Method and apparatus by which user equipment receives data block in wireless communication system

Abstract

Provided are a method and apparatus by which a user equipment receives a data block in a wireless communication system. According to the method, a user equipment: receives a first data block including a plurality of partial blocks; transmits first HARQ-ACK information indicating the number of partial blocks in which errors have occurred, from among the partial blocks; and receives a piggyback data block including at least one parity block and a second data block including new data. The user equipment transmits second HARQ-ACK information including information indicating whether or not the first data block has been successfully reconstructed on the basis of the piggyback data block and number information indicating the number of partial blocks in which errors have occurred, from among partial blocks of the second data block.

Description

Method and device for receiving data blocks by a terminal in a wireless communication system

[0001] The present disclosure relates to a wireless communication system. Specifically, the present disclosure relates to a method and device for receiving a data block by a terminal in a wireless communication system.

[0002] Wireless access systems are widely deployed to provide various types of communication services, such as voice and data. Typically, wireless access systems are multiple access systems that support communications with multiple users by sharing available system resources (e.g., bandwidth, transmission power). Examples of multiple access systems include code division multiple access (CDMA), frequency division multiple access (FDMA), time division multiple access (TDMA), orthogonal frequency division multiple access (OFDMA), and single-carrier frequency division multiple access (SC-FDMA).

[0003] In particular, as numerous communication devices demand greater communication capacity, enhanced mobile broadband (eMBB) communication technologies are being proposed, improving upon existing radio access technology (RAT). Furthermore, massive machine type communications (mMTC), which connects numerous devices and objects to provide diverse services anytime and anywhere, as well as communication systems that consider reliability and latency-sensitive services / user equipment (UE), are being proposed. Various technological configurations are being proposed for these purposes.

[0004] As the transmission speeds of wireless communication systems increase, the size of data blocks transmitted by devices increases. Accordingly, techniques have been developed to divide a single data block into multiple subblocks for transmission.

[0005] For example, a technique has been introduced in which a transmitter divides one transmission block into multiple code block groups and transmits it, and when a receiver requests retransmission in units of code block groups, the transmitter retransmits only the requested code block groups.

[0006] These transmission and retransmission procedures are managed by HARQ (Hybrid Automatic Repeat reQuest) processes. In the prior art, when a new data transmission is started through a HARQ process, the new data cannot be transmitted until all data is successfully transmitted through the transmission and retransmission procedures or until it is decided to discard data that failed to be transmitted.

[0007] Therefore, even if sufficient radio resources are available, excluding those required for retransmission, new data cannot be transmitted. This can lead to reduced transmission speeds and increased transmission delays. This problem can be particularly aggravated in time division duplex (TDD) systems, where the downlink and uplink are temporally separated.

[0008] The present disclosure provides a method and device for receiving a data block of a terminal in a wireless communication system.

[0009] The technical problems to be achieved in the present disclosure are not limited to the technical problems mentioned above, and other technical problems not mentioned will be clearly understood by a person having ordinary skill in the technical field to which the present disclosure belongs from the description below.

[0010] In one aspect, a method for receiving a data block by a terminal in a wireless communication system is provided. According to the method, the terminal receives a first data block including a plurality of partial blocks, transmits first HARQ-ACK (Hybrid Automatic Repeat reQuest-Acknowledgement) information indicating the number of partial blocks in which an error occurred among the partial blocks, receives a piggyback data block including at least one parity block and a second data block including new data, and transmits second HARQ-ACK information including 1-bit information indicating whether the first data block was successfully recovered based on the piggyback data block and count information indicating the number of partial blocks in which an error occurred among the partial blocks including the new data in the second data block.

[0011] In another aspect, a terminal for performing the above method, a device included in the terminal, and a computer readable medium (CRM) are provided.

[0012] In another aspect, a method performed by a base station in a wireless communication system is provided. According to the method, the base station transmits a first data block including a plurality of partial blocks, receives first HARQ-ACK information indicating the number of partial blocks in which errors occur among the partial blocks, transmits a piggyback data block including at least one parity block and a second data block including new data, and receives second HARQ-ACK information including 1-bit information indicating whether the first data block has been successfully recovered based on the piggyback data block and number information indicating the number of partial blocks in which errors occur among the partial blocks including the new data in the second data block.

[0013] In another aspect, a base station for performing the above method is provided.

[0014] According to the present disclosure, it is possible to increase transmission speed and reduce transmission delay by transmitting parity information and new data for recovering a previous data block in which an error occurred through one data block.

[0015] According to the present disclosure, by informing whether the previous data block has been successfully recovered based on the parity information and simultaneously feeding back the number of partial blocks in which errors occurred in the new data, problems such as a decrease in transmission speed due to retransmission and an increase in transmission delay can be improved.

[0016] According to the present disclosure, the QoS of a service requiring low-latency, ultra-high-speed transmission can be improved and system capacity can be increased.

[0017] 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 will be clearly understood by a person having ordinary skill in the art to which the present disclosure pertains from the description below.

[0018] The accompanying drawings are intended to aid in understanding the present disclosure and, together with detailed descriptions, may provide embodiments of the present disclosure. However, the technical features of the present disclosure are not limited to specific drawings, and the features disclosed in each drawing may be combined with each other to form new embodiments. Reference numerals in each drawing may indicate structural elements.

[0019] Figure 1 is a drawing showing an example of a communication system applicable to this specification.

[0020] Figure 2 is a drawing showing an example of a wireless device applicable to this specification.

[0021] FIG. 3 is a diagram illustrating a method for processing a transmission signal applicable to the present specification.

[0022] FIG. 4 is a drawing showing another example of a wireless device applicable to this specification.

[0023] FIG. 5 is a drawing showing an example of a mobile device applicable to this specification.

[0024] Figure 6 is a diagram showing physical channels applicable to this specification and a signal transmission method using them.

[0025] Figure 7 is a diagram showing the structure of a wireless frame applicable to this specification.

[0026] Figure 8 is a drawing showing a slot structure applicable to this specification.

[0027] FIG. 9 is a diagram showing an example of a communication structure that can be provided in a 6G system applicable to this specification.

[0028] Figure 10 shows an example of a perceptron structure.

[0029] Figure 11 shows an example of a multilayer perceptron structure.

[0030] Figure 12 shows an example of a deep neural network.

[0031] Figure 13 shows an example of a convolutional neural network.

[0032] Figure 14 is a diagram showing an example of a filter operation in a convolutional neural network.

[0033] Figure 15 shows an example of a neural network structure in which a recurrent loop exists.

[0034] Figure 16 shows an example of the operating structure of a recurrent neural network.

[0035] Figure 17 is a diagram showing an electromagnetic spectrum applicable to this specification.

[0036] Fig. 18 is a drawing showing a THz communication method applicable to this specification.

[0037] FIG. 19 is a diagram illustrating a THz wireless communication transceiver applicable to the present specification.

[0038] Fig. 20 is a drawing showing a THz signal generation method applicable to the present specification.

[0039] Figure 21 is a drawing showing a wireless communication transceiver applicable to this specification.

[0040] Figure 22 is a drawing showing a transmitter structure applicable to this specification.

[0041] Fig. 23 is a drawing showing a modulator structure applicable to this specification.

[0042] Figure 24 illustrates an example of a wireless interface user plane protocol stack between a terminal and a BS.

[0043] Figure 25 illustrates an example of a radio interface control plane protocol stack between a terminal and a BS.

[0044] Figures 26 and 27 illustrate feedback from a terminal and transmission from a base station in the downlink.

[0045] Figures 28 and 29 are other examples of feedback from a terminal and transmission from a base station in the downlink.

[0046] Figure 30 is an example of HARQ-ACK feedback of a terminal depending on whether PTB is transmitted.

[0047] Figures 31 and 32 illustrate the operation of a terminal receiving TB 2 in the examples of Figures 28 and 29 when decoding fails only in DCB 2-8.

[0048] Figure 33 illustrates a method for receiving a data block by a terminal in a wireless communication system.

[0049] Figure 34 illustrates a method performed by a base station in a wireless communication system.

[0050] Figure 35 illustrates a signaling process between a first device and a second device.

[0051] The following embodiments combine the components and features of this specification in a predetermined form. Each component or feature may be considered optional unless explicitly stated otherwise. Each component or feature may be implemented without being combined with other components or features. Furthermore, some components and / or features may be combined to form embodiments of this specification. The order of operations described in the embodiments of this specification may be changed. Some components or features of one embodiment may be included in another embodiment or may be replaced with corresponding components or features of another embodiment.

[0052] In the description of the drawings, procedures or steps that may obscure the gist of the present specification are not described, and procedures or steps that can be understood by a person skilled in the art are also not described.

[0053] Throughout the specification, when a part is said to "comprising" (or including) a certain component, this does not mean that other components are excluded, but rather that other components can be included, unless specifically stated otherwise. In addition, terms such as "...part," "...unit," and "module" described in the specification mean a unit that processes at least one function or operation, which may be implemented by hardware, software, or a combination of hardware and software. In addition, the words "a" or "an," "one," "the," and similar related words may be used in the context of describing this specification (especially in the context of the claims below) to include both the singular and the plural, unless otherwise indicated herein or clearly contradicted by context.

[0054] The embodiments of this specification have been described with a focus on the data transmission and reception relationship between a base station and a mobile station. Here, the base station is understood as a terminal node of a network that directly communicates with the mobile station. Certain operations described herein as being performed by the base station may, in some cases, be performed by an upper node of the base station.

[0055] That is, in a network consisting of multiple network nodes including a base station, various operations performed for communication with a mobile station may be performed by the base station or other network nodes other than the base station. In this case, the term 'base station' may be replaced by terms such as fixed station, Node B, eNB (eNode B), gNB (gNode B), ng-eNB, advanced base station (ABS), or access point.

[0056] Additionally, in the embodiments of the present specification, the term terminal may be replaced with terms such as user equipment (UE), mobile station (MS), subscriber station (SS), mobile subscriber station (MSS), mobile terminal, or advanced mobile station (AMS).

[0057] Additionally, a transmitter refers to a fixed and / or mobile node that provides data or voice services, and a receiver refers to a fixed and / or mobile node that receives data or voice services. Therefore, for uplink, a mobile station can be the transmitter, and a base station can be the receiver. Similarly, for downlink, a mobile station can be the receiver, and a base station can be the transmitter.

[0058] Embodiments of the present specification may be supported by standard documents disclosed in at least one of wireless access systems, such as IEEE 802.xx system, 3rd Generation Partnership Project (3GPP) system, 3GPP Long Term Evolution (LTE) system, 3GPP 5G (5th generation) NR (New Radio) system and 3GPP2 system, and in particular, embodiments of the present specification may be supported by 3GPP TS (technical specification) 38.211, 3GPP TS 38.212, 3GPP TS 38.213, 3GPP TS 38.321 and 3GPP TS 38.331 documents.

[0059] Furthermore, the embodiments of this specification may be applied to other wireless access systems and are not limited to the aforementioned systems. For example, they may also be applicable to systems implemented after the 3GPP 5G NR system, and are not limited to a specific system.

[0060] That is, obvious steps or parts not described in the embodiments of this specification may be explained by reference to the above documents. In addition, all terms disclosed in this specification may be explained by the above standard documents.

[0061] Hereinafter, preferred embodiments according to the present specification will be described in detail with reference to the accompanying drawings. The detailed description set forth below, together with the accompanying drawings, is intended to illustrate exemplary embodiments of the present specification and is not intended to represent the only embodiments in which the technical components of the present specification may be implemented.

[0062] Additionally, specific terms used in the embodiments of this specification are provided to aid in understanding of this specification, and the use of these specific terms may be changed to other forms without departing from the technical spirit of this specification.

[0063] The following technology can be applied to various wireless access systems such as CDMA (code division multiple access), FDMA (frequency division multiple access), TDMA (time division multiple access), OFDMA (orthogonal frequency division multiple access), and SC-FDMA (single carrier frequency division multiple access).

[0064] In order to clarify the following description, the following description is based on a 3GPP communication system (e.g., LTE, NR, etc.), but the technical idea of ​​the present disclosure is not limited thereto. LTE may refer to technology after 3GPP TS 36.xxx Release 8. Specifically, LTE technology after 3GPP TS 36.xxx Release 10 may be referred to as LTE-A, and LTE technology after 3GPP TS 36.xxx Release 13 may be referred to as LTE-A pro. 3GPP NR may refer to technology after TS 38.xxx Release 15. 3GPP 6G may refer to technology after TS Release 17 and / or Release 18. “xxx” refers to a standard document detail number. LTE / NR / 6G may be collectively referred to as a 3GPP system.

[0065] For background information, terms, abbreviations, etc. used in this specification, reference may be made to standards documents published prior to the present disclosure. For example, reference may be made to the 36.xxx and 38.xxx standard documents.

[0066] In this specification, “A or B” can mean “only A,” “only B,” or “both A and B.” In other words, “A or B” in this specification can be interpreted as “A and / or B.” For example, “A, B or C” in this specification can mean “only A,” “only B,” “only C,” or “any combination of A, B, and C.”

[0067] As used herein, a slash ( / ) or a comma can mean "and / or." For example, "A / B" can mean "A and / or B." Accordingly, "A / B" can mean "only A," "only B," or "both A and B." For example, "A, B, C" can mean "A, B, or C."

[0068] In this specification, “at least one of A and B” may mean “only A,” “only B,” or “both A and B.” Additionally, in this specification, the expressions “at least one of A or B” or “at least one of A and / or B” may be interpreted identically to “at least one of A and B.”

[0069] Additionally, in this specification, “at least one of A, B and C” can mean “only A,” “only B,” “only C,” or “any combination of A, B and C.” Additionally, “at least one of A, B or C” or “at least one of A, B and / or C” can mean “at least one of A, B and C.”

[0070] Additionally, parentheses used herein may mean “for example.” Specifically, when indicated as “control information (PDCCH),” “PDCCH” may be proposed as an example of “control information.” In other words, “control information” in this specification is not limited to “PDCCH,” and “PDCCH” may be proposed as an example of “control information.” Furthermore, even when indicated as “control information (i.e., PDCCH),” “PDCCH” may be proposed as an example of “control information.”

[0071] Technical features individually described in a single drawing in this specification may be implemented individually or simultaneously.

[0072] Although not limited thereto, the various descriptions, functions, procedures, proposals, methods and / or operational flowcharts disclosed herein may be applied to various fields requiring wireless communication / connectivity (e.g., 5G) between devices.

[0073] Hereinafter, more specific examples will be provided with reference to the drawings. In the drawings / descriptions below, the same drawing reference numerals may represent identical or corresponding hardware blocks, software blocks, or functional blocks, unless otherwise described.

[0074] Figure 1 is a diagram illustrating an example of a communication system applied to this specification.

[0075] Referring to FIG. 1, a communication system (100) applied to the present specification includes a wireless device, a base station, and a network. Here, the wireless device refers to a device that performs communication using a wireless access technology (e.g., 5G NR, LTE) and may be referred to as a communication / wireless / 5G device. Although not limited thereto, the wireless device may include a robot (100a), a vehicle (100b-1, 100b-2), an XR (extended reality) device (100c), a hand-held device (100d), a home appliance (100e), an IoT (Internet of Things) device (100f), and an AI (artificial intelligence) device / server (100g). For example, the vehicle may include a vehicle equipped with a wireless communication function, an autonomous vehicle, a vehicle capable of performing vehicle-to-vehicle communication, etc. Here, the vehicles (100b-1, 100b-2) may include unmanned aerial vehicles (UAVs) (e.g., drones). The XR devices (100c) include augmented reality (AR) / virtual reality (VR) / mixed reality (MR) devices, and may be implemented in the form of head-mounted devices (HMDs), head-up displays (HUDs) installed in vehicles, televisions, smartphones, computers, wearable devices, home appliances, digital signage, vehicles, robots, etc. The portable devices (100d) may include smartphones, smart pads, wearable devices (e.g., smartwatches, smart glasses), computers (e.g., laptops, etc.), etc. The home appliances (100e) may include TVs, refrigerators, washing machines, etc. The IoT devices (100f) may include sensors, smart meters, etc. For example, the base station (120) and the network (130) may also be implemented as wireless devices, and a specific wireless device (120a) may act as a base station / network node to other wireless devices.

[0076] Wireless devices (100a to 100f) can be connected to a network (130) via a base station (120). AI technology can be applied to the wireless devices (100a to 100f), and the wireless devices (100a to 100f) can be connected to an AI server (100g) via a network (130). The network (130) can be configured using a 3G network, a 4G (e.g., LTE) network, a 5G (e.g., NR) network, etc. The wireless devices (100a to 100f) can communicate with each other via the base station (120) / network (130), but can also communicate directly (e.g., sidelink communication) without going through the base station (120) / network (130). For example, vehicles (100b-1, 100b-2) can communicate directly (e.g., V2V (vehicle to vehicle) / V2X (vehicle to everything) communication). In addition, IoT devices (100f) (e.g., sensors) can communicate directly with other IoT devices (e.g., sensors) or other wireless devices (100a to 100f).

[0077] Wireless communication / connection (150a, 150b, 150c) can be established between wireless devices (100a to 100f) / base stations (120), and base stations (120) / base stations (120). Here, the wireless communication / connection can be established through various wireless access technologies (e.g., 5G NR) such as uplink / downlink communication (150a), sidelink communication (150b) (or D2D communication), and base station-to-base station communication (150c) (e.g., relay, IAB (integrated access backhaul)). Through the wireless communication / connection (150a, 150b, 150c), the wireless device and base station / wireless device, and base stations and base stations can transmit / receive wireless signals to / from each other. For example, the wireless communication / connection (150a, 150b, 150c) can transmit / receive signals through various physical channels. To this end, at least some of the various configuration information setting processes for transmitting / receiving wireless signals, various signal processing processes (e.g., channel encoding / decoding, modulation / demodulation, resource mapping / demapping, etc.), and resource allocation processes may be performed based on various proposals of this specification.

