Method and apparatus for transmitting and receiving control channel

Abstract

A method according to an embodiment of the present specification comprises the steps of: receiving an SS / PBCH block; and receiving a PDCCH on the basis of a CORESET. The CORESET is acquired through interleaved mapping on the basis that the frequency domain size of the CORESET determined on the basis of a configuration related to the CORESET is related to a channel bandwidth that is less than 5 MHz. A shift value related to the interleaved mapping is determined on the basis of a defined shift value.

Description

Method and device for transmitting and receiving control channels

[0001] The present specification relates to a method and device for transmitting and receiving a control channel.

[0002] Mobile communication systems were developed to provide voice services while ensuring user activity. However, they have expanded beyond voice to include data services. Currently, explosive growth in traffic is leading to resource shortages and users are demanding faster services, necessitating a more advanced mobile communication system.

[0003] Next-generation mobile communication systems must support explosive data traffic growth, dramatically increasing data rates per user, a vastly increased number of connected devices, ultra-low end-to-end latency, and high energy efficiency. To achieve these goals, various technologies are being studied, including dual connectivity, massive multiple input multiple output (MIMO), in-band full duplex, non-orthogonal multiple access (NOMA), super wideband support, and device networking.

[0004] To efficiently support diverse use cases in 5G from a cost / complexity perspective, newly introduced terminal types may have reduced maximum bandwidth. For example, the maximum bandwidth may be reduced to 3MHz.

[0005] If the maximum bandwidth is reduced (e.g., to 3MHz), puncturing may be applied to the Control Resource SET (CORESET) to accommodate the reduced bandwidth.

[0006] Interleaved mapping is applied to CORESET #0. According to the existing operation, the mapping used is fixed to the cell ID. Therefore, as described above, when CORESET is acquired based on puncturing, a problem occurs in which the number of CCEs (Control Channel Elements) through which the PDCCH is transmitted changes.

[0007] The purpose of this specification is to propose a method to solve the above-mentioned problems.

[0008] The technical problems to be achieved in this specification are not limited to the technical problems mentioned above, and other technical problems not mentioned can be clearly understood by a person having ordinary skill in the technical field to which this specification pertains from the description below.

[0009] A method performed by a terminal according to one embodiment of the present disclosure includes the steps of receiving a Synchronization Signal / Physical Broadcast Channel (SS / PBCH) block and receiving a Physical Downlink Control Channel (PDCCH) based on a Control Resource Set (COntrol REsource SET, CORESET).

[0010] Based on the frequency domain size of the CORESET determined based on the settings related to the CORESET and related to a channel bandwidth of less than 5 MHz, the CORESET is obtained based on interleaved mapping.

[0011] The shift value associated with the above interleaved mapping is characterized in that it is determined based on a defined value.

[0012] The above defined values ​​can be set based on broadcast signaling.

[0013] Based on the above broadcast signaling, the settings related to the CORESET may be indicated. The settings related to the CORESET may be one of the settings defined in the table.

[0014] Each of the above settings may include i) the above defined value, ii) the number of Resource Blocks (RBs) related to the frequency domain size, iii) the number of symbols, and iv) an offset.

[0015] The above defined value can be determined based on puncturing associated with the CORESET.

[0016] The RBs (Resource Blocks, RBs) forming the above CORESET can be obtained by puncturing one or more of the RBs based on the frequency domain size.

[0017] The above defined value may be a value based on some of the obtained RBs.

[0018] The values ​​defined above may be values ​​that change based on time-varying units.

[0019] The initial value of the above defined value may be i) a value set based on broadcast signaling or ii) a value determined based on puncturing associated with the CORESET.

[0020] The above time-varying unit may be based on i) at least one slot or ii) a periodicity associated with a search space.

[0021] The above shift value can be determined as i) the above defined value or ii) a value obtained by adding the above defined value to the cell ID.

[0022] A terminal according to another embodiment of the present disclosure includes one or more transceivers, one or more processors, and one or more memories connected to the one or more processors and storing instructions.

[0023] The instructions are characterized in that, based on being executed by the one or more processors, the one or more processors are set to perform all steps of any one of the methods.

[0024] A device according to another embodiment of the present disclosure comprises one or more memories and one or more processors functionally connected to the one or more memories. The one or more memories are characterized in that they store instructions that, based on execution by the one or more processors, cause the one or more processors to perform all steps of any one of the above methods.

[0025] In another embodiment of the present disclosure, one or more non-transitory computer-readable media store instructions, the instructions being executable by one or more processors, characterized in that they cause the one or more processors to perform all steps of any one of the methods.

[0026] A method performed by a base station according to another embodiment of the present disclosure includes the steps of transmitting a Synchronization Signal / Physical Broadcast Channel (SS / PBCH) block and transmitting a Physical Downlink Control Channel (PDCCH) based on a Control Resource Set (COntrol REsource SET, CORESET).

[0027] Based on the frequency domain size of the CORESET determined based on the settings related to the CORESET and related to a channel bandwidth of less than 5 MHz, the CORESET is obtained based on interleaved mapping.

[0028] The shift value associated with the above interleaved mapping is characterized in that it is determined based on a defined value.

[0029] A base station according to another embodiment of the present disclosure includes one or more transceivers, one or more processors, and one or more memories coupled to the one or more processors and storing instructions.

[0030] The instructions are characterized in that they are executed by the one or more processors, and the one or more processors are set to perform all steps of the method.

[0031] According to the embodiments of the present specification, interleaved mapping applied to CORESET #0 is performed based on defined values. Accordingly, variability in cell-specific PDCCH transmission and reception performance can be minimized as puncturing is applied to CORESET in a narrow band.

[0032] Additionally, it can contribute to expanding the use cases of NR systems by resolving issues that may arise when supporting narrowband terminal / spectrum scenarios.

[0033] The effects that can be obtained from this specification are not limited to the effects mentioned above, and other effects that are not mentioned can be clearly understood by a person having ordinary skill in the technical field to which this specification belongs from the description below.

[0034] Figure 1 shows an example of a frame structure in an NR system.

[0035] Figure 2 shows an example of a resource grid in NR.

[0036] Figure 3 illustrates physical channels and general signal transmission used in a 3GPP system.

[0037] FIG. 4 is a drawing illustrating an SSB structure to which the method proposed in this specification can be applied.

[0038] Figure 5 illustrates the transmission of a synchronization signal block (SSB) to which the method proposed in this specification can be applied.

[0039] FIG. 6 is a flowchart illustrating DL signal / channel reception in an initial connection process to which a method according to an embodiment of the present specification can be applied.

[0040] FIG. 7 illustrates the time-frequency structure of SSB according to one embodiment of the present specification.

[0041] FIG. 8 illustrates a frequency resource region for PBCH transmission and reception according to one embodiment of the present specification.

[0042] FIG. 9 illustrates a frequency resource region for PBCH transmission and reception according to another embodiment of the present specification.

[0043] Figure 10 is a diagram illustrating a frequency domain related to PDCCH transmission and reception.

[0044] Figure 11 is a drawing illustrating Point A according to the conventional method.

[0045] Fig. 12 is a drawing illustrating Point A according to an embodiment of the present specification.

[0046] FIG. 13 is a drawing illustrating CORESET#0 based on an embodiment of the present specification.

[0047] FIG. 14 is a flowchart illustrating a method performed by a terminal according to one embodiment of the present specification.

[0048] FIG. 15 is a flowchart illustrating a method performed by a base station according to another embodiment of the present specification.

[0049] FIG. 16 is a drawing showing the configuration of the first device and the second device according to an embodiment of the present specification.

[0050] Hereinafter, downlink (DL) refers to communication from a base station to a terminal, and uplink (UL) refers to communication from a terminal to a base station. In downlink, a transmitter may be part of a base station, and a receiver may be part of a terminal. In uplink, a transmitter may be part of a terminal, and a receiver may be part of a base station. A base station may be expressed as a first communication device, and a terminal may be expressed as a second communication device. A base station (BS) may be replaced by terms such as a fixed station, Node B, eNB (evolved-NodeB), gNB (Next Generation NodeB), BTS (base transceiver system), access point (AP: Access Point), network (5G network), AI system, RSU (road side unit), vehicle, robot, drone (Unmanned Aerial Vehicle, UAV), AR (Augmented Reality) device, VR (Virtual Reality) device, etc. In addition, the terminal may be fixed or mobile, and may be replaced with terms such as UE (User Equipment), MS (Mobile Station), UT (user terminal), MSS (Mobile Subscriber Station), SS (Subscriber Station), AMS (Advanced Mobile Station), WT (Wireless terminal), MTC (Machine-Type Communication) device, M2M (Machine-to-Machine) device, D2D (Device-to-Device) device, vehicle, robot, AI module, drone (Unmanned Aerial Vehicle, UAV), AR (Augmented Reality) device, VR (Virtual Reality) device, etc.

[0051] The following technologies can be used in various wireless access systems, such as CDMA, FDMA, TDMA, OFDMA, and SC-FDMA. CDMA can be implemented using wireless technologies such as UTRA (Universal Terrestrial Radio Access) or CDMA2000. TDMA can be implemented using wireless technologies such as GSM (Global System for Mobile communications) / GPRS (General Packet Radio Service) / EDGE (Enhanced Data Rates for GSM Evolution). OFDMA can be implemented using wireless technologies such as IEEE 802.11 (Wi-Fi), IEEE 802.16 (WiMAX), IEEE 802-20, and E-UTRA (Evolved UTRA). UTRA is a part of UMTS (Universal Mobile Telecommunications System). 3GPP (3rd Generation Partnership Project) LTE (Long Term Evolution) is a part of E-UMTS (Evolved UMTS) that uses E-UTRA, and LTE-A (Advanced) / LTE-A pro is an evolved version of 3GPP LTE. 3GPP NR (New Radio or New Radio Access Technology) is an evolved version of 3GPP LTE / LTE-A / LTE-A pro.

[0052] For clarity, the description is based on the 3GPP communication system (e.g., LTE-A, NR), but the technical idea of ​​this specification is not limited thereto. LTE refers to technology after 3GPP TS 36.xxx Release 8. Specifically, LTE technology after 3GPP TS 36.xxx Release 10 is referred to as LTE-A, and LTE technology after 3GPP TS 36.xxx Release 13 is referred to as LTE-A pro. 3GPP NR refers to technology after TS 38.xxx Release 15. LTE / NR may be referred to as a 3GPP system. "xxx" refers to a standard document detail number. LTE / NR may be collectively referred to as a 3GPP system.

