WO2024172573A1 - Method and device for uplink resource allocation based on update of transmission configuration indicator in communication system - Google Patents

Abstract

A method of a UE, according to one embodiment of the present disclosure, may comprise the steps of: receiving upper layer signaling including a first timing offset, BAT and TCI type information; receiving indication information for a unified TCI for two or more TRPs; communicating with the two or more TRPs on the basis of the first timing offset and the unified TCI; receiving TCI state change indication information from one TRP among the two or more TRPs; and, as a response to receiving the TCI state change indication information, determining a first slot for transmitting HARQ feedback through a PUCCH, on the basis of the first timing offset and the BAT, and transmitting the HARQ feedback to the two or more TRPs by means of a first PUCCH.

Description

Method and device for uplink resource allocation based on update of transmission setup indicator in communication system

The present disclosure relates to improved communication technology, and more particularly, to an uplink resource allocation technology based on Transmission Configuration Indicator (TCI) update.

Communication networks (e.g., 5G communication networks, 6G communication networks, etc.) are being developed to provide improved communication services compared to existing communication networks (e.g., LTE (long term evolution), LTE-A (advanced), etc.). A 5G communication network (e.g., NR (new radio) communication network) can support not only a frequency band below 6 GHz but also a frequency band above 6 GHz. That is, the 5G communication network can support FR1 band and/or FR2 band. A 5G communication network can support various communication services and scenarios compared to an LTE communication network. For example, usage scenarios of a 5G communication network can include eMBB (enhanced Mobile BroadBand), URLLC (Ultra Reliable Low Latency Communication), mMTC (massive Machine Type Communication), etc.

6G communication networks can support various communication services and scenarios compared to 5G communication networks. 6G communication networks can satisfy requirements of ultra-performance, ultra-bandwidth, ultra-space, ultra-precision, ultra-intelligence, and/or ultra-reliability. 6G communication networks can support various and wide frequency bands and can be applied to various usage scenarios (e.g., terrestrial communication, non-terrestrial communication, sidelink communication, etc.).

Meanwhile, in order to ensure reliability of downlink and improve transmission rate in cell-edge area, 5G NR can use physical channels separately or sharedly for each transmission reception point (TRP) or panel. Communication using this method can be representative target use cases such as URLLC and eMBB.

On the other hand, 3GPP Rel-18, which performs the standardization work of wireless communications, decided to extend the unified Transmission Configuration Indicator (TCI) framework targeting the single TRP (sTRP) designed in 3GPP Rel-17 to the mTRP system. Therefore, a method for configuring and transmitting PUCCH related to this is required.

The purpose of the present disclosure to solve the above problems is to provide a method and device for configuring PUCCH and transmitting PUCCH in an integrated TCI framework targeting mTRP in a communication system.

According to an embodiment of the present disclosure for achieving the above object, a method of a user equipment (UE), the method comprising: receiving upper layer signaling including a first timing offset, a beam application time (BAT), and Transmission Configuration Indicator (TCI) type information; receiving indication information for a unified TCI for two or more transmission and reception points (TRPs); communicating with the two or more TRPs based on the first timing offset and the unified TCI; receiving TCI state change indication information from one of the two or more TRPs; in response to receiving the TCI state change indication information, determining a first slot in which to transmit a Hybrid automatic repeat request (HARQ) feedback over a Physical Uplink Control Channel (PUCCH) based on the first timing offset and the BAT; and may include a step of transmitting the HARQ feedback for each of the two or more TRPs to the two or more TRPs through the first PUCCH in the determined first slot.

The method may further include: a step of checking whether the downlink control information (DCI) includes a second timing offset when the TCI state change indication information is indicated by downlink control information; a step of determining a second slot for transmitting the HARQ feedback based on the second timing offset and the BAT when the second timing offset is included; and a step of transmitting the HARQ feedback to the two or more TRPs through a second PUCCH in the determined second slot.

The second slot to transmit the HARQ feedback may be determined as a slot index calculated as the sum of a last slot index of a physical downlink shared channel (PDSCH) received from the two or more TRPs, a value set by the second timing offset, and an additional slot index value determined by the BAT value.

