Method and device for transmitting and receiving downlink control channel in wireless communication system

Abstract

Disclosed are a method and device for performing downlink transmission and reception in a wireless communication system. The method according to an embodiment of the present disclosure may comprise the steps in which: a terminal receives, from a base station, configuration information including first information related to a physical downlink control channel (PDCCH) candidate for each aggregation level (AL); and the terminal monitors at least one PDCCH candidate on the basis of the first information, wherein the configuration information includes the type of a first modulation order (MO) for at least one first control channel element (CCE) among a plurality of CCEs for each AL.

Description

Method and device for transmitting and receiving a downlink control channel in a wireless communication system

[0001] The present disclosure relates to a wireless communication system, and more specifically, to a method and apparatus for transmitting and receiving a downlink control channel in a wireless communication system.

[0002] The 5th generation (5G) wireless communication system is a successor technology to 4G LTE (long term evolution) and is a new clean-slate type mobile communication system with characteristics such as high performance, low latency, and high availability. In the case of 5G NR (New Radio), all available spectrum resources can be utilized, ranging from low-frequency bands below 1 GHz to intermediate frequency bands between 1 GHz and 10 GHz, and high-frequency (or millimeter wave) bands above 24 GHz. Based on the foundational technology of 5G wireless communication, 6G wireless communication systems are being developed.

[0003] 6G wireless communication systems are being developed with the goal of (i) very high data rates per device, (ii) a very large number of connected devices, (iii) global connectivity, (iv) very low latency, (v) reduced energy consumption of battery-free IoT (internet of things) devices, (vi) ultra-reliable connectivity, and (vii) connected intelligence with machine learning capabilities. The vision of 6G systems can be seen in four aspects: intelligent connectivity, deep connectivity, holographic connectivity, and ubiquitous connectivity. Various technologies are being researched in consideration of the requirements for 6G systems, such as a peak data rate of 1 Tbps per device, an end-to-end (E2E) latency of 1ms, a maximum spectrum efficiency of 100 bps / Hz, support for mobility of 1000 km / h, satellite integration, artificial intelligence (AI), autonomous vehicles, extended reality (XR), and haptic communication.

[0004] The technical problem of the present disclosure is to provide a method and apparatus for transmitting and receiving a downlink control channel in a wireless communication system.

[0005] The technical problem of the present disclosure is to provide a method and apparatus for indicating different demodulation reference signal (DMRS) densities / modulation orders according to control channel elements (CCE) within a control resource set (CORESET).

[0006] The technical problems to be solved in this disclosure are not limited to those mentioned above, and other technical problems not mentioned will be clearly understood by those skilled in the art to which this disclosure belongs from the description below.

[0007] A method according to one embodiment of the present disclosure comprises: receiving configuration information from a base station by a terminal that includes first information related to a physical downlink control channel (PDCCH) candidate for each aggregation level (AL); and monitoring at least one PDCCH candidate by the terminal based on the first information, wherein the configuration information may include the type of a first modulation order (MO) for at least one first CCE among a plurality of control channel elements (CCEs) for each AL.

[0008] A method according to another embodiment of the present disclosure comprises: a step of transmitting configuration information containing first information related to a physical downlink control channel (PDCCH) candidate for each aggregation level (AL) to a terminal by a base station; and a step of transmitting a PDCCH to the terminal by the base station through at least one PDCCH candidate based on the first information, wherein the configuration information may include a type of first modulation order (MO) for at least one first CCE among a plurality of control channel elements (CCE) for each AL.

[0009] By various embodiments of the present disclosure, a method and apparatus for transmitting and receiving a downlink control channel in a wireless communication system may be provided.

[0010] By various embodiments of the present disclosure, a method and apparatus for indicating different DMRS densities / modulation orders according to the CCE in the CORESET may be provided.

[0011] According to various embodiments of the present disclosure, a large amount of information can be transmitted through a higher-order modulation PDCCH (physical downlink control channel), and thus resource efficiency can be increased.

[0012] The effects obtainable from the present disclosure are not limited to those mentioned above, and other unmentioned effects will be clearly understood by those skilled in the art to which the present disclosure belongs from the description below.

[0013] The accompanying drawings, which are included as part of the detailed description to aid in understanding the present disclosure, provide embodiments of the present disclosure and explain the technical features of the present disclosure together with the detailed description.

[0014] FIG. 1 illustrates an exemplary flexible network topology to which some examples of the present disclosure may be applied.

[0015] FIG. 2 illustrates an exemplary communication system to which some examples of the present disclosure may be applied.

[0016] FIG. 3 illustrates an exemplary wireless device to which some examples of the present disclosure may be applied.

[0017] FIG. 4 illustrates an exemplary communication procedure between a first node and a second node to which some examples of the present disclosure may be applied.

[0018] FIG. 5 illustrates an exemplary functional framework for AI operations to which some examples of the present disclosure may be applied.

[0019] FIG. 6 illustrates an example of operations related to AI model training and AI model inference to which some examples of the present disclosure may be applied.

[0020] FIG. 7 illustrates another example of operations related to AI model training and AI model inference to which some examples of the present disclosure may be applied.

[0021] FIG. 8 illustrates another example of operations related to AI model training and AI model inference to which some examples of the present disclosure may be applied.

[0022] FIG. 9 shows an electromagnetic spectrum to which some examples of the present disclosure may be applied.

[0023] FIG. 10 illustrates an exemplary system information transmission / reception procedure to which some examples of the present disclosure may be applied.

[0024] FIG. 11 illustrates an exemplary beam management procedure to which some examples of the present disclosure may be applied.

[0025] FIGS. 12 and FIGS. 13 show examples of NTN scenarios to which some examples of the present disclosure may be applied.

[0026] FIG. 14 shows examples of sensing operations to which some examples of the present disclosure may be applied.

[0027] FIG. 15 is a flowchart for explaining the operation of a terminal according to one embodiment of the present disclosure.

[0028] FIG. 16 is a flowchart for explaining the operation of a base station according to one embodiment of the present disclosure.

[0029] FIG. 17 is a drawing illustrating a method for determining the type of MO to be applied to a CCE according to one embodiment of the present disclosure.

[0030] FIGS. 18 and 19 are drawings for explaining a method for setting DMRS density according to one embodiment of the present disclosure.

[0031] Hereinafter, preferred embodiments according to the present disclosure will be described in detail with reference to the accompanying drawings. The detailed description disclosed below, together with the accompanying drawings, is intended to describe exemplary embodiments of the present disclosure and is not intended to represent the only embodiment in which the present disclosure may be practiced. The following detailed description includes specific details to provide a complete understanding of the present disclosure. However, those skilled in the art will know that the present disclosure may be practiced without such specific details.

[0032] In some cases, to avoid obscuring the concept of the present disclosure, known structures and devices may be omitted or illustrated in the form of a block diagram focusing on the core functions of each structure and device.

[0033] In the present disclosure, when a component is described as being “connected,” “combined,” or “joined” with another component, this may include not only a direct connection but also an indirect connection in which another component exists between them. Furthermore, in the present disclosure, the terms “comprising” or “having” specify the presence of the mentioned features, steps, actions, elements, and / or components, but do not exclude the presence or addition of one or more other features, steps, actions, elements, components, and / or groups thereof.

[0034] In the present disclosure, terms such as "first," "second," etc. are used solely for the purpose of distinguishing one component from another and are not used to limit the components, nor do they limit the order or importance of the components unless specifically stated otherwise. Accordingly, within the scope of the present disclosure, a first component in one embodiment may be referred to as a second component in another embodiment, and likewise, a second component in one embodiment may be referred to as a first component in another embodiment.

[0035] The terms used in this disclosure are for the description of specific embodiments and are not intended to limit the claims. As used in the description of embodiments and the appended claims, the singular form is intended to include the plural form unless the context clearly indicates otherwise.

[0036] In the present disclosure, "A or B" may mean "only A," "only B," or "both A and B." Alternatively, in the present disclosure, "A or B" may be interpreted as "A and / or B." For example, in the present disclosure, "A, B or C" may mean "only A," "only B," "only C," or "any combination of A, B and C."

[0037] A slash ( / ) or a comma used in the present disclosure may mean "and / or." For example, "A / B" may mean "A and / or B." Accordingly, "A / B" may mean "only A," "only B," or "both A and B." For example, "A, B, C" may mean "A, B or C."

[0038] In the present disclosure, "at least one of A and B" may mean "only A," "only B," or "both A and B." Additionally, in the present disclosure, the expressions "at least one of A or B" or "at least one of A and / or B" may be interpreted as synonymous with "at least one of A and B."

[0039] Additionally, in the present disclosure, "at least one of A, B and C" may 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" may mean "at least one of A, B and C."

[0040] Additionally, parentheses used in the present disclosure may mean "for example." Specifically, when indicated as "control information (PDCCH)," "PDCCH" may be described as an example of "control information." In other words, the "control information" of the present disclosure is not limited to "PDCCH," and "PDCCH" may be described as an example of "control information." Furthermore, even when indicated as "control information (i.e., PDCCH)," "PDCCH" may be described as an example of "control information."

[0041] In the following explanation, '...when, if, in case of' can be replaced with '...based on'.

[0042] Technical features described individually within one drawing in this disclosure may be implemented individually or simultaneously.

[0043] In the present disclosure, a terminal or user equipment (UE) may be a portable device and may be a first node that receives a signal from a base station / second node / integrated access backhaul (IAB) node.

[0044] In the present disclosure, the base station (BS, Base Station) may be a second node / IAB node / Transmission-Reception Point (TRP).

[0045] In the present disclosure, a higher layer parameter may be a parameter configured, pre-configured, or pre-defined for a terminal. For example, a base station or network may transmit the higher layer parameter to the terminal. For example, the higher layer parameter may be transmitted via radio resource control (RRC) signaling or medium access control (MAC) signaling.

[0046] In the present disclosure, "set or defined" may be interpreted as being set to a device through predefined signaling (e.g., System Information Block (SIB), MAC, RRC) from a base station or network. In the present disclosure, "set or defined" may be interpreted as being set to a device through separate signaling or being predefined without separate signaling.

[0047] In the present disclosure, transmitting or receiving a channel includes the meaning of transmitting or receiving information or a signal through said channel. For example, transmitting a control channel means transmitting control information or a signal through the control channel. Similarly, transmitting a data channel means transmitting data information or a signal through the data channel.

[0048] The technology described in this disclosure can be used in various wireless communication 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). CDMA can be implemented with wireless technologies such as UTRA (universal terrestrial radio access) or CDMA2000. TDMA can be implemented with wireless technologies such as GSM (global system for mobile communications), GPRS (general packet radio service), and EDGE (enhanced data rates for GSM evolution). OFDMA can be implemented with wireless technologies such as IEEE (institute of electrical and electronics engineers) 802.11 (Wi-Fi), IEEE 802.16 (WiMAX), IEEE 802-20, E-UTRA (evolved UTRA), LTE (long term evolution), and 5G NR.

[0049] The technology described in this disclosure can be implemented as 6G wireless technology and applied to various 6G systems. For example, 6G systems may have key factors such as eMBB (enhanced mobile broadband), URLLC (ultra-reliable low latency communications), mMTC (massive machine-type communication), AI (artificial intelligence) integrated communication, tactile internet, high throughput, high network capacity, high energy efficiency, low backhaul and access network congestion, and enhanced data security.

[0050] Network structure

[0051] FIG. 1 illustrates an exemplary flexible network topology to which some examples of the present disclosure may be applied.