[0053] For background information, terminology, abbreviations, etc. used in the description of this specification, reference may be made to standard documents published prior to this specification. For example, reference may be made to the following documents:

[0054] 3GPP NR

[0055] - 3GPP TS 38.211: Physical channels and modulation

[0056] - 3GPP TS 38.212: Multiplexing and channel coding

[0057] - 3GPP TS 38.213: Physical layer procedures for control

[0058] - 3GPP TS 38.214: Physical layer procedures for data

[0059] - 3GPP TS 38.215: Physical layer measurements

[0060] - 3GPP TS 38.300: NR and NG-RAN Overall Description

[0061] - 3GPP TS 38.304: User Equipment (UE) procedures in idle mode and in RRC inactive state

[0062] - 3GPP TS 38.321: Medium Access Control (MAC) protocol

[0063] - 3GPP TS 38.322: Radio Link Control (RLC) protocol

[0064] - 3GPP TS 38.323: Packet Data Convergence Protocol (PDCP)

[0065] - 3GPP TS 38.331: Radio Resource Control (RRC) protocol

[0066] - 3GPP TS 37.324: Service Data Adaptation Protocol (SDAP)

[0067] - 3GPP TS 37.340: Multi-connectivity; Overall description

[0068] - 3GPP TS 23.287: Application layer support for V2X services; Functional architecture and information flows

[0069] - 3GPP TS 23.501: System Architecture for the 5G System

[0070] - 3GPP TS 23.502: Procedures for the 5G System

[0071] - 3GPP TS 23.503: Policy and Charging Control Framework for the 5G System; Stage 2

[0072] - 3GPP TS 24.501: Non-Access-Stratum (NAS) protocol for 5G System (5GS); Stage 3

[0073] - 3GPP TS 24.502: Access to the 3GPP 5G Core Network (5GCN) via non-3GPP access networks

[0074] - 3GPP TS 24.526: User Equipment (UE) policies for 5G System (5GS); Stage 3

[0075] As more and more communication devices demand greater communication capacity, the need for improved mobile broadband communication compared to existing radio access technology is emerging. Furthermore, massive MTC (Machine Type Communications), which connects multiple devices and objects to provide various services anytime, anywhere, is also a key issue to be considered in next-generation communication. Furthermore, communication system design that considers reliability- and latency-sensitive services / terminals is being discussed. Accordingly, the introduction of next-generation radio access technologies such as eMBB (enhanced mobile broadband communication), MMTC (massive MTC), and URLLC (Ultra-Reliable and Low Latency Communication) is being discussed, and for convenience, these technologies are referred to as NR in this specification. NR is an expression that represents an example of 5G radio access technology (RAT).

[0076] A new RAT system, including NR, uses OFDM or a similar transmission scheme. The new RAT system may follow OFDM parameters different from those of LTE. Alternatively, the new RAT system may follow the existing LTE / LTE-A numerology but have a larger system bandwidth (e.g., 100 MHz). Alternatively, a single cell may support multiple numerologies. That is, terminals operating under different numerologies can coexist within a single cell.

[0077] A numerology corresponds to a single subcarrier spacing in the frequency domain. Different numerologies can be defined by scaling the reference subcarrier spacing by an integer N.

[0078] NR (New Rat) Numerology and Frame Structure

[0079] In NR systems, multiple numerologies can be supported. Here, the numerologies can be defined by subcarrier spacing and CP (Cyclic Prefix) overhead. In this case, multiple subcarrier spacings are defined by the basic subcarrier spacing as an integer N (or, ) can be derived by scaling. Furthermore, even if it is assumed that very low subcarrier spacing is not used at very high carrier frequencies, the numerology used can be selected independently of the frequency band.

[0080] Additionally, the NR system can support various frame structures according to multiple numerologies.

[0081] Below, we examine the OFDM (Orthogonal Frequency Division Multiplexing) numerology and frame structure that can be considered in NR systems.

[0082] The multiple OFDM numerologies supported in the NR system can be defined as shown in Table 1. μ and cyclic prefix for the bandwidth part are obtained from the RRC parameters provided by the BS.

[0083]

[0084] NR supports multiple numerologies (or subcarrier spacings (SCS)) to support various 5G services. For example, an SCS of 15 kHz supports wide areas in traditional cellular bands; an SCS of 30 kHz / 60 kHz supports dense urban areas, lower latency, and wider carrier bandwidth; and an SCS of 60 kHz or higher supports bandwidths greater than 24.25 GHz to overcome phase noise.

[0085] The NR frequency band is defined by two types of frequency ranges: FR1 and FR2. FR1 is the sub-6GHz range, while FR2 is the above-6GHz range, which can refer to millimeter wave (mmW) frequencies.

[0086] Table 2 below illustrates the definition of NR frequency bands.

[0087]

[0088] With regard to the frame structure in the NR system, the sizes of the various fields in the time domain are is expressed as a multiple of the time unit. Here, And, is. Downlink and uplink transmissions are It consists of a radio frame having a period of . Here, each radio frame is It consists of 10 subframes with a duration of . In this case, there may be one set of frames for the uplink and one set of frames for the downlink.

[0089] Transmission of uplink frame number i from a terminal (User Equipment, UE) is earlier than the start of the corresponding downlink frame from that terminal. You have to start earlier.

[0090] Numerology Regarding slots, slots are located within a subframe. are numbered in increasing order within a wireless frame. are numbered in increasing order. One slot is It consists of consecutive OFDM symbols, is determined by the numerology and slot configuration used. In a subframe, the slot The start of an OFDM symbol in the same subframe It is aligned chronologically with the beginning of the .

[0091] Not all terminals can transmit and receive simultaneously, which means that not all OFDM symbols in a downlink slot or uplink slot can be utilized.

[0092] Table 3 shows the number of OFDM symbols per slot in normal CP. ), number of slots per wireless frame ( ), number of slots per subframe ( ), and Table 3 shows the number of OFDM symbols per slot, the number of slots per radio frame, and the number of slots per subframe in the extended CP.

[0093]

[0094]

[0095] Figure 1 illustrates an example of a frame structure in an NR system. Figure 1 is provided solely for convenience of explanation and does not limit the scope of the present specification.

[0096] In the case of Table 4, as an example when μ=2, that is, when the subcarrier spacing (SCS) is 60 kHz, referring to Table 3, 1 subframe (or frame) can include 4 slots, and 1 subframe={1,2,4} slots illustrated in FIG. 1 are an example, and the number of slot(s) that can be included in 1 subframe can be defined as in Table 3.

[0097] Additionally, a mini-slot may consist of 2, 4 or 7 symbols, or may consist of more or fewer symbols.

[0098] In relation to physical resources in the NR system, antenna ports, resource grids, resource elements, resource blocks, and carrier parts can be considered.

[0099] Below, we will look specifically at the above physical resources that can be considered in the NR system.

[0100] Figure 2 shows an example of a resource grid supported in NR.

[0101] Referring to Figure 2, for each subcarrier spacing setting and carrier, N size,μ grid *N RB sc Dog subcarriers and A resource grid of OFDM symbols is defined, where N size,μ grid is indicated by RRC signaling from BS. N size,μ grid The subcarrier spacing setting μ can vary between uplink and downlink as well.

[0102] Numerology One resource grid can be configured for each antenna port p. Numerology Each element of the resource grid for antenna port p is referred to as a resource element and has an index pair is uniquely identified by. Here, is the index in the frequency domain, refers to the position of a symbol within a subframe. When referring to a resource element in a slot, an index pair This is used. Here, am.

[0103] Numerology and resource elements for antenna port p is a complex value . In cases where there is no risk of confusion or where a specific antenna port or numerology is not specified, the indices p and can be dropped, resulting in a complex value or This can be. Also, the physical resource block is in the frequency domain. It is defined as consecutive subcarriers.

[0104] Considering that the UE may not be able to support the wide bandwidth supported by the NR system at once, the UE may be configured to operate in a part of the frequency bandwidth of the cell (hereinafter, bandwidth part (BWP)).

[0105] The resource blocks of the NR system include physical resource blocks defined within the bandwidth part and common resource blocks numbered upward from 0 in the frequency domain for the subcarrier spacing setting μ.

[0106] Point A serves as a common reference point of the resource block grid and can be obtained as follows.

[0107] - offsetToPointA for PCell downlink represents the frequency offset between point A and the lowest subcarrier of the lowest resource block overlapping the SS / PBCH block used by the UE for initial cell selection, expressed in resource block units assuming 15 kHz subcarrier spacing for FR1 and 60 kHz subcarrier spacing for FR2;

[0108] - absoluteFrequencyPointA represents the frequency-position of point A expressed as ARFCN (absolute radio-frequency channel number).

[0109] Common resource blocks set subcarrier spacing In the frequency domain, the numbers are numbered from 0 upwards.

[0110] Setting the subcarrier spacing The center of subcarrier 0 of common resource block 0 coincides with 'point A'. Common resource block number in the frequency domain and subcarrier spacing setting The resource elements (k,l) for can be given as in the mathematical expression 1 below.

[0111]

[0112] Here, Is It can be defined relative to point A to correspond to a subcarrier centered around this point A. The physical resource blocks are numbered from 0 within the bandwidth part (BWP). are numbered up to, is the number of BWP. Physical resource block in BWP i and common resource blocks The relationship between them can be given by the mathematical expression 2 below.

[0113]

[0114] Here, may be a common resource block where BWP starts relative to common resource block 0.

[0115] Bandwidth part (BWP)

[0116] In NR systems, up to 400 MHz can be supported per carrier. If a UE operating on such a wideband carrier always operates with the radio frequency (RF) module for the entire carrier turned on, the UE battery consumption may increase. Alternatively, when considering multiple use cases (e.g., eMBB, URLLC, mMTC, V2X, etc.) operating within a single wideband carrier, different numerologies (e.g., subcarrier spacing) may be supported for each frequency band within the carrier. Alternatively, each UE may have different capabilities for maximum bandwidth. Considering this, the BS may instruct the UE to operate only in a portion of the bandwidth of the wideband carrier, not the entire bandwidth, and this portion of bandwidth is called a bandwidth part (BWP). In the frequency domain, a BWP is the numerology μ within the bandwidth part i on the carrier. i A subset of contiguous common resource blocks defined for which one numerology (e.g., subcarrier spacing, CP length, slot / mini-slot duration) can be set.

[0117] Meanwhile, the BS can configure one or more BWPs within a single carrier assigned to the UE. Alternatively, if a specific BWP is overloaded with UEs, some UEs can be moved to other BWPs for load balancing. Alternatively, considering frequency domain inter-cell interference cancellation between neighboring cells, a portion of the overall bandwidth can be excluded and both BWPs on both sides of the cell can be configured within the same slot. That is, the BS can configure at least one DL / UL BWP for a UE associated with a wideband carrier, and can activate at least one DL / UL BWP among the configured DL / UL BWP(s) at a specific point in time (by L1 signaling, which is a physical layer control signal, a MAC control element (CE), which is a MAC layer control signal, or RRC signaling, etc.) and instruct switching to another configured DL / UL BWP (by L1 signaling, MAC CE, or RRC signaling, etc.), or can set a timer value so that the UE switches to the determined DL / UL BWP when the timer expires. An activated DL / UL BWP is specifically referred to as an active DL / UL BWP. The UE may not receive configuration for a DL / UL BWP in situations such as when the UE is in the initial access process or before the RRC connection of the UE is set up. In this situation, the DL / UL BWP assumed by the UE is called the initial active DL / UL BWP.

