Method performed by terminal or network in wireless communication system, and device therefor

Abstract

A terminal according to one embodiment of the present disclosure can receive at least one synchronization signal (SS) block from among a plurality of SS blocks included in an SS-burst, transmit an uplink signal for an on-demand physical broadcast channel (PBCH) request on the basis of the at least one SS block, and receive, on the basis of the transmission of the uplink signal, at least one PBCH block from among a plurality of PBCH blocks included in a PBCH-burst. An index of the at least one PBCH block received by the terminal is associated with an index of the received at least one SS block, and an uplink resource for the uplink signal can be determined on the basis of (i) the index of the at least one SS block and / or (ii) the index of the at least one PBCH block associated with the index of the at least one SS block.

Description

Method performed by a terminal or network in a wireless communication system and device therefor

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

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

[0003] In 5G NR mobile communication systems, a signal block containing a synchronization signal / physical broadcast channel (SS / PBCH) is referred to as an SSB burst, and multiple SSBs are transmitted via different beams within an SSB burst. In the initial NR version, Rel. 15 NR, SSB bursts were defined as always-on, meaning that transmission was always performed. However, to conserve network energy (NES), a method to provide SSB on-demand upon UE request is being discussed.

[0004] Meanwhile, in next-generation wireless communication systems including 6G, the SSB and SSB burst structures and delivery methods may be newly defined for more efficient transmission and power savings.

[0005] The technical task to be achieved in the present disclosure is to provide a method and a device for efficiently performing a wireless signal transmission and reception process. According to one embodiment, a method is provided for separately configuring an SS burst for a synchronization signal and an SI (e.g., PBCH) burst for system information, and transmitting and receiving system information in the SI (e.g., PBCH) burst in an on-demand manner.

[0006] In addition to the technical challenges described above, other technical challenges can be inferred from the description below.

[0007] According to one aspect of the present disclosure, a method performed by a terminal includes receiving at least one synchronization signal (SS) block among a plurality of SS blocks included in an SS-burst; transmitting an uplink signal for an on-demand physical broadcast channel (PBCH) request based on the at least one SS block; and receiving at least one PBCH block among a plurality of PBCH blocks included in the PBCH-burst based on the transmission of the uplink signal, wherein an index of the at least one PBCH block received by the terminal is linked to an index of the received at least one SS block, and an uplink resource for the uplink signal can be determined based on at least one of (i) an index of the at least one SS block or (ii) an index of the at least one PBCH block linked to an index of the at least one SS block.

[0008] The above plurality of SS blocks may be L SS blocks transmitted from among a maximum of N SS blocks set for the SS burst.

[0009] The plurality of PBCH blocks may include L PBCH blocks linked to the L SS blocks. The terminal may determine to receive a PBCH block having a PBCH block index m among the L PBCH blocks based on receiving an SS block having an SS block index n among the L SS blocks. The uplink resource may be determined based on the PBCH block index m.

[0010] A plurality of uplink resources linked to the above N SS blocks can be set. The terminal can transmit the uplink signal through the uplink resource linked to the SS block index n based on receiving an SS block having an SS block index n among the L SS blocks.

[0011] The power of the above uplink signal can be determined based on a frequency band or synchronization raster of the at least one SS block.

[0012] The above PBCH burst may be the earliest PBCH burst located after a time offset Y from the transmission of the uplink signal among the periodically set PBCH bursts.

[0013] The at least one SS block may include configuration information related to transmission of the uplink signal.

[0014] The above multiple SS blocks may be PBCH-less SS blocks.

[0015] The above uplink signal may include at least one of a wake-up signal (WUS) or a random access channel.

[0016] According to another aspect of the present disclosure, a non-transitory computer-readable recording medium having recorded thereon a program for performing the method described above may be provided.

[0017] According to another aspect of the present disclosure, a device comprises at least one processor; and at least one memory configured to store instructions that are executed by the at least one processor to cause the at least one processor to perform operations, wherein the operations of the processor include receiving at least one synchronization signal (SS) block from among a plurality of SS blocks included in an SS-burst; transmitting an uplink signal for an on-demand PBCH (physical broadcast channel) request based on the at least one SS block; and receiving at least one PBCH block from among a plurality of PBCH blocks included in the PBCH-burst based on the transmission of the uplink signal, wherein an index of the at least one PBCH block received by the device is linked to an index of the received at least one SS block, and an uplink resource for the uplink signal can be determined based on at least one of (i) an index of the at least one SS block or (ii) an index of the at least one PBCH block linked to an index of the at least one SS block.

[0018] The above device may further include a transmitter and receiver.

[0019] The above device may be a terminal.

[0020] The above device may be a processing device configured to control a terminal.

[0021] According to another aspect of the present disclosure, a method performed by a base station includes transmitting at least one synchronization signal (SS) block among a plurality of SS blocks included in an SS-burst; receiving an uplink signal for an on-demand physical broadcast channel (PBCH) request from a terminal; and transmitting at least one PBCH block among the plurality of PBCH blocks included in the PBCH-burst based on reception of the uplink signal, wherein an index of the at least one PBCH block is linked to an index of the at least one SS block, and an uplink resource for the uplink signal can be determined based on at least one of (i) an index of the at least one SS block or (ii) an index of the at least one PBCH block linked to an index of the at least one SS block.

[0022] According to another aspect of the present disclosure, a base station comprises at least one processor; and at least one memory configured to store instructions that are executed by the at least one processor to cause the at least one processor to perform operations, wherein the operations of the processor include transmitting at least one synchronization signal (SS) block among a plurality of SS blocks included in an SS-burst; receiving an uplink signal for an on-demand physical broadcast channel (PBCH) request from a terminal; and transmitting at least one PBCH block among a plurality of PBCH blocks included in the PBCH-burst based on reception of the uplink signal, wherein an index of the at least one PBCH block is linked to an index of the at least one SS block, and an uplink resource for the uplink signal can be determined based on at least one of (i) an index of the at least one SS block or (ii) an index of the at least one PBCH block linked to an index of the at least one SS block.

[0023] According to the present disclosure, signal transmission and reception can be efficiently performed in a wireless communication system. According to one embodiment, by separately configuring an SS burst and an SI (e.g., PBCH) burst for system information, not only can SSB transmission be performed more efficiently, but also system information transmission of the SI (e.g., PBCH) burst can be performed on-demand, thereby enabling more power-efficient operation.

[0024] In addition to the technical effects described above, other technical effects can be inferred from the description below.

[0025] Figure 1 illustrates a flexible network topology to which some examples of this specification may be applied.

[0026] FIG. 2 illustrates an example of a communication system applicable to the present disclosure.

[0027] FIG. 3 illustrates an example of a wireless device applicable to the present disclosure.

[0028] FIG. 4 illustrates a communication procedure between a first node (e.g., a terminal) and a second node (e.g., a base station) applicable to the present disclosure.

[0029] Figure 5 illustrates a general functional architecture for an AI / ML model.

[0030] Figure 6 illustrates a communication procedure between a first node (e.g., terminal) and a second node (e.g., base station) to which an AI / ML model is applied.

[0031] FIG. 7 illustrates an electromagnetic spectrum according to one embodiment of the present disclosure.

[0032] FIG. 8 illustrates an example of a procedure for transmitting system information for THz communication to which the present disclosure applies.

[0033] Figure 9 illustrates a beam management procedure applicable to the present disclosure.

[0034] FIG. 10 illustrates an example of a sensing operation according to one embodiment of the present disclosure.

[0035] FIG. 11 illustrates time / frequency resources for sensing operations according to one embodiment of the present specification.

[0036] FIG. 12 illustrates a procedure related to a sensing operation according to one embodiment of the present specification.

[0037] Figure 13 illustrates an example of the operation procedure of a base station supporting NES technology.

[0038] Figure 14 illustrates an example of a procedure for cell DTX / DRX operation.

[0039] Figure 15 illustrates an example of a procedure for CA operation using SSB-less SCell.

[0040] Figure 16 illustrates an example of a conditional handover (CHO) procedure.

[0041] Figure 17 illustrates an example of on-demand SSB transmission.

[0042] Figure 18 illustrates an SSB pattern (SSB burst) when the maximum number of SSB indices is 8.

[0043] Figure 19 shows an example of an SS( / SI-0) burst and a WO burst.

[0044] Figures 20 and 21 illustrate SS burst transmission and SI-0 burst transmission according to various embodiments.

[0045] FIG. 22 illustrates an SS Burst, an SI-0 burst, and a WO burst according to one embodiment.

[0046] Figure 23 is a drawing for explaining the operation of a terminal and a base station according to one embodiment.

[0047] Figure 24 illustrates a flow of a method performed by a terminal according to one embodiment.

[0048] Figure 25 illustrates a flow of a method performed by a terminal according to one embodiment.

[0049] As used herein, "A or B" can mean "only A," "only B," or "both A and B." In other words, as used herein, "A or B" can be interpreted as "A and / or B." For example, as used herein, "A, B or C" can mean "only A," "only B," "only C," or "any combination of A, B and C."

[0050] As used herein, a slash ( / ) or a comma can mean "and / or." For example, "A / B" can mean "A and / or B." Accordingly, "A / B" can mean "only A," "only B," or "both A and B." For example, "A, B, C" can mean "A, B, or C."

[0051] In this specification, "at least one of A and B" may mean "only A", "only B" or "both A and B". Additionally, in this specification, the expressions "at least one of A or B" or "at least one of A and / or B" may be interpreted identically to "at least one of A and B".

[0052] Additionally, in this specification, “at least one of A, B and C” can mean “only A,” “only B,” “only C,” or “any combination of A, B and C.” Additionally, “at least one of A, B or C” or “at least one of A, B and / or C” can mean “at least one of A, B and C.”

[0053] Additionally, parentheses used herein may mean "for example." Specifically, when "control information (ABC)" is indicated, "ABC" may be described as an example of "control information." For example, "control information" may include DEF as another example. In other words, "control information" in this specification is not limited to "ABC," and "ABC" may be described as an example of "control information." Furthermore, even when indicated as "control information (i.e., ABC)," "ABC" may be described as an example of "control information."

[0054] Additionally, in this specification, terms such as “first,” “second,” etc. are used only for the purpose of distinguishing one component from another component and are not used to limit the components, and do not limit the order or importance between the components unless specifically limited. Accordingly, a first component in one embodiment of this specification 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.

[0055] In the following explanation, ‘when, if, in case of’ can be replaced with ‘based on’.

[0056] Technical features individually described in a single drawing in this specification may be implemented individually or simultaneously.

[0057] In this specification, a terminal is a user equipment (UE) or a consumer-side device, and may also be referred to as a base station / second node / IAB node / first node that receives / transmits signals from / to a Transmission-Reception Point (TRP). A terminal may correspond to a physical node or a logical node. A terminal may correspond to an endpoint on the user side, or may correspond to an intermediate point between other endpoints. In communication between two points that are not limited to endpoints (including one-to-one / many-to-one / one-to-many / many-to-many communication), a terminal may correspond to a served node. A terminal may be a node with a fixed location, or a node with an unfixed location (or mobile).

[0058] In this specification, a base station (BS) is a device on the network side, and may also be called a second node / IAB node / x-NodeB (x-NodeB, x may be an abbreviation related to radio access technology (RAT)) / Transmission-Reception Point (TRP). A BS may correspond to a physical node or a logical node. A BS may correspond to an endpoint on the network side, or may correspond to an intermediate point between other endpoints. In communication between two points that are not limited to endpoints (including one-to-one / many-to-one / one-to-many / many-to-many communication), a BS may correspond to a serving node. A BS may be a node with a fixed location, or a node with an unfixed location.

[0059] In this specification, higher layer parameters may be set for the terminal, preset, or predefined. For example, the base station may transmit higher layer parameters to the terminal. For example, the terminal may transmit parameters such as capabilities to the base station as higher layer parameters. For example, the higher layer parameters may be transmitted via radio resource control (RRC) signaling or medium access control (MAC) signaling.

[0060] In this specification, the information / state / parameter being “configured or pre-configured” can be interpreted as the information / state / parameter being provided / pre-provided to the terminal through pre-defined signaling (e.g., SIB, MAC, RRC) from the base station. In this specification, the information / state / parameter being “defined or pre-defined” can be interpreted as the information / state / parameter being known in advance or pre-stored at the base station and the terminal without signaling between the base station and the terminal.

[0061] The technology described in this specification 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.

[0062] The technology described in this specification 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.

[0063] <Symbols, Abbreviations, Terms>

[0064] - PDCCH: Physical Downlink Control CHannel

[0065] - DCI: Downlink Control Information

[0066] - PDSCH: Physical Downlink Shared CHannel

[0067] - PUSCH: Physical Uplink Shared CHannel

[0068] - CSI: Channel state information

[0069] - RRM: Radio resource management

[0070] - SCS: Sub-carrier spacing

[0071] - RLM: Radio link monitoring

[0072] - DCI: Downlink Control Information

[0073] - CAP: Channel Access Procedure

[0074] - Ucell: Unlicensed cell

[0075] - TBS: Transport Block Size

[0076] - TDRA: Time Domain Resource Allocation

[0077] - SLIV: Starting and Length Indicator Value (This is an indicator value for the starting symbol index and number of symbols within the slot of the PDSCH and / or PUSCH, and can be set as a component of the entry that constitutes the TDRA field within the PDCCH that schedules the corresponding PDSCH and / or PUSCH.)

[0078] - BWP: BandWidth Part (can be composed of consecutive resource blocks (RBs) on the frequency axis and can correspond to one numerology (e.g., sub-carrier spacing, CP length, slot / mini-slot duration). In addition, multiple BWPs can be configured on one carrier (the number of BWPs per carrier can also be limited), but the number of activated BWPs can be limited to a part of it (e.g., 1) per carrier.)

[0079] - CORESET: COntrol REsourse SET (refers to the time-frequency resource area where PDCCH can be transmitted, and the number of CORESETs per BWP may be limited.)

[0080] - REG: Resource element group

[0081] - SFI: Slot Format Indicator (An indicator indicating the symbol level DL / UL direction within a specific slot(s), transmitted through the group common PDCCH.)

[0082] - COT: Channel occupancy time

[0083] - SPS: Semi-persistent scheduling

[0084] - QCL: Quasi-Co-Location (QCL relationship between two reference signals means that QCL parameters such as Doppler shift, Doppler spread, average delay, delay spread, and Spatial Rx parameter obtained from one reference signal can be applied to another reference signal (or antenna port(s) of the corresponding RS). In the NR system, four QCL types are defined as follows. 'typeA': {Doppler shift, Doppler spread, average delay, delay spread}, 'typeB': {Doppler shift, Doppler spread}, 'typeC': {Doppler shift, average delay}, 'typeD': {Spatial Rx parameter} For any DL RS antenna port(s), the first DL RS is set as a reference for QCL type X (X=A, B, C, or D), and additionally, the second DL RS is set as a reference for QCL type Y (Y=A, B, C, or D but X≠Y). (can be set as a reference for .)

[0085] - TCI: Transmission Configuration Indication (A TCI state includes the QCL relationship between one or more DL RSs, such as DM-RS ports of the PDSCH, the DM-RS port of PDCCH, or the CSI-RS port(s) of a CSI-RS resource. For the 'Transmission Configuration Indication' field in the DCI that schedules the PDSCH, the TCI state index corresponding to each code point that constitutes the field is activated by the MAC CE, and the TCI state setting for each TCI state index is set through RRC signaling. In the Rel-16 NR system, the TCI state is set between DL RSs, but in future releases, setting between DL RS and UL RS or UL RS and UL RS may be allowed. Examples of UL RSs include SRS, PUSCH DM-RS, and PUCCH DM-RS.)

