Method and apparatus for transmitting and receiving signals in a wireless communication system

Abstract

According to at least one of various embodiments of the present invention, a terminal monitors physical downlink control channel (PDCCH) candidates and detects downlink control information (DCI) by monitoring the PDCCH candidates, and the DCI supports multi-cell scheduling based on a cell combination for a plurality of cells configured in the terminal, and a payload size of the DCI is determined based on a first cell combination among the cell combinations in which a total number of DCI bits required for co-scheduled cells is maximum.

Description

[Technical field]

[0001] The present invention relates to wireless communication systems, and more particularly to a method and apparatus for transmitting or receiving uplink / downlink radio signals in a wireless communication system. [Background technology]

[0002] Wireless communication systems have been widely deployed to provide various communication services such as voice and data. In general, wireless communication systems are multiple access systems that can support communication with multiple users by sharing available system resources (bandwidth, transmission power, etc.). Examples of multiple access systems include code division multiple access (CDMA) systems, frequency division multiple access (FDMA) systems, time division multiple access (TDMA) systems, orthogonal frequency division multiple access (OFDMA) systems, and single carrier frequency division multiple access (SC-FDMA) systems. Summary of the Invention [Problem to be solved by the invention]

[0003] The technical problem to be solved is to provide a method and an apparatus for efficiently performing a process of transmitting and receiving a radio signal.

[0004] The technical problem to be achieved is not limited thereto, and other technical problems not mentioned will be clearly understood by those having ordinary skill in the art to which the present invention pertains from the following description. [Means for solving the problem]

[0005] According to an aspect of the present invention, there is provided a method for a terminal receiving a signal in a wireless communication system, the method including: monitoring physical downlink control channel (PDCCH) candidates; and detecting downlink control information (DCI) through monitoring of the PDCCH candidates. The DCI may support multi-cell scheduling based on cell combinations regarding a plurality of cells configured in the UE. A payload size of the DCI may be determined based on a first cell combination in which a total number of bits required for co-scheduled cells from among the cell combinations.

[0006] The payload of the DCI is determined based on the combined size of all DCI fields for the first cell combination.

[0007] Cells co-scheduled by the DCI are indicated to be in one of the cell combinations.

[0008] The DCI includes information on a first DCI field for each of a first cell and a second cell that are scheduled together. Based on the first cell having a lower serving cell index than the second cell, the information on the first DCI field for the first cell is arranged in the DCI before the information on the first DCI field for the second cell. The first DCI field includes at least one of a modulation and coding scheme (MCS) field, a new data indicator (NDI) field, a redundancy version (RV) field, a hybrid automatic repeat request (HARQ) process ID field, a frequency domain resource allocation (FDRA) field, a time domain resource allocation (TDRA) field, and a transmission power command (TPC) field for a physical uplink shared channel (PUSCH).

[0009] Among the cells scheduled together by the DCI, a scheduled signal is transmitted or received only to the other cells except at least one inactive cell. The at least one inactive cell includes at least one of a deactivated SCell (secondary cell), a cell operating as a Dormant BWP (bandwidth part), a cell whose resource allocated by the DCI overlaps with a semi-static resource whose UL (uplink) / DL (downlink) directions are set differently, and a cell whose frequency resource information indicated by the DCI is not valid. Hybrid automatic repeat request-acknowledgement (HARQ-ACK) information is configured for the other cells except the at least one inactive cell, or is configured to include negative acknowledgement (NACK) information for the at least one inactive cell. A DCI field value for the at least one inactive cell in the DCI is set based on information about a specific BWP (bandwidth part).

[0010] According to another aspect of the present invention, there is provided a processor-readable recording medium having a program recorded thereon for carrying out the above-described method.

[0011] According to another aspect, there is provided a terminal for performing the above-mentioned method.

[0012] According to yet another aspect, there is provided an apparatus for controlling a terminal to perform the method described above.

[0013] According to one aspect, a method for transmitting a signal by a base station in a wireless communication system includes generating downlink control information (DCI) and transmitting the DCI to a terminal based on at least one of physical downlink control channel (PDCCH) candidates of the terminal. The DCI supports multi-cell scheduling based on a cell combination for a plurality of cells configured in the terminal. A payload size of the DCI is determined based on a first cell combination among the cell combinations, which has a maximum total number of DCI bits required for co-scheduled cells.

[0014] According to yet another aspect, there is provided a base station for performing the above-described method. Effect of the Invention

[0015] According to at least one of various embodiments, it is possible to efficiently transmit and receive radio signals in a wireless communication system.

[0016] The effects obtained by the present invention are not limited to those mentioned above, and other effects not mentioned will be clearly understood by those having ordinary skill in the art to which the present invention pertains from the following description. [Brief description of the drawings]

[0017] [Figure 1] 1 is a diagram illustrating physical channels used in a 3GPP (registered trademark) system, which is an example of a wireless communication system, and a general signal transmission method using these channels.

[0018] [Diagram 2] FIG. 1 illustrates a structure of a radio frame.

[0019] [Diagram 3] FIG. 2 illustrates a resource grid of slots.

[0020] [Figure 4] A diagram showing an example of mapping physical channels within a slot.

[0021] [Diagram 5] A diagram illustrating a PDCCH / PDSCH reception and ACK / NACK transmission process.

[0022] [Figure 6] FIG. 1 illustrates a PUSCH (Physical Uplink Shared Channel) transmission process.

[0023] [Figure 7] FIG. 2 illustrates an example of carrier merging.

[0024] [Figure 8] FIG. 1 illustrates a wireless communication system that supports unlicensed bands.

[0025] [Figure 9] FIG. 1 illustrates a method for occupying resources in an unlicensed spectrum.

[0026] [Figure 10] A diagram to explain a bit arrangement for specific fields in a multi-cell scheduling DCI according to one embodiment.

[0027] [Figure 11] A diagram to explain the payload size in a multiple-cell scheduling DCI according to one embodiment.

[0028] [Figure 12] 1 is a diagram illustrating a method for a terminal to receive a signal according to one embodiment.

[0029] [Figure 13] 1 is a diagram illustrating a method in which a base station transmits a signal according to one embodiment.

[0030] [Figure 14-17] 1 is a diagram illustrating a communication system 1 and wireless devices applicable to the present invention.

[0031] [Figure 18] FIG. 2 is a diagram illustrating a DRX (Discontinuous Reception) operation applicable to the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0032] The following technologies can be used for various wireless access systems such as code division multiple access (CDMA), frequency division multiple access (FDMA), time division multiple access (TDMA), orthogonal frequency division multiple access (OFDMA), single carrier frequency division multiple access (SC-FDMA), etc. CDMA can be implemented by radio technologies such as Universal Terrestrial Radio Access (UTRA) and CDMA2000. TDMA can be implemented by radio technologies such as Global System for Mobile communications (GSM) / General Packet Radio Service (GPRS) / Enhanced Data Rates for GSM Evolution (EDGE). OFDMA can be implemented by radio technologies such as IEEE 802.11 (Wi-Fi), IEEE 802.16 (WiMAX), IEEE 802-20, Evolved UTRA (E-UTRA), etc. UTRA is part of the Universal Mobile Telecommunications System (UMTS). 3GPP (3rd Generation Partnership Project) LTE (long term evolution) is part of E-UMTS (Evolved UMTS) that uses E-UTRA, and LTE-A is an evolution of 3GPP LTE. 3GPP NR (New Radio or New Radio Access Technology) is an evolution of 3GPP LTE / LTE-A.

[0033] As more communication devices require larger communication capacity, the need for improved mobile broadband (eMBB) communication compared to existing radio access technology (RAT) is emerging. In addition, large-scale MTC (massive machine type communications), which connects multiple devices and objects to provide various services anytime and anywhere, is one of the important issues to be considered in next-generation communications. In addition, URLLC (Ultra-Reliable and Low Latency Communication) considering reliability and latency-sensitive services / UEs is being discussed. Thus, the introduction of next-generation RATs considering eMBB (enhanced mobile broadband communication), large-scale MTC, URLLC (Ultra-Reliable and Low Latency Communication), etc. is being discussed, and in the present invention, the corresponding technology is referred to as NR (New radio or New RAT) for convenience.

[0034] For clarity of explanation, 3GPP NR will be mainly described, but the technical idea of ​​the present invention is not limited thereto.

[0035] In this specification, the term "setting" may be replaced with the term "configure / configuration", and the two terms may be used interchangeably. Conditional expressions (e.g., "if", "in a case", or "when") may be replaced with expressions such as "based on that" or "in a state / status". The operation or SW / HW configuration of a terminal / base station due to the satisfaction of the relevant condition may be inferred / understood. In addition, in signal transmission / reception between wireless communication devices (e.g., base station, terminal), if the process of the receiving (or transmitting) side can be inferred / understood from the process of the transmitting (or receiving) side, the explanation may be omitted. For example, the signal determination / generation / encoding / transmission of the transmitting side can be understood as the signal monitoring reception / decoding / determination of the receiving side. In addition, an expression that a terminal performs (or does not perform) a specific operation may also be interpreted as the base station operating while expecting / assuming (or expecting / assuming not to perform) the specific operation of the terminal. The expression that the base station performs (or does not perform) a specific operation can also be interpreted as the terminal expecting / assuming (or expecting / assuming not to perform) the execution of a specific operation of the base station. In addition, in the following description, the divisions and indexes of each section, embodiment, example, option, method, solution, etc. are for convenience of explanation and should not be interpreted as meaning that each necessarily constitutes an independent invention or that each necessarily must be implemented individually. In addition, in describing each section, embodiment, example, option, method, solution, etc., unless there is an explicitly conflicting / opposing technology, it is inferred / interpreted that at least some of them may be combined and implemented together, or at least some may be omitted and implemented.

[0036] In a wireless communication system, a terminal receives information from a base station through a downlink (DL), and transmits information from the base station through an uplink (UL). Information transmitted and received between the base station and the terminal includes data and various control information, and various physical channels exist depending on the type / purpose of the information transmitted and received.

[0037] FIG. 1 is a diagram illustrating physical channels used in a 3GPP NR system and a typical signal transmission method using these channels.

[0038] A terminal that has been turned on in a power-off state or that has newly entered a cell performs an initial cell search operation such as establishing synchronization with a base station in step S101. To this end, the terminal receives a synchronization signal block (SSB) from the base station. The SSB includes a primary synchronization signal (PSS), a secondary synchronization signal (SSS) and a physical broadcast channel (PBCH). The terminal establishes synchronization with the base station based on the PSS / SSS and obtains information such as a cell identity (cell ID). The terminal also obtains broadcast information within the cell based on the PBCH. In addition, the terminal can receive a downlink reference signal (DL RS) during the initial cell search stage to check the state of the downlink channel.

[0039] After completing the initial cell search, in step S102, the terminal receives a physical downlink control channel (PDCCH) and a physical downlink shared channel (PDSCH) based on information of the physical downlink control channel to obtain more specific system information.

[0040] Thereafter, the terminal performs a random access procedure such as steps S103 to S106 to complete connection to the base station. To this end, the terminal transmits a preamble through a physical random access channel (PRACH) (S103) and receives a response message to the preamble through a physical downlink control channel and a corresponding physical downlink shared channel (S104). In the case of contention based random access, the terminal performs a contention resolution procedure such as transmitting a further physical random access channel (S105) and receiving a physical downlink control channel and a corresponding physical downlink shared channel (S106).