If the number of symbols indicated by the BAT is not equal to the number of symbols constituting one slot, the additional slot index value may be a value obtained by adding "1" to the largest integer among the values obtained by dividing the number of symbols indicated by the BAT by the number of symbols constituting one slot, and if the number of symbols indicated by the BAT is a multiple of N of the symbols constituting one slot (where N is a natural number), the additional slot index value may be a value obtained by dividing the number of symbols indicated by the BAT by the number of symbols constituting one slot.

The first slot may be determined as a slot index calculated as the sum of a last slot index of a physical downlink shared channel (PDSCH) received from the two or more TRPs, a value set by the first timing offset, and an additional slot value determined by the BAT value.

If the number of symbols indicated by the BAT is not equal to the number of symbols constituting one slot, the additional slot index value may be a value obtained by adding "1" to the largest integer among the values obtained by dividing the number of symbols indicated by the BAT by the number of symbols constituting one slot, and if the number of symbols indicated by the BAT is a multiple of N of the symbols constituting one slot (where N is a natural number), the additional slot index value may be a value obtained by dividing the number of symbols indicated by the BAT by the number of symbols constituting one slot.

The method may further include a step of grouping TRPs for which the BAT is required among the two or more TRPs, when the BAT is set to a value smaller than one slot and the TCI state change indication information included in a single downlink control information (DCI) is set to transmit the HARQ feedback through one third PUCCH for the two or more TRPs; a step of determining different third PUCCH resource indices for transmitting the HARQ feedback for each of the grouped TRPs; and a step of transmitting the HARQ feedback to the grouped TRPs through a third PUCCH resource indicated by the determined third PUCCH resource index.

The above HARQ feedback may include a TRP identifier (ID) for each of the grouped TRPs.

The above grouped TRPs include a first TRP and a second TRP, and the third PUCCH for the first TRP includes a fourth PUCCH resource directly set by the first TRP, and the fifth PUCCH resource for the second TRP may be allocated from a symbol after the BAT value if the BAT is required.

The above fifth PUCCH resource may have the same format as the above fourth PUCCH resource.

A method of a base station according to one embodiment of the present disclosure may include: transmitting, to a user equipment (UE), upper layer signaling including a first timing offset, a beam application time (BAT), and Transmission Configuration Indicator (TCI) type information; transmitting, to the UE, indication information for a unified TCI for two or more transmission and reception points (TRPs) connected to the base station; communicating with the UE through the two or more TRPs based on the first timing offset and the unified TCI; transmitting TCI state change indication information to the UE through one of the two or more TRPs; and receiving, in response to the TCI state change indication information, a hybrid automatic repeat request (HARQ) feedback for each of the two or more TRPs from the UE through a first Physical Uplink Control Channel (PUCCH) in a first slot,

The above first slot may be a slot determined based on the first timing offset and the BAT.

The method may further include: transmitting downlink control information (DCI) including the TCI state change indication information and the second timing offset to the UE; and receiving the HARQ feedback in a second slot based on the second timing offset and the BAT.

The second slot to transmit the HARQ feedback may be determined as a slot index calculated as the sum of a last slot index of a physical downlink shared channel (PDSCH) transmitted through the two or more TRPs, a value set by the second timing offset, and an additional slot index value determined by the BAT value.

A user equipment (UE) according to one embodiment of the present disclosure comprises: a transmission and reception device configured to transmit and receive signals with two or more transmission and reception points (TRPs); and at least one processor, wherein the at least one processor:

A method for transmitting a transmission configuration indicator (TCI) to a plurality of TRPs, the method comprising: receiving upper layer signaling including a first timing offset, a beam application time (BAT), and Transmission Configuration Indicator (TCI) type information; receiving indication information for a unified TCI for the two or more TRPs; communicating with the two or more TRPs based on the first timing offset and the unified TCI; receiving TCI state change indication information from one of the two or more TRPs; and in response to receiving the TCI state change indication information, determining a first slot for transmitting a hybrid automatic repeat request (HARQ) feedback over a Physical Uplink Control Channel (PUCCH) based on the first timing offset and the BAT; and causing the HARQ feedback for each of the two or more TRPs to be transmitted to the two or more TRPs over the first PUCCH in the determined first slot.

