Apparatus and method for transmitting and receiving cell discovery signal in wireless communication system

Abstract

The present disclosure is to transmit and receive a cell discovery signal in a wireless communication system, a method of operating a terminal may include: receiving at least one synchronization signal and a broadcast channel block (SSB); obtaining synchronization for the base station using a synchronization signal included in the SSB; obtaining system information using a master information block (MIB) included in the SSB; performing a random access procedure based on the system information; and performing tracking on at least one of time or frequency using a reference signal multiplexed with the at least one SSB on a time axis or a frequency axis.

Description

Technical Field

[0001] The following description relates to a wireless communication system, and to an apparatus and method for transmitting and receiving a cell discovery 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 efficiently operating a cell discovery signal in a wireless communication system.

[0006] The present disclosure may provide an apparatus and method for reducing energy consumption due to transmission of a Tracking Reference Signal (TRS) in a wireless communication system.

[0007] The present disclosure may provide an apparatus and method for multiplexing an SSB (Synchronization Signal and Broadcast Channel Block) and a TRS in a wireless communication system.

[0008] The present disclosure may provide an apparatus and method for transmitting and receiving a burst including an SSB and a TRS in a wireless communication system.

[0009] The present disclosure may provide an apparatus and method for improving the accuracy of frequency axis synchronization acquisition of a TRS multiplexed with an SSB in a wireless communication system.

[0010] The present disclosure may provide an apparatus and method for mapping a TRS to resources by considering the structure of an SSB in a wireless communication system.

[0011] The present disclosure may provide an apparatus and method for indicating an SSB multiplexed with a TRS in a wireless communication system.

[0012] The present disclosure may provide an apparatus and method for indicating a multiplexing structure of SSB and TRS in a wireless communication system.

[0013] The present disclosure may provide an apparatus and method for supporting transmission of a cell discovery signal including an SSB and a TRS for each cell in a wireless communication system.

[0014] The present disclosure may provide an apparatus and method for signaling information about the power of a TRS multiplexed with an SSB in a wireless communication system.

[0015] 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.

[0016] Technical Solution

[0017] As an example of the present disclosure, a method for operating a terminal may include: receiving at least one synchronization signal and a broadcast channel block (SSB); obtaining synchronization of a base station using a synchronization signal included in the SSB; obtaining system information using a master information block (MIB) included in the SSB; performing a random access procedure based on the system information; and performing tracking of at least one of time or frequency using a reference signal multiplexed with the at least one SSB on a time axis or a frequency axis.

[0018] As an example of the present disclosure, a method for operating a base station in a wireless communication system may include: sending at least one synchronization signal and a broadcast channel block (SSB); sending a reference signal multiplexed with the at least one SSB on a time axis or a frequency axis; sending system information related to a random access channel; and performing a random access process based on the system information.

[0019] 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 at least one synchronization signal and a broadcast channel block (SSB), obtain synchronization of a base station using a synchronization signal included in the SSB, obtain system information using a master information block (MIB) included in the SSB, perform a random access procedure based on the system information, and perform tracking on at least one of time or frequency using a reference signal multiplexed with at least one SSB on a time axis or a frequency axis.

[0020] 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 at least one synchronization signal and a broadcast channel block (SSB), send a reference signal multiplexed with at least one SSB on a time axis or a frequency axis, send system information related to a random access channel, and perform a random access procedure based on the system information.

[0021] 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 for guiding operations performed by the at least one processor. These operations may include: receiving at least one synchronization signal and a broadcast channel block (SSB); obtaining synchronization of a base station using a synchronization signal included in the SSB; obtaining system information using a master information block (MIB) included in the SSB; performing a random access procedure based on the system information; and tracking at least one of time or frequency using a reference signal multiplexed with the at least one SSB on a time axis or a frequency axis.

[0022] As an example of the present disclosure, a non-transitory computer-readable medium storing at least one instruction may include the at least one instruction that can be executed by a processor. The at least one instruction can control a device to receive at least one synchronization signal and a broadcast channel block (SSB); obtain synchronization of a base station using a synchronization signal included in the SSB; obtain system information using a master information block (MIB) included in the SSB; perform a random access procedure based on the system information; and perform tracking of at least one of time or frequency using a reference signal multiplexed with the at least one SSB on a time axis or a frequency axis.

[0023] 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.

[0024] Beneficial Effects

[0025] As is apparent from the above description, the embodiments of the present disclosure have the following effects.

[0026] According to the present disclosure, the energy consumption of a base station can be reduced.

[0027] 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

[0028] 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.

[0029] Figure 1 An example of a structure of a wireless communication system to which the present disclosure can be applied is illustrated.

[0030] Figure 2 An example of a wireless device applicable to the present disclosure is illustrated.

[0031] Figure 3 The frame structure in a wireless communication system to which the present disclosure can be applied is illustrated.

[0032] Figure 4 An example of a resource grid in a wireless communication system to which the present disclosure can be applied is illustrated.

[0033] Figure 5 An example of a physical resource block in a wireless communication system to which the present disclosure can be applied is illustrated.

[0034] Figure 6 An example of a time slot structure in a wireless communication system to which the present disclosure can be applied is illustrated.

[0035] 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.

[0036] Figure 8 The structure of an SSB (synchronization signal and broadcast channel block) applicable to the present disclosure is illustrated.