[0086] - SRI: SRS resource indicator (Indicates one of the SRS resource index values ​​set in the 'SRS resource indicator' among the fields in the DCI that schedules the PUSCH. When transmitting a PUSCH, the UE can transmit the PUSCH using the same spatial domain transmission filter used for transmitting and receiving the reference signal linked to the corresponding SRS resource. At this time, the reference RS is set by RRC signaling through the SRS-SpatialRelationInfo parameter for each SRS resource, and SS / PBCH block, CSI-RS, or SRS can be set as the reference RS.)

[0087] - TRP: Transmission and Reception Point

[0088] - TAG: Timing advance group

[0089] - PLMN: Public Land Mobile Network

[0090] Figure 1 illustrates a flexible network topology to which some examples of this specification may be applied.

[0091] 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 IAB nodes, relays, and RF repeaters, as illustrated in the example in Figure 1, may be applied, or NTNs 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, or 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, while a network-controlled repeater may not only amplify and forward signals but also adjust transmission and reception settings based on information provided by the network. For example, an NTN node may correspond to a satellite or aircraft that provides NTN coverage that is difficult for terrestrial networks to provide. In addition to these examples, various intermediate points can be introduced to improve the network topology.

[0092] 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.

[0093] 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. In other words, 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.

[0094] In some examples of this specification, the description of a terminal can be equally applied 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 this specification, the description of a base station can be equally applied 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. However, in most cases where there is no additional description of the operations of three or more entities, the communicating entities in this specification are briefly described as terminals and / or base stations (or first nodes and / or second nodes), and 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.

[0095] That is, in some examples of this specification, for the sake of simplicity of explanation, the subjects of the operation may be referred to as a base station and / or a terminal (or a first node and / or a second node). In addition, the terms base station and / or terminal (or a first node and / or a second node) may also be interpreted / replaced as in the following examples: For example, the base station (or a first node) and the terminal (or a 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.

[0096] In this specification, there may be zero or more intermediate points between the base station and the terminal. If intermediate points exist, they may be IAB nodes, relays, RF repeaters, NTN (non-terrestrial network) nodes, or nodes supporting other functions. An intermediate point may be a node with a fixed location or a node with an unfixed location.

[0097] Figure 2 illustrates a communication system applicable to the present disclosure.

[0098] The communication system (100) of FIG. 2 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, a 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).

[0099] 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, IoT devices (110f) (e.g., sensors) can communicate directly with other IoT devices (e.g., sensors) or other wireless devices (110a to 110f).

[0100] 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.

[0101] FIG. 3 illustrates an example of a wireless device applicable to the present disclosure.

[0102] 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).

[0103] 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.

[0104] 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) including 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.

[0105] At least one processor (202) may be referred to as a controller, a microcontroller, a microprocessor, or a microcomputer. The at least one processor (202) may be implemented by hardware, firmware, software, or a combination thereof. For example, at least one application specific integrated circuit (ASIC), at least one digital signal processor (DSP), at least one digital signal processing device (DSPD), at least one programmable logic device (PLD), or at least one field programmable gate array (FPGA) may be included in the at least one processor (202). The descriptions, functions, procedures, proposals, methods, and / or operation flowcharts disclosed in this document may be implemented using firmware or software, and the firmware or software may be implemented to include modules, procedures, functions, etc. The descriptions, functions, procedures, proposals, methods, and / or operation flowcharts disclosed in this document may be included in the at least one processor (202), or may be stored in at least one memory (204) and executed by the at least one processor (202). The descriptions, functions, procedures, suggestions, methods and / or flowcharts disclosed in this document may be implemented using firmware or software in the form of code, instructions and / or sets of instructions.

[0106] 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.

[0107] 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. In addition, 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 operation flowcharts disclosed in this document through at least one antenna (208). In this document, at least one antenna may be a plurality of physical antennas or a plurality of logical antennas (e.g., antenna ports). At least one transceiver (206) may convert the received wireless signals / channels, etc. from RF band signals to baseband signals in order to process the received user data, control information, wireless signals / channels, etc. using at least one processor (202). At least one transceiver (206) may convert the processed user data, control information, wireless signals / channels, etc. from baseband signals to RF band signals using at least one processor (202).For this purpose, at least one transceiver (206) may include an (analog) oscillator and / or filter.

[0108] 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).

[0109] 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.

[0110] 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.

[0111] 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.

[0112] 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.

[0113] 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.

[0114] 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.

[0115] 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. However, if the front haul and / or back haul communications are based on wireless communications, at least one transceiver (206) illustrated in FIG. 3 may be used for front haul and / or back haul communications, and a wired transceiver may not be included.

[0116] FIG. 4 illustrates a communication procedure between a first node (e.g., a terminal) and a second node (e.g., a base station) applicable to the present disclosure.

[0117] The second node of FIG. 4 supports dynamic spectrum sharing (DSS), which can provide connectivity to both nodes implementing 6G technology and nodes implementing pre-6G wireless communication technologies (e.g., 5G, 4G). That is, the first node of FIG. 4 can implement either 6G technology or pre-6G wireless communication technologies (e.g., 5G, 4G). Furthermore, the first node and / or the second node can support full duplex mode as well as non-overlapping full duplex mode.

[0118] In Fig. 4, for the sake of simplicity of explanation, the first node and the second node are assumed to be a terminal and a base station, respectively, and operations of the terminal (110) and the base station (120) transmitting and / or receiving data and operations performed prior thereto are illustrated. However, the operations of Fig. 4 are not limited to operations between the terminal and the base station, and may be interpreted as operations between the first node and the second node. In addition, although Fig. 4 illustrates direct wireless signal transmission and reception operations between the terminal (110) and the base station (120), one or more intermediate points may exist between the terminal (110) and the base station (120), and wireless signals may be transmitted and received via one or more intermediate points.

[0119] Referring to FIG. 4, the terminal (110) and the base station (120) can perform synchronization (401). For example, the terminal (110) performs an initial cell search operation. Specifically, the terminal (110) can detect a synchronization signal for connection to at least one base station transmitted from the base station (120) according to a predefined rule. Here, the synchronization signal can include a plurality of synchronization signals classified according to structure or purpose (e.g., a first synchronization signal (e.g., a primary synchronization signal), a second synchronization signal (e.g., a secondary synchronization signal), etc.). Through this, the terminal (110) can confirm the boundary of a unit (e.g., a frame, a subframe, a slot, and / or a symbol) constituting a wireless signal transmission of the base station (120) and obtain information (e.g., a cell identifier) ​​about the base station (120).

[0120] The terminal (110) can obtain system information transmitted from the base station (120) (403). The system information is information related to the properties, characteristics, and / or capabilities of the base station (120) required to access the base station (120) and use the service, and can be classified according to the content (e.g., whether it is essential for access), transmission structure (e.g., channel used, whether provided on-demand), etc., and can be classified into, for example, first system information (e.g., master information block (MIB), primary system information), second system information (e.g., system information block (SIB), secondary system information), etc. If necessary, the terminal (110) can transmit a signal requesting system information before receiving the system information. However, the request and provision of system information can be performed after the random access procedure described below.

[0121] The terminal (110) and the base station (120) can perform a random access procedure (405). 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 the random access procedure based on information related to a channel for the random access procedure of the base station (120) obtained through system information (e.g., channel location, channel structure, structure of a supported preamble, etc.). For example, the terminal (110) can transmit a first message (e.g., a preamble, MSG1) through the channel for the random access procedure, receive a second message (e.g., an RAR message, MSG2), transmit a third message (e.g., MSG3) including information related to the terminal (110) (e.g., identification information) to the base station (120) using scheduling information included in the second message, and receive a fourth message (e.g., MSG4) for contention resolution and / or connection establishment. As another example, the first and third messages may be sent and received as one message, or the second and fourth messages may be sent and received as one message.

[0122] The terminal (110) and the base station (120) can perform signaling of control information (407). Here, 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 transport 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.

[0123] The terminal (110) and the base station (120) can transmit and / or receive data (409). In other words, 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 the information bits. Conversely, 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.

[0124] <6G System Core Technologies>

[0125] The 6G (wireless) system aims to provide (i) very high data rates per device, (ii) a very large number of connected devices, (iii) global connectivity, (iv) very low latency, (v) low energy consumption for battery-free 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.

[0126] As core implementation technologies of the 6G system, technologies such as artificial intelligence (AI), THz (terahertz) communication, optical wireless technology, FSO backhaul network, massive MIMO technology, blockchain, 3D networking, quantum communication, unmanned aerial vehicles, cell-free communication, wireless information and energy transfer (WIET), integration of sensing and communication, integration of access backhaul networks, holographic beamforming, big data analysis, and large intelligent surface (LIS) can be adopted.

[0127] artificial intelligence

[0128] Incorporating AI into communications can streamline and improve real-time data transmission. AI can use numerous analytics to determine how complex target tasks should be performed. This means AI can increase efficiency and reduce processing delays. Time-consuming tasks such as handovers, network selection, and resource scheduling can be performed instantly using AI. AI can also play a crucial role in machine-to-machine (M2M), machine-to-human, and human-to-machine communications. Furthermore, AI can facilitate rapid communication in brain-computer interfaces (BCIs). AI-based communication systems can be supported by metamaterials, intelligent structures, intelligent networks, intelligent devices, intelligent cognitive radios, self-sustaining wireless networks, and machine learning.

[0129] The following describes a functional framework for AI / ML operations.

[0130] Below, to explain AI (or AI / ML) more specifically, the terms can be defined as follows.

[0131] - Data collection: Data collected from network nodes, management entities, or terminals as a basis for AI model training, data analysis, and inference.

[0132] - 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.

[0133] - 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.

[0134] - AI / ML Inference: The process of making predictions or inducing decisions based on collected data and the AI ​​model using a trained AI model.

[0135] Life Cycle Management (LCM) procedures for AI / ML models (i.e., model training, model deployment, model inference, model monitoring, model updates, etc.) can be divided into functionality-based LCM and model-based LCM. In functionality-based LCM, AI / ML models may not be identified by the network, and the network can direct the activation / deactivation / fallback / switching of AI / ML functionality. In model-ID (identifier)-based LCM, AI / ML models can be identified by the network, and the network / terminal can activate / deactivate / select / switch AI / ML models based on the model ID.

[0136] Figure 5 illustrates a general functional architecture for an AI / ML model.

[0137] In particular, Figure 5 illustrates a general functional architecture relevant to both Functionality-based LCM and Model-based LCM. Some of the functions or some of the data / information / command flows (i.e., arrows) illustrated in Figure 5 may be omitted.

[0138] Referring to FIG. 5, a general functional framework can be configured to include a data collection function (10), a model training function (20), a management function (30), an inference function (40), and a model storage function (50).

[0139] The Data Collection function (10) is a function that provides input data to the Model Training function (20), Management function (30), and Inference function (40). The Data Collection function (10) can perform data preparation based on raw data and provide input data processed through data preparation. Examples of raw data may include received data / measurement data from terminals or other network entities, inference / output of AI / ML models, etc. The Data Collection function (10) may be performed by a single entity (e.g., a terminal, a network node, etc.) or may be performed by multiple entities.

[0140] Here, training data (11) refers to data required as input for the AI / ML Model Training function (20). Monitoring data (12) refers to data required as input for the Management (30) of the AI / ML model or AI / ML function. Inference data (13) refers to data required as input for the AI / ML Inference function (30).

[0141] The Model Training function (20) is a function that performs AI / ML model training, validation, and testing, which can generate model performance metrics that can be used as part of the AI / ML model testing procedure. The Model Training function (20) can perform data preparation (e.g., data pre-processing and cleaning, forming, and transformation) based on the Training Data (11) transferred from the Data Collection function (10), if necessary.

[0142] Trained / Updated Model (21): If there is a Model Storage function (50), it is used to pass a trained, validated and tested AI / ML model to the Model Storage function (50) or to pass an updated version of the model to the Model Storage function (50).

[0143] The Management function (30) is a function that supervises the operation of the AI / ML model or AI / ML function. In addition, the Management function (30) may perform decisions to ensure appropriate inference operations based on data received from the Data Collection function (10) (i.e., Monitoring Data (12)) and / or data received from the Inference function (40) (i.e., Inference Output (41)).

[0144] Management Instruction (32) is information required as input to manage the Inference function (40). The relevant information may include selection / (de)activation / switching of an AI / ML model or AI / ML-based function, and may also include fallback to non-AI / ML operations (i.e., not relying on the inference process).

[0145] A Model Transfer / Delivery Request (33) can be used to request model(s) from Model Storage (50).

[0146] A Performance Feedback / Retraining Request (31) refers to information required as input to the Model Training function (20) (e.g., for the purpose of (re)training or updating the model).

[0147] The Inference function (40) is a function that provides output from the process of applying an AI / ML model or AI / ML function using data (i.e., Inference Data (13)) provided by Data Collection (10) as input. Data preparation (e.g., data preprocessing and cleaning, formatting, and transformation) may also be performed based on the Inference Data (13) delivered by Data Collection (10). If necessary, the Inference function (40) may also perform data preparation (e.g., data preprocessing and cleaning, forming, and transformation) based on the Inference Data (13) provided by Data Collection function (10).

[0148] Inference Output (41) is data used in the Management function (30) to monitor the performance of an AI / ML model or AI / ML function. Inference Output (41) may include the inference output of the AI / ML model generated by the Inference function (30), and the details of the inference output may vary depending on the use case.

[0149] The Model Storage function (50) stores a learned / updated model that can be used to perform the Inference function (40). The Model Storage function (50) illustrated in FIG. 5 can be used as a reference point (if any) when applicable to protocol termination, model transmission / delivery, and related processes. Furthermore, the Model Storage function (50) is merely an example and is not intended to limit the storage location of actual AI / ML models, and may be omitted.

[0150] Model Transfer / Delivery (51) is used to transfer AI / ML models to inference functions.

[0151] The level of cooperation can be defined as follows depending on the capability of AI / ML functions between multiple nodes, and variations due to combination of multiple levels or separation of any one level are also possible.

[0152] Cat 0a) No collaboration framework: AI / ML algorithms are purely implementation-based and do not require any changes to the wireless interface.

[0153] Cat 0b) This level corresponds to a framework with a modified wireless interface tailored to efficient implementation-based AI / ML algorithms, but without collaboration.

[0154] Category 1) involves inter-node support to improve the AI / ML algorithms of each node. For example, this applies when a specific node receives support from another node (for training, adaptation, etc.) and vice versa. At this level, model exchange between network nodes is not required.

[0155] Category 2) Joint AI / ML tasks can be performed across multiple nodes. This level requires the exchange of AI / ML model commands or network nodes.

[0156] FIG. 5 is a diagram illustrating an overall functional framework for an AI / ML model, and not all functions and / or all data / information / command signals illustrated in FIG. 5 may be performed within a specific node, but only some of them may be performed.

[0157] AI / ML models can be divided into one-side models and two-side models depending on whether training and / or inference are performed on a single node or jointly / sequentially on multiple nodes.

[0158] A one-side model can refer to an AI / ML model in which inference is performed entirely by a single node (e.g., a terminal or network). Here, AI / ML model training can also be performed entirely by a single node. AI / ML model training and inference can be performed by the same node, or they can be performed by separate nodes.

[0159] A two-side model can refer to an AI / ML model in which joint inference is performed across multiple nodes (e.g., terminals and networks). Joint inference refers to inference being performed jointly across multiple nodes. For example, the first part of the inference may be performed by a first node, and the remaining part by a second node. Two-side models can be categorized into several types depending on the training method of the AI / ML model, as follows:

[0160] - First type: AI / ML models can be trained on a single node. In this case, joint training can be performed. The trained model can then be distributed to other nodes / objects.