[0052] To compensate for incomplete areas of network coverage, a network topology in which the split radio access network (RAN) is configured more flexibly and resiliently may be considered. To this end, various nodes such as integrated access backhaul (IAB) nodes, relays, and radio frequency (RF) repeaters, as exemplified in Fig. 1, may be applied, and a non-terrestrial network (NTN) may be integrated. For example, an IAB node may correspond to a node that provides wireless backhaul. For example, a relay may refer to any intermediate point, and in the case of a sidelink relay where a terminal functions as a relay, it may collectively refer to a terminal-to-network (U2N) relay and a terminal-to-terminal (U2U) relay. For example, an RF repeater may correspond to a node that performs simple signal amplification and forwarding functions, and in the case of a network-controlled repeater, it may adjust transmit / receive settings based on information provided by the network as well as signal amplification and forwarding. For example, NTN nodes can correspond to satellites or aircraft that provide NTN coverage that is difficult for terrestrial networks to provide. In addition to these examples, various intermediate points can be introduced to improve the network topology.

[0053] Referring to FIG. 1, a split RAN can support the division of a base station into one centralized unit (CU) and one or more distributed units (DU). The CU and DU may correspond to logical units. The CU may be further divided into a control plane (CP) portion and one or more user plane (UP) portions. Since a failure in the CU-CP affects not only the CU-UP but also the DU, various intermediate points may be introduced to compensate for this.

[0054] An intermediate point may correspond to a terminal or a base station depending on its relative relationship with other nodes. For example, an IAB node may include a mobile-termination (MT) portion and a DU. The MT may connect the IAB node to a donor node. The DU of the IAB node may serve other terminals or connect to other IAB nodes to provide multi-hop wireless backhaul to terminals. For example, an IAB node may correspond to a base station in its relative relationship with a user-side node and to a terminal in its relative relationship with a network-side node.

[0055] In some examples of the present disclosure, the description of a terminal may apply equally to an intermediate point corresponding to a terminal in relation to a network-side endpoint as well as to a user-side endpoint. Similarly, in some examples of the present disclosure, the description of a base station may apply equally to an intermediate point corresponding to a base station in relation to a user-side endpoint as well as to a network-side endpoint. In most cases where there is no additional description of the operation of three or more subjects, the communication subjects in the present disclosure are briefly described by the term terminal and / or base station (or first node and / or second node), wherein the term terminal and / or base station (or first node and / or second node) is interpreted to include or replace any endpoint or any intermediate point in relation to other nodes.

[0056] As such, in some examples of the present disclosure, for the sake of brevity of description, the subject of the operation may be referred to as a terminal and / or base station (or a first node and / or a second node). Additionally, the term terminal and / or base station (or a first node and / or a second node) may be interpreted or substituted as in the following examples: for example, the terminal (or first node) and the base station (or second node) may correspond to a first endpoint and a second endpoint, respectively; may correspond to an endpoint and an intermediate point, respectively; may correspond to an intermediate point and an endpoint, respectively; or may correspond to a first intermediate point and a second intermediate point, respectively.

[0057] In the present disclosure, there may be no intermediate points between the base station and the terminal, or there may be one or more. If intermediate points exist, the intermediate points may correspond to IAB nodes, relays, RF repeaters, NTN nodes, or nodes supporting other functions. The intermediate points may be nodes with a fixed location or nodes with an indefinite location.

[0058] Systems applicable to the present disclosure

[0059] FIG. 2 illustrates an exemplary communication system to which some examples of the present disclosure may be applied.

[0060] The communication system (100) to which the present disclosure applies includes a wireless device (110), a network device (120), and a network (130). Here, the wireless device (110) refers to a device that performs communication using wireless access technology (e.g., LTE, LTE-A, LTE-A pro, NR, 5G, 5G-A, 6G) and may be referred to as a communication / wireless / 5G / 6G device. Although not limited thereto, the wireless device (110) may include a robot (110a), a vehicle (110b-1, 110b-2), an XR (extended reality) device (110c), a hand-held device (110d), a home appliance (110e), an IoT (Internet of Thing) device (110f), and an AI (artificial intelligence) device / server (110g). For example, the vehicle may include a vehicle equipped with wireless communication capabilities, an autonomous vehicle, a vehicle capable of performing inter-vehicle communication, etc. Here, the vehicle (110b-1, 110b-2) may include an unmanned aerial vehicle (UAV) (e.g., a drone). The XR device (110c) includes an augmented reality (AR) / virtual reality (VR) / mixed reality (MR) device and may be implemented in the form of a head-mounted device (HMD), a head-up display (HUD) equipped in a vehicle, a television, a smartphone, a computer, a wearable device, a home appliance, digital signage, a vehicle, a robot, etc. The portable device (110d) may include a smartphone, a smart pad, a wearable device (e.g., a smart watch, smart glasses), a computer (e.g., a laptop, etc.). The home appliance (110e) may include a TV, a refrigerator, a washing machine, etc. The IoT device (110f) may include a sensor, a smart meter, etc. The wireless device (110) may correspond to a terminal (or first node) or an intermediate point.The network device (120) may correspond to a base station (or a second node) or another intermediate point. For example, the network device (120) may also be implemented as a wireless device (110), and a specific wireless device (120a) may operate as a network device (120) to another wireless device (110).

[0061] Wireless devices (110a to 110f) can be connected to a network (130) through a network device (120). AI technology may be applied to the wireless devices (110a to 110f), and the wireless devices (110a to 110f) can be connected to an AI server (110g) through the network (130). The network (130) can be configured using a 3G network, a 4G (e.g., LTE) network, a 5G (e.g., NR) network, or a 6G network. The wireless devices (110a to 110f) may communicate with each other through the network device (120) / network (130), but may also communicate directly (e.g., sidelink communication) without going through the network device (120) / network (130). For example, vehicles (110b-1, 110b-2) can communicate directly (e.g., V2V (vehicle to vehicle) / V2X (vehicle to everything) communication). Also, an IoT device (110f) (e.g., a sensor) can communicate directly with another IoT device (e.g., a sensor) or other wireless devices (110a to 110f).

[0062] Wireless communication / connection (150a, 150b, 150c) can be established between wireless devices (110a to 110f) / network devices (120) and between network devices (120). Here, wireless communication / connection can be established through various wireless access technologies such as uplink / downlink communication (150a), sidelink communication (150b) (or D2D communication), and communication between network devices (150c) (e.g., relay, IAB (integrated access backhaul)). Through wireless communication / connection (150a, 150b, 150c), wireless devices and network devices / wireless devices, and network devices and network devices can transmit / receive wireless signals to / from each other. For example, wireless communication / connection (150a, 150b, 150c) can transmit / receive signals through various physical channels. To this end, based on the various descriptions of the present disclosure, at least some of the following may be performed: a process for setting various configuration information for transmitting / receiving wireless signals, a process for various signal processing (e.g., channel encoding / decoding, modulation / demodulation, resource mapping / demapping, etc.), a resource allocation process, etc.

[0063] Devices applicable to the present disclosure

[0064] FIG. 3 illustrates an exemplary wireless device to which some examples of the present disclosure may be applied.

[0065] Referring to FIG. 3, the wireless device (200) can transmit and receive wireless signals through various wireless access technologies (e.g., LTE, LTE-A, LTE-A pro, NR, 5G, 5G-A, 6G). The wireless device (200) includes at least one processor (202) and at least one memory (204), and may additionally include at least one transceiver (206) and / or at least one antenna (208).

[0066] The processor (202) controls the memory (204) and / or the transceiver (206) and may be configured to implement the descriptions, functions, procedures, proposals, methods, and / or sequences of operation disclosed in this document. For example, the processor (202) may process information within the memory (204) to generate a first information / signal and then transmit a wireless signal containing the first information / signal through the transceiver (206). Additionally, the processor (202) may receive a wireless signal containing a second information / signal through the transceiver (206) and then store information obtained from the signal processing of the second information / signal in the memory (204). The memory (204) may be connected to the processor (202) and may store various information related to the operation of the processor (202). For example, memory (204) may store software code containing instructions for performing some or all of the processes controlled by the processor (202) or for performing the descriptions, functions, procedures, proposals, methods, and / or sequences of operations disclosed in this document. Here, the processor (202) and memory (204) may be part of a communication modem / circuit / chip designed to implement wireless communication technology. A transceiver (206) may be connected to the processor (202) and may transmit and / or receive wireless signals through at least one antenna (208). The transceiver (206) may include a transmitter and / or receiver. The transceiver (206) may be interchangeable with a radio frequency (RF) unit. In this disclosure, a wireless device may mean a communication modem / circuit / chip.

[0067] Hereinafter, hardware elements of the wireless device (200) will be described in more detail. Although not limited thereto, at least one protocol layer may be implemented by at least one processor (202). For example, at least one processor (202) may implement at least one layer (e.g., functional layers such as PHY (physical), MAC (media access control), RLC (radio link control), PDCP (packet data convergence protocol), RRC (radio resource control), and SDAP (service data adaptation protocol). At least one processor (202) may generate at least one PDU (Protocol Data Unit) and / or at least one SDU (service data unit) according to the descriptions, functions, procedures, proposals, methods and / or operation sequences disclosed in this document. At least one processor (202) may generate messages, control information, data, or information according to the descriptions, functions, procedures, proposals, methods and / or operation sequences disclosed in this document. At least one processor (202) may generate a signal (e.g., a baseband signal) including a PDU, SDU, message, control information, data, or information according to the functions, procedures, proposals, and / or methods disclosed in this document and provide it to at least one transceiver (206). At least one processor (202) may receive a signal (e.g., a baseband signal) from at least one transceiver (206) and may obtain a PDU, SDU, message, control information, data, or information according to the descriptions, functions, procedures, proposals, methods, and / or operation sequences disclosed in this document.

[0068] At least one processor (202) may be referred to as a controller, microcontroller, microprocessor, or microcomputer. At least one processor (202) may be implemented by hardware, firmware, software, or a combination thereof. For example, at least one application-specific integrated circuit (ASIC), at least one digital signal processor (DSP), at least one digital signal processing device (DSPD), at least one programmable logic device (PLD), or at least one field programmable gate array (FPGA) may be included in at least one processor (202). The descriptions, functions, procedures, proposals, methods, and / or operation sequences disclosed in this document may be implemented using firmware or software, and the firmware or software may be implemented to include modules, procedures, functions, etc. Firmware or software configured to perform the descriptions, functions, procedures, proposals, methods, and / or operation sequences disclosed in this document may be included in at least one processor (202) or stored in at least one memory (204) and driven by at least one processor (202). The descriptions, functions, procedures, proposals, methods, and / or flowcharts disclosed in this document may be implemented using firmware or software in the form of code, instructions, and / or sets of instructions.

[0069] At least one memory (204) may be connected to at least one processor (202) and may store various forms of data, signals, messages, information, programs, codes, instructions, and / or commands. At least one memory (204) may be composed of ROM (read-only memory), RAM (random access memory), EPROM (erasable programmable read-only memory), flash memory, hard drive, registers, cache memory, computer read storage media, and / or combinations thereof. At least one memory (204) may be located inside and / or outside of at least one processor (202). Additionally, at least one memory (204) may be connected to at least one processor (202) via various technologies, such as wired or wireless connections.

[0070] At least one transceiver (206) may transmit user data, control information, wireless signals / channels, etc., as mentioned in the methods and / or operation flowcharts, etc. of this document to at least one other device. At least one transceiver (206) may receive user data, control information, wireless signals / channels, etc., as mentioned in the descriptions, functions, procedures, proposals, methods and / or operation flowcharts, etc. disclosed in this document from at least one other device. For example, at least one transceiver (206) may be connected to at least one processor (202) and may transmit and receive wireless signals. For example, at least one processor (202) may control at least one transceiver (206) to transmit user data, control information, or wireless signals to at least one other device. Additionally, at least one processor (202) may control at least one transceiver (206) to receive user data, control information, or wireless signals from at least one other device. Additionally, at least one transceiver (206) may be connected to at least one antenna (208), and at least one transceiver (206) may be configured to transmit and receive user data, control information, wireless signals / channels, etc., as described in the descriptions, functions, procedures, proposals, methods, and / or operation sequence diagrams disclosed in this document through at least one antenna (208). In this document, at least one antenna may be a plurality of physical antennas or a plurality of logical antennas (e.g., antenna ports). At least one transceiver (206) may convert the received 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 at least one processor (202).At least one transceiver (206) can convert user data, control information, wireless signals / channels, etc. processed using at least one processor (202) from a baseband signal to an RF band signal. To this end, at least one transceiver (206) may include an (analog) oscillator and / or filter.