[0078] FIG. 2 is a diagram illustrating an example of a wireless device applicable to this specification.

[0079] Referring to FIG. 2, the first wireless device (200a) and the second wireless device (200b) can transmit and receive wireless signals via various wireless access technologies (e.g., LTE, NR). Here, {the first wireless device (200a), the second wireless device (200b)} can correspond to {the wireless device (100x), the base station (120)} and / or {the wireless device (100x), the wireless device (100x)} of FIG. 1.

[0080] A first wireless device (200a) includes one or more processors (202a) and one or more memories (204a), and may further include one or more transceivers (206a) and / or one or more antennas (208a). The processor (202a) controls the memories (204a) and / or the transceivers (206a), and may be configured to implement the descriptions, functions, procedures, proposals, methods, and / or operational flowcharts disclosed herein. For example, the processor (202a) may process information in the memory (204a) to generate first information / signals, and then transmit a wireless signal including the first information / signals via the transceivers (206a). In addition, the processor (202a) may receive a wireless signal including second information / signals via the transceivers (206a), and then store information obtained from signal processing of the second information / signals in the memory (204a). The memory (204a) may be connected to the processor (202a) and may store various information related to the operation of the processor (202a). For example, the memory (204a) may perform some or all of the processes controlled by the processor (202a), or may store software code including instructions for performing the descriptions, functions, procedures, proposals, methods, and / or operational flowcharts disclosed herein. Here, the processor (202a) and the memory (204a) may be part of a communication modem / circuit / chip designed to implement wireless communication technology (e.g., LTE, NR). The transceiver (206a) may be connected to the processor (202a) and may transmit and / or receive wireless signals via one or more antennas (208a). The transceiver (206a) may include a transmitter and / or a receiver. The transceiver (206a) may be used interchangeably with an RF (radio frequency) unit. In this specification, wireless device may also mean a communication modem / circuit / chip.

[0081] One or more processors (202a) receive a first data block including a plurality of partial blocks, transmit first HARQ-ACK (Hybrid Automatic Repeat reQuest-Acknowledgement) information indicating the number of partial blocks in which errors occur among the partial blocks, receive a piggyback data block including at least one parity block and a second data block including new data, and transmit second HARQ-ACK information including information indicating whether the first data block was successfully recovered based on the piggyback data block and number information indicating the number of partial blocks in which errors occur among the partial blocks of the second data block.

[0082] The second wireless device (200b) includes one or more processors (202b), one or more memories (204b), and may further include one or more transceivers (206b) and / or one or more antennas (208b). The processor (202b) controls the memories (204b) and / or the transceivers (206b), and may be configured to implement the descriptions, functions, procedures, proposals, methods, and / or operational flowcharts disclosed herein. For example, the processor (202b) may process information in the memory (204b) to generate third information / signals, and then transmit a wireless signal including the third information / signals via the transceivers (206b). In addition, the processor (202b) may receive a wireless signal including fourth information / signals via the transceivers (206b), and then store information obtained from signal processing of the fourth information / signals in the memory (204b). The memory (204b) may be connected to the processor (202b) and may store various information related to the operation of the processor (202b). For example, the memory (204b) may perform some or all of the processes controlled by the processor (202b), or may store software code including instructions for performing the descriptions, functions, procedures, proposals, methods, and / or operational flowcharts disclosed herein. Here, the processor (202b) and the memory (204b) may be part of a communication modem / circuit / chip designed to implement wireless communication technology (e.g., LTE, NR). The transceiver (206b) may be connected to the processor (202b) and may transmit and / or receive wireless signals via one or more antennas (208b). The transceiver (206b) may include a transmitter and / or a receiver. The transceiver (206b) may be used interchangeably with an RF unit. In this specification, wireless device may also mean a communication modem / circuit / chip.

[0083] One or more processors (202b) transmit a first data block including a plurality of partial blocks, receive first HARQ-ACK (Hybrid Automatic Repeat reQuest-Acknowledgement) information indicating the number of partial blocks in which errors occur among the partial blocks, transmit a piggyback data block including at least one parity block and a second data block including new data, and receive second HARQ-ACK information including information indicating whether the first data block was successfully recovered based on the piggyback data block and number information indicating the number of partial blocks in which errors occur among the partial blocks of the second data block.

[0084] Hereinafter, hardware elements of the wireless device (200a, 200b) will be described in more detail. Although not limited thereto, one or more protocol layers may be implemented by one or more processors (202a, 202b). For example, one or more processors (202a, 202b) may implement one or more layers (e.g., functional layers such as physical (PHY), media access control (MAC), radio link control (RLC), packet data convergence protocol (PDCP), radio resource control (RRC), and service data adaptation protocol (SDAP)). One or more processors (202a, 202b) may generate one or more Protocol Data Units (PDUs) and / or one or more Service Data Units (SDUs) according to the descriptions, functions, procedures, proposals, methods, and / or operational flowcharts disclosed herein. One or more processors (202a, 202b) may generate messages, control information, data or information according to the descriptions, functions, procedures, proposals, methods and / or operational flowcharts disclosed herein. One or more processors (202a, 202b) may generate signals (e.g., baseband signals) including PDUs, SDUs, messages, control information, data or information according to the functions, procedures, proposals and / or methods disclosed herein and provide the signals to one or more transceivers (206a, 206b). One or more processors (202a, 202b) may receive signals (e.g., baseband signals) from one or more transceivers (206a, 206b) and obtain PDUs, SDUs, messages, control information, data or information according to the descriptions, functions, procedures, proposals, methods and / or operational flowcharts disclosed herein.

[0085] One or more processors (202a, 202b) may be referred to as a controller, a microcontroller, a microprocessor, or a microcomputer. One or more processors (202a, 202b) may be implemented by hardware, firmware, software, or a combination thereof. For example, one or more application specific integrated circuits (ASICs), one or more digital signal processors (DSPs), one or more digital signal processing devices (DSPDs), one or more programmable logic devices (PLDs), or one or more field programmable gate arrays (FPGAs) may be included in one or more processors (202a, 202b). The descriptions, functions, procedures, proposals, methods, and / or operational flowcharts disclosed herein may be implemented using firmware or software, and the firmware or software may be implemented to include modules, procedures, functions, etc. The descriptions, functions, procedures, suggestions, methods and / or operation flowcharts disclosed in this specification may be implemented using firmware or software configured to perform one or more processors (202a, 202b) or stored in one or more memories (204a, 204b) and executed by one or more processors (202a, 202b). The descriptions, functions, procedures, suggestions, methods and / or operation flowcharts disclosed in this specification may be implemented using firmware or software in the form of codes, instructions and / or sets of instructions.

[0086] One or more memories (204a, 204b) may be coupled to one or more processors (202a, 202b) and may store various forms of data, signals, messages, information, programs, codes, instructions, and / or commands. The one or more memories (204a, 204b) may be configured as read only memory (ROM), random access memory (RAM), erasable programmable read only memory (EPROM), flash memory, hard drives, registers, cache memory, computer readable storage media, and / or combinations thereof. The one or more memories (204a, 204b) may be located internally and / or externally to the one or more processors (202a, 202b). Additionally, the one or more memories (204a, 204b) may be coupled to the one or more processors (202a, 202b) via various technologies, such as wired or wireless connections.

[0087] One or more transceivers (206a, 206b) can transmit user data, control information, wireless signals / channels, etc., as mentioned in the methods and / or flowcharts of this specification, to one or more other devices. One or more transceivers (206a, 206b) can receive user data, control information, wireless signals / channels, etc., as mentioned in the descriptions, functions, procedures, proposals, methods and / or flowcharts of this specification, from one or more other devices. For example, one or more transceivers (206a, 206b) can be coupled to one or more processors (202a, 202b) and can transmit and receive wireless signals. For example, one or more processors (202a, 202b) can control one or more transceivers (206a, 206b) to transmit user data, control information, or wireless signals to one or more other devices. Additionally, one or more processors (202a, 202b) may control one or more transceivers (206a, 206b) to receive user data, control information, or wireless signals from one or more other devices. Additionally, one or more transceivers (206a, 206b) may be coupled to one or more antennas (208a, 208b), and one or more transceivers (206a, 206b) may be configured to transmit and receive user data, control information, wireless signals / channels, or the like, as referred to in the descriptions, functions, procedures, proposals, methods, and / or operational flowcharts disclosed herein, via one or more antennas (208a, 208b). In the present specification, one or more antennas may be multiple physical antennas or multiple logical antennas (e.g., antenna ports). One or more transceivers (206a, 206b) can convert received user data, control information, wireless signals / channels, etc. from RF band signals to baseband signals in order to process the received user data, control information, wireless signals / channels, etc. using one or more processors (202a, 202b).One or more transceivers (206a, 206b) may convert user data, control information, wireless signals / channels, etc. processed by one or more processors (202a, 202b) from baseband signals to RF band signals. For this purpose, one or more transceivers (206a, 206b) may include an (analog) oscillator and / or filter.

[0088] FIG. 3 is a diagram illustrating a method for processing a transmission signal applied to the present specification.

[0089] Referring to FIG. 3, the transmission signal may be processed by a signal processing circuit. At this time, the signal processing circuit (300) may include a scrambler (310), a modulator (320), a layer mapper (330), a precoder (340), a resource mapper (350), and a signal generator (360). At this time, as an example, the operations / functions of FIG. 3 may be performed in the processors (202a, 202b) and / or the transceivers (206a, 206b) of FIG. 2. In addition, as an example, the hardware elements of FIG. 3 may be implemented in the processors (202a, 202b) and / or the transceivers (206a, 206b) of FIG. 2. For example, blocks 310 to 350 may be implemented in the processor (202a, 202b) of FIG. 2, and block 360 may be implemented in the transceiver (206a, 206b) of FIG. 2, and are not limited to the above-described embodiments.

[0090] The codeword can be converted into a wireless signal through the signal processing circuit (300) of FIG. 3. Here, the codeword is an encoded bit sequence of an information block. The information block may include a transport block (e.g., a UL-SCH transport block, a DL-SCH transport block). The wireless signal may be transmitted through various physical channels (e.g., a PUSCH, a PDSCH) of FIG. 6. Specifically, the codeword can be converted into a bit sequence scrambled by a scrambler (310). The scramble sequence used for scrambling is generated based on an initialization value, and the initialization value may include ID information of the wireless device, etc. The scrambled bit sequence can be modulated into a modulation symbol sequence by a modulator (320). The modulation scheme may include pi / 2-binary phase shift keying (pi / 2-BPSK), m-phase shift keying (m-PSK), m-quadrature amplitude modulation (m-QAM), etc.

[0091] A complex modulation symbol sequence can be mapped to one or more transmission layers by a layer mapper (330). The modulation symbols of each transmission layer can be mapped to the corresponding antenna port(s) by a precoder (340) (precoding). The output z of the precoder (340) can be obtained by multiplying the output y of the layer mapper (330) by an N*M precoding matrix W. Here, N is the number of antenna ports, and M is the number of transmission layers. Here, the precoder (340) can perform precoding after performing transform precoding (e.g., discrete Fourier transform (DFT) transform) on the complex modulation symbols. In addition, the precoder (340) can perform precoding without performing transform precoding.

[0092] The resource mapper (350) can map modulation symbols of each antenna port to time-frequency resources. The time-frequency resources can include multiple symbols (e.g., CP-OFDMA symbols, DFT-s-OFDMA symbols) in the time domain and multiple subcarriers in the frequency domain. The signal generator (360) generates a wireless signal from the mapped modulation symbols, and the generated wireless signal can be transmitted to another device through each antenna. To this end, the signal generator (360) can include an inverse fast Fourier transform (IFFT) module, a cyclic prefix (CP) inserter, a digital-to-analog converter (DAC), a frequency uplink converter, and the like.

[0093] The signal processing process for receiving signals in a wireless device can be configured in reverse order of the signal processing process (310-360) of FIG. 3. For example, a wireless device (e.g., 200a, 200b of FIG. 2) can receive wireless signals from the outside through an antenna port / transceiver. The received wireless signals can be converted into baseband signals through a signal restorer. For this purpose, the signal restorer can include a frequency downlink converter, an analog-to-digital converter (ADC), a CP remover, and a fast Fourier transform (FFT) module. Thereafter, the baseband signal can be restored to a codeword through a resource demapper process, a postcoding process, a demodulation process, and a descrambling process. The codewords can be restored to the original information blocks through decoding. Accordingly, a signal processing circuit (not shown) for a received signal may include a signal restorer, a resource de-mapper, a postcoder, a demodulator, a de-scrambler, and a decoder.

[0094] FIG. 4 is a diagram illustrating another example of a wireless device to which the present specification applies.

[0095] Referring to FIG. 4, the wireless device (400) corresponds to the wireless devices (200a, 200b) of FIG. 2 and may be composed of various elements, components, units, and / or modules. For example, the wireless device (400) may include a communication unit (410), a control unit (420), a memory unit (430), and additional elements (440). The communication unit may include a communication circuit (412) and a transceiver(s) (414). For example, the communication circuit (412) may include one or more processors (202a, 202b) and / or one or more memories (204a, 204b) of FIG. 2. For example, the transceiver(s) (414) may include one or more transceivers (206a, 206b) and / or one or more antennas (208a, 208b) of FIG. 2. The control unit (420) is electrically connected to the communication unit (410), the memory unit (430), and the additional elements (440) and controls the overall operation of the wireless device. For example, the control unit (420) may control the electrical / mechanical operation of the wireless device based on the program / code / command / information stored in the memory unit (430). In addition, the control unit (420) may transmit information stored in the memory unit (430) to an external device (e.g., another communication device) via a wireless / wired interface through the communication unit (410), or store information received from an external device (e.g., another communication device) via a wireless / wired interface in the memory unit (430).

[0096] The additional element (440) may be configured in various ways depending on the type of the wireless device. For example, the additional element (440) may include at least one of a power unit / battery, an input / output unit, a driving unit, and a computing unit. Although not limited thereto, the wireless device (400) may be implemented in the form of a robot (Fig. 1, 100a), a vehicle (Fig. 1, 100b-1, 100b-2), an XR device (Fig. 1, 100c), a portable device (Fig. 1, 100d), a home appliance (Fig. 1, 100e), an IoT device (Fig. 1, 100f), a digital broadcasting terminal, a hologram device, a public safety device, an MTC device, a medical device, a fintech device (or a financial device), a security device, a climate / environmental device, an AI server / device (Fig. 1, 140), a base station (Fig. 1, 120), a network node, etc. Wireless devices may be mobile or stationary depending on the use / service.

[0097] In FIG. 4, various elements, components, units / parts, and / or modules within the wireless device (400) may be entirely interconnected via a wired interface, or at least some may be wirelessly connected via a communication unit (410). For example, within the wireless device (400), the control unit (420) and the communication unit (410) may be wired, and the control unit (420) and a first unit (e.g., 430, 440) may be wirelessly connected via the communication unit (410). In addition, each element, component, unit / part, and / or module within the wireless device (400) may further include one or more elements. For example, the control unit (420) may be composed of a set of one or more processors. For example, the control unit (420) may be composed of a set of a communication control processor, an application processor, an electronic control unit (ECU), a graphics processing processor, a memory control processor, etc. As another example, the memory unit (430) may be composed of RAM, DRAM (dynamic RAM), ROM, flash memory, volatile memory, non-volatile memory, and / or a combination thereof.

[0098] FIG. 5 is a drawing illustrating an example of a mobile device to which the present specification applies.

[0099] Figure 5 illustrates an example of a mobile device applicable to the present specification. The mobile device may include a smartphone, a smart pad, a wearable device (e.g., a smart watch, smart glasses), or a portable computer (e.g., a laptop, etc.). The mobile device may be referred to as a mobile station (MS), a user terminal (UT), a mobile subscriber station (MSS), a subscriber station (SS), an advanced mobile station (AMS), or a wireless terminal (WT).

[0100] Referring to FIG. 5, the portable device (500) may include an antenna unit (508), a communication unit (510), a control unit (520), a memory unit (530), a power supply unit (540a), an interface unit (540b), and an input / output unit (540c). The antenna unit (508) may be configured as a part of the communication unit (510). Blocks 510 to 530 / 540a to 540c correspond to blocks 410 to 430 / 440 of FIG. 4, respectively.

[0101] The communication unit (510) can transmit and receive signals (e.g., data, control signals, etc.) with other wireless devices and base stations. The control unit (520) can control components of the portable device (500) to perform various operations. The control unit (520) can include an AP (application processor). The memory unit (530) can store data / parameters / programs / codes / commands required for operating the portable device (500). In addition, the memory unit (530) can store input / output data / information, etc. The power supply unit (540a) supplies power to the portable device (500) and can include a wired / wireless charging circuit, a battery, etc. The interface unit (540b) can support connection between the portable device (500) and other external devices. The interface unit (540b) can include various ports (e.g., audio input / output ports, video input / output ports) for connection with external devices. The input / output unit (540c) can input or output video information / signals, audio information / signals, data, and / or information input from a user. The input / output unit (540c) may include a camera, a microphone, a user input unit, a display unit (540d), a speaker, and / or a haptic module.