[0161] - Second type: Joint training of AI / ML models can be performed on multiple nodes / entities (e.g., networks and terminals). Joint training can mean that model generation (e.g., CSI generation part) and model reconstruction (CSI compression by sub-use case) are trained in the same loop for forward activation and backward gradient. In this type, joint training can include both simultaneous training (i.e., model generation training and model reconstruction training are performed simultaneously) and sequential training (i.e., model reconstruction training is performed after model generation training).

[0162] - Third type: Separate training of AI / ML models can be performed on multiple nodes (e.g., networks and terminals). Separate training may mean that training begins sequentially on one node and continues on other nodes. In this case, the first node first performs the AI / ML model and shares the training data with the second node. The second node can then use the shared training data to perform the AI / ML model. For example, training for the CSI generation part may be performed by the terminal, while CSI reconstruction may be performed by the network.

[0163] Figure 6 illustrates a communication procedure between a first node (e.g., terminal) and a second node (e.g., base station) to which an AI / ML model is applied.

[0164] The operations described below can be described / interpreted based on the AI / ML model proposed in this specification, as shown in Fig. 6 below, even without separate mention (i.e., without explicit mention of being by / based on / for the AI / ML model). In addition, unless specifically limited, the AI / ML model can correspond to a one-side model in which inference is entirely performed by a single node, or a two-side model in which joint inference is performed by multiple nodes.

[0165] First signaling (601): In the description below, the signaling (e.g., information / data / channel / signal, etc.) or set of signaling between a specific node (e.g., terminal, network, etc.) and another node may be interpreted as the signaling or set of signaling of the first signaling (601) used to perform an operation based on an AI / ML model, even if not otherwise mentioned. For example, it may correspond to training data for training (i.e., generation and / or reconstruction) the AI / ML model of FIG. 5, or correspond to inference data used for inference of the AI / ML model, or correspond to feedback for the AI / ML model, etc. If signaling between nodes is not required prior to an operation based on an AI / ML model in the present specification, the first signaling (601) may be omitted. If a one-side model is used in the present specification, the one-way / two-way signaling (set) in the present specification may correspond to the signaling of the first signaling (601). In addition, when a two-side model is used in this specification, the one-way / two-way signaling in this specification may correspond to the first signaling (601), and also, a repetitive signaling operation may correspond to the first signaling (601).

[0166] For example, in AI / ML model-based beam management (BM), if a base station predicts (i.e., infers) beam(s) with good quality based on an AI / ML model, the base station can receive quality / intensity information for multiple beams from a terminal. Furthermore, if a terminal predicts (i.e., infers) beam(s) with good quality based on an AI / ML model, the terminal can receive multiple beams from the base station.

[0167] AI / ML model-based operation (602): In the description below, an operation (e.g., calculation, selection, prediction, etc.) in a specific node (e.g., terminal, network, etc.) or a joint operation (e.g., calculation, selection, prediction, etc.) in multiple nodes (e.g., terminal, network, etc.) may correspond to an AI / ML model-based operation (602) based on one or more functions in the functional framework of the AI / ML model, even if not mentioned separately. For example, it may correspond to training (i.e., generation and / or reconstruction) of the AI / ML model of FIG. 5 or inference of the AI / ML model, etc. When a one-side model is used, an operation performed by a single node in the present specification may correspond to an AI / ML model-based operation (602), and also, when a two-side model is used, a joint operation performed by multiple nodes in the present specification may correspond to an AI / ML model-based operation (602).

[0168] For example, in an AI / ML model-based BM, the base station can use quality / intensity information for multiple beams received from the terminal as inference data to predict (i.e., infer) beam(s) with good quality based on the AI / ML model. Furthermore, the terminal can measure multiple beams received from the base station and use the measurement results as inference data to predict (i.e., infer) beam(s) with good quality based on the AI / ML model.

[0169] Second signaling (603): In the description below, signaling (e.g., information / data / channel / signal, etc.) or a set of signaling between a specific node (e.g., terminal, network, etc.) and another node may be interpreted as a second signaling (603) or a set of signaling generated due to (as a result of) an operation based on an AI / ML model, even if not otherwise mentioned. For example, it may correspond to an output resulting from inference of the AI / ML model in FIG. 5. If signaling between nodes is not required as a result of an operation based on an AI / ML model in this specification, the second signaling (603) may be omitted. If a one-side model is used in this specification, a one-way / two-way signaling (set) in this specification may correspond to the second signaling (603). In addition, when a two-side model is used in this specification, the one-way / two-way signaling in this specification may correspond to the second signaling (603), and also, a repetitive signaling operation may correspond to the second signaling (603).

[0170] For example, in an AI / ML model-based BM, the base station can transmit to the terminal the beam(s) predicted based on the AI / ML model as candidates so that the terminal can determine the optimal beam. Furthermore, the terminal can report to the base station the beam(s) predicted based on the AI / ML model to request the base station to transmit the candidate beams as candidates for determining the optimal beam.

[0171] THz communication (terahertz communication)

[0172] Data 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 (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 the capacity of 6G cellular communications. 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.

[0173] Figure 7 illustrates the electromagnetic spectrum according to one embodiment of the present disclosure. The embodiment of Figure 7 can be combined with various embodiments of the present disclosure. Key characteristics of THz communications include (i) a widely available bandwidth to support very high data rates, and (ii) high path loss at high frequencies (highly directional antennas are essential). The narrow beamwidth generated by the highly directional antenna reduces interference. The small wavelength of THz signals allows for a much 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 techniques to overcome range limitations.

[0174] Transmitting system information (i.e., information related to the properties, characteristics, and / or capabilities of a BS required to use a service, such as MIB, SIB, etc.) in the THz frequency band may be inefficient because, as the beam width becomes narrower in high frequency bands, more beam sweeps must be performed to cover the entire area of ​​the cell. In particular, transmitting system information in this manner is even more inefficient when there are not many users in the cell. Accordingly, a system information transmission procedure such as that illustrated in FIG. 8 may be used.

[0175] Figure 8 illustrates an example of a procedure for transmitting system information for THz communications to which the present disclosure applies. While this example was developed with THz in mind, it is also applicable to 6G communication environments where THz is not applicable. Furthermore, the procedure illustrated in Figure 8 can be combined with various embodiments of the present disclosure described below. For example, the embodiments described below can be performed based on system information acquired through the procedure illustrated in Figure 8.

[0176] Referring to FIG. 8, the base station can transmit system information of cell #1 through cell #2 (801). That is, the base station provides at least two cells, cell #1 uses a THz frequency band, and cell #2 uses a non-THz frequency band. Here, the system information can include at least one information / state / parameter / setting generated in each of a higher layer and a physical layer. For example, the at least one information / state / parameter / setting generated in the higher layer can include at least one of an SFN, control information setting for SIB1 (e.g., PDCCH configuration for SIB1, etc.), information related to cell selection / entry (e.g., cell barring, cell re-selection, etc.), and subcarrier spacing, and the at least one information / state / parameter / setting generated in the physical layer can include at least one of an SFN, a half frame indicator, and an SSB index. However, this is merely an example, and system information may include information / status / parameters / settings related to Cell #1 / Cell #2 generated from various types of physical layers / upper layers. For this purpose, as an example, Cell #1 and Cell #2 may have a relationship as a secondary cell and a primary cell.

[0177] The UE can acquire synchronization for cell #1 (803). Synchronization can be acquired by detecting a synchronization signal. Typically, synchronization is acquired before receiving system information. However, since the system information for cell #1 is received from cell #2, synchronization acquisition for cell #1 can be performed after receiving the system information. For example, the UE can acquire synchronization based on the system information. However, unlike FIG. 8, in another example, synchronization acquisition can be performed before step 801.

[0178] The UE may transmit a signal for accessing cell #1 (805). For example, the signal may include information for accessing cell #1 (e.g., a random access preamble). The structure of the signal and the resources for transmitting the signal (e.g., a channel) may be identified through system information. Thereafter, the UE and the base station may perform an access procedure for cell #1 and communicate (807). During this process, operations according to various embodiments described below may be performed.

[0179] The procedure described with reference to FIG. 8 may be performed when UE (801) first accesses cell #1 of the base station. Alternatively, a similar procedure may be performed when UE (801) hands over to cell #1 of the base station. 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 base station.

[0180] Communications in the THz band are expected to experience extremely severe path loss, and to overcome this, terminals and base stations must use extremely 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 the movement or movement of the terminals, frequent re-alignment of the beams is required, which can lead to link instability. Accordingly, a beam management procedure, as illustrated in FIG. 9 below, may be employed.

[0181] FIG. 9 illustrates a beam management procedure applicable to the present disclosure. FIG. 9 illustrates an example of a procedure for searching and / or selecting beams for THz communication, but is not limited to a THz environment, and the present disclosure is applicable to a 6G communication environment. In addition, the procedure illustrated in FIG. 9 can be combined with various embodiments of the present disclosure described below. Here, a beam may be interpreted as 'spatial (setting) information', 'spatial domain filter', 'spatial domain transmission filter', 'spatial domain reception filter', or / and a term having an equivalent technical meaning that can distinguish the beam (e.g., Reference signal, SSB (Synchronization Signal Block) Index, TRP (transmission reception point), panel, cell, TP (transmission point), base station, control resource related information (e.g., CORESET (control resource set) related information, etc.).

[0182] Referring to FIG. 9, a base station can configure resources for beam management (901). 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 existing downlink signals / channels 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 existing downlink signals / channels (e.g., synchronization signals (e.g., SSB, etc.), data channels (e.g., PDSCH, 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. That is, a signal transmitted based on a dedicated port defined / configured for beam search can be included in the technical concept according to the present embodiment.

[0183] The base station can transmit measurement signals using multiple transmission beams (903). For example, the measurement signals can include at least one of a reference signal and a synchronization signal. At this time, the measurement signals can be transmitted as many times as the number of beams that require measurement, and can be transmitted using a multi-beam transmission method that forms multiple beams simultaneously to reduce sweeping time. Here, the multi-beam transmission can be performed based on at least one of a multi-panel, a sub-array, and a true time delay (TTD).

[0184] The UE may transmit a feedback signal to the base station (905). The feedback signal indicates at least one beam selected by the UE. The UE may select at least one preferred beam based on the received measurement signals. The UE and the base station may communicate (907). At this time, the UE and the base station may communicate using the previously selected beam. If channel reciprocity is established, the transmission beam of the UE may also be determined through operations 903 and 905, and thus the transmission of the UE may also be performed using the beam selected in operation 905. If channel reciprocity is not established, a procedure including transmission of measurement signals by the UE and transmission of a feedback signal by the base station may be performed first to determine the transmission beam of the UE. In operation 907, operations according to various embodiments described below may be performed.

[0185] Integrated Sensing and Communication (ISAC)

[0186] Wireless sensing is a technology that uses radio frequencies to determine the instantaneous linear velocity, angle, distance (range), etc. of an object, thereby obtaining 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, i.e., 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 communication network to a wireless communication and sensing network.

[0187] FIG. 10 illustrates an example of a sensing operation according to an embodiment of the present disclosure. The embodiment of FIG. 10 can be combined with various embodiments of the present disclosure. Specifically, FIG. 10(a) illustrates an example of sensing using a sensing receiver and a sensing transmitter located at the same location (e.g., monostatic sensing), and FIG. 10(b) illustrates an example of sensing using a separated sensing receiver and sensing transmitter (e.g., bistatic sensing).

[0188] For example, in a wireless communication system based on a 6G network of the present specification, referring to FIG. 10(a), the sensing transmitter and the sensing receiver may be configured to be included in a single base station (i.e., the same base station) or a single terminal (i.e., the same terminal). Alternatively, referring to FIG. 10(b), the sensing transmitter and the sensing receiver may be configured to be included in different base stations, different terminals, or each terminal and base station.

[0189] In this regard, the following six types of sensing modes can be defined based on whether the sensing transmitter and sensing receiver are included in the base station or the terminal, respectively.

[0190] - Mode 1: A mode in which the sensing transmitter and sensing receiver are contained in a single base station (e.g., base station-based sensing mode in monostatic mode).

[0191] - Second mode: A mode in which the sensing transmitter is included in a first base station and the sensing receiver is included in a second base station different from the first base station (e.g., base station-based sensing mode in bistatic mode).

[0192] - Mode 3: A mode in which the sensing transmitter is included in the base station and the sensing receiver is included in the terminal (e.g., base station-terminal sensing mode).

[0193] - Mode 4: A mode in which the sensing transmitter is included in the terminal and the sensing receiver is included in the base station (e.g., terminal-base station sensing mode).

[0194] - Mode 5: A mode in which the sensing transmitter and sensing receiver are contained in a single terminal (e.g., terminal-based sensing mode in monostatic mode).

[0195] - 6th mode: A mode in which the sensing transmitter is included in a first terminal and the sensing receiver is included in a second terminal different from the first terminal (e.g., terminal-based sensing mode in bistatic mode).

[0196] In a wireless communication system based on a 6G network of the present specification, one or more of the six types of sensing modes described above may be utilized independently / in combination.

[0197] In relation to the sensing operation in FIG. 10, the sensing transmitter may transmit a sensing signal for sensing one or more objects (and / or an environment around the objects). For example, the sensing signal may correspond to a radio (frequency) signal defined to be transmittable by a base station / terminal in a wireless communication system based on a 6G network of the present specification. The sensing receiver may receive a signal scattered / reflected by one or more objects (and / or an environment around the objects) from a sensing signal transmitted from the sensing transmitter. In the sensing receiver, sensing data may be derived from the scattered / reflected signals, and sensing results may be generated / obtained through processing of the sensing data. Here, the sensing results may include characteristic information (e.g., location, distance, speed, angle, etc.) about one or more objects (and / or the environment around the objects). The sensing results generated / obtained in this way may be utilized for wireless sensing services (e.g., detection, tracking, etc. of objects and / or environments) provided in the wireless communication system based on the 6G network of the present specification, or may be provided / disclosed to a trusted third party.

[0198] Additionally, the sensing operation in FIG. 10 is described as a representative example of the operation in a wireless communication system based on a 6G network, but can be extended and applied to cases where terminals / base stations / signals based on networks of previous generations (e.g., 4G, 5G, etc.) are utilized.

[0199] Additionally, with respect to the wireless sensing described herein, in a wireless communication system based on a 6G network of the present specification, time / frequency resources for sensing operations and time / frequency resources for general communications (e.g., UL / DL / sidelink-based communications, etc.) may be scheduled / configured separately.

[0200] FIG. 11 illustrates time / frequency resources for sensing operations according to one embodiment of the present disclosure. The embodiment of FIG. 11 may be combined with various embodiments of the present disclosure.

[0201] Referring to FIG. 11, time / frequency resources (hereinafter, sensing resources) for the aforementioned sensing operation (e.g., sensing operation based on FIG. 10) can be set / allocated separately from time / frequency resources (hereinafter, communication resources) for general communication.

[0202] For example, as illustrated in FIG. 11, sensing resources can be set / allocated in units of symbols in the time domain and / or resource blocks in the frequency domain. Resources other than those for which the sensing resources are set / allocated can be utilized as resources for general communication. That is, sensing resources and communication resources can be set / allocated based on a time-division multiplexing (TDM) scheme and / or a frequency-division multiplexing (FDM) scheme in terms of the operation of the base station / terminal. Additionally or alternatively, unlike what is illustrated in FIG. 10, sensing resources can also be set / allocated based on other units in the time domain (e.g., slots, frames, absolute time (ms, us), etc.) and / or other units in the frequency domain (e.g., subcarriers, carriers, absolute frequencies (MHz, GHz), etc.).