[0071] The components of the wireless device described with reference to FIG. 3 may be referred to by other terms in terms of their function. For example, the processor (202) may be referred to as the control unit, the transceiver (206) as the communication unit, and the memory (204) as the storage unit. In some cases, the communication unit may be used to mean at least a part of the processor (202) and the transceiver (206).

[0072] The structure of the wireless device described with reference to FIG. 3 can be understood as the structure of at least part of various devices. For example, the structure of the wireless device illustrated in FIG. 3 may be at least part of the various devices described with reference to FIG. 2 (e.g., robot (110a), vehicle (110b-1, 110b-2), XR device (110c), portable device (110d), home appliance (110e), IoT device (110f), AI device / server (110g)). Furthermore, according to various embodiments, the device may include other components in addition to the components illustrated in FIG. 3.

[0073] For example, the device may be a portable device such as a smartphone, smartpad, wearable device (e.g., smart watch, smart glasses), or portable computer (e.g., laptop, etc.). In this case, the device may further include at least one of a power supply unit that supplies power and includes a wired / wireless charging circuit, a battery, etc., an interface unit that includes at least one port for connection with another device (e.g., an audio input / output port, a video input / output port), and an input / output unit for inputting and outputting video information / signals, audio information / signals, data, and / or information input by a user.

[0074] For example, the device may be a mobile device such as a mobile robot, vehicle, train, manned / unmanned aerial vehicle (AV), or ship. In this case, the device may further include at least one of a drive unit comprising at least one of an engine, motor, power train, wheel, brake, and steering device of the device; a power supply unit that supplies power and includes a wired / wireless charging circuit, battery, etc.; a sensor unit that senses state information, environmental information, and user information of the device or its surroundings; an autonomous driving unit that performs functions such as path maintenance, speed control, and destination setting; and a position measurement unit that acquires position information of the moving body through a GPS (global positioning system) and various sensors.

[0075] For example, the device may be an XR device such as an HMD, a HUD (head-up display) equipped in a vehicle, a television, a smartphone, a computer, a wearable device, a home appliance, digital signage, a vehicle, a robot, etc. In this case, the device may further include at least one of a power supply unit that supplies power and includes a wired / wireless charging circuit, a battery, etc., an input / output unit that acquires control information, data, etc. from the outside and outputs a generated XR object, and a sensor unit that senses state information, environment information, and user information of the device or the surroundings of the device.

[0076] For example, the device may be a robot that can be classified into industrial, medical, household, military, etc., depending on the purpose or field of use. In this case, the device may further include at least one of a sensor unit that senses state information, environmental information, and user information of the device or its surroundings, and a drive unit that performs various physical actions, such as moving robot joints.

[0077] For example, the device may be an AI device such as a TV, projector, smartphone, PC, laptop, digital broadcasting terminal, tablet PC, wearable device, set-top box (STB), radio, washing machine, refrigerator, digital signage, robot, vehicle, etc. In this case, the device may further include at least one of an input unit that acquires various types of data from the outside, an output unit that generates output related to sight, hearing, or touch, a sensor unit that senses state information, environmental information, and user information of the device or its surroundings, and a training unit that learns a model composed of an artificial neural network using training data.

[0078] The structure of the wireless device illustrated in FIG. 3 may be understood as part of a terminal (or first node), or part of an intermediate point, or part of a base station (or second node). If the device illustrated in FIG. 3 is a base station (or second node), the device may further include a wired transceiver for front haul and / or back haul communication. If the front haul and / or back haul communication is based on wireless communication, at least one transceiver (206) illustrated in FIG. 3 is used for front haul and / or back haul communication, and a wired transceiver may not be included.

[0079] Communication procedures

[0080] FIG. 4 illustrates an exemplary communication procedure between a first node and a second node to which some examples of the present disclosure may be applied.

[0081] FIG. 4 illustrates the operation of a first node (110) (e.g., a terminal) and a second node (120) (e.g., a base station) transmitting and / or receiving data, and the operation performed prior to this.

[0082] In step S101, the first node (110) and the second node (120) can perform synchronization. For example, the terminal (110) performs an initial cell search operation. Specifically, the terminal (110) can detect at least one synchronization signal transmitted from the base station (120) according to a predefined rule. Here, the synchronization signal may include a plurality of synchronization signals (e.g., a primary synchronization signal, a secondary synchronization signal) classified according to structure or use. Through this, the terminal (110) can identify the boundaries of the frame, subframe, slot, and / or symbol of the base station (120) and obtain information about the base station (120) (e.g., a cell identifier).

[0083] In step S103, the first node (110) can obtain system information transmitted from the second node (120). For example, the system information is information related to the attributes, characteristics, and / or capabilities of the base station (120) required to connect to the base station (120) and use the service, and can be classified according to content (e.g., whether it is essential for connection), transmission structure (e.g., the channel used, whether it is provided on-demand), etc., and can be classified, for example, into a master information block (MIB) and a system information block (SIB). If necessary, the terminal (110) may transmit a signal requesting system information prior to receiving the system information. Such request and provision of system information may be performed after a random access procedure described later.

[0084] In step S105, the first node (110) and the second node (120) can perform a random access procedure. For example, the terminal (110) can transmit and / or receive at least one message for a random access procedure (e.g., a random access preamble, a RAR (random access response) message, etc.) based on information related to the random access channel of the base station (120) obtained through system information (e.g., channel location, channel structure, structure of a supported preamble, etc.). For example, the terminal (110) may transmit a preamble (e.g., message 1 (MSG1)) through a random access channel, receive a random access response (RAR) message (e.g., message 2 (MSG2)), transmit a message (e.g., message 3 (MSG3)) containing information related to the terminal (110) (e.g., identification information) to the base station (120) using scheduling information included in the RAR message, and receive a message (e.g., message 4 (MSG4)) for contention resolution and / or connection establishment. As another example, MSG1 and MSG3 may be transmitted and received as a single message (e.g., message A (MSG A), or MSG2 and MSG4 may be transmitted and received as a single message (e.g., message B (MSG B).

[0085] In step S107, the first node (110) and the second node (120) can perform signaling of control information. For example, the control information may be defined in various layers, such as a layer that controls the connection (e.g., a radio resource control (RRC) layer), a layer that handles mapping between logical channels and transmission channels (e.g., a media access control (MAC) layer), and a layer that handles physical channels (e.g., a physical (PHY) layer). For example, the terminal (110) and the base station (120) may perform at least one of signaling to establish a connection, signaling to determine settings related to communication, and signaling to indicate allocated resources.

[0086] In step S109, the first node (110) and the second node (120) can transmit and / or receive data. For example, the terminal (110) and the base station (120) can process data based on the signaling of control information and transmit and / or receive data. For example, when transmitting data, the terminal (110) or the base station (120) can perform at least one of channel encoding, rate matching, scrambling, constellation mapping, layer mapping, waveform modulation, antenna mapping, and resource mapping on the information bits. For example, when receiving data, the terminal (110) or the base station (120) can perform at least one of extracting a signal from a resource, antenna-specific waveform demodulation, signal placement considering layer mapping, constellation demapping, descrambling, and channel decoding.

[0087] 6G System Core Technology

[0088] As core implementation technologies for 6G systems, technologies such as artificial intelligence (AI), THz (Terahertz) communication, optical wireless technology, free space optics (FSO) backhaul network, multiple input multiple output (MIMO) technology, blockchain, 3D networking, quantum communication, unmanned aerial vehicles, cell-free communication, wireless information and energy transfer (WIET), integration of sensing and communication, integration of access backhaul networks, holographic beamforming, big data analysis, and large intelligent surface (LIS) can be adopted.

[0089] artificial intelligence

[0090] The introduction of AI into communications can streamline and enhance real-time data transmission. AI can determine how complex target tasks are performed using numerous analyses. AI can increase efficiency and reduce processing latency. Time-consuming tasks such as handover, network selection, and resource scheduling can be performed instantly using AI. AI can also play a significant role in machine-to-machine (M2M), machine-to-human, and human-to-machine communication. Furthermore, AI can enable rapid communication in Brain-Computer Interfaces (BCI). 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.

[0091] FIG. 5 illustrates an exemplary functional framework for AI operations to which some examples of the present disclosure may be applied.

[0092] Below, to provide a more specific explanation of AI (or AI / ML (machine learning)), terms can be defined as follows.

[0093] - Data collection: Data collected from network nodes, management entities, or terminals, serving as a basis for AI model training, data analysis, and inference.

[0094] - AI model: A data-driven algorithm that applies AI technology to generate a set of outputs containing predictive information and / or decision parameters based on a set of inputs.

[0095] - AI / ML Training: An online or offline process of training an AI model by learning features and patterns that best represent data and acquire an AI / ML model trained for inference.

[0096] - AI / ML Inference: A process of making predictions or deriving decisions based on collected data and an AI model using a trained AI model.

[0097] Referring to FIG. 5, the data collection function (10) is a function that collects input data and provides processed input data to the model training function (20) and the model inference function (30).

[0098] Examples of input data may include measurements from terminals or other network entities, feedback from actors, and outputs from AI models.

[0099] The data collection function (10) performs data preparation based on input data and provides the input data processed through data preparation. Here, the data collection function (10) does not perform specific data preparation (e.g., data pre-processing and cleaning, forming and transformation) for each AI algorithm, and can perform data preparation common to AI algorithms.

[0100] After the data preparation process is performed, the data collection function (10) can provide training data (11) to the model training function (20) and provide inference data (12) to the model inference function (30). Here, the training data (11) corresponds to data required as input for the AI ​​model training function (20), and the inference data (12) corresponds to data required as input for the AI ​​model inference function (30).

[0101] The data collection function (10) may be performed by a single entity (e.g., terminal, RAN node, network node, etc.) but may also be performed by multiple entities. In this case, training data (11) and inference data (12) from multiple entities may be provided to the model training function (20) and the model inference function (30), respectively.

[0102] The model training function (20) may correspond to a function that performs AI model training, validation, and testing, which can generate model performance metrics as part of the AI ​​model testing procedure. If necessary, the model training function (20) may also be responsible for data preparation (e.g., data pre-processing and cleaning, formatting and transformation, etc.) based on training data (11) provided by the data collection function (10).

[0103] Here, model deployment / update (13) can be used to initially deploy a trained, validated, and tested AI model to the model inference function (30) or to provide an updated model to the model inference function (30).

[0104] The model inference function (30) may correspond to a function that provides an AI model inference output (16) (e.g., a prediction or a decision). The model inference function (30) may provide model performance feedback (14) to the model training function (20) where applicable. Additionally, the model inference function (30) may be responsible for data preparation (e.g., data pre-processing and cleaning, formatting and transformation, etc.) based on the inference data (12) provided by the data collection function (10) if necessary.

[0105] Here, output (16) refers to the inference output of an AI model generated by the model inference function (30), and the details of the inference output may vary depending on the use case.

[0106] Model performance feedback (14) can be used to monitor the performance of the AI ​​model if available, and this feedback may be omitted.

[0107] The actor function (40) is a function that receives an output (16) from the model inference function (30) and triggers or performs a corresponding operation / action. The actor function (40) can trigger an operation / action on another entity (e.g., one or more terminals, one or more RAN nodes, one or more network nodes, etc.) or on itself.

[0108] Feedback (15) can be used to derive training data (11) and inference data (12), or to monitor the performance of the AI ​​model, the impact on the network, etc.

[0109] Meanwhile, the definitions of training, validation, and testing in data sets used in AI / ML can be distinguished as follows.

[0110] - Training data: Refers to the dataset used to train a model.

[0111] - Validation data: This refers to a dataset used to validate a model that has already been trained. Validation data typically refers to a dataset used to prevent overfitting of the training dataset. Additionally, validation data can refer to a dataset used to select the best model among the various models trained during the learning process. Therefore, validation can be viewed as a type of training.

