Method and device for performing uplink transmission / reception in wireless communication system

Abstract

A method and a device for performing uplink transmission / reception in a wireless communication system are disclosed. The method according to one embodiment of the present disclosure may comprise steps in which a terminal: transmits, to a base station, a first random access channel (RACH) for a request of an on-demand system information block (SIB) of a first cell; receives, from the base station, a first response message including redirection information about one or more cells or one or more frequency bands; and, on the basis of the redirection information, transmits, to the base station, a second RACH for an on-demand SIB request of a second cell related to a first frequency band from among the one or more frequency bands or a third cell from among the one or more cells.

Description

Method and device for performing uplink transmission and reception in a wireless communication system

[0001] The present disclosure relates to a wireless communication system, and more particularly, to a method and device for performing uplink transmission and reception 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 performing uplink transmission and reception in a wireless communication system.

[0005] In addition, an additional technical problem of the present disclosure is to provide a method and device for performing a redirection procedure related to an on-demand SIB1 (system information block 1).

[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 one embodiment of the present disclosure may include: transmitting, by a terminal, to a base station a first random access channel (RACH) for requesting an on-demand system information block (SIB) of a first cell; receiving, by the terminal, from the base station a first response message including redirection information for at least one cell or at least one frequency band; and transmitting, by the terminal, to the base station a second RACH for requesting an on-demand SIB of a second cell associated with a first frequency band of the at least one frequency band or a third cell of the at least one cell based on the redirection information.

[0008] According to another embodiment of the present disclosure, a method may include: receiving, by a base station, from a terminal a first random access channel (RACH) for a request for an on-demand system information block (SIB) of a first cell; transmitting, by the base station, to the terminal a first response message including redirection information for at least one cell or at least one frequency band; and receiving, by the base station, from the terminal a second RACH for an on-demand SIB request for a second cell associated with a first frequency band of the at least one frequency band or a third cell of the at least one cell, based on the redirection information.

[0009] According to various embodiments of the present disclosure, a method and apparatus for performing uplink transmission and reception in a wireless communication system can be provided.

[0010] According to various embodiments of the present disclosure, a method and apparatus for performing a redirection procedure related to an on-demand SIB1 may be provided.

[0011] By various embodiments of the present disclosure, the possibility of failure during initial connection can be reduced by allowing a terminal to attempt initial connection to an appropriate cell while requesting on-demand SIB1.

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

[0013] 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.

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

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

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

[0017] 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.

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

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

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

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

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

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

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

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

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

[0027] FIG. 15 illustrates an example of cell DTX / DRX operation to which some examples of the present disclosure may be applied.

[0028] FIG. 16 illustrates an example of carrier aggregation (CA) operation including an SSB-less cell to which some examples of the present disclosure may be applied.

[0029] FIG. 17 illustrates an example of a conditional handover operation to which some examples of the present disclosure may be applied.

[0030] FIG. 18 illustrates an example of a procedure for CSI measurement and reporting to which some examples of the present disclosure may be applied.

[0031] FIG. 19 illustrates an example of an on-demand SIB1 transmission procedure to which some examples of the present disclosure may be applied.

[0032] FIG. 20 illustrates an SSB transmission method of a base station operating multiple frequency bands applicable to the present disclosure.

[0033] FIG. 21 is a flowchart for explaining the operation of a terminal according to one embodiment of the present disclosure.

[0034] FIG. 22 is a flowchart for explaining the operation of a base station according to one embodiment of the present disclosure.

[0035] 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.

[0036] 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.

[0037] 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.

[0038] In this disclosure, terms such as “first,” “second,” etc. are used only to distinguish one component from another and are not used to limit the components, and do not limit the order or importance between the 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.

[0039] The terminology used in this disclosure is for the purpose of describing particular embodiments only 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.

[0040] 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."

[0041] 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."

[0042] 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.”

[0043] 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.”

[0044] 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."

[0045] In the following description, 'when, if, in case of' can be replaced with 'based on'.

[0046] Technical features individually described in one drawing in this disclosure may be implemented individually or simultaneously.

[0047] 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.

[0048] In the present disclosure, a base station (BS) may be a second node / IAB node / Transmission-Reception Point (TRP).

[0049] 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.

[0050] 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.

[0051] 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.

[0052] 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), and 5G NR.

[0053] 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.

[0054] Network structure

[0055] Figure 1 illustrates a flexible network topology to which some examples of the present disclosure may be applied.

[0056] 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.

[0057] 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.

[0058] 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.

[0059] 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.

[0060] 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.

[0061] 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.

[0062] Systems applicable to this disclosure

[0063] FIG. 2 illustrates an example of a communication system to which some examples of the present disclosure may be applied.

[0064] 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).

[0065] 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).

[0066] 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.

[0067] Device applicable to the present disclosure

[0068] FIG. 3 illustrates an example of a wireless device to which some examples of the present disclosure may be applied.

[0069] 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).

[0070] 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.

[0071] 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.

[0072] 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 driven 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.

[0073] 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.

[0074] 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.

[0075] 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).

[0076] 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.

[0077] 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.

[0078] 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.

[0079] 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.

[0080] 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.

[0081] 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.

[0082] 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 backhaul communications, and a wired transceiver may not be included.

[0083] Communication procedures

[0084] 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.

[0085] 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.

[0086] 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).

[0087] 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., the 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.

[0088] 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)).

[0089] 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.

[0090] 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.

[0091] 6G system core technologies

[0092] 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.

[0093] artificial intelligence

[0094] 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. 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.

[0095] FIG. 5 illustrates a functional framework for AI operations to which some examples of the present disclosure may be applied.

[0096] Below, to explain AI (or AI / ML (machine learning)) in more detail, the terms can be defined as follows.

[0097] - Data collection: Data collected from network nodes, management entities, or terminals as a basis for AI model training, data analysis, and inference.

[0098] - 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.

[0099] - 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.

[0100] - AI / ML inference: The process of making predictions or inducing decisions based on collected data and the AI ​​model using a trained AI model.

[0101] Referring to FIG. 5, the data collection function (10) is a function that collects input data and provides processed input data to the model training function (20) and the model inference function (30).

[0102] Examples of input data may include measurements from terminals or other network entities, feedback from actors, and output from AI models.

[0103] The data collection function (10) performs data preparation based on input data and provides input data processed through the data preparation. Here, the data collection function (10) does not perform data preparation specific to each AI algorithm (e.g., data pre-processing and cleaning, formatting, and transformation), but can perform data preparation common to all AI algorithms.

[0104] After the data preparation process is performed, the data collection function (10) may provide training data (11) to the model training function (20) and may provide inference data (12) to the model inference function (30). Here, the training data (11) may correspond to data required as input for the AI ​​model training function (20), and the inference data (12) may correspond to data required as input for the AI ​​model inference function (30).

[0105] The data collection function (10) may be performed by a single entity (e.g., a terminal, a RAN node, a network node, etc.), but may also be performed by multiple entities. In this case, training data (11) and inference data (12) may be provided to the model training function (20) and model inference function (30), respectively, from multiple entities.

[0106] The model training function (20) may correspond to a function that performs AI model training, validation, and testing, which can generate model performance metrics as part of the AI ​​model testing procedure. If necessary, the model training function (20) may also be responsible for data preparation (e.g., data pre-processing and cleaning, formatting, and transformation, etc.) based on training data (11) provided by the data collection function (10).

[0107] Here, model deployment / update (13) can be used to initially deploy a trained, validated and tested AI model to the model inference function (30) or to provide an updated model to the model inference function (30).

[0108] The model inference function (30) may correspond to a function that provides AI model inference output (16) (e.g., prediction or decision). If applicable, the model inference function (30) may provide model performance feedback (14) to the model training function (20). In addition, the model inference function (30) may also be responsible for data preparation (e.g., data pre-processing and cleaning, formatting and transformation, etc.) based on inference data (12) provided by the data collection function (10), if necessary.

[0109] Here, output (16) refers to the inference output of the AI ​​model generated by the model inference function (30), and the details of the inference output may vary depending on the use case.

[0110] Model performance feedback (14) can be used to monitor the performance of the AI ​​model, if available, and this feedback may be omitted.

[0111] An actor function (40) is a function that receives an output (16) from a model inference function (30) and triggers or performs a corresponding task / action. The actor function (40) can trigger tasks / actions for other entities (e.g., one or more terminals, one or more RAN nodes, one or more network nodes, etc.) or for itself.

[0112] Feedback (15) can be used to derive training data (11), inference data (12), or to monitor the performance of the AI ​​model, its impact on the network, etc.

[0113] Meanwhile, the definitions of training / validation / test in data sets used in AI / ML can be distinguished as follows.

[0114] - Training data: refers to a data set for learning a model.

[0115] - Validation data: This refers to a dataset used to validate a model that has already completed training. Validation data can typically be used to prevent overfitting of the training data set. It can also be used to select the best model among the various models learned during the training process. Therefore, validation can be considered a type of learning.

[0116] - Test data: This refers to the data set for final evaluation. This data is unrelated to learning.

[0117] For example, the training and validation data can be divided into an 8:2 or 7:3 ratio within the entire data set. Alternatively, the training data:validation data:test data can be divided into a 6:2:2 ratio within the entire data set.

[0118] The level of cooperation can be defined as follows depending on whether the base station and the terminal have capabilities for AI / ML functions, and variations due to combination of multiple levels or separation of any one level are also possible.

[0119] Category 0a: This category corresponds to a no-collaboration framework. In this case, AI / ML algorithms are purely implementation-based and may not require any changes to the wireless interface.

[0120] Category 0b: Frameworks that involve a wireless interface modified to fit efficient implementation-based AI / ML algorithms, but without collaboration.

[0121] Category 1: This category applies to cases where inter-node support is required to improve the AI / ML algorithms of each node. For example, this applies when a terminal receives support from a base station (for training, adaptation, etc.), and vice versa. At this level, model exchange between network nodes is not required.

[0122] Category 2: This applies to cases where joint ML tasks can be performed between terminals and base stations. This level requires exchange of AI / ML model commands or network nodes.

[0123] The functions exemplified in FIG. 5 above may be implemented in a RAN node (e.g., a base station, a TRP, a CU of a base station, etc.), a network node, an OAM (operation administration maintenance) of a network operator, or a terminal.

[0124] Alternatively, two or more entities, such as a RAN, a network node, a network operator's OAM, or a terminal, may cooperate to implement the functions illustrated in FIG. 5. For example, one entity may perform some of the functions of FIG. 5, and another entity may perform the remaining functions. In this way, since some of the functions illustrated in FIG. 5 are performed by a single entity (e.g., a terminal, a RAN node, a network node, etc.), the transmission / provision of data / information between each function may be omitted. For example, if the model training function (20) and the model inference function (30) are performed by the same entity, the transmission / provision of model deployment / update (13) and model performance feedback (14) may be omitted.

[0125] Alternatively, any one of the functions illustrated in FIG. 5 may be performed collaboratively by two or more entities, including a RAN, a network node, a network operator's OAM, or a terminal. This may be referred to as a split AI operation.

[0126] FIG. 6 illustrates an example of operations related to AI model training and AI model inference to which some examples of the present disclosure may be applied.

[0127] For example, the AI ​​model training function may be performed by a network node (e.g., a core network node, an OAM of a network operator, etc.), and the AI ​​model inference function may be performed by a RAN node (e.g., a base station, a TRP, a CU of a base station, etc.).

[0128] Step 1: RAN node 1 and RAN node 2 can transmit input data (e.g., training data) for AI model training to the network node. Here, RAN node 1 and RAN node 2 can also transmit data collected from the terminal (e.g., terminal measurements related to RSRP (reference signal received power), RSRQ (reference signal received quality), SINR (signal to interference-plus-noise ratio) of the serving cell and neighboring cells, terminal location, speed, etc.) to the network node.

[0129] Step 2: Network nodes can train AI models using the received training data.

[0130] Step 3: The network node may distribute / update the AI ​​model to RAN node 1 and / or RAN node 2. RAN node 1 (and / or RAN node 2) may also continue model training based on the received AI model.

[0131] For convenience of explanation, we assume that the AI ​​model is deployed / updated only to RAN node 1.

[0132] Step 4: RAN node 1 can receive input data (e.g., inference data) for AI model inference from the terminal and RAN node 2.

[0133] Step 5: RAN node 1 can perform AI model inference using the received inference data to generate output data (e.g., prediction or decision).

[0134] Step 6: If applicable, RAN node 1 may send model performance feedback to the network nodes.

[0135] Step 7: RAN node 1, RAN node 2, and the terminal (or 'RAN node 1 and the terminal', or 'RAN node 1 and RAN node 2') may perform actions based on the output data. For example, in the case of a load balancing operation, the terminal may move from RAN node 1 to RAN node 2.

[0136] Step 8: RAN node 1 and RAN node 2 can transmit feedback information to the network nodes.

[0137] FIG. 7 illustrates another example of operations related to AI model training and AI model inference to which some examples of the present disclosure may be applied.

