Method and apparatus for transmitting and receiving on-demand system information for low power communication

Abstract

Disclosed are a method and an apparatus for transmitting and receiving on-demand system information for low power communication. A method of a terminal comprises the steps of: receiving a first signaling message from a first cell; receiving a second signaling message from a second cell; performing a procedure for determining whether to transmit a WUS to the second cell on the basis of the first signaling message and the second signaling message; transmitting the WUS to the second cell in an uplink resource on the basis of a result of the determination procedure; receiving a response message to the WUS from the second cell; and receiving first system information of the second cell from the second cell.

Description

Method and device for transmitting and receiving on-demand system information for low-power communication

[0001] The present disclosure relates to low-power communication technology, and more particularly, to a technology for transmitting and receiving on-demand system information to reduce power consumption in a communication system.

[0002] The development of next-generation communication systems (e.g., new radio (NR) communication systems, sixth generation (6G) communication systems, etc.) is becoming increasingly important as infrastructure for the proliferation of diverse future convergence services. Next-generation communication systems can support not only conventional mobile communication frequency bands but also millimeter wave, terahertz, and upper-mid bands. These systems can support a wider range of performance indicators and scenarios than conventional communication systems (e.g., long-term evolution (LTE) communication systems). Consequently, the processing power of communication nodes in next-generation communication systems may be enhanced, but power consumption may increase to support this enhanced communication capacity. To achieve carbon neutrality and / or secure profitability for communication service providers, technologies for reducing the power consumption of communication nodes (e.g., base stations, terminals, etc.) may be necessary.

[0003] The purpose of the present disclosure to solve the above problems is to provide a method and device for transmitting and receiving on-demand system information to reduce power consumption in a communication system.

[0004] According to embodiments of the present disclosure for achieving the above object, a method of a terminal includes the steps of: receiving a first signaling message from a first cell; receiving a second signaling message from a second cell; performing a determination procedure for determining whether to transmit a wake-up signal (WUS) to the second cell based on the first signaling message and the second signaling message; transmitting the WUS to the second cell in an uplink resource based on a result of the determination procedure; receiving a response message for the WUS from the second cell; and receiving first system information of the second cell from the second cell, wherein the uplink resource is set based on the first signaling message, and the first system information includes at least a system information block 1 (SIB1).

[0005] The first signaling message may be included in the second system information of the second cell received from the first cell.

[0006] The second signaling message may be a payload included in a master information block (MIB) received from the second cell or included in a physical broadcast channel (PBCH) received from the second cell.

[0007] The second signaling message may include a codepoint of a field indicating the number of subcarriers between an RB (resource block) occupied by an SSB (synchronization signal block) received from the second cell and an RB boundary of the second cell.

[0008] The above judgment procedure may include a procedure for determining whether the second cell is transmitting the first system information.

[0009] The above first system information may be included in a physical downlink shared channel (PDSCH), and the terminal may monitor a physical downlink control channel (PDCCH) that schedules the PDSCH in a search space set.

[0010] The configuration information of the above search space set may be included in the MIB of the second cell together with the second signaling message, and the MIB may be transmitted from the second cell to the terminal.

[0011] The configuration information of the above search space set may be included in the second system information of the second cell together with the first signaling message, and the second system information may be transmitted from the first cell to the terminal.

[0012] The first system information may be received within a time window, and the time window may be determined based on configuration information included in the second system information of the second cell including the first signaling message.

[0013] The terminal can camp on the second cell based on the first system information regardless of the indication information of the access blocking field included in the MIB of the second cell.

[0014] According to embodiments of the present disclosure for achieving the above object, a method of a base station includes the steps of: transmitting a first signaling message to a terminal in a first cell of the base station; transmitting a second signaling message to the terminal in a second cell of the base station; receiving a wake up signal (WUS) from the terminal in an uplink resource of the second cell; transmitting a response message for the WUS to the terminal in the second cell; and transmitting first system information of the second cell to the terminal in the second cell, wherein the uplink resource is set based on the first signaling message, and the first system information includes at least SIB1 (system information block 1).

[0015] The first signaling message may be included in the second system information of the second cell transmitted from the first cell.

[0016] The second signaling message may be a payload included in a master information block (MIB) transmitted from the second cell or included in a physical broadcast channel (PBCH) transmitted from the second cell.

[0017] The second signaling message may include a codepoint of a field indicating the number of subcarriers between an RB (resource block) occupied by an SSB (synchronization signal block) transmitted from the second cell and an RB boundary of the second cell.

[0018] The above first system information may be included in a physical downlink shared channel (PDSCH), and a physical downlink control channel (PDCCH) that schedules the PDSCH may be transmitted in a search space set.

[0019] The configuration information of the above search space set may be included in the MIB of the second cell together with the second signaling message, and the MIB may be transmitted from the second cell to the terminal.

[0020] The configuration information of the above search space set may be included in the second system information of the second cell together with the first signaling message, and the second system information may be transmitted from the first cell to the terminal.

[0021] The first system information may be transmitted within a time window, and the time window may be determined based on configuration information included in the second system information of the second cell including the first signaling message.

[0022] According to embodiments of the present disclosure for achieving the above object, a terminal includes at least one processor, wherein the at least one processor causes the terminal to receive a first signaling message from a first cell; receive a second signaling message from a second cell; perform a determination procedure as to whether to transmit a WUS (wake up signal) to the second cell based on the first signaling message and the second signaling message; transmit the WUS to the second cell in an uplink resource based on a result of the determination procedure; receive a response message for the WUS from the second cell; and receive first system information of the second cell from the second cell, wherein the uplink resource is set based on the first signaling message, and the first system information includes at least SIB1 (system information block 1).

[0023] The first signaling message may be included in the second system information of the second cell received from the first cell.

[0024] According to the present disclosure, a first cell may periodically transmit system information, and a second cell may not periodically transmit system information to save power. If it is determined that the second cell does not periodically transmit system information, the terminal may transmit a signal requesting transmission of system information (e.g., a wake-up signal (WUS)) to the second cell. The second cell may receive the signal requesting transmission of system information from the terminal and transmit the system information to the terminal at the terminal's request. The terminal may receive system information from the second cell.

[0025] Figure 1 is a conceptual diagram illustrating embodiments of a communication system.

[0026] Figure 2 is a block diagram illustrating embodiments of the device.

[0027] Figure 3a is a conceptual diagram illustrating the first multiplexing pattern of SSB and CORESET.

[0028] Figure 3b is a conceptual diagram illustrating a second multiplexing pattern of SSB and CORESET.

[0029] Figure 3c is a conceptual diagram illustrating the third multiplexing pattern of SSB and CORESET.

[0030] Figure 4 is a conceptual diagram illustrating a first embodiment of an on-demand SIB1 transmission method.

[0031] FIG. 5 is a conceptual diagram illustrating a first embodiment of a preamble allocation method for UL WUS.

[0032] FIG. 6 is a conceptual diagram illustrating a second embodiment of a preamble allocation method for UL WUS.

[0033] FIG. 7 is a conceptual diagram illustrating a third embodiment of a preamble allocation method for UL WUS.

[0034] FIG. 8a is a conceptual diagram illustrating a first embodiment of a method for setting up UL WUS resources including a first resource.

[0035] FIG. 8b is a conceptual diagram illustrating a second embodiment of a method for setting up UL WUS resources including a first resource.

[0036] FIG. 9a is a conceptual diagram illustrating a first embodiment of a first resource setting method for asynchronous transmission.

[0037] FIG. 9b is a conceptual diagram illustrating a second embodiment of a first resource setting method for asynchronous transmission.

[0038] Fig. 10 is a conceptual diagram illustrating a first embodiment of a method for setting frequency resources of UL WUS.

[0039] Fig. 11 is a conceptual diagram illustrating a second embodiment of a UL WUS frequency resource setting method.

[0040] FIG. 12 is a flowchart illustrating a first embodiment of a random access method based on a conventional four-step RACH procedure.

[0041] Fig. 13 is a flowchart illustrating a first embodiment of a 4-step random access method based on UL WUS.

[0042] Fig. 14 is a conceptual diagram illustrating a second embodiment of a 4-step random access method based on UL WUS.

[0043] Fig. 15 is a conceptual diagram illustrating a third embodiment of a 4-step random access method based on UL WUS.

[0044] Fig. 16 is a conceptual diagram illustrating a fourth embodiment of a four-step random access method based on UL WUS.

[0045] Figure 17 is a flowchart illustrating a first embodiment of a random access method based on a conventional two-step RACH procedure.

[0046] Fig. 18 is a flowchart illustrating a first embodiment of a two-step random access method based on UL WUS.

[0047] Figure 19 is a flowchart illustrating a second embodiment of a two-step random access method based on UL WUS.

[0048] This disclosure may be subject to various modifications and various embodiments. Specific embodiments are illustrated and described in detail in the drawings. However, this is not intended to limit the disclosure to specific embodiments, but rather to encompass all modifications, equivalents, and alternatives falling within the spirit and technical scope of the disclosure.

[0049] While terms such as "first" and "second" may be used to describe various components, these components should not be limited by these terms. These terms are used solely to distinguish one component from another. For example, without departing from the scope of the present disclosure, a first component could be referred to as a "second component," and similarly, a second component could also be referred to as a "first component." The term "and / or" encompasses any combination of multiple related items or any one of multiple related items.

[0050] In embodiments of the present disclosure, “at least one of A and B” may mean “at least one of A or B” or “at least one of combinations of one or more of A and B.” Furthermore, in embodiments of the present disclosure, “at least one of A and B” may mean “at least one of A or B” or “at least one of combinations of one or more of A and B.”

[0051] When a component is referred to as being "connected" or "connected" to another component, it should be understood that it may be directly connected or connected to that other component, but that there may be other components intervening. Conversely, when a component is referred to as being "directly connected" or "connected" to another component, it should be understood that there are no other components intervening.

[0052] The terminology used in this disclosure is only used to describe specific embodiments and is not intended to limit the present disclosure. The singular expression includes the plural expression unless the context clearly indicates otherwise. In this disclosure, it should be understood that the terms "comprises" or "has" indicate the presence of a feature, number, step, operation, component, part, or combination thereof described in the specification, but do not preclude the presence or addition of one or more other features, numbers, steps, operations, components, parts, or combinations thereof.

[0053] Unless otherwise defined, all terms used herein, including technical or scientific terms, have the same meaning as commonly understood by a person of ordinary skill in the art to which this disclosure pertains. Terms defined in commonly used dictionaries should be interpreted as having a meaning consistent with their meaning in the context of the relevant technology, and shall not be interpreted in an idealized or overly formal sense unless explicitly defined herein.

[0054] Hereinafter, preferred embodiments of the present disclosure will be described in more detail with reference to the attached drawings. In order to facilitate an overall understanding in describing the present disclosure, identical reference numerals are used for identical components in the drawings, and redundant descriptions of identical components are omitted.

[0055] A communication system to which embodiments according to the present disclosure are applied will be described. The communication system may be a 4G communication system (e.g., a long-term evolution (LTE) communication system, LTE-A communication system), a 5G communication system (e.g., a new radio (NR) communication system), a 6G communication system, etc. The 4G communication system can support communication in a frequency band below 6 GHz, and the 5G communication system can support communication in a frequency band above 6 GHz as well as a frequency band below 6 GHz. The communication system to which embodiments according to the present disclosure are applied is not limited to the contents described below, and the embodiments according to the present disclosure can be applied to various communication systems. Here, the communication system may be used with the same meaning as a communication network, and “LTE” may indicate a “4G communication system,” an “LTE communication system,” or an “LTE-A communication system,” and “NR” may indicate a “5G communication system” or an “NR communication system.”

[0056] In an embodiment, “an operation (e.g., a transmission operation) is set to a communication node” may mean that “setting information for the operation (e.g., an information element, a parameter)” and / or “information instructing performance of the operation” are signaled to the communication node. In other words, “an operation (e.g., a transmission operation) is set to a communication node” may mean that the communication node receives “setting information for the operation (e.g., an information element, a parameter)” and / or “information instructing performance of the operation.” “An information element (e.g., a parameter) is set to a communication node” may mean “the information element is signaled to the communication node (e.g., the communication node receives the information element).” The signaling may be at least one of SI (system information) signaling (e.g., transmission of a system information block (SIB) and / or a master information block (MIB)), RRC signaling (e.g., transmission of RRC parameters and / or upper layer parameters), MAC CE (control element) signaling, or PHY signaling (e.g., transmission of DCI (downlink control information), UCI (uplink control information), and / or SCI (sidelink control information)).

[0057] In this disclosure, "time" may refer to a time point, and "time point" may refer to time. "Time" and "point point" may be used interchangeably. The reception time of a signal or channel may refer to the start time of reception or the end time of reception. The transmission time of a signal or channel may refer to the start time of transmission or the end time of transmission.

[0058] Figure 1 is a conceptual diagram illustrating embodiments of a communication system.

[0059] Referring to FIG. 1, the communication system (100) may include a plurality of communication nodes (110-1, 110-2, 110-3, 120-1, 120-2, 130-1, 130-2, 130-3, 130-4, 130-5, 130-6). In addition, the communication system (100) may further include a core network (e.g., a serving-gateway (S-GW), a packet data network (PDN)-gateway (P-GW), a mobility management entity (MME)). If the communication system (100) is a 5G communication system (e.g., a new radio (NR) system), the core network may include an access and mobility management function (AMF), a user plane function (UPF), a session management function (SMF), etc.

[0060] A plurality of communication nodes (110 to 130) can support a communication protocol (e.g., LTE communication protocol, LTE-A communication protocol, NR communication protocol, etc.) specified in the 3GPP (3rd generation partnership project) standard. The plurality of communication nodes (110 to 130) may support CDMA (code division multiple access) technology, WCDMA (wideband CDMA) technology, TDMA (time division multiple access) technology, FDMA (frequency division multiple access) technology, OFDM (orthogonal frequency division multiplexing) technology, Filtered OFDM technology, CP (cyclic prefix)-OFDM technology, DFT-s-OFDM (discrete Fourier transform-spread-OFDM) technology, OFDMA (orthogonal frequency division multiple access) technology, SC (single carrier)-FDMA technology, NOMA (non-orthogonal multiple access) technology, GFDM (generalized frequency division multiplexing) technology, FBMC (filter bank multi-carrier) technology, UFMC (universal filtered multi-carrier) technology, SDMA (space division multiple access) technology, etc. Each of the plurality of communication nodes may mean an apparatus or a device. The embodiments may be performed by a device or apparatus. The structure of the apparatus (e.g., device) may be as follows.

[0061] Figure 2 is a block diagram illustrating embodiments of the device.

[0062] Referring to FIG. 2, the device (200) may include at least one processor (210), a memory (220), and a transmission / reception device (230) that is connected to a network and performs communication. In addition, the device (200) may further include an input interface device (240), an output interface device (250), a storage device (260), etc. Each component included in the device (200) may be connected by a bus (270) and communicate with each other.

[0063] The processor (210) can execute program commands stored in at least one of the memory (220) and the storage device (260). The processor (210) may refer to a central processing unit (CPU), a graphics processing unit (GPU), or a dedicated processor in which the methods according to embodiments of the present disclosure are performed. Each of the memory (220) and the storage device (260) may be configured with at least one of a volatile storage medium and a non-volatile storage medium. For example, the memory (220) may be configured with at least one of a read-only memory (ROM) and a random access memory (RAM).

[0064] Referring again to FIG. 1, the communication system (100) may include a plurality of base stations (110-1, 110-2, 110-3, 120-1, 120-2) and a plurality of terminals (130-1, 130-2, 130-3, 130-4, 130-5, 130-6). Each of the first base station (110-1), the second base station (110-2), and the third base station (110-3) may form a macro cell. Each of the fourth base station (120-1) and the fifth base station (120-2) may form a small cell. The fourth base station (120-1), the third terminal (130-3), and the fourth terminal (130-4) may be within the cell coverage of the first base station (110-1). The second terminal (130-2), the fourth terminal (130-4), and the fifth terminal (130-5) may be within the cell coverage of the second base station (110-2). The fifth base station (120-2), the fourth terminal (130-4), the fifth terminal (130-5), and the sixth terminal (130-6) may be within the cell coverage of the third base station (110-3). The first terminal (130-1) may be within the cell coverage of the fourth base station (120-1). The sixth terminal (130-6) may be within the cell coverage of the fifth base station (120-2).

[0065] Here, each of the plurality of base stations (110-1, 110-2, 110-3, 120-1, 120-2) may be referred to as a NodeB (NB), an evolved NodeB (eNB), a gNB, an advanced base station (ABS), a high reliability-base station (HR-BS), a base transceiver station (BTS), a radio base station, a radio transceiver, an access point, an access node, a radio access station (RAS), a mobile multihop relay-base station (MMR-BS), a relay station (RS), an advanced relay station (ARS), a high reliability-relay station (HR-RS), a home NodeB (HNB), a home eNodeB (HeNB), a road side unit (RSU), a radio remote head (RRH), a transmission point (TP), a transmission and reception point (TRP), etc.

[0066] Each of the plurality of terminals (130-1, 130-2, 130-3, 130-4, 130-5, 130-6) may be referred to as a user equipment (UE), terminal equipment (TE), advanced mobile station (AMS), high reliability-mobile station (HR-MS), terminal, access terminal, mobile terminal, station, subscriber station, mobile station, portable subscriber station, node, device, on board unit (OBU), etc.

[0067] Meanwhile, each of the plurality of base stations (110-1, 110-2, 110-3, 120-1, 120-2) may operate in a different frequency band or may operate in the same frequency band. Each of the plurality of base stations (110-1, 110-2, 110-3, 120-1, 120-2) may be connected to each other via an ideal backhaul link or a non-ideal backhaul link, and may exchange information with each other via the ideal backhaul link or the non-ideal backhaul link. Each of the plurality of base stations (110-1, 110-2, 110-3, 120-1, 120-2) may be connected to the core network via the ideal backhaul link or the non-ideal backhaul link. Each of the plurality of base stations (110-1, 110-2, 110-3, 120-1, 120-2) can transmit a signal received from the core network to the corresponding terminal (130-1, 130-2, 130-3, 130-4, 130-5, 130-6), and can transmit a signal received from the corresponding terminal (130-1, 130-2, 130-3, 130-4, 130-5, 130-6) to the core network.

[0068] Additionally, each of the plurality of base stations (110-1, 110-2, 110-3, 120-1, 120-2) may support MIMO transmission (e.g., single user (SU)-MIMO, multi user (MU)-MIMO, massive MIMO, etc.), coordinated multipoint (CoMP) transmission, carrier aggregation (CA) transmission, transmission in an unlicensed band, device to device communication (D2D) (or, proximity services (ProSe)), Internet of Things (IoT) communication, dual connectivity (DC), etc. Here, each of the plurality of terminals (130-1, 130-2, 130-3, 130-4, 130-5, 130-6) can perform an operation corresponding to the base station (110-1, 110-2, 110-3, 120-1, 120-2) and an operation supported by the base station (110-1, 110-2, 110-3, 120-1, 120-2). For example, the second base station (110-2) can transmit a signal to the fourth terminal (130-4) based on the SU-MIMO scheme, and the fourth terminal (130-4) can receive a signal from the second base station (110-2) by the SU-MIMO scheme. Alternatively, the second base station (110-2) can transmit signals to the fourth terminal (130-4) and the fifth terminal (130-5) based on the MU-MIMO method, and each of the fourth terminal (130-4) and the fifth terminal (130-5) can receive signals from the second base station (110-2) based on the MU-MIMO method.

[0069] Each of the first base station (110-1), the second base station (110-2), and the third base station (110-3) can transmit a signal to the fourth terminal (130-4) based on the CoMP scheme, and the fourth terminal (130-4) can receive a signal from the first base station (110-1), the second base station (110-2), and the third base station (110-3) based on the CoMP scheme. Each of the plurality of base stations (110-1, 110-2, 110-3, 120-1, 120-2) can transmit and receive a signal with terminals (130-1, 130-2, 130-3, 130-4, 130-5, 130-6) within its cell coverage based on the CA scheme. Each of the first base station (110-1), the second base station (110-2), and the third base station (110-3) can control D2D between the fourth terminal (130-4) and the fifth terminal (130-5), and each of the fourth terminal (130-4) and the fifth terminal (130-5) can perform D2D under the control of the second base station (110-2) and the third base station (110-3).

[0070] The present disclosure may relate to a technology for transmitting and receiving signals in a communication system. More specifically, the present disclosure relates to a technology and device for performing signal transmission and beam management based on multiple transmission points in a communication system. The embodiments described below may be applied to a NR communication system, and may also be applied to other communication systems (e.g., an LTE communication system, a 5G (fifth generation) communication system, a 6G (sixth generation) communication system, etc.) in addition to the NR communication system.

[0071] In a communication system (e.g., NR communication system, 6G communication system), the numerology applied to the physical signal and channel can be variable. The numerology can be variable to meet various technical requirements of the communication system. In a communication system to which CP (cyclic prefix)-based OFDM waveform technology is applied, the numerology can include subcarrier spacing and CP length (or CP type). Table 1 may be a first embodiment of a numerology configuration for a CP-OFDM-based communication system. The subcarrier spacings can have a relationship of exponentiation of 2 with each other, and the CP length can be scaled at the same rate as the OFDM symbol length. At least some of the numerologies in Table 1 may be supported depending on the frequency band in which the communication system operates. In addition, the communication system may additionally support numerology(s) not listed in Table 1. Additional CP types (e.g., extended CP) not listed in Table 1 may be supported for specific subcarrier spacing (e.g., 60 kHz).

[0072]

[0073] Below, the frame structure of a communication system will be described. In the time domain, elements (e.g., resource elements) that constitute the frame structure may include subframes, slots, mini-slots, and symbols. A subframe may be used as a unit for transmission, measurement, etc., and the length of a subframe may have a fixed value (e.g., 1 ms) regardless of the subcarrier spacing. A slot may include consecutive symbols (e.g., 14 OFDM symbols). The length of a slot may be variable, unlike the length of a subframe. For example, the length of a slot may be inversely proportional to the subcarrier spacing.

[0074] A slot can be used as a unit for transmission, measurement, scheduling, resource configuration, timing (e.g., scheduling timing, hybrid automatic repeat request (HARQ) timing, channel state information (CSI) measurement and reporting timing, etc.). The length of the actual time resource used for transmission, measurement, scheduling, resource configuration, etc. may or may not match the length of the slot. A minislot can include consecutive symbol(s), and the length of a minislot can be shorter than the length of a slot. A minislot can be used as a unit for transmission, measurement, scheduling, resource configuration, timing, etc. A minislot (e.g., minislot length, minislot boundary, etc.) can be predefined in a technical specification. Alternatively, a minislot (e.g., minislot length, minislot boundary, etc.) can be configured (or instructed) to a terminal. It can be configured (or instructed) to a terminal that a minislot is used when a specific condition is satisfied.

