Method, terminal, device, and storage medium for monitoring a control channel in a wireless communication system, and method and base station for transmitting a control channel

Abstract

According to the present invention, a terminal switches a search space set of a first SSSG to a search space of a second SSSG at a search space set group (SSSG) switching time, and performs PDCCH monitoring for at least one serving cell. When PDCCH monitoring is performed on a slot-group basis for the at least one serving cell, the terminal determines the SSSG switching time based on a maximum Xs value among Xs values ​​for the at least one serving cell.

Description

Technical Field

[0001] The present invention relates to a method and an apparatus used in a wireless communication system.

Background Art

[0002] Wireless communication systems have been widely deployed to provide various communication services such as voice and data. Generally, a wireless communication system is a multiple connection (multiple access) system that can share available system resources (bandwidth, transmission power, etc.) to assist communication with multiple users. Examples of multiple connection systems include CDMA (code division multiple access) systems, FDMA (frequency division multiple access) systems, TDMA (time division multiple access) systems, OFDMA (orthogonal frequency division multiple access) systems, SC-FDMA (single carrier frequency division multiple access) systems, and the like.

Summary of the Invention

Problems to be Solved by the Invention

[0003] The technical problem to be achieved by the present invention is to provide a control channel monitoring method and an apparatus therefor, and a method for transmitting a control channel and an apparatus therefor, for efficiently monitoring a control channel in a wireless communication system.

[0004] The technical problem of the present invention is not limited to the above-described technical problem, and other technical problems can be inferred from the embodiments of the present invention.

Means for Solving the Problems

[0005] The present invention provides a method for a terminal to monitor a control channel in a wireless communication system.

[0006] As another aspect of the present invention, a terminal for monitoring a control channel in a wireless communication system is provided. The terminal includes at least one transceiver, at least one processor, and at least one computer memory operably connected to the at least one processor and configured to cause the at least one processor to perform operations when executed.

[0007] As yet another aspect of the present invention, an apparatus for a terminal is provided. The apparatus includes at least one processor and at least one computer memory operably connected to the at least one processor and configured to cause the at least one processor to perform operations when executed.

[0008] As yet another aspect of the present invention, a computer-readable non-transitory storage medium including at least one computer program configured to cause at least one processor to perform operations is provided.

[0009] As yet another aspect of the present invention, a method for a base station to transmit a control channel in a wireless communication system is provided.

[0010] As yet another aspect of the present invention, a base station for transmitting a control channel in a wireless communication system is provided.

[0011] The method in the terminal, or the operation performed by executing an instruction stored in at least one memory or storage medium of the terminal or the device for the terminal, includes receiving a search space configuration for at least one serving cell (e.g., a serving cell or a set of serving cells), where the search space configuration includes settings related to at least one search space set belonging to a first search space set group (SSSG) having at least a first group index and settings related to at least one search space set belonging to a second SSSG having a second group index. Based on the search space configuration, performing physical downlink control channel (PDCCH) monitoring according to the search space set of the first SSSG for the at least one serving cell, and performing SSSG switching based on detecting a DCI format for notifying SSSG switching for the at least one serving cell, or based on a timer related to SSSG switching expiring. Based on the at least one serving cell including a serving cell having a subcarrier spacing of 960 kHz, the SSSG switching is at least a predetermined number P from the last symbol of the PDCCH having the DCI format switchAt the beginning of the first slot of the slot-group of Xs slots after the

[0012] individual symbols, including: i) stopping the PDCCH monitoring according to the search space set of the first SSSG; and ii) starting the PDCCH monitoring according to the search space set of the second SSSG, where the slot-group of the Xs slots is consecutive. Based on the fact that the at least one serving cell includes a serving cell having the 960 kHz subcarrier spacing, for the SSSG switching, the terminal or the operation determines the slot for stopping or starting the PDCCH monitoring and the symbol within the slot based on the maximum Xs value among the Xs values (e.g., the Xs values associated / set for the at least one serving cell) for the at least one serving cell.

[0012] The method in the base station, or the operation performed by executing an instruction stored in at least one memory of the base station, includes transmitting a search space configuration for at least one serving cell (e.g., a serving cell or a serving cell set), where the search space configuration includes a configuration regarding at least one search space set belonging to a first search space set group (SSSG) having at least a first group index and a configuration regarding at least one search space set belonging to a second SSSG having a second group index. Based on the search space configuration, transmitting at least one physical downlink control channel (PDCCH) according to the search space set of the first SSSG for the at least one serving cell, and performing the SSSG switching based on transmitting a DCI format for notifying the SSSG switching to the at least one serving cell or based on the expiration of a timer regarding the SSSG switching. Based on the at least one serving cell including a serving cell having a subcarrier spacing of 960 kHz, the SSSG switching is at least a predetermined number P from the last symbol of the PDCCH having the DCI format switchAt the beginning of the first slot of the slot-group of Xs slots after a symbol, i) stop transmitting at least one PDCCH according to the search space set of the first SSSG, and ii) start transmitting at least one PDCCH according to the search space set of the second SSSG, where the slot-group of the Xs slots is consecutive. Based on the fact that the at least one serving cell includes a serving cell having the 960 kHz subcarrier spacing, the base station or the operation determines the slot in which the SSSG switching is performed and the symbol in the slot based on the maximum Xs value among the Xs values (e.g., the Xs value associated / set for the at least one serving cell) for the at least one serving cell.

[0013] In each aspect of the present invention, a switch cell group setting is provided by the base station to the terminal. When the switch cell group setting is provided, the at least one serving cell is a serving cell set. Based on the switch cell group setting, the SSSG switching is performed for all serving cells within the serving cell set.

[0014] In each aspect of the present invention, the switch cell group setting is the radio resource control (RRC) parameter cellGroupForSwitch.

[0015] In each aspect of the present invention, the predetermined number P switch related information is provided by the base station to the terminal.

[0016] In each aspect of the present invention, the predetermined number P switch is predefined for the 960 kHz subcarrier spacing and the processing capability of the terminal.

[0017] In each aspect of the present invention, each search space set in the first SSSG and the second SSSG is set based on one of the Xs values among the Xs values for the at least one serving cell.

[0018] In each aspect of the present invention, each of the Xs values for the at least one serving cell is related to the search space set configured for the at least one serving cell.

[0019] In each aspect of the present invention, information regarding the position of the SSSG flag field in the DCI format for the at least one serving cell is provided by the base station to the terminal.

[0020] In each aspect of the present invention, the DCI format is DCI format 2_0.

[0021] The above-described aspects of the present invention are merely part of the preferred embodiments of the present invention, and various embodiments reflecting the technical features of the present invention can be derived and understood by those having ordinary knowledge in the art based on the detailed description of the present invention described below.

Advantages of the Invention

[0022] According to an embodiment of the present invention, a terminal can perform more efficient control signal monitoring.

[0023] The technical effects of the present invention are not limited to the above-described technical effects, and other technical effects can be inferred from the embodiments of the present invention.

Brief Description of the Drawings

[0024]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

Figure 10

Figure 11

Embodiments for Carrying Out the Invention

[0025] The following technologies can be used in various wireless connection systems such as CDMA, FDMA, TDMA, OFDMA, SC-FDMA, etc. CDMA can be implemented by wireless technologies such as UTRA (Universal Terrestrial Radio Access) and CDMA2000. TDMA can be implemented by 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 by wireless technologies such as IEEE 802.11 (Wi-Fi), IEEE 802.16 (WiMAX), IEEE 802-20, E-UTRA (Evolved UTRA), etc. UTRA is part of UMTS (Universal Mobile Telecommunications System). 3GPP (registered trademark) (3rd Generation Partnership Project) LTE (long term evolution) is part of E-UMTS (Evolved UMTS) that uses E-UTRA, and LTE-A (Advanced) / LTE-A pro is an evolved version of 3GPP LTE. 3GPP NR (New Radio or New Radio Access Technology) is an evolved version of 3GPP LTE / LTE-A / LTE-A pro.

[0026] For a clearer explanation, the description is based on the 3GPP communication system (e.g., LTE-A, NR), but the technical idea of the present invention is not limited thereto. LTE means the technology after 3GPP TS 36.xxx Release 8. Specifically, the LTE technology after 3GPP TS 36.xxx Release 10 is called LTE-A, and the LTE technology after 3GPP TS 36.xxx Release 13 is called LTE-A pro. 3GPP NR means the technology after TS 38.xxx Release 15. LTE / NR can also be referred to as the 3GPP system. "xxx" means the detailed number of the standard document. LTE / NR is collectively referred to as the 3GPP system. For the background technology, terms, abbreviations, etc. used in the description of the present invention, reference can be made to the matters described in the standard documents published before the present invention. For example, the following documents can be referred to.

[0027] 3GPP NR

[0028] -38.211: Physical channels and modulation

[0029] -38.212: Multiplexing and channel coding

[0030] -38.213: Physical layer procedures for control

[0031] -38.214: Physical layer procedures for data

[0032] -38.300: NR and NG-RAN Overall Description

[0033] -38.331: Radio Resource Control(RRC) protocol specification

[0034] FIG. 1 illustrates the structure of a radio frame used in NR.

[0035] In NR, the transmissions of the uplink (UL) and downlink (DL) are composed of frames. A radio frame has a length of 10 ms and is defined as two 5-ms half-frames (HF). A half-frame is defined as five 1-ms subframes (SF). A subframe is divided into one or more slots, and the number of slots in a subframe depends on the subcarrier spacing (SCS). Each slot contains 12 or 14 OFDM(A) symbols by means of a cyclic prefix (CP). When normal CP is used, each slot contains 14 symbols. When extended CP is used, each slot contains 12 symbols. Here, the symbol can include an OFDM symbol (or a CP-OFDM symbol), an SC-FDMA symbol (or a DFT-s-OFDM symbol).

[0036] Table 1 illustrates that when normal CP is used, the number of symbols per slot, the number of slots per frame, and the number of slots per subframe change according to the SCS.

[0037] [Table 1]

[0038] Table 2 illustrates that when extended CP is used, the number of symbols per slot, the number of slots per frame, and the number of slots per subframe change according to the SCS.

[0039] [Table 2]

[0040] In the NR system, the settings of OFDM(A) numerology (e.g., SCS, CP length, etc.) are different among multiple cells merged into one terminal (User Equipment; UE). As a result, the (absolute time) intervals of time resources (e.g., SF, slot, or TTI) (collectively referred to as TU (Time Unit) for convenience) composed of the same number of symbols are different among the merged cells.

[0041] NR supports a number of OFDM (Orthogonal Frequency Division Multiplexing) numerologies (e.g., subcarrier spacing, SCS) to support various 5G services. For example, when the SCS is 15 kHz, it supports a wide area in the traditional cellular band, and when the SCS is 30 kHz / 60 kHz, it supports dense-urban areas, lower latency, and wider carrier bandwidth.

[0042] The NR frequency band is defined by two types of frequency ranges (FR1 / FR2). FR1 / FR2 is configured as shown in Table 3 below. Also, FR2 means millimeter wave (mmW).

[0043]

Table 3

[0044] Figure 2 illustrates the slot structure of the NR frame.

