC & dummy(10 -3) shows the PRB value for URLLC data. Here, Option 7 is the case where the BLER value is generated by reflecting all errors up to the time of transmission (case of Fig. 16), and Option 8 is the case where the BLER value is generated by reflecting only a specific range of errors before the time of transmission (case of Fig. 17).

[0169]

[0170] Referring to [Table 4], it is confirmed that URLLC & dummy has a smaller PRB value than No dummy in Option 7 and Option 8. That is, it is confirmed that resource efficiency is high when the base station transmits a padding signal, generates a BLER value, and updates the correction constant for SINR based on the generated BLER value.

[0171] FIG. 18 illustrates components of a UE (1800) according to one embodiment of the present disclosure.

[0172] Referring to FIG. 18, a user equipment (UE) (1800) according to one embodiment includes a transceiver (1810), a processor (1830) connected to the transceiver (1810), and a memory (1820) connected to the processor (1830). The UE (1800) of FIG. 18 can perform the operations described in FIGS. 3 and 4.

[0173] The UE (1800) may include more or fewer components than those described above. Additionally, the transceiver (1810), processor (1830), and memory (1820) may be implemented as a single chip.

[0174] The transceiver (1810) collectively refers to a receiver and a transmitter, and can transmit and receive with a base station (base station). The information transmitted and received may include control information and data. For example, information on a Channel Quality Indicator (CQI) or measured SINR may be transmitted from a user equipment (UE) to a base station (1900) through the transceiver (1810), and URLLC data or padding signals according to embodiments of the present disclosure may be received by a user through the transceiver (1810). The transceiver (1810) may include an RF transmitter for up-converting and amplifying a frequency of a transmission signal, and an RF receiver for low-noise amplifying and down-converting a frequency of a reception signal. However, this is merely an example of the transceiver (1810), and the components of the transceiver (1810) are not limited to an RF transmitter and an RF receiver. The transceiver (1810) can receive a signal through a wireless channel and output it to the processor (1830), and can transmit a signal output from the processor (1830) through the wireless channel.

[0175] The memory (1820) can store programs and data necessary for the operation of the device. In addition, the memory (1820) can store control information or data included in signals acquired from the device. The memory (1820) can be a storage medium such as a read-only memory (ROM), a random access memory (RAM), a hard disk, a CD-ROM, a DVD, or a combination of storage media.

[0176] The processor (1830) can control a series of processes so that the device operates as described above. For example, the transceiver (1810) can receive a data signal containing a message transmitted from a user, and the processor (1830) can check the result of receiving the transmitted data signal.

[0177] FIG. 19 illustrates components of a base station (1900) according to one embodiment of the present disclosure.

[0178] Referring to FIG. 19, a base station (1900) includes a transceiver (1910), a processor (1930) connected to the transceiver (1910), and a memory (1920) connected to the processor (1930). The base station (1900) of FIG. 19 can perform the operations described in FIGS. 3 to 6.

[0179] The base station (1900) may include more or fewer components than those described above. Additionally, the transceiver (1910), processor (1930), and memory (1920) may be implemented as a single chip.

[0180] The transceiver (1910) collectively refers to a receiver and a transmitter, and can transmit and receive with a user's terminal (1800). The information transmitted and received may include control information and data. For example, information on CQI generated by the user and measured SINR may be received by the base station (1900) through the transceiver (1910), and URLLC data or padding signals (or dummy signals, dummy data, etc.) may be transmitted to the user through the transceiver (1910). The transceiver (1910) may include an RF transmitter for up-converting and amplifying the frequency of a transmission signal, and an RF receiver for low-noise amplifying and down-converting the frequency of a reception signal. However, this is only an example of the transceiver (1910), and the components of the transceiver (1910) are not limited to the RF transmitter and the RF receiver. The transceiver (1910) can receive a signal through a wireless channel and output it to the processor (1930), and can transmit a signal output from the processor (1930) through the wireless channel.

[0181] The memory (1920) can store programs and data necessary for the operation of the device. In addition, the memory (1920) can store control information or data included in signals obtained from the device. The memory (1920) can be a storage medium such as a read-only memory (ROM), a random access memory (RAM), a hard disk, a CD-ROM, a DVD, or a combination of storage media.

[0182] The processor (1930) can control a series of processes so that the device operates as described above. For example, the transceiver (1910) can receive a data signal containing a message transmitted from a user, and the processor (1930) can check the result of receiving the transmitted data signal.

