Method and apparatus for device-to-device communication in wireless communication system

Abstract

Disclosed are a method and an apparatus for device-to-device communication in a wireless communication system. A method according to an embodiment of the present disclosure may comprise the steps of: transmitting, by a first device, a first transmission to a second device; and receiving, by the first device, a second transmission from the second device in response to the first transmission.

Description

Method and device for device-to-device communication in a wireless communication system

[0001] The present disclosure relates to a wireless communication system, and more particularly, to a method and device for communication between devices in a wireless communication system.

[0002] The fifth generation (5G) wireless communication system, the successor to 4G LTE (long-term evolution), is a new, clean-slate mobile communication system characterized by high performance, low latency, and high availability. 5G NR (New Radio) can utilize all available spectrum resources, from low-frequency bands below 1 GHz, to intermediate-frequency bands between 1 GHz and 10 GHz, and to high-frequency (or millimeter wave) bands above 24 GHz. 6G wireless communication systems are being developed based on the underlying technologies of 5G wireless communication.

[0003] The 6G wireless communication system is being developed with the goals 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 Internet of Things (IoT) devices, (vi) ultra-reliable connectivity, and (vii) connected intelligence with machine learning capabilities. The vision of the 6G system can be divided into four aspects: intelligent connectivity, deep connectivity, holographic connectivity, and ubiquitous connectivity. Considering the requirements of the 6G system, such as a peak data rate of 1 Tbps per device, an end-to-end latency of 1 ms, 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, various technologies are being researched.

[0004] The technical problem of the present disclosure is to provide a method and device for device-to-device communication in a wireless communication system supporting the ambient internet of things (A-IoT).

[0005] In addition, an additional technical challenge of the present disclosure is to provide a method and device for transmitting and receiving signals / messages for random access or inventory rounds in a wireless communication system supporting A-IoT.

[0006] The technical problems to be achieved in the present disclosure are not limited to the technical problems mentioned above, and other technical problems not mentioned can be clearly understood by a person having ordinary skill in the technical field to which the present disclosure belongs from the description below.

[0007] A method according to an aspect of the present disclosure may include: transmitting, by a first device, a first transmission to a second device; and receiving, by the first device, a second transmission from the second device in response to the first transmission. A plurality of different transmissions including the first transmission are transmitted to the second device from a plurality of devices including the first device, and the second transmission may include information related to the first device among the plurality of devices.

[0008] A method according to an additional aspect of the present disclosure may include: receiving, by a second device, a plurality of different transmissions from a plurality of devices including a first device, the plurality of transmissions including a first transmission by the first device; and transmitting, by the second device, a second transmission to the first device in response to the first transmission. The second transmission may include information related to the first device among the plurality of devices.

[0009] According to an embodiment of the present disclosure, when random access is performed between multiple devices in a wireless communication system supporting A-IoT, transmission and reception between devices can be performed smoothly by preventing problems such as overlapping or collision of transmission and reception between devices from occurring.

[0010] According to an embodiment of the present disclosure, an inventory round can be smoothly performed between multiple devices in a wireless communication system supporting A-IoT.

[0011] The effects that can be obtained from the present disclosure are not limited to the effects mentioned above, and other effects that are not mentioned will be clearly understood by a person having ordinary skill in the art to which the present disclosure pertains from the description below.

[0012] The accompanying drawings, which are incorporated in and are part of the detailed description to aid in understanding the present disclosure, provide embodiments of the present disclosure and, together with the detailed description, describe the technical features of the present disclosure.

[0013] Figure 1 illustrates a flexible network topology to which some examples of the present disclosure may be applied.

[0014] FIG. 2 illustrates an example of a communication system to which some examples of the present disclosure may be applied.

[0015] FIG. 3 illustrates an example of a wireless device to which some examples of the present disclosure may be applied.

[0016] FIG. 4 exemplarily illustrates a communication procedure between a first node and a second node to which some examples of the present disclosure may be applied.

[0017] FIG. 5 exemplarily illustrates a functional framework for AI / ML operations to which some examples of the present disclosure may be applied.

[0018] FIG. 6 illustrates an example of a communication procedure based on an AI / ML model between a first node and a second node to which some examples of the present disclosure may be applied.

[0019] FIG. 7 illustrates an electromagnetic spectrum to which some examples of the present disclosure may be applied.

[0020] FIG. 8 exemplarily illustrates a system information transmission / reception procedure to which some examples of the present disclosure may be applied.

[0021] FIG. 9 illustrates an exemplary beam management procedure to which some examples of the present disclosure may be applied.

[0022] Figure 10 illustrates examples of NTN scenarios to which some examples of the present disclosure may be applied.

[0023] Figure 11 illustrates examples of NTN scenarios to which some examples of the present disclosure may be applied.

[0024] FIG. 12 illustrates examples of sensing operations to which some examples of the present disclosure may be applied.

[0025] FIG. 13 illustrates four topologies for ambient IoT in a wireless communication system to which the present disclosure can be applied.

[0026] Figure 14 is a flowchart illustrating a procedure for an ambient IoT device to access a reader device.

[0027] FIG. 15 illustrates cases of topology 1 for ambient IoT to which some examples of the present disclosure may be applied.

[0028] FIG. 16 illustrates cases of topology 2 for ambient IoT to which some examples of the present disclosure may be applied.

[0029] FIG. 17 illustrates the operation of a device for device-to-device communication in a wireless communication system to which the present disclosure can be applied.

[0030] FIG. 18 illustrates the operation of a device for device-to-device communication in a wireless communication system to which the present disclosure can be applied.

[0031] Hereinafter, preferred embodiments of the present disclosure will be described in detail with reference to the accompanying drawings. The detailed description set forth below, together with the accompanying drawings, is intended to explain exemplary embodiments of the present disclosure and is not intended to represent the only embodiments in which the present disclosure may be practiced. The following detailed description includes specific details to provide a thorough understanding of the present disclosure. However, one of ordinary skill in the art will appreciate that the present disclosure may be practiced without these specific details.

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

[0033] In the present disclosure, when a component is said to be "connected," "coupled," or "connected" to another component, this may include not only a direct connection but also an indirect connection in which another component exists between them. Furthermore, the terms "comprises" or "has" in the present disclosure specify the presence of the mentioned features, steps, operations, elements, and / or components, but do not exclude the presence or addition of one or more other features, steps, operations, elements, components, and / or groups thereof.

[0034] In this disclosure, terms such as "first," "second," etc. are used only to distinguish one component from another, are not used to limit the components, and do not limit the order or importance of components unless specifically stated otherwise. Accordingly, within the scope of this disclosure, a first component in one embodiment may be referred to as a second component in another embodiment, and similarly, a second component in one embodiment may be referred to as a first component in another embodiment.

[0035] The terminology used in this disclosure is for the purpose of describing particular embodiments and is not intended to limit the scope of the claims. As used in the description of the embodiments and the appended claims, the singular forms "a," "an," and "the" are intended to include the plural forms as well, unless the context clearly dictates otherwise.

[0036] In this disclosure, "A or B" can mean "only A," "only B," or "both A and B." In other words, "A or B" in this disclosure can be interpreted as "A and / or B." For example, "A, B or C" in this disclosure can mean "only A," "only B," "only C," or "any combination of A, B and C."

[0037] As used herein, a slash ( / ) or a comma 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 identically to “at least one of A and B.”

[0039] Additionally, in the present disclosure, “at least one of A, B and C” can mean “only A,” “only B,” “only C,” or “any combination of A, B and C.” Additionally, “at least one of A, B or C” or “at least one of A, B and / or C” can mean “at least one of A, B and C.”

[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, "control information" in 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 description, 'when, if, in case of' can be replaced with 'based on'.

[0042] Technical features individually described in 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 / IAB (integrated access backhaul) node.

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

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

[0046] In the present disclosure, "setting or defining" may be interpreted as being set to a device through predefined signaling (e.g., SIB (system information block), MAC, RRC) from a base station or network. In the present disclosure, "setting or defining" may be interpreted as being set to a device through separate signaling or being defined in advance without separate signaling.

[0047] In the present disclosure, transmitting or receiving a channel means transmitting or receiving information or a signal through the 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 the present 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) / 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), 5G NR, and the like.

[0049] The technology described in the present disclosure can be implemented with 6G wireless technology and applied to various 6G systems. For example, the 6G system can have key factors such as enhanced mobile broadband (eMBB), ultra-reliable low latency communications (URLLC), massive machine-type communication (mMTC), artificial intelligence (AI) 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] Figure 1 illustrates a flexible network topology to which some examples of the present disclosure may be applied.

[0052] To compensate for incomplete network coverage areas, a network topology that allows for more flexible and resilient split radio access networks (RANs) may be considered. For this purpose, various nodes, such as integrated access backhaul (IAB) nodes, relays, and radio frequency (RF) repeaters, as illustrated in Figure 1, may be applied, or 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 simply performs the function of signal amplification and forwarding, or in the case of a network-controlled repeater, it may not only amplify and forward signals but also adjust its transmission and reception settings based on information provided by the network. For example, NTN nodes could be satellites or aircraft that provide NTN coverage that terrestrial networks struggle to provide. Beyond these examples, various intermediate points can be introduced to improve the network topology.

[0053] Referring to Figure 1, a split RAN can support the division of a base station into a centralized unit (CU) and one or more distributed units (DUs). The CU and DU can correspond to logical units. The CU can 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 DUs, various intermediate points can be introduced to compensate for this.

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

[0055] In some examples of the present disclosure, the description of a terminal may equally apply not only to a user-side endpoint, but also to an intermediate point corresponding to a terminal in a relative relationship with a network-side endpoint. Similarly, in some examples of the present disclosure, the description of a base station may equally apply not only to a network-side endpoint, but also to an intermediate point corresponding to a base station in a relative relationship with a user-side endpoint. In most cases where there is no additional description of the operations of three or more entities, the communicating entities in the present disclosure are briefly described as terminals and / or base stations (or first nodes and / or second nodes), where the terms terminal and / or base stations (or first nodes and / or second nodes) are interpreted to include / 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 simplicity of explanation, the subjects of the operation may be referred to as terminals and / or base stations (or first nodes and / or second nodes). In addition, the terms terminal and / or base station (or first node and / or second node) may also be interpreted / replaced as in the following examples: For example, the terminal (or first node) and the base station (or second node) may respectively correspond to the first endpoint and the second endpoint; may respectively correspond to the endpoint and the intermediate point; may respectively correspond to the intermediate point and the endpoint; or may respectively correspond to the first intermediate point and the second intermediate point.

[0057] In the present disclosure, there may be zero or more intermediate points between the base station and the terminal. If an intermediate point exists, it may correspond to an IAB node / relay / RF repeater / NTN node, or a node supporting other functions. The intermediate point may be a node with a fixed location or a node with an unfixed location.

[0058] Systems applicable to this disclosure

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

[0060] The communication system (100) applied to the present disclosure 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 a 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 Things) device (110f), and an AI (artificial intelligence) device / server (110g). For example, the vehicle may include a vehicle equipped with a wireless communication function, an autonomous vehicle, a vehicle capable of performing vehicle-to-vehicle communication, etc. Here, the 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.), 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 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 act as a network device (120) to another wireless device (110).

[0061] Wireless devices (110a to 110f) can be connected to a network (130) via a network device (120). AI technology can be applied to the wireless devices (110a to 110f), and the wireless devices (110a to 110f) can be connected to an AI server (110g) via a network (130). The network (130) can be configured using a 3G network, a 4G (e.g., LTE) network, a 5G (e.g., NR), or a 6G network. The wireless devices (110a to 110f) can communicate with each other via the network device (120) / network (130), but can 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). Additionally, an IoT device (110f) (e.g., a sensor) can communicate directly with another IoT device (e.g., a sensor) or another wireless device (110a to 110f).

[0062] Wireless communication / connection (150a, 150b, 150c) can be established between wireless devices (110a to 110f) / network devices (120), network devices (120) / network devices (120). Here, the 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 the wireless communication / connection (150a, 150b, 150c), the wireless device and the network device / wireless device, and the network device and the network device can transmit / receive wireless signals to each other. For example, the wireless communication / connection (150a, 150b, 150c) can transmit / receive signals through various physical channels. To this end, based on various descriptions of the present disclosure, at least some of various configuration information setting processes for transmitting / receiving wireless signals, various signal processing processes (e.g., channel encoding / decoding, modulation / demodulation, resource mapping / demapping, etc.), resource allocation processes, etc., may be performed.

[0063] Device applicable to the present disclosure

[0064] FIG. 3 illustrates an example of a 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 via 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 operational flowcharts disclosed in this document. For example, the processor (202) may process information in the memory (204) to generate first information / signal, and then transmit a wireless signal including the first information / signal via the transceiver (206). In addition, the processor (202) may receive a wireless signal including second information / signal via the transceiver (206), and then store information obtained from 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, the memory (204) may store software code including 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 operational flowcharts disclosed herein. Here, the processor (202) and the memory (204) may be part of a communication modem / circuit / chip designed to implement wireless communication technology. The transceiver (206) may be connected to the processor (202) and may transmit and / or receive wireless signals via at least one antenna (208). The transceiver (206) may include a transmitter and / or a receiver. The transceiver (206) may be used interchangeably with an RF (radio frequency) unit. In the present disclosure, a wireless device may also mean a communication modem / circuit / chip.