[0045] A slot contains a plurality of symbols in the time domain. For example, in the case of normal CP, one slot contains 14 symbols, while in the case of extended CP, one slot contains 12 symbols. A carrier contains a plurality of subcarriers in the frequency domain. An RB (Resource Block) is defined as a plurality (e.g., 12) of consecutive subcarriers in the frequency domain. In the frequency domain, a plurality of RB interleaves (simply, interleaves) are defined. An interleave m ∈ {0, 1,..., M - 1} is composed of (common) RBs {m, M + m, 2M + m, 3M + m,...}. M indicates the number of interleaves. A BWP (Bandwidth Part) is defined as a plurality of consecutive RBs (e.g., physical RBs, PRBs) in the frequency domain and can correspond to one OFDM numerology (e.g., SCS(u), CP length, etc.). A carrier contains a maximum of N (e.g., 5) BWPs. Data communication is performed on the activated BWP, and only one BWP is activated for one terminal within one cell / carrier. Each element in the resource grid is referred to as a resource element (Resource Element, RE), and one modulation symbol can be mapped thereto.

[0046] In a wireless communication system, a terminal receives information from a base station via the downlink (DL), and the terminal transmits information to the base station via the uplink (UL). The information transmitted and received by the base station and the terminal includes data and various control information, and various physical channels / signals exist depending on the type / usage of the information they transmit and receive. A physical channel corresponds to a set of resource elements (REs) that carry information derived from the upper layer. A physical signal corresponds to a set of resource elements (REs) used by the physical layer (PHY) but does not carry information derived from the upper layer. The upper layer includes the MAC (Medium Access Control) layer, RLC (Radio Link Control) layer, PDCP (Packet Data Convergence Protocol) layer, RRC (Radio Resource Control) layer, etc.

[0047] The DL physical channels include PBCH (Physical Broadcast channel), PDSCH (Physical Downlink Shared channel), and PDCCH (Physical Downlink Control channel). The DL physical signals include DL RS (Reference Signal), PSS (Primary synchronization signal), and SSS (Secondary synchronization signal). The DL RS includes DM-RS (Demodulation RS), PT-RS (Phase-tracking RS), and CSI-RS (channel-state information RS). The UL physical channels include PRACH (Physical Random Access Channel), PUSCH (Physical Uplink Shared Channel), and PUCCH (Physical Uplink Control Channel). The UL physical signals include UL RS. The UL RS includes DM-RS, PT-RS, and SRS (Sounding RS).

[0048] Figure 3 shows an example of the mapping of physical channels within a slot.

[0049] One slot contains all of the DL control channel, DL or UL data, UL control channel, etc. For example, in the slot, the first N symbols are used for transmitting the DL control channel (hereinafter, DL control region), and the last M symbols in the slot are used for transmitting the UL control channel (hereinafter, UL control region). N and M are each integers of 0 or more. The resource region (hereinafter, data region) between the DL control region and the UL control region is used for transmitting DL data or for transmitting UL data. There is a time gap for DL-to-UL or UL-to-DL switching between the control region and the data region. PDCCH is transmitted in the DL control region, and PDSCH is transmitted in the DL data region. Some symbols at the time of conversion from DL to UL within the slot are used as the time gap.

[0050] In the present invention, the base station is, for example, a gNodeB.

[0051] Downlink (DL) Physical Channel / Signal

[0052] (1) PDSCH

[0053] The PDSCH carries downlink data (e.g., DL-shared channel transport block, DL-SCH TB). After the TB is encoded into codewords (CW), it is transmitted through processes such as scrambling and modulation. A CW contains one or more code blocks (CB). One or more CBs are grouped into one 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 is mapped to resources together with DMRS through precoding and transmitted on the corresponding antenna port. The PDSCH is dynamically scheduled by the PDCCH (dynamic scheduling), or semi-statically scheduled (Configured Scheduling, CS) based on upper layer (e.g., RRC) signaling (and / or Layer 1 (L1) signaling (e.g., PDCCH)). Therefore, in dynamic scheduling, the PDSCH transmission is accompanied by the PDCCH, while in CS, the PDSCH transmission is not accompanied by the PDCCH. CS includes SPS (semi-persistent scheduling).

[0054] (2) PDCCH

[0055] The PDCCH carries DCI (Downlink Control Information). For example, the PCCCH (i.e., DCI) carries information such as the transmission format and resource allocation of the DL-SCH, frequency / time resource allocation information for the UL-SCH (shared channel), paging information regarding the PCH (paging channel), system information on the DL-SCH, frequency / time resource allocation information regarding upper layer control messages such as any connection response (RAR) transmitted on the PDSCH, transmission power control commands, and information regarding the activation / deactivation of SPS / CS (Configured Scheduling). Different DCI formats are provided by the information in the DCI.

[0056] Table 4 illustrates the DCI formats transmitted via the PDCCH.

[0057] [Table 4]

[0058] DCI format 0_0 is used to schedule the TB-based (or TB-level) PUSCH, and DCI format 0_1 is used to schedule the TB-based (or TB-level) PUSCH or the CBG (Code Block Group)-based (or CBG-level) PUSCH. DCI format 1_0 is used to schedule the TB-based (or TB-level) PDSCH, and DCI format 1_1 is used to schedule the TB-based (or TB-level) PDSCH or the CBG-based (or CBG-level) PDSCH (DL grant DCI). DCI formats 0_0 / 0_1 are referred to as UL grant DCI or UL scheduling information, and DCI formats 1_0 / 1_1 are 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 the terminal, and DCI format 2_1 is used to transmit downlink pre-emption information to the terminal. DCI format 2_0 and / or DCI format 2_1 are transmitted to the terminals within the corresponding group via the group common PDCCH, which is the PDCCH defined as a group and transmitted to the terminals in the group.

[0059] The PDCCH / DCI includes a CRC (cyclic redundancy check), and the CRC is masked / scrambled with various identifiers (e.g., Radio Network Temporary Identifier, RNTI) depending on the owner or usage purpose of the PDCCH. For example, if the PDCCH is for a specific terminal, the CRC is masked with the C-RNTI (Cell-RNTI). If the PDCCH is related to paging, the CRC is masked with the P-RNTI (Paging-RNTI). If the PDCCH is related to system information (e.g., System Information Block, SIB), the CRC is masked with the SI-RNTI (System Information RNTI). If the PDCCH is related to the random access response, the CRC is masked with the RA-RNTI (Random Access-RNTI).

[0060] Table 5 illustrates the uses and transmission channels of the PDCCH by RNTI. The transmission channel indicates the transmission channel related to the data carried by the PDSCH / PUSCH scheduled by the PDCCH.

[0061]

Table 5

[0062] The modulation scheme of the PDCCH is fixed (e.g., Quadrature Phase Shift Keying, QPSK), and one PDCCH is composed of 1, 2, 4, 8, or 16 CCEs (Control Channel Elements) according to the AL (Aggregation Level). One CCE is composed of 6 REGs (Resource Element Groups). One REG is defined by one OFDM symbol and one (P)RB.

[0063] The PDCCH is transmitted on a CORESET (Control Resource Set). The CORESET corresponds to a set of physical resources / parameters used to carry PDCCH / DCI within a BWP. For example, the CORESET includes a set of REGs having a predetermined numerology (e.g., SCS, CP length, etc.). The CORESET is configured by system information (e.g., MIB) or terminal-specific (UE-specific) upper layer (e.g., RRC) signaling. Examples of parameters / information used for CORESET configuration are as follows. One or more CORESETs are configured for one terminal, and multiple CORESETs are superimposed in the time / frequency domain.

[0064] - controlResourceSetId: Indicates the identification information (ID) of the CORESET.

[0065] - frequencyDomainResources: Indicates the frequency domain resources of the CORESET. It is indicated by a bitmap, and 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 groups corresponding to the bits with a bit value of 1 are allocated as the frequency domain resources of the CORESET.

[0066] - duration: Indicates the time domain resources of the CORESET. It indicates the number of consecutive OFDMA symbols that constitute the CORESET. For example, duration has a value from 1 to 3.

[0067] - cce-REG-MappingType: Indicates the CCE-to-REG mapping type. Interleaved type and non-interleaved type are supported.

[0068] - precoderGranularity: Indicates the precoder granularity in the frequency domain.

[0069] - tci-StateSPDCCH: Indicates information (e.g., TCI-StateID) that indicates the TCI (Transmission Configuration Indication) state for the PDCCH. The TCI state is used to provide the QCL (Quasi-Co-Location) relationship between the DL RS within the RS set (TCI-state) and the PDCCH DMRS ports.

[0070] - tci-PresentInDCI: Indicates whether the TCI field is included in the DCI.

[0071] - pdcch-DMRS-ScramblingID: Indicates information used for initializing the PDCCH DMRS scrambling sequence.

[0072] For PDCCH reception, the terminal monitors a set of PDCCH candidates in the CORESET (e.g., blind decoding). A PDCCH candidate indicates a CCE that the terminal monitors for PDCCH reception / detection. PDCCH monitoring is performed on one or more CORESETs on the active DL BWP on each activated cell where PDCCH monitoring is configured. The set of PDCCH candidates that the terminal monitors is defined as the PDCCH search space (Search Space, SS) set. The SS set is either the common search space (Common Search Space, CSS) set or the UE-specific search space (USS) set.

[0073] Table 6 illustrates the PDCCH search space.

[0074]

Table 6

[0075] The SS set is configured by system information (e.g., MIB) or UE-specific upper layer (e.g., RRC) signaling. Each DL BWP of the serving cell is configured with up to S (e.g., 10) SS sets. For example, the following parameters / information are provided (by the RRC information element (IE) SearchSpace) for each SS set. Each SS set is associated with one CORESET, and each CORESET configuration is associated with one or more SS sets.

[0076] - searchSpaceId: Indicates the ID of the SS set.

[0077] - controlResourceSetId: Indicates the CORESET associated with the SS set.

[0078] - monitoringSlotPeriodicityAndOffset: Indicates the PDCCH monitoring periodicity interval (in slots) and the PDCCH monitoring interval offset (in slots).

[0079] - monitoringSymbolsWithinSlot: Indicates the first OFDMA symbol for PDCCH monitoring within the slot where PDCCH monitoring is configured. It is indicated via a bitmap, where each bit corresponds to an OFDMA symbol within the slot. The MSB of the bitmap corresponds to the first OFDM symbol within the slot. The OFDM symbol corresponding to the bit with a value of 1 corresponds to the first symbol of the CORESET within the slot.

[0080] - nrofCandidates: Indicates the number of PDCCH candidates (e.g., any one value of 0, 1, 2, 3, 4, 5, 6, 8) for each AL = {1, 2, 4, 8, 16}.

[0081] - searchSpaceType: Indicates whether the SS type is CSS or USS.

[0082] - DCI format: Indicates the DCI format of the PDCCH candidate.

[0083] Based on the CORESET / SS set configuration, the terminal can monitor PDCCH candidates in one or more SS sets within a slot. The opportunity (e.g., time / frequency resource) to monitor PDCCH candidates is defined as the PDCCH (monitoring) opportunity. One or more PDCCH (monitoring) opportunities are configured within a slot.

[0084] In the present invention, a scheduling cell means a cell where a PDCCH is transmitted or a cell where a terminal performs PDCCH monitoring, and a scheduled cell means a cell to which PUSCH / PDSCH resources are assigned / are to be assigned by DCI carried by the PDCCH. When cross-carrier scheduling is set for a serving cell, it is possible to set for the terminal which cell signals downlink assignments and uplink grants for the serving cell, that is, which cell is the scheduling cell for the serving cell. The DCI including resource allocation information for PUSCH / PDSCH includes information regarding which cell the resource allocation information is for, that is, which cell is the cell scheduled by the DCI. The serving cell where the PDCCH is transmitted can also become the cell it has scheduled itself.

[0085] 1. Control Channel Monitoring in High Frequency Band

[0086] The above-described content can be applied in combination with the method proposed in the present invention described below, or is supplemented to clarify the technical features of the method proposed in the present invention.