At least one processor of the above:

When the above TCI state change indication information is indicated by downlink control information (DCI), it can be determined whether the DCI includes a second timing offset; and if the second timing offset is included, a second slot for transmitting the HARQ feedback through the PUCCH is determined based on the second timing offset and the BAT; and further cause the HARQ feedback to be transmitted to the two or more TRPs in the determined second slot.

The second slot to transmit the HARQ feedback may be determined as a slot index calculated as the sum of a last slot index of a physical downlink shared channel (PDSCH) received from the two or more TRPs, a value set by the second timing offset, and an additional slot index value determined by the BAT value.

If the number of symbols indicated by the BAT is not equal to the number of symbols constituting one slot, the additional slot index value may be a value obtained by adding "1" to the largest integer among the values obtained by dividing the number of symbols indicated by the BAT by the number of symbols constituting one slot, and if the number of symbols indicated by the BAT is a multiple of N of the symbols constituting one slot (where N is a natural number), the additional slot value may be a value obtained by dividing the number of symbols indicated by the BAT by the number of symbols constituting one slot.

The first slot may be determined as a slot index calculated as the sum of a last slot index of a physical downlink shared channel (PDSCH) received from the two or more TRPs, a value set by the first timing offset, and an additional slot value determined by the BAT value.

If the number of symbols indicated by the BAT is not equal to the number of symbols constituting one slot, the additional slot index value may be a value obtained by adding "1" to the largest integer among the values obtained by dividing the number of symbols indicated by the BAT by the number of symbols constituting one slot, and if the number of symbols indicated by the BAT is a multiple of N of the symbols constituting one slot (where N is a natural number), the additional slot index value may be a value obtained by dividing the number of symbols indicated by the BAT by the number of symbols constituting one slot.

At least one processor of the above:

If the BAT is set to a value smaller than one slot, and the TCI state change indication information included in a single downlink control information (DCI) is set to transmit the HARQ feedback through one third PUCCH for the two or more TRPs, the method may further cause the TRPs for which the BAT is required among the two or more TRPs to be grouped; determine different third PUCCH resource indices for transmitting the HARQ feedback for each of the grouped TRPs; and transmit the HARQ feedback to the grouped TRPs through a third PUCCH resource indicated by the determined third PUCCH resource index.

The above HARQ feedback may include a TRP identifier (ID) for each of the grouped TRPs.

The grouped TRPs include a first TRP and a second TRP, and the third PUCCH for the first TRP includes a fourth PUCCH resource directly set by the first TRP, and a fifth PUCCH resource for the second TRP is allocated from a symbol after the BAT value when the BAT is required, and the fifth PUCCH resource can have the same format as the fourth PUCCH resource.

According to the present disclosure, a UE can generate HARQ-ACK information with one codebook to transmit a response to MAC-CE or DCI received in multiple TRPs, and transmit it to a base station (e.g., a TRP or panel) via a PUCCH. At this time, according to the present disclosure, when updating a TCI state, when using one DCI, resource setting considering a beam application time is possible based on the TCI state for each of the multiple TRPs. In addition, there is an advantage in that resource setting for multiple TRPs is possible considering the Bat of the UE for each TRP that may occur due to a change in the TCI state.

Figure 1 is a conceptual diagram illustrating a first embodiment of a communication system.

FIG. 2 is a block diagram illustrating a first embodiment of a communication node constituting a communication system.

FIG. 3 is a block diagram illustrating a first embodiment of communication nodes performing communication.

FIG. 4a is a block diagram illustrating a first embodiment of a transmission path.

FIG. 4b is a block diagram illustrating a first embodiment of a receiving path.

Figure 5 is a conceptual diagram illustrating a first embodiment of a system frame in a communication system.

Figure 6 is a conceptual diagram illustrating a first embodiment of a subframe in a communication system.

Figure 7 is a conceptual diagram illustrating a first embodiment of a slot in a communication system.

Figure 8 is a conceptual diagram illustrating a first embodiment of time-frequency resources in a communication system.

Figure 9 is a conceptual diagram explaining a case where beam application time (BAT) is applied.

Figure 10 is a conceptual diagram explaining a case where beam application time (BAT) is applied.

FIG. 11 is a flowchart illustrating a case where a UE transmits HQRQ feedback according to the first embodiment of the present disclosure.

