Method for transmitting HARQ-ACK information, user equipment, processing device, and storage medium, and method for receiving HARQ-ACK information and base station - Patents.com

Abstract

The UE determines a PUCCH cell from among a plurality of cells including a first cell and a second cell different from the first cell based on a first cell slot n on a first cell in which HARQ-ACK transmission for PDSCH reception is scheduled and a predetermined rule for PUCCH cell change, determines a PUCCH cell slot associated with the first cell slot n among slots on the PUCCH cell for the first cell slot n, and determines a target slot in which the HARQ-ACK transmission is postponed based on overlapping of the HARQ-ACK transmission with a downlink symbol in the PUCCH cell slot on the PUCCH cell for the first cell slot n.

Description

[Technical field]

[0001] This specification relates to wireless communication systems. [Background technology]

[0002] Various devices and technologies such as smartphones and tablet PCs (Personal Computers) that require high data transmission volumes, such as machine-to-machine (M2M) communication and machine type communication (MTC), have emerged and become widespread. Accordingly, the volume of data required to be processed by cellular networks is also rapidly increasing. In order to meet the rapidly increasing data processing demands, carrier aggregation technology and cognitive radio technology for efficiently using more frequency bands, multiple antenna technology and multiple base station coordination technology for increasing the data capacity transmitted within limited frequencies, etc. are being developed.

[0003] As many communication devices require larger communication capacity, there is an increasing need for enhanced mobile broadband (eMBB) communication, which is more advanced than legacy radio access technology (RAT).In addition, massive machine type communications (mMTC), which connects multiple devices and objects to provide a variety of services anytime and anywhere, is being considered as the next generation of communication.

[0004] In addition, communication systems designed with services / user equipment (UE) that are sensitive to reliability and latency are also being considered. The introduction of next-generation wireless access technologies is being discussed with eMBB communication, mMTC, Ultra-Reliable and Low Latency Communication (URLLC), etc. Summary of the Invention [Problem to be solved by the invention]

[0005] With the introduction of new wireless communication technologies, not only the number of UEs that a base station should serve in a given resource area is increasing, but also the amount of data and control information that the base station transmits / receives to / from the UEs it serves is increasing. Since the amount of radio resources that a base station can use to communicate with a UE is limited, a new method is required for the base station to efficiently receive / transmit uplink / downlink data and / or uplink / downlink control information from / to the UE using the limited radio resources. In other words, as node density increases and / or UE density increases, a method is required for efficiently utilizing high density nodes or high density user equipment for communication.

[0006] In addition, there is a need for a method for efficiently supporting various services having different requirements in a wireless communication system.

[0007] Additionally, overcoming delay or latency is a significant challenge in the performance of delay or latency sensitive applications.

[0008] It is also desirable to specify how the UE and BS should behave when PUCCH cell change and HARQ deferral are configured.

[0009] The technical objectives to be achieved by the present invention are not limited to those mentioned above, and other technical problems not mentioned may be considered by a person having ordinary skill in the art to which the present invention pertains from the embodiments of the present invention described below. [Means for solving the problem]

[0010] In one aspect of the specification, a method for a user equipment to transmit HARQ-ACK information in a wireless communication system is provided, the method including: performing PDSCH reception; determining a PUCCH cell among a plurality of cells including the first cell and a second cell different from the first cell based on a first cell slot n on a first cell where a HARQ-ACK transmission for the PDSCH reception is scheduled and a predetermined rule for PUCCH cell change; determining a PUCCH cell slot associated with the first cell slot n among slots on the PUCCH cell for the first cell slot n; and determining a target slot to which the HARQ-ACK transmission is postponed based on an overlap of the HARQ-ACK transmission with a downlink symbol in the PUCCH cell slot on the PUCCH cell for the first cell slot n.

[0011] In another aspect of the present invention, a user equipment for transmitting HARQ-ACK information in a wireless communication system is provided. The user equipment includes at least one transceiver, at least one processor, and at least one computer memory operatively connected to the at least one processor and having instructions stored therein that, when executed, cause the at least one processor to perform operations. The operations include performing PDSCH reception, determining a PUCCH cell among a plurality of cells including the first cell and a second cell different from the first cell based on a first cell slot n on a first cell in which a HARQ-ACK transmission for the PDSCH reception is scheduled and a predetermined rule for PUCCH cell change, determining the PUCCH cell slot associated with the first cell slot n among slots on the PUCCH cell for the first cell slot n, and determining a target slot to which the HARQ-ACK transmission is postponed based on an overlap of the HARQ-ACK transmission with a downlink symbol in the PUCCH cell slot on the PUCCH cell for the first cell slot n.

[0012] In yet another aspect of the present specification, a processing device is provided in a wireless communication system, the processing device including at least one processor and at least one computer memory operatively connected to the at least one processor and having instructions stored therein that, when executed, cause the at least one processor to perform operations, the operations including: performing PDSCH reception; determining a PUCCH cell among a plurality of cells including the first cell and a second cell different from the first cell based on a first cell slot n on a first cell in which a HARQ-ACK transmission for the PDSCH reception is scheduled and a predetermined rule for PUCCH cell change; determining a PUCCH cell slot associated with the first cell slot n among slots on the PUCCH cell for the first cell slot n; and determining a target slot to which the HARQ-ACK transmission is postponed based on an overlap of the HARQ-ACK transmission with a downlink symbol in the PUCCH cell slot on the PUCCH cell for the first cell slot n.

[0013] In yet another aspect of the present specification, a computer-readable storage medium is provided, the computer-readable storage medium storing at least one computer program including instructions that, when executed by at least one processor, cause the at least one processor to perform operations for a user equipment, the operations including: performing PDSCH reception; determining a PUCCH cell among a plurality of cells including the first cell and a second cell different from the first cell based on a first cell slot n on a first cell in which a HARQ-ACK transmission for the PDSCH reception is scheduled and a predetermined rule for PUCCH cell change; determining a PUCCH cell slot associated with the first cell slot n among slots on the PUCCH cell for the first cell slot n; and determining a target slot to which the HARQ-ACK transmission is postponed based on an overlap of the HARQ-ACK transmission with a downlink symbol in the PUCCH cell slot on the PUCCH cell for the first cell slot n.

[0014] In yet another aspect of the present specification, a computer program stored on a computer-readable storage medium is provided, the computer program including at least one program code including instructions that, when executed, cause at least one processor to perform operations, the operations including: performing PDSCH reception; determining a PUCCH cell among a plurality of cells including the first cell and a second cell different from the first cell based on a first cell slot n in a first cell in which a HARQ-ACK transmission for the PDSCH reception is scheduled and a predetermined rule for PUCCH cell change; determining a PUCCH cell slot associated with the first cell slot n among slots on the PUCCH cell for the first cell slot n; and determining a target slot to which the HARQ-ACK transmission is postponed based on an overlap of the HARQ-ACK transmission with a downlink symbol in the PUCCH cell slot on the PUCCH cell for the first cell slot n.

[0015] In yet another aspect of the specification, the method includes performing a PDSCH transmission; determining a PUCCH cell among a plurality of cells including the first cell and a second cell different from the first cell based on a first cell slot n on a first cell in which HARQ-ACK reception for the PDSCH transmission is scheduled and a predetermined rule for PUCCH cell change; determining a PUCCH cell slot associated with the first cell slot n among slots on the PUCCH cell for the first cell slot n; and determining a target slot in which the HARQ-ACK reception is postponed based on overlapping of the HARQ-ACK reception with a downlink symbol in the PUCCH cell slot on the PUCCH cell for the first cell slot n.

[0016] In yet another aspect of the present specification, a base station is provided for receiving HARQ-ACK information in a wireless communication system. The base station includes at least one transceiver, at least one processor, and at least one computer memory operatively connected to the at least one processor and having instructions stored therein that, when executed, cause the at least one processor to perform operations. The operations include performing a PDSCH transmission, determining a PUCCH cell among a plurality of cells including the first cell and a second cell different from the first cell based on a first cell slot n on a first cell in which HARQ-ACK reception for the PDSCH transmission is scheduled and a predetermined rule for PUCCH cell change, determining a PUCCH cell slot associated with the first cell slot n among slots on the PUCCH cell for the first cell slot n, and determining a target slot to which the HARQ-ACK reception is postponed based on an overlap of the HARQ-ACK reception with a downlink symbol in the PUCCH cell slot on the PUCCH cell for the first cell slot n.

[0017] In each aspect of this specification, the first cell slot n is a slot in which a HARQ-ACK transmission for the PDSCH is scheduled.

[0018] In each aspect of this specification, the plurality of cells are configured for a PUCCH cell change. Determining the PUCCH cell among the plurality of cells includes determining the PUCCH cell for the first cell slot n among the plurality of cells based on the predetermined rule for the PUCCH cell change.

[0019] In each aspect of this specification, the PUCCH cell slot is the earliest slot in which the HARQ-ACK reception can be performed, determined based on the predetermined rule and the first cell slot on the first cell.

[0020] In each aspect of this specification, HARQ-ACK transmission / reception is performed in the PUCCH cell slot on the PUCCH cell for the first cell slot n based on the fact that the HARQ-ACK transmission does not overlap with downlink symbols in the PUCCH cell slot on the PUCCH cell for the first cell slot n.

[0021] This is the earliest possible slot.

[0022] In each aspect of this specification, determining the target slot includes determining a PUCCH cell for a first cell slot n+k on the first cell based on the predetermined rule, where k is a positive integer, determining a PUCCH cell for a first cell slot n+k+1 on the first cell based on the HARQ-ACK reception overlapping with a downlink symbol in a PUCCH cell slot associated with the first cell slot n+k among slots on the PUCCH cell for the first cell slot n+k, and determining whether the HARQ-ACK transmission / reception is possible in a PUCCH slot on the PUCCH cell for the first cell slot n+k+1 associated with the first cell slot n+k+1.

[0023] In each embodiment of this specification, the PDSCH transmission is a semi-persistently scheduled PDSCH transmission.

[0024] The above-mentioned solutions to problems are merely some of the embodiments of the present invention, and various embodiments reflecting the technical features of the present invention will be derived and understood by those having ordinary skill in the art from the detailed description of the present invention described below. Effect of the Invention

[0025] Some implementations of the present invention allow for efficient transmission and reception of wireless communication signals, thereby increasing the overall throughput of a wireless communication system.

[0026] Some implementations of the present invention can efficiently support a variety of services having different requirements in a wireless communication system.

[0027] Some implementations of the present invention reduce delay / latency experienced during wireless communication between communication devices.

[0028] According to some implementations of the present invention, when the UE can change the cell transmitting the PUCCH for every PUCCH transmission and the UE can postpone the HARQ-ACK transmission of the SPS PDSCH to a later time according to the TDD configuration, a lower latency can be obtained for the HARQ operation by mixing the PUCCH cell change and the HARQ-ACK postponement.

[0029] The effects obtained from 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]

[0030] The drawings attached below are included as part of the detailed description to help understanding of the present invention, illustrate embodiments of the present invention, and together with the detailed description, explain the technical features of the present invention.

[0031] [Figure 1] An example of a communication system 1 to which the present invention can be embodied is shown.

[0032] [Diagram 2] FIG. 2 is a block diagram showing an example of a communication device for carrying out the method according to the present invention;

[0033] [Diagram 3] 1 illustrates another example of a wireless device that may implement an embodiment of the present invention;

[0034] [Figure 4] 1 shows an example of a frame structure that can be used in a wireless communication system based on the 3rd generation partnership project (3GPP (registered trademark)).

[0035] [Diagram 5] 1 shows an example of a resource grid of slots.

[0036] [Figure 6] 1 shows an example of a slot structure used in a 3GPP-based system.

[0037] [Figure 7] 1 shows an example of PDSCH time domain resource allocation by PDCCH and an example of PUSCH time domain resource allocation by PDCCH.

[0038] [Figure 8] 1 shows an example of a hybrid automatic repeat request-acknowledgement (HARQ-ACK) transmission / reception process.

[0039] [Figure 9] 1 shows an example of multiplexing uplink control information (UCI) onto a PUSCH.

[0040] [Figure 10] 1 illustrates an example of a process for a UE with overlapping PUCCH in a single slot to handle collisions between UL channels.

[0041] [Figure 11] FIG. 10 shows an example of a case where UCI is multiplexed.

[0042] [Figure 12] 1 illustrates an example of a process for a UE with overlapping PUCCH and PUSCH in a single slot to handle collisions between UL channels.

[0043] [Figure 13] An example of UCI multiplexing taking into account timeline conditions is shown below.

[0044] [Figure 14] An example of HARQ-ACK deferral is shown.

[0045] [Figure 15] 1 shows an example of PUCCH cell switching.

[0046] [Figure 16] 1 illustrates an example of a HARQ-ACK transmission flow according to some implementations of this specification.

[0047] [Figure 17] 1 illustrates an example of cells and slots in which a HARQ-ACK response may be transmitted according to some implementations of this specification.

[0048] [Figure 18] 1 illustrates an example of a HARQ-ACK receiving flow according to some implementations of this specification. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0049] Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. The detailed description disclosed below together with the accompanying drawings is intended to describe exemplary embodiments of the present invention, and is not intended to show the only embodiment in which the present invention can be implemented. The detailed description below includes specific details to provide a complete understanding of the present invention. However, it is apparent to those skilled in the art that the present invention can be implemented without such specific details.

[0050] In some cases, in order to avoid obscuring the concept of the present invention, known structures and devices are omitted or shown in the form of a block diagram focusing on the core functions of each structure and device. Also, the same components are described throughout this specification with the same reference numerals.

[0051] The techniques, devices, and systems described below can be applied to various wireless multiple access systems. 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, single carrier frequency division multiple access (SC-FDMA) systems, and multi carrier frequency division multiple access (MC-FDMA) systems. CDMA can be implemented by wireless technologies such as Universal Terrestrial Radio Access (UTRA) or CDMA2000. TDMA can be implemented by wireless technologies such as Global System for Mobile communication (GSM), General Packet Radio Service (GPRS), Enhanced Data Rates for GSM Evolution (EDGE) (i.e., GERAN), etc. OFDMA can be implemented by wireless technologies such as IEEE (Institute of Electrical and Electronics Engineers) 802.11 (Wi-Fi), IEEE 802.16 (WiMAX), IEEE 802-20, evolved-UTRA (E-UTRA), etc. UTRA is a part of UMTS (Universal Mobile Telecommunication System), and 3GPP (3rd Generation Partnership Project) LTE (Long Term Evolution) is a part of E-UMTS that uses E-UTRA.3GPP LTE adopts OFDMA for the downlink (DL) and SC-FDMA for the uplink (UL). LTE-advanced (LTE-A) is an evolved form of 3GPP LTE.

[0052] For convenience of explanation, the following description will be made on the assumption that the present invention is applied to a 3GPP-based communication system, for example, LTE or NR. However, the technical features of the present invention are not limited thereto. For example, even if the following detailed description is based on a mobile communication system corresponding to the 3GPP LTE / NR system, the details other than those specific to the 3GPP LTE / NR can be applied to any other mobile communication system.

[0053] For terms and technologies used in this specification that are not specifically explained, please refer to 3GPP-based standard documents, such as 3GPP TS36.211, 3GPP TS36.212, 3GPP TS36.213, 3GPP TS36.321, 3GPP TS36.300, 3GPP TS36.331, 3GPP TS37.213, 3GPP TS38.211, 3GPP TS38.212, 3GPP TS38.213, 3GPP TS38.214, 3GPP TS38.300, 3GPP TS 38.321, 3GPP TS38.331, etc.

[0054] In the embodiments of the present invention described below, the expression that a device "assumes" means that an entity transmitting a channel transmits the channel in accordance with the corresponding "assumption." An entity receiving a channel receives or decodes the channel in a form that conforms to the corresponding "assumption," under the premise that the channel was transmitted in accordance with the corresponding "assumption."

[0055] In the present invention, a UE may be fixed or mobile, and includes various devices that communicate with a base station (BS) to transmit and / or receive user data and / or various control information. The UE is also called a terminal equipment, a mobile station (MS), a mobile terminal (MT), a user terminal (UT), a subscriber station (SS), a wireless device, a personal digital assistant (PDA), a wireless modem, a handheld device, etc. In addition, in the present invention, a BS generally refers to a fixed station that communicates with a UE and / or other BSs, and communicates with the UE and other BSs to exchange various data and control information. The BS is also called other terms such as an advanced base station (ABS), a node-B (NB), an evolved-nodeB (eNB), a base transceiver system (BTS), an access point (Access Point), a processing server (PS), etc. In particular, a UTRAN base station is called a Node-B, an E-UTRAN base station is called an eNB, and a new radio access technology network base station is called a gNB. Hereinafter, for convenience of explanation, base stations will be collectively referred to as BS regardless of the type or version of communication technology.

[0056] In the present invention, a node refers to a fixed point that can communicate with a UE and transmit / receive a radio signal. Various types of BSs can be used as nodes regardless of their names. For example, a BS, an NB, an eNB, a pico cell eNB (PeNB), a home eNB (HeNB), a relay, a repeater, etc. can be used as a node. Also, a node does not have to be a BS. For example, a radio remote head (RRH) or a radio remote unit (RRU) can be used. RRHs, RRUs, etc. generally have a power level lower than that of a BS. RRHs or RRUs (hereinafter, RRHs / RRUs) are generally connected to a BS via a dedicated line such as an optical cable, and therefore generally, cooperative communication between an RRH / RRU and a BS can be performed more smoothly than cooperative communication between a BS connected via a wireless line. At least one antenna is installed in one node. This antenna can refer to a physical antenna, an antenna port, a virtual antenna, or an antenna group. A node is also called a point.

[0057] In the present invention, a cell refers to a certain geographical area where one or more nodes provide communication services. Therefore, in the present invention, communicating with a specific cell means communicating with a BS or a node providing communication services to the specific cell. Also, a downlink / uplink signal of a specific cell means a downlink / uplink signal from / to a BS or a node providing communication services to the specific cell. A cell providing uplink / downlink communication services to a UE is particularly called a serving cell. Also, a channel state / quality of a specific cell means a channel state / quality of a channel or communication link formed between a BS or a node providing communication services to the specific cell and a UE. In a 3GPP-based communication system, a UE can measure a downlink channel state from a specific node using a Cell-specific Reference Signal (CRS) transmitted on a CRS resource allocated to the specific node by an antenna port of the specific node and / or a Channel State Information Reference Signal (CSI-RS) transmitted on a CSI-RS resource.

[0058] Meanwhile, the 3GPP-based communication system uses the concept of a cell to manage radio resources, but a cell associated with a radio resource is distinct from a cell of a geographical area.

[0059] A "cell" of a geographical area can be understood as the coverage where a node can provide a service using a carrier, and a "cell" of radio resources relates to a bandwidth (BW), which is a frequency range configured by said carrier. Since downlink coverage, the range where a node can transmit a valid signal, and uplink coverage, the range where a valid signal can be received from a UE, depend on the carrier carrying the signal, the coverage of a node can also be related to the coverage of a "cell" of radio resources used by said node. Thus, the term "cell" can sometimes be used to refer to the coverage of a service by a node, sometimes to a radio resource, and sometimes to the range where a signal using said radio resource can reach with effective strength.

[0060] Meanwhile, 3GPP communication standards use the concept of a cell to manage radio resources. A "cell" in relation to radio resources is defined as a combination of downlink resources (DL resources) and uplink resources (UL resources), i.e., a combination of a DL component carrier (CC) and a UL CC. A cell can be configured with DL resources alone or a combination of DL resources and UL resources. If carrier aggregation is supported, the linkage between the carrier frequency of the DL resources (or DL ​​CC) and the carrier frequency of the UL resources (or UL CC) can be indicated by system information. For example, the combination of DL resources and UL resources is indicated by System Information Block Type 2 (SIB2) linkage. Here, the carrier frequency is the same as or different from the center frequency of each cell or CC. When carrier aggregation (CA) is configured, the UE has only one radio resource control (RRC) connection with the network. One serving cell provides non-access stratum (NAS) mobility information during RRC connection establishment / re-establishment / handover, and one serving cell provides security input during RRC connection re-establishment / handover. Such a cell is called a primary cell (Pcell). A Pcell is a cell that operates on a primary frequency where a UE performs an initial connection establishment procedure or initiates a connection re-establishment procedure, and a secondary cell (Scell) can be configured according to the UE capabilities to form a set of serving cells together with the Pcell.An Scell ​​can be set up after RRC (Radio Resource Control) connection establishment, and is a cell that provides additional radio resources in addition to the resources of a special cell (SPcell). In the downlink, a carrier corresponding to a Pcell is called a Downlink Primary CC (DL PCC), and in the uplink, a carrier corresponding to a Pcell is called a UL Primary CC (DL PCC). In the downlink, a carrier corresponding to an Scell ​​is called a DL Secondary CC (DL SCC), and in the uplink, a carrier corresponding to an Scell ​​is called a UL Secondary CC (UL SCC).

[0061] In case of dual connectivity (DC) operation, the term special cell (SpCell) refers to a Pcell in a master cell group (MCG) or a primary secondary cell (PSCell) in a secondary cell group (SCG). An SpCell supports PUCCH transmission and contention-based optional access and is always activated. An MCG is a group of serving cells associated with a master node (e.g., BS) and consists of an SpCell (Pcell) and optionally one or more Scells. For a UE configured in DC, an SCG is a subset of serving cells associated with a secondary node and consists of a primary secondary cell (PSCell) and zero or more Scells. A PSCell is the primary Scell ​​of an SCG. For a UE in RRC_CONNECTED state not configured in CA or DC, there is only one serving cell consisting of only a Pcell. For a UE in RRC_CONNECTED state configured in CA or DC, the term serving cell refers to the set of cells consisting of SpCell and all Scells. In DC, two medium access control (MAC) entities are configured in the UE: one for the MCG and one for the SCG.

[0062] For a UE configured with CA but not configured with DC, a Pcell PUCCH group (also referred to as a primary PUCCH group) consisting of a Pcell and zero or more Scells and an Scell ​​PUCCH group (also referred to as a secondary PUCCH group) consisting of only Scells are configured. For an Scell, an Scell ​​(hereinafter, PUCCH cell) is configured to transmit a PUCCH associated with the cell. An Scell ​​designated as a PUCCH Scell ​​belongs to an Scell ​​PUCCH group (i.e., a secondary PUCCH group), and PUCCH transmission of associated UCI is performed on the PUCCH Scell, and an Scell ​​designated as a PUCCH transmission cell is not designated as a PUCCH Scell ​​or a cell designated as a PUCCH transmission cell belongs to a Pcell PUCCH group (i.e., a primary PUCCH group), and PUCCH transmission of associated UCI is performed on the Pcell. Hereinafter, when a UE is configured with an SCG and some embodiments of the present invention related to a PUCCH are applied to the SCG, a primary cell refers to a PSCell of the SCG. When a UE is configured with a PUCCH Scell ​​and some embodiments of the present invention related to PUCCH are applied to a secondary PUCCH group, a primary cell refers to the PUCCH Scell ​​of the secondary PUCCH group.

[0063] In a wireless communication system, a UE receives information from a BS via a downlink (DL), and transmits information to a BS via an uplink (UL). The information transmitted and / or received by the BS and the UE includes data and various control information, and various physical channels exist depending on the type / purpose of the information transmitted and / or received.

[0064] The 3GPP-based communication standard defines downlink physical channels corresponding to resource elements carrying information originating from a higher layer, and downlink physical signals corresponding to resource elements used by the physical layer but not carrying information originating from a higher layer. For example, a physical downlink shared channel (PDSCH), a physical broadcast channel (PBCH), a physical downlink control channel (PDCCH), etc. are defined as downlink physical channels, and a reference signal and a synchronization signal (SS) are defined as downlink physical signals. A reference signal (RS), also called a pilot, refers to a signal with a predefined special waveform that is known to the BS and the UE, and for example, a demodulation reference signal (DMRS) and a channel state information RS (CSI-RS) are defined as downlink reference signals. The 3GPP infrastructure communication standard defines uplink physical channels corresponding to resource elements carrying information originating from a higher layer, and uplink physical signals corresponding to resource elements used by the physical layer but not carrying information originating from a higher layer. For example, a physical uplink shared channel (PUSCH), a physical uplink control channel (PUCCH), and a physical random access channel (PRACH) are defined as uplink physical channels, and a demodulation reference signal (DMRS) for uplink control / data signals, a sounding reference signal (SRS) used for uplink channel measurement, etc. are defined.