[0087] Moreover, the method described below can be similarly applied to the aforementioned NR system (licensed band) or shared spectrum, and it goes without saying that it can be modified or substituted according to the terms, expressions, structures, etc. defined in each system so that the technical idea proposed in the present invention can also be embodied in the corresponding system.

[0088] The NR system supports a number of new numerologies (or subcarrier spacing, SCS) to support various 5G services. For example, when the SCS is 15 kHz, it supports a wide area in the traditional cellular band. When the SCS is 30 kHz / 60 kHz, it supports dense-urban areas, lower latency, and a wider carrier bandwidth. When the SCS is 60 kHz or higher, it supports a band above 24.25 GHz. The NR frequency bands up to Release 16 are defined in two types (FR1, FR2) of frequency ranges and are configured as shown in Table 3. Also, in the future, discussions are underway to support the NR system in frequency bands above those defined by FR1 / FR2 (for example, 52.6 GHz to 71 GHz).

[0089] A frequency band higher than the FR1 and FR2 bands (for example, the 52.6 GHz to 114.25 GHz band, particularly the 52.6 GHz to 71 GHz band) is referred to as FR2-2. The waveforms, SCS, CP lengths, timing, etc. defined for FR1 and FR2 in the conventional NR system do not necessarily need to be applied to FR2-2.

[0090] In the FR2-2 band, for the operation of NR, SCSs of 120 kHz, 480 kHz, and 960 kHz are used. In the case of 480 kHz and 960 kHz SCSs, the length of the OFDM symbol becomes shorter compared to 120 kHz. For example, the OFDM symbol of 480 kHz is 1 / 4 times the length of the OFDM symbol of 120 kHz, and the OFDM symbol of 960 kHz is 1 / 8 times the length of the OFDM symbol of 120 kHz. For the short-length slots to which 480 kHz and 960 kHz are applied, if the operation of PDCCH monitoring is performed in all slots, it will impose a burden on the terminal such as power consumption. Therefore, when 480 kHz and / or 960 kHz SCSs are set, multi-slot PDCCH monitoring is introduced.

[0091] Multi-slot PDCCH monitoring means an operation of performing PDCCH monitoring by defining BD (Blind decoding) / CCE (control channel element) limits based on and / or in units of a plurality of consecutive slots. In the conventional NR rel-15, the BD / CCE limit is defined in units of one slot, and in NR rel-16, the BD / CCE limit is defined in units of a span confined within one slot. A span means a PDCCH monitoring unit consisting of consecutive symbols.

[0092] Hereinafter, the PDCCH monitoring performed in units of slots is referred to as per-slot monitoring, the PDCCH monitoring performed in units of spans is referred to as per-span monitoring, and the PDCCH monitoring performed in units of slot-groups is referred to as per-X monitoring. Hereinafter, in terms of terms related to multi-slot (PDCCH) monitoring (i.e., per-X monitoring), all of "slot-group size", "X", and "Xs" can refer to the time unit of per-X monitoring.

[0093] The BD limit means "Maximum number of monitored PDCCH candidates for a DL BWP with SCS configuration for a single serving cell" in the 3GPP standard, and the CCE limit means "Maximum number of non-overlapped CCEs for a DL BWP with SCS configuration for a single serving cell" in the 3GPP standard.

[0094] Multiple consecutive slots serving as the basis for multi-slot PDCCH monitoring are referred to as slot-groups. A slot-group consists of X consecutive slots, and the BD / CCE limit is defined in units of slot-groups. For example, for 480 kHz SCS, the BD / CCE limit is defined for each slot-group consisting of X = 4 slots. Also, Y consecutive slots are defined within a slot-group. There may be a type of SS set (search space sets) that is restricted such that PDCCH monitoring is performed only in Y slots. On the other hand, in the per-X monitoring operation, some parameters of the SS set configuration (e.g., periodicity, offset, duration) need to be set in units of X (by the base station to the terminal). For example, the period (periodicity) is set with a value per slot in per-slot monitoring, but is set in units of X slots in per-X monitoring. As an example, when X = 8 is set in a cell using 960 kHz SCS, the period value for per-X monitoring consists only of multiples of 8.

[0095] In per-X monitoring that operates based on different Xs from each other (or when the terminal reports that it supports multiple Xs), the base station can explicitly instruct the terminal about the X value for the cell and / or SCS via another RRC signaling or the like. In the absence of another instruction or before RRC signaling, the terminal determines and / or derives the X actually used for SS set configuration among the Xs reported to the base station based on the value of the SS set configuration, and performs per-X monitoring operations.

[0096] On the other hand, a terminal (e.g., UE) with multi-cell operation (e.g., carrier aggregation (CA)) configured monitors PDCCH for multiple cells. At this time, different SCSs may be configured for each cell. When per-X monitoring is configured, per-X monitoring may operate based on different X values for each cell (even with the same SCS). Therefore, it is necessary to instruct the terminal about the X value for each cell. Alternatively, a reference X for which per-X monitoring can operate is required for all cells with different X values configured.

[0097] Hereinafter, a method for determining the reference X used for SS set configuration in a situation where different X values are reported is proposed. Also, a configuration method for SS set group switching introduced in Rel-16 to operate for multiple Xs (multi-cell situation) as described above is proposed.

[0098] In the Rel-15 / 16 NR operation, the SS set configuration for per-slot monitoring and per-span monitoring is performed by signaling to the terminal via relevant RRC parameters the information regarding the period of PDCCH monitoring, the offset represented in slot units from the frame boundary, and the duration (Number of consecutive slots that a SearchSpace lasts in every occasion, i.e., upon every period as given in the periodicityAndOffset) indicating the number of slots in a period during which the SS set exists. The terminal determines the PDCCH monitoring occasion from such a period, offset, duration, and monitoring pattern within a slot.

[0099] On the other hand, per-X monitoring performs PDCCH monitoring in units of slot-groups consisting of X slots. Depending on the SS set type, PDCCH monitoring is performed only in Y slots within a slot-group for some SS sets. In slots among the X slots that are not Y slots, some SS sets may not be monitored depending on the SS set type. Therefore, SS set configuration parameters such as the period for determining the PDCCH MO (monitoring occasion) position need to be performed in units of X slots. X that can be supported may be different for each terminal, and the terminal can report one or more supported X values to the base station. The base station configures the SS set based on one of the reported X values and transmits the configuration information to the terminal via relevant RRC signaling.

[0100] The method in which SS set configuration parameters (e.g., period, offset, and / or interval) are set in units of X has various forms. For example, new RRC parameters with values in units of X are defined instead of the conventional RRC parameters with values in units of 1 slot. Also, even if the base station transmits RRC parameter values in units of 1 slot, the terminal applies a value obtained by multiplying the received RRC parameter value by X for each SCS (and using X reported or determined by the terminal). Further, among the RRC parameters with conventional 1-slot unit values, it is also possible to set only the values that are multiples of X for each SCS (and reported or determined by the terminal). The X-unit setting of the SS set configuration shown in the proposed method described below can be understood to include such setting methods.

[0101] The SS set configuration for the per-X monitoring operation needs to be performed in units of X slots. Depending on the SS set type, the MOs of some SS sets (for convenience, referred to as Group 2 SS) can be located in any of the slots of a slot-group consisting of X slots (i.e., a slot-group of size X). The MOs of some other SS sets (for convenience, referred to as Group 1 SS) can be located only within specific Y slots within the slot-group. For example, Group 1 SS includes Type 1 CSS with dedicated RRC configuration and type 3 CSS, and UE specific SS. Group 2 SS may be referred to as Type 1 CSS without dedicated RRC configuration and type 0, 0A, and 2 CSS.

[0102] Hereinafter, the SS set configuration method for per-X monitoring (operating in a multi-cell situation) will be described separately for Group 1 SS and Group 2 SS.

[0103] (Proposal 1) For the per-X monitoring operation, when the terminal reports multiple X values (as being supportable), the settings for Group 1 SS (e.g., period, offset, interval) are set based on the minimum value among the reported X values, and the terminal determines the PDCCH MO based on this minimum X value.

[0104] To make the MO of Group 1 SS exist only within Y slots out of X slots, the SS set settings (e.g., period, offset, and / or interval) values for the said SS need to consist only of multiples of X. On the other hand, when the terminal reports multiple X values that it is supportable for per-X monitoring for a specific SCS (or when reporting additional optional X values in addition to the mandatorily supported X), the base station determines the reference X for performing the SS set settings in units of X, and the terminal also needs to determine the MO based on the same X.

[0105] For example, for per-X monitoring operating at 960 kHz SCS, when the terminal reports that it is supportable for X = 8 and X = 4, the MO set based on X = 4 exists every 4 slots (e.g., the period is a multiple of 4), and the MO set based on X = 8 exists every 8 slots (e.g., the period is a multiple of 8). Therefore, the SS set settings need to be set based on X = 4, which corresponds to the greatest common divisor of the two X values, and the terminal determines the MO assuming X = 4. If all the X values reported by the terminal are in the form of powers of 2, since the smaller value is always a divisor of the larger value, the SS set settings are performed based on the minimum value among the reported X values. For the per-X monitoring operation where different X values are reported, the SS set settings for Group 1 SS are set based on the minimum value among the X values reported by the terminal. Also, the terminal determines the MO assuming that the SS settings (e.g., period, offset, interval) are performed based on this minimum X value.

[0106] Furthermore, the terminal implicitly or explicitly receives from the base station (via RRC or DCI) an X value that serves as a reference for the SS set configuration (period, offset, and / or interval) for the per-X monitoring operation for multiple cells. The terminal recognizes that the SS set is configured according to the indicated X value and determines the MO accordingly. For example, the terminal determines the available X values within the BWP based on all the configured SS sets within the BWP. In some embodiments, the minimum X value may be the default value (usable when not indicated by the base station).

[0107] (Proposal 1a) The configuration (e.g., period, offset, and / or interval) for group 1 SS for the per-X monitoring operation is set based on the minimum value among the X values that can be supported in the per-X monitoring operation for each SCS, and the terminal determines the PDCCH MO based on this minimum X value.

[0108] To make the MO of group 1 SS exist only in the Y slots within the X slots, the SS set configuration (e.g., period, offset, and / or interval) values for the SS must consist only of multiples of X. On the other hand, the X that can be supported for the per-X monitoring operation may be predefined for each SCS. For example, the per-X monitoring operation for 960 kHz is defined and / or configured based on X = 8 and / or X = 4, and the per-X monitoring operation for 480 kHz is defined and / or configured based on X = 4 and / or X = 2. The terminal reports to the base station the X that it prefers for the per-X monitoring operation for each SCS. In some embodiments of the present invention, there may be multiple X values for each SCS.

[0109] The SS set configuration is set and / or defined based on the minimum value among a plurality of X values. In other words, regardless of the X reported by the terminal to the base station, the SS set configuration is set and / or defined based on the minimum value of X (or (X, Y)) defined for the corresponding SCS in the relevant NR specification.

[0110] For example, when X = 8, X = 4 (or (X, Y) combinations including X = 8 or X = 4) are defined in the specification for per-X monitoring for 960 kHz SCS, even if the terminal reports that it supports X = 8 and does not report that it supports X = 4, the base station can perform the SS set configuration based on X = 4. When the SS set configuration is performed based on X = 4, the SS set configuration parameters such as period, offset, and interval are set and / or indicated by one of the multiples of 4. Or, when the SS set configuration is performed based on X = 4, the base station defines a value set of parameters such as period, offset, and interval by values consisting of multiples of 4, and sets and / or indicates one of these values to the terminal.