[0102] For example, in the case of data communication, the input / output unit (540c) obtains information / signals (e.g., touch, text, voice, image, video) input by the user, and the obtained information / signals can be stored in the memory unit (530). The communication unit (510) can convert the information / signals stored in the memory into wireless signals, and transmit the converted wireless signals directly to other wireless devices or to a base station. In addition, the communication unit (510) can receive wireless signals from other wireless devices or base stations, and then restore the received wireless signals to the original information / signals. The restored information / signals can be stored in the memory unit (530) and then output in various forms (e.g., text, voice, image, video, haptic) through the input / output unit (540c).

[0103] In a wireless access system, a terminal can receive information from a base station via the downlink (DL) and transmit it to the base station via the uplink (UL). The information transmitted and received between the base station and the terminal includes general data and various control information, and various physical channels exist depending on the type and purpose of the information being transmitted and received.

[0104] Figure 6 illustrates physical channels and general signal transmission used in a wireless communication system.

[0105] Referring to Figure 6, in a wireless communication system, a terminal receives information from a base station via the downlink (DL), and the terminal transmits information to the base station via the uplink (UL). The information transmitted and received between the base station and the terminal includes data and various control information, and various physical channels exist depending on the type and purpose of the information they transmit and receive.

[0106] When a terminal is powered on or enters a new cell, it performs an initial cell search operation, such as synchronizing with the base station (S11). To this end, the terminal receives a Primary Synchronization Signal (PSS) and a Secondary Synchronization Signal (SSS) from the base station to synchronize with the base station and obtain information such as a cell ID. Afterwards, the terminal can receive a Physical Broadcast Channel (PBCH) from the base station to obtain broadcast information within the cell. Meanwhile, the terminal can receive a Downlink Reference Signal (DL RS) during the initial cell search phase to check the downlink channel status.

[0107] A terminal that has completed initial cell search can obtain more specific system information by receiving a physical downlink control channel (PDCCH) and a physical downlink shared channel (PDSCH) based on information contained in the PDCCH (S12).

[0108] Meanwhile, when accessing a base station for the first time or when there are no radio resources for signal transmission, the terminal may perform a random access procedure for the base station (S13 to S16). To this end, the terminal may transmit a specific sequence as a preamble through a physical random access channel (PRACH) (S13 and S15) and receive a response message (RAR (Random Access Response) message) to the preamble through a PDCCH and a corresponding PDSCH. In the case of a contention-based random access procedure, a contention resolution procedure may additionally be performed (S16).

[0109] The terminal that has performed the procedure described above can then perform PDCCH / PDSCH reception (S17) and physical uplink shared channel (PUSCH) / physical uplink control channel (PUCCH) transmission (S18) as general uplink / downlink signal transmission procedures. In particular, the terminal can receive downlink control information (DCI) through the PDCCH. Here, the DCI includes control information such as resource allocation information for the terminal, and different formats can be applied depending on the purpose of use.

[0110] Meanwhile, the control information that the terminal transmits to the base station via the uplink or that the terminal receives from the base station may include downlink / uplink ACK / NACK signals, CQI (Channel Quality Indicator), PMI (Precoding Matrix Index), RI (Rank Indicator), etc. The terminal may transmit the above-described control information such as CQI / PMI / RI via PUSCH and / or PUCCH.

[0111] <Structure of uplink and downlink channels>

[0112] 1. Downlink channel structure

[0113] The base station can transmit a related signal to the terminal through a downlink channel described below, and the terminal can receive a related signal from the base station through the downlink channel described below.

[0114] (1) Physical Downlink Shared Channel (PDSCH)

[0115] PDSCH carries downlink data (e.g., DL-shared channel transport block, DL-SCH TB) and applies modulation methods such as Quadrature Phase Shift Keying (QPSK), 16 Quadrature Amplitude Modulation (QAM), 64 QAM, and 256 QAM. A transport block (TB) is encoded to generate a codeword. PDSCH can carry multiple codewords. Scrambling and modulation mapping are performed for each codeword, and the modulation symbols generated from each codeword are mapped to one or more layers (Layer mapping). Each layer is mapped to resources along with a Demodulation Reference Signal (DMRS), generated as an OFDM symbol signal, and transmitted through the corresponding antenna port.

[0116] (2) Physical downlink control channel (PDCCH)

[0117] The PDCCH carries downlink control information (DCI) and employs modulation methods such as QPSK. A PDCCH consists of 1, 2, 4, 8, or 16 Control Channel Elements (CCEs), depending on the Aggregation Level (AL). Each CCE is comprised of six Resource Element Groups (REGs). Each REG is defined by one OFDM symbol and one (P)RB.

[0118] The terminal obtains DCI transmitted via the PDCCH by performing decoding (so-called blind decoding) on ​​a set of PDCCH candidates. The set of PDCCH candidates decoded by the terminal is defined as a PDCCH search space set. The search space set may be a common search space or a UE-specific search space. The terminal can obtain DCI by monitoring PDCCH candidates within one or more search space sets set by the MIB or upper layer signaling.

[0119] 2. Uplink channel structure

[0120] The terminal transmits a related signal to the base station through the uplink channel described below, and the base station receives the related signal from the terminal through the uplink channel described below.

[0121] (1) Physical Uplink Shared Channel (PUSCH)

[0122] PUSCH carries uplink data (e.g., UL-shared channel transport block, UL-SCH TB) and / or uplink control information (UCI), and is transmitted based on a CP-OFDM (Cyclic Prefix - Orthogonal Frequency Division Multiplexing) waveform, a DFT-s-OFDM (Discrete Fourier Transform - spread - Orthogonal Frequency Division Multiplexing) waveform, etc. When the PUSCH is transmitted based on a DFT-s-OFDM waveform, the UE transmits the PUSCH by applying transform precoding. For example, when transform precoding is disabled (e.g., transform precoding is disabled), the UE transmits the PUSCH based on the CP-OFDM waveform, and when transform precoding is enabled (e.g., transform precoding is enabled), the UE can transmit the PUSCH based on the CP-OFDM waveform or the DFT-s-OFDM waveform. PUSCH transmissions can be dynamically scheduled by UL grants in DCI, or semi-statically scheduled (configured grant) based on higher layer (e.g., RRC) signaling (and / or Layer 1 (L1) signaling (e.g., PDCCH)). PUSCH transmissions can be performed in a codebook-based or non-codebook-based manner.

[0123] (2) Physical Uplink Control Channel (PUCCH)

[0124] PUCCH carries uplink control information, HARQ-ACK and / or scheduling request (SR), and can be divided into multiple PUCCHs depending on the PUCCH transmission length.

[0125] Figure 7 is a diagram illustrating the structure of a wireless frame applicable to this specification.

[0126] Uplink and downlink transmissions based on the NR system can be based on frames such as those in FIG. 7. At this time, one radio frame has a length of 10 ms and can be defined as two 5 ms half-frames (HF). One half-frame can be defined as five 1 ms subframes (SF). One subframe is divided into one or more slots, and the number of slots within a subframe can depend on the subcarrier spacing (SCS). At this time, each slot can contain 12 or 14 OFDM (A) symbols depending on the cyclic prefix (CP). When a normal CP is used, each slot can contain 14 symbols. When an extended CP is used, each slot can contain 12 symbols. Here, the symbol may include an OFDM symbol (or CP-OFDM symbol), an SC-FDMA symbol (or DFT-s-OFDM symbol).

[0127] Table 1 shows the number of symbols per slot, the number of slots per frame, and the number of slots per subframe according to SCS when a general CP is used, and Table 2 shows the number of symbols per slot, the number of slots per frame, and the number of slots per subframe according to SCS when an extended CSP is used.

[0128] [Table 1]

[0129]

[0130] [Table 2]

[0131]

[0132] In Table 1 and Table 2 above, N slot symb represents the number of symbols in the slot, and N frame,μ slot represents the number of slots in the frame, and Nsubframe,μ slot can indicate the number of slots within a subframe.

[0133] Additionally, in a system to which the present specification is applicable, OFDM(A) numerology (e.g., SCS, CP length, etc.) may be set differently between multiple cells merged into a single terminal. Accordingly, the (absolute time) interval of a time resource (e.g., SF, slot, or TTI) (conveniently referred to as TU (time unit)) consisting of the same number of symbols may be set differently between the merged cells.

[0134] NR can support multiple numerologies (or subcarrier spacing (SCS)) to support various 5G services. For example, a 15 kHz SCS supports wide areas in traditional cellular bands; a 30 kHz / 60 kHz SCS supports dense urban areas, lower latency, and wider carrier bandwidth; and a 60 kHz or higher SCS can support bandwidths greater than 24.25 GHz to overcome phase noise.

[0135] The NR frequency band is defined by two types of frequency ranges (FR1, FR2). FR1 and FR2 can be configured as shown in Tables 3-1 and 3-2 below, for example. FR2 can also mean millimeter wave (mmW).

[0136] [Table 3-1]

[0137]

[0138] [Table 3-2]

[0139]

[0140] In addition, as an example, the numerology described above may be set differently in a communication system to which the present specification is applicable. For example, a terahertz wave (THz) band may be used as a frequency band higher than the FR2 described above. In the THz band, the SCS may be set larger than in the NR system, and the number of slots may also be set differently, and is not limited to the above-described embodiment. The THz band will be described later.

[0141] Figure 8 is a drawing illustrating a slot structure applicable to this specification.

[0142] A slot contains multiple symbols in the time domain. A carrier contains multiple subcarriers in the frequency domain. A Resource Block (RB) can be defined as multiple (e.g., 12) consecutive subcarriers in the frequency domain.

[0143] Additionally, a Bandwidth Part (BWP) is defined as multiple consecutive (P)RBs in the frequency domain, which can correspond to one numerology (e.g., SCS, CP length, etc.).

[0144] A carrier can contain up to N (e.g., 5) BWPs. Data communication is performed through an activated BWP, and only one BWP can be activated per terminal. Each element in the resource grid is referred to as a Resource Element (RE), to which a single complex symbol can be mapped.

[0145] 6G communication system

[0146] The 6G (wireless communication) system aims to achieve (i) very high data rates per device, (ii) a very large number of connected devices, (iii) global connectivity, (iv) very low latency, (v) low energy consumption for battery-free IoT devices, (vi) ultra-reliable connectivity, and (vii) connected intelligence with machine learning capabilities. The vision of the 6G system can be divided into four aspects: "intelligent connectivity," "deep connectivity," "holographic connectivity," and "ubiquitous connectivity," and the 6G system can satisfy the requirements as shown in Table 4 below. That is, Table 4 is a table showing an example of the requirements of the 6G system.

[0147] [Table 4]

[0148]

[0149] At this time, the 6G system may have key factors such as enhanced mobile broadband (eMBB), ultra-reliable low latency communications (URLLC), massive machine type communications (mMTC), AI integrated communication, tactile internet, high throughput, high network capacity, high energy efficiency, low backhaul and access network congestion, and enhanced data security.

[0150] FIG. 9 is a diagram illustrating an example of a communication structure that can be provided in a 6G system applicable to this specification.

[0151] Referring to Figure 9, 6G systems are expected to have 50 times higher simultaneous wireless communication connectivity than 5G wireless communication systems. URLLC, a key feature of 5G, is expected to become a more prominent technology in 6G communications by providing end-to-end latency of less than 1 ms. Furthermore, 6G systems will have significantly better volumetric spectral efficiency, unlike the commonly used area spectral efficiency. 6G systems can offer extremely long battery life and advanced battery technologies for energy harvesting, eliminating the need for separate charging for mobile devices in 6G systems. Furthermore, new network characteristics in 6G may include:

[0152] Satellite integrated network: 6G is expected to integrate with satellites to provide a global mobile network. The integration of terrestrial, satellite, and airborne networks into a single wireless communications system could be crucial for 6G.

[0153] Connected Intelligence: Unlike previous generations of wireless communication systems, 6G is revolutionary, upgrading the wireless evolution from "connected objects" to "connected intelligence." AI can be applied at every stage of the communication process (or at every signal processing step, as described below).

[0154] Seamless integration of wireless information and energy transfer: 6G wireless networks will transfer power to charge the batteries of devices such as smartphones and sensors. Therefore, wireless information and energy transfer (WIET) will be integrated.

[0155] Ubiquitous super 3-dimension connectivity: Access to networks and core network functions from drones and very low Earth orbit satellites will create super 3-dimension connectivity in 6G ubiquitous.

[0156] Some general requirements for the new network characteristics of 6G, such as the above, may be as follows:

[0157] Small cell networks: The concept of small cell networks was introduced to improve received signal quality in cellular systems by increasing throughput, energy efficiency, and spectral efficiency. Consequently, small cell networks are essential for 5G and beyond-5G (5GB) communication systems. Accordingly, 6G communication systems also adopt the characteristics of small cell networks.

[0158] Ultra-dense heterogeneous networks: Ultra-dense heterogeneous networks will be another key feature of 6G communication systems. Multi-tier networks comprised of heterogeneous networks improve overall QoS and reduce costs.

[0159] High-capacity backhaul: Backhaul connections are characterized by high-capacity backhaul networks to support high-volume traffic. High-speed fiber optics and free-space optics (FSO) systems may be potential solutions to this problem.

[0160] Radar Technology Integrated with Mobile Technology: High-precision localization (or location-based services) via communications is a key feature of 6G wireless communication systems. Therefore, radar systems will be integrated with 6G networks.

[0161] Softwarization and virtualization: Softwarization and virtualization are two critical features that underpin the design process in 5GB networks to ensure flexibility, reconfigurability, and programmability. Furthermore, billions of devices can be shared across a shared physical infrastructure.

[0162] <Key implementation technologies for 6G systems>

[0163] Artificial Intelligence (AI).

[0164] The most crucial and newly introduced technology for 6G systems is AI. 4G systems did not involve AI. 5G systems will support partial or very limited AI. However, 6G systems will fully support AI for automation. Advances in machine learning will create more intelligent networks for real-time communications in 6G. Incorporating AI into communications can streamline and improve real-time data transmission. AI can use numerous analyses to determine how complex target tasks should be performed. In other words, AI can increase efficiency and reduce processing delays.

[0165] Time-consuming tasks such as handover, network selection, and resource scheduling can be performed instantly using AI. AI can also play a crucial role in machine-to-machine (M2M), machine-to-human, and human-to-machine communications. Furthermore, AI can facilitate rapid communication in brain-computer interfaces (BCIs). AI-based communication systems can be supported by metamaterials, intelligent structures, intelligent networks, intelligent devices, intelligent cognitive radios, self-sustaining wireless networks, and machine learning.

[0166] Recent attempts to integrate AI into wireless communication systems have focused on the application layer and network layer, particularly deep learning in wireless resource management and allocation. However, this research is increasingly evolving to the MAC layer and physical layer, with attempts to combine deep learning with wireless transmission, particularly in the physical layer. AI-based physical layer transmission refers to applying AI-based signal processing and communication mechanisms, rather than traditional communication frameworks, in the fundamental signal processing and communication mechanisms. For example, this may include deep learning-based channel coding and decoding, deep learning-based signal estimation and detection, deep learning-based multiple input multiple output (MIMO) mechanisms, and AI-based resource scheduling and allocation.

[0167] Machine learning can be used for channel estimation and channel tracking, as well as for power allocation and interference cancellation at the physical layer of the downlink (DL). Machine learning can also be used for antenna selection, power control, and symbol detection in MIMO systems.

[0168] However, the application of DNN for transmission at the physical layer may have the following problems.

[0169] Deep learning-based AI algorithms require a large amount of training data to optimize training parameters. However, due to limitations in obtaining training data from specific channel environments, a large amount of training data is used offline. This means that static training on training data in specific channel environments can lead to conflicts with the dynamic characteristics and diversity of the wireless channel.

[0170] Furthermore, current deep learning primarily targets real-world signals. However, signals at the physical layer of wireless communications are complex signals. Further research is needed on neural networks capable of detecting complex domain signals to match the characteristics of wireless communication signals.

[0171] Below, we will look at machine learning in more detail.

[0172] Machine learning refers to a series of operations that train machines to perform tasks that humans can or cannot perform. Machine learning requires data and a learning model. In machine learning, data learning methods can be broadly categorized into three types: supervised learning, unsupervised learning, and reinforcement learning.

[0173] Neural network training aims to minimize output errors. It involves repeatedly inputting training data into a neural network, calculating the neural network output and target error for the training data, and backpropagating the neural network error from the output layer to the input layer to update the weights of each node in the neural network to reduce the error.

[0174] Supervised learning uses labeled training data, while unsupervised learning may not have labeled training data. For example, in the case of supervised learning for data classification, the training data may be data in which each training data category is labeled. Labeled training data is input to a neural network, and the error can be calculated by comparing the output (categories) of the neural network with the training data labels. The calculated error is backpropagated through the neural network in the backward direction (i.e., from the output layer to the input layer), and the connection weights of each node in each layer of the neural network can be updated according to the backpropagation. The amount of change in the connection weights of each updated node can be determined by the learning rate. The neural network's calculation of the input data and the backpropagation of the error can constitute a learning cycle (epoch). The learning rate can be applied differently depending on the number of iterations of the neural network's learning cycle. For example, in the early stages of training a neural network, a high learning rate can be used to quickly allow the network to reach a certain level of performance, thereby improving efficiency. In the later stages of training, a low learning rate can be used to improve accuracy.

[0175] Learning methods may vary depending on the characteristics of the data. For example, if the goal is to accurately predict data transmitted by a transmitter in a communication system, supervised learning is preferable to unsupervised learning or reinforcement learning.

