Apparatus and method for turning on / off synchronization signal and broadcast channel signal in wireless communication system

Abstract

The disclosure relates to turning on / off synchronization signal / physical broadcast channel blocks in a wireless communication system. The method of operating a terminal may comprise the steps of: receiving downlink control information (DCI) related to system information; acquiring allocation information for receiving system information based on the DCI; receiving system information based on the allocation information; acquiring first information related to a position of a synchronization signal / physical broadcast channel block (SSB) included in the system information; receiving second information related to turn-on or turn-off of the SSB; and receiving at least one of the SSBs based on the first information and the second information.

Description

Technical Field

[0001] The following description relates to a wireless communication system, and an apparatus and method for turning on / off a synchronization signal / broadcast channel signal in the wireless communication system. Background Art

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

[0003] In particular, since a large number of communication devices require a large communication capacity, an enhanced mobile broadband (eMBB) communication technology is being proposed compared to a conventional radio access technology (RAT). In addition, not only a large-scale machine type communication (massive MTC) that provides various services anytime and anywhere by connecting multiple devices and objects is being proposed, but also a communication system that takes into account services / user terminal devices (UEs) that are sensitive to reliability and latency is being proposed. Various technical configurations are proposed for this purpose. Summary of the invention

[0004] Technical issues

[0005] The present disclosure may provide an apparatus and method for turning on / off a synchronization signal / broadcast channel signal in a wireless communication system.

[0006] The present disclosure may provide an apparatus and method for dynamically turning on / off at least one SSB (Synchronization Signal / Physical Broadcast Channel Block) in a wireless communication system.

[0007] The present disclosure may provide an apparatus and method for dynamically signaling on / off of at least one SSB in a wireless communication system.

[0008] The present disclosure may provide an apparatus and method for mapping bits indicating on / off of at least one SSB and an SSB index in a wireless communication system.

[0009] The present disclosure may provide an apparatus and method for performing a random access procedure based on dynamically turned-on / off SSB in a wireless communication system.

[0010] The present disclosure may provide an apparatus and method for determining a RACH (random access channel) timing based on a dynamically turned-on / off SSB in a wireless communication system.

[0011] The present disclosure may provide an apparatus and method for controlling a random access response (RAR) window based on a dynamically turned-on / off SSB in a wireless communication system.

[0012] The present disclosure may provide an apparatus and method for determining a PUSCH (Physical Uplink Shared Channel) timing based on a dynamically turned-on / off SSB in a wireless communication system.

[0013] The present disclosure may provide an apparatus and method for determining a monitoring opportunity (MO) of a physical downlink shared channel (PDCCH) based on a SSB dynamically turned on / off in a wireless communication system.

[0014] The present disclosure may provide an apparatus and method for performing at least one of radio link monitoring (RLM), candidate beam detection (CBD), beam failure detection (BFD), or mobility management operations based on SSB dynamically turned on / off in a wireless communication system.

[0015] The present disclosure may provide an apparatus and method for controlling handover related operations based on dynamically turned-on / off SSB in a wireless communication system.

[0016] The present disclosure may provide an apparatus and method for configuring SSB measurement timing configuration (SMTC) based on at least one of the capabilities of a terminal, a DRX configuration, or an activity time of a base station in a wireless communication system.

[0017] The present disclosure may provide an apparatus and method for setting SSB-related parameters based on NES (Network Energy Saving)-related capabilities of a terminal in a wireless communication system.

[0018] The present disclosure may provide an apparatus and method for setting a handover-related threshold based on an NES-related capability of a terminal in a wireless communication system.

[0019] The technical objectives to be achieved by the present disclosure are not limited to the contents mentioned above, and those skilled in the art to which the technical configuration of the present disclosure is applied can consider other technical objectives not mentioned therein from the embodiments of the present disclosure to be described below.

[0020] Technical Solution

[0021] As an example of the present disclosure, a method for operating a terminal in a wireless communication system may include: receiving downlink control information (DCI) related to system information; obtaining allocation information for receiving the system information based on the DCI; receiving the system information based on the allocation information; obtaining first information related to the position of a synchronization signal / physical broadcast channel block (SSB) included in the system information; receiving second information related to turning on or off the SSB; and receiving at least one of the SSBs based on the first information and the second information.

[0022] As an example of the contents of the present disclosure, a method for operating a base station in a wireless communication system may include: sending downlink control information (DCI) related to system information; sending system information including first information related to the location of a synchronization signal / physical broadcast channel block (SSB) based on the allocation information included in the DCI; sending second information related to turning on or off the SSB; and sending at least one of the SSBs based on the first information and the second information.

[0023] As an example of the present disclosure, a terminal in a wireless communication system may include a transceiver and a processor connected to the transceiver. The processor may receive downlink control information (DCI) related to system information, obtain allocation information for receiving system information based on the DCI, receive system information based on the allocation information, obtain first information related to the position of a synchronization signal / physical broadcast channel block (SSB) included in the system information, receive second information related to turning on or off the SSB, and receive at least one of the SSBs based on the first information and the second information.

[0024] As an example of the present disclosure, a base station in a wireless communication system may include a transceiver and a processor connected to the transceiver. The processor may send downlink control information (DCI) related to system information, send system information including first information related to the location of a synchronization signal / physical broadcast channel block (SSB) based on allocation information included in the DCI, send second information related to turning on or off the SSB, and send at least one of the SSB based on the first information and the second information.

[0025] As an example of the present disclosure, a communication device may include at least one processor and at least one computer memory, the at least one computer memory being connected to the at least one processor and configured to store instructions, the instructions directing operations performed by the at least one processor. The operations may include: receiving downlink control information (DCI) related to system information; obtaining allocation information for receiving the system information based on the DCI; receiving the system information based on the allocation information; obtaining first information related to the location of a synchronization signal / physical broadcast channel block (SSB) included in the system information; receiving second information related to turning on or off the SSB; and receiving at least one of the SSBs based on the first information and the second information.

[0026] As an example of the present disclosure, a non-transitory computer-readable medium storing at least one instruction includes the at least one instruction that can be executed by a processor. The at least one instruction can control the device to perform the following operations: receiving downlink control information (DCI) related to system information; obtaining allocation information for receiving the system information based on the DCI; receiving the system information based on the allocation information; obtaining first information related to the position of a synchronization signal / physical broadcast channel block (SSB) included in the system information; receiving second information related to the opening or closing of the SSB; and receiving at least one SSB among the SSBs based on the first information and the second information.

[0027] The above-mentioned aspects of the present disclosure are only a part of exemplary embodiments of the present disclosure, and those skilled in the art can derive and understand various embodiments reflecting the technical features of the present disclosure based on the following detailed description of the present disclosure.

[0028] Beneficial Effects

[0029] As is apparent from the above description, the embodiments of the present disclosure have the following effects.

[0030] According to the present disclosure, it is possible to efficiently control turning on / off a synchronization signal / broadcast channel signal transmitted from a base station.

[0031] Those skilled in the art will appreciate that the effects that can be achieved by the embodiments of the present disclosure are not limited to the above effects, and other beneficial effects of the present disclosure will be more clearly understood from the following detailed description. That is, those skilled in the art can derive unexpected effects according to the embodiments of the present disclosure from the embodiments of the present disclosure. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] The accompanying drawings are provided to help understand the present disclosure, and may provide embodiments of the present disclosure together with the detailed description. However, the technical features of the present disclosure are not limited to specific drawings, and the features disclosed in each drawing may be combined with each other to form new embodiments. The reference numerals in each drawing may refer to structural elements.

[0033] Figure 1 An example of a structure of a wireless communication system to which the present disclosure can be applied is illustrated.

[0034] Figure 2 An example of a wireless device applicable to the present disclosure is illustrated.

[0035] Figure 3 The frame structure in a wireless communication system to which the present disclosure can be applied is illustrated.

[0036] Figure 4 An example of a resource grid in a wireless communication system to which the present disclosure can be applied is illustrated.

[0037] Figure 5 An example of a physical resource block in a wireless communication system to which the present disclosure can be applied is illustrated.

[0038] Figure 6 An example of a time slot structure in a wireless communication system to which the present disclosure can be applied is illustrated.

[0039] Figure 7 An example of a physical channel used in a wireless communication system to which the present disclosure can be applied and an example of a general signal transmission and reception method using the physical channel are illustrated.

[0040] Figure 8 The structure of an SSB (Synchronization Signal and Broadcast Channel Block) applicable to the present disclosure is illustrated.

[0041] Fig. 9 The transmission of SSB applicable to the present disclosure is illustrated.

[0042] Fig.10 Examples of SSB candidate positions applicable to the present disclosure are illustrated.

[0043] Fig.11 An example of downlink time synchronization information applicable to the present disclosure is illustrated.

[0044] Fig.12 An example of a process for receiving an SSB (Synchronization Signal / Physical Broadcast Channel Block) in a wireless communication system according to an embodiment of the present disclosure is illustrated.

[0045] Fig.13 An example of a process for transmitting SSB in a wireless communication system according to an embodiment of the present disclosure is illustrated.

[0046] Fig.14 An example of a process for receiving SSB on / off information in a bitmap form in a wireless communication system according to an embodiment of the present disclosure is illustrated.

[0047] Fig.15 An example of a process for transmitting a RACH preamble based on SSB on / off information in a wireless communication system according to an embodiment of the present disclosure is illustrated.

[0048] Fig.16 An example of a procedure for performing a RACH procedure based on SSB on / off in a wireless communication system according to an embodiment of the present disclosure is illustrated.

[0049] Fig.17 An example of a RACH procedure based on SSB dynamically turned on / off in a wireless communication system according to an embodiment of the present disclosure is illustrated.

[0050] Fig.18 An example of a process for performing a designated operation based on SSB on / off information in a wireless communication system according to an embodiment of the present disclosure is illustrated.

[0051] Fig.19 An example of a process for controlling a PDCCH (Physical Downlink Control Channel) MO (Monitoring Occasion) based on SSB on / off information in a wireless communication system according to an embodiment of the present disclosure is illustrated.

[0052] Fig. 20 An example of a process for measuring SSB based on SMTC in a wireless communication system according to an embodiment of the present disclosure is illustrated.

[0053] Fig.21 An example of a process for setting SSB-related parameters according to terminal capabilities in a wireless communication system according to an embodiment of the present disclosure is illustrated.

[0054] Fig. 22 An example of a process for controlling a threshold related to mobility according to terminal capabilities in a wireless communication system according to an embodiment of the present disclosure is illustrated. DETAILED DESCRIPTION

[0055] The embodiments of the present disclosure described below are combinations of elements and features of the present disclosure in a particular form. Unless otherwise mentioned, elements or features may be considered to be selective. Each element or feature may be put into practice without being combined with other elements or features. In addition, embodiments of the present disclosure may be constructed by combining some elements and / or features. The order of operations described in the embodiments of the present disclosure may be rearranged. Some structures or elements of any one embodiment may be included in another embodiment and may be replaced by the corresponding structures or features of another embodiment.

[0056] In the description of the drawings, processes or steps that render the scope of the present disclosure unnecessarily ambiguous will be omitted, and processes or steps that can be understood by those skilled in the art will be omitted.

[0057] Throughout the specification, when a part "includes" or "comprises" a component, this indicates that other components are not excluded and may further be included, unless otherwise specified. The terms "unit", "-or / er" and "module" described in this specification indicate a unit for processing at least one function or operation, which can be implemented by hardware, software or a combination thereof. In addition, "a" or "an", "one", "the", etc. in the context of the present disclosure (more specifically, in the context of the appended claims) may include singular and plural expressions, unless otherwise specified in the specification or unless the context clearly indicates otherwise.

[0058] In the embodiments of the present disclosure, the data transmission and reception relationship between the base station (BS) and the mobile station is mainly described. The BS refers to the terminal node of the network, which directly communicates with the mobile station. The specific operation described as being performed by the BS can be performed by the upper node of the BS.

[0059] That is, it is apparent that in a network composed of a plurality of network nodes including a BS, various operations performed for communication with a mobile station may be performed by the BS or network nodes other than the BS. The term "BS" may be replaced with a fixed station, a Node B, an evolved Node B (eNode B or eNB), an advanced base station (ABS), an access point, etc.

[0060] In an embodiment of the present disclosure, the term terminal may be replaced with UE, mobile station (MS), subscriber station (SS), mobile subscriber station (MSS), mobile terminal, advanced mobile station (AMS), etc.

[0061] The transmitter is a fixed and / or mobile node that provides data services or voice services, and the receiver is a fixed and / or mobile node that receives data services or voice services. Therefore, on the uplink (UL), the mobile station can act as a transmitter and the BS can act as a receiver. Similarly, on the downlink (DL), the mobile station can act as a receiver and the BS can act as a transmitter.

[0062] The embodiments of the present disclosure may be supported by at least one of the standard specifications disclosed for wireless access systems including the Institute of Electrical and Electronics Engineers (IEEE) 802.xx system, the 3rd Generation Partnership Project (3GPP) system, the 3GPP Long Term Evolution (LTE) system, the 3GPP Fifth Generation (5G) New Radio (NR) system, and the 3GPP2 system. Specifically, the embodiments of the present disclosure may be supported by the standard specifications 3GPP TS 36.211, 3GPP TS 36.212, 3GPP TS 36.213, 3GPP TS36.321, and 3GPP TS 36.331.

[0063] In addition, the embodiments of the present disclosure are applicable to other radio access systems and are not limited to the above-mentioned systems. For example, the embodiments of the present invention are applicable to systems applied after the 3GPP 5G NR system and are not limited to a specific system.

[0064] That is, steps or parts that are not described to clarify the technical features of the present disclosure may be supported by those documents. In addition, all terms as proposed herein may be interpreted by standard documents.

[0065] Embodiments of the present disclosure will now be described in detail with reference to the accompanying drawings. The detailed description given below with reference to the accompanying drawings is intended to explain exemplary embodiments of the present disclosure, rather than to show the only embodiments that can be implemented according to the present disclosure.

[0066] The following detailed description includes specific terms in order to provide a thorough understanding of the present disclosure. However, it is obvious to those skilled in the art that other terms may be used to replace specific terms without departing from the technical spirit and scope of the present disclosure.