FIG. 12 is a flowchart illustrating a case where a UE transmits HQRQ feedback according to the second embodiment of the present disclosure.

The present disclosure may have various modifications and various embodiments, and thus specific embodiments are illustrated and described in detail in the drawings. However, this is not intended to limit the present disclosure to specific embodiments, but should be understood to include all modifications, equivalents, and alternatives included in the spirit and technical scope of the present disclosure.

The terms first, second, etc. may be used to describe various components, but the components should not be limited by the terms. The terms are only used to distinguish one component from another. For example, without departing from the scope of the present disclosure, the first component could be referred to as the second component, and similarly, the second component could also be referred to as the first component. The term "and/or" can mean a combination of a plurality of related listed items or any one of a plurality of related listed items.

In the present disclosure, "at least one of A and B" can mean "at least one of A or B" or "at least one of combinations of one or more of A and B." Additionally, in the present disclosure, "at least one of A and B" can mean "at least one of A or B" or "at least one of combinations of one or more of A and B."

In the present disclosure, (re)transmitting can mean “transmitting”, “retransmitting”, or “transmitting and retransmitting”, (re)setting can mean “setting”, “resetting”, or “setting and resetting”, (re)connecting can mean “connecting”, “reconnecting”, or “connecting and reconnecting”, and (re)connecting can mean “connecting”, “reconnecting”, or “connecting and reconnecting”.

When it is said that a component is "connected" or "connected" to another component, it should be understood that it may be directly connected or connected to that other component, but that there may be other components in between. On the other hand, when it is said that a component is "directly connected" or "directly connected" to another component, it should be understood that there are no other components in between.

The terminology used in this disclosure is only used to describe specific embodiments and is not intended to be limiting of the present disclosure. The singular expression includes the plural expression unless the context clearly indicates otherwise. In this disclosure, it should be understood that the terms "comprises" or "has" and the like are intended to specify that a feature, number, step, operation, component, part or combination thereof described in the specification is present, but do not exclude in advance the possibility of the presence or addition of one or more other features, numbers, steps, operations, components, parts or combinations thereof.

Unless otherwise defined, all terms used herein, including technical or scientific terms, have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure belongs. Terms defined in commonly used dictionaries, such as those defined in common usage, should be interpreted as having a meaning consistent with the meaning they have in the context of the relevant art, and will not be interpreted in an idealized or overly formal sense unless expressly defined in this disclosure.

Hereinafter, with reference to the attached drawings, preferred embodiments of the present disclosure will be described in more detail. In order to facilitate an overall understanding in describing the present disclosure, the same reference numerals are used for the same components in the drawings, and redundant descriptions of the same components are omitted. In addition to the embodiments explicitly described in the present disclosure, operations according to combinations of embodiments, extensions of embodiments, and/or modifications of embodiments can be performed. The performance of some operations can be omitted, and the order of performing the operations can be changed.

In an embodiment, even if a method (e.g., transmitting or receiving a signal) performed by a first communication node among communication nodes is described, a second communication node corresponding thereto can perform a method (e.g., receiving or transmitting a signal) corresponding to the method performed by the first communication node. That is, if an operation of a UE (user equipment) is described, a base station corresponding thereto can perform an operation corresponding to the operation of the UE. Conversely, if an operation of a base station is described, a UE corresponding thereto can perform an operation corresponding to the operation of the base station.

The base station may be referred to as a NodeB, an evolved NodeB, a gNodeB (next generation node B), a gNB, a device, an apparatus, a node, a communication node, a BTS (base transceiver station), an RRH (radio remote head), a TRP (transmission reception point), a RU (radio unit), an RSU (road side unit), a radio transceiver, an access point, an access node, etc. The UE may be referred to as a terminal, a device, an apparatus, a node, a communication node, an end node, an access terminal, a mobile terminal, a station, a subscriber station, a mobile station, a portable subscriber station, an OBU (on-broad unit), etc.