[0037] Fig. 9 The transmission of SSB applicable to the present disclosure is illustrated.

[0038] Fig.10 Examples of SSB candidate positions applicable to the present disclosure are illustrated.

[0039] Fig.11 An example of downlink time synchronization information applicable to the present disclosure is illustrated.

[0040] Fig.12 An example of the difference in distance between a terminal and a macro cell and a small cell in a carrier aggregation environment is illustrated.

[0041] Fig.13 An example of a process for receiving a cell discovery signal in a wireless communication system according to an embodiment of the present disclosure is illustrated.

[0042] Fig.14 An example of a process for transmitting a cell discovery signal in a wireless communication system according to an embodiment of the present disclosure is illustrated.

[0043] Fig.15 An example of multiplexing SSB and TRS (Tracking Reference Signal) in a wireless communication system according to an embodiment of the present disclosure is illustrated.

[0044] Fig.16 The SSB transmission timing for each case in the wireless communication system according to the embodiment of the present disclosure is illustrated.

[0045] Fig.17 An example of a process for signaling a structure of a cell discovery signal in a wireless communication system according to an embodiment of the present disclosure is illustrated. DETAILED DESCRIPTION

[0046] 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.

[0047] 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.

[0048] 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.

[0049] 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.

[0050] 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.

[0051] 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.

[0052] 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.

[0053] 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.

[0054] 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 disclosure are applicable to systems applied after the 3GPP 5G NR system and are not limited to a specific system.

[0055] 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.

[0056] 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.

[0057] 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.

[0058] 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.

[0059] 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.

[0060] 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.

[0061] 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.

[0062] Overall system

[0063] 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.

[0064] 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.

[0065] 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.

[0066] 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.

[0067] 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.

[0068] Figure 2 An example of a wireless device applicable to the present disclosure is illustrated.

[0069] refer to Figure 2 The 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.

[0070] 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.

[0071] 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.

[0072] 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.

[0073] 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.

[0074] 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.

[0075] refer to Figure 2 The 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.

[0076] 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.

[0077] 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.

[0078] 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.

[0079] 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.

[0080] 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.

[0081] 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 (eg, 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.

[0082] Figure 3 The frame structure in a wireless communication system to which the present disclosure can be applied is illustrated.

[0083] 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.

[0084] 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.

[0085] [Table 1]

[0086] μ <![CDATA[Δf=2 μ ·15[kHz]]]> CP 0 15 normal 1 30 normal 2 60 Normal, Extended 3 120 normal 4 240 normal

[0087] 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.

[0088] 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).

[0089] [Table 2]

[0090] Frequency range specification Corresponding frequency range Subcarrier spacing FR1 410MHz-7125MHz 15, 30, 60kHz FR2 24250MHz-52600MHz 60, 120, 240kHz

[0091] 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 is 480·103Hz, 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.

[0092] 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.

[0093] [Table 3]

[0094]

[0095] [Table 4]

[0096]

[0097] 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.

[0098] 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.

[0099] 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.

[0100] 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.

[0101] Figure 4 A resource grid in a wireless communication system to which the present disclosure can be applied is illustrated.

[0102] 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 μOFDM 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, is an index in the frequency domain, and 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, 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.

[0103] Point A plays the role of a common reference point for the resource block grid and is obtained as follows.

[0104] -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.

[0105] -absoluteFrequencyPointA represents the frequency location of point A, as expressed in absolute radio frequency channel number (ARFCN).

[0106] 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.

[0107] [Formula 1]

[0108]

[0109] 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.

[0110] [Formula 2]

[0111]

[0112] is the common resource block where the BWP starts relative to common resource block 0.

[0113] 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.

[0114] 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.

[0115] 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.

[0116] 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).

[0117] 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.

[0118] 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.

[0119] 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.

[0120] 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.

[0121] 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).

[0122] 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.

[0123] 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.

[0124] 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.

[0125] SSB (Synchronization Signal Block) transmission and related operations

[0126] 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.

[0127] 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.

[0128] Community Search

[0129] 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.

[0130] The cell search process of the terminal can be summarized as shown in the following [Table 5].

[0131] [Table 5]

[0132]

[0133] 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].

[0134] [Formula 3]

[0135] in, and

[0136] in, represents the cell ID (e.g., PCID), represents a cell ID group and is provided / obtained through SSS,

[0137] Indicates a cell ID within a cell ID group and is provided / obtained through the PSS.

[0138] PSS sequence d PSS (n) can be defined as satisfying [Equation 4].

[0139] [Formula 4]

[0140] d PSS (n) = 1-2x(m)

[0141]

[0142] Where 0≤n<127, x(i+7)=(x(i+4)+x(i))mod 2, and

[0143] [x(6)x(5)x(4)x(3)x(2)x(1)x(0)]=[11 1 0 1 10]

[0144] SSS sequence d SSS (n) can be defined as satisfying [Equation 5].

[0145] [Formula 5]

[0146] d SSS (n)=[1-2x0((n+m0)mod 127)][1-2x1((n+m1)mod 127)]

[0147]

[0148] Among them, 0≤n>127, x0(i+7)=(x0(i+4)+x0(i))mod2, x1(i+7)=(x1(i+1)+x1(i))mod2,

[0149] [x0(6)x0(5)x0(4)x0(3)x0(2)x0(1)x0(0)] = [0 0 0 0 0 0 1] and

[0150] [x1(6)x1(5)x1(4)x1(3)x1(2)x1(1)x1(0)]=[0 0 0 0 0 0 1].