[0067] Hereinafter, the 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., a functional layer such as physical (PHY), media access control (MAC), radio link control (RLC), packet data convergence protocol (PDCP), radio resource control (RRC), and service data adaptation protocol (SDAP)). At least one processor (202) may generate at least one Protocol Data Unit (PDU) and / or at least one Service Data Unit (SDU) according to the descriptions, functions, procedures, proposals, methods, and / or operation flowcharts disclosed in this document. At least one processor (202) may generate a message, control information, data, or information according to the descriptions, functions, procedures, proposals, methods, and / or operation flowcharts disclosed in this document. At least one processor (202) can generate a signal (e.g., a baseband signal) comprising a PDU, an SDU, a message, control information, data or information according to the functions, procedures, proposals and / or methods disclosed in this document, and provide the signal to at least one transceiver (206). At least one processor (202) can receive a signal (e.g., a baseband signal) from at least one transceiver (206) and obtain the PDU, SDU, message, control information, data or information according to the descriptions, functions, procedures, proposals, methods and / or operational flowcharts disclosed in this document.

[0068] At least one processor (202) may be referred to as a controller, a microcontroller, a microprocessor, or a microcomputer. The 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 the at least one processor (202). The descriptions, functions, procedures, proposals, methods, and / or operation flowcharts 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. The descriptions, functions, procedures, proposals, methods, and / or operation flowcharts disclosed in this document may be included in the at least one processor (202), or may be stored in at least one memory (204) and executed by the at least one processor (202). The descriptions, functions, procedures, suggestions, 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) can be connected to at least one processor (202) and can store various forms of data, signals, messages, information, programs, codes, instructions and / or commands. The at least one memory (204) can be configured as a read only memory (ROM), a random access memory (RAM), an erasable programmable read only memory (EPROM), a flash memory, a hard drive, a register, a cache memory, a computer readable storage medium and / or a combination thereof. The at least one memory (204) can be located internally and / or externally to the at least one processor (202). In addition, the at least one memory (204) can be connected to the at least one processor (202) via various technologies such as a wired or wireless connection.

[0070] At least one transceiver (206) can transmit user data, control information, wireless signals / channels, etc., mentioned in the methods and / or flowcharts of this document to at least one other device. At least one transceiver (206) can receive user data, control information, wireless signals / channels, etc. mentioned in the descriptions, functions, procedures, proposals, methods and / or flowcharts disclosed in this document from at least one other device. For example, at least one transceiver (206) can be connected to at least one processor (202) and can transmit and receive wireless signals. For example, at least one processor (202) can control at least one transceiver (206) to transmit user data, control information, or wireless signals to at least one other device. Furthermore, at least one processor (202) can 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. mentioned in the descriptions, functions, procedures, proposals, methods and / or operational flowcharts disclosed in this document via 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) may convert user data, control information, wireless signals / channels, etc. processed by at least one processor (202) from a baseband signal to an RF band signal. For this purpose, 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 different terms in terms of functionality. For example, the processor (202) may be referred to as a control unit, the transceiver (206) as a communication unit, and the memory (204) as a storage unit. In some cases, the communication unit may be used to mean at least a portion 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 a portion of various devices. For example, the structure of the wireless device illustrated in FIG. 3 can be at least a portion of various devices described with reference to FIG. 2 (e.g., a robot (110a), a vehicle (110b-1, 110b-2), an XR device (110c), a portable device (110d), a home appliance (110e), an IoT device (110f), an AI device / server (110g)). Furthermore, according to various embodiments, in addition to the components illustrated in FIG. 3, the device may further include other components.

[0073] For example, the device may be a portable device such as a smartphone, a smart pad, a wearable device (e.g., a smart watch, smart glasses), or a portable computer (e.g., a 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 image information / signals, audio information / signals, data, and / or information input from a user.

[0074] For example, the device may be a mobile device such as a mobile robot, a vehicle, a train, an aerial vehicle (AV), a ship, etc. In this case, the device may further include at least one of a driving unit including at least one of an engine, a motor, a power train, wheels, brakes, and a steering unit of the device, a power supply unit including a wired / wireless charging circuit, a battery, etc. that supplies power, a sensor unit that senses status 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 obtains location information of the mobile device through a global positioning system (GPS) and various sensors.

[0075] For example, the device may be an XR device such as an HMD, a head-up display (HUD) installed in a vehicle, a television, a smartphone, a computer, a wearable device, a home appliance, a 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 obtains control information, data, etc. from the outside and outputs the generated XR object, and a sensor unit that senses status information, environmental 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. types 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 status information, environmental information, and user information of the device or its surroundings, and a driving unit that performs various physical actions, such as moving the robot joints.

[0077] For example, the device may be an AI device such as a TV, a projector, a smartphone, a PC, a laptop, a digital broadcasting terminal, a tablet PC, a wearable device, a set-top box (STB), a radio, a washing machine, a refrigerator, digital signage, a robot, a 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 status information, environmental information, and user information of the device or its surroundings, and a training unit that trains a model composed of an artificial neural network using learning data.

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

[0079] Communication procedures

[0080] FIG. 4 exemplarily illustrates a 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 operations 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 operations performed prior thereto.

[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 can include a plurality of synchronization signals (e.g., a primary synchronization signal, a secondary synchronization signal) classified according to a structure or purpose. Through this, the terminal (110) can confirm the boundaries of the frame, subframe, slot, and / or symbol of the base station (120) and obtain information (e.g., a cell identifier) ​​about the base station (120).

[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 properties, characteristics, and / or capabilities of the base station (120) required to access the base station (120) and use the service, and can be classified according to the content (e.g., whether it is essential for access), transmission structure (e.g., channel used, whether it is provided in an on-demand manner), etc., and can be classified into, for example, a master information block (MIB) and a system information block (SIB). If necessary, the terminal (110) can transmit a signal requesting system information before receiving the system information. Such requesting and providing of system information may be performed after a random access procedure described below.

[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 (e.g., a random access preamble, a random access response (RAR) message, etc.) for a random access procedure based on information related to a random access channel of the base station (120) obtained through system information (e.g., channel position, channel structure, structure of a supported preamble, etc.). For example, the terminal (110) may transmit a preamble (e.g., message 1 (MSG1)) over a random access channel, receive a random access response (RAR) message (e.g., message 2 (MSG2)), transmit a message (e.g., message 3 (MSG3)) including information related to the terminal (110) (e.g., identification information) using scheduling information included in the RAR message to the base station (120), and receive a message for contention resolution and / or connection establishment (e.g., message 4 (MSG4)). As another example, MSG1 and MSG3 may be transmitted and received as one message (e.g., message A (MSG A)), or MSG2 and MSG4 may be transmitted and received as one 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 can be defined in various layers, such as a layer that controls a 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) can perform at least one of signaling for establishing a connection, signaling for determining settings related to communication, and signaling for indicating 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, transmit, and / or receive data based on signaling of control information. 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 information bits. For example, when receiving data, the terminal (110) or the base station (120) can perform at least one of signal extraction from resources, waveform demodulation for each antenna, signal arrangement considering layer mapping, constellation demapping, descrambling, and channel decoding.

[0087] 6G system core technologies

[0088] As core implementation technologies of the 6G system, technologies such as artificial intelligence (AI), THz (terahertz) communication, optical wireless technology, free space optics (FSO) backhaul network, massive MIMO (multiple input multiple output) 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] Incorporating AI into communications can streamline and improve real-time data transmission. AI can use numerous analytics to determine how complex target tasks should be performed. This means AI can increase efficiency and reduce processing delays. Time-consuming tasks such as handovers, network selection, and resource scheduling can be performed instantly using AI. AI can also play a crucial role in machine-to-machine (M2M), machine-to-human, and human-to-machine communications. Furthermore, AI can facilitate rapid communication in brain-computer interfaces (BCIs). AI-based communication systems can be supported by metamaterials, intelligent structures, intelligent networks, intelligent devices, intelligent cognitive radios, self-sustaining wireless networks, and machine learning.

[0091] The following describes a functional framework for AI / ML operations.

[0092] Below, to explain AI (or AI / ML) more specifically, the terms can be defined as follows.

[0093] - Data collection: Data collected from network nodes, management entities, or terminals 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 the data and obtain a trained AI / ML model for inference.

[0096] - AI / ML Inference: The process of making predictions or inducing decisions based on collected data and the AI ​​model using a trained AI model.

[0097] Life Cycle Management (LCM) procedures for AI / ML models (i.e., model training, model deployment, model inference, model monitoring, model updates, etc.) can be divided into functionality-based LCM and model-based LCM. In functionality-based LCM, AI / ML models may not be identified by the network, and the network can direct the activation / deactivation / fallback / switching of AI / ML functionality. In model-ID (identifier)-based LCM, AI / ML models can be identified by the network, and the network / terminal can activate / deactivate / select / switch AI / ML models based on the model ID.

[0098] FIG. 5 exemplarily illustrates a functional framework for AI / ML operations to which some examples of the present disclosure may be applied.

[0099] Figure 5 illustrates a general functional architecture relevant to both Functionality-based LCM and Model-based LCM. Some of the functions or some of the data / information / command flows (i.e., arrows) illustrated in Figure 5 may be omitted.

[0100] Referring to FIG. 5, a general functional framework can be configured to include a data collection function (10), a model training function (20), a management function (30), an inference function (40), and a model storage function (50).

[0101] The Data Collection function (10) is a function that provides input data to the Model Training function (20), Management function (30), and Inference function (40). The Data Collection function (10) can perform data preparation based on raw data and provide input data processed through data preparation. Examples of raw data may include received data / measurement data from terminals or other network entities, inference / output of AI / ML models, etc. The Data Collection function (10) may be performed by a single entity (e.g., terminal, network node, etc.) or may be performed by multiple entities.

[0102] Here, training data (11) refers to data required as input for the AI / ML Model Training function (20). Monitoring data (12) refers to data required as input for the Management (30) of the AI / ML model or AI / ML function. Inference data (13) refers to data required as input for the AI / ML Inference function (30).

[0103] The Model Training function (20) is a function that performs AI / ML model training, validation, and testing, which can generate model performance metrics that can be used as part of the AI / ML model testing procedure. The Model Training function (20) can perform data preparation (e.g., data pre-processing and cleaning, forming, and transformation) based on the Training Data (11) transferred from the Data Collection function (10), if necessary.

[0104] Trained / Updated Model (21): If there is a Model Storage function (50), it is used to pass a trained, validated and tested AI / ML model to the Model Storage function (50) or to pass an updated version of the model to the Model Storage function (50).

[0105] The Management function (30) is a function that supervises the operation of the AI / ML model or AI / ML function. In addition, the Management function (30) may perform decisions to ensure appropriate inference operations based on data received from the Data Collection function (10) (i.e., Monitoring Data (12)) and / or data received from the Inference function (40) (i.e., Inference Output (41)).

[0106] Management Instruction (32) is information required as input to manage the Inference function (40). The relevant information may include selection / (de)activation / switching of an AI / ML model or AI / ML-based function, and may also include fallback to non-AI / ML operations (i.e., not relying on the inference process).

[0107] A Model Transfer / Delivery Request (33) can be used to request model(s) from Model Storage (50).

[0108] A Performance Feedback / Retraining Request (31) refers to information required as input to the Model Training function (20) (e.g., for the purpose of (re)training or updating the model).

[0109] The Inference function (40) is a function that provides output from the process of applying an AI / ML model or AI / ML function using data (i.e., Inference Data (13)) provided by Data Collection (10) as input. Data preparation (e.g., data preprocessing and cleaning, formatting, and transformation) may also be performed based on the Inference Data (13) delivered by Data Collection (10). If necessary, the Inference function (40) may also perform data preparation (e.g., data preprocessing and cleaning, forming, and transformation) based on the Inference Data (13) provided by Data Collection function (10).

[0110] Inference Output (41) is data used in the Management function (30) to monitor the performance of an AI / ML model or AI / ML function. Inference Output (41) may include the inference output of the AI / ML model generated by the Inference function (30), and the details of the inference output may vary depending on the use case.

[0111] The Model Storage function (50) stores a learned / updated model that can be used to perform the Inference function (40). The Model Storage function (50) illustrated in FIG. 2 can be used as a reference point (if any) when applicable to protocol termination, model transmission / delivery, and related processes. Furthermore, the Model Storage function (50) is merely an example and is not intended to limit the storage location of actual AI / ML models, and may be omitted.

[0112] Model Transfer / Delivery (51) is used to transfer AI / ML models to inference functions.

[0113] The level of cooperation can be defined as follows depending on the capability of AI / ML functions between multiple nodes, and variations due to combination of multiple levels or separation of any one level are also possible.

[0114] Cat 0a) No collaboration framework: AI / ML algorithms are purely implementation-based and do not require any changes to the wireless interface.

[0115] Cat 0b) This level corresponds to a framework with a modified wireless interface tailored to efficient implementation-based AI / ML algorithms, but without collaboration.

[0116] Category 1) involves inter-node support to improve the AI / ML algorithms of each node. For example, this applies when a specific node receives support from another node (for training, adaptation, etc.) and vice versa. At this level, model exchange between network nodes is not required.

[0117] Category 2) Joint AI / ML tasks can be performed across multiple nodes. This level requires the exchange of AI / ML model commands or network nodes.

[0118] FIG. 5 is a diagram illustrating an overall functional framework for an AI / ML model, and not all functions and / or all data / information / command signals illustrated in FIG. 5 may be performed within a specific node, but only some of them may be performed.