[0111] As another example, when X = 8, X = 4 (or (X, Y) combinations including X = 8 or X = 4) are defined in the specification for per-X monitoring for 960 kHz SCS, in a situation where X = 8 is a mandatory support element that the terminal must support, and X = 4 is an optional support element that some terminals may support, even if the terminal does not report that it supports the optional support element X = 4, since X = 4 is a value for which the operations defined in the specification are possible for the corresponding SCS, the SS set configuration (such as period, offset, and / or interval, etc.) can be performed based on X = 4.

[0112] For example, as follows, when (X, Y) for per-X monitoring is defined for 480 / 960 kHz

[0113]

Table 7

[0114] The SS set configuration is performed based on X = 4 for 480 kHz SCS and is also performed based on X = 4 for 960 kHz SCS. If the (X, Y) combination (2, 1) is added to the (X, Y) combinations selectively assisted for 480 kHz, the SS set configuration for 480 kHz is performed based on X = 2.

[0115] Furthermore, for the per-X monitoring operation for multiple cells, similar to Proposal 1a (instead of performing the SS set configuration based on the minimum value among the reported X values as in (Proposal 2) to be described later), regardless of whether there is a report for a specific X value of the terminal and / or regardless of the essential / selective assisted X, the SS set configuration is performed based on the minimum value among the X values supported by the per-X monitoring for each SCS. When the SS set configuration is performed based on the minimum value among the X values supported by the SS set configuration, the parameter of the SS set configuration is set by one of the multiple values of the minimum value of X. Alternatively, the base station sets and / or instructs the terminal to select one of the value sets consisting of the multiple values of the minimum value of X.

[0116] Although it has been described that the proposed content is applied to Group 1 SS, the SS set type is not limited to Group 1 SS. For example, the proposal may be applied only to Type-3 CSS set and / or UE specific SS.

[0117] (Proposal 2) For the per-X monitoring operation (for multiple cells), when X is different for each cell, the configuration (period, offset, and / or interval) for Group 1 SS is set based on the minimum value among the X values for each cell, and the terminal determines the PDCCH MO based on this minimum X value.

[0118] When per-X monitoring (for multiple cells) is configured for a UE, X may be different for each cell. For example, for two cells configured with 960 kHz SCS, if X = 4 is configured for cell #0 and X = 8 is configured for cell #1, the MO for cell #0 exists every 4 slots (the period is a multiple of 4), and the MO for cell #1 exists every 8 slots (the period is a multiple of 8). Therefore, for the UE to monitor both cell #0 and cell #1, it needs to operate assuming an MO with X = 4 corresponding to the greatest common divisor (or the minimum value) of the two X values. That is, for multi-cell operation with different X values, the SS set configuration for group 1 SS for per-X monitoring operation is configured based on the minimum value among the X values for each cell. Also, the UE determines the MO assuming that the SS configuration (such as period, offset, and / or interval) is performed based on the minimum value among the X values.

[0119] Furthermore, the UE may be indicated from the base station (via RRC or DCI) an X value that serves as a reference for the SS set configuration (all or part of the period, offset, interval) for per-X monitoring operation for multiple cells. For example, the X value configured for each cell may be provided to the UE explicitly, or may be provided to the UE implicitly via the search space configuration for the cell (or BWP). The UE recognizes that the SS set configuration is performed according to the indicated X value (i.e., the configured X value), and determines the MO accordingly. In this case, the minimum value among these X values uses the base value (which can be used when not indicated from the base station).

[0120] The proposed method is not limited to when per-X monitoring operates on multiple cells. That is, the proposed method is equally applicable to per-X monitoring for a single cell. Also, the proposed method described above is not limited to the case where all Xs are different for each cell even when per-X monitoring operates on multiple cells. That is, when all Xs are the same for each cell, when all Xs are different for each cell, when Xs for some cells are the same and Xs for some other cells are different, etc., it is similarly applicable. Those skilled in the art will fully understand that some expressions of the proposed method described above do not necessarily mean only the situations limited by the expressions described above.

[0121] (Proposal 3) When Xs are different from each other for each cell with respect to the per-X monitoring operation (for multiple cells), the settings (period, offset, and / or interval) for Group 2 SS are set based on X = 1 (i.e., in slot units) or the minimum value among the X values for each cell, and the terminal determines the PDCCH MO based on X = 1 or the minimum value among the X values for each cell.

[0122] Group 2 SS corresponds to an SS set type that is used when only cell-specific RRC settings (for any terminal) are set without dedicated RRC settings, or an SS set type that is commonly set for multiple terminal groups. Thus, when the parameter values of the SS set settings (e.g., period, offset, and / or interval) for per-X monitoring for multiple cells are set based on a specific X value for the SS set belonging to Group 2 SS, terminals that do not support that specific X value may not be able to accurately and completely determine the MO position without omission. As a method to solve such a problem, for Group 2 SS, the SS set settings are performed using one of the following three methods. The following methods may be applied to all of the SS set types belonging to Group 2 SS, or some methods may be applied only to a specific SS set type.

[0123] (Method 3-1) An SS set is configured (e.g., period, offset, and / or interval) based on X = 1, and the terminal determines the MO assuming that the SS set is configured based on X = 1. Here, the meaning of configuring based on X = 1 can be understood as performing SS set configuration in slot units, similar to conventional per-slot monitoring.

[0124] (Method 3-2) An SS set is configured (e.g., period, offset, and / or interval) based on the minimum X value for which a per-X monitoring operation is configured for a specific SCS. The terminal determines the MO assuming that the SS set for the per-X monitoring operation for that specific SCS is configured based on the minimum X value for which the per-X monitoring operation is configured for the specific SCS. For example, for per-X monitoring operating at 960 kHz SCS, if the X values for each cell are only X = 8 or X = 4, the SS set configuration for group 2 SS in per-X monitoring for multiple cells is performed based on X = 4, and the terminal determines the MO position assuming this.

[0125] (Method 3-3) For an SS set type commonly configured for multiple terminal groups, an SS set is configured (e.g., period, offset, and / or interval) based on the minimum value among all X values that can be reported by the terminals included in the terminal group. For example, if the minimum value among the X values reported by terminal #1 for a specific SCS of a specific cell is 4 and the minimum value among the X values reported by terminal #2 for the same specific SCS of the same specific cell is 8, the SS set configuration for the specific SCS of the specific cell is performed based on 4. The terminal determines the MO assuming that the SS set for the per-X monitoring operation for the specific SCS is configured based on the minimum value among the reportable X values.

[0126] The proposed method is not limited to when per-X monitoring operates on multiple cells. That is, the proposed method is equally applicable to per-X monitoring for a single cell. Also, the above-described proposed method is not limited to the case where all Xs are different for each cell even when per-X monitoring operates on multiple cells. That is, it is equally applicable to the case where all Xs are the same for each cell, the case where all Xs are different for each cell, the case where Xs for some cells are the same and Xs for some other cells are different, etc. Those skilled in the art will fully understand that some expressions of the above-described proposed method do not necessarily mean a situation limited by the above-described expressions.

[0127] (Proposal 4) When multiple X values are available for a cell, or when X values are different for each cell in a multi-cell situation, SS set group switching is performed at the slot-group boundary corresponding to the maximum X. Here, cells having different Xs from each other may mean cells belonging to the same cell group for SSSG switching.

[0128] SSSG (search space set group) switching is a feature introduced in rel-16 NR-U. When a group including a specific (single or multiple) SS set configuration is predefined (different SS set configurations may be performed for each group), it is a method for a terminal to vary the operation period of PDCCH monitoring, etc., according to the ID (or index) of SSSG. In some scenarios (e.g., NR rel-16), SSSG switching is applied in type-3 CSS sets and USS.

[0129] For example, referring to 3GPP TS 38.213 Rel-16, the terminal is provided by the base station with a group index for each respective type-3 CSS set or USS set in the searchSpaceGroupIdList of RRC parameters for PDCCH monitoring on the serving cell. This RRC parameter searchSpaceGroupIdList is included in the RRC configuration (e.g., IE SearchSpace) that defines how and where to search for PDCCH candidates and is provided to the terminal. This RRC parameter searchSpaceGroupIdList is a list of search space group IDs related to the search space defined by the IE SearchSpace. For example, the network sets two search space groups with search space group IDs of 0 or 1, or sets three search space groups with search space group IDs of 0, 1, or 2. One search space set belongs to one SSSG or multiple SSSGs. If one search space set belongs to both the SSSG before SSSG switching and the SSSG after SSSG switching, the search space set continues to be used for PDCCH monitoring even when SSSG switching occurs. If the searchSpaceGroupIdList is not provided to the terminal for a search space set, SSSG switching is not applied to PDCCH monitoring by the search space set. When the terminal is provided by the base station with the RRC parameter cellGroupsForSwitchList that indicates one or more serving cell groups, SSSG switching is applied to all serving cells within each group; otherwise, SSSG switching is applied only to the serving cells for which the searchSpaceGroupIdList is provided to the terminal.Here, the RRC parameter cellGroupsForSwitchList is a list of serving cells bundled for the purpose of SSSG switching. The serving cells belong to only one cellGroupForSwitch, and the network sets the same list for all BWPs of the serving cells within the same cellGroupForSwitch. When the searchSpaceGroupIdList is provided to the terminal, the terminal resets PDCCH monitoring according to the search space set with group index 0 if the searchSpaceGroupIdList is provided. In some embodiments of the present invention, the time value or the number of symbols required from after the SSSG switching is notified or triggered until the SSSG switching is performed is provided to the terminal by the base station, or the minimum number of symbols P. switch is predefined for each SCS setting. For example, the number of symbols P is provided by the RRC parameter searchSpaceSwitchDelay from the base station to the terminal. switch The minimum value of P is provided as shown in the following table for terminal processing capabilities 1 and 2 and SCS settings u = 0, 1, 2, for example. switch For example, for terminal processing capabilities 1 and 2 and SCS settings u = 0, 1, 2, the minimum value of P is provided as follows in the table.

[0130]

Table 8

[0131] The terminal receives the timer value from the base station by means of the RRC parameter searchSpaceSwitchTimer for the serving cell for which the searchSpaceGroupIdList is provided, or, if provided, for the set of serving cells provided by the cellGroupsForSwitchList. The base station sets the same searchSpaceSwitchTimer value for all serving cells belonging to the same cellGroupForSwitch. The terminal decrements the timer value by 1 after each slot based on the reference SCS setting, where the reference SCS setting is the minimum SCS setting u among all the configured DL BWPs within the serving cell or the set of serving cells. When the position of the search space set group (SSSG) switching flag for the serving cell within DCI format 2_0 (or for the set of serving cells provided by the cellGroupsForSwitchList) is provided to the terminal by the base station by means of the RRC parameter SearchSpaceSwitchTrigger:

[0132] > If the terminal detects DCI format 2_0 and the value of the SSSG switching flag within DCI format 2_0 is 0, the terminal starts monitoring the PDCCH according to the search space set with group index 0 for the serving cell in the first slot after at least P switch symbols have passed after the last symbol of the PDCCH with DCI format 2_0, and aborts monitoring the PDCCH according to the search space set with group index 1;

[0133] > If the terminal detects DCI format 2_0 and the value of the SSSG switching flag within DCI format 2_0 is 1, the terminal starts monitoring the PDCCH according to the search space set with group index 0 for the serving cell in the first slot after at least P switchAt the first slot after the number of symbols has passed, start monitoring the PDCCH for the serving cell according to the search space set with group index 1, stop monitoring the PDCCH according to the search space set with group index 0, and the terminal sets the timer value according to the value provided by searchSpaceSwitchTimer;

[0134] > When the terminal monitors the PDCCH for the serving cell according to the search space set with group index 1, the terminal, after the slot in which the timer expires, or when indicated by DCI format 2_0, after the last symbol of the remaining channel occupancy duration for the serving cell, at least P switch At the start of the first slot after the number of symbols has passed, start monitoring the PDCCH for the serving cell according to the search space set with group index 0, and stop monitoring the PDCCH according to the search space set with group index 1.

