Method for transmitting and receiving downlink control channel and apparatus thereof

Abstract

A method according to an embodiment of the present specification comprises the steps of: determining first CORESETs; and receiving a PDCCH on the basis of the first CORESETs. A time-frequency structure related to the first CORESETs is determined on the basis of replication of a time-frequency structure of a second CORESET related to a specific control resource set ID. The reception of the PDCCH is related to a first bandwidth, and the second CORESET is related to a second bandwidth smaller than the first bandwidth. CCE-to-REG mapping related to the PDCCH is characterized by being applied on the basis of rules related to the first CORESETs.

Description

Method and apparatus for transmitting and receiving a downlink control channel

[0001] This specification relates to a method and apparatus for transmitting and receiving a downlink control channel.

[0002] 5G NR is a successor technology to LTE (long term evolution) and is a new clean-slate type mobile communication system with characteristics such as high performance, low latency, and high availability. 5G NR can utilize all available spectrum resources, ranging from low frequency bands below 1 GHz to mid-frequency bands from 1 GHz to 10 GHz, and high frequency (millimeter wave) bands above 24 GHz.

[0003] The 6G (wireless communication) system aims for (i) very high data rates per device, (ii) a very large number of connected devices, (iii) global connectivity, (iv) very low latency, (v) reduced energy consumption of battery-free IoT (internet of things) devices, (vi) ultra-reliable connectivity, and (vii) connected intelligence with machine learning capabilities.

[0004] A scenario is being considered to support terminal types with various BW capabilities on the same carrier / band. For example, a method of supporting a WideBand (WB) carrier (e.g., 80 MHz) by dividing it into multiple NarrowBand (NB) bands (e.g., four 20 MHz bands) may be considered. In this case, the following problem arises. In addition to time-frequency settings for multiple narrow bands within a given frequency range (e.g., 80 MHz), additional time-frequency settings for wide bands (e.g., CORESET settings) are required.

[0005] In other words, even if the time-frequency structure of CORESET in a wide bandwidth (e.g., 80 MHz) and the time-frequency structure of CORESET in a narrow bandwidth (e.g., 20 MHz) are the same, additional signaling related to the time-frequency structure of CORESET in the wide bandwidth may need to be performed. As a specific example, for the same frequency band (e.g., X to X+80 MHz), in addition to the signaling of the settings related to the time-frequency structure of CORESET for the four narrow bandwidths, additional signaling of the settings related to the time-frequency structure of CORESET for the wide bandwidth must be performed.

[0006] The purpose of this specification is to propose a method for improving inefficiency in terms of signaling overhead in a configuration for supporting CORESET over a wide bandwidth.

[0007] The technical problems to be solved in this specification are not limited to those mentioned above, and other technical problems not mentioned will be clearly understood by those skilled in the art to which this specification belongs from the description below.

[0008] A method according to an embodiment of the present specification for solving the aforementioned problem comprises the steps of determining first control resource sets (CORESETs) and receiving a physical downlink control channel (PDCCH) based on the first CORESETs. The time-frequency structure associated with the first CORESETs is determined based on the replication of the time-frequency structure of a second CORESET associated with a specific control resource set ID. The reception of the PDCCH is associated with a first bandwidth, and the second CORESET is associated with a second bandwidth smaller than the first bandwidth. The CCE-to-REG mapping associated with the PDCCH is characterized by being applied based on rules associated with the first CORESETs. As described above, in PDCCH transmission and reception related to a first bandwidth larger than the second bandwidth, a separate time-frequency structure setting is not required.

[0009] According to the embodiments of this specification, no separate configuration is required for a time-frequency structure associated with a large bandwidth. Therefore, the signaling overhead required for configuration to support various bandwidths on the same carrier / band can be minimized.

[0010] In addition, the time-frequency structure is based on a specific CORESET associated with a small bandwidth, while CCE-to-REG mapping is performed based on separate rules. Therefore, PDCCH blocking can be mitigated. In other words, as scheduling of UEs with various BW capabilities is performed on the same carrier / band, the case where some UEs fail to be scheduled can be minimized.

[0011] The effects obtainable in this specification are not limited to those mentioned above, and other unmentioned effects will be clearly understood by those skilled in the art to which this specification belongs from the description below.

[0012] Figure 1 shows an example of a frame structure in an NR system.

[0013] Figure 2 shows an example of a resource grid in NR.

[0014] Figure 3 illustrates physical channels used in 3GPP systems and general signal transmission.

[0015] Figure 4 illustrates a single REG structure.

[0016] Figure 5 illustrates a non-interleaved CCE-REG mapping type.

[0017] Figure 6 illustrates an interleaved CCE-REG mapping type.

[0018] Figure 7 illustrates scheduling in the case where multi-cells are merged.

[0019] Figure 8 illustrates the HARQ-ACK process for DL ​​data.

[0020] Figure 9 illustrates the PUSCH transmission process.

[0021] FIG. 10 is a drawing illustrating a replication of a CORESET according to one embodiment of the present specification.

[0022] FIG. 11 is a flowchart for explaining a method performed by a terminal according to one embodiment of the present specification.

[0023] FIG. 12 is a flowchart illustrating a method performed by a base station according to another embodiment of the present specification.

[0024] FIG. 13 is a drawing showing the configuration of a first device and a second device according to an embodiment of the present specification.

[0025] In this specification, "A or B" may mean "only A," "only B," or "both A and B." Alternatively, in this specification, "A or B" may be interpreted as "A and / or B." For example, in this specification, "A, B or C" may mean "only A," "only B," "only C," or "any combination of A, B and C."

[0026] A slash ( / ) or a comma used in this specification may mean "and / or." For example, "A / B" may mean "A and / or B." Accordingly, "A / B" may mean "only A," "only B," or "both A and B." For example, "A, B, C" may mean "A, B or C."

[0027] In this specification, "at least one of A and B" may mean "only A," "only B," or "both A and B." Additionally, in this specification, the expressions "at least one of A or B" or "at least one of A and / or B" may be interpreted as synonymous with "at least one of A and B."

[0028] Additionally, in this specification, "at least one of A, B and C" may mean "only A," "only B," "only C," or "any combination of A, B and C." Also, "at least one of A, B or C" or "at least one of A, B and / or C" may mean "at least one of A, B and C."

[0029] Additionally, parentheses used in this specification may mean "for example." Specifically, when indicated as "control information (PDCCH)," "PDCCH" may be proposed as an example of "control information." In other words, "control information" in this specification is not limited to "PDCCH," and "PDCCH" may be proposed as an example of "control information." Furthermore, even when indicated as "control information (i.e., PDCCH)," "PDCCH" may be proposed as an example of "control information."

[0030] In the following explanation, 'when, if, in case of' can be replaced with 'based on'.

[0031] Technical features described individually within a single drawing in this specification may be implemented individually or simultaneously.

[0032] In this specification, a higher layer parameter may be a parameter that is set for the terminal, pre-set, or pre-defined. For example, a base station or a network may transmit the higher layer parameter to the terminal. For example, the higher layer parameter may be transmitted via radio resource control (RRC) signaling or medium access control (MAC) signaling.

[0033] In this specification, "set or defined" may be interpreted as being set or pre-configured to the device through pre-defined signaling (e.g., SIB, MAC, RRC) from a base station or network. In this specification, "set or defined" may be interpreted as being pre-configured to the device.

[0034] In this specification, user equipment (UE) may refer to portable devices, wireless devices, etc. In this specification, base station (BS) may refer to a radio access network (RAN) node, a transmission reception point (TRP), a network, an integrated access and backhaul (IAB) node, a portable device, a wireless device, etc.

[0035] The technology proposed in this specification can be used in various wireless communication systems such as CDMA (code division multiple access), FDMA (frequency division multiple access), TDMA (time division multiple access), OFDMA (orthogonal frequency division multiple access), and SC-FDMA (single carrier frequency division multiple access). CDMA can be implemented with wireless technologies such as UTRA (universal terrestrial radio access) or CDMA2000. TDMA can be implemented with wireless technologies such as GSM (global system for mobile communications) / GPRS (general packet radio service) / EDGE (enhanced data rates for GSM evolution). OFDMA can be implemented with wireless technologies such as IEEE (institute of electrical and electronics engineers) 802.11 (Wi-Fi), IEEE 802.16 (WiMAX), IEEE 802-20, E-UTRA (evolved UTRA), LTE (long term evolution), and 5G NR.

[0036] The technology proposed in this specification can be implemented as 6G wireless technology and applied to various 6G systems. For example, 6G systems may have key factors such as eMBB (enhanced mobile broadband), URLLC (ultra-reliable low latency communications), mMTC (massive machine-type communication), AI (artificial intelligence) integrated communication, tactile internet, high throughput, high network capacity, high energy efficiency, low backhaul and access network congestion, and enhanced data security.

[0037] In the following, the downlink (DL) refers to communication from a base station to a terminal, and the uplink (UL) refers to communication from a terminal to a base station. In the downlink, the transmitter may be part of the base station and the receiver may be part of the terminal. In the uplink, the transmitter may be part of the terminal and the receiver may be part of the base station. The base station may be referred to as the first communication device and the terminal as the second communication device. The base station (BS) may be replaced by terms such as fixed station, Node B, eNB (evolved-NodeB), gNB (Next Generation NodeB), BTS (base transceiver system), Access Point (AP), 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.

[0038] 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), and 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 part of the UMTS (Universal Mobile Telecommunications System). 3GPP (3rd Generation Partnership Project) LTE (Long Term Evolution) is part of E-UMTS (Evolved UMTS) using 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.

[0039] For clarity of explanation, the description is based on 3GPP communication systems (e.g., LTE-A, NR), but the technical scope of this specification is not limited thereto. LTE refers to technology from 3GPP TS 36.xxx Release 8 onwards. Specifically, LTE technology from 3GPP TS 36.xxx Release 10 onwards is referred to as LTE-A, and LTE technology from 3GPP TS 36.xxx Release 13 onwards is referred to as LTE-A pro. 3GPP NR refers to technology from TS 38.xxx Release 15 onwards. LTE / NR may be referred to as 3GPP systems. "xxx" indicates a specific standard document number. LTE / NR may be collectively referred to as 3GPP systems.

[0040] Regarding background technology, terms, abbreviations, etc. used in the description of this specification, reference may be made to matters described in standard documents published prior to this specification. For example, the following documents may be referenced.