[0119] AI / ML models can be divided into one-side models and two-side models depending on whether training and / or inference are performed on a single node or jointly / sequentially on multiple nodes.

[0120] A one-side model can refer to an AI / ML model in which inference is performed entirely by a single node (e.g., a terminal or network). Here, AI / ML model training can also be performed entirely by a single node. AI / ML model training and inference can be performed by the same node, or they can be performed by separate nodes.

[0121] A two-side model can refer to an AI / ML model in which joint inference is performed across multiple nodes (e.g., terminals and networks). Joint inference refers to inference being performed jointly across multiple nodes. For example, the first part of the inference may be performed by a first node, and the remaining part by a second node. Two-side models can be categorized into several types depending on the training method of the AI / ML model, as follows:

[0122] - First type: AI / ML models can be trained on a single node. In this case, joint training can be performed. The trained model can then be distributed to other nodes / objects.

[0123] - Second type: Joint training of AI / ML models can be performed on multiple nodes / entities (e.g., networks and terminals). Joint training can mean that model generation (e.g., CSI generation part) and model reconstruction (CSI compression by sub-use case) are trained in the same loop for forward activation and backward gradient. In this type, joint training can include both simultaneous training (i.e., model generation training and model reconstruction training are performed simultaneously) and sequential training (i.e., model reconstruction training is performed after model generation training).

[0124] - Third type: Separate training of AI / ML models can be performed on multiple nodes (e.g., networks and terminals). Separate training may mean that training begins sequentially on one node and continues on other nodes. In this case, the first node first performs the AI / ML model and shares the training data with the second node. The second node can then use the shared training data to perform the AI / ML model. For example, training for the CSI generation part may be performed by the terminal, while CSI reconstruction may be performed by the network.

[0125] FIG. 6 illustrates an example of a communication procedure based on an AI / ML model between a first node and a second node to which some examples of the present disclosure may be applied.

[0126] Step 1: In the description of the present disclosure described below, signaling (e.g., information / data / channel / signal, etc.) or a set of signaling between a specific node (e.g., a terminal, a network, etc.) and another node may be interpreted as the signaling or set of signaling of Step 1 used to perform an operation based on an AI / ML model, even if not otherwise mentioned. For example, it may correspond to training data for training (i.e., generation and / or reconstruction) the AI / ML model of FIG. 2, or correspond to inference data used for inference of the AI / ML model, or correspond to feedback for the AI / ML model, etc. If signaling between nodes is not required prior to an operation based on an AI / ML model in the present disclosure, Step 1 may be omitted. If a one-side model is used in the present disclosure, the unidirectional / bidirectional signaling (set) in the present disclosure may correspond to the signaling of Step 1. In addition, when a two-side model is used in the present disclosure, the one-way / two-way signaling in the present disclosure may correspond to one-stage signaling, and also, a repetitive signaling operation may correspond to one-stage signaling.

[0127] For example, in AI / ML model-based beam management (BM), if a base station predicts (i.e., infers) beam(s) with good quality based on an AI / ML model, the base station can receive quality / intensity information for multiple beams from a terminal. Furthermore, if a terminal predicts (i.e., infers) beam(s) with good quality based on an AI / ML model, the terminal can receive multiple beams from the base station.

[0128] Step 2: In the description of the present disclosure described below, an operation (e.g., calculation, selection, prediction, etc.) in a specific node (e.g., terminal, network, etc.) or a joint operation (e.g., calculation, selection, prediction, etc.) in multiple nodes (e.g., terminal, network, etc.) may correspond to a step 2 operation based on one or more functions in the functional framework of the AI / ML model, even if not mentioned separately. For example, it may correspond to training (i.e., generation and / or reconstruction) of the AI / ML model in FIG. 2, or it may correspond to inference of the AI / ML model, etc. When a one-side model is used, an operation performed by a single node in the present disclosure may correspond to a step 2 operation, and also, when a two-side model is used, a joint operation performed by multiple nodes in the present disclosure may correspond to a step 2 operation.

[0129] For example, in an AI / ML model-based BM, the base station can use quality / intensity information for multiple beams received from the terminal as inference data to predict (i.e., infer) beam(s) with good quality based on the AI / ML model. Furthermore, the terminal can measure multiple beams received from the base station and use the measurement results as inference data to predict (i.e., infer) beam(s) with good quality based on the AI / ML model.

[0130] Step 3: In the description of the present disclosure described below, the signaling (e.g., information / data / channel / signal, etc.) or set of signaling between a specific node (e.g., terminal, network, etc.) and another node may be interpreted as a three-step signaling or set of signaling generated due to (as a result of) an operation based on an AI / ML model, even if not otherwise mentioned. For example, it may correspond to an output resulting from inference of the AI / ML model in FIG. 2. If signaling between nodes is not required as a result of an operation based on an AI / ML model in the present disclosure, Step 3 may be omitted. If a one-side model is used in the present disclosure, the one-way / two-way signaling (set) in the present disclosure may correspond to the three-step signaling. In addition, if a two-side model is used in the present disclosure, the one-way / two-way signaling in the present disclosure may correspond to the three-step signaling, and furthermore, a repetitive signaling operation may correspond to the three-step signaling.

[0131] For example, in an AI / ML model-based BM, the base station can transmit to the terminal the beam(s) predicted based on the AI / ML model as candidates so that the terminal can determine the optimal beam. Furthermore, the terminal can report to the base station the beam(s) predicted based on the AI / ML model to request the base station to transmit the candidate beams as candidates for determining the optimal beam.

[0132] THz communication (terahertz communication)

[0133] Data transmission rates can be increased by increasing bandwidth. This can be achieved by utilizing sub-THz communications with wide bandwidths and applying advanced massive MIMO technology. THz waves, also known as sub-millimeter waves, typically refer to the frequency range between 0.1 THz and 10 THz, with corresponding wavelengths ranging from 0.03 mm to 3 mm. The 100 GHz to 300 GHz band (the sub-THz band) is considered a key part of the THz spectrum for cellular communications. Adding the sub-THz band to the mmWave band will increase 6G cellular capacity. Among the defined THz bands, 300 GHz to 3 THz lies in the far infrared (IR) frequency band. While part of the optical band, the 300 GHz to 3 THz band lies at the boundary of the optical band, immediately following the RF band. Therefore, this 300 GHz to 3 THz band exhibits similarities to RF.

[0134] FIG. 7 illustrates an electromagnetic spectrum to which some examples of the present disclosure may be applied.

[0135] Key characteristics of THz communications include (i) the widely available bandwidth to support very high data rates, and (ii) the high path loss at high frequencies (which necessitates highly directional antennas). The narrow beamwidths generated by highly directional antennas reduce interference. The small wavelength of THz signals allows for a significantly larger number of antenna elements to be integrated into devices and base stations operating in this band. This enables the use of advanced adaptive array technologies to overcome range limitations.

[0136] Transmitting system information (e.g., MIB) in a cell in the THz frequency band can be inefficient because the beam width in high-frequency bands narrows, requiring more beam sweeps to cover the entire cell area. This method is particularly inefficient when there are only a few users within the cell.

[0137] FIG. 8 exemplarily illustrates a system information transmission / reception procedure to which some examples of the present disclosure may be applied.

[0138] The example of Fig. 8 is applicable not only to THz communication environments but also to 6G communication environments where THz communication is not applicable. Furthermore, the procedure illustrated in Fig. 8 can be combined with various embodiments of the present disclosure described below. For example, the embodiments described below can be performed based on system information acquired through the procedure illustrated in Fig. 8.

[0139] In step S810, the second node (120) (e.g., 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 an SFN (system frame number), a PDCCH configuration for SIB1, cell barring, cell re-selection, and subcarrier spacing generated in a higher layer, and may include at least one of an SFN, a half frame indicator, and an SSB index (synchronization signal / PBCH (physical broadcast channel) block index) generated in a physical layer. For this purpose, as an example, cell #1 and cell #2 may have a relationship of a secondary cell and a primary cell.

[0140] At step S830, the first node (110) (e.g., a terminal) can acquire synchronization for cell #1. Synchronization can be acquired by detecting a synchronization signal. Typically, synchronization is acquired before receiving system information. However, since the system information for cell #1 is received from cell #2, synchronization acquisition for cell #1 can be performed after receiving the system information. For example, the terminal can acquire synchronization based on the system information. Alternatively, synchronization acquisition can be performed before step S1010.

[0141] At step S850, the first node (110) may transmit a signal for accessing cell #1. For example, the signal may include a random access preamble. The structure of this signal and the resources (e.g., channels) for transmitting the signal may be identified through system information. Thereafter, at step S1070, the first node (110) and the second node (120) may perform an access procedure for cell #1 and communicate.

[0142] The procedure described with reference to FIG. 8 may be performed when the first node (110) initially connects to cell #1 of the second node (120). Alternatively, a similar procedure may be performed when the first node (110) performs a handover 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 base station other than cell #2 of the second node (120).

[0143] Communications in the THz band are expected to experience extremely severe path loss, and to overcome this, terminals and base stations may be required to use very sharp beams. The use of sharp beams means that terminals and base stations must perform beam control in addition to beamforming, and the number of beams used increases significantly. Consequently, it takes a very long time to align the transmit and receive beams between the base station and terminals. Furthermore, if the beam alignment between the base station and terminals is misaligned due to movement or movement of the terminals, frequent re-alignment is required, which can lead to link instability.

[0144] FIG. 9 illustrates an exemplary beam management procedure to which some examples of the present disclosure may be applied.

[0145] Although FIG. 9 illustrates an example of a procedure for searching and / or selecting beams for THz communication, this procedure is not limited to a THz environment and can also be applied to a 6G communication environment where THz communication is not applied.

[0146] Here, beam may be interpreted as other terms having equivalent technical meanings that can distinguish beams, such as 'spatial domain filter', 'spatial domain transmit filter', 'spatial domain receive filter', reference signal (RS) resource that distinguishes beams, SSB index, etc.

[0147] In step S910, the second node (120) (e.g., a base station) can set resources for beam management to the first node (110) (e.g., a 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 an 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 different port from a port for transmitting an 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.

[0148] In step S930, the second node (120) (e.g., a base station) transmits measurement signals using a plurality of 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 that require measurement, and may also be transmitted in a multi-beam transmission method that forms a plurality of beams simultaneously to reduce sweeping time. Here, the multi-beam transmission may be performed based on at least one of a multi-panel, a sub-array, and a true time delay (TTD).

[0149] At step S950, a first node (110) (e.g., a terminal) may transmit a feedback signal to a 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 at step S1030.

[0150] In step S970, 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 reception 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 that the transmission operation from the first node (110) can also be performed using a beam that has a reciprocal relationship with the beam selected in step S1050. If channel reciprocity is not established, a procedure including transmission of measurement signal(s) by the first node (110) and transmission of feedback signal(s) by the second node (120) may be performed first to determine the transmission beam of the first node (110).

[0151] non-terrestrial networks (NTN)

[0152] Figures 10 and 11 illustrate examples of NTN scenarios to which some examples of the present disclosure may be applied.

[0153] NTN can represent a network or network segment that uses radio frequency (RF) resources mounted on a satellite (or unmanned aerial system (UAS) platform).

[0154] Figure 10 shows an example of a typical scenario of an NTN based on a transparent payload, and Figure 11 shows an example of a typical scenario of an NTN based on a regenerative payload.

[0155] Referring to Figure 10, a 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. The beam footprint can refer to the area where the signal transmitted by the satellite can be received.

[0156] Referring to Figure 11, a satellite (or UAS platform) can establish a service link with a terminal. A satellite (or UAS platform) connected to a terminal can be connected to another satellite (or UAS platform) via an inter-satellite link (ISL). The other satellite (or UAS platform) can be connected to a gateway via a feeder link. Based on the regenerated payload, the satellite can be connected to a data network through another satellite and the gateway. If an ISL does not exist between the satellite and another satellite, a feeder link between the satellite and the gateway may be required.

[0157] Figures 10 and 11 are only 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 (e.g., with onboard 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) can vary depending on the onboard antenna diagram and the minimum elevation angle.

[0158] For example, a transparent payload may include radio frequency filtering, frequency conversion, and amplification. Therefore, the waveform signal repeated by the payload may remain unchanged.

[0159] For example, a regenerative payload may include radio frequency filtering, frequency conversion and amplification, demodulation / decoding, switching and / or routing, and coding / modulation. For example, a regenerative payload may be substantially equivalent to mounting all or part of a base station function on a satellite (or UAS platform).

[0160] Integrated Sensing and Communication (ISAC)

[0161] Wireless sensing is a technology that uses radio frequencies to determine the instantaneous linear velocity, angle, distance (or range) of an object, and thus obtain information about the characteristics of the environment and / or objects within the environment. Because radio frequency sensing does not require a networked device to connect to the object, it can provide a service for object positioning without a device. The ability to obtain range, velocity, and angle information from radio frequency signals can enable a wide range of new capabilities, such as various object detection, object recognition (e.g., vehicles, humans, animals, UAVs), and high-precision localization, tracking, and activity recognition. Wireless sensing services can provide information to a variety of industries (e.g., drones, smart homes, V2X, factories, railways, public safety, etc.), enabling 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 can utilize non-3GPP type sensors (e.g., radar, cameras) to further support 3GPP-based sensing. For example, the operation of wireless sensing services, such as sensing operations, may depend on the transmission, reflection, and scattering of wireless sensing signals. Therefore, wireless sensing offers an opportunity to enhance existing communication systems from a communications network to a wireless communication and sensing network.