[0075] A base station can schedule a data channel (e.g., a physical downlink shared channel (PDSCH), a physical uplink shared channel (PUSCH), a physical sidelink shared channel (PSSCH)) using some or all of the symbols constituting a slot. In particular, a data channel can be transmitted using a part of a slot for Ultra Reliable Low Latency Communication (URLLC) transmission, unlicensed band transmission, transmission in a situation where NR communication systems and LTE communication systems coexist, analog beamforming-based multi-user scheduling, etc. In addition, the base station can schedule a data channel using a plurality of slots. In addition, the base station can schedule a data channel using at least one mini-slot.

[0076] In the frequency domain, elements that constitute a frame structure may include resource blocks (RBs), subcarriers, etc. One RB may include consecutive subcarriers (e.g., 12 subcarriers). The number of subcarriers constituting one RB may be constant regardless of the numerology. In this case, the bandwidth occupied by one RB may be proportional to the subcarrier spacing of the numerology. An RB may be used as a transmission and resource allocation unit for data channels, control channels, etc. Resource allocation for a data channel may be performed in units of RBs or RB groups (e.g., resource block groups (RBGs)). One RBG may include one or more consecutive RBs. Resource allocation for a control channel may be performed in units of control channel elements (CCEs). In the frequency domain, one CCE may include one or more RBs.

[0077] In a communication system (e.g., an NR communication system), the unit time resource (hereinafter referred to as a "slot") described above may be composed of a combination of one or more of a downlink (DL) interval, a flexible interval (or an unknown interval), and an uplink (UL) interval. Each of the DL interval, the flexible interval, and the UL interval may be composed of one or more consecutive symbols. The flexible interval may be located between a DL interval and an UL interval, between a first DL interval and a second DL interval, between a first UL interval and a second UL interval, etc. When a flexible interval is inserted between a DL interval and a UL interval, the flexible interval may be used as a guard interval.

[0078] A slot may include one or more flexible periods. Alternatively, a slot may not include a flexible period. A terminal may perform a predefined operation in a flexible period. Alternatively, the terminal may perform an operation that is semi-statically or periodically configured by a base station in the flexible period. For example, the operation that is periodically configured by the base station may include a physical downlink control channel (PDCCH) monitoring operation, a synchronization signal block (SSB) reception and measurement operation, a CSI-RS (reference signal) reception and measurement operation, a DL SPS (semi-persistent scheduling) PDSCH reception operation, a sounding reference signal (SRS) transmission operation, a physical random access channel (PRACH) transmission operation, a periodically configured PUCCH transmission operation, a PUSCH transmission operation according to a configured grant (CG), etc. A flexible symbol may be overridden by a DL symbol or an UL symbol. When a flexible symbol is overridden by a DL symbol or an UL symbol, the terminal may perform a new operation instead of the existing operation on the flexible symbol (e.g., the overridden flexible symbol).

[0079] In the present disclosure, SSB may refer to a set of signals including a synchronization signal and / or a broadcast channel. The synchronization signal may include a primary synchronization signal (PSS), a secondary synchronization signal (SSS), etc., and the broadcast channel may include a physical broadcast channel (PBCH). The SSB may further include a reference signal. The reference signal (e.g., a reference signal included in the SSB) may refer to a demodulation reference signal (DM-RS), a CSI-RS, a tracking reference signal (TRS), a positioning reference signal (PRS), a phase tracking reference signal (PT-RS), etc. for decoding the PBCH. In an NR communication system, the SSB may refer to a synchronization signal / physical broadcast channel (SS / PBCH) block. The SSB may be transmitted periodically, and one or more SSB(s) may be repeatedly transmitted in one period.

[0080] The format of a unit time resource (hereinafter referred to as "slot format") can be semi-statically set by higher layer signaling (e.g., radio resource control (RRC) signaling). Information indicating a semi-static slot format can be included in system information, and the semi-static slot format can be set cell-specifically. In addition, the semi-static slot format can be additionally set for each terminal through terminal-specific higher layer signaling (e.g., RRC signaling). A flexible symbol of a cell-specifically set slot format can be overridden to a DL symbol or an UL symbol by terminal-specific higher layer signaling. In addition, the slot format can be dynamically indicated by physical layer signaling (e.g., a slot format indicator (SFI) included in downlink control information (DCI)). A semi-statically set slot format can be overridden by a dynamically indicated slot format. For example, a flexible symbol set to semi-fixed can be overridden by SFI to a DL symbol or an UL symbol.

[0081] A terminal can perform DL operation, UL operation, sidelink operation, etc. in a bandwidth part. A bandwidth part can be defined as a set of consecutive RBs (e.g., physical resource blocks (PRBs)) in a frequency domain having a specific numerology. One numerology can be used for signal transmission (e.g., transmission of a control channel or a data channel) in one bandwidth part. In the present disclosure, "signal" may mean any physical signal and channel when used in a broad sense. A terminal performing an initial access procedure can obtain configuration information of an initial bandwidth part from a base station through system information. A terminal operating in an RRC connected state can obtain configuration information of a bandwidth part from a base station through terminal-specific upper layer signaling.

[0082] The configuration information of the bandwidth portion may include information about the numerology and / or RB set applied to the bandwidth portion. At least one of the bandwidth portion(s) configured for the terminal may be activated. For example, one UL bandwidth portion and one DL bandwidth portion may each be activated within one carrier. In a time division duplex (TDD)-based communication system, a pair of UL bandwidth portions and DL bandwidth portions may be activated. The base station may configure multiple bandwidth portions for the terminal within one carrier and switch the active bandwidth portion of the terminal.

[0083] In embodiments, "a frequency band (e.g., a carrier, a bandwidth portion, a set of RBs, a listen before talk (LBT) subband, a guard band, etc.) is activated" may mean "a base station or a terminal is in a state where it can transmit and receive signals using the frequency band." In addition, "a frequency band is activated" may mean "a state where an RF (radio frequency) filter (e.g., a band-pass filter) of a transceiver is operating including the frequency band."

[0084] In embodiments, RB may mean CRB (common RB). Alternatively, RB may mean PRB or VRB (virtual RB). In a communication system (e.g., NR communication system), CRB may mean RB that constitutes a set of consecutive RBs (e.g., common RB grid) based on a reference frequency (e.g., point A). Carriers, bandwidth portions, etc. may be arranged on the common RB grid. In other words, carriers, bandwidth portions, etc. may be configured as CRB(s). RBs or CRBs that constitute bandwidth portions may be referred to as PRBs, and within bandwidth portions, CRB indices may be appropriately converted to PRB indices. In embodiments, RB may mean IRB (interlace RB).

[0085] The PDCCH can be used to transmit DCI or DCI formats to a terminal. The minimum resource unit constituting the PDCCH can be a resource element group (REG). For example, an REG can be composed of one RB in the frequency domain and one OFDM symbol in the time domain. DM-RS for decoding the PDCCH can be mapped to some of the REs constituting the REG, and control information (e.g., modulated DCI) can be mapped to the remaining REs. A PDCCH candidate can be composed of one CCE or aggregated CCEs. A CCE can be composed of multiple REGs. In an NR communication system, CCE aggregation levels 1, 2, 4, 8, and 16 can be supported, and a CCE can be composed of six REGs.

[0086] A CORESET (control resource set) may be a resource region in which a terminal performs blind decoding of a PDCCH. A CORESET may be composed of multiple REGs. A CORESET may be composed of one or more RBs in the frequency domain and one or more symbols (e.g., OFDM symbols) in the time domain. The symbols constituting a CORESET may be consecutive in the time domain. The RBs constituting a CORESET may be consecutive or non-contiguous in the frequency domain. One DCI (e.g., one DCI format, one PDCCH) may be transmitted within a CORESET. Multiple CORESETs may be configured from a cell perspective or a terminal perspective, and the time-frequency resource regions to which the multiple CORESETs are mapped may or may not overlap with each other.

[0087] A CORESET may be set in a terminal during the initial access procedure. For example, a CORESET may be set in a terminal by an initial access signal (e.g., PBCH or system information transmitted via PBCH). The ID (identifier) ​​of the CORESET set by the initial access signal may be 0. The CORESET set by the initial access signal may be referred to as CORESET 0. A terminal operating in an RRC idle state may perform a monitoring operation in CORESET 0 to receive the first PDCCH in the initial access procedure. Not only a terminal operating in an RRC idle state but also a terminal operating in an RRC connected state may perform a monitoring operation in CORESET 0. In addition to system information transmitted via an initial access signal (e.g., PBCH), a CORESET may be set in a terminal by other system information (e.g., SIB1 (system information block type 1)). For example, a terminal may receive SIB1 containing configuration information of CORESET for receiving a random access response (e.g., Msg2). CORESET may be configured in the terminal by terminal-specific higher layer signaling (e.g., RRC signaling).

[0088] A search space may refer to a set of candidate resource regions where PDCCHs can be transmitted. The UE may perform blind decoding on each PDCCH candidate within a predefined search space or a search space established by the base station. The UE may determine whether the PDCCH has been transmitted to itself by performing a cyclic redundancy check (CRC) on the blind decoding results. If the PDCCH is determined to be intended for the UE, the UE may receive the PDCCH.

[0089] One or more search spaces may constitute a search space set. The search spaces may be defined / configured for each CCE aggregation level, and the search space set may refer to a search space for each CCE aggregation level or a sum of search spaces for all CCE aggregation levels. For each CCE aggregation level, the PDCCH candidate may be composed of CCE(s) selected by a predefined hash function within a CORESET or a search space occasion. In an embodiment, the "search space set" may refer to a "search space."

[0090] A search space set can be logically associated (e.g., combined) with one CORESET. One CORESET can be logically associated with one or more search space sets. A common search space set configured via PBCH can be used to monitor a DCI scheduling a PDSCH for transmitting SIB1. The ID of the common search space set configured via PBCH can be set to 0. In other words, the common search space set configured via PBCH can be defined as a type 0 PDCCH common search space set or search space set #0. Search space set #0 can be logically associated with CORESET 0.

[0091] The search space set can be divided into a common search space set and a UE-specific search space set depending on the purpose or terminal operation. In the common search space set, common DCI or UE-specific DCI (e.g., UE-specific DCI) can be transmitted, and in the UE-specific search space set (e.g., UE-specific search space set), UE-specific DCI can be transmitted. For example, the common DCI can include resource allocation information of the PDSCH including system information, paging messages, etc., power control commands, slot format indicators (SFIs), and / or preemption indicators. The UE-specific DCI can include resource allocation information of the PDSCH and / or resource allocation information of the PUSCH. Depending on the purpose, multiple DCI formats can be defined, and the multiple DCI formats can be distinguished at the terminal by the DCI payload, DCI fields, DCI sizes, and / or radio network temporary identifiers (RNTIs).

[0092] In the present disclosure, a common search space may be referred to as a CSS (common search space), and a set of common search spaces may be referred to as a CSS set. A terminal-specific search space may be referred to as a USS (UE-specific search space), and a set of terminal-specific search spaces may be referred to as a USS set.

[0093] The terminal can assume that the PDCCH DM-RS has a QCL (quasi co-location) relationship with a signal (e.g., SSB, CSI-RS, PDSCH DM-RS, PDCCH DM-RS, etc.). The PDCCH DM-RS can refer to a DM-RS used for modulation and / or demodulation of the PDCCH. The PDSCH DM-RS can refer to a DM-RS used for modulation and / or demodulation of the PDSCH. Since the PDCCH has the same antenna port as the PDCCH DM-RS, the PDCCH and the PDCCH DM-RS can have a QCL relationship with each other. Through the QCL assumption, the terminal can obtain information about the large-scale propagation characteristics of the wireless channel experienced by the PDCCH and PDCCH DM-RS, and can utilize the large-scale propagation characteristics of the wireless channel for channel estimation, reception beamforming, etc. The QCL parameter may include at least one of a delay spread, a Doppler spread, a Doppler shift, an average gain, an average delay, or a spatial Rx parameter. The spatial Rx parameter may correspond to at least one characteristic of a receive beam, a receive channel spatial correlation, or a transmit / receive beam pair. The spatial Rx parameter may be referred to as "spatial QCL." The PDCCH may be used to mean including a PDCCH DM-RS. That the PDCCH has a QCL relationship with a certain signal may mean that the DM-RS of the PDCCH has a QCL relationship with the certain signal. A signal having a QCL relationship with the PDCCH or a resource of the signal may be referred to as a QCL source, a QCL source signal, a QCL source resource, etc.

[0094] PDCCHs transmitted in the same CORESET (e.g., a search space set corresponding to the same CORESET, a PDCCH monitoring occasion, etc.) may have the same QCL relationship. In other words, a unit of a set in which a UE assumes the same QCL may be a CORESET, and the QCL assumptions may be independent for each CORESET. In an embodiment, each of a QCL and a QCL source of a CORESET may mean the QCL and a QCL source of a PDCCH received through the corresponding CORESET. Exceptionally, different QCL assumptions may be applied to search space sets corresponding to a single CORESET. For example, a search space set for monitoring RA (random access)-RNTI (e.g., a type 1 CSS set) and a search space set other than the search space set may have different QCL relationships.

[0095] The QCL relationship or QCL assumption (e.g., QCL source, QCL type, etc.) of a CORESET can be determined by a predefined method. For example, a UE can assume that a PDCCH DM-RS received through a certain CORESET or a certain search space set has a QCL relationship with respect to an SSB and / or CSI-RS selected during an initial access or random access procedure and a predefined QCL type. A QCL type can mean a set of one or more QCL parameters. The QCL relationship or QCL assumption (e.g., QCL source, QCL type, etc.) of a CORESET can be signaled from a base station to a UE (e.g., RRC signaling, MAC (medium access control) CE (control element) signaling, DCI signaling, a combination of the above signaling, etc.). In other words, the base station can set a transmission configuration information (TCI) state for a CORESET to the UE. In general, a TCI state may include at least one of an ID of a signal having a QCL relationship with a DM-RS of a physical channel to which the TCI is applied (e.g., a PDCCH DM-RS) (e.g., a QCL source of the PDCCH DM-RS, a QCL source resource) or a QCL type for the signal. For example, a base station may configure one or more TCI state candidates for each CORESET to a terminal via RRC signaling, and may indicate (e.g., configure) one TCI state used for CORESET monitoring of the terminal among the one or more TCI state candidates via MAC signaling (or DCI signaling). If there is only one TCI state candidate configured by RRC signaling, the MAC signaling procedure (or DCI signaling procedure) may be omitted.The terminal can perform PDCCH monitoring and reception operations for the corresponding CORESET based on TCI state setting information received from the base station.

[0096] In the present disclosure, the TCI state may be conveniently referred to as TCI. While TCI may generally refer to a broad concept including a beam or signaling information corresponding to a beam, it may be conveniently used in the present disclosure in a meaning corresponding to a beam. DL TCI, or a TCI for DL ​​signal reception, may correspond to a reception beam, and UL TCI, or a TCI for UL signal transmission, may correspond to a transmission beam. A transmission beam may refer to spatial relation information, a transmission spatial filter, etc.

[0097] The present disclosure may relate to a method for improving power efficiency in a communication system. In other words, the present disclosure may relate to a method for improving power efficiency in a network. An idle base station can minimize the transmission of system information and maximize sleep time. Embodiments of the present disclosure may be applied to communication systems (e.g., 4G communication systems (e.g., LTE communication systems), 5G communication systems (e.g., NR communication systems), 6G communication systems, etc.).

[0098] A terminal may perform an SSB reception operation to camp on a cell or make an initial connection. The terminal may assume that SSBs are transmitted based on a default period (e.g., 20 ms (milliseconds)) during the initial cell search process. After the initial cell search process, the terminal may receive a setting for the SSB period value through system information or an RRC message. In an NR communication system, the maximum period value of SSBs may be 160 ms. Multiple SSBs may be repeatedly transmitted via multiple beams within one period, and the terminal may receive (e.g., attempt to receive) the multiple SSBs based on different receive beams (e.g., different QCL assumptions). The terminal may select one SSB with the best reception quality among one or more SSBs, and perform subsequent transmission and reception procedures based on the selected SSB (e.g., resources, beams, QCL assumptions, etc. of the selected SSB). The terminal may obtain some system information through the SSB. For example, SSB may include PBCH as one component, and the terminal may obtain MIB by receiving PBCH.

[0099] A terminal may receive additional system information (e.g., SIB1, SIB) from a base station in addition to some system information (e.g., MIB). For example, the terminal may monitor and receive a PDCCH including scheduling information of a PDSCH in a PDCCH search space set, and may receive a PDSCH including an SIB (e.g., SIB1). The additional system information (e.g., SIB1, SIB) may be transmitted periodically, identically or similarly to SSB transmission. For example, SIB1 may be transmitted at a period of 160 ms, and SIB1 may be repeatedly transmitted multiple times within each period. The period of SIB1 transmission, including repeated transmissions, may coincide with the period of SSB transmission. The above embodiment may mean that the terminal monitors a CORESET (hereinafter referred to as a first CORESET) to which a PDCCH search space set is mapped at the same period as SSB. For example, the first CORESET may be CORESET 0, and the PDCCH search space set associated with CORESET 0 may be a type 0 PDCCH CSS set.

[0100] The first CORESET and / or PDCCH search space set can be configured through some system information (e.g., MIB). For example, the MIB can include configuration information of CORESET 0 and a type 0 PDCCH CSS set, and the PDCCH can be monitored in the type 0 PDCCH CSS set. Since the SIB is cell-specific information, the configuration information for the SIB can be included in a common DCI (e.g., DCI format 1_0), and the common DCI can be transmitted via the PDCCH. The common DCI can have a CRC scrambled by an RNTI (e.g., SI (system information)-RNTI) predefined in the technical specification. The PDCCH and / or the PDSCH can be received based on a QCL relationship with the received SSB.

[0101] Fig. 3a is a conceptual diagram illustrating a first multiplexing pattern of SSB and CORESET, Fig. 3b is a conceptual diagram illustrating a second multiplexing pattern of SSB and CORESET, and Fig. 3c is a conceptual diagram illustrating a third multiplexing pattern of SSB and CORESET.

[0102] Referring to FIGS. 3A to 3C, the SSB and the CORESET can be multiplexed in several forms. The CORESET may refer to the first CORESET or the SIB1 CORESET. The SIB1 CORESET may be a CORESET in which a PDCCH scheduling SIB1 transmission is transmitted and received. In the embodiment of FIG. 3A, the CORESET may be TDM'd with the SSB corresponding to the CORESET. The PDSCH including SIB1 may be multiplexed with the SSB corresponding to the PDSCH based on one of TDM, FDM, or a "combination of TDM and FDM." The above-described multiplexing pattern may be referred to as the first multiplexing pattern. In the embodiment of FIG. 3B, the CORESET may be TDM'd with the SSB corresponding to the CORESET, and the SIB1 PDSCH may be FDM'd with the SSB corresponding to the SIB1 PDSCH. In other words, CORESET can be mapped to different symbols from SSB, and SIB1 PDSCH can be mapped to the same symbols as SSB. The above-described multiplexing pattern can be referred to as a second multiplexing pattern. SIB1 PDSCH can refer to a PDSCH through which SIB1 is transmitted and received. In the embodiment of FIG. 3c, CORESET and SIB1 PDSCH can be FDM'd with SSB corresponding to the CORESET and the SIB1 PDSCH. In other words, CORESET and SIB1 PDSCH can be mapped to the same symbols as SSB. The above-described multiplexing pattern can be referred to as a third multiplexing pattern. The multiplexing pattern supported by the terminal can be different depending on the frequency band or the subcarrier spacing applied to SSB and CORESET. The first multiplexing pattern can be used for a wider frequency range and / or various subcarrier spacings compared to the second and third multiplexing patterns.

[0103] Meanwhile, the number of terminals camping or connected to a cell may vary depending on the service area or time zone. For example, during the nighttime hours when all employees in an indoor office have left work, there may be no terminals camping in the cell (e.g., base station) corresponding to the indoor office area. The state of the base station or cell may be conveniently referred to as an idle state. According to the above-described method, the base station must periodically transmit additional system information (e.g., SIB1) in addition to the SSB even when in the idle state. In particular, if the SIB1 CORESET is configured based on the first multiplexing pattern, the base station must stay awake for a longer period of time to transmit SIB1, which may result in an unnecessary increase in the base station's power consumption. This scenario may be conveniently referred to as a single-cell scenario or the first scenario. In the first scenario, the cell may form its own unique coverage that does not overlap with the coverage of other cells. It may be difficult for a terminal to communicate with another serving cell within the coverage of the cell.

[0104] Conversely, the coverages of multiple cells may overlap. For example, in a heterogeneous network (HetNet) environment including macro cells and small cells, the coverage of the macro cell may overlap with the coverage of the small cells. The macro cell may serve as an anchor cell, providing stable coverage over a wide area. The small cell may be deployed within the coverage of the macro cell and may be used for the purpose of offloading and / or performance enhancement through multi-TRP cooperative transmission. The coverage of the small cell may overlap with the coverage of the macro cell. When there are no terminals camping on and / or connected to the small cell, the periodic transmission of SIB1 by the small cell may result in unnecessary power consumption. Unlike the first scenario, a terminal belonging to the small cell coverage or a terminal attempting to enter the small cell coverage may communicate with not only the small cell but also the macro cell. In this sense, the scenario may be conveniently referred to as a multi-cell scenario or a second scenario.

[0105] Based on the scenarios described above, methods for reducing power consumption by minimizing the transmission of system information by an idle base station or cell will be proposed in the present disclosure. According to the proposed method, the base station can suspend or omit the operation of transmitting system information in the cell when a predetermined condition is satisfied. The predetermined condition may include a case where it is determined that there are no terminals camping or connected to the cell. Based on the above-described operation, the cell can omit the operation of waking up from sleep mode to transmit system information, and can reduce power usage by maximizing the time it operates in sleep mode. When a terminal enters the cell area during a period in which the cell does not transmit system information, the terminal can request or trigger the cell (e.g., the base station managing the cell) to transmit system information to receive the system information. In other words, the system information in the cell can be transmitted aperiodicly upon the terminal's request. The above-described method may be referred to as a method of transmitting system information on-demand.