[0041] 3GPP NR

[0042] - 3GPP TS 38.211: Physical channels and modulation

[0043] - 3GPP TS 38.212: Multiplexing and channel coding

[0044] - 3GPP TS 38.213: Physical layer procedures for control

[0045] - 3GPP TS 38.214: Physical layer procedures for data

[0046] - 3GPP TS 38.215: Physical layer measurements

[0047] - 3GPP TS 38.300: NR and NG-RAN Overall Description

[0048] - 3GPP TS 38.304: User Equipment (UE) procedures in idle mode and in RRC inactive state

[0049] - 3GPP TS 38.321: Medium Access Control (MAC) protocol

[0050] - 3GPP TS 38.322: Radio Link Control (RLC) protocol

[0051] - 3GPP TS 38.323: Packet Data Convergence Protocol (PDCP)

[0052] - 3GPP TS 38.331: Radio Resource Control (RRC) protocol

[0053] - 3GPP TS 37.324: Service Data Adaptation Protocol (SDAP)

[0054] - 3GPP TS 37.340: Multi-connectivity; Overall description

[0055] - 3GPP TS 23.287: Application layer support for V2X services; Functional architecture and information flows

[0056] - 3GPP TS 23.501: System Architecture for the 5G System

[0057] - 3GPP TS 23.502: Procedures for the 5G System

[0058] - 3GPP TS 23.503: Policy and Charging Control Framework for the 5G System; Stage 2

[0059] - 3GPP TS 24.501: Non-Access-Stratum (NAS) protocol for 5G System (5GS); Stage 3

[0060] - 3GPP TS 24.502: Access to the 3GPP 5G Core Network (5GCN) via non-3GPP access networks

[0061] - 3GPP TS 24.526: User Equipment (UE) policies for 5G System (5GS); Stage 3

[0062] As more communication devices require larger communication capacities, the need for enhanced mobile broadband communication compared to existing radio access technology is emerging. Furthermore, massive Machine Type Communications (MTC), which connects multiple devices and objects to provide various services anytime and anywhere, is also one of the major issues to be considered in next-generation communication. In addition, communication system designs that consider services and terminals sensitive to reliability and latency are being discussed. Accordingly, the introduction of next-generation radio access technology considering eMBB (enhanced mobile broadband communication), Mmtc (massive MTC), and URLLC (Ultra-Reliable and Low Latency Communication) is being discussed, and for convenience, this technology is referred to as NR in this specification. NR is an expression representing an example of 5G radio access technology (RAT).

[0063] A new RAT system including NR uses an OFDM transmission method or a similar transmission method. The new RAT system may follow OFDM parameters different from those of LTE. Alternatively, the new RAT system may follow the existing LTE / LTE-A numerology but have a larger system bandwidth (e.g., 100 MHz). Or, a single cell may support multiple numerologies. That is, terminals operating with different numerologies can coexist within a single cell.

[0064] Numerology corresponds to a single subcarrier spacing in the frequency domain. Different numerologies can be defined by scaling the reference subcarrier spacing to an integer N.

[0065] NR (New Rat) Numerology and Frame Structure

[0066] In an NR system, multiple numerologies can be supported. Here, a numerology can be defined by subcarrier spacing and CP (Cyclic Prefix) overhead. In this case, the multiple subcarrier spacings are the base subcarrier spacing as an integer N (or, It can be derived by scaling. In addition, 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.

[0067] In addition, various frame structures based on multiple numerologies can be supported in the NR system.

[0068] Below, we examine the OFDM (Orthogonal Frequency Division Multiplexing) numerology and frame structure that can be considered in an NR system.

[0069] Many OFDM numerologies supported by the NR system can be defined as shown in Table 1. The μ and circular prefix for the bandwidth part are obtained from the RRC parameters provided by the BS.

[0070]

[0071] NR supports multiple numerologies (or subcarrier spacing (SCS)) to support various 5G services. For example, when the SCS is 15 kHz, it supports a wide area in traditional cellular bands; when the SCS is 30 kHz / 60 kHz, it supports dense-urban, lower latency, and wider carrier bandwidth; and when the SCS is 60 kHz or higher, it supports a bandwidth greater than 24.25 GHz to overcome phase noise.

[0072] The NR frequency band is defined by two types of frequency ranges called FR1 and FR2. FR1 is the sub 6 GHz range, and FR2 is the above 6 GHz range, which can refer to millimeter wave (mmW).

[0073] Table 2 below illustrates the definition of the NR frequency band.

[0074]

[0075] Regarding the frame structure in an NR system, the size of various fields in the time domain is It is expressed as a multiple of the time unit of. Here, And, It is. Downlink and uplink transmission is It consists of radio frames having intervals. Here, each radio frame is It consists of 10 subframes having a period of . In this case, there may be one set of frames for the uplink and one set of frames for the downlink.

[0076] The transmission of uplink frame number i from a terminal (User Equipment, UE) is earlier than the start of the corresponding downlink frame at that terminal You must start beforehand.

[0077] Numerology Regarding this, slots within a subframe They are numbered in increasing order, and within the wireless frame They are numbered in increasing order. One slot is It consists of consecutive OFDM symbols, It is determined by the numerology and slot configuration used. Slot in a subframe The start is the OFDM symbol in the same subframe. It is aligned with the start of and time.

[0078] Not all terminals can transmit and receive simultaneously, which means that not all OFDM symbols in the downlink slot or uplink slot can be used.

[0079] Table 3 shows the number of OFDM symbols per slot in normal CP ( ), number of slots per wireless frame ( ), number of slots per subframe( Table 3 shows the number of OFDM symbols per slot, the number of slots per wireless frame, and the number of slots per subframe in the extended CP.

[0080]

[0081]

[0082] FIG. 1 illustrates an example of a frame structure in an NR system. FIG. 1 is for convenience of explanation only and is not intended to limit the scope of this specification.

[0083] In the case of Table 4, as an example where μ=2, i.e., the subcarrier spacing (SCS) is 60 kHz, referring to Table 3, one subframe (or frame) may include four slots, and the slots of one subframe={1,2,4} shown in Fig. 1 are examples, and the number of slot(s) that may be included in one subframe can be defined as in Table 3.

[0084] In addition, the mini-slot may consist of 2, 4, or 7 symbols, or more or fewer symbols.

[0085] Regarding physical resources in an NR system, antenna ports, resource grids, resource elements, resource blocks, and carrier parts may be considered.

[0086] Below, we will examine in detail the physical resources mentioned above that can be considered in an NR system.

[0087] Figure 2 shows an example of a supported resource grid in NR.

[0088] Referring to Fig. 2, for each subcarrier interval setting and carrier, N size,μ grid *N RB sc individual 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 not only between the uplink and downlink but also between the uplink and downlink.

[0089] Numerology One resource grid can be configured per antenna port p. Numerical Each element of the resource grid for and antenna port p is referred to as a resource element, and index pairs It is uniquely identified by. Here, is an index in the frequency domain, and refers to the location of a symbol within a subframe. When referring to resource elements in a slot, the index pair This is used. Here, am.

[0090] Numerology resource elements for and antenna port p is a complex value ...corresponds to. 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, and the resulting complex value is or This can be. In addition, the physical resource block is in the frequency domain It is defined by continuous subcarriers.

[0091] Considering that the UE may not be able to support the wide bandwidth to be supported in the NR system at once, the UE may be configured to operate in a portion of the cell's frequency bandwidth (hereinafter, bandwidth part, BWP).

[0092] 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.

[0093] Point A serves as a common reference point for the resource block grid and can be obtained as follows.

[0094] - offsetToPointA for the PCell downlink represents the frequency offset between point A and the lowest subcarrier of the lowest resource block that overlaps with the SS / PBCH block used by the UE for initial cell selection, and is expressed in resource block units assuming a 15kHz subcarrier interval for FR1 and a 60kHz subcarrier interval for FR2;

[0095] - absoluteFrequencyPointA represents the frequency-location of point A as expressed in ARFCN (absolute radio-frequency channel number).

[0096] Common resource blocks set subcarrier spacing In the frequency domain for , it is numbered from 0 upwards.

[0097] Subcarrier spacing setting The center of subcarrier 0 of common resource block 0 for coincides with 'point A'. Common resource block number in the frequency domain and subcarrier spacing settings The resource elements (k,l) for can be given as shown in Equation 1 below.

[0098]

[0099] Here, Is It can be defined relative to point A to correspond to a subcarrier centered at point A. Physical resource blocks within the bandwidth part (BWP) start from 0 Numbers are assigned up to, is the BWP number. Physical resource block in BWP i and common resource blocks The relationship between them can be given by the following mathematical formula 2.

[0100]

[0101] Here, can be a common resource block that starts relative to common resource block 0.

[0102] A slot contains multiple symbols in the time domain. For example, in the case of a standard CP, one slot contains 14 symbols, and in the case of an extended CP, one slot contains 12 symbols. A carrier contains multiple subcarriers in the frequency domain. A Resource Block (RB) is defined as multiple (e.g., 12) consecutive subcarriers in the frequency domain. Multiple RB interlacs (simply interlacs) can be defined in the frequency domain. An interlac m∈{0, 1, ..., M-1} can be composed of (common) RBs {m, M+m, 2M+m, 3M+m, ...}. M represents the number of interlacs. A Bandwidth Part (BWP) is defined as multiple consecutive RBs (e.g., physical RB, PRB) in the frequency domain and can correspond to a single OFDM numerology (e.g., SCS(u), CP length, etc.). A carrier wave may contain up to N (e.g., 5) BWPs. Data communication is performed through the active BWPs, and only one BWP can be active for a single terminal within a single cell / carrier wave. In the resource grid, each element is referred to as a Resource Element (RE), and one modulation symbol can be mapped to it.

[0103] Physical channels and general signal transmission

[0104] Figure 3 illustrates physical channels used in a 3GPP system and general signal transmission. In a wireless communication system, a terminal receives information from a base station via a downlink (DL) and transmits information to the base station via an uplink (UL). The information transmitted and received by 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.

[0105] When the 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 do this, 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. After that, the terminal receives a Physical Broadcast Channel (PBCH) from the base station to obtain broadcast information within the cell. Meanwhile, during the initial cell search phase, the terminal receives a Downlink Reference Signal (DL RS) to check the downlink channel status.

[0106] 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 the information carried on the PDCCH (S302).

[0107] Meanwhile, when connecting to a base station for the first time or when there are no wireless resources available for signal transmission, the terminal may perform a Random Access Procedure (RACH) with respect to the base station (S303 to S306). To this end, the terminal transmits a specific sequence as a preamble through a Physical Random Access Channel (PRACH) (S303 and S305), and may receive a response message (RAR (Random Access Response) message) for the preamble through a PDCCH and a corresponding PDSCH. In the case of a contention-based RACH, a Contention Resolution Procedure may additionally be performed (S306).

[0108] A terminal that has performed the procedure described above may subsequently 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 may receive Downlink Control Information (DCI) through the PDCCH.

[0109] The UE monitors a set of PDCCH candidates at monitoring occasions configured in one or more control element sets (CORESETs) on the 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 the search space sets, and the search space sets may be common search space sets or UE-specific search space sets. A CORESET consists of a set of (physical) resource blocks having durations of 1 to 3 OFDM symbols. The network may be configured so that the UE has multiple CORESETs. The UE monitors PDCCH candidates within one or more search space sets. Here, monitoring means attempting to decode the PDCCH candidate(s) within the search space. If the UE succeeds in decoding one of the PDCCH candidates within the search space, the UE determines that it has detected a PDCCH in that candidate and performs PDSCH reception or PUSCH transmission based on the DCI within the detected PDCCH.

[0110] PDCCH can be used to schedule DL transmissions on PDSCH and UL transmissions on PUSCH. Here, the DCI on PDCCH includes a downlink assignment (i.e., a DL grant) that includes at least modulation and coding formats and resource allocation information associated with a downlink shared channel, or an uplink grant that includes modulation and coding formats and resource allocation information associated with an uplink shared channel. The format of the DCI varies depending on its intended use.

[0111] Meanwhile, control information transmitted by the terminal to the base station via the uplink or received by the terminal 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 control information such as the above-mentioned CQI / PMI / RI via PUSCH and / or PUCCH.