[0162] FIG. 12 illustrates examples of sensing operations to which some examples of the present disclosure may be applied.

[0163] Specifically, Fig. 12(a) shows an example of a monostatic sensing operation using a sensing receiver and a sensing transmitter located in the same location. Fig. 12(b) shows an example of a bistatic sensing operation using a sensing receiver and a sensing transmitter located in separate locations. A sensing signal transmitted from a sensing transmitter is reflected / scattered by a sensing object, and the sensing receiver can receive the signal, and extract / obtain sensing data based on the received signal. A sensing result can be generated / determined through appropriate processing of the sensing data. The sensing result can be provided to a trusted third-party entity / service outside the 3GPP system via an entity / service within the 3GPP system.

[0164] A method for transmitting and receiving signals in a wireless communication system supporting the Ambient Internet of Things (A-IoT).

[0165] 3GPP IoT can be applied to indoor / outdoor environments, base station characteristics (e.g., macro / micro / pico cell-based deployments), connection topology (e.g., nodes that can communicate with target devices such as base stations, terminals, relay terminals, repeaters, etc.), TDD / FDD and licensed / unlicensed spectrum frequency bands, coexistence of terminals and infrastructure in frequency bands of 3GPP technologies, and assumption of device-initiated / terminated traffic.

[0166] In one embodiment of the present disclosure, three types of IoT devices may be utilized.

[0167] - Device A: A device that does not store energy and does not generate independent signals (i.e., backscattering transmission).

[0168] - Device B: A device that stores energy and does not generate an independent signal (i.e., backscattering transmission), and use of the stored energy may include amplification of the reflected signal.

[0169] - Device C: A device that stores energy and generates an independent signal (i.e., includes an active RF component for transmission).

[0170] The present disclosure relates to a signal transmission and reception method of devices A and B that perform communication through backscattering transmission among three types of devices. However, this is only one embodiment, and various embodiments of the present disclosure can also be applied to device C.

[0171] Additionally, at least one of the following four topologies may be applied as an example of the present disclosure.

[0172] FIG. 13 illustrates four topologies for ambient IoT in a wireless communication system to which the present disclosure can be applied.

[0173] - Topology (1): BS <-> Ambient IoT Device

[0174] - Topology (2): BS <-> intermediate node <-> ambient IoT device

[0175] - Topology (3): BS <-> Assisting node <-> Ambient IoT device <-> BS

[0176] - Topology (4): UE <-> Ambient IoT Device

[0177] Here, the BS may be included in or replaced by the gNB, and may be a distribution unit (gNB-DU) of the gNB. Furthermore, the ambient IoT device may be replaced by a UE, a remote UE, a device, or a tag. An intermediate node (IN) may be at least one of a relay node, an integrated access backhaul (IAB) node, a relay UE, or a repeater of the network. In the present disclosure, the gNB and the IN may be collectively referred to as a reader.

[0178] For example, for topology (1), the possibility of BS Rx and BS Tx may be included in different BSs. For topologies (2) and (3), the intermediate nodes and auxiliary nodes may be relay terminals, IAB nodes, repeaters, etc. that enable ambient IoT.

[0179] The present disclosure describes a method for transmitting and receiving signals in topologies 1 and 2, in which direct communication (i.e., mono-static communication) is performed between a base station (or / and intermediate node) and an IoT device among four topologies. However, this is only one embodiment, and the present disclosure may also be applied to topologies 3 and / or 4.

[0180] Hereinafter, in the description of the present disclosure, the direction from base station to device in topology 1 is referred to as DL or R2D (reader-to-device) or R2T (reader-to-tag), and the direction from device to base station is referred to as UL or D2R (device-to-reader) or T2R (tag-to-reader). The base station transmits an R2D (or R2T) message or data / information to the device through R2D (or R2T) signaling, and the device transmits a D2R (or T2R) message or data / information to the base station through D2R (or T2R) signaling.

[0181] In addition, in the following description of the present disclosure, in topology 2, the direction from intermediate node (IN) to device is referred to as DL or R2D (reader-to-device) or R2T (reader-to-tag), and the direction from device to IN is referred to as UL or D2R (device-to-reader) or T2R (tag-to-reader). The IN transmits an R2D (or R2T) message or data / information to the device through R2D (or R2T) signaling, and the device transmits a D2R (or T2R) message or data / information to the IN through D2R (or T2R) signaling.

[0182] In addition, in the description of the present disclosure below, transmission of an R2D signal or R2D data / information may include a physical reader-to-device channel (PRDCH), and transmission of a D2R signal or D2R data / information may include a physical device-to-reader channel (PDRCH).

[0183] In describing the present disclosure, “ / ” means “and”, “or”, or “and / or”, depending on the context.

[0184] The present disclosure proposes a method for transmitting and receiving signals between a tag (e.g., an IoT device or device) and a reader (e.g., a BS, gNB, intermediate node, UE, etc.).

[0185] Figure 14 is a flowchart illustrating a procedure for an ambient IoT device to access a reader device.

[0186] Specifically, the connection procedure may consist of an MSG0 transmission / reception procedure, an MSG1 transmission / reception procedure, an MSG2 transmission / reception procedure, an MSG3 transmission / reception procedure, an MSG4 transmission / reception procedure, and an MSG5 transmission / reception procedure.

[0187] 1) MSG0 transmission and reception procedure

[0188] A leader device can transmit MSG0 (e.g., a query signal and / or PDCCH order) to an ambient IoT device. Here, one or more leader devices can transmit MSG0 according to the instructions of the upper node. For example, multiple INs (i.e., multiple terminals) managed by the same base station can transmit MSG0 according to the instructions of the base station.

[0189] For example, if MSG0 is a query signal, the terminal can determine whether to transmit MSG1 based on MSG0. MSG0 can be used as a DL sync signal, such as PSS / SSS. For example, MSG0 can be reused as a DL sync signal, such as PSS / SSS, or defined as a new sync signal.

[0190] At this time, MSG0 may include connection-related system information. For example, the connection-related system information may include a timer value for connection operations, information related to the time interval during which MSG1 transmission is possible (e.g., information related to the start time, length, window pattern, etc.). Additionally or alternatively, the connection-related system information may be transmitted via a separate MSG 0 for each specific device type, and the MSG 0 may indicate that the system information applies only to the specific device type.

[0191] Additionally or alternatively, MSG0 may include information for resolving conflicts. For example, MSG0 may include probability-based access information, UE ID-based access information, early indication-based access information, UE group / type-based access information, service / access type-based access information, etc.

[0192] 2) MSG1 transmission and reception procedure

[0193] The ambient IoT device can (re)transmit MSG1 to the reader device. For example, the ambient IoT device can (re)transmit MSG1 to the reader device using backscattering. The method described below can also be applied to transmitting and receiving messages subsequent to MSG1 (e.g., MSG 3 / 5).

[0194] As an example of the present disclosure, when MSG1 is transmitted in a slotted ALOHA manner, the ambient IoT device can transmit MSG1 at a time aligned with a specific time point (e.g., a transmission time of a DL sync signal or MSG0 transmitted by a reader device, a CW (carrier wave) transmission time, a backscattering transmission time (e.g., ambient IoT device A or B), etc.). The slotted ALOHA manner is a method of transmitting data by unit time (e.g., slot). As another example, the ambient IoT device can transmit MSG1 by selectively backscattering CW.

[0195] Additionally, MSG 1 may include a sequence for collision avoidance.

[0196] When multiple leader devices transmit MSG0, an ambient IoT device can only respond to one MSG0 transmission. For example, an ambient IoT device can transmit MSG1 in response to the first MSG0 transmission it receives, or it can only respond to the MSG0 transmission it receives with the highest intensity.

[0197] 3) MSG2 transmission and reception procedure

[0198] The ambient IoT device may receive MSG2 (from the reader device) after performing (re)transmission of MSG1. In one example of the present disclosure, MSG2 may include / indicate ACK and / or NACK information. For example, if the reader device successfully receives MSG1 and allows connection, MSG2 may include / indicate ACK. If the reader device does not successfully receive MSG1 or / and does not allow connection, MSG2 may include / indicate NACK.

[0199] For example, if MSG2 includes / indicates ACK, MSG2 may include at least one of information included in MSG1 (e.g., sequence information), transmission / reception resources of MSG1 (e.g., time / frequency resources), time / frequency for transmitting / receiving MSGs (e.g., MSG0, MSG1, MSG2, MSG3, MSG4, and / or MSG5, etc.), or CW time / frequency information for backscattering. If MSG2 includes / indicates NACK, MSG2 may include a back-off time.

[0200] 4) MSG3 transmission and reception procedure

[0201] In one embodiment of the present disclosure, when an ACK including / indicating an ACK is received, the ambient IoT device may transmit MSG3 (to the reader device). For example, the ambient IoT device may transmit MSG3 in a backscattering manner. The selection of a time interval / point in time / frequency / resource for transmitting MSG3 may be determined / selected based on at least one of the transmission / reception time interval / point in time / frequency / resource selection methods of MSG2.

[0202] MSG3 may contain at least one of UE ID, sequence, early indication, UE group / type, connection type, RRC connection / resume request message for initial connection, and C-RNTI MAC CE for UE within RRC_CONNECTED.

[0203] Here, the UE ID (e.g., C-RNTI) may be scrambled, masked, or attached to all UL messages. The sequence may be part or all of the sequence selected for MSG1. In another example, the sequence may be part or all of a newly selected sequence using at least one of the MSG1 sequence selection methods described above. The early indication may include the device type (e.g., device A, device B, or device C) and / or other processing times. The RRC connection / resume request message may include the UE ID (e.g., s-TMSI or resumption ID), etc.

[0204] 5) MSG4 transmission and reception procedure

[0205] An ambient IoT device that transmitted MSG 3 may receive MSG4 (from a reader device). MSG4 may include a UE ID (or / and contention resolution MAC CE) and / or sequence information. Here, the sequence may be selected / determined based on at least one of the MSG1 sequence selection methods described above.

[0206] If MSG4 contains the UE ID (or device ID) or sequence of the ambient IoT device, the ambient IoT device may transmit MSG5 (to the reader device).

[0207] For example, MSG5 may include terminal capability information. For example, the terminal capability information may include capability information related to device type (e.g., device type A, B, C), other processing times, early indication (e.g., device type, other processing times), terminal group / type, connection type, etc. Additionally or alternatively, MSG5 may include at least one of a UE ID, a sequence, and user data.

[0208] The methods proposed in this disclosure can be commonly applied to both topologies 1 and 2, and for convenience of explanation, the gNB and UE1 as IN are referred to as leaders. In addition, the proposed methods of this disclosure can be extended to cases where a leader receiving a backscattering signal (BSS) can directly generate a carrier wave (CW) and transmit it to a device, or where the node transmitting the CW is a separate node / device from the leader.

[0209] Additionally, the Ambient IoT base station (BS) (e.g., a leader) used in the present disclosure may be a base station (e.g., a gNB) in topology 1 and may be a specific UE in topology 2. Additionally, the Ambient IoT device (e.g., a tag) used in the present disclosure may be interpreted as an Ambient IoT device in both topology 1 and / or topology 2.

[0210] Hereinafter, in the description of the present disclosure, a preamble means something that is transmitted at the very front of a specific D2R, R2D transmission, a midamble means something that is transmitted in the middle of a specific D2R, R2D transmission, and a postamble means something that is transmitted at the very back of a specific D2R, R2D transmission. Specifically, the physical channels PRDCH and PDRCH transmit a transport block (TB) (i.e., MAC PDU) of an upper layer, and can also transmit L1 (layer 1) control information or L2 (layer 2) control information (e.g., a MAC header or MAC control element). Here, the PRDCH or PDRCH may start transmission with a preamble and end transmission with a postamble. In other words, the PRDCH or PDRCH may be transmitted after the preamble is transmitted, and the postamble may be transmitted after the transmission of the PRDCH or PDRCH is completed. In addition, a midamble may be included between the transmission of L1 / L2 control information or TB of the PRDCH or PDRCH. In the present disclosure, for the convenience of explanation, the expression "x-amble" may collectively refer to the preamble, midamble, and postamble.

[0211] Meanwhile, the preamble, midamble, and postamble mentioned in this specification may be transmitted together with D2R, R2D transmission (e.g., PDRCH, PRDCH) (i.e., not included in D2R, R2D transmission, but transmitted together before / middle / after D2R, R2D transmission) or may be transmitted while being included in the corresponding D2R, R2D transmission.

[0212] FIG. 15 illustrates cases of topology 1 for ambient IoT to which some examples of the present disclosure may be applied.

[0213] Referring to Fig. 15(a), different leaders, R1 node (leader 1) and R2 node (leader 2), can be responsible for transmitting the R2D channel and receiving the D2R channel, respectively. Here, the R1 node can transmit the carrier wave (CW) signal. In the present disclosure, the case of Fig. 15(a) may be referred to as the D1T1-A1 case.

[0214] Referring to Fig. 15(b), the same leader, the R node, can be responsible for both transmitting the R2D channel and receiving the D2R channel. Here, the CW signal can be transmitted by the R node. In the present disclosure, the case of Fig. 15(b) may be referred to as the D1T1-A2 case.