[0138] For example, both AI model training functions and AI model inference functions can be performed by RAN nodes (e.g., base stations, TRPs, CUs of base stations, etc.).

[0139] Step 1: The terminal and RAN node 2 can transmit input data (e.g., training data) for AI model training to RAN node 1.

[0140] Step 2: RAN node 1 can train an AI model using the received training data.

[0141] Step 3: RAN node 1 can receive input data (e.g., inference data) for AI model inference from the terminal and RAN node 2.

[0142] Step 4: RAN node 1 can perform AI model inference using the received inference data to generate output data (e.g., prediction or decision).

[0143] Step 5: RAN node 1, RAN node 2, and the terminal (or 'RAN node 1 and the terminal', or 'RAN node 1 and RAN node 2') may perform actions based on the output data. For example, in the case of a load balancing operation, the terminal may move from RAN node 1 to RAN node 2.

[0144] Step 6: RAN node 2 may transmit feedback information to RAN node 1.

[0145] FIG. 8 illustrates another example of operations related to AI model training and AI model inference to which some examples of the present disclosure may be applied.

[0146] For example, the AI ​​model training function may be performed by a RAN node (e.g., a base station, a TRP, a CU of a base station, etc.), and the AI ​​model inference function may be performed by a terminal.

[0147] Step 1: The terminal may transmit input data (e.g., training data) for AI model training to the RAN node. Here, the RAN node may collect data (e.g., terminal measurements related to RSRP, RSRQ, SINR of the serving cell and neighboring cells, terminal location, speed, etc.) from various terminals and / or from other RAN nodes.

[0148] Step 2: RAN nodes can train AI models using the received training data.

[0149] Step 3: The RAN node can distribute / update the AI ​​model to the terminal. The terminal can also continue model training based on the received AI model.

[0150] Step 4: Input data (e.g., inference data) for AI model inference can be received from the terminal and RAN node (and / or from another terminal).

[0151] Step 5: The terminal can perform AI model inference using the received inference data to generate output data (e.g., prediction or decision).

[0152] Step 6: If applicable, the terminal may send model performance feedback to the RAN node.

[0153] Step 7: The terminal and RAN node can perform actions based on the output data.

[0154] Step 8: The terminal may transmit feedback information to the RAN node.

[0155] THz communication (terahertz communication)

[0156] 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.

[0157] FIG. 9 illustrates an electromagnetic spectrum to which some examples of the present disclosure may be applied.

[0158] 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.

[0159] 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.

[0160] FIG. 10 illustrates an example of a system information transmission / reception procedure to which some examples of the present disclosure may be applied.

[0161] The example of Fig. 10 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. 10 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. 10.

[0162] In step S1010, the second node (120) (e.g., base station) can transmit system information of cell #1 via 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.

[0163] At step S1030, the first node (110) (e.g., terminal) can acquire synchronization for cell #1. Synchronization can be acquired by detecting a synchronization signal. Typically, synchronization is acquired before receiving system information, but 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.

[0164] At step S1050, 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.

[0165] The procedure described with reference to FIG. 10 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) hands over to cell #1 of the second node (120). However, in the case of 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).

[0166] 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 times may be required, resulting in link instability.

[0167] FIG. 11 exemplarily illustrates a beam management procedure to which some examples of the present disclosure may be applied.

[0168] Although FIG. 11 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.

[0169] 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.

[0170] In step S1110, the second node (120) (e.g., base station) can set resources for beam management to the first node (110) (e.g., terminal). Here, the resources can include at least one of time-frequency resources, channels, and spatial resources (e.g., antenna ports). For example, the base station can utilize a beam search signal (BSS) that is transmitted spatially separated from an existing downlink signal / channel for beam search. Here, the BSS can be transmitted based on a dedicated port for beam search. The dedicated port can 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 can be included in the technical concept according to the present embodiment.

[0171] In step S1130, the second node (120) (e.g., 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).

[0172] In step S1050, 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 in step S1030.

[0173] In step S1070, the first node (110) and the second node (120) can perform communication. For example, the second node (120) can perform transmission to the first node (110) using the 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).

[0174] non-terrestrial networks (NTN)

[0175] Figures 12 and 13 illustrate examples of NTN scenarios to which some examples of the present disclosure may be applied.

[0176] NTN can represent a network or network segment that uses radio frequency (RF) resources mounted on a satellite (or unmanned aerial system (UAS) platform).

[0177] Figure 12 shows an example of a typical scenario of NTN based on transparent payload, and Figure 13 shows an example of a typical scenario of NTN based on regenerative payload.

[0178] Referring to Figure 12, 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.

[0179] Referring to Figure 13, 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.

[0180] Figures 12 and 13 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.

[0181] 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.

[0182] 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).

[0183] Integrated Sensing and Communication (ISAC)

[0184] 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.

[0185] FIG. 14 illustrates examples of sensing operations to which some examples of the present disclosure may be applied.

[0186] Specifically, Fig. 14(a) shows an example of a monostatic sensing operation using a sensing receiver and a sensing transmitter located in the same location. Fig. 14(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 through an entity / service within the 3GPP system.

[0187] Network Energy Saving (NES)

[0188] Energy conservation at base stations is a key consideration in wireless communication systems, including 3GPP, as it can contribute to building eco-friendly networks by reducing carbon emissions and reducing operational expenditures (OPEX) for telecommunications providers. In particular, the introduction of 5G communications will require higher transmission rates, necessitating base stations to be equipped with more antennas and provide services over wider bandwidths and frequency bands. Consequently, recent studies have shown that base station energy costs have reached as high as 20% of total OPEX. For example, various technologies for reducing energy consumption in 5G wireless communication systems are being discussed under the umbrella term network energy savings (NES).

[0189] Depending on the application of NES technology, the base station can perform operations such as controlling on / off for a certain time duration in the time domain, controlling transmission / reception resources for terminal-common or terminal-specific signals / channels, changing the amount of frequency domain resources, controlling transmission power, or turning on / off an antenna port, transmission-reception point (TRP), etc. in the spatial domain.

[0190] For example, a base station may identify the NES solution(s) to be applied, perform signaling to the NES, and perform actions on the NES.

[0191] NES solution(s) may be related to control of signal transmission and reception (e.g., on / off), beam operation, handover procedures, channel measurement, and reporting. The NES solution(s) to be applied may be adaptively selected or predefined based on current conditions (e.g., cell load level, characteristics of connected terminals, etc.).

[0192] A base station that has identified NES solution(s) performs signaling for the NES. The specific signaling procedure may vary depending on the identified NES solution(s). For example, the base station may transmit common information about the NES solution(s), transmit configuration information necessary for NES operation to at least one terminal, or transmit control information regarding the progress of NES operation to at least one terminal. In addition, the base station may receive capability information related to the NES from at least one terminal.

[0193] Based on the signaled NES-related information, the base station can perform operations for the NES. For example, based on system information, configuration information, and control information conveyed via signaling, the base station can turn on / off transmission and reception of specific signals, turn on / off elements in the spatial domain, or adjust resources for transmission and reception of measurement signals.

[0194] Examples of NES solutions that can be implemented using these procedures include:

[0195] Intra-system energy saving: A RAN node may request a neighboring RAN node to switch at least one SSB beam into its inactive cell, or may perform paging using a limited set of beams to an inactive terminal (e.g., a stationary terminal).

[0196] Inter-system energy savings: NG-RAN nodes that own capacity booster cells can autonomously transition those cells to an inactive state.

[0197] SSB-less cells: If SSB or SSB-based RRM (radio resource management) measurement timing configuration (SMTC) configuration is not provided for a specific cell (e.g., secondary cell (SCell) or primary cell (PCell)), the UE may obtain timing reference and automatic gain control (AGC) source from another serving cell. In frequency range 1 (FR1) or FR2, the base station may configure intra-band carrier aggregation (CA) or inter-band CA including cells without SSB transmission, in which case SSB / SIB transmission may be triggered by a wake up signal (WUS) of the UE. Accordingly, since the period of common channels / signals such as SSB is increased, the base station may stay in sleep state for a longer time.

[0198] Cell DTX (discontinuous transmission) / DRX (discontinuous reception): In order to reduce the downlink transmission / uplink reception activity time of the base station, a periodic cell DTX / DRX pattern (e.g., active and inactive periods) may be commonly configured for terminals within a cell having the feature. Here, the cell DTX pattern and the cell DRX pattern may be configured and activated separately, and up to two cell DTX / DRX patterns may be configured per MAC entity. When cell DTX is configured and activated, at least one of monitoring for a semi-persistent scheduling (SPS) opportunity or monitoring a PDCCH may be stopped during the cell DTX inactivity period. When cell DRX is configured and activated, at least one of transmission on a configured grant (CG) resource or transmission of a scheduling request (SR) may be stopped during the cell DRX inactivity period. Cell DTX / DRX can be activated / deactivated via RRC signaling or L1 (layer 1) group common signaling.

[0199] Parameters such as active duration and cycle may be configured for cell DTX / DRX. Active duration is the period during which the UE receives a PDCCH or SPS opportunity and waits to transmit SR or CG, and cycle may specify the periodic repetition of the active duration and inactive duration. When both cell DTX and cell DRX are configured, parameters such as active duration and cycle may be common. If the base station recognizes an emergency call or a public safety-related service (e.g., multimedia priority service (MPS) or mission critical service (MCS)), the network may release or deactivate the cell DTX / DRX configuration so as not to affect the service. In addition, at least some overlap may be required between the active period of the connected mode DRX of the UE and the active period of the cell DTX / DRX. For example, the connected mode DRX cycle of the UE may be a multiple of the cell DTX / DRX cycle, or vice versa.

[0200] Conditional handover (CHO): A CHO procedure performed in a manner in which the execution of a handover is determined by the UE may be used while NES technology is applied (e.g., when the cell activates or deactivates cell DTX / DRX). In this case, the UE may use an NES-specific CHO event to initiate CHO to a candidate cell, and reception of a DCI activating the CHO condition(s) set by the NES event indication may be applied as an additional triggering condition for this.

[0201] Spatial and Power Domain Adaptation: To support the base station for transceiver muting and / or transmit power adaptation, the UE may be configured to report multiple CSI quantities in a CSI report based on multiple sub-configurations. Each sub-configuration corresponds to a spatial domain adaptation pattern (e.g., a subset of available spatial elements) and / or a power offset between a data channel (e.g., PDSCH) and CSI-RS. Depending on the application of the spatial and power domain adaptation solution, the CSI configuration, measurement, and / or reporting behavior may be affected.

[0202] Cell DTX / DRX

[0203] To enable base stations to operate in sleep mode for relatively long periods of time without frequent wake-ups, base station DTX / DRX has been introduced for NES purposes. The base station can reduce energy consumption by utilizing DTX transmission under low system load conditions by configuring cell DTX and setting the on-duration of terminals' C-DRX within the active period of the cell DTX.

[0204] FIG. 15 illustrates an example of cell DTX / DRX operation to which some examples of the present disclosure may be applied.

[0205] A second node (120) (e.g., a base station) can transmit system information to a first node (110) (e.g., a terminal). Accordingly, the first node (110) can check information related to the cell DTX / DRX of the second node (120).

[0206] For example, system information may include MIB, SIB1, etc. In relation to NES technology, MIB may include information related to cell barring (e.g., cellBarred), and SIB1 may include information related to cell barring state (e.g., cellBarredNES). For example, if cellBarred included in MIB is set to a value indicating that it is not barred (e.g., notBarred), a terminal may determine that the cell is not barred, regardless of whether it supports NES cell DTX / DRX. For example, if cellBarred included in received MIB is set to a value indicating that the cell is barred (e.g., barred), a terminal that does not support NES cell DTX / DRX may determine that the cell is barred.

[0207] For example, if a terminal has a capability to support NES cell DTX / DRX, the terminal can check SIB1 to determine a cell barring status. For example, if cellBarred of MIB is set to barred and cellBarredNES is absent in SIB1, a terminal supporting NES cell DTX / DRX can treat the cell as barred and perform cell reselection to another cell. For example, if cellBarred of MIB is set to barred and cellBarredNES is included in SIB1, a terminal supporting NES cell DTX / DRX can determine that the cell is not barred.

[0208] In the example of FIG. 15, it is assumed that the terminal has the capability to support NES cell DTX / DRX, and cellBarred of MIB is set to notBarred, or cellBarred of MIB is set to barred and SIB1 includes cellBarredNES. Accordingly, the terminal can perform a random access procedure to connect to the base station, and then perform communication. For example, the base station can perform a cell DTX / DRX operation, and transmit configuration information related to the cell DTX / DRX operation to the terminal. The configuration information related to the cell DTX / DRX operation (e.g., CellDTXDRX-Config) includes at least one parameter related to the cell DTX / DRX, and may include, for example, at least one of an on-duration timer, a cycle start offset, a slot offset, a configuration type (e.g., DTX, DRX, or DTX-DRX), and an activation state of the DTX / DRX (e.g., active, inactive). Additionally, the configuration information may further include information for receiving and interpreting cell DRX / DRX-related control information (e.g., cellDTRX-RNTI included in physicalCellGroupConfig, DCI-related information such as the size of DCI format 2_9, etc.).