[0118] Physical channels and general signal transmission

[0119] Figure 3 illustrates the physical channels and typical signal transmission used in 3GPP systems. In a wireless communication system, a terminal receives information from a base station via the downlink (DL), and the terminal transmits information to the base station via the uplink (UL). The information transmitted and received between the base station and the terminal includes data and various control information, and various physical channels exist depending on the type and purpose of the information they transmit and receive.

[0120] When a terminal is powered on or enters a new cell, it performs an initial cell search operation, such as synchronizing with the base station (S301). To this end, the terminal receives a Primary Synchronization Signal (PSS) and a Secondary Synchronization Signal (SSS) from the base station to synchronize with the base station and obtain information such as a cell ID. Afterwards, the terminal can receive a Physical Broadcast Channel (PBCH) from the base station to obtain broadcast information within the cell. Meanwhile, the terminal can receive a Downlink Reference Signal (DL RS) during the initial cell search phase to check the downlink channel status.

[0121] A terminal that has completed initial cell search can obtain more specific system information by receiving a physical downlink control channel (PDCCH) and a physical downlink shared channel (PDSCH) according to information carried in the PDCCH (S302).

[0122] Meanwhile, when accessing a base station for the first time or when there are no radio resources for signal transmission, the terminal may perform a random access procedure (RACH) for the base station (S303 to S306). To this end, the terminal may transmit a specific sequence as a preamble via a physical random access channel (PRACH) (S303 and S305) and receive a response message (RAR (Random Access Response) message) to the preamble via a PDCCH and a corresponding PDSCH. In the case of a contention-based RACH, a contention resolution procedure may additionally be performed (S306).

[0123] A terminal that has performed the procedure described above can then perform PDCCH / PDSCH reception (S307) and physical uplink shared channel (PUSCH) / physical uplink control channel (PUCCH) transmission (S308) as a general uplink / downlink signal transmission procedure. In particular, the terminal can receive downlink control information (DCI) via PDCCH.

[0124] A UE monitors a set of PDCCH candidates in monitoring opportunities set in one or more control element sets (CORESETs) on a serving cell according to the corresponding search space configurations. The set of PDCCH candidates to be monitored by the UE is defined in terms of search space sets, and the search space set can be a common search space set or a UE-specific search space set. A CORESET consists of a set of (physical) resource blocks having a time duration of 1 to 3 OFDM symbols. The network can configure the UE to have multiple CORESETs. The UE monitors PDCCH candidates in one or more search space sets. Here, monitoring means attempting to decode the PDCCH candidate(s) in the search space. If the UE successfully decodes one of the PDCCH candidates in the search space, the UE determines that the PDCCH has been detected in the corresponding PDCCH candidate, and performs PDSCH reception or PUSCH transmission based on the DCI in the detected PDCCH.

[0125] The PDCCH can be used to schedule DL transmissions on the PDSCH and UL transmissions on the PUSCH. Here, the DCI on the PDCCH includes a downlink assignment (i.e., a DL grant) that includes at least modulation and coding format and resource allocation information related to a downlink shared channel, or an uplink grant that includes modulation and coding format and resource allocation information related to an uplink shared channel. The DCI has different formats depending on its intended use.

[0126] Meanwhile, the control information that the terminal transmits to the base station via the uplink or that the terminal receives from the base station may include downlink / uplink ACK / NACK signals, CQI (Channel Quality Indicator), PMI (Precoding Matrix Index), RI (Rank Indicator), etc. The terminal may transmit the above-described control information such as CQI / PMI / RI via PUSCH and / or PUCCH.

[0127] SSB (Synchronization Signal Block) transmission and related operations

[0128] Figure 4 is a diagram illustrating an SSB structure to which the method proposed in this specification can be applied. Based on SSB, the UE can perform cell search, system information acquisition, beam alignment for initial access, DL measurements, etc. SSB is used interchangeably with the SS / PBCH (Synchronization Signal / Physical Broadcast channel) block.

[0129] Referring to Figure 4, SSB is composed of PSS, SSS, and PBCH. SSB is composed of four consecutive OFDM symbols, and PSS, PBCH, SSS / PBCH, and PBCH are transmitted for each OFDM symbol. PSS and SSS are each composed of one OFDM symbol and 127 subcarriers, and PBCH is composed of three OFDM symbols and 576 subcarriers.

[0130] Polar coding and Quadrature Phase Shift Keying (QPSK) are applied to the PBCH. Each OFDM symbol consists of a data RE and a Demodulation Reference Signal (DMRS) RE. There are three DMRS REs per RB, and three data REs are located between the DMRS REs.

[0131] Figure 5 illustrates the transmission of a synchronization signal block (SSB) to which the method proposed in this specification can be applied.

[0132] SSB is transmitted periodically according to the SSB periodicity. The basic SSB period assumed by the UE during initial cell search is defined as 20ms. After cell access, the SSB period can be set by the network (e.g., base station) to one of {5ms, 10ms, 20ms, 40ms, 80ms, 160ms}. An SSB burst set is configured at the beginning of the SSB period. An SSB burst set consists of a 5ms time window (i.e., half-frame), and an SSB can be transmitted at most L times within the SSB burst set. The maximum number of SSB transmissions L can be given as follows depending on the frequency band of the carrier. One slot contains at most two SSBs.

[0133] - For frequency range up to 3 GHz, L = 4

[0134] - For frequency range from 3GHz to 6 GHz, L = 8

[0135] - For frequency range from 6 GHz to 52.6 GHz, L = 64

[0136] The temporal position of an SSB candidate within an SS burst set can be defined as follows according to the SCS. The temporal position of an SSB candidate is indexed from 0 to L-1 in temporal order within the SSB burst set (i.e., half-frame) (SSB index).

[0137] Multiple SSBs can be transmitted within the carrier frequency span. The physical layer cell identifiers of these SSBs need not be unique, and different SSBs can have different physical layer cell identifiers.

[0138] A UE can acquire DL synchronization by detecting an SSB. Based on the detected SSB (time) index, the UE can identify the structure of the SSB burst set, thereby detecting symbol / slot / half-frame boundaries. The frame / half-frame number to which the detected SSB belongs can be identified using the system frame number (SFN) information and half-frame indication information.

[0139] The above-mentioned content can be applied in combination with the methods proposed in this specification, which will be described later, or can be supplemented to clarify the technical characteristics of the methods proposed in this specification. The methods described below are distinguished for convenience of explanation, and it is understood that certain components of one method may be substituted for or combined with other methods.

[0140] Technical terms used in this specification

[0141] UE: User Equipment

[0142] SSB: Synchronization Signal Block

[0143] MIB: Master Information Block

[0144] RMSI: Remaining Minimum System Information

[0145] FR1: Frequency Range 1. Refers to the frequency range below 6 GHz (e.g., 450 MHz to 6000 MHz).

[0146] FR2: Frequency Range 2. Refers to the millimeter wave (mmWave) range above 24 GHz (e.g., 24250 MHz to 52600 MHz).

[0147] BW: Bandwidth

[0148] BWP: Bandwidth Part

[0149] RNTI: Radio Network Temporary Identifier

[0150] CRC: Cyclic Redundancy Check

[0151] SIB: System Information Block

[0152] SIB1: SIB1 for NR devices = RMSI (Remaining Minimum System Information). Broadcasts information necessary for NR terminals to access cells.

[0153] CORESET (COntrol REsource SET): Time / frequency resource for NR terminals to attempt candidate PDCCH decoding

[0154] CORESET#0: CORESET for Type0-PDCCH CSS set for NR devices (configured in MIB)

[0155] Type0-PDCCH CSS set: a search space set in which an NR UE monitors a set of PDCCH candidates for a DCI format with CRC scrambled by a SI-RNTI

[0156] MO: PDCCH Monitoring Occasion for Type0-PDCCH CSS set

[0157] SIB1-R: (additional) SIB1 for reduced capability NR devices. May be limited to cases where it is generated as a separate TB from SIB1 and transmitted on a separate PDSCH.

[0158] CORESET#0-R: CORESET#0 for reduced capability NR devices

[0159] Type0-PDCCH-R CSS set: a search space set in which an redcap UE monitors a set of PDCCH candidates for a DCI format with CRC scrambled by a SI-RNTI

[0160] MO-R: PDCCH Monitoring Occasion for Type0-PDCCH CSS set

[0161] Cell defining SSB (CD-SSB): SSB containing RMSI scheduling information among NR SSBs

[0162] Non-cell defining SSB (non-CD-SSB): An SSB placed in the NR sync raster but not containing RMSI scheduling information for the corresponding cell for measurement purposes. However, it may contain information indicating the location of the cell defining SSB.

[0163] SCS: subcarrier spacing

[0164] SI-RNTI: System Information Radio-Network Temporary Identifier

[0165] Camp on: "Camp on" is the UE state in which the UE stays on a cell and is ready to initiate a potential dedicated service or to receive an ongoing broadcast service.

[0166] TB: Transport Block

[0167] RSA (Redcap standalone): Redcap device 또는 service만 지원하는 cell.

[0168] SIB1(-R)-PDSCH: SIB1(-R)을 전송하는 PDSCH

[0169] SIB1(-R)-DCI: SIB1(-R)-PDSCH를 scheduling하는 DCI. DCI format 1_0 with CRC scrambled by SI-RNTI.

[0170] SIB1(-R)-PDCCH: SIB1(-R)-DCI를 전송하는 PDCCH

[0171] FDRA: Frequency Domain Resource Allocation

[0172] TDRA: Time Domain Resource Allocation (Time Domain Resource Assignment)

[0173] RA: Random Access

[0174] MSGA: preamble and payload transmissions of the random access procedure for 2-step RA type.

[0175] MSGB: response to MSGA in the 2-step random access procedure. MSGB may consist of response(s) for contention resolution, fallback indication(s), and backoff indication.

[0176] RO-N: normal UE 4-step RACH and 2-step RACH(if configured)를 위한 RO(RACH Occasion)

[0177] RO-N1, RO-N2: When a separate RO is set for normal UE 2-step RACH, it is divided into RO-N1 (4-step) and RO-N2 (2-step).