[0215] Referring to Fig. 15(c), the same leader R node can be responsible for both transmitting the R2D channel and receiving the D2R channel. Here, the CW signal can be transmitted by a separate CW node. In this disclosure, the case of Fig. 15(c) may be referred to as the D1T1-B case.

[0216] The R / R1 / R2 nodes in Fig. 15 may all be base stations or network nodes connected to base stations.

[0217] FIG. 16 illustrates cases of topology 2 for ambient IoT to which some examples of the present disclosure may be applied.

[0218] Referring to Fig. 16(a), different leaders, the R1 node (leader 1) and the R2 node (leader 2), can be responsible for transmitting the R2D channel and receiving the D2R channel, respectively. Here, the CW signal can be transmitted by the R1 node. In the present disclosure, the case of Fig. 16(a) may be referred to as the D2T2-A1 case.

[0219] Referring to Fig. 16(b), the same leader R node can be responsible for both transmitting the R2D channel and receiving the D2R channel. Here, the CW signal can be transmitted by the R node. In this disclosure, the case of Fig. 16(b) may be referred to as the D2T2-A2 case.

[0220] Referring to Fig. 16(c), the same leader R node can be responsible for both transmitting the R2D channel and receiving the D2R channel. Here, the CW signal can be transmitted by a separate CW node. In this disclosure, the case of Fig. 16(c) may be referred to as the D2T2-B case.

[0221] Meanwhile, the R / R1 / R2 nodes in Fig. 16 may all be terminals that serve as intermediate nodes (IN). Alternatively, in D2T2-A1, the R1 node may be a base station and the R2 node may be a terminal, or the R1 node may be a terminal and the R2 node may be a base station.

[0222] Hereinafter, for convenience of explanation in the present disclosure, the R1 node refers to a node that performs R2D signaling / transmission, and the R2 node refers to a node that performs D2R signaling / transmission, but the R1 node and the R2 node are not necessarily limited to different nodes.

[0223] Example 1: Collision avoidance method between multiple leaders in contention-based access

[0224] Devices can receive the same or different R2D signals from different R1 nodes. Furthermore, the D2R signals transmitted by the devices in response can be received by the same or different R2 nodes. Here, the R1 and R2 nodes for a given device can be the same or different. In this manner, the R1 and / or R2 nodes can be base station nodes or terminals.

[0225] For contention-based access of a specific device, different R1 nodes may transmit MSG0 for the device repeatedly, or only one R1 node may transmit MSG0 for the device. In this case, if MSG0 is received from multiple R1 nodes with different time / frequency resources due to duplicate transmission, the device can transmit a response (i.e., MSG1) to MSG0 only to one of the leaders. In other words, if the device receives multiple MSG0s from multiple leaders, it can transmit a response to only one of the MSG0s.

[0226] To this end, different R1 nodes can transmit different x-ambles or L1 / L2 control information to distinguish between them. For example, different R1 nodes A and B can generate sequence_A based on value A and sequence_B based on value B, respectively, and configure x-amble (e.g., preamble) or L1 / L2 control information based on these, and transmit PRDCH channel for MSG0 including x-amble (e.g., preamble) or L1 / L2 control information.

[0227] In addition, even if the device transmits D2R MSG1 to only one leader, multiple R2 nodes may receive the PDRCH for MSG1. For example, R2 nodes A and B (i.e., the R1 node and an R2 node) or C and D (i.e., the R1 node and another R2 node) may receive the same D2R MSG1. Accordingly, one or more R2 nodes may transmit R2D MSG2 in response to MSG1. Here, in order to solve the problem of multiple R2 nodes transmitting MSG2, the R2 node that received MSG1 may transmit some or all of the following information to other R2 nodes, and based on this, the R2 nodes may detect the occurrence of a collision for MSG1.

[0228] - Whether the R2 node in question sent R2D MSG0 to the device in question

[0229] - Device identification information included in the above D2R MSG1 signal (e.g., device random number or device ID (identifier) ​​or device-related information)

[0230] - Time / frequency resource location of the above D2R MSG1 signal

[0231] - All or part of the data or TB or MAC PDU / SDU included in the above D2R MSG1 signal

[0232] - x-amble reception information of the above D2R MSG1 signal

[0233] - Measurement information for the above D2R MSG1 signal

[0234] The R2 node receiving MSG1 can receive the above information from other R2 nodes and, based on the above information, determine that other R2 nodes have also received MSG1 for the same device. In this case, the R2 node can determine that a MSG1 collision has been detected. In this case, when a MSG1 collision occurs, only the R2 node that transmitted R2D MSG0 to the device can transmit MSG2 to the device in response to MSG1 from the device. Here, the R2 node that transmitted MSG0 can transmit MSG2 directly to the device, or can transmit MSG2 to the device through another R1 node connected to the R2 node. If the R2 node that received MSG1 did not receive the above information from other R2 nodes for a certain period of time after receiving MSG1, or if the above information does not include MSG1 reception information for the device, the R2 node that received MSG1 can transmit MSG2 to the device in response to MSG1.

[0235] In addition, if the R2 node that transmitted the R2D MSG0 to the device receives the above information from another R2 node and detects a MSG1 collision based thereon, the R2 node that transmitted the R2D MSG0 can compare the measurement result of the MSG1 reception signal with the measurement information included in the information received from the other R2 node. For example, if the measurement value (e.g., signal strength, quality, etc.) of the MSG1 reception signal received by the other R2 node is greater based on the measurement information included in the information, the R2 node that transmitted the R2D MSG0 can instruct the other R2 node to transmit MSG2 in response to MSG1. In this case, the R2 node that transmitted the R2D MSG0 can stop the contention-based access process for the device without transmitting MSG2. In addition, the R2 node that received the instruction to transmit MSG2 from the R2 node that transmitted the R2D MSG0 can transmit MSG2 to the device to continue / complete the contention-based access process for the device.

[0236] Also, unlike the above-described operation, if multiple R2 nodes receive a PDRCH for MSG1, each R2 node may transmit MSG2 in response to MSG1. Here, the R2 node may transmit MSG2 directly or through another R1 node connected to the R2 node. In this case, the device may receive multiple MSG2s from multiple R2s (or R1 nodes connected to R2s), and thus the device may only respond to one MSG2. That is, MSG3 may be transmitted in response to one MSG2.

[0237] Here, different R2 nodes (or R1 nodes connected to R2) can transmit different x-ambles or L1 / L2 control information. For example, different R2 nodes A and B (or R1 nodes connected to R2) can generate sequence_A based on value A and sequence_B based on value B, respectively, and configure x-amble (e.g., preamble) or L1 / L2 control information based on these, and transmit PRDCH channel for MSG2 including x-amble (e.g., preamble) or L1 / L2 control information. Based on this, the device can transmit MSG3 only for one MSG2 transmission. For example, the device can transmit MSG3 response only for MSG2 that it received first. As another example, the device can receive all PRDCH transmissions only if there is a time interval between different PRDCH transmissions. Accordingly, even if different R2 nodes (or R1 nodes connected to R2) transmit MSG2 with different time / frequency resources, the device may receive only the first MSG2 and may not receive MSG2 transmitted thereafter (if there is no difference of more than a certain time interval).

[0238] Even if a device transmits D2R MSG3 to only one leader (i.e., corresponding to only one MSG2), multiple R2 nodes may receive the PDRCH for MSG3. For example, R2 nodes A and B (i.e., both R1 nodes and R2 nodes) or C and D (i.e., the R1 node and another R2 node) may receive the same D2R MSG3. Accordingly, one or more R2 nodes may transmit R2D MSG4 in response to MSG3. Here, in order to solve the problem of multiple R2 nodes transmitting MSG4, an R2 node that receives MSG3 may forward some or all of the following information to other R2 nodes, and based on this, the R2 nodes may detect the occurrence of a collision for MSG3.

[0239] - Whether the R2 node in question sent R2D MSG0 and / or MSG2 to the device in question.

[0240] - Random number, device ID, or device-related information of the device included in the above D2R MSG1 / 3 signal

[0241] - Time / frequency resource location of the above D2R MSG1 / 3 signal

[0242] - All or part of the data or TB or MAC PDU / SDU included in the above D2R MSG1 / 3 signal

[0243] - x-amble reception information of the above D2R MSG1 / 3 signal

[0244] - Measurement information for the above D2R MSG1 / 3 signal

[0245] The R2 node that received MSG3 can receive the above information from another R2 node and, based on the above information, determine that other R2 nodes have also received MSG3 for the same device. In this case, the R2 node can determine that an MSG3 collision has been detected. In this case, when an MSG3 collision occurs, only the R2 node that sent the R2D MSG2 to the device can send MSG4 to the device in response to the MSG3 of the device. Here, the R2 node that sent the MSG2 can directly send the MSG4 to the device, or it can send the MSG4 to the device through another R1 node connected to the R2 node. If the R2 node that received the MSG3 did not receive the above information from another R2 node for a certain period of time after receiving the MSG3, or if the above information does not include information on receiving the MSG3 for the device, the R2 node that received the MSG3 can send MSG4 to the device in response to the MSG3.

[0246] In addition, if the R2 node that transmitted the R2D MSG3 to the corresponding device receives the above information from another R2 node and detects a MSG3 collision based thereon, the R2 node that transmitted the R2D MSG2 may compare the measurement result for the MSG1 / 3 received signal with the measurement information included in the information from the other R2 node. For example, if the measurement value (e.g., signal strength, quality, etc.) of the MSG1 / 3 received signal received by the other R2 node is greater based on the measurement information included in the information, the R2 node that transmitted the R2D MSG2 may instruct the other R2 node to transmit MSG4 in response to MSG3. In this case, the R2 node that transmitted the R2D MSG2 may stop the contention-based access process for the corresponding device without transmitting MSG4. Additionally, the R2 node that received the instruction to transmit MSG4 from the R2 node that transmitted R2D MSG2 can transmit MSG4 to the device to continue / complete the contention-based access process for the device.

[0247] In the above process, the PDRCH of MSG1 / 3 may include information about the R1 node or R2 node that transmitted MSG0 / 2. For example, the PDRCH of MSG1 / 3 may include x-amble information of the MSG0 / 2 PRDCH or time / frequency resource information of the MSG0 / 2 PRDCH. Alternatively, information about the R1 node or R2 node that transmitted MSG0 / 2 (e.g., leader identification information (ID)) may be included in the MSG0 / 2 PRDCH. A device may transmit information included / related to MSG0 / 2 (e.g., information about the R1 node or R2 node, x-amble information of the MSG0 / 2 PRDCH or time / frequency resource information of the MSG0 / 2 PRDCH, etc.) in the PDRCH of MSG1 / 3. In this case, only the R1 node or R2 node corresponding to the information included in MSG1 / 3 can transmit MSG2 / 4 to the corresponding device.

[0248] In the above process, the device can transmit MSG1 only when the MSG0 measurement result is greater than or equal to a threshold, and / or can transmit MSG3 only when the MSG2 measurement result is greater than or equal to a threshold. In addition, the leader, which is a base station / UE, can transmit MSG2 only when the MSG1 measurement result is greater than or equal to a threshold, and / or can transmit MSG4 only when the MSG3 measurement result is greater than or equal to a threshold.

[0249] Here, the threshold can be set differently for each Ambient IoT service, service area, cell coverage, leader (e.g., IN UE or base station), device, or device group. Based on this, different TX / RX target ranges that are higher than the threshold are set as QoS (quality of service) parameters, and only when the range is confirmed can the leader or device for the corresponding service perform R2D / D2R transmission and reception.

[0250] Example 2: Inventory method between multiple leaders

[0251] In this embodiment, we propose an inventory method between multiple leaders in the D1T1-A1 case (see Fig. 15(a)) or the D2T2-A1 case (see Fig. 16(a)).

[0252] In the present disclosure, an inventory round may mean an action by a leader to identify one or more devices present in its vicinity, and may be performed repeatedly for a certain period of time, for example.

[0253] In the case of D1T1-A1 or D2T2-A1, one or more R1 nodes can transmit one R2D signal such as a query message, and receive D2R response signals from one or more devices that receive the R2D signal. Here, in the case of D1T1-A1 or D2T2-A1, the D2R response signal to the R2D signal can be received by one or more R2 nodes. Through this, the leader(s) can identify that the devices that responded with the D2R response signal are in the vicinity / proximity. Then, the leader(s) can perform an inventory round for the devices that have identified the proximity, and exchange data with the identified devices through this.

[0254] If a specific R1 node performs an inventory round for the device(s) by transmitting the R2D signal, the R1 node may request the surrounding R2 node(s) to transmit a D2R response signal before or immediately after the R2D signal. One or more R2 nodes that receive this request and the D2R response signal may transmit the D2R response signal they received to the R1 node.

[0255] If an R2 node performs an inventory round for a device(s) by transmitting the R2D signal through a neighboring R1 node, the R2 node may request the neighboring R2 node(s) to transmit a D2R response signal before or immediately after the R2D signal. One or more R2 nodes that receive this request and the D2R response signal may transmit the received D2R response signal to the requesting R2 node.

[0256] If the upper node of the R1 / R2 node (e.g., a base station or core network node) performs an inventory round for the device, before or immediately after the R2D signal, the upper node or the R1 node may request the surrounding R2 nodes to transmit a D2R response signal. One or more R2 nodes that receive this request and the D2R response signal may transmit the received D2R response signal to the upper node.