[0183] According to various embodiments of the present disclosure, the BLER value for URLLC data can rapidly converge to the target BLER value. Furthermore, the efficiency of resource utilization for transmitting URLLC data is increased. Accordingly, adaptive performance can be improved, such as estimating an SINR value according to rapidly changing channel conditions and transmitting data based on an appropriate MCS. Furthermore, the method and device according to embodiments of the present disclosure are robust to weight values ​​for updating correction constants for SINR. Therefore, effective performance can be achieved with appropriate weight values, thereby facilitating the application of the technology.

[0184] The various embodiments of the present disclosure and the terminology used therein are not intended to limit the technical features described in the present disclosure to specific embodiments, but should be understood to include various modifications, equivalents, or substitutes of the embodiments. In connection with the description of the drawings, similar reference numerals may be used for similar or related components. The singular form of a noun corresponding to an item may include one or more items, unless the relevant context clearly indicates otherwise. In the present disclosure, each of the phrases "A or B," "at least one of A and B," "at least one of A or B," "A, B, or C," "at least one of A, B, and C," and "at least one of A, B, or C" can include any one of the items listed together in the corresponding phrase among the phrases, or all possible combinations thereof. Terms such as "first," "second," or "first" or "second" may be used merely to distinguish one component from another and do not limit the components in any other respect (e.g., importance or order). When a component (e.g., a first component) is referred to as "coupled" or "connected" to another component (e.g., a second component), with or without the terms "functionally" or "communicatively," it means that the component can be connected to the other component directly (e.g., wired), wirelessly, or through a third component.

[0185] The term "module" as used herein may include a unit implemented in hardware, software, or firmware, and may be used interchangeably with terms such as logic, logic block, component, or circuit. A module may be an integrally formed component or a minimum unit or part of a component that performs one or more functions. For example, according to one embodiment, a module may be implemented in the form of an application-specific integrated circuit (ASIC).

[0186] Various embodiments of the present disclosure may be implemented as software (e.g., a program (140)) including one or more commands stored in a storage medium (e.g., an internal memory (136) or an external memory (138)) readable by a machine (e.g., an electronic device (101)). For example, a device (e.g., a processor (e.g., processor (120) of an electronic device (101)) can call at least one command from among one or more commands stored from a storage medium and execute it. This enables the device to operate to perform at least one function according to the called at least one command. The one or more commands may include code generated by a compiler or code executable by an interpreter. A storage medium readable by the device may be provided in the form of a non-transitory storage medium. Here, 'non-transitory' only means that the storage medium is a tangible device and does not contain a signal (e.g., EM wave), and this term does not distinguish between cases where data is stored semi-permanently and cases where it is stored temporarily in the storage medium.

[0187] According to one embodiment, the method according to various embodiments disclosed in the present disclosure may be provided as included in a computer program product. The computer program product may be traded as a product between a seller and a buyer. The computer program product may be distributed in the form of a device-readable storage medium (e.g., a compact disc read-only memory (CD-ROM)), or may be distributed online (e.g., downloaded or uploaded) via an application store (e.g., Play Store™) or directly between two user devices (e.g., smartphones). In the case of online distribution, at least a portion of the computer program product may be temporarily stored or temporarily generated in a device-readable storage medium, such as the memory of a manufacturer's server, an application store's server, or an intermediary server.

[0188] According to various embodiments, each component (e.g., a module or a program) of the described components may include one or more entities. According to various embodiments, one or more components or operations of the aforementioned components may be omitted, or one or more other components or operations may be added. Alternatively or additionally, a plurality of components (e.g., a module or a program) may be integrated into a single component. In such a case, the integrated component may perform one or more functions of each of the plurality of components identically or similarly to those performed by the corresponding component among the plurality of components prior to integration. According to various embodiments, the operations performed by a module, program, or other component may be executed sequentially, in parallel, iteratively, or heuristically, or one or more of the operations may be executed in a different order, omitted, or one or more other operations may be added.

Claims

1. A method performed by a base station in a wireless communication system, An operation of transmitting first URLLC data to a UE (user equipment) based on a first time resource and a first frequency resource; An operation of transmitting a padding signal to the UE based on a second time resource and the first frequency resource; An operation of receiving a first hybrid automatic repeat request (HARQ) signal for the padding signal from the UE; The action of generating a BLER (block error rate) value; An operation of generating a compensation constant for SINR (signal-to-interference-plus-noise ratio) based on the above BLER value; An operation for correcting an OLRC (outer loop rate control) offset based on the first HARQ signal; An operation of correcting the SINR based on the corrected OLRC offset and the correction constant; and An operation of transmitting second URLLC data to the UE based on a third time resource and the first frequency resource, based on a modulation and coding scheme (MCS) determined based on the compensated SINR. method.