[0151] 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.

[0152] - For the frequency range up to 3 GHz, L = 4

[0153] - For the frequency range of 3 GHz to 6 GHz, L = 8

[0154] - For the frequency range of 6 GHz to 52.6 GHz, L = 64

[0155] 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.

[0156] - Case A - 15kHz SCS: The index of the starting symbol of the candidate SSB is given as {2, 8} + 14*n.

[0157] - For operation without shared spectrum channel access (eg, L-band, LCell): If the carrier frequency is 3 GHz or less, n = 0, 1. If the carrier frequency is 3 GHz to 6 GHz, n = 0, 1, 2, 3.

[0158] - For operation with shared spectrum channel access (eg, U-band, UCell): n=0, 1, 2, 3, 4.

[0159] - 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.

[0160] - Case C - 30kHz SCS: The index of the starting symbol of the candidate SSB is given as {2, 8}+14*n.

[0161] - 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.

[0162] - For operation without shared spectrum channel access: n=0, 1, 2, 3, 4, 6, 7, 8, 9.

[0163] - 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.

[0164] - 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.

[0165] 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 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].

[0166] [Table 6]

[0167]

[0168] 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.10 The 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.10In 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 a PRB including SSB transmission resources in an OFDM symbol in which an SSB is transmitted is unavailable for a PDSCH (ie, not mapped).

[0169] 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.

[0170] 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).

[0171] 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.

[0172] 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).

[0173] CSI-RS (or TRS) for tracking

[0174] TRS is defined in NR for the functionality of CRS (cell-specific reference signal) for fine time and frequency tracking in LTE systems. However, unlike the CRS of LTE systems, the TRS defined in NR is not an always-on method. Thanks to the TRS defined in NR, the terminal can estimate timing offset, delay spread, frequency offset, and Doppler spread. TRS is supported in both below 6 GHz (FR1) and above 6 GHz (FR2).

[0175] Periodic TRS is mandatory in both FR1 and FR2, and aperiodic TRS is optional in both FR1 and FR2. The terminal receives an NZP-CSI-RS-ResourceSet information element (IE) including a trs-Info parameter from the base station. The trs-Info parameter is a parameter indicating whether the antenna ports of all NZP-CSI-RS resources in the CSI-RS resource set are the same, and the trs-Info parameter is set in units of NZP-CSI-RS resource sets.

[0176] The CSI-RS resources whose trs-Info parameter in the CSI-RS resource set is set to "ON" are set to 1-port CSI-RS resources. The periodic CSI-RS resources whose trs-Info parameter in the CSI-RS resource set is set to "ON" have the same period, bandwidth, and subcarrier position. In addition, the non-periodic CSI-RS resources whose trs-Info parameter in the CSI-RS resource set is set to "ON" have the same bandwidth, the same RB position, and the same number of CSI-RS resources. If a non-periodic TRS is set, the QCL reference of the TRS should be associated with the periodic TRS, and the QCL types are "QCL-Type-A" and "QCL-TypeD". Next, the terminal performs time and / or frequency tracking through the CSI-RS resources whose trs-Info in the CSI-RS resource set is set to "ON".

[0177] Specific embodiments of the present disclosure

[0178] Hereinafter, the present disclosure is to operate a cell discovery signal in a wireless communication system, and propose a structure of the cell discovery signal and a technology for transmitting and receiving the cell discovery signal of the proposed structure.

[0179] Fig.12 An example of the difference in distance between a terminal and a macro cell and a small cell in a carrier aggregation environment is illustrated. Fig.12 , in a carrier aggregation (CA) environment (e.g., a combination of 15kHz SCS Scell ​​in FR1+120kHz SCS Scell ​​in FR2) for a macro cell 1210 and a small cell 1220, when the difference between the distance between the terminal and the macro cell and the distance between the terminal and the small cell is about 175m or more, the propagation delay may be greater than the 20kHz SCS CP length (=about 586 nanoseconds). Here, the macro cell may include at least one of a primary cell (Pcell) or a primary secondary cell (PScell), and the small cell may include a secondary cell.

[0180] In this carrier aggregation situation, it may happen that the difference in signal reception timing between the primary cell and the secondary cell is greater than the CP length based on the SCS of the secondary cell. Therefore, it is necessary to send a signal on the secondary cell to compensate for this.

[0181] The existing NR system allows the terminal to receive SSB (SS (Synchronization Signal) / PBCH (Physical Broadcast Channel) Block) and / or TRS (Tracking Reference Signal) on the secondary cell to obtain fine time / frequency synchronization of the secondary cell in preparation for the above situation. Figure 1As shown, in the case of carrier aggregation of FR1 service cell and FR2 service cell, the terminal may include separate RF chains and frequency oscillators for FR1 and FR2. In this case, the terminal obtains coarse time / frequency axis synchronization by utilizing at least one of the primary synchronization signal (PSS), the secondary synchronization signal (SSS) or the PBCH DM-RS, and additionally obtains fine time / frequency axis synchronization by TRS, thereby minimizing the degree of time / frequency synchronization misalignment between the primary cell or the primary and secondary cells and the secondary cells.