[0176] The learning model corresponds to the human brain, and the most basic linear model can be thought of, but the machine learning paradigm that uses highly complex neural network structures, such as artificial neural networks, as learning models is called deep learning.

[0177] The neural network cores used in learning methods are mainly deep neural networks (DNN), convolutional deep neural networks (CNN), and recurrent Boltzmann machines (RNN), and these learning models can be applied.

[0178] An artificial neural network is an example of a network of multiple perceptrons.

[0179] Figure 10 shows an example of a perceptron structure.

[0180] Referring to Figure 10, the input vector x=(x1,x2,...,x d ) is entered, each component is weighted (W1,W2,...,W d ) and summing all the results, and then applying the activation function σ(·) to the entire process is called a perceptron. A large-scale artificial neural network structure can extend the simplified perceptron structure shown in Figure 10 to apply the input vector to different multi-dimensional perceptrons. For convenience of explanation, input values ​​or output values ​​are called nodes.

[0181] Meanwhile, the perceptron structure illustrated in Fig. 10 can be explained as consisting of a total of three layers based on input and output values. An artificial neural network in which there are H perceptrons of (d+1) dimensions between the 1st layer and the 2nd layer, and K perceptrons of (H+1) dimensions between the 2nd layer and the 3rd layer can be expressed as in Fig. 11.

[0182] Figure 11 shows an example of a multilayer perceptron structure.

[0183] Referring to Figure 11, the layer where the input vector is located is called the input layer, the layer where the final output value is located is called the output layer, and all layers located between the input layer and the output layer are called hidden layers. The example in Figure 11 discloses three layers, but when counting the number of actual artificial neural network layers, the input layer is excluded, so it can be viewed as a total of two layers. The artificial neural network is composed of two-dimensionally connected perceptrons of basic blocks.

[0184] The aforementioned input, hidden, and output layers can be applied jointly not only to multilayer perceptrons but also to various artificial neural network structures, such as CNNs and RNNs, which will be described later. The greater the number of hidden layers, the deeper the artificial neural network. The machine learning paradigm that uses sufficiently deep artificial neural networks as learning models is called deep learning. Furthermore, the artificial neural network used for deep learning is called a deep neural network (DNN).

[0185] Figure 12 illustrates a multilayer perceptron consisting of 8 hidden layers and 8 output layers.

[0186] The above multilayer perceptron structure is referred to as a fully connected neural network. A fully connected neural network has no connections between nodes in the same layer, but only between nodes in adjacent layers. DNNs, which have a fully connected neural network structure and are composed of multiple hidden layers and activation functions, can be effectively applied to identify correlation characteristics between inputs and outputs. Here, the correlation characteristic can refer to the joint probability of inputs and outputs.

[0187] Meanwhile, depending on how multiple perceptrons are connected to each other, various artificial neural network structures different from the aforementioned DNN can be formed.

[0188] Figure 13 shows an example of a convolutional neural network.

[0189] In a DNN, nodes within a single layer are arranged vertically in a one-dimensional space. However, Figure 13 assumes a two-dimensional arrangement of nodes, with w nodes in width and h nodes in height. In this case, a weight is assigned to each connection from an input node to the hidden layer, so a total of h×w weights must be considered.

[0190] The convolutional neural network of Fig. 13 has a problem in that the number of weights increases exponentially according to the number of connections. Therefore, instead of considering the connections of all modes between adjacent layers, it assumes that there are small filters, and performs weighted sum and activation function operations on the overlapping portions of the filters.

[0191] Each filter has a weight corresponding to the number of its size, and the weights can be learned so that a specific feature on the image can be extracted as a factor and output.

[0192] Figure 14 is a diagram showing an example of a filter operation in a convolutional neural network.

[0193] In Fig. 14, a 3×3 sized filter is applied to the 3×3 region at the top left of the input layer, and the output value of the weighted sum and activation function operation for the corresponding node is z 22 Save to .

[0194] The above filter performs weighted sum and activation function operations while moving at a certain horizontal and vertical interval while scanning the input layer, and places the output value at the current filter position. This operation method is similar to the convolution operation for images in the field of computer vision, so a deep neural network with this structure is called a convolutional neural network (CNN), and the hidden layer generated as a result of the convolution operation is called a convolutional layer. In addition, a neural network with multiple convolutional layers is called a deep convolutional neural network (DCNN).

[0195] In the convolutional layer, the number of weights can be reduced by calculating a weighted sum that includes only the nodes located in the area covered by the filter, starting from the node where the current filter is located. This allows a single filter to focus on features within a local area. Accordingly, CNNs can be effectively applied to image data processing where physical distance in a two-dimensional area is an important criterion for judgment. Meanwhile, CNNs can apply multiple filters immediately before the convolutional layer, and can generate multiple output results through the convolution operation of each filter.

[0196] Meanwhile, depending on the data properties, there may be data for which sequence characteristics are important. Considering the length variability and chronological relationship of such sequence data, a structure that applies a method of inputting one element of the data sequence at each timestep and inputting the output vector (hidden vector) of the hidden layer output at a specific timestep together with the immediately following element in the sequence is called a recurrent neural network structure.

[0197] Figure 15 shows an example of a neural network structure in which a recurrent loop exists.

[0198] Referring to Figure 15, a recurrent neural network (RNN) is a data sequence of an element (x1) at a certain time t. (t) , x2 (t) , ... ,x d (t) ) into a fully connected neural network, the previous time point t-1 is the hidden vector (z1 (t-1) , z2 (t-1) , ... ,z H (t-1) ) is input together and applies a weighted sum and activation function. The reason for transmitting the hidden vector to the next time point in this way is that the information in the input vector from the previous time points is considered to be accumulated in the hidden vector of the current time point.

[0199] Figure 16 shows an example of the operating structure of a recurrent neural network.

[0200] Referring to Figure 16, the recurrent neural network operates in a predetermined order of time for the input data sequence.

[0201] Input vector at time point 1 (x1 (t) , x2 (t) , ,..., x d (t) ) is input to the recurrent neural network, the hidden vector (z1) (1) ,z2 (1) ,...,z H (1) ) is the input vector (x1) at time point 2 (2) ,x2 (2) ,...,x d (2) ) is input with the vector (z1) of the hidden layer through the weighted sum and activation function. (2) ,z2 (2) ,...,z H (2) ) is determined. This process is repeated from time point 2, time point 3, ,,, until time point T.

[0202] Meanwhile, when multiple hidden layers are placed within a recurrent neural network, it is called a deep recurrent neural network (DRNN). Recurrent neural networks are designed to be useful for processing sequence data (e.g., natural language processing).

[0203] It is a neural network core used in a learning manner, and includes various deep learning techniques such as DNN, CNN, RNN, Restricted Boltzmann Machine (RBM), Deep Belief Network (DBN), and Deep Q-Network, and can be applied to fields such as computer vision, speech recognition, natural language processing, and speech / signal processing.

[0204] Recent attempts to integrate AI into wireless communication systems have focused on the application layer, network layer, and especially deep learning in wireless resource management and allocation. However, this research is increasingly evolving to the MAC layer and physical layer, with attempts to combine deep learning with wireless transmission, particularly at the physical layer. AI-based physical layer transmission refers to the application of AI-based signal processing and communication mechanisms, rather than traditional communication frameworks, in the fundamental signal processing and communication mechanisms. For example, this may include deep learning-based channel coding and decoding, deep learning-based signal estimation and detection, deep learning-based MIMO mechanisms, and AI-based resource scheduling and allocation.

[0205] <THz(Terahertz) 통신>

[0206] THz communications can be applied in 6G systems. For example, data transmission rates can be increased by increasing bandwidth. This can be achieved by using sub-THz communications with wide bandwidths and applying advanced massive MIMO technology.

[0207] Figure 17 is a diagram illustrating an electromagnetic spectrum applicable to this specification.

[0208] Referring to Figure 17, THz waves, also known as sub-millimeter waves, generally refer to a frequency band between 0.1 THz and 10 THz with corresponding wavelengths ranging from 0.03 mm to 3 mm. The 100 GHz to 300 GHz band (Sub-THz band) is considered a major portion of the THz band for cellular communications. Adding the Sub-THz band to the mmWave band will increase the capacity of 6G cellular communications. Among the defined THz bands, 300 GHz to 3 THz is in the far infrared (IR) frequency band. Although the 300 GHz to 3 THz band is part of the optical band, it is at the boundary of the optical band, immediately following the RF band. Therefore, this 300 GHz to 3 THz band exhibits similarities to RF.

[0209] Key characteristics of THz communications include (i) the widely available bandwidth to support very high data rates and (ii) the high path loss that occurs at high frequencies (requiring highly directional antennas). The narrow beamwidths generated by highly directional antennas reduce interference. The small wavelength of THz signals allows for a significantly larger number of antenna elements to be integrated into devices and base stations operating in this band. This enables the use of advanced adaptive array technologies to overcome range limitations.

[0210] Optical wireless technology

[0211] Optical wireless communication (OWC) technology is planned for 6G communications, in addition to RF-based communications for all possible device-to-access networks. These networks connect to network-to-backhaul / fronthaul networks. OWC technology has already been used in 4G communication systems, but it will be used more widely to meet the demands of 6G communication systems. OWC technologies such as light fidelity, visible light communication, optical camera communication, and wideband-based free space optical (FSO) communication are already well-known. Optical wireless communication can provide very high data rates, low latency, and secure communications. Light detection and ranging (LiDAR) can also be used for ultra-high-resolution 3D mapping in 6G communications based on wideband technology.

[0212] <FSO 백홀 네트워크>

[0213] The transmitter and receiver characteristics of an FSO system are similar to those of a fiber-optic network. Therefore, data transmission in an FSO system is similar to that of a fiber-optic system. Therefore, FSO can be a promising technology for providing backhaul connectivity in 6G systems, in conjunction with fiber-optic networks. Using FSO, ultra-long-distance communications are possible, even over distances exceeding 10,000 km. FSO supports high-capacity backhaul connectivity for remote and non-remote areas, such as the ocean, space, underwater, and isolated islands. FSO also supports cellular base station connections.

[0214] Massive MIMO Technology

[0215] One of the key technologies for improving spectral efficiency is the application of MIMO technology. As MIMO technology improves, spectral efficiency also improves. Therefore, massive MIMO technology will be crucial in 6G systems. Because MIMO technology utilizes multiple paths, multiplexing technology must be considered to ensure that data signals can be transmitted along more than one path, as well as beam generation and operation technologies suitable for the THz band.

[0216] Blockchain

[0217] Blockchain will become a crucial technology for managing massive amounts of data in future communication systems. Blockchain is a form of distributed ledger technology. A distributed ledger is a database distributed across numerous nodes or computing devices. Each node replicates and stores an identical copy of the ledger. Blockchains are managed by a peer-to-peer (P2P) network and can exist without being managed by a central authority or server. Data on a blockchain is collected and organized into blocks. Blocks are linked together and protected using cryptography. Blockchain perfectly complements large-scale IoT with its inherently enhanced interoperability, security, privacy, reliability, and scalability. Therefore, blockchain technology offers several features, such as interoperability between devices, traceability of large amounts of data, autonomous interaction with other IoT systems, and the massive connectivity stability of 6G communication systems.

[0218] 3D Networking

[0219] 6G systems integrate terrestrial and airborne networks to support vertically expanded user communications. 3D BS will be provided via low-orbit satellites and UAVs. Adding a new dimension in altitude and associated degrees of freedom, 3D connections differ significantly from existing 2D networks.

[0220] Quantum Communication

[0221] Unsupervised reinforcement learning holds promise in the context of 6G networks. Supervised learning approaches cannot label the massive amounts of data generated by 6G networks. Unsupervised learning does not require labeling. Therefore, this technology can be used to autonomously build representations of complex networks. Combining reinforcement learning and unsupervised learning allows for truly autonomous network operation.

[0222] Unmanned Aerial Vehicle

[0223] Unmanned aerial vehicles (UAVs), or drones, will be a key element in 6G wireless communications. In most cases, high-speed wireless connections will be provided using UAV technology. Base stations are installed on UAVs to provide cellular connectivity. UAVs offer specific capabilities not found in fixed base station infrastructure, such as easy deployment, robust line-of-sight links, and controlled mobility. During emergencies such as natural disasters, deploying terrestrial communications infrastructure is not economically feasible, and sometimes, volatile environments make it impossible to provide services. UAVs can easily handle these situations. UAVs will become a new paradigm in wireless communications. This technology facilitates three fundamental requirements for wireless networks: enhanced mobile broadband (eMBB), URLLC, and mMTC. UAVs can also support various purposes, such as enhancing network connectivity, fire detection, disaster emergency services, security and surveillance, pollution monitoring, parking monitoring, and accident monitoring. Therefore, UAV technology is recognized as one of the most important technologies for 6G communications.

[0224] Cell-free Communication

[0225] Tight integration of multiple frequencies and heterogeneous communication technologies is crucial in 6G systems. As a result, users will be able to seamlessly move from one network to another without requiring any manual configuration on their devices. The best network will be automatically selected from available communication technologies. This will break the limitations of the cell concept in wireless communications. Currently, user movement from one cell to another in dense networks results in excessive handovers, resulting in handover failures, handover delays, data loss, and a ping-pong effect. 6G cell-free communications will overcome all of these challenges and provide better QoS. Cell-free communications will be achieved through multi-connectivity and multi-tier hybrid technologies, as well as heterogeneous radios on devices.

[0226] <Wireless Information and Energy Transfer (WIET)>

[0227] WIET uses the same fields and waves as wireless communication systems. Specifically, sensors and smartphones will be charged using wireless power transfer during communication. WIET is a promising technology for extending the life of battery-powered wireless systems. Therefore, battery-less devices will be supported by 6G communications.

[0228] Integration of Sensing and Communication

[0229] Autonomous wireless networks are capable of continuously sensing dynamically changing environmental conditions and exchanging information between different nodes. In 6G, sensing will be tightly integrated with communications to support autonomous systems.

[0230] Integration of Access Backhaul Networks

[0231] In 6G, access network density can be extremely high. Each access network is connected to backhaul connections, such as fiber optics and FSO networks. To accommodate the large number of access networks, there will be tight integration between access and backhaul networks.

[0232] Holographic Beamforming

[0233] Beamforming is a signal processing procedure that adjusts an antenna array to transmit a wireless signal in a specific direction. It is a subset of smart antennas or advanced antenna systems. Beamforming technology offers several advantages, including high signal-to-noise ratio, interference avoidance and rejection, and high network efficiency. Holographic beamforming (HBF) is a novel beamforming method that differs significantly from MIMO systems because it uses software-defined antennas. HBF will be a highly effective approach for efficient and flexible signal transmission and reception in multi-antenna communication devices in 6G.

[0234] Big Data Analysis

[0235] Big data analytics is a complex process for analyzing diverse, large-scale data sets, or "big data." This process uncovers hidden data, unknown correlations, and customer trends, ensuring complete data management. Big data is collected from various sources, such as video, social networks, images, and sensors. This technology is widely used to process massive amounts of data in 6G systems.

[0236] <LIS(large intelligent surface)>

[0237] THz band signals have strong linearity, which can create many shadow areas due to obstacles. LIS technology, which enables expanded communication coverage, enhanced communication stability, and additional value-added services by installing LIS near these shadow areas, is becoming increasingly important. LIS is an artificial surface made of electromagnetic materials that can alter the propagation of incoming and outgoing radio waves. While LIS may be viewed as an extension of Massive MIMO, it differs from Massive MIMO in its array structure and operating mechanism. Furthermore, LIS operates as a reconfigurable reflector with passive elements, passively reflecting signals without using active RF chains, which offers the advantage of low power consumption. Furthermore, because each passive reflector in LIS must independently adjust the phase shift of the incoming signal, this can be advantageous for wireless communication channels. By appropriately adjusting the phase shift via the LIS controller, the reflected signal can be collected at the target receiver to boost the received signal power.

[0238] Terahertz (THz) wireless communication

[0239] Fig. 18 is a diagram illustrating a THz communication method applicable to this specification.

[0240] Referring to Fig. 18, THz wireless communication is a wireless communication using THz waves with a frequency of approximately 0.1 to 10 THz (1 THz = 1012 Hz), and may refer to terahertz (THz) band wireless communication using a very high carrier frequency of 100 GHz or higher. THz waves are located between the RF (Radio Frequency) / millimeter (mm) and infrared bands, and (i) compared to visible light / infrared rays, they penetrate non-metallic / non-polarizable materials well, and compared to RF / millimeter waves, they have a shorter wavelength, so they have high straightness and can focus beams.

[0241] In addition, since the photon energy of THz waves is only a few meV, it has the characteristic of being harmless to the human body. The frequency band expected to be used for THz wireless communication may be the D-band (110 GHz to 170 GHz) or H-band (220 GHz to 325 GHz) bands where propagation loss due to absorption of molecules in the air is small. In addition to 3GPP, standardization discussions for THz wireless communication are being centered around the IEEE 802.15 THz WG (working group), and standard documents issued by the IEEE 802.15 TG (task group) (e.g., TG3d, TG3e) may specify or supplement the contents described in this specification. THz wireless communication can be applied to wireless cognition, sensing, imaging, wireless communication, THz navigation, etc.

[0242] Specifically, referring to FIG. 18, THz wireless communication scenarios can be categorized into macro networks, micro networks, and nanoscale networks. In macro networks, THz wireless communication can be applied to vehicle-to-vehicle (V2V) connections and backhaul / fronthaul connections. In micro networks, THz wireless communication can be applied to fixed point-to-point or multi-point connections, such as wireless connections in indoor small cells and data centers, and near-field communication, such as kiosk downloading. Table 5 below shows examples of technologies that can be utilized in THz waves.