[0106] In the present disclosure, system information may mainly mean SIB1, and the proposed method may be referred to as an on-demand SIB1 transmission method. The methods according to the embodiments of the present disclosure may be applied in the same or similar form to other system information (e.g., other SIBs other than SIB1, SIBx, other system information (OSI), MIB, etc.) or other DL signals (e.g., SSB, CSI-RS, etc.) other than SIB1. x may be a natural number. In the embodiments of the present disclosure, the on-demand transmission signal described as SIB1 is merely an example, and it may also be interpreted as other system information (e.g., MIB, SIBx, OSI, etc.) other than SIB1 or other DL signals (e.g., SSB, CSI-RS, etc.). For example, a terminal may trigger SSB transmission to a base station or a cell based on the method described in the present disclosure, and may perform an operation of receiving an SSB transmitted based on the trigger and an operation after receiving the SSB. In the present disclosure, a terminal performing communication with a base station may mean a terminal in RRC idle mode or RRC inactive mode, but the proposed method may be applied identically or similarly to terminals in other states (e.g., terminals in RRC active mode).

[0107] In the present disclosure, a base station may refer to a base station that manages cell(s) or any cell(s) included in a base station. A cell may refer to a cell included in a base station or a base station that includes a cell (e.g., a base station that manages a cell). For example, when a terminal transmits and receives a signal to and from a cell, it may refer to the terminal transmitting and receiving a signal to and from a base station that includes the cell. The cell may refer to a cell that performs communication with the terminal, a cell on which the terminal has camped, a cell on which the terminal attempts initial connection, etc. For a terminal in RRC idle / inactive mode, a cell may refer to a cell on which the terminal has camped or a cell on which the terminal is likely to camp. For a terminal in RRC connected mode, a cell may refer to a serving cell, a neighboring cell, a cell that performs RRM (radio resource management) measurement, a cell on which the terminal has accessed, a cell on which the terminal maintains an access state, a carrier, etc.

[0108] In embodiments of the present disclosure, a cell performing an on-demand SIB1 operation (e.g., a transmission operation of an on-demand SIB1) may be a cell operating in a low-power mode, and a cell performing an on-demand SIB1 operation may be conveniently referred to as a network energy saving (NES) cell. When multiple cells exist, a first cell may refer to a cell that does not operate in a low-power mode (e.g., an anchor cell), and a second cell may refer to a cell that operates in a low-power mode (e.g., an NES cell). A cell that does not operate in a low-power mode (e.g., the first cell) may periodically transmit system information, and the on-demand SIB1 operation may not be applied to the first cell. The first cell and the second cell may belong to the same base station. Alternatively, the first cell and the second cell may belong to different base stations. In the second scenario, a cell that provides overlapping coverage with an NES cell and does not perform a low-power operation may be referred to as an anchor cell. For example, an anchor cell may periodically transmit SSB, SIB1, etc. In the present disclosure, when an anchor cell (e.g., a base station) periodically transmits SSB or SIB1, it may mean that a terminal performs an operation of periodically monitoring SSB or SIB1. The base station may omit SSB transmission in SSB resources that are periodically set as necessary. The base station may omit SIB1 transmission in SIB1 resources that are periodically set as necessary. A terminal that performs the operation described in the present disclosure may be conveniently referred to as a NES terminal.

[0109] [How to check whether SIB1 transmission has been performed]

[0110] Figure 4 is a conceptual diagram illustrating a first embodiment of an on-demand SIB1 transmission method.

[0111] Referring to FIG. 4, a base station can periodically transmit SSB in a cell. The base station can periodically transmit SIB1 together with SSB in the cell according to the method described above, and from a certain point in time, the base station can skip transmitting SIB1 and operate in a low-power mode. In other words, the cell can operate in a low-power mode. Alternatively, the base station can skip transmitting SIB1 in the cell from the time the cell is turned on and operate the cell in a low-power mode.

[0112] During a period in which the cell operates in low power mode, a terminal may enter a cell area. The terminal may be a terminal that has entered the coverage of the cell due to mobility. Alternatively, the terminal may be a terminal that first attempts to camp on the cell after powering on in the coverage of the cell. A terminal that has entered a cell may receive an SSB and perform a procedure for checking whether SIB1 is being transmitted from the cell. If the terminal determines that SIB1 is not being transmitted, the terminal may trigger SIB1 transmission to the cell. In other words, if the terminal determines that the cell does not periodically transmit SIB1, the terminal may trigger SIB1 transmission to the cell.

[0113] In the present disclosure, the operation of the terminal to check whether SIB1 transmission is performed may be replaced with a similar operation. For example, if the base station instructs the terminal to perform a SIB1 trigger operation for a cell, the terminal may trigger SIB1 transmission to the cell based on the instruction. The SIB1 trigger operation may refer to an operation of triggering SIB1 transmission. For another example, if the base station transmits information to the terminal indicating that the SIB1 trigger operation for a cell is permitted, the terminal may trigger SIB1 transmission to the cell based on the information. The SIB1 trigger operation (e.g., the SIB1 transmission trigger operation) may correspond to a UL WUS (wake-up signal) transmission operation described below. In other words, the signal instructing the SIB trigger operation may be a UL WUS. The UL WUS may be referred to as WUS for convenience. The terminal can implicitly determine whether the cell performs SIB1 transmission based on the signaling of the base station (e.g., signaling message(s) of the cell(s) belonging to the base station). The signaling operation of the base station and / or the SIB1 transmission operation corresponding to the signaling operation can be performed regardless of whether the cell transmits SIB1. For example, even if the cell periodically transmits SIB1, the terminal can trigger SIB1 transmission to the cell.

[0114] As a method for checking whether SIB1 is transmitted by an NES cell, a terminal can receive a signaling message from a base station. The signaling message can include a signaling message of the NES cell and / or a signaling message of another cell (e.g., an anchor cell). For example, the signaling message can be included in a MIB. The MIB can be a MIB of the NES cell, and the MIB can be transmitted from the NES cell to the terminal. The terminal can receive a PBCH from the base station (e.g., the NES cell) and check whether SIB1 is transmitted by the NES cell based on a specific field of the MIB included in the PBCH. To support the above operation, a specific field of the MIB, which has already been defined for a purpose, can be reused for the purpose of indicating whether SIB1 is transmitted.

[0115] For example, the MIB may include a field indicating PDCCH resources required for initial access (e.g., CORESET, search space set, PDCCH monitoring occasion, etc.). The terminal may reinterpret the bit values ​​of some codepoint(s) or some bit(s) of the field as corresponding to information indicating whether SIB1 is transmitted. For example, the purpose of the codepoint(s) indicating that there is no SIB1 corresponding to SSB among the codepoint(s) of the field and / or the codepoint(s) indicating the frequency position of the surrounding sync raster where the SSB is present may be changed to indicate whether SIB1 is transmitted. Similarly, the terminal may consider that SIB1 is not being transmitted in the NES cell if the field is set to a codepoint indicating that there is no SIB1. In the present disclosure, indicating that there is no SIB1 corresponding to the SSB may mean indicating that there is no CORESET 0 and / or Type 0-PDCCH CSS set corresponding to the SSB. The codepoint indicating that there is no SIB1 corresponding to the SSB may include a first codepoint and a second codepoint. The first codepoint may mean a codepoint indicating a frequency position of a peripheral synchronization raster in which the SSB corresponding to the SIB1 is transmitted, and the second codepoint may mean a codepoint indicating that there is no SSB corresponding to the SIB1 (or, SIB1 corresponding to the SSB) within a certain frequency range. A terminal that determines that the NES cell does not transmit SIB1 may regard the NES cell as operating in a low power mode, and may not perform or stop an operation of searching for a synchronization raster in the NES cell. Alternatively, the purpose of the LSB(s) or MSB(s) of the above field can be changed to indicate whether or not SIB1 is transmitted.The terminal can determine whether SIB1 is transmitted in the NES cell based on the changed code point(s) or the changed bit(s).

[0116] For another example, the MIB may include a field indicating a frequency offset (e.g., the number of subcarriers) between an SSB and an RB grid (or an RB boundary). For example, the frequency offset may be the frequency offset between an SSB transmitted by a NES cell (e.g., an RB with the lowest index occupied by the SSB, a center RB, or an RB with the highest index) and an RB boundary of the NES cell. A signaling message transmitted by a NES cell may include a frequency offset (e.g., a field indicating the frequency offset and / or a codepoint of the field). Similar to the above embodiment, a terminal may reinterpret the bit values ​​of some codepoint(s) or some bit(s) of the field as corresponding to information indicating whether or not SIB1 is transmitted. In other words, a legacy terminal may interpret the field according to its existing purpose, and a NES terminal may interpret the field in the above-described manner. The terminal operation for the first value of the above field (e.g., 30 or 14) may not be specified. Alternatively, the field may be set to a second value (e.g., 24 to 30 or 12 to 14), and the terminal may check a frequency value (e.g., a global synchronization channel number (GSCN)) to which a cell-defining SSB (CD-SSB) defining a cell is mapped based on the second value. When the field is set to the first or second value, the NES terminal may consider that the corresponding serving cell (e.g., the NES cell) does not transmit SIB1. When the field is set to a third value (e.g., 31 or 15), the NES terminal may consider that the corresponding serving cell (e.g., the NES cell) does not transmit SIB1. The SIB1 may be a periodically transmitted SIB1 or a regular SIB1. The above SIB1 may be a SIB1 other than an on-demand SIB1.

[0117] According to the above-described method, there may be restrictions on some settings by the MIB. For example, if a field indicating PDCCH resources for initial access and / or a field indicating a frequency offset between an SSB and an RB grid (or an RB boundary) is used to indicate whether SIB1 is transmitted, the indication of some codepoint(s) of the field(s) (e.g., codepoint(s) reinterpreted to indicate whether SIB1 is transmitted) may no longer be valid for the terminal. For example, a terminal that checks whether SIB1 is transmitted through the field(s) may not expect the field to indicate the absence of SIB1 or to indicate the frequency position of the neighboring synchronization raster. Conversely, a terminal that checks whether SIB1 is not present or to determine the frequency position of the neighboring synchronization raster through the field may not expect the field to indicate whether SIB1 is transmitted. For another example, a terminal (e.g., an NES terminal) that determines whether SIB1 is transmitted via a field indicating the frequency offset between the SSB and RB grid (or RB boundary) may receive an indication of a reduced range of frequency offsets than a terminal (e.g., a legacy terminal) that does not determine whether SIB1 is transmitted via the field. In other words, some frequency offset values ​​may not be valid for the NES terminal.

[0118] Alternatively, a spare bit included in the MIB may be used to indicate whether SIB1 is transmitted. The spare bit may include information indicating whether SIB1 is transmitted, and the terminal may determine whether SIB1 is transmitted based on the spare bit. The spare bit may consist of 1 bit. Alternatively, information on whether SIB1 is transmitted may be transmitted to the terminal through components of a PBCH other than the MIB (e.g., PSS, SSS, PBCH DM-RS, PBCH payload, etc.). In the present disclosure, the procedure for transmitting information to the terminal through the MIB may be interpreted in a broad sense, including the procedure for transmitting information to the terminal through the payload of the PBCH or the PBCH DM-RS.

[0119] The fields / code points / bits of the MIB whose purpose has been changed by the above-described method can be used for the above-described purpose (e.g., to indicate to NES terminals) in the section where SIB1 (e.g., SIB1 other than periodic SIB1, on-demand SIB1) is not transmitted. The fields / code points / bits whose purpose has not been changed by the above-described method can be used (e.g., to indicate to NES terminals and legacy terminals) in the section where SIB1 (e.g., SIB1 other than periodic SIB1, on-demand SIB1) is transmitted. The method based on the above-described spare bits can be regarded as a method in which the purpose of the spare bits is changed.

[0120] The signaling message may include explicit information. For example, a certain code point or a certain bit value (e.g., '1') may correspond to 'information indicating that SIB1 is transmitted', 'information indicating that SIB1 is to be received', etc. Conversely, another code point or another bit value (e.g., '0') may correspond to 'information indicating that SIB1 is not to be transmitted', 'information indicating that SIB1 is not to be received', etc. Alternatively, the signaling message may include implicit information. For example, a certain code point or a certain bit value may provide information necessary for a terminal to determine whether a resource of UL WUS, which will be described later, exists (e.g., whether a resource of UL WUS is valid, whether a resource of UL WUS is activated). As another example, a certain code point or a certain bit value may provide the terminal with information necessary for the terminal to determine whether to transmit or monitor a DL signal (e.g., PDCCH, PDSCH) including configuration information of UL WUS resources. The terminal can determine whether SIB1 is transmitted in the cell by an implicit method based on the above information. For example, the presence of UL WUS resources in the cell (e.g., UL UWS resources are valid, UL WUS resources are activated) can be interpreted to mean that SIB1 is not transmitted in the cell. The transmission of a DL signal (e.g., PDCCH, PDSCH, system information) for UL WUS resource configuration of the cell or the successful reception of the DL signal can be interpreted to mean that SIB1 is not transmitted in the cell. The DL signal can be transmitted from the cell (e.g., NES cell) or from a neighboring cell (e.g., anchor cell).

[0121] As another method for checking whether SIB1 is transmitted, the terminal can perform a blind detection (e.g., decoding) operation on a PDSCH including SIB1 (hereinafter referred to as SIB1 PDSCH) and / or a PDCCH scheduling SIB1 PDSCH (hereinafter referred to as SIB1 PDCCH), and can check whether SIB1 is transmitted based on whether the signal is detected. The blind detection operation can be performed based on a rule predefined in a technical specification or a rule set by a base station. For example, the time resource (e.g., time window, slot, symbol) for the terminal to monitor SIB1 PDCCH and / or SIB1 PDSCH, the number of blind detection attempts, and / or the number of blind detection failures can be predefined or set. The above-described operation can be performed on an NES cell. The terminal can perform a blind detection (e.g., decoding) operation on other signals that are not directly related to SIB1 reception. For example, the terminal may monitor a PDCCH / PDSCH other than the SIB1 PDCCH / SIB1 PDSCH in the type 0 PDCCH CSS set, and if the other PDCCH / PDSCH is successfully received, determine that SIB1 is not transmitted in the corresponding cell. The other PDCCH may be a PDCCH including UL WUS configuration information. Alternatively, the other PDCCH may be a PDCCH that schedules a PDSCH including the UL WUS configuration information. The other PDSCH may be a PDSCH including the UL WUS configuration information. Simultaneously or separately from the above-described embodiment, the other PDCCH may include a PDCCH having a CRC scrambled by an RNTI other than the SI-RNTI, a PDCCH including a DCI format other than DCI format 1_0, etc. The other PDCCH may be monitored in the same search space set as the SIB1 PDCCH.For example, the other PDCCH may be monitored in a type 0 PDCCH CSS set. The other PDSCH may be a PDSCH scheduled by the PDCCH. The above-described operation may be performed for a NES cell or a neighboring cell (e.g., an anchor cell). For example, the terminal may receive a PDSCH and / or a PDSCH (e.g., another PDSCH) including the UL WUS configuration information from a neighboring cell, and may determine that SIB1 is not transmitted in the NES cell based on the UL WUS configuration information. The UL WUS configuration information may include explicit information regarding whether the NES cell transmits SIB1.

[0122] The above-described method can be considered in both the first and second scenarios. In the second scenario, information regarding whether or not an NES cell transmits SIB1 can be signaled to a terminal from an anchor cell. For example, system information transmitted by a first cell (e.g., an anchor cell) can include information regarding whether or not a second cell (e.g., an NES cell), which is a neighboring cell, transmits SIB1. As described above, the information regarding whether or not an SIB1 is transmitted can correspond to UL WUS configuration information. The system information can be SIB1. Alternatively, the system information can be MIB or SIBx (x=2, 3, 4, ...). Alternatively, the system information can be system information defined separately from an SIB. The system information can be transmitted to a terminal via a PDCCH and / or a PDSCH. Information regarding whether or not an NES cell transmits SIB1 can be transmitted to a terminal together with information regarding a cell ID of the second cell. The terminal can obtain a cell ID during the process of receiving the SSB of the second cell, and after confirming that the obtained cell ID matches the cell ID received as part of the system information, can check whether the second cell has transmitted SIB1. The cell ID may mean a physical cell ID, a temporary identification number of the cell (e.g., a temporary mobile subscriber identity (TMSI)), etc.

[0123] The above-described methods may be implemented in combination. The terminal may determine whether the NES cell transmits SIB1 and / or whether the NES cell transmits UL WUS based on a plurality of signaling procedures. The plurality of signaling procedures may include at least a first signaling procedure and a procedure for signaling an MIB to the terminal. The first signaling procedure may refer to a procedure for signaling UL WUS configuration information and / or information regarding whether the SIB1 is transmitted to the terminal. In one embodiment, the first signaling procedure may be performed for a neighboring cell, and the MIB signaling procedure may be performed for the NES cell. In another embodiment, both of the signaling procedures may be performed for the NES cell.

[0124] The first signaling message transmitted by the anchor cell may include information on whether the NES cell transmits SIB1 and / or whether the NES cell transmits UL WUS, and the second signaling message transmitted by the NES cell may include information on whether the NES cell transmits SIB1 and / or whether the NES cell transmits UL WUS. The terminal may receive at least one of the first signaling message and the second signaling message, and may determine whether the NES cell transmits SIB and / or whether the NES cell transmits UL WUS based on information included in the at least one of the first signaling message and the second signaling message.

[0125] Whether to apply the reinterpretation method for a specific field of the above-described MIB may be determined based on whether the terminal receives UL WUS configuration information (or information regarding whether SIB1 is transmitted). For example, if the terminal receives UL WUS configuration information, the terminal may reinterpret specific codepoint(s) or bit(s) of the MIB based on the above-described method, and if the terminal does not receive UL WUS configuration information, the terminal may apply the conventional interpretation method to the codepoint(s) or bit(s). In other words, the reception operation of an SSB or MIB in an NES cell may be performed based on the operation of receiving an SIB from a neighboring cell.

[0126] For another example, the first signaling procedure may refer to a MIB signaling procedure. In one embodiment, information regarding whether SIB1 is transmitted may be signaled to the terminal based on both the reserved bits and existing fields of the MIB. Whether the reinterpretation method for a specific field of the MIB described above is applied may be indicated by the reserved bits of the MIB. In other words, the terminal may or may not reinterpret the existing field of the MIB using the above-described method, depending on the value of the reserved bit.

[0127] If it is indicated by the above-described method that SIB1 is not transmitted from the NES cell, the MIB included in the SSB transmitted from the NES cell may not indicate the CORESET #0 and / or Type 0-PDCCH CSS set corresponding to the SSB. For example, the terminal may ignore the field indicating the CORESET #0 and / or Type 0-PDCCH CSS set in the MIB. In this case, the terminal may receive the SIB1 of the NES cell from the neighboring cell and confirm the configuration of the CORESET #0 and / or Type 0-PDCCH CSS set of the NES cell through the SIB1. Alternatively, even if it is indicated by the above-described method that SIB1 is not transmitted from the NES cell, the terminal may still receive the configuration of the CORESET #0 and / or Type 0-PDCCH CSS set through the MIB. Some information necessary to confirm the resource location of the CORESET #0 and / or Type 0-PDCCH CSS set may be transmitted to the terminal from the neighboring cell. For example, the frequency position of CORESET #0 can be determined by a frequency offset (e.g., the number of subcarriers) between an SSB and an RB grid (or an RB boundary), and the frequency offset (e.g., the number of subcarriers) between the SSB and the RB grid (or the RB boundary) can be transmitted to the terminal by a signaling message from a neighboring cell rather than an MIB of the NES cell. For example, the signaling message can be a message including system information of the neighboring cell, a message including UL WUS configuration information of the NES cell, etc. The terminal can perform a PDCCH monitoring operation to receive a DL signal including SIB1, Msg2, etc. in the search space set.

[0128] Information regarding whether SIB1 is transmitted (or, an instruction for a SIB1 trigger operation, an instruction for a UL WUS transmission, whether the SIB1 trigger operation is permitted, whether the UL WUS transmission is permitted, etc.) obtained by the above-described method may be valid for a predetermined time period. The valid time period may refer to a time period in which the UL WUS transmission of the terminal is permitted or a time period in which the UL WUS transmission of the terminal is not permitted. Simultaneously with or separately from the above-described embodiment, the valid time period may refer to a time period in which the terminal assumes that SIB1 is transmitted or a time period in which the terminal assumes that SIB1 is not transmitted. For example, information regarding a time period in which SIB1 is transmitted and / or a time period in which SIB1 is not transmitted may be included in a signaling message transmitted from the base station to the terminal. The time period may be expressed as SSB period(s), SIB1 transmission period(s), or SIB1 PDCCH monitoring period(s). The time period may be determined based on a time point in time when the terminal acquires the signaling message. For example, the time interval may include a predetermined number of cycles starting from the SSB / SIB1 cycle to which the slot or symbol in which the terminal acquired the signaling message (e.g., MIB, SIB1, SIBx, other system information, etc.) belongs or the next cycle of the SSB / SIB1 cycle. The number of cycles may be predefined in the technical specification. Alternatively, the number of cycles may be included in the signaling message. Alternatively, the start time and / or duration of the time interval may be determined based on a reference time (e.g., a specific SFN (system frame number), a specific radio frame, etc.). The reference time may be determined based on a time at which the terminal receives the signaling message.For example, the above-described reference time may mean the most recent reference time before the time at which the terminal receives the signaling message. The time interval may be determined by a timer operation. For example, the terminal may start a timer in a slot, symbol, or SSB / SIB1 period in which the signaling message is received, and may consider SIB1 reception to be valid or invalid during the time interval in which the timer operates. The timer value may be decreased (e.g., decreased by 1) for each slot, symbol, or SSB / SIB1 period, and the timer may expire when the timer value becomes 0. Alternatively, the terminal may continuously apply the acquired information on whether or not the SIB1 has been transmitted until it additionally acquires the signaling message (e.g., until the signaling message is updated).

[0129] After the above validity period has elapsed, the terminal may perform an operation to check again whether SIB1 is transmitted. If the terminal fails to obtain information regarding whether SIB1 is transmitted (or, an instruction for a SIB1 trigger operation, an instruction for UL WUS transmission, whether SIB1 trigger operation is permitted, whether UL WUS transmission is permitted, etc.), the terminal may regard the corresponding cell (e.g., an NES cell) as a barred cell and may not attempt to access or camp on the cell. For example, when the terminal performs a cell selection / reselection operation, the cell may be excluded from candidate cells. Alternatively, if the terminal fails to obtain information regarding whether SIB1 is transmitted (or, an instruction for a SIB1 trigger operation, an instruction for UL WUS transmission, whether SIB1 trigger operation is permitted, whether UL WUS transmission is permitted, etc.), the terminal may assume that the corresponding cell (e.g., an NES cell) does not transmit SIB1 as a default state and may attempt UL WUS transmission for the cell.