[0041] After performing this procedure, the terminal then receives a physical downlink control channel / physical downlink shared channel (S107) and transmits a physical uplink shared channel (Physical Uplink Shared Channel, PUSCH) / physical uplink control channel (Physical Uplink Control Channel, PUCCH) as a general uplink / downlink signal transmission procedure (S108). The control information transmitted by the terminal to the base station is collectively referred to as uplink control information (UCI). UCI includes HARQ ACK / NACK (Hybrid Automatic Repeat and reQuest Acknowledgement / Negative-ACK), SR (Scheduling Request), CSI (Channel State Information), etc. CSI includes CQI (Channel Quality Indicator), PMI (Precoding Matrix Indicator), RI (Rank Indication), etc. UCI is generally transmitted via PUCCH, but when control information and traffic data need to be transmitted simultaneously, it is transmitted via PUSCH. In addition, UCI can be transmitted aperiodically via PUSCH upon request / instruction from the network.

[0042] Meanwhile, the voluntary access procedure (RACH procedure) is not limited to the one for initial network access (e.g., S103 to S106) and can be used for various purposes. For example, the voluntary access procedure can be used for any of the RRC connection re-establishment procedure, handover, UE-triggered UL data transmission, transition from RRC_INACTIVE, SCell time alignment, system information request and beam failure recovery, and UL resource request, but is not limited thereto. The UE can obtain UL synchronization and / or UL transmission resources through the voluntary access procedure.

[0043] FIG. 2 illustrates the structure of a radio frame. In NR, uplink and downlink transmissions 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 depending on the cyclic prefix (CP). If a general CP is used, each slot contains 14 symbols. If an extended CP is used, each slot contains 12 symbols.

[0044] Table 1 illustrates that the number of symbols per slot, the number of slots per frame, and the number of slots per subframe change depending on the SCS when a general CP is used.

[0045] [Table 1]

[0046] *N slot symb :Number of symbols in the slot

[0047] *N frame,u slot : Number of slots in the frame

[0048] *N subframe,u slot : Number of slots in a subframe

[0049] Table 2 illustrates that the number of symbols per slot, the number of slots per frame, and the number of slots per subframe vary with the SCS when an extended CP is used.

[0050] [Table 2]

[0051] The frame structure is exemplary only, and the number of subframes, slots, and symbols within a frame can vary.

[0052] In the NR system, OFDM numerology (e.g., SCS) can be set to be different between multiple cells merged into one terminal. Accordingly, the (absolute time) duration of time resources (e.g., SF, slot, or TTI) (for convenience, commonly referred to as TU (Time Unit)) consisting of the same number of symbols can be set to be different between the merged cells. Here, the symbols include OFDM symbols (or CP-OFDM symbols) and SC-FDMA symbols (or Discrete Fourier Transform-spread-OFDM, DFT-s-OFDM symbols).

[0053] FIG. 3 is a diagram illustrating a resource grid of a slot. A slot includes a number of symbols in the time domain. For example, in the case of a general CP, one slot includes 14 symbols, while in the case of an extended CP, one slot includes 12 symbols. A carrier includes a number of subcarriers in the frequency domain. A resource block (RB) is defined as a number of (e.g., 12) consecutive subcarriers in the frequency domain. A BWP is defined as a number of consecutive physical RBs (PRBs) in the frequency domain and can correspond to one numerology (e.g., SCS, CP length, etc.). A carrier includes up to N (e.g., 5) BWPs. Data communication is performed in an activated BWP, and only one BWP is activated for one terminal. In the resource grid, each element is called a resource element (RE), and one complex symbol can be mapped to it.

[0054] Figure 4 is a diagram showing an example of mapping physical channels within a slot. PDCCH is transmitted in the DL control region, and PDSCH is transmitted in the DL data region. PUCCH is transmitted in the UL control region, and PUSCH is transmitted in the UL data region. GP provides a time gap when the base station and the terminal switch from a transmission mode to a reception mode or from a reception mode to a transmission mode. Some symbols at the time of switching from DL to UL within a subframe can be set as GP.

[0055] Each physical channel is described in more detail below.

[0056] The PDCCH carries Downlink Control Information (DCI). For example, the PCCCH (i.e., DCI) carries the transmission format and resource allocation of the DL-SCH (downlink shared channel), resource allocation information for the UL-SCH (uplink shared channel), paging information for the PCH (paging channel), system information on the DL-SCH, resource allocation information for higher layer control messages such as voluntary access responses transmitted on the PDSCH, transmission power control commands, activation / deactivation of configured scheduling (CS), etc. The DCI includes a cyclic redundancy check (CRC), and the CRC is masked / scrambled to various identifiers (e.g., Radio Network Temporary Identifier, RNTI) depending on the owner or use of the PDCCH. For example, if the PDCCH is for a specific terminal, the CRC is masked to a terminal identifier (e.g., cell-RNTI, C-RNTI). If the PDCCH is for paging, the CRC is masked to a P-RNTI (Paging-RNTI). If the PDCCH is for system information (e.g., System Information Block, SIB), the CRC is masked with a System Information RNTI (SI-RNTI). If the PDCCH is for an unsolicited access response, the CRC is masked with a Random Access-RNTI (RA-RNTI).

[0057] The PDCCH is composed of 1, 2, 4, 8, or 16 CCEs (Control Channel Elements) depending on the AL (Aggregation Level). A CCE is a logical allocation unit used to provide a PDCCH with a predetermined code rate according to the radio channel condition. A CCE is composed of 6 REGs (Resource Element Groups). A REG is defined by one OFDM symbol and one (P)RB. The PDCCH is transmitted by a CORESET (Control Resource Set). A CORESET is defined by a set of REGs having a given neurology (e.g., SCS, CP length, etc.). Multiple CORESETs for one UE can be overlapped in the time / frequency domain. A CORESET is set by system information (e.g., Master Information Block, MIB) or UE-specific higher layer (e.g., Radio Resource Control, RRC, layer) signaling. Specifically, the number of RBs and the number of OFDM symbols (maximum 3) constituting a CORESET are set by higher layer signaling.

[0058] For PDCCH reception / detection, the terminal monitors PDCCH candidates. PDCCH candidates indicate the CCEs that the terminal monitors for PDCCH detection. Each PDCCH candidate is defined by 1, 2, 4, 8, or 16 CCEs depending on the AL. Monitoring includes (blind) decoding the PDCCH candidates. The set of PDCCH candidates that the terminal monitors is defined as a PDCCH search space (SS). The search space includes a common search space (CSS) or a UE-specific search space (USS). The terminal can obtain DCI by monitoring PDCCH candidates in one or more search spaces configured by MIB or higher layer signaling. Each CORESET is associated with one or more search spaces, and each search space is associated with one COREST. The search space is defined based on the following parameters:

[0059] - controlResourceSetId: Indicates the CORESET associated with the search space.

[0060] - monitoringSlotPeriodicityAndOffset: indicates the PDCCH monitoring period (in slots) and the PDCCH monitoring period offset (in slots).

[0061] - monitoringSymbolsWithinSlot: indicates the PDCCH monitoring symbols within the slot (e.g. indicates the first symbol of the SORESET).

[0062] - nrofCandidates: indicates the number of PDCCH candidates (one of 0, 1, 2, 3, 4, 5, 6, 8) for AL={1, 2, 4, 8, 16}.

[0063] *An opportunity (e.g., time / frequency resource) for monitoring a PDCCH candidate is defined as a PDCCH (monitoring) opportunity. One or more PDCCH (monitoring) opportunities are configured within a slot.

[0064] Table 3 illustrates the characteristics of each search space type.

[0065] [Table 3]

[0066] Table 4 illustrates an example of a DCI format transmitted via the PDCCH.

[0067] [Table 4]

[0068] DCI format 0_0 is used to schedule a TB-based (or TB-level) PUSCH, and DCI format 0_1 ​​is used to schedule a TB-based (or TB-level) PUSCH or a Code Block Group (CBG)-based (or CBG-level) PUSCH. DCI format 1_0 is used to schedule a TB-based (or TB-level) PDSCH, and DCI format 1_1 is used to schedule a TB-based (or TB-level) PDSCH or a CBG-based (or CBG-level) PDSCH. DCI format 0_0 / 0_1 is called UL grant DCI or UL scheduling information, and DCI format 1_0 / 1_1 is called DL grant DCI or DL ​​scheduling information. DCI format 2_0 is used to deliver dynamic slot format information (e.g., dynamic SFI) to a terminal, and DCI format 2_1 is used to deliver downlink pre-Emption information to a terminal. DCI format 2_0 and / or DCI format 2_1 are transmitted to terminals in a corresponding group via a group common PDCCH, which is a PDCCH transmitted to terminals defined in one group.

[0069] DCI format 0_0 and DCI format 1_0 are called fallback DCI formats, and DCI format 0_1 ​​and DCI format 1_1 are called non-fallback DCI formats. The fallback DCI format maintains the same DCI size / field configuration regardless of the terminal settings. On the other hand, the non-fallback DCI format has a different DCI size / field configuration depending on the terminal settings.

[0070] PDSCH carries downlink data (e.g. DL-SCH transport block, DL-SCH TB) and uses modulation methods such as QPSK (Quadrature Phase Shift Keying), 16QAM (Quadrature Amplitude Modulation), 64QAM, and 256QAM. The TB is encoded to generate a codeword. PDSCH carries up to two codewords. Scrambling and modulation mapping are performed for each codeword, and the modulation symbols generated from each codeword are mapped to one or more layers. Each layer is mapped to resources together with DMRS (Demodulation Reference Signal) to generate an OFDM symbol signal, which is then transmitted by the corresponding antenna port.

[0071] The PUCCH carries Uplink Control Information (UCI), which includes:

[0072] - SR (Scheduling Request): Information used to request UL-SCH resources.

[0073] - HARQ-ACK: A response to a downlink data packet (e.g., a codeword) on a PDSCH. It indicates whether the downlink data packet is successfully received. One bit of HARQ-ACK is transmitted as a response to a single codeword, and two bits of HARQ-ACK are transmitted as a response to two codewords. HARQ-ACK responses include positive ACK (simply, ACK), negative ACK (hereinafter, NACK), DTX (Discontinuous Transmission), or NACK / DTX. Here, the term HARQ-ACK is used interchangeably with HARQ ACK / NACK and ACK / NACK.

[0074] CSI (Channel State Information): Feedback information for a downlink channel. Multiple Input Multiple Output (MIMO)-related feedback information includes a Rank Indicator (RI) and a Precoding Matrix Indicator (PMI).

[0075] Table 5 shows an example of a PUCCH format. According to the PUCCH transmission length, it can be divided into Short PUCCH (formats 0 and 2) and Long PUCCH (formats 1, 3 and 4).

[0076] [Table 5]

[0077] PUCCH format 0 carries UCI with a maximum size of 2 bits and is mapped and transmitted based on a sequence. Specifically, the terminal transmits one of a plurality of sequences via a PUCCH with PUCCH format 0 to transmit a specific UCI to the base station. The terminal transmits a PUCCH with PUCCH format 0 within a PUCCH resource for a corresponding SR setting only when transmitting a positive SR.

[0078] PUCCH format 1 carries UCI with a maximum size of 2 bits, and the modulation symbols are spread by an orthogonal cover code (OCC) in the time domain (set differently depending on whether frequency hopping is used or not). DMRS is transmitted in symbols where no modulation symbols are transmitted (i.e., transmitted using TDM (Time Division Multiplexing)).

[0079] PUCCH format 2 carries UCI with a bit size larger than 2 bits, and modulation symbols are transmitted after frequency division multiplexing (FDM) with DMRS. DM-RS is located at symbol indexes #1, #4, #7, and #10 in a 1 / 3 density resource block. A Pseudo Noise (PN) sequence is used for the DM_RS sequence. Frequency hopping can be activated for the 2-symbol PUCCH format 2.

[0080] In PUCCH format 3, terminal multiplexing is not performed within the same physical resource block, and UCI with a bit size larger than 2 bits is carried. That is, the PUCCH resource of PUCCH format 3 does not include an orthogonal cover code. The modulation symbol is transmitted after being subjected to TDM (Time Division Multiplexing) with DMRS.