[0243] [Table 5]

[0244]

[0245] FIG. 19 is a diagram illustrating a THz wireless communication transceiver applicable to the present specification.

[0246] Referring to Figure 19, THz wireless communication can be classified based on the method for THz generation and reception. THz generation methods can be classified into optical or electronic device-based technologies.

[0247] Here, methods for generating THz using electronic components include a method using a semiconductor component such as a resonant tunneling diode (RTD), a method using a local oscillator and a multiplier, a MMIC (monolithic microwave integrated circuit) method using an integrated circuit based on a compound semiconductor HEMT (high electron mobility transistor), and a method using an Si-CMOS-based integrated circuit. In the case of Fig. 19, a multiplier (doubler, tripler, multiplier) is applied to increase the frequency, and it passes through a subharmonic mixer and is radiated by an antenna. Since the THz band forms a high frequency, a multiplier is essential. Here, the multiplier is a circuit that has an output frequency that is N times that of the input, and matches it to the desired harmonic frequency and filters out all remaining frequencies. In addition, beamforming can be implemented by applying an array antenna or the like to the antenna of Fig. 19. In Figure 19, IF represents intermediate frequency, tripler and multipler represent multipliers, PA represents a power amplifier, LNA represents a low noise amplifier, and PLL represents a phase-locked loop.

[0248] FIG. 20 is a diagram illustrating a THz signal generation method applicable to the present specification. FIG. 21 is a diagram illustrating a wireless communication transceiver applicable to the present specification.

[0249] Referring to FIGS. 20 and 21, optical device-based THz wireless communication technology refers to a method of generating and modulating a THz signal using an optical device. The optical device-based THz signal generation technology is a technology that generates an ultra-high-speed optical signal using a laser and an optical modulator, and converts it into a THz signal using an ultra-high-speed photodetector. Compared to a technology that uses only electronic devices, this technology makes it easy to increase the frequency, enables high-power signal generation, and obtains a flat response characteristic in a wide frequency band. In order to generate a THz signal based on an optical device, a laser diode, a wideband optical modulator, and an ultra-high-speed photodetector are required, as illustrated in FIG. 20. In the case of FIG. 20, the light signals of two lasers with different wavelengths are combined to generate a THz signal corresponding to the wavelength difference between the lasers. In Fig. 20, an optical coupler refers to a semiconductor device that transmits an electrical signal using optical waves to provide electrical isolation and coupling between circuits or systems, and a uni-travelling carrier photo-detector (UTC-PD) is a type of photodetector that uses electrons as active carriers and reduces the travel time of electrons by bandgap grading. The UTC-PD is capable of detecting light at 150 GHz or higher. In Fig. 20, an erbium-doped fiber amplifier (EDFA) represents an erbium-doped fiber amplifier, a photodetector (PD) represents a semiconductor device that can convert an optical signal into an electrical signal, an OSA represents an optical sub-assembly that modularizes various optical communication functions (e.g., photoelectric conversion, electro-optical conversion, etc.) into a single component, and a DSO represents a digital storage oscilloscope.

[0250] Fig. 22 is a diagram illustrating a transmitter structure applicable to the present specification. In addition, Fig. 23 is a diagram illustrating a modulator structure applicable to the present specification.

[0251] Referring to FIGS. 22 and 23, a signal phase, etc. can generally be changed by passing an optical source of a laser through an optical waveguide. At this time, data is loaded by changing the electrical characteristics through a microwave contact, etc. Therefore, the optical modulator output is formed as a modulated waveform. An optical / electrical converter (O / E converter) can generate a THz pulse according to an optical rectification operation by a nonlinear crystal, an optical / electrical conversion by a photoconductive antenna, an emission from a bunch of relativistic electrons, etc. A terahertz pulse (THz pulse) generated in the above manner can have a length in units of femtoseconds to picoseconds. An optical / electronic converter (O / E converter) performs down conversion by utilizing the non-linearity of the device.

[0252] Considering the THz spectrum usage, it is likely that multiple contiguous GHz bands will be used for THz systems, either fixed or mobile service. Based on the outdoor scenario, oxygen attenuation in the spectrum up to 1 THz is 10 2 The available bandwidth can be classified based on dB / km. Accordingly, a framework in which the available bandwidth is comprised of multiple band chunks can be considered. As an example of this framework, if the length of a terahertz pulse (THz pulse) for a single carrier is set to 50 ps, ​​the bandwidth (BW) becomes approximately 20 GHz.

[0253] Effective down-conversion from the infrared band to the terahertz band (THz band) depends on how to utilize the nonlinearity of the optical / electrical converter (O / E converter). In other words, to down-convert to the desired terahertz band (THz band), it is necessary to design an O / E converter with the most ideal non-linearity for transferring to the corresponding terahertz band (THz band). If an O / E converter that is not suitable for the target frequency band is used, errors are likely to occur in the amplitude and phase of the corresponding pulse.

[0254] In a single-carrier system, a terahertz transmission and reception system can be implemented using a single optical-to-electrical converter. Depending on the channel environment, in a multi-carrier system, the number of optical-to-electrical converters may be equal to the number of carriers. This phenomenon will be particularly noticeable in a multi-carrier system that utilizes multiple broadbands according to the aforementioned spectrum usage plan. In this regard, a frame structure for the multi-carrier system may be considered. A signal down-converted using an optical-to-electrical converter may be transmitted in a specific resource region (e.g., a specific frame). The frequency domain of the specific resource region may include a plurality of chunks. Each chunk may be composed of at least one component carrier (CC).

[0255] Here, the wireless communication technology implemented in the wireless devices (200a, 200b) of the present specification may include not only LTE, NR, and 6G, but also Narrowband Internet of Things for low-power communication. At this time, for example, NB-IoT technology may be an example of LPWAN (Low Power Wide Area Network) technology, and may be implemented with standards such as LTE Cat NB1 and / or LTE Cat NB2, and is not limited to the above-described names. Additionally or alternatively, the wireless communication technology implemented in the wireless devices (XXX, YYY) of the present specification may perform communication based on LTE-M technology. At this time, for example, LTE-M technology may be an example of LPWAN technology, and may be called by various names such as eMTC (enhanced Machine Type Communication). For example, LTE-M technology can be implemented by at least one of various standards such as 1) LTE CAT 0, 2) LTE Cat M1, 3) LTE Cat M2, 4) LTE non-BL (non-Bandwidth Limited), 5) LTE-MTC, 6) LTE Machine Type Communication, and / or 7) LTE M, and is not limited to the above-described names. Additionally or alternatively, the wireless communication technology implemented in the wireless device (200a, 200b) of the present specification can include at least one of ZigBee, Bluetooth, and Low Power Wide Area Network (LPWAN) considering low-power communication, and is not limited to the above-described names. For example, ZigBee technology can create personal area networks (PAN) related to small / low-power digital communication based on various standards such as IEEE 802.15.4, and can be called by various names.

[0256] Figure 24 illustrates an example of a wireless interface user plane protocol stack between a terminal and a base station (BS). Referring to Figure 24, the user plane protocol stack can be divided into Layer 1 (i.e., the PHY layer) and Layer 2. The user plane refers to the path through which data generated at the application layer, such as voice data or Internet packet data, is transmitted.

[0257] Figure 25 illustrates an example of a radio interface control plane protocol stack between a terminal and a base station (BS). The control plane refers to a path along which control messages used by the terminal and the network to manage calls are transmitted. Referring to Figure 25, the control plane protocol stack can be divided into Layer 1 (i.e., PHY layer), Layer 2, Layer 3 (e.g., RRC layer), and NAS (Non-Access Stratum) layers. Layers 1, 2, and 3 are referred to as AS (Access Stratum).

[0258] In the 3GPP LTE system, Layer 2 is divided into the sublayers of MAC, RLC, and PDCP. In the 3GPP NR system, Layer 2 is divided into the sublayers of MAC, RLC, PDCP, and SDAP. The PHY layer provides transport channels to the MAC sublayer, which in turn provides logical channels to the RLC sublayer, which in turn provides RLC channels to the PDCP sublayer, and which in turn provides radio bearers to the SDAP sublayer. The SDAP sublayer provides Quality of Service (QoS) flows to the 5G core network.

[0259] The main services and functions of the MAC sublayer in the 3GPP NR system include: mapping between logical channels and transport channels; multiplexing / demultiplexing MAC SDUs belonging to one or different logical channels to / from transport blocks (TBs) delivered to / from the physical layer on the transport channel; reporting of scheduling information; error correction through Hybrid Automatic Repeat Request (HARQ) (one HARQ entity per cell in case of Carrier Aggregation (CA)); priority handling between terminals by dynamic scheduling; priority handling between logical channels of a single terminal by logical channel prioritization; and padding. A single MAC entity can support multiple numerologies, transmission timings, and cells. Mapping restrictions in logical channel prioritization control the numerologies, cells, and transmission timings that a logical channel can use.

[0260] MAC provides various types of data transmission services. To accommodate these different types of data transmission services, several types of logical channels are defined. That is, each logical channel supports a specific type of information transmission. Each logical channel type is defined based on the type of information being transmitted. Logical channels are classified into two groups: control channels and traffic channels. Control channels are used exclusively for the transmission of control plane information, while traffic channels are used exclusively for the transmission of user plane information. The Broadcast Control Channel (BCCH) is a downlink logical channel for broadcasting system control information. The Paging Control Channel (PCCH) is a downlink logical channel for transmitting paging information, system information change notifications, and indications of ongoing Public Warning Service (PWS) broadcasts. The Common Control Channel (CCCH) is a logical channel for transmitting control information between a terminal and the network and is used for terminals without an RRC connection to the network. The Dedicated Control Channel (DCCH) is a point-to-point bidirectional logical channel for transmitting dedicated control information between the terminal and the network and is used by terminals with an RRC connection. Dedicated Traffic Channel (DTCH) is a point-to-point logical channel dedicated to a single terminal for transmitting user information. DTCH can exist in both uplink and downlink. In downlink, the following connections exist between logical channels and transport channels: BCCH can be mapped to BCH (Broadcast Channel), BCCH can be mapped to DL-SCH (Downlink Shared Channel), PCCH can be mapped to PCH (Paging Channel), CCCH can be mapped to DL-SCH, DCCH can be mapped to DL-SCH, and DTCH can be mapped to DL-SCH. In uplink, the following connections exist between logical channels and transport channels:CCCH can be mapped to UL-SCH (Uplink Shared Channel), DCCH can be mapped to UL-SCH, and DTCH can be mapped to UL-SCH.

[0261] The RLC sublayer supports three transmission modes: Transparent Mode (TM), Unacknowledged Mode (UM), and Acknowledged Mode (AM). RLC establishment is per logical channel, independent of numerology and / or transmission duration. The main services and functions of the RLC sublayer in 3GPP NR systems depend on the transmission mode and include: transmission of upper layer PDUs; sequence number assignment independent of that in PDCP (UM and AM); error correction via ARQ (AM only); segmentation (AM and UM) and re-segmentation (AM only) of RLC SDUs; reassembly of SDUs (AM and UM); duplicate detection (AM only); RLC SDU discard (AM and UM); RLC re-establishment; and protocol error detection (AM only).

[0262] In a 3GPP NR system, the main services and functions of the PDCP sublayer for the user plane include sequence numbering; header compression and decompression using Robust Header Compression (ROHC); user data transmission; reordering and duplicate detection; in-order delivery; PDCP PDU routing (in case of split bearer); retransmission of PDCP SDUs; ciphering, decryption, and integrity protection; PDCP SDU discard; PDCP re-establishment and data recovery for the RLC AM; PDCP status reporting for the RLC AM; replication of PDCP PDUs and indication of discarding replication to lower layers. The main services and functions of the PDCP sublayer for the control plane include sequence numbering; ciphering, decryption, and integrity protection; control plane data transmission; reordering and duplicate detection; in-order delivery; replication of PDCP PDUs and indication of discarding replication to lower layers.

[0263] Key services and functions of SDAP in 3GPP NR systems include mapping between QoS flows and data radio bearers; and indicating QoS Flow IDs (QFIs) on both DL and UL packets. A single protocol entity in SDAP is established for each individual PDU session.

[0264] In a 3GPP NR system, the main services and functions of the RRC sublayer include: broadcasting of system information related to AS and NAS; paging initiated by 5GC or NG-RAN; establishment, maintenance, and release of RRC connection between UE and NG-RAN; security functions including key management; establishment, configuration, maintenance, and release of signaling radio bearer (SRB) and data radio bearer (DRB); mobility functions (including handover and context transfer, UE cell selection and reselection and control of cell selection and reselection, and inter-RAT mobility); QoS management functions; UE measurement reporting and report control; detection and recovery of radio link failure; and transmission of NAS messages from / to UE to / from NAS.

[0265] The above-mentioned contents can be applied in combination with the embodiments proposed in this specification, which will be described later, or can be supplemented to clarify the technical features of the embodiments proposed in this specification. The embodiments described below are distinguished merely for convenience of explanation, and it is obvious that some components of one embodiment can be substituted for some components of another embodiment, or can be applied in combination with each other. The present disclosure relates to a wireless transmission device, method, and procedure for transmitting large amounts of data with low latency in a wireless communication system.

[0266] As the transmission speed of wireless communication systems increases, the size of data blocks transmitted by devices (e.g., transport blocks (TB), hereinafter referred to as TB for convenience) is also increasing. Accordingly, techniques have been developed to divide a single data block (e.g., TB) into multiple sub-blocks (e.g., code blocks (CB), hereinafter referred to as CB) and transmit them.

[0267] The transmitter attaches a CRC to each code block as well as the entire transmission block and transmits it, and the receiver can check the CRC for each code block. If retransmission is required, the receiver can reduce processing time and power consumption by re-decoding only the code blocks where transmission errors occurred. For example, in wireless communication systems, 5G NR has introduced a technique where multiple code blocks are grouped together to create a Code Block Group (CBG), and when the receiver requests retransmission for each code block group, the transmitter retransmits only the requested code block group.

[0268] If there is no feedback channel to request retransmission or retransmission is not feasible, an erasure code may be used.

[0269] An erasure code may be a code that transforms an original message consisting of k symbols into a longer message consisting of n symbols, such that the original message can be recovered from a subset of the n symbols. Here, r = k / n may be referred to as the code rate.

[0270] Erasure codes can be used alone, but they can also be used in conjunction with Low-Density Parity-Check (LDPC) codes or Turbo codes to improve the error floor or reduce transmission delay due to Automatic Repeat ReQuest (ARQ).

[0271] For example, wireless communication systems like 5G NR have been standardized to support three key scenarios: enhanced Mobile Broadband (eMBB), massive Machine Type Communication (mMTC), and Ultra-Reliable Low-Latency Communication (URLLC) to support diverse vertical services. Because these scenarios are not mutually exclusive, a single system or base station can support them simultaneously.

[0272] In 5G NR downlink, eMBB traffic is typically scheduled in slot units, but URLLC traffic, which requires shorter transmission delay, can be scheduled in units smaller than slots to reduce transmission delay.

[0273] Therefore, URLLC data transmission may be scheduled while eMBB data is being transmitted. At this time, all radio resources may be used for eMBB transmission, resulting in a shortage of radio resources for URLLC transmission. In this case, the base station may puncture some eMBB radio resources and use them for URLLC transmission. In this way, some of the eMBB data or parity information may not be transmitted due to radio resource preemption for URLLC transmission, which may increase the probability of decoding failure at the terminal. Transmission errors of eMBB data caused by preemption of URLLC traffic can be recovered through HARQ-ACK (Hybrid Automatic Repeat reQuest Acknowledgement) feedback and retransmission, but this may lead to a decrease in the transmission speed and an increase in transmission delay of the eMBB traffic.

[0274] The symbols / abbreviations / terms used in this specification are as follows.

[0275] ACK: Acknowledgement

[0276] ARQ: Automatic Repeat reQuest

[0277] CB: Code Block

[0278] CBS: Code Block Size

[0279] CE: Control Element

[0280] CRC: Cyclic Redundancy Check

[0281] DCB: Data Code Block

[0282] DCI: Downlink Control Information

[0283] eMBB: Enhanced Mobile Broad-Band

[0284] HARQ: Hybrid Automatic Repeat reQuest

[0285] HARQ-ACK: Hybrid Automatic Repeat request Acknowledgement

[0286] L: Length

[0287] MAC: Medium Access Control

[0288] mMTC: Massive Machine Type Communication

[0289] NACK: Negative Acknowledgement

[0290] NR: New Radio

[0291] PCB: Parity Code Block

[0292] PDCCH: Physical Downlink Control Channel

[0293] PDSCH: Physical Downlink Shared Channel

[0294] PN: Process Number

[0295] PUCCH: Physical Uplink Control Channel

[0296] PUSCH: Physical Uplink Shared Channel

[0297] RRC: Radio Resource Control

[0298] TB: Transport Block

[0299] TBS: Transport Block Size

[0300] URLLC: Ultra-Reliable Low-Latency Communication

[0301] The present disclosure relates to a retransmission device, method and procedure for recovering from a transmission error when a transmission error occurs or is expected to occur in a wireless communication system.

[0302] Below, a retransmission and HARQ-ACK (Hybrid Automatic Repeat reQuest Acknowledgement) feedback device, method, and procedure capable of efficiently recovering transmission errors occurring in a wireless communication system are described.

[0303] To recover from errors that occur during transmission, the transmitter can perform retransmissions. Retransmissions may use fewer radio resources than the initial transmission. CBG-based retransmissions can further reduce the amount of radio resources required, as only the portion of the CBG that experienced errors is retransmitted.