[0130] Meanwhile, a terminal that has received information about whether the SIB1 is transmitted (or whether an instruction for a SIB1 trigger operation, an instruction for a UL WUS transmission, whether the SIB1 trigger operation is permitted, whether the UL WUS transmission is permitted, etc.) can consider that the corresponding cell (e.g., an NES cell) is not blocked. At this time, the indication information about whether the cell is access-blocked can be ignored. For example, even if the cell is indicated as being blocked by the MIB transmitted from the cell (e.g., an access-blocking bit included in the MIB) or the SIB for the cell (e.g., an access-blocking bit included in SIB1), the terminal can ignore the indication information and consider that the cell is not blocked. According to the above-described method, it may be unnecessary to define a separate cell access-blocking message for the NES terminal, and the information can be regarded as a cell access-blocking message for the NES terminal. By the above-described method, the base station can allow an NES terminal to access the NES cell while simultaneously blocking a legacy terminal from accessing the NES cell by using an existing cell access blocking message.

[0131] [How to set up UL WUS]

[0132] If it is determined that SIB1 is not transmitted in a cell by the above-described method, the terminal may request the cell to transmit SIB1. The terminal may trigger the SIB1 transmission by transmitting an UL signal to the cell. The UL signal may be referred to as a WUS in the sense that it triggers an operation of a base station (e.g., a cell) to exit a low power mode. The UL signal may be referred to as a UL WUS to distinguish it from a DL WUS. The UL signal may be referred to by a term other than UL WUS. The cell may be a NES cell. The terminal may transmit the UL WUS to the cell (e.g., an NES cell). Alternatively, the terminal may transmit the UL WUS to a cell other than the cell (e.g., an anchor cell). Although the present disclosure will primarily assume an "operation in which a terminal transmits a UL WUS to a NES cell," the proposed method may be applied to other cells (e.g., any cell) as well as an NES cell.

[0133] Below, methods for signaling UL WUS configuration information (e.g., UL WUS configuration information) to a terminal will be described. UL WUS configuration information may include information indicating UL WUS resources. UL WUS configuration information may further include additional information that defines the UL WUS transmission behavior of the terminal. UL WUS configuration information may be conveniently referred to as WUS configuration information.

[0134] In the first scenario, since the operation of transmitting the UL WUS by the terminal must be performed before the terminal receives the SIB1, the resources configured by the conventional SIB1 (e.g., the PRACH resources configured by the SIB1) may be difficult to use for the UL WUS. Therefore, the UL WUS configuration information may be transmitted to the terminal through a separate signaling procedure. For example, the UL WUS configuration information may be dynamically transmitted to the terminal based on the DCI. In other words, the UL WUS configuration information may be included in the DCI payload, and the DCI payload may be transmitted to the terminal via the PDCCH. Alternatively, the UL WUS configuration information may be included in the PDSCH, and the PDSCH may be dynamically scheduled by the DCI. The PDCCH and the PDSCH may be referred to as the first PDCCH and the first PDSCH, respectively, for convenience. The DCI may be referred to as the first DCI for convenience. Alternatively, the UL WUS configuration information may be referred to as SIB0 in the sense that it is system information transmitted at an earlier time than SIB1. In this case, the first PDCCH, the first PDSCH, and the first DCI may be referred to as SIB0 PDCCH, SIB0 PDSCH, and SIB0 DCI, respectively, for convenience. The entity transmitting the first PDCCH and / or the first PDSCH may be a NES cell. In the former case (for example, when the UL WUS configuration information is included in the DCI payload), the size of the UL WUS configuration information may be limited in order to maintain the DCI payload size at an appropriate level. For example, the payload size of the first DCI may not exceed the payload size of DCI format 1_0 and / or DCI format 0_0. Alternatively, the payload size of the first DCI may not exceed the maximum payload size allowed for the DCI format (for example, 128 bits).

[0135] The terminal may monitor the first PDCCH in a type 0 PDCCH CSS set. In other words, the first PDCCH and the SIB1 PDCCH may be monitored in the same search space set. The search space set may be set by an MIB (e.g., an MIB transmitted by an NES cell). Simultaneously or separately from the above-described embodiment, the search space set may be set in the terminal by system information transmitted from another cell (e.g., SIB1, MIB, SIBx transmitted by an anchor cell, other system information, etc.). The search space set ID of the search space set may be fixed to 0. According to one embodiment, the first PDCCH may be set to have the same DCI format (e.g., DCI format 1_0) as the SIB1 PDCCH. DCI format 1_0 of the first PDCCH and SIB1 PDCCH; DCI format 1_0 can be set to have the same payload size, and the terminal can monitor both the first PDCCH and the SIB1 PDCCH through one blind decoding.

[0136] The first PDCCH and the SIB1 PDCCH can be distinguished by different RNTIs. In other words, the operation of receiving UL WUS configuration information and the operation of receiving SIB1 can be distinguished by the RNTI during the DCI reception phase. The CRC of the first PDCCH can be scrambled by an RNTI other than the SI-RNTI. The other RNTI can be predefined as a fixed value in the technical specification. For example, the other RNTI can be defined as one of the reserved RNTI values ​​(e.g., one of the values ​​between hexadecimal FFF3 and FFFA). If the UL WUS configuration information is set as part of the DCI payload, the distinction operation by the RNTI can be necessarily performed at the terminal.

[0137] Alternatively, the CRC of the first PDCCH may be scrambled by the SI-RNTI. In this case, the first PDCCH may be distinguished from the SIB1 PDCCH by means other than the RNTI. For example, UL WUS configuration information may be included in the PDSCH and transmitted to the terminal, and the terminal may confirm that the configuration information included in the PDSCH is UL WUS configuration information through a higher layer (e.g., non-access stratum (NAS) layer, application layer) message included in the PDSCH. Alternatively, the first PDCCH and the SIB1 PDCCH may be configured with different DCI formats or DCI formats having different payload sizes. For example, the first DCI may be a DCI format other than DCI format 1_0. Simultaneously or separately from the above-described embodiment, the payload size of the first DCI may be different from the payload size of DCI format 1_0. The above DCI format 1_0 may have a payload size (e.g., a payload size corresponding to a fallback DCI) applicable for monitoring in a CSS set (e.g., a type 0 PDCCH CSS set).

[0138] Alternatively, the first PDCCH and the SIB1 PDCCH can be distinguished by a DCI field. For example, the first PDCCH and the SIB1 PDCCH can have the same DCI format, the same DCI size, and the same RNTI. The UE can receive the first DCI and determine whether the first DCI corresponds to the first PDCCH or the SIB1 PDCCH by interpreting a specific field (e.g., a one-bit indicator) included in the first DCI. The specific field can be defined using some of the reserved bits in the DCI payload.

[0139] The first PDCCH can be monitored periodically. Within the same cell, the terminal can monitor the first PDCCH with a period identical to the period of the SSB (e.g., period value). From the perspective of the base station, the SSB can correspond one-to-one with the first PDCCH. In other words, UL WUS configuration information corresponding to the SSB can be transmitted in every SSB transmission period. The terminal can monitor the first PDCCH with a period identical to the SSB period, and the base station can transmit the first PDCCH only in some periods. In other words, the base station can selectively transmit the first PDCCH. According to the above-described method, the delay time from the time when the terminal acquires the cell ID and DL synchronization based on the received SSB to the time when the terminal acquires the UL WUS configuration information can be minimized. For example, the terminal can receive both the SSB and the first PDCCH within the same SSB period. When UL WUS configuration information is included in the first PDSCH, the first PDSCH may be periodically transmitted together with the first PDCCH based on the method described above. To receive the first PDSCH, the terminal may receive one or more SSBs to obtain accurate DL synchronization.

[0140] Alternatively, the first PDCCH may be transmitted or monitored with a longer period (or shorter period) than the SSB. The monitoring period (e.g., period value) of the first PDCCH may be a multiple (or a divisor) of the SSB period. The period of the first PDCCH may be defined in the technical specification as a fixed value. Alternatively, the period of the first PDCCH may be signaled from the base station to the terminal. For example, the terminal may determine the transmission period of the first PDCCH based on the reserved bits included in the MIB. In another example, the terminal may determine the transmission period of the first PDCCH by reinterpreting the code point or bit value of a specific field of the MIB whose purpose has already been defined. To minimize the amount of message information, the period value in the signaling message may be expressed as a ratio of the period value of the first PDCCH to the period value of the SSB, or as a quotient obtained by dividing the period value of the first PDCCH by the period value of the SSB. For example, if the period value of the first PDCCH and the period value of the SSB are P1 and P2, respectively, the signaling message may indicate P1 / P2, P2 / P1, etc. In an embodiment, the period value of the first PDCCH may be a period value of a type 0 PDCCH CSS set.

[0141] In a second scenario, UL WUS configuration information may be transmitted to the terminal from a neighboring cell (e.g., an anchor cell). The anchor cell may be a cell on which the terminal is currently camping, and the terminal may receive the UL WUS configuration information, which is part of the system information transmitted by the anchor cell. For example, the UL WUS configuration information may be included in SIB1 or SIBx (x=2, 3, etc.), and a PDSCH including the UL WUS configuration information may be scheduled to the terminal via a DCI transmitted in a type 0 PDCCH CSS set. The DCI may be transmitted via a PDCCH that schedules the SIB1 PDCCH or the SIBx PDSCH, and the PDSCH may be the SIB1 PDSCH or the SIBx PDSCH. The above-described method may also be applied to the second scenario. For example, the DCI may be transmitted via the first PDCCH, and the PDSCH may be the first PDSCH. It may be difficult for a base station to detect when a terminal in RRC idle / inactive mode approaches a NES cell. Therefore, if the base station wishes to allow a terminal to camp on or initially access a NES cell, the base station may periodically transmit UL WUS configuration information for the NES cell through a cell (e.g., an anchor cell). For example, the DCI and / or the PDSCH may be periodically transmitted to the terminal.

[0142] For the purpose of improving resource efficiency, UL WUS configuration information may be transmitted aperiodically. Alternatively, for the purpose of improving resource efficiency, UL WUS configuration information may be transmitted at specific time intervals. For example, the terminal may perform a PDCCH monitoring operation for receiving UL WUS configuration information in the cell when a predetermined condition is satisfied. If the terminal confirms that SIB1 is not transmitted from the NES cell through the above-described method (e.g., MIB signaling, blind detection of SIB1, etc.), the terminal may expect that UL WUS configuration information is transmitted from the cell, and the terminal may perform an operation for receiving UL WUS configuration information in the cell. Simultaneously with or separately from the above-described embodiment, if a UL WUS trigger condition (e.g., a trigger condition for UL WUS transmission) is satisfied, the terminal may perform an operation for receiving UL WUS configuration information. Cases in which the above UL WUS trigger condition is satisfied may include "cases in which the terminal determines that a cell reselection procedure is being performed for an NES cell", "cases in which the quality of a DL signal measured by the terminal from the NES cell (e.g., reference signal received power (RSRP)) satisfies a reference value", etc. Information regarding a time period in which UL WUS configuration information is signaled may be shared between a base station (e.g., a cell) and the terminal according to a predetermined rule.

[0143] The above UL WUS configuration information may be transmitted together with the cell ID of the cell (e.g., NES cell) to which the terminal transmits the UL WUS. Configuration information of the cell (e.g., NES cell) required for the terminal to transmit the UL WUS to the cell (e.g., carrier, initial UL bandwidth portion, SSB resource, numerology, subcarrier spacing, SSB-RO connection relationship (e.g., SSB-RO mapping relationship), etc.) may be signaled to the terminal together with the UL WUS configuration information. The frequency positions of the carrier, the initial UL bandwidth portion, the SSB resource, etc. may be interrelated. For example, the carrier position may be indicated by an absolute radio frequency channel number (ARFCN), and the positions of the SSB resource and the initial UL bandwidth portion may be indicated by an offset from a starting point of the carrier bandwidth (e.g., RB offset). Alternatively, the SSB resource may be indicated by ARFCN, and the location of the carrier and the initial UL bandwidth portion may be indicated by an offset (e.g., RB offset) from the starting point of the SSB frequency resource. The frequency resource of the UL WUS may be indicated to the terminal by a relative distance from the frequency location of one of the SSB resource, the carrier, or the initial UL bandwidth portion.

[0144] Meanwhile, the UL WUS configuration of the NES cell may be changed or updated. In this case, the changed UL WUS configuration information (e.g., updated UL WUS configuration information) may be signaled to the terminal. The terminal camped on the NES cell may receive the changed UL WUS configuration information from the NES cell through the above-described method. To perform the above-described operation, the terminal may periodically monitor or receive the first PDCCH and / or the first PDSCH. Alternatively, the terminal camped on the NES cell may receive the changed UL WUS configuration information from a neighboring cell through the above-described method. To perform the above-described operation, the terminal may perform a procedure for camping on a neighboring cell and receive the UL WUS configuration information of the NES cell from the neighboring cell. After receiving the on-demand SIB1 of the NES cell, the terminal may perform a procedure for camping on the NES cell again if necessary. In other words, the terminal may perform a cell reselection procedure to receive updated UL WUS configuration information. Alternatively, the terminal may receive a DL signal (e.g., SIB1, SIBx, first PDCCH and / or first PDSCH) containing UL WUS configuration information from a neighboring cell while camping on the NES cell. The above operation may be performed when the above-described UL WUS trigger condition is satisfied.

[0145] A paging message may be used to notify a UE of a change (e.g., update) in UL WUS configuration information. The UE may periodically monitor a paging signal in an NES cell. The UE may receive a paging DCI (e.g., a DCI transmitted via a PDCCH having a CRC scrambled by a P(paging)-RNTI or a PEI (paging early indication)-RNTI). The UE may receive a paging PDSCH scheduled by the paging DCI as needed. The paging message may be included in the paging PDSCH. Alternatively, the paging message may be included in the payload of the paging DCI in the form of a short message. The paging message may include information indicating that UL WUS configuration information has been changed, information indicating that UL WUS configuration information will be received, etc. Based on the information included in the paging message, the UE may receive UL WUS configuration information from the NES cell or a neighboring cell according to the above-described method. The reserved bit(s) defined in the payload of the paging DCI may be utilized to indicate the above information. In an NR communication system, the paging DCI may have DCI format 1_0 and may be transmitted in a Type 2-PDCCH CSS set.

[0146] [How to configure UL WUS]

[0147] A terminal can trigger SIB1 transmission by transmitting an UL WUS to a cell (e.g., an NES cell). This operation can be performed after the terminal confirms that SIB1 is not transmitted in the cell (e.g., an NES cell). Alternatively, in some cases, the terminal can perform this operation regardless of whether SIB1 is transmitted in the cell (e.g., an NES cell). Methods for configuring UL WUS will be described below.

[0148] In the first method, the UL WUS may be a random access preamble, a signal identical to a random access preamble, or a signal similar to a random access preamble. The random access preamble, the signal identical to a random access preamble, and the signal similar to a random access preamble may be collectively referred to as a "random access preamble." The random access preamble may refer to a PRACH preamble, an RA preamble, etc. The random access preamble may be conveniently referred to as a preamble. In other words, the preamble may be interpreted as a random access preamble depending on the context. The resource through which the UL WUS is transmitted may be a PRACH resource, a resource having the same configuration as a PRACH resource, or a resource having a similar configuration to a PRACH resource. In the present disclosure, a PRACH resource, a resource having the same configuration as a PRACH resource, and a resource having a similar configuration to a PRACH resource may be collectively referred to as a "PRACH resource." The first method described above may be referred to as (method 100).

[0149] According to (Method 100), at least some of the PRACH preambles used for random access operation of a terminal may be used as UL WUS. The preamble may be generated based on a Zadoff-Chu (ZC) sequence having a length L. The preamble may be transmitted in a preset time-frequency resource region. The resource region in which the preamble is transmitted may be conveniently referred to as an RO (RACH occasion). Depending on the size of the RO, a long preamble or a short preamble may be used. A short preamble may be used when the time resource of the RO is relatively small (e.g., when the time resource of the RO is within one slot, when the time resource of the RO is several symbol(s)). Depending on the PRACH format defining the RO, the preamble may be temporally repeatedly transmitted within one RO. In an unlicensed band, a separately defined preamble may be used in addition to the above preambles in consideration of the occupied channel bandwidth (OCB) requirement.

[0150] Unlike the random access procedure, if a terminal triggers SIB1 transmission via UL WUS, the operation for distinguishing the terminal, the operation for specifying the terminal, and / or the operation for transmitting a response signal to the distinguished terminal (e.g., a specified terminal) may not be necessary in the procedure after the UL WUS transmission. Therefore, if a terminal triggers SIB1 transmission using UL WUS based on PRACH preamble, a procedure for contention resolution may not be required. In other words, it may not be a problem for multiple terminals to transmit UL WUS using the same preamble on the same resource. The base station can transmit SIB1 in the corresponding cell (e.g., NES cell) if the preamble is successfully detected, regardless of the number of terminals that simultaneously transmitted the preamble.

[0151] According to an embodiment, only one preamble may be used for UL WUS. The one preamble may be selected from among PRACH preambles. The one preamble may be referred to as a UL WUS preamble. A terminal that wishes to transmit UL WUS may be a terminal in an RRC idle state or an RRC inactive state. Since a terminal in an RRC idle state or an RRC inactive state has not yet received SIB1, it may be difficult for it to know for which procedure (e.g., for which purpose) each PRACH preamble is allocated among a 4-step RACH procedure, a 2-step RACH procedure, a contention-free based RACH procedure, etc. Accordingly, the one preamble may be determined regardless of the set and number of PRACH preambles allocated for the 4-step RACH procedure, the set and number of PRACH preambles allocated for the 2-step RACH procedure, the set and number of PRACH preambles allocated for the contention-free based RACH procedure, etc. For example, when the number of PRACH preambles is M, the one preamble (e.g., UL WUS preamble) can be fixed as the first PRACH preamble (e.g., PRACH preamble with index 0) or the last PRACH preamble (e.g., PRACH preamble with index (M-1)). If the one preamble is the first PRACH preamble, the UE can use the one preamble not only for the SIB1 transmission trigger but also for the 4-step RACH procedure. Alternatively, the one preamble can be predetermined as any one of the M PRACH preambles. In yet another method, the one preamble can be configured from the base station to the UE as any one of the M PRACH preambles. M can be a natural number.

[0152] In another embodiment, a plurality of preambles may be used for UL WUS. Similar to the above-described embodiment, the plurality of preambles may be part of PRACH preambles. The plurality of preambles may refer to UL WUS preambles. The terminal may transmit the UL WUS to the base station based on the plurality of preambles. For example, the plurality of preambles may include a first preamble and a second preamble, and the first preamble and the second preamble may correspond to first information and second information that the terminal wishes to transmit to the base station, respectively. Alternatively, the first preamble and the second preamble may correspond to first content and second content of information that the terminal wishes to transmit to the base station, respectively. The terminal may inform the base station of the first information or the first content by transmitting the UL WUS using the first preamble. The terminal may inform the base station of the second information or the second content by transmitting the UL WUS using the second preamble. The above information may be UE assistance information. When the number of preambles is N, the preambles for UL WUS may be predetermined as the first N preambles or the last N preambles among the PRACH preambles. Alternatively, N preambles used for SIB1 transmission triggering among M PRACH preambles may be configured from the base station to the terminal. The N preambles may have consecutive preamble indices. In this case, the N preambles may be expressed by the index of the first preamble and the number of preambles. Alternatively, the N preambles may be expressed by the index of the first preamble and the index of the last preamble. Each of M and N may be a natural number.

[0153] Meanwhile, a UL WUS transmission operation based on multiple beams can be performed. SSB can be repeatedly transmitted based on multiple beams, and the transmission resources of the UL WUS can be configured with multiple ROs. The multiple ROs can be FDMed within the same symbol set. Alternatively, the multiple ROs can be TDMed to different symbol sets. In other words, the multiple ROs can be configured based on FDM and / or TDM. M preambles can be configured for each RO. One or multiple preambles selected from the M preambles in each RO can be used as the UL WUS.

[0154] ROs for SIB1 transmission triggering may have an association relationship with SSBs. In SSB-RO mapping, among the ROs constituting the PRACH resource (e.g., PRACH configuration), only ROs that satisfy a predetermined condition may have an association relationship with the SSB. An RO that satisfies the predetermined condition may be referred to as a valid RO. An RO that fails the validity check may be excluded from the SSB-RO mapping. Among the SSBs, only SSBs that satisfy the predetermined condition may have an association relationship with the RO. An SSB that satisfies the predetermined condition may refer to an SSB that is actually transmitted (hereinafter, referred to as an actual SSB). Specifically, an actual SSB may refer to an SSB that is actually transmitted and is indicated to a terminal, an SSB corresponding to an SSB resource associated with a PDSCH to which rate matching is applied, etc. A PDSCH to which rate matching is applied may be indicated to a terminal. For example, L SSB resources can be defined for SSB repetition transmission in a certain frequency band, and among the L SSB resources, M SSB resources or M SSBs corresponding to the M SSB resources can be indicated to the terminal as actual SSBs. Each of L and M can be a natural number. The relationship between M and L can be "1≤M≤L". The information can be signaled to the terminal through system information (e.g., SIB1) or a terminal-specific RRC message. In the present disclosure, the SSB may be referred to as an effective SSB for convenience. In the embodiments below, SSB and RO may mean an effective SSB and an effective RO, respectively. In the embodiments, the SSB may mean a CD-SSB.

[0155] In an embodiment, ROs and SSBs may correspond one-to-one. In this case, the number of ROs may match the number of SSBs. In another embodiment, one RO may correspond to A SSBs. A may be a natural number greater than or equal to 2. In this case, M preambles constituting one RO may be divided into A preamble groups, and each of the A preamble groups may correspond to each SSB. For example, when M=64, a preamble group including the first 64 / A preambles (e.g., a first preamble group) may be configured, and the first preamble group may be correlated with the first SSB among the A SSBs. Each preamble group composed of 64 / A preambles may correspond to a unique UL beam (e.g., UL TCI, transmission space correlation, etc.). When the number of ROs is R, a total of A×R preamble groups may be formed. The preamble(s) used for UL WUS can be determined by the method described above within each preamble group.

[0156] FIG. 5 is a conceptual diagram illustrating a first embodiment of a preamble allocation method for UL WUS.