[0182] However, when SSB and TRS are always transmitted on the secondary cell for the purpose of time / frequency synchronization as described above, power consumption may be high in terms of signal transmission of the base station and reception complexity of the terminal. In particular, since the base station should periodically transmit signals such as SSB and TRS even when there is no data to be sent or received, power consumption may occur. Recently, energy saving of base stations has been considered important in wireless communication systems including 3GPP because it can contribute to building an environmentally friendly network by reducing carbon emissions and reducing operating expenses (OPEX) of operators in the communication industry. Therefore, due to the increased interest in base station energy saving, a new SI (study item) called "Network Energy Saving Study" was approved in 3GPP NR Release 18.

[0183] Therefore, hereinafter, the present disclosure proposes a method for reconstructing the signals required for time / frequency synchronization acquisition as densely as possible on the time axis. Thus, by reducing the synchronization acquisition process of the terminal, the terminal implementation complexity and terminal power consumption can be reduced. In addition, the base station can save the energy consumed by sending the signal required for the synchronization acquisition of the terminal. In addition, the signal required for the time / frequency axis synchronization acquisition includes the cell ID information of the serving cell, so that a cell discovery function can be provided. hereinafter, in the present disclosure, the signal set sent by the base station for time / frequency synchronization acquisition of the serving cell may be referred to as ES-DRS (energy-saving discovery signal). In addition, hereinafter, the present disclosure proposes a method for configuring an ES-DRS signal and a method for signaling an ES-DRS signal.

[0184] Fig.13 An example of a process for receiving a cell discovery signal in a wireless communication system according to an embodiment of the present disclosure is illustrated. Fig.13 The operation method of the terminal is illustrated.

[0185] Reference Fig.13 In step S1301, the terminal receives at least one SSB. The SSB is sent from the base station according to a predefined rule, and the terminal can attempt to receive the SSB based on the rule.

[0186] In step S1303, the terminal obtains synchronization using the synchronization signal. That is, the terminal can obtain time and / or frequency synchronization with the base station using the synchronization signal included in the received SSB.

[0187] In step S1305, the terminal obtains system information using the MIB. That is, the terminal can obtain the system information by decoding the MIB mapped to the broadcast channel included in the received SSB.

[0188] In step S1307, the terminal performs a random access procedure. The terminal may also obtain other system information (e.g., SIB) based on the system information obtained using the MIB. Then, the terminal may check the configuration information related to the random access channel indicated by the other system information, and perform the random access procedure based on the checked configuration information.

[0189] In step S1309, the terminal uses the reference signal multiplexed with the SSB to perform time and / or frequency tracking. According to various embodiments of the present disclosure, the SSB sent from the base station may be multiplexed with a reference signal. Here, the reference signal is used for time and / or frequency tracking and may be referred to as a TRS. Based on the multiplexing method, the terminal may determine the position of the reference signal from the position of the SSB and receive the reference signal. Using the reference signal, the terminal may estimate timing offset, delay spread, frequency offset, Doppler spread, etc.

[0190] Fig.14 An example of a process for transmitting a cell discovery signal in a wireless communication system according to an embodiment of the present disclosure is illustrated. Fig.14 An operation method of a base station is illustrated.

[0191] Reference Fig.14 In step S1401, the base station sends a burst including an SSB. Here, the SSB includes a synchronization signal and a broadcast channel, and the MIB is sent through the broadcast channel. In addition, in addition to the SSB, the burst may also include a TRS. According to various embodiments, the SSB and the TRS are multiplexed within the burst.

[0192] In step S1403, the base station sends at least one SIB. The at least one SIB includes system information other than the system information included in the MIB. For example, the at least one SIB may include configuration information for a random access channel.

[0193] In step S1403, the base station performs a random access procedure for the terminal. Specifically, the base station may perform the random access procedure by: receiving a random access preamble through a random access channel indicated by configuration information for a random access channel included in at least one SIB, sending a random access response, and performing subsequent signaling.

[0194] As described above, the base station may transmit a burst including SSB and TRS, and the terminal may receive a burst including SSB and TRS. The burst including SSB and TRS may be defined in various structures. Hereinafter, the present disclosure will describe a structure defined as a burst including SSB and TRS.

[0195] [Implementation #1] Method for configuring ES-DRS as a burst with TRS and SSB while maintaining the structure of SSB

[0196] According to embodiment #1 of the present disclosure, the SSB structure of the existing NR system is maintained, and at least one TRS can be set at the SSB symbol or neighbor symbol of the SSB. Even if the SSB sent on the secondary cell is sent at a frequency position other than the synchronization grid, a CD-SSB (cell-defined SSB) needs to be sent to support functions such as automatic neighbor relations (ANR) or cell global identity (CGI) reading. CD-SSB refers to an SSB that provides configuration information for a monitoring opportunity, in which a PDCCH including scheduling information for a PDSCH (physical downlink shared channel) carrying SIB1 can be sent. Here, the monitoring opportunity may represent a CORESET#0 and a type0-PDCCH CSS (common search space) set. Therefore, it is necessary to provide PBCH information for the SSB sent on the secondary cell.