[0112] Downlink (DL) physical channel / signal

[0113] (1) PDSCH

[0114] The PDSCH carries downlink data (e.g., DL-shared channel transport block, DL-SCH TB). The TB is encoded into a CodeWord (CW), then transmitted after undergoing processes such as scrambling and modulation. A CW contains one or more Code Blocks (CBs). One or more CBs can be grouped into a single CBG (CB group). Depending on the cell configuration, the PDSCH can carry up to two CWs. Scrambling and modulation are performed for each CW, and the modulation symbols generated from each CW are mapped to one or more layers. Each layer undergoes precoding, is mapped to a resource along with the DMRS, and is transmitted through the corresponding antenna port. PDSCH can be dynamically scheduled by PDCCH or semi-statically scheduled based on upper-layer (e.g., RRC) signaling (and / or Layer 1 (L1) signaling (e.g., PDCCH)) (Configured Scheduling, CS). Therefore, in dynamic scheduling, PDCCH is involved with PDSCH transmissions, whereas in CS, PDCCH is not involved with PDSCH transmissions. CS includes semi-persistent scheduling (SPS).

[0115] (2) PDCCH

[0116] The PDCCH carries Downlink Control Information (DCI). For example, the PCCCH (i.e., DCI) carries the transmission format and resource allocation of the DL-SCH, frequency / time resource allocation information for the UL-SCH (shared channel), paging information for the PCH (paging channel), system information on the DL-SCH, frequency / time resource allocation information for higher-layer control messages such as Random Access Responses (RAR) transmitted on the PDSCH, transmission power control commands, and information regarding the activation / deactivation of SPS / CS (Configured Scheduling). Various DCI formats are provided depending on the information within the DCI.

[0117] Table 5 shows examples of DCI formats transmitted via PDCCH.

[0118]

[0119] DCI format 0_0 is used to schedule TB-based (or TB-level) PUSCH, and DCI format 0_1 ​​may be used to schedule TB-based (or TB-level) PUSCH or CBG (Code Block Group)-based (or CBG-level) PUSCH. DCI format 1_0 is used to schedule TB-based (or TB-level) PDSCH, and DCI format 1_1 may be used to schedule TB-based (or TB-level) PDSCH or CBG-based (or CBG-level) PDSCH (DL grant DCI). DCI format 0_0 / 0_1 is referred to as UL grant DCI or UL scheduling information, and DCI format 1_0 / 1_1 may be referred to as DL grant DCI or UL scheduling information. DCI format 2_0 is used to transmit dynamic slot format information (e.g., dynamic SFI) to terminals, and DCI format 2_1 is used to transmit downlink pre-Emption information to terminals. DCI format 2_0 and / or DCI format 2_1 may be transmitted to terminals within a group through a group common PDCCH, which is a PDCCH transmitted to terminals defined as a group.

[0120] PDCCH / DCI includes a cyclic redundancy check (CRC), and the CRC is masked / scrambled with various identifiers (e.g., Radio Network Temporary Identifier, RNTI) depending on the owner or use of the PDCCH. For example, if the PDCCH is for a specific terminal, the CRC is masked with C-RNTI (Cell-RNTI). If the PDCCH is for paging, the CRC is masked with P-RNTI (Paging-RNTI). If the PDCCH is for system information (e.g., System Information Block, SIB), the CRC is masked with SI-RNTI (System Information RNTI). If the PDCCH is for random access acknowledgments, the CRC is masked with RA-RNTI (Random Access-RNTI).

[0121] Table 6 illustrates the uses and transmission channels of the PDCCH according to RNTI. The transmission channel represents the transmission channel associated with the data carried by the PDSCH / PUSCH scheduled by the PDCCH.

[0122]

[0123] The modulation scheme of the PDCCH is fixed (e.g., Quadrature Phase Shift Keying, QPSK), and a single PDCCH consists of 1, 2, 4, 8, or 16 Control Channel Elements (CCEs) depending on the Aggregation Level (AL). A single CCE consists of 6 Resource Element Groups (REGs). A single REG is defined by one OFDMA symbol and one (P)RB.

[0124] FIG. 4 illustrates a REG structure. In FIG. 4, D represents a resource element (RE) to which DCI is mapped, and R represents an RE to which DMRS is mapped. DMRS is mapped to the 1st, 5th, and 9th REs in the frequency domain direction within a single symbol.

[0125] PDCCH is transmitted via CORESET (Control Resource Set). CORESET corresponds to a set of physical resources / parameters used to carry PDCCH / DCI within a BWP. For example, CORESET includes a set of REGs with a given neuromonology (e.g., SCS, CP length, etc.). CORESET can be configured via system information (e.g., MIB) or terminal-specific (UE-specific) upper-layer signaling (e.g., RRC). Examples of parameters / information used to configure CORESET are as follows. One or more CORESETs are configured for a single terminal, and multiple CORESETs may overlap in the time / frequency domain.

[0126] - controlResourceSetId: Represents the identification information (ID) of the CORESET.

[0127] - frequencyDomainResources: Represents the frequency domain resources of the CORESET. It is indicated by a bitmap, where each bit corresponds to an RB group (= 6 consecutive RBs). For example, the MSB (Most Significant Bit) of the bitmap corresponds to the first RB group within the BWP. The RB group corresponding to the bit with a value of 1 is allocated as the frequency domain resource of the CORESET.

[0128] - duration: Represents the time domain resource of the CORESET. It indicates the number of consecutive OFDMA symbols that make up the CORESET. For example, duration has a value of 1 to 3.

[0129] - cce-REG-MappingType: Indicates the CCE-to-REG mapping type. Interleaved and non-interleaved types are supported.

[0130] - precoderGranularity: Represents the precoder granularity in the frequency domain.

[0131] - tci-StatesPDCCH: Represents information (e.g., TCI-StateID) indicating the Transmission Configuration Indication (TCI) state for the PDCCH. The TCI state is used to provide the Quasi-Co-Location (QCL) relationship between the DL RS(s) within the RS set (TCI-state) and the PDCCH DMRS port.

[0132] - tci-PresentInDCI: Indicates whether the TCI field within the DCI is included.

[0133] - pdcch-DMRS-ScramblingID: Represents the information used to initialize the PDCCH DMRS scrambling sequence.

[0134] REGs within a CORESET are numbered based on a time-first mapping manner. That is, REGs are numbered sequentially starting from 0, beginning with the first OFDM symbol in the lowest-numbered resource block within the CORESET.

[0135] The mapping type from CCE to REG is set to one of the following: a non-interleaved CCE-REG mapping type or an interleaved CCE-REG mapping type.

[0136] Figure 5 illustrates a non-interleaved CCE-REG mapping type.

[0137] - Non-interleaved CCE-REG mapping type (or localized mapping type): The 6 REGs for a given CCE form a single REG bundle, and all REGs for a given CCE are consecutive. One REG bundle corresponds to one CCE.

[0138] Figure 6 illustrates an interleaved CCE-REG mapping type.

[0139] - Interleaved CCE-REG mapping type (or Distributed mapping type): 2, 3, or 6 REGs for a given CCE form a single REG bundle, and the REG bundle is interleaved within the CORESET. A REG bundle within the CORESET consisting of 1 OFDM symbol or 2 OFDM symbols consists of 2 or 6 REGs, and a REG bundle within the CORESET consisting of 3 OFDM symbols consists of 3 or 6 REGs. The size of the REG bundle is set per CORESET.

[0140] To receive a PDCCH, the terminal may monitor a set of PDCCH candidates in a CORESET (e.g., blind decoding). A PDCCH candidate represents a CCE(s) that the terminal monitors for receiving / detecting a PDCCH. PDCCH monitoring may be performed on one or more CORESETs on active DL BWPs on each active cell where PDCCH monitoring is configured. The set of PDCCH candidates monitored by the terminal is defined as a set of PDCCH Search Spaces (SS). The SS set may be a set of Common Search Spaces (CSS) or a set of UE-specific Search Spaces (USS).

[0141] Table 7 illustrates the PDCCH search space.

[0142]

[0143] SS sets can be configured via system information (e.g., MIB) or terminal-specific (UE-specific) upper layer (e.g., RRC) signaling. Each DL BWP in a serving cell may have up to S (e.g., 10) SS sets configured. For example, the following parameters / information may be provided for each SS set. Each SS set is associated with one CORESET, and each CORESET configuration may be associated with one or more SS sets.

[0144] - searchSpaceId: Represents the ID of the SS set.

[0145] - controlResourceSetId: Represents the CORESET associated with the SS set.

[0146] - monitoringSlotPeriodicityAndOffset: Represents the PDCCH monitoring period interval (in slots) and the PDCCH monitoring interval offset (in slots).

[0147] - monitoringSymbolsWithinSlot: Represents the first OFDMA symbol(s) for PDCCH monitoring within the slot where PDCCH monitoring is configured. It is indicated by a bitmap, where each bit corresponds to each OFDMA symbol within the slot. The MSB of the bitmap corresponds to the first OFDMA symbol within the slot. The OFDMA symbol(s) corresponding to bit(s) with a bit value of 1 correspond to the first symbol(s) of the CORESET within the slot.

[0148] - nrofCandidates: AL={1, 2, 4, 8, 16} represents the number of star PDCCH candidates (e.g., one of 0, 1, 2, 3, 4, 5, 6, 8).

[0149] - searchSpaceType: Indicates whether the SS type is CSS or USS.

[0150] - DCI Format: Indicates the DCI format of the PDCCH candidate.

[0151] Based on the CORESET / SS set configuration, the terminal can monitor PDCCH candidates from one or more SS sets within the slot. An occasion (e.g., time / frequency resources) when PDCCH candidates must be monitored is defined as a PDCCH (monitoring) opportunity. One or more PDCCH (monitoring) opportunities may be configured within the slot.

[0152] Carrier Aggregation (CA)

[0153] NR can support wider uplink and downlink bandwidths by merging multiple uplink and downlink carriers (i.e., carrier merging). Through carrier merging, it is possible to transmit and receive signals on multiple carriers. When carrier merging is applied, each carrier can be referred to as a component carrier (CC). CCs can be adjacent or non-adjacent to each other in the frequency domain. The bandwidth of each CC can be determined independently. Asymmetric carrier merging is also possible, where the number of UL CCs and DL CCs differs. In NR, radio resources are classified and managed as cells, and a cell can consist of one DL CC and zero to two UL CCs. For example, a cell can consist of (i) only one DL CC, (ii) one DC CC and one UL CC, or (ii) one DL CC and two UL CCs (including one supplementary UL CC). Cells are classified as follows. In this specification, the term "cell" may be interpreted according to the context and may mean, for example, a serving cell. Additionally, unless otherwise stated, the operations of this specification may apply to each serving cell.

[0154] - PCell (Primary Cell): In the case of a terminal with carrier aggregation enabled, a cell operating on the primary frequency (e.g., Primary Component Carrier, PCC) where the terminal performs the initial connection establishment procedure or initiates the re-establishment procedure. In the case of DC (Dual Connectivity), an MCG (Master Cell Group) cell operating on the primary frequency where the terminal performs the initial connection establishment procedure or initiates the re-establishment procedure.

[0155] - SCell (Secondary Cell): For terminals with carrier aggregation enabled, a cell that provides additional wireless resources besides the special cell.

[0156] - PSCell (Primary SCG Cell): In the case of a DC, the SCG (Secondary Cell Group) cell where the terminal performs random access during the RRC reconfiguration and synchronization process.

[0157] - Special Cell (SpCell): In the case of DC, the special cell represents the PCell of the MCG or the PSCell of the SCG. Otherwise (i.e., non-DC), the special cell represents the PCell.