[0065] In this specification, PDCCH (Physical Downlink Control CHannel) refers to a set of time-frequency resources (e.g., resource elements (RE)) carrying DCI (downlink control information), and PDSCH (Physical Downlink Shared CHannel) refers to a set of time-frequency resources carrying downlink data. PUCCH (Physical Uplink Control CHannel), PUSCH (Physical Uplink Shared CHannel), and PRACH (Physical Random Access CHannel) respectively refer to sets of time-frequency resources carrying UCI (Uplink Control Information), uplink data, and optional access signals. Hereinafter, the expression that a user equipment transmits / receives PUCCH / PUSCH / PRACH is used to mean the same as transmitting / receiving uplink control information / uplink data / optional access signals on or through PUCCH / PUSCH / PRACH, respectively. In addition, the term "BS transmits / receives the PBCH / PDCCH / PDSCH" is used interchangeably to mean transmitting broadcast information / downlink control information / downlink data on or through the PBCH / PDCCH / PDSCH, respectively.

[0066] In this specification, the radio resources (eg, time-frequency resources) scheduled or configured by the BS to the UE for transmitting or receiving the PUCCH / PUSCH / PDSCH are also referred to as PUCCH / PUSCH / PDSCH resources.

[0067] Since the communication device receives the synchronization signal block (SSB), DMRS, CSI-RS, PBCH, PDCCH, PDSCH, PUSCH, and / or PUCCH in the form of a radio signal in a cell, it cannot select only a radio signal including a specific physical channel or a specific physical signal and receive it in an RF receiver, or select only a radio signal excluding a specific physical channel or physical signal and receive it in an RF receiver. In actual operation, the communication device receives a radio signal in a cell using an RF receiver, converts the radio signal, which is an RF band signal, to a baseband signal, and decodes the physical signal and / or physical channel in the baseband signal using one or more processors. Therefore, in some implementations of this specification, receiving a physical signal and / or a physical channel does not actually mean that the communication device never receives a radio signal including the corresponding physical signal and / or physical channel, but does not attempt to recover the physical signal and / or physical channel from the radio signal, for example, does not attempt to decode the physical signal and / or physical channel.

[0068] As more communication devices require larger communication capacity, there is an increasing need for improved mobile broadband communication compared to existing radio access technology (RAT). In addition, massive machine type communications (mMTC), which connects a large number of devices and objects to provide various services anytime and anywhere, is one of the main issues in next-generation communications. In addition, communication system designs that take into account reliability and latency-sensitive services / UEs are also being considered. Thus, the introduction of next-generation RATs that take into account advanced mobile broadband communications, mMTC, URLLC (Ultra-Reliable and Low Latency Communication), etc. is being discussed. Currently, 3GPP is conducting research on next-generation mobile communication systems after EPC. For convenience, in this invention, the relevant technology is referred to as new RAT (NR) or 5G RAT, and a system that uses or supports NR is referred to as an NR system.

[0069] FIG. 1 shows an example of a communication system 1 to which the present invention is applied. Referring to FIG. 1, the communication system 1 to which the present invention is applied includes a wireless device, a BS, and a network. Here, the wireless device means a device that communicates using a wireless connection technology (e.g., 5G NR, LTE (e.g., E-UTRA)), and is also referred to as a communication / wireless / 5G device. The wireless device includes, but is not limited to, a robot 100a, a vehicle 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 Things) device 100f, and an AI device / server 400. For example, the vehicle includes a vehicle equipped with a wireless communication function, an autonomous vehicle, a vehicle capable of inter-vehicle communication, and the like. Here, the vehicle includes a UAV (Unmanned Aerial Vehicle) (e.g., a drone). XR devices include AR (Augmented Reality), VR (Virtual Reality), and MR (Mixed Reality) devices, and are embodied in the form of HMDs (Head-Mounted Devices), HUDs (Head-Up Displays) mounted on vehicles, TVs, smartphones, computers, wearable devices, home appliances, digital billboards, vehicles, robots, etc. Mobile 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, BSs and networks can also be embodied as wireless devices, and a specific wireless device can operate as a BS / network node for other wireless devices.

[0070] The wireless devices 100a to 100f are connected to a network 300 via a BS 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 BS 200 / network 300, but can also communicate directly without going through the BS / 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.

[0071] Wireless communication / connections 150a, 150b are performed between the wireless devices 100a-100f / BS 200-BS 200 / wireless devices 100a-100f. 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) (e.g., 5G NR). Through the wireless communication / connections 150a, 150b, the wireless devices and the BS / wireless devices can transmit / receive wireless signals to each other. For example, according to 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.

[0072] Fig. 2 is a block diagram showing an example of a communication device that performs a method according to the present invention. Referring to Fig. 2, a first wireless device 100 and a second wireless device 200 transmit and / or receive wireless signals according to various wireless access technologies (e.g., LTE, NR). Here, {first wireless device 100, second wireless device 200} corresponds to {wireless device 100x, BS 200} and / or {wireless device 100x, wireless device 100x} in Fig. 1.

[0073] 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 functions, procedures and / or methods described / suggested below. 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 procedures and / or methods described / suggested below. 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 the present invention, a wireless device may also refer to a communication modem / circuit / chip.

[0074] 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 functions, procedures and / or methods described / suggested below. 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 procedures and / or methods described / suggested below. 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 the present invention, a wireless device may also refer to a communication modem / circuit / chip.

[0075] The wireless communication technology implemented in the wireless devices 100 and 200 of this specification includes not only LTE, NR, and 6G, but also NB-IoT (Narrowband Internet of Things) for low power communication. At this time, for example, the NB-IoT technology is an example of LPWAN (Low Power Wide Area Network) technology and may be implemented in a standard such as LTE Cat NB1 and / or LTE Cat NB2, and is not limited to the above-mentioned names. Additionally or alternatively, the wireless communication technology implemented in the wireless devices XXX and YYY of this specification communicates based on the LTE-M technology. At this time, as an example, the LTE-M technology is an example of LPWAN technology and may be called various names such as eMTC (enhanced Machine Type Communication). For example, the LTE-M technology may be implemented in any one of various standards such as 1) LTE CAT0, 2) LTE Cat M1, 3) LTE Cat M2, 4) LTE non-BL (non-Bandwidth Limited), 5) LTE-MTC, 6) LTE Machine Type Communication, and / or 7) LTE M, and is not limited to the above-mentioned names. Additionally or alternatively, the wireless communication technology embodied in the wireless device XXX, YYY of this specification may include any of ZigBee, Bluetooth, and Low Power Wide Area Network (LPWAN) considering low power communication, but is not limited to the above names. As an example, ZigBee technology creates personal area networks (PANs) related to small / low power digital communication based on various standards such as IEEE802.15.4, and is called by various names.

[0076] The hardware elements of the wireless devices 100, 200 are described in more detail below. One or more protocol layers may be implemented by, but are not limited to, one or more processors 102, 202. For example, the one or more processors 102, 202 may implement one or more layers (e.g., functional layers such as a physical (PHY) layer, a medium access control (MAC) layer, a radio link control (RLC) layer, a packet data convergence protocol (PDCP) layer, a radio resource control (RRC) layer, and a service data adaptation protocol (SDAP) layer). 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 functions, procedures, suggestions, and / or methods disclosed herein. The one or more processors 102, 202 generate messages, control information, data or information according to the functions, procedures, suggestions and / or methods disclosed herein. The one or more processors 102, 202 generate 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 provide to the one or more transceivers 106, 206. The one or more processors 102, 202 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 functions, procedures, suggestions and / or methods disclosed herein.

[0077] 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 functions, procedures, suggestions, and / or methods 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 functions, procedures, suggestions, and / or methods 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 functions, procedures, suggestions and / or methods disclosed in this specification may be embodied using firmware or software in the form of code, instructions and / or sets of instructions.

[0078] The one or more memories 104, 204 are coupled to the one or more processors 102, 202 and store various types 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.

[0079] The one or more transceivers 106, 206 transmit user data, control information, wireless signals / channels, etc., as described in the methods and / or flowcharts, etc., described herein to one or more other devices. The one or more transceivers 106, 206 receive user data, control information, wireless signals / channels, etc., as described in the functions, procedures, suggestions, methods and / or flowcharts, etc., described herein from one or more other devices. For example, the one or more transceivers 106, 206 are coupled to one or more processors 102, 202 to transmit and receive wireless signals. For example, the one or more processors 102, 202 control the one or more transceivers 106, 206 to transmit user data, control information, or wireless signals to one or more other devices. Also, the one or more processors 102, 202 control the one or more transceivers 106, 206 to receive user data, control information, or wireless signals from one or more other devices. Also, 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, wireless signals / channels, etc., as described, 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 may be 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, wireless 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, wireless signals / channels, etc., processed using the one or more processors 102, 202, from baseband signals to RF band signals. For this purpose, one or more of the transceivers 106, 206 include (analog) oscillators and / or filters.

[0080] FIG. 3 shows another example of a wireless device for implementing the present invention. Referring to FIG. 3, the wireless device 100, 200 corresponds to the wireless device 100, 200 of FIG. 2 and is composed of various elements, components, units / parts and / or modules. For example, the wireless device 100, 200 includes 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, 202 and / or one or more memories 104, 204 in FIG. 2. For example, the transceiver 114 includes one or more transceivers 106, 206 and / or one or more antennas 108, 208 in FIG. 2. 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 an external device (e.g., another communication device) via the communication unit 110 through a wireless / wired interface, or stores information received from an external device (e.g., another communication device) via the communication unit 110 through a wireless / wired interface in the memory unit 130.

[0081] 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. 1, 100a), a vehicle (FIG. 1, 100b-1, 100b-2), an XR device (FIG. 1, 100c), a mobile device (FIG. 1, 100d), a home appliance (FIG. 1, 100e), an IoT device (FIG. 1, 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. 1, 400), a BS (FIG. 1, 200), and a network node. The wireless device may be mobile or fixed depending on the use case / service.

[0082] In Fig. 3, various elements, components, units / parts and / or modules in the wireless devices 100 and 200 are connected to each other by a wired interface as a whole, or at least some of them are connected wirelessly by the 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 by the communication unit 110. 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 configured with one or more processor sets. For example, the control unit 120 is configured with 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 may be 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.

[0083] In the present invention, at least one memory (e.g., 104 or 204) stores instructions or programs that, when executed, cause at least one processor operably coupled to the at least one memory to perform operations according to some embodiment or implementation of the present invention.

[0084] In the present invention, a computer-readable (non-volatile) storage medium stores at least one instruction or computer program, which, when executed by at least one processor, can cause the at least one processor to perform operations according to some embodiments or implementations of the present invention.

[0085] In the present invention, a processing device or apparatus includes at least one processor and at least one computer memory coupled to the at least one processor, the at least one computer memory storing instructions or programs that, when executed, cause the at least one processor operably coupled to the at least one memory to perform operations according to some embodiments or implementations of the present invention.

[0086] In the present invention, a computer program is stored in at least one computer-readable (non-volatile) storage medium and includes program code that, when executed, performs operations according to some embodiments of the present invention or causes at least one processor to perform operations according to some embodiments of the present invention. The computer program is provided in the form of a computer program product. The computer program product includes at least one computer-readable (non-volatile) storage medium.

[0087] A communications device of the present invention includes at least one processor and at least one computer memory operably coupled to the at least one processor and storing instructions that, when executed, cause the at least one processor to perform operations in accordance with examples of the present invention as described below.

[0088] FIG. 4 is a diagram showing an example of a frame structure that can be used in a 3GPP-based wireless communication system.

[0089] The frame structure of FIG. 4 is merely an example, and the number of subframes, slots, and symbols in a frame can be changed in various ways. In an NR system, OFDM numerology (e.g., subcarrier spacing (SCS)) is set to be different between multiple cells aggregated to one UE. Thus, the (absolute time) duration of a time resource (e.g., subframe, slot, or transmission time interval (TTI)) consisting of the same number of symbols is set to be different between the aggregated cells. Here, the symbols include OFDM symbols (or cyclic prefix-orthogonal frequency division multiplexing (CP-OFDM) symbols) and SC-FDMA symbols (or discrete Fourier transform-spread-OFDM (DFT-s-OFDM) symbols). In this specification, the terms symbol, OFDM-based symbol, OFDM symbol, CP-OFDM symbol and DFT-s-OFDM symbol are interchangeable.

[0090] Referring to FIG. 4, in an NR system, uplink and downlink transmissions are organized into frames. Each frame is T f =(△f max *N f / 100)*T c = 10 ms duration, divided into two half frames of 5 ms duration each. Here, the basic time unit for NR is T c =1 / (△f max *N f ) and △f max =480*10 3 Hz and N f = 4096. For reference, the basic time unit for LTE is T s =1 / (△f ref *N f,ref) and △f ref =15*10 3 Hz and N f,ref = 2048. c and T f is the constant κ=T c / T f Each half frame is composed of five subframes, and the duration of a single subframe is T sf is 1 ms. The subframe is divided into slots, and the number of slots in a subframe depends on the subcarrier spacing. Each slot consists of 14 or 12 OFDM symbols based on the cyclic prefix. In normal cyclic prefix (CP), each slot consists of 14 OFDM symbols, and in extended CP, each slot consists of 12 OFDM symbols. The pneumatology supports an exponentially scalable subcarrier spacing △f=2 u *Depends on 15kHz. The following table shows the subcarrier spacing for general CP: △f=2 u *Number of OFDM symbols per slot at 15 kHz (N slot symb ), the number of slots per frame (N frame,u slot ) and the number of slots per subframe (N subframe,u slot ) is shown.

[0091] [Table 1]

[0092] The following table shows the subcarrier spacing for extended CP, △f=2 u *Indicates the number of OFDM symbols per slot, the number of slots per frame, and the number of slots per subframe at 15 kHz.

[0093] [Table 2]

[0094] For a subcarrier spacing setting u, the slots are assigned n u s ∈{0,…,n subframe,u slot -1}, and in increasing order within a frame, n u s,f ∈{0,…,n frame,u slot -1}.

[0095] FIG. 5 shows an example of a resource grid of a slot. A slot includes multiple (e.g., 14 or 12) symbols in the time domain. For each neurology (e.g., subcarrier spacing) and carrier, N common resource blocks (CRBs) are allocated as indicated by higher layer signaling (e.g., radio resource control (RRC) signaling). start,u grid Starts with N size,u grid,x *N RB sc subcarriers and N subframe,u symb A resource grid of N OFDM symbols is defined, where size,u grid,x is the number of resource blocks (RB) in the source grid, and the subscript x is DL for downlink and UL for uplink. RB sc is the number of subcarriers per RB, and in the 3GPP-based wireless communication system, N RB sc is typically 12. For a given antenna port p, subcarrier spacing configuration u and transmission direction (DL or UL), there is one resource grid. size,u gridis given to the UE by higher layer parameters from the network (e.g., RRC parameters). Each element in the resource grid for antenna port p and subcarrier spacing setting u is called a resource element (RE), and one complex symbol is mapped to each resource element. Each resource element in the resource grid is uniquely identified by index k in the frequency domain and index l indicating the symbol position relative to a reference point in the time domain. In NR systems, RBs are defined by 12 consecutive subcarriers in the frequency domain. In NR systems, RBs are classified into common resource blocks (CRBs) and physical resource blocks (PRBs). CRBs are numbered from 0 upwards in the frequency domain for subcarrier spacing setting u. The center of subcarrier 0 of CRB0 for subcarrier spacing setting u coincides with 'point A', which is the common reference point for the resource block grid. PRBs for subcarrier spacing setting u are defined in bandwidth parts (BWPs) and range from 0 to N size,u BWP,i The common resource block n is numbered from i to -1, where i is the number of the bandwidth part. u CRB and physical resource block n in bandwidth part i PRB The relationship between is as follows: u PRB =n u CRB +N start,u BWP,i , where N start,u BWP,i is the common resource block whose bandwidth part starts relative to CRB0. A BWP includes multiple consecutive RBs in the frequency domain. For example, a BWP is a given neurology U within BWPi on a given carrier. iA CRB is a subset of contiguous CRBs defined for a carrier. A carrier contains up to N BWPs (e.g., 5). A UE is configured to have one or more BWPs on a given component carrier. Data communication is performed by the activated BWPs, and only a predetermined number (e.g., one) of the BWPs configured in the UE are activated on the corresponding carrier.

[0096] For each serving cell in the set of DL BWPs or UL BWPs, the network configures at least an initial DL BWP and one (if the serving cell is configured with an uplink) or two initial UL BWPs (if a supplementary uplink is used). The network may also configure additional UL and DL BWPs for the serving cell. For each DL BWP or UL BWP, the UE is provided with the following parameters for the serving cell: i) subcarrier spacing, ii) cyclic prefix, iii) N start BWP = 275, offset RB set and length L RB The RRC parameter locationAndBandwidth indicates the CRB N as a resource indicator value (RIV). start BWP =O carrier +RB start and the number of contiguous RBs, N size BWP =L RB , and the subcarrier spacing is given by the RRC parameter offsetToCarrier carrier ; Index within the set of DL BWP or UL BWP; set of BWP-common parameters and set of BWP-specific parameters.

[0097] Virtual resource blocks (VRBs) are defined within the bandwidth part and range from 0 to N size,u BWP,iNumbered from -1, where i is the bandwidth part number. VRBs are mapped to physical resource blocks (PRBs) by non-interleaved mapping. In some implementations, in the case of non-interleaved VRB-to-PRB mapping, VRB n is mapped to PRB n.

[0098] A UE configured with carrier aggregation is configured to use one or more cells. If a UE is configured with multiple serving cells, the UE is configured with one or more cell groups. The UE is configured with multiple cell groups associated with different BSs. Alternatively, the UE is configured with multiple cell groups associated with a single BS. Each cell group of the UE is composed of one or more serving cells, and each cell group includes a single PUCCH cell with PUCCH resources configured. A PUCCH cell is a Pcell or an Scell ​​of a corresponding cell group that is configured as a PUCCH cell. Each serving cell of the UE belongs to one of the UE's cell groups, and does not belong to multiple cell groups.

[0099] FIG. 6 illustrates an example of a slot structure that can be used in a 3GPP-based system. In all 3GPP-based systems, e.g., NR systems, each slot has a self-contained structure that includes i) DL control channel, ii) DL or UL data, and / or iii) UL control channel. For example, the first N symbols in a slot are used to transmit DL control channel (hereinafter, DL control region), and the last M symbols in a slot are used to transmit UL control channel (hereinafter, UL control region). N and M are each a non-negative integer. A resource region between the DL control region and the UL control region (hereinafter, data region) is used for DL ​​data transmission or UL data transmission. Symbols in a single slot are divided into DL, UL, or a group of consecutive symbols that can be flexibly used. Hereinafter, information indicating how the symbols in each slot are used is referred to as a slot format. For example, the slot format can define which symbols in a slot are used for UL and which symbols are used for DL.

[0100] If the serving cell is to operate in time division duplex (TDD) mode, the BS can configure the pattern for UL and DL allocation for the serving cell via higher layer (e.g., RRC) signaling. For example, the following parameters are used to configure the TDD DL-UL pattern:

[0101] - dL-UL-TransmissionPeriodicity, which provides the periodicity of the DL-UL pattern;

[0102] - nrofDownlinkSlots giving the number of first consecutive full DL slots of each DL-UL pattern, where a full DL slot is a slot that contains only downlink symbols;

[0103] - nrofDownlinkSymbols, giving the number of consecutive DL symbols at the beginning of the slot immediately following the last full DL slot;

[0104] nrofUplinkSlots, giving the number of consecutive full UL slots within the end of each DL-UL pattern, where a full UL slot is a slot that has only uplink symbols; and

[0105] - nrofUplinkSymbols gives the number of consecutive UL symbols in the end of the slot immediately preceding the first complete UL slot.

[0106] Among the symbols in the DL-UL pattern, the remaining symbols that are not set as DL symbols or UL symbols are flexible symbols.

[0107] A UE that has received a configuration for a TDD DL-UL pattern, i.e., a TDD UL-DL configuration (e.g., tdd-UL-DL-ConfigurationCommon or tdd-UL-DLConfigurationDedicated) via higher layer signaling, sets the slot format per slot across slots based on this configuration.

[0108] Although various combinations of DL symbols, UL symbols, and flexible symbols are possible for symbols, a certain number of combinations can be predefined as slot formats, and the predefined slot formats are identified by slot format indexes. The following table shows some examples of predefined slot formats. In the following table, D stands for DL ​​symbol, U stands for UL symbol, and F stands for flexible symbol.

[0109] [Table 3]

[0110] In order to inform the UE which of the predetermined slot formats is used in a particular slot, the BS may configure a set of slot format combinations applicable to the corresponding serving cell for each cell by higher layer (e.g., RRC) signaling for a set of serving cells, and may configure the UE to monitor a group-common PDCCH for a slot format indicator (SFI) by higher layer (e.g., RRC) signaling. Hereinafter, the DCI carried by the group-common PDCCH for SFI is referred to as SFI DCI. DCI format 2_0 is used as SFI DCI. For example, for each serving cell in the set of serving cells, the BS may provide the UE with the (start) position of the slot format combination ID (i.e., SFI-index) for the corresponding serving cell in the SFI DCI, the set of slot format combinations applicable to the corresponding serving cell, the setting of reference subcarrier spacing for each slot format in the slot format combination indicated by the SFI-index value in the SFI DCI, and the like. For each slot format combination in the set of slot format combinations, one or more slot formats are configured and a slot format combination ID (i.e., SFI-index) is assigned. For example, if the BS wants to configure a slot format combination with N slot formats, it can indicate N slot format indexes among the slot format indexes for a given slot format (e.g., see Table 3) for the corresponding slot format combination. The BS informs the UE of the SFI-RNTI, which is a Radio Network Temporary Identifier (RNTI) used for the SFI, and the total length of the DCI payload to be scrambled into the SFI-RNTI, in order to configure the UE to monitor the group-common PDCCH for the SFI.When the UE detects the PDCCH based on the SFI-RNTI, the UE can determine the slot format for the serving cell from the SFI-index for the serving cell among the SFI-indexes in the DCI payload in the PDCCH.

[0111] A symbol designated as flexible by the TDD DL-UL pattern configuration can be designated as uplink, downlink or flexible by the SFI DCI. A symbol designated as downlink / uplink by the TDD DL-UL pattern configuration cannot be overridden as uplink / downlink or flexible by the SFI DCI.

[0112] If a TDD DL-UL pattern is not configured, the UE determines whether each slot is uplink or downlink and the symbol allocation within each slot based on the SFI DCI and / or a DCI that schedules or triggers the transmission of a downlink or uplink signal (e.g., DCI format 1_0, DCI format 1_1, DCI format 1_2, DCI format 0_0, DCI format 0_1, DCI format 0_2, DCI format 2_3).

[0113] The NR frequency band is defined by two types of frequency ranges, FR1 and FR2, also known as millimeter wave (mmW). The table below illustrates the frequency ranges in which NR can operate:

[0114] [Table 4]

[0115] The physical channels used in 3GPP-based wireless communication systems will now be described in more detail.

[0116] The PDCCH carries DCI. For example, the PDCCH (i.e., DCI) carries the transmission format and resource allocation of a downlink shared channel (DL-SCH), resource allocation information for an uplink shared channel (UL-SCH), paging information for a paging channel (PCH), system information on a DL-SCH, resource allocation information for a control message of a layer (hereinafter, a higher layer) located above the physical layer in the protocol stack of a UE / BS, such as a random access response (RAR) transmitted on a PDSCH, a transmission power control command, activation / cancellation of configured scheduling (CS), etc. DCI including resource allocation information for DL-SCH is called PDSCH scheduling DCI, and DCI including resource allocation information for UL-SCH is called PUSCH scheduling DCI. The DCI includes a cyclic redundancy check (CRC), which 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 UE, the CRC is masked to a UE identifier (e.g., cell RNTI (C-RNTI)). If the PDCCH is for paging, the CRC is masked to a paging RNTI (P-RNTI). If the PDCCH is for system information (e.g., system information block (SIB)), the CRC is masked to a system information RNTI (SI-RNTI). If the PDCCH is for an unsolicited access response, the CRC is masked to a random access RNTI (RA-RATI).