[0209] Thereafter, the base station can transmit control information related to cell DTX / DRX to the terminal. The control information related to cell DTX / DRX can include DCI having a designated format (e.g., DCI format 2_9). If an operation for a serving cell according to at least one of a cell DTX operation and a cell DRX operation is configured by configuration information (e.g., cellDTXDRX-Config included in secvingcell-config), the terminal can check a set of search spaces (e.g., a Type3-PDCCH CSS set) for monitoring a PDCCH conveying control information of a designated format during an active time through a higher layer parameter (e.g., SearchSpace included in PDCCH-Config), and can obtain a location of information about the serving cell within the control information through a higher layer parameter (e.g., positionInDCI-cellDTRX included in SecvingCell-config). Then, the terminal can obtain control information based on the identified set of search spaces and the location.

[0210] Control information related to cell DTX / DRX may be used to indicate activation or deactivation of cell DTX and / or cell DRX, and / or to provide NES-mode indicators (e.g., NES-specific CHO execution conditions, etc.), and may include, for example, at least one block including a cell DTX / DRX indicator and an NES-mode indicator. In this case, when the serving cell is configured as a supplementary uplink (SUL) carrier, the indication of activation or deactivation of cell DRX by the cell DTX / DRX indicator may be applied to both the uplink (UL) carrier and the SUL carrier.

[0211] After that, the terminal and the base station can perform communication based on the cell DTX / DRX. Specifically, the base station can turn on / off the transmission and reception of signals according to the settings related to the cell DTX / DRX, so that the terminal can selectively monitor the signal from the base station. During the DTX-OFF duration, the base station can enter a sleep mode to reduce energy consumption. For example, the base station DTX cycle can be aligned with the cycle of the terminal DRX. The base station DTX-ON duration can completely cover the DRX-ON duration of the terminal. Furthermore, the base station can align the transmission on Xn (base station-to-base station interface) / NG (interface between 5G RAN and 5G core network) and the transmission on Uu (interface between terminal and network) for NES purposes. The DTX / DRX mechanism triggers switching of reference signal resource sets, and the base station can perform a dormancy-like behavior of rarely or not transmitting SSB, SIB, and CSI-RS to reduce energy consumption. The terminal can rarely or not receive downlink signals / channels depending on the configuration of the base station. Once the base station DTX / DRX operation is triggered, the terminal can discontinuously receive the corresponding CSI-RS, SSB, or PDCCH during the DTX / DRX OFF duration.

[0212] SSB-less cells

[0213] FIG. 16 illustrates an example of carrier aggregation (CA) operation including an SSB-less cell to which some examples of the present disclosure may be applied.

[0214] In the example of Figure 16, it is assumed that the SSB-less cell is an SCell in the CA, but the SSB-less cell may also be a PCell in the CA.

[0215] A second node (120) (e.g., a base station) can transmit configuration information for an SCell to a first node (110) (e.g., a terminal). For example, the base station can transmit configuration information for CA to provide a service to the terminal through a CA operation. Here, the CA operation may be an intra-band CA or an inter-band CA. For example, the configuration information for an SCell may include information (e.g., sCellToAddModList) including information for adding an SCell, and specifically, may include a cell index, a physical cell identifier, information related to DL-UL configuration, information related to BWP, information related to cell DTX / DRX, information related to downlink frequency (e.g., FrequencyInfoDL), etc. Accordingly, the terminal can determine the configuration for the CA operation and perform communication using the PCell and SCell of the base station.

[0216] For example, the terminal can determine that the SCell is an SSB-less SCell based on information related to the downlink frequency included in the configuration information, and can check related parameters. For example, the terminal can determine that the SCell is an SSB-less SCell by checking the presence of a parameter indicating that the SCell is an SSB-less SCell (e.g., SSBlessSCell), and can check the timing reference and AGC source for the SCell based on information about the reference cell (e.g., referenceCell). In the example of Fig. 16, the reference cell can be the PCell. Therefore, the terminal can use the PCell as a timing reference and AGC source for communication in the SCell. For example, the reference of the SSB-less cell can be (another) cell, TRP, CORESET pool (control resource set pool), (additional) PCI (physical cell ID), etc.

[0217] Conditional Handover (CHO)

[0218] FIG. 17 illustrates an example of a conditional handover operation to which some examples of the present disclosure may be applied.

[0219] The order of the operations illustrated in Fig. 17 may vary depending on the case.

[0220] A second node (120) (e.g., a base station) can transmit configuration information for CHO to a first node (110) (e.g., a terminal). The configuration information for CHO can include information related to conditional reconfiguration (e.g., ConditionalReconfiguration, CondReconfigToAddModList), information related to configuration for reporting (e.g., ReportConfigNR). For example, the information related to configuration for reporting can include information related to events related to reporting, identifiers of the events (e.g., condEventId), information indicating whether it is a NES-specific CHO event (e.g., nesEvent), etc. In the example of FIG. 17, it is assumed that event information indicating that it is a NES-specific CHO event is received.

[0221] A base station may transmit information for enabling an NES-specific CHO execution condition to a terminal. The information for enabling the NES-specific CHO execution condition may be transmitted via control information of a specified format (e.g., DCI format 2_9). The information for enabling the NES-specific CHO execution condition may be referred to as an NES-mode indicator, and may be, for example, 1-bit information that indicates enabling the NES-specific CHO execution condition when a related upper layer parameter (e.g., nesEvent) is set and a serving cell of a related block in the DCI is a primary cell.

[0222] Afterwards, the terminal can perform measurements and transmit a measurement report to the base station. The base station can determine a CHO based on the measurement report and perform signaling for a handover request with the adjacent / neighboring base station(s) indicated by the measurement report. The base station can determine the adjacent base station(s) that have confirmed admission through signaling as candidate base station(s) and transmit information about the candidate base station(s) to the terminal. Accordingly, the terminal can evaluate the CHO execution conditions for the candidate base station(s). Based on the evaluation result, if a candidate cell satisfying the conditions is determined, the terminal can perform detachment for the old cell and synchronization for the new cell.

[0223] For example, based on event information indicating that the event is an NES-specific CHO event received by the terminal in the previous procedure and information enabling an NES-specific CHO execution condition, the terminal can determine whether the event is satisfied. For example, if an NES-mode indicator is received through a lower layer and conditional triggering configuration information (e.g., condTriggerConfig) includes information indicating that the event is an NES-specific CHO event (e.g., nesEvent), the terminal can determine that the event associated with the corresponding measurement identifier (e.g., measId) is satisfied, and thus, determine that the CHO execution condition is satisfied.

[0224] Channel State Information (CSI) Measurement and Reporting

[0225] FIG. 18 illustrates an example of a procedure for CSI measurement and reporting to which some examples of the present disclosure may be applied.

[0226] A second node (120) (e.g., a base station) can transmit configuration information for CSI to a first node (110) (e.g., a terminal). The configuration information for CSI can include information related to a reference signal (e.g., a CSI-RS) resource or a resource set for CSI (e.g., time-frequency resource information, sequence information, power information, etc.), information related to CSI reporting (e.g., report item (quantity) information, report type information, report resource information, codebook information, etc.), information related to CSI measurement, etc.

[0227] For example, to assist the base station with transceiver muting and / or transmit power adaptation of the base station, the terminal may be configured to report multiple CSI entries in a CSI report based on multiple sub-configurations. For example, each sub-configuration may correspond to a spatial domain adaptation pattern (e.g., a subset of available spatial elements) and / or a power offset. With respect to CSI reporting, a higher layer parameter included in the configuration information (e.g., CSI-ReportConfig) may include a list of sub-configurations, and each sub-configuration may be identified by an identifier (e.g., csi-ReportSubConfigID). For example, each sub-configuration may correspond to a list of at least one CSI-RS resource, or may correspond to a subset of CSI-RS antenna ports, and / or may correspond to power-related parameters of the CSI-RS resource(s) (e.g., power control offset-related parameters (e.g., powerControlOffset) and / or power offset for a PDSCH associated with the CSI-RS).

[0228] For example, an information element (IE) for an aperiodic trigger state list for CSI may include a trigger list parameter for a CSI reporting sub-configuration. This parameter may include a list of sub-configuration ID(s) of N sub-configuration(s) among L configured sub-configurations within a CSI reporting configuration that are associated with triggering states for aperiodic CSI reporting on an uplink data channel (e.g., a physical uplink shared channel (PUSCH)).

[0229] For example, an IE for a CSI reporting configuration may include parameters for a list of CSI reporting sub-configuration ID(s) to be added / modified or released. Port subset indicators and a list of non-zero power (NZP) CSI-RS resources may not be configured simultaneously in the same CSI reporting configuration.

[0230] For example, an IE for a CSI reporting sub-configuration may include a port-subset indicator parameter, an NZP CSI-RS resource list parameter, and a power offset parameter.

[0231] The port-subset indicator parameter may indicate the number of ports of the NZP CSI-RS resources indicated in the NZP CSI-RS resource list (the value of which is equal to the number of ports of the corresponding NZP CSI-RS resources) and the (sub)set of CSI-RS antenna ports used for CSI calculation of the sub-configuration. Each bit in the bit string of the port-subset indicator corresponds to an antenna port, and if any bit is set to 1, the corresponding port may be enabled for CSI calculation corresponding to the sub-configuration, and if any bit is set to 0, the corresponding port may not be enabled for CSI calculation corresponding to the sub-configuration.

[0232] The NZP CSI-RS resource list parameter may indicate a list of NZP CSI-RS resources for a sub-configuration, which is a (sub)set of NZP CSI-RS resource(s) of a CSI-RS resource set for channel measurements associated with a sub-configuration of a CSI reporting configuration. The values ​​0, 1, 2, ... may mean the first, second, third, ... NZP CSI-RS resource of the CSI-RS resource set.

[0233] When the power offset parameter is set for an NZP CSI-RS resource, it may indicate that a power offset is applied between the PDSCH RE (resource element) and the NZP CSI-RS RE by the difference in the value of the power offset parameter from the value of the power control offset parameter.

[0234] When a configuration for CSI includes multiple sub-configurations, when interpreting the configuration information for CSI, the terminal may determine CSI-RS resources, CSI-RS port mapping, power offset, codebook type, report items, etc. by considering the sub-configurations. When configuration information related to CSI reporting including sub-configurations (e.g., CSI-ReportConfig) is provided to the terminal, the terminal may not expect that a higher layer parameter related to a report item (e.g., reportQuantity) is set to 'cri-RSRP', 'cri-SINR', 'cri-SINR-Index', 'cri-RSRP-Index', 'none', 'ssb-Index-RSRP', 'ssb-Index-SINR', 'ssb-Index-RSRP-Index', 'ssb-Index-SINR-Index' or 'tdcp' (wherein CRI corresponds to a CSI-RS resource index, and tdcp corresponds to time domain channel properties). Additionally, when the type of CSI reporting is set to semi-persistent CSI reporting or aperiodic CSI reporting, the base station can activate / trigger only some of the sub-configurations configured for the UE through MAC-CE (control element) or DCI (downlink control information). For example, the trigger state of aperiodic CSI reporting can be configured as needed, and whether semi-static CSI reporting is activated can be controlled by an activation command.

[0235] For example, with respect to the configuration of a report quantity, the terminal may determine the CSI-RS port index(es) for each CSI-RS resource based on information related to a port subset per sub-configuration (hereinafter referred to as a "port subset indicator"). The port subset indicator may include a bitmap for specifying some of the antenna ports for the corresponding CSI-RS resource. Accordingly, the terminal may identify at least one antenna port for the corresponding sub-configuration based on the positions of bits set to positive values ​​(e.g., 1) in the port subset indicator.

[0236] For example, with respect to the configuration of report items (report quantity), the terminal may determine the codebook type based on the presence or absence of sub-configurations. Specifically, if sub-configurations are configured for CSI reporting, the terminal may exclude the configuration of at least one codebook type. For example, if the terminal's capabilities support it, at least one codebook type may be configured.

[0237] For example, in relation to the configuration of the report quantity, a power offset value and an NZP CSI-RS resource set may be configured for each sub-configuration. For example, depending on whether a power offset value is configured for each sub-configuration and whether an NZP CSI-RS resource set is configured, the interpretation of the NZP CSI-RS resource set for each sub-configuration may vary.

[0238] When determining the channel quality indicator (CQI), a higher-layer parameter related to time restrictions for channel measurements (e.g., timeRestrictionForChannelMeasurements) may be configured. In this case, the terminal can derive a channel estimate for determining CSI based on the most recent CSI reference resource. For example, if cell DTX is activated for the base station, the cell DTX activation time, etc., may be considered to determine the CSI reference resource, etc.

[0239] CSI is derived based on CSI reference resources. A CSI reference resource is defined as a group of downlink physical resource blocks corresponding to a band related to the CSI derived in the frequency domain, and is defined as a single downlink slot determined based on higher-layer parameters and subcarrier spacing in the time domain. After receiving a CSI-RS, a UE can transmit a CSI report no later than the CSI reference resource. For example, if sub-configurations are configured for a CSI report, a CSI reference resource may be considered for each sub-configuration.