[0157] Referring to FIG. 5, multiple ROs can be used for UL WUS transmission, and one RO can be correlated with two SSBs. In other words, A can be 2. The M preambles constituting the RO can be divided into a first preamble group including the first M / 2 preambles and a second preamble group including the last M / 2 preambles. When the number of ROs is R, a total of 2×R preamble groups can be configured in the above manner. The first preamble or the first N preambles within each preamble group (e.g., the first preamble group and the second preamble group) can be used as a preamble for UL WUS. Alternatively, the last preamble or the last N preambles within each preamble group (e.g., the first preamble group and the second preamble group) can be used as a preamble for UL WUS. Alternatively, the terminal may determine N preamble(s) for UL WUS within each preamble group based on configuration information (e.g., UL WUS configuration information) received from the base station. Each of M, R, and N may be a natural number.

[0158] FIG. 6 is a conceptual diagram illustrating a second embodiment of a preamble allocation method for UL WUS.

[0159] Referring to FIG. 6, identically or similarly to the first embodiment of FIG. 5, multiple ROs may be used for UL WUS transmission, and one RO may be interrelated with two SSBs. For example, A may be 2. The M preambles constituting each RO may be divided into two preamble groups, and the first N preamble(s) (or the last N preambles) within each preamble group may be designated as a preamble for UL WUS. Each of M and N may be a natural number.

[0160] The above ROs can be used for purposes other than SIB1 transmission triggering. After receiving SIB1, the UE can receive configuration information of ROs for a random access procedure from the base station. Alternatively, the UE can receive configuration information of ROs for a random access procedure from the base station during the process of entering RC active mode. ROs for a random access procedure and ROs for UL WUS transmission can overlap. In other words, ROs configured for the purpose of SIB1 transmission triggering can be shared for random access purposes. In the embodiment of FIG. 6, preambles included in each preamble group (e.g., M / 2 preambles) can be allocated for a 4-stage RACH procedure, a 2-stage RACH procedure, a contention-free RACH procedure, etc. For example, the earliest preambles in each preamble group can be used for a contention-based 4-stage RACH procedure. Same as or similar to the embodiment described above, the first N preamble(s) in each preamble group can be allocated for UL WUS. As a result, the preamble(s) for the RACH procedure and the preamble(s) for the UL WUS procedure can overlap. The UE can use the overlapping preamble(s) for both the UL WUS transmission operation and the PRACH transmission operation for random access. The mapping ratio between ROs and SSBs (e.g., A) can be set to the same value between the RO configuration for the UL WUS procedure and the RO configuration for the random access procedure. The method for aligning the A value can be applied when the ROs for the UL WUS and the ROs for the random access procedure overlap at least partially.

[0161] The above two operations can be performed for different stages of the initial access procedure of the terminal. For example, a terminal that has not yet received SIB1 from the cell may not perform a random access procedure and may transmit a preamble only for the purpose of triggering SIB1 transmission. On the other hand, a terminal that has received SIB1 from the cell may not perform the SIB1 trigger operation and may transmit a preamble only for the purpose of random access. The base station can distinguish the expected terminal operation based on the presence or absence of SIB1 transmission in the cell. Since SIB1 is a signal broadcast to unspecified terminals in the cell area, the probability of an incident in which multiple terminals transmit the same preamble for different purposes may be low. Therefore, even when the RO sharing method or the preamble sharing method based on the second embodiment (e.g., the second embodiment illustrated in FIG. 6) is used, ambiguity in the terminal operation at the base station can be avoided, and the camping procedure and the initial access procedure of the terminal can be performed stably. According to the above-described method, RO resources can be reused for multiple purposes, thereby increasing resource efficiency. When available UL resources are sufficient, ROs for UL WUS and ROs for random access procedures can be allocated separately to different resource regions without overlapping. The first embodiment of FIG. 5 can be interpreted as a case where ROs (or preambles) for UL WUS are allocated separately from ROs (or preambles) for random access procedures.

[0162] In another embodiment regarding the correlation between ROs and SSBs for UL WUS, B ROs may correspond to one SSB. For example, B may be a natural number greater than or equal to 2. In this case, B×M preambles configured for B ROs may form one preamble group, and each preamble group may correspond to each SSB. For example, M may be 64, and each preamble group may include B×64 preambles for B consecutive ROs. When multiple ROs are arranged on a time-frequency resource, the ROs may be first indexed in frequency order in the frequency domain, and then indexed in time order in the time domain. Consecutive ROs may mean ROs having consecutive indices. Same as or similar to the above-described embodiment, each preamble group may correspond to a unique UL beam (e.g., UL TCI, transmission spatial correlation, etc.). When the number of ROs is R, a total of R / B preamble groups can be set. The preamble(s) used for UL WUS can be determined within each preamble group by the method described above.

[0163] FIG. 7 is a conceptual diagram illustrating a third embodiment of a preamble allocation method for UL WUS.

[0164] Referring to FIG. 7, multiple ROs can be used for UL WUS transmission, and two ROs can be correlated with one SSB. For example, B can be 2. 2×M preambles for the ROs can form a first preamble group, and a total of R / 2 preamble groups can be formed in the same manner. The first preamble or the first N preambles of each preamble group (e.g., the first preamble group) can be used as a preamble for UL WUS. Alternatively, the last preamble or the last N preambles of each preamble group (e.g., the first preamble) can be used as a preamble for UL WUS. Alternatively, the terminal can determine N preamble(s) for UL WUS within each preamble group based on configuration information received from the base station (e.g., UL WUS configuration information). The above ROs can be used for random access procedures, and the preamble allocated for the UL WUS can be used repeatedly for random access purposes. The mapping ratio (e.g., B) between the ROs and the SSBs can be set to the same value between the RO configuration for the UL WUS and the RO configuration for the random access. The method for aligning the B value can be applied when the ROs for the UL WUS and the ROs for the random access procedure overlap at least partially.

[0165] The terminal can select one or more preamble(s) from among the UL WUS preamble(s) determined by the above-described method, and transmit the selected preamble(s) to the base station (e.g., cell). By transmitting the selected preamble(s), the terminal can request the base station to transmit SIB1 in the cell. For example, the terminal can select one preamble group (e.g., RO), and transmit the UL WUS preamble assigned to the selected preamble group (e.g., RO). The UL WUS preamble can be transmitted based on a transmission beam corresponding to a reception beam of an SSB that is interrelated with the preamble group (e.g., RO) corresponding to the UL WUS preamble. When multiple UL WUS preambles are assigned to the selected preamble group, the terminal can select a preamble corresponding to information to be transmitted to the base station (e.g., content of the information), and transmit the selected preamble to the base station. If the above information is determined at the physical layer of the terminal, the operation of selecting one of the multiple preambles may be performed at the physical layer of the terminal. Alternatively, the terminal may randomly select one of the multiple preambles or select one based on a predefined rule and transmit the selected preamble. In this case, the operation of selecting one of the multiple preambles may be performed at a higher layer of the terminal.

[0166] To further increase the sleep time of the base station, the UL WUS resource can be set to a longer period than the PRACH resource period. In other words, the period of the RO for UL WUS (hereinafter referred to as UL WUS RO) can be longer than the period of the RO for random access (hereinafter referred to as RA RO). In the proposed method, the period value of the UL WUS RO can be set to a multiple of the period value of the RA RO for the same terminal. According to the method, even if the period values ​​of the UL WUS RO and the RA RO are different, the UL WUS RO and the RA RO can be arranged to overlap periodically, and resource efficiency can be increased. According to the method, a random access procedure based on the UL WUS RO can be efficiently performed. The random access procedure based on the UL WUS RO will be described later.

[0167] Similar to the above-described embodiment, the UL WUS configuration information may be defined as a separate signaling message that is distinct from the PRACH configuration information. The PRACH configuration information may be a message transmitted to a legacy terminal. In a method different from the above-described method, the UL WUS configuration information may be included in the PRACH configuration information. The UL WUS configuration information may be a part of the PRACH configuration information. Alternatively, a message including the PRACH configuration information may be modified or extended, and the modified message (or extended message) may be transmitted for the purpose of indicating a UL WUS operation of the terminal. The UL WUS configuration information may be derived based on the PRACH configuration information. The above-described method may also be interpreted as the PRACH configuration information being included in the UL WUS configuration information, the PRACH configuration information being derived based on the UL WUS configuration information, etc. According to the above method, the UL WUS resource and the PRACH resource may be the same. In other words, the UL WUS resource and the PRACH resource may not be distinguished from each other. Alternatively, UL WUS resources and PRACH resources may overlap. If the UL WUS resource cycle and the PRACH resource cycle are different, the UL WUS resource and PRACH resource may overlap only for some cycles. The UL WUS resource may mean UL WUS RO, and the PRACH resource may mean RA RO.

[0168] The UL WUS resource configuration associated with the above PRACH configuration information may be effective in the second scenario. For example, the anchor cell may transmit at least a part of the SIB1 of the NES cell to the terminal. The PRACH configuration information included in the SIB1 of the NES cell may be transmitted to the terminal by the anchor cell, and the terminal may obtain information necessary for UL WUS transmission based on the PRACH configuration information. The UL WUS resource configuration method associated with the PRACH configuration information may also be used in the first scenario. For example, the PRACH configuration information of the NES cell may be included in the first PDSCH described above, and the first PDSCH including the PRACH configuration information may be transmitted to the terminal.

[0169] Similar to the above-described embodiment, the terminal may receive configuration information of a set of ROs, and each RO may include PRACH preambles. In other words, each RO may be associated with PRACH preambles. Alternatively, each preamble group corresponding to an SSB may include PRACH preambles according to the SSB-RO correlation. The PRACH preambles constituting each RO or each preamble group may include preamble(s) for a contention-based RACH procedure and preamble(s) for a non-contention-based RACH procedure. The PRACH preambles may include preamble(s) for a 4-stage RACH and preamble(s) for a 2-stage RACH. For example, similar to the second embodiment of FIG. 6, the PRACH preambles may be appropriately distributed for a contention-based 4-stage RACH, a contention-based 2-stage RACH, and / or a non-contention-based RACH. Information specifying the range of preambles for each purpose may be included in the PRACH configuration information.

[0170] Some of the PRACH preambles constituting the RO or preamble group may be configured as UL WUS preambles. In the proposed method, some of the PRACH preambles allocated for a specific RACH procedure may be reused as UL WUS preambles. For example, the first N preamble(s) (or the preamble(s) with the lowest index) and / or the last N preamble(s) (or the preamble(s) with the highest index) of the PRACH preambles may be used as UL WUS preambles. Alternatively, the UE may determine N preamble(s) among the PRACH preambles as UL WUS preambles based on configuration information received from the base station. The configuration information may be part of the PRACH configuration information. Alternatively, the configuration information may be transmitted to the UE together with the PRACH configuration information. For example, the specific RACH procedure may be a non-contention-based 4-step RACH procedure.

[0171] In an embodiment, the UL WUS preamble may not be configured separately, and all PRACH preambles configured by the PRACH configuration may be used for the UL WUS. For example, all PRACH preambles constituting each RO or each preamble group may be used for the UL WUS. In other words, the N may match the cardinality of the preamble group. Alternatively, all preambles allocated for specific RACH procedure(s) within the RO or preamble group may be used for the UL WUS. For example, all preambles configured for non-contention-based 4-stage RACH and / or non-contention-based 2-stage RACH may be used for the UL WUS. The UL WUS resource may not be configured separately, and the UL WUS may be transmitted in the RO(s) configured by the PRACH configuration information. The UE may select one of the plurality of preambles and transmit the selected preamble in the UL WUS resource. The above one preamble may be randomly selected, and the above one preamble may be determined (e.g., selected) by a higher layer of the terminal.

[0172] In another proposed method, the PRACH preambles and the UL WUS preamble(s) can be distinguished from each other within an RO or a preamble group. For example, an RO or a preamble group can include a first preamble subgroup for a non-contention-based 4-stage RACH procedure (or a non-contention-based 2-stage RACH procedure, a contention-based RACH procedure) and a second preamble subgroup for UL WUS. The first preamble subgroup and the second preamble subgroup can be relatively prime. Information specifying the range of the first preamble subgroup and information specifying the range of the second preamble subgroup can both be included in PRACH configuration information, and the PRACH configuration information can be signaled to the UE. Alternatively, information specifying the range of the second preamble subgroup can be configured as a separate message, and information specifying the range of the first preamble subgroup can be included in PRACH configuration information. The separate message can be signaled to the UE together with the PRACH configuration information. The above information (e.g., information specifying the range of the first preamble subgroup and information specifying the range of the second preamble subgroup) may be transmitted to the terminal through the same PDSCH or the same PDCCH.

[0173] According to the above-described method, a UL WUS resource may include one or more ROs. The UL WUS resource may further include an additional UL resource. In the following, the additional UL resource may be conveniently referred to as a first resource. A terminal may transmit information to a base station explicitly or implicitly through the first resource. The information may be conveniently referred to as first information. The first information may include terminal assistance information (e.g., UE assistance information). The terminal assistance information may be information that helps determine a SIB1 transmission operation of a cell (e.g., an NES cell). The terminal may generate terminal assistance information and transmit the terminal assistance information to the base station. For example, the terminal assistance information may be information regarding the reception quality of an SSB received by the terminal from the cell (e.g., RSRP, RSRQ (reference signal received quality), RSSI (received signal strength indicator), etc.). Alternatively, the terminal assistance information may include information about the number of SIB1 transmissions preferred (or required) by the terminal, the SIB1 monitoring period (or transmission period), some messages or parameter sets belonging to SIB1, the SIB1 reception beam (or the optimal SSB beam or SSB resource), etc. The base station may determine the SIB1 transmission operation of the cell based on the terminal assistance information received via UL WUS, and may resume SIB1 transmission in the cell based on the determined operation. For example, SIB1 may be transmitted periodically by the method described above.

[0174] A UL WUS resource may include one RO and one first resource. Alternatively, considering UL WUS transmission by multiple beams, the UL WUS resource may be configured to include R ROs and R first resources. Each RO may be correlated with one first resource, and the correlated ROs and first resources may be transmitted based on the same transmission beam (e.g., the same UL TCI, etc.). Alternatively, preamble groups constituting the RO(s) may be correlated with the first resources. For example, R ROs may include A×R preamble groups, and the A×R preamble groups may correspond one-to-one with A×R first resources. In other words, one RO may be correlated with multiple first resources, and the UL WUS resource may include R ROs and A×R first resources. For another example, R ROs may be composed of R / B preamble groups, and the R / B preamble groups may correspond one-to-one with R / B first resources. In other words, one first resource may be correlated with multiple ROs, and a UL WUS resource may include R ROs and R / B first resources. Each of A, B, and R may be a natural number.

[0175] FIG. 8a is a conceptual diagram illustrating a first embodiment of a method for setting up UL WUS resources including a first resource, and FIG. 8b is a conceptual diagram illustrating a second embodiment of a method for setting up UL WUS resources including a first resource.

[0176] Referring to FIGS. 8A and 8B , a UL WUS resource may include multiple ROs and multiple first resources. In the embodiment of FIG. 8A , the ROs and the first resource may be FDM'd on the same time resource (e.g., the same symbol(s)). In the embodiment of FIG. 8B , the ROs and the first resource may be TDM'd on different time resources (e.g., different symbols).

[0177] According to the first embodiment, since the UL WUS occupies relatively less time resources, resource efficiency and power efficiency of the base station and the terminal can be improved. In this case, information regarding a frequency offset between the frequency resources of the RO and the frequency resources of the first resource (e.g., RB offset, subcarrier offset) can be additionally included in the UL WUS configuration information (or PRACH configuration information). The UL WUS configuration information can mean UL WUS resource configuration information. According to the second embodiment, the flexibility of resource allocation for the ROs and the first resources can be increased. In this case, information regarding a time offset between the time resources of the RO and the time resources of the first resource (e.g., slot offset, symbol offset) can be additionally included in the UL WUS configuration information (or PRACH configuration information). The base station can select one of the multiplexing methods applied in the above embodiments and configure the UL WUS resource based on the selected method. Information regarding UL WUS resource configuration (e.g., UL WUS configuration information) can be signaled to a terminal by the above-described method, and the terminal can perform an operation of transmitting a preamble in a RO and / or an operation of transmitting a signal in a first resource associated with the RO based on the signaled information.

[0178] A first resource can be defined as a set of sequences. For example, the first resource can be an SRS resource. Alternatively, the first resource can be a physical channel. For example, the first resource can be a PUSCH or PUCCH. A link adaptation technique can be applied to the first resource composed of a physical channel. When a link adaptation technique is applied to the first resource, resource allocation flexibility and transmission reliability can be further guaranteed compared to sequence-based transmission. The first resource can be transmitted based on at least one of waveform schemes such as OFDM, DFT-S-OFDM, and a single carrier. For example, a base station can appropriately select a waveform scheme of the first resource and signal information about the selected waveform scheme to a terminal. The terminal can check the waveform scheme indicated by the signaling of the base station. The information about the waveform scheme can be included in the configuration information (or, UL WUS configuration information, PRACH configuration information) of the first resource.

[0179] Similar to the above-described embodiment, the first resource may be a PUSCH resource. In other words, the UL WUS resource may be configured to include RO(s) and PUSCH resource(s). The UE may receive resource allocation information and / or scheduling information required to transmit a PUSCH in the PUSCH resource from the base station by the above-described signaling method. The resource allocation information may include resource allocation information of the time domain and frequency domain of the PUSCH, a PUSCH repetition transmission type, a number of PUSCH repetition transmissions, a PUSCH DM-RS mapping type, etc. The scheduling information may include at least the number of transport layers of the PUSCH, a TB (transport block) size, an MCS, an RV (redundancy version), an NDI (new data indicator), an HARQ process ID, etc. Since the PUSCH is transmitted for a special purpose only during the camping phase or the initial access phase of the UE, a fixed HARQ process ID may be assigned to the PUSCH. Alternatively, the PUSCH may not be assigned a HARQ process ID. In this case, the PUSCH scheduling information may not include a HARQ process ID. The PUSCH may include a TB, and the TB may include first information. If the first information is generated or determined by a higher layer of the terminal, the first information may be included in the TB in the form of a MAC CE. Alternatively, the PUSCH may include a UCI, and the UCI may include the first information. In this case, the first information may be generated or determined by a physical layer of the terminal. The PUSCH resource may overlap with the MsgA PUSCH resource of a two-step RACH procedure. Alternatively, the PUSCH resource may overlap with the Msg3 PUSCH resource of a four-step RACH procedure.The first resource may include a plurality of PUSCH resources (e.g., a plurality of PUSCH occasions), and the plurality of PUSCH resources (e.g., the PUSCH occasions) may be allocated to a resource separate from the MsgA PUSCH resources or the Msg3 PUSCH resources. Alternatively, the plurality of PUSCH resources may partially or fully overlap with the MsgA PUSCH resources or the Msg3 PUSCH resources.

[0180] Since the UL WUS is transmitted before the terminal performs a random access procedure for a cell (e.g., an NES cell), the terminal can transmit the UL WUS to the cell before acquiring UL synchronization for the cell. In other words, the UL WUS can be transmitted asynchronously.

[0181] FIG. 9a is a conceptual diagram illustrating a first embodiment of a first resource setting method for asynchronous transmission, and FIG. 9b is a conceptual diagram illustrating a second embodiment of the first resource setting method for asynchronous transmission.

[0182] Referring to FIGS. 9A and 9B , the beginning of the first resource or the resource immediately preceding the first resource in the time domain may be set as a guard interval. The guard interval may be set in consideration of the propagation delay and delay spread values ​​between the cell and the terminal. In the embodiment of FIG. 9B , the end of the first resource or the resources adjacent to the first resource in the frequency domain may be set as a guard band. The guard band may be set at either or both ends of the frequency domain of the first resource. The guard band may serve to mitigate interference due to non-orthogonality with signals transmitted on adjacent frequencies. When the terminal transmits the UL WUS to trigger SIB1 transmission, there may be no or very few terminals connected to the cell, and the probability of a signal being transmitted in the adjacent frequency domain of the first resource set for the terminal may be low. In such cases, it may be unnecessary for the first resource to include a guard band or to be set together with a guard band. Therefore, as in the embodiment of FIG. 9B , the first resource may include only a guard interval without a guard band. In other words, the first resource can be set up with a guard interval and without a guard band.

[0183] The UL WUS can be transmitted in the UL bandwidth portion. For example, the UL WUS can be transmitted in the initial UL bandwidth portion. When a terminal transmits a UL WUS to a NES cell, it may be difficult for the terminal to receive SIB1 information including information regarding the initial UL bandwidth portion of the NES cell in advance. Therefore, a method of additionally including configuration information regarding the initial UL bandwidth portion in the UL WUS configuration information may be considered. The configuration information regarding the initial UL bandwidth portion may include at least information regarding the frequency range of the initial UL bandwidth portion (e.g., the start RB and the number of RBs, or the start RB and the end RB) and / or the numerology. The RB may be a CRB, and the numerology may include at least a subcarrier spacing. Meanwhile, in the second scenario, the SIB1 of the NES cell may be transmitted to the terminal from a neighboring cell (e.g., an anchor cell), and the terminal may determine the initial UL bandwidth portion of the NES cell before transmitting the UL WUS to the NES cell based on reception of the SIB1.

[0184] Fig. 10 is a conceptual diagram illustrating a first embodiment of a method for setting frequency resources of UL WUS.

[0185] Referring to FIG. 10, the frequency resources of the UL WUS can be determined based on the frequency position of the UL bandwidth portion (e.g., the initial UL bandwidth portion). For example, the starting point (e.g., the starting RB or the starting subcarrier) of the frequency resources of the UL WUS can be determined as a position shifted by a predetermined frequency offset (e.g., the RB offset or the subcarrier offset) from the starting point (e.g., the starting RB or the starting subcarrier) of the initial UL bandwidth portion. Information regarding the frequency offset can be included in UL WUS configuration information and / or PRACH configuration information, and information regarding the frequency offset can be transmitted to the terminal by the signaling method described above.

[0186] In the above embodiment, the UL WUS resource may mean an RO. Similar to the above embodiment, multiple ROs may be considered for multi-beam-based operation, and the multiple ROs may be mapped to different frequency domains. The frequency offset may be used to determine the frequency location of one RO forming the UL WUS resource. The one RO may be an RO mapped to the lowest frequency domain and / or an RO having the lowest index among the ROs forming the UL WUS resource. The frequency location of the RO(s) mapped to a different frequency domain from the RO may be expressed as an offset from the frequency resource of the RO, and the offset may be additionally signaled to the terminal.