[0067] The embodiments of the present disclosure can be applied to various radio access systems such as code division multiple access (CDMA), frequency division multiple access (FDMA), time division multiple access (TDMA), orthogonal frequency division multiple access (OFDMA), single carrier frequency division multiple access (SC-FDMA), etc.

[0068] Hereinafter, in order to clarify the following description, the description is based on the 3GPP communication system (e.g., LTE, NR, etc.), but the technical spirit of the present disclosure is not limited thereto. LTE may refer to the technology after 3GPP TS 36.xxx version 8. Specifically, the LTE technology after 3GPP TS 36.xxx version 10 may be referred to as LTE-A, and the LTE technology after 3GPP TS 36.xxx version 13 may be referred to as pre-LTE-A. 3GPP NR may refer to the technology after TS 38.xxx version 15. 3GPP 6G may refer to the technology after TS version 17 and / or version 18. "xxx" may refer to the detailed number of the standard document. LTE / NR / 6G may be collectively referred to as the 3GPP system.

[0069] 3GPP 6G may refer to post-3GPP NR technology based on the 3GPP system. 3GPP 6G may not be limited to a version or a specific TS document, and its name may have a different form from 3GPP 6G. That is, 3GPP 6G may refer to a technology introduced after 3GPP NR, and is not limited to a specific form.

[0070] The following description will mainly focus on the 3GPP NR system, but is not limited thereto, and can be applied to 3GPP 6G. In addition, the content described below may be partially modified to be used in consideration of the 3GPP 6G system, and is not limited to a specific form. However, in the following, for ease of explanation, the 3GPP NR system will be mainly described. For the background technology, terms, abbreviations, etc. used in this disclosure, please refer to the matters described in the standard documents published before this disclosure. For example, standard documents 36.xxx and 38.xxx may be referenced.

[0071] Overall system

[0072] As more and more communication devices require greater communication capacity, the demand for mobile broadband communications that are more enhanced than existing radio access technologies (RATs) is rising. In addition, large-scale machine type communications (MTC) that provide various services anytime and anywhere by connecting multiple devices and things is also one of the main issues worth considering in next-generation communications. In addition, the design of communication systems that consider services / terminals that are sensitive to reliability and latency is also under discussion. Therefore, the introduction of next-generation RATs that consider enhanced mobile broadband communications (eMBB), massive MTC (mMTC), ultra-reliable low-latency communications (URLLC), etc. is under discussion, and for convenience, the corresponding technology is referred to as NR in this disclosure. NR is an expression representing an example of 5G RAT.

[0073] The new RAT system including NR uses an OFDM transmission method or a similar transmission method. The new RAT system may follow OFDM parameters different from those of LTE. Alternatively, the new RAT system may follow the parameter set of the existing LTE / LTE-A as is, but support a wider system bandwidth (e.g., 100MHz). Alternatively, a cell may support multiple parameter sets. In other words, terminals operating according to different parameter sets may coexist in one cell.

[0074] A parameter set corresponds to one subcarrier spacing in the frequency domain. Because the reference subcarrier spacing is scaled by an integer N, different parameter sets can be defined.

[0075] In addition, new RAT systems including 6G may be considered as next generation RATs. New RAT systems including 6G may consider i) very high data speeds per device, ii) a large number of connected devices, iii) global connectivity, iv) very low latency, v) reduced energy consumption of battery-free IoT devices, vi) ultra-high reliability connectivity, and vii) connectivity intelligence with machine learning capabilities, but are not limited thereto. In view of the above, new RAT systems including 6G may consider using the terahertz (THz) band, i.e., a frequency higher than the NR system, for wider bandwidth and higher transmission speeds. RAT systems including 6G may overcome existing limitations by applying artificial intelligence / machine learning (AI / ML), but may not be limited thereto.

[0076] Figure 1 The structure of a wireless communication system to which the present disclosure can be applied is illustrated. Figure 1 , NG-RAN consists of gNBs that provide control plane (RRC) protocol terminations for the NG-Radio Access (NG-RA) user plane (i.e., new access stratum (AS) sublayer / packet data convergence protocol (PDCP) / radio link control (RLC) / MAC / PHY) and UE. The gNBs are interconnected through the Xn interface. In addition, the gNBs are connected to the new generation core (NGC) through the N2 interface. More specifically, the gNB is connected to the access and mobility management function (AMF) through the N2 interface and to the user plane function (UPF) through the N3 interface. Figure 1 It can be based on the structure of the NR system. Figure 1 The structure can be used in the 6G system as it is or by being partially modified, and is not limited to a specific form.

[0077] Figure 2 An example of a wireless device applicable to the present disclosure is illustrated.

[0078] refer to Figure 2The wireless device 200 may send / receive radio signals via various wireless access technologies (e.g., LTE, LTE-A, pre-LTE-A, NR, 5G, 5G-A, 6G). The wireless device 200 may include at least one processor 202 and at least one memory 204, and may further include at least one transceiver 206 and / or at least one antenna 208.

[0079] The processor 202 may be configured to control the memory 204 and / or the transceiver 206 and implement the description, function, process, proposal, method and / or operation flow chart disclosed in this document. For example, the processor 202 may generate a first information / signal by processing the information in the memory 204, and then send a radio signal including the first information / signal through the transceiver 206. In addition, the processor 202 may receive a radio signal including a second information / signal through the transceiver 206, and then store information obtained from the signal processing of the second information / signal in the memory 204. The memory 204 may be connected to the processor 202 and store various information associated with the operation of the processor 202. For example, the memory 204 may store software code including instructions for implementing part or all of the processes controlled by the processor 202 or for implementing the description, function, process, proposal, method and / or operation flow chart disclosed in this document. 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 transmit and / or receive radio signals through at least one antenna 208. The transceiver 206 may be a transmitter and / or a receiver. The transceiver 206 may be used interchangeably with a radio frequency (RF) unit. In the present disclosure, a wireless device may refer to a communication modem / circuit / chip.

[0080] Hereinafter, the hardware elements of the wireless device 200 will be described in further detail. Although not limited thereto, at least one processor 202 may implement at least one protocol layer (e.g., functional layers such as physical (PHY), medium 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 description, function, process, proposal, method, and / or operation flow chart disclosed in this document. At least one processor 202 may generate a message, control information, data, or information according to the description, function, process, proposal, method, and / or operation flow chart disclosed in this document. At least one processor 202 may generate a signal (e.g., a baseband signal) including a PDU, SDU, message, control information, data, or information according to the function, process, proposal, and / or method 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 PDUs, SDUs, messages, control information, data, or information according to the descriptions, functions, processes, proposals, methods, and / or operational flow charts disclosed in this document.

[0081] At least one processor 202 may be referred to as a controller, a microcontroller, a microprocessor, or a microcomputer. At least one processor 202 may be implemented by hardware, firmware, software, or a combination thereof. As an example, at least one application specific integrated circuit (ASIC), at least one digital signal processor (DSP), at least one digital signal processing device (DSPD), at least one programmable logic device (PLD), or at least one field programmable gate array (FPGA) may be included in at least one processor 202. The description, functions, processes, proposals, methods, and / or operational flowcharts disclosed in this document may be implemented using firmware or software, and the firmware or software may be implemented to include modules, processes, or functions. Firmware or software configured to execute the description, functions, processes, proposals, methods, and / or operational flowcharts disclosed in this document may be included in at least one processor 202, or may be stored in at least one memory 204 and executed by at least one processor 202. The description, functions, processes, proposals, methods, and / or operational flowcharts disclosed in this document may be implemented using firmware or software in the form of code, instructions, and / or instruction sets.

[0082] At least one memory 204 may be connected to at least one processor 202 and store various forms of data, signals, messages, information, programs, codes, instructions, and / or instructions. At least one memory 204 may 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 disk, a register, a cache memory, a computer-readable storage medium, and / or a combination thereof. At least one memory 204 may be located inside and / or outside of at least one processor 202. In addition, at least one memory 204 may be connected to at least one processor 202 via various technologies such as a wired or wireless connection.

[0083] At least one transceiver 206 can send user data, control information, and wireless signals / channels mentioned in the method and / or operation flow chart of this document to at least one other device. At least one transceiver 206 can receive user data, control information, and wireless signals / channels mentioned in the description, function, process, proposal, method, and / or operation flow chart 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 send and receive radio signals. For example, at least one processor 202 can control at least one transceiver 206 to send user data, control information, or radio signals to at least one other device. In addition, at least one processor 202 can control at least one transceiver 206 to receive user data, control information, or radio signals from at least one other device. In addition, at least one transceiver 206 can be connected to at least one antenna 208, and at least one transceiver 206 can be configured to send and receive user data, control information, and radio signals / channels mentioned in the description, function, process, proposal, method, and / or operation flow chart 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 received radio signals / channels from RF band signals to baseband signals in order to facilitate processing of received user data, control information, and radio signals / channels using at least one processor 202. At least one transceiver 206 may convert user data, control information, and radio signals / channels processed using at least one processor 202 from baseband signals to RF band signals. To this end, at least one transceiver 206 may include an (analog) oscillator and / or a filter.

[0084] refer to Figure 2The components of the described wireless device may be referred to by other terms from the functional aspect. For example, the processor 202 may be referred to as a control unit, the transceiver 206 may be referred to as a communication unit, and the memory 204 may be referred to as a storage unit. In some cases, the communication unit may be used to mean at least a part of the processor 202 and the transceiver 206.

[0085] refer to Figure 2 The structure of the wireless device described may be understood as the structure of at least a portion of various devices. As an example, the structure may be at least a portion of various devices (e.g., a robot, a vehicle, an XR device, a handheld device, a home appliance, an IoT device, an AI device / server, etc.). In addition, according to various embodiments, in addition to Figure 2 In addition to the components illustrated in the figure, the device may further include other components.

[0086] For example, the device may be a handheld device such as a smart phone, a smart tablet, a wearable device (e.g., a smart watch, smart glasses), and a handheld computer (e.g., a laptop computer, 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 connecting to another device (e.g., an audio input / output port, a video input / output port); and an input / output unit for inputting and outputting video information / signals, audio information / signals, data, and / or information input from a user.

[0087] For example, the device may be a mobile device such as a mobile robot, a vehicle, a train, a manned / unmanned aerial vehicle (AV), and a ship. In this case, the device may further include at least one of the following: a drive unit including at least one of an engine, a motor, a power train, wheels, brakes, and a steering device of the device; a power supply unit that supplies power and includes a wired / wireless charging circuit, a battery, etc.; a sensor unit that senses state information, environmental information, and user information of the device or the surroundings of the device; an automatic driving unit that performs functions such as route maintenance, speed control, and destination setting; and a position measurement unit that obtains mobile object position information through a global positioning system (GPS) and various sensors.

[0088] For example, the device may be an XR device such as an HMD, a head-up display (HUD) provided in a vehicle, a TV, a smartphone, a wearable device, a home appliance device, a digital signage, a vehicle, and a robot. 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 and data from the outside and outputs a generated XR object; and a sensor unit that senses state information, environmental information, and user information of the device or the surroundings of the device.

[0089] For example, the device may be a robot, which may be classified according to the purpose or field of use as industrial use, medical use, home use, military use, etc. In this case, the device may further include at least one of: a sensor unit that senses state information, environmental information, and user information of the device or the surroundings of the device; and a drive unit that moves robot joints and performs various other physical operations.

[0090] For example, the device may be an AI device such as a TV, a projector, a smartphone, a PC, a laptop, a digital broadcast terminal, a tablet, a wearable device, a set-top box (STB), a radio, a washing machine, a refrigerator, a digital signage, a robot, and a vehicle. In this case, the device may further include at least one of: an input unit that obtains various types of data from the outside; an output unit that generates an output associated with vision, hearing, or touch; a sensor unit that senses state information, environmental information, and user information of the device or the surroundings of the device; and a training unit that uses learning data to learn a model composed of an artificial neural network. Figure 2 The structure of the wireless device illustrated in the example can be understood as a part of a RAN node (e.g., a base station, a DU, a RU, a RRH, etc.). That is, Figure 2 The device illustrated in the example may be a RAN node. In this case, the device may further include a wired transceiver for fronthaul and / or backhaul communication. However, in the case where the fronthaul and / or backhaul communication is based on wireless communication, Figure 2 The at least one transceiver 206 illustrated in FIG. 2 may be used for fronthaul and / or backhaul communications and may not include a wired transceiver.

[0091] Figure 3 The frame structure in a wireless communication system to which the present disclosure can be applied is illustrated.

[0092] The NR system may support multiple parameter sets. Here, the parameter set may be defined by a subcarrier spacing and a cyclic prefix (CP) overhead. Here, multiple subcarrier spacings may be derived by scaling the default (reference) subcarrier spacing by an integer N (or μ). In addition, although it is assumed that very low subcarrier spacing is not used in very high carrier frequencies, the parameter set used herein may be selected independently of the frequency band. In addition, various frame structures according to multiple parameter sets may be supported in the NR system.

[0093] In the following, OFDM parameter sets and frame structures that can be considered in the NR system will be described. The various OFDM parameter sets supported in the NR system can be defined as shown in Table 1 below.

[0094] [Table 1]

[0095] μ <![CDATA[Δy=2 μ ·15[kHz]]]> CP 0 15 normal 1 30 normal 2 60 Normal, Extended 3 120 normal 4 240 normal

[0096] NR supports multiple parameter sets (or subcarrier spacing (SCS)) to support various 5G services. For example, when the SCS is 15kHz, a wide area of ​​the traditional cellular band is supported, and when the SCS is 30kHz / 60kHz, dense urban areas, lower latency and wider carrier bandwidth are supported, and when the SCS is 60kHz or higher, bandwidth greater than 24.25GHz is supported to overcome phase noise.

[0097] The NR frequency band is defined as two types of frequency ranges (FR1, FR2). FR1 and FR2 can be configured as shown in Table 2 below. In addition, FR2 may mean millimeter wave (mmW).