[0081] PUCCH format 4 supports multiplexing of up to four terminals in the same physical resource block and carries UCI with a bit size larger than 2 bits. That is, the PUCCH resource of PUCCH format 3 includes an orthogonal cover code. Modulation symbols are transmitted after being time division multiplexed (TDM) with DMRS.

[0082] The PUSCH carries uplink data (e.g., UL-SCH transport block, UL-SCH TB) and / or uplink control information (UCI) and is transmitted based on a cyclic prefix-orthogonal frequency division multiplexing (CP-OFDM) waveform or a discrete Fourier transform-spread-orthogonal frequency division multiplexing (DFT-s-OFDM) waveform. When the PUSCH is transmitted based on the DFT-s-OFDM waveform, the terminal applies transform precoding to transmit the PUSCH. As an example, when transform precoding is not possible (e.g., transform precoding is disabled), the terminal transmits the PUSCH based on the CP-OFDM waveform, and when transform precoding is possible (e.g., transform precoding is enabled), the terminal transmits the PUSCH based on the CP-OFDM waveform or the DFT-s-OFDM waveform. PUSCH transmissions may be dynamically scheduled by UL grants in the DCI or semi-statically scheduled (configured grant) based on higher layer (e.g., RRC) signaling (and / or Layer 1 (L1) signaling (e.g., PDCCH)). PUSCH transmissions may be codebook-based or non-codebook-based.

[0083] Figure 5 illustrates a process of receiving PDCCH / PDSCH and transmitting ACK / NACK. Referring to Figure 5, a terminal detects a PDCCH in slot #n. Here, the PDCCH includes downlink scheduling information (e.g., DCI format 1_0, 1_1), and the PDCCH indicates DL allocation-to-PDSCH offset (K0) and PDSCH-HARQ-ACK report offset (K1). For example, DCI formats 1_0, 1_1 include the following information:

[0084] - Frequency domain resource assignment: Indicates the RB set assigned to the PDSCH.

[0085] - Time domain resource assignment: Indicates K0 (e.g. slot offset), the starting position of the PDSCH within slot #n+K0 (e.g. OFDM symbol index) and the length of the PDSCH (e.g. number of OFDM symbols).

[0086] - PDSCH-to-HARQ_feedback timing indicator: Indicates K1.

[0087] - HARQ process number (4 bits): Indicates the HARQ process ID (Identity) for data (e.g., PDSCH, TB).

[0088] Thereafter, the terminal receives the PDSCH from slot #(n+K0) according to the scheduling information of slot #n, and then transmits UCI via PUCCH in slot #(n1+K1) when the reception of the PDSCH is completed in slot #n1 (where n+K0≦n1). Here, the UCI includes a HARQ-ACK response to the PDSCH. For convenience, in FIG. 5, it is assumed that the SCS for the PDSCH and the SCS for the PUCCH are the same and that slot #n1=slot #n+K0, but the present invention is not limited thereto. If the SCSs are different, K1 is indicated / interpreted based on the SCS of the PUCCH.

[0089] If the PDSCH is configured to transmit up to 1 TB, the HARQ-ACK response consists of 1 bit. If the PDSCH is configured to transmit up to 2 TB, the HARQ-ACK response consists of 2 bits if spatial bundling is not configured and 1 bit if spatial bundling is configured. If the transmission time of the HARQ-ACK for multiple PDSCHs is specified as slot #(n+K1), the UCI transmitted in slot #(n+K1) includes the HARQ-ACK response for multiple PDSCHs.

[0090] Whether or not the UE performs spatial bundling for the HARQ-ACK response is configured for each cell group (e.g., RRC / higher layer signaling). As an example, spatial bundling is configured separately for each of the HARQ-ACK response transmitted via the PUCCH and / or the HARQ-ACK response transmitted via the PUSCH.

[0091] Spatial bundling is supported when the maximum number of TBs (or codewords) that can be received at one time (or scheduled by one DCI) in a corresponding serving cell is two (or more than two) (for example, when the upper layer parameter maxNrofCodeWordsScheduledByDCI corresponds to 2-TB). Meanwhile, more than four layers are used for 2-TB transmission, and up to four layers are used for 1-TB transmission. As a result, when spatial bundling is configured in a corresponding cell group, spatial bundling is performed on serving cells in the corresponding cell group that can schedule more than four layers. A terminal that wishes to transmit a HARQ-ACK response through spatial bundling on a corresponding serving cell can generate a HARQ-ACK response by performing a bit-wise logical AND operation on A / N bits for multiple TBs.

[0092] For example, assuming that a terminal receives DCI scheduling 2-TB and receives 2-TB via PDSCH based on the DCI, a terminal performing spatial bundling can generate a single A / N bit by logically ANDing the first A / N bit for the first TB and the second A / N bit for the second TB. As a result, if both the first TB and the second TB are ACK, the terminal reports an ACK bit value to the base station, and if both TBs are NACK, the terminal reports a NACK bit value to the base station.

[0093] For example, if only 1-TB is actually scheduled on a serving cell that is configured to receive 2-TB, the terminal can generate a single A / N bit by logically ANDing the A / N bit for the 1-TB with a bit value of 1. As a result, the terminal reports the A / N bit for the 1-TB to the base station as is.

[0094] A base station / terminal has multiple parallel DL HARQ processes for DL ​​transmission. Multiple parallel HARQ processes allow DL transmission to be performed continuously while waiting for HARQ feedback for successful or unsuccessful reception of previous DL transmission. Each HARQ process is associated with a HARQ buffer in the Medium Access Control (MAC) layer. Each DL HARQ process manages state variables related to the number of transmissions of MAC Physical Data Blocks (PDUs) in the buffer, HARQ feedback for MAC PDUs in the buffer, current redundancy version, etc. Each HARQ process is distinguished by a HARQ process ID.

[0095] 6 illustrates a PUSCH transmission process. Referring to FIG. 6, a UE detects a PDCCH in slot #n. Here, the PDCCH includes uplink scheduling information (e.g., DCI format 0_0, 0_1). DCI format 0_0, 0_1 includes the following information:

[0096] - Frequency domain resource assignment: Indicates the RB set assigned to the PUSCH.

[0097] - Time domain resource assignment: indicates the slot offset K2, the starting position (e.g., symbol index) and length (e.g., number of OFDM symbols) of the PUSCH within the slot. The starting symbol and length are indicated by the Start and Length Indicator Value (SLIV) or are indicated respectively.

[0098] Thereafter, the terminal transmits a PUSCH in slot #(n+K2) according to the scheduling information of slot #n, where the PUSCH includes a UL-SCH TB.

[0099] Carrier aggregation

[0100] NR can merge multiple uplink / downlink carriers (i.e., carrier merging) to support wider uplink / downlink bandwidth. Carrier merging allows signals to be transmitted / received from multiple carriers. When carrier merging is applied, each carrier (see Figure A2) is called a component carrier (CC). CCs may be adjacent or non-adjacent to each other in the frequency domain. The bandwidth of each CC is defined independently. Asymmetric carrier merging, where the number of UL CCs and the number of DL CCs are different, is also possible.

[0101] - PCell (Primary Cell): In the case of a terminal configured for carrier merging, a cell operating on a primary frequency (e.g., Primary Component Carrier (PCC)) on which the terminal performs an initial connection establishment procedure or initiates a connection re-establishment procedure. In the case of DC (Dual Connectivity), a MCG (Master Cell Group) cell operating on a primary frequency on which the terminal performs an initial connection establishment procedure or initiates a connection re-establishment procedure.

[0102] - SCell (Secondary Cell): For a terminal configured with carrier aggregation, this is a cell that provides radio resources in addition to the special cell.

[0103] - PSCell (Primary SCG Cell): In the case of DC, a Secondary Cell Group (SCG) cell to which the UE randomly connects when performing RRC reconfiguration and synchronization processes.

[0104] - Special Cell (SpCell): In case of DC, the special cell points to a PCell of the MCG or a PSCell of the SCG. Otherwise (i.e., non-DC), the special cell points to a PCell.

[0105] - Serving Cell (ServCell): A cell configured for a terminal in the RRC_CONNECTED state. If CA / DA is not configured, there is only one serving cell (i.e., PCell). If CA / DA is configured, the serving cell indicates a cell set including the special cell and all SCells.

[0106] Meanwhile, the control information can be configured to be transmitted and received only by a specific cell. As an example, UCI is transmitted by a special cell (e.g., PCell). When an SCell (hereinafter, PUCCH-SCell) in which PUCCH transmission is permitted is configured, UCI can also be transmitted by the PUCCH-SCell. As another example, the base station allocates a scheduling cell (set) to reduce the complexity of PDCCH BD (blinding decoding) at the terminal side. For PDSCH reception / PUSCH transmission, the terminal performs PDCCH detection / decoding only in the scheduling cell. Also, the base station transmits PDCCH only in the scheduling cell (set). For example, PDCCH for downlink allocation is transmitted by cell #0 (i.e., scheduling cell), and its PDSCH is transmitted by cell #2 (i.e., scheduled cell) (Cross-Carrier Scheduling, CCS). The scheduling cell (set) is configured by a terminal-specific, terminal-group-specific, or cell-specific manner. The scheduling cell includes a special cell (eg, a PCell).

[0107] A carrier indicator field (CIF) is used for CCS (Cross-Carrier Scheduling). The CIF is semi-statically disabled / enabled by terminal-specific (or terminal group-specific) higher layer (e.g., Radio Resource Control, RRC) signaling. The CIF field is an x-bit field (e.g., x=3) in the PDCCH (i.e., DCI) and is used to indicate the (serving) cell index of the scheduled cell.

[0108] - CIF disabled: There is no CIF in the PDCCH. The PDCCH on the scheduling cell allocates PDSCH / PUSCH resources on the same cell, i.e. the scheduling cell is the same as the scheduled cell.

[0109] - CIF enabled: CIF exists in PDCCH. The scheduling PDCCH allocates PDSCH / PUSCH resources in one cell among multiple cells using CIF. The scheduling cell is the same as or different from the scheduled cell. PDSCH / PUSCH means PDSCH or PUSCH.

[0110] FIG. 7 is a diagram for explaining carrier merging. In FIG. 7, it is assumed that three cells are merged. When CIF is disabled, in each cell, only the PDCCH that schedules its own PDSCH / PUSCH is transmitted (self-carrier scheduling, SCS). On the other hand, when CIF is enabled by terminal-specific (or terminal-group-specific or cell-specific) higher layer signaling and cell A is set as a scheduling cell, cell A transmits not only the PDCCH that schedules cell A's PDSCH / PUSCH, but also the PDCCH that schedules the PDSCH / PUSCH of other cells (i.e., scheduled cells) (cross-carrier scheduling, CCS). In this case, cell B / C does not transmit the PDCCH that schedules its own cell.

[0111] NR-shared spectrum / unlicensed band (NR-U) operation

[0112] FIG. 8 is a diagram illustrating a wireless communication system supporting an unlicensed band. For convenience, a cell operating in a licensed band (hereinafter, L-band) is defined as an LCell, and a carrier of the LCell is defined as a (DL / UL) LCC (Licensed Component Carrier). A cell operating in an unlicensed band (hereinafter, U-band) is defined as an UCell, and a carrier of the UCell is defined as a (DL / UL) UCC (Unlicensed Component Carrier). A cell's carrier refers to the operating frequency (e.g., center frequency) of the cell. A cell / carrier (e.g., Component Carrier, CC) is collectively referred to as a cell.