[0135] For each serving cell within a set of serving cells, the position of the SSSG switching flag field in DCI format 2_0 is provided by the base station to the terminal via the RRC parameter SearchSpaceSwitchTrigger, and the SSSG switching flag indicates a group from the set of search spaces for PDCCH monitoring for scheduling for that serving cell or, if provided by the RRC parameter cellGroupsForSwitchList, for the set of serving cells. Each SearchSpaceSwitchTrigger value provides the position within that DCI format of a bit field indicating the SSSG switching flag for the serving cell or, if cellGroupsForSwitchList is configured, for the group of serving cells (e.g., the set of serving cells belonging to the same cellGroupForSwitch). In some implementations, for each serving cell within a set of serving cells, the position of the channel occupancy (CO) period field in DCI format 2_0 is provided by the base station to the terminal via the RRC parameter co-DurationsPerCell, and the CO period field indicates the remaining CO period for the serving cell starting from the first symbol of the slot in which the terminal detected DCI format 2_0 by providing a value from the RRC parameter co-DurationList. The CO period field is max{ceil( log2 (COdurationListSize)), 1} bits, where COdurationListSize is the number of values provided by co-DurationList.

[0136] When SearchSpaceSwitchTrigger is not provided to the terminal for a serving cell:

[0137] > When the terminal detects a DCI format by monitoring the PDCCH according to the search space set of group index 0, the terminal is at least P after the last symbol of the PDCCH having the DCI format switch In the first slot after the P symbols have passed, for the serving cell, start monitoring the PDCCH according to the search space set having group index 1, stop monitoring the PDCCH according to the search space set having group index 0, and when the terminal detects a DCI format by monitoring the PDCCH in any search space set, the terminal sets the timer value according to the value provided by the searchSpaceSwitchTimer;

[0138] > When the terminal monitors the PDCCH for the serving cell according to the search space set of group index 1, the terminal is at the start of the first slot after P symbols have passed after the slot in which the timer expires, or when the search space set for monitoring the PDCCH for detecting DCI format 2_0 is provided, and when instructed by DCI format 2_0, after the last symbol of the remaining channel occupancy period for the serving cell, start monitoring the PDCCH for the serving cell according to the search space set having group index 1, stop monitoring the PDCCH according to the search space set having group index 0, and when the terminal detects a DCI format by monitoring the PDCCH in any search space set, the terminal sets the timer value according to the value provided by the searchSpaceSwitchTimer. switch In the first slot after the P symbols have passed, for the serving cell, start monitoring the PDCCH according to the search space set having group index 1, stop monitoring the PDCCH according to the search space set having group index 0, and when the terminal detects a DCI format by monitoring the PDCCH in any search space set, the terminal sets the timer value according to the value provided by the searchSpaceSwitchTimer.

[0139] According to 3GPP TS 38.213 Rel-16, for a serving cell with a provided searchSpaceGroupIdList, or for a set of serving cells when a cellGroupsForSwitchList is provided, the slots and symbols within the slots for starting or stopping PDCCH monitoring according to a search space set are determined based on the minimum SCS setting u among all the configured DL BWPs in the serving cell or in the set of serving cells, and in the serving cell where the terminal receives the DCI format 2_0 used to notify the start or stop of PDCCH monitoring by the search space set, if any.

[0140] As described above, switching between different SSSGs for per-slot monitoring is performed at slot boundaries. For example, after an SSSG switching is notified or triggered, PDCCH monitoring is performed according to the SSSG that is changed starting from the first slot after the above symbols have passed. However, in the case of per-X monitoring, if the SS set configuration is changed in the middle of a slot-group, the complexity of the terminal increases. To avoid this, the switching between SSSGs needs to be performed at slot-group boundaries. switch On the other hand, when multi-cell operation is configured for the terminal, X for per-X monitoring may be different for each cell. At this time, the timing of SSSG switching is determined by two different methods. In the methods described later, cells with different Xs from each other mean cells belonging to the same cell group for SSSG switching.

[0141] Figures 4 and 5 illustrate search space set group switching according to some embodiments of the present invention.

[0142]

[0143] ​(Method 4-1) When the X values are different for each cell, SSSG switching is performed at the boundaries of different Xs (i.e., slot-groups) for each cell. For example, for the case where cell♯0 has X = 4 and cell♯1 has X = 8, a situation can be considered where both in cell♯0 and cell♯1 are switched from SSSG♯0 to SSSG♯1 via one SSSG switching triggering. After both cell♯0 and cell♯1 are triggered for switching, P switch After the symbol has passed, PDCCH monitoring by SSSG♯1 can be started at the first slot-group boundary. However, since the slot-group of cell♯0 consists of 4 slots and the slot-group of cell♯1 consists of 8 slots, as shown in FIG. 4, the actual time points of switching to SSSG♯1 may be different from each other.

[0144] (Method 4-2) Even when the X values are different for each cell, all the cells monitored by the terminal perform SSSG switching at the X boundary (i.e., the slot-group boundary) with respect to the reference X. The reference X may be the maximum X among the X values that the terminal can support (or among the X values of the cells monitored by the terminal). For example, in the situation of cell♯0 and cell♯1 illustrated in Method 4-1, when SSSG switching is performed with X = 8 of cell♯1 as the reference, cell♯0 also changes to SSSG♯1 at the slot-group boundary of cell♯1 (see Fig. 4). As another example, referring to Fig. 5, when multiple X values are available for a single SCS or a single cell, SSSG switching is performed at the slot-group boundary with the maximum X value among the multiple available X values as the reference. According to SSSG Method 4-2, SSSG switching is performed at the same time for all the cells (belonging to CellGroupForSwitch) monitored by the terminal and for all the search space sets for which SSSG switching is set. In other words, according to some embodiments of the present invention, even when multiple-slot PDCCH monitoring (i.e., per-X monitoring is performed) cells are set for the terminal, when a search space set for a cell and a cell group are set for SSSG switching, SSSG switching is performed at the same time for all the cells in the cell group. Thereby, the base station and the terminal can more efficiently use the unlicensed spectrum, and the implementation of the terminal can be simplified. The effects obtained by making the SSSG switching times the same for a search space set or for multiple cells are, for example, as follows. During the CO interval (channel occupancy duration) from the unlicensed band (Unlicensed band, or shared spectrum), SSSG switching is used before and after the CO interval to reduce the frequency of PDCCH monitoring.In the transmission process using multiple cells like CA, the CO intervals for multiple cells are set to end simultaneously. In this case, by matching the SSSG switching points between search space sets or between cells, there is an advantage that the operation of the terminal can be simplified.

[0145] In some embodiments of the present invention, P switchIt may be a value provided by the base station to the terminal or a value predefined by the SCS setting u. In some embodiments of the present invention, for a serving cell in which the SSSG flag field in DCI format 2_0 is provided by searchSpaceSwitchTrigger, the terminal determines that SSSG switching is triggered when: i) in the last symbol of the PDCCH having DCI format 2_0 when detecting a DCI format 2_0 with the value of the SSSG switching flag field being 0 or 1; ii) in the slot where the timer expires according to the timer value provided by searchSpaceSwitchTimer when monitoring the PDCCH for the serving cell according to the search space set of group index 1, or when indicated by DCI format 2_0, in the last symbol of the remaining CO period for the serving cell. In some embodiments of the present invention, when searchSpaceSwitchTrigger is not provided for the serving cell, the terminal determines that SSSG switching is triggered when: i) in the last symbol of the PDCCH having the detected DCI format when monitoring the PDCCH according to the search space set having group index 0; ii) in the slot where the timer expires according to the timer value provided by searchSpaceSwitchTimer when monitoring the PDCCH for the serving cell according to the search space set having group index 1, or when the search space set for monitoring the PDCCH is provided for the terminal to detect DCI format 2_0, and when indicated by DCI format 2_0, in the last symbol of the remaining CO period for the serving cell. In some embodiments of the present invention, the terminal is at least P after the symbol or slot in which SSSG switching is triggered switchWhen SSSG switching is triggered at the start of the first slot of a slot-group after a symbol, PDCCH monitoring by the search space set of the monitored SSSG is aborted, and SSSG switching is performed to start PDCCH monitoring by the search space set of another SSSG.

[0146] Furthermore, it is also possible to flexibly change Method 4-1 and Method 4-2. That is, the base station instructs the terminal via high-layer signaling such as RRC whether the SSSG switching time point for each cell is at a different boundary of X for each cell or at the boundary of a reference X (e.g., maximum X). Alternatively, a 1-bit field is added to DCI format 2_0 used to notify SSSG switching, and information designating either Method 4-1 or Method 4-2 is transmitted via the added 1-bit field. As a result, when individual CO intervals are obtained for each beam, there is an advantage that the SSSG switching time point can be set individually for each beam. As another method, one of Method 4-1 and Method 4-2 may be pre-defined according to the SSSG switching trigger type. For example, when switching is notified or triggered by DCI 2_0 or the like, the switching time points of all cells are adjusted to the boundary of the maximum X, and when switching is triggered by the expiration of the SSSG switching timer, SSSG switching is performed at different X boundaries for each cell. Alternatively, when entering the CO interval in the operation of the unlicensed band (or shared spectrum), SSSG switching is performed for each cell at the X boundary of each cell, and when switching is triggered by the end of the CO interval, it is also possible to perform an operation to match the switching time points of all cells with the maximum X. As a result, unnecessary power consumption can be reduced during the CO interval, and when the CO interval ends, the complexity of the terminal operation can be reduced by having all cells perform SSSG switching at the same time point.

[0147] (Proposal 5) Method for Aligning SSSG Switching Boundaries of Cells Belonging to CellGroupForSwitch

[0148] (5-1) To align the SSSG switching boundaries of cells belonging to / included in CellGroupForSwitch, any one of the following methods is applied. Hereinafter, Xs has the same meaning as X in the aforementioned proposal.

[0149] >> Align based on the maximum Xs among all the configured BWPs for all cells within the same CellGroupForSwitch

[0150] >> Align based on the maximum Xs among all the active BWPs for all cells within the same CellGroupForSwitch

[0151] >> Align based on the maximum Xs among all the reported Xs values by the terminal

[0152] (5-2) When CellGroupForSwitch contains only one serving cell, or when CellGroupForSwitch is not configured (i.e., in the case of a single serving cell), even if the Xs values configured for each DL (or UL) BWP are different, the SSSG switching boundaries may be aligned based on the maximum Xs value (see Figure 5). For example, it is shown as follows.

[0153] >> Align based on the maximum Xs among all the configured / active BWPs or reported Xs values

[0154] In some embodiments, the cells collected by CellGroupForSwitch can be restricted to have the same Xs for each SCS (or only cells having the same Xs are set by CellGroupForSwitch). For example, a terminal (with 480 / 960 kHz set) does not have to expect that cells (or the BWPs of the cells) with the same SCS but different set Xs among the plurality of set cells are collected by the same CellGroupForSwitch.

[0155] In Proposal 5, the set Xs are the Xs values explicitly or implicitly provided by the base station to the terminal. For example, the base station may implicitly provide the terminal with an explicit Xs value for the cell (or BWP or SCS), or may implicitly provide the terminal with the Xs set for the cell (or BWP or SCS) by the search space setting. The terminal determines the Xs value set for the cell (or BWP or SCS) based on the explicitly provided Xs value or the Xs associated with the search space set set for the cell (or BWP or SCS).