[0240] When at least one of a CQI index, a precoding matrix index (PMI), and a rank indicator (RI) is set to be reported, in the CSI reference resource, the terminal may assume specific values ​​for the symbol positions and number occupied by control signaling, the number of PDSCH and demodulation reference signal (DMRS) symbols, the subcarrier spacing of the bandwidth part (BWP), the bandwidth for CQI reporting, the length and subcarrier spacing of the cyclic prefix (CP) of the reference resource, and the redundancy version (RV), for the purpose of deriving at least one of the CQI index, PMI, and RI. At this time, when sub-configurations are set for the CSI reporting, assumptions about the antenna port, EPRE (energy per resource element), etc. may be determined based on the sub-configurations.

[0241] Based on the aforementioned configuration, the base station can transmit at least one CSI-RS to the terminal. Based on the aforementioned configuration, the terminal can receive at least one CSI-RS and perform measurement on it. For example, the at least one CSI-RS can be transmitted via a CSI-RS resource or resource set configured by the configuration information.

[0242] When the terminal is set to DRX (discontinuous reception), the terminal can perform measurements as follows. For example, when the terminal is set to monitor power saving related control information (e.g., DCI format 2_6) and the DRX related timer (e.g., drx-onDurationTimer) has not been started by a higher layer parameter (e.g., ps-TransmitOtherPeriodicCSI), and is set to report CSI using a reporting configuration type set to periodic reporting and a reporting item set to an item other than cri-RSRP and ssb-index-RSRP, the most recent CSI measurement opportunity occurs during the time indicated by drx-onDurationTimer in the DRX related configuration information (e.g., DRX-Config) other than the DRX active time or the DRX active time for the CSI to be reported. As another example, if the terminal is configured to monitor power saving related control information (e.g., DCI format 2_6) and is configured to report L1-RSRP using a report configuration type set to periodic reporting and a report item set to cri-RSRP in a situation where drx-onDurationTimer has not started by a higher layer parameter (e.g., ps-TransmitPeriodicL1-RSRP), the most recent CSI measurement opportunity occurs during a time indicated by drx-onDurationTimer in DRX-related configuration information (e.g., DRX-Config) other than the DRX active time or the DRX active time for the CSI to be reported. In addition, the most recent CSI measurement opportunity occurs within the DRX active time for the CSI to be reported.

[0243] A base station may perform cell DTX and / or cell DRX operations. In this case, during the inactive period of cell DTX, a terminal configured as cell DTX may not expect to receive periodic CSI-RS and semi-static CSI-RS, at least as configured in a CSI reporting configuration associated with a report item including RI. When cell DTX is activated for a serving cell, the most recent CSI measurement opportunity of a semi-static CSI-RS resource or a periodic CSI-RS resource may occur within the active periods of cell DTX for CSI reporting, at least as configured by configuration information (e.g., CSI-ReportConfig) related to CSI reporting associated with a report item including RI.

[0244] A terminal that receives at least one CSI-RS can determine CSI. For example, the terminal can perform CSI calculations. The terminal can perform CSI calculations based on CSI processing criteria. The terminal can indicate the number of supported concurrent CSI calculations, for example, the number of CSI processing units (CPUs) that can be performed simultaneously, called NCPUs. The terminal can determine the number of CPUs for a given CSI report based on at least one of the NCPUs, the number of CPUs for each CSI report, the number of CPUs currently occupied, and the settings of the report items. For example, for configuration information (e.g., CSI-ReportConfig) related to CSI reporting that includes a report item parameter (e.g., reportQuantity) that is not set to 'none', the CPU(s) may be occupied for at least one orthogonal frequency division multiplexing (OFDM) symbol, wherein the number of at least one symbol may be determined based on CSI-RS resources or CSI-IM (interference measurement) resources associated with the sub-configurations.

[0245] When configuration information related to CSI reporting (e.g., CSI-ReportConfig) includes multiple sub-configurations, the number of CPUs occupied by the CSI report may be determined based on the number of CSI-RS resources corresponding to the sub-configurations. For example, the number of CSI-RS resources may be determined based on the number of times they are referred in the configuration information related to CSI reporting (e.g., CSI-ReportConfig) or the number of sub-configurations referencing the corresponding CSI-RS resources.

[0246] A terminal that has determined CSI can transmit a CSI report to a base station. The terminal can transmit CSI(s) for at least one sub-configuration according to a report item parameter (e.g., reportQuantity) configured for configuration information related to the CSI report (e.g., CSI-ReportConfig). For example, the CSI report can include at least one of PMI, CQI, RI, CRI, SSBRI (SSB resource index), LI (layer indicator), and RSRP. In this case, the CSI report can include a Part 1 CSI report and a Part 2 CSI report. In addition, the CSI report can be transmitted via at least one of a physical uplink control channel (PUCCH) or a PUSCH.

[0247] When a terminal multiplexes a CSI report including a Part 2 CSI report on a PUCCH resource, the terminal determines the number of PUCCH resources and physical resource blocks (PRBs) for the PUCCH resource or the number of Part 2 CSI reports, assuming that each CSI report or each CSI sub-report included in the CSI report indicates rank 1 or the rank combination {1, 1}. When a higher layer parameter related to the CSI reporting mode (e.g., csi-ReportMode) is set to 'Mode2', the terminal determines the PUCCH resource and the number of PRBs for the PUCCH resource or the number of Part 2 CSI reports, assuming that each CRI of the CSI report is associated with a resource pair.

[0248] When a CSI report on PUSCH includes two parts, the UE may omit some of the Part 2 CSI. The omission of Part 2 CSI is in priority order. When omitting Part 2 CSI information for a particular priority level, the UE shall exclude all information for that priority level, except when the corresponding CSI report includes at least one CSI sub-report including Part 2, which corresponds to a sub-configuration from a list of sub-configurations provided by a higher layer parameter (e.g., csi-ReportSubConfigList) included in information related to the CSI report (e.g., CSI-ReportConfig).

[0249] For a report configuration related to information related to a CSI report (e.g., CSI-ReportConfig) that includes a list of sub-configurations, the following processing is possible: For a corresponding CSI report that includes at least one CSI sub-report, omission of Part 2 CSI is performed at the sub-configuration level within the same priority level, where a sub-configuration with a lower index value has a higher priority.

[0250] If a CSI report consists of two parts, a UE may omit some of the Part 2 CSI. The omission of Part 2 CSI is based on a priority order. For a report configuration related to information related to a CSI report (e.g., CSI-ReportConfig) that includes a list of sub-configurations, for a given CSI report that includes at least one CSI sub-report, the omission of Part 2 CSI may be applied according to the CSI reporting procedure using PUSCH. Part 2 CSI may be omitted starting from the lowest priority level up to the Part 2 CSI coding rate that is less than or equal to the coding rate set by the higher layer parameter (e.g., maxCodeRate).

[0251] Additionally, if the CQI request (or CSI request) field in the DCI triggers CSI report(s) on the PUSCH, the first uplink symbol carrying the CSI report(s) may not precede a symbol specified after a certain interval from the last symbol of the PDCCH carrying the corresponding DCI. Accordingly, the CSI calculation time may be guaranteed. For example, if multiple sub-configurations are configured for the CSI report, the starting position of the aforementioned certain interval may be determined based on all triggered sub-configurations.

[0252] CSI is transmitted via PUCCH or PUSCH and can be expressed as a bit string of a fixed size. When CSI is transmitted via PUCCH, if a parameter (e.g., csi-ReportSubConfig) indicating sub-configuration-specific settings for CSI reports is configured, the mapping order of CSI fields for each CSI sub-report can be applied according to predefined rules.

[0253] When CSI is transmitted via PUSCH, if a parameter indicating sub-configuration-specific configuration for CSI reporting (e.g., csi-ReportSubConfig) is set, for each CSI sub-report, the mapping order of CSI fields can be applied according to a predefined rule.

[0254] Some or all of the examples of FIGS. 1 to 18 described above may be combined with some or all of the examples of the present disclosure described below, and such combined examples are included within the scope of the present disclosure.

[0255] On-demand SSB transmission and reception procedures

[0256] In basic communication systems, base stations were defined to periodically transmit SSB for purposes such as time / frequency synchronization and / or radio resource management (RRM). In other words, base stations were defined to transmit SSB even when there was no data to transmit or receive, resulting in unnecessary energy consumption.

[0257] Accordingly, the base station can reduce energy consumption by transmitting SSB to the terminal on a specific cell according to the on-demand SSB procedure and not transmitting SSB to the terminal in a specific cell when the on-demand SSB procedure is not applied. In other words, the base station can reduce energy consumption by performing SSB transmission only when the on-demand SSB procedure is applied / accompanied.

[0258] The on-demand SSB process can be triggered based on at least one of the following actions:

[0259] 1) An operation in which a terminal transmits a request for SSB transmission to a base station through an uplink signal / channel (e.g., PRACH, PUCCH, PUSCH, SRS, etc.).

[0260] 2) An action whereby base station #1 (or TRP #1) requests SSB transmission to base station #2 (or TRP #2) through an interface between base stations (e.g., Xn interface, etc.) or backhaul signaling, etc.

[0261] 3) An action in which the base station signals whether to transmit SSB for the corresponding SCell by transmitting SCell activation / deactivation signaling to the terminal.

[0262] The on-demand SSB operation (on PCell and / or SCell) and related information described below can be applied not only to terminals in connected mode, but also to terminals in inactive (or idle) mode or terminals performing initial connection. In other words, the on-demand SSB operation (on PCell and / or SCell) can be applied not only to terminals in basic wireless communication systems but also to terminals in next-generation communication systems.

[0263] Additionally, the on-demand SSB operation applied to carrier aggregation (CA) that includes the SCell can also be applied to intra-band CA or inter-band CAD. The SSB transmitted on the SCell via the on-demand SSB process can be used at least for time / frequency synchronization, L1 / L3 measurements, and SCell activation procedures.

[0264] On-demand system information (e.g., SIB1) transmission procedure

[0265] In basic wireless communication systems, for initial connection or idle mode terminals to access a cell, the terminal is required to periodically transmit system information (e.g., SIB1) containing system information, random access information, etc. to the terminal. In other words, the base station is required to transmit system information even when there is no data to transmit or receive, which leads to the problem of unnecessary energy consumption.

[0266] Accordingly, the base station can reduce energy consumption of the base station by transmitting SIB1 for a specific cell to the terminal through the on-demand SIB1 process and not transmitting SIB1 for a specific cell to the terminal when the on-demand SIB1 process is not applied.

[0267] As an example of the present disclosure, a terminal may trigger SIB1 transmission of a base station by transmitting an uplink signal / channel (e.g., PRACH, etc.) to the base station, and at least one of the scenarios described below may be applied.

[0268] Scenario 1: As illustrated in (a) of FIG. 19, the UE may recognize that SIB1 is not transmitted in cell #1 by receiving an SSB (and / or other downlink signal channel) from the base station in cell #1. The UE may trigger SIB1 transmission by transmitting a signal requesting SIB1 to the base station based on information provided via the SSB (and / or other downlink signal / channel) and / or predetermined information. In describing the present disclosure, the signal requesting SIB1 may be collectively referred to as a WUS (wake-up signal), but is not limited thereto. The base station receiving the WUS may transmit a specific DL signal / channel (e.g., an ACK signal) to the UE on cell #1 in response to the WUS. Additionally or alternatively, the base station may transmit SIB1 to the UE on cell #1 (without a specific DL signal / channel) in response to the WUS.

[0269] Scenario #2: As illustrated in (b) of FIG. 19, the UE may recognize that SIB1 is not transmitted in cell #2 by receiving an SSB (and / or other downlink signaling channel such as SIB1) from the base station in cell #1. The UE may attempt to camp on cell #2. The UE may trigger SIB1 transmission for cell #2 by transmitting a signal (e.g., WUS) requesting SIB1 to the base station on cell #1 based on information provided through the received SSB (and / or other downlink signaling / channel such as SIB1) and / or predetermined information. The base station receiving the WUS may transmit a specific DL signal / channel to the UE (on cell #1 or cell #2) in response to the WUS. Additionally or alternatively, the base station may transmit SIB1 for cell #2 to the UE on cell #1 or cell #2 (without the specific DL signal / channel) in response to the WUS.

[0270] Scenario #3: As illustrated in (c) of FIG. 19, the UE may recognize that SIB1 is not transmitted in cell #2 by receiving an SSB (and / or other downlink signaling channel such as SIB1) from the base station in cell #1. The UE may attempt to camp on cell #2. The UE may trigger SIB1 transmission for cell #2 by transmitting a signal (e.g., WUS) requesting SIB1 to the base station on cell #2 based on information provided through the received SSB (and / or other downlink signaling / channel such as SIB1) and / or predetermined information. The base station receiving the WUS may transmit a specific DL signal / channel to the UE (on cell #1 or cell #2) in response to the WUS. Additionally or alternatively, the base station may transmit SIB1 for cell #2 to the UE on cell #1 or cell #2 (without the specific DL signal / channel) in response to the WUS.