[0113] When carrier aggregation (CA) is supported, one terminal can transmit and receive signals to and from a base station through multiple aggregated cells / carriers. When multiple CCs are configured in one terminal, one CC is set as a PCC (Primary CC) and the remaining CCs are set as SCCs (Secondary CCs). Specific control information / channels (e.g., CSS PDCCH, PUCCH) are set to be transmitted and received only through the PCC. Data is transmitted and received through the PCC / SCC. FIG. 8(a) illustrates an example in which a terminal and a base station transmit and receive signals through an LCC and a UCC (non-standalone (NSA) mode). In this case, the LCC is set as a PCC and the UCC is set as an SCC. When multiple LCCs are configured in a terminal, one specific LCC is set as a PCC and the remaining LCCs are set as SCCs. FIG. 8(a) corresponds to LAA in a 3GPP LTE system. Figure 8(b) illustrates an example in which a terminal and a base station transmit and receive signals via one or more UCCs without an LCC (SA (Standalone) mode). In this case, one of the UCCs is configured as a PCC, and the remaining UCCs are configured as SCCs. As a result, the NR UCell supports PUCCH, PUSCH, PRACH transmission, etc. In the unlicensed band of the 3GPP NR system, both the NSA mode and the SA mode are supported.

[0114] Unless otherwise stated, the following definitions apply to terms used in this specification.

[0115] - Channel: A channel is a set of consecutive RBs in a shared spectrum where a channel access process is performed. It refers to a carrier or a part of a carrier.

[0116] - Channel Access Procedure (CAP): A procedure for evaluating channel availability based on sensing to determine whether other communication nodes are using the channel before transmitting a signal. The basic unit for sensing is T sl The sensing slot has a duration of 9 us. The base station or the terminal senses the channel during the sensing slot, and the power detected for at least 4 us within the sensing slot is equal to or greater than the energy detection threshold X Thresh If it is smaller, the sensing slot period T sl is considered to be idle. Otherwise, the sensing slot period T sl =9us is considered busy. CAP is also known as LBT (Listen-Before-Talk).

[0117] - Channel occupancy: refers to the corresponding transmission on a channel by a base station / terminal after performing a channel access procedure.

[0118] - Channel Occupancy Time (COT): This refers to the total time that the base station / terminal and any base station / terminal sharing the channel occupancy can transmit on the channel after the base station / terminal performs the channel connection process. When determining the COT, if the transmission gap is 25us or less, the gap period is also counted in the COT. The COT is shared for transmission between the base station and the corresponding terminal.

[0119] - DL transmission burst: is defined as a set of transmissions from a base station with no gaps of more than 16us. Transmissions from a base station separated by gaps of more than 16us are considered to be individual DL transmission bursts. The base station does not sense channel availability within a DL transmission burst and transmits after the gap.

[0120] - UL transmission burst: is defined as a set of transmissions from a terminal with no gaps longer than 16us. Transmissions from a terminal separated by gaps longer than 16us are considered as individual UL transmission bursts. The terminal does not sense channel availability within a UL transmission burst and transmits after the gap.

[0121] - Detection burst: refers to a DL transmission burst that includes a set of signals and / or channels bounded within a (time) window and associated duty cycle. In an LTE-based system, a detection burst is a base station initiated transmission that includes PSS, SSS, and CRS (cell-specific RS), and also includes non-zero power CSI-RS. In an NR-based system, a detection burst is a base station initiated transmission that includes at least SS / PBCH blocks, and also includes CORESET for PDCCH that schedules PDSCH with SIB1, PDSCH carrying SIB1, and / or non-zero power CSI-RS.

[0122] FIG. 9 illustrates a method of occupying resources in an unlicensed band. According to regional regulations for unlicensed bands, a communication node in an unlicensed band must determine whether other communication nodes are using the channel before transmitting a signal. Specifically, a communication node can first perform carrier sensing (CS) before transmitting a signal to determine whether other communication nodes are transmitting signals. A case where it is determined that other communication nodes are not transmitting signals is defined as a case where a clear channel assessment (CCA) is confirmed. If there is a CCA threshold set by a predetermined or higher layer (e.g., RRC) signaling, a communication node determines the channel state as busy when energy higher than the CCA threshold is detected in the channel, and otherwise determines the channel state as idle. For reference, in the Wi-Fi standard (802.11ac), the CCA threshold is specified as -62 dBm for non-Wi-Fi signals and -82 dBm for Wi-Fi signals. If the channel state is determined to be idle, the communication node can start transmitting signals on the UCell. The above series of processes is called LBT (Listen-Before-Talk) or CAP (Channel Access Procedure). LBT and CAP can be used interchangeably.

[0123] Table 6 illustrates the channel access procedure (CAP) supported in NR-U.

[0124] [Table 6]

[0125] Multi-cell Scheduling DCI

[0126] NR supports broad spectrum in various frequency ranges. The re-farming of frequency bands used in previous generations is expected to increase the availability of advanced spectrum for 5G. In particular, for the low frequency band FR1, available spectrum blocks tend to become more fragmented and dispersed. For FR2 bands and some FR1 bands, the available spectrum becomes wider, necessitating the operation of multiple carriers / cells within the band. It is necessary to improve throughput and coverage by using such dispersed spectrum bands or wider bandwidth spectrum in a more power-efficient and flexible manner.

[0127] When scheduling data across multiple cells, including intra-band and inter-band cells, it is important to increase flexibility and spectrum / power efficiency. In the current 5G NR scheduling method, DCI can only schedule PUSCH / PDSCH for one cell. However, it is expected that the need for simultaneous scheduling of multiple cells will increase in the future due to spectrum expansion / modification, etc. In order to reduce control overhead due to scheduling, it is advantageous to schedule PUSCH / PDSCH for multiple cells using one DCI.

[0128] Thus, in future, in carrier aggregation (CA) situations where multiple cells are configured, in order to reduce the DCI overhead for PDSCH / PUSCH scheduling, Rel-18 will consider a multi-cell scheduling scheme that simultaneously schedules multiple (serving) cells / CCs (and thus PDSCH / PUSCH transmissions) with a single DCI.

[0129] Here, a method for controlling / handling fields constituting the DCI (multi-cell DCI) performing the above-mentioned multi-cell scheduling and the size of the DCI is proposed. For convenience, the operation of multi-cell scheduling for PDSCH transmission will be mainly described, but the operation principle of the proposed method is also similarly applied to the case of multi-cell scheduling for PUSCH transmission. Hereinafter, a cell may refer to a BWP configured / instructed (active) for the cell.

[0130] Hereinafter, the multi-cell scheduling DCI is also referred to as a multi-cell DCI or simply DCI, and includes at least one of a DL grant DCI for scheduling a PDSCH and a UL grant DCI for scheduling a PUSCH.

[0131] [1] DCI field configuration for each scheduled cell within a multi-cell DCI

[0132] When multiple cells are scheduled by the same multi-cell DCI, the corresponding DCI field is arranged / configured for each cell in the order of cell index for the same DCI field.

[0133] As an example, the DCI fields for cells with lower cell indexes are placed / configured at lower bit indices (within the DCI).

[0134] On the other hand, one DCI field (which is applied commonly to the cells belonging to the subgroup) is configured for each cell subgroup consisting of (single or) multiple cells. In this case, the lowest cell index among the cells belonging to each subgroup is compared, and the DCI field for the subgroup to which the lower cell index belongs is placed / configured at a lower bit index (within the DCI).

[0135] For example, in FIG. 10, it is assumed that a plurality of cells configured in a terminal include Cell A to Cell M, the cell index of Cell B is greater than the cell index of Cell A, the cell index of Cell C is greater than the cell index of Cell B, and the cell index of Cell M is greater than the cell index of Cell C. First, referring to FIG. 10(a), bits for a plurality of cells are included in one DCI field. In one DCI field, bits are arranged in the order of Cell A, Cell B, Cell C, ..., Cell M. Referring to FIG. 10(b), the DCI includes DCI fields X for each of a plurality of cells. In the DCI, each DCI field X is arranged in the order of Cell A, Cell B, Cell C, ..., Cell M. Meanwhile, the fact that the bit / DCI field for a lower index cell is arranged before the cell with a higher index does not necessarily mean that the bit / DCI field of the cell is arranged consecutively, but may be arranged discontinuously within a range where a positional front / back relationship is maintained. For example, referring to FIG. 10(c), the DCI includes DCI fields X and Y for each of a plurality of cells. In the DCI, the DCI fields X and Y are arranged in the order of Cell A, Cell B, Cell C, ..., and Cell M, but are not limited thereto. For example, referring to FIG. 10(d), the DCI includes DCI fields X and Y for each of a plurality of cells. In the DCI, the DCI fields X are arranged in the order of Cell A, Cell B, Cell C, ..., and Cell M, and then the DCI fields Y are arranged (continuously / or non-continuously) in the order of Cell A, Cell B, Cell C, ..., and Cell M. In one DCI, application of (a) to (d) may be different for each DCI field. For example, in one DCI, any one of (a) to (d) is applied to DCI field 1, and any other one of (a) to (d) is applied to DCI field 2.

[0136] The DCI field may include, but is not limited to, at least one of an MCS field, an NDI field, an RV field, and / or a HARQ process ID (HARQ ID) field.

[0137] The DCI field may include, but is not limited to, at least one of a frequency domain resource assignment / allocation (FDRA) field and / or a time domain RA (TDRA) field and / or a TPC (for PUSCH) field.

[0138] The cell index is, for example, a serving cell index or a cell index (on the RRC configuration) used when configuring the combination of candidate cells for multi-cell DCI scheduling.

[0139] [2] Restrictions on (maximum) payload size of multi-cell DCI

[0140] 1) Proposal 1

[0141] Regardless of the maximum number of TBs that can be transmitted via a single PDSCH configured for each cell (which is defined as N_t for convenience, and is set to N_t=1 or N_t=2, for example) and the number of cells scheduled by the same multi-cell DCI (which is defined as N_c for convenience), or the cell combination, the maximum value of the total number of TBs scheduled to multiple cells by a single multi-cell DCI is limited to less than N_max (for example, N_max is set by the base station, or is determined to be the maximum number of cells that can be scheduled by the multi-cell DCI, or N_max=4).

[0142] As an example, up to N_max fields may be configured in the multi-cell DCI for the MCS and / or NDI and / or RV and / or HARQ ID fields (respectively).

[0143] As an example, if the sum of the N_t values ​​set for each of the N_c cells scheduled with the same multi-cell DCI exceeds the N_max value, a rule is defined such that all N_max TBs are allocated / scheduled to those N_c cells in the manner of cell index first - TB index second.

[0144] For example, if N_c=3, and the three cells (index=0, 1, 2) all have N_t=2 and N_max=4, then 2 / 1 / 1 TBs are assigned / scheduled to cell indexes 0 / 1 / 2, respectively.

[0145] The cell index is, for example, a serving cell index or a cell index (in the RRC configuration) used when configuring the combination of candidate cells for multi-cell DCI scheduling.

[0146] 2) Proposal 2

[0147] If the number of cells scheduled by the multi-cell DCI is less than or equal to L (e.g., L=1 or L=2), up to N_t TBs configured for that cell can be scheduled, whereas if the number of cells scheduled by the multi-cell DCI exceeds L, only a single TB is limited to be scheduled for all of the cells.

[0148] As an example, the maximum number N_max of the total number of TBs (scheduled to multiple cells) by a single multi-cell DCI is determined to be the maximum number of cells that can be scheduled by the multi-cell DCI.

[0149] As an example, up to N_max fields may be configured in the multi-cell DCI for the MCS and / or NDI and / or RV and / or HARQ ID fields (respectively).

[0150] [3] Handling invalid cells scheduled in multi-cell DCI

[0151] 1) If an invalid cell is included among the cells scheduled / indicated by the multi-cell DCI, PDSCH / PUSCH transmission / reception is not performed for the invalid cell, and PDSCH / PUSCH transmission / reception is performed only for the other cells.