In the present disclosure, signaling may be at least one of upper layer signaling, MAC signaling, or PHY (physical) signaling. A message used for upper layer signaling may be referred to as an "upper layer message" or an "upper layer signaling message". A message used for MAC signaling may be referred to as a "MAC message" or a "MAC signaling message". A message used for PHY signaling may be referred to as a "PHY message" or a "PHY signaling message". Upper layer signaling may refer to a transmission and reception operation of system information (e.g., a master information block (MIB), a system information block (SIB)) and/or an RRC message. MAC signaling may refer to a transmission and reception operation of a MAC control element (CE). PHY signaling may refer to a transmission and reception operation of control information (e.g., downlink control information (DCI), uplink control information (UCI), sidelink control information (SCI)).

In the present disclosure, "an operation (e.g., a transmission operation) is set" may mean that "setting information for the operation (e.g., an information element, a parameter)" and/or "information instructing performance of the operation" are signaled. "An information element (e.g., a parameter) is set" may mean that the information element is signaled. In the present disclosure, "a signal and/or a channel" may mean a signal, a channel, or "a signal and a channel," and a signal may be used to mean "a signal and/or a channel."

The communication network to which the embodiment is applied is not limited to what is described below, and the embodiment can be applied to various communication networks (e.g., 4G communication network, 5G communication network, and/or 6G communication network). Here, the communication network can be used in the same meaning as the communication system.

Figure 1 is a conceptual diagram illustrating a first embodiment of a communication system.

Referring to FIG. 1, the communication system (100) may include a plurality of communication nodes (110-1, 110-2, 110-3, 120-1, 120-2, 130-1, 130-2, 130-3, 130-4, 130-5, 130-6). In addition, the communication system (100) may further include a core network (e.g., a serving-gateway (S-GW), a packet data network (PDN)-gateway (P-GW), a mobility management entity (MME)). If the communication system (100) is a 5G communication system (e.g., a new radio (NR) system), the core network may include an access and mobility management function (AMF), a user plane function (UPF), a session management function (SMF), etc.

A plurality of communication nodes (110 to 130) can support a communication protocol specified in a 3rd generation partnership project (3GPP) standard (e.g., LTE communication protocol, LTE-A communication protocol, NR communication protocol, etc.). The plurality of communication nodes (110 to 130) may support CDMA (code division multiple access) technology, WCDMA (wideband CDMA) technology, TDMA (time division multiple access) technology, FDMA (frequency division multiple access) technology, OFDM (orthogonal frequency division multiplexing) technology, Filtered OFDM technology, CP (cyclic prefix)-OFDM technology, DFT-s-OFDM (discrete Fourier transform-spread-OFDM) technology, OFDMA (orthogonal frequency division multiple access) technology, SC (single carrier)-FDMA technology, NOMA (non-orthogonal multiple access) technology, GFDM (generalized frequency division multiplexing) technology, FBMC (filter bank multi-carrier) technology, UFMC (universal filtered multi-carrier) technology, SDMA (space division multiple access) technology, etc. Each of the plurality of communication nodes may have the following structure.

FIG. 2 is a block diagram illustrating a first embodiment of a communication node constituting a communication system.

Referring to FIG. 2, a communication node (200) may include at least one processor (210), a memory (220), and a transceiver device (230) that is connected to a network and performs communication. In addition, the communication node (200) may further include an input interface device (240), an output interface device (250), a storage device (260), etc. Each component included in the communication node (200) may be connected by a bus (270) and communicate with each other.

The processor (210) can execute a program command stored in at least one of the memory (220) and the storage device (260). The processor (210) may mean a central processing unit (CPU), a graphics processing unit (GPU), or a dedicated processor on which methods according to embodiments of the present disclosure are performed. Each of the memory (220) and the storage device (260) may be configured with at least one of a volatile storage medium and a nonvolatile storage medium. For example, the memory (220) may be configured with at least one of a read only memory (ROM) and a random access memory (RAM).