[0117] The PDCCH on one serving cell scheduling the PDSCH or PUSCH of another serving cell is called cross-carrier scheduling. Cross-carrier scheduling using a carrier indicator field (CIF) can allow the PDCCH of a serving cell to schedule resources on another serving cell. Meanwhile, the PDSCH on a serving cell scheduling the PDSCH or PUSCH to the serving cell is called self-carrier scheduling. If cross-carrier scheduling is used in a cell, the BS provides the UE with information about the cell that schedules this cell. For example, the BS provides the UE with information about whether the serving cell is scheduled by the PDCCH on the other (scheduling) cell or scheduled by the serving cell, and which cell signals the downlink assignment and uplink grant for the serving cell if the serving cell is scheduled by the other (scheduling) cell. In this specification, a cell that carries a PDCCH is referred to as a scheduling cell, and a cell in which transmission of a PUSCH or PDSCH is scheduled by DCI included in the PDCCH, i.e., a cell that carries a PUSCH or PDSCH scheduled by the PDCCH, is referred to as a scheduled cell.

[0118] PDSCH is a physical layer UL channel for UL data transport. PDSCH carries downlink data (e.g. DL-SCH transport block) and uses modulation methods such as QPSK (Quadrature Phase Shift Keying), 16QAM (Quadrature Amplitude Modulation), 64QAM, and 256QAM. A transport block (TB) is encoded to generate a codeword. PDSCH can carry up to two codewords. Scrambling and modulation mapping are performed for each codeword, and modulation symbols generated from each codeword are mapped to one or more layers. Each layer is mapped to radio resources together with DMRS, generated into an OFDM symbol signal, and transmitted through the corresponding antenna port.

[0119] PUCCH means a physical layer UL channel for UCI transmission. PUCCH carries UCI (Uplink Control Information). UCI types transmitted on PUCCH include hybrid automatic repeat request (HARQ)-acknowledgement (ACK) information, scheduling request (SR) and channel state information (CSI). UCI bits include HARQ-ACK information bits if available, SR information bits if available, LRR information bits if available, and CSI bits if available. In this specification, HARQ-ACK information bits correspond to HARQ-ACK codebook. In particular, a bit sequence in which HARQ-ACK information bits are arranged according to a predetermined rule is called HARQ-ACK codebook.

[0120] - Scheduling request (SR): Information used to request UL-SCH resources.

[0121] - Hybrid Automatic Repeat Request (HARQ)-acknowledgement (ACK): A response to a downlink data packet (e.g., codeword) on the PDSCH. It indicates whether the downlink data packet was successfully received by the communication device. A HARQ-ACK 1 bit is sent in response to a single codeword, and a HARQ-ACK 2 bit is sent in response to two codewords. HARQ-ACK responses include positive ACK (simply ACK), negative ACK (NACK), DTX, or NACK / DTX. Herein, the term HARQ-ACK is used interchangeably with HARQ ACK / NACK, ACK / NACK, or A / N.

[0122] - Channel State Information (CSI): Feedback information for a downlink channel. CSI includes channel quality information (CQI), rank indicator (RI), precoding matrix indicator (PMI), CSI-RS resource indicator (CRI), SS / PBCH resource block indicator, layer indicator (LI), etc. CSI is divided into CSI part 1 and CSI part 2 according to the UCI type included in CSI. For example, CRI, RI and / or CQI for the first codeword are included in CSI part 1, and LI, PMI and CQI for the second codeword are included in CSI part 2.

[0123] - Link recovery request (LRR)

[0124] For convenience, in this specification, the PUCCH resources configured and / or instructed by the BS to the UE for HARQ-ACK, SR, and CSI transmission are referred to as HARQ-ACK PUCCH resources, SR PUCCH resources, and CSI PUCCH resources, respectively.

[0125] The PUCCH format is classified according to the UCI payload size and / or transmission length (eg, the number of symbols constituting the PUCCH resource) as follows. Please refer to Table 5 for details regarding the PUCCH format.

[0126] (0) PUCCH format 0 (PF0, F0)

[0127] - Supported UCI payload size: up to K bits (e.g., K=2)

[0128] - Number of OFDM symbols constituting a single PUCCH: 1 to X symbols (e.g., X = 2)

[0129] - Transmission structure: PUCCH format 0 consists of only UCI signal without DMRS, and the UE transmits UCI status by selecting and transmitting one of multiple sequences. For example, the UE transmits one of multiple sequences via a PUCCH with PUCCH format 0 to transmit a specific UCI to the BS. The UE transmits a PUCCH with PUCCH format 0 within the PUCCH resource for the corresponding SR setting only when transmitting a positive SR.

[0130] - The configuration for PUCCH format 0 includes the following parameters for the corresponding PUCCH resource: index for initial cyclic transition, number of symbols for PUCCH transmission, 1st symbol for PUCCH transmission.

[0131] (1) PUCCH format 1 (PF1, F1)

[0132] - Supported UCI payload size: up to K bits (e.g., K=2)

[0133] - Number of OFDM symbols constituting a single PUCCH: Y to Z symbols (e.g., Y = 4, Z = 14)

[0134] - Transmission structure: DMRS and UCI are configured / mapped to different OFDM symbols in TDM form. That is, DMRS is transmitted in a symbol where no modulation symbol is transmitted. UCI is expressed by multiplying a specific sequence (e.g., orthogonal cover code (OCC)) by a modulation (e.g., QPSK) symbol. A cyclic shift (CS) / OCC is applied to both UCI and DMRS, and code division multiplexing (CDM) is supported between multiple PUCCH resources (within the same RB) (according to PUCCH format 1). PUCCH format 1 carries UCI with a maximum size of 2 bits, and modulation symbols are spread in the time domain by an orthogonal cover code (OCC) (set differently depending on whether frequency hopping is present or not).

[0135] - The configuration for PUCCH format 1 includes the following parameters for the corresponding PUCCH resource: index for initial cyclic transition, number of symbols for PUCCH transmission, first symbol for PUCCH transmission, index for orthogonal cover code.

[0136] (2) PUCCH format 2 (PF2, F2)

[0137] - Supported UCI payload size: More than K bits (e.g., K=2)

[0138] - Number of OFDM symbols constituting a single PUCCH: 1 to X symbols (e.g., X = 2)

[0139] - Transmission structure: DMRS and UCI are configured / mapped in frequency division multiplex (FDM) form within the same symbol. The UE applies only IFFT to the coded UCI bits without DFT and transmits. PUCCH format 2 carries UCI with a bit size larger than K bits, and the modulation symbols are FDMed with DMRS and transmitted. For example, DMRS is located at symbol indexes #1, #4, #7, and #10 in a given resource block with 1 / 3 density. A pseudo noise (PN) sequence is used for the DMRS sequence. Frequency hopping is activated for 2-symbol PUCCH format 2.

[0140] - The configuration for PUCCH format 2 includes the following parameters for the corresponding PUCCH resource: number of PRBs, number of symbols for PUCCH transmission, 1st symbol for PUCCH transmission.

[0141] (3) PUCCH format 3 (PF3, F3)

[0142] - Supported UCI payload size: More than K bits (e.g., K=2)

[0143] - Number of OFDM symbols constituting a single PUCCH: Y to Z symbols (e.g., Y = 4, Z = 14)

[0144] - Transmission structure: DMRS and UCI are configured / mapped to different symbols in TDM form. UE applies DFT to coded UCI bits and transmits. PUCCH format 3 does not support UE multiplexing for the same time-frequency resource (e.g., the same PRB).

[0145] - The configuration for PUCCH format 3 includes the following parameters for the corresponding PUCCH resource: number of PRBs, number of symbols for PUCCH transmission, 1st symbol for PUCCH transmission.

[0146] (4) PUCCH Format 4 (PF4, F4)

[0147] - Supported UCI payload size: More than K bits (e.g., K=2)

[0148] - Number of OFDM symbols constituting a single PUCCH: Y to Z symbols (e.g., Y = 4, Z = 14)

[0149] - Transmission structure: DMRS and UCI are configured / mapped to different symbols in TDM format. PUCCH format 4 applies OCC before DFT and CS (or interleaved FDM, IFDM mapping) to DMRS, allowing multiplexing of up to four UEs in the same PRB. In other words, the modulation symbol of UCI is transmitted after being time division multiplexed (TDM) with DMRS.

[0150] - The configuration for PUCCH format 4 includes the following parameters for the corresponding PUCCH resource: number of symbols for PUCCH transmission, length for the orthogonal cover code, index for the orthogonal cover code, 1st symbol for PUCCH transmission.

[0151] The following table shows examples of PUCCH formats. According to the PUCCH transmission length, it is divided into short PUCCH (formats 0 and 2) and long PUCCH (formats 1, 3 and 4).

[0152] [Table 5]

[0153] PUCCH resources are determined for each UCI type (e.g., A / N, SR, CSI). The PUCCH resources used for UCI transmission are determined based on the UCI (payload) size. As an example, the BS configures multiple PUCCH resource sets for the UE, and the UE selects a specific PUCCH resource set corresponding to a specific range according to the range of the UCI (payload) size (e.g., the number of UCI bits). For example, the UE can select any of the following PUCCH resource sets according to the number of UCI bits (N UCI )

[0154] - PUCCH resource set #0, number of UCI bits ≤ 2

[0155] - PUCCH resource set #1, 2 < number of UCI bits ≤ N1

[0156] ...

[0157] - PUCCH resource set #(K - 1), N K-2 < number of UCI bits ≤ N K-1

[0158] Here, K is the number of PUCCH resource sets (K > 1), and N i is the maximum number of UCI bits supported by PUCCH resource set #i. For example, PUCCH resource set #1 is composed of resources of PUCCH format 0 - 1, and other PUCCH resource sets are composed of resources of PUCCH format 2 - 4 (see Table 5).

[0159] The configuration for each PUCCH resource includes a PUCCH resource index, an index of a starting PRB, and a configuration for one of PUCCH formats 0 to 4. The code rate for multiplexing HARQ-ACK, SR, and CSI report in a PUCCH transmission using PUCCH format 2, PUCCH format 3, or PUCCH format 4 is configured in the UE by the BS via the upper layer parameter maxCodeRate. The upper layer parameter maxCodeRate is used to determine how to feed back UCI on a PUCCH resource for PUCCH format 2, 3, or 4.

[0160] When the UCI type is SR or CSI, the PUCCH resource used for UCI transmission in the PUCCH resource set is configured in the UE by the network through higher layer signaling (e.g., RRC signaling).When the UCI type is HARQ-ACK for SPS (Semi-Persistent Scheduling) PDSCH, the PUCCH resource used for UCI transmission in the PUCCH resource set is configured in the UE by the network through higher layer signaling (e.g., RRC signaling).On the other hand, when the UCI type is HARQ-ACK for PDSCH scheduled by DCI, the PUCCH resource used for UCI transmission in the PUCCH resource set is scheduled based on the DCI.

[0161] In the case of DCI-based PUCCH resource scheduling, the BS transmits DCI to the UE via the PDCCH and can indicate the PUCCH resource to be used for UCI transmission in a specific PUCCH resource set by the ACK / NACK resource indicator (ARI) in the DCI. The ARI is used to indicate the PUCCH resource for ACK / NACK transmission and is also called the PUCCH resource indicator (PRI). Here, the DCI is the DCI used for PDSCH scheduling, and the UCI includes the HARQ-ACK for the PDSCH. In addition, the BS can configure the UE with a PUCCH resource set consisting of more PUCCH resources than the number of states that the ARI can represent, using a (UE-specific) higher layer (e.g., RRC) signal. At this time, the ARI indicates a PUCCH resource subset within the PUCCH resource set, and which PUCCH resource to use within the indicated PUCCH resource subset is determined according to an implicit rule based on transmission resource information for the PDCCH (e.g., the starting control channel element (CCE) index of the PDCCH, etc.).

[0162] A UE needs to have uplink resources available to it for UL-SCH data transmission and downlink resources available to it for DL-SCH data reception. Uplink and downlink resources are assigned to a UE by resource allocation by a BS. Resource allocation includes time domain resource allocation (TDRA) and frequency domain resource allocation (FDRA). In this specification, uplink resource allocation is also called uplink grant and downlink resource allocation is also called downlink assignment. Uplink grant is dynamically received by the UE on PDCCH or in RAR, or semi-persistently configured to the UE by RRC signaling from the BS. Downlink assignment is dynamically received by the UE on PDCCH or semi-persistently configured to the UE by RRC signaling from the BS.

[0163] In the UL, the BS can dynamically allocate uplink resources to the UE via a PDCCH addressed to a cell radio network temporary identifier (C-RNTI). The UE monitors the PDCCH to look for possible uplink grants for UL transmission. The BS can also allocate uplink resources to the UE using configured grants. Two types of configured grants are used: Type 1 and Type 2. In the case of Type 1, the BS directly provides the configured uplink grant (including periodicity) via RRC signaling. In the case of Type 2, the BS configures the periodicity of the RRC configured uplink grant via RRC signaling and signals and activates or deactivates the configured uplink grant via a PDCCH addressed to a configured scheduling RNTI (CS-RNTI). For example, in the case of Type 2, it indicates that the PDCCH addressed to the CS-RNTI can be implicitly reused according to a period set by RRC signaling until the corresponding uplink grant is deactivated.

[0164] In DL, the BS can dynamically allocate downlink resources to the UE via the PDCCH addressed to the C-RNTI. The UE monitors the PDCCH to look for possible downlink allocations. The BS can also allocate downlink resources to the UE using semi-static scheduling (SPS). The BS configures a period of the downlink allocation configured by RRC signaling, and signals and activates or deactivates the downlink allocation configured via the PDCCH addressed to the CS-RNTI. For example, the PDCCH addressed to the CS-RNTI indicates that the corresponding downlink allocation is implicitly reusable with a period configured by RRC signaling until it is deactivated.

[0165] The resource allocation by PDCCH and the resource allocation by RRC will be described in more detail below.

[0166] *Resource allocation via PDCCH: Dynamic grant / allocation

[0167] The PDCCH is used to schedule DL transmissions on the PDSCH or UL transmissions on the PUSCH. The DCI on the PDCCH that schedules DL transmissions indicates the modulation and coding format (e.g., modulation and coding scheme (MCS) index I) associated with the DL-SCH. MCSThe DCI on the PDCCH for scheduling the UL transmission includes an uplink scheduling grant including at least a modulation and coding format, a resource allocation, and HARQ information related to the UL-SCH. The HARQ information for the DL-SCH or for the UL-SCH includes a new data indicator (NDI), a transport block size (TBS), a redundancy version (RV), and a HARQ process ID (i.e., a HARQ process number). The size and use of the DCI carried by one PDCCH differ depending on the DCI format. For example, DCI format 0_0, DCI format 0_1, or DCI format 0_2 is used for scheduling the PUSCH, and DCI format 1_0, DCI format 1_1, or DCI format 1_2 is used for scheduling the PDSCH. In particular, DCI format 0_2 and DCI format 1_2 are used to schedule transmissions having higher transmission reliability and lower latency requirements than those guaranteed by DCI format 0_0, DCI format 0_1, DCI format 1_0, and DCI format 1_1. Some embodiments of the present invention may be applied to transmission of UL data based on DCI format 0_2. Some embodiments of the present invention may be applied to reception of DL data based on DCI format 1_2.

[0168] FIG. 7 shows an example of PDSCH time domain resource allocation by PDCCH and an example of PUSCH time domain resource allocation by PDCCH.

[0169] The DCI carried by the PDCCH for scheduling the PDSCH or the PUSCH includes a time domain resource assignment (TDRA) field, which provides a value m for row index m+1 into an allocation table for the PDSCH or the PUSCH. A predefined default PDSCH time domain assignment is applied as the allocation table for the PDSCH, or a PDSCH time domain resource assignment table set by the BS via RRC signaling pdsch-TimeDomainAllocationList is applied as the allocation table for the PDSCH. A predefined default PUSCH time domain assignment is applied as the allocation table for the PUSCH, or a PUSCH time domain resource assignment table set by the BS via RRC signaling pusch-TimeDomainAllocationList is applied as the allocation table for the PUSCH. The applied PDSCH time domain resource assignment table and / or the applied PUSCH time domain resource assignment table are determined by a fixed / predefined rule (e.g., see 3GPP TS38.214).

[0170] For PDSCH time domain resource configuration, each indexed row defines the DL allocation-to-PDSCH slot offset K0, the start and length indicator value SLIV (or directly the starting position of the PDSCH within the slot (e.g. starting symbol index S) and the allocation length (e.g. number of symbols L)), and the PDSCH mapping type. For PUSCH time domain resource configuration, each indexed row defines the UL grant-to-PUSCH slot offset K2, the starting position of the PUSCH within the slot (e.g. starting symbol index S) and the allocation length (e.g. number of symbols L), and the PUSCH mapping type. K0 for PDSCH or K2 for PUSCH indicates the difference between the slot where the PDCCH is located and the slot where the PDSCH or PUSCH corresponding to the PDCCH is located. SLIV is a joint indication of the starting symbol S relative to the start of the slot with the PDSCH or PUSCH and the number of consecutive symbols L counting from symbol S. For PDSCH / PUSCH mapping type, there are two mapping types: one is mapping type A and the other is mapping type B. For PDSCH / PUSCH mapping type A, a demodulation reference signal (DMRS) is mapped to a PDSCH / PUSCH resource based on the start of a slot, but one or two symbols of the PDSCH / PUSCH resource can be used as a DMRS symbol according to other DMRS parameters. For example, for PDSCH / PUSCH mapping type A, the DMRS is located at the third symbol (symbol #2) or the fourth symbol (symbol #3) in a slot according to RRC signaling. For PDSCH / PUSCH mapping type B, the DMRS is mapped based on the first OFDM symbol of the PDSCH / PUSCH resource, but one or two symbols from the first symbol of the PDSCH / PUSCH resource can be used as a DMRS symbol according to other DMRS parameters.For example, for PDSCH / PUSCH mapping type B, the DMRS is located in the first symbol allocated for PDSCH / PUSCH. In this specification, the PDSCH / PUSCH mapping type is also referred to as a mapping type or a DMRS mapping type. For example, in this specification, PUSCH mapping type A is also referred to as a mapping type A or a DMRS mapping type A, and PUSCH mapping type B is also referred to as a mapping type B or a DMRS mapping type B.

[0171] The scheduling DCI includes a frequency domain resource assignment (FDRA) field that provides assignment information regarding resource blocks used for PDSCH or PUSCH. For example, the FDRA field provides the UE with information regarding a cell for PDSCH or PUSCH transmission, information regarding a BWP for PDSCH or PUSCH transmission, and information regarding resource blocks for PDSCH or PUSCH transmission.

[0172] *Resource allocation by RRC

[0173] As mentioned above, for uplink there are two types of transmissions without dynamic grants: configured grant type 1 and configured grant type 2. For configured grant type 1, the UL grant is provided by RRC signaling and stored as configured grant. For configured grant type 2, the UL grant is provided by PDCCH and stored or removed as configured uplink grant based on L1 signaling indicating configured uplink grant activation or deactivation. Type 1 and Type 2 are configured by RRC signaling per serving cell and per BWP. Multiple configurations can be activated simultaneously on multiple different serving cells.

[0174] When grant type 1 is configured, the UE is provided with the following parameters by the BS via RRC signaling:

[0175] - cs-RNTI, which is the CS-RNTI for retransmissions;

[0176] - periodicity, the periodicity of the configured grant type 1;

[0177] - timeDomainOffset, which indicates the offset of the resource in the time domain relative to System frameNumber (SFN)=0;

[0178] - a timeDomainAllocation value m providing a row index m+1 pointing to an allocation table indicating a combination of starting symbol S, length L and PUSCH mapping type;

[0179] - frequencyDomainAllocation, which provides frequency domain resource allocation; and

[0180] - I indicating the modulation order, the target code rate and the transport block size MCS Provided by mcsAndTBS.

[0181] When RRC configures a configuration grant type 1 for a serving cell, the UE stores the UL grant provided by the RRC as the configured uplink grant for the indicated serving cell and initializes or re-initializes the configured uplink grant to start at a symbol according to timeDomainOffset and S (derived from SLIV) and to recur with periodicity. After an uplink grant is configured for configured grant type 1, the UE may consider the uplink grant to recur associated with each symbol that satisfies: [(SFN * numberOfSlotsPerFrame (numberOfSymbolsPerSlot) + (SlotNumber in the frame * numberOfSymbolsPerSlot) + symbolNumber in the slot] = (timeDomainOffset * numberOfSymbolsPerSlot + S + N * periodicity) modulo (1024 * numberOfSlotsPerFrame * numberOfSymbolsPerSlot), for all N > 0, where numberOfSlotsPerFrame and numberOfSymbolsPerSlot indicate the number of consecutive slots per frame and the number of consecutive OFDM symbols per slot, respectively (see Tables 1 and 2).

[0182] When grant type 2 is configured, the UE is provided with the following parameters by the BS via RRC signaling:

[0183] -cs-RNTI, which is the CS-RNTI for activation, deactivation and retransmission; and

[0184] - The periodicity provided for the configured grant type 2 periodicity.

[0185] The actual uplink grant is provided to the UE via the PDCCH (addressed to the CS-RNTI). After an uplink grant is configured for grant type 2, the UE considers the uplink grant to be recurrent in association with each symbol that satisfies: [(SFN*numberOfSlotsPerFrame *numberOfSymbolsPerSlot)+(SlotNumber in the frame *numberOfSymbolsPerSlot)+symbol Number in the slot]=[(SFN start time *numberOfSlotsPerFrame *numberOfSymbolsPerSlot+slot start time *numberOfSymbolsPerSlot+symbol start time )+N*periodicity] modulo (1024 *numberOfSlotsPerFrame *numberOfSymbolsPerSlot), for all N ≥ 0, where SFN start time , slot start time and symbol start time indicate the SFN, slot, and symbol of the first PUSCH transmission opportunity after the configured grant is (re-)initialized, and numberOfSlotsPerFrame and numberOfSymbolsPerSlot indicate the number of consecutive slots per frame and the number of consecutive OFDM symbols per slot, respectively (see Tables 1 and 2).

[0186] In some scenarios, the parameters harq-ProcID-Offset and / or harq-ProcID-Offset2 used to derive a HARQ process ID for the configured uplink grant are further provided by the BS to the UE. harq-ProcID-Offset is the offset of the HARQ process for the configured grant for operation with shared spectrum channel access, and harq-ProcID-Offset2 is the offset of the HARQ process for the configured grant. In this specification, cg-RetransmissionTimer is the duration during which the UE should not autonomously retransmit using the HARQ process of the (re)transmission after (re)transmission based on the configured grant, and is a parameter provided by the BS to the UE when retransmission on the configured uplink grant is configured. For a configured grant where neither harq-ProcID-Offset nor cg-RetransmissionTimer is configured, the HARQ process ID associated with the first symbol of an UL transmission is derived from the following formula: HARQ Process ID=[floor(CURRENT_symbol / periodicity)]modulo nrofHARQ-Processes.For a configured uplink grant with harq-ProcID-Offset2, the HARQ process ID associated with the first symbol of the UL transmission is derived from the following formula: HARQ Process ID=[floor(CURRENT_symbol / periodicity)] modulo nrofHARQ-Processes+harq-ProcID-Offset2, where CURRENT_symbol=(SFN*numberOfSlotsPerFrame *numberOfSymbolsPerSlot+slot number in the frame*numberOfSymbolsPerSlot+symbol number in the slot), and numberOfSlotsPerFrame and numberOfSymbolsPerSlot denote the number of consecutive slots per frame and the number of consecutive OFDM symbols per slot, respectively. For a configured UL grant with cg-RetransmissionTimer, the UE may arbitrarily select a HARQ process ID among the HARQ process IDs available for configuration of the configured grant.