[0152] In this case, in the multi-cell DCI, the DCI fields corresponding to the disabled cells (e.g., MCS, NDI, RV, HARQ ID, FDRA, TDRA, TPC (for PUSCH), antenna port, transmission configuration indication, SRS resource indicator, precoding information and number of layers, DMRS sequence initialization, PTRS-DMRS association, VRB-to-PRB mapping, PRB bundling size indicator, rate matching indicator, ZP CSI-RS trigger, SRS request, frequency hopping flag, ChannelAccess-CPext-CAPC (for PUSCH), open loop power control parameter set indicator, and disabled symbol pattern indicator) are not configured and are omitted (i.e., DCI fields are configured sequentially (according to the cell index value / order) only for the other cells), or the corresponding DCI fields are configured (according to the cell index value / order) for the disabled cells, but are omitted (e.g., the first active DL / UL BWP specified by the parameters firstActiveDownlinkBWP / firstActiveUplinkBWP). The DCI field is configured based on the parameters / values ​​set in the BWP or the most recently activated DL / UL BWP (excluding dormant BWP), or is reserved with a predefined bit value, or the terminal operates to ignore the field.

[0153] As an example, in configuring the HARQ-ACK feedback payload corresponding to the multi-cell DCI, the HARQ-ACK bit corresponding to the invalid cell is omitted without being configured (i.e., the HARQ-ACK bit is configured sequentially (according to the cell index value / order) only for the other cells), or the HARQ-ACK bit corresponding to the invalid cell is configured (according to the cell index value / order) but the bit is mapped to a NACK. For example, assuming that {Cell A, Cell B, Cell C} are scheduled together by one DCI and Cell B is an invalid cell, the HARQ-ACK is configured as {A / N(s) for (TBs of) Cell A, A / N(s) for (TBs of) Cell C (and / or NACK(s) for remaining bit(s))}, or the HARQ-ACK is configured as {A / N(s) for (TBs of) Cell A, NACK(s) for (TBs of) Cell B, A / N(s) for (TBs of) Cell C}.

[0154] The invalid cell is a deactivated Scell ​​and / or a cell operating as a dormant BWP and / or a cell in which the PDSCH (PUSCH) resource indicated by the multi-cell DCI overlaps in time with a semi-static UL (DL) symbol and / or a cell in which the frequency resource of the PDSCH (PUSCH) assigned by the multi-cell DCI is set to an invalid value (e.g., a bitmap form in which all bits are '0' or a resource indication (RIV) form in which all bits are '1'). A DCI may correspond to a cell indicated by a DCI in a 0 or 1 (e.g., SLIV type in which all bits are '1') and / or a cell indicated by a multi-cell DCI in which the time resources of the PDSCH (PUSCH) allocated by the multi-cell DCI are set to an invalid value (e.g., in a SLIV type in which all bits are '1') and / or a cell indicated by a multi-cell DCI in which a TB disabling operation is instructed for all TBs (of the cell) and / or a cell operating in a DRX-off state (without PDCCH monitoring) and / or a cell corresponding to a predetermined time period (or a predetermined BWP) set / instructed to stop a series of transmission / reception operations for energy / power saving of the base station, etc. For example, assuming that information for resource allocation (e.g., FDRA field) in the DCI is configured separately for each scheduled cell, a cell in which all bits of the information for resource allocation are set to 0 or 1 (i.e., an invalid value for resource allocation) is an invalid cell (a cell that is not actually scheduled).

[0155] 2) Meanwhile, in order to reduce the complexity of operations related to the multi-cell DCI configuration and scheduling, a constraint is imposed that the SCSs used / applied to cells belonging to each cell combination (for convenience, referred to as a "co-scheduled cell set") scheduled simultaneously from the DCI must all be the same value. If the SCSs used / applied between cells belonging to a specific co-scheduled cell set (active BWPs configured / indicated for each of the cells) have different values, PDSCH / PUSCH transmission / reception is performed only for cells for which a specific (valid) SCS is used / applied, and PDSCH / PUSCH transmission / reception is omitted for cells for which other (invalid) SCSs are used / applied. In this case, the cell for which the invalid SCS is used / applied corresponds to the invalid cell (thus, the DCI field and HARQ-ACK configuration method corresponding to the invalid cell described above is applied to the cell for which the invalid SCS is used / applied).

[0156] In the case of the above-mentioned valid SCS, it is either pre-set by the RRC, etc. (e.g., a separate valid SCS value is set for each co-scheduled cell set, or one valid SCS value common to all co-scheduled cell sets is set), or it is determined based on a predetermined rule (e.g., Alt 1) it is determined to be the SCS value used / applied to a specific cell (e.g., the lowest cell index) belonging to the co-scheduled cell set, or Alt 2) it is determined to be the minimum / maximum value among the SCS used / applied to the cells belonging to the co-scheduled cell set, or Alt 3) it is determined to be the SCS value used / applied to the most common cell among the cells belonging to the co-scheduled cell set (if there are multiple SCS values ​​used / applied to the most common cell, the value determined by applying Alt 1 / 2 to the multiple SCS values).

[0157] Alternatively, if the SCS used / applied between cells belonging to a particular co-scheduled cell set (active BWP configured / indicated for that cell) has different values, scheduling by multi-cell DCI is not allowed for that co-scheduled cell set (the terminal does not expect scheduling for that co-scheduled cell set), and thus the terminal can omit DCI monitoring (blind decoding) operation for PDCCH candidates (search space) configured / corresponding to that co-scheduled cell set scheduling (DCI transmission).

[0158] [4] TB disabling for PDSCH scheduled in multi-cell DCI

[0159] 1) Conventional operation

[0160] In the case of scheduling based on a conventional single-cell DCI, in a situation where the maximum number of TBs that can be transmitted via one PDSCH is set to two (e.g., two TB transmissions are scheduled via one PDSCH), when a combination of a specific MCS index (e.g., 26) and a specific RV index (i.e., RV ID) (e.g., 1) is indicated by the DCI, an operation is specified to disable the transmission / reception of the corresponding specific TB index.

[0161] 2) Suggested action

[0162] If multiple cells are scheduled by the multi-cell DCI, RV index 0 or X (e.g., X=2) is indicated by a 1-bit RV for each cell (TB), and if a single cell is scheduled by the multi-cell DCI (assuming that scheduling is possible), RV index 0 / 1 / 2 / 3 is indicated for that cell by a 2-bit RV.

[0163] 3) Proposal 1

[0164] For multiple cells scheduled by the multi-cell DCI, the TB index indicated by the combination of a specific MCS index Z (e.g., Z=26) and the RV index X for each cell is treated as disabled and the PDSCH is received.

[0165] For the cells for which the above conditions are not met for the scheduled cells, the PDSCH is received under the assumption that there is no TB disabling.

[0166] 4) Proposal 2

[0167] When the combination of MCS index Z and RV index X is indicated for the same TB index of all cells (set to N_t=2) for multiple cells scheduled by the multi-cell DCI, the TB index operates to receive the PDSCH as if it were disabled for all cells (set to N_t=2).

[0168] The method is applied only when all cells scheduled by the multi-cell DCI are cells set to N_t=2, or is applied only to cells scheduled by the multi-cell DCI that are set to N_t=2.

[0169] If the condition is not met for the scheduled cells, it operates to receive the PDSCH under the assumption that there is no TB disabling.

[0170] 5) Proposal 3

[0171] If only a single cell is scheduled by the multi-cell DCI (as in the conventional method), the TB index indicated by the combination of the MCS index Z and a specific RV index Y (e.g., Y=1) is considered to be disabled, and if multiple cells are scheduled by the multi-cell DCI, the PDSCH is always received under the assumption that there is no TB disablement.

[0172] [5] Handling of out-of-order behavior for multi-cell DCI scheduling

[0173] 1) Conventional operation

[0174] First, the constraints on out-of-order PDSCH / PUSCH / PUCCH scheduling defined in the current standard in relation to single cell scheduling are briefly described below.

[0175] - For any two HARQ IDs in the same cell, when a specific PDSCH #1 is scheduled by a specific PDCCH #1, the terminal operates in such a way as not to expect a situation in which another PDSCH #2 having a starting symbol earlier than the ending symbol of PDSCH #1 is scheduled by another PDCCH #2 having an ending symbol later than the ending symbol of PDCCH #1 (for convenience, this is referred to as PDSCH Out-Of-Order, or "PDSCH OOO").

[0176] - For any two HARQ IDs in the same cell, when a specific PUSCH #1 is scheduled by a specific PDCCH #1, the terminal operates in such a way as not to expect a situation in which another PUSCH #2 having a start symbol earlier than the end symbol of PUSCH #1 is scheduled by another PDCCH #2 having an end symbol later than the end symbol of PDCCH #1 (for convenience, this is referred to as "PUSCH OOO").

[0177] - For a given cell, when HARQ-ACK feedback corresponding to a specific PDSCH #1 is instructed to be transmitted by a specific slot #A, the terminal operates in such a way as not to expect a situation in which HARQ-ACK feedback corresponding to another PDSCH #2, which starts later than PDSCH #1, is instructed to be transmitted by a slot beyond slot #A (for convenience, this is referred to as "PUCCH OOO").

[0178] 2) Proposal

[0179] According to an embodiment, the proposed out-of-order PDSCH / PUSCH / PUCCH scheduling constraints in relation to multi-cell scheduling include any one of the following:

[0180] A. For multiple PDSCHs #1 on multiple cells scheduled by the same multi-cell DCI PDCCH #1, the terminal operates not to expect a situation in which the relationship between the timing of that (multi-cell DCI) PDCCH #1 and PDSCH #1 and the timing of the other PDCCHs #2 and PDSCH #2 on at least one of the multiple cells is scheduled to correspond to the PDSCH OOO, and if scheduled to correspond to PDSCH OOO on at least one cell as described above, the terminal can discard / ignore the multi-cell DCI and / or skip reception of multiple PDSCHs on multiple cells scheduled by that DCI. For example, to describe PDSCH OOO in the context of multi-cell scheduling, (i) at least one of DCI #1 and DCI #2 is a multi-cell scheduling DCI, (ii) the last symbol of DCI #2 is located after the last symbol of DCI #1, (iii) DCI #1 schedules M PDSCHs #1 {PDSCH#1-1, PDSCH#1-1,,,, ,PDSCH#1-M} (on M cells), (iv) DCI #2 schedules N PDSCHs #2 {PDSCH#2-1, PDSCH#2-1,,,,,PDSCH#2-N} (on N cells), and N PDSCHs #2 {PDSCH#2-1, PDSCH#2-1,,,,, ,PDSCH#2-N} are located before the last symbol of (any one of) M PDSCHs #1 {PDSCH#1-1, PDSCH#1-1,,,,, ,PDSCH#1-M}. , PDSCH#2-N} is located, the PDSCH is OOO. Each of M and N is an integer of 1 or more.

[0181] B. For multiple PUSCHs #1 on multiple cells scheduled by the same multi-cell DCI PDCCH #1, the terminal operates not to expect a situation in which the relationship between the timing of that (multi-cell DCI) PDCCH #1 and PUSCH #1 and the timing of the other PDCCHs #2 and PUSCH #2 on at least one of the multiple cells is scheduled to correspond to the PUSCH OOO, and if scheduled to correspond to PUSCH OOO on at least one cell as described above, the terminal can discard / ignore the multi-cell DCI and / or drop transmissions for multiple PUSCHs on multiple cells scheduled by that DCI. For example, to describe PUSCH OOO in the context of multi-cell scheduling, (i) at least one of DCI #1 and DCI #2 is a multi-cell scheduling DCI, (ii) the last symbol of DCI #2 is located after the last symbol of DCI #1, (iii) DCI #1 schedules M PUSCHs #1 {PUSCH#1-1, PUSCH#1-1,,,,, ,PUSCH#1-M} (on M cells), (iv) DCI #2 schedules N PUSCHs #2 {PUSCH#2-1, PUSCH#2-1,,,,, ,PUSCH#2-N} (on N cells), and N PUSCHs #2 {PUSCH#2-1, When the start symbol of any one of the PUSCH#2-1,,,,, ,PUSCH#2-N} is located, the PUSCH is OOO. Each of M and N is an integer of 1 or more.