[0112] - Test data: Refers to the dataset for final evaluation. This data is unrelated to training.

[0113] For example, within the entire dataset, training data and validation data can be divided in a ratio of approximately 8:2 or 7:3. Alternatively, within the entire dataset, training data:validation data:test data can be divided in a ratio of 6:2:2.

[0114] Depending on whether the base station and the terminal possess the capability for AI / ML functions, the cooperation level can be defined as follows, and variations resulting from the combination of multiple levels below or the separation of any one level are also possible.

[0115] Category 0a: This corresponds to a no collaboration framework. In this case, the AI / ML algorithm is based on pure implementation and may not require changes to the wireless interface.

[0116] Category 0b: Corresponds to a framework that involves a wireless interface modified to fit efficient implementation-based AI / ML algorithms but lacks cooperation.

[0117] Category 1: This applies to cases involving inter-node support to improve the AI / ML algorithms of each node. For example, it applies when a terminal receives support from a base station (for training, adaptation, etc.), and vice versa. At this level, model exchange between network nodes is not required.

[0118] Category 2: This applies to cases where joint ML operations between a terminal and a base station can be performed. This level requires AI / ML model commands or exchanges between network nodes.

[0119] The functions exemplified in Figure 5 above may be implemented at RAN nodes (e.g., base station, TRP, base station CU, etc.), network nodes, network operator's OAM (operation administration maintenance), or terminals.

[0120] Alternatively, two or more entities among a RAN, a network node, a network operator's OAM, or a terminal may cooperate to implement the functions exemplified in FIG. 5. For example, one entity may perform some of the functions of FIG. 5, and another entity may perform the remaining functions. As such, some of the functions exemplified in FIG. 5 are performed by a single entity (e.g., a terminal, a RAN node, a network node, etc.), the transmission / provision of data / information between each function may be omitted. For example, if the model training function (20) and the model inference function (30) are performed by the same entity, the transmission / provision of model distribution / update (13) and model performance feedback (14) may be omitted.

[0121] Alternatively, any one of the functions exemplified in FIG. 5 may be performed by two or more entities among the RAN, network node, network operator's OAM, or terminal in collaboration. This may be referred to as a split AI operation.

[0122] FIG. 6 illustrates an example of operations related to AI model training and AI model inference to which some examples of the present disclosure may be applied.

[0123] For example, the AI ​​model training function can be performed by network nodes (e.g., core network nodes, network operator's OAM, etc.), and the AI ​​model inference function can be performed by RAN nodes (e.g., base station, TRP, base station's CU, etc.).

[0124] Step 1: RAN Node 1 and RAN Node 2 can transmit input data (e.g., training data) for training an AI model to a network node. Here, RAN Node 1 and RAN Node 2 can also transmit data collected from terminals to the network node (e.g., terminal measurements related to RSRP (reference signal received power), RSRQ (reference signal received quality), and SINR (signal to interference-plus-noise ratio) of the serving cell and neighboring cells, terminal location, speed, etc.).

[0125] Step 2: Network nodes can train AI models using the received training data.

[0126] Step 3: The network node can distribute / update the AI ​​model to RAN Node 1 and / or RAN Node 2. RAN Node 1 (and / or RAN Node 2) may also continue model training based on the received AI model.

[0127] For the sake of convenience of explanation, it is assumed that the AI ​​model was deployed / updated only to RAN Node 1.

[0128] Step 4: RAN Node 1 can receive input data (e.g., inference data) for AI model inference from the terminal and RAN Node 2.

[0129] Step 5: RAN Node 1 can perform AI model inference using the received inference data to generate output data (e.g., prediction or decision).

[0130] Step 6: If applicable, RAN node 1 can send model performance feedback to network nodes.

[0131] Step 7: RAN Node 1, RAN Node 2, and the terminal (or 'RAN Node 1 and the terminal', or 'RAN Node 1 and RAN Node 2') can perform an action based on the output data. For example, in the case of a load balancing action, the terminal may move from RAN Node 1 to RAN Node 2.

[0132] Step 8: RAN Node 1 and RAN Node 2 can transmit feedback information to network nodes.

[0133] FIG. 7 illustrates another example of operations related to AI model training and AI model inference to which some examples of the present disclosure may be applied.

[0134] For example, both AI model training and AI model inference functions can be performed by RAN nodes (e.g., base station, TRP, base station's CU, etc.).

[0135] Step 1: The terminal and RAN node 2 can transmit input data (e.g., training data) for training an AI model to RAN node 1.

[0136] Step 2: RAN Node 1 can train an AI model using the received training data.

[0137] Step 3: RAN Node 1 can receive input data (e.g., inference data) for AI model inference from the terminal and RAN Node 2.

[0138] Step 4: RAN Node 1 can perform AI model inference using the received inference data to generate output data (e.g., prediction or decision).

[0139] Step 5: RAN Node 1, RAN Node 2, and the terminal (or 'RAN Node 1 and the terminal', or 'RAN Node 1 and RAN Node 2') can perform an action based on the output data. For example, in the case of a load balancing action, the terminal may move from RAN Node 1 to RAN Node 2.

[0140] Step 6: RAN Node 2 can send feedback information to RAN Node 1.

[0141] FIG. 8 illustrates another example of operations related to AI model training and AI model inference to which some examples of the present disclosure may be applied.

[0142] For example, the AI ​​model training function may be performed by a RAN node (e.g., base station, TRP, base station CU, etc.), and the AI ​​model inference function may be performed by a terminal.

[0143] Step 1: A terminal can transmit input data (e.g., training data) for training an AI model to a RAN node. Here, the RAN node can collect data (e.g., terminal measurements related to RSRP, RSRQ, SINR of the serving cell and neighboring cells, terminal location, velocity, etc.) from various terminals and / or other RAN nodes.

[0144] Step 2: The RAN node can train an AI model using the received training data.

[0145] Step 3: The RAN node can distribute / update the AI ​​model to the terminal. The terminal may also continue model training based on the received AI model.

[0146] Step 4: Input data (e.g., inference data) for AI model inference can be received from terminals and RAN nodes (and / or other terminals).

[0147] Step 5: The terminal can perform AI model inference using the received inference data to generate output data (e.g., prediction or decision).

[0148] Step 6: If applicable, the terminal can transmit model performance feedback to the RAN node.

[0149] Step 7: The terminal and the RAN node can perform actions based on the output data.

[0150] Step 8: The terminal can transmit feedback information to the RAN node.

[0151] THz communication

[0152] Data transmission rates can be increased by expanding bandwidth. This can be achieved by using sub-THz communication with wide bandwidth and applying advanced large-scale MIMO technology. THz waves, also known as sub-millimeter radiation, 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–300 GHz band range (sub-THz band) is considered the primary portion of the THz band for cellular communication. Adding the sub-THz band to the mmWave band increases 6G cellular communication capacity. Among the defined THz bands, the 300 GHz–3 THz band is located in the far-infrared (IR) frequency band. Although the 300 GHz–3 THz band is part of the broadband, it lies at the boundary of the broadband and immediately following the RF band. Therefore, this 300 GHz–3 THz band exhibits similarities to RF.

[0153] FIG. 9 shows an electromagnetic spectrum to which some examples of the present disclosure may be applied.

[0154] Key characteristics of THz communication include (i) widely available bandwidth to support very high data transmission rates, and (ii) high path loss occurring at high frequencies (highly directional antennas are indispensable). The narrow beam width generated by highly directional antennas reduces interference. The small wavelength of THz signals allows a much larger number of antenna elements to be integrated into devices and BSs operating in this band. This enables the use of advanced adaptive array technologies that can overcome range limitations.

[0155] When transmitting system information (e.g., MIB) of a cell in the THz frequency band, it can be inefficient because, in the case of high frequency bands, beam sweeping must be performed more frequently to cover the entire area of ​​the cell as the beam width becomes narrower. In particular, transmitting system information using this method is even more inefficient when there are not many users in the cell.

[0156] FIG. 10 illustrates an exemplary system information transmission / reception procedure to which some examples of the present disclosure may be applied.

[0157] The example of FIG. 10 is applicable not only to THz communication environments but also to 6G communication environments where THz communication is not applied. In addition, the procedure exemplified in FIG. 10 can be combined with various embodiments of the present disclosure described below. For example, embodiments described below can be performed based on system information obtained by the procedure exemplified in FIG. 10.

[0158] In step S1010, the second node (120) (e.g., a base station) can transmit system information of cell #1 through cell #2. For example, the base station provides at least two cells, cell #1 uses a THz frequency band, and cell #2 uses a frequency band other than the THz frequency band. Here, the system information may include at least one of a system frame number (SFN) generated at a higher layer, a PDCCH configuration for SIB1, cell barring, cell re-selection, and subcarrier spacing, and may include at least one of a synchronization signal / PBCH (physical broadcast channel) block index generated at a physical layer. To this end, as an example, cell #1 and cell #2 may have a secondary cell and primary cell relationship.

[0159] In step S1030, the first node (110) (e.g., a terminal) can acquire synchronization for cell #1. Synchronization can be acquired by detecting a synchronization signal. Generally, synchronization is acquired prior to receiving system information, but since the system information of cell #1 is received in cell #2, the acquisition of synchronization for cell #1 can be performed after receiving system information. For example, the terminal can acquire synchronization based on system information. Alternatively, the acquisition of synchronization may be performed prior to step S1010.

[0160] In step S1050, the first node (110) may transmit a signal to connect to cell #1. For example, the signal may include a random access preamble. The structure of such a signal and the resource for transmitting the signal (e.g., a channel) may be identified through system information. Subsequently, in step S1070, the first node (110) and the second node (120) may perform a connection procedure to cell #1 and perform communication.

[0161] The procedure described with reference to FIG. 10 may be performed when the first node (110) first connects to cell #1 of the second node (120). Alternatively, a similar procedure may be performed when the first node (110) handovers to cell #1 of the second node (120). However, in the case of a handover, the system information of cell #1 may be received from a cell of a different base station other than cell #2 of the second node (120).

[0162] Communication in the THz band is expected to experience severe path loss, and to overcome this, terminals and base stations may be required to use very sharp beams. The use of sharp beams implies that terminals and base stations must perform beam control in addition to beamforming, meaning that a very large number of beams are utilized. Consequently, aligning the transmit and receive beams between the base station and the terminal takes a very long time. Furthermore, if the beam alignment between the base station and the terminal is disrupted due to the movement of the terminal, time is frequently required to realign the beams, which may lead to link instability.

[0163] FIG. 11 illustrates an exemplary beam management procedure to which some examples of the present disclosure may be applied.

[0164] Figure 11 illustrates an example of a procedure for searching and / or selecting beams for THz communication, but this procedure is not limited to a THz environment and can also be applied in a 6G communication environment where THz communication is not applied.

[0165] Here, "beam" can be interpreted as other terms having equivalent technical meanings capable of distinguishing beams, such as "spatial domain filter," "spatial domain transmit filter," "spatial domain receive filter," reference signal (RS) resources for distinguishing beams, and SSB index.

[0166] In step S1110, the second node (120) (e.g., base station) may set resources for beam management to the first node (110) (e.g., terminal). Here, the resources may include at least one of time-frequency resources, channels, and spatial resources (e.g., antenna ports). For example, the base station may utilize a beam search signal (BSS) that is transmitted spatially separated from the existing downlink signal / channel for beam search. Here, the BSS may be transmitted based on a dedicated port for beam search. The dedicated port may be a port different from the port used for transmitting the existing downlink signal / channel (e.g., SSB, PDSCH (physical downlink shared channel), etc.). BSS is a term defined for convenience of explanation, and the technical concept according to the present embodiment is not limited to the term BSS itself. For example, a signal transmitted based on a dedicated port defined / set for beam search may be included in the technical concept according to the present embodiment.