[0257] Here, the D2R response signal transmitted may include some or all of the following information or may be transmitted together with some or all of the following information.

[0258] - Identification information of the device that transmitted the above D2R signal (e.g., device random number, device ID (identifier), or device-related information)

[0259] - Time / frequency resource location of the above D2R signal

[0260] - All or part of the data or TB or MAC PDU / SDU included in the above D2R signal

[0261] - x-amble reception information of the above D2R signal

[0262] - Measurement information for the above D2R signal

[0263] - Inventory round index / identifier or session ID of the R2D signal for the above D2R signal

[0264] If the transmission request of the above D2R response includes a timer, the R2 node may start the timer after receiving the request and transmit the D2R response signal only before the timer expires. If the timer is not included, the R1 / R2 node or the upper node may process only the D2R signals transmitted from the R2 node during a certain period of time after its request as a response to the corresponding R2D signal, and may ignore the remaining transmitted D2R signals. Here, the certain period of time may be defined as the time from one R2D signal, such as the query message, to the next R2D signal transmission. For example, it may be defined as the maximum / minimum time interval between consecutive R2D signal transmissions.

[0265] An R1 / R2 node or an upper node can perform multiple inventory rounds in parallel, simultaneously or overlappingly. Different inventory rounds can be initiated by transmitting different R2D signals, and each R2D signal can indicate a different inventory round index / identifier or session ID. When an R1 / R2 node or an upper node requests neighboring R2 nodes to transmit D2R response signals for one or more inventory rounds, the request can include an index or identifier(s) for a specific inventory round. If an R2 node receives a D2R response signal for a specific inventory round from a device(s), the R2 node can transmit the received D2R response signal(s) for that inventory round together with the index / identifier or session ID for the inventory round.

[0266] Different R2D signal transmissions for different inventory rounds can be distinguished by an x-amble (e.g., preamble) sequence of the PRDCH transmitting the R2D signal, or by L1 / L2 control information or data values ​​of the PRDCH. That is, different R2D signal transmissions for different inventory rounds can be distinguished by an x-amble (e.g., preamble) sequence of the PRDCH, or by L1 / L2 control information or data of the PRDCH including or indicating an index or identifier(s) for a specific inventory round.

[0267] Different D2R response signal transmissions for different inventory rounds can be distinguished by an x-amble (e.g., preamble) sequence of the PDRCH transmitting the D2R signal, or by L1 / L2 control information or data values ​​of the PDRCH. That is, different D2R response signals for different inventory rounds can be distinguished by an x-amble (e.g., preamble) sequence of the PDRCH, or by L1 / L2 control information or data of the PDRCH including or indicating an index or identifier(s) for a specific inventory round.

[0268] When a device transmits a single D2R response signal for a specific inventory round, multiple R2 nodes may receive it and forward it to the R1 / R2 node or the upper node (i.e., the node that initiated the corresponding inventory round). In this case, the R1 / R2 node or the upper node (i.e., the node that initiated the corresponding inventory round) that received it can detect duplicate D2R response signals based on the identification information of the device transmitted together with (included in) the D2R response signal. The R1 / R2 node or the upper node may select one (or multiple) R1 / R2 nodes that received it based on the single or duplicate D2R response signal for the specific device and the measurement information. The R1 / R2 node or the upper node may then transmit configuration information to the selected R1 / R2 node so that the R2D / D2R signal for the corresponding device can be transmitted and received in future processes.

[0269] In the above-described method, both R1 / R2 nodes may be base stations or both may be terminals (i.e., intermediate nodes). Alternatively, the R1 and R2 nodes may be a base station and a terminal, or a terminal and a base station. In the above-described method, the R1 / R2 nodes may be replaced with or include CW nodes.

[0270] Example 3: Time / frequency resource pool method considering frequency shift / hopping

[0271] A base station may set a time / frequency resource pool (or resource set or resource region) for A-IoT communication for one or more base stations or one or more INs acting as a leader. Here, the time / frequency resource pool may be set to at least one of the following:

[0272] - Pool for R2D signal transmission resources

[0273] - Resource pool for D2R signal reception resources

[0274] - Resource pool for R2D signal transmission and D2R signal reception resources

[0275] - Resource pool for CW transmission resources

[0276] - Resource pool for R2D signals and CW transmission resources

[0277] - Resource pool for CW transmission resources and D2R signal reception resources

[0278] - Resource pool for R2D signal transmission and CW transmission resources, and D2R signal reception resources.

[0279] The base station can configure one or more time / frequency resource pools for IN via upper layer messages (e.g., RRC messages or MAC CE) or lower layer messages (e.g., DCI).

[0280] Additionally, the base station can activate or deactivate specific time / frequency resource pool(s) from among one or more time / frequency resource pools configured for a specific IN via upper / lower layer messages (e.g., DCI or MAC CE).

[0281] Additionally, when one resource pool includes both R2D signal transmission and D2R signal reception resources, one R2D frequency channel and N D2R frequency channels may be configured to be included / associated with the same resource pool. Here, N may have an integer value greater than 0, such as 0, 1, 2, or 3.

[0282] For example, if D2R is transmitted with frequency shift and frequency channels 1 to 9 are defined / set, one or more resource pools can be set as follows, and different base stations / cells can be set to perform R2D / D2R transmission and reception using different resource pools.

[0283] Example 1)

[0284] Resource Pool #1 - R2D Transmission: Frequency Channel 3 / D2R Transmission: Frequency Channels 2 and 4

[0285] Resource Pool #2 - R2D Transmission: Frequency Channel 6 / D2R Transmission: Frequency Channels 5 and 7

[0286] Resource Pool #3 - R2D Transmission: Frequency Channel 9 / D2R Transmission: Frequency Channels 8 and 1

[0287] Example 2)

[0288] Resource Pool #4 - R2D Transmission: Frequency Channel 2 / D2R Transmission: Frequency Channels 1 and 3

[0289] Resource Pool #5 - R2D Transmission: Frequency Channel 5 / D2R Transmission: Frequency Channels 4 and 6

[0290] Resource Pool #6 - R2D Transmission: Frequency Channel 8 / D2R Transmission: Frequency Channels 7 and 9

[0291] In addition, when D2R is transmitted with frequency shifting, R2D and D2R are transmitted with frequency hopping, and frequency channels 1 to 9 are defined / set, one or more resource pools are set as follows, and different base stations / cells can be set to perform R2D / D2R transmission and reception using different resource pools.

[0292] Example 1)

[0293] Resource Pool #1 - R2D Transmission: Frequency Channel 3, Frequency Channel 6, Frequency Hopping between Channels 3 and 6 / D2R Transmission: Frequency Channels 2 and 4, Frequency Channels 5 and 7

[0294] Resource Pool #2 - R2D Transmission: Frequency Channel 9, Frequency Channel 6, Frequency Hopping between Channels 9 and 6 / D2R Transmission: Frequency Channels 8 and 1, Frequency Channels 5 and 7

[0295] Example 2)

[0296] Resource Pool #3 - R2D Transmission: Frequency Channel 2, Frequency Channel 5, Frequency Hopping between Channels 2 and 5 / D2R Transmission: Frequency Channels 1 and 3, Frequency Channels 4 and 5

[0297] Resource Pool #4 - R2D Transmission: Frequency Channel 8, Frequency Channel 5, Frequency Hopping between Channels 5 and 8 / D2R Transmission: Frequency Channels 7 and 9, Frequency Channels 4 and 6

[0298] In the above setup, a common frequency channel (e.g., channel 6 in Example 1) from different resource pools can be transmitted by different leaders hopping R2D signals at different times.

[0299] When resource pools are set as above, adjacent base stations or adjacent cells can each set their own resource pools to perform R2D / D2R transmission and reception. For example, adjacent base stations 1, 2, and 3, or adjacent cells 1, 2, and 3 can each set resource pools #1, #2, and #3 (or resource pools #4, 5, and 6) to perform R2D / D2R transmission and reception.

[0300] In the above example, cell 2 or base station 2, where resource pool #2 is set, transmits a PRDCH channel through frequency channel 6, and the device(s) responding to this can transmit a PDRCH channel by performing frequency shift or frequency hopping to channel 5 or 7.

[0301] Here, the NR BWP set in the cell of cell 2 or base station 2 may be set to include the PRDCH frequency channel or resource pool set above. In addition, among multiple frequency channels / resource pools, a PRDCH frequency channel or resource pool may be selected / set so as to include the PRDCH frequency channel or resource pool within the NR BWP set in the cell of cell 2 or base station 2. Here, when the PRDCH uses a DL frequency, the NR BWP may be an NR DL BWP, and may also be an initial DL BWP or an active DL BWP. In addition, when the PRDCH uses a UL frequency, the NR BWP may be an NR UL BWP, and may also be an initial UL BWP or an active UL BWP.

[0302] In addition, the NR BWP set in the cell of cell 2 or base station 2 may be set to include the set PDRCH frequency channel or resource pool. In addition, a PDRCH frequency channel or resource pool may be selected / set so that the NR BWP set in the cell of cell 2 or base station 2 includes the PDRCH frequency channel or resource pool among multiple frequency channels / resource pools. Here, when the PDRCH uses a DL frequency, the NR BWP may be an NR DL BWP, and may also be an initial DL BWP or an active DL BWP. In addition, when the PDRCH uses a UL frequency, the NR BWP may be an NR UL BWP, and may also be an initial UL BWP or an active UL BWP.

[0303] If the frequency resources of some resource pools are not included in the DL / UL active BWP or R2D / D2R frequency area / BWP of the terminal, the terminal can perform R2D / D2R transmission and reception by setting / applying a resource pool excluding the corresponding frequency channel.

[0304] Example) Resource Pool #1

[0305] - R2D transmission: frequency channel 3, frequency channel 6, frequency hopping between channels 3 and 6

[0306] - D2R transmission: frequency channels 2 and 4, frequency channels 5 and 7

[0307] For example, if a terminal with a resource pool set up as in the example above has frequency channels 6 and 7 that are not included in the terminal's UL / DL active BWP or R2D / D2R frequency range / BWP, the terminal can only use channel 3 for R2D transmission and channels 2, 4, and 5 for D2R transmission.

[0308] Example 4: How to categorize resources

[0309] A base station can categorize time / frequency resources for transmitting and receiving R2D / D2R signals (e.g., PRDCH / PDRCH) into the following categories. This categorization of time / frequency resources can be applied to dynamic resources, semi-static resources, or configured resources.

[0310] - TX dedicated resources of base station / IN (i.e. R2D signal transmission resources)

[0311] For example, these resource types may be configured for system information or paging transmission for initial connection of a device.

[0312] - TX and CW resources of the base station / IN (i.e., R2D signal transmission resources and CW transmission resources)

[0313] For example, these resource types may be set up for paging transmissions for the initial connection of a device, or together with RX-only resources for devices that have already completed the connection.

[0314] - TX, CW and RX resources of the base station / IN (i.e. R2D signal transmission resources, CW transmission resources and D2R signal reception resources)

[0315] For example, these resource types could be set up for device-specific message exchange after the devices have completed their initial connection.

[0316] - CW and RX resources of the base station / IN (i.e., CW transmission resources and D2R signal reception resources)

[0317] For example, such a resource type may be configured to cause the device to transmit a delay response to a leader (e.g., a base station or IN).

[0318] - CW transmission-only resources

[0319] For example, these resource types may be configured for CW transmission by a leader (e.g., a base station or IN) or by a separate CW transmitting node (i.e., a non-leader device).

[0320] - Dedicated RX resources for base station / IN

[0321] For example, this resource type could be configured to allow a device to receive CW from a separate CW transmitting node (i.e., a non-leader device) and transmit a delay response to the leader (e.g., a base station or IN).

[0322] When one or more resource pools are configured, the base station or IN can configure / indicate a specific resource pool to be one of the resource categories. For example, when the base station configures a resource pool with a higher layer message (e.g., an RRC message), the base station can configure a specific resource pool to be one of the categories, and can configure / reconfigure / indicate the configured resource pool to be used for the specific category with a higher / lower layer message (e.g., MAC CE or DCI) transmitted to the IN.

[0323] A base station can configure a specific logical channel to be dedicated to D2R, dedicated to R2D, or available for both D2R and R2D.

[0324] If the logical channel is dedicated to D2R, the base station or IN can receive data for the logical channel by selecting a resource from a resource pool of a category that supports D2R transmission resources.

[0325] If the logical channel is dedicated to R2D, the base station or IN can select a resource from a resource pool of a category that supports R2D transmission resources to transmit data for the logical channel.

[0326] If a logical channel is available for both D2R / R2D, the base station or IN can transmit R2D data by selecting a resource from a resource pool in a category that supports R2D transmission resources, and can receive D2R data by selecting a resource from a resource pool in a category that supports D2R transmission resources. In addition, the base station or IN can transmit R2D data or receive D2R data by selecting a resource from a resource pool in a category that supports both D2R / R2D.

[0327] Example 5: Measurement method

[0328] Meanwhile, when leaders are adjacent to each other, R2D signals transmitted by different leaders can be configured to be transmitted on different frequency resources and / or different time resources (e.g., slots), thereby reducing interference between R2D signals. Furthermore, D2R signals received by different leaders can be configured to be transmitted on different frequency resources and / or different time resources (e.g., slots), thereby reducing interference when receiving D2R signals.