[0158] - Serving Cell (ServCell): Represents a cell configured for a terminal in the RRC_CONNECTED state. If CA / DA is not configured, only one serving cell (i.e., PCell) exists. If CA / DA is configured, the serving cell represents a set of cells including special cell(s) and all SCells.

[0159] Meanwhile, control information may be configured to be transmitted and received only through specific cells. For example, UCI may be transmitted only through special cells (e.g., PCell). If a SCell where PUCCH transmission is allowed (hereinafter referred to as PUCCH-SCell) is configured, UCI may also be transmitted through the PUCCH-SCell. As another example, the base station may allocate a scheduling cell (set) to reduce the complexity of PDCCH BD (blinding decoding) at the terminal side. For PDSCH reception / PUSCH transmission, the terminal may perform PDCCH detection / decoding only in the scheduling cell. Additionally, the base station may transmit PDCCH only through the scheduling cell (set). For example, a PDCCH for downlink allocation may be transmitted from cell #0 (i.e., the scheduling cell), and the corresponding PDSCH may be transmitted from cell #2 (i.e., the scheduled cell) (Cross-Carrier Scheduling, CCS). Scheduling cells (sets) can be configured in a terminal-specific, terminal-group-specific, or cell-specific manner. Scheduling cells include special cells (e.g., PCell).

[0160] For CCS, the CIF (carrier indicator field) is used. The CIF is semi-static and can be disabled / enabled by terminal-specific (or terminal group-specific) upper-layer (e.g., Radio Resource Control, RRC) signaling. The CIF field is an x-bit field (e.g., x=3) within the PDCCH (i.e., DCI) and can be used to indicate the (serving) cell index of a scheduled cell.

[0161] - CIF Disabled: CIF is absent within the PDCCH. The PDCCH on the scheduling cell allocates PDSCH / PUSCH resources on the same cell. In other words, the scheduling cell is identical to the scheduled cell.

[0162] - CIF Enabled: A CIF exists within the PDCCH. The PDCCH in scheduling can use the CIF to allocate PDSCH / PUSCH resources on one of multiple cells. The scheduling cell may be the same as or different from the scheduled cell. PDSCH / PUSCH refers to PDSCH or PUSCH.

[0163] Figure 7 illustrates scheduling in the case where multi-cells are merged.

[0164] Referring to Fig. 7, assume that three cells have been merged. When CIF is disabled, each cell can only transmit the PDCCH that schedules its own PDSCH / PUSCH (self-carrier scheduling, SCS). On the other hand, when CIF is enabled by terminal-specific (or terminal-group-specific or cell-specific) upper-layer signaling and Cell A is set as the scheduling cell, Cell A can transmit not only the PDCCH that schedules Cell A's PDSCH / PUSCH but also the PDCCH that schedules the PDSCH / PUSCH of other cells (i.e., scheduled cells) (cross-carrier scheduling, CCS). In this case, Cells B / C do not transmit the PDCCH that schedules their own cells.

[0165] Data transmission and HARQ-ACK process

[0166] Figure 8 illustrates the HARQ-ACK process for DL ​​data.

[0167] Referring to FIG. 8, the terminal can detect PDCCH in slot #n. Here, PDCCH includes downlink scheduling information (e.g., DCI format 1_0, 1_1), and PDCCH represents the DL assignment-to-PDSCH offset (K0) and the PDSCH-HARQ-ACK reporting offset (K1). For example, DCI format 1_0, 1_1 may include the following information.

[0168] - Frequency domain resource assignment: Represents the set of RBs assigned to PDSCH

[0169] - Time domain resource assignment: K0 indicates the starting position (e.g., OFDM symbol index) and length (e.g., number of OFDM symbols) of the PDSCH within the slot.

[0170] - PDSCH-to-HARQ_feedback timing indicator: Indicates K1

[0171] - HARQ process number (4 bits): Represents the HARQ process ID (Identity) for data (e.g., PDSCH, TB)

[0172] - PUCCH resource indicator (PRI): Indicates the PUCCH resource to be used for UCI transmission among multiple PUCCH resources within the PUCCH resource set.

[0173] Subsequently, the terminal may receive a PDSCH at slot #(n+K0) according to the scheduling information of slot #n, and then transmit a UCI via a PUCCH at slot #(n+K1). Here, the UCI includes a HARQ-ACK response for the PDSCH. If the PDSCH is configured to transmit up to 1 TB, the HARQ-ACK response may consist of 1 bit. If the PDSCH is configured to transmit up to 2 TB, the HARQ-ACK response may consist of 2 bits if spatial bundling is not configured, and 1 bit if spatial bundling is configured. If the time for transmitting HARQ-ACKs for multiple PDSCHs is designated as slot #(n+K1), the UCI transmitted at slot #(n+K1) includes HARQ-ACK responses for multiple PDSCHs.

[0174] Figure 9 illustrates the PUSCH transmission process.

[0175] Referring to FIG. 9, the terminal can detect PDCCH in slot #n. Here, PDCCH includes uplink scheduling information (e.g., DCI format 0_0, 0_1). DCI format 0_0, 0_1 may include the following information.

[0176] - Frequency domain resource assignment: Indicates the set of RBs assigned to PUSCH

[0177] - Time domain resource assignment: Indicates slot offset K2, the starting position (e.g., symbol index) and length (e.g., number of OFDM symbols) of PUSCH within the slot. The starting symbol and length may be indicated via SLIV (Start and Length Indicator Value) or individually.

[0178] Subsequently, the terminal can transmit PUSCH at slot #(n+K2) according to the scheduling information of slot #n. Here, PUSCH includes UL-SCH TB. If the time of transmission of PUCCH overlaps with the time of transmission of PUSCH, UCI can be transmitted via PUSCH (PUSCH piggyback).

[0179] The contents examined above may be applied in combination with the methods proposed in this specification described below, or may be supplemented to clarify the technical features of the methods proposed in this specification. The methods described below are distinguished merely for the convenience of explanation, and it goes without saying that parts of any one method may be substituted with parts of another method or combined with one another.

[0180] For example, technical terms used in this disclosure may be as follows.

[0181] - SSB: Synchronization Signal Block

[0182] - MIB: Master Information Block

[0183] - RMSI: Remaining Minimum System Information

[0184] - FR1: Frequency Range 1. Refers to the frequency range of 6 GHz or lower (e.g., 450 MHz ~ 6000 MHz).

[0185] - FR2: Frequency Range 2. Refers to the millimeter wave (mmWave) region above 24 GHz (e.g., 24,250 MHz ~ 52,600 MHz).

[0186] - BW: Bandwidth

[0187] - BWP: Bandwidth Part

[0188] - RNTI: Radio Network Temporary Identifier

[0189] - SI-RNTI: System Information Radio-Network Temporary Identifier

[0190] - P-RNTI: Paging RNTI

[0191] - RAR-RNTI: Random Access Response RNTI

[0192] - TC-RNTI: Temporary C-RNTI

[0193] - C-RNTI: Cell RNTI

[0194] - CRC: Cyclic Redundancy Check

[0195] - SIB: System Information Block

[0196] - SIB1: SIB1 for NR devices (i.e., Remaining Minimum System Information (RMSI)). Broadcasts information necessary for cell connection of NR terminals.

[0197] - DCI: Downlink Control Information

[0198] - PDCCH: Physical Downlink Control CHannel

[0199] - PUCCH: Physical Uplink Control CHannel

[0200] - PDSCH: Physical Downlink Shared CHannel

[0201] - PUSCH: Physical Uplink Shared CHannel

[0202] - SS: Search Space

[0203] - SSS: Search Space Set

[0204] - CORESET: Control Resource Set. The time / frequency resource when the NR terminal attempts candidate PDCCH decoding.

[0205] - CORESET#0: CORESET for Type0-PDCCH CSS set for NR devices (configured in MIB)

[0206] - 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

[0207] - MO: PDCCH Monitoring Occasion

[0208] - Cell defining SSB (CD-SSB): An NR SSB that includes RMSI scheduling information

[0209] - Non-cell defining SSB (non-CD-SSB): Refers to an SSB deployed in an NR sync raster that does not include the corresponding cell's RMSI scheduling information for measurement purposes. However, it may include information indicating the location of the cell defining SSB.

[0210] - SCS: subcarrier spacing

[0211] - 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.

[0212] - TB: Transport Block

[0213] - SIB1-PDSCH: PDSCH transmitting SIB1

[0214] - SIB1-DCI: DCI scheduling SIB1-PDSCH. DCI format 1_0 with CRC scrambled by SI-RNTI.

[0215] - SIB1-PDCCH: PDCCH transmitting SIB1-DCI

[0216] - MCS: Modulation and Coding Scheme

[0217] - FDRA: Frequency Domain Resource Allocation

[0218] - TDRA: Time Domain Resource Allocation

[0219] - RA: Random Access

[0220] - MSGA: preamble and payload transmissions of the random access procedure for 2-step RA type.

[0221] - 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.

[0222] - RO: 4-step RACH and 2-step RACH(if configured)를 위한 RO(RACH Occasion)

[0223] - PG: MsgA-Preambles Group

[0224] - RAR: Randoma Access Response

[0225] - RAR window: the time window to monitor RA response(s)

[0226] - FH: Frequency Hopping

[0227] - DL: Downlink

[0228] - UL: Uplink

[0229] - iBWP: initial BWP

[0230] - iBWP-DL(-UL): initial DL(UL) BWP

[0231] - CS: Cyclic shift

[0232] - NB: Narrowband

[0233] - WB: Wideband

[0234] - TO: Traffic Offloading

[0235] - mMTC; massive Machine Type Communications

[0236] - eMBB: enhanced Mobile Broadband Communication

[0237] - URLLC: Ultra-Reliable and Low Latency Communication

[0238] - FDD: Frequency Division Duplex

[0239] - HD-FDD: Half-Duplex-FDD

[0240] - DRX: Discontinuous Reception

[0241] - MAC (CE): Medium Access Control (Control Element)

[0242] - MAC CE

[0243] - RRC: Radio Resource Control

[0244] - RRM: Radio Resource Management

[0245] - MM: Mobility Management

[0246] - IWSN: Industrial Wireless Sensor Network

[0247] - LPWA: Low Power Wide Area

[0248] - RB: Resource Block

[0249] - CCE: Control Channel Element

[0250] - AL: Aggregation Level

[0251] - PRG: Physical Resource-block Group

[0252] - DFT-s-OFDM: DFT-spread OFDM

[0253] - PBCH: Physical Broadcast Channel

[0254] - BD: blind detection

[0255] - EPRE: Energy Per RE

[0256] - SNR: Signal-to-Noise Ratio

[0257] - TDM: Time Division Multiplexing

[0258] - FDM: Frequency Division Multiplexing

[0259] - DMRS: DeModulation Reference Signal

[0260] - TDD: Time Division Duplex

[0261] - PCI: Physical layer Cell ID

[0262] - UE: User Equipment. In the case of LTE, NR, or next-generation communication systems, it refers to the LTE, NR, or next-generation communication system UE / terminal, respectively.