[0167] In step S1130, the second node (120) (e.g., a base station) transmits measurement signals using multiple transmission beams. For example, the measurement signals may include at least one of a reference signal and a synchronization signal. At this time, the measurement signals may be transmitted as many times as the number of beams requiring measurement, and may be transmitted using a multi-beam transmission method that forms multiple beams simultaneously to reduce sweeping time. Here, multi-beam transmission may be performed based on at least one of a multi-panel, a sub-array, or a true time delay (TTD).

[0168] In step S1050, the first node (110) (e.g., a terminal) may transmit a feedback signal to the second node (120) (e.g., a base station). The feedback signal may indicate at least one beam selected by the terminal. The terminal may select at least one preferred beam based on the measurement signals received in step S1030.

[0169] In step S1070, the first node (110) and the second node (120) can perform communication. For example, the second node (120) can perform transmission to the first node (110) using the receiving beam of the first node (110) selected in step S1050. If channel reciprocity is established, the transmission beam of the first node (110) can also be determined through steps S1030 and S1050, so the transmission operation from the first node (110) can also be performed using a beam that has a reciprocity relationship with the beam selected in step S1050. If channel reciprocity is not established, a procedure including the transmission of measurement signal(s) by the first node (110) and the transmission of feedback signal(s) by the second node (120) may be performed first to determine the transmission beam of the first node (110).

[0170] Non-terrestrial networks (NTN)

[0171] FIGS. 12 and FIGS. 13 show examples of NTN scenarios to which some examples of the present disclosure may be applied.

[0172] NTN can represent a network or network segment that uses RF (radio frequency) resources mounted on a satellite (or UAS (unmanned aerial system) platform).

[0173] Figure 12 shows an example of a typical scenario of an NTN based on a transparent payload, and Figure 13 shows an example of a typical scenario of an NTN based on a regenerative payload.

[0174] Referring to FIG. 12, the satellite (or UAS platform) can establish a service link with a terminal. The satellite (or UAS platform) can be connected to a gateway via a feeder link. The satellite can be connected to a data network via the gateway. A beam footprint may refer to an area where signals transmitted by the satellite can be received.

[0175] Referring to FIG. 13, a satellite (or UAS platform) can establish a service link with a terminal. The satellite (or UAS platform) connected to the terminal can be connected to another satellite (or UAS platform) via inter-satellite links (ISL). Another satellite (or UAS platform) can be connected to a gateway via a feeder link. Based on a regenerated payload, the satellite can be connected to a data network via another satellite and a gateway. If no ISL exists between the satellite and another satellite, a feeder link between the satellite and the gateway may be required.

[0176] FIGS. 12 and 13 are merely examples of NTN scenarios, and NTN can be implemented based on various scenarios. For example, a satellite (or UAS platform) can implement a transparent or regenerative (with on-board processing) payload. For example, a satellite (or UAS platform) can generate multiple beams across a designated service area depending on the field of view of the satellite (or UAS platform). For example, the field of view of the satellite (or UAS platform) may vary depending on the on-board antenna diagram and the minimum elevation angle.

[0177] For example, the transparent payload may include radio frequency filtering, frequency conversion, and amplification. Therefore, the waveform signal repeated by the payload may not be altered.

[0178] For example, the regeneration payload may include radio frequency filtering, frequency conversion and amplification, demodulation / decoding, switching and / or routing, and coding / modulation. For example, the regeneration payload may be substantially the same as carrying all or part of the base station functions on a satellite (or UAS platform).

[0179] Integrated Sensing and Communication (ISAC)

[0180] Wireless sensing is a technology that utilizes radio frequencies to determine the instantaneous linear velocity, angle, distance (or range) of an object, thereby obtaining information about the characteristics of the environment and / or objects within that environment. Since radio frequency sensing capabilities do not require connecting to objects via devices within a network, they can provide services for determining object locations without the need for devices. The ability to obtain range, velocity, and angle information from radio frequency signals can provide a wide range of new functions, such as various object detection and recognition (e.g., vehicles, humans, animals, UAVs), as well as high-precision localization, tracking, and activity recognition. Wireless sensing services can provide information to various industries (e.g., unmanned aerial vehicles, smart homes, V2X, factories, railways, public safety, etc.) that enable applications such as intruder detection, assisted vehicle steering and navigation, trajectory tracking, collision avoidance, traffic management, and health and traffic management. In some cases, wireless sensing may utilize non-3GPP type sensors (e.g., radar, cameras) to further support 3GPP-based sensing. For example, the operation of a wireless sensing service, such as sensing operations, may depend on the transmission, reflection, and scattering processing of wireless sensing signals. Therefore, wireless sensing can provide an opportunity to enhance existing communication systems from communication networks to wireless communication and sensing networks.

[0181] FIG. 14 shows examples of sensing operations to which some examples of the present disclosure may be applied.

[0182] Specifically, FIG. 14(a) illustrates an example of monostatic sensing operation using a sensing receiver and a sensing transmitter located at the same position. FIG. 14(b) illustrates an example of bistatic sensing operation using a sensing receiver and a sensing transmitter located at separate positions. A sensing receiver receives a signal that is reflected or scattered by a sensing object from a sensing signal transmitted from a sensing transmitter, and can extract or acquire sensing data based on the received signal. A sensing result can be generated or determined through appropriate processing of this sensing data. The sensing result can be provided to a trusted third-party entity or service outside the 3GPP system via an entity or service within the 3GPP system.

[0183] Method for indicating / transmitting a PDCCH that supports higher-order modulation

[0184] In a basic wireless communication system, a terminal can receive a PDCCH modulated with QPSK (Quadrature Phase Shift Keying) from a base station. In this case, only 2 bits of information per RE (resource element) can be transmitted in the QPSK-modulated PDCCH. Accordingly, depending on the CORESET setting instructed / set by the base station, a latency problem related to the QPSK-modulated PDCCH may occur.

[0185] In describing the present disclosure, CORESET may include a set of resources defined to enable a control channel, such as a PDCCH, to be transmitted within a physically allocated / directed / set time and frequency domain.

[0186] In next-generation wireless communication systems, for services where latency issues are critical (e.g., URLLC), base stations can flexibly instruct / set / transmit PDCCHs modulated in 8-PSK (Phase Shift Keying) or 16-QAM (Quadrature Amplitude Modulation) to terminals. To support services such as XR as well as addressing latency issues, PDCCHs modulated with a higher order can improve efficiency by lowering the code rate of the same resources. Additionally, in scenarios such as multi-carrier scheduling and UL simultaneous scheduling where relatively high DCI sizes (e.g., DCI of 1000 bits or more) are used, PDCCHs modulated with a higher order can improve resource and latency efficiency.

[0187] The following describes a method for indicating / setting a high-order modulation PDCCH that can be used in various use cases or scenarios. Although this disclosure is described based on a specific system (e.g., NR), it does not specify or limit the transmission and reception forms of certain systems unless otherwise stated. It is obvious that the methods proposed in this disclosure can be applied to the structures and services of all wireless communication transmission and reception, provided that the principles of the invention are not infringed, even without further explanation. In describing this disclosure, " / " may mean "and," "or," or "and / or," and Ambient IoT refers to AmIoT.

[0188] FIG. 15 is a flowchart for explaining the operation of a terminal according to one embodiment of the present disclosure.

[0189] The terminal can receive configuration information from the base station that includes first information related to a physical downlink control channel (PDCCH) candidate for each aggregation level (AL) (S1510).

[0190] For example, the above configuration information may be related to a search space (SS) (set), but is not limited thereto. The above configuration information may be transmitted from a base station to a terminal via upper layer signaling (e.g., RRC messages, SIBs, system information, etc.).

[0191] For example, the first information may include the number of PDCCH candidates per AL. AL may be 1, 2, 4, 8 or / and 16, but is not limited thereto. AL may also be set / defined to a value of 16 or greater.

[0192] Additionally or alternatively, the configuration information may include the type of a first modulation order (MO) for at least one first CCE among a plurality of control channel elements (CCEs) per AL. Furthermore, the configuration information may include the type of a second MO for at least one second CCE among a plurality of CCEs per AL. In this case, the type of the first MO and the type of the second MO may be the same or different.

[0193] That is, the terminal can set / instruct the type of MO for multiple CCEs per AL from the base station, and the type of MO for each of the multiple CCEs may be the same or different.

[0194] For example, each of the type of the first MO and the type of the second MO may be at least one of QPSK (Quadrature Phase Shift Keying), 8-PSK (phase shift keying), 16-QAM (Quadrature Amplitude Modulation), 64 QAM, or 256 QAM, but is not limited thereto.

[0195] For example, based on the fact that the type of the first MO and the type of the second MO are different from each other, the ratio of the number of at least one first CCE associated with the type of the first MO and the number of at least one second CCE associated with the type of the second MO may be predefined or set by the base station. That is, when multiple CCEs are composed of CCEs to which different MOs are applied, the ratio of the number of CCEs by MO type may be predefined or set by the base station. For example, the ratio of the number of CCEs by MO type may be included in the setting information, but is not limited thereto.

[0196] Additionally or alternatively, based on the fact that the type of the first MO and the type of the second MO are different from each other, the index of the first CCE may be even and the index of the second CCE may be odd. In this case, the ratio of the number of at least one first CCE associated with the type of the first MO and the number of at least one second CCE associated with the type of the second MO may be 1:1.

[0197] Additionally or alternatively, the configuration information may include a demodulation reference signal (DMRS) density associated with at least one PDCCH candidate (for example, a candidate for a PDCCH configured based on a plurality of CCEs associated with the configuration information). That is, the terminal may explicitly receive a DMRS density for at least one PDCCH candidate from the base station. For example, the terminal may receive information from the base station for setting an index of a DMRS density value corresponding to at least one PDCCH candidate among a plurality of DMRS density candidate values.

[0198] As another example of the present disclosure, DMRS density values ​​may be determined / indicated / defined / set according to the MO type of at least one PDCCH candidate (or, a CCE constituting the PDCCH candidate). For example, at least one first CCE to which a first MO is applied may be associated with a first DMRS density value, and at least one second CCE to which a second MO is applied may be associated with a second DMRS density value. That is, a first DMRS density value may be set / defined for a first MO, and a second DMRS density value may be set / defined for a second MO.

[0199] For example, based on the fact that the type of the first MO is higher than the type of the second MO, the first DMRS density value may be higher or lower than the second DMRS density value. That is, if the modulation order corresponding to the first MO is higher than the modulation order corresponding to the second MO, the first DMRS density value may be higher or lower than the second DMRS density value.

[0200] As described above, the first information, the type of the first MO for at least one of the multiple CCEs per AL, and information related to DMRS density may be transmitted to the terminal through the same configuration information, but are not limited thereto. The first information, the type of the first MO for at least one of the multiple CCEs per AL, and information related to DMRS density, etc., may also be transmitted to the terminal through different configuration information.

[0201] The terminal can monitor at least one PDCCH candidate based on the first information (S1520).

[0202] Specifically, at least one PDCCH candidate can be configured based on a plurality of CCEs configured by configuration information. Based on the number of PDCCH candidates being configured per AL and at least one PDCCH candidate being configured based on CCEs, the terminal can monitor at least one PDCCH candidate. The terminal can perform a PDCCH reception operation by monitoring at least one PDCCH candidate. That is, the terminal can perform a PDCCH reception operation based on at least one PDCCH candidate.

[0203] And, the maximum number of at least one PDCCH candidate may be the number of PDCCH candidates per AL. For example, when the number of PDCCH candidates is set to 4 when the AL value is 2 according to the configuration information (e.g., the first information), the maximum value of the number of at least one PDCCH candidate to be monitored by the terminal may be 4.

[0204] In describing with reference to FIG. 15, the configuration information may set / indicate the type of MO in units of CCE, but is not limited thereto. The configuration information may set the type of MO in units of RE, REG, or CCE groups associated with at least one PDCCH candidate. Within the description above, the first / second CCE may be replaced with the first / second RE / REG / CCE groups.