[0271] Network Energy Saving (NES)

[0272] Energy conservation at base stations is a key consideration in wireless communication systems, as it can contribute to building eco-friendly networks by reducing carbon emissions and reducing operational expenditures (OPEX) for telecommunications companies. In particular, the introduction of next-generation wireless communications requires higher transmission rates, necessitating base stations to be equipped with more antennas and provide services across wider bandwidths and frequency bands.

[0273] Because of this, the energy cost of the base station increases excessively, so the base station needs to apply energy-saving methods.

[0274] In the improved wireless communication system, SSB-less SCell operation for inter-band CA of FR 1 and co-located cells, cell DTX / DRX and terminal DRX alignment operation in RRC_connected mode, and inter-node information exchange of cell DTX / DRX can be performed.

[0275] In addition, spatial and power domain technologies that enable efficient adaptation of spatial elements, efficient adaptation of power offset values ​​between PDSCH and CSI-RS, methods for preventing camping of legacy terminals in cells where NES technology is applied, conditional handover (CHO) methods, inter-node beam activation methods that limit paging in limited areas, and radio resource management (RRM) / RF methods can be applied.

[0276] From the perspective of a base station operating multiple frequency bands, even when the number of terminals served is small or the traffic load is relatively low, the amount of energy consumed by periodically transmitting SSB and / or system information, etc. may be large.

[0277] In the description of the present disclosure, frequency band may be replaced with band, carrier, serving cell, or BWP.

[0278] FIG. 20 illustrates an SSB transmission method of a base station operating multiple frequency bands applicable to the present disclosure.

[0279] Referring to FIG. 20, a base station operating on three frequency bands may periodically transmit (legacy) SSB only on some frequency bands (e.g., F1 in FIG. 20). Conversely, the base station may transmit simplified (or modified) SSB (S-SSB) on the remaining frequency bands (e.g., F2 in FIG. 20) or may not transmit SSB on other frequency bands (e.g., F3 in FIG. 20). Through this, the base station may achieve energy conservation.

[0280] After the terminal moves from F1 to F2 / F3 and performs the on-demand SIB1 procedure, the terminal can receive SSB and / or SIB1 for the corresponding F2 or F3 frequency band from the base station. Then, the terminal can perform the RACH procedure, etc., enter connected mode, and transmit DL and / or UL data via F2 or F3.

[0281] Additionally, in describing the present disclosure, a frequency band in which S-SSB can be transmitted (such as F2) and a frequency band in which SSB cannot be transmitted (such as F3), or a frequency band in which SIB1 can be transmitted through an on-demand SIB1 process, may be collectively referred to as the F2 frequency band. However, this is merely an example, and the above-described procedure(s) may be applied to both F2 and F3.

[0282] In the present disclosure, as shown in F1 of FIG. 20, a frequency band in which information about another frequency band is provided as SSB and / or SIB1 is transmitted is named an anchor cell. Here, the information about the other frequency band may include i) information about whether the current SIB1 is transmitted periodically, ii) if SIB1 is transmitted periodically, information about the transmission time pattern of SIB1 in the other frequency band, and / or iii) if SIB1 is not transmitted periodically, setting information about terminal WUS resources for an on-demand SIB1 procedure.

[0283] In addition, other frequency bands provided via SSB and / or SIB1 on the anchor cell are referred to as non-anchor cells. In addition, in describing the present disclosure, the terminal may assume that there is an association or QCL relationship between the anchor cell and the non-anchor cell.

[0284] Hereinafter, when a terminal in an inactive / idle state in a cell operating on-demand SIB1 requests SIB1 transmission to a base station through a wake-up signal (WUS) (or (P)RACH), the WUS transmission conditions, WUS transmission and transmission / reception procedures, and WUS transmission failure handling and retransmission procedures will be described.

[0285] FIG. 21 is a flowchart illustrating the operation of a terminal according to one embodiment of the present disclosure. The terminal described with reference to FIGS. 21 and 22 may be in a radio resource control (RRC) inactive or RRC idle state, but is not limited thereto.

[0286] The terminal may transmit a first random access channel (RACH) to the base station for a request for an on-demand SIB (e.g., SIB_n) (n is a natural number greater than or equal to 1) of the first cell (S2110).

[0287] Specifically, the terminal can camp on the first cell and receive system information from the base station through the first cell. Here, the system information can include configuration information related to RACH, etc. The terminal can transmit the first RACH (or MSG. 1) to the base station based on the configuration information related to RACH included in the system information (e.g., resource information for requesting an on-demand SIB of the first cell, etc.). The first RACH can include an RRC connection request message or an RRC connection resume request message, etc.

[0288] Additionally or alternatively, the first RACH may include information for performing initial access to the first cell. That is, the terminal may transmit the first RACH to the base station for an on-demand SIB request of the first cell and / or for initial access to the first cell.

[0289] Accordingly, the terminal can receive the on-demand SIB of the first cell from the base station through the first cell. In addition, the terminal can perform an initial access operation in the first cell.

[0290] For example, the on-demand SIB of the first cell may include at least one of: i) information related to at least one cell or at least one frequency band, ii) at least one cell-specific common cell reselection priority, or iii) at least one frequency band-specific common cell quality offset.

[0291] Here, the first cell may be an anchor cell, and at least one cell or a cell associated with at least one frequency band may be a NES cell, but is not limited thereto.

[0292] The terminal can receive a first response message from the base station that includes redirection information for at least one cell or at least one frequency band (S2120).

[0293] Here, the first response message may include message 2, message 4, or message B. For example, the first response message may be transmitted to the terminal via a radio resource control (RRC) message or a medium access control (MEC) control element (CE).

[0294] Here, the redirection information may include information for switching from the first cell to at least one cell or to a cell associated with at least one frequency band. For example, the redirection information may include at least one of a cell quality offset for each of at least one cell, a cell reselection priority for each of at least one frequency band, or a frequency selection probability for each of at least one frequency band.

[0295] For example, based on a random value selected by the terminal and a frequency selection probability for at least one frequency band, the terminal may select a first frequency band among at least one frequency band.

[0296] For example, a frequency selection probability may be set for at least one frequency band, and the terminal may select a random value between 0 and 1. Based on whether the random value selected by the terminal corresponds to the frequency selection probability associated with the first frequency band, the terminal may select the first frequency band.

[0297] The terminal may transmit a second RACH to the base station for an on-demand SIB request of a second cell or a third cell among at least one cell related to a first frequency band among at least one frequency band based on the redirection information (S2130).

[0298] Specifically, the terminal may perform a cell reselection operation for at least one cell, a second cell, or a third cell associated with the first frequency band, based on redirection information. Furthermore, the terminal may transmit a second RACH to the base station to request an on-demand SIB of the second cell or the third cell. The terminal may receive the on-demand SIB of the second cell or the third cell from the base station based on the second RACH.

[0299] Additionally or alternatively, the second RACH may include information for initial access to the second cell or the third cell. The terminal may perform an access operation to the second cell or the third cell based on the second RACH.

[0300] Here, Cell 1 and Cell 2 (or / and Cell 3) may be associated with or belong to the same radio access technology (RAT), but are not limited thereto. Each of Cell 1 and Cell 2 (or / and Cell 3) may be associated with or belong to a different RAT.

[0301] The method described in the example of FIG. 21 may be performed by the first device (100) of FIG. 1. For example, one or more processors (102) of the first device (100) of FIG. 1 may transmit a first RACH for requesting an on-demand SIB of a first cell to a base station through one or more transceivers (106). The one or more processors (102) may receive, from the base station through one or more transceivers (106), a first response message including redirection information for at least one cell or at least one frequency band. The one or more processors (102) may transmit, to the base station through one or more transceivers (106), a second RACH for requesting an on-demand SIB of a second cell associated with the first frequency band among the at least one frequency band or a third cell among the at least one cell based on the redirection information.

[0302] Furthermore, one or more memories (104) of the first device (100) may store commands for performing the method described in the example of FIG. 21 or the examples described below when executed by one or more processors (102).

[0303] FIG. 22 is a flowchart for explaining the operation of a base station according to one embodiment of the present disclosure.

[0304] The base station may receive a first RACH from a terminal for requesting an on-demand SIB of a first cell (S2210). Specifically, the base station may receive a first RACH from a terminal camped on the first cell, and the first RACH may include information for requesting and / or initial access to an on-demand SIB transmission of the first cell. The base station may transmit the on-demand SIB to the terminal via the first cell.

[0305] The base station may transmit a first response message containing redirection information for at least one cell or at least one frequency band to the terminal (S2220). The configuration of the redirection information has been described with reference to FIG. 21, so a redundant description will be omitted.

[0306] The base station may transmit a second RACH for an on-demand SIB request of a second cell or a third cell among at least one cell related to a first frequency band among at least one frequency band based on the redirection information to the base station (S2230).

[0307] The base station can transmit an on-demand SIB of a second cell or a third cell to the terminal based on the second RACH.

[0308] The method described in the example of FIG. 22 may be performed by the second device (200) of FIG. 1. For example, one or more processors (202) of the second device (200) of FIG. 22 may receive a first RACH for a request for an on-demand SIB of a first cell from a terminal through one or more transceivers (206). The one or more processors (202) may transmit a first response message including redirection information for at least one cell or at least one frequency band to the terminal through the one or more transceivers (206). The one or more processors (202) may receive, from a base station through the one or more transceivers (206), a second RACH for a request for an on-demand SIB of a second cell related to a first frequency band among the at least one frequency band or a third cell among the at least one cell based on the redirection information.

[0309] Furthermore, one or more memories (204) of the second device (200) may store commands for performing the method described in the example of FIG. 22 or the examples described below when executed by one or more processors (202).

[0310] Below, the procedure for requesting / transmitting on-demand SIB1 and information related to the priority of a cell requesting on-demand SIB1 when the number of cells supporting on-demand SIB1 is 2 or more are specifically described.

[0311] Example 1

[0312] Example 1 relates to an on-demand SIB1 request and transmission / reception procedure related to an anchor cell.

[0313] In describing the present disclosure, CORESET0 and Search Space 0 may collectively refer to the CORESET and search space for the PDCCH and DCI that schedule the PDSCH carrying SIB1 (hereinafter, "SIB1 PDSCH"). CORESET 0 and Search Space 0 for the anchor cell may be included in the common CORESET, common search space, and configuration information related to required PDCCH parameters (e.g., "pdcch-ConfigSIB1") of the MIB of the anchor cell and broadcasted to terminals.

[0314] In describing the present disclosure, the SIB1 PDSCH of an anchor cell is expressed as an anchor SIB1 PDSCH or aSIB1 PDSCH, and the SIB1 PDSCH of a non-anchor cell is expressed as a non-anchor SIB1 PDSCH or nSIB1 PDSCH.

[0315] As an example of the present disclosure, the MIB of an anchor cell or a specific DCI (e.g., a DCI scheduling an anchor cell SIB1 or a separate anchor DCI) may configure CORESET0 and search space 0 of DCI scheduling an nSIB1 PDSCH for one or more non-anchor cell(s) transmitted from the anchor cell or a non-anchor cell. In this case, the MIB of the anchor cell or the specific DCI may include configuration information for the DCI scheduling the nSIB1 PDSCH (e.g., configuration information related to a common CORESET, a common search space, and required PDCCH parameters (“pdcch-ConfigSIB1”)).

[0316] As an example of the present disclosure, the nSIB1 PDSCH may include one or more SIB1(s) for one or more non-anchor cells, and the one or more SIB1(s) may be included in one SI message. Here, the RRC layer in the gNB-CU multiplexes multiple nSIB1s obtained from one or more gNBs into one RRC message and transmits it to the gNB-DU of the anchor cell, and the gNB-DU of the anchor cell transmits it to the UE of the anchor cell.

[0317] Additionally or alternatively, assume that the gNB-CU transmits multiple nSIB1s acquired from one or more gNBs to the gNB-DU of the anchor cell. In this case, the gNB-DU of the anchor cell can configure different nSIB1 messages into different MAC SDUs, multiplex these MAC SDUs into a single MAC PDU, and transmit them to the UE of the anchor cell.

[0318] Information about non-anchor cells mapped to one or more nSIB1s included in the SI message may be indicated via the SIB1 of the anchor cell or the DCI scheduling the aSIB1 PDSCH or the DCI scheduling the nSIB1 PDSCH or a separate DCI.

[0319] For example, when nSIB1 PDSCH schedules SIB1s for each of non-anchor cells Cell ID #a, Cell ID #b, Cell ID #c and Cell ID #d, cell access information for Cell ID #2 (e.g., global cell ID and / or physical cell ID and / or frequency carrier information and / or Public Land Mobile Network (PLMN) ID and / or tracking area ID, etc.) may be transmitted to UEs via an anchor cell message (e.g., anchor cell SIB1, anchor cell SIB, UE-only message, anchor MAC CE, or DCI of the anchor cell).