[0156] Furthermore, as described above, the delay (or switching time) of SSSG switching of cells belonging to CellGroupForSwitch may be determined based on the SCS of all configured BWPs set in the terminal, or may be determined based on the SCS of all active BWPs among the BWPs set in the terminal. That is, when the SCSs set for the cells (or BWPs) included in CellGroupForSwitch are different, the cells belonging to CellGroupForSwitch are simultaneously SSSG-switched at the slot boundary of the SCS corresponding to the minimum value among the SCSs of each cell (i.e., the minimum value among the SCSs of the cells belonging to CellGroupForSwitch). At this time, as the SCS of each cell, the SCSs set for all configured BWPs are used, or the SCSs set for all active BWPs are used. For this purpose, an RRC setting or the like for setting / indicating / selecting one of the two criteria is introduced.

[0157] Furthermore, for the per-X monitoring operation, the terminal operates as follows. Alternatively, it is set (by the base station via RRC or the like) to operate as follows.

[0158] For a terminal for which per-X monitoring is set, for some CSSs (e.g., CSSs such as type 0 / OA), the terminal monitors over the entire slot-group of size X, and for some other CSSs (e.g., type 3 CSS) and / or terminal-specific SSs (i.e., USS), it is set to monitor only specific / partial Y slots within X slots. At this time, for a specific CSS type to be monitored in any slot of the slot-group of size X, for a terminal-specific RNTI (e.g., C-RNTI and / or MCS-C-RNTI and / or CS-RNTI), it is predefined to monitor only the Y slots, or is set (by the base station to the terminal via RRC or the like). Alternatively, the terminal may report to the base station that it is a terminal capable of / preferring to operate based on the terminal's capability report.

[0159] In some embodiments, the aforementioned "configured X", "configured X", "configured Xs", "indicated Xs", "configured slot-group size", or "indicated slot-group size" is determined based on the search space configuration provided by the base station to the terminal.

[0160] On the other hand, the content of the present invention is not limited to the transmission and reception of uplink and / or downlink signals. For example, the content of the present invention can also be used for direct communication between terminals. Also, the base station in the present invention is a concept that includes not only a Base Station but also a relay node. For example, the operation of the base station in the present invention may be performed by the base station (Base Station) or by the relay node.

[0161] Since an example of the aforementioned proposed method is also included as one of the implementation methods of the present invention, it is an obvious fact that it is regarded as a kind of proposed method. Also, the aforementioned proposed method may be implemented independently or by a combination (or merger) of some proposed methods. The information on the suitability of this proposed method (or the information on the rules of this proposed method) may be defined such that the base station notifies the terminal or the transmitting terminal notifies the receiving terminal via a predefined signal (e.g., a physical layer signal or a higher layer signal).

[0162] Embodiment

[0163] FIG. 6 and FIG. 7 are flowcharts of a signal transmission / reception method according to an embodiment of the present invention.

[0164] Referring to FIG. 6, some embodiments of the present invention are performed by executing instructions stored in a terminal, or in a memory within the terminal or in a device for the terminal, or by executing instructions or programs stored in a non-volatile storage medium. The operation by the terminal or the instructions / programs is to perform PDCCH monitoring according to a search space set of a first SSSG having a first group index for a serving cell or a serving cell set (for example, serving cells belonging to the same cellGroupForSwitch) (S601). During the execution of PDCCH monitoring according to the search space set of the first SSSG, the terminal recognizes that an SSSG switching has been notified or triggered according to some embodiments of the present invention. For example, the terminal or the operation detects a DCI format that notifies an SSSG switching for the serving cell or the serving cell set, or determines that the SSSG switching has been triggered based on the expiration of a timer related to the SSSG switching, or the end of the remaining CO period. The terminal determines a switching time point of the SSSG for the notified / triggered SSSG switching (S603). In some embodiments, the terminal or the operation determines the switching time point of the SSSG based on the slot-group size (hereinafter, Xs) for the serving cell or the serving cell set. At the switching time point of the SSSG, the terminal or the operation aborts PDCCH monitoring according to the search space set of the first SSSG and starts PDCCH monitoring according to a search space set of a second SSSG having a second group index different from the first group index (S605).

[0165] In some embodiments, in addition to the operations described with respect to FIG. 6, the operations described with reference to FIGS. 1 to 5 and / or one or more of the operations described in the above item 1 can be combined and performed.

[0166] Referring to FIG. 7, some embodiments of the present invention are performed by executing an instruction stored in a memory in a base station, or in an apparatus within or for a base station, or by executing an instruction or program stored in a non-volatile storage medium. The operation by the base station or the instruction / program is to perform PDCCH transmission according to a search space set of a first SSSG having a first group index for a serving cell or a serving cell set (for example, serving cells belonging to the same cellGroupForSwitch) (S701). During the execution of PDCCH transmission according to the search space set of the first SSSG, the base station or the operation notifies SSSG switching or recognizes that SSSG switching has been triggered according to some embodiments of the present invention. For example, the base station or the operation transmits a DCI format that triggers SSSG switching for the serving cell or the serving cell set, or determines that SSSG switching has been triggered based on the expiration of a timer related to SSSG switching or the end of the remaining CO period. The base station or the operation determines a time point for SSSG switching for the triggered SSSG switching (S703). In some embodiments, the base station or the operation determines the SSSG switching time point based on a slot-group size (hereinafter, Xs) for the serving cell or the serving cell set. The base station or the operation stops transmitting the PDCCH according to the search space set of the first SSSG at the SSSG switching time point, and starts transmitting the PDCCH according to a search space set of a second SSSG having a second group index different from the first group index (S705).

[0167] In some embodiments, a search space configuration including a first group index of a first SSSG and a second group index of a second SSSG is provided by the base station to the terminal.

[0168] In some embodiments, when per-X PDCCH monitoring is performed for a terminal or a base station, or an operation, with respect to a serving cell or a serving cell set, the SSSG switching time is determined based on the maximum Xs among the Xs values for the serving cell or the serving cell set.

[0169] In some embodiments, the SCS of the serving cell or the serving cell set for which per-X PDCCH monitoring is performed is 960 kHz. In some embodiments, the SCS of the serving cell or the serving cell set for which per-X PDCCH monitoring is performed is 480 kHz. In some embodiments, the SCS of the serving cell set for which per-X PDCCH monitoring is performed is 480 kHz and / or 960 kHz.

[0170] In some embodiments, a terminal or an operation receives a search space configuration for at least one serving cell (e.g., a serving cell or a serving cell set), the search space configuration includes a configuration regarding at least one search space set belonging to a first search space set group (SSSG) having at least a first group index, and a configuration regarding at least one search space set belonging to a second SSSG having a second group index. Based on the search space configuration, physical downlink control channel (PDCCH) monitoring is performed according to the search space set of the first SSSG for at least one serving cell, and SSSG switching is performed based on detecting a DCI format that notifies SSSG switching for at least one serving cell, or based on a timer related to SSSG switching expiring. In some embodiments, based on at least one serving cell including a serving cell having a 960 kHz subcarrier spacing, the SSSG switching is at least a predetermined number P from the last symbol of the PDCCH having the DCI format.switch At the beginning of the first slot of a slot-group of Xs slots after a symbol, including: i) stopping PDCCH monitoring according to a search space set of a first SSSG; and ii) starting PDCCH monitoring according to a search space set of a second SSSG, where the slot-groups of Xs slots are consecutive. In some implementations, based on at least one serving cell including a serving cell having a subcarrier spacing of 960 kHz, a terminal or operation determines a slot and a symbol within the slot to stop or start PDCCH monitoring for SSSG switching based on the maximum Xs value among Xs values (e.g., Xs values associated / set for at least one serving cell) for at least one serving cell.

[0171] In some embodiments, a base station or operation transmits search space configurations for at least one serving cell (e.g., a serving cell or a serving cell set), the search space configurations including configurations for at least one search space set belonging to a first search space set group (SSSG) having at least a first group index and configurations for at least one search space set belonging to a second SSSG having a second group index, and based on the search space configurations, transmits at least one physical downlink control channel (PDCCH) according to the search space set of the first SSSG for at least one serving cell, and performs SSSG switching based on transmitting a DCI format that notifies SSSG switching for at least one serving cell or based on a timer related to SSSG switching expiring. In some embodiments, based on at least one serving cell including a serving cell having a subcarrier spacing of 960 kHz, the SSSG switching includes, at the beginning of the first slot of a slot-group of an Xs slot at least P switch symbols after the last symbol of the PDCCH having the DCI format, i) stopping transmitting at least one PDCCH according to the search space set of the first SSSG and ii) starting to transmit at least one PDCCH according to the search space set of the second SSSG, where the slot-group of the Xs slot is consecutive. In some embodiments, based on at least one serving cell including a serving cell having a subcarrier spacing of 960 kHz, the base station or operation determines the slot and the symbol within the slot in which the SSSG switching is performed based on the maximum Xs value among Xs values (e.g., Xs values associated / set for at least one serving cell) for at least one serving cell.

[0172] In some embodiments, the switch cell group setting is provided to the terminal by the base station. When the switch cell group setting is provided, at least one serving cell is a serving cell set. Based on the switch cell group setting, the SSSG switching is performed for all serving cells within the serving cell set.

[0173] In some embodiments, the switch cell group setting is the radio resource control (RRC) parameter cellGroupForSwitch.

[0174] In some embodiments, information regarding a predetermined number P switch is provided to the terminal by the base station.

[0175] In some embodiments, the predetermined number P switch is predefined for a subcarrier spacing of 960 kHz and the processing capability of the terminal.

[0176] In some embodiments, each search space set within the first SSSG and the second SSSG is set based on one of the Xs values of the at least one serving cell for the Xs value.

[0177] In some embodiments, each of the Xs values for the at least one serving cell is related to the search space set configured for the at least one serving cell.

[0178] In some embodiments, information regarding the position of the SSSG flag field within the DCI format for the at least one serving cell is provided to the terminal by the base station.

[0179] In some embodiments, the DCI format is DCI format 2_0.

[0180] Example of Communication System to which the Present Invention is Applied

[0181] Without being limited thereto, the various descriptions, functions, procedures, proposals, methods, and / or flowcharts of the present invention disclosed herein can be applied to various fields that require wireless communication / connection (e.g., 5G) between devices.

[0182] The following will be described more specifically with reference to the drawings. In the following figures / descriptions, the same reference numerals exemplify the same or corresponding hardware blocks, software blocks, or functional blocks unless otherwise specifically mentioned.

[0183] FIG. 8 illustrates a communication system 1 to which the present invention is applied.

[0184] Referring to FIG. 8, the communication system 1 applied to the present invention includes a wireless device, a base station, and a network. Here, the wireless device means a device that communicates using a wireless connection technology (e.g., 5G NR, LTE), and is also referred to as a communication / wireless / 5G device. Without being limited thereto, the wireless devices include a robot 100a, vehicles 100b-1, 100b-2, an XR (Extended Reality) device 100c, a hand-held device 100d, home appliances 100e, IoT (Internet of Thing) devices 100f, and an AI server / device 400. For example, the vehicles include vehicles equipped with a wireless communication function, autonomous driving vehicles, vehicles capable of vehicle-to-vehicle communication, etc. Here, the vehicles include UAVs (Unmanned Aerial Vehicles) (e.g., drones). The XR device includes AR (Augmented Reality) / VR (Virtual Reality) / MR (Mixed Reality) devices, and is embodied in the form of an HMD (Head-Mounted Device), an HUD (Head-Up Display) provided in a vehicle, a TV, a smartphone, a computer, a wearable device, a home appliance device, a digital signboard, a vehicle, a robot, etc. The hand-held devices include smartphones, smart pads, wearable devices (e.g., smart watches, smart glasses), computers (e.g., notebook computers, etc.). The home appliances include TVs, refrigerators, washing machines, etc. The IoT devices include sensors, smart meters, etc. For example, the base station and the network are also embodied in the wireless device, and a specific wireless device 200a can also operate as a base station / network node for other wireless devices.