[0187] For downlink, the UE is configured with semi-persistent scheduling (SPS) per serving cell and per BWP by RRC signaling from the BS. For DL ​​SPS, the DL allocation is provided to the UE by PDCCH and is stored or removed based on L1 signaling indicating SPS activation or deactivation. When SPS is configured, the UE is provided with the following parameters from the BS by RRC signaling (e.g. SPS configuration) used to configure semi-persistent transmission:

[0188] -cs-RNTI, which is the CS-RNTI for activation, deactivation and retransmission;

[0189] -nrofHARQ-Processes, providing the number of configured HARQ processes for SPS;

[0190] -periodicity, which provides the periodicity of the configured downlink allocation for SPS.

[0191] -n1PUCCH-AN providing HARQ resources for PUCCH for SPS (the network configures HARQ resources as format 0 or format 1, and the actual PUCCH-resources are configured in PUCCH-Config and referred to in n1PUCCH-AN by their ID).

[0192] Multiple downlink SPS configurations can be configured within the BWP of the serving cell. After a downlink allocation is configured for SPS, the UE can consecutively consider the Nth downlink allocation to occur in a slot that satisfies: (numberOfSlotsPerFrame*SFN+slotNumber in the frame)=[(numberOfSlotsPerFrame*SFN start time +slot start time )+N*periodicity *numberOfSlotsPerFrame / 10] modulo (1024 *numberOfSlotsPerFrame), where SFN start time and slot start time where numberOfSlotsPerFrame and numberOfSymbolsPerSlot indicate the SFN, slot, and symbol, respectively, of the first transmission of the PDSCH after the configured downlink allocation has been (re-)initialized, and numberOfSlotsPerFrame and numberOfSymbolsPerSlot indicate the number of consecutive slots per frame and consecutive OFDM symbols per slot, respectively (see Tables 1 and 2).

[0193] In some scenarios, the UE is further provided by the BS with a parameter harq-ProcID-Offset, which is used to derive the HARQ process ID for the configured downlink allocation. harq-ProcID-Offset is the offset of the HARQ process for SPS. For configured downlink allocations without harq-ProcID-Offset, the HARQ process ID associated with the slot where DL transmission starts is determined from the following formula: HARQ Process ID=[floor(CURRENT_slot*10 / (numberOfSlotsPerFrame*periodicity))] modulo nrofHARQ-Processes, where CURRENT_slot=[(SFN*numberOfSlotsPerFrame)+slot number in the frame] and numberOfSlotsPerFrame means the number of consecutive slots per frame. For a configured downlink allocation with harq-ProcID-Offset, the HARQ process ID associated with the slot where DL transmission starts is determined by the following formula: HARQ Process ID=[floor(CURRENT_slot / periodicity)] modulo nrofHARQ-Processes+harq-ProcID-Offset, where CURRENT_slot=[(SFN*numberOfSlotsPerFrame)+slot number in the frame] and numberOfSlotsPerFrame means the number of consecutive slots per frame.

[0194] If the cyclic redundancy check (CRC) of the corresponding DCI format is scrambled with the CS-RNTI provided by the RRC parameter cs-RNTI and the new data indicator field for an enabled transport block is set to 0, the UE validates the DL SPS assigned PDCCH or the configured UL grant type 2 PDCCH for scheduling activation or descheduling. The validation of the DCI format is achieved when all fields for the DCI format are set according to Table 6 or Table 7. Table 6 illustrates specific fields for DL ​​SPS and UL grant type 2 scheduling activation PDCCH validation validation, and Table 7 illustrates specific fields for DL ​​SPS and UL grant type 2 descheduling PDCCH validation validation.

[0195] [Table 6]

[0196] [Table 7]

[0197] The actual DL allocation or UL grant for DL ​​SPS or UL grant type 2 and the corresponding modulation and coding scheme are provided by resource allocation fields (e.g., TDRA field providing TDRA value m, FDRA field providing frequency resource block allocation, modulation and coding scheme field) in the DCI format carried by the scheduling activation PDCCH of the corresponding DL SPS or UL grant type 2. If a valid confirmation is achieved, the UE considers the information in the DCI format as a valid activation or deactivation of the DL SPS or the configured UL grant type 2.

[0198] In this specification, a PDSCH based on DL SPS is also referred to as an SPS PDSCH, a PUSCH based on UL CG is also referred to as a CG PUSCH, a PDSCH dynamically scheduled by DCI carried by a PDCCH is also referred to as a DG PDSCH, and a PUSCH dynamically scheduled by DCI carried by a PDCCH is also referred to as a DG PUSCH.

[0199] FIG. 8 illustrates the HARQ-ACK transmission / reception process.

[0200] 8, the UE detects the PDCCH in slot n. Then, the UE receives the PDSCH in slot n+K0 according to the scheduling information received through the PDCCH in slot n, and transmits UCI through the PUCCH in slot n+K1. Here, the UCI includes a HARQ-ACK response to the PDSCH.

[0201] The DCI (eg, DCI format 1_0, DCI format 1_1) carried by the PDCCH that schedules the PDSCH includes the following information:

[0202] Frequency domain resource assignment (FDRA): Indicates the RB set allocated to the PDSCH.

[0203] - Time domain resource assignment (TDRA): Indicates DL assignment-to-PDSCH slot offset K0, starting position (e.g., symbol index S) and length (e.g., number of symbols L) of the PDSCH within the slot, and PDSCH mapping type. PDSCH mapping type A or PDSCH mapping type B is indicated by TDRA. For PDSCH mapping type A, the DMRS is located at the third symbol (symbol #2) or the fourth symbol (symbol #3) in the slot. For PDSCH mapping type B, the DMRS is located at the first symbol allocated for the PDSCH.

[0204] -PDSCH-to-HARQ_feedback timing indicator: indicates K1.

[0205] If the PDSCH is configured to transmit up to one TB, the HARQ-ACK response consists of 1 bit. If the PDSCH is configured to transmit up to two transport blocks (TBs), the HARQ-ACK response consists of 2 bits if spatial bundling is not configured, and consists of 1 bit if spatial bundling is configured. If the HARQ-ACK transmission time for multiple PDSCHs is specified as slot n+K1, the UCI transmitted in slot n+K1 includes the HARQ-ACK responses for multiple PDSCHs.

[0206] In this specification, a HARQ-ACK payload consisting of HARQ-ACK bits for one or more PDSCHs is also referred to as a HARQ-ACK codebook. HARQ-ACK codebooks are classified into i) semi-static HARQ-ACK codebooks, ii) dynamic HARQ-ACK codebooks, and iii) HARQ process-based HARQ-ACK codebooks according to the manner in which the HARQ-ACK payload is determined.

[0207] In the case of a semi-static HARQ-ACK codebook, parameters related to the HARQ-ACK payload size reported by the UE are semi-statically configured by a (UE-specific) higher layer (e.g., RRC) signal. For example, the size of the HARQ-ACK payload in the semi-static HARQ-ACK codebook is determined based on the number of HARQ-ACK bits corresponding to the combination (hereinafter, bundling window) of all DL carriers (i.e., DL serving cells) configured in the UE and all DL scheduling slots (or PDSCH transmission slots or PDCCH monitoring slots) to which the HARQ-ACK transmission timing is indicated, based on the (maximum) HARQ-ACK payload (size) transmitted via one PUCCH in one slot. That is, the semi-static HARQ-ACK codebook method is a method in which the size of the HARQ-ACK codebook is fixed (to the maximum value) regardless of the number of DL data actually scheduled. For example, DL grant DCI (PDCCH) includes PDSCH to HARQ-ACK timing information, and the PDSCH-to-HARQ-ACK timing information has one of a plurality of values ​​(e.g., k). For example, if PDSCH is received in slot #m and PDSCH to HARQ-ACK timing information in DL grant DCI (PDCCH) scheduling PDSCH indicates k, HARQ-ACK information for PDSCH is transmitted in slot #(m+k). As an example, k ∈ {1, 2, 3, 4, 5, 6, 7, 8} is given. On the other hand, if HARQ-ACK information is transmitted in slot #n, the HARQ-ACK information includes the maximum possible HARQ-ACK based on the bundling window. That is, the HARQ-ACK information of slot #n includes the HARQ-ACK corresponding to slot #(nk). For example, if k∈{1, 2, 3, 4, 5, 6, 7, 8}, the HARQ-ACK information of slot #n includes HARQ-ACKs corresponding to slot #(n-8) to slot #(n-1) regardless of actual DL data reception (i.e., the maximum number of HARQ-ACKs). Here, the HARQ-ACK information can be replaced with a HARQ-ACK codebook and a HARQ-ACK payload.Also, the slots can be understood / replaced as candidate occasions for DL ​​data reception. As illustrated, the bundling window is determined based on the PDSCH-to-HARQ-ACK timing with respect to the HARQ-ACK slot, and the PDSCH-to-HARQ-ACK timing set has a predefined value (e.g., {1, 2, 3, 4, 5, 6, 7, 8}) or is set by higher layer (RRC) signaling. The semi-static HARQ-ACK codebook is also referred to as a type-1 HARQ-ACK codebook. In the case of a type-1 HARQ-ACK codebook, the number of bits to be transmitted in the HARQ-ACK report is fixed and may be large. If many cells are configured but only a few cells are scheduled, the type-1 HARQ-ACK codebook is inefficient.

[0208] In addition, in the case of a dynamic HARQ-ACK codebook, the HARQ-ACK payload size reported by the UE can be dynamically changed according to DCI, etc. The dynamic HARQ-ACK codebook is also called a type-2 HARQ-ACK codebook. The type-2 HARQ-ACK codebook is a more optimized HARQ-ACK feedback because the UE sends feedback only to the scheduled serving cells. In addition, in a bad channel state, the UE may erroneously grasp the number of scheduled serving cells, and in order to solve this, the DAI is included as part of the DCI. For example, in the dynamic HARQ-ACK codebook method, the DL scheduling DCI includes a counter-DAI (i.e., c-DAI) and / or a total-DAI (i.e., t-DAI). Here, DAI means a downlink assignment index, and is used by the BS to inform the UE of the transmitted or scheduled PDSCH included in one HARQ-ACK transmission. In particular, c-DAI is an index indicating the order between PDCCHs carrying DL scheduling DCI (hereinafter, DL scheduling PDCCHs), and t-DAI is an index indicating the total number of DL scheduling PDCCHs up to the current slot in which a PDCCH having t-DAI is present.

[0209] Meanwhile, in the case of a HARQ process-based HARQ-ACK codebook, the HARQ-ACK payload is determined based on all HARQ processes of all configured (or activated) serving cells in a PUCCH group. For example, the HARQ-ACK payload size reported by the UE through the HARQ process-based HARQ-ACK codebook is determined by the number of all configured or activated serving cells in a PUCCH group configured in the UE and the number of HARQ processes for the serving cells. The HARQ process-based HARQ-ACK codebook is also called a type-3 HARQ-ACK codebook. The type-3 HARQ-ACK codebook can be applied to one-shot feedback.

[0210] Figure 9 shows an example of multiplexing UCI onto PUSCH. When PUCCH and PUSCH resources are superimposed in a slot and simultaneous transmission of PUCCH-PUSCH is not set, UCI is transmitted by PUSCH as shown in the figure. Transmitting UCI by PUSCH is called UCI piggyback or PUSCH piggyback. Figure 9 shows an example of HARQ-ACK and CSI carried on PUSCH resources.

[0211] When multiple UL channels overlap within a given time interval, in order for the BS to accurately receive the UL channel transmitted by the UE, it is necessary to define a method for the UE to handle multiple UL channels. The following describes a method for handling collisions between UL channels.

[0212] FIG. 10 illustrates an example of a process for handling collisions between UL channels by a UE with overlapping PUCCH in a single slot.

[0213] For UCI transmission, the UE determines a PUCCH resource for each UCI. Each PUCCH resource is defined by a start symbol and a transmission length. When PUCCH resources for PUCCH transmission are overlapped in a single slot, the UE performs UCI multiplexing based on the PUCCH resource with the earliest start symbol. For example, the UE determines a PUCCH resource (hereinafter, PUCCH resource B) to be overlapped (in time) based on the PUCCH resource (hereinafter, PUCCH resource A) with the earliest start symbol in a slot (S1001). The UE applies a UCI multiplexing rule to the PUCCH resource A and the PUCCH resource B. For example, based on the UCI A of the PUCCH resource A and the UCI B of the PUCCH resource B, a MUX UCI including all or part of the UCI A and the UCI B is obtained according to the UCI multiplexing rule. The UE determines a single PUCCH resource (hereinafter, MUX PUCCH resource) to multiplex UCI associated with the PUCCH resource A and the PUCCH resource B (S1003). For example, the UE determines a PUCCH resource set (hereinafter, PUCCH resource set X) corresponding to the payload size of the MUX UCI from among PUCCH resource sets configured or available to the UE, and determines one of the PUCCH resources belonging to PUCCH resource set X as the MUX PUCCH resource. For example, the UE determines one of the PUCCH resources belonging to PUCCH resource set X as the MUX PUCCH resource using a PUCCH resource indicator field in the last DCI among DCIs having a PDSCH-to-HARQ_feedback timing indicator field indicating the same slot for PUCCH transmission. The UE determines the total number of PRBs of the MUX PUCCH resource based on the payload size of the MUX UCI and the maximum code rate for the PUCCH format of the MUX PUCCH resource.If the MUX PUCCH resource overlaps with other PUCCH resources (except PUCCH resource A and PUCCH resource B), the UE repeats the above-mentioned operations based on the MUX PUCCH resource (or the PUCCH resource with the earliest start symbol among the remaining PUCCH resources including the MUX PUCCH resource).

[0214] FIG. 11 illustrates a case where UCI multiplexing is performed according to FIG. 10. Referring to FIG. 11, when multiple PUCCH resources are overlapped in a slot, UCI multiplexing is performed based on the earliest PUCCH resource A (e.g., the start symbol is the earliest). In FIG. 11, cases 1 and 2 illustrate a case where the first PUCCH resource overlaps with other PUCCH resources. In this case, the process of FIG. 10 is performed with the first PUCCH resource regarded as the earliest PUCCH resource A. On the other hand, case 3 illustrates a case where the first PUCCH resource does not overlap with other PUCCH resources, and the second PUCCH resource overlaps with other PUCCH resources. In case 3, UCI multiplexing is not performed for the first PUCCH resource. Instead, the process of FIG. 10 is performed with the second PUCCH resource regarded as the earliest PUCCH resource A. Case 2 is a case where a MUX PUCCH resource determined to transmit multiplexed UCI is newly overlapped with other PUCCH resources. In this case, the MUX PUCCH resource (or the earliest PUCCH resource (eg, the PUCCH resource having the earliest start symbol among the remaining PUCCHs including the MUX PUCCH resource)) is regarded as the earliest PUCCH resource A, and the process of FIG.

[0215] FIG. 12 illustrates an example of a process for handling collisions between UL channels by a UE having overlapping PUCCH and PUSCH in a single slot.

[0216] The UE determines a PUCCH resource for UCI transmission (S1201). Determining the PUCCH resource for UCI includes determining a MUX PUCCH resource. In other words, the UE determines the PUCCH resource for UCI includes determining a MUX PUCCH resource based on multiple PUCCHs overlapping in a slot.

[0217] The UE performs UCI piggybacking on the PUSCH resource based on the determined (MUX) PUCCH resource (S1203). For example, when a PUSCH resource (for which multiplexed UCI transmission is permitted) exists, the UE applies the UCI multiplexing rule to the PUCCH resource that overlaps (in time) with the PUSCH resource. The UE transmits UCI via the PUSCH.

[0218] If there is no PUSCH within the slot that overlaps with the determined PUCCH resource, S1203 is omitted and the UCI is transmitted by the PUCCH.

[0219] On the other hand, if the determined PUCCH resource overlaps with multiple PUSCHs in the time axis, the UE multiplexes the UCI onto one of the multiple PUSCHs. For example, if the UE intends to transmit multiple PUSCHs on respective serving cells, the UE multiplexes the UCI onto the PUSCH of a specific serving cell (e.g., the serving cell with the smallest serving cell index) among the serving cells. If there is more than one PUSCH in a slot on a specific serving cell, the UE multiplexes the UCI onto the earliest PUSCH to be transmitted in the slot.

[0220] Figure 13 illustrates UCI multiplexing considering time line conditions. When a UE performs UCI and / or data multiplexing for PUCCH and / or PUSCH overlapping on a time axis, the UE may have insufficient processing time for UCI and / or data multiplexing due to flexible UL timing configuration for PUCCH or PUSCH. In order to prevent the UE from having insufficient processing time, the following two time line conditions (hereinafter, multiplexing time line conditions) are considered in the process of multiplexing UCI / data for PUCCH and / or PUSCH overlapping (on a time axis).

[0221] (1) The last symbol of the PDSCH corresponding to the HARQ-ACK information is received (in time) T1 before the start symbol of the earliest channel among the overlapping PUCCH and / or PUSCH. T1 is a number that is determined by i) the minimum PDSCH processing time N1 defined by the UE processing capability, ii) d, which is predefined to be an integer value equal to or greater than 0 depending on the scheduled symbol position, PDSCH mapping type, BWP switching, etc. 1,1 It is determined based on the following:

[0222] For example, T1 is determined as follows: T1=(N1+d 1,1 )*(2048+144)*κ*2 -u *T c N1 is based on u in Tables 8 and 9 for UE processing capabilities #1 and #2, respectively, where u is (u PDCCH , u PDSCH , u UL ), the one that yields the largest T1, where u PDCCH corresponds to the subcarrier spacing of the PDCCH that schedules the PDSCH, and u PDSCH corresponds to the subcarrier spacing of the scheduled PDSCH, and u UL corresponds to the subcarrier spacing of the UL channel where the HARQ-ACK is transmitted, and κ=T c / T f = 64. In Table 8, N 1,0 In the case where the PDSCH DMRS position of the additional DMRS is l1=12, N1,0 = 14, otherwise, N 1,0 = 13 (see section 7.4.1.1.2 of 3GPP TS38.211). For PDSCH mapping type A, if the last symbol of the PDSCH is on the i-th slot of the slots, then d 1,1 = 7-i, otherwise, d 1,1 If the PDSCH is mapping type B for UE processing capability #1, then d1=0 if the number of allocated PDSCH symbols is 7, and d 1,1 = 3 and the number of allocated PDSCH symbols is 2, then d 1,1 = 3 + d, where d is the number of overlapping symbols of the scheduled PDCCH and the scheduled PDSCH. If the PDSCH is mapping type B for UE processing capability #2, and the number of assigned PDSCH symbols is 7, then d 1,1 = 0 and the number of allocated PDSCH symbols is 4, then d 1,1 is the number of overlapping symbols of the scheduled PDCCH and the scheduled PDSCH. If the number of allocated PDSCH symbols is 2, the scheduled PDSCH is within the 3-symbol CORESET, and the CORESET and the PDSCH have the same starting symbol, then d 1,1 = 3, otherwise, d 1,1 is the number of overlapping symbols of the scheduled PDCCH and the scheduled PDSCH. In this specification, T1 is also written as T_proc,1.

[0223] (2) The last symbol of the PDCCH indicating (e.g., triggering) a PUCCH or PUSCH transmission is received T2 before the start symbol of the earliest PUCCH and / or PUSCH channel that overlaps it (in time). T2 is determined by i) the minimum PUSCH preparation time N2 defined by the UE PUSCH timing capability, and / or ii) a predefined integer value d equal to or greater than 0 depending on the scheduled symbol position or BWP switching, etc. 2,X It is decided based on the following. 2,X is related to the position of the scheduled symbol d 2,1 and BWP switching related d 2,2 It is divided into:

[0224] For example, T2 is determined as follows: T2=max{(N2+d 2,1 )*(2048+144)*κ*2 -u *T c +T ext +T switch , d 2,2}. N2 is based on u in Tables 10 and 11 for UE Timing Capabilities #1 and #2, respectively, where u is (u DL , u UL ), which is the one that yields the largest T2, where u DL corresponds to the subcarrier spacing of the PDCCH carrying the DCI that schedules the PUSCH, and u UL corresponds to the subcarrier spacing of the PUSCH, and κ=T c / T f = 64. If the first symbol of the PUSCH allocation consists of only DM-RS, then d 2,1 = 0, otherwise, d 2,1 = 1. When the scheduling DCI triggers a change in the BWP, d 2,2 is equal to the switching time, otherwise, d 2,2=0. The switching time is defined differently for different frequency ranges. For example, the switching time is 0.5 ms for frequency range FR1 and 0.25 ms for frequency range FR2. In this specification, T2 is also denoted as T_proc,2.

[0225] The following tables illustrate processing times according to UE processing capabilities. In particular, Table 8 illustrates the PDSCH processing times for UE PDSCH processing capability #1, Table 9 illustrates the PDSCH processing times for UE PDSCH processing capability #2, Table 10 illustrates the PUSCH preparation times for UE PUSCH timing capability #1, and Table 11 illustrates the PUSCH preparation times for UE timing capability #2.

[0226] [Table 8]

[0227] [Table 9]

[0228] [Table 10]

[0229] [Table 11]

[0230] The UE reports to the BS the PDSCH processing capability supported by the UE for a carrier corresponding to one band entry in a band combination. For example, the UE reports as UE capability whether the UE supports only PDSCH processing capability #1 or supports PDSCH processing capability #2 for each SCS supported in the band. The UE reports to the BS the PUSCH processing capability supported by the UE for a carrier corresponding to one band entry in a band combination. For example, the UE reports as UE capability whether the UE supports only PUSCH processing capability #1 or supports PUSCH processing capability #2 for each SCS supported in the band.

[0231] When a UE configured to multiplex different UCI types in one PUCCH is to transmit multiple overlapping PUCCHs in a slot, or when a UE is to transmit overlapping PUCCHs and PUSCHs in a slot, the UE can multiplex the UCI types if a certain condition is satisfied. The certain condition includes a multiplexing time line condition. For example, in FIG. 10 to FIG. 12, the PUCCHs and PUSCHs to which UCI multiplexing is applied are UL channels that satisfy the multiplexing time line condition. Referring to FIG. 13, the UE needs to transmit multiple UL channels (e.g., UL channels #1 to #4) in the same slot. Here, UL CH#1 is a PUSCH scheduled by PDCCH#1. Also, UL CH#2 is a PUCCH for transmitting HARQ-ACK for PDSCH. PDSCH is scheduled by PDCCH#2, and the resource of UL CH#2 is also indicated by PDCCH#2.

[0232] In this case, if the UL channels (e.g., UL channels #1 to #3) to be superimposed on the time axis satisfy the multiplexing time line condition, the UE can perform UCI multiplexing on the UL channels #1 to #3 to be superimposed on the time axis. For example, the UE checks whether the last symbol of the PDSCH to the first symbol of the UL CH #3 satisfies the T1 condition. Also, the UE checks whether the last symbol of the PDCCH #1 to the first symbol of the UL CH #3 satisfies the T2 condition. If the multiplexing time line condition is satisfied, the UE performs UCI multiplexing on the UL channels #1 to #3. On the other hand, if the earliest UL channel (e.g., the UL channel with the earliest start symbol) among the superimposed UL channels does not satisfy the multiplexing time line condition, the UE is not allowed to multiplex all the corresponding UCI types.

[0233] In some scenarios, it is specified that the UE is not expected to transmit PUCCH with HARQ-ACK information in more than one slot. Thus, according to this scenario, the UE can transmit at most one PUCCH with HARQ-ACK information in one slot. In order to prevent the occurrence of a situation where the UE cannot transmit HARQ-ACK information due to the constraint on the number of HARQ-ACK PUCCHs that the UE can transmit, the BS needs to perform downlink scheduling so that the HARQ-ACK information is multiplexed in one PUCCH resource. However, in the case of a service that requires strict latency and reliability requirements such as URLLC service, a method in which multiple HARQ-ACK feedbacks are concentrated in only one PUCCH in a slot is not preferable from the viewpoint of PUCCH performance. Furthermore, in order to support latency-critical services, the BS may be required to schedule multiple consecutive PDSCHs with a short duration in one slot. Even if the BS configures / instructs the UE to transmit PUCCH at any symbol in a slot, if only one HARQ-ACK PUCCH transmission is allowed in a slot, the BS cannot quickly schedule PDSCH back-to-back and the UE cannot quickly perform HARQ-ACK feedback. Therefore, for more flexible and efficient resource usage and service support, multiple HARQ-ACK PUCCHs (or PUSCHs) (which do not overlap with each other) can be allowed to be transmitted in one slot. Therefore, in some scenarios, PUCCH feedback based on sub-slots consisting of less than 14 OFDM symbols (e.g., 2 to 7) is considered, in addition to PUCCH feedback based on a slot consisting of 14 OFDM symbols.