[0197] As described above, due to the frequency band difference between the primary cell and the secondary cell, it is expected that when the terminal includes different RFs or different oscillators for the primary cell and the secondary cell, both the existing SSB and TRS structures will be required. Therefore, the present disclosure proposes an ES-DRS structure that maintains the SSB structure and allows TRS and SSB to be configured and sent as one burst. When SSB and TRS are configured as one burst, there is an advantage of reducing the energy consumption of the base station compared to the case where SSB and TRS are sent separately.

[0198] [Implementation #1-1] For the SSB and TRS constituting the ES-DRS, the SSB and TRS are configured as one burst by FDM (frequency domain multiplexing)

[0199] In the NR system, SSB consists of four OFDM symbols.

[0200] Fig.15 An example of multiplexing SSB and TRS (Tracking Reference Signal) in a wireless communication system according to an embodiment of the present disclosure is illustrated. Fig.15 Examples of SSB and TRS transmission structures are shown. Fig.15, the four OFDM symbols include symbol #n 1510, symbol #n+1 1520, symbol #n+2 1530, and symbol #n+3 1540. According to one embodiment, TRSs 912, 914, 942, and 944 may be placed at both ends of the frequency axis of the SSB of two symbols among the four OFDM symbols 910, 920, 930, and 940. Fig.15 In the case of the frequency axis of symbol #n 910 and symbol #n+3 930, TRS 912, 914, 942, and 944 are placed at both ends of the frequency axis of symbol #n 910 and symbol #n+3 930. However, according to another embodiment, TRS 912, 914, 942, and 944 may be placed at both ends of the frequency axis of symbol #n+1 920 and symbol #n+3 940, or at both ends of the frequency axis of symbol #n 910 and symbol #n+2 930.

[0201] [Embodiment #1-2] For the SSB and TRS constituting the ES-DRS, the SSB and TRS are subjected to FDM / TDM (time domain multiplexing) and configured as one burst

[0202] In the ES-DRS structure proposed in implementation #1-1, the interval between symbols where TRS is located can be up to 3 symbols. On the other hand, in the NR system, TRS is basically defined to be transmitted at intervals of 4 symbols. Therefore, in order to provide the same level of frequency axis synchronization acquisition accuracy as TRS with an interval of 4 symbols, an ES-DRS with a structure in which SSB and TRS are subjected to TDM / FDM is proposed.

[0203] The following [Table 7] illustrates a cell search procedure extracted from V17.2.0 of TS 38.213.

[0204] [Table 7]

[0205]

[0206]

[0207] In [Table 7], the transmission position within the time slot of each SCS of SSB (i.e., each case) can be as follows Fig.16 as shown in . Fig.16 The SSB transmission timing for each case in the wireless communication system according to the embodiment of the present disclosure is illustrated. Fig.16 , the implementation of the ES-DRS configuration for each case will be described as follows.

[0208] - Case A or Case C 1610: For SSB #n, the corresponding TRS can be sent in symbols #1 and #5 or symbols #2 and #6, and for SSB #n+1, the corresponding TRS can be sent in symbols #7 and #11 or symbols #8 and #12. In this way, the symbol interval between TRSs can be made the same as the symbol interval between TRSs in NR.

[0209] According to one embodiment, when TRS is transmitted in symbol #2 or symbol #8 which is a PSS symbol, 20 RBs occupied by PBCH or 12 RBs occupied by PSS in the symbol are cleared, and TRS may be discontinuously mapped on the frequency axis.

[0210] According to one embodiment, when TRS is transmitted in a symbol to which SSB is not mapped (e.g., symbol #1, symbol #6, symbol #7, or symbol #12), 20 RBs occupied by PBCH or 12 RBs occupied by PSS are cleared, and TRS may be mapped discontinuously on the frequency axis, or may be mapped continuously without gaps on the frequency axis.

[0211] According to one embodiment, when a TRS is transmitted in a PBCH symbol (eg, symbol #5 or symbol #11), 20 RBs occupied by the PBCH are cleared and the TRS may be discontinuously mapped on the frequency axis.

[0212] - Case B or Case D 1620: For SSB#n, the corresponding TRS may be transmitted in symbol#3 and symbol#7, for SSB#n+1, the corresponding TRS may be transmitted in symbol#8 and symbol#12, for SSB#n+2, the corresponding TRS may be transmitted in symbol#1 and symbol#5, and for SSB#n+3, the corresponding TRS may be transmitted in symbol#6 and symbol#10. In this way, the symbol interval between TRSs may be made the same as the symbol interval between TRSs in NR.

[0213] According to one embodiment, when TRS is transmitted in a PSS symbol (e.g., symbol #8 for SSB #n+1 or symbol #6 for SSB #n+3), 20 RBs occupied by PBCH or 12 RBs occupied by PSS may be cleared and the TRS may be mapped discontinuously on the frequency axis.

[0214] According to one embodiment, when TRS is transmitted in a symbol to which SSB is not mapped (e.g., symbol #3 for SSB#n, symbol #12 for SSB#n+1, symbol #1 for SSB#n+2, or symbol #10 for SSB#n+3), 20 RBs occupied by PBCH or 12 RBs occupied by PSS are cleared, and TRS can be mapped discontinuously on the frequency axis or continuously on the frequency axis without gaps.

[0215] According to one embodiment, when TRS is transmitted in a PBCH symbol (eg, symbol #7 for SSB #n, symbol #5 for SSB #n+2), 20 RBs occupied by PBCH are cleared and TRS may be mapped discontinuously on the frequency axis.