[0263] - F-gap: Frequency gap

[0264] - T-gap: Time gap

[0265] - TD: Time Domain

[0266] - FD: Frequency Domain

[0267] - PEI: Paging Early Indication

[0268] - LP-WUS: Low-Power Wake-Up Signal

[0269] - LP-SS: Low-Power Synchronization Signal

[0270] - RSRP: Reference Signal Received Power

[0271] - PRB: Physical Resource Block

[0272] - VRB: Virtual Resource Block

[0273] - PHR: Power Headroom Report

[0274] - BPF: Band-Pass Filter

[0275] - SFO: Sampling Frequency Offset

[0276] - ASK: Amplitude Shift Keying

[0277] - DSB-ASK: Double-SideBand ASK

[0278] - SSB-ASK: Single-SideBand ASK

[0279] - PR-ASK: Phase-Reversal ASK

[0280] - OOK: On-Off Keying

[0281] - PSK: Phase-Shift Keying

[0282] - BPSK: Binary-PSK

[0283] - FSK: Frequency-Shift Keying

[0284] - B-FSK: Binary FSK

[0285] - M-FSK: M-ary FSK

[0286] - Ncp-ofdm, Ncp, Nu: Sample unit lengths of the CP-OFDM symbol segment, CP segment, and useful OFDM symbol segment, respectively, in the CP-OFDM symbol. Ncp-ofdm = Ncp + Nu

[0287] - ME: Manchester Encoding

[0288] - OH: Overhead

[0289] - HARQ: Hybrid Automatic Repeat Request

[0290] - DAI: Downlink Assignment Index

[0291] - RV: Redundancy Version

[0292] - NDI: New Data Indicator

[0293] - PRI: PUCCH Resource Indicator

[0294] - XR: eXtended Reality

[0295] - SR: Scheduling Request

[0296] - A / N: Ack / Nack

[0297] - NES: Network Energy Saving

[0298] - Floor(X): A floor function that takes a real number X as input and outputs the greatest integer less than or equal to X.

[0299] - Ceil(X): A ceiling function that takes a real number X as input and outputs the smallest integer greater than or equal to X.

[0300] In order to support terminal types with various BW capabilities on the same carrier / band in a next-generation communication system, it is possible to support a situation where a WB UE and an NB (e.g., 20 MHz) UE are simultaneously connected / operating on a single WB (e.g., 80 MHz) carrier. In this case, the WB (e.g., 80 MHz) carrier can be divided into multiple (e.g., 4) NB (e.g., 20 MHz) bands, and the NB UEs can be distributed among the NBs within the WB carrier (according to UE ID, etc.).

[0301] In the above-described scenario, the present specification relates to a method of setting up NB CORESET#0s having the same time / frequency structure in the form of so-called replicas for each NB, and transmitting a PDCCH for a WB UE through the NB CORESET#0 replicas.

[0302] The proposals of this specification can be equally applied to setting up and operating CORESET#0s in the form of replicas on each fragmented carrier when fragmented carriers are viewed as a single cell (or as individual cells). Furthermore, although the proposals of this specification are described below with examples of CORESET#0, the proposals of this specification can be equally applied to other CORESETs (i.e., CORESET#n (n≠0)).

[0303] In this specification, when NB CORESET#0 is replicated within a WB, the NB CORESET#0 is referred to as the original CORESET#0. Additionally, in cases where the application of the proposals in this specification is not limited to a WB CORESET#0 configuration in the form of a replica, the term "replica" in NB CORESET#0 replica may be interpreted / applied with omission.

[0304] The proposals / embodiments of this specification are not limited to cases where the small bandwidth is NB. Specifically, the proposals / embodiments of this specification are not limited by the size of the bandwidth and can be applied to all cases where a relatively narrow band and a wide band are simultaneously set / operated. For example, NB CORESET#0 can be interpreted / applied as CORESET#0. For example, NB terminal / WB terminal can be interpreted / replaced as a first terminal / second terminal (or second terminal / first terminal). For example, an NB terminal supporting NB (e.g., a terminal supporting only NB) can be interpreted / replaced as a terminal supporting a first bandwidth (or a second bandwidth), and a WB terminal supporting WB (e.g., a terminal supporting both NB and WB) can be interpreted / replaced as a terminal supporting a second bandwidth (or a first bandwidth) which is larger than the first bandwidth (or a second bandwidth).

[0305] [How to configure / set up NB CORESET#0 replica within WB]

[0306] According to the present embodiment, NB CORESET#0 is configured within a specific NB (which serves as a reference) for PDCCH transmission for an NB terminal. For PDCCH transmission for a WB terminal, WB CORESET#0 can be configured / set by replicating the NB CORESET#0 into the frequency domain of other NB(s). Consequently, WB CORESET#0 can be configured by replicating NB CORESET#0s having the same time / frequency structure to all NBs involved in the configuration of WB CORESET#0.

[0307] NB CORESET#0 replica(s) can be generated by applying a frequency offset (F-offset) based on the time / frequency position of the specific (reference) NB CORESET#0 mentioned above. Specifically, all NB CORESET#0 replicas may have the same time / frequency structure, but their positions in the frequency domain may be distinguished by the F-offset. When NB CORESET#0 is duplicated X times for WB CORESET#0, NB bandwidth (B NB ), WB bandwidth(B WB ), and NB CORESET#0 bandwidth(B CORESET#0,NB Between ), the relationship based on the following 1) and 2) may be satisfied.

[0308] 1) B CORESET#0,NB <= B NB

[0309] 2) X*B CORESET#0,NB <= B WB

[0310] For example, the base station can set NB CORESET#0 within the NB terminal reception bandwidth and set a frequency gap (F-gap) when replicating NB CORESET#0 for WB UE.

[0311] For example, the base station can set NB CORESET#0 within the NB terminal reception bandwidth and select whether or not to include a frequency gap (F-gap) when cloning NB CORESET#0 for the WB UE. This will be explained in detail below with reference to FIG. 10.

[0312] FIG. 10 is a drawing illustrating a replication of a CORESET according to one embodiment of the present specification.

[0313] Specifically, (1) in FIG. 10 is an example of a replica of NB CORESET#0 when F-gap is not set (X=4 without F-gap). (2) in FIG. 10 is an example of a replica of NB CORESET#0 when F-gap is set (X=4 with F-gap).

[0314] For example, the F-gap can be generated / determined by the value of the F-offset.

[0315] For example, the F-gap can be set / defined separately. Specifically, the F-gap can be set / defined as the frequency gap between two adjacent NB CORESET#0s. As a specific example, the base station can set / instruct the terminal to set a separate parameter related to the F-gap. As a specific example, the parameter / information related to the F-gap can be defined in advance.

[0316] For example, Gap can be used to use a frequency range other than NB CORESET#0 within the NB terminal reception bandwidth for other DL signal / channel transmissions.

[0317] For example, continuous replication without gaps, and whether the NB UE can utilize (partial) of the replicated CORESET#0 in addition to the original CORESET#0 within the receiving bandwidth can be left to the terminal implementation.

[0318] More specific NB CORESET#0 replica setup / instruction methods may be as follows.

[0319] Setting the number and direction of NB CORESET#0 replicas: Replication can be performed in the higher frequency and / or lower frequency direction based on the above (reference) specific NB CORESET#0. To express the number and direction of replicas, a combination of replica counts X1 and X2 and + and - signs can be used to set / instruct. For example, based on {+2, -1}, 2 replicas in the higher frequency direction and 1 replica in the lower frequency direction can be set / instructed.

[0320] F-gap setting: For example, the F-gap can be set / defined identically between NB CORESET#0 replicas. Specifically, a single F-gap setting value can be applied identically. For example, the F-gap can be set / defined individually between NB CORESET#0 replicas. Specifically, the F-gap value can be set / indicated individually between NB CORESET#0 replicas through multiple F-gap values ​​(e.g., X-1 F-gap values ​​for replica X).

[0321] The above NB CORESET#0 replica configuration / setting parameters (e.g., NB CORESET#0 T / F structure, F-offset, F-gap) may be configured / instructed using broadcast signaling (e.g., PBCH-DMRS, PBCH payload (including MIB), SIB1 scheduling DCI, SIB1) and / or a dedicated sync raster. The term "dedicated sync raster method" may refer to the following operations. Specifically, when a terminal connects through a specific sync raster, the terminal may assume predefined parameter values ​​corresponding to that sync raster. It has the advantage of being able to signal at the earliest possible time and does not require a separate signaling OH for broadcast signaling, etc.

[0322] Depending on its BW capability (e.g., whether it supports WB / NB), the maximum number of NB CORESET#0 replicas that a terminal can use to receive PDCCH may vary. For example, an NB terminal can receive PDCCH and PDSCH scheduled through it (e.g., SIB1 PDSCH) within its own bandwidth (NB) (via NB CORESET#0). Meanwhile, a WB terminal can receive PDCCH and PDSCH scheduled through it (e.g., SIB1 PDSCH) within the WB (via one or more NB CORESET#0 replica(s). Alternatively, it may receive PDCCH through a single NB CORESET#0 and receive PDSCH scheduled to the WB (e.g., SIB1 PDSCH) through it.

[0323] [WB PDCCH transmission method using NB CORESET#0(s)]

[0324] In the methods below, let N be the number of NB CORESET#0 replicas configured within the WB. The number of NB CORESET#0 replicas M through which a PDCCH (hereinafter WB PDCCH) is transmitted or can be transmitted for actual WB UE(s) may be less than or equal to N. For example, out of the total N configured NB CORESET#0 replicas, M (≤N) may be configured / defined for use in WB PDCCH transmission. For example, in TDD or HD-FDD operations, only M (≤N) out of N may be valid due to conflicts with RO, dynamic UL transmissions (e.g., PUSCH, PUCCH, SRS), etc. For example, among the total N configured NB CORESET#0 replicas, N NB When allocating NB UE(s) for PDCCH (hereinafter NB PDCCH) transmission, the number of NB CORESET#0 replicas M to which WB PDCCH is transmitted or can be transmitted may be as follows.

[0325] The number of NB CORESET#0 replicas M is the number of NB CORESET#0 replicas dedicated to NB PDCCH N, derived from the total configured number of NB CORESET#0 replicas N. NB The number of subtracted can be less than or equal to M'.

[0326] M ≤ M'=NN NB

[0327] Among the total of N configured NB CORESET#0 replica(s), all or part of the M valid NB CORESET#0 replica(s) may be used, excluding invalid NB CORESET#0 replica(s) that cannot participate in actual WB PDCCH transmission due to various reasons including the examples listed above, base station conditions for NES, etc. Specifically, the base station may transmit WB PDCCH based on all or part of M (≤N) valid NB CORESET#0 replica(s). The following describes specific embodiments related to WB PDCCH.

[0328] The locations of M valid (or conversely invalid) NB CORESET#0 replica(s) to which WB PDCCH is transmitted or may be transmitted can be determined / set / indicated based on one of the following embodiments. For example, an index may be assigned to each NB CORESET#0 replica(s). For example, the index(s) for the NB CORESET#0 replica(s) may be designated as valid (or reserved) resources. For example, the index(s) for the NB CORESET#0 replica(s) may be indicated in the form of a bitmap or joint coding based on a predefined / set order.

[0329] The time / frequency region occupied by M NB CORESET#0 replicas can be defined as WB CORESET#0 from the perspective of the WB UE. For example, if there is a gap between CORESET#0 replicas, the time / frequency region may include the gap. For example, if there is a gap between CORESET#0 replicas, the gap may be excluded from the time / frequency region.

[0330] A method of specifying valid / reserved resources in NB CORESET units by further subdividing within WB CORESET#0 as proposed above, rather than the entire WB CORESET#0, may be useful for WB / NB terminals to perform operations such as PDSCH rate-matching by referring to the valid / reserved resource information in the NB CORESET units. Such valid / reserved resource information in the NB CORESET units may be set / defined based on the following embodiments.