[0178] RO-R: RO (RACH Occasion) set separately from RO-N for redcap UE 4-step RACH and 2-step RACH (if configured)

[0179] RO-R1, RO-R2: When separate ROs are set for redcap UE 2-step RACH, they are distinguished as RO-R1 (4-step) and RO-R2 (2-step).

[0180] PG-R: MsgA-Preambles Group for redcap UEs

[0181] RAR: Random Access Response

[0182] RAR window: the time window to monitor RA response(s)

[0183] FH: Frequency Hopping

[0184] iBWP: initial BWP

[0185] iBWP-DL(-UL): initial DL(UL) BWP

[0186] iBWP-DL(-UL)-R: (separate) initial DL(UL) BWP for RedCap

[0187] CS: Cyclic shift

[0188] NB: Narrowband

[0189] TO: Traffic Offloading

[0190] mTC; Massive Machine Type Communications

[0191] eMBB: enhanced Mobile Broadband Communication

[0192] URLLC: Ultra-Reliable and Low Latency Communication

[0193] RedCap: Reduced Capability

[0194] eRedCap: enhanced RedCap

[0195] FDD: Frequency Division Duplex

[0196] HD-FDD: Half-Duplex-FDD

[0197] DRX: Discontinuous Reception

[0198] RRC: Radio Resource Control

[0199] RRM: Radio Resource Management

[0200] IWSN: Industrial Wireless Sensor Network

[0201] LPWA: Low Power Wide Area

[0202] RB: Resource Block

[0203] CCE: Control Channel Element

[0204] AL: Aggregation Level

[0205] PRG: Physical Resource-block Group

[0206] DFT-s-OFDM: DFT-spread OFDM

[0207] PBCH: Physical Broadcast Channel

[0208] A-PBCH: Additional PBCH

[0209] BD: blind detection

[0210] EPRE: Energy Per RE

[0211] SNR: Signal-to-Noise Ratio

[0212] TDM: Time Division Multiplexing

[0213] DMRS: DeModulation Reference Signal

[0214] TDD: Time Division Duplex

[0215] In this specification, '()' can be interpreted as either excluding the contents within () or including the contents within the parentheses.

[0216] In this specification, ' / ' may mean including all of the contents separated by / (and) or including only some of the contents separated by / (or).

[0217] 5G wireless communication systems are characterized by their ability to effectively support use cases such as mMTC, eMBB, and URLLC compared to previous generations (e.g., LTE, GSM). Due to these advantages, 5G wireless communication systems are expected to create new use cases while gradually replacing previous-generation wireless communication systems for various use cases.

[0218] The improved low latency, high reliability, massive connection, and other features of the 5G wireless communication system can be applied to use cases (hereinafter referred to as NB use cases) previously supported by narrowband (NB), as follows.

[0219] [Examples of narrowband-based use cases (NB use cases)]

[0220] i) Railway mobile communication

[0221] ii) Utility / infrastructure network

[0222] iii) Wireless communications for public safety

[0223] These NB use cases were previously supported in the sub-1 GHz frequency band with a bandwidth of approximately 3 MHz using previous-generation wireless communication systems. Similarly, when trying to support the above NB use cases with a 5G wireless communication system, for example, it can be supported with a similar frequency bandwidth (approximately 3 MHz to less than 5 MHz) in the same (sub-1 GHz) frequency band. However, since the minimum channel BW supported by the current 5G NR standard is 5 MHz, to achieve this, a channel bandwidth of less than 5 MHz must first be supported.

[0224] [Examples of 5G NR frequency bands for supporting NB use cases (TS38.101-1)]

[0225] NB use cases can be supported in the following NR operating frequency bands defined in the NR standard TS38.101-1.

[0226]

[0227] Table 5 shows the UL / DL operating bands defined by NR operating bands in Frequency Range 1 (FR1).

[0228] [Example of defining a channel BW of less than 5 MHz to support NB use cases]

[0229] Table 6 shows the maximum number of RBs (N) that can be set for each UE channel BW. RB) is an example. According to Table 6, in order to support NB use cases based on 5G NR, 3 MHz UE channel BW and the maximum number of RBs that can be set at this time (N RB )(15) is defined, and the resource utilization ratio (or RU)(%) at this time is defined.

[0230]

[0231] In addition, for the newly defined 3 MHz UE channel BW, considering interference between adjacent channels and resource utilization, other N RB It is also possible to define and use values.

[0232]

[0233] For example, channel BW / N RB The same value can be applied to both DL and UL. For example, channel BW / N can be applied separately / independently to DL and UL. RB can be set / supported. The method according to the second example can be applied to the following situations: Both DL and UL should consider adjacent channel interference and resource utilization to maximize channel BW / N. RB Supports values, but N RB It can be used when you want to apply additional conditions for DFT precoding to UL only when determining the value.

[0234] FIG. 6 is a flowchart illustrating DL signal / channel reception during the initial connection process to which a method according to an embodiment of the present disclosure may be applied. Referring to FIG. 6 , a 5G NR terminal may receive DL signals / channels in the order of S610 to S640 during the initial connection process. The specific details of the initial connection process are identical to those described in FIGS. 3 to 5 , and thus, redundant descriptions are omitted.

[0235] Conventional NR terminals can receive CORESET#0 information via the MIB (Master Information Block) transmitted via the PBCH and receive initial DL signals / channels via the CORESET#0 frequency band during the initial connection process. However, considering the channel BWs exemplified in Tables 6 and 7 and the CORESET#0 bandwidths supported by the NR standard, the operation according to the conventional method described above may be inefficient in narrowband.

[0236] Considering such circumstances, the present invention proposes methods for effectively supporting a DL control channel for initial access in a narrowband.

[0237] In this specification, the terms narrowband, narrowband, and NB can be interpreted and applied interchangeably. In addition, channel BW, NRB, allowed / supported transmission BW, (punctured / non-punctured) PBCH BW, and maximum transmission BW can also be interpreted and applied interchangeably.

[0238] In this specification, broadcast signaling includes system information including SIB1, MIB, PBCH payload generated in the PHY layer in addition to MIB, and signaling methods using PBCH scrambling sequence and PBCH DMRS sequence initialization information.

[0239] In this specification, broadcast signaling may include cases where existing bits / fields are defined or interpreted differently. For example, in cases where some of the signaling methods using MIB, PBCH payload generated in the PHY layer in addition to MIB, PBCH scrambling sequence, and PBCH DMRS sequence initialization information that were previously used for broadcast signaling no longer require signaling, this may include cases where the corresponding bits / fields are newly defined and signaled. For example, in a narrowband frequency band that only supports 15 kHz SCS, this may include using subCarrierSpacingCommon in MIB (1 bit, {15 kHz, 30 kHz}) for other 1-bit broadcast signaling purposes. In addition, if PBCH / SIB1 / SIB1-scheduling DCI transmission for new terminals is possible without affecting legacy terminals due to frequency bands, dedicated spectrum, dedicated sync raster, etc., the above-described broadcast signaling may include a method of signaling by newly defining or interpreting differently bits / fields that were previously used for broadcast signaling purposes for legacy terminals.

[0240] [PBCH transmission method in narrowband]

[0241] In order to support reception of NR DL broadcast signals in a narrowband having a bandwidth of < 5 MHz, a subset of PBCH transmission RBs (Resource Blocks) may be transmitted. In this specification, 'transmitting a subset of PBCH transmission RBs' may mean 'transmitting the corresponding PBCH based on a subset of RBs allocated to the PBCH.'

[0242] In this specification, PBCH transmission RB may refer to RBs associated with the PBCH or RBs allocated to the PBCH in the time-frequency structure of the SS / PBCH (e.g., FIG. 7). In this specification, 'PBCH transmission RB subset' may refer to a portion of RBs associated with the PBCH or a portion of RBs allocated to the PBCH.

[0243] In this specification, PSS / SSS transmission RB may mean RBs related to PSS / SSS or RBs allocated to PSS / SSS in the time-frequency structure of SS / PBCH (e.g., FIG. 7).

[0244] In this specification, a Resource Block (RB) may be interpreted / replaced with a Physical Resource Block (PRB) or a Common Resource Block (CRB).

[0245] Figure 7 illustrates the time-frequency structure of SSB according to one embodiment of the present specification. As an example, the time / frequency structure of SSB may be defined in the NR standard.

[0246] Specifically, FIG. 7 additionally displays the number of REs / RBs for each domain in the time / frequency structure of FIG. 4. Referring to FIG. 7, the frequency domain (bandwidth) for PSS and SSS consists of 127 resource elements (REs). The frequency domain (bandwidth) for PBCH consists of 20 resource blocks (RBs) (= 144 REs) or 4 resource blocks (4 RBs) (= 48 REs).

[0247] For example, N RB = In order to support PBCH transmission and reception in a 3 MHz channel BW defined as 15 PRBs, the base station may need to transmit at least 5 PBCH transmission RBs by excluding or puncturing them among the PBCH consisting of 20 PRBs. In other words, a subset of up to 15 PBCH transmission RBs may be transmitted among the total 20 PBCH transmission RBs. In addition, in order to achieve the same level of synchronization and measurement performance as a conventional NR terminal, the PSS / SSS transmission RBs may be transmitted in their entirety. In this case, the minimum PBCH transmission RBs may be 12 RBs including PSS / SSS.

[0248] In this specification, a "punctured" PBCH or PBCH transmission RB subset refers to the PBCH actually transmitted after puncturing is applied when transmitting by puncturing a portion of the PBCH transmission RBs. Therefore, the terms "punctured PBCH" and "PBCH transmission RB subset" can be interpreted and applied interchangeably.

[0249] As in the example above, N RB= In a 3 MHz channel BW defined as 15 PRBs, the base station / terminal can configure the PBCH transmission RB subset to 12 PRBs to 15 PRBs. Hereinafter, methods for configuring the PBCH transmission RB subset to 12 PRBs and 15 PRBs, respectively, are described in detail.

[0250] [Example #P1]

[0251] A method of configuring a PBCH transmission RB subset with 12 PRBs including PSS / SSS may be considered.

[0252] Example #P1 is a case where the PBCH transmission RB subset is configured with only 12 PRBs including PSS / SSS. In other words, the PBCH transmission RB subset can be configured with a minimum RB subset that includes the entire PSS / SSS (e.g., FIG. 8). Example #P1 can be useful when defining a single punctured PBCH or PBCH transmission RB subset to be applied to various narrowband channel BWs.

[0253] FIG. 8 illustrates a frequency resource region for PBCH transmission and reception according to one embodiment of the present specification. Specifically, FIG. 8 illustrates a PBCH transmission RB subset based on Example #P1.

[0254] [Example #P2]

[0255] A method of configuring a PBCH transmission RB subset with 15 PRBs including PSS / SSS may be considered.