[0098] [Table 2]

[0099] Frequency range specification Corresponding frequency range Subcarrier spacing FR1 410MHz-7125MHz 15, 30, 60kHz FR2 24250MHz-52600MHz 60, 120, 240kHz

[0100] Regarding the frame structure in the NR system, the sizes of various fields in the time domain are expressed in T c =1 / (Δf max ·N f ) is expressed in multiples of the time unit. Here, Δf max 480·10 3 Hz, and N f is 4096. Downlink and uplink transmissions are configured (organized) with T f =1 / (Δf max ·N f / 100)T c =10ms duration radio frame. Here, the radio frames are respectively configured with T sf =(Δf max ·N f / 1000)T c=10 subframes of duration of 1ms. In this case, there is one set of frames for uplink and one set of subframes for downlink. In addition, the transmission in uplink frame number i from the terminal should start T earlier than the corresponding downlink frame in the corresponding terminal. TA =(N TA +N TA，offset )T c For the subcarrier spacing configuration μ, the time slots in the subframe are The time slots in a radio frame are numbered in ascending order of A time slot is configured with A continuous OFDM symbol configuration is determined based on the CP Time slot in subframe The start time is the same as the OFDM symbol in the same subframe It is impossible for all terminals to perform transmission and reception at the same time, which means that not all OFDM symbols of a downlink time slot or an uplink time slot are available.

[0101] Table 3 shows the number of OFDM symbols per time slot in a normal CP Number of time slots per radio frame and the number of time slots per subframe And Table 4 represents the number of OFDM symbols per slot, the number of slots per radio frame, and the number of slots per subframe in the extended CP.

[0102] [Table 3]

[0103]

[0104] [Table 4]

[0105]

[0106] Figure 3 This is an example about μ=2 (SCS is 60 kHz), and referring to Table 3, 1 subframe may include 4 slots. Figure 3 1 subframe = {1, 2, 4} slots shown in is an example, and the number of slots that may be included in 1 subframe is as defined in Table 3 or Table 4. In addition, a mini-slot may include 2, 4, or 7 symbols or more or less.

[0107] Regarding the physical resources in the NR system, antenna ports, resource grids, resource elements, resource blocks, carrier parts, etc. can be considered. Hereinafter, the physical resources that can be considered in the NR system will be described in detail.

[0108] First, with respect to antenna ports, the antenna ports are defined so that the channel carrying the symbol in the antenna port can be inferred from the channel carrying another symbol in the same antenna port. When the large-scale characteristics of the channel carrying the symbol in one antenna port can be inferred from the channel carrying the symbol in another antenna port, the two antenna ports can be said to be in a quasi-co-location or quasi-co-location (QC / QCL) relationship. In this case, the large-scale characteristics include one or more of delay spread, Doppler spread, frequency offset, average received power, and receive timing.

[0109] In the 6G system, communication can be performed at the above-mentioned THz frequency band higher than the millimeter wave (mmW) frequency, and the same Figure 3 The same frame structure as shown, or a separate frame structure for the 6G system may be used, but is not limited to a specific form.

[0110] Figure 4 A resource grid in a wireless communication system to which the present disclosure can be applied is illustrated.

[0111] refer to Figure 4 , as an illustrative description, the resource grid is configured in the frequency domain with subcarriers, and one subframe is configured with 14·2 μ OFDM symbols, but the resource grid and subframe are not limited to this. In the NR system, the transmitted signal consists of OFDM symbols and One or more resource grids for each subcarrier. Here, represents the maximum transmission bandwidth, which may differ between uplink and downlink and between parameter sets. In this case, one resource grid can be configured for each μ and antenna port p. Each element of the resource grid for μ and antenna port p is called a resource element and is uniquely identified by an index pair (k, l'). Here, k = 0, ..., is an index in the frequency domain, and l'=0,..., refers to the position of a symbol in a subframe. When referring to a resource element in a slot, an index pair (k, l) is used. Here, l = 0, ..., The resource element (k, l') for μ and antenna port p corresponds to the complex value When there is no risk of confusion or no specific antenna port or parameter set is specified, the indices p and μ can be discarded and the complex value can be or a k，l′ In addition, a resource block (RB) is defined as consecutive subcarriers.

[0112] Point A plays the role of a common reference point for the resource block grid and is obtained as follows.

[0113] -OffsetToPointA for the primary cell (PCell) downlink represents the frequency offset between point A and the lowest subcarrier of the lowest resource block overlapping with the SS / PBCH block used by the terminal for initial cell selection. It is expressed in resource blocks, assuming that the subcarrier spacing for FR1 is 15kHz and the subcarrier spacing for FR2 is 60kHz.

[0114] -absoluteFrequencyPointA represents the frequency location of point A, as expressed in absolute radio frequency channel number (ARFCN).

[0115] For subcarrier spacing configuration μ, the common resource blocks are numbered from 0 upwards in the frequency domain. The center of subcarrier 0 of common resource block 0 for subcarrier spacing configuration μ is the same as "point A". Number of common resource blocks for subcarrier spacing configuration μ in the frequency domain The relationship between and resource element (k, l) is given by the following formula 1.

[0116] [Formula 1]

[0117]

[0118] In equation 1, k is defined relative to point A, so that k=0 corresponds to a subcarrier centered at point A. Physical resource blocks are spaced from 0 to 1 in a bandwidth part (BWP). where i is the number of the BWP. Physical resource block n in BWP i PRB and public resource block n CRB The relationship between is given by the following formula 2.

[0119] [Formula 2]

[0120]

[0121] is the common resource block where the BWP starts relative to common resource block 0.

[0122] Figure 5 The physical resource blocks in the wireless communication system to which the present disclosure can be applied are illustrated. Figure 6 The following illustrates a time slot structure in a wireless communication system to which the present disclosure can be applied.

[0123] refer to Figure 5 and Figure 6 , a slot includes a plurality of symbols in the time domain. For example, for a normal CP, a slot includes 7 symbols, but for an extended CP, a slot includes 6 symbols.

[0124] A carrier includes multiple subcarriers in the frequency domain. A resource block (RB) is defined as multiple (e.g., 12) consecutive subcarriers in the frequency domain. A bandwidth part (BWP) is defined as multiple consecutive (physical) resource blocks in the frequency domain and may correspond to a parameter set (e.g., SCS, CP length, etc.). A carrier may include up to N (e.g., 5) BWPs. Data communication may be performed through an activated BWP, and only one BWP may be activated for one terminal. In a resource grid, each element is called a resource element (RE) and may map a complex symbol.

[0125] In the NR system, each component carrier (CC) can support up to 400MHz. If the terminal working in such a wideband CC always operates with the radio frequency (FR) chip for the entire CC turned on, the terminal battery consumption may increase. Alternatively, when considering several application scenarios operating in a wideband CC (e.g., eMBB, URLLC, Mmtc, V2X, etc.), different parameter sets (e.g., subcarrier spacing, etc.) can be supported in each frequency band in the corresponding CC. Alternatively, each terminal may have a different maximum bandwidth capability. In this regard, the base station may instruct the terminal to operate only in part of the bandwidth instead of the total bandwidth of the wideband CC, and for convenience, the corresponding part of the bandwidth is defined as a bandwidth part (BWP). BWP can be configured with continuous RBs on the frequency axis and may correspond to a parameter set (e.g., subcarrier spacing, CP length, slot / microslot duration).

[0126] At the same time, even in one CC configured for the terminal, the base station can configure multiple BWPs. For example, a BWP occupying a relatively small frequency domain can be configured in the PDCCH monitoring time slot, and the PDSCH indicated by the PDCCH can be scheduled in a larger BWP. Alternatively, when the UE is congested in a specific BWP, some terminals can be configured with another BWP for load balancing. Alternatively, considering the frequency domain inter-cell interference elimination between adjacent cells, etc., some middle spectrums of the entire bandwidth can be excluded, and BWPs on two edges can be configured in the same time slot. In other words, the base station can configure at least one DL / UL BWP for a terminal associated with a broadband CC. The base station can activate at least one DL / UL BWP in the configured DL / UL BWP at a specific time (through L1 signaling or MAC control unit (CE) or RRC signaling, etc.). In addition, the base station can indicate switching to another configured DL / UL BWP (through L1 signaling or MAC CE or RRC signaling, etc.). Alternatively, based on a timer, when the timer value expires, it can switch to the determined DL / UL BWP. Here, the activated DL / UL BWP is defined as the active DL / UL BWP. However, when the terminal performs the initial access process or has not yet established an RRC connection, the configuration of the DL / UL BWP may not be received, so the DL / UL BWP assumed by the terminal in this case is defined as the initial active DL / UL BWP.

[0127] Figure 7 Physical channels used in a wireless communication system to which the present disclosure can be applied and a general signal transmission and reception method using the physical channels are illustrated.

[0128] In a wireless communication system, a terminal receives information from a base station via a downlink, and a terminal sends information to a base station via an uplink. The information sent and received by the base station and the terminal includes data and various control information, and there are various physical channels according to the type / purpose of the information they send and receive.

[0129] When the terminal is turned on or newly enters a cell, the terminal performs an initial cell search, which includes synchronization with a base station (S701). To this end, the terminal can synchronize with the base station by receiving a primary synchronization signal (PSS) and a secondary synchronization signal (SSS) from the base station, and obtain information such as a cell identifier (ID). Next, the terminal can obtain broadcast information in the cell by receiving a physical broadcast channel (PBCH) from the base station. At the same time, the terminal can check the downlink channel state by receiving a downlink reference signal (DL RS) in the initial cell search step.

[0130] The terminal that has completed the initial cell search can obtain more detailed system information by receiving a physical downlink control channel (PDCCH) and a physical downlink shared channel (PDSCH) according to information carried in the PDCCH (S702).

[0131] Meanwhile, if the terminal accesses the base station for the first time or does not have radio resources for signal transmission, the terminal may perform a random access procedure (RACH) on the base station (S703 to S706). To this end, the terminal may send a specific sequence as a preamble through a physical random access channel (PRACH) (S703 and S705), and receive a response message to the preamble through a PDCCH and a corresponding PDSCH (S704 and S706). In the case of a contention-based RACH, a contention resolution process may be additionally performed.

[0132] The terminal that has performed the above process may then perform PDCCH / PDSCH reception (S707) and physical uplink shared channel (PUSCH) / physical uplink control channel (PUCCH) transmission (S708) as a general uplink / downlink signal transmission process. Specifically, the terminal receives downlink control information (DCI) through PDCCH. Here, DCI includes control information such as resource allocation information for the terminal, and has different formats depending on its purpose of use.

[0133] At the same time, the control information sent by the terminal to the base station through the uplink or received by the terminal from the base station includes downlink / uplink confirmation / non-confirmation (ACK / NACK) signal, channel quality indicator (CQI), precoding matrix indicator (PMI), rank indicator (RI), etc. For the 3GPP LTE system, the terminal can send the above-mentioned CQI / PMI / RI and other control information through PUSCH and / or PUCCH.

[0134] SSB (Synchronization Signal Block) transmission and related operations

[0135] Figure 8 The structure of an SSB (Synchronization Signal and Broadcast Channel Block) applicable to the present disclosure is illustrated. Figure 8 The SSB structure is illustrated. The terminal can perform cell search, system information acquisition, beam alignment for initial access, DL measurement, etc. based on the SSB. The SSB is used interchangeably with the SS / PBCH (Synchronization Signal / Physical Broadcast Channel) block.

[0136] Reference Figure 8, SSB consists of PSS, SSS and PBCH. SSB consists of 4 consecutive OFDM symbols, and PSS, PBCH, SSS / PBCH and PBCH are sent for each OFDM symbol. PSS and SSS each consist of 1 OFDM symbol and 127 subcarriers, and PBCH consists of 3 OFDM symbols and 576 subcarriers. Polarization coding and QPSK (quadrature phase shift keying) are applied to PBCH. PBCH consists of data RE and DMRS (demodulation reference signal) RE for each OFDM symbol. Each RB has 3 DMRS REs, and there are 3 data REs between DMRS REs.

[0137] Community Search

[0138] Cell search refers to the process by which a terminal acquires time / frequency synchronization of a cell and detects the cell ID (identifier) ​​of the cell (e.g., physical layer cell ID, PCID). PSS is used to detect a cell ID within a cell ID group, and SSS is used to detect a cell ID group. PBCH is used for SSB (time) index detection and half-frame detection.

[0139] The cell search process of the terminal can be summarized as shown in the following [Table 5].

[0140] [Table 5]

[0141]

[0142] There are 336 cell ID groups, and each cell ID group has 3 cell IDs. There are 1008 cell IDs in total, and the cell ID can be defined by [Formula 3].

[0143] [Formula 3]

[0144] in, and

[0145] in, represents the cell ID (e.g., PCID), represents a cell ID group and is provided / obtained through SSS, Indicates a cell ID within a cell ID group and is provided / obtained through the PSS.

[0146] PSS sequence d PSS (n) can be defined as satisfying [Equation 4].

[0147] [Formula 4]

[0148] d PSS (n) = 1-2x(m)

[0149]

[0150] Where 0≤n<127, x(i+7)=(x(i+4)+x(i))mod 2, and

[0151] [x(6) x(5) x(4) x(3) x(2) x(1) x(0)]=[1 1 1 0 1 1 0].

[0152] SSS sequence d SSS (n) can be defined as satisfying [Equation 5].

[0153] [Formula 5]

[0154] d SSS (n)=[1-2x0((n+m0)mod 127)][1-2x1((n+m1)mod 127)]

[0155]

[0156] Among them, 0≤n<127, x0(i+7)=(x0(i+4)+x0(i))mod2, x1(i+7)=(x1(i+1)+x1(i))mod2, [x0(6) x0(5) x0(4) x0(3) x0(2) x0(1) x0(0)]=[0 0 0 0 0 0 1] Merger date [x1(6) x1(5) x1(4) x1(3) x1(2) x1(1) x1(0)]=[0 0 0 0 0 0 1].

[0157] Fig. 9 The transmission of SSB applicable to the present disclosure is illustrated. The SSB is transmitted periodically according to the SSB period. The SSB basic period assumed by the terminal during the initial cell search is defined as 20ms. After cell access, the network (e.g., base station) can set the SSB to one of {5ms, 10ms, 20ms, 40ms, 80ms, 160ms}. The SSB burst set is configured at the beginning of the SSB period. The SSB burst set consists of a 5ms time window (i.e., half a frame), and the SSB can be transmitted up to L times within the SSB burst set. Depending on the frequency band of the carrier, the maximum number L of SSB transmissions can be given as follows. A time slot includes at most two SSBs.