[0320] Here, the anchor cell message may indicate / include the number of cells (e.g., 4) and the respective cell indexes on the non-anchor cell list (e.g., cell ID #a, cell ID #b, cell ID #c, cell ID #d). For example, cells a, b, c, and d may be set to cell indices of 0, 1, 2, and 3, respectively, according to the order of the non-anchor cell cell list included in the anchor cell SIB1.

[0321] Additionally, non-anchor cell SIB1s may be configured to be multiplexed into one SI message. For example, based on information in the anchor cell message, SIB1a of cell ID #a and SIB1c of cell ID #c may be multiplexed into the first SI message and transmitted, and SIB1b of cell ID #b and SIB1d of cell ID #d may be configured to be transmitted as separate SI messages without being multiplexed into the second SI message and the third SI message, respectively.

[0322] Additionally, when SIB1a and SIB1c are multiplexed into one SI message, the DCI scheduling the SI message may indicate cell indices 0 and 2 for cell ID #a and cell ID #c. At this time, the DCI may include a specific bitmap as many as the number of listed non-anchor cells, and a non-anchor cell may be indicated in the order of the non-anchor cell list at each bit position.

[0323] For example, if four cells are listed, the first bit position to the fourth bit position of a specific bitmap of the corresponding DCI may be mapped to SIB1a, SIB1b, SIB1c, and SIB1d, respectively. If the second bit value in the specific bitmap of the corresponding DCI is 0, this may indicate / inform the terminal(s) that the on-demand SIB1 for cell ID #b is not currently being transmitted and / or that an on-demand SIB1 request is required. If the second bit value in the specific bitmap of the corresponding DCI is 1, this may indicate / inform the terminal(s) that the on-demand SIB1 for cell ID #b is currently being transmitted and / or that an on-demand SIB1 request is not required.

[0324] If a terminal receiving the above DCI wants to receive on-demand SIB1 for cell ID #b, the terminal must check the second bit in a specific bitmap of the DCI. For example, if the second bit value is 0, the terminal may trigger a procedure for requesting on-demand SIB1 for cell ID #b. As another example, if the second bit value is 1, the terminal may acquire scheduling information of on-demand SIB1 for cell ID #b without requesting on-demand SIB1 for cell ID #b and attempt to receive on-demand SIB1 for cell ID #b based on the scheduling information.

[0325] At this time, if the DCI schedules only SIB1a and SIB1c, it may indicate whether to transmit SIB1 on-demand for SIB1b and SIB1d. The DCI including the specific bitmap may be a DCI scheduling aSIB1 PDSCH, a DCI scheduling nSIB1 PDSCH, or a separate DCI.

[0326] In another way, if the second bit value in a specific bitmap of the corresponding DCI is 0, the PDSCH scheduled by the corresponding DCI may not include / multiplex SIB1b. If the second bit value in a specific bitmap of the corresponding DCI is 1, the PDSCH scheduled by the corresponding DCI may include / multiplex SIB1b.

[0327] Therefore, when SIB1a of cell ID #a and SIB1c of cell ID #c are multiplexed into the first SI message and transmitted as one PDSCH, a specific bitmap value of the DCI scheduling these PDSCHs may be set to “1010”.

[0328] For example, if the SI message of the PDSCH only transmits SIB1b, a specific bitmap value of the DCI scheduling the PDSCH may be set to "0100." Accordingly, the terminal may determine whether to receive the PDSCH transmitting the SI message based on the value of the specific bitmap.

[0329] For example, if a specific bitmap value of the DCI scheduling the PDSCH is set to "1010," a terminal requesting on-demand transmission of SIB1c can receive the corresponding PDSCH and obtain an SI message. As another example, if a specific bitmap value is set to "0100," the terminal may not receive or process the corresponding PDSCH.

[0330] As another example, the RNTI of the DCI scheduling the non-anchor SIB1 or SI messages for the SIB1 may be set to a specific RNTI value. For example, depending on the configuration of the anchor cell message, the RNTI of the DCI scheduling the first SI message may be set to SI-RNTI #1, the RNTI of the DCI scheduling the second SI message may be set to SI-RNTI #2, and the RNTI of the DCI scheduling the third SI message may be set to SI-RNTI #3.

[0331] As another example, the RNTIs of the DCIs scheduling the non-anchor SIB1 or SI messages for the SIB1 may all be set to SI-RNTI#1. At this time, the DCIs scheduling the anchor cell SIB1 may be scrambled by SI-RNTI#0 or SI-RNTI#1. That is, depending on the configuration of the anchor cell message, all SIB1s may be scheduled with DCIs having the same SI-RNTI value, or only the non-anchor cell SIBs may be scheduled with DCIs having the same SI-RNTI value, or each may be scheduled with DCIs having different SI-RNTI values.

[0332] For example, when SIB1a and SIB1c are multiplexed into one SI message, the MAC header of the MAC PDU containing the SI message may indicate / include cell indices 0 and 2 for cell ID #a and cell ID #c, or may include logical channel IDs (LCIDs) #0 and LCID #2 mapped to cell indices 0 and 2.

[0333] As another example, when multiple SIB1s are multiplexed into one SI message, the MAC header of the MAC PDU containing the SI message for the non-anchor SIB1 may indicate a specific LCID value. As another example, the MAC PDU may not include a MAC header. Let us assume that the MAC PDU includes a MAC header. In this case, based on the value of the MAC header, if the MAC PDU contains the requested SIB1 or SI message, the terminal requesting the on-demand SIB1 may decide to process the SIB1 or SI message and send it to the upper layer.

[0334] For example, when SIB1a and SIB1c are multiplexed into one SI message, the RRC message including the SI message may indicate / include cell indices 0 and 2 for cell ID #a and cell ID #c, or may include cell ID #a and cell ID #c. As another example, when multiple SIB1s are multiplexed into one SI message, the RRC message including the SI message for the non-anchor SIB1 may indicate a specific code value indicating whether to multiplex.

[0335] For example, the nSIB1 PDSCH may or may not additionally schedule the anchor cell SIB1. If the nSIB1 PDSCH additionally schedules the anchor cell SIB1, a bit indicating the anchor cell may be added to the front or back of the specific bitmap. The additional bit of the corresponding DCI may indicate whether the on-demand SIB1 of the anchor cell is currently being transmitted, or may indicate that the on-demand SIB1 of the anchor cell is also additionally scheduled.

[0336] For example, if the on-demand SIB1 of the anchor cell is additionally scheduled by the DCI, the aSIB1 of the anchor cell may be multiplexed with the nSIB1s and transmitted as a single SI message, or may be scheduled to be transmitted as a separate SIB1 without being multiplexed as a single SI message. If a separate SIB1 is transmitted, the aSIB1 and nSIB1s may be transmitted on separate PDSCHs or may be transmitted on the same PDSCH. For example, information may be transmitted to the terminal regarding whether the on-demand SIB1 for the non-anchor cell listed in the anchor cell message is currently being transmitted, is being scheduled, or whether an on-demand SIB1 request is required.

[0337] Example 2

[0338] Example 2 relates to an access control method to which on-demand SIB1 is applied.

[0339] The terminal may camp on an anchor cell (e.g., cell A) according to the cell selection / reselection process, and may receive an anchor cell message (e.g., SIB1 (SIB1A) of cell A) from cell A. At this time, the anchor cell message may include / indicate information related to listed non-anchor cells (e.g., NES cell ID #1, cell ID #2, cell ID #3, cell ID #4, etc.) (e.g., the number of listed non-anchor cells (e.g., 4) and / or each cell index, etc.).

[0340] For example, the non-anchor cell (e.g., NES cell)(s) included in the Cell A message information (e.g., SIB1A) transmitted by Cell A (or transmitted through Cell A) may be, but is not limited to, cell(s) belonging to the same PLMN as Cell A or the same equivalent PLMN, cell(s) belonging to the same tracking area, or cell(s) belonging to the same gNB.

[0341] Cell A can periodically broadcast MIB and SIB1 for Cell A. That is, MIB and SIB1 for Cell A can be periodically broadcast (by the base station) through Cell A. At this time, MIB or SIB1 can include unified access control (UAC) information for accessing Cell A.

[0342] In one example of the present disclosure, UAC information (or UAC-barring information) may include UAC barring common information (e.g., "uac-BarringFoRCommon"), UAC PLMN list-specific barring information (e.g., "uac-BarringPerPLMN-List"), UAC barring information set list (e.g., "uac-BarringInfoSetList"), UAC barring information set index (e.g., "UAC-BarringInfoSetIndex"), information indicating a probability that a connection attempt is allowed during a connection barring check (e.g., "uac-BarringFactor"), an average time (in seconds) before a new connection attempt is made after a connection attempt is blocked in a connection barring check for the same connection category (e.g., "uac-BarringTime"), information indicating whether an access attempt for each connection ID is allowed (e.g., "uac-BarringForAccessIdentity"), list information of connection control parameter sets (e.g., "uac-BarringInfoSetList"), or connection This may include the possibility of using a blocking factor for identity 3 (e.g., "uac-BarringFactorForAI3").

[0343] For example, the probability that a connection attempt is allowed during a connection blocking check may be one of 0%, 5%, 10%, 15%, 20%, 25%, 30%, 40%, 50%, 60%, 70%, 75%, 80%, 85%, 90%, 95%. The average time (in seconds) between a connection attempt being blocked and a new connection attempt being made during a connection blocking check for the same connection category may be one of 4s, 8s, 16s, 32s, 64s, 128s, 256s, 512s.

[0344] When a terminal that has received UAC information for cell A via SIB1 triggers initial access (IA), the terminal can perform the AC procedure for IA described below (e.g., the operation according to embodiment 2-1). When passing AC (e.g., passing / satisfying a barring check based on AC information), the terminal can trigger a RACH procedure to transmit an RRC setup request message to the base station via MSG3.

[0345] Example 2-1

[0346] Example 2-1 relates to the AC process of RRC connection establishment performed by a terminal.

[0347] A terminal may request RRC connection establishment from a higher layer while in RRC_IDLE state or while acquiring essential system information, or initiate the procedures described below for sidelink communication (hereinafter, RRC connection establishment procedures). Before initiating the procedures described below, the terminal may verify that it possesses valid and up-to-date essential system information.

[0348] Once the above procedure is initiated, the terminal can perform the following actions:

[0349] 1> When the upper layer requests RRC connection setup, if it provides a connection category and one or more access IDs:

[0350] 2> Perform the integrated access control procedure described below using the access category and access ID provided by the upper layer;

[0351] 3> The process may terminate if the connection attempt is blocked;

[0352] 1> Start timer T300;

[0353] 1> Start sending "RRCSetupRequest" message (to trigger RACH for initial access).

[0354] The integrated access control procedure is described below.

[0355] When the procedure starts, the terminal can perform the following actions:

[0356] 1> If Timer T390 is running for the connection category:

[0357] 2> The connection attempt may be considered blocked;

[0358] 1> If timer T302 is running and the connection category is neither '2' nor '0':

[0359] 2> The access attempt may be considered blocked;

[0360] 1> If not:

[0361] 2> If the connection category is '0':

[0362] 3> The connection attempt may be considered allowed;

[0363] 2> If not:

[0364] 3> If SIB1 contains access control parameters including "uac-BarringPerPLMN-List" (i.e., information providing access control parameters per access category set per PLMN / SNPN) for the selected PLMN or Standalone Non-Public Network (SNPN):

[0365] 4> If the procedure for the selected PLMN used information from the "npn-IdentityInfoList" (i.e., NPN-Identity element set information) and there is an entry in "UAC-BarringPerPLMN" with a "plmn-IdentityIndex" corresponding to the information used in that list:

[0366] 5> You can select the "UAC-BarringPerPLMN" entry with the "plmn-IdentityIndex" corresponding to the information used in "npn-IdentityInfoList";

[0367] 4> If not:

[0368] 5> You can select the "UAC-BarringPerPLMN" entry with the "plmn-IdentityIndex" corresponding to the selected PLMN and "PLMN-IdentityInfo" (if present) or the "npn-IdentityInfoList" with the selected SNPN;

[0369] 3> If the "UAC-BarringPerPLMN" item is selected:

[0370] 4> For the remainder of the procedure, the selected "UAC-BarringPerPLMN" entry (i.e. whether it has a connection-barring parameter) can be used regardless of the "uac-BarringForCommon" included in SIB1;

[0371] 3> If SIB1 contains "uac-BarringForCommon":

[0372] 4> For the rest of the procedure, you can use "uac-BarringForCommon" included in SIB1 (i.e. whether that parameter is present or not);

[0373] 3> Otherwise:

[0374] 4> The access attempt may be considered permitted;

[0375] 3> If "uac-BarringForCommon" is applicable or "uac-ACBarringListType" indicates the use of "uac-ExplicitACBarringList":

[0376] 4> If the "UAC-BarringPerCatList" contains a "UAC-BarringPerCat" entry corresponding to the access category:

[0377] 5> You can select the "UAC-BarringPerCat" item;

[0378] 5> If "uac-BarringInfoSetList" contains a "UAC-BarringInfoSet" entry corresponding to the "uac-barringInfoSetIndex" selected in "UAC-BarringPerCat":

[0379] 6> You can select the "UAC-BarringInfoSet" item.