[0187] The UL WUS resource may further include a first resource. Both the RO and the first resource may be included in the initial UL bandwidth portion. The first resource may be configured based on the subcarrier spacing of the initial UL bandwidth portion. For example, the first resource may be a PUSCH or a PUCCH, and PUSCH transmission or PUCCH transmission may be performed based on the subcarrier spacing. In the RO, a PRACH preamble may be transmitted based on the subcarrier spacing. The format of the PRACH may be limited to a specific format. For example, the specific format may be a short PRACH format (e.g., PRACH format A, B, C, etc.). A PRACH preamble having the specific format may be transmitted based on the subcarrier spacing of the initial UL bandwidth portion. A PRACH preamble that does not have the above-mentioned specific format may be transmitted based on a subcarrier spacing different from the above-mentioned subcarrier spacing, and the other subcarrier spacing may be separately signaled to the terminal or may be predefined in the technical specifications for each frequency band.

[0188] Meanwhile, the terminal can receive SIB1 from the cell after the above procedure and obtain configuration information of the initial UL bandwidth portion included in SIB1. The configuration information of the initial UL bandwidth portion set for UL WUS transmission and the configuration information of the initial UL bandwidth portion by SIB1 may be identical. In other words, the terminal may not expect the two initial UL bandwidth portions to be set differently. The initial UL bandwidth portion is only one configuration example, and the above-described concept may be generally applied to any configuration parameter included in the UL WUS configuration. In other words, when some configuration information (or configuration parameter) is included in both the UL WUS configuration and SIB1 and transmitted to the terminal, the first configuration value of the configuration information included in the UL WUS configuration and the second configuration value of the configuration information included in the SIB1 may be identical.

[0189] Alternatively, it may be permissible for a base station to configure the initial UL bandwidth portion by SIB1 for the same terminal differently from the initial UL bandwidth portion for UL WUS transmission. A terminal that has received configuration information for both bandwidth portions may apply the configuration information acquired later procedurally or temporally (e.g., the configuration information for the initial UL bandwidth portion by SIB1) and perform a UL transmission operation based on the applied configuration information. The initial UL bandwidth portion is only one configuration example, and the above-described concept may be generally applied to any configuration parameter included in the UL WUS configuration. In other words, when some configuration information (or configuration parameter) is transmitted to a terminal by being included in both the UL WUS configuration and SIB1, a first configuration value of the configuration information included in the UL WUS configuration and a second configuration value of the configuration information included in the SIB1 may be different. In this case, if SIB1 is received after UL WUS configuration (e.g., after SIB1 is received), the terminal may consider that the configuration information has a second configuration value included in SIB1 and may perform an operation according to the second configuration value. The terminal may consider that the configuration information has a first configuration value included in UL WUS configuration before receiving SIB1 and may perform an operation according to the first configuration value. In other words, the first configuration value may be overridden by the second configuration value in a specific operation section of the terminal. The priority of the second configuration value may be higher than the priority of the first configuration value. In other words, the second configuration value may be applied with priority over the first configuration value. According to the above method, a portion of the initial UL bandwidth set for UL WUS transmission may be used in a limited manner only for the above purpose.

[0190] Alternatively, UL WUS transmission may not depend on a portion of the UL bandwidth (e.g., an initial UL bandwidth portion).

[0191] Fig. 11 is a conceptual diagram illustrating a second embodiment of a UL WUS frequency resource setting method.

[0192] Referring to FIG. 11, a terminal can transmit an UL WUS to a cell without setting or relying on an initial UL bandwidth portion of the cell. The frequency resource of the UL WUS can be determined based on the frequency resource of a DL signal (e.g., SSB). For example, the starting point (e.g., starting RB or starting subcarrier) of the frequency resource of the UL WUS can be determined as a position shifted by a predetermined frequency offset (e.g., RB offset or subcarrier offset) from the starting point (e.g., starting RB or starting subcarrier) of the frequency resource of the SSB. Alternatively, the frequency resource of the UL WUS can be determined based on the frequency resource of a carrier (e.g., DL carrier, UL carrier). For example, the starting point of the frequency resource of UL WUS (e.g., the starting RB or the starting subcarrier) may be determined as a position shifted by a predetermined frequency offset (e.g., the RB offset or the subcarrier offset) from the starting point of the carrier bandwidth (e.g., the starting RB or the starting subcarrier). Information about the frequency offset may be signaled to the terminal. When the UL WUS resource includes multiple ROs, the frequency offset may mean a frequency offset for one RO.

[0193] In a TDD system, an UL WUS may be transmitted in an UL symbol and / or a flexible symbol. If an RO for an UL WUS overlaps with a DL symbol, the RO may be considered an invalid RO, and the UL WUS may not be transmitted in the RO. Configuration information of a TDD slot format may be included in SIB1, and a terminal may transmit a UL WUS before receiving information about a slot format (e.g., a TDD slot format) of a cell to which the UL WUS is to be transmitted. In the present disclosure, the configuration information of a TDD slot format may be assumed for a TDD cell (e.g., a cell supporting TDD). The configuration information of a TDD slot format may refer to configuration information of a general slot format, and the configuration information of a general slot format may be applied to an FDD cell. The terminal may consider that RO transmission is possible in all symbols of the cell. For example, the terminal may consider all symbols of the cell as flexible symbols. Alternatively, the terminal may consider all symbols of the cell to be UL symbols at least from the perspective of UL WUS transmission. All of the symbols may be symbols excluding symbols for specific purposes (e.g., symbols mapped to DL signals such as SSB, symbols with CORESET #0 set). All ROs forming UL WUS resources (or ROs that satisfy overlap avoidance conditions with some DL signals such as SSB) may be considered valid ROs.

[0194] Alternatively, SIB1 of the cell (e.g., an NES cell) may be transmitted to the terminal by another cell (e.g., an anchor cell). The configuration information of the TDD slot format of the cell (e.g., an NES cell) may be included in the UL WUS configuration information (or PRACH configuration information) and transmitted to the terminal. The UL WUS configuration information (or PRACH configuration information) may be transmitted from the anchor cell to the terminal. The terminal may determine the transmission direction of each symbol based on the configuration information of the received slot format (e.g., a TDD slot format) and may verify the validity of the RO(s) forming the UL WUS resource by the above-described method. Alternatively, the terminal may expect that all UL WUS ROs are arranged in UL symbols and / or flexible symbols. In this case, the RO validity check procedure may be unnecessary.

[0195] In the above embodiment, even if the UL WUS is transmitted without depending on the initial UL bandwidth portion or the TDD slot format, the UL WUS resource may be correlated with the initial UL bandwidth portion and / or slot format set by SIB1 thereafter. For example, the UL WUS resource may be included in the initial UL bandwidth portion set by SIB1. The UL WUS resource may be transmitted based on the numerology (e.g., subcarrier spacing) of the initial UL bandwidth portion set by SIB1. According to the above-described method, the UL operating frequency, RF / baseband filtering, waveform, numerology, etc. of the terminal can be equally applied to procedures before and after the terminal receives SIB1, and the implementation complexity of the terminal can be reduced. For another example, the RO(s) of the UL WUS resource may not overlap with the DL symbol of the slot format configured by SIB1, and the RO(s) of the UL WUS resource may be configured in the UL symbol and / or the flexible symbol. According to the above-described method, the configuration information of the slot format transmitted to the terminal by the UL WUS configuration may be identical to the configuration information of the slot format transmitted to the terminal by SIB1. The UL WUS resource (e.g., an effective UL WUS resource, an effective RO) may be determined based on the slot format configuration included in the UL WUS configuration. The above embodiment may have the same meaning as that the UL WUS resource is based on the slot format configuration included in SIB1.

[0196] In a UL WUS transmission method using a PRACH preamble, assuming that the transmission beam and the reception beam are properly aligned, a failure to receive the UL WUS preamble in a cell may be due to insufficient transmission power of the UL WUS preamble. Therefore, when the terminal retransmits the UL WUS preamble to the same cell, the transmission power can be increased by applying power ramping. When the UL WUS preamble is retransmitted multiple times, the transmission power can be gradually increased. The transmission power increment applied to each retransmission procedure can be predefined in the technical specification. Alternatively, the transmission power increment applied to each retransmission procedure can be included in the UL WUS configuration information (or PRACH configuration information), and the base station can transmit the UL WUS configuration information including the transmission power increment to the terminal. The terminal can receive the UL WUS configuration information including the transmission power increment from the base station.

[0197] According to the above embodiments, ROs for UL WUS can be correlated with valid SSBs (e.g., actual SSBs). The UE can transmit the UL WUS before receiving system information (e.g., SIB1) for the cell (e.g., NES cell). Therefore, the UE may not be able to derive the SSB-RO mapping relationship described above at the time of transmitting the UL WUS. Consequently, the UE may not be able to specify the UL WUS RO correlated with the SSB selected by the UE (e.g., valid SSB), and the UL WUS transmission operation of the UE may not be performed normally.

[0198] As a method for solving the above-described problem, the UL WUS configuration message (e.g., UL WUS configuration information) may further include information indicating valid SSB(s) of the corresponding cell (e.g., NES cell), information regarding an SSB-RO mapping ratio, etc. The valid SSB(s) may mean SSB(s) that are actually transmitted, SSB(s) that are indicated to be actually transmitted to the terminal, etc. The terminal may identify valid SSB(s) based on the received UL WUS configuration information, map valid RO(s) for UL WUS to the valid SSB(s), determine a UL WUS RO corresponding to a specific SSB of the terminal based on the SSB-RO mapping, and transmit a UL WUS preamble in the determined UL WUS RO. The terminal may expect that the information indicating valid SSB(s) identified based on the UL WUS configuration and the information indicating valid SSB(s) identified based on SIB1 are consistent with each other. UL WUS preamble may mean UL WUS (e.g., a preamble included in UL WUS).

[0199] Alternatively, SSB-RO mapping for UL WUS can be performed for all SSBs defined in the cell (e.g., L SSBs). L can be a natural number. The L SSBs can include invalid SSBs (e.g., SSBs that are not actually transmitted). The SSBs can be mapped to valid RO(s) for UL WUS. With the above-described method, the UE can determine the RO on which to transmit the UL WUS preamble without prior information about the valid SSBs, and the UL WUS can be transmitted normally. With the above-described method, it may be difficult for UL WUS ROs and ROs for the conventional PRACH procedure to efficiently coexist (or overlap) in the same time-frequency resource.

[0200] In another method than (Method 100), the UL WUS may be an SRS, a signal identical to an SRS, or a signal similar to an SRS. An SRS, a signal identical to an SRS, and a signal similar to an SRS may be collectively referred to as SRS. A UL WUS resource may be an SRS resource, a resource configured identically to an SRS resource, or a resource configured similarly to an SRS resource. An SRS resource, a resource configured identically to an SRS resource, and a resource configured similarly to an SRS resource may be collectively referred to as an SRS resource. In another method, the UL WUS may be a new UL signal rather than a conventional UL signal. A terminal in an RRC idle / inactive mode may transmit an SRS or the new UL signal to a cell at least for the purpose of SIB1 triggering. In this case, the detailed methods applied in (Method 100) may be equally applied. In other words, a UL WUS resource may be formed of a plurality of resources based on multiple beams, and the UL WUS resource may be configured to include the first resource. For example, the UL WUS resource may include SRS resource(s) and first resource(s). Alternatively, the UL WUS resource may include resource(s) for new UL signal(s) and first resource(s). The above-described correlation and multiplexing method between the RO and the first resource, the asynchronous transmission method of the first resource, the frequency resource configuration method of the UL WUS, etc. may be identically or similarly applied to UL WUS configuration based on the SRS or new UL signal.

[0201] [UL WUS-based random access procedure]

[0202] A UE may request a cell (e.g., an NES cell) to transmit SIB1 for at least two purposes. The first purpose may be for the UE to camp on the cell. The second purpose may be for the UE to make an initial connection to the cell. For the first purpose, the UE may perform DL measurement and paging operations based on cell configuration information included in SIB1. For the second purpose, the UE may attempt an RRC connection by performing a random access procedure based on cell configuration information included in SIB1. The UE may initiate a four-step or two-step random access procedure by transmitting a Msg1 PRACH or a MsgA PRACH to the cell after receiving SIB1.

[0203] In a UL WUS transmission method based on the PRACH preamble, the random access procedure described above can be further optimized. With the proposed method, the UL WUS can trigger not only SIB1 transmission in a cell but also the random access procedure. In other words, the UL WUS can simultaneously trigger SIB1 transmission and the random access procedure. The UL WUS can simultaneously perform the roles of SIB1 trigger and PRACH preamble. The proposed UL WUS-based random access procedure will be described below.

[0204] FIG. 12 is a flowchart illustrating a first embodiment of a random access method based on a conventional four-step RACH procedure.

[0205] Referring to FIG. 12, a terminal may receive SIB1 from a cell (e.g., a base station) after transmitting an UL WUS to the cell. The terminal may receive a random access response (RAR) as a response message to the UL WUS from the cell. After receiving SIB1 and / or RAR, the terminal may perform a four-step random access operation based on a legacy RACH procedure. For example, after receiving SIB1 and / or RAR, the terminal may transmit Msg1 PRACH to the cell. In other words, the random access procedure of the terminal may be separated from the SIB1 trigger operation and the SIB1 reception operation. According to the above method, UL WUS transmission and Msg1 PRACH transmission may be unnecessarily overlapped. Accordingly, the terminal may receive RAR twice.

[0206] Fig. 13 is a flowchart illustrating a first embodiment of a 4-step random access method based on UL WUS.

[0207] Referring to FIG. 13, a terminal may transmit an UL WUS to a cell (e.g., a base station). The terminal may enter a random access procedure at the same time as requesting SIB1 transmission. The terminal may expect to receive a response message to the UL WUS from the cell. Specifically, the terminal may expect to receive SIB1 and / or Msg2 (e.g., RAR) in response to the UL WUS. The step of transmitting and receiving SIB1 and / or Msg2 (e.g., RAR) may be regarded as the second step of a four-step RACH procedure. After receiving SIB1 and / or Msg2, the terminal may transmit an Msg3 PUSCH to the cell. According to the above operation, the Msg1 PRACH transmission procedure and / or the Msg2 reception procedure may be omitted, and the above-described unnecessary duplication problem may be resolved. The time required for the random access procedure may be shortened. As a method proposed for the above procedure, the terminal may expect to receive SIB1 and Msg2 in the RAR window. The above operation may be referred to as (method 200).

[0208] Fig. 14 is a conceptual diagram illustrating a second embodiment of a 4-step random access method based on UL WUS.

[0209] Referring to FIG. 14, a terminal may perform a PDCCH monitoring operation for receiving SIB1 and a PDCCH monitoring operation for receiving Msg2 within a RAR window. The PDCCH monitoring operation for receiving SIB1 within the RAR window may be performed based on SI-RNTI in a type 0 PDCCH CSS set. The PDCCH monitoring operation for receiving Msg2 may be performed based on RA-RNTI in a type 1 PDCCH CSS set. The terminal may expect that a type 0 PDCCH CSS set and a type 1 PDCCH CSS set are each configured within the RAR window. Both the SIB1 PDSCH and the Msg2 PDSCH may be scheduled by a downlink fallback DCI (e.g., DCI format 1_0). The terminal may monitor the DCI for scheduling the SIB1 PDSCH and the DCI for scheduling the Msg2 PDSCH, respectively. The above DCIs can be monitored in the same CORESET, and the above DCIs can be received in the same CORESET. In other words, the Type 1 PDCCH CSS set and the Type 0 PDCCH CSS set can be correlated with the same CORESET.

[0210] The RAR window may start after C1 subframe(s) (or slot(s)) from the subframe(s) (or slot(s)) in which the terminal transmits the UL WUS. C1 may be a natural number. The length of the RAR window may be determined by the timer initial value. The order in which SIB1 and Msg2 are transmitted within the RAR window may not be defined in the technical specification. The order in which SIB1 and Msg2 are transmitted within the RAR window may be changed according to the configuration of the search space sets corresponding to SIB1 and Msg2, the transmission order intended by the base station, etc. The on-demand SIB1 may be received at an earlier time than the RAR (for example, a slot before the slot in which the RAR is received). Alternatively, the on-demand SIB1 may be received at the same time as the RAR (for example, the slot in which the RAR is received). Alternatively, the on-demand SIB1 may be received at a later time than the RAR (e.g., a slot later than the slot in which the RAR is received). Msg2 may be transmitted at an earlier time (e.g., a slot) than SIB1 within the RAR window. In this case, the minimum information required for the UE to receive the Msg2 PDCCH and the Msg2 PDSCH (e.g., search space set configuration information, initial DL bandwidth partial information, PDSCH configuration information, etc.) may be transmitted to the UE together with the UL WUS configuration information (or PRACH configuration information). Alternatively, the minimum information required for the UE to receive the Msg2 PDCCH and the Msg2 PDSCH (e.g., search space set configuration information, initial DL bandwidth partial information, PDSCH configuration information, etc.) may be included in the UL WUS configuration information and transmitted to the UE. The minimum information required for the terminal to receive Msg2 PDCCH and Msg2 PDSCH (e.g., search space set configuration information, initial DL bandwidth partial information, PDSCH configuration information, etc.) can be signaled to the terminal from another cell (e.g., an anchor cell).When a SIB1 window is set, the SIB1 window may temporally overlap with the RAR window.

[0211] According to the above-described method, the amount of information in the UL WUS configuration message may increase, and the signaling overhead for UL WUS configuration may increase. As a method for solving the above problem, SIB1 may be transmitted to the terminal before Msg2 within the RAR window. After acquiring SIB1, the terminal may receive Msg2 PDCCH / PDSCH based on the configuration information included in SIB1. Considering the time required for the terminal to process the received SIB1 PDCCH / PDSCH and acquire SIB1, a minimum distance (e.g., C2 subframe(s), slot(s), symbol(s)) between the reception time of the SIB1 PDCCH / PDSCH and the reception time of the Msg2 PDCCH / PDSCH within the RAR window may be defined. For example, the operation of the terminal monitoring the Msg2 PDCCH and / or receiving the Msg2 PDSCH may be performed starting from C2 slot(s) (or symbol(s)) after the slot (or symbol) in which the SIB1 PDSCH is received. C2 may be a natural number.

[0212] In the embodiments described above and / or embodiments to be described later, SIB1 may be repeatedly transmitted. For example, SIB1 PDCCH and SIB1 PDSCH may be repeatedly transmitted a predefined number of times. Alternatively, SIB1 PDCCH and SIB1 PDSCH may be repeatedly transmitted a predefined number of times to a terminal through a signaling procedure. All repeatedly transmitted SIB1 PDCCHs and all repeatedly transmitted SIB1 PDSCHs may be transmitted within a RAR window. Alternatively, at least the first SIB1 PDCCH and at least the first SIB1 PDSCH may be transmitted within a RAR window. When SIB1 is repeatedly transmitted, the minimum distance between SIB1 and Msg2 may be interpreted based on the last SIB1 PDSCH that constitutes the repeated SIB1 transmission.

[0213] In the proposed method, if the terminal receives both SIB1 and Msg2, it can transmit Msg3 (e.g., Msg3 PUSCH) to the cell. If the terminal fails to successfully receive either SIB1 or Msg2 within the RAR window, it can retransmit the UL WUS (or PRACH preamble) instead of entering the Msg3 transmission phase. Similar to or similar to the above-described embodiment, power ramping can be applied to the retransmitted preamble, and a higher transmission power can be applied to the retransmitted preamble than the previous transmission.

[0214] In a modified method for (Method 200), the cell may transmit both SIB1 and Msg2 in response to receiving an UL WUS, and SIB1 and Msg2 may be transmitted in different time intervals. For example, Msg2 may be transmitted in a RAR window, and SIB1 may be transmitted in a separately defined interval. The separately defined interval may be referred to as a SIB1 window. The SIB1 window may mean a interval in which the terminal monitors and receives the SIB1 PDCCH. The SIB1 PDSCH may be transmitted within or outside the SIB1 window.

[0215] Fig. 15 is a conceptual diagram illustrating a third embodiment of a 4-step random access method based on UL WUS.

[0216] Referring to FIG. 15, a SIB1 window and a RAR window can be defined, and a terminal can receive a SIB1 PDCCH / PDSCH in the SIB1 window, and the terminal can receive a Msg2 PDCCH / PDSCH in the RAR window. At least one PDCCH monitoring occasion of a type 0 PDCCH CSS set can be arranged within the SIB1 window. At least one PDCCH monitoring occasion of a type 1 PDCCH CSS set can be arranged within the RAR window. The starting point of the SIB1 window can be determined based on UL WUS resources, identical to or similar to the RAR window. For example, the SIB1 window can start from a subframe (or slot) shifted by C3 subframe(s) (or slot(s)) from a subframe (or slot) to which the UL WUS resource belongs. C3 can be a natural number. The time order between the SIB1 window and the RAR window can be defined. In the embodiment of FIG. 15, the SIB1 window may precede the RAR window in the time domain. For example, the SIB1 window may be positioned between the UL WUS resource and the RAR window. The SIB1 window and the RAR window may not overlap each other. In other words, the SIB1 window and the RAR window may be temporally separated. The time interval between the RAR window and the SIB1 window may be defined. Alternatively, the time interval between the RAR window and the SIB1 window may be set in the terminal. The subframes (or slots) forming the RAR window may be determined by the time interval. The time interval may mean C2 subframe(s), C2 slot(s), or C2 symbol(s). C2 may be a natural number. C2 may be defined as the minimum time gap between the time at which SIB1 (e.g., SIB1 PDSCH) is transmitted within the SIB1 window and the time at which RAR (e.g., RAR PDCCH) is transmitted within the RAR window.

[0217] Meanwhile, the time order between the SIB1 window and the RAR window may not be enforced. The time order between the SIB1 window and the RAR window may be implemented by the base station. In this case, the SIB1 window may be arranged in a period later than the RAR window. Alternatively, the SIB1 window and the RAR window may overlap in time. The starting point of the SIB1 window (e.g., the starting slot) may be determined based on any point in time (e.g., the first slot or the last slot) of the RAR window. The transmission order of SIB1 and Msg2 (e.g., the reception order of SIB1 PDCCH and Msg2 PDCCH) may not be defined in the technical specification. In this case, the configuration information required for Msg2 reception (e.g., carrier, DL bandwidth portion, numerology, CORESET, Type 1-PDCCH CSS set, PDSCH configuration, etc.) may be included in the UL WUS configuration information and transmitted to the terminal. The terminal can successfully receive Msg2 before receiving SIB1 based on the above information. The information included in the UL WUS configuration information can be identically included in the SIB1 of the NES cell (e.g., on-demand SIB1). The values ​​of the parameters included in the UL WUS configuration information and the values ​​of the parameters included in SIB1 for the same parameter can be identical. If the values ​​of the parameters included in the UL WUS configuration information and the values ​​of the parameters included in SIB1 for the same parameter do not match, the terminal can apply one of the parameter values ​​according to the priority rule. For example, the SIB1 configuration can have a higher priority than the UL WUS configuration. In this case, the terminal can perform the corresponding operation according to the parameter value of the SIB1 configuration.