[0304] In wireless transmission systems using HARQ, transmission and retransmission procedures are managed per HARQ process. This means that once a new data transmission is initiated with a single HARQ process, the transmission and retransmission procedures are exhausted until all data has been successfully transmitted or until a decision is made to discard failed data. Consequently, even if sufficient radio resources exist, excluding those required for retransmission, new data cannot be transmitted. This can result in reduced transmission speeds and increased transmission delays. This problem can be exacerbated in TDD systems, where the downlink and uplink are temporally separated.

[0305] The present disclosure describes a wireless transmission device, method and procedure capable of increasing a transmission speed and reducing a transmission delay by transmitting new data and data or parity information of a first transport block (TB) in which a transmission error has occurred (or in which a transmission error is expected to occur) together through a new transport block (second transport block).

[0306] The present disclosure focuses on a systematic erasure code. However, the contents of the present disclosure are not limited to systematic erasure codes, and can also be applied to systematic forward error correction (FEC) codes other than erasure codes. In addition, the present disclosure focuses on an optimal erasure code that requires k error-free data and parity symbols to recover k data symbols including erroneous symbols. However, the present disclosure can also be applied to sub-optimal / near-optimal erasure codes that require k or slightly more (n) error-free data and parity symbols, such as Raptor codes, or forward error correction codes that require a certain level of data and parity symbols or more depending on the signal-to-noise ratio (SNR), etc.

[0307] This disclosure focuses on downlink. However, the contents of this disclosure are not limited to downlink and can also be applied to uplink, sidelink, etc.

[0308] In wireless communication systems such as LTE and NR, a transmitter divides a transport block (TB) into multiple data code blocks (DCBs) (code block segmentation), and performs encoding on each DCB using an LDPC code, turbo code, or polar code to transmit the data along with parity bits.

[0309] The receiver decodes each DCB individually, and if all DCBs are decoded without error, it can assemble the DCBs (code block assembly) to restore the transmitted TB. If any DCB fails to be decoded, the receiver can request retransmission from the transmitter. When the transmitter retransmits, if it can transmit redundancy, such as parity information necessary to recover from errors, along with the new data, it can increase transmission speed and reduce transmission delay.

[0310] Figures 26 and 27 illustrate feedback from a terminal and transmission from a base station in the downlink.

[0311] Referring to FIGS. 26 and 27, the terminal can feed back the number of DCBs in which errors occurred to the base station, and the base station can perform external erasure encoding between the DCBs to generate as many parity code blocks (PCBs) as the terminal needs to recover from the errors and transmit them together with new data.

[0312] More specifically, in the example of FIG. 26, the base station can add a CRC to transport block 1 (TB 1) including MAC PDU 1 and divide it into multiple DCBs, i.e., DCBs 1-1 to 1-15, and transmit them. Each DCB can be transmitted through channel encoding such as LDPC coding, Turbo coding, or Polar coding.

[0313] The terminal can perform channel decoding on each received DCB, i.e., DCBs 1-1 through 1-15. At this time, there may be DCBs that fail to decode due to unrecovered errors. Figure 26 illustrates a case where errors in DCBs 1-5 and 1-13 are not recovered. The terminal can feedback the number of DCBs with errors to the base station as a HARQ-ACK. If the number of DCBs with errors is 0, it can be considered an ACK, otherwise it can be considered a NACK.

[0314] Referring to FIG. 27, a base station that receives HARQ-ACK feedback can perform erasure encoding on DCBs before channel coding is performed, i.e., DCBs 1-1 to 1-15, to generate a sufficient number of parity code blocks (PCBs) for the terminal to recover from errors. In the case of an optimal erasure code, the number of PCBs sufficient for the terminal to recover from errors may be equal to the number of DCBs in which errors occurred. In the case of a near-optimal erasure code, the number of PCBs sufficient for the terminal to recover from errors may be equal to or greater than the number of DCBs in which errors occurred. In the example of FIG. 27, in the case of an optimal erasure code, the transmitter can generate PCBs 1-1 and 1-2.

[0315] A base station can generate piggyback transport blocks (PTBs, also referred to as piggyback transport blocks) from PCBs. A PTB can consist of a PTB size (PTBS), a PTB header containing information related to one or more PCBs, and one or more PCBs. The base station can add a cyclic redundancy check (CRC) (also referred to as a PTB CRC) to the PTB (or the PTB can include a PTB CRC).

[0316] The base station can generate a new transport block 2 (TB 2) that includes the PTB, the PTB CRC, and new data (e.g., MAC PDU 2). If there is no new data (MAC PDU) to transmit, the base station can generate TB 2 with only the PTB and omit the PTB CRC. The base station can add the CRC to TB 2, divide it into multiple DCBs, i.e., DCBs 2-1 to 2-10, and transmit each DCB by performing channel encoding on it. The size of the DCBs generated from TB 2 (i.e., DCBs 2-1 to 2-10) (let's call this CBS2) may not be the same as the sizes of the DCBs generated from TB 1 (i.e., DCBs 1-1 to 1-15) and PCBs (i.e., PCBs 1-1 and 1-2) (let's call this CBS1).

[0317] The terminal can perform channel decoding on each of the received DCBs, i.e., DCBs 2-1 to 2-10. If all DCBs are decoded without error, the terminal can combine the DCBs to obtain the PTB and MAC PDU 2. The terminal can obtain the PTB even if the DCBs including the PTB and PTB CRC are decoded without error and errors occur in the remaining DCBs.

[0318] The terminal can obtain PCBs required to restore DCBs 1-5 and 1-13 of TB 1, i.e., PCBs 1-1 and 1-2, from the acquired PTB. The terminal can restore DCBs 1-5 and 1-13 by performing erasure decoding with DCBs 1-1 to 1-4, 1-6 to 1-12, and 1-14 to 1-15 decoded without error in the initial transmission of TB 1, i.e., PDSCH 1, and PCBs 1-1 and 1-2 acquired from the PTB of TB 2. The terminal can obtain TB 1 and MAC PDU 1 by combining all DCBs from DCBs 1-1 to 1-15, including the restored DCBs.

[0319] The base station can inform the terminal whether or not to transmit the PTB through the PTB Indicator (PTBI) included in the DCI. In the examples of FIGS. 26 and 27, the PTBI value of DCI 1, which carries scheduling information for TB 1 and PDSCH 1 that does not include the PTB, can be set to 0 to indicate that the PTB is not transmitted. The PTBI value of DCI 2, which carries scheduling information for TB 2 and PDSCH 2 that includes the PTB, can be set to 1 to indicate that the PTB is transmitted. The terminal can determine whether or not to transmit the PTB through the PTBI included in the DCI and perform the PTB acquisition procedure.

[0320] The base station can enable the terminal to easily obtain the PTB size and PTB header by transmitting the PTB at the very beginning of the TB. In this case, the terminal can obtain information such as the PTB size, PTB header, PTB CRC location, and the size of the MAC PDU transmitted together by decoding only the first DCB without error. In other words, the terminal can easily obtain this information by ensuring that the PTB size and PTB header are always transmitted in a designated location within the first DCB.

[0321] Depending on the embodiment, the base station may transmit the PTB at the end of the TB. In this case, the base station may transmit the size of the PTB at the end.

[0322] Depending on the embodiment, the size information of the PTB (piggyback data block) may be located a certain offset after the start of the second data block (TB 2), or a certain offset before the end of the second data block. The offset may have a value greater than or equal to 0. The offset may be a predetermined value or a value set by the network.

[0323] Figures 28 and 29 are other examples of feedback from a terminal and transmission from a base station in the downlink.

[0324] Referring to FIGS. 28 and 29, a portion of the radio resources of PDSCH 1, on which TB 1 is transmitted, may be preempted by URLLC data transmission. This allows transmission delay to be reduced by transmitting DCBs, on which part of the data and / or parity information is not transmitted, to the PTB included in the new TB 2 before receiving the HARQ-ACK from the terminal.

[0325] More specifically, in the example of FIG. 28, the base station can add a CRC to TB 1 including MAC PDU 1 and transmit it by dividing it into multiple DCBs, i.e., DCBs 1-1 to 1-15. Each DCB can be transmitted through channel encoding such as LDPC coding, Turbo coding, or Polar coding.

[0326] While transmitting PDSCH 1, there may be a case where URLLC data transmission is required. In this case, the base station may use some of the radio resources of PDSCH 1 to transmit URLLC data. That is, data or parity information generated from the URLLC TB may be transmitted without transmitting some of the data or parity information of TB 1. Figure 28 illustrates a case where some of DCBs 1-8 and DCBs 1-9 are preempted by the URLLC TB.

[0327] The terminal can perform channel decoding on each of the received DCBs, i.e., DCBs 1-1 through 1-15. At this time, decoding failure may occur in DCBs 1-8 and 1-9, where some data and / or parity information is punctured and not transmitted. Even among DCBs not preempted by the URLLC TB, decoding failure may occur due to transmission errors caused by fading, interference, or noise of the wireless channel, such as DCBs 1-13.

[0328] As in the example of Fig. 28, if a portion of TB 1 is preempted by a URLLC TB, which is likely to cause transmission errors, the base station can reduce transmission delay by transmitting DCBs, in which some data and / or parity information is not transmitted due to URLLC TB preemption, to the PTB of TB 2 before receiving a HARQ-ACK from the terminal. Additionally, PCBs capable of recovering errors caused by channel influences other than preemption by the URLLC TB can be transmitted to the PTB of TB 2.

[0329] Referring to FIG. 29, a base station can generate a PTB with one or more PCBs that can be used to recover transmission errors of one or more DCBs preempted by a URLLC TB and other DCBs. The base station can generate a PCB, i.e., PCB 1-1, that can be used by a terminal to recover DCB errors by performing erasure encoding on DCBs 1-1 to 1-15. The base station can generate a PTB with a PCB, i.e., PCB 1-1, that can be used to recover transmission errors of DCBs preempted by a URLLC TB, i.e., DCBs 1-8 and 1-9, and other DCBs. A PTB can be composed of a PTB header that includes information related to the size of the PTB, one or more DCBs and zero or more PCBs, and one or more DCBs and zero or more PCBs. If a PTB includes zero PCBs, only one or more DCBs can be included in the PTB (i.e., depending on the embodiment, only a DCB among a DCB and a PCB may be retransmitted through the PTB). The base station can add a CRC to the PTB.

[0330] The base station can generate a new TB 2 with the PTB, PTB CRC, and new data (e.g., MAC PDU 2). If there is no new data to transmit (e.g., MAC PDU), the base station can generate TB 2 with only the PTB and omit the PTB CRC. The base station can add a CRC to TB 2, divide it into multiple DCBs, i.e., DCBs 2-1 to 2-10, and transmit each DCB by performing channel encoding. The size of the DCBs generated from TB 2 (i.e., DCBs 2-1 to 2-10) (let's call this CBS2) may not be the same as the sizes of the DCBs generated from TB 1 (i.e., DCBs 1-1 to 1-15) and PCBs (i.e., PCBs 1-1 and 1-2) (let's call this CBS1).

[0331] The terminal can perform channel decoding on each of the received DCBs, i.e., DCBs 2-1 to 2-10. If all DCBs are decoded without error, the terminal can combine the DCBs to obtain the PTB and MAC PDU 2. The terminal can obtain the PTB even if the DCBs including the PTB and PTB CRC are decoded without error and errors occur in the remaining DCBs.

[0332] The terminal can acquire DCBs 1-8 and 1-9 of TB 1 from the acquired PTB. In addition, the terminal can acquire the PCB required to restore DCB 1-13 of TB 1, i.e., PCB 1-1. The terminal can restore DCB 1-13 by performing erasure decoding using DCBs 1-1 to 1-7, 1-10 to 1-12, and 1-14 to 1-15 decoded without error in the initial transmission of TB 1, i.e., PDSCH 1, and DCBs 1-8 and 1-9 acquired from the PTB of TB 2 received on PDSCH 2, and PCB 1-1 acquired from the PTB of TB 2. The terminal can obtain TB 1 and MAC PDU 1 by combining all DCBs from DCB 1-1 to DCB 1-15, including the restored DCBs.

[0333] Erasure codes such as Raptor code, Random Linear code, and Reed-Solomon (RS) code can be used to generate one or more PCBs from DCBs. However, the Forward Error Correction (FEC) codes that can be used to generate PCBs are not limited to these erasure codes.

[0334] <HARQ-ACK 피드백(feedback)>

[0335] In the examples of FIGS. 26 and 27, and FIGS. 28 and 29, the terminal may feedback the number of DCBs in which transmission errors occurred via HARQ-ACK. The number of DCBs in which errors occurred at the terminal may be equal to the total number of DCBs transmitted by the base station in the worst case, i.e., when errors occur in all DCBs.

[0336] Therefore, to express all cases in which the terminal can feedback, bits may be needed to express the maximum number of DCBs that the base station can transmit, starting from 0. For example, if the maximum number of DCBs that the base station can transmit is 100, 7 bits (2) are required for HARQ-ACK feedback. 7 =128) may be required. In general, as the data transmission rate increases, the maximum number of DCBs also increases, and thus the number of HARQ-ACK feedback bits may also increase. This means that the PUCCH resources required for HARQ-ACK feedback increase.

[0337] To reduce the number of HARQ-ACK feedback bits, the range of DCBs with errors can be divided into several sections and fed back. For example, as shown in Fig. 26, if the total number of DCBs is 15, 2 bits can be used to feed back 0 when there are no DCBs with errors (i.e., when it is an ACK), 1 can be fed back when there are 1 to 5 additional PCBs required, 2 can be fed back when there are 6 to 10, and 3 can be fed back when there are 11 to 15.

[0338] This even division may be inefficient because the probability of having 1 or 2 DCBs with errors may be higher than the probability of having 14 or 15 DCBs. Therefore, it may be efficient to divide the intervals according to the probability distribution of the number of DCBs with errors. For example, let's assume that during the terminal's decoding process, the probability of having an error in 1 DCB is 33%, the probability of having an error in 2 to 4 DCBs is 33%, and the probability of having an error in 5 or more DCBs is 34%. In this case, it may be efficient to feedback 0 for ACK (i.e., when no DCBs have errors), 1 for 1 DCB with errors, 2 for 2 to 4 DCBs, and 3 for 5 or more DCBs.

[0339] The total number of DCBs (let's call this k) may vary depending on the amount of data to be transmitted and channel conditions. Therefore, it may be desirable to divide the intervals proportionally to the total number of DCBs.

[0340] Below, Table 6 is an example of a case where a terminal provides feedback by dividing the number of HARQ-ACK feedback bits unequally according to the probability distribution of the total number of DCBs and the number of DCBs in which errors occurred when the number of HARQ-ACK feedback bits is N.

[0341] α1, α2, ..., α2 which determine the boundaries of HARQ-ACK feedback values ​​in Table 6 N -2 may be a value determined based on the probability distribution of the number of DCBs in which an error will occur. The base station can transmit the information in Table 6 to the terminal through an RRC message, etc. For example, if the base station and the terminal have agreed in advance on how to generate Table 6, the base station may transmit α1, α2, ..., α2 to the terminal through an RRC message, etc. N -2 can be conveyed.

[0342] [Table 6]

[0343]

[0344] For example, when the number of HARQ-ACK feedback bits N is 2, the base station can set α1 and α2 to 100 and 300 for the terminal, respectively. When the base station transmits the first transmission of the data block with 15 DCBs as in TB 1 of FIGS. 26 and 28, i.e., when k is 15, Table 6 can be expressed in specific numbers as in Table 7. The terminal can determine the HARQ-ACK feedback value based on the number of DCBs in which an error occurred and Table 7. According to Table 7, when the terminal feedbacks 1 as HARQ-ACK, the base station can transmit two or more new PCBs. When the terminal feedbacks 2 as HARQ-ACK, the base station can transmit five or more PCBs. When the terminal feedbacks 3 as HARQ-ACK, the base station can retransmit all DCBs of the initial transmission as in the conventional manner.

[0345] [Table 7]

[0346]

[0347] When the second transmission of the base station includes a piggyback TB (PTB), such as TB 2 of FIG. 27 or 29, if TB 2 is transmitted without error, the terminal can recover the error of TB 1 by acquiring the DCB and PCB of the PTB. The terminal feeds back an ACK as a HARQ-ACK for TB 2, and the base station receiving it can know that the terminal has also recovered the error of TB 1 using the DCB and PCB of the PTB.

[0348] However, if an error occurs in some of the DCBs of TB 2 and the UE feeds back a NACK with HARQ-ACK, the base station cannot know whether the error in TB 1 has been recovered or not. If all DCBs including the PTB are decoded without errors and decoding failure occurs only in the DCBs not including the PTB, the UE can recover the transmission error in TB 1 by acquiring the DCBs and PCB of the PTB. In other words, even if the HARQ-ACK of TB 2 is a NACK, the error in TB 1 may be recovered. Therefore, when TB 2 includes a PTB, it may be useful for the UE to additionally feed back the HARQ-ACK of TB 1, which is the TB that needs to be recovered using the PTB, together with the HARQ-ACK of TB 2. The HARQ-ACK for TB 1 fed back together with the HARQ-ACK for TB 2 may consist of 1 bit and may be efficient in feeding back either an ACK (e.g., 0) or a NACK (e.g., 1). The HARQ-ACK for TB 1 (fed back together with the HARQ-ACK for TB 2) may be referred to as a "PTB-related HARQ-ACK" hereinafter.