[0216] -Case E1630: Unlike other cases, in case E, since it is difficult to configure a TRS with an interval of 4 symbols for each SSB, the transmission interval of the TRS can be made to have an interval of 5 symbols. Specifically, for SSB#n, the corresponding TRS can be sent in symbols #6 and #11, for SSB#n+1, the corresponding TRS can be sent in symbols #7 and #12, for SSB#n+2, the corresponding TRS can be sent in symbols #5 and #10, and for SSB#n+3, the corresponding TRS can be sent in symbols #6 and #11. In this way, the symbol interval between TRSs can be made the same as the symbol interval between TRSs in NR. Similarly, for SSB#n+4, the corresponding TRS may be transmitted in symbol #2 and symbol #7, for SSB#n+5, the corresponding TRS may be transmitted in symbol #3 and symbol #8, for SSB#n+6, the corresponding TRS may be transmitted in symbol #1 and symbol #6, and for SSB#n+7, the corresponding TRS may be transmitted in symbol #2 and symbol #7. In this way, the symbol interval between TRSs can be made the same as the symbol interval between TRSs in NR.

[0217] According to one embodiment, when TRS is transmitted in a PSS symbol (e.g., symbol #12 for SSB #n+1, symbol #6 for SSB #n+3, symbol #8 for SSB #n+5, or symbol #2 for SSB #n+7), 20 RBs occupied by PBCH or 12 RBs occupied by PSS are cleared and TRS can be mapped discontinuously on the frequency axis.

[0218] According to one embodiment, when TRS is transmitted in a symbol to which SSB is not mapped (e.g., symbol #6 for SSB#n, symbol #7 for SSB#n+1, symbol #10 for SSB#n+2, symbol #11 for SSB#n+3, symbol #2 for SSB#n+4, or symbol #3 for SSB#n+5, symbol #6 for SSB#n+6, symbol #7 for SSB#n+7), 20 RBs occupied by PBCH or 12 RBs occupied by PSS are cleared, and TRS can be mapped discontinuously on the frequency axis or continuously without gaps on the frequency axis.

[0219] According to one embodiment, when TRS is transmitted in a PBCH symbol (e.g., symbol #11 for SSB#n, symbol #5 for SSB#n+2, symbol #7 for SSB#n+4, symbol #1 for SSB#n+6), the 20 RBs occupied by PBCH are cleared and the TRS can be mapped discontinuously on the frequency axis.

[0220] - Case F or Case G 1640: For SSB #n, the corresponding TRS can be transmitted in symbols #1 and #5 or symbols #2 and #6, and for SSB #n+1, the corresponding TRS can be transmitted in symbols #8 and #12 or symbols #9 and #13. In this way, the symbol interval between TRSs can be made the same as the symbol interval between TRSs in NR.

[0221] According to one embodiment, when TRS is transmitted in a PSS symbol (eg, symbol #2 or symbol #9), 20 RBs occupied by PBCH or 12 RBs occupied by PSS may be cleared and TRS may be discontinuously mapped on the frequency axis.

[0222] According to one embodiment, when TRS is sent in a symbol to which SSB is not mapped (e.g., symbol #1, symbol #6, symbol #8, symbol #13), 20 RBs occupied by PBCH or 12 RBs occupied by PSS are cleared, and TRS can be mapped discontinuously on the frequency axis or continuously without gaps on the frequency axis.

[0223] According to one embodiment, when a TRS is transmitted in a PBCH symbol (eg, symbol #5 or symbol #12), 20 RBs occupied by the PBCH are cleared and the TRS may be discontinuously mapped on the frequency axis.

[0224] According to the ES-DRS proposed in [Embodiment #1-2], one of the two symbols constituting the TRS can be FDMed with one of the four symbols constituting the associated SSB, and the remaining one symbol can be TDMed with the SSB.

[0225] In the above embodiment, the terminal may regard the TRS constituting the ES-DRS as being in a QCL relationship with the associated SSB multiplexed and transmitted. Specifically, the associated TRS and SSB may be in a QCL relationship in terms of gain, QCL-TypeA and QCL-TypeB attributes.

[0226] [Implementation #2] Signaling Method for ES-DRS Burst Structure

[0227] In the above implementation, the structure of the ES-DRS may be configured by high-level signaling (eg, cell-common RRC signaling, UE group-common RRC signaling, or UE-specific RRC signaling). The configuration parameters may include at least one of the following:

[0228] - Index of SSBs constituting ES-DRS

[0229] - The frequency axis position of the SSB constituting the ES-DRS (e.g., the center frequency of the SSB)

[0230] -Cell index or index list corresponding to ES-DRS

[0231] - Frequency axis resources of the TRS constituting the ES-DRS (e.g., starting RB index, number of RBs, RE index occupied by TRS within an RB)

[0232] - Timeline resource information (e.g., period, symbol index) of the TRS constituting the ES-DRS

[0233] -Power information of TRS constituting ES-DRS

[0234] In the signaling of the SSB index constituting the ES-DRS, similar to the notification of the SSB index actually sent in the NR system, the signaling of the timeline ES-DRS burst structure can be performed by notifying only the SSB index sent in the form of a bitmap (for example, ssb-PositionsInBurst in SIB1 or ServingCellConfigCommon). Alternatively, only the number of SSB indexes belonging to the ES-DRS may be signaled. In this case, the terminal can recognize that the SSB starts from the first position of the position defined in the standard, and the number of consecutive positioning is the same as the number of signaled notifications.