[0218] Fig. 16 is a conceptual diagram illustrating a fourth embodiment of a four-step random access method based on UL WUS.

[0219] Referring to FIG. 16, the terminal may receive SIB1 and Msg2 after UL WUS transmission. Msg2 may be received within the RAR window, and a time window for SIB1 transmission may not be separately set. SIB1 may be transmitted at a time earlier than Msg2. For example, similarly or identically to the third embodiment, a minimum time gap between the time at which SIB1 (e.g., SIB1 PDSCH) is transmitted and the time at which RAR (e.g., RAR PDCCH) is transmitted may be defined (e.g., set). The minimum time gap may correspond to C2. Alternatively, a minimum time gap between the time at which SIB1 (e.g., SIB1 PDSCH) is transmitted and the start time of the RAR window may be defined (e.g., set). In the present disclosure, SIB1 may be transmitted at a time later than RAR. Alternatively, SIB1 may be transmitted simultaneously with RAR.

[0220] The terminal can basically monitor the SIB1 PDCCH in the search space set allocated after the UL WUS resource. In order to minimize the time required for the random access procedure of the terminal, it may be desirable for the cell to transmit the SIB1 at the earliest possible point after receiving the UL WUS. The slot (or symbol) in which the terminal monitors the SIB1 PDCCH after the UL WUS transmission may be fixed to the slot (or symbol) subsequent to D slot(s) (or symbol(s)) from the slot (or symbol) to which the UL WUS resource is mapped. The D value may be determined to reflect the minimum time required for the UL WUS reception processing and / or SIB1 transmission preprocessing of the cell. For example, the terminal may transmit the UL WUS in slot n and monitor the SIB1 PDCCH in slot (n+D). Each of n and D may be a natural number. For the above operation, the base station may necessarily set a PDCCH monitoring occasion of the search space set in slot (n+D) when UL WUS resources are set in slot n. Alternatively, without signaling the search space set, the terminal may find out the location of the search space set arranged in slot (n+D) by a predefined rule when UL WUS resources are set in slot n, and monitor the SIB1 PDCCH in the search space set.

[0221] In a modified method for (Method 200), SIB1 and Msg2 may be transmitted to the terminal in the same PDSCH. The PDSCH may be a SIB1 PDSCH and may be scheduled by a SIB1 PDCCH (e.g., a PDCCH having a CRC scrambled by SI-RNTI). Alternatively, the PDSCH may be a Msg2 PDSCH and may be scheduled by a Msg2 PDCCH (e.g., a PDCCH having a CRC scrambled by RA-RNTI). Alternatively, the PDSCH may be a PDSCH distinct from the SIB1 PDSCH and the Msg2 PDSCH. The PDSCH may still be scheduled by a DL fallback DCI (e.g., DCI format 1_0), and the DCI may be monitored in a CSS set. The above CSS set may be a type 0 / 1 PDCCH CSS set or a CSS set separately configured in the terminal. The terminal may monitor only one search space set to receive the PDSCH.

[0222] As a modified method for (Method 200), the terminal may expect to receive only SIB1 without Msg2 after UL WUS transmission. SIB1 may solely serve as a response message or a confirm message of the UL WUS, and the terminal may transmit Msg3 PUSCH to the cell after successfully receiving SIB1. SIB1 may include resource allocation and scheduling information, UL timing-related information, etc. required for Msg3 PUSCH transmission by the terminal. Conversely, the terminal may expect to receive Msg2 after UL WUS transmission, and may transmit Msg3 PUSCH to the cell without receiving SIB1. Information required for transmission of Msg3 PUSCH may be included in Msg2 and transmitted to the terminal. Alternatively, information required for transmission of Msg3 PUSCH may be transmitted to the terminal from a cell (e.g., an anchor cell) different from the cell (e.g., an NES cell).

[0223] According to the above-described method, the terminal can receive SIB1 before receiving Msg2, and configuration information required for receiving Msg2 (e.g., carrier, DL bandwidth part, numerology, CORESET, Type 1-PDCCH CSS set, PDSCH configuration, etc.) can be included in SIB1 and transmitted to the terminal before the terminal receives Msg2 PDCCH / PDSCH. The terminal can monitor the Msg2 PDCCH within the RAR window based on the information included in SIB1 without a separate operation of storing a DL signal in a buffer, and can receive the Msg2 PDSCH corresponding to the Msg2 PDCCH.

[0224] Alternatively, the search space set for transmitting the Msg2 PDCCH can be configured in the UE via the MIB (e.g., PBCH). In other words, the Type 0-PDCCH CSS set can be configured via the MIB, and the UE can monitor the Msg2 PDCCH (e.g., DCI having a CRC scrambled by the RA-RNTI) in the Type 0-PDCCH CSS set. The value of the RA-RNTI required for monitoring the Msg2 PDCCH can be predefined in the technical specification. Alternatively, the value of the RA-RNTI required for monitoring the Msg2 PDCCH can be included in the UL WUS configuration information and transmitted to the UE in advance. The Msg2 PDSCH can be scheduled in the initial DL bandwidth portion. The initial DL bandwidth portion can mean the bandwidth of CORESET0 configured via the MIB, and the number of RBs in the initial DL bandwidth portion can mean the number of RBs in CORESET0. According to the above-described method, the terminal can obtain the configuration information required for receiving Msg2 without relying on SIB1, and can successfully receive Msg2 before receiving on-demand SIB1. The above-described Msg2 receiving method can be applied temporarily. For example, the above-described Msg2 receiving method can be applied before the terminal receives SIB1 (e.g., on-demand SIB1), and after obtaining the SIB1 message, the terminal can receive Msg2 based on the configuration information included in SIB1. Alternatively, in the above-described case (e.g., when the UL WUS configuration information does not include configuration information for a separate search space set for monitoring Msg2 PDCCH, and the terminal monitors Msg2 PDCCH in a type 0-PDCCH CSS set), the terminal can expect that the configuration information for a separate search space set for monitoring Msg2 PDCCH is not included in SIB1 either.In other words, whether or not the configuration information of the search space set for the Msg2 PDCCH (e.g., the Type 1-PDCCH CSS set) is included can be commonly applied to the UL WUS configuration and SIB1. In the above case, the UE can still monitor the Msg2 PDCCH in the Type 0-PDCCH CSS set even after receiving SIB1 (e.g., the on-demand SIB1).

[0225] Figure 17 is a flowchart illustrating a first embodiment of a random access method based on a conventional two-step RACH procedure.

[0226] Referring to FIG. 17, a terminal may transmit a UL WUS to a cell (e.g., a base station) and then receive SIB1 from the cell. The terminal may receive a RAR, which is a response message to the UL WUS, from the cell. After receiving SIB1, the terminal may perform a two-step random access operation based on a legacy RACH procedure. For example, after receiving SIB1, the terminal may transmit a MsgA PRACH / PUSCH to the cell. In other words, the random access procedure of the terminal may be separated from the SIB1 trigger operation and the SIB1 reception operation. According to the above method, the UL WUS transmission and the MsgA PRACH transmission may be unnecessarily overlapped. Accordingly, the terminal may receive the RAR twice.

[0227] Fig. 18 is a flowchart illustrating a first embodiment of a two-step random access method based on UL WUS.

[0228] Referring to FIG. 18, a terminal may enter a random access procedure at the same time as requesting SIB1 transmission by transmitting an UL WUS to a cell (e.g., a base station). The UL WUS resource may include a first resource, and the first resource may be a PUSCH. Alternatively, the UL WUS may be transmitted together with the MsgA PUSCH in a UL WUS resource formed only by RO(s). The terminal may expect to receive a response message for the UL WUS and / or the MsgA PUSCH from the cell. The response message may include SIB1 and / or MsgB. The step of transmitting and receiving the response message may be regarded as the second step of a two-step RACH procedure. The terminal may receive SIB1 and / or MsgB and complete the two-step RACH procedure. According to the above method, the MsgA PRACH transmission procedure and / or the MsgB reception procedure may be omitted, and the above-described unnecessary duplication problem may be solved. The time required for the random access procedure can be shortened. The above-described embodiment may be referred to as (method 300).

[0229] Figure 19 is a flowchart illustrating a second embodiment of a two-step random access method based on UL WUS.

[0230] Referring to FIG. 19, the random access procedure may be a random access procedure according to a variation of (method 300). The terminal may transmit an UL WUS to the cell and receive SIB1 in response to the UL WUS. The UL WUS resource may be formed only by RO(s). After receiving SIB1, the terminal may transmit an MsgA PUSCH to the cell based on the configuration information included in SIB1, and may receive an MsgB in response to the MsgA PUSCH.

[0231] Methods according to embodiments of the 4-step RACH procedure may be applied identically or similarly to (method 300). For example, SIB1 and MsgB may be received in a RAR window or a window defined for receiving MsgB (hereinafter referred to as MsgB window). Alternatively, SIB1 may be received in the SIB1 window, and MsgB may be received in the RAR window (or MsgB window). Alternatively, MsgB may be received in the RAR window (or MsgB window), and a reception window for SIB1 may not be separately defined. In this case, SIB1 reception may precede MsgB reception, and a minimum time gap between SIB1 reception and MsgB reception may be defined by the above-described method. SIB1 reception may be received by one SIB1 PDCCH and one SIB1 PDSCH. Alternatively, reception of SIB1 may be received by multiple SIB1 PDCCHs and multiple SIB1 PDSCHs that are repeatedly transmitted.

[0232] In summary, the above-described method can be used to trigger SIB1 transmission or "SIB1 transmission and RACH procedure" by transmitting an UL WUS to a cell. In more detail, the RACH procedure can be used to trigger "SIB1 transmission and 4-step RACH procedure" or "SIB1 transmission and 2-step RACH procedure" by transmitting an UL WUS. Whether to perform a random access procedure after the UL WUS transmission can be determined by the terminal (e.g., an upper layer of the terminal). The terminal can transmit the UL WUS together with information about the purpose of transmitting the UL WUS (e.g., information about whether to perform a random access procedure for the cell) to the base station. The information can be conveyed to the base station explicitly or implicitly via the UL WUS. The information can be terminal assistance information.

[0233] Specifically, the UL WUS preamble for SIB1 transmission trigger (or camping) and the UL WUS preamble for random access procedure can be configured separately. For example, the UL WUS preamble for SIB1 transmission trigger (or camping) and the UL WUS preamble for random access procedure can be configured separately within each RO or each preamble group. The set of UL WUS preambles for SIB1 transmission trigger (or camping) can be referred to as a first preamble set. The set of UL WUS preambles for random access procedure can be referred to as a second preamble set. Both the first preamble set and the second preamble set can be configured by a UL WUS configuration. Alternatively, the first preamble set can be configured by a UL WUS configuration, and the second preamble set can be configured by a separate PRACH configuration. According to the above embodiment, the first preamble set can include only one preamble.

[0234] If a base station (e.g., an NES cell) receives a UL WUS preamble belonging to the first preamble set, the NES cell may transmit SIB1 and may not transmit Msg2 or MsgB. Alternatively, the base station (e.g., an NES cell) may transmit Msg2 or MsgB to the UE as an acknowledgement / response message for the UL WUS, but may not expect to receive Msg3 (e.g., Msg3 PUSCH) from the UE. In other words, a random access procedure may not be performed in the NES cell. On the other hand, if a base station (e.g., an NES cell) receives a UL WUS preamble belonging to the second preamble set, the NES cell may transmit SIB1 and may enter a random access procedure by transmitting Msg2 or MsgB. The terminal may transmit Msg3 corresponding to the received Msg2 or MsgB to the NES cell, and may receive Msg4 from the NES cell. The UL WUS transmission may be part of the random access procedure, and the UL WUS may be considered as Msg1. The response message corresponding to the UL WUS (e.g., RAR) may be part of the random access procedure, and the response message may be considered as Msg2 (or MsgB).

[0235] According to the above-described method, the UL WUS preamble transmitted by the terminal can be determined based on the purpose of requesting SIB1 transmission. The message composition of Msg2 or MsgB received by the terminal can be determined based on the purpose of requesting SIB1 transmission. For example, the message composition of Msg2 (hereinafter referred to as first Msg2) received when the terminal transmits a UL WUS preamble belonging to a first preamble set may be different from the message composition of Msg2 (hereinafter referred to as second Msg2) received when the terminal transmits a UL WUS preamble belonging to a second preamble set. For example, a specific message / parameter included in the second Msg2 may not be included in the first Msg2. Or, a specific message / parameter included in the first Msg2 may not be included in the second Msg2. In one embodiment, the second Msg2 may include information (e.g., RAR UL grant) required for transmission of Msg3 by the terminal. On the other hand, the first Msg2 may not include information (e.g., RAR UL grant) related to transmission of Msg3. Alternatively, the RAR UL grant included in the first Msg2 may have a different field / parameter configuration from the RAR UL grant included in the second Msg2. The second Msg2 may include a temporary C-RNTI, but the first Msg2 may not include a temporary C-RNTI. A timing advance (TA) required for UL transmission by the terminal may be included in the second Msg2 and may not be included in the first Msg2. The message sizes of the first Msg2 and the second Msg2 may be different from each other.

[0236] Certain messages / parameters may be commonly included in the first Msg2 and the second Msg2. For example, a random access preamble ID (RAPID) may be included in the first Msg2 and the second Msg2. If the RAPID matches the ID of the UL WUS preamble transmitted by the terminal, the terminal may consider that the base station has successfully received the UL WUS. The terminal may expect to receive SIB1 from the cell that transmitted the UL WUS and may not perform a UL WUS retransmission operation. Regardless of the message structure, the MAC subheader may be commonly included in the first Msg2 and the second Msg2.

[0237] The message compositions of Msg2 1 and Msg2 2 may be predefined in the technical specifications. Alternatively, the message compositions of some Msg2 (e.g., Msg2 1) may be included in the UL WUS configuration information and signaled to the terminal. The terminal may receive Msg2 based on the assumption that the Msg2 message composition corresponds to the UL WUS preamble transmitted by the terminal.

[0238] When the terminal receives the second Msg2, it can sequentially perform the transmission and reception operations of Msg3 and Msg4. When the terminal receives the first Msg2, it may not perform the transmission and reception operations of Msg3 and Msg4. In other words, when the received Msg2 includes at least an RAR UL grant, the terminal can perform the transmission operation of Msg3 corresponding to Msg2.

[0239] Alternatively, the message composition of Msg2 can be indicated by the MAC subheader included in Msg2. The terminal can determine the message composition of Msg2 based on the MAC subheader and receive Msg2 based on the message composition. According to the above method, the message composition of Msg2 can be determined by the base station. For example, the base station can select one of the first Msg2 and the second Msg2 regardless of the preamble group to which the received UL WUS preamble belongs, and transmit the selected Msg2 to the terminal. For example, even if the terminal requests to perform a random access procedure by transmitting a preamble belonging to the second preamble group, the base station can instruct the terminal not to perform the random access procedure by transmitting the first Msg2. In other words, the subsequent procedure according to the SIB1 request can be determined by the base station, not the terminal.

[0240] The UL WUS preamble for SIB1 transmission trigger (or camping), the UL WUS preamble for the 4-step RACH procedure, and the UL WUS preamble for the 2-step RACH procedure can be separately configured within each RO or each preamble group. The base station can receive the UL WUS preamble from the terminal and perform an operation corresponding to the UL WUS preamble.

[0241] According to the above-described method, the PRACH preamble can be reused as a UL WUS, and the UL WUS resources can be determined by the PRACH configuration. For example, at least some of the PRACH preambles allocated for a 4-step RACH procedure by the PRACH configuration can be configured as a first UL WUS preamble. At least some of the PRACH preambles allocated for a 2-step RACH procedure by the PRACH configuration can be configured as a second UL WUS preamble. Simultaneously or separately from the above embodiment, at least some of the PRACH preambles allocated for a non-contention-based RACH procedure by the PRACH configuration can be configured as a third UL WUS preamble. Alternatively, there may be a preamble that is not allocated for the PRACH within the RO or preamble group, and the preamble that is not allocated for the PRACH can be configured as a fourth UL WUS preamble.

[0242] Each RO or each preamble group may include at least a portion of the first UL WUS preamble to the fourth UL WUS preamble. The UE may inform the cell of the purpose of the UL WUS transmission by selectively transmitting at least a portion of the first UL WUS preamble to the cell. The UE may trigger both SIB1 transmission and a four-step RACH procedure to the cell by transmitting the first UL WUS preamble, and may trigger both SIB1 transmission and a two-step RACH procedure to the cell by transmitting the second UL WUS preamble. The UE may trigger only SIB1 transmission to the cell by transmitting the third UL WUS preamble or the fourth UL WUS preamble. In this case, the RACH procedure may not be triggered. The PRACH preamble allocated for non-contention-based RACH may not be used by the UE in RRC idle / inactive mode. Therefore, when the terminal wants to trigger only SIB1 transmission, it may be appropriate to transmit the third UL WUS preamble corresponding to the PRACH preamble. By the above-described method, the base station can confirm the trigger information (e.g., request) of the terminal corresponding to the UL WUS preamble received in the cell, and the SIB1 transmission and / or RACH procedure can be performed in the cell based on the confirmed trigger information.

[0243] In a different method from the above, information regarding the purpose of transmitting UL WUS (e.g., information regarding whether a random access procedure is performed for the cell) may be transmitted by being included in a first resource. For example, the first resource may be a PUSCH or an MsgA PUSCH. The information may have a size of several bits or several bytes. The information may be defined in the form of a UCI, a MAC CE, etc. The information may be polar encoded or LDPC (low density parity check) encoded. The information may be transmitted by being included in a PUSCH. Alternatively, the information may be transmitted by being piggybacked on a PUSCH.

[0244] [On-Demand SIB1 Transmission Method]

[0245] A cell receiving an UL WUS can transmit SIB1 to the UE based on several methods. First, SIB1 (e.g., SIB1 PDCCH) can be transmitted in a Type 0 PDCCH CSS set configured in the UE via the MIB. SIB1 can be transmitted periodically and semi-permanently until the base station decides to stop transmitting SIB1. In other words, the UE can periodically monitor SIB1 PDCCH in the Type 0 PDCCH CSS set after transmitting the UL WUS. Alternatively, the UE can monitor SIB1 PDCCH only for a few periods of the Type 0 PDCCH CSS set configured by the MIB, and may not monitor SIB1 PDCCH after the few periods. For example, the UE can monitor SIB1 PDCCH in P consecutive SSB period(s) or P consecutive SIB1 transmission period(s) starting from the same SSB period as the period in which the UL WUS is transmitted or from the period following the period. P can be a natural number. For example, P can be 1. The terminal can monitor the SIB1 PDCCH within the SSB period (or SIB1 period) in which the UL WUS is transmitted or within the next period of the SSB period (or SIB1 period). If the terminal fails to receive the SIB1 PDCCH and / or the SIB1 PDSCH in the P SSB period(s) or the P SIB1 period(s), the terminal can consider that the SIB1 corresponding to the SIB1 request is not transmitted in the cell. The above-described embodiment can be referred to as (method 400).

[0246] According to the above-described method, a delay of up to a time corresponding to the SIB1 monitoring cycle (e.g., several tens of milliseconds) may occur between the time the terminal transmits the UL WUS and the time it receives the SIB1. If the terminal wishes to camp on an NES cell, the delay time may be sufficiently tolerable. If the terminal transmits the UL WUS and attempts random access to the NES cell, a method for further reducing the delay time may be required to improve random access performance and delay time.

[0247] In order to reduce the above delay time, a method of arranging UL WUS resources immediately before the SIB1 monitoring interval may be considered. For example, the time resource of the UL WUS may be expressed as a slot offset from the SIB1 monitoring interval, and the slot offset (e.g., the time resource of the UL WUS) may be configured in the terminal. Specifically, the SIB1 monitoring interval may correspond to one or more half radio frame(s). The slot to which the UL WUS is mapped (e.g., the first slot) may be expressed as a slot that is ahead by a slot offset (e.g., X slot(s)) from the start slot of the first half radio frame. X may be a natural number. Alternatively, the slot to which the UL WUS is mapped (e.g., the first slot) may be expressed as a slot offset from the first slot to which a type 0-PDCCH CSS set is mapped within one period. Alternatively, the SSB monitoring interval may be used as a reference point instead of the SIB1 monitoring interval. For example, the slot to which a UL WUS is mapped (e.g., the first slot) can be expressed as a slot offset from the first slot to which a SSB is mapped within one cycle.

[0248] Alternatively, the terminal may receive configuration information of an additional search space set for monitoring the SIB1 PDCCH. The additional search space set may be determined based on a signaling procedure other than the MIB (e.g., SIBx, DCI) and / or the location of UL WUS transmission resources. The additional search space set may refer to additional PDCCH monitoring occasions of the Type 0 PDCCH CSS set. Alternatively, the additional search space set may refer to a CSS set distinct from the Type 0 PDCCH CSS set and PDCCH monitoring occasions of the CSS set. In embodiments of the UL WUS-based random access procedure, the resource for the terminal to monitor the SIB1 PDCCH may be the additional search space set. The additional search space set may appear periodically and repeatedly according to a predetermined period value. The terminal may periodically monitor the additional search space set. The period value may be set independently from a period value of an SSB, a period value of a legacy SIB1, etc. The above period value may have a different value from the period value of SSB, the period value of legacy SIB1, etc. Alternatively, the additional search space set may be configured aperiodically. For example, in order to support a 4-step RACH procedure of the terminal, the additional search space set for SIB1 reception may be monitored during “a time interval determined between the UL WUS transmission time of the terminal and the Msg2 reception time” or “a time interval determined between the UL WUS transmission time of the terminal and the Msg3 PUSCH transmission time.” The additional search space set may not be monitored during a time interval other than the above time interval.In other words, when the terminal monitors the Type 0-PDCCH CSS set in the above time interval, it may not monitor the conventional Type 0-PDCCH CSS set (e.g., the Type 0-PDCCH CSS set that is periodically set based on a period value such as SSB through MIB). According to the above embodiments, the time interval may be a SIB1 window or a RAR window. In the following, for convenience, the time interval may be collectively referred to as a SIB1 window. The above-described embodiment may be referred to as (method 410).