[0349] The terminal can refer to the PTBI of the DCI to determine whether and how much HARQ-ACK feedback is needed for the TB that needs to be recovered using the PTB. For example, if the PTBI does not indicate the transmission of the PTB (i.e., if the PTBI indicates that the PTB will not be transmitted), the terminal may not transmit the PTB-related HARQ-ACK.

[0350] If the PTBI indicates the transmission of the PTB (i.e., the PTBI indicates that the PTB is transmitted) and the terminal fails to acquire the PTB, the terminal can feedback a NACK with the PTB-related HARQ-ACK. If the PTBI indicates the transmission of the PTB and the terminal acquires the PTB, the terminal can determine the HARQ-ACK feedback value based on the PCB / DCB acquired from the PTB and whether the TB that needs to be recovered has been recovered using the PCB / DCB. That is, if the TB that needs to be recovered has been recovered, an ACK can be fed back, and if not, a NACK can be fed back.

[0351] In this way, when the HARQ-ACK of the TB to be recovered using the PTB is fed back using 1 bit, if the number of bits of the HARQ-ACK for the TB that does not include the PTB (hereinafter referred to as "ordinary HARQ-ACK") is N, the HARQ-ACK of the TB that includes the PTB can be (N+1). When transmitting a HARQ-ACK of (N+1) bits using the same radio resources, the reception quality may deteriorate compared to when transmitting a HARQ-ACK of N bits, which may increase the possibility of the base station receiving it incorrectly.

[0352] To improve this problem, when PTB-related HARQ-ACK is fed back using 1 bit, HARQ-ACK of TB including PTB can be fed back using (N-1) bits, so that the total number of HARQ-ACK feedback bits can be maintained as N.

[0353] That is, a total of N bits of information are fed back by adding 1 bit, which is HARQ-ACK for TB (e.g., TB 1) to be recovered using PTB, and (N-1) bits, which is HARQ-ACK for TB including PTB (e.g., TB 2).

[0354] Hereinafter, the (N-1) bit HARQ-ACK transmitted together with the PTB-related HARQ-ACK will be referred to as “compact HARQ-ACK.”

[0355] Figure 30 is an example of HARQ-ACK feedback of a terminal depending on whether PTB is transmitted.

[0356] Referring to Figure 30, when PTBI is 0, it means that PTB is not transmitted, and when PTBI is 1, it means that PTB is transmitted. PTBI can be included in DCI that schedules PDSCH.

[0357] When PTBI is 0, the terminal can feed back N-bit Ordinary HARQ-ACK. On the other hand, when PTBI is 1, the terminal can feed back 1-bit PTB-related HARQ-ACK and (N-1)-bit Compact HARQ-ACK.

[0358] The terminal can determine an (N-1)-bit shortened HARQ-ACK from an N-bit regular HARQ-ACK determined based on the number of DCBs in which an error occurred. Tables 8 and 9 are examples of mapping an N-bit regular HARQ-ACK value to an (N-1)-bit shortened HARQ-ACK value.

[0359] In the case of Table 8 below, among the HARQ-ACK values, 0 to 2 are usually used. N-1 -2 is used as is in the shortened HARQ-ACK and is usually 2 among the HARQ-ACK values. N-1 -1 to 2 N -1 shortens HARQ-ACK to 2 N-1This is a method of matching with -1. This method has the advantage of being easy to implement, but half of the total HARQ-ACK values ​​are matched with a single shortened HARQ-ACK value, which may reduce feedback and retransmission efficiency.

[0360] [Table 8]

[0361]

[0362] Table 9 below shows that among the normal HARQ-ACK values, 0 corresponding to ACK is directly mapped to the shortened HARQ-ACK value 0, and among the normal HARQ-ACK values, 1 to 2 N Up to -2, the two values ​​of (2n-1) and 2n, which are usually HARQ-ACK values, are shortened to n(=1 ... 2) of HARQ-ACK. N-1 -1) and the last 2, which is usually the HARQ-ACK value, N -1 is 2 for shortened HARQ-ACK N-1 This is a method of corresponding to -1. This method can improve feedback and retransmission efficiency compared to the method in Table 8 by corresponding the normal N-bit HARQ-ACK value to a shortened HARQ-ACK value of (N-1) bits relatively evenly.

[0363] [Table 9]

[0364]

[0365] Another way to determine the shortened HARQ-ACK is for the base station to provide separate β1, β2, ..., β2 that determine the boundaries of the shortened HARQ-ACK feedback values ​​to the terminal. (N-1) -2 can be transmitted. In this case, the terminal can determine the shortened HARQ-ACK value as shown in Table 10.

[0366] [Table 10]

[0367]

[0368] In the examples of FIGS. 26 and 27, and FIGS. 28 and 29, if the terminal receiving TB 2 normally recovers the TB (i.e., TB 1) that needs to be recovered using PTB and feeds back the PTB-related HARQ-ACK as an ACK, the base station receiving this can estimate that no transmission error occurred in the DCBs including PTB data among the DCBs of TB 2.

[0369] In some cases, the terminal may receive TB 1 without error and feed back an ACK as HARQ-ACK, but the base station may erroneously receive it as NACK and transmit a PTB through TB ​​2. In this case, even if a transmission error occurs in the DCBs containing PTB data, except for the first DCB containing the PTB size and header, the terminal can transmit an ACK as HARQ-ACK, and the base station does not need to perform retransmission to recover the PTB.

[0370] In this way, when PTB-related HARQ-ACK is fed back as ACK, the terminal can generate a shortened HARQ-ACK by considering only transmission errors of the remaining DCBs excluding DCBs containing only PTB data. At this time, when applying Table 6 or Tables 8 to 10 to obtain a shortened HARQ-ACK value, the number of DCBs (k) may be the number of the remaining DCBs excluding DCBs containing only PTB data, rather than the total number of DCBs of TB 2.

[0371] For example, in FIG. 27, PTB data is transmitted through DCB 2-1 to DCB 2-4, and DCB 2-4 may also include data of MAC PDU 2. In this case, the terminal may determine a shortened HARQ-ACK based on the number of DCBs in which transmission errors occurred among the seven DCBs from DCB 2-4 to DCB 2-10.

[0372] As another example, in FIG. 29, PTB data is transmitted through DCB 2-1 to DCB 2-5, and DCB 2-5 may also include data of MAC PDU 2. In this case, the terminal may determine a shortened HARQ-ACK based on the number of DCBs in which transmission errors occurred among the six DCBs from DCB 2-5 to DCB 2-10.

[0373] A base station that receives a PTB-related HARQ-ACK as an ACK (i.e., the PTB-related HARQ-ACK is an ACK) and a shortened HARQ-ACK as a NACK (i.e., the shortened HARQ-ACK is a NACK) can perform retransmission by generating one or more PCBs using only the remaining DCBs excluding the DCBs containing only PTB data in order to recover from a transmission error that occurred in the remaining DCBs excluding the DCBs containing only PTB data.

[0374] Figures 31 and 32 illustrate the operation when a terminal receiving TB 2 in the examples of Figures 28 and 29 fails to decode only DCB 2-8.

[0375] Referring to FIG. 31, since DCB 2-1 to DCB 2-5 containing data of PTB 1 (piggyback TB 1) are all successfully decoded, the terminal can recover all errors of TB 1 by obtaining DCB 1-8, DCB 1-9, and PCB 1-1 from PTB 1.

[0376] Therefore, the terminal can feedback the PTB-related HARQ-ACK (i.e., the HARQ-ACK for TB 1 that needs to be recovered using the PTB included in TB 2) as an ACK. In addition, the terminal can feedback the occurrence of a transmission error in one of the six DCBs from DCB 2-5 to DCB 2-10 that contain data other than PTB 1 (i.e., new data MAC PDU 2) as a shortened HARQ-ACK.

[0377] Referring to FIG. 32, a base station that has received a PTB-related HARQ-ACK and a shortened HARQ-ACK can generate one PCB, i.e., PCB 2-1, from DCBs 2-5 to 2-10, excluding DCBs 2-1 to 2-4, which contain only PTB data. The base station can transmit a new PTB 2 (piggyback TB 2) containing PCB 2-1 to the terminal through a new TB 3 and PDSCH 3.

[0378] If TB 3 only contains PTB 2, the PTB CRC can be omitted. A terminal that receives TB 3 without error can recover transmission errors in TB 2 by acquiring PTB 2 and PCB 2-1. The terminal can feedback both the PTB-related HARQ-ACK (i.e., the HARQ-ACK for TB 2 that must be recovered using the PTB included in TB 3) and the shortened HARQ-ACK for TB 3 as ACKs.

[0379] In the examples of FIGS. 31 and 32, let's assume that the DCB that the terminal that received TB 2 failed to decode is not DCB 2-8, but a DCB including a part of PTB 1 (e.g., DCB 2-2). In this case, the terminal can receive TB 3 to recover TB 2 and then secure PTB 1 to recover the error in TB 1. If a transmission error also occurs in TB 3, the recovery of TB 2 and the acquisition of PTB 1 may be delayed, which may also delay the error recovery in TB 1. In order to reduce the transmission delay of TB 1, the base station may retransmit the entire TB 1 or the entire TB 2 without transmitting TB 3 including PTB 2 if the PTB-related HARQ-ACK is NACK.

[0380] Table 11 illustrates the number of bits of PTB-related HARQ-ACK, normal HARQ-ACK, and shortened HARQ-ACK according to the value of PTBI, and the method of determining the normal HARQ-ACK value and shortened HARQ-ACK value according to the PTB-related HARQ-ACK value.

[0381] [Table 11]

[0382]

[0383] In Table 11, when the number of bits N of a normal HARQ-ACK is 2, when transmitting a PTB-related HARQ-ACK, the shortened HARQ-ACK becomes 1 bit and cannot convey the number of DCBs in which a transmission error occurred, and only ACK or NACK can be used as feedback. In this case, as in TB 2 of Fig. 31, when a transmission error occurred in one or more DCBs, even if the shortened HARQ-ACK is the same as NACK, the DCBs that the base station must retransmit may vary depending on the value of the PTB-related HARQ-ACK.

[0384] Specifically, if the PTB-related HARQ-ACK is NACK and the shortened HARQ-ACK is NACK, the base station can retransmit all DCBs. If the PTB-related HARQ-ACK is ACK and the shortened HARQ-ACK is NACK, the base station can retransmit only the remaining DCBs except for the DCBs containing only PTB data.

[0385] For example, in the examples of FIGS. 31 and 32, if the PTB-related HARQ-ACK is NACK and the shortened HARQ-ACK is NACK, the base station can retransmit all DCBs of TB 2, i.e., DCB 2-1 to DCB 2-10. If the PTB-related HARQ-ACK is ACK and the shortened HARQ-ACK is NACK, the base station can retransmit only DCB 2-5 to DCB 2-10 without retransmitting DCB 2-1 to DCB 2-4, which contain only PTB data.

[0386] When a base station receives a TB including a PTB from a terminal, the base station can set, through an RRC message, whether to provide feedback of a PTB-related HARQ-ACK, whether to use a shortened HARQ-ACK, and whether to exclude DCBs containing only PTB data when the PTB-related HARQ-ACK value is ACK when determining the shortened HARQ-ACK value.

[0387] <PTB 헤더(header)의 구성>

[0388] To support the examples described above, the header of a PTB containing one or more DCBs or one or more PCBs may contain the following information:

[0389] 1) HARQ PN (process number): This may refer to the HARQ process number to which the DCB included in the PTB belongs and to which the TB used to generate the PCB was transmitted. In the examples of FIGS. 26 and 27, this may correspond to the HARQ process number to which TB 1 was transmitted.

[0390] 2) TB ID: If multiple TBs can be scheduled in one HARQ PN, a TB ID may be included to specify which TB it is.

[0391] 3) CBS: This refers to the CB size of DCB and PCB, and can be expressed in bytes, for example.

[0392] 4) Number of DCBs.

[0393] 5) Number of PCBs.

[0394] 6) Start DCB index for PCB generation: This is the first index of the DCBs used to generate one or more PCBs included in the PTB. For example, in the examples of FIGS. 31 and 32, if the indices of DCBs 2-1 to 2-10 are 0 to 9, and PCB 2-1 is generated using DCBs 2-5 to 2-10, the value of the start DCB index for PCB generation is 4. If all DCBs are used to generate the PCB, the value of the start DCB index for PCB generation is 0.

[0395] 7) Start PCB index: This is the index information of the first PCB included in the PTB. The indices of the second and subsequent PCBs included in the PTB increase sequentially from the index of the first PCB.

[0396] 8) DCB Index: This is the index information of each DCB, and can be sequentially included as many times as the number of DCBs. For example, in the examples of FIGS. 28 and 29, if the indices of DCB 1-1 to DCB 1-15 are 0 to 14, the header of the PTB including DCB 1-8 and DCB 1-9 can sequentially include two DCB indices, 7 and 8.

[0397] According to the present disclosure, data and parity information for error recovery and new data can be transmitted through one new data block (TB), thereby increasing transmission speed and reducing transmission delay.

[0398] In addition, transmission efficiency can be improved by retransmitting only the necessary amount of data or parity information, and HARQ-ACK feedback and DCI signaling overhead can be reduced compared to CBG-based transmission technology.

[0399] Figure 33 illustrates a method for receiving a data block by a terminal in a wireless communication system.

[0400] Referring to FIG. 33, a terminal receives a first data block including a plurality of partial blocks from another device (e.g., a network, a base station, another terminal, a repeater, an IAB node, etc.) (S331). The first data block may be, for example, a transport block (TB), and TB 1 described in FIGS. 26 to 29 may correspond to the first data block. Data (e.g., MAC PDU 1 described in FIGS. 26 and 28) is transmitted to the terminal through the first data block.

[0401] Before receiving the first data block, the terminal may receive first downlink control information (DCI). The first DCI may include first HARQ feedback timing information indicating a time point (e.g., a subslot, a slot, a subframe) at which HARQ-ACK (Hybrid Automatic Repeat reQuest-Acknowledgement) information for data reception is to be transmitted, and scheduling information for scheduling the first data block.

[0402] Alternatively, depending on the embodiment, the terminal may semi-statically set / receive HARQ feedback timing based on a higher layer signal (e.g., RRC configuration). For example, if there is no HARQ feedback timing information in the DCI, the terminal may transmit HARQ-ACK information at the time set by the higher layer signal.

[0403] The first data block may include a plurality of sub-blocks. The sub-blocks may be, for example, DCBs as described in FIGS. 26 to 29. For example, the first data block may be divided into a plurality of sub-blocks through a division procedure (e.g., code block segmentation) and transmitted. For example, FIG. 26 illustrates a case where a CRC is added to TB 1 and then divided into 15 DCBs, such as DCB 1-1 to DCB 1-15, through code block segmentation and then transmitted.

[0404] The above-described plurality of partial blocks are generated from a first data block, and decoding the plurality of partial blocks allows the first data block to be recovered. In this sense, it can be said that the first data block includes the plurality of partial blocks.

[0405] The terminal transmits first HARQ-ACK (Hybrid Automatic Repeat reQuest-Acknowledgement) information indicating the number of partial blocks in which errors occurred among the partial blocks (S332). For example, the terminal performs channel decoding on the partial blocks, and if there are partial blocks (e.g., DCBs) in which decoding fails due to unrecovered errors during the process, the terminal feeds back the number of partial blocks in which errors occurred to the other device as the first HARQ-ACK information. The terminal may transmit the first HARQ-ACK information at a time based on the first HARQ feedback timing information.

[0406] For example, if the first HARQ-ACK information indicates that the number of DCBs in which errors occurred is 0, the other device may consider the first HARQ-ACK information to indicate an ACK, and if not, may consider it to indicate a NACK.

[0407] The terminal receives a piggyback data block including at least one parity block and a second data block including new data (S333).

[0408] The terminal may receive a second DCI before receiving the second data block. The second DCI may include second HARQ feedback timing information indicating a time to transmit HARQ-ACK information for data reception and scheduling information for scheduling the second data block. In some embodiments, the second DCI may also include an indicator (e.g., the PTBI described above) indicating that the second data block includes the piggyback data block (or whether the piggyback data block is included).

[0409] Alternatively, depending on the embodiment, the terminal may semi-statically set / provide HARQ feedback timing based on a higher layer signal (e.g., RRC configuration).

[0410] The other device (e.g., base station) that receives the first HARQ-ACK information can perform erasure encoding on partial blocks (e.g., DCBs, DCB 1-1 to 1-15) before channel coding is performed, thereby generating a sufficient number of parity blocks for the terminal to recover errors. The parity block is data including parity information for recovering the partial block (DCB), and may be, for example, a parity code block (PCB) described in FIGS. 27 and 29.

[0411] For example, when performing erasure encoding using an optimal erasure code, parity blocks can be generated in the number of partial blocks in which the error occurred. When performing erasure encoding using a near-optimal erasure code, parity blocks can be generated in the number of partial blocks in which the error occurred or in a number greater than that (e.g., the number of partial blocks in which the error occurred + 1). In this sense, it can be seen that the at least one parity block is determined based on the first HARQ-ACK information.

[0412] At least one parity block is included in a piggyback data block, and the piggyback data block is included in a second data block. The piggyback data block may be, for example, a piggyback TB as described in FIGS. 27 and 29 . The second data block may be, for example, TB 2 as described in FIGS. 27 and 29 . The new data included in the second data block may be, for example, MAC PDU 2 as described in FIGS. 27 and 29 .