[0185] Wireless devices 100a to 100f are connected to network 300 via base station 200. AI (Artificial Intelligence) technology is applied to wireless devices 100a to 100f, and wireless devices 100a to 100f are connected to AI server 400 via network 300. Network 300 is configured using a 3G network, 4G (e.g., LTE) network, or 5G (e.g., NR) network, etc. Wireless devices 100a to 100f can communicate with each other via base station 200 / network 300, but can also communicate directly without going through the base station / network (e.g., sidelink communication). For example, vehicles 100b-1 and 100b-2 can communicate directly (e.g., V2V (Vehicle to Vehicle) / V2X (Vehicle to everything) communication). Also, IoT devices (e.g., sensors) can communicate directly with other IoT devices (e.g., sensors) or other wireless devices 100a to 100f.

[0186] Wireless communications / connections 150a, 150b, and 150c are performed between wireless devices 100a to 100f / base station 200 and between base station 200 / base station 200. Here, the wireless communications / connections are uplink / downlink communication 150a, sidelink communication 150b (or D2D communication), and communication between base stations 150c (e.g., performed by various wireless connection technologies such as relay and IAB (Integrated Access Backhaul) (e.g., 5G NR)). Through wireless communications / connections 150a, 150b, and 150c, wireless devices and base stations / wireless devices, and base stations and base stations can transmit / receive wireless signals to / from each other. For example, wireless communications / connections 150a, 150b, and 150c can transmit / receive signals via various physical channels. For this purpose, based on various proposals of the present invention, any one of the setting process of various configuration information for transmitting / receiving wireless signals, various signal processing processes (e.g., channel encoding / decoding, modulation / demodulation, resource mapping / demapping, etc.), and resource allocation process is performed.

[0187] Example of Wireless Device to which the Present Invention is Applied

[0188] FIG. 9 illustrates a wireless device applicable to the present invention.

[0189] Referring to FIG. 9, the first wireless device 100 and the second wireless device 200 transmit and receive wireless signals by various wireless connection technologies (e.g., LTE, NR). Here, {the first wireless device 100, the second wireless device 200} corresponds to {the wireless device 100x, the base station 200} and / or {the wireless device 100x, the wireless device 100x} in FIG. 8.

[0190] The first wireless device 100 includes one or more processors 102 and one or more memories 104, and further includes one or more transceivers 106 and / or one or more antennas 108. The processor 102 controls the memory 104 and / or the transceiver 106 and is configured to implement the descriptions, functions, procedures, proposals, methods, and / or flowcharts disclosed herein. For example, after the processor 102 processes the information in the memory 104 to generate a first information / signal, the transceiver 106 transmits a wireless signal including the first information / signal. Also, after the processor 102 receives a wireless signal including a second information / signal by the transceiver 106, the information obtained from the signal processing of the second information / signal is stored in the memory 104. The memory 104 is connected to the processor 102 and stores various information related to the operation of the processor 102. For example, the memory 104 performs some or all of the processes controlled by the processor 102, or stores software code including instructions for performing the descriptions, functions, procedures, proposals, methods, and / or flowcharts disclosed herein. Here, the processor 102 and the memory 104 are part of a communication modem / circuit / chip designed to implement wireless communication technologies (e.g., LTE, NR). The transceiver 106 is connected to the processor 102 and transmits and / or receives wireless signals by one or more antennas 108. The transceiver 106 includes a transmitter and / or a receiver. The transceiver 106 can also be used interchangeably with an RF (radio Frequency) unit. In the present invention, the wireless device can also mean a communication modem / circuit / chip.

[0191] The second wireless device 200 includes one or more processors 202 and one or more memories 204, and further includes one or more transceivers 206 and / or one or more antennas 208. The processor 202 controls the memory 204 and / or the transceiver 206, and is configured to implement the descriptions, functions, procedures, proposals, methods, and / or flowcharts disclosed herein. For example, after the processor 202 processes the information in the memory 204 to generate a third information / signal, the transceiver 206 transmits a wireless signal including the third information / signal. Also, after the processor 202 receives a wireless signal including a fourth information / signal by the transceiver 206, the processor 202 stores the information obtained from the signal processing of the fourth information / signal in the memory 204. The memory 204 is connected to the processor 202 and stores various information related to the operation of the processor 202. For example, the memory 204 performs some or all of the processes controlled by the processor 202, or stores software code including instructions for performing the descriptions, functions, procedures, proposals, methods, and / or flowcharts disclosed herein. Here, the processor 202 and the memory 204 are part of a communication modem / circuit / chip designed to implement wireless communication technologies (e.g., LTE, NR). The transceiver 206 is connected to the processor 202 and transmits and / or receives wireless signals through one or more antennas 208. The transceiver 206 includes a transmitter and / or a receiver. The transceiver 206 can also be used interchangeably with an RF unit. In the present invention, the wireless device can also mean a communication modem / circuit / chip.

[0192] The hardware elements of the wireless devices 100 and 200 will be described in more detail below. Although not limited thereto, one or more protocol layers are implemented by one or more processors 102 and 202. For example, one or more processors 102 and 202 implement one or more layers (e.g., functional layers such as PHY, MAC, RLC, PDCP, RRC, SDAP). One or more processors 102 and 202 generate one or more PDUs (Protocol Data Units) and / or one or more SDUs (Service Data Units) according to the descriptions, functions, procedures, proposals, methods, and / or flowcharts disclosed herein. One or more processors 102 and 202 generate messages, control information, data, or information according to the descriptions, functions, procedures, proposals, methods, and / or flowcharts disclosed herein. One or more processors 102 and 202 generate signals (e.g., baseband signals) including PDUs, SDUs, messages, control information, data, or information according to the functions, procedures, proposals, and / or methods disclosed herein and provide them to one or more transceivers 106 and 206. One or more processors 102 and 202 receive signals (e.g., baseband signals) from one or more transceivers 106 and 206 and can obtain PDUs, SDUs, messages, control information, data, or information according to the descriptions, functions, procedures, proposals, methods, and / or flowcharts disclosed herein.

[0193] One or more processors 102, 202 are also referred to as a controller, microcontroller, microprocessor, or microcomputer. One or more processors 102, 202 are implemented by hardware, firmware, software, or a combination thereof. As an example, one or more ASICs (Application Specific Integrated Circuits), one or more DSPs (Digital Signal Processors), one or more DSPDs (Digital Signal Processing Devices), one or more PLDs (Programmable Logic Devices), or one or more FPGAs (Field Programmable Gate Arrays) are included in one or more processors 102, 202. The descriptions, functions, procedures, proposals, methods, and / or flowcharts disclosed herein are implemented using firmware or software, and the firmware or software is implemented to include modules, procedures, functions, and the like. The firmware or software configured to perform the descriptions, functions, procedures, proposals, methods, and / or flowcharts disclosed herein is included in one or more processors 102, 202, or stored in one or more memories 104, 204 and driven by one or more processors 102, 202. The descriptions, functions, procedures, proposals, methods, and / or flowcharts disclosed herein are implemented using firmware or software in the form of code, instruction words, and / or sets of instruction words.

[0194] One or more memories 104, 204 are coupled to one or more processors 102, 202 and can store various forms of data, signals, messages, information, programs, codes, instructions, and / or commands. The one or more memories 104, 204 are constituted by a ROM, a RAM, an EPROM, a flash memory, a hard drive, a register, a cache memory, a computer-readable storage medium, and / or a combination thereof. The one or more memories 104, 204 are located inside and / or outside the one or more processors 102, 202. Also, the one or more memories 104, 204 are coupled to the one or more processors 102, 202 by various techniques such as wired or wireless connections.

[0195] One or more transceivers 106, 206 can transmit user data, control information, radio signals / channels, etc. mentioned in the methods and / or flowcharts herein to one or more other devices. One or more transceivers 106, 206 can receive user data, control information, radio signals / channels, etc. mentioned in the descriptions, functions, procedures, proposals, methods and / or flowcharts disclosed herein from one or more other devices. For example, one or more transceivers 106, 206 are connected to one or more processors 102, 202 and can transmit and receive radio signals. For example, one or more processors 102, 202 can control one or more transceivers 106, 206 to transmit user data, control information or radio signals to one or more other devices. Also, one or more processors 102, 202 can control one or more transceivers 106, 206 to receive user data, control information or radio signals from one or more other devices. Also, one or more transceivers 106, 206 are connected to one or more antennas 108, 208, and one or more transceivers 106, 206 are configured to transmit and receive user data, control information, radio signals / channels, etc. mentioned in the descriptions, functions, procedures, proposals, methods and / or flowcharts disclosed herein by one or more antennas 108, 208. In this specification, one or more antennas are multiple physical antennas or multiple logical antennas (e.g., antenna ports). One or more transceivers 106, 206 convert (Convert) the received radio signals / channels, etc. from RF band signals to baseband signals in order to process the received user data, control information, radio signals / channels, etc. using one or more processors 102, 202. One or more transceivers 106, 206 convert the user data, control information, radio signals / channels, etc. processed using one or more processors 102, 202 from baseband signals to RF band signals. For this purpose, one or more transceivers 106, 206 include (analog) oscillators and / or filters.

[0196] Utilization Example of Wireless Device to which the Present Invention is Applied

[0197] Figure 10 shows another example of a wireless device to which the present invention is applied. The wireless device is embodied in various forms depending on the usage example / service (see FIG. 8).

[0198] Referring to FIG. 10, the wireless devices 100 and 200 correspond to the wireless devices 100 and 200 of FIG. 9 and are composed of various elements, components, units / parts, and / or modules. For example, the wireless devices 100 and 200 include a communication unit 110, a control unit 120, a memory unit 130, and additional elements 140. The communication unit includes a communication circuit 112 and a transceiver 114. For example, the communication circuit 112 includes one or more processors 102 and 202 and / or one or more memories 104 and 204 in FIG. 9. For example, the transceiver 114 includes one or more transceivers 106 and 206 and / or one or more antennas 108 and 208 of FIG. 9. The control unit 120 is electrically connected to the communication unit 110, the memory unit 130, and the additional elements 140 and controls various operations of the wireless device. For example, the control unit 120 controls the electrical / mechanical operations of the wireless device based on programs / codes / instructions / information stored in the memory unit 130. The control unit 120 also transmits the information stored in the memory unit 130 to the outside (e.g., other communication devices) through a wireless / wired interface by the communication unit 110, or stores the information received from the outside (e.g., other communication devices) through a wireless / wired interface by the communication unit 110 in the memory unit 130.

[0199] The additional element 140 is configured variously depending on the type of wireless device. For example, the additional element 140 includes any one of a power unit / battery, an input / output unit (I / O unit), a drive unit, and a computer unit. Without being limited thereto, the wireless device is embodied in the form of a robot (Figs. 8, 100a), a vehicle (Figs. 8, 100b-1, 100b-2), an XR device (Figs. 8, 100c), a portable device (Figs. 8, 100d), a home appliance (Figs. 8, 100e), an IoT device (Figs. 8, 100f), a digital broadcast terminal, a hologram device, a public safety device, an MTC device, a medical device, a fintech device (or financial device), a security device, a climate / environment device, an AI server / device (Figs. 8, 400), a base station (Figs. 8, 200), and a network node, etc. The wireless device is movable depending on the usage example / service or is used at a fixed location.