[0182] C. For multiple PDSCH #1 on multiple cells scheduled by the same multi-cell DCI, the terminal operates not to expect a situation in which the relationship between the timing of the HARQ-ACK corresponding to that PDSCH #1 and the timing of the HARQ-ACK corresponding to the other PDSCH #2 on at least one of the multiple cells is scheduled to correspond to the PUCCH OOO, and if scheduled to correspond to PUCCH OOO on at least one cell as described above, the terminal can discard / ignore the multi-cell DCI and / or skip reception for multiple PDSCHs on multiple cells scheduled by that DCI and / or drop HARQ-ACK transmission for multiple PDSCHs on multiple cells scheduled by that DCI. PDSCH #2 is associated with a multi-cell scheduling DCI or associated with a single-cell scheduling DCI. i) For example, assume that M PDSCHs #1 {PDSCH #1-1, PDSCH #1-2, ..., PDSCH #1-M} (M is an integer equal to or greater than 1) are scheduled by multi-cell scheduling DCI #1, N PDSCHs #2 {PDSCH #2-1, PDSCH #2-2, ..., PDSCH #2-N} (N is an integer equal to or greater than 1) are scheduled by multi-cell scheduling DCI #2, and at least one of the N PDSCHs #2 starts later than at least one of the M PDSCHs #1. If the slots of HARQ-ACK for the N PDSCHs #2 are earlier than the slots of HARQ-ACK for the M PDSCHs #1, PUCCH OOO is generated.ii) As another example, assume that M PDSCHs #1 {PDSCH #1-1, PDSCH #1-2, ..., PDSCH #1-M} (M is an integer equal to or greater than 1) are scheduled by multi-cell scheduling DCI #1, PDSCH #2 is scheduled by single-cell scheduling DCI #2, and PDSCH #2 starts later than at least one of the M PDSCHs #1. If the slot of the HARQ-ACK for PDSCH #2 comes before the slot of the HARQ-ACK for the M PDSCHs #1, then PUCCH OOO occurs. iii) As another example, assume that M PDSCHs #1 {PDSCH #1-1, PDSCH #1-2, ..., PDSCH #1-M} (M is an integer equal to or greater than 1) are scheduled by multi-cell scheduling DCI #1, PDSCH #2 is scheduled by single-cell scheduling DCI #2, and at least one of the M PDSCHs #1 starts later than PDSCH #2. If the slots of HARQ-ACK for M PDSCHs #1 come before the slots of HARQ-ACK for PDSCH #2, then PUCCH OOO occurs.

[0183] [6] DL SPS / UL CG activation / release ( / retransmission) operation based on multi-cell DCI

[0184] 1) When the multi-cell DCI is transmitted / received based on CS (configured scheduling)-RNTI (scrambling applied thereto), for multiple cells indicated by the DCI (in a specific (e.g., CIF or new) field in the DCI), the terminal checks whether a combination of specific fields (e.g., HARQ process ID, RV, MCS, all or part of frequency domain resource allocation) corresponding to each cell satisfies an indication condition for activation and / or release (and / or retransmission) related to SPS / CG (see Section 10.2 of 3GPP TS 38.213 V16.2.0), and based on this, the terminal performs an operation indicated (validated) for each cell.

[0185] For example, only SPS / CG activation operation is instructed for all of a plurality of cells (all or part) indicated by the same (CS-RNTI based) multi-cell DCI, or only SPS / CG release operation is instructed for all of the plurality of cells (all or part), or SPS / CG activation operation is instructed for certain cells among the plurality of cells (all or part), and SPS / CG release operation is instructed for the other cells.

[0186] Alternatively, it may be specified that only the SPS / CG activation operation is instructed for all of the multiple cells (all or part) indicated by the same (CS-RNTI-based) multi-cell DCI, or that only the SPS / CG release operation is instructed for all of the multiple cells (all or part).

[0187] 2) Alternatively, it is specified that only when only one cell is indicated by the (CS-RNTI based) multi-cell DCI, it is possible to indicate activation and / or release (and / or retransmission) related to SPS / CG (for that cell), and when multiple cells are indicated by the multi-cell DCI, it is specified that no indication of activation and / or release (and / or retransmission) related to SPS / CG is allowed (none), or only retransmission scheduling is possible (no indication of activation and / or release is allowed) related to SPS / CG.

[0188] Meanwhile, for a specific cell combination (consisting of multiple cells) that can be indicated / scheduled by the multi-cell DCI, if CS-RNTI (i.e., SPS / CG) is configured for some cells (for convenience, referred to as "cells with CS-RNTI") belonging to the cell combination, and CS-RNTI (i.e., SPS / CG) is not configured for the other cells (for convenience, referred to as "cells without CS-RNTI"),

[0189] Opt 1) When the specific cell combination is indicated by the CS-RNTI-based multi-cell DCI, for cells that do not include the CS-RNTI, perform transmission / reception operations in a state in which it is assumed that there is no PDSCH / PUSCH scheduling; or

[0190] Opt 2) For the particular cell combination, indication / scheduling by multi-cell DCI based on CS-RNTI is not possible / allowed (indication / scheduling by multi-cell DCI based on C-RNTI is not possible / allowed).

[0191] [7] Determination and restriction of the (maximum) payload size of multi-cell DCI

[0192] The (maximum) payload size of the multi-cell DCI is determined to be the maximum value among all cell combinations that can be scheduled by the DCI, when the sum of the sizes of each field corresponding to the cell combination (each cell in the cell combination) is calculated (for each cell combination). As a specific example, referring to FIG. 11, it is assumed that a total of N cells from Cell #1 to Cell #N are configured in the terminal, and there are M cell combinations that can be scheduled together by the multi-cell scheduling DCI. For example, M cell combinations are configured in the terminal by the base station. It is assumed that the total DCI field bits required for scheduling case 1 are (minimum) all A-bits, the total DCI field bits required for scheduling case 2 are (minimum) all B-bits, the total DCI field bits required for scheduling case 3 are (minimum) all C-bits, and the total DCI field bits required for scheduling case M are (minimum) all K-bits. To cover cases 1 to M, the payload of the multi-cell scheduling DCI is configured based on Max{A, B, C,..., K}-bits. For example, the payload of the multi-cell scheduling DCI is set to be equal to or greater than Max{A, B, C,..., K}-bits.

[0193] The terminal does not have to expect / assume that the payload size of the multi-DCI determined as described above will be set (the cell combination to be scheduled for the multi-cell DCI and / or the transmission parameters for each cell, etc.) such that it exceeds the maximum number of bits N (e.g., N=140) that a particular encoding method (e.g., a polar code) can apply / support. If this occurs, the terminal will not perform monitoring / decoding operations for the multi-cell DCI, or will remove some of the bits (corresponding fields) that are specific (e.g., have a high index) configured / set within the DCI, and perform monitoring / decoding operations for the DCI with the payload size of the DCI adjusted to the number of bits N.

[0194] 12 is a diagram illustrating an example of signal reception by a terminal based on at least a portion of the above-described embodiment. The above content may be referred to for understanding FIG. 12 without any special explanation.

[0195] Referring to FIG. 12, the UE may monitor physical downlink control channel (PDCCH) candidates (1205).

[0196] The UE may detect downlink control information (DCI) through monitoring of the PDCCH candidates (1210).

[0197] The DCI may support multi-cell scheduling based on cell combinations regarding a plurality of cells configured in the UE. A payload size of the DCI may be determined based on a first cell combination in which a total number of bits required for co-scheduled cells from among the cell combinations.

[0198] The payload of the DCI is determined based on the combined size of all DCI fields for the first cell combination.

[0199] The cells co-scheduled by the DCI are indicated to be one of the cell combinations. The DCI includes information indicating one of the cell combinations.

[0200] The DCI includes information on a first DCI field for each of a first cell and a second cell that are scheduled together. Based on the first cell having a lower serving cell index than the second cell, the information on the first DCI field for the first cell is arranged in the DCI before the information on the first DCI field for the second cell. For example, the first DCI field may include, but is not limited to, at least one of a modulation and coding scheme (MCS) field, a new data indicator (NDI) field, a redundancy version (RV) field, a hybrid automatic repeat request (HARQ) process ID field, a frequency domain resource allocation (FDRA) field, a time domain resource allocation (TDRA) field, and a transmission power command (TPC) field for a physical uplink shared channel (PUSCH).

[0201] Among the cells co-scheduled by the DCI, transmission (e.g., PUSCHs for UL grant DCI) or reception (e.g., PDSCHs for DL ​​grant DCI) of scheduled signals is performed only for the other cells except for at least one inactive cell. The at least one inactive cell includes, but is not limited to, at least one of a deactivated SCell (secondary cell), a cell operating as a Dormant BWP (bandwidth part), a cell whose resource allocated by the DCI overlaps with a semi-static resource whose UL (uplink) / DL (downlink) directions are set to be different, and a cell whose frequency resource information indicated by the DCI is not valid. As an example, assuming that the DCI is a DL grant DCI that schedules a PDSCH, hybrid automatic repeat request-acknowledgement (HARQ-ACK) information for a PDSCH is configured for the other cells except for the at least one inactive cell, or configured to include negative acknowledgement (NACK) information for the at least one inactive cell. In the DCI, a DCI field value for the at least one non-valid cell is set based on information about a particular BWP (bandwidth part).

[0202] 13 is an example of a signal transmission by a base station based on at least a part of the above-described embodiment. The above content can be referred to for understanding FIG. 13 without special description.

[0203] Referring to FIG. 13, the base station generates downlink control information (DCI) (1305).

[0204] The base station transmits (1310) the DCI to the terminal based on at least one of the terminal's physical downlink control channel (PDCCH) candidates.

[0205] The DCI supports multi-cell scheduling based on a cell combination for a plurality of cells configured in the terminal, and a payload size of the DCI is determined based on a first cell combination among the cell combinations, which has a maximum total number of DCI bits required for co-scheduled cells.

[0206] The payload of the DCI is determined based on the combined size of all DCI fields for the first cell combination.

[0207] The cells co-scheduled by the DCI are indicated to be one of the cell combinations. The DCI includes information indicating one of the cell combinations.

[0208] The DCI includes information on a first DCI field for each of a first cell and a second cell scheduled together. Based on the first cell having a lower serving cell index than the second cell, the information on the first DCI field for the first cell is arranged in the DCI before the information on the first DCI field for the second cell. For example, the first DCI field may include, but is not limited to, at least one of a modulation and coding scheme (MCS) field, a new data indicator (NDI) field, a redundancy version (RV) field, a hybrid automatic repeat request (HARQ) process ID field, a frequency domain resource allocation (FDRA) field, a time domain resource allocation (TDRA) field, and a transmission power command (TPC) field for a physical uplink shared channel (PUSCH).

[0209] Among the cells co-scheduled by the DCI, only the other cells except the at least one inactive cell receive (e.g., PUSCHs for UL grant DCI) or transmit (e.g., PDSCHs for DL ​​grant DCI) the scheduled signal. The at least one inactive cell includes, but is not limited to, at least one of a deactivated SCell (secondary cell), a cell operating as a Dormant BWP (bandwidth part), a cell whose resource allocated by the DCI overlaps with a semi-static resource whose UL (uplink) / DL (downlink) directions are set to be different, and a cell whose frequency resource information indicated by the DCI is not active. As an example, assuming that the DCI is a DL grant DCI that schedules a PDSCH, hybrid automatic repeat request-acknowledgement (HARQ-ACK) information for the PDSCH is configured for the other cells except the at least one inactive cell, or is configured to include negative acknowledgement (NACK) information for the at least one inactive cell. In the DCI, a DCI field value for the at least one non-valid cell is set based on information about a particular BWP (bandwidth part).