[0203] Additionally or alternatively, in connection with the setting / allocation / scheduling of resources for general communication as described herein, the relationship between the resources and the aforementioned sensing resources may need to be considered. For example, when setting / allocating resources for general communication according to the embodiment(s) of the present disclosure, the resources may be set / allocated to rate-match or puncture the resource region corresponding to the sensing resource. For example, when scheduling resources for general communication according to the embodiment(s) of the present disclosure, the resources may be scheduled so as not to overlap with the resource region corresponding to the sensing resource. If the resources for general communication according to the embodiment(s) of the present disclosure and the resource region corresponding to the sensing resource are set / allocated / scheduled to overlap, one or both operations may be dropped, skipped, or postponed based on priorities, predefined rules, etc. That is, in the embodiment(s) of the present specification, it may be desirable that resources related to general communication (e.g., resources for signals / channels related to UL / DL / Sidelink-based data / control, etc.) are set / allocated / scheduled so as not to overlap with the sensing resources described above.

[0204] Additionally, various channel modeling methods may be applied in connection with the wireless sensing described herein. Channel modeling related to sensing may refer to configuring a path for transmitting and receiving sensing signals and / or scattered / reflected signals, taking into account the object being sensed and / or the environment in which the object resides. Channel modeling may be related to the performance / requirements of sensing in wireless communication systems, and thus may be an important factor in validating the sensing function.

[0205] Channels related to sensing can be divided into channels between objects (e.g., targets of interest) and sensing transmitters / receivers, and channels between the environment to which the object belongs and sensing transmitters / receivers. In this regard, channel modeling related to sensing can be divided based on sensing mode (e.g., the six types of modes described above), whether there is an object / environment, and / or sensing scenarios. For example, channel modeling for a target in a base station / terminal-based monostatic sensing mode, channel modeling for a target in a base station / terminal-based bistatic sensing mode, channel modeling for the environment in a base station / terminal-based monostatic sensing mode, and channel modeling for the environment in a base station / terminal-based bistatic sensing mode can be configured and optimized differently. For example, when various sensing scenarios are classified, channel modeling for detection, location, and tracking scenarios, channel modeling for motion recognition, and channel modeling for imaging / environment reconstruction scenarios can be divided, etc. Additionally, channel modeling related to sensing may be based on statistical channel modeling techniques and / or deterministic channel modeling techniques. For example, modeling for sensing in a wireless communication system based on a 6G network of the present disclosure may be based on stochastic geometric channel modeling techniques and / or hybrid with ray tracing channel modeling techniques. Here, the stochastic geometric channel model may be based on various statistical characteristics of the channel state. Furthermore, the hybrid channel model may be based on both ray tracing techniques and stochastic techniques.In a hybrid approach, channels for objects requiring high accuracy and consistency (e.g., targets of interest) can be modeled using ray tracing techniques, while channels for the environment can be modeled using probabilistic techniques.

[0206] FIG. 12 illustrates a procedure related to a sensing operation according to one embodiment of the present disclosure. The embodiment of FIG. 12 may be combined with various embodiments of the present disclosure.

[0207] For example, in a wireless communication system based on a 6G network of the present specification, in the case of a sensing operation in which a terminal participates, the base station may need to confirm (1205) the capability of the terminal for the sensing operation. In this regard, the terminal may be configured to report capability information on whether it supports the sensing operation to the base station. Additionally or alternatively, if the terminal is defined in advance in the standard as supporting the sensing operation, the procedure may be omitted. In addition, in the case of a sensing operation in which only the base station participates, the base station may be configured to report capability information on whether it supports the sensing operation to an entity that configures / controls its sensing operation (e.g., a network entity at an upper level / layer of the base station).

[0208] For example, the base station can perform signaling with the terminal to exchange configuration information related to the sensing operation. For example, the base station can set / instruct the terminal about the mode of the sensing operation (e.g., based on the six types of modes described above), the subject of the sensing operation (e.g., sensing transmitter, sensing receiver), the resource of the sensing operation (e.g., sensing resource as in FIG. 11), the target of utilizing the sensing result (e.g., type of wireless sensing service based on 6G network, trusted third party), channel modeling for sensing (e.g., channel between the base station / terminal and object / environment), etc. (1210). For example, the base station can also set / instruct such information from a network entity at an upper level / layer of the base station.

[0209] For example, the base station and / or the terminal may perform a sensing operation based on the set / instructed information (1215). For example, the base station and / or the terminal may, as a sensing transmitter and / or a sensing receiver, perform procedures such as transmitting a sensing signal, receiving a scattered / reflected signal, deriving sensing data, obtaining a sensing result through processing the sensing data, and providing the sensing result, as in FIG. 9 described above. As an example, in the operation of the base station / terminal described herein, the sensing result provided through the sensing operation may be utilized.

[0210] < Network Energy Saving, NES >

[0211] Network Energy Saving Technology of Rel-18

[0212] 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 companies. 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. Accordingly, 5G systems are adopting various technologies to reduce energy consumption, known as network energy savings (NES), and the standardization of related technologies will continue.

[0213] Depending on the application of NES technology, the base station can perform operations such as controlling on / off for a certain duration in the time domain, controlling transmission / reception resources for UE-common or UE-specific signals / channels, changing the amount of frequency domain resources, controlling transmission power, or turning on / off antenna ports, transmission-reception points (TRPs), etc. in the spatial domain.

[0214] Figure 13 illustrates an example of the operation procedure of a base station supporting NES technology.

[0215] Referring to Fig. 13, the base station can identify the NES solution(s) to be applied (1305). The 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, etc. The NES solution(s) to be applied may be adaptively selected or predefined based on the current situation (e.g., cell load level, characteristics of connected terminals, etc.). The base station that identified the NES solution(s) can perform signaling for the NES (1310). 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 the 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. Thereafter, the base station performs operations for the NES. At this time, the base station can perform operations for the NES based on the previously performed signaling (1315). That is, based on the system information, configuration information, and control information transmitted through the signaling, the base station can turn on / off the transmission and reception of specific signals, turn on / off elements in the spatial domain, or adjust resources for the transmission and reception of measurement signals.

[0216] Through a procedure similar to that in Fig. 13, NES technology can be implemented. Examples of NES solutions that can be implemented through a procedure similar to that in Fig. 13 are as follows.

[0217] - Intra-system energy saving solution: A RAN node can request a neighboring RAN node to switch at least one SSB beam into its inactive cell, or can perform paging using a limited set of beams to an inactive terminal (e.g., a stationary terminal).

[0218] - Inter-system energy saving solution: NG-RAN nodes that own capacity booster cells can autonomously transition those cells to an inactive state.

[0219] - SSB-less SCell solution: If SSB or SMTC (SSB-based RRM measurement timing configuration) configuration is not provided for the SCell, the UE can obtain timing reference and AGC source from another serving cell. In FR1 or FR2, the base station can configure intra-band CA or inter-band CA including the SCell without SSB transmission, in which case the SSB / SIB transmission can be triggered by the WUS (wake-up signal) of the UE. Accordingly, since the period of common channels / signals such as SSB is increased, the base station can stay in the sleep state for a longer time.

[0220] - Cell DTX / DRX solution: 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) can be commonly set for terminals within a cell having the corresponding feature. Here, the cell DTX pattern and the cell DRX pattern can be set and activated separately, and up to two cell DTX / DRX patterns can be set per MAC entity. When cell DTX is set and activated, at least one of monitoring for SPS opportunities or monitoring PDCCH can be stopped during the cell DTX inactivity period. When cell DRX is set and activated, at least one of transmission on CG resources or SR transmission can be stopped during the cell DRX inactivity period. Cell DTX / DRX can be activated / deactivated via RRC signaling or L1 group common signaling.

[0221] Parameters such as active duration and cycle may be configured for cell DTX / DRX. The active duration is the period during which the UE receives a PDCCH or SPS opportunity and waits to transmit SR or CG, and the cycle specifies 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 are common. If the base station recognizes an emergency call or a public safety-related service (e.g., MPS or 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 is required between the active duration of the connected mode DRX of the UE and the active duration 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.

[0222] - Conditional handover (CHO) solution: A CHO procedure performed in a way that the execution of the handover is determined by the UE is used while the NES technology is applied (e.g., when the cell activates or deactivates cell DTX / DRX). In this case, the UE can use an NES-specific CHO event to initiate CHO for a candidate cell, and the reception of a DCI that activates the CHO condition(s) set by the NES event indication can be applied as an additional triggering condition for this.

[0223] - Spatial and power domain adaptation solution: To support the gNB for transceiver muting and / or transmit power adaptation, the UE may be configured to report multiple CSI entries 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.

[0224] Cell DTX / DRX

[0225] To operate a base station in sleep mode for a relatively long period of time without frequent wake-ups, a base station DTX / DRX has been proposed for NES purposes. The base station can reduce energy consumption by utilizing DTX transmission under low system load conditions by setting a cell DTX and setting the on-duration of the C-DRX of terminals within the active period of the cell DTX. Figure 14 illustrates an example of a procedure for cell DTX / DRX operation.

[0226] Referring to FIG. 14, the base station transmits system information to the terminal (1401), and the terminal checks information related to cell DTX / DRX (1402). For example, the system information may include MIB, SIB1, etc. In relation to NES technology, the MIB may include information related to cell barring (e.g., cellBarred), and the SIB1 may include information related to the cell barring status (e.g., cellBarredNES). Specifically, if cellBarred included in the MIB is set to a value indicating that it is not barred (e.g., notBarred), the terminal may determine that the cell is not barred, regardless of whether it supports NES cell DTX / DRX. Conversely, if cellBarred included in the 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. However, if the terminal has the capability to support NES cell DTX / DRX, the terminal checks SIB1 to determine the cell barring status. If cellBarred of MIB is set to barred and cellBarredNES is absent in SIB1, the terminal supporting NES cell DTX / DRX can treat the cell as barred and perform cell reselection to another cell. On the other hand, if cellBarred of MIB is set to barred and cellBarredNES is included in SIB1, the terminal supporting NES cell DTX / DRX can determine that the cell is not barred.

[0227] In the case of FIG. 14, it is assumed that the terminal has the capability to support NES cell DTX / DRX, and the cellBarred of the MIB is set to notBarred, or the cellBarred of the MIB is barred and cellBarredNES is included in SIB1. Accordingly, the terminal performs a random access procedure to connect to the base station (1403), and can perform communication thereafter. At this time, the base station performs a cell DTX / DRX operation and transmits configuration information related to the cell DTX / DRX operation to the terminal (1404). 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., DCI-related information).

[0228] Thereafter, the base station transmits control information related to cell DTX / DRX to the terminal (1405). The control information related to cell DTX / DRX may include DCI having a designated format (e.g., format 2_9). If an operation for a serving cell according to at least one of the cell DTX operation and the cell DRX operation is configured by configuration information (e.g., cellDTXDRX-Config), the terminal may check a set of search spaces (e.g., a set of Type3-PDCCH CSS) for monitoring a PDCCH conveying control information of a designated format during an active time through a higher layer parameter (e.g., SearchSpace), and may obtain a location of information about the serving cell within the control information through a higher layer parameter (e.g., positionInDCI-cellDTRX). Then, the terminal may obtain control information based on the identified set of search spaces and location.

[0229] 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 an NES-mode indicator, 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 SUL (supplementary uplink) carrier, the indication of activation or deactivation of cell DRX by the cell DTX / DRX indicator may be applied to both the UL carrier and the SUL carrier.

[0230] Thereafter, the terminal and the base station can perform communication based on the cell DTX / DRX (1406). Specifically, the base station can turn on / off the transmission and reception of signals according to the settings related to the cell DTX / DRX, and accordingly, the terminal can selectively monitor the signal from the base station. During the DTX-OFF, the base station enters a sleep mode to reduce energy consumption. At this time, the base station DTX cycle can be aligned with the cycle of the terminal DRX. The base station DTX-ON can completely cover the DRX-ON of the terminal. Furthermore, the base station can align the transmission of Xn / NG and the transmission of Uu for the purpose of NES. The DTX / DRX mechanism triggers the switching of reference signal resource set groups, and the base station can perform a dormancy-like behavior of sparsely transmitting or not transmitting SSB, SIB, and CSI-RS to reduce energy consumption. The terminal can sparsely receive or not receive a downlink signal / channel depending on the settings of the base station. Once the base station DTX / DRX operation is triggered, during the DTX / DRX OFF period, the terminal can discontinuously receive the corresponding CSI-RS, SSB, or PDCCH.

[0231] SSB-less SCell

[0232] Figure 15 illustrates an example of a procedure for CA operation using SSB-less SCell.

[0233] Referring to FIG. 15, the base station transmits configuration information for the SCell to the terminal. That is, the base station transmits configuration information for CA to provide a service to the terminal through CA operation. Here, the CA operation may be intra-band CA or inter-band CA. For example, the configuration information for the SCell may include information related to SCell addition (e.g., sCellToAddModList), 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. Then, the terminal may determine the configuration for the CA operation and perform communication using the PCell and SCell of the base station. At this time, the terminal may confirm that the SCell is an SSB-less SCell based on the information related to the downlink frequency included in the configuration information, and may check the related parameters. For example, a terminal can determine that an SCell is an SSB-less SCell by checking for the presence of a parameter indicating that it is an SSB-less SCell (e.g., SSBlessSCell), and can determine the timing reference and AGC source for the SCell based on information about the reference cell (e.g., referenceCell). In the case of Fig. 15, the reference cell may be a PCell. Therefore, the terminal can use the PCell as a timing reference and AGC source for communication on the SCell.

[0234] Conditional Hand Over (CHO)

[0235] Figure 16 illustrates an example of a Conditional Handover (CHO) procedure. The order of the operations illustrated in Figure 16 may vary depending on the case.

[0236] Referring to FIG. 16, the base station transmits configuration information for CHO to the terminal (1601). The configuration information for CHO may include information related to conditional reconfiguration (e.g., ConditionalReconfiguration, CondReconfigToAddModList) and information related to configuration for reporting (e.g., ReportConfigNR). Here, the information related to configuration for reporting may include information related to events related to reporting, identifiers of the events (e.g., condEventId), information indicating whether it is an NES-specific CHO event (e.g., nesEvent), etc. In the example of FIG. 16, event information indicating that it is an NES-specific CHO event is received.

[0237] The base station transmits information for enabling an NES-specific CHO execution condition to the terminal (1602). 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, for example, as 1-bit information, which indicates enabling the NES-specific CHO execution condition when a related upper layer parameter (e.g., nesEvent) is set and the serving cell of the related block in the corresponding DCI is a primary cell.

[0238] Thereafter, the terminal performs a measurement (1603) and transmits a measurement report to the base station (1604). The base station determines a CHO based on the measurement report and performs signaling for a handover request with the neighboring base stations indicated by the measurement report (1606). The base station determines the neighboring base stations that have confirmed admission through signaling as candidate base stations and transmits information about the candidate base stations to the terminal (1607). Accordingly, the terminal evaluates the CHO execution conditions for the candidate base stations (1608). Accordingly, when a candidate cell satisfying the condition is determined, the terminal detaches from the old cell and synchronizes to the new cell (1609). At this time, since the terminal has previously received event information indicating that it is a NES-specific CHO event and also received information enabling the NES-specific CHO execution condition, it can determine whether the event is satisfied. In other words, if a NES-mode indicator is received through a lower layer and conditional triggering configuration information (e.g., condTriggerConfig) includes information (e.g., nesEvent) indicating that the event is a NES-specific CHO event, 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.

[0239] NES Enhancement

[0240] 3GPP NR release 19 will discuss NES enhancements, with (1) On-demand SSB, (2) On-demand SIB1 transmission, and (3) adaptation of common signal / channel transmissions being considered as key targets.