[0158] - For the frequency range up to 3 GHz, L = 4

[0159] - For the frequency range of 3 GHz to 6 GHz, L = 8

[0160] - For the frequency range of 6 GHz to 52.6 GHz, L = 64

[0161] The temporal position of a candidate SSB within an SSB burst set may be defined according to the SCS as follows. The temporal position of a candidate SSB is indexed in temporal order from 0 to L-1 within an SSB burst set (ie, half-frame) (SSB index). Candidate SSB and SSB candidate may be used interchangeably in the specification.

[0162] - Case A - 15kHz SCS: The index of the starting symbol of the candidate SSB is given as {2, 8} + 14*n.

[0163] - For operation without shared spectrum channel access (e.g. L-band, LCell): If the carrier frequency is 3 GHz z or less, then n = 0, 1. If the carrier frequency is 3 GHz to 6 GHz, then n = 0, 1, 2, 3.

[0164] - For operation with shared spectrum channel access (eg, U-band, UCell): n=0, 1, 2, 3, 4.

[0165] - Case B - 30kHz SCS: The index of the starting symbol of the candidate SSB is given as {4, 8, 16, 20} + 28*n. If the carrier frequency is 3 GHz or less, n = 0. If the carrier frequency is 3 GHz to 6 GHz, n = 0, 1.

[0166] - Case C - 30kHz SCS: The index of the starting symbol of the candidate SSB is given as {2, 8}+14*n.

[0167] - For operation without shared spectrum channel access: (1) For paired spectrum operation, when the carrier frequency is 3 GHz or less, n = 0, 1. When the carrier frequency is within FR1 and greater than 3 GHz, n = 0, 1, 2, 3. (2) For non-paired spectrum operation, when the carrier frequency is 2.4 GHz or less, n = 0, 1. When the carrier frequency is within FR1 and greater than 2.4 GHz, n = 0, 1, 2, 3.

[0168] - For operation without shared spectrum channel access: n=0, 1, 2, 3, 4, 6, 7, 8, 9.

[0169] - Case D - 120kHz SCS: The index of the starting symbol of the candidate SSB is given as {4, 8, 16, 20} + 28*n. For carrier frequencies in FR2, n = 0, 1, 2, 3, 5, 6, 7, 8, 10, 11, 12, 13, 15, 16, 17, 18.

[0170] - Case E - 240kHz SCS: The indices of the starting symbols of the candidate SSBs are given as {8, 12, 16, 20, 32, 36, 40, 44} + 56*n. For carrier frequencies within FR2, n = 0, 1, 2, 3, 5, 6, 7, 8.

[0171] For operation with shared spectrum channel access, in the case of shared spectrum channel access operation, the terminal assumes that the SSB transmission within the half frame is within the discovery burst transmission window starting from the first symbol of the first time slot within the half frame. The discovery burst transmission window period for each serving cell may be provided to the terminal. If the discovery burst transmission window period is not provided, the terminal regards the discovery burst transmission window period as a half frame. For each serving cell, the terminal assumes that the repetition period of the discovery burst transmission window is the same as the repetition period of the half frame used for SSB reception. The terminal may assume that among the SSBs of the serving cell, the discovery burst transmission window has the same repetition period within the same discovery burst transmission window or across different discovery burst transmission windows. The SSB of the value is in a QCL (quasi co-location) relationship. represents the DM-RS sequence index of the PBCH of the SSB, and (i) provided by ssbPositionQCL-Relationship, or (ii) if ssbPositionQCL-Relationship is not provided, it can be obtained from the MIB (Master Information Block) of the SSB based on [Table 6].

[0172] [Table 6]

[0173]

[0174] ssbSubcarrierSpacingCommon represents the SCS of the RMSI used only for "operation without shared spectrum". The terminal assumes that the number of SSBs sent on the serving cell within the discovery burst transmission window is no greater than The terminal can be based on or to determine the SSB index. Here, i represents the candidate SSB index. Accordingly, more than one candidate SSB may correspond to one SSB index. Candidate SSBs corresponding to the same SSB index are quasi-co-located. Fig.10 Examples of SSB candidate positions applicable to the present disclosure are illustrated. Fig.10The case where Q is 4 and ssb-PositionsInBurst is set to "10100000" is illustrated. In this case, only SSBs with SSB (SS / PBCH block) index #0 / #2 can be transmitted. ssb-PositionsInBurst and Q can be used to provide a rate matching mode within a DRS (discovery reference signal) transmission window (or discovery burst transmission window). For example, the terminal can perform rate matching for all SSB candidate position indices that are consistent with the actual transmitted SSB index QCL provided by ssb-PositionsInBurst. Fig.10 In the example, the terminal can perform rate matching on the time / frequency resources of SSB candidate position index 0 / 2 / 4 / 6 / 8 / 10 / 12 / 14 / 16 / 18. Therefore, when receiving a PDSCH scheduled by a PDCCH scrambled with CRC by C-RNTI, MCS-C-RNTI, CS-RNTI, RA-RNTI, MsbB-RNTI, P-RNTI, TC-RNTI (or a PDSCH with SPS (or with CRC) scrambled by SI-RNTI and the system information indicator (i.e., DCI) in the PDCCH is set to 1), if the PDSCH resource allocation overlaps with the PRB including the SSB transmission resources (e.g., SS / PBCH block candidate position index 0 / 2 / 4 / 6 / 8 / 10 / 12 / 14 / 16 / 18), the terminal can assume SSB transmission according to ssb-PositionsInBurst. That is, the terminal may assume that the PRB including the SSB transmission resources in the OFDM symbol in which the SSB is transmitted is unavailable for the PDSCH (ie, not mapped).

[0175] Fig.11 An example of downlink time synchronization information applicable to the present disclosure is illustrated. Fig.11 The terminal obtains information about DL time synchronization. The terminal can obtain DL synchronization by detecting SSB. The terminal can identify the structure of the SSB burst set based on the detected SSB index, and can detect the symbol / time slot / half-frame boundary accordingly. The SFN information and half-frame indication information can be used to identify the number of frames / half-frames to which the detected SSB belongs.

[0176] Specifically, the terminal can obtain 10-bit SFN (system frame number) information (s0 to s9) from the PBCH. Among the 10-bit SFN information, 6 bits are obtained from the MIB (master information block) and the remaining 4 bits are obtained from the PBCH TB (transport block).

[0177] Next, the terminal can obtain 1 bit of half-frame indication information (c0). When the carrier frequency is 3 GHz or less, the half-frame indication information can be implicitly signaled using PBCH DMRS. PBCH DMRS indicates 3 bits of information by using one of 8 PBCH DMRS sequences. Therefore, in the case of L=4, among the 3 bits that can be indicated using 8 PBCH DMRS sequences, the remaining 1 bit after indicating the SSB index can be used to indicate the half-frame.

[0178] Finally, the terminal can obtain the SSB index based on the DMRS sequence and the PBCH payload. The SSB candidates are indexed in time order from 0 to L-1 within the SSB burst set (i.e., half-frame). When L=8 or 64, 8 different PBCH DMRS sequences can be used to indicate the 3 bits (b0 to b2) of the least significant bit (LSB) of the SSB index. When L=64, the 3 bits (b3 to b5) of the most significant bit (MSB) of the SSB index are indicated via PBCH. When L=2, 4 different PBCH DMRS sequences can be used to indicate the 2 bits (b0, b1) of the LSB of the SSB index. When L=4, among the 3 bits that can be indicated using 8 PBCH DMRS sequences, the remaining 1 bit after indicating the SSB index can be used to indicate the half frame (b2).

[0179] Specific embodiments of the present disclosure

[0180] The present disclosure describes a technology for turning on / off synchronization signals and broadcast channel signals in a wireless communication system. Specifically, the present disclosure describes an implementation for dynamically turning on / off synchronization signals / physical broadcast channel blocks (SSBs) to save energy of base stations in a wireless communication system and performing various operations based thereon.

[0181] Energy saving of base stations can contribute to building environmentally friendly networks by reducing carbon emissions and reducing operating expenditures (OPEX) of players in the communications industry. Therefore, energy saving of base stations is considered to be crucial in wireless communication systems including 3GPP. In particular, due to the introduction of 5G, which requires high transmission rates, base stations should be equipped with more antennas and provide services through wider bandwidths and frequency bands. Therefore, research results showing that the energy cost of base stations reaches 20% of the total OPEX were published. As interest in energy saving of base stations increases, a new SI (research project) called "Network Energy Saving Research" was approved in 3GPP NR Release 18.

[0182] Specifically, from the perspective of transmission and reception of base stations, enhancement techniques are being considered to improve energy saving capabilities, namely network energy saving (NES). For example, the method is considered to utilize potential assistance / feedback from user equipment (UE) and potential UE assistance information to achieve dynamic and / or semi-static efficient operation in one or more network energy saving techniques in time, frequency, space and power domains, and to achieve finer-grained transmission and / or reception adaptation.

[0183] The base station can operate the technology to control the opening / closing for a certain duration on the time axis for the purpose of NES, control the transmission / reception resources used for UE common or UE specific signals / channels, change the amount of frequency axis resources, control the transmission power, or open / close the antenna port or transmit reception point (TRP) in the spatial domain. Hereinafter, in the present disclosure, the state of applying the above-mentioned NES related technology (hereinafter referred to as NES technology) is referred to as NES mode or NES state. Hereinafter, in the present disclosure, according to method 1, the base station can notify the terminal which (which) NES technology is applied for each NES technology or NES technology group. Alternatively, according to method 2, the base station can pre-configure the corresponding NES technology or NES technology group through the code point of a specific indicator (for example, an indicator indicated via DCI or MAC CE, etc., an indicator set by high-level signaling).

[0184] For method 1, if at least one NES technology is applied, the terminal can define the state as NES mode or NES state. Alternatively, depending on which NES technology is applied, the terminal can define different NES modes or different NES states to be applied. For method 2, the terminal can define the state according to the NES technology associated to the indicator. For example, in the case where a 1-bit indicator is used, the NES technology corresponding to "0" is not associated, and one or more NES technologies corresponding to "1" are associated, if an indicator with a value of "1" is received, the terminal can define the state as NES mode or NES state. As another example, when a 2-bit indicator is used, and the NES technology corresponding to "00" is not associated, one or more NES technology_A is associated to "01", one or more NES technology_B is associated to "10", and one or more NES technology_C is associated to "11", and an indicator whose code point is not "00" is received, the terminal can define the state as NES mode or NES state. In this case, the terminal can determine whether it is an NES state or which NES state it is by defining NES state #1 when receiving "01", defining NES state #2 when receiving "10", and defining NES state #3 when receiving "11".

[0185] The present disclosure will propose various implementations for saving energy of a base station by turning on / off SSB and for receiving random access, broadcast signals and / or broadcast channels according to the SSB on / off situation.

[0186] Even in the case where there is no actual data to be sent from the base station, it is necessary to send SSBs according to a preset period in consideration of the terminals that will reside on the cell or the terminals that will perform RRM measurements. However, in the case where there are no terminals accessing the cell, or the number of terminals accessing the cell is very small, or there are no terminals in a specific beam direction, or specific antenna elements should be turned off to save energy, the base station can save energy by not performing transmission on some SSBs. Therefore, the present disclosure proposes a technology for signaling the turning on / off of SSBs more dynamically than before, as well as an implementation of an operating method of a terminal in a random access process, a broadcast signal reception process, and / or a broadcast channel reception process in the case of dynamic turning on / off of SSBs.

[0187] Fig.12 An example of a process for receiving an SSB in a wireless communication system according to an embodiment of the present disclosure is illustrated. Fig.12 The operation method of the terminal is illustrated.

[0188] Reference Fig.12 In step S1201, the terminal receives information indicating the turning on / off of the SSB. The information indicating the turning on / off of the SSB may be defined in various ways. According to various embodiments, the information indicating the turning on / off of the SSB may be received via at least one of DCI, MAC CE, broadcast data, multicast data, RRC message, or system information. In addition, according to various embodiments, the information indicating the turning on / off of the SSB may be in the form of an index indicating at least one SSB to be turned on and / or at least one SSB to be turned off, or may be in the form of indicating one of the available candidate modes. Here, the index may correspond to one SSB or may correspond to multiple SSBs.

[0189] In step S1203, the terminal identifies at least one SSB in a closed state among the SSBs. That is, the terminal identifies the transmission mode of the SSB. Based on the information indicating the on / off of the SSB, the terminal can determine at which time to send the SSB and / or at which time not to send the SSB. Therefore, the terminal can attempt to receive and detect the SSB only when the SSB is turned on.

[0190] In step S1205, the terminal receives at least one SSB. The terminal identifies the timing when the SSB is turned on according to the identified transmission mode, and attempts to receive the SSB at each of the identified timings. At this time, at least one SSB can be detected. When at least one SSB in the SSB is received, the terminal can perform an operation based on SSB detection.

[0191] Fig.13 An example of a process for transmitting SSB in a wireless communication system according to an embodiment of the present disclosure is illustrated. Fig.13 An operation method of a base station is illustrated.

[0192] Reference Fig.13 In step S1301, the base station identifies at least one SSB controlled to be in a closed state among the SSBs. That is, the base station identifies the transmission mode of the SSB. The base station can determine at which time to send the SSB and / or at which time not to send the SSB. At this time, the ratio of at least one SSB to be closed can be determined according to the energy saving target.

[0193] In step S1303, the base station sends information indicating the turning on / off of the SSB. The information indicating the turning on / off of the SSB may be defined in various ways. According to various embodiments, the information indicating the turning on / off of the SSB may be received via at least one of DCI, MAC CE, broadcast data, multicast data, RRC message, or system information. In addition, according to various embodiments, the information indicating turning the SSB on / off may be in the form of an index indicating at least one SSB to be turned on and / or at least one SSB to be turned off, or may be in the form of indicating one of the available candidate modes. Here, the index may correspond to one SSB or may correspond to multiple SSBs.

[0194] In step S1305, the base station transmits the SSB. The base station may identify the timing when the SSB is turned on according to the identified transmission mode, and transmit the SSB at each of the identified timings.