[0331] For example, a base station can set / instruct valid / reserved resource information at the NB CORESET level to a terminal through broadcast signaling (e.g., PBCH payload, PBCH DM-RS, SIB1), dedicated / UE-specific RRC signaling, or a dedicated sync raster method. The dedicated sync raster method may refer to the following operations. Specifically, when a terminal connects through a specific sync raster, the terminal can assume valid / reserved resource information at the NB CORESET level that corresponds to that sync raster. It has the advantage of being able to signal at the earliest possible time and does not require a separate signaling OH for broadcast signaling, etc.

[0332] [Method #1: How to map / transfer WB PDCCH to a single NB CORESET#0]

[0333] Method #1 is a method in which the WB PDCCH is transmitted (all or almost) to one of M NB CORESET#0 replicas. According to the present embodiment, the base station transmits the WB PDCCH to at least one NB CORESET#0 replica among the M NB CORESET#0 replicas.

[0334] For example, the NB or NB CORESET#0 replica to which the WB PDCCH is transmitted can be (pre)configured / instructed to the WB UE.

[0335] For example, the terminal can perform BD on the NB or NB CORESET#0 replica to which the corresponding WB PDCCH is transmitted.

[0336] For example, M NB CORESET#0 replicas (with or without a gap) can be defined / assumed as a single WB CORESET#0. When a non-interleaved CCE-to-REG mapping and a hashing function are applied within WB CORESET#0, the base station can select an appropriate PDCCH candidate limited to a specific NB.

[0337] For example, a new hashing function (and CCE-to-REG mapping) can be defined and applied so that WB PDCCH candidates can be limited to NB.

[0338] When applying Method #1, the WB UE can determine the NB (CORESET#0 replica) for receiving the WB PDCCH based on one of the following methods 1) to 3).

[0339] 1) The terminal can determine the NB (CORESET#0 replica) for receiving WB PDCCH through BD.

[0340] 2) An NB (CORESET#0 replica) for receiving WB PDCCH can be determined based on a predefined rule. For example, an NB (CORESET#0 replica) for receiving WB PDCCH can be determined by applying a pre-configured / defined rule. For example, it can be determined as the lowest NB CORESET#0 replica or the highest NB CORESET#0 replica.

[0341] 3) Based on RRC settings or dynamic instructions (e.g., MAC CE, common / UE-specific DCI), an NB (CORESET#0 replica) for receiving WB PDCCH may be set / instructed / determined. For example, an NB CORESET#0 replica index, an NB index, etc. may be set / instructed.

[0342] According to one embodiment, in a situation where there is one or more (non-)overlapping NBs for different NB UEs within a WB, for the purpose of saving resources, a base station may transmit common / broadcast DCI / PDSCH for all NB / WB UEs based on a specific NB. The base station may instruct the WB UE to the specific NB.

[0343] According to one embodiment, in a situation where there is one or more (non-)overlapping NBs for different NB UEs within a WB, the base station can transmit common / broadcast DCI / PDSCH for NB UEs for each NB. The base station can transmit (additional) common / broadcast DCI / PDSCH for a WB UE to a specific NB. The WB UE can receive (additional) common / broadcast DCI / PDSCH through its NB CORESET#0.

[0344] [Method #2: Method for mapping / transferring WB PDCCH to M (>1) NB CORESET#0s]

[0345] Method #2 is a method in which WB PDCCH is mapped / transmitted to M (>1) NB CORESET#0s. Depending on how WB PDCCH is mapped / transmitted to M (>1) NB CORESET#0s, it can be subdivided into the following methods (Method #2-1, Method #2-2).

[0346] [Method #2-1: Method for mapping / transmitting Encoded DCI bits to M (>1) NB CORESET#0(s)]

[0347] WB PDCCH can be distributed and mapped / transmitted to M (>1) NB CORESET#0 replicas (in CCE or REG units). According to the present embodiment, the PDCCH blocking probability can be reduced. Specifically, by distributing and transmitting WB PDCCH to M NB CORESET#0 replicas, NB UEs that need to receive NB PDCCH through a single NB CORESET#0 replica can expect the effect of mitigating the blocking probability problem when receiving PDCCH.

[0348] [Method #2-1A: How to apply CCE and / or CCE-to-REG mapping by NB CORESET#0]

[0349] For example, M NB CORESET#0 replicas are configured for a WB UE, and each NB CORESET#0 replica(s) can be linked to a single CCE mapping and / or CCE-to-REG mapping.

[0350] For example, M (>1) NB CORESET#0 replicas may each have CCE mapping and / or CCE-to-REG mapping applied individually / independently. WB PDCCH may be distributed among the M NB CORESET#0 replicas based on a separate rule. Here, the separate rule may be based on a previously defined CCE-to-REG mapping method (e.g., TS 38.213 s7.3.2.2). Additionally, the separate rule may be a method that considers the NB CORESET#0 replica index (e.g., added as a parameter).

[0351] [Example of a separate rule] (NR CORESET#0 replica index-first mapping method)

[0352] To distribute and map WB PDCCH across M NB CORESET#0s for WB UE, an NB CORESET#0 replica index can be defined / configured. An NB CORESET#0 replica index-first mapping method can be applied.

[0353] NB The CORESET#0 replica index-first mapping method can be performed as follows. Starting from {lowest / highest CORESET#0 index, lowest / highest REG bundle index}, within the same REG bundle index, the CORESET#0 replica index is first increased / decreased by 1 to map, and then the REG bundle index is increased / decreased by 1, and the same process is repeated.

[0354] For example, assuming that the NB CORESET#0 replica index constituting WB CORESET#0 is m=0,1,2, ...,M-1 and the REG bundle index for each NB CORESET#0 replica is b=0,1,2, ...,B-1, and that it is the same for each NB CORESET#0 replica, the [m,b] combinations may be as follows.

[0355] [M-1,0] [M-1,1] [M-1,2] … [M-1.B-1]

[0356] …

[0357] [2,0] [2,1] [2,2] … [2, B-1]

[0358] [1,0] [1,1] [1,2] … [1, B-1]

[0359] [0,0] [0,1] [0,2] … [0, B-1]

[0360] Assuming the above [m,b] combination, the CCE-to-REG mapping for M NB CORESET#0s can be performed in the following order.

[0361] [0,0] -> [1,0] -> [2,0] -> … -> [M-1,0] -> [0,1] -> [1,1] -> ..

[0362] Specifically, for REG bundle index 0, the NB CORESET#0 replica index is mapped by increasing from 0 to M-1, and then the REG bundle index is increased by 1. For the REG bundle index (=1) which is 1 higher than the previous REG bundle index, the NB CORESET#0 replica index is mapped by increasing from 0 to M-1. After that, CCE-to-REG mapping can be performed in the same way.

[0363] The above replica index-first mapping method can be applied in a similar manner even when only CCE mapping is applied instead of CCE-to-REG mapping (specifically, when mapping is performed without a REG (bundle) interleaver). For example, the replica index-first mapping method described above can be applied by replacing the REG bundle index with a CCE index.

[0364] [Method #2-1A1]

[0365] CCE mapping can be performed for each of the M NB CORESET#0 replicas to construct K CCE indices (0 to K-1) for each NB CORESET#0 replica. Subsequently, based on a specific rule (e.g., applying the above NB CORESET#0 replica index-first mapping method at the CCE level rather than the REG bundle level), all M*K CCEs can be reordered into CCE indices 0 to M*K-1. A hashing function can be applied with a total of M*K CCEs. Consequently, a single virtual CORESET can be constructed across M NB (CORESET#0 replica) resources, comprising a total of M*K CCE indices 0 to M*K-1. In this state, PDCCH candidates for each AL can be constructed by applying a hashing function.

[0366] [Method #2-1A2]

[0367] (At a slightly smaller unit than the above method) For L REG bundle indices 0 to L-1 configured for each NB CORESET#0 replica, all M*L REG bundles can be re-indexed to indices 0 to M*L-1 based on a specific rule (e.g., applying the NR CORESET#0 replica index-first mapping method to the REG bundle unit). Subsequently, (additionally) (interleaved / non-interleaved) CCE-to-REG mapping can be performed on all M*L REG bundles. In this case as well, it can be viewed as if a single virtual CORESET is configured with CCE mapping / indexing performed across M NB CORESET#0 replica resources, and PDCCH candidates for each AL can be constructed by applying a hashing function in that state.

[0368] [Method #2-1A3]

[0369] (Unlike the two methods above) With CCE indexing and hashing (and the subsequent construction of PDCCH candidates) performed for each NB CORESET#0 replica, PDCCH candidates for the targets (per AL) on which the WB UE must perform BD can be formed by selecting them from multiple NB CORESET#0 replicas based on specific rules (e.g., evenly). For example, if the total number of PDCCH candidates in a specific AL is N PC If set to , approximately N from each of the M NB CORESET#0 replicas PC Select M PDCCH candidates (e.g., PC index 0 to N) PC / up to M-1), total N PCCan PDCCH candidates be configured. For more details, please refer to the examples below.

[0370] [Example of Method #2-1A3: Case of distributing to NBs on a PDCCH candidate basis]

[0371] All CCEs constituting a single PDCCH candidate can be extracted / determined from the same NB CORESET#0 replicas. Let M1 be the number of NB CORESET#0 replica(s) through which the PDCCH candidates of a specific AL are distributed. The number of PDCCH candidates distributed per NB CORESET#0 replica can be defined as follows.

[0372] Ceil(N PC N NB CORESET#0 replica(s) having / M1) PDCCH candidates PC -floor(N PC / M1)* M1

[0373] floor(N PC NB CORESET#0 replica(s) with / M1) PDCCH candidates (floor(N PC / M1)+1)* M1- N PC dog

[0374] In addition, the PDCCH candidate(s) of a specific AL can be distributed among the NB CORESET#0 replicas in the following order.

[0375] For example, starting from the lowest PDCCH candidate index per NB CORESET#0 replica and the lowest / highest NB (CORESET) index or lowest / highest frequency index, distribution can be performed in the order of increasing or decreasing the NB (CORESET#0 replica) index or frequency index. Subsequently, the same process can be repeated by increasing the PDCCH candidate index per NB (CORESET#0 replica).

[0376] [Method #2-1B: Method for applying a single CCE-to-REG mapping to the entire time / frequency domain of WB CORESET #0]

[0377] For example, a time / frequency domain occupied by M NB CORESET#0 replicas (excluding gaps if there are gaps between CORESET#0 replicas) can be defined as WB CORESET#0. The WB CORESET#0 can be associated with a single CCE-to-REG mapping.

[0378] For example, a continuous time / frequency domain containing M NB CORESET#0 replicas (specifically, including the gap if there is a gap between the NB CORESET#0 replicas) can be defined as WB CORESET#0. After interleaving the WB CORESET#0 by associating it with a single CCE-to-REG mapping, WB PDCCH can be transmitted only within the time / frequency domains belonging to the M NB CORESET#0s. Specifically, after interleaving, any time / frequency domains that do not belong to any NB CORESET#0 replica(s) are punctured, and WB PDCCH can be transmitted based on the remaining portion.

[0379] For example, puncturing can be performed considering terminal complexity, etc. As a specific example, puncturing can be performed in units of RB / REG / REG bundle / CCE (number of RBs occupied by it).