[0329] To this end, a reader (e.g., a base station or an IN) may perform a BLER (block error ratio) measurement by receiving a D2R message transmitted by a device and measuring a CRC (cyclic redundancy check) result or may measure the signal strength of the D2R signal (e.g., Reference Signals Received Power (RSRP) or Reference Signal Received Quality (RSRQ) or Received Signal Strength Indicator (RSSI). In addition, the IN may perform a BLER measurement by measuring the number of CRC check failures per unit time for a specific device or a specific device group or for all devices that have successfully connected to the IN or for devices that have failed to connect to the IN, depending on the configuration of the base station.

[0330] The IN can report to the base station about the measured BLER (CRC check result) or signal strength measurements (e.g., RSRP / RSRQ) based on the D2R signals from the devices.

[0331] Here, transmission of IN reports may be performed periodically or may be event-triggered by one of the following:

[0332] - Event 1: BLER is lower than the threshold set by the base station.

[0333] - Event 2: BLER is higher than the threshold set by the base station.

[0334] - Event 3: BLER is lower than the value in the previous report.

[0335] - Event 4: BLER is 1 higher than the value in the previous report.

[0336] - Event 5: RSRP / RSRQ is lower than the threshold set by the base station.

[0337] - Event 6: RSRP / RSRQ is higher than the threshold set by the base station.

[0338] - Event 7: RSRP / RSRQ is lower than the value in the previous report.

[0339] - Event 8: RSRP / RSRQ is higher than the value in the previous report.

[0340] The device may also accumulate the number of ACK / NACKs for D2R signals and report them to a leader (e.g., a base station or IN).

[0341] Based on these IN reports, the base station can configure / instruct the IN to increase its transmit power for CW and / or R2D signals for a specific device or a specific group of devices or all devices connected (belonging to) that IN.

[0342] Additionally, the base station may configure / instruct the IN or UE to measure interference (e.g., RSSI) on a specific channel or specific frequency resources within a channel through which R2D signals and / or D2R signals are transmitted. The IN or UE may measure interference (e.g., RSSI) for a specific cell, a specific BWP, a specific channel, or a specific frequency resource within a channel, depending on the configuration of the base station. The IN or UE may report the interference measurement results to the base station for a specific cell, a specific BWP, a specific channel, or a specific frequency resource within a channel.

[0343] Based on the above reports, the base station can control the power of the IN, the UE, the base station (i.e., its own or another base station), or the device. For example, the base station can transmit a command to control the transmission power of the CW and / or R2D signal for a specific cell of the IN, a specific BWP, a specific channel, or a specific frequency resource within a channel.

[0344] Here, based on the above-described report, the base station can set / instruct to increase the transmit power for the CW and / or R2D signals of the IN for a specific device or a specific group of devices or for all devices connected (belonging to) that IN.

[0345] Additionally, based on the measured power of the measured backscatter signal (reported by the IN or measured by the BS) or sensing by the BS, the BS can change the R2D / D2R channel for the BS or IN.

[0346] Example 6: Method for sharing resource information between base stations

[0347] Step 1) Base station 1 can share information related to time / frequency resources with base station 2. Here, the information related to time / frequency resources can include information on at least one of time / frequency resource(s) used by base station 1, time / frequency resource(s) currently in use, and / or time / frequency resource(s) scheduled to be used.

[0348] Here, information related to the time / frequency resources shared by base station 1 with base station 2 may include at least one of the following information:

[0349] - Time / frequency resource(s) used by base station 1, time / frequency resource(s) currently in use, and / or time / frequency resource(s) to be used.

[0350] - Time / frequency resource(s) used, time / frequency resource(s) currently in use, and / or time / frequency resource(s) scheduled to be used by one or more INs belonging to (connected to) the cell of base station 1.

[0351] - Time / frequency resource(s) indicated / included in the information related to time / frequency resources received by base station 1 from base station 3 (i.e., a base station other than the base station with which time / frequency resource information is shared), time / frequency resource(s) in use and / or time / frequency resource(s) to be used.

[0352] Step 2) Base station 2, which has received information related to time / frequency resources shared by base station 1 in the above-described step 1, can reselect time / frequency resources to be used by base station 2 or INs of base station 2 (i.e., INs connected to base station 2) based on the information.

[0353] Here, the time / frequency resources to be used by base station 2 or INs of base station 2 (i.e., INs connected to base station 2) can be selected or reselected from among the remaining time / frequency resources, excluding the used time / frequency resources, the time / frequency resources being used, and / or the time / frequency resources to be used, which are included in the information related to the time / frequency resources shared by base station 1 in step 1.

[0354] In addition, if the used time / frequency resource(s), the currently used time / frequency resource(s) and / or the scheduled time / frequency resource(s) included in the information related to the time / frequency resources shared by base station 1 in step 1 overlap with the time / frequency resources to be used by base station 2 or INs of base station 2 (i.e., INs connected to base station 2), the time / frequency resources to be used by base station 2 or INs of base station 2 (i.e., INs connected to base station 2) can be reselected by excluding the overlapping time / frequency resources.

[0355] Additionally, similar to step 1 above, base station 2 may share information related to time / frequency resources with base station 1. Here, the information related to time / frequency resources may include information on at least one of time / frequency resource(s) that base station 2 has used, is using, and / or will use. Here, the information related to time / frequency resources shared by base station 2 may modify or confirm the information shared by base station 1, and may include at least one of the following information:

[0356] - Time / frequency resource(s) used by base station 2, time / frequency resource(s) currently in use, and / or time / frequency resource(s) to be used.

[0357] - Time / frequency resource(s) used, time / frequency resource(s) currently in use, and / or time / frequency resource(s) scheduled to be used by one or more INs belonging to (connected to) the cell of base station 2.

[0358] - Time / frequency resource(s) indicated / included in the information related to time / frequency resources received by base station 2 from base station 4 (i.e., a base station other than the base station with which time / frequency resource information is shared), time / frequency resource(s) in use and / or time / frequency resource(s) to be used.

[0359] - Time / frequency resource(s) that base station 2 has used, is using, or is scheduled to use among the time / frequency resource(s) of base station 1 / IN / base station 3 that base station 1 shared in step 1 described above.

[0360] - Request for consent or modification or rejection of the use of the time / frequency resource(s) of Base Station 1 / IN / Base Station 3 shared by Base Station 1 in Step 1 described above.

[0361] Step 3) Base station 1, which has received information related to time / frequency resources shared by base station 2 in the above-described step 2, may perform at least one of the following actions based on the information.

[0362] - Maintain the time / frequency resource(s) that Base Station 1 / IN has used, is using, and / or is scheduled to use, with the consent of Base Station 2.

[0363] - Based on a modification request or rejection from Base Station 2, specific time / frequency resources(s) of Base Station 1 / IN may not be used and time / frequency resources that are being used and / or scheduled to be used may be reselected to avoid them.

[0364] Here, base station 1 can perform step 1 described above again to share information related to the reselected time / frequency resource with base station 2.

[0365] Example 7: Time / frequency resource allocation to INs belonging to a cell of a base station

[0366] When one or more INs perform R2D transmission temporarily or one-shot, such as a wake-up signal, the base station can allocate time / frequency resources for R2D transmission to one or more INs. For example, the base station can transmit a specific DCI or MAC CE to one or more INs and allocate time / frequency resources for R2D transmission through the specific DCI or MAC CE.

[0367] Here, the DCI scheduling the PDSCH transmitting the specific DCI or the MAC CE may scramble the CRC with an identifier of one or more INs (e.g., a terminal-only RNTI (e.g., a C-RNTI or a new IN(intermediate node)-RNTI)), or may scramble the CRC with an identifier for an IN group assigned to a plurality of IN groups (e.g., an IN group RNTI (e.g., a G(group)-RNTI or a new ING(intermediate node group)-RNTI).

[0368] For example, the specific DCI may indicate a time difference / offset and specific time / frequency resources of a specific channel. For example, the time difference / offset may mean an interval between the time difference / offset and the time / frequency resources indicated by the specific DCI. An IN that receives the specific DCI may perform R2D transmission to the device(s) using the time / frequency resources of the indicated channel after the time difference / offset indicated by the DCI.

[0369] As another example, the MAC CE may indicate a time / frequency resource pattern of a specific channel for a certain time period. For example, the time period may be indicated in absolute time units, or may be indicated in time resource units (e.g., slots, symbols, etc.) for the IN's R2D transmission. The IN, upon receiving the MAC CE, may perform R2D transmission for a certain time period according to the time / frequency resource pattern of the indicated channel after the application time of the MAC CE (e.g., the time point at which the IN applies the received MAC CE, which may be set / defined as an offset from the time point at which the MAC CE is received).

[0370] Additionally, if one or more INs perform periodic or pattern-based continuous R2D transmissions (e.g., system information or paging signals), the base station may allocate periodic or continuous time / frequency resources for R2D transmissions to one or more INs. For example, the base station may transmit specific MAC CE and / or RRC messages to one or more INs, and allocate periodic or continuous time / frequency resources for R2D transmissions through the specific MAC CE and / or RRC messages.

[0371] An IN that receives an RRC message or MAC CE that sets up periodic or continuous time / frequency resources can allocate / activate the periodic or continuous time / frequency resources after an application time (e.g., it can mean the time point at which the IN applies the RRC message or MAC CE received, and can be set / defined as an offset from the time point at which the RRC message or MAC CE is received) according to the instructions of the RRC message or MAC CE, and can perform R2D transmission to the device(s) using the periodic or continuous time / frequency resources accordingly.

[0372] A base station can instruct an IN to periodically or continuously transmit a specific R2D transmission to a device(s) using the periodic or continuous time / frequency resources by transmitting control signaling (e.g., an RRC message or MAC CE or DCI) to the IN. Here, the specific R2D transmission can be generated by the base station (or core network) or the IN. For example, when the base station or core network generates the specific R2D message (i.e., the payload for the specific R2D transmission), the base station can transmit the generated specific R2D message (i.e., the payload for the specific R2D transmission) to the IN by including the control signaling (e.g., the RRC message or MAC CE or DCI). In this case, the IN can periodically or continuously transmit an R2D transmission including the received specific R2D message (i.e., the payload for the specific R2D transmission).

[0373] Additionally, the base station may transmit control signaling (e.g., an RRC message or MAC CE or DCI) to the IN to instruct it to stop (or temporarily suspend) the periodic or continuous transmission of the specific R2D transmission. Here, the specific R2D transmission may be a system information, paging, or select message or a query message.

[0374] The base station can deactivate or release the periodic or continuous time / frequency resources by transmitting control signaling (e.g., RRC message or MAC CE) to the IN.

[0375] Additionally, the base station can activate, deactivate, or release the configured / allocated periodic or continuous time / frequency resources by transmitting control signaling (e.g., DCI or MAC CE) to the IN.

[0376] Additionally, if the R2D signal is system information, periodic or continuous time / frequency resources may be configured / defined as resources for transmitting the system information. In this case, the IN may transmit the system information to the device(s) using the configured / defined time / frequency resources.

[0377] If the R2D transmission is paging, periodic or continuous time / frequency resources may be the same as the paging occasion or included in the PO. The IN may use the time / frequency resources to transmit the paging to the device(s).

[0378] A base station can allocate the same or different time / frequency resources to different INs as paging occasions. Here, the base station can designate a specific paging occasion as the time / frequency resources for paging transmissions for a specific paging group. In this case, the IN can transmit paging messages only for a specific paging group to the device(s) during a specific paging occasion.

[0379] FIG. 17 illustrates the operation of a device for device-to-device communication in a wireless communication system to which the present disclosure can be applied.

[0380] FIG. 17 illustrates the operation of a device (i.e., a leader or an intermediate node) based on the proposed methods in the embodiments described above. The example in FIG. 17 is provided for convenience of explanation and does not limit the scope of the present disclosure. Some of the step(s) illustrated in FIG. 17 may be omitted depending on circumstances and / or settings. In addition, the device in FIG. 17 is only an example and may be implemented as the device illustrated in FIG. 3. For example, the processor (202) in FIG. 3 may control the transceiver (206) to transmit and receive channels / signals / data / information, etc., and may also control the processor (202) in FIG. 3 to store the channels / signals / data / information to be transmitted or received in the memory (204).

[0381] Additionally, the operation of FIG. 17 may be processed by one or more processors (202) of FIG. 3. Additionally, the operation of FIG. 17 may be stored in a memory (e.g., one or more memories (204) of FIG. 3) in the form of a command / program (e.g., an instruction, an executable code) for driving at least one processor (e.g., 202) of FIG. 3.

[0382] In FIG. 17, the second device may be a device that transmits a backscattered signal to the first device based on a carrier wave for energy harvesting or backscattering from the first device or from a CW node, and the first device may be a device that receives the backscattered signal from the second device.

[0383] Referring to FIG. 17, the first device transmits a first transmission (e.g., an R2D transmission including a PRDCH) to the second device (S1701).

[0384] Here, a plurality of different transmissions (e.g., R2D transmissions including PRDCH) including the first transmission can be transmitted from a plurality of devices including the first device to the second device.

[0385] The above multiple transmissions may be distinguished based on a sequence of at least one of a preamble, a midamble, and a postamble, or based on control information included in the multiple transmissions. For example, the control information included in the multiple transmissions may be L1 / L2 control information, and may include identification information for the device transmitting the multiple transmissions.