[0234] The UL channels are scheduled or triggered with different priorities. In some implementations of the present invention, the priority of the UL channel may be represented by a priority index, and a UL channel with a higher priority index may be determined to be of higher priority than a UL channel with a lower priority index. In some implementations, the priority of the UL channel is provided by a DCI that schedules or triggers the transmission of the UL channel, or an RRC configuration for a grant configured for the UL channel. If a priority (or priority index) for the UL channel is not provided to the UE, the priority of the UL channel is defined to be low priority (or priority index 0).

[0235] Separate codebooks are formed / generated for HARQ-ACK feedback for multiple DL data channels (e.g., multiple PDSCHs) with different service types and / or QoS and / or latency requirements and / or reliability requirements and / or priorities. For example, a HARQ-ACK codebook for a PDSCH associated with a high priority and a HARQ-ACK codebook for a PDSCH associated with a low priority are configured / formed separately. For HARQ-ACK feedback for PDSCHs with different priorities, different parameter and resource configurations are possible for each PUCCH transmission for different priorities (see, for example, information element (IE) pucch-ConfigurationList in 3GPP TS 38.331). For example, when a UE is provided with pdsch-HARQ-ACK-CodebookList by RRC signaling, the UE is instructed to generate one or more HARQ-ACK codebooks by pdsch-HARQ-ACK-CodebookList. If the UE is instructed to generate one HARQ-ACK codebook, the HARQ-ACK codebook is associated with the PUCCH with priority index 0. If the UE is provided with a pdsch-HARQ-ACK-CodebookList, the UE only multiplexes HARQ-ACK information associated with the same priority index into the same HARQ-ACK codebook. If the UE is instructed to generate two HARQ-ACK codebooks, the first HARQ-ACK codebook is associated with the PUCCH with priority index 0 and the second HARQ-ACK codebook is associated with the PUCCH with priority index 1.

[0236] The unit of the time difference between PUCCH transmissions for HARQ-ACK feedback transmission from DL data channel (e.g., PDSCH-to-HARQ_feedback timing indicator) is determined by the length of a given subslot (e.g., the number of symbols constituting a subslot). For example, the unit of the time difference from DL data channel to PUCCH for HARQ-ACK feedback transmission is set by the parameter "subslotLengthForPUCCH" in PUCCH-Config, which is configuration information used to configure UE-specific PUCCH parameters. According to this scenario, the length unit of the PDSCH-to-HARQ feedback timing indicator is set for each HARQ-ACK codebook.

[0237] In some scenarios, uplink or downlink scheduling is performed dynamically or semi-statically, and the BS sets or instructs the UE the transmission direction (e.g., downlink, uplink, or flexible) of each symbol semi-statically using a tdd-UL-DL-ConfigurationCommon or tdd-UL-DL-ConfigurationDedicated message, or dynamically using DCI format 2_0. The uplink or downlink scheduling set in this manner may be cancelled depending on the transmission direction set / instructed in this manner.

[0238] In some scenarios, uplink or downlink scheduling is performed dynamically or semi-statically, and the BS sets or instructs the UE the transmission direction (e.g., downlink, uplink, or flexible) of each symbol semi-statically using a tdd-UL-DL-ConfigurationCommon or tdd-UL-DL-ConfigurationDedicated message, or dynamically using DCI format 2_0. The uplink or downlink scheduling set in this manner may be cancelled depending on the transmission direction set / instructed in this manner.

[0239] FIG. 14 shows an example of HARQ-ACK deferral.

[0240] In some scenarios (e.g., 3GPP NR Rel-16), when a PDSCH is scheduled for a UE by a BS, a PUCCH carrying a HARQ-ACK for the PDSCH (hereinafter, HARQ-ACK PUCCH) is transmitted at a time designated by the scheduling information for the PDSCH. However, this series of operations causes the UE to always transmit the PUCCH after a predetermined time has elapsed after receiving a semi-statically configured SPS PDSCH, and a TDD pattern that is not aligned with the period of the SPS PDSCH is used, or the PUCCH transmission is easily canceled due to the dynamic TDD operation of the BS, and the PDSCH transmission related to the canceled PUCCH transmission is also canceled or retransmission is requested. Therefore, in order to solve this problem, an operation in which the UE deferred (defer), i.e., delayed, the PUCCH timing determined for the PDSCH in a predetermined or arbitrary manner is considered. For example, when a PUCCH configured for HARQ-ACK (hereinafter, SPS HARQ-ACK) transmission of an SPS PDSCH is cancelled by a set or indicated transmission direction, a HARQ-ACK deferral is considered, which postpones the HARQ-ACK transmission after the originally expected time. With reference to FIG. 14, for example, an SPS PDSCH in slot #m-1 uses a HARQ process #i, and a HARQ-ACK transmission for the SPS PDSCH is scheduled in slot #m, but the UE decides to postpone the PUCCH in slot #m for the HARQ-ACK transmission for the SPS PDSCH to slot #n based on a predetermined condition. This HARQ-ACK deferral allows the UE and the BS to transmit / receive HARQ-ACK information for the SPS PDSCH after this, even if the PUCCH transmission is cancelled.

[0241] Meanwhile, in some scenarios (e.g., LTE-based systems or NR Rel-16-based systems), the component carrier (CC) (i.e., serving cell) used by the UE for PUCCH transmission is semi-statically set via RRC signaling of the BS. In some scenarios, it is considered that the CC on which the UE transmits the PUCCH is dynamically or semi-statically changed according to a predetermined rule, by the UE deciding arbitrarily or via L1 signaling of the BS, so that the UE's PUCCH transmission can be transmitted as soon as possible. In this specification, changing the CC also means changing the cell that contains this CC. In other words, in this specification, carrier switching may mean changing a cell to another cell, or may mean changing a carrier within one cell.

[0242] Figure 15 shows an example of PUCCH cell switching. For convenience of explanation, Figure 15 illustrates a case where the cell in which the PDSCH is transmitted is different from the candidate PUCCH cell for PUCCH cell switching, and the subcarrier spacing of the cell in which the PDSCH is transmitted is different from the subcarrier spacing of the candidate PUCCH cell, but the PDSCH may be transmitted in the candidate PUCCH cell, and the subcarrier spacing of the cell in which the PDSCH is transmitted may be the same as the subcarrier spacing of the candidate PUCCH cell.

[0243] In some implementations of this specification, when a UE is capable of using multiple CCs, the UE changes the PUCCH transmission carrier (e.g., PUCCH cell) according to a predefined rule or changes the PUCCH transmission carrier (e.g., PUCCH cell) according to L1 signaling provided by the BS so that the UE can continue uplink transmission.

[0244] In some implementations, the UE selects PUCCH resources using a set of HARQ-ACK feedback timing values ​​(e.g., dl-DataToUL-ACK, dl-DataToUL-ACK-r16, dl-DataToUL-ACK-DCI-1-2-r16) configured in the primary cell of the PUCCH group in which the PDSCH is scheduled. For example, the UE determines the HARQ-ACK feedback timing value K for the PDSCH based on the set of HARQ-ACK feedback timing values ​​configured in the Pcell if the PUCCH group in which the PDSCH is scheduled is the MCG, the set of HARQ-ACK feedback timing values ​​configured in the PSCell of the SCG if the PUCCH group in which the PDSCH is scheduled is the SCG, the set of HARQ-ACK feedback timing values ​​configured in the Pcell if the PUCCH group is the primary PUCCH group, and the set of HARQ-ACK feedback timing values ​​configured in the PUCCH-SCell of the secondary PUCCH group if the PUCCH group is the secondary PUCCH group.

[0245] Referring to FIG. 15, if PUCCH cell change is not configured, supported, or indicated, e.g., DL slot n D For a PDSCH reception ending in , the UE transmits a PUCCH including HARQ-ACK information for the PDSCH reception in UL slot n+k of the primary cell (e.g., cell A in FIG. 15 ), where slot n is slot n Dk is the last slot for PUCCH transmission overlapping with, where k is provided by the determined HARQ-ACK feedback timing value K. In some implementations, the determined HARQ-ACK feedback timing value K is counted based on the slot of the primary cell. Meanwhile, when a PUCCH cell change is configured, supported, or indicated, the PUCCH cell is determined according to a predefined / configured rule or according to L1 signaling for the slot of the determined primary cell based on the determined HARQ-ACK feedback timing value K. For example, referring to FIG. 15, when a PUCCH cell change is configured, supported, or indicated and the PUCCH cell for slot n+2 is determined to be cell B according to a predefined / configured rule or according to L1 signaling, the UE does not transmit PUCCH for PDSCH in slot n+2 on cell A, but transmits PUCCH for PDSCH in the earliest slot m of the slots of cell B overlapping with n+2 on cell A.

[0246] As described above, in order to solve the problem of HARQ-ACK of SPS PDSCH that cannot be transmitted in a TDD environment and the long delay time that can occur in a TDD environment, HARQ-ACK transmission deferral and PUCCH carrier change are considered. That is, HARQ-ACK deferral and PUCCH cell change are considered so that PUCCH transmission can be performed as soon as possible to the UE. Dynamically changing the PUCCH carrier or deferring HARQ-ACK transmission has in common that uplink transmission in resources that cannot be used for transmission due to TDD operation is performed in other available resources. Therefore, the time when HARQ-ACK transmission deferral (i.e., HARQ-ACK deferral) and PUCCH carrier change (i.e., PUCCH cell change) are requested may be the same. Since the effects obtained from HARQ-ACK deferral and PUCCH cell change are similar, it may be preferable for the UE and BS to perform one of the operations at the time when HARQ-ACK deferral and PUCCH cell change are requested. For example, if the UE can perform HARQ-ACK postponement and PUCCH cell change in a slot where HARQ-ACK transmission is not possible, by only performing PUCCH cell change, the HARQ-ACK can be transmitted with a lower delay time without postponing the HARQ-ACK transmission time. Alternatively, the UE can only postpone the HARQ-ACK and consider the impact of the PUCCH cell change during the process of postponing the HARQ-ACK.

[0247] However, for a UE that supports both HARQ-ACK postponement and PUCCH cell change, consideration must be given to the BS's operation method when selecting one of these operations, and when the UE independently decides between these two operations.

[0248] Hereinafter, an embodiment of the present specification will be described in which the UE can dynamically change the carrier for transmitting the PUCCH every PUCCH transmission via L1 signaling (e.g., DCI) of the BS or by the UE (arbitrarily or according to a predetermined rule) and the UE can postpone the HARQ-ACK transmission of the SPS PDSCH to a later time according to the TDD configuration, and a lower delay time is obtained by mixing these two methods. For example, an embodiment of the present specification will be described in which the HARQ-ACK is transmitted in an earlier slot in consideration of the PUCCH cell change in the HARQ-ACK postponement operation.

[0249] In some implementations of this specification, when the UE can use multiple CCs, the UE changes the PUCCH transmission carrier (PUCCH carrier change) and postpones the HARQ-ACK transmission that cannot be transmitted due to TDD operation (HARQ-ACK postponement) according to a predefined rule so that the UE can continue uplink transmission. In this case, the UE, in some implementations of this specification, determines whether to perform a PUCCH carrier change or a HARQ-ACK postponement for uplink transmission configured / indicated on unavailable resources based on the TDD configuration and carrier aggregation (CA) configuration, and also determines the PUCCH carrier and PUCCH resource to be used for each operation.

[0250] When HARQ-ACK postponement is performed, the UE postpones HARQ-ACK transmission from the initially specified / configured HARQ-ACK transmission slot (hereinafter, initial slot) to another slot thereafter (hereinafter, target slot).

[0251] When a UE is configured with an SCG, the UE may apply some embodiments of the present invention described below to both the MCG and the SCG. When some embodiments of the present invention described below are applied to an MCG, the terms "secondary cell", "secondary cells", "serving cell", and "serving cells" may refer to a secondary cell, secondary cells, serving cell, and serving cells belonging to an MCG, respectively. When some embodiments of the present invention described below are applied to an SCG, the terms "secondary cell", "secondary cells", "serving cell", and "serving cells" may refer to a secondary cell, secondary cells, serving cell, and serving cells belonging to the SCG, respectively. Hereinafter, the term "primary cell" may refer to a PCell of an MCG when some embodiments of the present invention are applied to an MCG, and may refer to a PSCell of an SCG when some embodiments of the present invention are applied to an SCG.

[0252] When a UE is configured with a PUCCH-SCell, the UE may apply some embodiments of the present invention described below to both the primary PUCCH group and the secondary PUCCH group. When some embodiments of the present invention described below are applied to the primary PUCCH group, the terms "secondary cell", "secondary cells", "serving cell", and "serving cells" described below may refer to the secondary cell, secondary cells, serving cell, and serving cells belonging to the primary PUCCH group, respectively. When some embodiments of the present invention described below are applied to the secondary PUCCH group, the terms "secondary cell", "secondary cells" (not including PScell), "serving cell", and "serving cells" described below may refer to the secondary cell, secondary cells, serving cell, and serving cells belonging to the secondary PUCCH group, respectively. Hereinafter, the term "primary cell" may refer to the PCell of the primary PUCCH group when some embodiments of the present invention are applied to the primary PUCCH group, and may refer to the PUCCH-SCell of the secondary PUCCH group when some embodiments of the present invention are applied to the secondary PUCCH group.

[0253] In this specification, carriers, component carriers may refer to the cells that contain these carriers, i.e. carrier change may refer to a change from one cell to another, or between carriers within one cell.

[0254] UE Position:

[0255] FIG. 16 illustrates an example of a HARQ-ACK transmission flow according to some implementations of this disclosure.

[0256] The UE connects to the BS to perform cell setup, and receives information about component carriers that the UE can use through the cell setup. The BS transmits a MAC control element (CE) message to the UE to activate or deactivate each carrier. When the BS schedules the UE to receive a PDSCH and transmit a PUCCH for a HARQ-ACK response thereto, the UE dynamically selects a carrier on which the PUCCH for the HARQ-ACK response is transmitted using some implementations of this specification, and determines a PUCCH resource to be used on the corresponding carrier using some implementations of this specification.

[0257] In some implementations, for example, a UE receives scheduling information for PDSCH reception and scheduling information for PUCCH transmission for a HARQ-ACK response thereto (S1601). If the UE supports HARQ-ACK deferral and PUCCH cell change, the UE determines a PUCCH cell and PUCCH slot in which PUCCH transmission for the scheduled PDSCH reception will be performed based on the HARQ-ACK deferral and / or PUCCH cell change according to some implementations of this specification (S1603). The UE transmits a PUCCH including HARQ-ACK information for the scheduled PDSCH reception in the determined PUCCH slot on the determined PUCCH cell (S1605).

[0258] The following is an example of UE operation according to some implementations of this specification.

[0259] 1) When connecting to a BS, the UE receives an RRC configuration including component carrier information (eg, ServingCellConfigCommon) from the BS via RRC signaling.

[0260] 2) The UE receives the SPS PDSCH configuration and the RRC configuration for HARQ-ACK deferral for the SPS PDSCH from the BS via RRC signaling.

[0261] 3) The BS sends a MAC CE message to the UE to activate or deactivate each carrier configured for the UE.

[0262] 4) The BS schedules the UE for PDSCH reception, SPS PDSCH release reception, and PUCCH transmission for HARQ-ACK response to these.

[0263] 5) The UE determines whether to change the carrier on which the PUCCH for the HARQ-ACK response is transmitted and / or change the indicated / configured HARQ-ACK transmission time using some implementation of this specification.

[0264] 6) The UE determines the PUCCH resource to be used for the changed / determined carrier / HARQ-ACK transmission time point using some implementation of this specification.

[0265] In some implementations of this specification, a downlink symbol refers to a symbol contained in any one of the following:

[0266] - a set symbols of the slot to be indicated as downlink by tdd-UL-DL-ConfigurationCommon or tdd-UL-DL-ConfigurationDedicated;

[0267] - a set of symbols of a slot indicated to a UE by pdcch-ConfigSIB1 in master information block (MIB) for a CORESET for Type0-PDCCH CSS set;

[0268] - a set of symbols of a slot that are indicated to the UE for reception of SS / PBCH blocks in any of multiple serving cells by ssb-PositionsInBurst in SystemInformationBlockType1 or by ssb-PositionsInBurst in ServingCellConfigCommon;

[0269] - the set of symbols of the slot which a DCI format 2_0 with an SFI-index field value indicates as downlink.

[0270] In some implementations of this specification, an uplink symbol refers to a symbol that is included in at least one of the following:

[0271] - a set symbols of the slot to be indicated as uplink by tdd-UL-DL-ConfigurationCommon or tdd-UL-DL-ConfigurationDedicated;

[0272] A set of symbols of a slot corresponding to a valid PRACH period and N symbols before the valid PRACH period gap symbols (a set of symbols of a slot corresponding to a valid PRACH occasion and Ngap symbols before the valid PRACH occasion);

[0273] - a set of symbols of the slot which a DCI format 2_0 with an SFI-index field value indicats as uplink.

[0274] The UE operation in accordance with some implementations of this specification described below will be primarily described from the perspective of transmitting UCI on the PUCCH, particularly HARQ-ACK responses to SPS PDSCHs, on the PUCCH, however, implementations of this specification also apply to PUSCH and PUCCH transmissions conveying other UCI, as well as HARQ-ACK responses to PDSCHs scheduled via DCI.

[0275] In some implementations of this specification, the PUCCH carrier change refers to the operation of the UE arbitrarily changing the PUCCH carrier according to a predefined rule to transmit the PUCCH, as described above. The predefined rule may be as follows:

[0276] > If the PUCCH radio resource is determined based on the PRI included in the DCI, and the DCI includes a PUCCH carrier indication, the UE performs a PUCCH carrier change according to the PUCCH carrier indication.

[0277] The PUCCH carrier change pattern is configured in the UE via higher layer signaling (e.g., RRC signaling) from the BS.

[0278] >> A PUCCH carrier change pattern refers to information in which a list containing one or more available UL CCs is arranged in sequence according to a certain time unit (e.g., a couple of slots) over a certain time period (e.g., dozens of slots, one frame, or 10 ms).

[0279] >> To express that a list of available UL CCs occupies a certain time unit, we define a time length T L This time length T L means the time that the list occupies. In this case, the period of the PUCCH carrier change pattern is the time length T L For example, if there is a UL CC list L1={C1, C2, C3}, and time information T L For example, L1={{C1, C2, C3}, T L} is provided. In this case, time T L At least one of C1, C2, and C3 is used during the pattern. Such lists are ordered. For example, if they are ordered as {L1, L2, L3, ..., LN}, the sum of the time lengths T for each Ln represents the length of the entire pattern.

[0280] >> In some implementations, one or more patterns contain information indicating that no PUCCH carrier change is to be performed during a particular time period. This information may be expressed as a UL CC list that includes another RRC parameter (e.g., noPUCCHCarrierSwithcing). The UE may not perform a PUCCH carrier change during a period that includes such information.

[0281] >> The time unit or slot length (i.e., the time length per slot) is determined by the UL subcarrier spacing setting configured in the cell. For example, at least one of the following is possible:

[0282] >>> A separate UL reference SCS for the PUCCH carrier change pattern is set, and the time unit is determined by the SCS value.

[0283] >>> Determined by the maximum or minimum SCS of the UL BWPs configured in the UE.

[0284] >>> Determined by the maximum or minimum SCS configurable in the cell. For example, determined by the smallest or largest SCS configuration u provided in the scs-SpecificCarrierList of FrequencyInfoUL or FrequencyInfoUL-SIB.

[0285] When one frame is 10 ms long, the slot length for each SCS setting u is determined according to Table 1.

[0286] <Implementation A1> Deferring first within a PUCCH carrier, carrier switching second

[0287] When a UE receives an SPS PDSCH configured / instructed by a BS and attempts to transmit a HARQ-ACK response thereto, if the HARQ-ACK transmission cannot be transmitted overlapped in time with one or more downlink symbols based on the instructed or configured PUCCH resource and PDSCH-to-HARQ-ACK timing, the UE first performs a HARQ-ACK postponement procedure in an initial slot, determines a new target slot in which the HARQ-ACK response is to be transmitted, and transmits the HARQ-ACK response in the corresponding slot.

[0288] If the UE is able to transmit a HARQ-ACK response as a result of the HARQ-ACK postponement process, i.e., due to the HARQ-ACK postponement, at a location farther away from the end of associated PDSCH reception or the start of indicated PUCCH transmission in the initial slot than a time interval T (e.g., a maximum deferral limit) (e.g., when the PDSCH reception end time T_pdsch or the PUCCH transmission start time T_pucch is taken as the PDSCH reception end time, the HARQ-ACK response can be transmitted at a time later in time than T_pdsch+T or T_pucch+T), or if an explicit latency budget (e.g., a packet latency budget) is given for a service associated with the HARQ-ACK response transmitted by the UE and it is determined that it is not easy for the determined target slot to meet the latency budget (e.g., a packet latency budget), or if the HARQ-ACK postponement process is not successful for other reasons, the UE attempts to change the PUCCH carrier and transmits PUCCH in the initial slot of another CC.

[0289] The time interval T is a value that is predefined or determined by L1 signaling and / or higher layer signaling of the BS.

[0290] Implementation A1 minimizes the UE's PUCCH carrier change operation, thereby making maximum use of channel information for a corresponding CC that the UE acquires and holds from one CC.

[0291] <Realization A2> Carrier switching first, deferring second

[0292] When the UE receives the SPS PDSCH configured / instructed from the BS and attempts to transmit a HARQ-ACK response to the SPS PDSCH, if the HARQ-ACK transmission cannot be transmitted overlapped in time with one or more downlink symbols, as determined based on the instructed or configured PUCCH resource and PDSCH-to-HARQ-ACK timing, the UE first attempts to change the PUCCH carrier in the initial slot and transmits the PUCCH. If the PUCCH transmission cannot be transmitted in the initial slot due to the change in the PUCCH carrier, the UE may perform a HARQ-ACK postponement procedure.

[0293] For example, the UE attempts to transmit the HARQ-ACK PUCCH in the initial slot, preferably by changing the PUCCH carrier, and only if the PUCCH cannot be transmitted in the initial slot even after changing the PUCCH carrier (e.g., there is no CC in the initial slot with sufficient UL symbols for the PUCCH transmission), the UE further postpones the HARQ-ACK, determines a new target slot in which the HARQ-ACK will be transmitted, and transmits the HARQ-ACK response in that slot.

[0294] When the UE further performs HARQ-ACK postponement, the UE may perform HARQ-ACK postponement using some implementations of this specification, thereby allowing the UE to perform HARQ-ACK postponement taking into account multiple component carriers and minimize the round-trip time (RTT) required for receiving the PDSCH.

[0295] Alternatively, to simplify the operation of the UE, when the UE receives a configured / instructed SPS PDSCH from the BS and attempts to transmit a HARQ-ACK response thereto, if the HARQ-ACK transmission determined based on the instructed or configured PUCCH resource and PDSCH-to-HARQ-ACK timing cannot be transmitted overlapped in time with one or more downlink symbols, the UE may try to change the PUCCH carrier in the initial slot to transmit the PUCCH, and may not perform the HARQ-ACK postponement procedure even if the PUCCH transmission in the initial slot is not possible due to the PUCCH carrier change. In other words, the UE does not perform the HARQ-ACK postponement procedure once it has changed the PUCCH carrier.

[0296] As another example, when a PUCCH carrier change is performed according to a PUCCH carrier change pattern, whether or not to allow a PUCCH carrier change at each time is determined by the PUCCH carrier pattern. The UE does not change the PUCCH carrier at a position where an initial CC is specified on the PUCCH carrier pattern, but changes the PUCCH carrier at a position where a carrier to be changed is specified. In this case, the UE changes the PUCCH carrier when a PUCCH carrier change is permitted, and performs a HARQ-ACK postponement process in a period when a PUCCH carrier change is not permitted.