[0413] From the base station's perspective, the number of the HARQ process transmitting the second data block may be the same as the number of the HARQ process transmitting the first data block. The method according to the present disclosure differs from the prior art in that the second data block containing new data has a different HARQ process number than the HARQ process number of the first data block, and the method according to the present disclosure has the effect of increasing the reusability of the HARQ process number.

[0414] In some embodiments, the piggyback data block may further include partial blocks in which an error is expected to occur in the first data block. For example, as described in FIG. 28, if some partial blocks of the first data block (TB 1) are preempted by URLLC data and thus have a high probability of causing a transmission error, the base station can know this before receiving HARQ-ACK information from the terminal. Therefore, some partial blocks in which the URLLC data is preempted and thus have a high probability of causing a transmission error are included in the piggyback data block included in the transmission of the second data block and transmitted. This has been described in detail in FIGS. 28 and 29. Here, a partial block preempted by URLLC data is presented as an example of a partial block in which an error is expected to occur in the first data block, but the present invention is not necessarily limited thereto. That is, if the base station can know a partial block in which an error is expected to occur in the first data block for a reason other than preemption of URLLC data, the base station may include the corresponding partial block in the piggyback data block.

[0415] The terminal receives i) a piggyback data block including the partial blocks in which an error is expected to occur in the first data block and the at least one parity block, and ii) a second data block including new data, and can recover the first data block based on the piggyback data block. This has been described above with reference to FIG. 29. FIG. 29 exemplifies a case in which the piggyback data block includes two partial blocks (DCBs) and one parity block (PCB). According to an embodiment, it is also possible to include only the partial blocks in which an error is expected to occur in the first data block without including a parity block in the piggyback data block.

[0416] The terminal transmits second HARQ-ACK information, which includes information (e.g., 1-bit information) indicating whether the first data block (e.g., TB 1) has been successfully recovered based on the piggyback data block (e.g., piggyback TB) and count information indicating the number of partial blocks in which errors occurred among the partial blocks of the second data block (e.g., TB 2), to the other device (S334). That is, the second HARQ-ACK information may include i) information indicating whether the first data block has been successfully recovered, and ii) count information indicating the number of partial blocks in which errors occurred among the partial blocks of the second data block. This process has been described above with reference to FIGS. 26 and 27, FIGS. 28 and 29, and FIGS. 31 and 32.

[0417] The terminal can transmit the second HARQ-ACK information at a time based on the second HARQ feedback timing information.

[0418] When the second HARQ-ACK information is N bits (N is a natural number greater than or equal to 2), the information indicating whether the first data block has been successfully recovered is 1 bit, and the number information indicating the number of partial blocks in which an error occurred among the partial blocks of the second data block may be N-1 bits. This has been described above with reference to FIG. 30.

[0419] As described above, before receiving the second data block, the terminal may receive a second DCI scheduling the second data block. The second DCI may include an indicator (e.g., the PTBI described above) indicating that the second data block includes the piggyback data block (or whether the piggyback data block is included).

[0420] For example, the terminal can determine whether to provide HARQ-ACK feedback and its value for a data block that needs to be recovered using a piggyback data block (e.g., PTB) by referring to the PTBI included in the downlink control information. If the PTBI does not indicate transmission of the PTB, the terminal may not transmit the PTB-related HARQ-ACK. If the PTBI indicates transmission of the PTB but the terminal fails to acquire the PTB, the terminal may feed back NACK as the PTB-related HARQ-ACK. If the PTBI indicates transmission of the PTB and the terminal acquires the PTB, the terminal may determine the HARQ-ACK feedback value based on the data (PCB, DCB) acquired from the PTB and whether the TB that needs to be recovered has been recovered using the PCB. That is, if the TB that needs to be recovered has been recovered, ACK may be fed back, and if not, NACK may be fed back.

[0421] The aforementioned method can improve problems such as reduced transmission speed and increased transmission delay due to data retransmission, while increasing system capacity. Furthermore, by increasing the reusability of HARQ process numbers, it can achieve effects such as increased transmission speed and reduced transmission delay. In beamforming systems such as mmWave and THz, system capacity can also be increased, and the QoS of services requiring low-latency, ultra-high-speed transmission, such as XR, can be improved.

[0422] Figure 34 illustrates a method performed by a base station in a wireless communication system.

[0423] Referring to FIG. 34, the base station transmits a first data block including a plurality of partial blocks to the terminal (S341). Before transmitting the first data block, the base station may transmit a first DCI. The first DCI may include first HARQ feedback timing information that informs the terminal of the time to transmit HARQ-ACK (Hybrid Automatic Repeat reQuest-Acknowledgement) information regarding data reception, and scheduling information that schedules the first data block.

[0424] The base station receives, from the terminal, first HARQ-ACK information indicating the number of partial blocks in which errors occurred among the partial blocks (S342). The base station can receive the first HARQ-ACK information at a time based on the first HARQ feedback timing information.

[0425] The base station transmits to the terminal a piggyback data block including at least one parity block and a second data block including new data (S343). Before transmitting the second data block, the base station may transmit a second DCI. The second DCI may include, for example, at least one of second HARQ feedback timing information indicating a time point for transmitting HARQ-ACK information for data reception, scheduling information for scheduling the second data block, and a PTBI.

[0426] The base station receives second HARQ-ACK information from the terminal, which includes information indicating whether the first data block has been successfully recovered based on the piggyback data block and number information indicating the number of partial blocks in which errors occurred among the partial blocks of the second data block (S344). The base station may receive the second HARQ-ACK information at a time based on the second HARQ feedback timing information.

[0427] This process has been described above with reference to FIGS. 26 to 33.

[0428] Figure 35 illustrates a signaling process between a first device and a second device.

[0429] Referring to FIG. 35, a first device (e.g., a base station) transmits a first data block including a plurality of partial blocks to a second device (e.g., a terminal) (S351). Although not illustrated in FIG. 35, according to an embodiment, the first device may transmit a first DCI before transmitting the first data block. The first DCI may include first HARQ feedback timing information that informs the second device of a time point at which to transmit HARQ-ACK (Hybrid Automatic Repeat reQuest-Acknowledgement) information for data reception, and scheduling information that schedules the first data block.

[0430] The second device decodes the partial blocks and transmits to the first device first HARQ-ACK information indicating the number of partial blocks in which errors occurred among the partial blocks (S352). For example, the second device may transmit the first HARQ-ACK information at a time based on the first HARQ feedback timing information.

[0431] The first device generates a piggyback data block including at least one parity block and a second data block including new data and transmits the generated data to the second device (S353). Although not illustrated in FIG. 35, according to an embodiment, the first device may transmit a second DCI before transmitting the second data block. The second DCI may include at least one of second HARQ feedback timing information indicating a time point for transmitting HARQ-ACK information for data reception, scheduling information for scheduling the second data block, and a PTBI.

[0432] After decoding the second data block, the second device generates second HARQ-ACK information including information indicating whether the first data block has been successfully recovered based on the piggyback data block and count information indicating the number of partial blocks in which errors occurred among the partial blocks of the second data block, and then transmits (feeds back) the second HARQ-ACK information to the first device (S354). For example, the second device may transmit the second HARQ-ACK information at a time based on the second HARQ feedback timing information.

[0433] This process has been described above with reference to FIGS. 26 to 33.

[0434] Embodiments according to the present disclosure may be implemented by various means, for example, hardware, firmware, software, or a combination thereof. In the case of hardware implementation, an embodiment of the present disclosure may be implemented by one or more application specific integrated circuits (ASICs), digital signal processors (DSPs), digital signal processing devices (DSPDs), programmable logic devices (PLDs), field programmable gate arrays (FPGAs), processors, controllers, microcontrollers, microprocessors, etc.

[0435] For example, the method described in FIG. 33 can be performed by a computer readable medium (CRM) that stores instructions to be performed by at least one processor. The CRM performs the following operations: receiving a first data block including a plurality of partial blocks; transmitting first Hybrid Automatic Repeat reQuest-Acknowledgement (HARQ-ACK) information indicating a number of partial blocks in which errors occur among the partial blocks; receiving a piggyback data block including at least one parity block and a second data block including new data; and transmitting second HARQ-ACK information including information indicating whether the first data block was successfully recovered based on the piggyback data block and number information indicating a number of partial blocks in which errors occur among the partial blocks of the second data block.

[0436] When implemented via firmware or software, an embodiment of the present specification may be implemented in the form of a module, procedure, function, or the like that performs the functions or operations described above. The software code may be stored in memory and executed by a processor. The memory may be located within or external to the processor and may exchange data with the processor via various known means.

[0437] The claims set forth in this specification may be combined in various ways. For example, the technical features of the method claims of this specification may be combined and implemented as a device, and the technical features of the device claims of this specification may be combined and implemented as a method. Furthermore, the technical features of the method claims and the technical features of the device claims of this specification may be combined and implemented as a device, and the technical features of the method claims and the technical features of the device claims of this specification may be combined and implemented as a method.

Claims

1. In a method for receiving a data block of a terminal in a wireless communication system, Receive first downlink control information (DCI), wherein the first DCI includes first HARQ feedback timing information indicating a time to transmit HARQ-ACK (Hybrid Automatic Repeat reQuest-Acknowledgement) information for data reception, Receive a first data block including a plurality of partial blocks scheduled by the first DCI, Transmitting first HARQ-ACK (Hybrid Automatic Repeat reQuest-Acknowledgement) information indicating the number of partial blocks in which an error occurred among the above partial blocks at a time based on the first HARQ feedback timing information, Receive a second DCI, wherein the second DCI includes second HARQ feedback timing information indicating a time to transmit HARQ-ACK information for data reception, Receive a piggyback data block including at least one parity block scheduled by the second DCI and a second data block including new data, and A method characterized in that the second HARQ-ACK information including information indicating whether the first data block has been successfully recovered based on the piggyback data block and number information indicating the number of partial blocks in which an error occurred among the partial blocks of the second data block is transmitted at a time based on the second HARQ feedback timing information.

2. A method according to claim 1, wherein the second DCI scheduling the second data block includes an indicator indicating that the piggyback data block is included in the second data block.

3. A method according to claim 1, characterized in that the at least one parity block is determined based on the first HARQ-ACK information.

4. A method according to claim 1, characterized in that the piggyback data block further includes a partial block in which an error is expected to occur in the first data block.

5. A method according to claim 4, characterized in that the first data block is recovered based on the partial block in which an error is expected to occur in the first data block and the at least one parity block.

6. A method according to claim 1, characterized in that the piggyback data block includes at least one of size information of the piggyback data block, information about at least one partial block included in the piggyback data block and the at least one parity block, and CRC (Cyclic Redundancy Check) information of the piggyback data block.

7. A method according to claim 6, characterized in that the size information of the piggyback data block is located a certain offset after the start of the second data block or a certain offset before the end of the second data block.

8. In the first paragraph, when the second HARQ-ACK information is N bits (N is a natural number greater than or equal to 2), the information indicating whether the first data block has been successfully recovered is 1 bit, and the number information indicating the number of partial blocks in which an error occurred among the partial blocks of the second data block is characterized in that the method is N-1 bits.

9. A terminal operating in a wireless communication system, At least one transceiver; At least one processor connected to at least one transceiver; and At least one memory operatively connectable to at least one processor, At least one processor, Receive first downlink control information (DCI), wherein the first DCI includes first HARQ feedback timing information indicating a time to transmit HARQ-ACK (Hybrid Automatic Repeat reQuest-Acknowledgement) information for data reception, Receive a first data block including a plurality of partial blocks scheduled by the first DCI, Transmitting first HARQ-ACK (Hybrid Automatic Repeat reQuest-Acknowledgement) information indicating the number of partial blocks in which an error occurred among the above partial blocks at a time based on the first HARQ feedback timing information, Receive a second DCI, wherein the second DCI includes second HARQ feedback timing information indicating a time to transmit HARQ-ACK information for data reception, Receive a piggyback data block including at least one parity block scheduled by the second DCI and a second data block including new data, and A terminal characterized in that it transmits second HARQ-ACK information including information indicating whether the first data block has been successfully recovered based on the piggyback data block and number information indicating the number of partial blocks in which an error occurred among partial blocks of the second data block at a time based on the second HARQ feedback timing information.

10. A terminal according to claim 9, wherein the second DCI for scheduling the second data block includes an indicator indicating that the piggyback data block is included in the second data block.

11. A terminal according to claim 9, wherein at least one parity block is determined based on the first HARQ-ACK information.

12. A terminal according to claim 9, wherein the piggyback data block further includes a partial block in which an error is expected to occur in the first data block.

13. A terminal characterized in that, in the 12th paragraph, the first data block is recovered based on the partial block in which an error is expected to occur in the first data block and the at least one parity block.

14. A terminal according to claim 9, wherein the piggyback data block includes at least one of size information of the piggyback data block, information about at least one partial block included in the piggyback data block and the at least one parity block, and CRC (Cyclic Redundancy Check) information of the piggyback data block.

15. A terminal characterized in that, in the 14th paragraph, the size information of the piggyback data block is located after a certain offset from the start of the second data block, or before a certain offset from the end of the second data block.

16. In the 9th paragraph, when the second HARQ-ACK information is N bits (N is a natural number greater than or equal to 2), the information indicating whether the first data block has been successfully recovered is 1 bit, and the number information indicating the number of partial blocks in which an error occurred among the partial blocks of the second data block is a terminal characterized in that the number is N-1 bits.

17. A processing device operating in a wireless communication system, at least one processor; and At least one memory operatively connectable to at least one processor, At least one processor of the above: Receive first downlink control information (DCI), wherein the first DCI includes first HARQ feedback timing information indicating a time to transmit HARQ-ACK (Hybrid Automatic Repeat reQuest-Acknowledgement) information for data reception, Receive a first data block including a plurality of partial blocks scheduled by the first DCI, Transmitting first HARQ-ACK (Hybrid Automatic Repeat reQuest-Acknowledgement) information indicating the number of partial blocks in which an error occurred among the above partial blocks at a time based on the first HARQ feedback timing information, Receive a second DCI, wherein the second DCI includes second HARQ feedback timing information indicating a time to transmit HARQ-ACK information for data reception, Receive a piggyback data block including at least one parity block scheduled by the second DCI and a second data block including new data, and A processing device characterized in that it transmits second HARQ-ACK information including information indicating whether the first data block has been successfully recovered based on the piggyback data block and number information indicating the number of partial blocks in which an error occurred among the partial blocks of the second data block at a time based on the second HARQ feedback timing information.

18. In a computer readable medium (CRM) storing instructions causing an operation to be performed by at least one processor, the operation comprising: An operation of receiving first downlink control information (DCI), wherein the first DCI includes first HARQ feedback timing information indicating a time to transmit HARQ-ACK (Hybrid Automatic Repeat reQuest-Acknowledgement) information for data reception. An operation of receiving a first data block including a plurality of partial blocks scheduled by the first DCI; An operation of transmitting first HARQ-ACK (Hybrid Automatic Repeat reQuest-Acknowledgement) information indicating the number of partial blocks in which an error occurred among the above partial blocks at a time based on the first HARQ feedback timing information; An operation of receiving a second DCI, wherein the second DCI includes second HARQ feedback timing information indicating a time to transmit HARQ-ACK information for data reception; An operation of receiving a piggyback data block including at least one parity block and a second data block including new data, scheduled by the second DCI, and A CRM characterized by comprising an operation of transmitting second HARQ-ACK information including information indicating whether the first data block has been successfully recovered based on the piggyback data block and number information indicating the number of partial blocks in which an error occurred among the partial blocks of the second data block at a time based on the second HARQ feedback timing information.

19. In a method performed by a base station in a wireless communication system, Transmitting first downlink control information (DCI), wherein the first DCI includes first HARQ feedback timing information that indicates when to transmit HARQ-ACK (Hybrid Automatic Repeat reQuest-Acknowledgement) information for data reception, Transmitting a first data block including a plurality of partial blocks scheduled by the first DCI, Receive first HARQ-ACK (Hybrid Automatic Repeat reQuest-Acknowledgement) information indicating the number of partial blocks in which an error occurred among the above partial blocks at a time based on the first HARQ feedback timing information, Transmitting a second DCI, wherein the second DCI includes second HARQ feedback timing information indicating a time to transmit HARQ-ACK information for data reception, Transmitting a piggyback data block including at least one parity block scheduled by the second DCI and a second data block including new data, and A method characterized in that second HARQ-ACK information including information indicating whether the first data block has been successfully recovered based on the piggyback data block and number information indicating the number of partial blocks in which an error occurred among partial blocks of the second data block is received at a time based on the second HARQ feedback timing information.

20. A base station operating in a wireless communication system, At least one transceiver; at least one processor; and At least one memory operatively connectable to at least one processor, At least one processor, Transmitting first downlink control information (DCI), wherein the first DCI includes first HARQ feedback timing information that indicates when to transmit HARQ-ACK (Hybrid Automatic Repeat reQuest-Acknowledgement) information for data reception, Transmitting a first data block including a plurality of partial blocks scheduled by the first DCI, Receive first HARQ-ACK (Hybrid Automatic Repeat reQuest-Acknowledgement) information indicating the number of partial blocks in which an error occurred among the above partial blocks at a time based on the first HARQ feedback timing information, Transmitting a second DCI, wherein the second DCI includes second HARQ feedback timing information indicating a time to transmit HARQ-ACK information for data reception, Transmitting a piggyback data block including at least one parity block scheduled by the second DCI and a second data block including new data, and A base station characterized in that it receives second HARQ-ACK information including information indicating whether the first data block has been successfully recovered based on the piggyback data block and number information indicating the number of partial blocks in which an error occurred among partial blocks of the second data block at a time based on the second HARQ feedback timing information.

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