[0256] Example #P2 is a case where the PBCH transmission RB subset is configured with 15 PRBs including PSS / SSS.

[0257] The PBCH transmission RB subset (i.e., detailed configuration of 15 PRBs) according to the present embodiment can be determined based on one of the configurations (#P2-1 to #P2-4).

[0258] Configuration #P2-1: Center 12 PRB (for PSS / SSS) + lower 3 PRB

[0259] Configuration #P2-2: Center 12 PRB (for PSS / SSS) + higher 3 PRB

[0260] Configuration #P2-3: Center 12 PRB (for PSS / SSS) + lower 2 PRB + higher 1 PRB

[0261] Configuration #P2-4: Center 12 PRB (for PSS / SSS) + higher 2 PRB + lower 1 PRB

[0262] Due to the nature of PBCH RE mapping, prioritizing lower RBs among PBCH transmission RBs may have a small performance advantage. Therefore, all other conditions being equal, configuration #P2-1 may have an advantage over configuration #P2-2 in terms of PBCH reception performance. Furthermore, configuration #P2-3 may have an advantage over configuration #P2-4 in terms of PBCH reception performance.

[0263] Additionally, configurations #P2-1 and #P2-2 may be affected in terms of sync performance and measurement performance in situations where adjacent channel / frequency interference exists because the PSS / SSS is exposed to the band edge. If such interference is expected, configuration #P2-3 or #2-4 may be considered. Configuration #P2-3 or #2-4 may be intended to protect against adjacent channel / frequency band interference by placing the PSS / SSS further inside the channel BW. This will be described below with reference to FIG. 9.

[0264] FIG. 9 illustrates a frequency resource region for PBCH transmission and reception according to another embodiment of the present specification.

[0265] Figure 9 (a) illustrates configuration #P2-1. In this case, the PBCH transmission RB subset may include Center 12 PRBs (for PSS / SSS) + lower 3 PRBs.

[0266] Figure 9 (b) illustrates configuration #P2-3. In this case, the PBCH transmission RB subset may include Center 12 PRBs (for PSS / SSS) + lower 2 PRBs + higher 1 PRB.

[0267] PDCCH transmission and reception method

[0268] In order to receive SIB1-PDCCH in a narrowband, the UE can receive CORESET#0 and Type0-PDCCH CSS set information through the MIB transmitted through the PBCH. Since the CORESET#0 bandwidth currently supported by the NR standard is 24 PRB (4.32 MHz) based on 15 kHz SCS, it can exceed the narrowband channel BWs exemplified in Tables 6 and 7. In this case, the base station can map REs to CORESET#0 and then transmit PDCCH only for REs within the channel BW. In other words, REs exceeding the channel BW can be punctured / truncated so that PDCCH can be transmitted only based on REs within the channel BW.

[0269] When PDCCH cannot be transmitted in the entire CORESET#0 BW for narrowband transmission / reception, REs for actual PDCCH transmission / reception may be determined in specific units in the frequency domain. The specific units may include RE units, PRB units, REG units, REG bundle units, or CCE units. When determined in CCE units, in the case of 3-symbol CORESET#0, whether to actually transmit / receive PDCCH (or whether to puncture / truncate) may be determined in units of 2 PRBs. Alternatively, in the case of 2-symbol CORESET#0, REs for actual PDCCH transmission / reception may be determined in units of 3 PRBs.

[0270] The terminal can receive the PDCCH in REs within the channel BW assuming the above-mentioned base station operation (i.e., puncturing / truncation operation). That is, according to the NR standard, not all REs mapped to the CORESET#0 bandwidth are utilized for PDCCH transmission and reception. The terminal / base station can assume that only REs within the channel BW among the REs are utilized for actual PDCCH transmission and reception and operate based on this.

[0271] Alternatively, the terminal may receive the PDCCH in REs within the PBCH BW, assuming the above-described base station operation (i.e., puncturing operation). That is, not all REs mapped to the CORESET#0 bandwidth according to the NR standard are utilized for PDCCH transmission and reception. The terminal / base station may assume that among the mapped REs, only REs belonging to the PBCH BW are actually utilized for PDCCH transmission and reception.

[0272] At this time, the PBCH BW in which the terminal expects PDCCH reception may be the PBCH BW "used for actual PBCH transmission." That is, the PBCH BW used for actual PBCH transmission may refer to the PBCH BW "used for actual PBCH transmission after puncturing" when some of the RBs for PBCH transmission are punctured and the PBCH is transmitted. The "punctured" PBCH BW may be assumed to be the initial DL BW.

[0273] Also, in this case, if the CORESET#0 BW exceeds the channel BW during the initial connection process, the terminal may assume the PBCH BW as the initial DL BWP. In this case, the PBCH BW assumed by the terminal as the initial DL BWP may be the PBCH BW "used for actual PBCH transmission." That is, if some of the PBCH transmission RBs are punctured and transmitted, the PBCH BW assumed as the initial DL BWP may be the PBCH BW "used for actual PBCH transmission after puncturing." Or, in the same sense, the "punctured" PBCH BW may be assumed as the initial DL BWP.

[0274] The reason for redefining the initial DL BWP in this way in the narrowband may be to eliminate factors that may cause terminal complexity issues or adverse effects on reception coverage, such as puncturing or partial reception, within the initial DL BWP.

[0275] Figure 10 is a diagram illustrating a frequency domain related to PDCCH transmission and reception.

[0276] Referring to Fig. 10, N RB = 16 PRB, CORESET#0 BW = 24 PRB, it is assumed that the higher 4 PRBs of the PBCH are transmitted by puncturing.

[0277] Figure 10 shows the frequency range and initial DL BWP in which the terminal expects PDCCH reception among CORESET#0 BW.

[0278] Also, three CORESET#0s are illustrated in FIG. 10. The three CORESET#0s are CORESET#0s with a size of 24 PRBs among the CORESET#0s that the base station can set / display through the current NR standard TS 38.213 Table 13-1. The three CORESET#0s have different RB offset values ​​(as defined in TS 38.213 Table 13-1). However, for the CORESET#0s, PDCCH transmission and reception are expected to be performed in REs of similar degrees within the maximum transmission BW or PBCH BW. Since there may not be a significant difference in terms of performance, all three CORESET#0s can be supported.

[0279] The position of CORESET#0 can be defined / determined relative to SSB. Specifically, the relative position of CORESET#0 can be determined as shown in Table 8 below. That is, the interval between CORESET#0 and SSB is determined by the offset parameter (RB offset) and It can be determined based on the parameter (subcarrier offset).

[0280]

[0281] may be indicated by the ssb-SubcarrierOffset parameter within the system information block (e.g., MIB). For example, can be indicated by an integer between 0 and 15. If the ssb-SubcarrierOffset parameter is not set, can be derived from the frequency difference between SS / PBCH block and Point A.

[0282] Above The parameters may be defined based on one of the embodiments described below (e.g., method #A, method #B). For example, the above Parameters can be defined based on SS / PBCH blocks in the same way as the existing method (method #A). For example, Parameters can be defined based on the SS / PBCH block after puncturing (method #B). Referring to FIGS. 11 and 12 below. Describe Point A in relation to the parameters.

[0283] Fig. 11 is a diagram illustrating Point A according to the conventional method. Specifically, Fig. 11 illustrates offsetToPointA. Referring to Fig. 11, offsetToPoint A represents a frequency offset between Point A and the lowest subcarrier (subcarrier 0) of the lowest resource block (CRB #8) overlapping with the SS / PBCH block. is the lowest numbered subcarrier (subcarrier 0) of the SS / PBCH block and the common resource block ( ) represents the subcarrier offset between subcarrier 0 and subcarrier 0. Here, the common resource block ( ) can be obtained from offsetToPointA. That is, the common resource block ( ) may be the lowest resource block overlapping with the SS / PBCH block based on offsetToPointA.

[0284] Fig. 12 is a drawing illustrating Point A according to an embodiment of the present specification. The description overlapping with Fig. 11 is omitted. Referring to Fig. 12, the SS / PBCH block after puncturing may be composed of 12 resource blocks. According to the embodiment of the present specification, offsetToPoint A is the lowest resource block ( , CRB #12) represents the frequency offset between the lowest subcarrier (subcarrier 0).

[0285] Hereinafter, examples of relevant criteria related to the relative position of CORESET#0 (e.g., offset in Table 8) in Methods #A to #C will be examined.

[0286] [Method #A]

[0287] Even when transmitting PBCH and PDCCH in a narrowband based on the methods proposed in this specification, the relative positional relationship between SSB and CORESET#0 and the signaling method therefor can follow the conventional standard. That is, "the smallest RB index of the CORESET for Type0-PDCCH CSS set", "the first RB of the corresponding SS / PBCH block", etc. described in the above standard can be defined based on the SSB(PBCH) / CORESET #0 BW before puncturing.

[0288] Specifically, even if actual transmission / reception is not performed due to subset transmission, puncturing, etc. for narrowband transmission, the offset in Table 8 can be defined based on the entire PBCH BW (before puncturing) and the entire CORESET#0 BW (before puncturing).

[0289] [Method #B]

[0290] The above-described "first RB of the corresponding SS / PBCH block" may be defined based on the PBCH transmission RB that is actually transmitted / received. The PBCH transmission RB that is actually transmitted / received may refer to the RB after puncturing (or subset determination).

[0291] That is, the offset in Table 8 can be defined based on the punctured PBCH (i.e., SS / PBCH block after puncturing).

[0292] For example, in the case of a 12-RB PBCH, the “first RB of the corresponding SS / PBCH block” may mean one of the following i) to iv).

[0293] i)"the first RB of the corresponding "(actually) transmitted" SS / PBCH block"

[0294] ii)"the first RB of the corresponding SS / PBCH block after puncturing"

[0295] iii) “the first RB of the corresponding “non-punctured” SS / PBCH block”,

[0296] iv) “the subcarrier number 48 of the corresponding SS / PBCH block”

[0297] For narrowband transmission, rather than reusing the existing NR standard TS 38.213 Table 13-1, a new CORESET#0 configuration may be added. For example, the bandwidth of the added / introduced CORESET#0 for narrowband transmission may be less than or equal to the channel BW. Alternatively, even if the bandwidth of the added / introduced CORESET#0 is greater than the channel BW, it may be less than the bandwidth of the existing CORESET#0. For example, the following CORESET#0 configurations may be added.

[0298] - CORESET#0 size = 12 PRBs (for 15 PRB channel BW)

[0299] In this case, a maximum of 4 total CCEs (12 REGs per OFDM symbols * 2 OFDM symbols = 24 REGs = 4 CCEs) can be supported using 2 OFDM symbols. Therefore, 4 CCE AL support may be possible.