[0297] <Realization A2-1> Deferring after carrier switching

[0298] In the case of implementation A2, when a UE receives an SPS PDSCH configured / instructed from a BS and attempts to transmit a HARQ-ACK response thereto, if the HARQ-ACK transmission determined based on the instructed or configured PUCCH resource and PDSCH-to-HARQ-ACK timing cannot be transmitted overlapping in time with one or more downlink symbols, the UE first attempts to change the PUCCH carrier in the initial slot and transmits the PUCCH.

[0299] If the UE is explicitly configured with a target carrier for carrier change used in an uplink slot in which PUCCH is scheduled, the UE will perform a HARQ-ACK postponement procedure if PUCCH transmission is not possible in the initial slot after PUCCH carrier change. In this case, the following methods may be used:

[0300] Method A2_1: The UE performs a carrier change on the target carrier configured for use in the initial slot, and postpones PUCCH transmission to a target slot where PUCCH transmission is possible on the target carrier. If the uplink carrier configured for use in the target slot is different from the target carrier, the UE performs another PUCCH carrier change on the target carrier.

[0301] * Method A2_2: The UE performs a HARQ-ACK postponement process on the original carrier, postpones PUCCH transmission to a target slot where PUCCH can be transmitted on the original carrier, and performs carrier change to the target carrier set to be used in the target slot and transmits PUCCH.

[0302] * Method A2_3: The UE considers the uplink carrier set to be used in each UL slot in the process of performing the HARQ-ACK postponement process as in implementations A3 / B3. For example, in the process of searching for the first UL slot in which the postponed PUCCH transmission can be performed, the UE considers whether the target uplink carrier of the corresponding slot (e.g., the uplink slot in which the PUCCH carrier to be used is set) can transmit the PUCCH. If the PUCCH transmission is possible, the UE postpones the PUCCH transmission to a slot in which the PUCCH transmission is possible among the slots of the corresponding target uplink carrier.

[0303] <Implementation A3> HARQ-ACK deferral with PUCCH carrier switching

[0304] FIG. 17 illustrates an example of cells and slots in which a HARQ-ACK response may be transmitted according to some implementations of the present disclosure.

[0305] When a UE configured with multiple component carriers (CCs) performs a HARQ-ACK postponement operation, in other words, when the UE transmits a HARQ-ACK response transmission in an initial slot on an initial CC instructed / configured by a BS in another target slot, the UE determines a target slot and a target CC in which the HARQ-ACK response is to be transmitted, taking into account the configured CC. For example, when a UE configured with multiple CCs receives a (SPS) PDSCH configured / instructed by a BS and is about to transmit a HARQ-ACK response to the (SPS) PDSCH reception, the UE determines a target slot and a target CC in which the corresponding HARQ-ACK transmission is actually performed, which are determined based on the instructed or configured PUCCH resource and PDSCH-to-HARQ-ACK timing, taking into account the configured CC and HARQ-ACK postponement. In some implementations of this specification, the UE determines a target slot in which the PUCCH transmission is to be performed and a target CC in which the PUCCH transmission is to be performed, based on at least one of the following:

[0306] * Method A3_1: Among the slots within a predetermined time interval from the initial slot, a component carrier having sufficient consecutive available symbols (e.g., consecutive uplink or flexible symbols) to transmit the PUCCH resource of the deferred HARQ-ACK response is selected as the target PUCCH carrier. In this case, the slot of each component carrier having consecutive available symbols becomes the target slot of each component carrier. This predetermined time interval is a value indicated or set by the BS, or a maximum deferral limit derived by the UE based on it.

[0307] * Method A3_2: When the target slot of each component carrier is determined, the component carrier with the smallest interval between this target slot and the initial slot is selected as the target CC.

[0308] * Method A3_3: When the target slot of each component carrier is determined, the component carrier with the earliest start symbol of the PUCCH resource in which the delayed HARQ-ACK response is transmitted from the target slot of each component carrier is selected as the target CC.

[0309] * Method A3_4: An activated component carrier is selected as the target CC.

[0310] * Method A3_5: A component carrier having the same subcarrier spacing as the initial CC is selected as the target CC.

[0311] * Method A3_6: A component carrier having a subcarrier spacing equal to or larger than the initial CC is selected as the target CC.

[0312] * Method A3_7: If a component carrier capable of transmitting the same level of priority as a deferred HARQ-ACK response in the initial CC, i.e., the deferred HARQ-ACK response in the initial CC has a higher priority, a component carrier with PUCCH resources configured for higher priority is selected as the target CC.

[0313] * Method A3_8: If two or more component carriers are selected according to all the considered conditions, the component carrier having the lower cell index among them is selected as the target CC.

[0314] Alternatively, in some implementations of this specification, the same method (described above) for the UE to determine the PUCCH carrier to be changed by the PUCCH carrier change is used as the method for determining the target CC. For example, the PUCCH cell for a slot is determined according to a predetermined or defined rule. In this case, , multiple Considering the number of CCs TeH To perform the ARQ-ACK postponement operation, UE is Slot n, slot n+1, ..., slot n+k Each of Change PUCCH carrier in That Assuming that PUCCH is transmitted can be Earliest Slot In PUCCH carrier change By applying , For a given PUCCH in initial slot n (i.e., a given PUCCH for initial slot n), Sending a deferred HARQ-ACK response can In other words, to support simultaneous configuration of HARQ-ACK deferral and PUCCH cell change, the UE determines a next PUCCH slot on the determined PUCCH cell according to a predefined rule for PUCCH cell change, and determines whether the next PUCCH slot on the PUCCH cell for transmission is a target PUCCH slot based on the rule for HARQ-ACK deferral, where the next PUCCH slot is a slot in which the HARQ-ACK response is to be transmitted. Kedji where k is incremented on the initial cell.

[0315] Referring to FIG. 17, assuming that the initial CC and the initial slot for which the HARQ-ACK response transmission is scheduled are cell A and slot n, respectively, the UE determines that cell B is the PUCCH transmission cell for slot n based on a predefined rule for PUCCH cell change. The UE determines whether the HARQ-ACK response can be transmitted in the earliest slot m overlapping with slot n among the slots on cell B. For example, the UE determines a PUCCH resource for a UCI including the corresponding HARQ-ACK response in the earliest slot m overlapping with slot n among the slots on cell B, and determines whether the HARQ-ACK response can be transmitted in slot m on cell B based on whether the PUCCH resource includes a downlink symbol. The UE determines to postpone the transmission of the HARQ-ACK response when the ARQ-ACK response cannot be transmitted in slot m on cell B, for example, when the PUCCH resource in slot m on cell B for the HARQ-ACK response includes a downlink symbol. To determine the target slot for which the transmission of the HARQ-ACK response is postponed, the UE determines the PUCCH cell in slot n+1 on cell A where the transmission of the HARQ-ACK response was originally scheduled, and determines whether slot m+2 of cell B, which is the PUCCH cell in slot n+1, mapped to slot n+1, is the target slot for the transmission of the postponed HARQ-ACK response. If the postponed HARQ-ACK response can be transmitted in slot m+2 of cell B, the UE transmits UCI including the postponed HARQ-ACK response in the PUCCH resource in slot m+2 of cell B. If the postponed HARQ-ACK response cannot be transmitted in slot m+2 of cell B, the UE determines whether the postponed HARQ-ACK response can be transmitted in slot n+2 on cell A, which is the PUCCH cell for slot n+2, and determines whether slot n+2 on cell A is the target slot.

[0316] When considering the UL slots of each UL component carrier, the UL slots are counted taking into consideration the slot length (i.e., the time length of the slot) set for each HARQ-ACK codebook for each priority. In this case, in order to simplify the operation, the UL slot applied in the target CC when using the corresponding priority is considered as the UL slot for the target CC, taking into consideration the priority indicated / set for the source PUCCH where the carrier change is performed. For example, in a situation where slot lengths X and Y are used respectively for priorities 0 and 1 in cell A and slot lengths Y and Z are used respectively for priorities 0 and 1 in cell B, if the UCI of the PUCCH transmission indicated as priority 1 of cell A is transmitted to cell B by carrier change, the UCI of the PUCCH transmission is transmitted in the PUCCH of cell B based on slot length Z. In some implementations of this specification, the target CC is limited to CCs set with the same priority for this operation.

[0317] Since the effects obtained from HARQ-ACK postponement and PUCCH cell change are similar, the UE and BS can achieve to some extent the purpose of transmitting the PUCCH that could not be transmitted due to overlapping with downlink symbols in the originally scheduled slot on the initial cell even if only one of HARQ-ACK postponement and PUCCH cell change is performed at the time when HARQ-ACK postponement and PUCCH cell change are requested. However, when the UE and BS consider both HARQ-ACK postponement and PUCCH cell change according to implementation A3, there is an advantage that a shorter delay time can be secured in relation to PUCCH transmission compared to performing only one of them or separately considering HARQ-ACK postponement and PUCCH cell change.

[0318] <Implementation A4> Maximum HARQ-ACK deferral considering PUCCH carrier switching

[0319] When a UE configured with multiple component carriers (CCs) performs HARQ-ACK deferral, in other words, when the UE transmits a HARQ-ACK response transmission in an initial slot on an initial CC instructed / configured by the BS in other target slots, the UE determines the maximum HARQ-ACK deferral range max_defer taking into account the configured CC. The UE performs HARQ-ACK deferral only within the max_defer range. As an example, to determine the max_defer value, the UE considers at least one of the following:

[0320] > If the UE considers the set of configured PDSCH-to-HARQ_Feedback-Timing K1 to determine max_defer, e.g., if it considers the configured dlDataToUL-ACK, dl-DataToUL-ACK-r16, or dl-DataToUL-ACKForDCIFormat1_2,

[0321] >> Consider only the UL component carriers used when no PUCCH carrier change is performed, e.g., the K1 set configured for the primary cell.

[0322] >> Consider the K1 set of all candidate cells subject to the configured PUCCH carrier change.

[0323] >> At the time of HARQ-ACK postponement, only the K1 set configured for the available UL component carriers configured for the PUCCH carrier change pattern is considered.

[0324] > If the UE uses max_defer included in each SPS PDSCH configuration to determine max_defer, the corresponding value shall be used without modification. For reference, the parameter max_defer in the SPS PDSCH configuration indicates the maximum number of slots or subslots in which the transmission of the SPS HARQ-ACK in the slot or subslot can be postponed.

[0325] When the UE considers the set of configured PDSCH-to-HARQ_feedback timing K1 to determine max_defer, the UE determines, for example, the maximum K1 value in the configured K1 set as the maximum range of HARQ-ACK postponement max_defer. That is, even if HARQ-ACK postponement is performed, the HARQ-ACK postponement operation is performed so that the position difference between the postponed HARQ-ACK PUCCH and the corresponding PDSCH reception slot is limited to max_defer.

[0326] In order to determine the maximum K1 value or to apply the determined max_defer to UL component carriers with different actual slot lengths (e.g., different subcarrier spacings), the max_defer time length needs to be determined. That is, when PUCCH carrier change is used, the time point of PUCCH transmission postponed from the PDSCH reception time point is limited by the actually calculated max_defer time length. For this purpose, at least one of the following is considered:

[0327] > The effective slot offset length applied with the subcarrier spacing of the UL component carrier used when the PUCCH carrier is not changed is used as the time length of max_defer. That is, even if the UE postpones HARQ-ACK due to a PUCCH carrier change, the HARQ-ACK postponement due to the PUCCH carrier change does not exceed the maximum HARQ-ACK postponement range when the PUCCH carrier is not changed.

[0328] > Determined by the UL reference SCS or UL reference cell used for the PUCCH carrier change pattern. The PUCCH carrier change pattern is predefined / configured based on the UL reference SCS or UL cell, the BS configures a max_defer value for each SPS configuration based on the UL reference SCS or UL reference cell, and the UE interprets the configured max_defer value based on the UL reference SCS or UL reference cell to determine the (maximum) slot range in which the HARQ-ACK can be deferred. The UL reference SCS or UL reference cell is configured or defined to be commonly used for all SPS configurations (e.g., the primary cell or Pcell is predefined as the UL reference cell). Alternatively, the UL reference SCS or UL reference cell may be configured for each SPS configuration.

[0329] The time length of max_defer is determined by the SCS with the maximum or minimum subcarrier spacing among the UL BWPs configured for all candidate cells that are targets of the PUCCH carrier change.

[0330] The duration of max_defer is determined by the maximum or minimum subcarrier spacing that can be set in the cell. For example, the duration of max_defer is determined by the maximum or minimum SCS configuration u provided in the scs-SpecificCarrierList of the RRC configuration FrequencyInfoUL or FrequencyInfoUL-SIB.

[0331] > Depending on the given subcarrier spacing, max_defer * (number of OFDM symbols per slot) * (symbol length for a given SCS) or max_defer * (10 ms) / (number of slots per frame for a given SCS) is used as the actual max_defer duration.

[0332] When max_defer is applied, assuming a specific cell or a specific SCS, the boundary of the maximum deferral range determined as max_defer may overlap with the postponed PUCCH transmission. For example, in a general single carrier operation, the boundary of the maximum deferral range determined as max_defer coincides with the slot boundary, so there is no difficulty in checking the validity of the deferral operation. In a general single carrier operation, the UE determines that the PUCCH is valid if it is postponed within the boundary of the deferral range, and invalid if it is postponed outside the boundary. However, in a HARQ-ACK postponement process considering a PUCCH carrier change, the boundary of the determined maximum deferral range may not coincide with the slot boundary of the uplink carrier on which the PUCCH is transmitted.

[0333] When the boundary of the maximum deferral range does not coincide with the slot boundary of the uplink carrier on which the PUCCH is transmitted, the boundary of the deferral range may pass within the PUCCH resource. In this case, it is difficult to determine whether the PUCCH should be dropped beyond the boundary of the deferral range. In some implementations of this specification, the following can be considered to determine the validity of the dropping and deferral operation of the PUCCH in such a case.

[0334] Method A4_1: The boundary of the deferral range is redefined based on the slot of the PUCCH carrier. To this end, at least one of the following methods is possible:

[0335] ** Method A4_1-1: The UE determines that one or more slots within the range for which deferral operation is possible based on the reference cell or reference SCS used to determine the boundary of the deferral range are within the range for which deferral operation is possible, and that a slot of a PUCCH carrier that overlaps in time with the slot is within the range for which deferral operation is possible.

[0336] ** Method A4_1-2: The UE determines that a slot of a PUCCH carrier that overlaps in time with more than half of the slots within the range for which deferral operation is possible (i.e., overlaps with more than half of the symbols that make up the slot) based on the reference cell or reference SCS used to determine the boundary of the deferral range is within the range for which deferral operation is possible.

[0337] ** Method A4_1-2: The UE determines that the slots of the PUCCH carrier that are completely included in the range where the deferral operation is possible based on the reference cell or reference SCS used to determine the boundary of the deferral range are within the range where the deferral operation is possible. In other words, the UE assumes that only slots that end before the boundary of the deferral range are within the range where the deferral operation is possible.

[0338] Method A4_2: Using the PUCCH resource as a reference, compare the PUCCH resource with the boundary of the deferral range to judge the validity of the deferral operation. To this end, at least one of the following may be considered:

[0339] ** Method A4_2-1: The UE determines that the deferral operation is valid if one or more symbols of the PUCCH resource are included in the range where the deferral operation is possible. In other words, the UE determines that the deferral operation is invalid only if the starting symbol of the PUCCH resource is later than the boundary of the deferral range.

[0340] ** Method A4_2-1: The UE determines that the deferral operation is valid if more than half of the symbols of the PUCCH resource are included in the range where the deferral operation is possible.

[0341] ** Method A4_2-2: The UE determines that the deferral operation is valid only if all symbols of the PUCCH resource are within the range in which the deferral operation is possible. In other words, if the last symbol of the PUCCH resource is later than the boundary of the deferral range, the UE determines that the deferral operation is invalid.

[0342] <Implementation A5> Reference subcarrier spacing for PUCCH cell / carrier switching

[0343] In some implementations of this specification, the PUCCH cell / carrier change means that the UE arbitrarily changes the PUCCH cell / carrier according to a predefined rule to transmit the PUCCH, as described above. The predefined rule may be as follows:

[0344] * The PUCCH radio resource is determined by the PRI included in the DCI, and if the DCI includes a PUCCH carrier indication, the PUCCH carrier is changed according to the PUCCH carrier indication.

[0345] * A PUCCH carrier change pattern is configured in the UE via higher layer signaling from the BS. The PUCCH carrier change pattern is information that lists cells to be used in a certain time unit (e.g., slots for a given SCS configuration) in a certain time period (e.g., dozens of slots, one frame, or 10 ms). If the UE performs a PUCCH carrier / cell change between two cells, a primary cell and a SCell configured as a target for the PUCCH carrier / cell change, the PUCCH carrier change pattern is information that lists whether the primary cell or the configured SCell is used in each time unit of a certain time period. The length of this time unit or slot is determined by the UL subcarrier spacing configuration configured in the cell. As an example, the reference SCS configuration u_ref according to referenceSubcarrierSpacing provided in tdd-UL-DL-ConfigurationCommon is used to determine the time unit or slot length.

[0346] When one frame is 10 ms long, the slot length according to each SCS setting u is determined according to Table 1.

[0347] As mentioned above, the reference SCS configuration provided to the UE by tdd-UL-DL-ConfigurationCommon is used to determine the slot length of the PUCCH cell / carrier change pattern. However, this parameter is not essential for UE operation, so the BS does not have to configure this parameter for network configuration and operation. In some implementations of this specification, in this case, i.e., if the UE is not configured with higher layer parameters required for interpreting the PUCCH cell / carrier change pattern, the UE interprets the PUCCH cell / carrier change pattern using at least one of the following:

[0348] * Method A5_1: In order to prevent such a case, the reference SCS setting in tdd-UL-DL-ConfigurationCommon is defined as a prerequisite for PUCCH cell / carrier change. In other words, it is defined that PUCCH cell / carrier change is performed only when the reference SCS parameter in tdd-UL-DL-ConfigurationCommon is configured. As an example, if the reference SCS setting in tdd-UL-DL-ConfigurationCommon is not provided, the UE may not perform the PUCCH cell / carrier change operation. Or, as another example, the tdd-UL-DL-ConfigurationCommon parameter set is defined as a prerequisite element for the UE's PUCCH cell / carrier change capability. In other words, it is defined that PUCCH cell / carrier change is performed when the information element (IE) tdd-UL-DL-ConfigurationCommon is configured in the UE. This ensures that when the BS configures the UE for PUCCH cell / carrier change behavior, the tdd-UL-DL-ConfigurationCommon parameter set is always given.

[0349] * Method A5_2: In case the tdd-UL-DL-ConfigurationCommon parameter set is not given, a separate UL reference SCS for the PUCCH carrier modification pattern is configured, and the slot length of the PUCCH cell / carrier modification pattern is determined by the corresponding SCS value only if the tdd-UL-DL-ConfigurationCommon parameter set is not given.

[0350] * Method A5_3: If the tdd-UL-DL-ConfigurationCommon parameter set is not provided, the slot length of the PUCCH cell / carrier change pattern is determined by the SCS with the maximum or minimum subcarrier spacing among all UL BWPs configured in the UE (in the primary cell). Or, for the simplification of the UE operation, the slot length of the PUCCH cell / carrier change pattern is always determined by the SCS with the maximum or minimum subcarrier spacing among all UL BWPs configured in the UE (in the primary cell), regardless of whether the tdd-UL-DL-ConfigurationCommon parameter set is provided in the UE.

[0351] * Method A5_4: If the tdd-UL-DL-ConfigurationCommon parameter set is not given, the slot length of the PUCCH carrier change pattern is determined by the maximum or minimum subcarrier spacing configurable in the primary cell. As an example, the slot length of the PUCCH cell / carrier change pattern is determined by the smallest or largest SCS configuration u provided in the scs-SpecificCarrierList of FrequencyInfoUL or FrequencyInfoUL-SIB. Alternatively, for the simplification of UE operation, the slot length of the PUCCH carrier change pattern is always determined by the maximum or minimum subcarrier spacing configurable in the primary cell, regardless of whether the tdd-UL-DL-ConfigurationCommon parameter set is given or not.

[0352] * Method A5_5: If the tdd-UL-DL-ConfigurationCommon parameter set is not provided, the slot length of the PUCCH cell / carrier change pattern is determined using a predefined SCS value (e.g., u=0; 15 kHz). Alternatively, to simplify UE operation, the slot length of the PUCCH cell / carrier change pattern is always determined using a predefined SCS value (e.g., u=0; 15 kHz), regardless of whether the tdd-UL-DL-ConfigurationCommon parameter set is provided or not.

[0353] * Method A5_6: If the tdd-UL-DL-ConfigurationCommon parameter set is not provided, the slot length of the PUCCH cell / carrier change pattern is determined by the SCS of the BWP with the lowest id among all UL BWPs configured in the UE (for the primary cell). Alternatively, for the simplification of the UE operation, the slot length of the PUCCH cell / carrier change pattern is always determined by the SCS of the BWP with the lowest id among all UL BWPs configured in the UE (for the primary cell), regardless of whether the tdd-UL-DL-ConfigurationCommon parameter set is provided or not.

[0354] * Method A5_7: If the tdd-UL-DL-ConfigurationCommon parameter set is not provided, the slot length of the PUCCH cell / carrier change pattern is determined by the SCS of the initial uplink BWP (e.g., the BWP provided by the RRC parameter initialUplinkBWP) configured in the UE (for the primary cell). Alternatively, for the sake of simplicity of UE operation, the slot length of the PUCCH cell / carrier change pattern is always determined by the SCS of the initial uplink BWP (e.g., the BWP provided by the RRC parameter initialUplinkBWP) configured in the UE (for the primary cell), regardless of whether the tdd-UL-DL-ConfigurationCommon parameter set is provided or not.

[0355] * Method A5_8: If the tdd-UL-DL-ConfigurationCommon parameter set is not provided, the slot length of the PUCCH cell / carrier change pattern is determined by the SCS of the first active uplink BWP (e.g., the BWP provided by the RRC parameter firstActiveUplinkBWP-Id) configured in the UE (in the primary cell). Alternatively, for simplification of UE operation, the slot length of the PUCCH cell / carrier change pattern is always determined by the SCS of the first active BWP (e.g., the BWP provided by the RRC parameter firstActiveUplinkBWP-Id) configured in the UE (in the primary cell), regardless of whether the tdd-UL-DL-ConfigurationCommon parameter set is provided.

[0356] The UE and the BS can use multiple of the above methods simultaneously and in a complementary manner. For example, the UE and the BS can use method A5_1 and method A5_2 together, and use method A5_1 when the tdd-UL-DL-ConfigurationCommon parameter set is provided, and use method A5_2 when the tdd-UL-DL-ConfigurationCommon parameter set is not provided.

[0357] BS position:

[0358] FIG. 18 illustrates an example of a HARQ-ACK receiving flow according to some implementations of this disclosure.

[0359] The above-mentioned implementation of this specification will be described again from the perspective of a BS. The BS provides a cell configuration to a UE connected to the BS, and transmits information about component carriers that the UE can use according to the cell configuration. The BS transmits a MAC control element (CE) message to the UE to activate or deactivate each carrier. When the BS schedules the UE to receive a PDSCH and transmit a PUCCH for a HARQ-ACK response thereto, the UE dynamically selects a carrier on which the PUCCH for the HARQ-ACK response is transmitted using some implementations of this specification, and the BS receives uplink control information (UCI) according to a PUCCH resource used on the corresponding carrier using some implementations of this specification.

[0360] In some implementations, for example, the BS transmits to the UE scheduling information regarding PDSCH transmission and scheduling information regarding PUCCH reception for a HARQ-ACK response thereto (S1801). If the UE supports HARQ-ACK deferral and PUCCH cell change, for example, if the BS configures the UE with HARQ-ACK deferral and PUCCH cell change, the BS determines a PUCCH cell and PUCCH slot in which PUCCH reception for the scheduled PDSCH transmission is to be performed based on the HARQ-ACK deferral and / or PUCCH cell change according to some implementations of this specification (S1803). The BS performs PUCCH reception including HARQ-ACK information for the scheduled PDSCH transmission in the determined PUCCH slot on the determined PUCCH cell (S1805).