[0241] (1) On-demand SSB

[0242] A method to reduce energy consumption by having a base station transmit SSB on a specific cell through an on-demand SSB process and not transmit SSB on that cell when an on-demand SSB process is not available can be discussed. In the existing NR system, SSB must be transmitted periodically and constantly for purposes such as time / frequency synchronization or RRM measurement, making it difficult to reduce energy consumption even when the base station has no data to receive or send. Considering this, the base station can reduce base station energy consumption by not performing SSB transmission until the on-demand SSB process is involved and then performing SSB transmission. The on-demand SSB process can be triggered using one of the following methods:

[0243] 1) The terminal requests SSB transmission from the base station by transmitting an uplink signal / channel (e.g., PRACH, PUCCH, PUSCH, SRS in the NR system).

[0244] 2) Requesting SSB transmission from base station (or TRP) #1 to base station (or TRP) #2 through an interface between base stations (e.g., Xn interface in NR system) or backhaul signaling.

[0245] 3) Signaling whether SSB transmission is possible for the corresponding Scell ​​through Scell ​​activation / deactivation signaling.

[0246] Considering coexistence with existing NR terminals, Release 19 is limited to on-demand SSB operation for connected mode terminals and SCells. However, in future releases or next-generation communication systems, on-demand SSB operation (for SSB transmission on PCell) considering inactive or idle mode terminals or initially connected terminals may be defined. In addition, carrier aggregation (CA) including the SCell can be applied to both intra-band CA and inter-band CA, and the SSB on the SCell transmitted through the on-demand SSB process can be utilized for at least functionality such as time / frequency synchronization, L1 / L3 measurement, and SCell activation.

[0247] (2) On-demand SIB1 transmission

[0248] A method to reduce energy consumption by having the base station transmit SIB1 for a specific cell through the on-demand SIB1 process and not transmit SIB1 for the cell when there is no on-demand SIB1 process can be discussed. In the existing NR system, SIB1 containing system information, random access information, etc. for initial access or idle mode terminals to access a cell had to be provided periodically, so it was difficult to reduce energy consumption even when the base station had no data to receive or send. Considering this, the base station can reduce base station energy consumption by not performing SIB1 transmission until the on-demand SIB1 process is accompanied and then performing SIB1 transmission. The on-demand SIB1 process can trigger the base station's SIB1 transmission by the terminal transmitting an uplink signal / channel (e.g., PRACH in the NR system). Specifically, the following scenarios can be considered but may not be limited to the following scenarios.

[0249] 1) Scenario 1: As in (a) of Fig. 17, when a UE receives an SSB (and / or other downlink signal / channel) from a cell#1 and recognizes that SIB1 is not transmitted on the cell#1, the UE can trigger SIB1 transmission by transmitting a signal requesting SIB1 (for convenience, the signal is referred to as a WUS (wake-up signal)) based on information provided in the SSB (and / or other downlink signal / channel) and / or predetermined information. The base station that receives the WUS can transmit a specific DL signal / channel on cell#1 in response thereto, and (or) transmit SIB1 on cell#1 (without transmitting the DL signal / channel).

[0250] 2) Scenario 2: As in (b) of Fig. 17, a terminal may attempt to camp on cell#2 when it receives an SSB (and / or other downlink signal / channel such as SIB1) from a cell#1 and recognizes that SIB1 is not transmitted on the corresponding cell#2. The terminal may trigger SIB1 transmission for cell#2 by transmitting a signal requesting SIB1 (i.e., WUS) on cell#1 based on information provided in the received SSB (and / or other downlink signal / channel such as SIB1) and / or predetermined information. The base station receiving the WUS may transmit a specific DL signal / channel (on cell#1 or cell#2) in response thereto, and may transmit SIB1 for cell#2 on cell#1 or cell#2 (or without transmitting the DL signal / channel).

[0251] 3) Scenario 3: As in (c) of Fig. 17, a terminal that receives an SSB (and / or other downlink signal / channel such as SIB1) from a cell#1 and recognizes that SIB1 is not transmitted on the corresponding cell#2 may attempt to camp on cell#2. The terminal may trigger SIB1 transmission for cell#2 by transmitting a signal requesting SIB1 (i.e., WUS) on cell#2 based on information provided in the received SSB (and / or other downlink signal / channel such as SIB1) and / or predetermined information. The base station that receives the WUS may transmit a specific DL signal / channel (on cell#1 or cell#2) in response thereto, and may transmit SIB1 for cell#2 on cell#1 or cell#2 (or without transmitting the DL signal / channel).

[0252] (3) adaptation of common signal / channel transmissions

[0253] Methods for reducing energy consumption by modulating the transmission of common signals / channels such as SSB, PRACH, and paging by the base station can be discussed. While completely disabling SSB can significantly reduce the energy consumption of the base station, the absence of SSB, which performs functions such as time / frequency synchronization and RRM measurement, may not guarantee stable operation for the corresponding cell from the UE's perspective. Considering this, energy savings at the base station can be achieved by varying the SSB transmission pattern (e.g., transmission period, period per SSB candidate index(es), SSB candidate index(es) transmitted within a transmission period, transmission power, etc.) depending on the situation.

[0254] In the case of PRACH resources, since the base station cannot know when the terminal will transmit the PRACH in the case of contention-based random access, energy consumption may increase because the base station always attempts to receive within the configured PRACH resources. Considering this, energy of the base station can be saved by applying a method to adjust the amount of PRACH resources (e.g., adjusting the period of PRACH resources, adjusting the amount of resources through instructions such as pre-configuring PRACH resource set #1 and set #2 and turning on only one set or both sets, or providing the corresponding RACH resource amount uniformly or non-uniformly for each SSB index).

[0255] In the case of paging, previously, paging frames (PF) and / or paging occasions (PO) were distributed along the time axis within a DRX cycle (or paging cycle), and the terminal attempted to receive paging at a specific PF / PO derived from its ID-based formula. From the base station's perspective, if paging was to be transmitted to multiple terminals simultaneously, it may have to wake up frequently to transmit paging. To reduce base station energy consumption due to this, it is possible to consider arranging PFs and / or POs for paging reception as close to the time axis as possible or arranging different frequency resources within the same time.

[0256] On-demand system information

[0257] Based on the above discussion, this specification discloses a method for on-demand system information (e.g., SI-0, PBCH) usable in next-generation wireless communication systems.

[0258] For communication between a base station and a terminal, the base station can transmit a synchronization signal (SS), and the terminal can obtain time and / or frequency synchronization by receiving the SS. In the 5G NR system, the SS consists of a primary SS (PSS) and a secondary SS (SSS), and the terminal can obtain physical cell ID information through the combination of the PSS and SSS.

[0259] Even in 6G communication standards, an SS may include at least one PSS and / or at least one SSS. For example, information that may be provided / obtained through an SS may include some or all of the following: physical cell ID, TRP ID, and beam index information.

[0260] Before describing the proposed new SS transmission structure, we first briefly describe SS in the existing 5G system. In a 5G NR system, the PBCH is transmitted across 4 OFDM symbols along with the PSS / SSS, and the corresponding block is called an SSB (SS / PBCH block). The PBCH can include timing information such as the system frame number (SFN), half frame indicator, and SSB index; PRB grid information such as the sub-carrier offset; sub-carrier spacing / CORESET / Type0-PDCCH CSS set information for PDCCH reception that schedules the SIB1 PDSCH; DMRS type A position information; cell barring information; and CRC. The UE can obtain time / frequency synchronization and physical cell ID-related information through the PSS / SSS, and additional timing information and information necessary for SIB1 reception through the PBCH. Based on this information, the UE can receive SIB1, obtain DL / UL BWP and random access procedure-related information, attach to the corresponding cell, and initiate communication.

[0261] Table 1 is part of the 5G NR standard document TS 38.213 Rel.18.

[0262]

[0263]

[0264]

[0265]

[0266] As shown in Table 1, the 5G NR standard defines the location of SSB by classifying cases according to sub-carrier spacing (SCS). In addition, depending on the frequency range (FR) and / or frequency band and / or whether it is paired spectrum (e.g., FDD) or unpaired spectrum (e.g., TDD) and / or whether shared spectrum channel access is applied or not (e.g., unlicensed band or licensed band), L max (This refers to the maximum SSB index or number of SSB beams, and is denoted as L_max for convenience below) and N max (This refers to the maximum number of candidate SSB indices, and is denoted as N_max for convenience below) The value is defined differently.

[0267] For example, for FR2, the L_max value is 64. For FR1 and 15 kHz SSB, the L_max value is 4 in the band below 3 GHz and 8 in the band above 3 GHz. For FR1 and 30 kHz SSB, 1) for FDD, the L_max value is 4 in the band below 3 GHz and 8 in the band above 3 GHz, and 2) for TDD, the L_max value is 4 in the band below 1.88 GHz and 8 in the band above 1.88 GHz.

[0268] For Case A / C in Table 1 above, it is stated that the symbol index starts from the half frame boundary, and the SSB is located from the symbol index of {2,8}+14n.

[0269] As an example, Fig. 18 illustrates Case A / C SSB pattern when L_max=8. Referring to Fig. 18, one slot consists of 14 symbols, and 0 / 1 / 2 / 3 / 4 / 5 / 6 / 7 / 8 / 9 / A / B / C / D represent symbol index 0 / 1 / 2 / 3 / 4 / 5 / 6 / 7 / 8 / 9 / 10 / 11 / 12 / 13, respectively. In addition, P represents PSS, and S represents time / frequency domain in which SSS is transmitted (i.e., PSS / SSS are 1 symbol / 12 PRBs each). In addition, the symbol following PSS, the frequency domains above / below the symbol including SSS, and the channel transmitted in the symbol following SSS represent PBCH, and the numbers 1 to 8 written in the PBCH represent SSB indexes.

[0270] Meanwhile, in Fig. 18, each grid at different left / right positions in the time domain may equally mean 1 symbol, but each grid at different upper / lower positions in the frequency domain may not mean a frequency resource unit of the same size. For example, when 1 SSB is composed of a total of 240 subcarriers (e.g., 20 RBs), the grid to which the PSS( / SSS) is mapped (and grids at the same frequency position as the corresponding grid) may include 127 subcarriers, but the grid immediately below or above the grid to which the PSS( / SSS) is mapped (and grids at the same frequency position as the corresponding grid) may include 56 or 57 subcarriers. In addition, for convenience, the PBCH channel and the PBCH DMRS are not separately illustrated in Fig. 18.

[0271] In this way, in the time domain direction, the grids represent the same time resources (e.g., symbols), but in the frequency domain direction, different upper / lower position grids can represent sets of frequency resources (e.g., subcarrier sets or RB sets) with different numbers of elements, and this can be applied not only to FIG. 18 but also to the SSB transmission example drawings described below.

[0272] 6G systems may also introduce initial access through at least some similar processes. For example, after SS is transmitted, a signal / channel similar to the PBCH of 5G NR (referred to as SI-0 in this specification for convenience and may be replaced with PBCH) may be transmitted, which may include all / part of the information carried in the PBCH of 5G NR, and thereafter, a signal / channel similar to the SIB1 of 5G NR (referred to as SI-1 for convenience) may be transmitted, which may include all / part of the information carried in the SIB1 of 5G NR.

[0273] For example, SI-0 (system information-0) may include essential system information that a terminal that has received SS must receive for the first time to access the corresponding cell, and SI-0 may include a master information block (MIB). As described below, SI-0 may be transmitted on-demand in at least some cells, and at least some of the information necessary for receiving SI-0 (e.g., UL WUS-related information described below) may be included in SS (and / or system information received from other cells). After receiving SI-0, the terminal needs to receive other system information, and the system information received after SI-0 will be referred to as SI-1. SI-1 may include, for example, SIB1 (system information block 1). At least some of the information necessary for receiving SI-1 may be included in SI-0 (and / or SS).

[0274] In the prior art / contribution / standard, the terms SSB burst / block and SS burst / block have been used interchangeably to refer to the SS+PBCH block structure. Therefore, the terms SSB burst / block and SS burst / block have been understood to have virtually the same meaning, and both assume that the PBCH is included in the corresponding burst / block. However, in some embodiments of the present specification, the terms SS burst / block or SSB / SSB burst may mean SS excluding SI-0 (e.g., PSS / SSS), in which case, SI-0 burst / block may mean SI-0 (excluding SS) structure. Meanwhile, an SI-0 block included in an SI-0 burst may be simply referred to as SI-0.

[0275] In this disclosure, we consider a scenario where SI-0 may not always be transmitted to save energy at the base station. By receiving an SS, the terminal can recognize that SI-0 is not transmitted periodically in the corresponding cell (e.g., resources may be configured periodically / aperiodicly, but SI-0 may not be provided in an always-on form) and that UL WUS (uplink wake-up signal) transmission is required to trigger SI-0 transmission by the base station. For this purpose, the SS may include all or part of the following information (for convenience, the following information is referred to as “SS-information”) (via a separate signal / channel that is FDM (and / or TDM) with the SSS (and / or PSS) or by utilizing a PSS / SSS sequence).

[0276] - Index of each SS block: The SS block index may be required for the purpose of allowing the terminal to obtain a frame boundary, obtain a QCL relationship between the SS block index and the SI-0 index, determine the resource of the UL WUS signal / channel corresponding to the SS block index, or find the location of the SI-0 index from a specific SS block index.

[0277] - Which number (within an SS burst) the SS block is transmitted or which SI-0 index (QCL) it has: For example, if SS block index 2 is actually the first SS block that the base station is transmitting in the SS burst, the base station can signal that SS block index 2 is the first transmitted SS block. A terminal receiving the signaling can recognize that SI-0 associated with SS block index 2 (e.g., in QCL) is SI-0 index 1. Alternatively, the base station can signal the SI-0 index linked to the SS block index. For example, a terminal that is signaled that SS block index n has a value of m can recognize that the SI-0 index linked to SS block index n is m.

[0278] - SI-0-burst position information: When the position of SI-0-burst can be determined relatively from the position of SS-burst or absolutely by utilizing frame boundary, etc., the necessary parameters can be signaled.

[0279] - Information about resources of UL WUS (e.g., PRACH): Some or all information that sets up the resources of the corresponding signal / channel may be signaled.

[0280] - Information about the transmission of SI-0-burst: (In case of on-demand procedure based operation) whether SI-0-burst is transmitting or not can be signaled. If the UE receives signaling that it is not transmitting, it can expect to receive SI-0 by transmitting a signal / channel for SI-0-burst request, and if it receives signaling that it is transmitting, it can expect to receive SI-0 at the defined / signaled SI-0-burst position. Alternatively, if the UE receives signaling that it is not transmitting, it can not expect to receive SI-0 at the SI-0-burst position (additionally it can attempt detection / (re)selection of other cells), and if it receives signaling that it is transmitting, it can expect to receive SI-0 at the defined / signaled SI-0-burst position. In case of on-demand procedure based operation, it can be predefined or signaled how long (and how frequently) SI-0 is transmitted after an SI-0-burst request. After transmitting a signal / channel for requesting an SI-0-burst, the terminal can expect that the base station will transmit an SI-0 during the corresponding time interval (with the corresponding period) starting from a predetermined time. Information about the transmission pattern (e.g., periodicity, offset, etc.) of the currently transmitting SI-0-burst can be signaled. For example, in case of an operation based on SI-0-burst periodicity adaptation, how large (or small) the SI-0-burst period is compared to the SS-burst period, or what the period (and / or offset) value is, can be signaled.

[0281] - Power offset between SS-burst and SI-0-burst: The power offset value can be predefined or explicitly signaled through the SS-burst. In addition, the power offset between the PSS, SSS, and "a separate signal / channel that is FDM (and / or TDM) with the SSS (and / or PSS)" that constitute the SS-burst can be predefined. The power offset here can mean EPRE (energy per resource element).