[0300] - CORESET#0 size = 18 PRBs (for 20 PRB channel BW)

[0301] In this case, up to 9 total CCEs (18 REGs per OFDM symbols * 3 OFDM symbols = 54 REGs = 9 CCEs) can be supported using 3 OFDM symbols. Conventional 8 CCE AL support may be possible.

[0302] The above-described CORESET#0 is explained below with reference to Figure 13.

[0303] Fig. 13 is a diagram illustrating CORESET#0 based on an embodiment of the present specification. Referring to Fig. 13, when a 12-RB PBCH is supported in a narrowband with a transmission BW of 12 PRBs, CORESET#0 with a CORESET#0 size of 12 PRBs can be applied.

[0304] At this time, the RB offset value (offset in Table 8) can be defined as follows.

[0305] For example, the RB offset value can be 0. That is, the smallest RB index of the CRB that overlaps the smallest RB index (index of the first RB) of the punctured SSB can be aligned with the smallest RB index of CORESET#0.

[0306] For example, if a punctured PBCH occupies the entire maximum transmission BW, or if CORESET#0 is for non-puncturing transmission within the maximum transmission BW and / or punctured PBCH BW, the RB offset value may be defined as follows: The RB offset value may be defined as a value such that the "highest" RB index of the CRB overlapping the smallest RB index of the punctured SSB aligns with the CORESET#0 smallest RB index.

[0307] To support the example of Fig. 13 through method #A, the RB offset value can be defined as a negative (-) value. Specifically, when the RB offset value is -4, the smallest RB index of the CRB that overlaps the smallest RB index of the punctured SSB can be aligned with the smallest RB index of CORESET#0.

[0308] [Method #C]

[0309] The above-described offset may be defined based on the smallest RB index according to a different criterion from that of non-punctured PBCH (method #A) / punctured PBCH (method #B). The offset may be defined based on the smallest RB index among RBs (or CRBs) defined or capable of DL reception within the maximum transmission BW. In this case, according to the offset value 0, the smallest RB index among RBs (or CRBs) defined or capable of DL reception within the maximum transmission BW and the smallest RB index of CORESET#0 may be aligned.

[0310] Parameters supporting the above methods (methods #A / B / C) can be indicated / configured via broadcast signaling (e.g., MIB). These parameters may include some or all of the parameters, such as the applied method and offset, among the above methods.

[0311] In one embodiment, the highest RB index of CORESET#0 can be determined without separate signaling. For example, the highest RB index of CORESET#0 can be determined based on the biggest RB index (highest RB index) of the CRB that does not exceed the maximum transmission BW. For example, the highest RB index of CORESET#0 can be determined based on the biggest RB index (highest RB index) of the CRB that does not exceed the punctured PBCH BW.

[0312] At this time, the highest RB index of CORESET#0 can be determined in units of RB / REG / REG bundle / CCE. If the highest RB index of CORESET#0 is configured in units of REG bundle / CCE, the total number of RBs of CORESET#0 can be limited to a multiple of the number of RBs that constitute the REG bundle / CCE.

[0313] In one embodiment, the CORESET#0 highest RB index can be set via broadcast signaling. For example, the base station can instruct / set one of the supportable CORESET#0 BW values ​​predefined in the standard to the terminal based on broadcast signaling. The CORESET#0 BW supported in the narrowband may be a BW size not supported by legacy terminals, and new terminals supporting narrowband operation may be configured / implemented to mandatorily support the CORESET#0 BW size supported in the narrowband.

[0314] As shown in Table 9 below, the PDCCH consists of one or more CCE(s).

[0315]

[0316] The CCEs that make up the PDCCH are mapped to the CORESET and transmitted according to the procedure specified below. Specifically, non-interleaved CCE-to-REG mapping or interleaved CCE-to-REG mapping can be applied. For example, non-interleaved CCE-to-REG mapping can be applied to obtain frequency selective scheduling gains. For example, interleaved CCE-to-REG mapping can be applied to obtain frequency diversity gains. In the case of CORESET#0, since it is difficult to expect frequency selective scheduling gains, only interleaved CCE-to-REG mapping is supported without separate configuration.

[0317] 7.3.2.2 Control-resource set (CORESET)

[0318] Control Resource Set (CORESET) in the frequency domain In the resource blocks and time domain of the dog It consists of dog symbols.

[0319] A Control Channel Element (CCE) consists of six Resource Element Groups (REGs), where a REG is equivalent to one Resource Block (RB) for one OFDM symbol. The REGs within a CCE are numbered in increasing time-first order, starting with 0 for the first OFDM symbol and the lowest-numbered RB in the CCE.

[0320] A UE can be configured with multiple control resource sets. Each control resource set is associated with only one CCE-to-REG mapping.

[0321] The CCE-REG mapping for a control resource set may or may not be interleaved and is described by a REG bundle:

[0322] - REG bundle are REGs is defined as, where, is the REG bundle size, and, is the number of REGs in CORESET.

[0323] - CCE j is REG bundles It consists of, where is an interleaver.

[0324] For non-interleaved CCE-to-REG mapping, =6, am.

[0325] About interleaved CCE-to-REG mapping, for =1, for The above interleaver is defined as follows.

[0326]

[0327]

[0328]

[0329]

[0330]

[0331] Here, .

[0332] UE is quantity It is not expected to handle non-integer configurations.

[0333] For the CORESET set by ControlResourceSet IE:

[0334] - is given by the upper layer parameter frequencyDomainResources;

[0335] - is given by the upper layer parameter duration, where, =3 is supported only when the upper layer parameter dmrs-TypeA-Position is 3;

[0336] - Interleaved or non-interleaved mapping is given by the upper layer parameter cce-REG-MappingType;

[0337] - is 6 for non-interleaved mapping and is given by the upper layer parameter reg-BundleSize for interleaved mapping;

[0338] - is given by the upper layer parameter interleaverSize;

[0339] - is given by the upper layer parameter shiftIndex if set, otherwise ;

[0340] - For interleaved mapping and non-interleaved mapping, the UE assumes the following:

[0341] - If the upper layer parameter precoderGranularity is equal to sameAsREG-bundle, the same precoding is used within the REG bundle;

[0342] - When the upper layer parameter precoderGranularity is equal to allContiguousRBs, the same precoding is used for all resource element groups within the contiguous resource block set of the CORESET, and the resource elements of the CORESET do not overlap with SSB or LTE cell-specific reference signals as indicated by the upper layer parameters lte-CRS-ToMatchAround, lte-CRS-PatternList1 or lte-CRS-PatternList2.

[0343] ControlResourceSetZero For CORESET 0 set by IE:

[0344] - and is defined by clause 13 of [5, TS 38.213];

[0345] - The UE assumes the following for interleaved mapping:

[0346] - =6;

[0347] - =2;

[0348] -

[0349] - The UE can assume the normal cyclic prefix if CORESET 0 is configured by MIB or SIB1.

[0350] - The UE can assume that the same precoding is used within the REG bundle.

[0351] As mentioned earlier, the narrowband channel BW may be smaller than the minimum bandwidth of the conventional CORESET#0, which is designed considering the general bandwidth. In such cases, the CORESET#0 bandwidth may exceed the narrowband channel BW. For example, since the CORESET#0 bandwidth supported by the current NR standard is 24 PRB (4.32 MHz) based on 15 kHz SCS, it may exceed the narrowband channel BWs exemplified in Tables 6 and 7. To support such scenarios, the following two methods have been proposed.

[0352] [Method #1] How to use New CORESET#0

[0353] A new CORESET#0 with a small bandwidth within the narrowband channel BW can be defined. PDCCH can be transmitted based on the newly defined CORESET#0.

[0354] [Method #1 Example #1] To support 3 MHz channel bandwidth, a new CORESET#0 with a bandwidth of 12 PRB, which is smaller than the conventional minimum bandwidth of 24 PRB, can be defined.

[0355] [Method #2] Conventional CORESET#0 reuse method

[0356] The PDCCH can be transmitted by reusing the existing CORESET#0, but excluding the resource area where RE is mapped beyond the narrowband channel BW. For example, puncturing (truncation) can be performed on RBs exceeding the narrowband channel BW (e.g., 3 MHz, 15 PRB). As a specific example, the frequency domain size ( ) is 24, CORESET#0 can be obtained by puncturing the 9 highest numbered RBs among the 24 RBs.

[0357] For example, the base station can perform PDCCH RE mapping according to the conventional method specified in TS 38.213 for the entire conventional CORESET#0 bandwidth. The base station can transmit the PDCCH based on the PDCCH transmission REs / RBs / REGs / REG bundles / CCEs included within the narrowband channel BW. In this case, the meaning of "included" can include the meaning of "partially included" or "included entirely."

[0358] [Method #2 Example #1] To support 3 MHz channel bandwidth, 24-PRB CORESET#0 defined in TS 38.213 Table 13-1 can be reused. In this case, PDCCH transmission RE / RB / REG / REG bundle / CCEs that are RE mapped beyond 3 MHz bandwidth (e.g., 15 PRBs based on 15 kHz SCS) may not be transmitted through puncturing / truncation, or terminal reception may not be expected / requested. For example, the highest / lowest 9 RBs (or 12 RBs) among 24-PRBs may be punctured.

[0359] In the narrowband scenario, when the above method #2 (conventional CORESET#0 reuse method) is applied, the interleaved CCE-to-REG mapping method specified in 7.3.2.2 described in CORESET#0 is applied by default or can be applied by configuration. This interleaving operation can be applied before performing the puncturing / truncation operation according to method #2 (conventional CORESET#0 reuse method). As defined in the standard. Depending on the parameter value, the number of CCEs included in the channel bandwidth (actually transmitted) may vary. This is because the parameter value has the effect of cyclically shifting the CCE indices mapped to each REG bundle on the frequency axis in units of REG bundles.

[0360] For interleaved CCE-to-REG mapping of CORESET#0 The parameter value is fixed to the cell ID as described above (i.e., ) As a result, the number of CCEs through which the actual PDCCH is transmitted varies depending on the cell ID in the same CCE AL (Aggregation Level) setting. Therefore, a problem may arise in which the variability in PDCCH transmission performance through CORESET#0 increases for each cell.

[0361] To solve / mitigate the above cell ID dependent PDCCH performance variability problem, the following methods are proposed.

[0362] [Method #1]

[0363] Cyclic shift value (i.e., A method of broadcast signaling information related to parameter values ​​or cyclic shifts may be considered.

[0364] The base station has a cyclic shift value ( ) or cyclic shift related information can be transmitted using broadcast signaling. For example, the cyclic shift value ( The parameter value) or cyclic shift related information may be determined based on at least one of the cell ID information operated by the base station, CORESET#0 puncturing / truncation information (method #2), and channel BW information.