[0361] Below is an example of BS operation according to some implementations of this specification.

[0362] 1) When the UE connects to the BS, the BS sends an RRC configuration including component carrier information (e.g., ServingCellConfigCommon) to the UE via RRC signaling.

[0363] 2) The BS sends the SPS PDSCH configuration and the RRC configuration for HARQ-ACK deferral for the SPS PDSCH to the UE via RRC signaling.

[0364] 3) The BS sends a MAC CE message to the UE to activate or deactivate each carrier configured for the UE.

[0365] 4) The BS schedules the UE for PDSCH reception, SPS PDSCH release reception, and PUCCH transmission for HARQ-ACK response to these.

[0366] 5) The BS decides whether to change the carrier on which the PUCCH for the HARQ-ACK response is transmitted and / or change the indicated / configured HARQ-ACK transmission time using some implementation of this specification.

[0367] 6) The BS determines the PUCCH resources to be used at the changed / determined carrier / HARQ-ACK transmission time using some implementation of this specification.

[0368] In some implementations of this specification, a downlink symbol refers to a symbol that is included in at least one of the following:

[0369] - a set symbols of the slot to be indicated as downlink by tdd-UL-DL-ConfigurationCommon or tdd-UL-DL-ConfigurationDedicated;

[0370] - a set of symbols of a slot indicated to a UE by pdcch-ConfigSIB1 in master information block (MIB) for a CORESET for Type0-PDCCH CSS set;

[0371] - a set of symbols of a slot that are indicated to the UE for reception of SS / PBCH blocks in any of multiple serving cells by ssb-PositionsInBurst in SystemInformationBlockType1 or by ssb-PositionsInBurst in ServingCellConfigCommon;

[0372] - the set of symbols of the slot which a DCI format 2_0 with an SFI-index field value indicates as downlink.

[0373] In some implementations of this specification, an uplink symbol refers to a symbol that is included in at least one of the following:

[0374] - a set symbols of the slot to be indicated as uplink by tdd-UL-DL-ConfigurationCommon or tdd-UL-DL-ConfigurationDedicated;

[0375] - a set of symbols of a slot corresponding to a valid PRACH period and N symbols before this valid PRACH period gap symbols (a set of symbols of a slot corresponding to a valid PRACH occasion and Ngap symbols before the valid PRACH occasion);

[0376] - a set of symbols of the slot which a DCI format 2_0 with an SFI-index field value indicats as uplink.

[0377] The BS operation in some implementations of this specification described below will be primarily described from the perspective of receiving UCI on a PUCCH, particularly a HARQ-ACK response to an SPS PDSCH, but the implementations of this specification can also be applied to PUSCH reception and PUCCH reception conveying other UCI, as well as HARQ-ACK responses to PDSCHs scheduled by DCI.

[0378] In some implementations of this specification, the PUCCH carrier change refers to the operation of the BS arbitrarily changing the PUCCH carrier according to a predefined rule to receive the PUCCH, as described above. The predefined rule may be as follows:

[0379] > If the PUCCH radio resource is determined based on the PRI included in the DCI, and the DCI includes a PUCCH carrier indication, the BS performs a PUCCH carrier change for the UE according to the PUCCH carrier indication.

[0380] The PUCCH carrier change pattern is configured in the UE via higher layer signaling (e.g., RRC signaling) from the BS.

[0381] >> A PUCCH carrier change pattern refers to information in which a list containing one or more available UL CCs is arranged in sequence according to a certain time unit (e.g., a couple of slots) over a certain time period (e.g., dozens of slots, one frame, or 10 ms).

[0382] >> To express that a list of available UL CCs occupies a certain time unit, we define a time length T L This time length T L means the time that the list occupies. In this case, the period of the PUCCH carrier change pattern is the time length T L For example, if there is a UL CC list L1={C1, C2, C3}, and this list L1 contains time information T L For example, L1={{C1, C2, C3}, T L} is provided. In this case, time T L At least one of C1, C2, and C3 is used during this time. This list is ordered. For example, if it is ordered as {L1, L2, L3, ..., LN}, the sum of the time lengths T for each Ln represents the length of the entire pattern.

[0383] >> In some implementations, one or more patterns may include information indicating that no PUCCH carrier change is performed in a given time period. This information is expressed as a list of UL CCs including a separate RRC parameter (e.g., noPUCCHCarrierSwithcing). In periods including such information, the BS performs PUCCH reception assuming that the UE does not perform a PUCCH carrier change.

[0384] >> This time unit or slot length (i.e., the time length per slot) is determined by the UL subcarrier spacing setting configured in the cell. For example, at least one of the following is possible:

[0385] >>> A separate UL reference SCS for the PUCCH carrier change pattern is set, and the time unit is determined by the SCS value.

[0386] >>> Determined by the maximum or minimum SCS among the SCS of the UL BWP configured in the UE.

[0387] >>> Determined by the maximum or minimum SCS configurable in the cell. For example, determined by the smallest or largest SCS configuration u provided in the scs-SpecificCarrierList of FrequencyInfoUL or FrequencyInfoUL-SIB.

[0388] When one frame has a length of 10 ms, the slot length according to each SCS setting u is determined according to Table 1.

[0389] <Implementation B1> Deferring first within a PUCCH carrier, carrier switching second

[0390] When the BS transmits an SPS PDSCH configured / instructed to a UE and attempts to receive a HARQ-ACK response to the SPS PDSCH, if the HARQ-ACK reception cannot be received due to overlapping in time with one or more downlink symbols determined based on the PUCCH resource and PDSCH-to-HARQ-ACK timing instructed or configured to the UE, the BS assumes that the UE first performs a HARQ-ACK postponement procedure in an initial slot, determines a new target slot in which the HARQ-ACK response will be transmitted, and transmits the HARQ-ACK response in the slot, and attempts to receive the HARQ-ACK response in the new target slot.

[0391] As a result of the HARQ-ACK postponement process, i.e., due to the HARQ-ACK postponement, the HARQ-ACK response can be received at a position that is away from the relevant PDSCH transmission end time or the PUCCH reception start time indicated in the initial slot by more than a time interval T (e.g., a maximum deferral limit) (e.g., when the PDSCH transmission end time T_pdsch or the PUCCH reception start time T_pucch is taken as the PDSCH transmission end time T_pdsch or the PUCCH reception start time T_pucch, the HARQ-ACK response can be received at a time point that is later in time than T_pdsch+T or T_pucch+T), or when an explicit latency budget is specified for the service associated with the HARQ-ACK response transmitted by the UE. If it is determined that the determined target slot has difficulty meeting the delay budget (e.g., packet delay budget) given the delay budget (e.g., packet delay budget), or if the HARQ-ACK postponement process is not successful due to other reasons, the BS assumes that the UE attempts to change the PUCCH carrier and transmits PUCCH in the initial slot of another CC and receives a HARQ-ACK response.

[0392] The time interval T is a value that is predefined or determined by L1 signaling and / or higher layer signaling of the BS.

[0393] Implementation B1 minimizes the UE's PUCCH carrier change operation, thereby making maximum use of channel information for a corresponding CC that the UE acquires and holds in one CC.

[0394] <Realization B2> Carrier switching first, deferring second

[0395] When the BS transmits the SPS PDSCH configured / instructed to the UE and attempts to receive a HARQ-ACK response to the SPS PDSCH, if the HARQ-ACK reception determined based on the PUCCH resource and PDSCH-to-HARQ-ACK timing instructed or configured to the UE cannot be received overlapping in time with one or more downlink symbols, the BS receives the PUCCH transmission assuming that the UE has previously attempted a PUCCH carrier change in the initial slot. If it is predicted that the UE will not be able to transmit the PUCCH in the initial slot due to a PUCCH carrier change, the BS receives the PUCCH from the UE in the predicted target slot assuming that the UE has performed a HARQ-ACK postponement procedure.

[0396] For example, the BS attempts to transmit a HARQ-ACK PUCCH in the initial slot by changing the PUCCH carrier if possible, and only if the PUCCH cannot be transmitted in the initial slot even after changing the PUCCH carrier (e.g., if there is no CC in the initial slot with sufficient UL symbols for the PUCCH transmission), the BS further postpones the HARQ-ACK, determines a new target slot in which the HARQ-ACK will be transmitted, and receives the HARQ-ACK response, assuming that the HARQ-ACK response will be transmitted in the slot.

[0397] The BS assumes that when the UE further performs HARQ-ACK postponement, the UE performs HARQ-ACK postponement using some implementation of this specification, so that the UE can perform HARQ-ACK postponement taking into account multiple component carriers and minimize the round-trip time (RTT) required for receiving the PDSCH.

[0398] Alternatively, to simplify the operation of the UE, when the BS transmits an SPS PDSCH configured / instructed to the UE and attempts to receive a HARQ-ACK response thereto, if the HARQ-ACK transmission determined based on the PUCCH resource and PDSCH-to-HARQ-ACK timing configured or instructed to the UE cannot be transmitted overlapping in time with one or more downlink symbols, the BS performs PUCCH reception under the assumption that the UE attempts to change the PUCCH carrier in the initial slot to transmit the PUCCH, and does not perform a HARQ-ACK postponement procedure even if the PUCCH transmission cannot be performed in the initial slot due to the PUCCH carrier change. In other words, the BS performs PUCCH reception under the assumption that the UE does not perform a HARQ-ACK postponement procedure once the UE has changed the PUCCH carrier.

[0399] As another example, when a PUCCH carrier change is performed according to a PUCCH carrier change pattern, whether or not to allow a PUCCH carrier change at each time is determined according to the PUCCH carrier pattern. The BS assumes that the UE does not change the PUCCH carrier at a position where an initial CC is specified on the PUCCH carrier pattern, but changes the PUCCH carrier at a position where a carrier to be changed is specified. In this case, the BS receives the PUCCH, assuming that the UE changes the PUCCH carrier when a PUCCH carrier change is permitted, and performs a HARQ-ACK postponement process in a period when a PUCCH carrier change is not permitted.

[0400] <Realization B2-1> Deferring after carrier switching

[0401] When using implementation B2, when the BS transmits an SPS PDSCH configured / instructed to the UE and attempts to receive a HARQ-ACK response to the SPS PDSCH, if the HARQ-ACK reception determined based on the PUCCH resource and PDSCH-to-HARQ-ACK timing instructed or configured to the UE cannot be received as it overlaps in time with one or more downlink symbols, the BS assumes that the UE will first attempt to change the PUCCH carrier in the initial slot and transmit the PUCCH, and receives the PUCCH.

[0402] If the BS explicitly configures the UE with a target carrier for carrier change to be used in the uplink slot in which the corresponding PUCCH is scheduled, the BS assumes that the UE will perform a HARQ-ACK postponement process if the UE cannot transmit PUCCH in the initial slot after changing the PUCCH carrier, and performs PUCCH reception. In this case, the following methods can be considered:

[0403] * Method B2_1: The BS performs a carrier change to the target carrier configured for use in the initial slot, and postpones PUCCH reception to the target slot where PUCCH reception occurs on the target carrier. If the uplink carrier configured for use in the target slot is different from the target carrier, the BS assumes that the UE will perform a PUCCH carrier change to the target carrier again.

[0404] * Method B2_2: The BS performs a HARQ-ACK postponement process on the original carrier, postpones PUCCH reception to the target slot where PUCCH reception is performed on the original carrier, and performs carrier change to the target carrier that the UE is configured to use in the target slot, and performs PUCCH reception assuming that the UE will transmit PUCCH.

[0405] * Method B2_3: In the process of performing the HARQ-ACK postponement process as in the implementations A3 / B3, the BS considers the uplink carrier set to be used in each UL slot. For example, in the process of searching for the first UL slot in which the postponed PUCCH reception is performed, the BS considers whether the target uplink carrier of the slot (e.g., the uplink slot in which the PUCCH carrier to be used is set) is capable of reception, and if the PUCCH reception is possible, postpones the PUCCH reception to a slot in which the PUCCH reception is possible among the slots of the corresponding target uplink carrier.

[0406] <Implementation B3> HARQ-ACK deferral with PUCCH carrier switching

[0407] When a UE for which a BS has configured multiple component carriers (CCs) performs a HARQ-ACK postponement operation, in other words, when a HARQ-ACK response reception in an initial slot within an initial CC instructed / configured by the BS to the UE is received (also) in another target slot, the BS performs HARQ-ACK response reception assuming that the UE determines a target slot and a target CC for transmitting the HARQ-ACK response taking into account the CC configured by the UE. For example, when the BS transmits a (SPS) PDSCH configured / instructed by the BS to a UE for which a BS has configured multiple CCs and attempts to receive a HARQ-ACK response for the (SPS) PDSCH transmission, the BS determines a target slot and a target CC for which the corresponding HARQ-ACK response reception is actually performed, which are determined based on the PUCCH resource and PDSCH-to-HARQ-ACK timing instructed or configured by the BS to the UE, taking into account the configured CC and HARQ-ACK postponement. In some implementations of this specification, the BS determines a target slot and a target CC for which the UE transmits a PUCCH based on at least one of the following:

[0408] * Method B3_1: Among the slots within a predetermined time interval from the initial slot, a component carrier having sufficient consecutive available symbols (e.g., consecutive uplink or flexible symbols) to transmit the PUCCH resource of the deferred HARQ-ACK response is selected as the target PUCCH carrier. In this case, the slots of each component carrier having consecutive available symbols become the target slots of each component carrier. The predetermined time interval is a value indicated or set by the BS to the UE, or a maximum deferral limit derived by the UE based thereon.

[0409] * Method B3_2: When the target slot of each component carrier is determined, the component carrier with the smallest interval between the target slot and the initial slot is selected as the target CC.

[0410] * Method B3_3: When the target slot of each component carrier is determined, the component carrier in which the starting symbol of the PUCCH resource in which the delayed HARQ-ACK response is transmitted from the target slot of each component carrier is the earliest is selected as the target CC.

[0411] * Method B3_4: An activated component carrier is selected as the target CC.

[0412] * Method B3_5: A component carrier having the same subcarrier spacing as the initial CC is selected as the target CC.

[0413] * Method B3_6: A component carrier having a subcarrier spacing equal to or larger than that of the initial CC is selected as the target CC.

[0414] * Method B3_7: The same level of priority can be transmitted as the HARQ-ACK response that is postponed in the initial CC, i.e., if the HARQ-ACK response that is postponed in the initial CC is of high priority, a component carrier with PUCCH resources configured for high priority is selected as the target CC.

[0415] * Method B3_8: If more than one component carrier is selected due to all other conditions taken into account, the component carrier with the lower cell index is selected as the target CC.

[0416] Alternatively, in some implementations of this specification, the same method (described above) for the UE to determine the PUCCH carrier to be changed by the PUCCH carrier change may be used to determine the target CC. For example, the PUCCH cell for a slot is determined according to a predetermined or defined rule. In this case, , multiple In order to perform HARQ-ACK postponement operation taking into account the number of CCs, UE is Slot n, slot n+1, ..., slot n+k Each of Change PUCCH carrier in That Assuming that PUCCH is transmitted can be PUCCH carrier change in the earliest slot By applying , For a given PUCCH in initial slot n (i.e., a given PUCCH for initial slot n), Sending a deferred HARQ-ACK response can In other words, the BS determines a next PUCCH slot on the determined PUCCH cell according to a predefined rule for the PUCCH cell change of the UE, so as to support the UE to simultaneously configure HARQ-ACK postponement and PUCCH cell change, and determines whether the next PUCCH slot on the PUCCH cell for reception is a target PUCCH slot based on the HARQ-ACK postponement rule, where the next PUCCH slot is the slot in which the HARQ-ACK response is to be received. Kedjiwhere k is incremented on the initial cell.

[0417] Referring to FIG. 17, if the initial CC and the initial slot in which the BS schedules the UE to transmit the HARQ-ACK response are cell A and slot n, respectively, the BS and the UE determine that cell B is the cell for PUCCH transmission for slot n based on a predefined rule for PUCCH cell change. The BS determines whether the HARQ-ACK response can be received from the UE in the earliest slot m overlapping with slot n among the slots on cell B. For example, the BS determines a PUCCH resource for a UCI including the corresponding HARQ-ACK response in the earliest slot m overlapping with slot n among the slots on cell B, and determines whether the HARQ-ACK response can be received from the UE in slot m on cell B based on whether the PUCCH resource includes a downlink symbol. If the BS cannot receive the HARQ-ACK response from the UE in slot m on cell B, for example, if the PUCCH resource in slot m on cell B for the HARQ-ACK response includes a downlink symbol, the BS decides to postpone the reception of the HARQ-ACK response. In order to determine the target slot where the reception of the HARQ-ACK response is postponed, the BS determines the PUCCH cell in slot n+1 on cell A where the reception of the HARQ-ACK response is scheduled, and among the slots of cell B that are the PUCCH cell in slot n+1, determines whether slot m+2 mapped to slot n+1 is the target slot for reception of the postponed HARQ-ACK response. If the postponed HARQ-ACK response can be received in slot m+2 of cell B, the BS receives UCI including the postponed HARQ-ACK response in the PUCCH resource in slot m+2 of cell B. If the delayed HARQ-ACK response cannot be received in slot m+2 of cell B, for example if the PUCCH resource for UCI including the delayed response in slot m+2 of cell B includes a downlink symbol, the BS determines whether it can receive the delayed HARQ-ACK response in slot n+2 on cell A, which is the PUCCH cell for slot n+2, and determines whether slot n+2 on cell A is the target slot.

[0418] When considering the UL slots of each UL component carrier, the UL slots are counted taking into account the slot length (i.e., the time length of the slot) set for each HARQ-ACK codebook for each priority. In this case, to simplify the operation, the UL slot applied in the target CC when using the corresponding priority is considered as the UL slot for the target CC, taking into account the priority indicated / set in the source PUCCH where the carrier change is performed. For example, in a situation where slot lengths X and Y are used respectively for priorities 0 and 1 in cell A and slot lengths Y and Z are used respectively for priorities 0 and 1 in cell B, if the UCI of the PUCCH transmission indicated as priority 1 in cell A is transmitted in cell B due to the carrier change, the UCI of the PUCCH transmission is transmitted in the PUCCH of cell B based on slot length Z. In some implementations of this specification, the target CC is limited to CCs set with the same priority for this operation.

[0419] According to implementation B3, if the UE and BS consider HARQ-ACK postponement and PUCCH cell change together, it has the advantage that a shorter delay time can be ensured in relation to PUCCH transmission compared to performing only one of them or considering HARQ-ACK postponement and PUCCH cell change separately.

[0420] <Implementation B4> Maximum HARQ-ACK deferral considering PUCCH carrier switching

[0421] When a UE configured with multiple component carriers (CCs) by the BS performs HARQ-ACK postponement, in other words, when the UE receives a HARQ-ACK response in an initial slot in an initial CC instructed / configured by the BS in another target slot, the BS assumes that the UE determines the maximum HARQ-ACK postponement range max_defer taking into account the configured CC, and performs HARQ-ACK postponement only within the max_defer range. As an example, the BS assumes that the UE considers at least one of the following to determine the max_defer value:

[0422] > If the UE considers the set of configured PDSCH-to-HARQ_Feedback-Timing K1 to determine max_defer, e.g., if it considers the configured dlDataToUL-ACK, dl-DataToUL-ACK-r16, or dl-DataToUL-ACKForDCIFormat1_2,

[0423] >> The UE only considers the UL component carriers used when not performing a PUCCH carrier change, e.g., the K1 set configured for the primary cell.

[0424] >> The UE considers K1 sets of all candidate cells subject to the configured PUCCH carrier change.

[0425] >> The UE only considers the K1 set configured for the available UL component carriers configured for the PUCCH carrier change pattern at the time of HARQ-ACK postponement.

[0426] > If the UE uses max_defer included in each SPS PDSCH configuration to determine max_defer, the corresponding value shall be used without modification. For reference, the parameter max_defer in the SPS PDSCH configuration indicates the maximum number of slots or subslots in which the transmission of the SPS HARQ-ACK in the slot or subslot can be postponed.

[0427] When the UE considers the set of configured PDSCH-to-HARQ_feedback timing K1 to determine max_defer, the BS assumes that the UE determines, for example, the maximum K1 value in the configured K1 set as the maximum range of HARQ-ACK deferral max_defer. That is, even if HARQ-ACK deferral is performed, the HARQ-ACK deferral operation is performed such that the difference between the slot position of the deferred HARQ-ACK PUCCH and the corresponding PDSCH reception is limited to max_defer.

[0428] In order to determine the maximum K1 value or to apply the determined max_defer to UL component carriers with different actual slot lengths (e.g., different subcarrier spacings), the max_defer time length needs to be determined. That is, when PUCCH carrier change is used, the time point of PUCCH transmission postponed from the PDSCH reception time point is limited by the actually calculated max_defer time length. To this end, at least one of the following is considered:

[0429] > The effective slot offset length applied with the subcarrier spacing of the UL component carrier used when the PUCCH carrier is not changed is used as the time length of max_defer. That is, the BS assumes that even if the UE postpones HARQ-ACK due to a PUCCH carrier change, the HARQ-ACK postponement due to the PUCCH carrier change does not exceed the maximum HARQ-ACK postponement range when the PUCCH carrier is not changed.

[0430] > Determined by the UL reference SCS or UL reference cell used for the PUCCH carrier change pattern. The PUCCH carrier change pattern is predefined / configured based on the UL reference SCS or UL cell, the BS sets a max_defer value for each SPS configuration based on the UL reference SCS or UL reference cell, and the UE interprets the set max_defer value based on the UL reference SCS or UL reference cell to determine the (maximum) slot range in which HARQ-ACK can be deferred. The UL reference SCS or UL reference cell is configured or defined to be commonly used for all SPS configurations (e.g., the primary cell or Pcell is predefined as the UL reference cell). Alternatively, the UL reference SCS or UL reference cell may be configured for each SPS configuration.

[0431] The time length of max_defer is determined by the SCS with the maximum or minimum subcarrier spacing among the UL BWPs configured for all candidate cells that are targets of the PUCCH carrier change.

[0432] The duration of max_defer is determined by the maximum or minimum subcarrier spacing that can be set in the cell. For example, the duration of max_defer is determined by the minimum or maximum SCS configuration u provided in the scs-SpecificCarrierList of the RRC configuration FrequencyInfoUL or FrequencyInfoUL-SIB.

[0433] > Depending on the given subcarrier spacing, max_defer * (number of OFDM symbols per slot) * (symbol length for a given SCS) or max_defer * (10 ms) / (number of slots per frame for a given SCS) is used as the actual max_defer duration.

[0434] When a specific cell or a specific SCS is assumed to apply max_defer, the boundary of the maximum deferral range determined as max_defer may overlap with the postponed PUCCH reception. For example, in a general single carrier operation, the boundary of the maximum deferral range determined as max_defer coincides with the slot boundary, and there is no difficulty in checking the validity of the deferral operation. In a general single carrier operation, the BS and the UE determine that the PUCCH is valid if it is postponed within the boundary of the deferral range, and invalid if it is postponed outside the boundary. However, in the HARQ-ACK postponement process considering the PUCCH carrier change, the boundary of the determined maximum deferral range may not coincide with the slot boundary of the uplink carrier where the PUCCH is received.

[0435] If the boundary of the maximum deferral range does not coincide with the slot boundary of the uplink carrier where the PUCCH is received, the boundary of the deferral range may pass through the PUCCH resource. In this case, it is difficult to determine whether the corresponding PUCCH should be dropped beyond the boundary of the deferral range. In some embodiments of this specification, the following can be considered to determine the validity of the dropping and deferral operation of the PUCCH in this case.

[0436] Method B4_1: The boundaries of the deferral range are redefined based on the slots of the PUCCH carrier. For this purpose, at least one of the following is possible:

[0437] ** Method B4_1-1: The BS determines that a slot of a PUCCH carrier that overlaps in time with one or more slots within the range in which deferral operation is possible based on the reference cell or reference SCS used to determine the boundary of the deferral range is within the range in which deferral operation is possible.