[0282] Hereinafter, WUS transmission examples [WUS Example #y] will be described first to help understand [Proposal #x] described later. Depending on the implementation, [WUS Examples #y] may be used for [Proposal #x], but the implementation of [Proposal #x] is not necessarily construed as presupposing the application of [WUS Example #y]. In addition, in the description below, the distinction of [WUS Example #y] and / or the distinction of [Proposal #x] and the indices x and y assigned to each are only for the convenience of explanation and do not necessarily mean that each index is implemented in an independent form. Depending on the implementation, at least some of them may be implemented in a combined form or each may be implemented individually.

[0283] Meanwhile, the terminal may be configured for UL WUS resources to request SI-0, for example, based on at least some of the following methods:

[0284] [WUS Example #1] Frequency Resource Configuration for UL WUS

[0285] In a situation where only SS is received by the terminal, the frequency resource information of the corresponding cell (e.g., cell / carrier BW or BW of initial BWP) may not be accurately identified from the terminal's perspective. Therefore, it may be desirable to set the frequency resource of UL WUS (e.g., WO: WUS occasion) based on the frequency location of the SS. WO (WUS occasion) may refer to time / frequency resources available for UL WUS transmission. For example, if UL WUS is a random access channel / preamble, WO may be RO (random access occasion).

[0286] For example, the relative frequency position between the lowest sub-carrier index (or highest sub-carrier index or center frequency) of the SS and the WO can be defined. Specifically, the lowest sub-carrier index (or highest sub-carrier index or center frequency) of the SS and the lowest sub-carrier index (or highest sub-carrier index or center frequency) of the WO can be the same. As another example, the link relationship between the lowest sub-carrier index (or highest sub-carrier index or center frequency) of the SS and the lowest sub-carrier index (or highest sub-carrier index or center frequency) of the WO can be defined in advance, and if there is more than one lowest sub-carrier index (or highest sub-carrier index or center frequency) of the WO linked to the lowest sub-carrier index (or highest sub-carrier index or center frequency) of one SS, the base station can explicitly set / indicate one of the values, or implicitly determine it (e.g., based on the physical cell index, TRP index, or UE index).

[0287] Alternatively, an offset value between the lowest sub-carrier index (or highest sub-carrier index or center frequency) of the SS and the WO can be defined / set. The granularity of the offset value can be in units of sub-carriers, or in units of groups of sub-carriers (e.g., PRB with 12 sub-carriers as a group). Here, the size of the sub-carrier can be the sub-carrier size applied to the SS (or SI-0 or SI-1 or UL WUS) or a predefined sub-carrier size. As a specific example, if the offset value is defined / set as K sub-carriers, it can mean that the lowest sub-carrier index (or highest sub-carrier index or center frequency) of the WO is shifted (upward or downward) by K sub-carriers from the lowest sub-carrier index (or highest sub-carrier index or center frequency) of the SS.

[0288] For example, WO can be set / indicated based on the reference frequency position F_base. For example, F_base can be determined / indicated based on SS. As a specific example, F_base can be the lowest sub-carrier index (or highest sub-carrier index or center frequency) of SS, or a reference frequency position provided based on SS information, or a predefined frequency position (e.g., the lowest sub-carrier of Common RB 0).

[0289] For example, the relative frequency position between F_base and WO can be defined. Specifically, the lowest sub-carrier index (or highest sub-carrier index or center frequency) of F_base and WO can be the same. Alternatively, a (frequency) offset value between F_base and WO can be defined / set. The granularity of the offset value can be in units of sub-carriers, or in units of groups of sub-carriers (e.g., PRBs that group 12 sub-carriers). Here, the size of the sub-carrier can be the sub-carrier size applied to SS (or SI-0 or SI-1 or UL WUS) or a predefined sub-carrier size. As a concrete example, if the offset value is defined / set as N PRB (where PRB is a group of 12 sub-carriers), it can mean that the lowest sub-carrier index (or highest sub-carrier index or center frequency) of WO is shifted (upward or downward) by N PRB from F_base.

[0290] In this example, the frequency-axis BW occupied by the WO may be a predefined or set / indicated value. For example, if the UL WUS sequence length is 139, the BW corresponding to the minimum PRB number greater than that, 12 PRBs, may be defined as the BW of the WO.

[0291] Furthermore, this method may be suitable for TDD bands where the DL spectrum and UL spectrum are unpaired. In FDD bands where the DL spectrum and UL spectrum are paired, this method may be applied based on a specific subcarrier of the UL spectrum linked to the DL spectrum where the SS is received. The subcarrier may be a predefined or set / indicated value.

[0292] For example, the relative frequency location between a specific sub-carrier of the UL spectrum and a WO can be defined. Specifically, a specific sub-carrier of the UL spectrum and the lowest sub-carrier index (or highest sub-carrier index or center frequency) of the WO can be the same. As another example, a link relationship between the lowest sub-carrier index (or highest sub-carrier index or center frequency) of an SS and the lowest sub-carrier index (or highest sub-carrier index or center frequency) of a WO (within the UL spectrum) can be defined in advance, and if there is more than one lowest sub-carrier index (or highest sub-carrier index or center frequency) of a WO (within the UL spectrum) linked to the lowest sub-carrier index (or highest sub-carrier index or center frequency) of an SS, the base station can explicitly set / indicate one of the values, or implicitly determine it (e.g., based on a physical cell index, a TRP index, or a UE index).

[0293] Alternatively, an offset value between a specific sub-carrier of the UL spectrum and the WO can be defined / set. The granularity of the offset value can be in units of sub-carriers, or in units of groups of sub-carriers (e.g., PRBs with 12 sub-carriers as a group). Here, the size of the sub-carrier can be the sub-carrier size applied to the SS (or SI-0 or SI-1 or UL WUS) or a predefined sub-carrier size. As a specific example, if the offset value is defined / set as K sub-carriers, it can mean that the lowest sub-carrier index (or highest sub-carrier index or center frequency) of the WO is shifted (upward or downward) by K sub-carriers from a specific sub-carrier of the UL spectrum.

[0294] The number of frequency axis WOs can be fixed to one, or defined or set to one or more values. If multiple FDMed WOs are defined / set, the frequency axis spacing between the WOs can also be defined or set.

[0295] If, as described above, the UL WUS or WO frequency resources are confined within the SS band or determined based on the frequency location of the SS, the base station may perform transmission and reception only on band #A, where SS and WO are transmitted and received, and then, when receiving the UL WUS transmitted by the terminal, the base station may need to perform transmission and reception on band #B to transmit SI-0. For example, if band #A, where transmission and reception are performed before SI-0 transmission, and band #B, where SI-0 transmission is performed, are different (or band #B is larger than band #A), a processing delay similar to the BWP switching delay may be required from the base station's perspective. Therefore, the minimum gap between the time points at which the terminal expects SI-0 reception after the UL WUS transmission may be defined separately (e.g., it may be defined as a value larger than the minimum gap between the time points at which the terminal expects RAR reception after the PRACH transmission in a 5G NR system), or the base station may set the size of the gap.

[0296] The base station can receive an UL WUS for requesting SI-0 transmitted by a terminal in the frequency resources of the WO set or defined as above. If the base station successfully receives the UL WUS, it can initiate a response to the UL WUS and / or SI-0 transmission.

[0297] [WUS Example #2] Setting up UL WUS time resources

[0298] When considering an SS structure associated with one or more beam indices, each WO can also be associated with one or more beam indices. Here, the association of a WO with a specific beam index (or SS index) may mean that the WO and the SS having the corresponding beam index (or SS index) are associated. For convenience, in this specification, a group of WOs that includes at least one WO associated with all SS indices that can be transmitted (or are being transmitted) in the corresponding cell is called a WO burst. For example, if a maximum of L_max SS indices can be transmitted in the corresponding cell or L_act (<= L_max) SSB indices are (actually) being transmitted, the WOs associated with SS indices L_max or L_act can be defined as one WO burst. For example, the L_max value can be defined in advance (e.g., different L_max values ​​are defined in the standard depending on the frequency band), and the L_act value can be signaled via SI-0 (or SI-1).

[0299] The position of a WO burst can be determined (the starting position of a WO burst) by the parameters {WO periodicity, WO offset}, and the position of each WO within one WO burst can be determined by the parameters {# of WOs, WO length / interval}.

[0300] WO periodicity can be predefined (e.g., 160 msec), determined as a relative value of SS periodicity (e.g., determined as n times SS periodicity, where n can be a predefined or set value, and SS periodicity can be a predefined or set value), or explicitly set.

[0301] The WO offset (e.g., time resource offset) can be predefined (e.g., 10 msec), determined as a relative value from the SS (e.g., determined as a location X msec away from SS index#0, where X can be a predefined or set value), explicitly set (e.g., one of Y candidates for the WO offset value is set), or implicitly determined (e.g., one of Y candidates for the WO offset value is derived based on the cell / TRP index). The WO offset value can be a value applied based on a specific SFN index (SFN=0). For example, when WO periodicity is determined to be 160 msec and there are a total of 4 candidates with WO offset values ​​of 10 / 50 / 90 / 130 msec, if the value obtained by taking modulo 4 of the physical cell index acquired by the terminal through SS is 3, the terminal can recognize that a periodic WO burst is located at a cycle of 160 msec from 130 msec based on SFN=0.

[0302] The "# of WOs" value can be determined by the SS-to-WO mapping ratio. If the SS-to-WO mapping ratio is 1, it means that one SS index is linked to one WO. If the SS-to-WO mapping ratio is greater than 1 (e.g., if N), it means that N SS indices are linked to one WO (or the same SS index is linked to N WOs). If the SS-to-WO mapping ratio is less than 1 (e.g., if 1 / N), it can mean that the same SS index is linked to N WOs (or N SS indices are linked to one WO). The SS-to-WO mapping ratio can be defined or set to a specific value (e.g., 1) in advance. In this case, the "# of WOs" value can be defined as the maximum number of WOs for which all SS indices of L_max or L_act can be linked at least K times (e.g., K can be defined or set to a specific value, for example, 1, in advance). If "# of WOs" is determined based on L_max and N=K=1, the "# of WOs" that constitute one WO burst can be L_max.

[0303] The WO length / interval parameter can be a parameter that determines the time-domain duration (which may include CP and guard time) that a WO spans and / or the interval between WOs (or WO groups). If the time-domain duration that a WO occupies can be Z OFDM symbols (from S OFDM symbols), the corresponding S and / or Z values ​​can be predefined (e.g., 12 or the maximum number of OFDM symbols supported by the specification for PRACH) or settable values. The WO interval can also be set / applied for each WO (group), and the corresponding interval value can be a symbol-level value or a slot-level value. If multiple WOs are included in a WO group, the WOs can be arranged consecutively without an interval between the WOs. For example, if the WO duration is 4 symbols, 3 WOs form a WO group, and the interval between WO groups is 2 slots, 3 WOs can be arranged consecutively in the starting slot n of a WO burst, and 3 WOs can be arranged consecutively again in slot n+2. The number of WOs belonging to a WO group and / or the interval value between WO groups can be defined or set in advance.

[0304] Figure 19 shows an example of an SS( / SI-0) burst and a WO burst.

[0305] As shown in the above Fig. 19, the period of SS / SI-0 (e.g., SS periodicity is T1-T0) and the period of WO burst (e.g., WO periodicity is T3-T2) can be defined / set differently. If the reference point of WO (time) offset such as SFN index=0 is T0, T2-T0 can mean WO offset. When L beam indices are transmitted within one SS+SI-0 burst, WOs corresponding to N SS / beam indices can be transmitted within the WO burst, and if the SS-to-WO mapping ratio is 1, N can be L. In addition, the interval between WO (groups) within the WO burst can also be defined / set through the above methods.

[0306] The base station can receive an UL WUS for requesting SI-0 transmitted by a terminal within the time resources of the WO set or defined as described above. If the base station successfully receives the UL WUS, it can initiate a response to the UL WUS and / or SI-0 transmission.

[0307] [WUS Example #3] UL WUS Sequence Resource Setting and Power Control

[0308] The number of UL WUS sequences (=N_WUS) corresponding to one SS index can be predefined or set. Considering that any terminal requests SI-0 and the base station that receives the SI-0 transmits SI-0, it may be desirable to define the number of UL WUS sequences corresponding to one SS index as 1. However, if the contention resolution function between terminals is considered in addition to the SI-0 request function, it may be advantageous to have multiple UL WUS sequences corresponding to one SS index. Therefore, the N_WUS value can be predefined or set to a specific value (e.g., N_WUS=1). For example, if two SS indexes are linked to one WO and the N_WUS value is 1, two UL WUS sequences should be provided to the WO. As another example, if one SS index is linked to one WO and the N_WUS value is 4, four UL WUS sequences should be provided to the WO.

[0309] Information about the UL WUS sequences that constitute each WO (e.g., root sequence index, cyclic shift index, etc.) can be defined or set in advance. For example, a rule can be applied that derives the starting index of the root sequence index based on the cell / TRP index, applies the derived root sequence index to the first WO, and applies the next index (or the same index) to the second WO. If multiple UL WUS sequences exist in one WO, the cyclic shift value can be applied by dividing the maximum cyclic shift number by N_WUS. For example, if the UL WUS sequence length is determined to be 139, the maximum cyclic shift number can be 139, and if N_WUS is 4, when the result obtained through the floor(139 / 4) (or ceiling(139 / 4)) operation is defined as CS_unit, each sequence can be determined such that the cyclic shift values ​​of the four UL WUS sequences differ by CS_unit.

[0310] In the random access procedure of the existing 5G NR system, the terminal can measure the path loss using the SSB power value of the base station and the power value of the actual SSB reception, and set the PRACH initial power value based on the measured value. In addition, if a RACH failure occurs due to a reception failure such as msg2 / 4 after the PRACH transmission, the number of PRACH retransmissions and / or the power ramping counter value is increased, and the PRACH transmission power value is increased by the power step value. For UL WUS transmission, the SS power value and / or power step value can be set similarly to the existing method, or some / all parameter values ​​can be defined in advance to minimize the configuration information. For example, if the SS power value is defined as a specific value, the terminal can perform path loss estimation by assuming that the SS is transmitted from the base station with the corresponding power value without separate information. As another example, if the power step value is defined as a specific value and SI-0 is not received after UL WUS, the power ramping counter value can be increased and the power can be increased (or maintained) by the power step value to attempt UL WUS retransmission.

[0311] The base station can receive a UL WUS for requesting SI-0 transmitted by a terminal from the UL WUS sequence resources set or defined as above. If the base station successfully receives the UL WUS, it can initiate a response to the UL WUS and / or SI-0 transmission.

[0312] [WUS Example #4] Specific UL WUS Resource Signaling

[0313] In determining UL WUS resources through at least some of the above examples, at least some / all of the following parameters may be set by the base station.

[0314] - The lowest sub-carrier index (or highest sub-carrier index or center frequency) of the WO linked to the lowest sub-carrier index (or highest sub-carrier index or center frequency) of the SS.

[0315] - SS's lowest sub-carrier index (or highest sub-carrier index or center frequency) or offset value between F_base and WO

[0316] - Frequency axis BW occupied by WO (or sequence length of WO)

[0317] - (For FDD) A specific sub-carrier of the UL spectrum linked to the DL spectrum that received SS / SI-0.