[0365] For example, the Cyclic shift value ( parameter value) is for the conventional CORESET#0. It can be a value applied by replacing the cell ID value, which is a parameter value.

[0366] For example, cyclic shift related information may indicate an additional value (cyclic shift offset value) in addition to the conventional setting value (cell ID value in case of CORESET#0). In this case, = It can be applied in the +offset form.

[0367] For example, the cyclic shift value or the cyclic shift related information (e.g., cyclic shift offset) may be indicated based on N-bits (e.g., N=1, 2, ...). In this case, the cyclic shift value or cyclic shift offset based on the N-bits may be indicated at intervals of 1 / (2^N) of the CORESET#0 bandwidth.

[0368] For example, the Cyclic shift value (i.e., Parameter value) or cyclic shift related information can be added as a parameter to the CORESET#0 Table (e.g., TS 38.213 Table 13-1 or new CORESET#0 Table 13-X). The corresponding value can be indicated based on broadcast signaling. As a specific example, an index (e.g., 0 to 15) indicating one of the settings of CORESET#0 can be indicated based on the broadcast signaling. The Cyclic shift value (i.e., ) or cyclic shift related information can be determined.

[0369] [Method #2]

[0370] A method may be considered to determine the cyclic shift value by linking it to the CORESET#0 puncturing pattern without separate signaling.

[0371] That is, considering the very limited broadcast signaling capacity in the PBCH phase, it may be considered to define / set the cyclic shift value so that it is determined without separate signaling. This is explained in detail below.

[0372] Linked to the CORESET#0 puncturing pattern, without separate signaling, the cyclic shift value ( ) or cyclic shift related information can be determined.

[0373] The base station sets the cyclic shift value ( ) based on at least one of i) the cell ID information it operates, ii) CORESET#0 puncturing / truncation information in case of method #2 (conventional CORESET#0 reuse method), and / or iii) channel BW information. The parameter value) or cyclic shift offset value can be determined. Mapping related to CORESET#0 can be performed based on the determined cyclic shift value (n_shift parameter value) or cyclic shift offset value. The base station can transmit the PDCCH through the corresponding CORESET#0.

[0374] The terminal, in the same manner as the base station, uses the cyclic shift value ( (parameter value) or cyclic shift offset value can be determined. The terminal can receive the PDCCH through the corresponding CORESET#0. In order to obtain CORESET#0 puncturing / truncation information, the terminal can refer to information such as CORESET#0 configuration information of MIB, CORESET#0 Table (e.g., TS 38.213 Table 13-1 or 13-0), frequency band information, sync raster information of the cell that acquired SSB (if narrowband discrimination is possible through dedicated sync raster), etc. For example, the terminal can obtain / determine the CORESET#0 puncturing / truncation information based on at least one of i) CORESET#0 configuration information based on MIB, ii) frequency band information, and / or iii) sync raster information of the cell that acquired SSB.

[0375] For example, similar to method #1, the cyclic shift value or cyclic shift offset value can be determined based on the CORESET#0 puncturing pattern. As a specific example, the cyclic shift value or cyclic shift offset value can be determined at intervals of 1 / (2^N) (e.g., N=1,2,...) of the CORESET#0 bandwidth.

[0376] [Method #3]

[0377] A method of varying the cyclic shift value over time may be considered.

[0378] That is, in order to equalize the performance of PDCCH transmitted through CORESET#0 between cells, the cyclic shift value ( A method of varying the parameter value) or the cyclic shift offset value may be considered.

[0379] The time-varying unit can be i) a slot unit, ii) a slot group unit that groups multiple slots into a specific unit (e.g., 10 slots), iii) a specific time unit (e.g., X ms, eg, X=20 ms), or iv) a search space (e.g., search space zero) period unit.

[0380] The time-varying rule can be a random or deterministic method that allows the base station and the terminal to be synchronized. To set / determine the initial cyclic shift value for applying Method #3, the embodiments of Method #1 or Method #2 can be applied. That is, the initial cyclic shift value or cyclic shift offset value can be determined by Method #1 or Method #2. The determined cyclic shift value or cyclic shift offset value can be changed based on the time-varying unit of Method #3.

[0381] One or more of the above methods (methods #1 to #3) may be supported by network configuration. The base station may select one of the above methods and transmit a PDCCH based on the selected method. Before the terminal receives the PDCCH, the base station may configure / instruct the terminal to use the selected method based on broadcast signaling. After the terminal receives the broadcast signaling, the terminal may receive or calculate parameters necessary for implementing the selected method and receive the corresponding PDCCH.

[0382] The overall base station / terminal operation flow applying the above methods can be as follows.

[0383] The base station determines one of the above methods (Method #1 / Method #2 / Method #3).

[0384] The base station sets / instructs the above-determined method through broadcast signaling.

[0385] The base station transmits PDCCH through CORESET#0 based on the above-determined method.

[0386] The terminal determines one of the above methods based on the above broadcast signaling.

[0387] The terminal receives the PDCCH through CORESET#0 based on the above-determined method.

[0388] Afterwards, the terminal can perform operations such as receiving SIB1 and transmitting PRACH for random access.

[0389] The above-described methods can be used to protect PDCCH transmission / reception through CSS (common search space) where randomization through hashing function is not sufficiently applied. In this case, the cyclic shift value ( The parameter value) or cyclic shift offset value can be determined so that the first CCE index among the PDCCH CCEs can be transmitted without puncturing, if possible. This embodiment takes into consideration the following technical matters. Considering that the first CCE index of the received PDCCH is used when determining PUCCH transmission resources, the purpose is to minimize the terminal / base station implementation complexity without affecting the existing terminal operation.

[0390] In terms of implementation, the operations of the base station / terminal according to the embodiments described above (e.g., operations based on at least one of method #A, method #B, method #C, method #1, method #2, method #1, method #2, method #3) can be processed by the device of FIG. 16 described below (e.g., processor (110, 210) of FIG. 16).

[0391] In addition, the operations of the base station / terminal according to the above-described embodiment (e.g., operations based on at least one of method #A, method #B, method #C, method #1, method #2, method #1, method #2, method #3) may be stored in a memory (e.g., 140, 240 of FIG. 16) in the form of a command / program (e.g., instruction, executable code) for driving at least one processor (e.g., 110, 210 of FIG. 16).

[0392] The embodiments described below are specifically described with reference to FIGS. 14 and 15 in terms of terminal / base station operation. The methods described below are distinguished for convenience of explanation, and it is understood that some components of one method may be substituted for or combined with some components of another method.

[0393] FIG. 14 is a flowchart illustrating a method performed by a terminal according to one embodiment of the present specification.

[0394] Referring to FIG. 14, a method performed by a terminal according to one embodiment of the present specification includes an SS / PBCH block reception step (S1410) and a PDCCH reception step (S1420).

[0395] In S1410, the terminal receives a synchronization signal / physical broadcast channel block (Synchronization Signal / Physical Broadcast CHannel, SS / PBCH, block) from the base station.

[0396] For example, the SS / PBCH block may be a punctured SS / PBCH block based on at least one of the above-described embodiments. Specifically, a time-frequency structure (e.g., see FIGS. 8, 9, and 12) associated with the SS / PBCH block may be based on puncturing.

[0397] After the puncturing, the SS / PBCH block may be based on 12 resource blocks (RBs). The 12 resource blocks may be the remaining resource blocks excluding 8 resource blocks among 20 resource blocks based on the time-frequency structure of the existing SS / PBCH (e.g., FIG. 7). As a specific example, the 12 resource blocks may be the remaining resource blocks excluding subcarriers based on subcarrier numbers 0 to 47 and 192 to 239 among subcarriers based on subcarrier numbers 0 to 239 within 4 OFDM (Orthogonal Frequency Division Multiplexing) symbols.

[0398] The channel bandwidth associated with cell search based on the above SS / PBCH block may be less than 5 MHz. For example, the channel bandwidth may be 3 MHz.

[0399] In S1420, the terminal receives a physical downlink control channel (PDCCH) based on a control resource set (COntrol REsource SET, CORESET) from the base station.

[0400] For example, the CORESET may be CORESET#0 based on one of the embodiments described above.

[0401] In one embodiment, the CORESET may be obtained based on interleaved mapping, based on a frequency domain size of the CORESET determined based on a setting related to the CORESET being related to a channel bandwidth of less than 5 MHz. A shift value related to the interleaved mapping (e.g., ) can be determined based on a defined value. As a specific example, the shift value may be i) the defined value or ii) a cell ID (e.g., ) can be determined as a value obtained by adding the value defined above. The present embodiment can be based on at least one of Method #1 to Method #3. This will be described in detail below.

[0402] For example, the defined value may be set based on broadcast signaling. This embodiment may be based on Method #1. As a specific example, the defined value may be based on parameters additionally defined in a table related to the configuration of CORESET. Examples related to this will be described in more detail below.

[0403] Based on the broadcast signaling, the configuration related to the CORESET may be indicated. The configuration related to the CORESET may be one of the configurations defined in a table (e.g., Table for CORESET for Type0-PDCCH search space set). Each of the configurations may include i) the defined value, ii) the number of Resource Blocks (RBs) related to the frequency domain size (e.g., ), iii) number of symbols (e.g. ) and iv) may include offsets (e.g., offset(RBs)).

[0404] For example, the defined value may be determined based on puncturing related to the CORESET. The present embodiment may be based on method #2. The Resource Blocks (RBs) forming the CORESET may be obtained by puncturing one or more of the RBs based on the frequency domain size. The defined value may be a value based on a portion of the obtained RBs. Specific examples related to the puncturing are as follows.

[0405] The RBs based on the above frequency domain size can be 24 RBs (i.e., =24). The RBs forming the above CORESET may be 15 RBs obtained based on puncturing the 9 highest-numbered RBs (9 highest-numbered resource blocks) among the 24 RBs.

[0406] For example, the above-defined value may be a value that changes based on a time-varying unit. This embodiment may be based on method #3.

[0407] The initial value of the above defined value may be determined based on the embodiment of the above-described method #1 or method #2. Specifically, the initial value of the above defined value may be i) a value set based on broadcast signaling or ii) a value determined based on puncturing associated with the CORESET.

[0408] The above time-varying unit may be based on i) at least one slot or ii) a periodicity associated with a search space.

[0409] For example, the above setting related to the CORESET may be determined by controlResourceSetZero included in the PDCCH-ConfigSIB1 parameter in the MIB. The controlResourceSetZero indicates one of the indices defined in the Table (e.g., 0 to 15).

[0410] For example, the number of RBs based on the channel bandwidth of 3 MHz may be 15.

[0411] For example, the number of RBs related to the frequency domain size based on the settings related to the CORESET ( ) can be determined. The number of RBs can be 12 or 24.