[0195] [Implementation #1] Method for signaling SSB on / off

[0196] Fig.14 An example of a process for receiving SSB on / off information in a bitmap form in a wireless communication system according to an embodiment of the present disclosure is illustrated. Fig.14 The operation method of the terminal is illustrated.

[0197] Reference Fig.14In step S1401, the terminal receives a bitmap related to the SSB. For example, the terminal may receive a bitmap related to the SSB through DCI, PDSCH, MAC CE and / or high-layer signaling, where the bitmap indicates on / off information for each SSB index or each SSB index group.

[0198] In step S1403, the terminal identifies the on / off information of each SSB index based on the bitmap related to the SSB. The terminal may identify at least one SSB index or SSB index group mapped to each bit included in the bitmap related to the SSB based on a predefined mapping rule, and identify the on / off state of each SSB index based on the value of each bit. According to one embodiment, the predefined mapping rule is as described in alternative embodiments 1-1 to 1-3. According to one embodiment, multiple SSB candidate indexes may be associated with one SSB index.

[0199] In step S1405, the terminal controls the application time of the on / off information of each SSB index. According to one embodiment, the terminal may determine the application time of the on / off information of each SSB index after a specified time period (e.g., X ms) or a specified time slot (e.g., Y time slot) based on the time point of sending the ACK information for the bitmap associated with the SSB. According to one embodiment, the terminal may receive information about the application time of the corresponding information (e.g., a relative time offset or an absolute time point) together with the bitmap associated with the SSB. The terminal may apply the on / off information of each SSB index at the identified information application time point. In this way, the terminal applies the on / off information of each SSB index at the application time of the identified information to minimize the mismatch problem with the base station. However, according to various embodiments, instead of controlling the application time of the on / off information by the SSB index, a method of increasing the number of transmissions of the base station for the bitmap associated with the SSB may also be used. Alternatively, a method of controlling the application time of the on / off information of each SSB index and a method of increasing the number of transmissions of the bitmap associated with the SSB at the base station may be used simultaneously.

[0200] SSB on / off signaling will be described in more detail as follows.

[0201] Whether the SSB index is sent may be signaled via a bitmap for each SSB index or each group of indexes (e.g., ssb-PositionsInBurst or ServingCellConfigCommon in SIB1). Specifically, the terminal may receive DCI related to system information, obtain allocation information for receiving system information based on the DCI, receive system information based on the allocation information, and obtain information related to the SSB included in the system information. The following [Table 7] illustrates the configuration of ServingCellConfigCommon extracted from TS 38.331, and [Table 8] illustrates the definition of parameters included in ServingCellConfigCommon.

[0202] [Table 7]

[0203]

[0204] [Table 8]

[0205]

[0206] The following Table 9 illustrates the configuration of ServingCellConfigCommonSIB extracted from TS 38.331, and Table 10 illustrates the definition of parameters included in ServingCellConfigCommonSIB.

[0207] [Table 9]

[0208]

[0209] [Table 10]

[0210]

[0211] The bitmap information as described above may be transmitted via a group-common DCI, a MAC CE and / or a broadcast DCI included in a multicast / broadcast PDSCH, and / or a PDSCH scheduled via a broadcast DCI, etc. The group-common DCI may include a DCI transmitted via a search space (SS) set configured in a UE-common and / or group-common manner, and / or a DCI scrambled by an RNTI allocated in a UE-common and / or group-common manner. The MAC CE and / or the broadcast DCI included in the multicast / broadcast PDSCH may include a DCI for scheduling a PDSCH carrying system information, paging, or multicast / broadcast data.

[0212] As described above, when the on / off information of each SSB index is received via DCI, PDSCH and / or MAC CE, even if the on / off information of each SSB index is received via cell-common RRC signaling (such as the existing SIB1 and / or ServingCellConfigCommon), the terminal can ignore and overwrite the information received via the cell-common RRC signaling.

[0213] Specifically, the bit position of the DCI or MAC CE corresponding to each SSB index or SSB index group may be predefined or set.

[0214] According to alternative 1-1, as many bits as the maximum number of SSB indexes defined for each frequency domain may be arranged in the DCI or MAC CE. In this case, the kth bit may correspond to the on / off information of the kth SSB index. The maximum number of SSB indexes may be the L_max value defined in the TS 38.213 specification. For example, the maximum number of SSB indexes may be L_max=4 in FR1 of 3 GHz or less, L_max=8 in FR1 of 3 GHz or greater, and L_max=64 in FR2.

[0215] According to alternative scheme 1-2, a number of bits smaller than the maximum number of SSB indexes defined for each frequency domain may be provided in the DCI or MAC CE, and the information corresponding to each bit may be determined by a predefined rule. For example, in FR2, eight bits may be provided in the DCI or MAC CE, and the SSB indexes corresponding to the bits may be grouped in 8 order, and each index group may be mapped to each bit. For example, index group #1 including SSB indexes 0 to 7 may be mapped to the first bit among the bits provided in the DCI or MAC CE, and index group #2 including SSB indexes 8 to 15 may be mapped to the second bit among the bits provided in the DCI or MAC CE. Therefore, the on / off information of each SSB index or the on / off information of each SSB index group may be indicated based on the mapping as described above.

[0216] According to alternative schemes 1-3, a mapping relationship between one SSB index or multiple SSB indexes corresponding to each bit of the DCI or MAC CE can be set. For example, the relationship that the SSB index #k corresponds to the nth bit can be preset, and the on / off information of the SSB index #k can be indicated by the nth bit. For another example, the following relationship can be preset: SSB indexes #n to #n+k correspond to the mth bit, and the on / off information of the SSB indexes #n to #n+k can be indicated once by the mth bit. For another example, a terminal that has received information that K bits are allocated to the DCI or MAC CE can identify the mapping relationship between a total of L_max SSB indexes and K bits based on the K value and predefined rules. For example, a rule can be defined in which an equal number of SSB indexes are sequentially mapped to each bit. In this case, if L_max=8 and the K value is 2, the terminal can recognize that the first bit of the two bits corresponds to SSB indexes 0 to 3, and the second bit of the two bits corresponds to SSB indexes 4 to 7.

[0217] In the above embodiment, the population of SSB indexes indicating on / off information via DCI or MAC CE may be L_max, or the number of SSB indexes transmitted via the ssb-PositionsInBurst parameter. Here, the SSB index transmitted via the ssb-PositionsInBurst parameter may be referred to as "N_SSB". For example, if the 8-bit bitmap information in FR1 is "11110000", N_SSB may mean 4.

[0218] According to alternative 1-1, as many bits as N_SSB may be provided in the DCI or MAC CE. In this case, the k-th bit may correspond to the on / off information of the k-th SSB index transmitted in the ssb-PositionsInBurst parameter.

[0219] According to alternative scheme 1-2, when the 8-bit bitmap information is "11001100" in FR1, N_SSB is 4. At this time, a bit smaller than N_SSB (for example, 2 bits) can be provided in DCI or MAC CE. At this time, the SSB index indicating transmission can be grouped in 2 order and then mapped to the corresponding bit. That is, the bitmap information " 11 001100" indicates that the transmitted SSB indexes 0 and 1 can be mapped to the first of the two bits provided in the DCI or MAC CE and are represented by the bitmap information '1100 1100' indicates that the transmitted SSB indexes 4 and 5 may be associated with the second bit of the two bits provided in the DCI or MAC CE, and on / off information of the corresponding SSB index may be indicated based on the association.

[0220] According to alternative schemes 1-3, a terminal that has received information that K bits are allocated to DCI or MAC CE can identify the mapping relationship between the N_SSB SSB index and the K bits based on the K value and predefined rules. For example, a rule in which an equal number of SSB indexes are sequentially mapped to each bit can be predefined. At this time, when in FR1, the 8-bit bitmap information is indicated as "11101110", so that N_SSB is 6 and the K value is 2, the terminal can recognize that the first of the two bits is mapped to SSB indexes 0 to 2, and the second of the two bits is mapped to SSB indexes 4 to 6.

[0221] According to one embodiment, the shutdown information of a specific SSB index may be signaled through the power information of the SSB. If the transmission power value of the SSB of a specific index is signaled as a specific value through DCI and / or PDSCH, etc., the terminal may interpret that the corresponding SSB is not transmitted. The specific value may be the minimum value of the set value range or a reserved state.

[0222] According to one embodiment, multiple SSB candidate indexes may be associated with one SSB index. Specifically, the SSB index may be associated with multiple SSB candidate indexes and a The modulus operation of the value is determined as shown in [Table 11] below. In the case of using bitmap information to turn on / off a specific SSB index according to the above embodiment, the turn on / off information can be applied to all SSB candidate indexes corresponding to the bitmap information in a specific frequency band (e.g., an unlicensed frequency band).

[0223] at the same time, The value indicates how much the SSB candidate index is rotated by the SSB cycle. This can be signaled via DCI, PDSCH and / or MAC CE as described above. When received via DCI, PDSCH and / or MAC CE When the value is ServingCellConfig or ServingCellConfigCommon, the terminal may ignore and override the received value via the existing master information block (MIB) and / or cell common RRC signaling (such as ServingCellConfig or ServingCellConfigCommon). value.

[0224] According to one embodiment, The value may be used for specific frequency band operations, such as unlicensed frequency band operations. Here, unlicensed frequency band operations may be understood as operations with shared spectrum channel access. However, the above embodiments are not limited to unlicensed frequency bands. For example, the above embodiments may be applied to a case where multiple SSB candidate indexes are associated with one SSB index, and / or a case where SSBs are reused regardless of the frequency band.

[0225] The following [Table 11] is an excerpt from Section 4.1 of TS 38.213.

[0226] [Table 11]

[0227]

[0228]

[0229] For the SSB index to which the on / off information is applied by the above method, if the PDSCH overlaps with the SSB, the terminal may assume that the PDSCH is not mapped to the PRB including the SSB, or determine that the SSB is not available for the PDSCH. Here, if the SSB candidate index is used, the SSB index may be understood as including all SSB candidate indexes associated with the SSB index.

[0230] According to various embodiments, the on / off information of the SSB may be updated. In this case, a mismatch problem may occur between the base station and the terminal because the terminal loses the update information of the SSB. In order to minimize the mismatch problem, the application time of the SSB information may be controlled, the number of times the SSB is sent may be increased, or the application time of the SSB information may be signaled together with the SSB. For example, the application time of the SSB information may be determined as X ms or Y time slots after the time point when the terminal sends an ACK (acknowledgement) for the on / off information of the SSB. Alternatively, the base station may send the on / off information of the SSB multiple times. When the on / off information of the SSB is sent multiple times, stability may be improved. Alternatively, the application time of the information may be signaled together with a container containing the on / off information of the SSB. For example, the application time of the information may be set as a relative time offset from the time point of sending the container, or as an absolute time such as SFN Z.

[0231] According to various embodiments, certain SSB indexes may be considered as high priority so that the on / off information may not be dynamically updated. An SSB index with a high priority may be predefined or set by high-level signaling. For example, high-level signaling may include cell-specific RRC signaling or UE-specific RRC signaling. When the on / off information of each SSB index is configured as a bitmap via DCI, PDSCH, and / or MAC CE, bits corresponding to SSB indexes with a high priority may not be allocated. Here, an SSB index with a high priority may mean an SSB index that is not sent via the ssb-PositionsInBurst parameter setting.

[0232] The implementation method of dynamically changing the on / off of SSB as described in implementation method #1 can be applied only to specific situations and / or specific time periods. For example, it can be applied when an NES state is indicated, when a specific DRX (discontinuous reception) configuration is indicated or applied, when switching to a specific BWP, or during a configured DRX active time or outside a DRX active time. However, the listed situations and / or time periods are merely examples to help understand, and the situations and / or time periods in which the implementation method of dynamically changing the on / off of SSB is applied are not limited to the above examples. In the present disclosure, the DRX configuration can be a DRX configuration set for idle / inactive terminals, a C-DRX configuration set for connected terminals, or a configuration of a DTX and / or DRX mode of a base station in a cell-specific or UE group-common manner (hereinafter referred to as "cell DTX / DRX"). In this case, the DRX active time can represent the time period during which the onDurationtimer and / or inactivitytimer operate, or the time during which the terminal should remain awake to send and / or receive.

[0233] [Implementation #2] Random Access Procedure

[0234] Fig.15 An example of a process for transmitting a RACH preamble based on SSB on / off information in a wireless communication system according to an embodiment of the present disclosure is illustrated. Fig.15 The operation method of the terminal is illustrated.

[0235] Reference Fig.15 In step S1501, the terminal identifies the on / off mode of the SSB. The on / off mode of the SSB can be identified according to the above various embodiments. Specifically, the terminal can identify the on / off mode of the SSB based on the signaling from the base station.

[0236] In step S1503, the terminal determines the mapping between the SSB and the RO (RACH opportunity). Each of the SSBs sent from the base station is associated with at least one RO, and the terminal sends a RACH preamble in the RO associated with the detected SSB. According to various embodiments, since the index of the transmitted SSB can be changed by controlling the on / off mode of the SSB, the terminal can reset the mapping relationship between at least one SSB in the on state and the RO based on the on / off mode of the SSB. In order to reset the mapping relationship between the SSB and the RO, according to one embodiment, the terminal may redefine the mapping with all ROs according to at least one SSB in the on state. That is, the terminal may sequentially map the remaining SSB indexes except for at least one SSB index in the off state to the RO. According to another embodiment, the terminal may map at least one RO associated with at least one SSB in the off state to another SSB in the on state.

[0237] In step S1505, the terminal sends a RACH preamble. Specifically, the terminal may detect the SSB, identify the RO associated with the detected SSB based on the mapping between the SSB and the RO, and send the RACH preamble in the identified RO.

[0238] As described above, SSB to RO mapping may be considered. As shown in the following [Table 12], according to the standard, SSB to RO mapping is performed based on ssb-PositionsInBurst information set via SIB1 or ServingCellConfigCommon, and an associated period and an associated mode period may be determined. [Table 12] illustrates TS38.213 Section 8.1.

[0239] [Table 12]

[0240]

[0241] As in the above-mentioned [Implementation #1], if the on / off information of a specific SSB index can be updated through DCI, PDSCH and / or MAC CE, it is necessary to consider the updated on / off information when performing SSB to RO mapping. The SSB to RB mapping method considering the updated on / off information may follow at least one of the following implementations.