2. In claim 1, The second time resource includes a plurality of time resources configured periodically, and the second time resource is a time resource allocated after the first time resource. The above third time resource is a time resource allocated after the above second time resource, The above first HARQ signal is based on the padding signal for the last time resource among the plurality of time resources included in the second time resource. method.

3. In claim 1, The operation of generating a correction constant based on the above BLER value is as follows: Generating the correction constant based on the difference between the above BLER value and the target BLER value, method.

4. In claim 3, The operation to generate the above BLER value is: Generating the BLER value based on all NACK signals received between the time of receiving the CQI (channel quality indicator) from the UE and the time of transmitting the second URLLC data. method.

5. In claim 4, The operation to generate the above BLER value is: Generating the BLER value based on at least one of a NACK signal for the first URLLC data and a NACK signal for the padding signal. method.

6. In claim 4, The operation of generating the above correction constant is: Generate the correction constant based on the weight applied to the difference between the BLER value and the target BLER value, The above correction constant increases as the BLER value increases, The above compensated SINR decreases as the compensation constant increases. method.

7. In claim 3, The operation of generating the above BLER (block error rate) value is as follows: Generate the BLER value based on a NACK signal for transmission blocks belonging to a specific range among the transmission blocks transmitted between the time of receiving the CQI (channel quality indicator) from the UE and the time of transmitting the second URLLC data, The above specific range is determined based on the number or time of initial transmissions for the transmission block, Generating the BLER value based on at least one of a NACK signal regarding the first URLLC data and a NACK signal regarding the padding signal. method.

8. In claim 7, The operation of generating the correction constant based on the above BLER value is: Generate the correction constant based on the weight applied to the difference between the BLER value and the target BLER value, The above correction constant increases as the BLER value increases, The above compensated SINR decreases as the compensation constant increases. method.

9. As a base station of a wireless communication system, Transmitter and receiver; processor; and Contains memory, The above memory, when executed by the processor, causes the base station to: Transmitting first URLLC data to UE (user equipment) based on the first time resource and the first frequency resource, Transmitting a padding signal to the UE based on the second time resource and the first frequency resource, Receive a first HARQ (hybrid automatic repeat request) signal for the padding signal from the UE, Generate a BLER (block error rate) value, Based on the above BLER value, a compensation constant for SINR (signal-to-interference-plus-noise ratio) is generated, Based on the first HARQ signal above, the OLRC (outer loop rate control) offset is corrected, The SINR is corrected based on the above-mentioned corrected OLRC offset and the above-mentioned correction constant, storing instructions for transmitting second URLLC data to the UE based on a third time resource and the first frequency resource based on a modulation and coding scheme (MCS) determined based on the above-mentioned compensated SINR; device.

10. In claim 9, The second time resource includes a plurality of time resources configured periodically, and the second time resource is a time resource allocated after the first time resource. The above third time resource is a time resource allocated after the above second time resource, The above first HARQ signal is based on the padding signal for the last time resource among the plurality of time resources included in the second time resource. device.

11. In claim 9, The above memory, when executed by the processor, causes the base station to: Further comprising instructions for generating the correction constant based on the difference between the BLER value and the target BLER value. device.

12. In claim 11, The above memory, when executed by the processor, causes the base station to: Further comprising an instruction to generate the BLER value based on all NACK signals received between the time of receiving the CQI (channel quality indicator) from the UE and the time of transmitting the second URLLC data. device.

13. In claim 12, The above memory, when executed by the processor, causes the base station to: Generating the BLER value based on at least one of a NACK signal for the first URLLC data and a NACK signal for the padding signal, Further comprising instructions for generating the correction constant based on a weight applied to the difference between the BLER value and the target BLER value, The above correction constant increases as the BLER value increases, The above compensated SINR decreases as the compensation constant increases. device.

14. In claim 11, The above memory, when executed by the processor, causes the base station to: Generate the BLER value based on a NACK signal for transmission blocks belonging to a specific range among the transmission blocks transmitted between the time of receiving the CQI (channel quality indicator) from the UE and the time of transmitting the second URLLC data, Further comprising instructions for generating the BLER value based on at least one of a NACK signal regarding the first URLLC data and a NACK signal regarding the padding signal, The above specific range is determined based on the number or time of initial transmissions for the transmission block. device.

15. In claim 14, The above memory, when executed by the processor, causes the base station to: Further comprising instructions for generating the correction constant based on a weight applied to the difference between the BLER value and the target BLER value, The above correction constant increases as the BLER value increases, The above compensated SINR decreases as the compensation constant increases. device.

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