[0318] - (For FDD) Offset value between a specific sub-carrier of the UL spectrum and the WO

[0319] - Number of WOs in the frequency axis and / or frequency spacing between WOs (if multiple FDMed WOs are defined / set up)

[0320] - The multiplier relationship between WO periodicity or WO periodicity and SS periodicity

[0321] - WO offset or offset from the position of a specific SS index

[0322] - SS-to-WO mapping ratio and / or L_max and / or L_act

[0323] - Duration of the time axis occupied by WO

[0324] - WO interval related parameters

[0325] - Number of UL WUS sequences corresponding to one SS index (=N_WUS)

[0326] - Information about the UL WUS sequence that constitutes each WO (e.g., root sequence index, cyclic shift index, etc.)

[0327] - SS power value and / or power step value and / or maximum WUS retransmission counter value and / or maximum power ramping counter

[0328] Some / all of the above parameters may be defined as specific values ​​in the standard. Alternatively, the standard may define several candidate values ​​for some / all of the above parameters, and one of the values ​​may be determined based on the cell / TRP / UE index (e.g., modulo operation, etc.).

[0329] Alternatively, several candidate values ​​may be defined in the standard for some / all of the above parameters, and one of the values ​​may be signaled by SS (via a separate signal / channel that is the SSS (and / or PSS) and FDM (and / or TDM) or by utilizing the PSS / SSS sequence). In this case, when a specific value is signaled, the corresponding value for each individual parameter may be individually signaled or may be jointly coded and signaled. As an example of joint coding, some / all of the above parameters may be grouped together to form a single combination, and multiple such combinations may be indexed / tabled and defined in the standard, and a single combination may be set through SS. For example, if {the time axis duration occupied by WO, the number of UL WUS sequences corresponding to one SS index} are grouped and index 0 = {12 symbols, N_WUS=1}, index 1 = {4 symbols, N_WUS=2} is defined in the standard, then setting index 0 can signal that the time occupied by WO is 12 symbols and the number of UL WUS sequences corresponding to one SS index is 1. As another example, some / all of the above parameters can be divided into multiple groups (for example, the 1st / 2nd / 3rd parameters can be group 1, the 4th / 5th / 6th / 7th parameters can be group 2), and multiple combinations for each group can be indexed / tabulated and defined in the standard, and one combination can be set for each group through SS.

[0330] The base station can set information about UL WUS resources as described above. Through the set resources, the terminal transmits UL WUS, the base station transmits SI-0, and the terminal receives SI-0, thereby attaching to the corresponding cell and starting communication. In this way, a series of processes in which SS is always transmitted but SI-0-burst is transmitted only when there is a request from the terminal (e.g., through UL WUS) are conveniently named on-demand SI-0 procedure. Therefore, the present disclosure proposes a method for specifically setting UL WUS resources for requesting SI-0, a method for transmitting UL WUS, a method for receiving the requested SI-0, and a method for measuring SS blocks. The UL WUS may be, for example, a Zadoff chu sequence (such as PRACH).

[0331] [Proposal #1] UL WUS Resource Setting

[0332] As suggested in [WUS Example #1] to [WUS Example #4], the terminal can obtain UL WUS configuration information for requesting SI-0 while receiving SS of a specific cell. For example, in [WUS Example #1], the frequency resource of UL WUS can be determined based on SS resource. In addition, the values ​​of most of the parameters required for UL WUS configuration listed in [WUS Example #4] are defined in the standard, and only the minimum parameters can be signaled by SS (or via a separate signal / channel that is SSS (and / or PSS) and FDM (and / or TDM), or by utilizing PSS / SSS sequence). In addition, all or part of the SS information can be signaled by SS (or via a separate signal / channel that is SSS (and / or PSS) and FDM (and / or TDM), or by utilizing PSS / SSS sequence). Alternatively, all or part of the parameters required for UL WUS configuration listed in [WUS Example #4], or all or part of the SS information, may be provided to the terminal from the base station in another serving cell / carrier / BWP / non-serving cell / neighbor cell, etc., where the SS is not transmitted.

[0333] When operating this on-demand SI-0 procedure, energy savings at the base station can be maximized by individually configuring the SS-burst and SI-0-burst that constitute the SSB burst. Specifically, the following exemplary methods may be considered.

[0334] [SS-burst Example #1] Individually operate SS-burst consisting of PSS / SSS, etc. and SI-0-burst consisting of SI-0.

[0335] In this example, SS burst / block can mean SS (excluding SI-0), and SI-0 burst / block can mean SI-0 (excluding SS) structure.

[0336] In this way, we propose a method to reduce the energy consumption of a base station for transmitting an SSB burst by separately operating an SS-burst composed of PSS / SSS, etc., and an SI-0-burst composed of SI-0. The sequence of PSS / SSS / SI-0 DM-RS, the configuration of SI-0 payload, the time axis position of PSS / SSS / SI-0, and / or the size of frequency resources occupied by PSS / SSS / SI-0 may differ from those defined in the existing 5G NR standard.

[0337] If the existing NR's SSB burst structure (e.g., FIG. 18) is borrowed, PSS / SSS and SI-0 (corresponding to the PBCH of FIG. 18 in the existing NR) are TDM / FDM within one SSB, so even if it is an SI-0-less SSB burst, only a few symbol gaps are created between SS-bursts. Since it is difficult for the base station to transition to a sleep state with only this symbol gap, it may be efficient to operate the SS-burst and SI-0-burst separately, thereby transmitting only the SS-burst and allowing the base station to operate in energy saving mode.

[0338] Figure 20 illustrates an example of separately operating SS-burst and SI-0-burst based on SS-burst example #1.

[0339] Referring to FIG. 20, a structure can be introduced in which an SS block corresponding to one beam or SS index is composed of a total of two OFDM symbols. In FIG. 20, for convenience, it is assumed that one SS block is composed of one PSS and one SSS, but the present invention is not limited thereto, and one SS block can be composed of at least one PSS, at least one SSS, or at least one PSS and at least one SSS. By positioning four SS block indices within one slot, the number of slots spanned by L_max SS blocks on the time axis can be reduced. Compared to the SSB burst configuration of the existing NR (e.g., FIG. 18), in the existing NR, the time taken by the base station to transmit L_max SSBs was 4 msec per SSB period, but in FIG. 20, by reducing it to 2 msec or less in L_max SS blocks (SS blocks constituting an SS burst), the energy consumption of the base station can be reduced. Additionally, by leaving some symbols for each slot empty (e.g., symbols between SS blocks #2 and #3 and / or start / end symbols within a slot), there is an advantage in that DL control / data signals / channels or UL control / data signals / channels can be transmitted through those symbols.

[0340] In Fig. 20, a slot structure consisting of 14 symbols is assumed and a structure of 2 empty symbols - 2 SS blocks - 2 empty symbols - 2 SS blocks - 2 empty symbols is considered, but any 6 symbols within the 14 symbols can be configured as empty symbols, more than 4 2-symbol SS blocks can be located within one slot, and it can be extended to a slot structure consisting of a number of symbols different from 14 symbols. In addition, by providing a symbol gap between the PSS and the SSS, a performance improvement effect can be obtained when using the PSS / SSS for carrier frequency offset (CFO). As an example of forming a symbol gap between the PSS and the SSS, the PSS can be located at symbols 2 / 3 / 8 / 9, and the SSS corresponding to symbols 4 / 5 / 10 / 11 can be located, respectively. When forming a symbol gap between PSS and SSS, the SS block may be composed of PSS(s) or may be composed of SSS(s), and a PSS block and an SSS block may form a pair and be linked to (at least) one SI-0 block.

[0341] In Fig. 20, the SI-0 burst can be transmitted separately from the SS burst (on-demand), and for convenience, it is assumed that the SI-0 burst contains 8 SI-0 blocks.

[0342] There is a trade-off relationship between the energy saving effect of the base station and the multiplexing efficiency. Considering this, a method of pre-configuring N_max candidate SS blocks, which is more than L_max, and limiting the transmission of up to L_max SS blocks can be applied to the corresponding SSB burst structure. Specifically, as shown in Fig. 21, an SS-burst can be configured without a symbol gap between SS blocks, and a total of N_max (14 in the example) candidate SS blocks can be allowed. In this state, the base station can select up to L_max SS blocks among the N_max candidate SS blocks for transmission. For example, if SS block indexes 1 / 2 / 3 / 4 / 5 / 6 / 7 / 8 are selected, the base station energy saving effect can be obtained, and if SS block indexes 2 / 3 / 5 / 6 / 9 / 10 / 12 / 13 are selected, the multiplexing efficiency can be improved.

[0343] Although Fig. 21 assumes a slot structure consisting of 14 symbols, it can be extended to slot structures consisting of a different number of symbols than 14. Furthermore, although the starting position of the SS burst is proposed as the first symbol of slot n, it can also be extended to a method starting from any arbitrary symbol.

[0344] Even if the SS blocks constituting the SS-burst exist up to N_max indices, the SI-0 index constituting the corresponding SI-0-burst can be limited to L_max. This is because only up to L_max SS blocks are transmitted, so the SI-0 constituting the SI-0-burst can also operate even if only up to L_max numbers exist. In Fig. 21, the SI-0 burst can be transmitted separately from the SS burst (on-demand), and for convenience, it is assumed that L_max is 8, that is, the SI-0 burst includes 8 SI-0 blocks.

[0345] In a method such as FIG. 20 or FIG. 21, a performance improvement effect can be obtained when using carrier frequency offset (CFO) using SI-0 DM-RS by providing a symbol / slot gap within the time domain constituting one SI-0 index. For example, SI-0 index k can be positioned at symbol n / n+2, and SI-0 index k+1 can be positioned at symbol n+1 / n+3. In addition, a symbol / slot gap can be applied between SI-0 indices. In order to match the number of RBs allocated for SI-0 to a level similar to SI-0 of FIG. 18, the total number of RBs of SI-0-burst can be increased to 20 or more.

[0346] Conversely, instead of reducing the number of RBs allocated for SI-0 (e.g., reducing the total number of RBs in an SI-0 burst to less than 20), an approach could be used to increase the number of symbols spanned by an SI-0 burst (or the number of symbols per SI-0 block).

[0347] As in WUS Example #2, it may be necessary to associate between WO and SS block index (or beam index). However, when SS-burst is configured in the same way as in FIG. 21, that is, when there are N_max SS block indexes greater than L_max, there is an issue of whether SS-to-WO mapping should be performed based on Alt-1) L_max or Alt-2) N_max. Here, the SS-to-WO mapping based on L_max may mean that when there are multiple WO resources determined by the WUS examples, each WO is mapped from SI-0 index 0 (not SS index) to SI-0 index {L_max - 1}, and the "# of WOs" value may mean the maximum number of WOs for which all L_max SI-0 indices can be associated at least K times (e.g., K may be predefined or set to a specific value, for example, 1). In addition, the fact that the SS-to-WO mapping is based on N_max means that when there are multiple WO resources determined by the above WUS examples, each WO is mapped from SS index 0 to SS index {N_max - 1}, and the "# of WOs" value may mean the maximum number of WOs that can be linked at least K times (e.g., K may be defined or set in advance to a specific value, for example, 1) for all N_max number of SS indices.

[0348] In the case where SS-to-WO mapping is determined based on L_max, such as Alt-1, the terminal may select a WO linked to SS index n based on SI-0 index m linked to SS index n, rather than SS index, when selecting the WO. At this time, SI-0 index m linked to SS index n can be notified to the terminal through SS (via a separate signal / channel that is SSS (and / or PSS) and FDM (and / or TDM) or by utilizing PSS / SSS sequence). For example, a terminal that receives SS index 3 can also receive information that SS index 3 and SI-0 index 2 are linked through the SS block. A terminal that determines that the reception sensitivity of SS index 3 is good can identify a WO resource linked to SI-0 index 2 and transmit UL WUS through the WO resource to request SI-0 transmission.

[0349] When SS-to-WO mapping is determined based on N_max, such as in Alt-2, the terminal can select a WO associated with SS index n based on the SS index. For example, if a terminal receiving SS index 3 determines that the reception sensitivity of SS index 3 is good, it can identify the WO resource associated with SS index 3 and transmit UL WUS through the WO resource to request SI-0 transmission.

[0350] Alt-1 may have an advantage in terms of resource efficiency because it consumes relatively few WO resources, and Alt-2 may have an advantage in terms of simplicity in terms of terminal implementation complexity because WO resources are determined only by the SS index.

[0351] [Proposal #2] UL WUS Transmission

[0352] Through the above proposal #1, the terminal can identify UL WUS resources and select UL WUS resources for requesting SI-0 based on detection / decoding of SS bursts, and perform transmission. At this time, we propose power values ​​for WUS transmission and a retransmission method when the requested SI-0 is not received.

[0353] In the random access procedure of the existing 5G NR system, path loss can be measured using the SSB power value of the base station and the power value of the actual SSB reception, and the PRACH initial power value can be set based on the measured value. In addition, if a RACH failure occurs due to reception failure such as msg2 / 4 after a PRACH transmission, the number of PRACH retransmissions and / or the power ramping counter value is increased, and the PRACH transmission power value is increased by the power step value.

[0354] First, we propose a method for determining power values ​​for WUS transmission. Considering that the information that a terminal can receive signaled before requesting SI-0 is limited, the SS power value of the base station assumed by the terminal before requesting SI-0 can be predefined as a specific value. The specific value can be defined according to the frequency band and / or sync raster in which the SS is transmitted. For example, the terminal can assume that the transmission power value of an SS transmitted in a 900 MHz band is 33 dBm and that the transmission power value of an SS transmitted in a 3.5 GHz band is 23 dBm. Alternatively, N (e.g., N=2) candidates for SS transmission power values ​​can be predefined, and the SS transmission power value actually applied among the N can be signaled by the SS (or through a separate signal / channel that is FDM (and / or TDM) with the SSS (and / or PSS) or by utilizing a PSS / SSS sequence). For example, if SS power index 0 is defined in advance as 33 dBm and SS power index 1 is 23 dBm, and SS power index 0 (or index 1) is signaled through SS, the terminal receiving the signaling can perform path loss estimation assuming that the SS transmission power value is 33 dBm (or 23 dBm). At this time, the SS transmission power values ​​corresponding to the N value and / or N candidates can be defined differently depending on the frequency band and / or sync raster in which the SS is transmitted, and the signaling for the SS transmission power value can be provided to the terminal from the base station in another serving cell / carrier / BWP / non-serving cell / neighbor cell where the SS is not transmitted. Through this method, the terminal knows the SS transmission power value, and through path loss estimation, the terminal can calculate the power value at the time of initial UL WUS transmission, and perform WUS transmission using the power value.

[0355] Next, we propose a WUS retransmission method. As above, the terminal performs WUS transmission by applying the WUS initial transmission power value, and then expects to receive SI-0 after a certain point in time (T_A). However, if SI-0 is not received for a certain time interval (T_window) or X SI-0 cycles after the point in time T_A, the terminal can declare SI-0 failure. The determination of the T_A point in time is proposed in Proposal #3 below, and the T_window value and / or X and / or the SI-0 cycle can be predefined or set by the base station.

[0356] After an SI-0 failure, the terminal can increase the counter value for the SI-0 request and increase the power value. When the power increment is defined as power_inc, the power_inc value assumed by the terminal when requesting SI-0 can be predefined as a specific value. The power_inc value can be defined according to the frequency band and / or sync raster in which the SS is transmitted. For example, the terminal can assume that the power_inc value is 3 dB in the 900 MHz band and 2 dB in the 3.5 GHz band. Alternatively, N (e.g., N=2) candidates for the power_inc value can be predefined, and the power_inc value actually applied among the N can be signaled by the SS (or via a separate signal / channel that is FDM (and / or TDM) with the SSS (and / or PSS) or by utilizing the PSS / SSS sequence). For example, if power_inc index 0 is defined in advance as 3 dB and power_inc index 1 is 2 dB, and power_inc index 0 (or index 1) is signaled through SS, the terminal receiving the signaling can perform WUS retransmission assuming that the power_inc value is 3 dB (or 2 dB). In this case, the N value and / or the power_inc values ​​corresponding to the N candidates can be defined differently depending on the frequency band and / or sync raster in which the SS is transmitted, and the signaling for the power_inc value can be provided to the terminal from the base station in another serving cell / carrier / BWP / non-serving cell / neighbor cell where the SS is not transmitted. In this way, the terminal can increase the UL WUS transmission power by power_inc for each UL WUS retransmission for the same SS (index or burst).