[0380] 6> You can perform access blocking check for connection categories by using the selected "UAC-BarringInfoSet" as the "UAC blocking parameters".

[0381] 5> Otherwise:

[0382] 6> The connection attempt may be considered allowed.

[0383] 4> If not:

[0384] 5> The connection attempt may be considered allowed;

[0385] 3> If "uac-ACBarringListType" indicates that "uac-ImplicitACBarringList" is used:

[0386] 4> You can select "uac-BarringInfoSetIndex" corresponding to the connection category of "uac-ImplicitACBarringList";

[0387] 4> If "uac-BarringInfoSetList" contains a "UAC-BarringInfoSet" entry corresponding to the selected "uac-BarringInfoSetIndex":

[0388] 5> You can select the "UAC-BarringInfoSet" item;

[0389] 5> You can perform access blocking check for the access category by using the selected "UAC-BarringInfoSet" as the "UAC blocking parameter".

[0390] 4> If not:

[0391] 5> The connection attempt may be considered allowed.

[0392] 3> If not:

[0393] 4> The connection attempt may be considered allowed;

[0394] 1> If a connection blocking check is requested from a higher layer:

[0395] 2> If your connection attempt is considered blocked:

[0396] 3> If timer T302 is running:

[0397] 4> If Timer T390 is running for connection category '2':

[0398] 5> The upper layer is notified that access blocking is applied to all access categories except category '0', and the procedure can be terminated.

[0399] 4> If not;

[0400] 5> The upper layer is notified that access blocking is applied to all access categories except categories '0' and '2', and the procedure can be terminated.

[0401] 3> If not:

[0402] 4> Notifies the upper layer that an access attempt for that access category is blocked, and the procedure can be terminated.

[0403] 2> If not:

[0404] 3> Notify the upper layer that the access attempt for that access category is allowed, and the process can be terminated.

[0405] 1> If not:

[0406] 2> The procedure may be terminated.

[0407] Example 3

[0408] Example 3 relates to a method for requesting SIB1 of cell 1 when a terminal camps on cell A and receives AC information of cell 1 through cell A, and passes through AC of cell 1.

[0409] Step 1: The base station can broadcast AC information per cell or AC information per cell group through SIB1A broadcasted by cell A, and the terminal can receive AC information broadcasted through SIB1A.

[0410] The terminal can obtain AC information of cell 1 through SIB1A. For example, the AC information of cell 1 may include AC information for IA and AC information for on-demand SIB1. The AC information for IA and AC information for on-demand SIB1 may be distinguished within the AC information of cell 1, but is not limited thereto, and may be integrated without distinction.

[0411] Additionally, cell A can broadcast common AC information applicable to multiple NES cells. For example, if cell 1, cell 2, cell 3, and cell 4 are all NES cells, cell A can broadcast the IDs of each of cell 1, cell 2, cell 3, and cell 4. Additionally or alternatively, cell A can broadcast AC information applicable to at least one of cell 1, cell 2, cell 3, and cell 4.

[0412] For example, SIB1A may broadcast AC information according to one of the examples described below (e.g., Example A, Example B, Example C). At this time, the first AC information, the second AC information, or the integrated AC information corresponds to the AC information of cell A (at this time, the terminal performs the AC process based on the AC information of cell A), or is AC information separate from the AC information of cell A.

[0413] Example A: Broadcast first AC information common to cells 1 and 2 and second AC information common to cells 3 and 4.

[0414] Example B: Broadcast first AC information common to cells 1, 2, and 3 and second AC information applicable only to cell A.

[0415] Example C: Consolidated AC information common to cells 1, 2, 3, and 4

[0416] At this time, AC information may be configured to be divided into AC information for IA and AC information for on-demand SIB1, but is not limited thereto. AC information for IA and AC information for on-demand SIB1 may be configured as integrated AC information without distinction of purpose. In addition, the cell group applied to AC information for IA and the cell group applied to AC information for on-demand SIB1 may be configured to be the same or different, and the AC information for IA and AC information for on-demand SIB1 may be broadcast.

[0417] For example, SIB1A can be configured and broadcast such that information according to Example A is set as AC information for IA, and information according to Example B or Example C is set as AC information for on-demand SIB1.

[0418] Step 2: The terminal can perform the AC process based on the received AC information.

[0419] As an example of the present disclosure, when a condition related to AC is satisfied (or, AC is allowed / passed), the terminal may perform at least one of the following operations:

[0420] - The terminal may initiate an uplink transmission (e.g., RACH) to request on-demand SSB transmission of cell 1. Accordingly, the base station may broadcast the SSB of cell 1;

[0421] - The terminal can start measuring SSB of cell 1 according to SSB broadcast information of cell A.

[0422] As an example of the present disclosure, regardless of whether a condition associated with AC is satisfied (or regardless of whether AC is accepted / passed), the terminal may perform at least one of the following operations:

[0423] - When Cell A provides SSB broadcast information or on-demand SSB information to Cell 1;

[0424] -- The terminal may initiate an uplink transmission (e.g., RACH) to request on-demand SSB transmission of cell 1. Accordingly, the base station may broadcast the SSB of cell 1;

[0425] -- The terminal can start measuring the SSB of cell 1 according to the SSB broadcast information of cell A;

[0426] - If SIB1A indicates that measurements on a specific frequency are allowed (by Cell A) even though Cell A does not provide information on Cell 1, the terminal may measure that frequency and perform at least one of the following actions:

[0427] -- The terminal can initiate RACH to request SIB1 of cell 1 only if the measured frequency is above the threshold (set by cell A);

[0428] -- A terminal may initiate a RACH to request SIB1 of cell 1 only if it is indicated that on-demand SIB1 request for a specific frequency is allowed.

[0429] Example 4

[0430] In one embodiment of the present disclosure, when a SIB1 of cell 1 is received (via cell A or cell 1) while transmitting / initiating a RACH for a SIB1 request (and / or IA) of cell 1, even if AC information is included in the received SIB1 of cell 1, the terminal may continue the on-going RACH for the SIB1 request of cell 1. Specifically, the terminal may perform operations according to the steps described below.

[0431] Step 1: The terminal camps on Cell A and can receive configuration information related to RACH for SIB1 request of Cell 1 from the base station through SIB1A broadcasted by Cell A. The terminal can receive PBCH of Cell 1 from the base station according to Example 3.

[0432] For example, if cell 1 is blocked according to the instruction of PBCH, the terminal may consider cell 1 to be blocked for the time indicated by cell A (or for a fixed specific time period, such as 300 seconds) and may not perform the operations according to the steps described below during that time period. As another example, if cell 1 is not blocked according to the instruction of PBCH, the terminal may perform the operations according to the steps described below.

[0433] Step 2: The terminal may initiate a RACH to request SIB1 of Cell 1 based on the configuration information associated with the RACH. At this time, the RACH may be a RACH for performing IA while requesting on-demand SIB1 for Cell 1. The RACH may be transmitted to the base station based on the uplink resources of Cell A or Cell 1.

[0434] Step 3: (Other terminals may already request SIB1 of Cell 1) The terminal may receive SIB1 of Cell 1 that it attempted to request before / during / immediately after transmitting / receiving MSG 1 / 2 / 3 of the started RACH or MSGA / B. If the terminal acquires AC information through SIB1 of Cell 1 during the process of performing RACH, the terminal may continue performing the RACH. Accordingly, the terminal may transmit an RRC setup request message to the base station through MSG3.

[0435] Step 4: The base station may perform access control procedures for the terminal based on the reception of MSG3. The base station may determine whether to accept or reject the setup request from the terminal.

[0436] As an example of the present disclosure, when the base station accepts the setup request of the corresponding terminal, the base station may transmit RRC setup for cell 1 (or RRC setup related information or / and message (e.g., message indicating acceptance of the setup request of the corresponding terminal)) to the base station via RACH MSG4 in response to MSG3. The terminal may transmit an RRC setup complete message to the base station via RACH MSG5. The terminal may successfully complete the RRC connection establishment process and switch to RRC_connected mode. Accordingly, the terminal may set cell 1 as the primary cell.

[0437] For example, the base station can include SIB1 for cell 1 in the RRC setup and transmit it to the terminal.

[0438] As another example, a terminal can request SIB1 of cell 1 from the base station via MSG1, MSG3, or MSG5 of the RACH. Accordingly, after the RACH is terminated, the base station can transmit the requested SIB1 to the terminal through a separate terminal-specific signaling. At this time, in addition to SIB1 of cell 1, the base station can also transmit SIB1 of neighboring cells (e.g., cell 2, cell 3, etc.) to the terminal through a separate terminal-specific signaling (based on the terminal's request or even without the terminal's request).

[0439] As another example, after the RACH is terminated and the RRC_connected transition is completed, the UE may transmit an uplink message requesting SIB1 of cell 1 (and / or SIB1 of neighboring cells 2, 3, etc.) to the base station. The base station may transmit SIB1 of cell 1 (and / or SIB1 of neighboring cells 2, 3, etc.) to the UE through separate UE-only signaling according to the UE request. At this time, the uplink message may be one of uplink control information, MAC CE, or an RRC message.

[0440] As another example of the present disclosure, if the base station rejects the setup request from the terminal, the base station may transmit an RRC rejection message to the terminal instead of an RRC setup message in response to MSG3. If the terminal receives the RRC rejection message, the terminal may fail to transition to RRC_connected mode by unsuccessfully terminating the RRC connection establishment process.

[0441] As another example, even if the base station rejects the setup request from the terminal, it can transmit an RRC setup for a third cell (e.g., cell 2) other than cell 1 to the terminal via RACH MSG4 in response to MSG3. Accordingly, the terminal can successfully complete the RRC connection establishment process and transition to RRC_connected mode by transmitting an RRC setup complete message to the base station via RACH MSG5. Accordingly, the terminal can configure cell 2 as the primary cell.

[0442] At this time, the base station can include SIB1 for cell 2 in the RRC setup and transmit it to the terminal.

[0443] As another example, a terminal can request SIB1 of cell 2 from the base station via MSG1, MSG3, or MSG5 of the RACH. Accordingly, after the RACH is terminated, the base station can transmit the requested SIB1 to the terminal via separate terminal-specific signaling. At this time, in addition to SIB1 of cell 2, the base station can also transmit SIB1 of neighboring cells (e.g., cell 1, cell 3, etc.) to the terminal via separate terminal-specific signaling (based on the terminal's request or even without the terminal's request).

[0444] As another example, after the RRC_connected transition after the RACH is terminated, the UE can transmit an uplink message requesting SIB1 of Cell 2 (and / or SIB1 of neighboring Cell 1, Cell 3, etc.) to the base station. The base station can transmit SIB1 of Cell 2 (and / or SIB1 of neighboring Cell 1, Cell 3, etc.) to the UE through separate UE-only signaling according to the UE request. At this time, the uplink message can be one of uplink control information, MAC CE, or an RRC message.

[0445] Step 5: If the base station transmits an RRC rejection (or rejection message) to the terminal for the IA attempt to Cell 1 in response to the RRC request in the above step, the base station may include on-demand SIB1 information and redirection information in the RRC rejection. That is, the terminal may receive an RRC rejection including on-demand SIB1 information and redirection information from the base station.

[0446] As an example of the present disclosure, the on-demand SIB information in the RRC reject message may include at least one of the following information:

[0447] - On-demand SIB1 of cell 1 requested by the base station through the above RACH or / and RACH configuration information for requesting SIB1 from cell 1;

[0448] - On-demand SIB1 for each of one or more NES cells other than Cell A and Cell 1, regardless of whether a request is made via the RACH of the base station, or / and RACH configuration information for requesting SIB1 from Cell 1.

[0449] As another example of the present disclosure, the redirection information in the RRC rejection message may include at least one of the following information:

[0450] - Redirection information for at least one of cell 2 on the same frequency as cell 1, cell 3 on a third frequency other than the same frequency as cell 1, and cell 4 on a fourth frequency;

[0451] - Redirection information includes cell ID and frequency information (e.g., ARFCN) for each of cell 2, cell 3, and / or cell 4.

[0452] The permanent cells may be cells belonging to the same PLMN or cells belonging to the same tracking area or RAN area.

[0453] Additionally or alternatively, the redirection information may be set / defined to different values ​​depending on the terminal type, terminal capability information, or terminal service. For example, when the terminal type, terminal capability, or terminal service is indicated through MSG1, MSG3, or MSGA, the base station may set redirection information according to the terminal type (e.g., reduced capability (RedCap) terminal or normal terminal, etc.), terminal capability, or terminal service, and transmit the set redirection information to the terminal.

[0454] Step 6: If on-demand SIB1 information and / or redirection information is received from an RRC rejection, the UE may request on-demand SIB1 or perform redirection to at least one of Cell 1, Cell 2, Cell 3, or Cell 4.