[0235] The base station can control the terminal to receive the ES-DRS corresponding to the cell index by indicating the specific cell index corresponding to the ES-DRS. Alternatively, for example, if the location of the terminal is not specific and the small cells are densely deployed, the base station can control the terminal to receive the ES-DRS corresponding to the cell index by notifying the terminal of multiple cell indexes or a list of cell indexes. Therefore, the terminal can add a cell corresponding to one of the notified cell indexes, perform measurements on one or more cells, and report them to the base station. In this way, if an ES-DRS structure corresponding to one or more cell indexes is signaled, information can be provided differently according to the cell index.

[0236] The frequency axis resources of the TRS constituting the ES-DRS can be determined based on the bandwidth of the active DL BWP of the corresponding serving cell of the terminal. For example, the TRS can be mapped from the starting RB of the active DL BWP to the last RB. Then, the terminal can receive configuration information about the frequency axis resources from the base station.

[0237] The TRS constituting the ES-DRS may be transmitted at the same period as the SSB each time, and may be transmitted at a period that is K times greater than the period of the SSB. For example, the period of the SSB may be set to 20 milliseconds, the period of the TRS may be set to 80 milliseconds, and in this case, the TRS may be transmitted once, and the SSB may be transmitted four times. At this time, the transmission period of the TRS may be set differently for each corresponding SSB index, and the presence or absence of the TRS may also be set differently for each SSB index. For example, the TRS corresponding to SSB index #0 is not set, the period of the TRS corresponding to SSB index #1 is set to 20 milliseconds, the same as the period of the SSB, and the period of the TRS corresponding to SSB index #2 may be set to 80 milliseconds. This is because the demand for TRS may be different between terminals receiving ES-DRS in the direction of the corresponding SS / PBCH index. For example, a terminal that does not support high-order modulation orders (such as 64 / 256-QAM) can operate without TRS.

[0238] Alternatively, on the contrary, the periodicity of the TRS constituting the ES-DRS can be set / sent shorter than the periodicity of the SSB. For example, compared with the SSB, the base station can support the acquisition of fine time / frequency axis synchronization of the terminal by operating the periodicity of the SSB as long as about 160 milliseconds and operating the periodicity of the TRS as short as about 20 milliseconds. In this case, the TRS and SS / PBCH can be multiplexed once every eight TRS transmissions.

[0239] Timeline resource information (such as symbol index of TRS constituting ES-DRS) can be pre-defined (by SCS of SSB) as the symbol position of [Implementation #1] mentioned above, or can be set by higher-layer signaling from the base station (e.g., cell-common RRC signaling, UE group-common RRC signaling, or UE-specific RRC signaling).

[0240] The power information of the TRS constituting the ES-DRS can be pre-defined / set to have the same power value as a specific signal of the SS / PBCH (e.g., PSS or SSS), or can be set separately by higher-layer signaling from the base station (e.g., cell-common RRC signaling, UE group-common RRC signaling, or UE-specific RRC signaling).

[0241] The technology proposed in the present disclosure may be associated with a DTX configuration or a DRX configuration. Here, a DTX configuration or a DRX configuration may be understood as a DRX configuration set for an idle / inactive terminal, a C-DRX configuration set for a connected terminal, or a configuration of a DTX and / or DRX mode in a cell-specific or UE group-common manner including a base station (hereinafter referred to as a "cell DTX / DRX configuration"). According to an embodiment, when there are multiple cell DTX / DRX configurations (e.g., DTX / DRX configuration #1 and DTX / DRX configuration #2), it may be configured whether to perform existing SSB and TRS transmission for each cell DTX / DRX configuration, or whether to multiplex SSB and TRS with the proposed ES-DRS structure. Alternatively, for a cell DTX / DRX configuration, it is possible to configure whether to perform the transmission of the existing SSB and TRS or whether to perform the transmission of the SSB and TRS multiplexed according to the proposed ES-DRS structure, depending on whether it is the DTX / DRX active time (e.g., the time period during which the onDurationtimer and / or inctivitytimer are operating, or the time period during which the terminal should wake up to transmit and / or receive). That is, in the DTX / DRX inactive time (which is a period different from the active time), the terminal can receive the multiplexed SSB and TRS according to the proposed ES-DRS structure.

[0242] Fig.17 An example of a process for signaling a structure of a cell discovery signal in a wireless communication system according to an embodiment of the present disclosure is illustrated. Fig.17 Signaling between the base station 1720 and the terminal 1710 for transmitting information on a multiplexing method of SSB and TRS is illustrated.

[0243] Reference Fig.17In step S1701, base station 1720 sends parameters related to the ES-DRS structure to terminal 1710. That is, as in the above-mentioned [Implementation #2], base station 1720 may notify terminal 1710 of the ES-DRS structure through high-layer signaling such as RRC signaling.

[0244] In step S1703, base station 1720 transmits an ES-DRS to terminal 1710. That is, as in the above-mentioned [Implementation #1], base station 1720 may transmit an ES-DRS. Terminal 1710 may receive an ES-DRS signal based on the configuration of the ES-DRS structure of base station 1720.