[0357] Also, when retransmitting for the same SS (index or burst), the counter value is increased, and when the counter value reaches the max_cnt value, the UE can consider that the cell is barred or attempt initial access / cell (re)selection for another cell. At this time, the max_cnt value assumed by the UE when requesting SI-0 can be predefined as a specific value. The max_cnt value can be defined according to the frequency band and / or sync raster in which the SS is transmitted. For example, the UE can assume that the max_cnt value is 10 in the 900 MHz band and the power_inc value is 5 in the 3.5 GHz band. Alternatively, N (e.g., N=2) candidates for the max_cnt value can be predefined, and the max_cnt value that is actually applied among the N can be signaled by the SS (or via a separate signal / channel that is FDM (and / or TDM) with the SSS (and / or PSS) or by utilizing the PSS / SSS sequence). For example, if max_cnt index 0 is defined in advance as 10 and power_inc index 1 is 5, and max_cnt index 0 (or index 1) is signaled through SS, the terminal receiving the signaling can perform WUS retransmission assuming that the max_cnt value is 10 (or 5). In this case, the N value and / or the max_cnt values ​​corresponding to the N candidates can be defined differently depending on the frequency band and / or sync raster in which the SS is transmitted, and the signaling for the max_cnt value can be provided to the terminal from the base station in another serving cell / carrier / BWP / non-serving cell / neighbor cell in which the SS is not transmitted.

[0358] [Proposal #3] Receiving the requested SI-0

[0359] An agreement may be required between the UE and the base station regarding the distance from the time point (K1) when the UE transmits the UL WUS to the time point when the UE receives the requested SI-0. K1 may be the start / end boundary of the symbol / slot / subframe / half-frame / frame that contains the UL WUS, and the first SI-0 burst transmission occasion after Y time offsets (e.g., symbol / slot / msec / subframe / half-frame / frame) from K1 may be defined as T_A. Here, the value of Y may be predefined or may be a value set by the base station. For example, when there is an SS burst transmitted when SFN (system frame number) mod 2 = 0, it is assumed that the UE transmits a UL WUS in a specific slot n (=K1) belonging to SFN index 3, and the SI-0 burst is assumed to be transmitted from slot P within SFN mod 4 = 0. If Y=2 slots, the terminal can assume that it can receive SI-0 burst from slot P (=T_A) within SFN index 4, which is the first SI-0 burst transmission occasion after slot n+2.

[0360] FIG. 22 illustrates an SS Burst, an SI-0 burst, and a WO burst according to one embodiment.

[0361] As shown in the above Fig. 22, the SS periodicity (e.g., SS periodicity is T1-T0) and the WO burst period (e.g., WO periodicity is T3-T2) can be defined / set differently. If the reference point of the WO (time) offset such as SFN index=0 is T0, T2-T0 can mean the WO offset. When L (e.g., L=L_max) beam indices can be transmitted within one SS burst, WOs corresponding to N SS / beam indices can be transmitted within a WO burst, and if the SS-to-WO mapping ratio is 1, N can be L_max (by Alt-1 of the above proposal #1) or N_max (by Alt-2 of the above proposal #1). In addition, the interval between WO (groups) within a WO burst can also be defined / set through the above methods. A terminal transmits a UL WUS on a WO associated with a specific beam, and can expect to receive SI-0 from T_A, the first SI-0 burst transmission occasion Y hours after the corresponding transmission point K1. If SI-0 is not received for a certain time interval (T_window) or X SI-0 cycles after the corresponding point T_A, the terminal can declare SI-0 failure and perform WUS retransmission.

[0362] The transmission pattern (e.g., periodicity, offset, etc.) of SI-0-burst included in the above "SS-information", the time interval (and the periodicity) during which SI-0 is transmitted after an SI-0-burst request, can be predefined or signaled. Or, when the transmission of SI-0 can be indicated in the "SS-information", if a signaling that SI-0 is not transmitted is received, the terminal can recognize that SI-0 will not be transmitted thereafter. Or, the terminal can assume that SI-0 is continuously transmitted (e.g., for rate-matching purposes when receiving PDSCH such as SI-1, SIB, etc.) until SI-1 is successfully received after receiving SI-0, or until the random access procedure is completed and the connection is setup.

[0363] [Proposal #4] SSB measurement

[0364] In performing SSB-based intra / inter-frequency RRM measurement for neighbor cells in existing NR, measurement can be performed without decoding the PBCH (if time synchronization with the serving cell is guaranteed), or measurement accompanied by decoding the PBCH (if time synchronization with the serving cell is not guaranteed and information such as the SSB index and SFN index in the PBCH information is required). In this disclosure, we propose a method for performing measurement for cells to which SI-0 may not always be applied.

[0365] Whether the on-demand SI-0 procedure is in operation (or whether SI-0 is guaranteed to always be transmitted) can be signaled via SIB per PCI (physical cell identifier), per PCI list, or per frequency. In this case, when the terminal performs SS measurement for PCI / frequency where the on-demand SI-0 procedure is in operation or SI-0 may not be transmitted, the terminal can assume that timing synchronization with the serving cell is guaranteed (e.g., the terminal reception error between the serving cell and the cell that will perform the SS measurement is guaranteed to be Q us / ns or less). Alternatively, the base station can set / indicate a reception error value that the terminal can assume between the serving cell and the cell that will perform the SS measurement, so that the terminal can perform the SS measurement based on the error value (or after applying the error value).

[0366] Alternatively, the terminal performing the measurement can be enabled to transmit WUS and receive SI-0 for the PCI / frequency by providing UL WUS-related information for the PCI / frequency (e.g., some of the configuration information suggested in WUS Example #4 and / or some of the “SS-information”) from the serving cell.

[0367] Figure 23 is a diagram illustrating the operation of a terminal and a base station according to one embodiment. Figure 23 is an implementation example of at least some of the proposals described above, and the contents of the above proposals may be referenced even if not otherwise stated.

[0368] Referring to Figure 23, the base station may be saving energy by transmitting only SS-burst (A05) without transmitting SI-0.

[0369] Upon recognizing this, the terminal can select (A10) a UL WUS resource (based on the determined UL WUS resource and SS-index or PBCH-index) and transmit (A15) a UL WUS to perform initial access in the corresponding cell. Thereafter, the terminal can receive (A25) a PBCH burst and perform the initial access process.

[0370] As described above, it may not be efficient from an energy consumption perspective for a base station to always perform SSB transmission for a terminal that may attempt initial access. Considering that the base station may not always transmit the PBCH to reduce energy consumption, proposals regarding UL WUS resource configuration methods for requesting the PBCH, UL WUS transmission methods for terminals, methods for receiving the requested PBCH, and / or SSB measurement may be applied.

[0371] Figure 24 illustrates a flowchart of a method performed by a terminal according to one embodiment. Figure 24 is an implementation example of at least some of the proposals described above, and the contents of the proposals described above may be referenced even if not otherwise stated.

[0372] Referring to FIG. 24, the terminal can receive at least one SS block among multiple SS blocks included in an SS (synchronization signal) burst (B05).

[0373] The terminal can transmit an uplink signal for an on-demand PBCH (physical broadcast channel) request based on at least one SS block (B10).

[0374] The terminal can receive at least one PBCH block among a plurality of PBCH blocks included in a PBCH burst based on transmission of the uplink signal (B15).

[0375] The index of at least one PBCH block received by the terminal may be linked to the index of at least one SS block received.

[0376] The uplink resource for the above uplink signal may be determined based on at least one of (i) an index of the at least one SS block or (ii) an index of the at least one PBCH block linked to the index of the at least one SS block.

[0377] The above plurality of SS blocks may be L SS blocks transmitted from among a maximum of N SS blocks set for the SS burst.

[0378] For example, the plurality of PBCH blocks may include L PBCH blocks linked to the L SS blocks. The terminal may determine to receive a PBCH block having a PBCH block index m among the L PBCH blocks based on receiving an SS block having an SS block index n among the L SS blocks. The uplink resource may be determined based on the PBCH block index m.

[0379] For example, a plurality of uplink resources linked to the above N SS blocks can be set. The terminal can transmit the uplink signal through the uplink resource linked to the SS block index n based on receiving an SS block having an SS block index n among the L SS blocks.

[0380] The power of the above uplink signal can be determined based on a frequency band or synchronization raster of the at least one SS block.

[0381] The above PBCH burst may be the earliest PBCH burst located after a time offset Y from the transmission of the uplink signal among the periodically set PBCH bursts.

[0382] The at least one SS block may include configuration information related to transmission of the uplink signal.

[0383] The above multiple SS blocks may be PBCH-less SS blocks.

[0384] The above uplink signal may include at least one of a wake-up signal (WUS) or a random access channel.

[0385] Figure 25 illustrates a flowchart of a method performed by a terminal according to one embodiment. Figure 25 is an implementation example of at least some of the proposals described above, and the contents of the proposals described above may be referenced even if not otherwise stated.

[0386] Referring to FIG. 25, the base station can transmit at least one SS block among multiple SS blocks included in an SS (synchronization signal) burst (C05).

[0387] The base station can receive an uplink signal for an on-demand PBCH (physical broadcast channel) request from a terminal (C10).

[0388] The base station can transmit at least one PBCH block among a plurality of PBCH blocks included in a PBCH burst based on reception of the uplink signal (C15).

[0389] The index of at least one PBCH block may be linked to the index of at least one SS block.

[0390] The uplink resource for the above uplink signal may be determined based on at least one of (i) an index of the at least one SS block or (ii) an index of the at least one PBCH block linked to the index of the at least one SS block.

[0391] The above plurality of SS blocks may be L SS blocks transmitted from among a maximum of N SS blocks set for the SS burst.

[0392] For example, the plurality of PBCH blocks may include L PBCH blocks linked to the L SS blocks. An SS block having an SS block index n among the L SS blocks may be linked to a PBCH block having a PBCH block index m among the L PBCH blocks. An uplink resource for a terminal that has received an SS block index n may be determined based on the PBCH block index m.

[0393] For example, a plurality of uplink resources linked to the above N SS blocks can be set. The base station can receive the uplink signal from the receiving terminal through the uplink resource linked to the SS block index n for the SS block having the SS block index n among the L SS blocks.

[0394] The power of the above uplink signal can be determined based on a frequency band or synchronization raster of the at least one SS block.

[0395] The above PBCH burst may be the earliest PBCH burst located after a time offset Y from the reception of the uplink signal among the periodically set PBCH bursts.

[0396] The at least one SS block may include configuration information related to the uplink signal.

[0397] The above multiple SS blocks may be PBCH-less SS blocks.

[0398] The above uplink signal may include at least one of a wake-up signal (WUS) or a random access channel.

[0399] 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.

[0400] 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 scope of the present disclosure. Therefore, the above detailed description should not be construed as limiting in any respect, but rather as illustrative. The scope of the present disclosure should be determined by a reasonable interpretation of the appended claims, and all modifications within the scope of equivalents of the present disclosure are intended to be included within the scope of the present disclosure.

[0401] The present disclosure may be used in a terminal, base station, or other equipment of a wireless mobile communication system.

Claims

There is a method performed by the terminal, SS(synchronization signal)-Receive at least one SS block among multiple SS blocks included in a burst; Transmitting an uplink signal for an on-demand PBCH (physical broadcast channel) request based on at least one SS block; and Receiving at least one PBCH block among a plurality of PBCH blocks included in a PBCH burst based on transmission of the above uplink signal, The index of at least one PBCH block received by the terminal is linked to the index of at least one SS block received, A method wherein the uplink resources for the uplink signal are determined based on at least one of (i) an index of the at least one SS block or (ii) an index of the at least one PBCH block linked to the index of the at least one SS block. In the first paragraph, A method wherein the above plurality of SS blocks are L SS blocks transmitted from among a maximum of N SS blocks set for the SS burst. In the second paragraph, The above plurality of PBCH blocks include L PBCH blocks linked to the L SS blocks, The terminal determines to receive a PBCH block having a PBCH block index m among the L PBCH blocks based on receiving an SS block having an SS block index n among the L SS blocks, A method in which the above uplink resource is determined based on the PBCH block index m. In the second paragraph, Multiple uplink resources linked to the above N SS blocks are set, A method in which the terminal transmits the uplink signal through an uplink resource associated with the SS block index n, based on receiving an SS block having an SS block index n among the L SS blocks. In the first paragraph, A method wherein the power of the uplink signal is determined based on a frequency band or synchronization raster of at least one SS block. In the first paragraph, A method wherein the above PBCH burst is the earliest PBCH burst located after a time offset Y from the transmission of the uplink signal among the periodically set PBCH bursts. In the first paragraph, A method wherein at least one SS block includes configuration information related to transmission of the uplink signal. In the first paragraph, A method wherein the above plurality of SS blocks are PBCH-less SS blocks. In the first paragraph, A method wherein the uplink signal comprises at least one of a wake-up signal (WUS) or a random access channel. A non-transitory computer-readable recording medium having recorded thereon a program for performing the method described in claim 1. In the device, at least one processor; and At least one memory configured to store instructions that are executed by said at least one processor to cause said at least one processor to perform operations, The operations of the above processor are: SS(synchronization signal)-Receive at least one SS block among multiple SS blocks included in a burst; Transmitting an uplink signal for an on-demand PBCH (physical broadcast channel) request based on at least one SS block; and Receiving at least one PBCH block among a plurality of PBCH blocks included in a PBCH burst based on transmission of the above uplink signal, The index of at least one PBCH block received by the device is linked to the index of at least one SS block received, A device wherein the uplink resource for the uplink signal is determined based on at least one of (i) an index of the at least one SS block or (ii) an index of the at least one PBCH block linked to an index of the at least one SS block. In paragraph 11, The above device further comprises a transmitter and receiver, The above device is a terminal device. In paragraph 11, The above device is a processing device configured to control a terminal. In a method performed by a base station, SS(synchronization signal)-transmitting at least one SS block among multiple SS blocks included in a burst; Receiving an uplink signal for an on-demand PBCH (physical broadcast channel) request from a terminal; and Including transmitting at least one PBCH block among a plurality of PBCH blocks included in a PBCH burst based on reception of the above uplink signal, The index of at least one PBCH block is linked to the index of at least one SS block, A method wherein the uplink resources for the uplink signal are determined based on at least one of (i) an index of the at least one SS block or (ii) an index of the at least one PBCH block linked to the index of the at least one SS block. At the base station, at least one processor; and At least one memory configured to store instructions that are executed by said at least one processor to cause said at least one processor to perform operations, The operations of the above processor are: SS(synchronization signal)-transmitting at least one SS block among multiple SS blocks included in a burst; Receiving an uplink signal for an on-demand PBCH (physical broadcast channel) request from a terminal; and Including transmitting at least one PBCH block among a plurality of PBCH blocks included in a PBCH burst based on reception of the above uplink signal, The index of at least one PBCH block is linked to the index of at least one SS block, A base station, wherein the uplink resources for the uplink signal are determined based on at least one of (i) an index of the at least one SS block or (ii) an index of the at least one PBCH block linked to the index of the at least one SS block.

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