[0210] FIG. 14 illustrates a communication system 1 to which the present invention can be applied.

[0211] Referring to FIG. 14, the communication system 1 includes wireless devices, base stations, and networks. Here, the wireless devices refer to devices that communicate using wireless connection technology (e.g., 5G NR, LTE), and are also referred to as communication / wireless / 5G devices. The wireless devices include, but are not limited to, a robot 100a, vehicles 100b-1, 100b-2, an XR (eXtended Reality) device 100c, a handheld device (Hand-held Device) 100d, a home appliance 100e, an IoT (Internet of Thing) device 100f, and an AI server / device 400. For example, the vehicles include vehicles equipped with wireless communication functions, autonomous vehicles, vehicles capable of inter-vehicle communication, and the like. Here, the vehicles include UAVs (Unmanned Aerial Vehicles) (e.g., drones). XR devices include Augmented Reality (AR) / Virtual Reality (VR) / Mixed Reality (MR) devices, and are embodied in the form of Head-Mounted Devices (HMDs), Head-Up Displays (HUDs) mounted on vehicles, TVs, smartphones, computers, wearable devices, home appliances, digital billboards, vehicles, robots, etc. Portable devices include smartphones, smart pads, wearable devices (e.g., smart watches, smart glasses), computers (e.g., notebook computers, etc.), etc. Home appliances include TVs, refrigerators, washing machines, etc. IoT devices include sensors, smart meters, etc. For example, base stations and networks may also be embodied as wireless devices, and a specific wireless device 200a may operate as a base station / network node for other wireless devices.

[0212] The wireless devices 100a to 100f are connected to a network 300 via a base station 200. AI (Artificial Intelligence) technology is applied to the wireless devices 100a to 100f, and the wireless devices 100a to 100f are connected to an AI server 400 via the network 300. The network 300 is configured using a 3G network, a 4G (e.g., LTE) network, or a 5G (e.g., NR) network. The wireless devices 100a to 100f can communicate with each other via the base station 200 / network 300, but can also communicate directly without going through the base station / network (e.g., sidelink communication). For example, the vehicles 100b-1 and 100b-2 can communicate directly (e.g., V2V (Vehicle to Vehicle) / V2X (Vehicle to everything) communication). Also, an IoT device (e.g., a sensor) can directly communicate with another IoT device (e.g., a sensor) or another wireless device 100a to 100f.

[0213] Wireless communication / connections 150a, 150b, and 150c are performed between the wireless devices 100a to 100f / base stations 200 and the base stations 200. Here, the wireless communication / connections are performed by various wireless connection technologies such as uplink / downlink communication 150a and sidelink communication 150b (or D2D communication) and communication between base stations 150c (e.g., relay, IAB (Integrated Access Backhaul) (e.g., 5G NR). Through the wireless communication / connections 150a, 150b, and 150c, the wireless devices and base stations, and the base stations and base stations can transmit / receive wireless signals to each other. For example, the wireless communication / connections 150a, 150b, and 150c can transmit / receive signals via various physical channels. To this end, based on various proposals of the present invention, any one of various configuration information setting processes for transmitting / receiving wireless signals, various signal processing processes (e.g., channel coding / decoding, modulation / demodulation, resource mapping / demapping, etc.), and resource allocation processes is performed.

[0214] FIG. 15 illustrates a wireless device to which the present invention can be applied.

[0215] 15, a first wireless device 100 and a second wireless device 200 transmit and receive wireless signals using various wireless access technologies (e.g., LTE, NR), where {first wireless device 100, second wireless device 200} corresponds to {wireless device 100x, base station 200} and / or {wireless device 100x, wireless device 100x} in FIG.

[0216] 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 is configured to control the memory 104 and / or the transceiver 106 to implement the descriptions, functions, procedures, suggestions, methods, and / or flowcharts disclosed herein. For example, the processor 102 processes information in the memory 104 to generate a first information / signal, and then transmits a wireless signal including the first information / signal via the transceiver 106. The processor 102 also receives a wireless signal including a second information / signal via the transceiver 106, and then stores information obtained from signal processing of the second information / signal in the memory 104. The memory 104 is coupled to the processor 102 and stores various information related to the operation of the processor 102. For example, the memory 104 stores software code including instructions for performing some or all of the processes controlled by the processor 102 or for performing the descriptions, functions, procedures, suggestions, methods, and / or flowcharts disclosed herein. Here, the processor 102 and memory 104 are part of a communication modem / circuit / chip designed to implement a wireless communication technology (e.g., LTE, NR). The transceiver 106 is coupled to the processor 102 and transmits and / or receives wireless signals via one or more antennas 108. The transceiver 106 includes a transmitter and / or a receiver. The transceiver 106 may also be referred to as an RF (radio frequency) unit. In this specification, a wireless device may also refer to a communication modem / circuit / chip.

[0217] 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 is configured to control the memory 204 and / or the transceiver 206 to implement the descriptions, functions, procedures, suggestions, methods, and / or flowcharts disclosed herein. For example, the processor 202 processes information in the memory 204 to generate a third information / signal, and then transmits a wireless signal including the third information / signal via the transceiver 206. The processor 202 also receives a wireless signal including a fourth information / signal via the transceiver 206, and then stores information obtained from the signal processing of the fourth information / signal in the memory 204. The memory 204 is coupled to the processor 202 and stores various information related to the operation of the processor 202. For example, the memory 204 stores software code including instructions for performing some or all of the processes controlled by the processor 202 or for performing the descriptions, functions, procedures, suggestions, methods, and / or flowcharts disclosed herein. Here, the processor 202 and memory 204 are part of a communication modem / circuit / chip designed to implement a wireless communication technology (e.g., LTE, NR). The transceiver 206 is coupled to the processor 202 and transmits and / or receives wireless signals via one or more antennas 208. The transceiver 206 includes a transmitter and / or a receiver. The transceiver 206 may also be referred to as an RF unit. In this specification, a wireless device may also refer to a communication modem / circuit / chip.

[0218] The hardware elements of the wireless device 100, 200 are described in more detail below. One or more protocol layers may be implemented by one or more processors 102, 202, without limitation. For example, the one or more processors 102, 202 may implement one or more layers (e.g., functional layers such as PHY, MAC, RLC, PDCP, RRC, SDAP). The one or more processors 102, 202 may generate one or more Protocol Data Units (PDUs) and / or one or more Service Data Units (SDUs) according to the descriptions, functions, procedures, suggestions, methods, and / or flowcharts disclosed herein. The one or more processors 102, 202 may generate messages, control information, data, or information according to the descriptions, functions, procedures, suggestions, methods, and / or flowcharts disclosed herein. The one or more processors 102, 202 may generate and provide signals (e.g., baseband signals) including PDUs, SDUs, messages, control information, data or information according to the functions, procedures, suggestions, and / or methods disclosed herein to the one or more transceivers 106, 206. The one or more processors 102, 202 may receive signals (e.g., baseband signals) from the one or more transceivers 106, 206 and derive the PDUs, SDUs, messages, control information, data or information according to the descriptions, functions, procedures, suggestions, methods and / or flowcharts disclosed herein.

[0219] The one or more processors 102, 202 may also be referred to as controllers, microcontrollers, microprocessors, or microcomputers. The one or more processors 102, 202 may be implemented using hardware, firmware, software, or a combination thereof. As an example, the one or more processors 102, 202 may include one or more application specific integrated circuits (ASICs), one or more digital signal processors (DSPs), one or more digital signal processing devices (DSPDs), one or more programmable logic devices (PLDs), or one or more field programmable gate arrays (FPGAs). The descriptions, functions, procedures, suggestions, methods, and / or flowcharts disclosed herein may be implemented using firmware or software, and the firmware or software may be implemented to include modules, procedures, functions, and the like. The firmware or software configured to perform the descriptions, functions, procedures, suggestions, methods, and / or flowcharts disclosed herein may be included in the one or more processors 102, 202, or may be stored in one or more memories 104, 204 and run by the one or more processors 102, 202. The descriptions, functions, procedures, suggestions, methods and / or flow charts disclosed in this specification may be embodied using firmware or software in the form of code, instructions and / or sets of instructions.

[0220] The one or more memories 104, 204 may be coupled to the one or more processors 102, 202 and may store various forms of data, signals, messages, information, programs, code, instructions, and / or commands. The one or more memories 104, 204 may be comprised of ROM, RAM, EPROM, flash memory, hard drives, registers, cache memory, computer readable storage media, and / or combinations thereof. The one or more memories 104, 204 may be located internal and / or external to the one or more processors 102, 202. Additionally, the one or more memories 104, 204 may be coupled to the one or more processors 102, 202 via various techniques, such as wired or wireless connections.

[0221] One or more transceivers 106, 206 may transmit user data, control information, wireless signals / channels, etc., as described in the methods and / or flow charts, etc., herein to one or more other devices. One or more transceivers 106, 206 may receive user data, control information, wireless signals / channels, etc., as described in the descriptions, functions, procedures, suggestions, methods and / or flow charts, etc., disclosed herein from one or more other devices. For example, one or more transceivers 106, 206 may be coupled to one or more processors 102, 202 and may transmit and receive wireless signals. For example, one or more processors 102, 202 may control one or more transceivers 106, 206 to transmit user data, control information, or wireless signals to one or more other devices. Also, one or more processors 102, 202 may control one or more transceivers 106, 206 to receive user data, control information, or wireless signals from one or more other devices. Furthermore, the one or more transceivers 106, 206 are coupled to one or more antennas 108, 208, and the one or more transceivers 106, 206 are configured to transmit and receive user data, control information, radio signals / channels, etc., as referred to in the descriptions, functions, procedures, suggestions, methods and / or flow charts disclosed herein, via the one or more antennas 108, 208. In this specification, the one or more antennas are multiple physical antennas or multiple logical antennas (e.g., antenna ports). The one or more transceivers 106, 206 convert the received user data, control information, radio signals / channels, etc., from RF band signals to baseband signals for processing using the one or more processors 102, 202. The one or more transceivers 106, 206 convert the user data, control information, radio signals / channels, etc., processed using the one or more processors 102, 202, from baseband signals to RF band signals. For this purpose, the one or more transceivers 106, 206 include (analog) oscillators and / or filters.

[0222] 16 shows another example of a wireless device applicable to the present disclosure. The wireless device may be embodied in various forms depending on the use case / service (see FIG. 14).

[0223] Referring to Fig. 16, the wireless devices 100 and 200 correspond to the wireless devices 100 and 200 of Fig. 15 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 an additional element 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. 15. For example, the transceiver 114 includes one or more transceivers 106 and 206 and / or one or more antennas 108 and 208 in Fig. 15. The control unit 120 is electrically connected to the communication unit 110, the memory unit 130 and the additional element 140 and controls the overall operation of the wireless device. For example, the control unit 120 controls electrical / mechanical operations of the wireless device based on the programs / codes / commands / information stored in the memory unit 130. In addition, the control unit 120 transmits information stored in the memory unit 130 to the outside (e.g., another communication device) via the communication unit 110 through a wireless / wired interface, or stores information received from the outside (e.g., another communication device) via the communication unit 110 through a wireless / wired interface in the memory unit 130.

[0224] The additional element 140 may be configured in various ways depending on the type of wireless device. For example, the additional element 140 may include any one of a power unit / battery, an input / output unit (I / O unit), a driving unit, and a computer unit. The wireless device may be embodied in the form of, but not limited to, a robot (FIG. 14, 100a), a vehicle (FIG. 14, 100b-1, 100b-2), an XR device (FIG. 14, 100c), a mobile device (FIG. 14, 100d), a home appliance (FIG. 14, 100e), an IoT device (FIG. 14, 100f), a digital broadcasting terminal, a hologram device, a public safety device, an MTC device, a medical device, a Fintech device (or a financial device), a security device, a climate / environment device, an AI server / device (FIG. 14, 400), a base station (FIG. 14, 200), and a network node. The wireless device may be mobile or fixed depending on the use case / service.