[0438] ** Method B4_1-2: The BS determines that a slot of a PUCCH carrier that overlaps in time with a slot within the range for which deferral operation is possible (i.e., more than half of the symbols that make up the slot overlap) by more than half based on the reference cell or reference SCS used to determine the boundary of the deferral range is within the range for which deferral operation is possible.

[0439] ** Method B4_1-2: The BS determines that the slots of the PUCCH carrier that are completely included in the range where the deferral operation is possible based on the reference cell or reference SCS used to determine the boundary of the deferral range are within the range where the deferral operation is possible. In other words, the BS assumes that only slots that end before the boundary of the deferral range are within the range where the deferral operation is possible.

[0440] Method B4_2: Using the PUCCH resource as a reference, compare the PUCCH resource with the boundary of the deferral range to judge the validity of the deferral operation. To this end, at least one of the following may be considered:

[0441] ** Method B4_2-1: The BS determines that the deferral operation is valid if one or more symbols of the PUCCH resource are included in the range in which the deferral operation is possible. In other words, the BS determines that the deferral operation is invalid only if the starting symbol of the PUCCH resource is later than the boundary of the deferral range.

[0442] ** Method B4_2-1: The BS determines that the deferral operation is valid if more than half of the symbols of the PUCCH resource are included in the range where the deferral operation is possible.

[0443] ** Method B4_2-2: The BS determines that the deferral operation is valid only if all symbols of the PUCCH resource are within the range in which the deferral operation is possible. In other words, if the last symbol of the PUCCH resource is later than the boundary of the deferral range, the BS determines that the deferral operation is invalid.

[0444] <Implementation A5> Reference subcarrier spacing for PUCCH cell / carrier switching

[0445] In some implementations of this specification, a PUCCH cell / carrier change means that the UE randomly changes the PUCCH cell / carrier according to a predefined rule, as described above, to transmit a PUCCH, and the BS receives the corresponding transmission of the UE in the changed PUCCH cell / carrier. The predefined rule may be as follows:

[0446] * The PUCCH radio resource is determined by the PRI included in the DCI, and if the DCI includes a PUCCH carrier indication, the PUCCH carrier change is performed according to the PUCCH carrier indication.

[0447] * A PUCCH carrier change pattern is configured in the UE via higher layer signaling from the BS. The PUCCH carrier change pattern is information that lists cells to be used in a certain time unit (e.g., slots for a given SCS configuration) in a certain time period (e.g., dozens of slots, one frame, or 10 ms). If the UE performs a PUCCH carrier / cell change between two cells, a primary cell and a SCell configured as a target for the PUCCH carrier / cell change, the PUCCH carrier change pattern is information that lists whether the primary cell or the configured SCell is used in each time unit of a certain time period. The length of the time unit or slot is determined by the UL subcarrier spacing configuration configured in the cell. As an example, the reference SCS configuration u_ref according to referenceSubcarrierSpacing provided in tdd-UL-DL-ConfigurationCommon is used to determine the length of the time unit or slot.

[0448] When one frame has a length of 10 ms, the slot length according to each SCS setting u is determined according to Table 1.

[0449] As mentioned above, the reference SCS configuration provided to the UE by tdd-UL-DL-ConfigurationCommon is used to determine the slot length of the PUCCH cell / carrier change pattern. However, since this parameter is not essential for UE operation, the BS may not configure this parameter for network configuration and operation. In some implementations of this specification, in this case, i.e., if the BS does not configure the UE with higher layer parameters required for interpreting the PUCCH cell / carrier change pattern, the BS and the UE interpret the PUCCH cell / carrier change pattern by at least one of the following:

[0450] * Method B5_1: In order to prevent such a case, the reference SCS setting in tdd-UL-DL-ConfigurationCommon is defined as a prerequisite for PUCCH cell / carrier change. In other words, it is stipulated that PUCCH cell / carrier change is performed only when the reference SCS parameter in tdd-UL-DL-ConfigurationCommon is set. As an example, if the BS does not provide the UE with the reference SCS setting in tdd-UL-DL-ConfigurationCommon, it is assumed that the UE does not perform the PUCCH cell / carrier change operation. Or, as another example, the tdd-UL-DL-ConfigurationCommon parameter set is defined as a prerequisite element for the UE's PUCCH cell / carrier change capability. In other words, it is stipulated that PUCCH cell / carrier change is performed only when the information element (IE) tdd-UL-DL-ConfigurationCommon is set in the UE. This ensures that when the BS configures the UE for PUCCH cell / carrier change behavior, the tdd-UL-DL-ConfigurationCommon parameter set is always given.

[0451] * Method B5_2: In preparation for the case where the tdd-UL-DL-ConfigurationCommon parameter set is not provided to the UE, a separate UL reference SCS for the PUCCH carrier modification pattern is configured, and the slot length of the PUCCH cell / carrier modification pattern is determined by the corresponding SCS value only if the tdd-UL-DL-ConfigurationCommon parameter set is not provided to the UE.

[0452] * Method B5_3: If the tdd-UL-DL-ConfigurationCommon parameter set is not provided, the BS assumes that the UE determines the slot length of the PUCCH cell / carrier change pattern according to the SCS with the maximum or minimum subcarrier spacing among all UL BWPs configured in the UE (in the primary cell). Alternatively, for the sake of simplicity of the UE operation, the slot length of the PUCCH cell / carrier change pattern is always determined according to the SCS with the maximum or minimum subcarrier spacing among all UL BWPs configured in the UE (in the primary cell), regardless of whether the tdd-UL-DL-ConfigurationCommon parameter set is provided in the UE.

[0453] * Method B5_4: If the tdd-UL-DL-ConfigurationCommon parameter set is not provided to the UE, the slot length of the PUCCH carrier change pattern is determined by the maximum or minimum subcarrier spacing configurable in the primary cell. As an example, the slot length of the PUCCH cell / carrier change pattern is determined by the smallest or largest SCS configuration u provided in the scs-SpecificCarrierList of FrequencyInfoUL or FrequencyInfoUL-SIB. Alternatively, for the simplification of the UE operation, the slot length of the PUCCH carrier change pattern is always determined by the maximum or minimum subcarrier spacing configurable in the primary cell, regardless of whether the tdd-UL-DL-ConfigurationCommon parameter set is provided.

[0454] * Method B5_5: If the tdd-UL-DL-ConfigurationCommon parameter set is not provided to the UE, the slot length of the PUCCH cell / carrier change pattern is determined using a predefined SCS value (e.g., u=0; 15 kHz). Alternatively, to simplify the UE operation, the slot length of the PUCCH cell / carrier change pattern is always determined using a predefined SCS value (e.g., u=0; 15 kHz), regardless of whether the tdd-UL-DL-ConfigurationCommon parameter set is provided to the UE or not.

[0455] * Method B5_6: If the tdd-UL-DL-ConfigurationCommon parameter set is not provided to the UE, the slot length of the PUCCH cell / carrier change pattern is determined by the SCS of the BWP with the lowest id among all UL BWPs configured to the UE (for the primary cell). Alternatively, for the simplification of the UE operation, the slot length of the PUCCH cell / carrier change pattern is always determined by the SCS of the BWP with the lowest id among all UL BWPs configured to the UE (for the primary cell), regardless of whether the tdd-UL-DL-ConfigurationCommon parameter set is provided to the UE.

[0456] * Method B5_7: If the tdd-UL-DL-ConfigurationCommon parameter set is not provided to the UE, the slot length of the PUCCH cell / carrier change pattern is determined by the SCS of the initial uplink BWP (e.g., the BWP provided by the RRC parameter initialUplinkBWP) configured to the UE (for the primary cell). Alternatively, for the simplification of the UE operation, the slot length of the PUCCH cell / carrier change pattern is always determined by the SCS of the initial uplink BWP (e.g., the BWP provided by the RRC parameter initialUplinkBWP) configured to the UE (for the primary cell), regardless of whether the tdd-UL-DL-ConfigurationCommon parameter set is provided to the UE.

[0457] * Method B5_8: If the tdd-UL-DL-ConfigurationCommon parameter set is not provided to the UE, the slot length of the PUCCH cell / carrier change pattern is determined by the SCS of the first active uplink BWP (e.g., the BWP provided by the RRC parameter firstActiveUplinkBWP-Id) configured to the UE (in the primary cell). Alternatively, for the sake of simplicity of UE operation, the slot length of the PUCCH cell / carrier change pattern is always determined by the SCS of the first active BWP (e.g., the BWP provided by the RRC parameter firstActiveUplinkBWP-Id) configured to the UE (in the primary cell), regardless of whether the tdd-UL-DL-ConfigurationCommon parameter set is provided to the UE.

[0458] The UE and the BS can use multiple methods mentioned above simultaneously and in a complementary manner. For example, the UE and the BS use both the method B5_1 and the method B5_2, and use the method B5_1 when the tdd-UL-DL-ConfigurationCommon parameter set is provided, and use the method B5_2 when the tdd-UL-DL-ConfigurationCommon parameter set is not provided.

[0459] In some implementations of this specification, the BS performs RRC configuration to configure the UE with component carriers that the UE can use through a cell configuration process. When the BS configures and / or instructs the UE to receive the SPS PDSCH and transmit a PUCCH for a HARQ-ACK response thereto, the UE determines or changes the carrier on which the PUCCH for the HARQ-ACK response is transmitted and determines or changes the slot on which the PUCCH is transmitted according to some implementations of this specification. The BS receives UCI (including HARQ-ACK information for the PDSCH) on the PUCCH resource in the determined / changed slot on the determined / changed carrier according to some implementations of this specification.

[0460] According to some implementations of this specification, when the BS and UE can use multiple CCs, they determine whether to perform a PUCCH carrier change and / or a HARQ-ACK postponement for uplink transmissions configured / indicated on unavailable resources based on the TDD configuration and CA configuration, or perform a HARQ-ACK postponement taking into account multiple CCs (e.g., taking into account a PUCCH carrier change between multiple CCs according to a pre-determined / defined rule). When the UE can use multiple CCs with different TDD configurations for communication, the BS and UE can determine / change the PUCCH transmission carrier and delay the HARQ-ACK response according to some implementations of this specification, thereby minimizing the delay time of transmission / reception that is dropped due to a pre-determined / defined condition. According to some implementations of this specification, the BS can predict such UE behavior without ambiguity between the BS and the UE. Some implementations of this specification allow a UE to perform uplink transmissions that are dropped by a TDD UL-DL pattern with minimal latency, and a BS to receive uplink transmissions that are dropped by a TDD UL-DL pattern with minimal latency, thereby enabling efficient or minimal use of uplink resources across the system.

[0461] The UE performs operations according to some embodiments of this specification in connection with transmitting HARQ-ACK information. The UE includes at least one transceiver, at least one processor, and at least one computer memory operably connected to the at least one processor and having instructions stored thereon that, when executed, cause the at least one processor to perform operations according to some embodiments of this specification. A processing device for a UE includes at least one processor and at least one computer memory operably connected to the at least one processor and having instructions stored thereon that, when executed, cause the at least one processor to perform operations according to some embodiments of this specification. A computer readable (non-volatile) storage medium stores at least one computer program including instructions that, when executed by the at least one processor, cause the at least one processor to perform operations according to some embodiments of this specification. A computer program or computer program product is stored on at least one computer readable (non-volatile) storage medium and includes instructions that, when executed, cause (the at least one processor) to perform operations according to some embodiments of this specification. In the UE, the processing device, the computer-readable (non-volatile) storage medium, and / or the computer program product, the operations include: performing a PDSCH reception; for a first cell slot n on a first cell where a HARQ-ACK transmission for the PDSCH reception is scheduled and a PUCCH cell change, determining a PUCCH cell among a plurality of cells including the first cell and a second cell different from the first cell based on a predetermined rule, determining a PUCCH cell slot associated with the first cell slot n among slots on the PUCCH cell for the first cell slot n, and determining a target slot to which the HARQ-ACK transmission is postponed based on overlapping of the HARQ-ACK transmission with a downlink symbol in the PUCCH cell slot on the PUCCH cell for the first cell slot n.

[0462] In some implementations, the first cell slot n is the slot in which a HARQ-ACK transmission for the PDSCH is scheduled.

[0463] In some implementations, the plurality of cells are configured for a PUCCH cell change. Determining the PUCCH cell among the plurality of cells includes: determining the PUCCH cell for the first cell slot n among the plurality of cells based on the predetermined rule for the PUCCH cell change.

[0464] In some implementations, the target slot is the earliest slot among PUCCH cell slots in which the HARQ-ACK transmission can be performed, determined based on the predetermined rule and a first cell slot on the first cell.

[0465] In some implementations, the method further includes transmitting the HARQ-ACK in the PUCCH cell slot on the PUCCH cell for the first cell slot n based on the HARQ-ACK transmission not overlapping with downlink symbols in the PUCCH cell slot on the PUCCH cell for the first cell slot n.

[0466] In some implementations, determining the target slot includes: determining a PUCCH cell for a first cell slot n+k on the first cell based on the predetermined rule, where k is a positive integer, determining a PUCCH cell for a first cell slot n+k+1 on the first cell based on an overlap of a HARQ-ACK transmission with a downlink symbol in a PUCCH cell slot associated with the first cell slot n+k among slots on the PUCCH cell for the first cell slot n+k, and determining whether the HARQ-ACK transmission occurs in a PUCCH slot on the PUCCH cell for the first cell slot n+k+1 associated with the first cell slot n+k+1.

[0467] In some implementations, the PDSCH reception is a semi-persistent scheduled PDSCH reception.

[0468] The BS performs operations according to some embodiments of this specification in connection with receiving the HARQ-ACK information. The BS includes at least one transceiver, at least one processor, and at least one computer memory operably connected to the at least one processor and having instructions stored thereon that, when executed, cause the at least one processor to perform operations according to some embodiments of this specification. The processing device for the BS includes at least one processor and at least one computer memory operably connected to the at least one processor and having instructions stored thereon that, when executed, cause the at least one processor to perform operations according to some embodiments of this specification. The computer readable (non-volatile) storage medium stores at least one computer program including instructions that, when executed by the at least one processor, cause the at least one processor to perform operations according to some embodiments of this specification. The computer program or computer program product is stored on at least one computer readable (non-volatile) storage medium and includes instructions that, when executed, cause (the at least one processor) to perform operations according to some embodiments of this specification. In the BS, the processing device, the computer-readable (non-volatile) storage medium, and / or the computer program product, the operations include performing a PDSCH transmission; determining a PUCCH cell among a plurality of cells including the first cell and a second cell different from the first cell based on a predetermined rule for a first cell slot n on a first cell for which HARQ-ACK reception for the PDSCH transmission is scheduled and a PUCCH cell change; determining a PUCCH cell slot associated with the first cell slot n among slots on the PUCCH cell for the first cell slot n; and determining a target slot where the HARQ-ACK reception is postponed based on overlapping of the HARQ-ACK reception with a downlink symbol in the PUCCH cell slot on the PUCCH cell for the first cell slot n.

[0469] In some implementations, the first cell slot n is the slot in which a HARQ-ACK transmission for the PDSCH is scheduled.

[0470] In some implementations, the plurality of cells are configured for a PUCCH cell change. Determining the PUCCH cell among the plurality of cells includes determining the PUCCH cell for the first cell slot n among the plurality of cells based on the predetermined rule for the PUCCH cell change.

[0471] In some implementations, the target slot is the earliest slot among the PUCCH cell slots in which the HARQ-ACK reception can be performed, determined based on the predetermined rule and a first cell slot on the first cell.

[0472] In some implementations, the method further includes receiving the HARQ-ACK in the PUCCH cell slot on the PUCCH cell for the first cell slot n based on the HARQ-ACK reception not overlapping with downlink symbols in the PUCCH cell slot on the PUCCH cell for the first cell slot n.

[0473] In some implementations, determining the target slot includes determining a PUCCH cell for a first cell slot n+k on the first cell based on the predetermined rule, where k is a positive integer, and determining a PUCCH cell for a first cell slot n+k+1 on the first cell based on the HARQ-ACK reception overlapping with a downlink symbol in a PUCCH cell slot associated with the first cell slot n+k among slots on the PUCCH cell for the first cell slot n+k; and determining whether the HARQ-ACK reception occurs in a PUCCH slot on the PUCCH cell for the first cell slot n+k+1 associated with the first cell slot n+k+1.

[0474] In some implementations, the PDSCH transmission is a semi-persistent scheduled PDSCH transmission.

[0475] The above disclosed examples of the present invention are provided to enable those skilled in the art to which the present invention pertains to embody and practice the present invention. Although the present invention has been described above with reference to preferred embodiments, those skilled in the art can make various modifications and changes to the present invention. Therefore, the present invention is not intended to be limited to the embodiments disclosed herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein. [Industrial Applicability]

[0476] Implementations of the present invention may be used in a BS or user equipment, or other equipment, in a wireless communication system.

Claims

1. A method performed by a user equipment (UE), comprising: performing a physical downlink shared channel (PDSCH) reception; determining an initial slot and an initial cell in which the UE will initially perform a hybrid automatic repeat request-acknowledgement (HARQ-ACK) transmission for the PDSCH reception; determining a target slot and a target cell for which the HARQ-ACK transmission is to be postponed based on an overlap of the HARQ-ACK transmission with a downlink symbol in the initial slot; The initial cell and the target cell are determined from a plurality of cells for a physical uplink control channel (PUCCH) cell change; The UE determines, as the target slot and the target cell, an earliest slot and corresponding cell available for the HARQ-ACK transmission based on the PUCCH cell change.

2. 2. The method of claim 1, wherein determining the initial slot and the initial cell comprises determining the initial cell for the slot n of the plurality of cells based on: i) a slot n in which the HARQ-ACK transmission for the PDSCH reception is scheduled; and ii) the PUCCH cell change.

3. The step of determining the target slot and the target cell includes: determining a PUCCH cell for slot n+k among the plurality of cells based on the PUCCH cell change, where k is a positive integer; and determining the PUCCH cell slot and the PUCCH cell as the target slot and the target cell, respectively, based on the HARQ-ACK transmission not overlapping with downlink symbols in a PUCCH cell slot associated with the slot n+k among slots of the PUCCH cell for the slot n+k.

4. The method of claim 1 , wherein the PDSCH reception is semi-persistently scheduled PDSCH reception.

5. The method according to claim 1, wherein the PUCCH cell change is performed based on a PUCCH cell change pattern.

6. The PUCCH cell change pattern is configured by higher layer signaling, The PUCCH cell change pattern informs the UE of an applicable PUCCH cell for each of a plurality of time units; The method of claim 5 , wherein a length of each of the plurality of time units is determined based on a subcarrier spacing for the PUCCH cell changing pattern.

7. The target slot is determined among slots, The method according to any one of claims 1 to 4, wherein the time difference between each of the slots and the slot of the PDSCH reception in relation to the subcarrier spacing of a primary cell among the plurality of cells for the PUCCH cell change is not longer than a maximum HARQ-ACK deferral range.

8. A UE (user equipment), At least one transceiver; At least one processor; at least one computer memory operatively connected to the at least one processor and configured to store instructions that, when executed, cause the at least one processor to perform operations; The operation includes: performing physical downlink shared channel (PDSCH) reception; determining an initial slot and an initial cell in which the UE will initially perform a hybrid automatic repeat request-acknowledgement (HARQ-ACK) transmission for the PDSCH reception; determining a target slot and a target cell for which the HARQ-ACK transmission is to be postponed based on an overlap of the HARQ-ACK transmission with a downlink symbol in the initial slot; The initial cell and the target cell are determined from a plurality of cells for a physical uplink control channel (PUCCH) cell change; The operations include: the UE determining, as the target slot and the target cell, an earliest slot and corresponding cell available for the HARQ-ACK transmission based on the PUCCH cell change.

9. A processing device, comprising: At least one processor; at least one computer memory operatively connected to the at least one processor and configured to store instructions that, when executed, cause the at least one processor to perform operations; The operation includes: performing physical downlink shared channel (PDSCH) reception; determining an initial slot and an initial cell in which a user equipment (UE) will initially perform a hybrid automatic repeat request-acknowledgement (HARQ-ACK) transmission in response to the PDSCH reception; determining a target slot and a target cell for which the HARQ-ACK transmission is to be postponed based on an overlap of the HARQ-ACK transmission with a downlink symbol in the initial slot; The initial cell and the target cell are determined from a plurality of cells for a physical uplink control channel (PUCCH) cell change; The operations include determining an earliest slot and corresponding cell available for the HARQ-ACK transmission based on the PUCCH cell change as the target slot and the target cell.

10. A computer-readable storage medium configured to store at least one program code including instructions, The instructions, when executed, cause at least one processor to: performing physical downlink shared channel (PDSCH) reception; determining an initial slot and an initial cell in which a user equipment (UE) will initially perform a hybrid automatic repeat request-acknowledgement (HARQ-ACK) transmission in response to the PDSCH reception; determining a target slot and a target cell for which the HARQ-ACK transmission is to be postponed based on the overlap of the HARQ-ACK transmission with a downlink symbol in the initial slot; The initial cell and the target cell are determined from a plurality of cells for a physical uplink control channel (PUCCH) cell change; The operations include determining an earliest slot and corresponding cell available for the HARQ-ACK transmission based on the PUCCH cell change as the target slot and the target cell.

11. A method performed by a base station (BS), comprising: performing a physical downlink shared channel (PDSCH) transmission; determining an initial slot and an initial cell in which the BS will initially perform hybrid automatic repeat request-acknowledgement (HARQ-ACK) reception for the PDSCH transmission; determining a target slot and a target cell for which the HARQ-ACK reception is to be postponed based on the overlap of the HARQ-ACK reception with a downlink symbol in the initial slot; The initial cell and the target cell are determined from a plurality of cells for a physical uplink control channel (PUCCH) cell change; The method, wherein an earliest slot and corresponding cell available for the HARQ-ACK reception based on the PUCCH cell change is determined as the target slot and the target cell.

12. A BS (base station), At least one transceiver; At least one processor; at least one computer memory operatively connected to the at least one processor and configured to store instructions that, when executed, cause the at least one processor to perform operations; The operation includes: performing a physical downlink shared channel (PDSCH) transmission; determining an initial slot and an initial cell in which the BS will initially perform hybrid automatic repeat request-acknowledgement (HARQ-ACK) reception for the PDSCH transmission; determining a target slot and a target cell for which the HARQ-ACK reception is to be postponed based on the overlap of the HARQ-ACK reception with a downlink symbol in the initial slot; The initial cell and the target cell are determined from a plurality of cells for a physical uplink control channel (PUCCH) cell change; The BS determines the earliest slot and corresponding cell available for the HARQ-ACK reception based on the PUCCH cell change as the target slot and the target cell.

13. Determining the initial slot and the initial cell includes:

13. The BS of claim 12, further comprising: determining the initial cell for the slot n of the plurality of cells based on: i) a slot n in which the HARQ-ACK reception for the PDSCH transmission is scheduled; and ii) the PUCCH cell change.

14. Determining the target slot and the target cell includes: determining a PUCCH cell for slot n+k among the plurality of cells based on the PUCCH cell change, where k is a positive integer; and determining the PUCCH cell slot and the PUCCH cell as the target slot and the target cell, respectively, based on the HARQ-ACK reception not overlapping with downlink symbols in a PUCCH cell slot associated with the slot n+k among slots of the PUCCH cell for the slot n+k.

15. The BS of claim 12, wherein the PDSCH transmission is a semi-persistently scheduled PDSCH transmission.

16. The BS according to claim 12, wherein the PUCCH cell change is performed based on a PUCCH cell change pattern.

17. The PUCCH cell change pattern is configured by higher layer signaling, The PUCCH cell change pattern informs a UE (user equipment) of an applicable PUCCH cell for each of a plurality of time units, The BS of claim 16, wherein a length of each of the plurality of time units is determined based on a subcarrier spacing for the PUCCH cell change pattern.

18. The target slot is determined among slots, The BS according to any one of claims 12 to 15, wherein the time difference between each of the slots and the slot of the PDSCH transmission in relation to the subcarrier spacing of a primary cell among the plurality of cells for the PUCCH cell change is not longer than the maximum HARQ-ACK deferral range.

Images