Referring again to FIG. 1, the communication system (100) may include a plurality of base stations (110-1, 110-2, 110-3, 120-1, 120-2) and a plurality of terminals (130-1, 130-2, 130-3, 130-4, 130-5, 130-6). Each of the first base station (110-1), the second base station (110-2), and the third base station (110-3) may form a macro cell. Each of the fourth base station (120-1) and the fifth base station (120-2) may form a small cell. The fourth base station (120-1), the third terminal (130-3), and the fourth terminal (130-4) may be within the cell coverage of the first base station (110-1). The second terminal (130-2), the fourth terminal (130-4), and the fifth terminal (130-5) may be within the cell coverage of the second base station (110-2). The fifth base station (120-2), the fourth terminal (130-4), the fifth terminal (130-5), and the sixth terminal (130-6) may be within the cell coverage of the third base station (110-3). The first terminal (130-1) may be within the cell coverage of the fourth base station (120-1). The sixth terminal (130-6) may be within the cell coverage of the fifth base station (120-2).

Here, each of the plurality of base stations (110-1, 110-2, 110-3, 120-1, 120-2) may be referred to as a NodeB (NB), an evolved NodeB (eNB), a gNB, an advanced base station (ABS), a high reliability-base station (HR-BS), a base transceiver station (BTS), a radio base station, a radio transceiver, an access point, an access node, a radio access station (RAS), a mobile multihop relay-base station (MMR-BS), a relay station (RS), an advanced relay station (ARS), a high reliability-relay station (HR-RS), a home NodeB (HNB), a home eNodeB (HeNB), a road side unit (RSU), a radio remote head (RRH), a transmission point (TP), a transmission and reception point (TRP), etc.

Each of the plurality of terminals (130-1, 130-2, 130-3, 130-4, 130-5, 130-6) may be referred to as a user equipment (UE), terminal equipment (TE), advanced mobile station (AMS), high reliability-mobile station (HR-MS), terminal, access terminal, mobile terminal, station, subscriber station, mobile station, portable subscriber station, node, device, OBU (on board unit), etc.

Meanwhile, each of the plurality of base stations (110-1, 110-2, 110-3, 120-1, 120-2) may operate in a different frequency band or may operate in the same frequency band. Each of the plurality of base stations (110-1, 110-2, 110-3, 120-1, 120-2) may be connected to each other via an ideal backhaul link or a non-ideal backhaul link, and may exchange information with each other via the ideal backhaul link or the non-ideal backhaul link. Each of the plurality of base stations (110-1, 110-2, 110-3, 120-1, 120-2) may be connected to a core network via an ideal backhaul link or a non-ideal backhaul link. Each of the plurality of base stations (110-1, 110-2, 110-3, 120-1, 120-2) can transmit a signal received from the core network to the corresponding terminal (130-1, 130-2, 130-3, 130-4, 130-5, 130-6), and can transmit a signal received from the corresponding terminal (130-1, 130-2, 130-3, 130-4, 130-5, 130-6) to the core network.

In addition, each of the plurality of base stations (110-1, 110-2, 110-3, 120-1, 120-2) can support MIMO transmission (e.g., single user (SU)-MIMO, multi user (MU)-MIMO, massive MIMO, etc.), coordinated multipoint (CoMP) transmission, carrier aggregation (CA) transmission, transmission in an unlicensed band, sidelink communication (e.g., device to device communication (D2D), proximity services (ProSe)), Internet of Things (IoT) communication, dual connectivity (DC), etc. Here, each of the plurality of terminals (130-1, 130-2, 130-3, 130-4, 130-5, 130-6) can perform an operation corresponding to the base station (110-1, 110-2, 110-3, 120-1, 120-2) and an operation supported by the base station (110-1, 110-2, 110-3, 120-1, 120-2). For example, the second base station (110-2) can transmit a signal to the fourth terminal (130-4) based on the SU-MIMO scheme, and the fourth terminal (130-4) can receive a signal from the second base station (110-2) by the SU-MIMO scheme. Alternatively, the second base station (110-2) can transmit signals to the fourth terminal (130-4) and the fifth terminal (130-5) based on the MU-MIMO method, and each of the fourth terminal (130-4) and the fifth terminal (130-5) can receive signals from the second base station (110-2) by the MU-MIMO method.