[0380] For example, the precoder granularity may be set / assumed / limited to sameAsREG-bundle, and puncturing may be performed at the REG bundle level. For example, the precoder granularity may be limited to allContiguousRBs to allow puncturing at the REG / RB level and to enable decoding even when some RBs are punctured within a REG bundle. (The definitions of sameAsREG-bundle and allContiguousRBs are in accordance with TS 38.211 s7.3.2.2). i) In the case of sameAsREG-bundle, the terminal may assume the same precoding being used within a REG bundle (UE may assume the same precoding being used within a REG bundle). ii) In the case of allContiguousRBs, the UE may assume the same precoding being used across all resource-element groups within the set of contiguous resource blocks in the CORESET.

[0381] To minimize (partial) collisions between NB CORESET#0 replicas and PDCCHs transmitted through WB CORESET#0 when Method #2-1B is supported, the interleaving unit (e.g., REG bundle) may be set / applied identically when applying the interleaved CC-to-REG mapping method / formula of NB CORESET#0 replicas and WB CORESET#0 (e.g., as in TS 38.211 Clause 7.3.2.2). For example, the interleaver row size (e.g., R as in TS 38.211 Clause 7.3.2.2) may also be set / applied identically. For example, to ensure the most even distribution among M NB CORESET#0 replicas, the interleaver row size of WB CORESET#0 may be set / limited to M or an integer multiple of M. For example, with the same intent, the R value of the NB CORESET#0 replica may be R NB , the R value for WB CORESET#0 is R WB If so, R WB The value of R NB Can be defined / set as *M

[0382] [Method #2-1C: Method for applying a single CCE-to-REG mapping to a portion of the time / frequency domain of WB CORESET #0]

[0383] A time / frequency range occupied by M NB CORESET#0 replicas can be defined as WB CORESET#0. For example, if there is a gap between NB CORESET#0 replicas in the said time / frequency range, the gap may be excluded or included. A portion of the time / frequency range of the said WB CORESET#0 may be associated with a single CCE-to-REG mapping. For example, a portion of the time / frequency range may be the first X OFDM symbol(s) and / or the lowest / highest Y RBs / REGs / REG bundles, etc. In this case, parameters (e.g., X, Y) for setting / indicating the portion of the time / frequency range may be (pre)set / indicated.

[0384] For example, the union of M NB CORESET#0 replicas can be defined as WB CORESET#0. Some time / frequency domains, rather than the entire WB CORESET#0, can be associated with a single CCE-to-REG mapping.

[0385] For example, WB CORESET#0 can be defined as part of the entire T / F region of M NB CORESET#0 replicas. The entire WB CORESET#0 can be associated with a single CCE-to-REG mapping.

[0386] For example, a continuous time / frequency domain containing M NB CORESET#0 replicas can be defined as WB CORESET#0. Specifically, if there are gaps between CORESET#0 replicas, WB CORESET#0 can be defined to include the gaps. After interleaving a portion of the continuous time / frequency domain of WB CORESET#0 by associating it with a single CCE-to-REG mapping, WB PDCCH can be transmitted only within the time / frequency domains belonging to the M NB CORESET#0(s). Specifically, the remaining time / frequency domains, excluding those belonging to the M NB CORESET#0(s), can be punctured.

[0387] Puncture can be performed in the same way as the puncturing method in Method #2-B above.

[0388] For example, puncturing can be performed considering terminal complexity, etc. As a specific example, puncturing can be performed in units of RB / REG / REG bundle / CCE (number of RBs occupied by it).

[0389] For example, precoder granularity may be set / assumed / qualified to sameAsREG-bundle, and puncturing may be performed at the REG bundle level. For example, precoder granularity may be qualified to allContiguousRBs to allow puncturing at the REG / RB level and to enable decoding even when some RBs are punctured within a REG bundle. (The definitions of sameAsREG-bundle and allContiguousRBs are in accordance with TS 38.211 s7.3.2.2).

[0390] Here, parameters for setting / instructing the time / frequency domain of WB CORESET#0 can be (pre)set / instructed.

[0391] When Method #2-1B is supported, the same interleaved CC-to-REG mapping method / formula is applied to the NB CORESET#0 replicas and WB CORESET#0 (e.g., as in TS 38.211 Clause 7.3.2.2), but the interleaving unit (e.g., REG bundle) may be configured / applied individually. For example, if the NB CORESET#0 replica and WB CORESET#0 consist of 3 OFDM symbols and 2 OFDM symbols, respectively, the interleaving unit (e.g., REG bundle) may be configured / instructed individually among {3, 6} and {2, 6}, respectively.

[0392] For example, the interleaver row size of WB CORESET#0 (e.g., R as in TS 38.211 Clause 7.3.2.2) may be assumed / set / applied to the same value as the NB CORESET#0 replica. For example, the interleaver row size of WB CORESET#0 may be set / limited to M or an integer multiple of M to ensure the most even distribution among M CORESET#0 replicas. For example, with the same intent, the value of R for the NB CORESET#0 replica is R NB In this case, the R value R for WB CORESET WB is R NB It can be set to *M.

[0393] [Method #2-2: Method for iteratively mapping / transmitting Encoded DCI bits to M (>1) NB CORESET#0(s)]

[0394] A PDCCH (specifically, NB PDCCH) mapped within one specific (reference) NB CORESET#0 replica for an NB UE can be repeatedly mapped to M-1 NB CORESET#0 replicas within the WB UE bandwidth, so that a WB PDCCH can be mapped / transmitted based on a total of M NB CORESET#0 replica(s). A CCE-to-REG mapping can be applied within the specific (reference) NB CORESET#0 replica, and can be interpreted as a form in which a kind of inter-NB FD repetition is applied between NBs (CORESET#0 replicas).

[0395] In the case of Method #2-2, instead of applying the CCE-to-REG mapping method / formula to the entire WB CORESET#0, the CCE-to-REG mapping can be applied (individually) to each of the M NB CORESET#0 replicas. The following two methods can be applied as the CCE-to-REG mapping method.

[0396] [CCE-to-REG Mapping Method]

[0397] Method #1: This method applies the same CCE-to-REG mapping to all NB CORESET#0 replicas. In this case, the advantage is that the transceiver operation is simple, and it can be said that the NB PDCCH is copied / duplicated to a total of M CORESET#0s for mapping.

[0398] Method #2: This method applies independent / different CCE-to-REG mapping to each NB CORESET#0 replica. It includes cases where the same CCE-to-REG mapping method / formula is applied, but different parameters are applied for each NB (CORESET#0), resulting in different outcomes after CCE-to-REG mapping. This method is expected to have the effect of avoiding the problem where a portion of the WB PDCCH may be continuously exposed to interference / collision due to other PDCCHs or external factors in a specific time / frequency range.

[0399] For example, time / frequency offset / shift values ​​(e.g., shiftIndex in TS 38.211 s7.3.2.2) for each NB CORESET#0 replica on the time / frequency axis can be (pre)set / instructed. For example, time / frequency offset / shift values ​​for each NB CORESET#0 replica can be determined / applied (within a specific range) through the generation / application of a pseudo-random number.

[0400] [Method to suppress BD increase for WB PDCCH reception]

[0401] For example, when applying the CCE-to-REG mapping method #2 of method #2-2, the number of terminal BD / CCEs may increase. Considering the burden of such a number of BD / CCEs, a method of scaling down the BD limit per NB to X / M can be considered, where X is the terminal BD capability and M is the number of NBs to be BDed.

[0402] For example, as mentioned in [CCE-to-REG Mapping Method] Method #2 above, CCE-to-REG mapping is performed individually for each NB (CORESET#0), but they are not completely independent and may have correlations with each other. As a specific example, a CCE-to-REG mapping method / formula is applied to a specific reference NB, and i) starting from that result, a circular shift is applied to other NBs (CORESET#0), or ii) an offset is applied to the nshift value of the REG bundle interleaver.

[0403] The base station may set / display parameters for the proposed methods (including information selected among the methods and detailed configuration parameters for method support) to the terminal through broadcast signaling (e.g., PBCH payload, PBCH DM-RS, SIB1), dedicated / UE-specific RRC signaling, or a dedicated sync raster method. The dedicated sync raster method may refer to the following operations. Specifically, when a terminal connects through a specific sync raster, the terminal may assume predefined parameter values ​​corresponding to that sync raster. It has the advantage of being able to signal at the earliest possible time and does not require a separate signaling OH for broadcast signaling, etc.

[0404] In terms of implementation, operations of a base station / terminal according to the embodiments described above (e.g., operations based on at least one of Method #1, Method #2-1 (Method #2-1A, Method #2-1B, Method #2-1C) and / or Method #2-2) may be processed by the device of FIG. 13 described below (e.g., the processor (110, 210) of FIG. 13).

[0405] 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 #1, Method #2-1 (Method #2-1A, Method #2-1B, Method #2-1C) and / or Method #2-2) may be stored in memory (e.g., 140, 240 of FIG. 13) in the form of instructions / programs (e.g., instruction, executable code) for driving at least one processor (e.g., 110, 210 of FIG. 13).

[0406] The embodiments described above will be explained in detail below with reference to FIGS. 11 and FIGS. 12 in terms of the operation of the terminal / base station. The methods described below are distinguished only for convenience of explanation, and it is understood that a part of one method may be substituted with a part of another method or combined with one another and applied.

[0407] FIG. 11 is a flowchart for explaining a method performed by a terminal according to one embodiment of the present specification.

[0408] Referring to FIG. 11, a method performed by a terminal according to one embodiment of the present specification includes the step of determining first CORESETs (S1110) and the step of receiving a PDCCH based on the first CORESETs (S1120).

[0409] In S1110, the terminal determines the first control resource sets (Control REsource SET, CORESET).

[0410] In S1120, the terminal receives a Physical Downlink Control Channel (PDCCH) from the base station based on the first CORESETs.

[0411] The above first CORESETs may be based on Method #2. For example, the above first CORESETs may be based on M(>1) CORESETs (or M(>1) CORESET#0s). This will be explained in detail below.

[0412] According to one embodiment, the time-frequency structure associated with the first CORESETs may be determined based on the replication of the time-frequency structure of the second CORESET associated with a specific control resource set ID. The reception of the PDCCH may be associated with a first bandwidth. The second CORESET may be associated with a second bandwidth smaller than the first bandwidth. The CCE-to-REG mapping associated with the PDCCH may be applied based on rules associated with the first CORESETs. This embodiment may be based on one of Methods #2-1A to #2-1C. The CCE-to-REG mapping method is described in detail below.

[0413] According to one embodiment, the CCE-to-REG mapping may be applied separately to each of the first CORESETs. This embodiment may be based on Method #2-1A.

[0414] For example, for the same REG bundle index, the CCE-to-REG mapping may be performed based on the order of indices associated with the first CORESETs. More specifically, for the same REG bundle index (a REG bundle index increased by 1 from the previous REG bundle index), the CCE-to-REG mapping may be performed based on the order (ascending or descending) of indices associated with the first CORESETs. This embodiment may be based on the NR CORESET#0 replica index-first mapping method described above. The indices associated with the first CORESETs may be based on the NB CORESET#0 replica index m=0,1,2,M-1 described above.

[0415] According to one embodiment, the CCE-to-REG mapping may be applied to the entire time-frequency domain based on the first CORESETs. This embodiment may be based on Method #2-1B.

[0416] For example, the entire time-frequency region may be a time-frequency region occupied by the first CORESETs (e.g., a region excluding the gap if there is a gap).