[0205] The method described in the example of FIG. 15 can be performed by the device (200) of FIG. 3. That is, the terminal of FIG. 15 can be implemented as the device (200) of FIG. 3. For example, one or more processors (202) of the device (200) of FIG. 15 can receive configuration information containing first information related to an AL-specific PDCCH candidate from a base station through one or more transceivers (206). One or more processors (202) can monitor at least one PDCCH candidate based on the first information.

[0206] Furthermore, one or more memories (204) of the device (200) may store instructions for performing the method described in the example of FIG. 15 or the examples described below when executed by one or more processors (202).

[0207] FIG. 16 is a flowchart for explaining the operation of a base station according to one embodiment of the present disclosure.

[0208] The base station can transmit configuration information containing first information related to a PDCCH candidate for each AL to the terminal (S1610).

[0209] For example, a base station may transmit configuration information to a terminal through upper layer signaling, and the configuration information may include first information related to a PDCCH candidate per AL and / or the type of a first / second MO for at least one first / second CCE among a plurality of CCEs per AL.

[0210] That is, the configuration information may set / indicate the type of MO in units of CCEs, but is not limited thereto. The configuration information may set the type of MO in units of RE, REG, or CCE groups associated with at least one PDCCH candidate. That is, within the description above, the first / second CCEs may be replaced with the first / second RE / REG / CCE groups.

[0211] Additionally or alternatively, the rules by which MO is set / directed for the 1st / 2nd CCE may be predefined.

[0212] The base station can transmit the PDCCH to the terminal through at least one PDCCH candidate based on the first information (S1620).

[0213] For example, a base station may transmit at least one PDCCH candidate configured by configuration information (e.g., first information, etc.) to a terminal, and the terminal may monitor at least one candidate PDCCH.

[0214] The method described in the example of FIG. 16 may be performed by a specific device. One or more processors of the specific device may transmit configuration information containing first information related to an AL-specific PDCCH candidate to a terminal via one or more transceivers. One or more processors may transmit a PDCCH to a terminal via one or more transceivers through at least one PDCCH candidate based on the first information.

[0215] Furthermore, one or more memories of a specific device may store instructions for performing the method described in the example of FIG. 16 or the examples described below when executed by one or more processors.

[0216] Below, we will explain how to specify / set MOs for each CCE within a CORESET and how to specify / set mixed MOs (modulation orders) in a single CCE.

[0217] Example 1

[0218] Example 1 relates to a method for indicating / setting MOs for each CCE within a CORESET.

[0219] As described above, in a basic wireless communication system, scheduling of channels such as PDSCH, PUCCH (physical uplink control channel), and PUSCH (physical uplink shared channel) can be performed / assigned by transmitting and receiving a PDCCH modulated with QPSK. A problem exists in that a PDCCH modulated with QPSK can transmit 2 bits per 1 RE unit, and consequently, only a small amount of information can be transmitted. For example, since a PDCCH modulated with QPSK is composed of single modulation, the SE (Spectral Efficiency) can be determined by the code rate, which can be significantly restrictive in various scenarios.

[0220] Example 1-1

[0221] In one embodiment of the present disclosure, to solve the problem described above, a method may be applied in which MO is individually indicated / set by a base station for CCE(s) existing within a CORESET indicated / set for a terminal in an improved wireless communication system.

[0222] The terminal may set / instruct MO for the CCE(s) existing within the CORESET according to the method described below:

[0223] Method 1: A method for directing / setting PDCCH candidates so that the MOs of the CCEs constituting the AL (aggregation level) are not mixed; and

[0224] Method 2: A method for directing / setting PDCCH candidates so that MOs among CCEs constituting AL are mixed.

[0225] In addition, Method 2 may include a method of configuring the AL through a certain ratio of CCEs constituting the AL to indicate / set an MO for a PC (PDCCH candidate) indicated / set (hereinafter, Method 2-1), and a method of indicating / set a specific MO for a CCE indicated / set in the AL according to the MO indicated / set for a CCE constituting the AL (hereinafter, Method 2-2).

[0226] Specifically, the terminal can receive CORESET configuration information from the base station. That is, when the terminal is instructed / configured with a CORESET from the base station, it can be instructed / configured with the time and frequency resources of the CORESET through the "duration" and "frequencyDomainResources" parameters included in the CORESET configuration. Once the time and frequency resources of the CORESET are instructed / configured, instructions / configurations for the CCE(s) existing within the corresponding CORESET can be made, and the number of CCEs constituting the PC may vary depending on the AL being instructed / configured.

[0227] In a basic wireless communication system, the AL indicated / set / defined can be 1, 2, 4, 8, or 16. It is assumed that the MO is indicated / set for each CCE according to the method described above. When the AL is 1, the PC is configured using one CCE, so a situation in which MOs are mixed among the CCEs constituting the PC may not occur. However, when the AL is 2 or more, the PC is configured using two or more CCEs, so a situation in which MOs among the CCEs constituting a single PC are mixed may occur.

[0228] Example 1-1 relates to a method in which MO is individually indicated / set by a base station for CCE(s) existing within a CORESET in order to solve the problem described above.

[0229] As described above, in a basic wireless communication system, the AL indicated / set / defined is 1, 2, 4, 8, or 16, and when the AL is 1, the PC is configured using 1 CCE, so a situation in which MOs are mixed for each CCE configuring the PC may not occur. When the method(s) for indicating / setting MOs individually for the CCE(s) existing within the CORESERT described in Example 1-1 are applied, a high MO (e.g., 16 QAM) may be set for a specific subset (e.g., K) of the total N CCEs (indexes) configured within a single CORESET, and a low MO (e.g., QPSK) may be set for the remaining (e.g., NK=L) CCEs (indexes).

[0230] In this case, the index(s) of the K CCE(s) with high MO are always fixed or can be determined based on the value (e.g., time) of a specific time index (e.g., at least one of frame, subframe, slot, or symbol index).

[0231] Method 1

[0232] Method 1 relates to a method for indicating / setting a PC such that the MOs of the CCEs constituting the AL are not mixed. Specifically, when Method 1 is applied, the CCEs capable of constituting the AL can be indicated / set as a PC composed of a single MO. Specifically, a starting CCE index can be determined using a hashing function on a basic wireless communication system, and candidate PC(s) can be configured based on the starting CCE index. In this case, the candidate PCs can be indicated / set by being composed only of CCEs with identical MOs.

[0233] For example, if AL is 4 and the CCE index value starting with the hashing function is K, the indicated / set PCs may be indicated / set as CCE#K, CCE#K+1, CCE#K+2, CCE#K+3, and the terminal may perform blind decoding (BD) on the PCs. For example, the terminal may sequentially perform BD on the number of indicated / set PCs per AL according to the set of search spaces.

[0234] Specifically, as described above, a starting CCE index can be determined through a hashing function, and candidate PC(s) can be configured based on the starting CCE index. The terminal is the first M among the candidate PC(s) composed only of CCEs with the same MO. i (M > M i (in the case of) one or M (M < M i (in the case where) can be determined as the final BD target, and BD can be performed on the final BD target. At this time, M i represents the number of PCs specified / set for each AL.

[0235] Accordingly, when Method 1 is applied, the base station may indicate / set only a single (or identical) MO for the CCEs constituting the PC. The base station and / or terminal may modulate / demodulate the PDCCH through a single MO for all CCEs. For example, with respect to a PC where AL is set to 4, CCE#K, CCE#K+1, CCE#K+2, and CCE#K+3 may be modulated at the base station with a single MO (e.g., QPSK, 8-PSK, 16 QAM, or 256 QAM), and the terminal may likewise perform demodulation based on the MO for the corresponding CCE(s) according to a pre-indicated / set or predefined rule.

[0236] For example, a terminal can receive instructions / configurations for MOs individually or by CCE group for CCEs existing within a CORESET that have been indicated / configured through upper layer signaling (e.g., RRC signaling or SIB).

[0237] Additionally or alternatively, a low (or high) MO may be indicated / set for half of the CCEs existing within the indicated / set CORESET (e.g., half of the CCEs to which a low CCE index is set / mapped), and a high (or low) MO may be indicated / set for the remaining half of the CCEs (e.g., half of the CCEs to which a high CCE index is set / mapped). The terminal and the base station may perform PDCCH transmission and reception according to the predefined rules described above. As described above, the index of the CCE to which the high MO or low MO is applied may be changed / determined over time based on the value of a specific time index (e.g., at least one of a frame, subframe, slot, or symbol index).

[0238] Additionally or alternatively, MOs may be set / indicated through a randomization function for each individual CCE or group of CCEs. The ratio of the number of CCEs in which different MOs are indicated / indicated may be set by the base station or determined according to a predefined rule (e.g., the ratio of CCEs with different MOs according to the number of CCEs). In describing the present disclosure, the low MO may be indicated / indicated as QPSK, and the high MO may be indicated / indicated as 8-QAM, 8-PSK, 16QAM, or 256 QAM, but is not limited thereto.

[0239] As an example of the present disclosure, FIG. 17(a) is a drawing for explaining a method of configuring a PC through a CCE in which the same MO is indicated / set as method 1 is applied. That is, FIG. 17(a) is an example for explaining a method of configuring a PC so that the MOs of the CCE are not mixed (e.g., an example in which AL is set / indicated to 2).

[0240] If the MO of the CCE(s) is indicated / set according to the method described above, a PC can be configured with the same CCE(s) as the MO according to the AL indicated / set by the base station. According to the AL, the CCE index can be sequentially increased, and the starting CCE index can be indicated / set through a hashing function. To configure a PC with the same CCE(s) according to the AL, the same MO can be indicated / set from the starting CCE index up to the CCE index forming the indicated / set AL.

[0241] Therefore, we assume a case where MO is directed / set by CCE group (e.g., a high (or low) MO is applied to half of the low CCE indices, and a low (or high) MO is applied to the remaining half of the high CCE indices). In this case, the CORESET can be directed / set by the base station through a parameter within the hashing function that distinguishes the MO, so that the CCEs can be composed of the same MO from the starting CCE index up to the number of CCEs capable of constituting the AL that can be directed / set.

[0242] In this case, the CCE group (or the number of CCEs within the CCE group, etc.) may be greater than the minimum AL that can be indicated / set (e.g., 16). The hashing function according to the method described above is used to construct a PC for an AL indicated / set across all CCEs in a basic wireless communication system, but in an improved wireless communication system where a higher MO can be indicated / set (as in Method 1), the hashing function may be based on a CCE with the same MO indicated / set. In this case, the hashing function used in the basic wireless communication system may be used for each CCE group with different MOs.

[0243] Method 2

[0244] Method 2 relates to a method for indicating / setting a PDCCH candidate by indicating / setting a mixed MO among CCE(s) constituting an AL. Specifically, Method 2 relates to a method for configuring a PC through CCEs with different MOs according to an AL indicated / set by a base station. As described above, Method 2 may include a method for configuring a PC having a constant code rate by maintaining the ratio of CCEs having different MOs constituting the AL (e.g., Method 2-1), and a method for configuring a PC by indicating / setting a specific MO for CCEs constituting the indicated / set AL (e.g., CCEs with different MOs indicated / set) (e.g., Method 2-2).

[0245] As an example of the present disclosure, a method for constructing a PC by maintaining a constant ratio of CCEs having different MOs constituting an AL (e.g., 2-1) can be constructed by applying a constant rule to CCEs composed of CCE indices that increase sequentially according to AL, thereby enabling the PC to maintain a constant code rate.

[0246] Specifically, when the PC is configured according to Method 2-1, the starting CCE index can be determined using a hashing function as in Method 1, and M based on the starting CCE index i (Number of PCs specified / set for each AL) PC(s) may be configured. In this case, PCs that can be configured differently from Method 1 may include CCE(s) with different MOs.

[0247] The above-mentioned fixed rule may include a rule for directing / setting MOs by CCE index such that the MO types of the CCEs constituting AL have a fixed ratio (e.g., 1:1). For example, among the CCEs included in CORESET, a high (or low) MO may be directed / set / applied to CCEs with even indices, and a low (or high) MO may be directed / set / applied to CCEs with odd indices.