[0225] In FIG. 16, the various elements, components, units / sections and / or modules within the wireless devices 100, 200 are all coupled to each other by wired interfaces or at least some are wirelessly coupled to each other by a communication unit 110. For example, in the wireless devices 100 and 200, the control unit 120 and the communication unit 110 are connected by wire, and the control unit 120 and a first unit (e.g., 130, 140) are connected wirelessly via the communication unit 110. In addition, each element, component, unit / part and / or module in 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 of a communication control processor, an application processor, an ECU (Electronic control Unit), a graphics processor, a memory control processor, etc. As another example, the memory unit 130 is composed of a Random Access Memory (RAM), a Dynamic RAM (DRAM), a Read Only Memory (ROM), a flash memory, a volatile memory, a non-volatile memory and / or a combination thereof.

[0226] 17 is a diagram illustrating a vehicle or an autonomous vehicle applicable to the present disclosure. The vehicle or the autonomous vehicle may be realized as a mobile robot, a car, a train, an aerial vehicle (AV), a ship, or the like.

[0227] 17, a vehicle or autonomous vehicle 100 includes an antenna unit 108, a communication unit 110, a control unit 120, a drive unit 140a, a power supply unit 140b, a sensor unit 140c, and an autonomous driving unit 140d. The antenna unit 108 is configured as a part of the communication unit 110. Blocks 110 / 130 / 140a to 140d correspond to blocks 110 / 130 / 140 in FIG. 16, respectively.

[0228] The communication unit 110 transmits and receives signals (e.g., data, control signals, etc.) to and from external devices such as other vehicles, base stations (e.g., base stations, road side units, etc.), and servers. The control unit 120 controls elements of the vehicle or autonomous vehicle 100 to perform various operations. The control unit 120 includes an ECU (Electronic Control Unit). The driving unit 140a causes the vehicle or autonomous vehicle 100 to run 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 autonomous vehicle 100 and includes wired / wireless charging circuits, a battery, etc. The sensor unit 140c can obtain vehicle status, 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, a tilt sensor, a weight sensor, a heading sensor, a position module, a vehicle forward / reverse 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 embodies a technology for maintaining a lane while driving, a technology for automatically adjusting speed such as an adaptive cruise control, a technology for automatically driving according to a predetermined route, a technology for automatically setting a route when a destination is set, and the like.

[0229] For 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 (e.g., speed / direction adjustment) so that the vehicle or autonomous driving vehicle 100 moves along the autonomous driving route according to the drive plan. The communication unit 110 non-periodically obtains the latest traffic information data from an external server during autonomous driving, and also obtains surrounding traffic information data from surrounding vehicles. In addition, the sensor unit 140c obtains vehicle status and 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, etc. based on information collected from the vehicle or autonomous driving vehicle, and provide the predicted traffic information data to the vehicle or autonomous driving vehicle.

[0230] FIG. 18 is a diagram for explaining a DRX (Discontinuous Reception) operation of a terminal according to one embodiment of the present invention.

[0231] A terminal can perform DRX operation while executing the procedures and / or methods described / proposed above. A terminal configured for DRX can reduce power consumption by discontinuously receiving DL signals. DRX is performed in RRC (Radio Resource Control)_IDLE state, RRC_INACTIVE state, and RRC_CONNECTED state. DRX in the RRC_IDLE state and RRC_INACTIVE state is used to discontinuously receive paging signals. DRX performed in the RRC_CONNECTED state will be described below (RRC_CONNECTED DRX).

[0232] Referring to FIG. 18, the DRX cycle consists of On Duration and Opportunity for DRX. The DRX cycle defines a time interval in which On Duration is repeated periodically. On Duration indicates a time period in which the terminal monitors to receive the PDCCH. When DRX is configured, the terminal performs PDCCH monitoring during On Duration. If there is a successfully detected PDCCH during PDCCH monitoring, the terminal operates an inactivity timer and maintains an awake state. On the other hand, if there is no successfully detected PDCCH during PDCCH monitoring, the terminal enters a sleep state after the On Duration ends. Thus, when DRX is configured, PDCCH monitoring / reception is performed discontinuously in the time domain when performing the above-described / proposed procedure and / or method. For example, when DRX is configured, in this specification, PDCCH reception opportunities (e.g., slots having a PDCCH search space) are set discontinuously according to the DRX configuration. On the other hand, when DRX is not configured, PDCCH monitoring / reception is performed continuously in the time domain when performing the above / proposed procedures and / or methods. For example, in this specification, PDCCH reception opportunities (e.g., slots having PDCCH search space) are configured continuously when DRX is not configured. On the other hand, PDCCH monitoring may be restricted in the time period configured in the measurement gap regardless of whether DRX is configured or not.

[0233] Table 7 shows the process of the terminal related to DRX (RRC_CONNECTED state). Referring to Table 9, DRX configuration information is received via higher layer (e.g., RRC) signaling, and DRX ON / OFF is controlled by a DRX command of the MAC layer. If DRX is configured, the terminal can perform PDCCH monitoring discontinuously when performing the procedures and / or methods described / proposed in the present invention.

[0234] [Table 7]

[0235] Here, MAC-CellGroupConfig includes configuration information required to set MAC (Medium Access Control) parameters for a cell group. MAC-CellGroupConfig may include configuration information related to DRX. For example, MAC-CellGroupConfig includes the following information in the definition of DRX:

[0236] - Value of drx-OnDurationTimer: defines the length of the start period of the DRX cycle

[0237] - Value of drx-InactivityTimer: defines the length of the time interval in which the UE is in an awake state after a PDCCH opportunity in which a PDCCH indicating initial UL or DL ​​data is detected

[0238] - Value of drx-HARQ-RTT-TimerDL: defines the length of the maximum time interval after a DL initial transmission is received until a DL retransmission is received.

[0239] - Value of drx-HARQ-RTT-TimerDL: defines the length of the maximum time interval between when a grant for a UL initial transmission is received and when a grant for a UL retransmission is received.

[0240] - drx-LongCycleStartOffset: defines the length and start time of a DRX cycle

[0241] - drx-ShortCycle(optional): defines the time length of a short DRX cycle

[0242] Here, if any one of the drx-OnDurationTimer, drx-InactivityTimer, drx-HARQ-RTT-TimerDL, and drx-HARQ-RTT-TimerDL is operating, the terminal maintains an active state and performs PDCCH monitoring at every PDCCH opportunity.

[0243] The above-described embodiments are combinations of the components and features of the present invention in a predetermined form. Each component or feature should be considered as optional unless otherwise expressly stated. Each component or feature may be implemented in a form not combined with other components or features. Also, some components and / or features may be combined to form an embodiment of the present invention. The order of each operation described in the embodiments of the present invention may be changed. Some configurations or features of any embodiment may be included in other embodiments, or may be replaced with corresponding configurations or features of other embodiments. It is obvious that claims that are not explicitly cited in the claims may be combined to form an embodiment, or may be included as a new claim by amendment after filing.

[0244] It is obvious to those skilled in the art that the present invention can be embodied in other specific forms without departing from the characteristics of the present invention. Therefore, the above detailed description should not be interpreted as limiting in all respects, but should be considered as illustrative. The scope of the present invention should be determined by reasonable interpretation of the appended claims, and all modifications within the equivalent scope of the present invention are included in the scope of the present invention. [Industrial Applicability]

[0245] The present invention can be used in a terminal, a base station or other equipment of a wireless mobile communication system.

Claims

1. A method for a terminal (UE) receiving a signal in a wireless communication system, comprising: Monitoring physical downlink control channel (PDCCH) candidates; Detecting downlink control information (DCI) by monitoring the PDCCH candidates; The DCI supports multi-cell scheduling based on a cell combination for a plurality of cells configured in the terminal; A method in which a payload size of the DCI is determined based on a first cell combination among the cell combinations in which a total number of DCI bits required for co-scheduled cells is the largest.

2. The method of claim 1 , wherein the payload of the DCI is determined based on a combined size of all DCI fields for the first cell combination.

3. The method of claim 1 , wherein the co-scheduled cells are indicated in one of the cell combinations by the DCI.

4. The DCI includes, for each of a first cell and a second cell that are co-scheduled, information regarding a first DCI field; 2. The method of claim 1, wherein information regarding a first DCI field for the first cell is positioned prior to information regarding a first DCI field for the second cell within the DCI based on the first cell having a lower serving cell index than the second cell.

5. The first DCI field includes a modulation and coding scheme (MCS) field, a new data indicator (NDI) field, a redundancy version (RV) field, a hybrid automatic repeat request (HARQ) process ID field, a frequency domain resource allocation (FDRA) field, a time domain resource allocation (TDRA) field, and a transmission power (TPC) field for a physical uplink shared channel (PUSCH).

5. The method of claim 4, further comprising at least one of the following fields:

6. The method according to claim 1, wherein a scheduled signal is transmitted or received only to other cells, excluding at least one cell that is not valid, among the cells that are scheduled together by the DCI.

7. 7. The method of claim 6, wherein the at least one cell that is not valid includes at least one of a deactivated secondary cell (SCell), a cell operating as a Dormant bandwidth part (BWP), a cell in which resources of the cell allocated by the DCI overlap with semi-static resources in which UL (uplink) / DL (downlink) directions are set to be different, and a cell in which frequency resource information indicated by the DCI is not valid.

8. The method according to claim 6, wherein the hybrid automatic repeat request-acknowledgement (HARQ-ACK) information is configured for other cells except for the at least one cell that is not valid, or includes negative acknowledgment (NACK) information for the at least one cell that is not valid.

9. The method of claim 6, wherein a DCI field value for the at least one non-valid cell in the DCI is set based on information about a particular bandwidth part (BWP).

10. A computer-readable recording medium having recorded thereon a program for carrying out the method according to claim 1.

11. A device for wireless communication, comprising: A memory for storing instruction words; A processor that operates by executing the instructions; The operations of the processor include: monitoring a physical downlink control channel (PDCCH) candidate; and detecting downlink control information (DCI) by monitoring the PDCCH candidate; The DCI supports multi-cell scheduling based on a cell combination for a plurality of cells configured in the device; The device determines a payload size of the DCI based on a first cell combination among the cell combinations in which a total number of DCI bits required for co-scheduled cells is the largest.

12. a transceiver for transmitting or receiving wireless signals under the control of said processor; The device of claim 11, wherein the device is a terminal (UE) in a wireless communication system.

13. The device according to claim 11, wherein the device is an application specific integrated circuit (ASIC) or a digital signal processing device for controlling a terminal (UE).

14. 1. A method for a base station to transmit a signal in a wireless communication system, comprising: generating downlink control information (DCI); transmitting the DCI to the terminal based on at least one of a physical downlink control channel (PDCCH) candidate of the terminal; The DCI supports multi-cell scheduling based on a cell combination for a plurality of cells configured in the terminal; A method in which a payload size of the DCI is determined based on a first cell combination among the cell combinations in which a total number of DCI bits required for co-scheduled cells is the largest.

15. A base station for transmitting a signal in a wireless communication system, comprising: A transceiver; a processor for generating downlink control information (DCI) and transmitting the DCI by the transceiver to the terminal based on at least one of physical downlink control channel (PDCCH) candidates for the terminal; The DCI supports multi-cell scheduling based on a cell combination for a plurality of cells configured in the terminal; A base station, wherein a payload size of the DCI is determined based on a first cell combination among the cell combinations in which a total number of DCI bits required for co-scheduled cells is maximum.

Images