[0242] According to alternative solution 2-1, the terminal can re-perform SSB to RO mapping using only the SSB index in the on state based on the updated on / off information of the SSB index. That is, the on / off information of [Table 12] can be updated based on the on / off information of [Implementation #1]. For example, the number of SSB indexes actually transmitted based on the ssb-PositionsInBurst information set via SIB1 or ServingCellConfigCommon is 4, and if one of the SSB indexes is turned off via DCI or PDSCH, as described in [Implementation #1], then

[0243] According to alternative scheme 2-2, the terminal maintains the SSB to RO mapping based on the ssb-PositionsInBurst information set via the existing SIB1 or ServingCellConfigCommon, and the RO corresponding to the SSB index in the off state or the corresponding preamble in the RO is considered invalid based on the updated on / off information. Alternatively, the terminal may not regard the RO or the corresponding preamble in the RO corresponding to the SSB index in the off state as invalid, but rather regard it as corresponding to the SSB index mapped near the RO or the corresponding preamble in the RO. For example, assume that RO#1 is associated with SSB index 1, and RO#2 is associated with SSB index 2. At this time, if SSB index 2 is set to the off state by DCI or PDSCH, the terminal may regard RO#2 as invalid, or may regard RO#2 as also associated with SSB index 1.

[0244] According to alternative scheme 2-3, when the SSB to RO mapping is re-executed by updating the on / off information of the SSB index as described in implementation 2-1, a problem may occur due to a mismatch in the corresponding information. To solve this problem, the terminal may maintain the association period and / or association mode period determined by the SSB to RO mapping based on the ssb-PositionsInBurst information set via SIB1 or ServingCellConfigCommon, and perform SSB to RO mapping. For example, if the association period or association mode period determined by the SSB to RO mapping based on the ssb-PositionsInBurst information set via SIB1 or ServingCellConfigCommon is 80 milliseconds, the terminal may reflect the updated on / off information of the SSB index within 80 milliseconds and re-execute the SSB to RO mapping using only the SSB index that is in the on state.

[0245] When applying the above alternative, the number of PRACH time slots can also be changed based on the number of SSB indexes in the on state. For example, if the number of PRACH time slots is reduced as much as the number of SSB indexes in the on state, the energy saving effect of the base station can be maximized. Specifically, N PRACH time slots can be set per frame through the RACH configuration in SIB1, and the K SSB indexes to be actually sent can be set. If K / 2 of the K SSB indexes are turned off as indicated by DCI, the number of PRACH time slots can also be reduced to N / 2 per frame. In this case, N / 2 time slots out of N PRACH time slots can be determined according to a preset configuration or predefined rules of the base station. For example, the predefined rules may include a rule that the first N / 2 time slots are considered valid among the N time slots in the frame, or a rule that one time slot is considered valid and the next time slot is considered invalid among two consecutive PRACH time slots.

[0246] In addition to SSB to RO mapping, the above alternatives can also be applied to SSB to PO (PUSCH timing). For example, the above alternatives 2-1 to 2-3 can be applied in a similar manner to the SSB to PO (PUSCH timing) mapping of the 2-step RACH process. In the case of 2-step RACH, the RACH preamble and msg-3 are sent as MSGA (message-A), for which PO and RO need to be selected. PO can be selected based on the selected RO and / or the selected RACH preamble. PO and RACH preamble have a mapping relationship. Specifically, the preamble index is listed in the following order: first according to the index within the PO, second according to the frequency axis position of the PO, and third according to the time axis position of the PO. PO is listed in the following manner: first according to the frequency axis position of the PO, second according to the DMRS resource index within the PO, and third according to the time axis position of the PO, and then the PO can be mapped to each other. In this way, since the RO is selected based on the SSB, the selection of the PO can be related to the on / off of the SSB.

[0247] Specifically, according to alternative schemes 2-4, the terminal can re-execute the SSB to PO mapping using only the SSB index in the on state based on the updated on / off information of the SSB index. For example, if the number of SSB indexes actually transmitted based on the signaling from the base station is 4, and one of the SSB indexes is signaled to be turned off via DCI or PDSCH as described in [Implementation #1], the terminal can re-execute the SSB to PO mapping based on these three SSB indexes.

[0248] According to alternative scheme 2-5, the terminal may maintain the existing SSB to PO mapping, and based on the updated on / off information, the PO corresponding to the SSB index in the off state or the corresponding preamble in the PO may be considered invalid. Alternatively, the terminal may not consider the PO or the corresponding preamble in the PO corresponding to the SSB index in the off state as invalid, but may consider them as corresponding to the SSB index or the corresponding preamble in the PO mapped near the PO. For example, assume that PO#1 is associated with SSB index 1, and PO#2 is associated with SSB index 2. In this case, if SSB index 2 is specified as the off state by DCI or PDSCH, the terminal may consider PO#2 invalid, or regard PO#2 as also associated with SSB index 1.

[0249] According to alternative scheme 2-6, when the SSB to PO mapping is re-executed by updating the on / off information of the SSB index as described in implementation mode 2-4, a problem may occur due to a mismatch in the information. To solve this problem, the terminal may maintain the association period and / or association mode period determined by the signaling-based SSB to PO mapping, and perform SSB to PO mapping. For example, when the association period or association mode period determined by the signaling-based SSB to PO mapping is 80 milliseconds, the terminal may reflect the updated on / off information of the SSB index within 80 milliseconds, and re-execute the SSB to PO mapping using only the SSB index in the on state.

[0250] Next, the random access procedure will be described in the case where a PRACH corresponding to a specific SSB index is sent and then the SSB index is turned off. For example, after the terminal sends a PRACH corresponding to a specific SSB index, the SSB index can be turned off in the same manner as described in [Implementation #1] above. In this case, the RACH procedure can be performed as follows.

[0251] Fig.16 An example of a procedure for performing a RACH procedure based on SSB on / off in a wireless communication system according to an embodiment of the present disclosure is illustrated. Fig.16 The operation method of the terminal is illustrated.

[0252] Reference Fig.16 In step S1601, the terminal receives an SSB with an index of 1. According to an embodiment, the terminal may detect an SSB with an index of 1 that is in an on state.

[0253] In step S1603, the terminal sends a RACH preamble to the base station. At this time, the terminal can send the RACH preamble to the base station in the RO corresponding to the SSB with an index of 1 in the on state.

[0254] In step S1605, the terminal receives SSB on / off information from the base station. According to the above various embodiments, the base station may send SSB on / off information to the terminal. At this time, in this embodiment, the SSB on / off information may indicate the closing of index 1.

[0255] In step S1607, the terminal performs a RACH process based on the SSB on / off information. That is, as the SSB index (e.g., index 1) associated with the RO used to send the RACH preamble is turned off, at least one parameter related to the RACH process may be changed. According to one embodiment, when the RAR is not received, the terminal may control the value of the power ramp counter and / or the PRACH retransmission counter. According to one embodiment, the terminal may terminate, maintain, or increase the random access response (RAR) window.

[0256] According to one embodiment, even if the RAR corresponding to the transmitted PRACH is not received, the terminal may not increase the power ramp counter and / or the PRACH retransmission counter value. Alternatively, the terminal may assume that the RACH process itself is not triggered / started from the perspective of terminal operation. This is because when the base station turns off the corresponding SSB index, not only the TX chain but also the RX chain in the corresponding beam direction may be deactivated, which may result in a situation where the corresponding PRACH fails to be received at the base station.

[0257] According to one embodiment, when the terminal receives information indicating that a specific SSB index is turned off after a PRACH corresponding to the specific SSB index is transmitted, the terminal may control the RAR window as in the following options:

[0258] Option A: The terminal may terminate the RAR window and attempt PRACH retransmission upon receiving information indicating that the corresponding SSB index is closed. That is, the terminal may recognize that the RAR corresponding to the transmitted PRACH will not be received, and may quickly terminate the RAR window, thereby minimizing the delay of the random access process.

[0259] Option B: The terminal may maintain the RAR window by considering that the on / off of the SSB is dynamically changed. That is, the terminal may maintain the RAR window until receiving information indicating that the SSB is turned on.

[0260] Option C: The terminal can increase the RAR window by X times by taking into account the dynamic changes of SSB on / off.

[0261] Depending on the frequency of turning on / off SSB, which of the above options is more efficient for the random access procedure may vary. Therefore, which of the above options can be set by the base station.

[0262] The above embodiment has been described with reference to PRACH transmission in a 4-step RACH procedure as an example. However, the above embodiment can be similarly applied to msgA transmission (ie, PRACH and PUSCH transmission) in a 2-step RACH procedure.

[0263] Specifically, according to one embodiment, even if the MSGB (message-B) corresponding to the PRACH and PUSCH sent according to the 2-step RACH is not received, the terminal may not increase the power ramp counter and / or the PRACH retransmission counter value. Alternatively, the terminal may assume that the RACH process itself is not triggered / started from the perspective of terminal operation. This is because when the base station turns off the corresponding SSB index, not only the TX chain but also the RX chain in the corresponding beam direction may be deactivated, which may result in a situation where the corresponding PRACH fails to be received at the base station.

[0264] According to one embodiment, if the terminal receives information indicating that a specific SSB index is turned off after PRACH corresponding to the specific SSB index is transmitted, the terminal may control the MSGB window as in the following options:

[0265] Option A: The terminal may terminate the MSGB window upon receiving information indicating that the corresponding SSB index is closed, and attempt to retransmit the MSGA including the PRACH. That is, the terminal may recognize that the MSGB corresponding to the transmitted MSGA will not be received, and may quickly terminate the MSGB window, thereby minimizing the delay of the random access process.

[0266] Option B: The terminal may maintain the MSGB window by considering that the on / off of the SSB is dynamically changed. That is, the terminal may maintain the MSGB window until receiving information indicating that the corresponding SSB is turned on.

[0267] Option C: The terminal can increase the MSGB window by X times by taking into account the dynamic changes of SSB on / off.

[0268] Depending on the frequency of turning on / off SSB, which of the above options is more efficient for the random access procedure may vary. Therefore, which of the above options can be set by the base station.

[0269] There may be a situation where the SSB changes from an off state to an on state during the random access process. For example, after the terminal sends the PRACH corresponding to SSB index 1, the terminal may receive information indicating that SSB index 2 is turned on when sending msg3 PUSCH. For example, the on information of SSB index 2 may be received in the same manner as described in [Implementation #1] above. In this case, the terminal may try to send msg3 PUSCH using the PO corresponding to SSB index 2. That is, the terminal may send msg3PUSCH using resources corresponding to SSB index 2 instead of resources associated with the previously sent PRACH. In order to increase the success probability of msg3 PUSCH, the base station may signal the SSB index value corresponding to msg3PUSCH through RAR.

[0270] Fig.17 An example of a RACH procedure based on SSB dynamically turned on / off in a wireless communication system according to an embodiment of the present disclosure is illustrated.

[0271] Reference Fig.17 In step S1701, the base station 1720 configures information about the actually transmitted SSB index through SIB1 or cell-common RRC signaling. The cell-common RRC signaling may include ServingCellCongCommon. For example, the base station 1720 may use ssb-PositionsInBurst in SIB1 or ServingCellCongCommon to configure information about the actually transmitted SSB index.

[0272] In step S1703, the base station 1720 uses a group common DCI or a group common MAC CE to dynamically signal the on / off information of the SSB index. For example, the base station 1720 may use a group common DCI or a group common MAC CE to signal the on / off information of the updated SSB index, as proposed in [Implementation #1].

[0273] In step S1705, UE 1710 performs SSB to RO mapping based on the signaling of base station 1720. For example, UE 1710 may perform SSB to RO mapping based on SIB1 or cell-common RRC signaling, and then re-perform SSB to RO mapping based on on / off information of each SSB index updated through group-common DCI or group-common MACCE.

[0274] In step S1707, the UE 1710 performs PRACH transmission based on the SSB-to-RO mapping. For example, the UE 1710 determines RACH resources based on the SSB-to-RO mapping, and transmits a RACH preamble using the determined RACH resources.

[0275] [Implementation #3] RLM (Radio Link Monitoring) / CBD (Candidate Beam Detection) / BFD (Beam Failure Detection) / Mobility Management

[0276] When performing RLM and / or link recovery procedures, the terminal can receive a configuration for a specific RS and determine whether a radio link failure (RLF) or beam failure detection (BFD) occurs based on the RS. For example, the specific RS may include an SSB index, a CSI-RS resource configuration index, or a TCI state index.

[0277] If the configuration of the corresponding RS is not received, the terminal may determine the RS according to a predefined rule. For example, the predefined rule may include a rule for the association between the TCI state set in the CORESET and the RS.

[0278] If SSB index #n is updated to the closed state while the terminal performs RLM, CBD, BFD and / or mobility management based on SSB index #n, a problem may occur when performing RLM, CBD, BFD and / or mobility management operations of the terminal. Here, the terminal can recognize that SSB index #n is updated to the closed state by the method proposed in [Implementation #1] above. Therefore, the operation of the terminal is as follows.

[0279] Fig.18 An example of a process for performing a designated operation based on SSB on / off information in a wireless communication system according to an embodiment of the present disclosure is illustrated. Fig.18 The operation method of the terminal is illustrated.

[0280] Reference Fig.18 In step S1801, the terminal selects the first RS based on the SSB index 1 in the on state. For example, the terminal may receive an SSB with an index 1 among the SSB indexes in the on state, and select the first RS corresponding to the SSB index 1 based on a predefined rule. Here, the predefined rule may define an association between the SSB index and the RS.

[0281] In step S1803, the terminal performs link-related operations based on the first RS. For example, the link-related operations may include at least one of RLM, CBD, BFD, or mobility management.

[0282] In step S1805, the terminal recognizes that SSB index 1 is changed to a closed state. For example, the terminal may receive closing information of SSB index 1 while performing a designated operation.

[0283] In step S1807, the terminal performs link-related operations based on the second RS. For example, the link-related operations may include at least one of RLM, CBD, BFD, or mobility management. That is, when it is identified that the SSB index 1 corresponding to the first RS is closed, the terminal replaces the first RS with the second RS. At this time, the second RS for replacing the first RS can be pre-set or pre-defined.