[0248] As described above, in a basic wireless communication system, an AL set / indicated as 1, 2, 4, 8, or 16 may be indicated, and if a CCE is defined according to the rules described above, a PC with a constant code rate may be configured. The above example relates to the case where a PC is configured in a 1:1 ratio (per MO), but regardless of the ratio, a high MO (e.g., 8-PSK, 16QAM, 256 QAM) or a low MO (e.g., QPSK) may be indicated / set for each CCE index according to the rules described above.

[0249] For example, FIG. 17(b) is a diagram illustrating a method of configuring a PC based on CCEs indicated / set with different MOs according to method 2-1 when AL is set to 2. That is, a PC can be configured with CCEs indicated / set with different MOs, and CCEs indicated / set with different MOs can have a certain ratio.

[0250] A method for configuring a PC by indicating / setting a specific MO for CCEs constituting an indicated / set AL (e.g., CCEs with different MOs indicated / set) (e.g., Method 2-2) relates to a method of indicating a specific MO for the CCE(s) constituting the AL. That is, unlike Method 2-1, which uses the MO indicated / set for each CCE as is by setting the base station, Method 2-2 relates to a method of indicating / setting a specific MO (e.g., average value of the MO of the configured CCE, the lowest MO among the configured CCEs, the highest MO among the configured CCEs) for the CCEs constituting the AL according to the MO of the CCEs constituting the indicated / set AL.

[0251] Specifically, when Method 2-2 is applied as in Method 1 and Method 2-1, the starting CCE index is determined through a hashing function, and M according to the starting CCE index i (Number of PCs specified / set for each AL) PCs may be configured. Method 2-2 may include a method for determining that PCs composed of CCEs with different MOs are unified to a specific MO (e.g., a low MO or a high MO).

[0252] For example, assume a case where CCEs with different MOs that constitute AL (e.g., 4) indicate / set PCs in a constant ratio (e.g., 1:1). If there are two CCEs with MOs indicated / set by QPSK (e.g., 2-bit transmission) and two CCEs with MOs indicated / set by 16 QAM (e.g., 4-bit transmission), the MO of the CCEs can be indicated / set by the average value of the MOs of the configured CCEs (e.g., 8-PSK or 8-QAM (e.g., MOs that transmit 3 bits)), and the base station and the terminal can transmit and receive PCs composed of the CCEs.

[0253] An example has been described in which a specific MO is defined through the average MO value of CCEs set / directed by the base station, but this is not limited thereto. A specific MO may be defined as the lowest MO (e.g., QPSK) or the highest MO (e.g., 16 QAM) among the CCEs set / directed by the base station.

[0254] For example, as shown in Fig. 17 (c), the average value of CCEs indicated / set to different MOs according to method 2-2 (when AL value is 2) can be defined as a specific MO, and PC can be indicated / set according to the specific MO value.

[0255] When the method(s) described in Example 1-1 are applied, channel estimation performance may not be maintained in the case of a "Wideband DMRS" that assumes the same precoding for all REGs (resource element groups) within a CORESET where MOs differ by CCE.

[0256] In a basic wireless communication system, precoding granularity can be maintained for REG bundles or all consecutive RBs. However, if precoding granularity is maintained for all consecutive RBs within a CORESET where MOs differ by CCE, the complexity of channel estimation may increase or performance may decrease from the terminal's perspective.

[0257] Therefore, if a situation arises where CORESETs with different MOs are indicated / set for each CCE through the methods described above, the problem can be resolved by applying precoding fineness to units where CRBs are in a continuous range within the CORESET, or to units of CCEs where the same MO is indicated / set.

[0258] As an example of the present disclosure, CCEs with low MO and CCEs with high MO may be separated, and CCE indexing may be performed on each, after which a hashing function may be applied for each MO. The base station may [apply] to a specific M with high MO. high PCs and a specific M with low MO low By selecting PCs, a total of M i (M i = M high + M low You can configure ) PCs.

[0259] Examples 1-2

[0260] Examples 1-2 relate to a method for adjusting MO and / or DMRS density (e.g., the ratio of DMRS existing within 1 REG (Resource element group)). That is, while Example 1-1 relates to a method for indicating / setting high / low MO for specific units (e.g., CCE), Example 1-2 relates to a method for indicating / setting DMRS density to flexibly adjust not only MO but also to increase resource efficiency of PDCCH transmission and reception.

[0261] In a basic wireless communication system, a constant DMRS density can be set / maintained. In an improved wireless communication system, the DMRS density can be flexibly indicated / set to increase the resource efficiency of PDCCH transmission and reception. Therefore, not only the method of setting / indicating MO according to Example 1-1 but also the method of indicating / setting DMRS density can be applied.

[0262] For example, in Method 1, a starting CCE index is determined using a hashing function, and candidate PC(s) can be constructed based on the starting CCE index. Then, PC(s) composed only of CCEs with the same MO can be determined as the final BD target. In this case, PC(s) can be constructed only of CCE(s) with the same DMRS density, rather than CCEs with the same MO, and then those CCE(s) can be determined as the final BD target. As in Methods 2-1 and 2-2, CCE(s) can be constructed based on MO, but PC(s) can also be determined by constructing CCE(s) with a low DMRS density (e.g., 1 / 6) or a high DMRS density (1 / 2).

[0263] In addition, as described above, PDCCH can be transmitted and received as MO or DMRS densities are indicated or set by the base station, thereby increasing resource efficiency. When PDCCH is transmitted and received as both MO and DMRS densities are indicated or set by the base station, not only high resource efficiency but also flexibility can be increased.

[0264] The following describes how MO and / or DMRS densities are indicated / set by the base station.

[0265] In a basic wireless communication system, PDCCHs are transmitted and received using a single modulation scheme (e.g., QPSK), and DMRS density can be constant at a specific value (e.g., 1 / 4). That is, three REs (e.g., RE #1, #5, #9) within one REG can be used for DMRS allocation. However, in an improved wireless communication system, high MO PDCCHs can be transmitted and received through the methods described above, and DMRS density can be determined differently depending on the base station settings or the indicated / set MO. Methods 3 and 4 can be applied as methods for indicating / setting DMRS density to a terminal.

[0266] Method 3

[0267] Method 3 relates to a method for explicitly indicating / setting DMRS density through upper layer signaling (e.g., RRC signaling, SIB, etc.). That is, DMRS density in the PDCCH transmitted to the terminal can be determined / indicated / set according to the configuration and / or judgment of the base station.

[0268] For example, when the channel is good (e.g., when the channel quality value exceeds a threshold) or when smooth channel estimation is required, the base station may set / instruct a high MO for the CCE(s). Accordingly, the base station may set / instruct a low (or high) DMRS density for the terminal. In describing the present disclosure, it is assumed that the low DMRS density is 1 / 4 or less and the high DMRS density is greater than 1 / 4, but is not limited thereto.

[0269] For example, a specific DMRS density value can be indicated / set by the base station indicating / setting the index value of a predefined table (e.g., Table 1) associated with DMRS density candidates (e.g., 1 / 4, 1 / 2) to the terminal.

[0270] Index DMRS Density 01 / 211 / 321 / 431 / 6

[0271] As another example, the base station can transmit information to the terminal that directly indicates / sets the DMRS density value.

[0272] Method 4

[0273] Method 4 relates to a method in which a predefined DMRS density is implicitly indicated / set according to an MO indicated / set by a base station. That is, a predefined DMRS density may be indicated / set for a base station and / or terminal according to an MO indicated / set per CCE.

[0274] Specifically, in an environment where the channel is good (or where channel estimation needs to be smooth), a high MO may be indicated / set for the CCE(s), and accordingly, the DMRS density may be set to a low value (or a high value). For example, if the MO indicated / set for CCE #0 is 16 QAM, a low DMRS density (e.g., 1 / 6) (or a high DMRS density) (e.g., 1 / 2) (corresponding to that MO) may be applied to CCE #0. Accordingly, performance improvement in terms of resource efficiency (or detection operation) may be achieved.

[0275] Example 2

[0276] Example 2 relates to a method for indicating / setting mixed MOs in a single CCE. Unlike Example 1, which relates to a method for indicating / setting MOs by CCE or group of CCEs, Example 2 relates to a method for indicating / setting mixed MOs within a single CCE.

[0277] In a basic wireless communication system, a single CCE may include a total of 6 REGs (e.g., a total of 72 REs). DMRS symbols may be mapped to 18 of the 72 REs, and PDCCH symbols may be mapped to specific REs among the remaining 54 REs.

[0278] Example 2 describes a method for mapping a symbol with a high MO indicated / set to a specific RE among 54 REs with data mapped within a single CCE. A symbol with a high MO indicated / set to an RE constituting a single CCE may be mapped according to at least one of the options described below:

[0279] Option 1: Method to map high MO symbols to REs adjacent to DMRS;

[0280] Option 2: Method for mapping high MO symbols to REs located between DMRSs existing within a REG; and

[0281] Option 3: A method for mapping high MO symbols to REs located between DMRSs existing within a bundled REG.

[0282] Below, the operation and parameters for each option will be explained in detail.

[0283] Option 1

[0284] Option 1 relates to a method for mapping high MO symbols to REs adjacent to REs mapped by DMRS. As an example of the present disclosure, as illustrated in FIG. 18(a), when Option 1 is applied, high MO symbols may be mapped to RE#(0,2), RE#(4,6), and RE#(8,10) adjacent to RE#1, RE#5, and RE#9 mapped by DMRS.

[0285] In a basic wireless communication system, channel estimation using DMRS can be performed, and for REs where DMRS does not exist, channel estimation can be performed through interpolation between DMRSs. Therefore, channel estimation can be performed more smoothly for REs adjacent to DMRS compared to REs further away. Accordingly, when Option 1 is applied, high MO symbols can be mapped to REs adjacent to the RE where DMRS is mapped. In this case, low MO may refer to QPSK used in a basic wireless communication system, and high MO may include 8-PSK, 8-QAM, 16 QAM, 64 QAM, etc., which have an MO higher than QPSK.

[0286] Option 2

[0287] Option 2 concerns a method for mapping high MO symbols to REs located between DMRSs within a REG. In other words, Option 2 utilizes the principle that channel estimation performance can be relatively better for REs adjacent to DMRSs (e.g., REs located between DMRSs) compared to REs located at the outer boundary within a REG. Accordingly, high MO symbols can be mapped to REs located between DMRSs.

[0288] As an example of the present disclosure, FIG. 18(b) is a diagram illustrating a method for mapping high MO symbols through Option 2. As shown in FIG. 18(b), low MO symbols (e.g., QPSK, etc.) may be mapped to outer boundaries within a REG (e.g., REG #0 and REG #10 and #11), and high MO symbols (e.g., 8-PSK, 8-QAM, 16-QAM, 64-QAM, etc.) may be mapped to REs located between DMRS.

[0289] Option 3

[0290] Option 3 is about a method for mapping high MO symbols to REs located between DMRSs existing within a bundled REG.

[0291] Unlike Method 2, Method 3 is not limited to within the REG and relates to a method for mapping high MO symbols to REs located between DMRSs in REG bundling units. As an example of the present disclosure, as illustrated in FIG. 19, the structure of the REG bundle may vary depending on the time duration of the CORESET, and the REs located between DMRSs may also be configured differently. Accordingly, as illustrated in FIG. 19, the RE to which the high MO symbol is mapped when the REG bundle is composed of one OFDM symbol may be different from the RE to which the high MO symbol is mapped when the REG bundle is composed of two or three OFDM symbols.

[0292] For example, FIG. 19 (a) and (b) illustrate the case where the REG bundle size is 2, and FIG. 19 (b) illustrates the case where a mapping method such as Option 2 is applied. That is, when the REG bundle is composed of 2 or 3 OFDM symbols, high MO symbols can be mapped to RE such as Option 2.

[0293] Example 3

[0294] Example 3 relates to a method of reducing the power of a resource indicated / set to a low MO and increasing the power of a resource indicated / set to a high MO.