[0249] The above-described methods can be used together or alone. For example, SIB1 can be monitored in both the Type 0 PDCCH CSS set configured by the MIB and the additional search space set. Specifically, the terminal can monitor SIB1 in the SIB1 window after transmitting the UL WUS, and can periodically monitor SIB1 in the Type 0-PDCCH CSS set indicated by the MIB. Alternatively, the terminal can monitor only one of the Type 0 PDCCH CSS set configured by the MIB and the additional search space set based on a predetermined condition or an instruction (e.g., configuration) from the base station.

[0250] The SIB1 window can be set to the terminal by explicit signaling. For example, "the start time and / or end time of the SIB1 window" or "information about the start time and / or length of the SIB1 window" can be signaled to the terminal. The SIB1 window can be set in slot units, and the start time, end time, and / or length of the SIB1 window can correspond to slot(s). Alternatively, the SIB1 window can be set in subframe or ms (millisecond) units, and the start time, end time, and / or length of the SIB1 window can correspond to subframe(s) or time values ​​in ms units.

[0251] The SIB1 window can be determined implicitly. Alternatively, the SIB1 window can be determined by a combination of implicit and explicit methods. For example, the SIB1 window can start from a time point that is a predetermined time offset from a reference time point. The reference time point can mean a time point (e.g., a symbol, a slot) at which the UE transmits a UL WUS. The time offset can be defined as slot(s), symbol(s), or "a combination of slot(s) and symbol(s)." The time offset can be configured in the UE. For another example, the SIB1 window can start from a slot or symbol to which a specific CORESET (or PDCCH monitoring occasion) is mapped after the reference time point. The reference time point can mean a time point (e.g., a symbol, a slot) at which the UE transmits a UL WUS or a time point that is a predetermined time offset from the UL WUS transmission time point. The above specific CORESET (or PDCCH monitoring occasion) may mean a CORESET (or PDCCH monitoring occasion) for monitoring the additional search space set, a CORESET (or PDCCH monitoring occasion) for a type 0-PDCCH CSS set, etc. In the above method, the time point at which the terminal transmits the UL WUS may mean a time resource to which the RO to which the terminal transmitted the UL WUS preamble is mapped. Alternatively, the reference time point may be any one time point of the RAR window (e.g., the first slot, the last slot, the slot at which the terminal received Msg2), and the SIB1 window may be arranged in a section later by a time offset from any one time point of the RAR window. In the above method, the length of the SIB1 window may be determined as a separately defined value (e.g., a set value).

[0252] For multi-beam transmission, a plurality of SIB1 PDCCH monitoring occasions can be mapped to a SIB1 window. The plurality of SIB1 PDCCH monitoring occasions can be correlated with SSBs. The SSBs can be valid SSBs. The terminal can obtain information about valid SSBs included in the UL WUS configuration information in advance by the above-described method, map the plurality of SIB1 PDCCH monitoring occasions to valid SSBs, and monitor the SIB1 PDCCH monitoring occasion(s) corresponding to a specific SSB (e.g., valid SSB) based on the mapping. When the number of valid SSBs is M, the terminal can expect that at least M SIB1 PDCCH monitoring occasions corresponding to M valid SSBs will be mapped to the SIB1 window or the RAR window. When the number of SIB1 PDCCH monitoring occasions included in a window exceeds M, at least some SSBs may be mapped to multiple SIB1 PDCCH monitoring occasions within the window. M may be a natural number. The terminal may monitor only the SIB1 PDCCH monitoring occasion(s) associated with the SSB selected by the terminal among the SIB1 PDCCH monitoring occasions. Assuming that M SIB1 PDCCH monitoring occasions correspond to M valid SSBs, the SIB1 PDCCH need not be transmitted on all of the M SIB1 PDCCH monitoring occasions. The base station may infer a reception beam (e.g., an SSB beam) of the terminal requesting SIB1 based on the UL WUS received from the terminal, and may transmit the SIB1 PDCCH on the SIB1 PDCCH monitoring occasion corresponding to the reception beam. The base station may or may not transmit the SIB1 PDCCH on the remaining (M-1) SIB1 PDCCH monitoring occasions.

[0253] In order to provide DL coverage corresponding to UL WUS coverage, SIB1 PDSCH triggered by SIB1 request of UE may be repeatedly transmitted. The repeatedly transmitted SIB1 PDSCHs may be scheduled by SIB1 PDCCH(s) that are correlated with the same SSB and may be received by the same receive beam (e.g., QCL, QCL Type D, DL TCI, etc.). The repeatedly transmitted SIB1 PDSCHs may include the same TB (e.g., the same DL-SCH), and consequently, the repeatedly transmitted SIB1 PDSCHs may include the same SIB1 message. The UE may receive at least some (e.g., one or more SIB1 PDSCH(s)) of the repeatedly transmitted SIB1 PDSCHs, and may soft combine multiple SIB1 PDSCH(s) to improve reception performance.

[0254] Repeatedly transmitted SIB1 PDSCHs may be scheduled by different DCIs. For example, multiple SIB1 PDCCHs may be transmitted within a SIB1 window, and one SIB1 PDCCH may schedule one SIB1 PDSCH that constitutes a repeated transmission. Only one SIB1 PDCCH may be received in each CORESET (e.g., each PDCCH monitoring occasion), and multiple SIB1 PDCCHs may be received in different CORESETs (e.g., different PDCCH monitoring occasions). Each SIB1 PDCCH may have unique scheduling information for SIB1 PDSCH scheduling. In other words, the payloads of the multiple DCIs corresponding to the multiple SIB1 PDCCHs do not necessarily need to be identical. Multiple SIB1 PDSCHs scheduled by the multiple SIB1 PDCCHs may be mapped to different slots. The maximum number of repeated transmissions K of the SIB1 PDSCH may be defined in the technical specification. K can be a natural number. The terminal may not expect to receive the SIB1 PDSCH for the same SIB1 more than K times within one window or one SIB1 transmission period. On the other hand, the number L of SIB1 PDCCH monitoring occasions arranged within the SIB1 window for repeated transmission of the SIB1 PDSCH can be signaled from the base station to the terminal. For example, the value L can be included in the UL WUS configuration information. L can be a natural number. The SIB1 PDCCH monitoring occasions can be repeated L times for each SSB (e.g., valid SSB). In this case, the number of SIB1 PDCCH monitoring occasions arranged within the SIB1 window can be M×L in total. The terminal can monitor L SIB1 PDCCH monitoring occasions corresponding to the SSB selected by the terminal from among the M×L SIB1 PDCCH monitoring occasions in total.SIB1 PDCCH monitoring occasions can be TDM'd. In other words, SIB1 PDCCH monitoring occasions can be mapped to different time resources.

[0255] Alternatively, the L-repeated SIB1 PDCCH monitoring occasions can be mapped to L SIB1 windows, respectively, and one SIB1 PDCCH monitoring occasion can be monitored within one SIB1 window. Considering multi-beam operation, the terminal can monitor M SIB1 PDCCH monitoring occasions associated with different SSBs within each SIB1 window.

[0256] According to the above-described method, as the number of repeated transmissions of SIB1 PDSCH increases, control signaling overhead may also increase. As a method for solving the above problem, repeatedly transmitted SIB1 PDSCHs may be scheduled by one DCI. The one DCI may be transmitted by the above-described method within the SIB1 window. The number of SIB1 PDSCHs constituting the repeated transmission may be predefined in the technical specification. Alternatively, the number of repeated transmissions of SIB1 PDSCH may be included in the UL WUS configuration information and signaled to the terminal. Alternatively, the number of repeated transmissions of SIB1 PDSCH may be signaled to the terminal together with the UL WUS configuration information. In a more flexible method, the number of repeated transmissions of SIB1 PDSCH may be included in the DCI and dynamically signaled to the terminal. SIB1 PDSCHs may be mapped to consecutive slots, and SIB1 PDSCHs may be mapped to the same time-frequency resource in each slot. Some of the above SIB1 PDSCHs (e.g., SIB1 PDSCHs overlapping with UL symbols) may be dropped.

[0257] The configuration information regarding the SIB1 window may be included in the UL WUS configuration information and signaled to the terminal. Alternatively, the configuration information regarding the SIB1 window may be signaled to the terminal together with the UL WUS configuration information. Based on the configuration information, the terminal may determine a search space set(s) for monitoring the SIB1 PDCCH, receive the SIB1 PDCCH in the search space set(s), and receive the SIB1 PDSCH scheduled by the SIB1 PDCCH. Alternatively, the configuration information regarding the SIB1 window may be included in a DL signal (e.g., Msg2) received by the terminal after transmitting the UL WUS and transmitted to the terminal. Alternatively, the SIB1 window may be determined by a predefined rule without a separate signaling procedure.

[0258] Similar to the above-described embodiment, the UL WUS can be retransmitted. For example, the terminal can perform a blind detection operation for SIB1 after transmitting the UL WUS, and can retransmit the UL WUS if reception of SIB1 fails. In other words, SIB1 can be regarded as an acknowledgment message (e.g., a response message) for the UL WUS. The SIB1 blind detection operation can be performed for a predetermined time interval (e.g., a time window), and the time interval can be determined based on the resource location of the UL WUS transmitted by the terminal.

[0259] Meanwhile, according to (method 400), it may take a long time for the terminal to receive SIB1 after transmitting UL WUS. In this case, the NES cell may notify the terminal that it has successfully received the UL WUS by transmitting a DL signal other than SIB1, and the DL signal may be regarded as a confirmation message (e.g., a response message) for the UL WUS. For example, the DL signal may be Msg2 or MsgB. The terminal may monitor the DL signal (e.g., Msg2 or MsgB) for a certain time period (e.g., RAR window, Msg2 window), and may retransmit the UL WUS if reception or detection of the DL signal fails. The DL signal may be transmitted at a time earlier than the earliest SIB1 monitoring time of the terminal, and the UL WUS retransmission may be performed more quickly.

[0260] If the terminal successfully receives the DL signal but fails to receive SIB1, the terminal may regard the situation as an error operation of the base station. If the terminal fails to receive SIB1 after attempting to receive SIB1 for a certain period of time, the terminal may re-trigger SIB1 transmission by retransmitting UL WUS. The certain period of time may be predefined in the technical specification. For example, the certain period of time may be determined by a timer. The terminal may start the timer from the time of transmitting the UL WUS or from the time of receiving the DL signal, and if the terminal does not receive SIB1 until the timer expires, the terminal may retransmit the UL WUS after the timer expires.

[0261] Both the DL signal and SIB1 can be regarded as confirmation messages for the UL WUS. If either the DL signal (e.g., Msg2, MsgB) or SIB1 is not successfully received, the terminal can consider the UL WUS transmission as failed and retransmit the UL WUS. If either the DL signal (e.g., Msg2, MsgB) or SIB1 is successfully received, the terminal can consider the UL WUS transmission as successful and may not retransmit the UL WUS. In this case, the terminal can receive SIB1 regardless of whether the DL signal (e.g., Msg2, MsgB) is received. For example, the terminal may support both an operation of monitoring SIB1 PDCCH after receiving Msg2 and an operation of monitoring SIB1 PDCCH without receiving Msg2 (or an operation of receiving Msg2 after receiving SIB1).

[0262] UL WUS resources may be periodically configured for retransmission of UL WUS. Initial transmission and retransmission (or first retransmission and second retransmission) of UL WUS may be transmitted in different UL WUS periods. Alternatively, initial transmission and retransmission (or first retransmission and second retransmission) of UL WUS may be transmitted on different resources (e.g., UL WUS occasions) in the same UL WUS period. UL WUS occasions for different transmissions / retransmissions may be arranged such that there is a sufficiently long time interval between the UL WUS occasions to enable transmission of the DL signal. Alternatively, UL WUS resources (e.g., UL WUS occasions) can be configured without any constraints on the period value, and the terminal can retransmit the UL WUS in "the earliest UL WUS resource appearing after the interval in which the UL WUS confirmation message is received" or "the earliest UL WUS resource appearing after a predetermined time offset from the interval in which the UL WUS confirmation message is received." The interval in which the UL WUS confirmation message is received may include the Msg2 window, the MsgB window, and / or the SIB1 window.

[0263] [RRC connection mode operation]

[0264] After the terminal successfully completes the above-described UL WUS-based random access operation, the mode (e.g., operation mode) of the terminal may be switched to the RRC connected mode. In the RRC connected mode, the terminal may still transmit a preamble in the UL WUS resource. If the terminal does not receive SIB1 from the connected serving cell, the terminal may request transmission of SIB1 by transmitting the UL WUS. The terminal may transmit the preamble in the UL WUS resource (or the PRACH resource corresponding to the UL WUS resource) and trigger a contention-free based RACH procedure on the serving cell. In other words, the terminal may receive a PDCCH order from the serving cell, select one of the contention-free based RACH preambles allocated to the UL WUS RO (or the RACH RO corresponding to the UL WUS WO), and transmit the selected contention-free based RACH preamble to the serving cell. In other words, UL WUS resources and UL WUS transmission procedures may still be valid even in RRC connected mode. At this time, no other UL transmissions may be performed on the UL WUS resources. The UE may not expect overlap between the UL WUS resources and other semi-statically configured UL resources. The UL transmission may refer to UL transmissions other than the PRACH or random access preamble (e.g., PUCCH, PUSCH, SRS, etc.).

[0265] Meanwhile, the UL bandwidth portion of the terminal may be switched. Even if the UL WUS resource is allocated within the initial UL bandwidth portion, the UL WUS resource may not be completely included in the currently activated UL bandwidth portion due to bandwidth portion switching. Simultaneously or separately from the above embodiment, the UL WUS resource may overlap with a DL symbol. In this case, the UL WUS resource may be considered invalid. The terminal may obtain a new UL WUS resource configuration included in the activated UL bandwidth portion from the base station (or from the serving cell) and transmit a UL WUS using the new UL WUS resource. In other words, the UL WUS resource configuration may be updated. For example, the UL WUS resource may be configured for each UL bandwidth portion. When the UL WUS configuration is updated, the base station may transmit information to the terminal notifying that the UL WUS configuration has been updated. The information may be signaled to the terminal by being included in a paging message or paging DCI. The above information can be received by a terminal in RRC idle / inactive mode and / or a terminal in RRC connected mode.

[0266] Alternatively, the UE may not use UL WUS resources in RRC connected mode. The UE may ignore the configuration of UL WUS resources and perform other UL transmissions on the UL WUS resources. For example, PUSCH may be mapped and transmitted in a resource region that includes resources (e.g., REs) to which UL WUS is mapped. The unused UL WUS resources may refer to the time-frequency resource region to which UL WUS is mapped. Alternatively, the unused UL WUS resources may refer to a set of UL WUS preambles.

[0267] Similar to the above-described embodiment, on-demand SIB1 transmission may be performed in the form of burst transmission. In burst transmission, a predefined number of SIB1 bursts (e.g., a preset number) may be transmitted at once, and SIB1 may not be transmitted thereafter. SIB1 transmission may be activated and deactivated. SIB1 transmission in a cell may be activated by a UL WUS transmission of a terminal, and SIB1 may be transmitted periodically in a configured SIB1 resource (e.g., a type 0 PDCCH CSS set or the additional search space set). At this time, the base station may instruct other terminals connected to the cell (e.g., terminals in RRC connected mode) to receive the SIB1. SIB1 transmission in the cell may be deactivated, and SIB1 transmission in the resource may be stopped. At this time, the base station may notify the terminal through a signaling message that SIB1 transmission is disabled in the cell, that SIB1 transmission will be disabled in the cell, that SIB1 is not transmitted in the cell, or that SIB1 will not be transmitted in the cell. The signaling message (e.g., indication information) may be generated by a higher layer. For example, the indication information may be defined as a MAC CE or RRC message, and the indication information may be included in a PDSCH and transmitted to the terminal. As another example, the indication information may be dynamically signaled to the terminal by DCI. According to an embodiment, the DCI may be a paging DCI. The paging message may include new information required for on-demand SIB1 reception (e.g., information indicating an activation or deactivation status of SIB1). Alternatively, the terminal may receive information indicating that SIB1, UL WUS configuration, etc. have been updated by the paging message, and may receive on-demand SIB1 based on the received information.The terminal can perform a PDCCH monitoring operation in the SIB1 monitoring resource (e.g., SIB1 window) within the section in which the SIB1 monitoring resource is activated (e.g., the section in which the SIB1 PDCCH is transmitted). If the SIB1 monitoring resource is deactivated, the SIB1 monitoring resource can be used for other DL transmission. For example, the PDSCH can be mapped to a resource region including the SIB1 monitoring resource (e.g., the type 0 PDCCH CSS set or the additional search space set) and transmitted to the terminal.

[0268] The operations of the method according to the embodiments of the present disclosure can be implemented as a computer-readable program or code on a computer-readable recording medium. A computer-readable recording medium includes any type of recording device that stores information readable by a computer system. Furthermore, a computer-readable recording medium can be distributed across network-connected computer systems, allowing the computer-readable program or code to be stored and executed in a distributed manner.

[0269] Additionally, the computer-readable recording medium may include hardware devices specifically configured to store and execute program instructions, such as ROM, RAM, flash memory, etc. The program instructions may include not only machine language codes produced by a compiler, but also high-level language codes that can be executed by a computer using an interpreter, etc.

[0270] While some aspects of the present disclosure have been described in the context of a device, they may also represent a description of a corresponding method, wherein a block or device corresponds to a method step or a feature of a method step. Similarly, aspects described in the context of a method may also be described as a corresponding block or item or a feature of a corresponding device. Some or all of the method steps may be performed by (or using) a hardware device, such as, for example, a microprocessor, a programmable computer, or an electronic circuit. In some embodiments, at least one or more of the most significant method steps may be performed by such a device.

[0271] In embodiments, a programmable logic device (e.g., a field-programmable gate array) may be used to perform some or all of the functions of the methods described herein. In embodiments, the field-programmable gate array may operate in conjunction with a microprocessor to perform one of the methods described herein. In general, the methods are preferably performed by some hardware device.

[0272] Although the present disclosure has been described with reference to preferred embodiments thereof, it will be understood by those skilled in the art that various modifications and changes may be made to the present disclosure without departing from the spirit and scope of the present disclosure as set forth in the claims below.

Claims

1. As a terminal method, A step of receiving a first signaling message from a first cell; A step of receiving a second signaling message from a second cell; A step of performing a judgment procedure on whether to transmit a WUS (wake up signal) to the second cell based on the first signaling message and the second signaling message; A step of transmitting the WUS to the second cell from uplink resources based on the result of the above judgment procedure; A step of receiving a response message for the WUS from the second cell; and A step of receiving first system information of the second cell from the second cell, The above uplink resource is set based on the first signaling message, and the first system information includes at least SIB1 (system information block 1). Terminal method.

2. In claim 1, The first signaling message is included in the second system information of the second cell received from the first cell. Terminal method.

3. In claim 1, The second signaling message is a payload included in a master information block (MIB) received from the second cell or included in a physical broadcast channel (PBCH) received from the second cell. Terminal method.

4. In claim 1, The second signaling message includes a codepoint of a field indicating the number of subcarriers between an RB (resource block) occupied by an SSB (synchronization signal block) received from the second cell and an RB boundary of the second cell. Terminal method.

5. In claim 1, The above judgment procedure includes a procedure for judging whether the second cell is transmitting the first system information. Terminal method.

6. In claim 1, The above first system information is included in a PDSCH (physical downlink shared channel), and the terminal monitors a PDCCH (physical downlink control channel) that schedules the PDSCH in a search space set. Terminal method.

7. In claim 6, The configuration information of the above search space set is included in the MIB of the second cell together with the second signaling message, and the MIB is transmitted from the second cell to the terminal. Terminal method.

8. In claim 6, The configuration information of the above search space set is included in the second system information of the second cell together with the first signaling message, and the second system information is transmitted from the first cell to the terminal. Terminal method.

9. In claim 1, The first system information is received within a time window, and the time window is determined based on configuration information included in the second system information of the second cell including the first signaling message. Terminal method.

10. In claim 1, The terminal camps on the second cell based on the first system information regardless of the indication information of the access blocking field included in the MIB of the second cell. Terminal method.

11. As a method of base station, A step of transmitting a first signaling message to a terminal from a first cell of the base station; A step of transmitting a second signaling message to the terminal from the second cell of the base station; A step of receiving a WUS (wake up signal) from the terminal in the uplink resource of the second cell; A step of transmitting a response message for the WUS to the terminal in the second cell; and A step of transmitting first system information of the second cell to the terminal in the second cell, The above uplink resource is set based on the first signaling message, and the first system information includes at least SIB1 (system information block 1). Base station method.

12. In claim 11, The first signaling message is included in the second system information of the second cell transmitted from the first cell. Base station method.

13. In claim 11, The second signaling message is a payload included in a master information block (MIB) transmitted from the second cell or included in a physical broadcast channel (PBCH) transmitted from the second cell. Base station method.

14. In claim 11, The second signaling message includes a codepoint of a field indicating the number of subcarriers between an RB (resource block) occupied by an SSB (synchronization signal block) transmitted from the second cell and an RB boundary of the second cell. Base station method.

15. In claim 11, The above first system information is included in a PDSCH (physical downlink shared channel), and a PDCCH (physical downlink control channel) that schedules the PDSCH is transmitted in a search space set. Base station method.

16. In claim 15, The configuration information of the above search space set is included in the MIB of the second cell together with the second signaling message, and the MIB is transmitted from the second cell to the terminal. Base station method.

17. In claim 15, The configuration information of the above search space set is included in the second system information of the second cell together with the first signaling message, and the second system information is transmitted from the first cell to the terminal. Base station method.

18. In claim 11, The first system information is transmitted within a time window, the time window being determined based on configuration information included in the second system information of the second cell including the first signaling message. Base station method.

19. As a terminal, Contains at least one processor, At least one processor of the terminal, Receive a first signaling message from a first cell; Receive a second signaling message from a second cell; Performing a judgment procedure on whether to transmit a WUS (wake up signal) to the second cell based on the first signaling message and the second signaling message; Based on the result of the above judgment procedure, the WUS is transmitted to the second cell in the uplink resource; Receive a response message for the WUS from the second cell; and Causes the second cell to receive first system information of the second cell from the second cell, The above uplink resource is set based on the first signaling message, and the first system information includes at least SIB1 (system information block 1). Terminal.

20. In claim 19, The first signaling message is included in the second system information of the second cell received from the first cell. Terminal.

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