[0284] Specifically, the following alternatives may be used.

[0285] According to alternative scheme 3-1, the base station can pre-configure multiple RS sets, and the terminal can determine which RS set performs RLM, CBD, BFD and / or mobility management based on the on / off information of the SSB. Here, the on / off information of the SSB may include or be replaced by the validity of the CSI-RS resources or the on / off information of the TRP. At this time, the validity of the CSI-RS resources can be directly signaled for each CSI-RS resource, or the validity of the CSI-RS resources can be determined by on / off signaling for all or some associated antenna ports. In addition, when the terminal receives signals from multiple TRPs, the on / off of each TRP can be signaled.

[0286] For example, for RLM, CBD, BFD and / or mobility management operations, the terminal can receive configuration information of RS set #1 and RS set #2 in advance, and when SSB #n is in the on state, perform RLM, CBD, BFD and / or mobility management operations based on RS set #1, and when SSB #n is in the off state, perform RLM, CBD, BFD and / or mobility management operations based on RS set #2.

[0287] According to alternative scheme 3-1, when performing RLM or BFD, the RLM or BFD operation can be performed based on the frequency of occurrence of an event corresponding to RLF or beam failure during a certain timer period. For example, when performing an RLM or BFD operation based on the current SSB index #n, if information indicating that the corresponding SSB index #n is turned off is received, the terminal can maintain the corresponding timer value, and when the corresponding SSB index #n is turned on again, the terminal can resume the corresponding timer.

[0288] Depending on the frequency of turning SSB on / off, which of the above alternatives is more efficient may vary. Therefore, which of the above alternatives is selected may be set by the base station.

[0289] [Implementation #4] Handover Process

[0290] If a specific SSB index or CSI-RS resource of the target cell is superior in handover, or a specific SSB index or CSI-RS resource of the serving cell is superior in contention-free random access (CFRA), a RACH corresponding to the corresponding downlink RS may be set. If a preamble for handover or CFRA purposes is instructed to be sent in a RACH corresponding to SSB index #n, and information indicating that the corresponding SSB index #n is turned off is received, there may be a question of how to handle the instruction for RACH transmission. In this case, the terminal may perform one of the following options.

[0291] Option 1: The terminal may abandon RACH transmission.

[0292] Option 2: The terminal may retry RACH transmission after switching to CBRA (contention-based random access).

[0293] Option 3: Even if no RAR is received after RACH transmission, the terminal may not increase the power ramp counter and / or the RACH retransmission counter.

[0294] [Implementation #5] Method for determining PDCCH monitoring timing (MO) corresponding to SIB1 / paging / PEI (paging early indication)

[0295] As shown in [Table 13] and [Table 14] below, PDCCH MO (Monitoring Occasion) may be determined based on ssb-PositionsInBurst information set via SIB1. This is particularly true when SearchSpaceId is not 0. [Table 13] below illustrates a portion of TS38.304.

[0296] [Table 13]

[0297]

[0298]

[0299] The following [Table 14] illustrates a part of TS38.304.

[0300] [Table 14]

[0301]

[0302] As described in [Implementation #1], when the on / off information of a specific SSB index is updated through DCI, PDSCH or MAC CE, SSB to MO mapping can be performed by considering the updated on / off information. In this case, the operation of the terminal is as follows.

[0303] Fig.19 An example of a process for controlling a PDCCH MO based on SSB on / off information in a wireless communication system according to an embodiment of the present disclosure is illustrated. Fig.19 The operation method of the terminal is illustrated.

[0304] Reference Fig.19 In step S1901, the terminal identifies the on / off mode of the SSB. The on / off mode of the SSB can be identified according to the above various embodiments. Specifically, the terminal can identify the on / off mode of the SSB based on the signaling from the base station.

[0305] In step S1903, the terminal determines the mapping between the SSB and the MO. Each of the SSBs sent from the base station is associated with at least one MO, and the terminal performs SIB reception, paging, or PDCCH monitoring for PEI in the MO associated with the detected SSB. According to various embodiments, since the index of the transmitted SSB can be changed by controlling the on / off mode of the SSB, the terminal can reconfigure the mapping relationship between at least one SSB in the on state and the MO based on the on / off mode of the SSB. In order to reconfigure the mapping relationship between the SSB and the MO, according to one embodiment, the terminal may newly define the mapping with all MOs according to at least one SSB in the on state. According to another embodiment, the terminal may regard at least one MO associated with at least one SSB in the off state as invalid or associated with another SSB in the on state.

[0306] In step S1905, the terminal performs PDCCH monitoring. Specifically, the terminal can detect the SSB and perform PDCCH monitoring in the MO associated with the detected SSB.

[0307] Specifically, the SSB to MO mapping may follow at least one of the following alternatives.

[0308] According to alternative scheme 5-1, the terminal can re-perform SSB to MO mapping using only the SSB index in the on state based on the SSB index whose on / off information is updated. That is, the X value of [Table 13] and / or the N value of [Table 14] can be updated by the on / off information described in [Implementation #1]. For example, if the number of SSB indexes actually transmitted determined based on the ssb-PositionsInBurst information configured via SIB1 is 4, and as described in [Implementation #1], one of the SSB indexes that are turned off is signaled via DCI or PDSCH, the X value of [Table 12] and / or the N value of [Table 13] can be 3.

[0309] According to alternative scheme 5-2, the terminal may maintain the SSB to MO mapping based on the ssb-PositionsInBurst information configured via the existing SIB1, and may regard the MO corresponding to the SSB index in the closed state as invalid based on the updated on / off information. Alternatively, the terminal may not regard the MO corresponding to the SSB index in the closed state as invalid, but may regard them as corresponding to the SSB index mapped near the MO. For example, assume the case where MO#1 is associated with SSB index 1 and MO#2 is associated with SSB index 2. In this case, if SSB index 2 is changed to the closed state through DCI, the terminal may regard MO#2 as invalid, or regard MO#2 as associated with SSB index 1.

[0310] When applying the above alternative scheme, the number of MOs can also be changed based on the number of SSB indexes in the on state. For example, if the number of MOs is reduced as much as the number of SSB indexes in the on state, the energy saving effect of the base station can be maximized. Specifically, the K SSB indexes in SIB1 are actually sent, and the number of PDCCH monitoring opportunities in the SI window or nrofPDCCH-MonitoringOccasionPerSSB-InPO can be set to N through cell common RRC signaling such as system information. If K / 2 of the K SSB indexes are turned off via DCI, the number of PDCCH monitoring opportunities in the SI window or nrofPDCCH-MonitoringOccasionPerSSB-InPO can also be reduced to N / 2. At this time, N / 2 MOs out of N MOs can be determined according to a predetermined rule or preconfiguration of the base station. For example, the predefined rules may include a rule that the first N / 2 time slots in the N time slots in the frame are considered valid, or a rule that one MO in two consecutive MOs is considered valid and the next MO is considered invalid.

[0311] [Embodiment #6] Method for performing SSB and / or CSI-RS related procedures (e.g., procedures for mobility) through SMTC (SSB measurement timing configuration)

[0312] For RRM measurement, the terminal can receive SMTC from the base station. SMTC includes timing information about periodicity and / or offset, and the terminal can perform measurements on the SSB and / or CSI-RS of at least one cell during the set time. At this time, the index of the SSB or CSI-RS resource information for performing measurements on the SSB and / or CSI-RS of at least one cell can be configured together.

[0313] Fig. 20An example of a process for measuring SSB based on SMTC in a wireless communication system according to an embodiment of the present disclosure is illustrated. Fig. 20 The signaling between the base station and the terminal and the operation according to the signaling are illustrated.

[0314] Reference Fig. 20 In step S2001, the terminal receives a plurality of SMTCs from the base station. Each of the plurality of SMTCs may include timing information of a period and / or offset to be used for measuring an SSB and / or CSI-RS of at least one cell.

[0315] In step S2003, the terminal selects an SMTC from a plurality of SMTCs. The terminal selects an SMTC from a plurality of SMTCs based on at least one of the NES state, the DRX configuration, or the active time of the base station. For example, in the NES state, the terminal may select a first SMTC from a plurality of SMTCs, and in the non-NES state, the terminal may select a second SMTC from a plurality of SMTCs. As another example, when cell DTX / DRX is configured, the terminal may select a first SMTC from a plurality of SMTCs, and when UE-specific DRX is configured, the terminal may select a second SMTC from a plurality of SMTCs. As another example, when this is the active time of the base station, the terminal may select a first SMTC from a plurality of SMTCs, and when this is not the active time of the base station, the terminal may select a second SMTC from a plurality of SMTCs.

[0316] In step S2005, the terminal performs measurement on the SSB or CSI-RS according to the selected SMTC. For example, the terminal may measure the SSB or CSI-RS based on timing information about the period and / or offset of the selected SMTC.

[0317] According to one embodiment, the terminal may receive two or more SMTCs, and after identifying whether it is in the NES state according to the above embodiment, or after determining which NES state it is, perform the SMTC operation. For example, if SMTC_A and SMTC_B are set, a rule may be defined to apply SMTC_A when SMTC_A is in the NES state, and to apply SMTC_B when SMTC_B is not in the NES state. In this case, by setting SMTC_A to have a longer period than SMTC_B, the power of the base station can be saved.

[0318] According to another embodiment, the base station may set multiple candidate values ​​for timing information (such as the periodicity of an SMTC), or set multiple sets for the SSB index or CSI-RS resource information to be measured. In addition, the terminal may use the corresponding parameter set to perform measurements depending on whether it is in an NES state or which NES state it is. For example, for an SMTC, if {0, 1} is set as SSB index set A and {0, 1, 2, 3} is set as SSB index set B, the terminal may apply SSB index set A and perform measurements based thereon when in an NES state, or apply SSB index set B and perform measurements based thereon when not in an NES state. Conversely, the terminal may apply SSB index set B and perform measurements based thereon when in an NES state, or apply SSB index set A and perform measurements based thereon when not in an NES state.

[0319] As another example, for one SMTC, if multiple CSI-RS sets (e.g., CSI-RS set #1 / #2 / #3 / #4) are configured, the terminal may apply CSI-RS set #1 when not in the NES state, apply CSI-RS set #2 when in the NES state #0, apply CSI-RS set #3 when in the NES state #1, and apply CSI-RS set #4 when in the NES state #2, and perform measurement. Here, the correspondence between the NES state and the CSI-RS set may be predefined or configured.

[0320] Alternatively, the terminal can receive multiple SMTCs, and one of the different SMTC operations is performed depending on the activated DRX configuration or whether it is the active time of the base station. In the present disclosure, the DRX configuration can be a DRX configuration configured for an idle / inactive terminal, a C-DRX configuration configured for a connected terminal, or a configuration (hereinafter referred to as cell DTX / DRX) including a DTX and / or DRX mode of a base station in a cell-specific or UE group-common manner. In addition, the active time of the base station can represent the on-duration in the DRX configuration, the period during which the inactive timer is running, and / or the period during which the DL / UL signal transmission and reception of the base station can be expected. For example, if SMTC_A and SMTC_B are configured, a rule can be defined to apply SMTC_A when it is not the active time of the base station, and to apply SMTC_B when it is the active time of the base station. In this case, by setting SMTC_A to have a longer period than SMTC_B, the power of the base station can be saved. For another example, a rule may be defined to apply SMTC_A when cell DTX / DRX is configured / indicated, and to apply SMTC_B when UE-specific DRX is configured / indicated.

[0321] According to another embodiment, the base station may set multiple candidate values ​​for the timing information, such as the period of one SMTC, or set multiple sets for the SSB index or CSI-RS resource information to be measured. In addition, the terminal may apply one of the different parameter sets according to the activated DRX configuration or whether it is the active time of the base station, and perform measurements. For example, for one SMTC, if SSB index set A is set to {0, 1} and SSB index set B is set to {0, 1, 2, 3}, the terminal may apply SSB index set A when it is not the active time of the base station, and apply SSB index set B when it is the active time of the base station, and perform measurements. On the contrary, if it is not the active time of the base station, the terminal may apply SSB index set B, and if it is the active time of the base station, apply SSB index set A, and perform measurements. For another example, the terminal may apply SSB index set A when configuring / indicating cell DTX / DRX, apply SSB index set B when configuring / indicating UE-specific DRX configuration, and perform measurements. In contrast, the terminal may apply SSB index set B when configuring / indicating cell DTX / DRX and apply SSB index set A when configuring / indicating UE-specific DRX configuration, and perform measurement.

[0322] At the same time, when DRX is configured, the terminal may assume that the base station does not send downlink signals such as SSB during periods that are not active time of the base station. This is to minimize the power consumption of the base station during periods that are not active time. However, since it is difficult for the terminal to obtain time / frequency synchronization and / or perform RRM measurements through SSB during this period, a stable network connection may not be easy. In view of this, the terminal may expect to receive downlink signals (including SSB) for measurement purposes during the period set as SMTC, even if the period is not the active time of the base station.

[0323] Alternatively, depending on which DRX is configured and / or indicated, the terminal assumption for the SMTC during the period that is not the active time of the base station may be different. That is, if DRX configuration #1 is configured / indicated, downlink signal reception including SSB for measurement purposes may be expected in the SMTC during the period that is not the active time of the base station, while if DRX configuration #2 is configured / indicated, downlink signal reception is not expected in the SMTC even during the period that is not the active time of the base station. In this case, DRX configuration #2 may be the cell DTX / DRX configuration.

[0324] [Implementation #7] Method for setting multiple SSB-related parameters and interpreting the SSB-related parameters received from the corresponding service cell differently according to the terminal's capabilities

[0325] The SSB-related parameters may include at least one of the SSB period or the transmitted SSB index. In the NR system, the period value of the SSB can be cell-specifically set by the ssb-periodicityServingCell parameter. For example, if the period value of the SSB is set to 20 milliseconds, as described in [Implementation #1] above, if the on / off or power value is changed by the SSB index or the SSB index group, even if the existing terminal that does not have the ability to identify the configuration change accesses the cell, it is difficult to expect stable reception of the SSB. Taking into account the operation of such existing terminals, when the period value of the SSB is set to 160 milliseconds, the on / off or power value can be set differently for the SSB sent outside the corresponding period. However, there is the following disadvantage: even to a terminal that has the ability to identify such a change, the actual period information of the SSB cannot be provided.