[0386] For example, the plurality of transmissions including the first transmission may be a message for triggering a random access procedure or message 2 (MSG2) in the random access procedure.

[0387] The first device receives a second transmission (e.g., a D2R transmission including a PDRCH) containing information related to the first device among a plurality of devices in response to the first transmission from the second device (S1702).

[0388] Here, the information related to the first device may include at least one of i) information related to at least one of a preamble, a midamble, and a postamble of the first transmission by the first device (e.g., information related to a sequence for at least one of the preamble, the midamble, and the postamble, e.g., a specific value for sequence generation, etc.), ii) time and / or frequency resource information of the first transmission by the first device, and iii) identification information of the first device.

[0389] After receiving the second transmission, the first device may transmit information related to a collision occurrence for the second transmission to at least one of the plurality of devices. For example, the information related to the collision occurrence may include at least one of: i) information indicating that the first device transmitted the first transmission, ii) identification information of the second device included in the second transmission, iii) time and / or frequency resource information of the second transmission, iv) at least a portion of data included in the second transmission, v) reception information for at least one of a preamble, a midamble, and a postamble in the second transmission (e.g., whether at least one of the preamble, the midamble, and the postamble has been received, or information related to a sequence of at least one of the preamble, the midamble, and the postamble, etc.), vi) measurement information for the second transmission (e.g., signal strength, quality, etc.).

[0390] Additionally, the second transmission may be transmitted only if the measurement result for the first transmission is greater than or equal to a threshold. Here, the threshold may be set differently for at least one of the service area, cell coverage, device, and device group. In other words, the threshold may be individually set for at least one of the service area, cell coverage, device, and device group.

[0391] For example, the second transmission may be message 1 (MSG1) transmitted in response to a message for triggering the random access procedure in the random access procedure, or message 3 (MSG3) transmitted in response to message 2 in the random access procedure.

[0392] Additionally, although not specifically described in FIG. 17, the first device (i.e., the reader) may perform an inventory round operation according to the proposed method of Embodiment 2 described above, measurements for the first transmission and / or the second transmission may be performed according to the proposed method of Embodiment 5, and resources for the first transmission and / or the second transmission may be determined according to the proposed method of at least one of Embodiments 3, 4, 6, and / or 7.

[0393] FIG. 18 illustrates the operation of a device for device-to-device communication in a wireless communication system to which the present disclosure can be applied.

[0394] FIG. 18 illustrates the operation of a device (i.e., an Ambient-IoT device or tag) based on the proposed methods in the embodiments described above. The example in FIG. 18 is provided for convenience of explanation and does not limit the scope of the present disclosure. Some of the step(s) illustrated in FIG. 18 may be omitted depending on the situation and / or setting. In addition, the device in FIG. 18 is only an example and may be implemented as the device illustrated in FIG. 3. For example, the processor (202) in FIG. 3 may control the transceiver (206) to transmit and receive channels / signals / data / information, etc., and may also control the processor (202) in FIG. 3 to store the channels / signals / data / information, etc. to be transmitted or received in the memory (204).

[0395] Additionally, the operation of FIG. 18 may be processed by one or more processors (202) of FIG. 3. Additionally, the operation of FIG. 18 may be stored in a memory (e.g., one or more memories (204) of FIG. 3) in the form of a command / program (e.g., an instruction, an executable code) for driving at least one processor (e.g., 202) of FIG. 3.

[0396] In FIG. 18, the second device may be a device that transmits a backscattered signal to the first device based on a carrier wave for energy harvesting or backscattering from the first device or from a CW node, and the first device may be a device that receives the backscattered signal from the second device.

[0397] Referring to FIG. 18, a second device receives a plurality of different transmissions (e.g., an R2D transmission including a PRDCH) from a plurality of devices including the first device, including a first transmission by the first device (e.g., an R2D transmission including a PRDCH) (S1801).

[0398] The above multiple transmissions may be distinguished based on a sequence of at least one of a preamble, a midamble, and a postamble, or based on control information included in the multiple transmissions. For example, the control information included in the multiple transmissions may be L1 / L2 control information, and may include identification information for the device transmitting the multiple transmissions.

[0399] For example, the plurality of transmissions including the first transmission may be a message for triggering a random access procedure or message 2 (MSG2) in the random access procedure.

[0400] The second device transmits a second transmission (e.g., a D2R transmission including a PDRCH) to the first device in response to the first transmission, the second transmission including information related to the first device (S1802).

[0401] Here, the information related to the first device may include at least one of i) information related to at least one of a preamble, a midamble, and a postamble of the first transmission by the first device (e.g., information related to a sequence for at least one of the preamble, the midamble, and the postamble, e.g., a specific value for sequence generation, etc.), ii) time and / or frequency resource information of the first transmission by the first device, and iii) identification information of the first device.

[0402] After receiving the second transmission, the first device may transmit information related to a collision occurrence for the second transmission to at least one of the plurality of devices. For example, the information related to the collision occurrence may include at least one of: i) information indicating that the first device transmitted the first transmission, ii) identification information of the second device included in the second transmission, iii) time and / or frequency resource information of the second transmission, iv) at least a portion of data included in the second transmission, v) reception information for at least one of a preamble, a midamble, and a postamble in the second transmission (e.g., whether at least one of the preamble, the midamble, and the postamble has been received, or information related to a sequence of at least one of the preamble, the midamble, and the postamble, etc.), vi) measurement information for the second transmission (e.g., signal strength, quality, etc.).

[0403] Additionally, the second transmission may be transmitted only if the measurement result for the first transmission is greater than or equal to a threshold. Here, the threshold may be set differently for at least one of the service area, cell coverage, device, and device group. In other words, the threshold may be individually set for at least one of the service area, cell coverage, device, and device group.

[0404] For example, the second transmission may be message 1 (MSG1) transmitted in response to a message for triggering the random access procedure in the random access procedure, or message 3 (MSG3) transmitted in response to message 2 in the random access procedure.

[0405] Additionally, although not specifically described in FIG. 17, the first device (i.e., the reader) may perform an inventory round operation according to the proposed method of Embodiment 2 described above, measurements for the first transmission and / or the second transmission may be performed according to the proposed method of Embodiment 5, and resources for the first transmission and / or the second transmission may be determined according to the proposed method of at least one of Embodiments 3, 4, 6, and / or 7.

[0406] The embodiments described above are combinations of components and features of the present disclosure in a predetermined form. Each component or feature should be considered optional unless explicitly stated otherwise. Each component or feature may be implemented without being combined with other components or features. Furthermore, it is also possible to form 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 self-evident that claims that do not have an explicit citation relationship in the patent claims may be combined to form embodiments or incorporated as new claims through post-application amendments.

[0407] It will be apparent to those skilled in the art that the present disclosure may be embodied in other specific forms without departing from the essential characteristics of the present disclosure. Therefore, the above detailed description should not be construed as limiting in any respect, but rather as illustrative. The scope of the present disclosure should be determined by a reasonable interpretation of the appended claims, and all modifications within the scope of equivalents of the present disclosure are intended to be included within the scope of the present disclosure.

[0408] The scope of the present disclosure includes software or machine-executable instructions (e.g., an operating system, an application, firmware, a program, etc.) that cause operations according to the methods of various embodiments to be executed on a device or a computer, and a non-transitory computer-readable medium having such software or instructions stored thereon and executable on the device or computer. Instructions that can be used to program a processing system to perform the features described in the present disclosure can be stored on / in a storage medium or a computer-readable storage medium, and a computer program product including such a storage medium can be used to implement the features described in the present disclosure. The storage medium can 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 can 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 optionally includes one or more storage devices remotely located from the processor(s). The memory or, alternatively, the non-volatile memory device(s) within the memory comprise a non-transitory computer-readable storage medium. The features described in this disclosure may be incorporated into software and / or firmware stored on any of the machine-readable media, which may control the hardware of the processing system and allow the processing system to interact with other mechanisms that utilize results according to embodiments of the present disclosure. Such software or firmware may include, but is not limited to, application code, device drivers, operating systems, and execution environments / containers.

[0409] Here, the wireless communication technology implemented in the device of the present disclosure may include not only LTE, NR, and 6G, but also Narrowband Internet of Things for low-power communication. For example, NB-IoT technology may be an example of LPWAN (Low Power Wide Area Network) technology and may be implemented with standards such as LTE Cat NB1 and / or LTE Cat NB2, and is not limited to the above-described names. Additionally or alternatively, the wireless communication technology implemented in the device of the present disclosure may perform communication based on LTE-M technology. For example, LTE-M technology may be an example of LPWAN technology and may be called by various names such as eMTC (enhanced Machine Type Communication). For example, LTE-M technology can be implemented by at least one of various standards such as 1) LTE CAT 0, 2) LTE Cat M1, 3) LTE Cat M2, 4) LTE non-BL (non-Bandwidth Limited), 5) LTE-MTC, 6) LTE Machine Type Communication, and / or 7) LTE M, and is not limited to the above-described names. Additionally or alternatively, the wireless communication technology implemented in the device (100, 200) of the present disclosure can include at least one of ZigBee, Bluetooth, and Low Power Wide Area Network (LPWAN) considering low-power communication, and is not limited to the above-described names. For example, ZigBee technology can create personal area networks (PAN) related to small / low-power digital communication based on various standards such as IEEE 802.15.4, and can be called by various names.

[0410] The method proposed in this disclosure is explained with a focus on examples applied to 3GPP LTE / LTE-A, 5G, and 6G systems, but can be applied to various wireless communication systems in addition to 3GPP LTE / LTE-A, 5G, and 6G systems.

Claims

1. A step of transmitting a first transmission to a second device by a first device; and comprising, by the first device, a step of receiving a second transmission from the second device in response to the first transmission; A plurality of different transmissions including the first transmission are transmitted from a plurality of devices including the first device to the second device, A method wherein the second transmission includes information related to the first device among the plurality of devices.

2. In paragraph 1, A method wherein the plurality of transmissions are distinguished based on a sequence for at least one of a preamble, a midamble, and a postamble, or based on control information included in the plurality of transmissions.

3. In paragraph 1, A method according to claim 1, wherein the information related to the first device comprises at least one of i) information related to at least one of a preamble, a midamble, and a postamble of the first transmission by the first device, ii) time and / or frequency resource information of the first transmission by the first device, and iii) identification information of the first device.

4. In paragraph 1, A method further comprising the step of transmitting, by the first device, information related to the occurrence of a collision for the second transmission to at least one of the plurality of devices.

5. In paragraph 4, A method according to claim 1, wherein the information related to the occurrence of the collision comprises: i) information indicating that the first device transmitted the first transmission, ii) identification information of the second device included in the second transmission, iii) time and / or frequency resource information of the second transmission, iv) at least a portion of data included in the second transmission, v) reception information for at least one of a preamble, a midamble, and a postamble in the second transmission, and vi) at least one of measurement information for the second transmission.

6. In paragraph 1, A method in which the second transmission is transmitted only when the measurement result for the first transmission is greater than or equal to a threshold.

7. In paragraph 6, A method wherein the above threshold is set differently for at least one of a service area, cell coverage, device, and group of devices.

8. In paragraph 1, A method wherein the plurality of transmissions including the first transmission are messages for triggering a random access procedure or message 2 (MSG2) in the random access procedure.

9. In paragraph 8, A method wherein the second transmission is message 1 (MSG1) transmitted in response to a message for triggering the random access procedure in the random access procedure or message 3 (MSG3) transmitted in response to message 2 in the random access procedure.

10. The first device is: One or more transceivers for transmitting and receiving wireless signals; and comprising one or more processors controlling one or more of the above transceivers, One or more of the above processors: Transmitting the first transmission to the second device; and is configured to receive a second transmission in response to the first transmission from the second device; A plurality of different transmissions including the first transmission are transmitted from a plurality of devices including the first device to the second device, The first device, wherein the second transmission includes information related to the first device among the plurality of devices.

11. One or more non-transitory computer-readable media storing one or more instructions, The one or more instructions are executed by one or more processors, so that the first device: Transmitting the first transmission to the second device; and Control to receive a second transmission in response to the first transmission from the second device, A plurality of different transmissions including the first transmission are transmitted from a plurality of devices including the first device to the second device, A computer-readable medium wherein the second transmission includes information related to the first device among the plurality of devices.

12. In a processing device set to control a first device, the processing device: one or more processors; and One or more computer memories operatively connected to said one or more processors and storing instructions for performing operations based on execution by said one or more processors, The above actions are: A step of transmitting a first transmission to a second device by a first device; and comprising, by the first device, a step of receiving a second transmission from the second device in response to the first transmission; A plurality of different transmissions including the first transmission are transmitted from a plurality of devices including the first device to the second device, A processing device wherein the second transmission includes information related to the first device among the plurality of devices.

13. A step of receiving, by a second device, a plurality of different transmissions including a first transmission by the first device from a plurality of devices including the first device; and A step of transmitting a second transmission to the first device in response to the first transmission by the second device, A method wherein the second transmission includes information related to the first device among the plurality of devices.

14. The second device is: One or more transceivers for transmitting and receiving wireless signals; and comprising one or more processors controlling one or more of the above transceivers, One or more of the above processors: Receiving a plurality of different transmissions from a plurality of devices including a first device, including a first transmission by the first device; and is configured to transmit a second transmission to the first device in response to the first transmission; A second device, wherein the second transmission includes information related to the first device among the plurality of devices.

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