[0417] For example, the entire time-frequency domain may be a continuous time-frequency domain including the first CORESETs (e.g., a region including the gap if there is a gap). Here, the gap may refer to the F-gap of FIG. 10.

[0418] According to one embodiment, the CCE-to-REG mapping may be an interleaved CCE-to-REG mapping. The first CORESETs may be obtained by applying the interleaved CCE-to-REG mapping to the entire time-frequency domain and then applying puncturing. This embodiment may be based on Method #2-1B.

[0419] For example, the above puncturing can be performed in units of RB / REG / REG bundle / CCE. Specifically, the time-frequency domain to which the above puncturing is applied can be determined in units of i) Resource Block (RB), ii) REG, iii) REG bundle, or iv) CCE.

[0420] As a specific example, the time-frequency domain to which the above puncturing is applied can be determined at the REG bundle level. In this case, the precoder granularity can be assumed / set to sameAsREG-bundle. Specifically, it can be assumed that the same precoding is used within a single REG bundle.

[0421] As a specific example, the time-frequency domain to which the above puncturing is applied may be determined in units of the above RB or the above REG. In this case, the precoder granularity may be assumed / set to allContiguousRBs. Specifically, it may be assumed that the same precoding is used across all resource element groups within a set of contiguous resource blocks in a first CORESET.

[0422] According to one embodiment, the CCE-to-REG mapping may be performed based on a value identical to the value set for the second CORESET. This embodiment may be based on Method #2-1B. The value set for the second CORESET may include i) REG bundling size (e.g., the interleaving unit described above) and / or ii) interleaver size (e.g., interleaver row size R).

[0423] According to one embodiment, the CCE-to-REG mapping may be performed based on a value that is M times the interleaver size set for the second CORESET. M may be the number of the first CORESETs. This embodiment may be based on Method #2-1B. For example, the interleaver size set for the second CORESET is the R described above. NB It can mean.

[0424] According to one embodiment, the CCE-to-REG mapping may be applied to a portion of the entire time-frequency domain based on the first CORESETs. This embodiment may be based on Method #2-1C.

[0425] According to one embodiment, the second CORESET may be CORESET#0 or CORESET#n (n≠0). Specifically, the value of the specific control resource set ID may be 0 or n. n may be a positive integer. For example, the specific control resource set ID may be based on the ControlResourceSetId used to identify the CORESET.

[0426] The operation based on S1110 to S1120 described above can be implemented by the device of FIG. 13. For example, the terminal (200) can control one or more transceivers (230) and / or one or more memories (240) to perform the operation based on S1110 to S1120.

[0427] The embodiments described above will be explained in detail below in terms of base station operation.

[0428] S1210 described below corresponds to S1110 to S1120 described in FIG. 11. Considering the above correspondence, redundant descriptions are omitted. That is, the specific description of the base station operation described below can be replaced by the description / embodiment of FIG. 11 corresponding to the operation.

[0429] FIG. 12 is a flowchart illustrating a method performed by a base station according to another embodiment of the present specification.

[0430] Referring to FIG. 12, a method performed by a base station according to another embodiment of the present specification includes the step (S1210) of transmitting a PDCCH based on first CORESETs.

[0431] In S1210, the base station transmits a Physical Downlink Control Channel (PDCCH) to the terminal based on the first Control Resource Set (CORESET).

[0432] The first CORESETs mentioned above may be based on Method #2. For example, the first CORESETs may be based on M(>1) CORESETs (or M(>1) CORESET#0s).

[0433] According to one embodiment, the time-frequency structure associated with the first CORESETs may be determined based on the replication of the time-frequency structure of the second CORESET associated with a specific control resource set ID. The transmission of the PDCCH may be associated with a first bandwidth. The second CORESET may be associated with a second bandwidth smaller than the first bandwidth. The CCE-to-REG mapping associated with the PDCCH may be applied based on rules associated with the first CORESETs.

[0434] In the above method, the operation of determining the first CORESETs is omitted, assuming that the base station is aware of all information regarding the CORESETs to be used to transmit the PDCCH. However, it may be assumed that the base station is defined / implemented to determine the CORESETs whenever it transmits a PDCCH for a specific terminal in a first bandwidth (e.g., WB). In this case, the method of FIG. 12 may include the step of determining the first CORESETs and the step of transmitting the PDCCH based on the first CORESETs, just like the method of FIG. 11.

[0435] The operation based on the above-described S1210 can be implemented by the device of FIG. 13. For example, a base station (100) can control one or more transceivers (130) and / or one or more memories (140) to perform the operation based on S1210.

[0436] Hereinafter, an apparatus to which the embodiments of the present specification can be applied (an apparatus implementing the method / operation according to the embodiments of the present specification) will be described with reference to FIG. 13.

[0437] FIG. 13 is a drawing showing the configuration of a first device and a second device according to an embodiment of the present specification.

[0438] The first device (100) may include a processor (110), an antenna unit (120), a transceiver (130), and a memory (140).

[0439] The processor (110) performs baseband-related signal processing and may include an upper layer processing unit (111) and a physical layer processing unit (115). The upper layer processing unit (111) may process operations of the MAC layer, RRC layer, or higher upper layers. The physical layer processing unit (115) may process operations of the PHY layer. For example, if 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, if the first device (100) is a first terminal device in terminal-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).

[0440] The antenna section (120) may include one or more physical antennas, and if 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, operating systems, applications, etc. related to the operation of the first device (100), and may include components such as a buffer.

[0441] The processor (110) of the first device (100) may be configured to implement the operation of the base station in base station-terminal communication (or the operation of the first terminal device in terminal-terminal communication) in the embodiments described in this disclosure.

[0442] The second device (200) may include a processor (210), an antenna unit (220), a transceiver (230), and a memory (240).

[0443] The processor (210) performs baseband-related signal processing and may include an upper layer processing unit (211) and a physical layer processing unit (215). The upper layer processing unit (211) may process operations of the MAC layer, RRC layer, or higher upper layers. The physical layer processing unit (215) may process operations of the PHY layer. For example, if 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, if the second device (200) is a second terminal device in terminal-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).

[0444] The antenna section (220) may include one or more physical antennas, and may support MIMO transmission and reception if it includes multiple antennas. The transceiver (230) may include an RF transmitter and an RF receiver. The memory (240) may store information processed by the processor (210) and software, operating systems, applications, etc. related to the operation of the second device (200), and may include components such as a buffer.

[0445] The processor (210) of the second device (200) may be configured to implement the operation of the terminal in base station-terminal communication (or the operation of the second terminal device in terminal-terminal communication) in the embodiments described in this disclosure.

[0446] In the operation of the first device (100) and the second device (200), the details described in the examples of the present disclosure regarding the base station and terminal (or the first terminal and the second terminal in terminal-to-terminal communication) in base station-to-terminal communication may be applied in the same way, and redundant descriptions are omitted.

[0447] Here, the wireless communication technology implemented in the device (100, 200) of the present disclosure may include LTE, NR, and 6G, as well as 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 according to standards such as LTE Cat NB1 and / or LTE Cat NB2, but is not limited to the names mentioned above.

[0448] 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 referred to by various names such as eMTC (enhanced Machine Type Communication). For example, LTE-M technology may be implemented in 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 names mentioned above.

[0449] Additionally or generally, 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) for low-power communication, but is not limited to the names mentioned above. 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. Regarding the method, A step of determining first control resource sets (Control REsource SET, CORESET); and The method includes the step of receiving a Physical Downlink Control Channel (PDCCH) based on the first CORESETs above, wherein The time-frequency structure associated with the first CORESETs is determined based on the replication of the time-frequency structure of the second CORESET associated with a specific control resource set ID, and The reception of the above PDCCH is associated with a first bandwidth, and the second CORESET is associated with a second bandwidth smaller than the first bandwidth, and A method characterized in that the CCE-to-REG mapping (Control Channel Element, CCE-to-Resource Element Group, REG, mapping) associated with the above PDCCH is applied based on rules associated with the above first CORESETs.

2. In Paragraph 1, A method characterized in that the above CCE-to-REG mapping is applied separately to each of the above first CORESETs.

3. In Paragraph 2, A method characterized in that, for the same REG bundle index, the CCE-to-REG mapping is performed based on the order of the indices associated with the first CORESETs.

4. In Paragraph 1, A method characterized in that the above CCE-to-REG mapping is applied to the entire time-frequency domain based on the above first CORESETs.

5. In Paragraph 4, The above CCE-to-REG mapping is an interleaved CCE-to-REG mapping, and A method characterized in that the first CORESETs are obtained by applying the interleaved CCE-to-REG mapping to the entire time-frequency domain and then applying puncturing.

6. In Paragraph 5, A method characterized in that the time-frequency domain to which the above puncturing is applied is determined in units of i) a Resource Block (RB), ii) a REG, iii) a REG bundle, or iv) a CCE.

7. In Paragraph 6, The time-frequency domain to which the above puncturing is applied is determined in units of the above REG bundle, and A method characterized by assuming that the same precoding is used within a single REG bundle.

8. In Paragraph 6, The time-frequency domain to which the above puncturing is applied is determined in the units of the above RB or the above REG, and A method characterized by assuming that the same precoding is used across all REGs in a set of consecutive resource blocks within a single first CORESET.

9. In Paragraph 4, The above CCE-to-REG mapping is performed based on a value identical to the value set for the second CORESET, and A method characterized in that the value set for the second CORESET includes i) REG bundling size and / or ii) interleaver size.

10. In Paragraph 4, The above CCE-to-REG mapping is performed based on a value that is M times the interleaver size set for the second CORESET, and A method characterized in that the above M is the number of the above first CORESETs.

11. In Paragraph 1, A method characterized in that the above CCE-to-REG mapping is applied to a portion of the entire time-frequency domain based on the above first CORESETs.

12. In Paragraph 1, A method characterized in that the value of the specific control resource set ID is 0 or n, and n is a positive integer.

13. In the terminal, One or more transmitters / receivers; One or more processors; and It includes one or more memories connected to the above one or more processors and storing instructions, A terminal characterized by the above instructions being set so that the terminal performs all steps of the method according to any one of claims 1 to 12, based on execution by the one or more processors.

14. An apparatus comprising one or more memories and one or more processors functionally connected to the one or more memories, An apparatus characterized in that the above one or more memories store instructions that set the one or more processors to perform all steps of the method according to any one of claims 1 to 12, based on execution by the above one or more processors.

15. In one or more non-transitory computer-readable media storing instructions, One or more non-transitory computer-readable media characterized by instructions executable by one or more processors, wherein the one or more processors are configured to perform all steps of the method according to any one of claims 1 to 12.

16. Regarding the method, The method includes the step of transmitting a Physical Downlink Control Channel (PDCCH) based on first Control Resource Sets (CORESET); The time-frequency structure associated with the first CORESETs is determined based on the replication of the time-frequency structure of the second CORESET associated with a specific control resource set ID, and The transmission of the above PDCCH is associated with a first bandwidth, and the second CORESET is associated with a second bandwidth smaller than the first bandwidth, and A method characterized in that the CCE-to-REG mapping (Control Channel Element, CCE-to-Resource Element Group, REG, mapping) associated with the above PDCCH is applied based on rules associated with the above first CORESETs.

17. Regarding base stations, One or more transmitters / receivers; One or more processors; and It includes one or more memories connected to the above one or more processors and storing instructions, A base station characterized by the above instructions being set so that the one or more processors perform all steps of the method according to claim 16, based on execution by the one or more processors.

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