[0326] In the following, for ease of description, a terminal having the ability to identify that a transmission mode (such as turning on / off an SSB index or index group) changes periodically or that a power value changes according to an SSB index or index group is referred to as a "terminal with NES capability". In order to solve this problem, considering a terminal with NES capability and a terminal without such capability (hereinafter referred to as a "non-NES capable terminal"), according to one embodiment, a separate different parameter may be used to set the SSB period. That is, in addition to the period value of the SSB set via the ssb-periodicityServingCell parameter (hereinafter referred to as "period #1"), a separate RRC parameter may be used to set the period value of the SSB (hereinafter referred to as "period #2"). The existing SSB period value (period #1) may be set for a terminal without NES capability, and in addition to the period #1 for a terminal with NES capability, a period #2 value may also be set. Here, period #2 may be a value smaller than period #1. For a terminal with NES capability, the SSB is sent according to cycle #2, and on / off and / or power control may be applied according to the SSB index or index group by the same method as in [Implementation #1] above. In addition, a terminal with NES capability may assume and / or expect that the SSB index is sent semi-statically as the SSB previously sent according to cycle #1.

[0327] As discussed in TS 38.331 above, whether to send an SSB index can be semi-statically signaled via a bitmap per SSB index or per group of indexes (e.g., ssb-PositionsInBurst in SIB1 or ServingCellConfigCommon). As a motivation similar to the SSB period, the corresponding bitmap information can be set as separate different parameters for NES-capable terminals and non-NES-capable terminals. That is, in addition to the information about the transmission of each SSB index or SSB index group previously set via the ssb-PositionsInBurst parameter (hereinafter referred to as "bitmap #1"), the information about the transmission of each SSB index or index group can be set via a separate RRC parameter (hereinafter referred to as "bitmap #2"). For terminals without NES capability, bitmap #1 can be set, and for terminals with NES capability, bitmap #2 can be set in addition to the existing bitmap #1. Here, bitmap #2 can carry more information than bitmap #1. For a terminal with NES capability, SSB may be sent based on bitmap #2, and according to the method in [Implementation #1] above, for at least some SSB indexes or group indexes based on bitmap #2, on / off may vary according to the SSB index or index group. In addition, a terminal with NES capability may assume and / or expect that the SSB index is sent semi-statically as previously for the SSB index based on bitmap #1.

[0328] Fig.21 An example of a process for setting SSB-related parameters according to terminal capabilities in a wireless communication system according to an embodiment of the present disclosure is illustrated. Fig.21 The signaling between the base station and the terminal and the operation according to the signaling are illustrated.

[0329] Reference Fig.21 In step S2101, the base station 2120 configures SSB related parameters according to the terminal capability. That is, the base station 2120 sets the SSB related parameters for the terminal without NES capability and the SSB related parameters for the terminal with NES capability. The SSB related parameters include at least one of the SSB period or the transmitted SSB index.

[0330] In step S2103, the base station 2120 sends SSB related parameters to the terminal 2110. The base station 2120 may send the SSB related parameters to the terminal 2110 using an existing ssb-periodicityServingCell parameter or a separate RRC parameter according to the terminal capability.

[0331] In step S2105, the terminal 2110 selects and applies SSB related parameters according to its capabilities. For example, in the case of a terminal without NES capabilities, the terminal 2110 can select and apply SSB related parameters for a terminal without NES capabilities, and the terminal 2110 can select and apply SSB related parameters for a terminal with NES capabilities.

[0332] [Implementation #8] Method for controlling cell selection or random access operation by giving different thresholds and / or offset values ​​between terminals with NES capability and terminals without NES capability

[0333] In events A1 / A2 / A3 / A4 / A5 / A6, etc. defined in Section 5.5.4 of TS 38.331, if an offset is given to the measurement result of the serving cell and / or the neighboring cell or the condition is satisfied by comparison with a threshold, a mobility-related operation such as handover or cell (re)selection can be performed. In this case, different offset values ​​or thresholds can be set for terminals with NES capability and terminals without NES capability.

[0334] For example, if the measurement result of the serving cell is equal to or less than a certain threshold, a handover event may be triggered. At this time, the threshold #1 value may be applied to a terminal with NES capability, and the threshold #2 value may be applied to a terminal without NES capability. If the on / off and / or power value of the SSB may change, the base station may set threshold #1>threshold #2, thereby reducing the probability of a handover event being triggered for a terminal without NES capability, even if the base station does not send some SSBs for NES purposes or sends some SSBs at low power.

[0335] In addition, during the random access process, operations such as selecting one of the best SSB or CSI-RS, selecting one of the two-step or four-step processes, or selecting one of NUL or SUL can be performed based on thresholds (e.g., rsrp-thresholdSSB, rsrp-thresholdCSI-RS, msgA-RSRP-thresholdSSB, rsrp-thresholdSSB-SUL, msgA-RSRP-threshold, rsrp-thresholdMsg3). For terminals with NES capabilities and terminals without NES capabilities, all or some thresholds can be set to different values. For example, if the RSRP measurement result of a specific SSB index is equal to or greater than a specific threshold, the PRACH preamble in the RO (RACH opportunity) corresponding to the SSB index can be sent. At this time, the threshold #1 value can be applied to terminals with NES capabilities, and the threshold #2 value can be applied to terminals without NES capabilities. If the on / off and / or power value of the SSB may change, the base station can increase the transmission probability of the RO and PRACH preamble codes corresponding to the SSB index of the terminal without NES capability by setting Threshold #1>Threshold #2, even if the base station does not send some SSBs for NES purposes or sends them at low power.

[0336] Fig. 22 An example of a process for controlling a threshold related to mobility according to terminal capabilities in a wireless communication system according to an embodiment of the present disclosure is illustrated. Fig. 22 The operation method of the terminal is illustrated.

[0337] Reference Fig. 22 , in step S2201, the terminal selects a threshold value based on the capability of the terminal. The threshold value may be a threshold value of a measurement result of a serving cell and / or a neighboring cell during a mobility operation such as handover or cell reselection. For example, in the case of a terminal with NES capability, the terminal may select a first threshold value corresponding to a terminal with NES capability, and in the case of a terminal without NES capability, the terminal may select a second threshold value corresponding to a terminal without NES capability. In this case, the second threshold value corresponding to a terminal without NES capability may be set to have a smaller value than the first threshold value corresponding to a terminal with NES capability.

[0338] In step S2203, the terminal identifies that the measurement result of the serving cell is lower than the selected threshold. For example, the terminal may determine whether the measurement result of the serving cell is lower than the selected threshold by comparing the measurement result of the serving cell with the selected threshold.

[0339] In step S2205, the terminal triggers a handover event. That is, if the measurement result of the serving cell is lower than the selected threshold, the terminal may trigger a handover event. Fig. 22 Not shown in the figure, but if the measurement result is not lower than the selected threshold, the terminal can terminate the process or perform the measurement again.

[0340] In reference Fig. 22 In the description, by allowing terminals without NES capability to use lower thresholds than terminals with NES capability, the probability of triggering a handover event in terminals without NES capability can be reduced when the base station does not send some SSBs for NES or sends some SSBs at low power.

[0341] As described above, the present disclosure enables a base station to dynamically turn on / off SSB for energy saving purposes. The present disclosure proposes a signaling method for dynamically turning on / off SSB, and proposes an operation method of a terminal for random access, measurement and / or broadcast data reception.

[0342] The example of the above-mentioned proposed method may be included as one of the implementation methods of the present disclosure, and thus may be regarded as a type of the proposed method. In addition, the above-mentioned proposed method may be implemented independently, or some of the proposed methods may be combined (or merged). The rule may be defined so that the base station notifies the UE of information on whether to apply the proposed method (or information about the rule of the proposed method) through a predefined signal (e.g., a physical layer signal or a higher layer signal).

[0343] Those skilled in the art will appreciate that the present disclosure can be implemented in other specific ways than those described herein without departing from the spirit and essential characteristics of the present disclosure. Therefore, the above exemplary embodiments should be interpreted in all respects as illustrative and not restrictive. The scope of the present disclosure should be determined by the appended claims and their legal equivalents, rather than by the above description, and it is intended that all changes that come within the meaning and equivalent range of the appended claims are covered therein. In addition, it will be apparent that some claims that refer to specific claims can be combined with another claim that refers to other claims other than the specific claims to constitute an embodiment, or new claims can be added by amendment after the application is submitted.

[0344] Industrial Applicability

[0345] Embodiments of the present disclosure are applicable to various radio access systems. Examples of various radio access systems include the 3rd Generation Partnership Project (3GPP) or 3GPP2 system.

[0346] The embodiments of the present disclosure are applicable not only to various radio access systems but also to all technical fields to which various radio access systems are applied. In addition, the proposed method is applicable to millimeter wave and terahertz wave communication systems using ultra-high frequency bands.

[0347] Additionally, embodiments of the present disclosure are applicable to a variety of applications, such as autonomous vehicles, drones, and the like.

Claims

1. A method for operating a terminal in a wireless communication system, the method comprising: Receiving downlink control information DCI related to system information; obtaining allocation information for receiving the system information based on the DCI; receiving the system information based on the allocation information; Obtaining first information related to a position of a synchronization signal / physical broadcast channel block SSB included in the system information; receiving second information related to turning on or off the SSB; as well as At least one of the SSBs is received based on the first information and the second information.

2. The method according to claim 1, wherein: The second information indicates turning on or off at least one SSB index corresponding to each bit using values ​​of bits included in the bitmap.

3. The method according to claim 2, wherein: The mapping between the bits included in the bitmap and the SSB index is determined based on the number of the SSBs and the number of bits indicated by the system information.

4. The method according to claim 1, wherein: The second information indicates shut down using a power value of a predefined value.

5. The method according to claim 1, further comprising: identifying at least one SSB index to be turned off based on the second information, The at least one SSB index that is closed includes multiple SSB candidate indexes, and the multiple SSB candidate indexes are associated with the SSB index indicated by the second information to be closed.

6. The method according to claim 1, wherein: The turning on or off of the SSB indicated by the second information is applied starting from a time point predefined or set by signaling.

7. The method according to claim 1, wherein: The turning on or off of the SSB based on the second information is applied based on the network energy saving NES state indicated from the base station.

8. The method according to claim 1, further comprising: identifying an on / off mode of the SSB based on the second information; reconfiguring the mapping between the SSB and random access channel opportunities RO based on the on / off mode of the SSB; as well as A random access channel (RACH) preamble is transmitted in the RO selected based on the mapping between the SSB and the RO.

9. The method according to claim 8, wherein: The mapping between the SSB and the RO is reconfigured by considering at least one RO associated with at least one SSB index that is turned off as invalid, considering at least one RO associated with at least one SSB index that is turned off as associated with an SSB index associated with an adjacent RO that is in an turned-on state, or sequentially mapping the remaining SSB indexes excluding at least one SSB index that is turned off to the RO.

10. The method according to claim 1, further comprising: Based on receiving the SSB of the first index, performing a link-related operation using the first reference signal RS; as well as The SSB based on the first index is turned off, performing the operation related to the link using a second RS instead of the first RS, The operation related to the link includes one of radio link monitoring RLM, candidate beam detection CBD, beam failure detection BFD or mobility management operation.

11. The method according to claim 1, further comprising: Based on receiving the SSB of the first index, performing a link-related operation using the first reference signal RS; as well as The SSB based on the first index is turned off, maintaining a timer associated with the operation associated with the link using the first RS, The operation related to the link includes one of radio link monitoring RLM, candidate beam detection CBD, beam failure detection BFD or mobility management operation.

12. The method according to claim 1, further comprising: identifying an on / off mode of the SSB based on the second information; reconfigure the mapping between the SSB and the physical downlink control channel PDCCH monitoring opportunity MO based on the on / off mode of the SSB; as well as The PDCCH is received in the PDCCH MO selected based on the mapping between the SSB and the PDCCH MO.

13. A method of operating a base station in a wireless communication system, the method comprising: Sending downlink control information DCI related to system information; transmitting system information including first information related to a location of a synchronization signal / physical broadcast channel block (SSB) based on the allocation information included in the DCI; Sending second information related to turning on or off the SSB; as well as At least one of the SSBs is sent based on the first information and the second information.

14. A terminal in a wireless communication system, the terminal comprising: Transceiver; as well as a processor connected to the transceiver, Wherein, the processor is configured to: Receiving downlink control information DCI related to system information; obtaining allocation information for receiving the system information based on the DCI; receiving the system information based on the allocation information; Obtaining first information related to a position of a synchronization signal / physical broadcast channel block SSB included in the system information; receiving second information related to turning on or off the SSB; and At least one of the SSBs is received based on the first information and the second information.

15. A base station in a wireless communication system, the base station comprising: Transceiver; as well as a processor connected to the transceiver, Wherein, the processor is configured to: Sending downlink control information DCI related to system information; transmitting system information including first information related to a location of a synchronization signal / physical broadcast channel block (SSB) based on the allocation information included in the DCI; sending second information related to turning on or off the SSB; and At least one of the SSBs is sent based on the first information and the second information.

16. A communication device, comprising: at least one processor; as well as at least one computer memory connected to the at least one processor and configured to store instructions directing operations performed by the at least one processor, The operations include: Receiving downlink control information DCI related to system information; obtaining allocation information for receiving the system information based on the DCI; receiving the system information based on the allocation information; Obtaining first information related to a position of a synchronization signal / physical broadcast channel block SSB included in the system information; receiving second information related to turning on or off the SSB; and At least one of the SSBs is received based on the first information and the second information.

17. A non-transitory computer-readable medium storing at least one instruction, the non-transitory computer-readable medium including the at least one instruction executable by a processor, in, The at least one instruction controls the device to: Receiving downlink control information DCI related to system information; obtaining allocation information for receiving the system information based on the DCI; receiving the system information based on the allocation information; Obtaining first information related to a position of a synchronization signal / physical broadcast channel block SSB included in the system information; receiving second information related to turning on or off the SSB; as well as At least one of the SSBs is received based on the first information and the second information.

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