[0200] In Fig. 10, various elements, components, units / parts, and / or modules within the wireless devices 100 and 200 are all connected to each other by a wired interface or at least a part thereof is wirelessly connected by the communication unit 110. For example, within the wireless devices 100 and 200, the control unit 120 and the communication unit 110 are wired-connected, and the control unit 120 and the first unit (e.g., 130, 140) are wirelessly connected by the communication unit 110. Also, each element, component, unit / part, and / or module within the wireless devices 100 and 200 further includes one or more elements. For example, the control unit 120 is composed of a set of one or more processors. For example, the control unit 120 is composed of a set including a communication control processor, an application processor, an ECU (Electronic control Unit), a graphics processing processor, a memory control processor, etc. As another example, the memory unit 130 is composed of a RAM (Random Access Memory), a DRAM (Dynamic RAM), a ROM (Read Only Memory), a flash memory, a volatile memory, a non-volatile memory, and / or a combination thereof.

[0201] Example of Vehicle or Autonomous Driving Vehicle to which the Present Invention is Applied

[0202] FIG. 11 is a diagram illustrating a vehicle or an autonomous vehicle to which the present invention is applied. The vehicle or the autonomous vehicle is embodied as a mobile robot, a vehicle, a train, an aerial vehicle (AV) with / without a pilot, a ship, or the like.

[0203] Referring to FIG. 11, the vehicle or the autonomous vehicle 100 includes an antenna unit 108, a communication unit 110, a control unit 120, a driving unit 140a, a power supply unit 140b, a sensor unit 140c, and an autonomous driving unit 140d. The antenna unit 108 is constituted by a part of the communication unit 110. Blocks 110 / 130 / 140a to 140d respectively correspond to blocks 110 / 130 / 140 in FIG. 10.

[0204] The communication unit 110 transmits and receives signals (such as data, control signals, etc.) with external devices such as other vehicles, base stations (e.g., base stations, roadside units, etc.), and servers. The control unit 120 controls the elements of the vehicle or the autonomous driving vehicle 100 to perform various operations. The control unit 120 includes an ECU (Electronic Control Unit). The driving unit 140a enables the vehicle or the autonomous driving vehicle 100 to travel on the ground. The driving unit 140a includes an engine, a motor, a power train, wheels, brakes, a steering device, etc. The power supply unit 140b supplies power to the vehicle or the autonomous driving vehicle 100 and includes a wired / wireless charging circuit, a battery, etc. The sensor unit 140c can obtain vehicle state, surrounding environment information, user information, etc. The sensor unit 140c includes an IMU (inertial measurement unit) sensor, a collision sensor, a wheel sensor, a speed sensor, an inclination sensor, a weight sensing sensor, a heading sensor, a position module, a vehicle forward / backward sensor, a battery sensor, a fuel sensor, a tire sensor, a steering sensor, a temperature sensor, a humidity sensor, an ultrasonic sensor, an illuminance sensor, a pedal position sensor, etc. The autonomous driving unit 140d implements technologies such as maintaining the lane during driving, automatically adjusting the speed like an adaptive cruise control, automatically driving along a predetermined route, and automatically setting and driving along a route when a destination is set.

[0205] As an example, the communication unit 110 receives map data, traffic information data, etc. from an external server. The autonomous driving unit 140d generates an autonomous driving route and a drive plan based on the obtained data. The control unit 120 controls the driving unit 140a so that the vehicle or the autonomous driving vehicle 100 moves along the autonomous driving route according to the drive plan (for example, speed / direction adjustment). The communication unit 110 periodically obtains the latest traffic information data from the external server during autonomous driving, and also obtains the surrounding traffic information data from the surrounding vehicles. In addition, the sensor unit 140c obtains the vehicle state and the surrounding environment information during autonomous driving. The autonomous driving unit 140d updates the autonomous driving route and the drive plan based on the newly obtained data / information. The communication unit 110 transmits information regarding the vehicle position, the autonomous driving route, the drive plan, etc. to the external server. The external server can predict traffic information data in advance using AI technology or the like based on the information collected from the vehicle or the autonomous driving vehicle, and provide the predicted traffic information data to the vehicle or the autonomous driving vehicle.

[0206] It is obvious to those skilled in the art that the present invention can be embodied in other specific forms without departing from the features of the present invention. Therefore, the above detailed description should not be construed restrictively in all aspects, but should be considered as exemplary. The scope of the present invention should be determined by a reasonable interpretation of the appended claims, and all changes within the equivalent scope of the present invention are included in the scope of the present invention.

[0207] As described above, the present invention can be applied to various wireless communication systems.

Claims

1. A method for a UE (user equipment) to monitor a control channel in a wireless communication system, comprising: receiving configuration information for at least one serving cell included in a serving cell set, the configuration information including at least configuration related to a first SSSG (search space set group) having a first group index and configuration related to a second SSSG having a second group index; performing PDCH (physical downlink control channel) monitoring according to a search space set of the first SSSG based on the configuration information; performing the SSSG switching based on detection of a DCI (downlink control information) format used to notify the SSSG switching, including: Based on the serving cell set including a serving cell having a 960 kHz subcarrier spacing, the SSSG switching is at the start of the first slot of the slot-group of the Xs slot after at least a predetermined number P switch of symbols of the last symbol of the PDCCH having the DCI format. i) starting the PDCH monitoring according to a search space set of the second SSSG; ii) stopping the PDCH monitoring according to the search space set of the first SSSG; wherein slot-groups of Xs slots are consecutive; based on the serving cell set including a serving cell having a subcarrier spacing of 960 kHz, the UE determines a slot and a symbol within the slot for starting or stopping the PDCH monitoring for the SSSG switching based on a maximum Xs value for the serving cell set.

2. The method according to claim 1, further comprising receiving a cell group configuration for switching related to the serving cell set, wherein based on the cell group configuration for switching, the SSSG switching is performed for all serving cells within the serving cell set.

3. The method according to claim 2, wherein the cell group configuration for switching is an RRC (radio resource control) parameter cellGroupForSwitch.

4. the previously determined number P switch The method according to claim 1, further comprising receiving information regarding switch .

5. the predetermined number P switch is the method according to claim 1, which is predefined for the sub-carrier interval of 960 kHz and the processing capability of the UE.

6. The method according to claim 1, wherein each search space set within the first SSSG and the second SSSG is configured based on one of the Xs values of the Xs values for the serving cell set.

7. The method according to claim 1, wherein each Xs value for the serving cell set is related to a set of search spaces configured for the serving cell set. **Claim 8** Further comprising receiving information regarding the position of the SSSG flag field within the DCI format for the serving cell set, The method according to claim 1, wherein the DCI format is DCI format 2_0. **Claim 9** A UE (user equipment) for monitoring a control channel in a wireless communication system, At least one transceiver, At least one processor, At least one computer memory operably connected to the at least one processor and configured to store instructions, The instructions, when executed, cause the at least one processor to Receive configuration information for at least one serving cell included in a serving cell set, the configuration information including at least a configuration related to a first SSSG (search space set group) having a first group index and a configuration related to a second SSSG having a second group index, Perform PDCCH (physical downlink control channel) monitoring according to a search space set of the first SSSG based on the configuration information, Perform the SSSG switching based on detection of a DCI (downlink control information) format used to notify the SSSG switching, Cause to perform operations including Based on the serving cell set including a serving cell having a 960 kHz subcarrier spacing, the SSSG switching is at the start of the first slot of the slot-group of the Xs slot after at least a predetermined number P switch of symbols of the last symbol of the PDCCH having the DCI format. i) Start the PDCCH monitoring according to a search space set of the second SSSG, ii) Stop the PDCCH monitoring according to the search space set of the first SSSG, Including, the slot-group of the Xs slot is continuous, Based on the serving cell set including the serving cell having a subcarrier spacing of 960 kHz, the UE determines a slot and a symbol within the slot for starting or stopping the PDCCH monitoring for the SSSG switching based on a maximum Xs value for the serving cell set. **Claim 10** A method for a BS (base station) to transmit a control channel in a wireless communication system, comprising: transmitting configuration information for at least one serving cell included in a serving cell set, the configuration information including at least configuration related to a first SSSG (search space set group) having a first group index and configuration related to a second SSSG having a second group index; transmitting at least one PDCCH (physical downlink control channel) according to a search space set of the first SSSG based on the configuration information; performing the SSSG switching based on transmission of a DCI (downlink control information) format used to notify the SSSG switching, including: Based on the serving cell set including a serving cell having a 960 kHz subcarrier spacing, the SSSG switching is at the start of the first slot of the slot-group of the Xs slot after at least a predetermined number P switch of symbols of the last symbol of the PDCCH having the DCI format. i) starting to transmit at least one PDCCH according to the search space set of the second SSSG; ii) stopping transmitting at least one PDCCH according to the search space set of the first SSSG; wherein the slot-groups of the Xs slots are consecutive; based on the serving cell set including a serving cell having a subcarrier spacing of 960 kHz, the BS determines a slot and a symbol within the slot for performing the SSSG switching based on the maximum Xs value among the Xs values for the serving cell set. **Claim 11** A BS (base station) for transmitting a control channel in a wireless communication system, comprising: at least one transceiver; at least one processor; at least one computer memory operably connected to the at least one processor and configured to store instructions, wherein the instructions, when executed, cause the at least one processor to: transmit configuration information for at least one serving cell included in a serving cell set, the configuration information including at least configuration related to a first SSSG (search space set group) having a first group index and configuration related to a second SSSG having a second group index; Transmitting at least one physical downlink control channel (PDCCH) according to the search space set of the first SSSG based on the setting information; Performing the SSSG switching based on transmission of a downlink control information (DCI) format used to notify SSSG switching; Causing an operation including: Based on the serving cell set including a serving cell having a subcarrier spacing of 960 kHz, the SSSG switching is at the start of the first slot of a slot-group of an Xs slot after at least a predetermined number P switch symbols of the last symbol of the PDCCH having the DCI format. i) Starting to transmit at least one PDCCH according to the search space set of the second SSSG; ii) Stopping transmitting at least one PDCCH according to the search space set of the first SSSG; wherein the slot-groups of the Xs slots are consecutive; Based on the serving cell set including the serving cell having a subcarrier spacing of 960 kHz, the BS determines a slot and symbols within the slot for the SSSG switching based on the maximum Xs value among the Xs values for the serving cell set.

12. Further including transmitting a cell group setting for switching related to the serving cell set, wherein the SSSG switching is performed for all serving cells within the serving cell set based on the cell group setting for switching. The BS according to claim 11.

13. The cell group setting for switching is the radio resource control (RRC) parameter cellGroupForSwitch. The BS according to claim 12.

14. transmitting information regarding the predetermined number P switch The BS according to claim 11, further comprising

15. the predetermined number P switch is the BS according to claim 11, which is predefined for the subcarrier spacing of 960 kHz and the processing capabilities of the UE (user equipment).

16. Each search space set within the first SSSG and the second SSSG is set based on one Xs value among the Xs values for the serving cell set. The BS according to claim 11.

17. Each of the Xs values for the serving cell set is related to the search space set set for the serving cell set. The BS according to claim 11.

18. Further including transmitting information regarding the position of the SSSG flag field in the DCI format for the serving cell set, wherein the DCI format is DCI format 2_0. The BS according to claim 11.

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