[0455] For example, assume that Cell 1 and Cell 2 are on the highest priority frequency (e.g., Cell 2 is the highest ranked cell on that frequency). If SIB1 for Cell 2 is included in the RRC rejection, the UE may perform cell reselection operation and / or IA (e.g., IA to Cell 2) to Cell 2 based on that SIB1.

[0456] If SIB1 for cell 2 is not included in the RRC rejection and a RACH setting for requesting on-demand SIB1 for cell 2 is included in the RRC rejection, the UE can request on-demand SIB1 of cell 2 by performing RACH to cell 2 based on the RACH setting.

[0457] For example, assume that the RACH configuration for requesting SIB1 for Cell 2 and on-demand SIB1 for Cell 2 is not included in the RRC rejection. At this time, if the RACH configuration of Cell 2 exists in SIBA, the UE can request on-demand SIB1 of Cell 2 or perform IA (e.g., IA to Cell 2). As another example, the UE can perform RACH after cell reselection to another cell on the same frequency or a cell on a different frequency other than Cell 2. As another example, the UE can remain in a camp-on state on Cell A without cell reselection.

[0458] As another example of the present disclosure, assume that there is frequency information with a higher priority than the frequencies of cell 1 and cell 2 in the redirection information.

[0459] At this time, if a cell is present on the highest priority frequency based on redirection information, the terminal may select that cell. If no cell is detected on the highest priority frequency, the terminal may select a cell on a frequency with the next higher priority. Additionally or alternatively, the terminal may select Cell 3, the highest-ranking cell on the selected frequency.

[0460] For example, if SIB1 for cell 3 is included in the RRC rejection, the UE can perform cell reselection to cell 3 based on the SIB1 and perform IA (e.g., IA to cell 3). If SIB1 for cell 3 is not included in the RRC rejection, but a RACH setting for requesting on-demand SIB1 for cell 3 is included in the RRC rejection, the UE can request on-demand SIB1 of cell 3 from the base station by performing RACH to cell 3 based on the RACH setting.

[0461] For example, assume that SIB1 for Cell 3 is not included in the RRC rejection, and the RACH configuration for an on-demand SIB1 request for Cell 3 is not included in the RRC rejection. In this case, if SIB1A has the RACH configuration for Cell 3, the UE can request on-demand SIB1 or perform IA (e.g., IA to Cell 3) based on the RACH configuration. As another example, the UE can perform RACH operation after cell reselection to another cell on the same frequency or a cell on a different frequency other than Cell 3. As another example, the UE can maintain a camp-on state on Cell A without cell reselection.

[0462] Example 5

[0463] In one embodiment of the present disclosure, the terminal may receive redirection information via RACH MSG 2, MSG 4 and / or MSG 4 (transmitted via Cell A or Cell 1) while starting RACH for SIB1 request (and / or IA) of Cell 1. Specifically, the terminal may perform operations according to the steps described below.

[0464] Step 1: The terminal can camp on Cell A and receive RACH configuration information for SIB1 request of Cell 1 from the base station through SIB1A broadcasted by Cell A.

[0465] At this time, SIB1 of cell A (e.g., SIB1A) may include / provide a cell list corresponding to on-demand SIB1 (e.g., cells 1, 2, 3, 4), a frequency list for redirection (e.g., ARFCN information of F1, F3, F4), and / or a cell list (e.g., PCI and global cell ID for cells 1, 2, 3). In addition, SIB1A may include information about the frequencies and / or cells (e.g., frequency-specific terminal common cell reselection priority, cell-specific terminal common cell quality offset, etc.).

[0466] The terminal may receive the PBCH of cell 1 from the base station according to embodiment 2. If cell 1 is blocked according to the PBCH instruction, the terminal may consider cell 1 to be blocked for the time indicated by cell A (or, for a fixed specific time period) (e.g., 300 seconds) and may not perform the operations according to the steps described below during that time period. For example, if cell 1 is not blocked according to the PBCH instruction, the terminal may perform the operations according to the steps described below.

[0467] Step 2: The terminal may initiate a RACH requesting SIB1 of Cell 1 based on the RACH configuration information. At this time, the RACH may be a RACH that performs IA while requesting on-demand SIB1 for Cell 1. The RACH may be transmitted / performed using the uplink resources of Cell A or Cell 1.

[0468] Step 3: The terminal may receive redirection information from the base station via MSG 2, B, and / or 4. Here, MSG 2, B, and / or 4 may be transmitted to the terminal via a PDSCH scheduled as a PDCCH. As another example, MSG 2, B, and / or 4 may be transmitted to the terminal via a MAC CE or RRC message.

[0469] Redirection information may include at least one of the following pieces of information:

[0470] - One or more or all of the frequencies listed in SIB1A (e.g., F1, F3, F4);

[0471] - One or more or all cells listed in SIB1A (e.g., cell 2, cell 3, cell 4);

[0472] - Cell reselection priority per terminal for each frequency listed above;

[0473] - Cell quality offset per terminal for each cell listed above;

[0474] - RACH setup for each cell listed above for on-demand SIB1 request or IA;

[0475] - Frequency selection probability values ​​for each frequency in the above list.

[0476] For example, if the base station assigns 0.3, 0.5, and 1 as frequency selection probability values ​​for F1, F3, and F4, the terminal can generate a random number between 0 and 1. If the generated random number is less than 0.3, the terminal can select F1, if the generated random number is between 0.3 and 0.5, the terminal can select F3, and if the generated random number is greater than 0.5, the terminal can select F4.

[0477] The above redirection information may include / set different values ​​and / or different information depending on the terminal type, terminal capability, or terminal service. For example, if the terminal type, terminal capability, or terminal service of the terminal is indicated by MSG1, MSG3, or MSGA, the base station may set redirection information according to the terminal type (e.g., RedCap terminal or general terminal, etc.), terminal capability, or terminal service, and transmit the set redirection information to the base station.

[0478] Step 4: The terminal stores the received redirection information and can perform cell reselection, on-demand SIB1 procedure (e.g., on-demand SIB1 request), and IA operation based on the stored redirection information.

[0479] At this time, the terminal can perform at least one of the following operations:

[0480] - The terminal can store the above redirection information only when the ongoing RACH is successfully terminated;

[0481] - The terminal may receive MSG2, MSGB, or MSB4 from the base station during the ongoing RACH process, or may pass collision resolution (or contention resolution). Additionally or alternatively, the terminal may store the redirection information only when it transmits MSG3 or MSG5 to the base station;

[0482] - If the terminal receives redirection information during RACH, it can immediately store the redirection information (even before RACH termination).

[0483] As an example of the present disclosure, when executing redirection, the terminal may perform at least one of the following operations:

[0484] - If the above RACH is successfully terminated, the terminal can perform cell reselection based on the stored redirection information. The terminal can start RACH for on-demand SIB1 and / or IA in the reselected cell.

[0485] - If the above RACH is terminated due to failure, the terminal may perform cell reselection based on the stored redirection information. The terminal may initiate RACH for on-demand SIB1 and / or IA in the reselected cell.

[0486] - If a message transmitting redirection is successfully received during the above RACH, the UE can perform cell reselection based on the redirection information (regardless of RACH success). The UE can initiate RACH for on-demand SIB1 and / or IA in the reselected cell.

[0487] In the above-described methods of the present disclosure, if the RACH for on-demand SIB1 and / or IA fails in Cell 1, Cell 2, or Cell 3, the UE may consider the corresponding cell to be blocked for the time indicated by Cell A (or for a fixed specific time period) (e.g., 300 seconds) and may not perform the remaining steps during that time period. If the corresponding cell is not blocked according to the PBCH indication, the UE may continue to perform the remaining steps.

[0488] The methods, embodiments or descriptions for implementing the method proposed in the present disclosure may be applied separately, or one or more methods (or embodiments or descriptions) may be applied in combination.

[0489] 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.

[0490] 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 thereof. 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.

[0491] 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.

[0492] Here, the wireless communication technology implemented in the device (100, 200) of the present disclosure may include not only LTE, NR, and 6G, but also Narrowband Internet of Things for low-power communication. At this time, for example, NB-IoT technology may be an example of LPWAN (Low Power Wide Area Network) technology, and may be implemented with standards such as LTE Cat NB1 and / or LTE Cat NB2, and is not limited to the above-described names. Additionally or alternatively, the wireless communication technology implemented in the device (100, 200) of the present disclosure may perform communication based on LTE-M technology. At this time, for example, LTE-M technology may be an example of LPWAN technology, and may be called by various names such as eMTC (enhanced Machine Type Communication). For example, LTE-M technology can be implemented by at least one of various standards such as 1) LTE CAT 0, 2) LTE Cat M1, 3) LTE Cat M2, 4) LTE non-BL (non-Bandwidth Limited), 5) LTE-MTC, 6) LTE Machine Type Communication, and / or 7) LTE M, and is not limited to the above-described names. Additionally or alternatively, the wireless communication technology implemented in the 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.

[0493] The method proposed in this disclosure is explained with a focus on examples applied to 3GPP LTE / LTE-A and 5G systems, but can be applied to various wireless communication systems in addition to 3GPP LTE / LTE-A and 5G systems.

Claims

1. A step of transmitting a first random access channel (RACH) to a base station by a terminal for requesting an on-demand system information block (SIB) of a first cell; A step of receiving, by the terminal, a first response message from the base station, the first response message including redirection information for at least one cell or at least one frequency band; and A method comprising, based on the redirection information, transmitting, by the terminal, to the base station, a second RACH for an on-demand SIB request of a second cell related to a first frequency band among the at least one frequency band or a third cell among the at least one cell.

2. In paragraph 1, An operation of camping on the first cell is performed by the terminal, A method wherein the first RACH is based on configuration information related to the RACH included in system information received from the base station through the first cell.

3. In paragraph 1, A method wherein the first RACH includes information for performing initial access to the first cell.

4. In paragraph 1, The first response message includes message 2, message 4 or message B, A method in which the first response message is transmitted to the terminal via a radio resource control (RRC) message or a medium access control (MEC) control element (CE).

5. In paragraph 1, A method in which a cell reselection operation is performed for the second cell or the third cell based on the redirection information.

6. In paragraph 1, A method wherein the redirection information includes at least one of a cell quality offset for each of the at least one cell, a cell reselection priority for each of the at least one frequency band, and a frequency selection probability for each of the at least one frequency band.

7. In paragraph 6, A method in which the first frequency band among the at least one frequency band is selected by the terminal based on a random value selected by the terminal and a frequency selection probability for the at least one frequency band.

8. In paragraph 6, A method according to claim 1, wherein the on-demand SIB of the first cell comprises at least one of: i) information related to the at least one cell or the at least one frequency band, ii) common cell reselection priority per the at least one cell, or iii) common cell quality offset per the at least one frequency band.

9. In paragraph 1, A method in which, based on the second RACH, the on-demand SIB of the second cell or the third cell is transmitted from the base station to the terminal.

10. In paragraph 1, A method wherein the first cell is an anchor cell, and the second cell or the third cell is a network energy saving (NES) cell.

11. One or more transceivers; and comprising one or more processors connected to said one or more transceivers, One or more of the above processors: Transmitting a first random access channel (RACH) to a base station through one or more transceivers for requesting an on-demand system information block (SIB) of a first cell; Receiving a first response message from the base station through the one or more transceivers, the first response message including redirection information for at least one cell or at least one frequency band; and A terminal configured to transmit a second RACH for an on-demand SIB request of a second cell related to a first frequency band among the at least one frequency band or a third cell among the at least one cell to the base station through the one or more transceivers based on the redirection information.

12. A step of receiving a first random access channel (RACH) from a terminal by a base station for requesting an on-demand system information block (SIB) of a first cell; A step of transmitting, by the base station, to the terminal a first response message including redirection information for at least one cell or at least one frequency band; and A method comprising, based on the redirection information, receiving, by the base station, from the terminal, a second RACH for an on-demand SIB request of a second cell related to a first frequency band among the at least one frequency band or a third cell among the at least one cell.

13. In the base station, the base station: one or more transceivers; and comprising one or more processors connected to said one or more transceivers, One or more of the above processors: Receiving a first random access channel (RACH) for requesting an on-demand system information block (SIB) of a first cell from a terminal through one or more transceivers; Transmitting a first response message containing redirection information for at least one cell or at least one frequency band to the terminal via the one or more transceivers; and A base station configured to receive, from the terminal through the one or more transceivers, a second RACH for an on-demand SIB request of a second cell related to a first frequency band among the at least one frequency band or a third cell among the at least one cell, based on the redirection information.

14. In a processing device configured to control a terminal, the processing device: one or more processors; and A processing device comprising one or more computer memories operatively connected to said one or more processors and storing instructions that, when executed by said one or more processors, perform a method according to any one of claims 1 to 10.

15. One or more non-transitory computer-readable media storing one or more instructions, A computer-readable medium, wherein the one or more commands are executed by one or more processors to control a device to perform a method according to any one of claims 1 to 10.

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