[0295] In basic wireless communication systems, channel encoding can be performed using polar coding when generating a PDCCH. Due to the characteristics of polar coding, 2 n A number of bits can be defined as a mother polar code, and if the number of bits that can be mapped according to the combination of RE and MO is smaller than the mother polar code, a puncturing operation can be performed.

[0296] Therefore, if a PDCCH is generated using only QPSK according to the options described above (e.g., Option 1, Option 2 and / or Option 3) or a combination of options, a PDCCH can be generated so that no puncturing occurs.

[0297] For example, as described above, PDCCH symbols can be mapped to only 54 of the 72 REs constituting a single CCE. In this case, if 44 QPSK REs and 10 16 QAM REs are mapped, a total of 128 bits can be transmitted. Therefore, PDCCH transmission and reception operations between the base station and the terminal can be performed without puncturing the mother polar code. Similarly, in a situation where "AL=2" (e.g., a total of 2 CCEs), if 88 QPSK REs and 20 16 QAM REs are mapped, 256 bits can be transmitted.

[0298] When the method according to Example 1 (and / or a detailed example of Example 1) and Example 2 is applied, in which different MOs are indicated / set within a CCE / CCE group to indicate / set the PDCCH, the power of the resource indicated / set to a high MO can be increased through the method according to Example 3. That is, more power can be allocated to the resource indicated / set to a high MO in order to increase the channel reliability associated with the CCE / RE indicated / set to a high MO more than the channel reliability associated with the CCE / RE indicated / set to a low MO.

[0299] A method for reducing the power of a resource indicated / set to a low MO and increasing the power of a resource indicated / set to a high MO relates to a method of additionally allocating a portion of the power assigned to a resource indicated / set to a low MO symbol, which is less sensitive to channel reliability than a high MO symbol, to a resource indicated / set to a high MO symbol.

[0300] For example, a resource indicated / set to a low MO of QPSK can transmit 2 bits per RE, and a resource indicated / set to a high MO of 16 QAM can transmit 4 bits per RE. In this case, the resource indicated / set to a high MO may transmit a larger number of bits (e.g., twice as many) compared to the resource indicated / set to a low MO. Therefore, power allocation for RE within 1 OFDM symbol can be performed according to the number of bits transmitted relative to the resource based on the indicated / set MO.

[0301] For example, power allocation can be performed as shown in Equation 1. In Equation 1, P high represents the power allocated to the RE indicated / set to a high MO, and P OFDM_sym represents the power allocated to 1 OFDM symbol, and bit high represents the number of bits that can be mapped to a symbol indicated / set by a high MO, and bit low represents the number of bits that can be mapped to a symbol indicated / set by the low MO, and RE high represents the number of REs indicated / set with a high MO, and RE low can mean the number of REs indicated / set to a low MO.

[0302] [Mathematical Formula 1]

[0303]

[0304] For example, Equation 1 is about the power allocated to RE indicated / set to a high MO per 1 RE, and through the above method, the power allocated to RE indicated / set to a low MO per 1 RE can also be calculated.

[0305] In communication between a base station and a terminal, the power per OFDM symbol is maintained constant, so it may not be possible to allocate additional power to CCEs mapped to one or more OFDM symbols by allocating power from other OFDM symbols. As described above, power allocation for REs within one OFDM symbol may be possible.

[0306] As described above, performing power allocation is merely one example, and power allocation for resources (e.g., CCE, RE) indicated / set by different MOs existing within 1 OFDM can be set / indicated through the base station's upper layer signaling (e.g., RRC signaling or SIB). As another example, power allocation for resources indicated / set by different MOs can be performed according to predefined rules.

[0307] In addition, the methods described in Example 1 (and / or detailed examples of Example 1) and Example 2 may be performed based on a PDCCH structure (e.g., CORESET, CCE) used in a basic wireless communication system. However, this is merely one example, and the methods described above (e.g., a method for indicating / setting a high MO for a PDCCH) may also be applied to a PDCCH structure that may be defined in a next-generation communication system.

[0308] For example, in Example 1 (and / or a detailed example of Example 1), a method of indicating / setting different MOs for each CCE within a CORESET was described, but MOs can also be indicated / set in units other than CCEs (e.g., REG, REG bundle) through the same method. Likewise, REGs or REG bundles with high MOs (e.g., indices) may always be fixed or may change based on the value of a specific time index (e.g., at least one of a frame, subframe, slot, or symbol index).

[0309] According to the various embodiments described above, the transmission of PDCCH can be performed through high MO symbol mapping, thereby utilizing resources more efficiently and reducing latency.

[0310] Methods, embodiments, or descriptions for implementing the method proposed in this disclosure may each be applied separately, or one or more methods (or embodiments or descriptions) may be applied in combination.

[0311] The embodiments described above are combinations of the components and features of the present disclosure in a specific form. Each component or feature should be considered optional unless otherwise explicitly stated. Each component or feature may be implemented in a form not combined with other components or features. Additionally, it is possible to construct embodiments of the present disclosure by combining some components and / or features. The order of operations described in the embodiments of the present disclosure 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. It is obvious that embodiments may be constructed by combining claims that are not explicitly related in the claims, or that they may be included as new claims by amendment after filing.

[0312] It is obvious to those skilled in the art that the present disclosure may be embodied in other specific forms without departing from the essential features of the present disclosure. Accordingly, the detailed description set forth above should not be interpreted restrictively in all respects and should be considered exemplary. The scope of the present disclosure shall be determined by a reasonable interpretation of the appended claims, and all modifications within the equivalent scope of the present disclosure are included within the scope of the present disclosure.

[0313] The scope of the present disclosure includes software or machine-executable instructions (e.g., operating systems, applications, firmware, programs, etc.) that enable operations according to the methods of various embodiments to be executed on a device or computer, and a non-transitory computer-readable medium on which such software or instructions, etc. are stored and executable on a device or computer. Instructions that may be used to program a processing system to perform the features described in the present disclosure may be stored on or within a storage medium or a computer-readable storage medium, and the features described in the present disclosure may be implemented using a computer program product comprising such a storage medium. The storage medium may include, but is not limited to, high-speed random access memory such as DRAM, SRAM, DDR RAM, or other random access solid-state memory devices, and may include non-volatile memory such as one or more magnetic disk storage devices, optical disk storage devices, flash memory devices, or other non-volatile solid-state storage devices. The memory may optionally include one or more storage devices located remotely from the processor(s). Memory or alternatively, non-volatile memory device(s) within memory comprises a non-transient computer-readable storage medium. The features described in this disclosure may be stored in any one of the machine-readable media and integrated into software and / or firmware that can control the hardware of a processing system and allow the processing system to interact with other mechanisms utilizing results according to the embodiments of this disclosure. Such software or firmware may include, but is not limited to, application code, device drivers, operating systems, and execution environments / containers.

[0314] Here, the wireless communication technology implemented in the device (100, 200) of the present disclosure may include LTE, NR, and 6G, as well as Narrowband Internet of Things for low-power communication. In this case, for example, NB-IoT technology may be an example of LPWAN (Low Power Wide Area Network) technology and may be implemented according to standards such as LTE Cat NB1 and / or LTE Cat NB2, but is not limited to the names mentioned above. Additionally or generally, the wireless communication technology implemented in the device (100, 200) of the present disclosure may perform communication based on LTE-M technology. In this case, for example, LTE-M technology may be an example of LPWAN technology and may be referred to by various names such as eMTC (enhanced Machine Type Communication). For example, LTE-M technology may be implemented in 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 names mentioned above. Additionally or generally, wireless communication technology implemented in the device (100, 200) of the present disclosure may include at least one of ZigBee, Bluetooth, and Low Power Wide Area Network (LPWAN) for low-power communication, and is not limited to the names mentioned above. As an example, ZigBee technology may create personal area networks (PANs) related to small / low-power digital communication based on various standards such as IEEE 802.15.4, and may be referred to by various names.

[0315] Although the method proposed in this disclosure has been described with an example applied to 3GPP LTE / LTE-A and 5G systems, it can be applied to various wireless communication systems in addition to 3GPP LTE / LTE-A and 5G systems.

Claims

1. A step of receiving configuration information containing first information related to a physical downlink control channel (PDCCH) candidate by aggregation level (AL) from a base station by a terminal; and The method includes the step of monitoring at least one PDCCH candidate by the terminal based on the first information above, and The above setting information includes the type of a first modulation order (MO) for at least one first CCE among a plurality of control channel elements (CCEs) for each AL.

2. In Paragraph 1, The first information above includes the number of PDCCH candidates for each AL, and The maximum number of at least one PDCCH candidate is the number of PDCCH candidates per AL, in the method.

3. In Paragraph 1, A method in which at least one PDCCH candidate is established based on the plurality of CCEs.

4. In Paragraph 1, The above setting information includes the type of a second MO for at least one second CCE among the plurality of CCEs for each AL, and The above-mentioned type of the first MO and the above-mentioned type of the second MO are the same or different, method.

5. In Paragraph 4, A method in which each of the type of the first MO and the type of the second MO is at least one of QPSK (Quadrature Phase Shift Keying), 8-PSK (phase shift keying), 16-QAM (Quadrature Amplitude Modulation), 64 QAM, or 256 QAM.

6. In Paragraph 5, Based on the fact that the type of the first MO and the type of the second MO are different from each other: A method in which the ratio of the number of at least one first CCE associated with the type of the first MO and the number of at least one second CCE associated with the type of the second MO is predetermined or set by the base station.

7. In Paragraph 5, A method in which the index of at least one first CCE is even and the index of at least one second CCE is odd.

8. In Paragraph 1, A method in which at least one PDCCH candidate is established based on the plurality of CCEs.

9. In Paragraph 1, A method in which the above setting information includes a demodulation reference signal (DMRS) density associated with at least one PDCCH candidate.

10. In Paragraph 4, The above at least one first CCE is related to the first DMRS density value, and The above at least one second CCE is a method associated with a second DMRS density value.

11. In Paragraph 10, A method in which, based on the fact that the type of the first MO is higher than the type of the second MO, the first DMRS density value is higher or lower than the second DMRS density value.

12. One or more transceivers; and It includes one or more processors connected to the above one or more transmitters and receivers, and The above one or more processors are: Receive configuration information containing first information related to a physical downlink control channel (PDCCH) candidate by aggregation level (AL) from a base station through one or more transceivers; and Based on the above first information, it is configured to monitor at least one PDCCH candidate, and The above setting information includes a type of first modulation order (MO) for at least one first CCE among a plurality of control channel elements (CCEs) for each AL, a terminal.

13. A step of transmitting configuration information containing first information related to a physical downlink control channel (PDCCH) candidate by aggregation level (AL) to a terminal by a base station; and The method includes the step of transmitting a PDCCH to the terminal by the base station through at least one PDCCH candidate based on the first information above. The above setting information includes the type of a first modulation order (MO) for at least one first CCE among a plurality of control channel elements (CCEs) for each AL.

14. In a base station, the above base station is: One or more transceivers; and It includes one or more processors connected to the above one or more transmitters and receivers, and The above one or more processors are: Transmitting configuration information containing first information related to a physical downlink control channel (PDCCH) candidate by aggregation level (AL) to a terminal via the one or more transceivers; and It is configured to transmit a PDCCH to the terminal through the one or more transceivers via at least one PDCCH candidate based on the first information above, and The above setting information includes a base station, wherein the type of a first modulation order (MO) for at least one first CCE among a plurality of control channel elements (CCEs) for each AL.

15. In a processing device configured to control a terminal, the processing device comprises: One or more processors; and A processing device comprising one or more computer memories that are operably connected to one or more processors and store instructions for performing a method according to any one of claims 1 to 11 based on execution by one or more processors.

16. One or more non-transitory computer-readable media storing one or more instructions, A computer-readable medium in which one or more of the above instructions are executed by one or more processors to control a device to perform a method according to any one of claims 1 to 11.

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