[0412] In one embodiment, based on the number of RBs being 12, the CORESET may include 12 RBs. This embodiment may be based on method #1.

[0413] In one embodiment, based on the number of RBs being 24, the CORESET may include 15 RBs obtained based on puncturing 9 RBs out of the 24 RBs. This embodiment may be based on method #2.

[0414] The operations based on S1410 to S1420 described above can be implemented by the device of FIG. 16. For example, the terminal (200) can control one or more transceivers (230) and / or one or more memories (240) to perform the operations based on S1410 to S1420.

[0415] The embodiments described below are specifically described in terms of base station operation.

[0416] S1510 to S1520 described below correspond to S1410 to S1420 described in FIG. 14. Considering the above correspondence, redundant descriptions are omitted. That is, the specific description of the base station operation described below may be replaced with the description / example of FIG. 14 corresponding to the corresponding operation.

[0417] FIG. 15 is a flowchart illustrating a method performed by a base station according to another embodiment of the present specification.

[0418] Referring to FIG. 15, a method performed by a base station according to another embodiment of the present specification includes an SS / PBCH block transmission step (S1510) and a PDCCH transmission step (S1520).

[0419] In S1510, the base station transmits a synchronization signal / physical broadcast channel block (Synchronization Signal / Physical Broadcast CHannel, SS / PBCH, block) to the terminal.

[0420] In S1520, the base station transmits a physical downlink control channel (PDCCH) to the terminal based on a control resource set (COntrol REsource SET, CORESET).

[0421] In one embodiment, the CORESET may be obtained based on interleaved mapping, based on a frequency domain size of the CORESET determined based on a setting related to the CORESET being related to a channel bandwidth of less than 5 MHz. A shift value related to the interleaved mapping (e.g., ) can be determined based on defined values.

[0422] The operations based on S1510 to S1520 described above can be implemented by the device of FIG. 16. For example, the base station (100) can control one or more transceivers (130) and / or one or more memories (140) to perform the operations based on S1510 to S1520.

[0423] The operations / terms based on the embodiments described above have been described assuming a 5G system. However, this is for convenience of explanation and is not intended to limit the scope of application of the technical problems and problem-solving means to be solved by this specification to a specific system. That is, the technical problems / technical issues / problems mentioned in this specification may equally exist in other systems (e.g., 6G systems). It is self-evident that the embodiments of this specification can be expanded and applied to solve problems equally existing in the other systems. Therefore, for the expanded application of the embodiments of this specification to other systems, the terms defined / described based on the 5G system may be replaced / changed with terms defined in the other systems (or generalized terms not specific to one system). For example, PRACH, PUSCH, PUCCH, or SRS may be replaced / changed with uplink signals (or uplink channels) (e.g., first / second uplink signals). For example, SSB, CSI-RS, PDSCH, PDCCH can be replaced / changed with downlink signals (or downlink channels) (e.g., first / second downlink signals).

[0424] Hereinafter, a device to which an embodiment of the present specification can be applied (a device that implements a method / operation according to an embodiment of the present specification) is described with reference to FIG. 16.

[0425] FIG. 16 is a drawing showing the configuration of the first device and the second device according to an embodiment of the present specification.

[0426] The first device (100) may include a processor (110), an antenna unit (120), a transceiver (130), and a memory (140).

[0427] The processor (110) performs baseband-related signal processing and may include a higher layer processing unit (111) and a physical layer processing unit (115). The higher layer processing unit (111) may process operations of a MAC layer, an RRC layer, or higher layers. The physical layer processing unit (115) may process operations of a PHY layer. For example, when the first device (100) is a base station device in base station-terminal communication, the physical layer processing unit (115) may perform uplink reception signal processing, downlink transmission signal processing, etc. For example, when the first device (100) is a first terminal device in terminal-to-terminal communication, the physical layer processing unit (115) may perform downlink reception signal processing, uplink transmission signal processing, sidelink transmission signal processing, etc. In addition to performing baseband-related signal processing, the processor (110) may also control the overall operation of the first device (100).

[0428] The antenna unit (120) may include one or more physical antennas, and when it includes multiple antennas, it may support MIMO transmission and reception. The transceiver (130) may include an RF (Radio Frequency) transmitter and an RF receiver. The memory (140) may store information processed by the processor (110), and software, an operating system, applications, etc. related to the operation of the first device (100), and may also include components such as a buffer.

[0429] The processor (110) of the first device (100) may be configured to implement the operation of the base station in the base station-to-terminal communication (or the operation of the first terminal device in the terminal-to-terminal communication) in the embodiments described in the present disclosure.

[0430] The second device (200) may include a processor (210), an antenna unit (220), a transceiver (230), and a memory (240).

[0431] The processor (210) performs baseband-related signal processing and may include a higher layer processing unit (211) and a physical layer processing unit (215). The higher layer processing unit (211) may process operations of a MAC layer, an RRC layer, or higher layers. The physical layer processing unit (215) may process operations of a PHY layer. For example, when the second device (200) is a terminal device in base station-terminal communication, the physical layer processing unit (215) may perform downlink reception signal processing, uplink transmission signal processing, etc. For example, when the second device (200) is a second terminal device in terminal-to-terminal communication, the physical layer processing unit (215) may perform downlink reception signal processing, uplink transmission signal processing, sidelink reception signal processing, etc. In addition to performing baseband-related signal processing, the processor (210) may also control the overall operation of the second device (210).

[0432] The antenna unit (220) may include one or more physical antennas, and when it includes multiple antennas, it may support MIMO transmission and reception. The transceiver (230) may include an RF transmitter and an RF receiver. The memory (240) may store information processed by the processor (210), software, an operating system, applications, etc. related to the operation of the second device (200), and may also include components such as a buffer.

[0433] The processor (210) of the second device (200) may be configured to implement operations of the terminal in base station-to-terminal communication (or operations of the second terminal device in terminal-to-terminal communication) in the embodiments described in the present disclosure.

[0434] In the operation of the first device (100) and the second device (200), the same explanations given for the base station and the terminal (or the first terminal and the second terminal in the terminal-to-terminal communication) in the examples of the present disclosure may be applied, and redundant explanations are omitted.

[0435] Here, the wireless communication technology implemented in the device (100, 200) of the present disclosure may include not only LTE, NR, and 6G, but also Narrowband Internet of Things (NB-IoT) for low-power communication. For example, NB-IoT technology may be an example of LPWAN (Low Power Wide Area Network) technology, and may be implemented in standards such as LTE Cat NB1 and / or LTE Cat NB2, and is not limited to the above-described names.

[0436] Additionally or alternatively, the wireless communication technology implemented in the device (100, 200) of the present disclosure may perform communication based on LTE-M technology. For example, LTE-M technology may be an example of LPWAN technology and may be called by various names such as eMTC (enhanced Machine Type Communication). For example, LTE-M technology may be implemented by at least one of various standards such as 1) LTE CAT 0, 2) LTE Cat M1, 3) LTE Cat M2, 4) LTE non-BL (non-Bandwidth Limited), 5) LTE-MTC, 6) LTE Machine Type Communication, and / or 7) LTE M, and is not limited to the above-described names.

[0437] Additionally or alternatively, the wireless communication technology implemented in the device (100, 200) of the present disclosure may include at least one of ZigBee, Bluetooth, and Low Power Wide Area Network (LPWAN) that take low-power communication into account, and is not limited to the above-described names. For example, ZigBee technology can create personal area networks (PANs) related to small / low-power digital communication based on various standards such as IEEE 802.15.4, and may be called by various names.

Claims

1. In a method performed by a terminal, A step of receiving a Synchronization Signal / Physical Broadcast Channel (SS / PBCH, block); and A step of receiving a physical downlink control channel (PDCCH) based on a control resource set (COntrol REsource SET, CORESET); including: Based on the frequency domain size of the CORESET determined based on the settings related to the CORESET, the CORESET is obtained based on interleaved mapping, based on a channel bandwidth of less than 5 MHz, A method characterized in that the shift value associated with the interleaved mapping is determined based on a defined value.

2. In paragraph 1, A method characterized in that the above defined value is set based on broadcast signaling.

3. In paragraph 2, The above settings related to the CORESET are indicated based on the above broadcast signaling, The settings related to the above CORESET are one of the settings defined in the table, A method characterized in that each of the above settings comprises i) the defined value, ii) the number of resource blocks (RBs) related to the frequency domain size, iii) the number of symbols, and iv) an offset.

4. In paragraph 1, A method characterized in that the above defined value is determined based on puncturing associated with the CORESET.

5. In paragraph 4, The RBs (Resource Blocks, RBs) forming the above CORESET are obtained by puncturing one or more of the RBs based on the frequency domain size, A method characterized in that the above defined value is a value based on a portion of the above acquired RBs.

6. In paragraph 1, A method characterized in that the above defined value is a value that changes based on a time-varying unit.

7. In paragraph 6, A method characterized in that the initial value of the above defined value is i) a value set based on broadcast signaling or ii) a value determined based on puncturing associated with the CORESET.

8. In paragraph 6, A method characterized in that the above time-varying unit is based on i) at least one slot or ii) a periodicity associated with a search space.

9. In paragraph 1, A method characterized in that the above shift value is determined as i) the above defined value or ii) a value obtained by adding the above defined value to the cell ID.

10. In the terminal, One or more transmitters and receivers; one or more processors; and One or more memories connected to said one or more processors and storing instructions, A terminal characterized in that the instructions are set to cause the one or more processors to perform all steps of the method according to any one of claims 1 to 9, based on being executed by the one or more processors.

11. In a device comprising one or more memories and one or more processors functionally connected to the one or more memories, A device characterized in that said one or more memories store instructions that cause said one or more processors to perform all steps of a method according to any one of claims 1 to 9, based on being executed by said one or more processors.

12. In one or more non-transitory computer-readable media storing instructions, One or more non-transitory computer-readable media characterized in that the instructions executable by one or more processors cause the one or more processors to perform all steps of the method according to any one of claims 1 to 9.

13. In a method performed by a base station, A step of transmitting a Synchronization Signal / Physical Broadcast Channel (SS / PBCH, block); and A step of transmitting a physical downlink control channel (PDCCH) based on a control resource set (COntrol REsource SET, CORESET); including: Based on the frequency domain size of the CORESET determined based on the settings related to the CORESET, the CORESET is obtained based on interleaved mapping, based on a channel bandwidth of less than 5 MHz, A method characterized in that the shift value associated with the interleaved mapping is determined based on a defined value.

14. At the base station, One or more transmitters and receivers; one or more processors; and One or more memories connected to said one or more processors and storing instructions, A base station characterized in that the instructions are set to cause the one or more processors to perform all steps of the method according to claim 13, based on the instructions being executed by the one or more processors.

Images