[0245] In step S1705, the terminal 1710 may use the ES-DRS to obtain time and / or frequency axis synchronization. By obtaining time / frequency axis synchronization of the corresponding serving cell, the terminal 1710 may perform efficient data transmission and reception. In addition, the base station may save energy by sending ES-DRS focused on the time axis.

[0246] As described above, the base station can assist the terminal in acquiring time and / or frequency synchronization by multiplexing SSB and TRS. According to one embodiment, when the environments of Pcell and Scell ​​are different from each other, a cell discovery signal including the above-mentioned SSB and TRS can be sent in one of Pcell and Scell. That is, in one of the carrier aggregation cells, the base station can send SSB and TRS through separate processes, or send SSB without TRS. However, the proposed technology is not limited to being applied to only some carrier aggregation cells, and the above-mentioned embodiment can be applied to the case where carrier aggregation is not configured, and the above-mentioned embodiment can be applied to cells in the same environment where carrier aggregation is configured.

[0247] 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).

[0248] 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.

[0249] Industrial Applicability

[0250] 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.

[0251] 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.

[0252] 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 at least one synchronization signal and a broadcast channel block (SSB); obtaining synchronization with a base station using a synchronization signal included in the SSB; obtaining system information using a master information block (MIB) included in the SSB; performing a random access procedure based on the system information; as well as Tracking is performed on at least one of time or frequency using a reference signal multiplexed with the at least one SSB on a time axis or a frequency axis.

2. The method according to claim 1, wherein: One SSB is multiplexed with a reference signal mapped to two symbols, and The two symbols include a first symbol and a fourth symbol occupied by the one SSB.

3. The method according to claim 1, wherein: The reference signal is mapped to a plurality of resource blocks (RBs) adjacent to a physical broadcast channel (PBCH) occupied by the one SSB in the fourth symbol, and is mapped to the plurality of RBs in the first symbol.

4. The method according to claim 1, wherein: One SSB is multiplexed with a reference signal mapped to two symbols. wherein the first symbol of the two symbols includes the first symbol or the fourth symbol occupied by the one SSB, and The second symbol of the two symbols includes a symbol not occupied by the one SSB.

5. The method according to claim 4, wherein: The symbols not occupied by the one SSB include symbols adjacent to the first symbol or the fourth symbol.

6. The method according to claim 4, wherein: The reference signal mapped to the second symbol is mapped to at least some of resource blocks (RBs) except for RBs occupied by a primary synchronization signal (PSS) of the one SSB.

7. The method according to claim 4, wherein: The reference signal mapped to the second symbol is mapped to at least some of resource blocks (RBs) except for RBs occupied by a physical broadcast channel (PBCH) of the one SSB.

8. The method according to claim 4, wherein: The reference signal mapped to the second symbol is mapped to consecutive RBs including the RB occupied by the one SSB.

9. The method according to claim 1, further comprising: Configuration information related to the reference signal and the structure of the at least one SSB is received.

10. The method according to claim 9, wherein: The configuration information includes at least one of the following items: information about the index of the SSB multiplexed with the reference signal, information about the frequency axis position of the SSB, information about the cell index of the SSB multiplexed with the reference signal, information about the frequency axis resources of the reference signal multiplexed with the SSB, information about the time axis resources of the reference signal multiplexed with the SSB, or information about the power of the reference signal multiplexed with the SSB.

11. A method for operating a base station in a wireless communication system, the method comprising: transmitting at least one synchronization signal and a broadcast channel block (SSB); transmitting a reference signal multiplexed with the at least one SSB on a time axis or a frequency axis; Sending system information related to random access channel; as well as A random access procedure is performed based on the system information.

12. The method according to claim 11, further comprising: Configuration information related to the structure of the reference signal and the at least one SSB is sent.

13. 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 at least one synchronization signal and a broadcast channel block (SSB); obtaining synchronization with a base station using a synchronization signal included in the SSB; obtaining system information using a master information block (MIB) included in the SSB; performing a random access procedure based on the system information; and Tracking is performed on at least one of time or frequency using a reference signal multiplexed with the at least one SSB on a time axis or a frequency axis.

14. 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: transmitting at least one synchronization signal and a broadcast channel block (SSB); transmitting a reference signal multiplexed with the at least one SSB on a time axis or a frequency axis; Sending system information related to random access channel; as well as A random access procedure is performed based on the system information.

15. 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 at least one synchronization signal and a broadcast channel block (SSB); obtaining synchronization with a base station using a synchronization signal included in the SSB; obtaining system information using a master information block (MIB) included in the SSB; performing a random access procedure based on the system information; and Tracking is performed on at least one of time or frequency using a reference signal multiplexed with the at least one SSB on a time axis or a frequency axis.

16. A non-transitory computer-readable medium storing at least one instruction, the non-transitory computer-readable medium comprising the at least one instruction executable by a processor, in, The at least one command control device is to: receiving at least one synchronization signal and a broadcast channel block (SSB); obtaining synchronization with a base station using a synchronization signal included in the SSB; obtaining system information using a master information block (MIB) included in the SSB; performing a random access procedure based on the system information; as well as Tracking is performed on at least one of time or frequency using a reference signal multiplexed with the at least one SSB on a time axis or a frequency axis.

Images