Each of the first base station (110-1), the second base station (110-2), and the third base station (110-3) can transmit a signal to the fourth terminal (130-4) based on the CoMP scheme, and the fourth terminal (130-4) can receive a signal from the first base station (110-1), the second base station (110-2), and the third base station (110-3) based on the CoMP scheme. Each of the plurality of base stations (110-1, 110-2, 110-3, 120-1, 120-2) can transmit and receive a signal with terminals (130-1, 130-2, 130-3, 130-4, 130-5, 130-6) within its cell coverage based on the CA scheme. Each of the first base station (110-1), the second base station (110-2), and the third base station (110-3) can control sidelink communication between the fourth terminal (130-4) and the fifth terminal (130-5), and each of the fourth terminal (130-4) and the fifth terminal (130-5) can perform sidelink communication under the control of the second base station (110-2) and the third base station (110-3).

Meanwhile, communication nodes performing communication in a communication network can be configured as follows. The communication node illustrated in Fig. 3 may be a specific embodiment of the communication node illustrated in Fig. 2.

FIG. 3 is a block diagram illustrating a first embodiment of communication nodes performing communication.

Referring to FIG. 3, each of the first communication node (300a) and the second communication node (300b) may be a base station or a UE. The first communication node (300a) may transmit a signal to the second communication node (300b). The transmission processor (311) included in the first communication node (300a) may receive data (e.g., a data unit) from a data source (310). The transmission processor (311) may receive control information from the controller (316). The control information may include at least one of system information, RRC configuration information (e.g., information configured by RRC signaling), MAC control information (e.g., MAC CE), or PHY control information (e.g., DCI, SCI).

The transmitting processor (311) can perform a processing operation (e.g., an encoding operation, a symbol mapping operation, etc.) on data to generate data symbol(s). The transmitting processor (311) can perform a processing operation (e.g., an encoding operation, a symbol mapping operation, etc.) on control information to generate control symbol(s). In addition, the transmitting processor (311) can generate synchronization/reference symbol(s) for a synchronization signal and/or a reference signal.

The Tx MIMO processor (312) can perform spatial processing operations (e.g., a precoding operation) on data symbol(s), control symbol(s), and/or synchronization/reference symbol(s). An output (e.g., a symbol stream) of the Tx MIMO processor (312) can be provided to modulators (MODs) included in the transceivers (313a to 313t). The modulators (MODs) can perform processing operations on the symbol streams to generate modulation symbols and perform additional processing operations (e.g., an analog conversion operation, an amplification operation, a filtering operation, an upconversion operation) on the modulation symbols to generate signals. The signals generated by the modulators (MODs) of the transceivers (313a to 313t) can be transmitted via the antennas (314a to 314t).

The signals transmitted by the first communication node (300a) may be received by the antennas (364a to 364r) of the second communication node (300b). The signals received by the antennas (364a to 364r) may be provided to the demodulators (DEMODs) included in the transceivers (363a to 363r). The demodulator (DEMOD) may perform a processing operation (e.g., a filtering operation, an amplification operation, a down-conversion operation, a digital conversion operation) on the signal to obtain samples. The demodulator (DEMOD) may perform an additional processing operation on the samples to obtain symbols. The MIMO detector (362) may perform a MIMO detection operation on the symbols. The receiving processor (361) may perform a processing operation (e.g., a deinterleaving operation, a decoding operation) on the symbols. The output of the receiving processor (361) may be provided to a data sink (360) and a controller (366). For example, data may be provided to the data sink (360) and control information may be provided to the controller (366).

Meanwhile, the second communication node (300b) can transmit a signal to the first communication node (300a). The transmitting processor (368) included in the second communication node (300b) can receive data (e.g., data units) from a data source (367) and perform a processing operation on the data to generate data symbol(s). The transmitting processor (368) can receive control information from the controller (366) and perform a processing operation on the control information to generate control symbol(s). In addition, the transmitting processor (368) can perform a processing operation on a reference signal to generate reference symbol(s).

The Tx MIMO processor (369) can perform spatial processing operations (e.g., precoding operations) on data symbol(s), control symbol(s), and/or reference symbol(s). An output (e.g., a symbol stream) of the Tx MIMO processor (369) can be provided to modulators (MODs) included in the transceivers (363a to 363t). The modulators (MODs) can perform processing operations on the symbol streams to generate modulation symbols and can perform additional processing operations (e.g., an analog conversion operation, an amplification operation, a filtering operation, an upconversion operation) on the modulation symbols to generate signals. The signals generated by the modulators (MODs) of the transceivers (363a to 363t) can be transmitted via the antennas (364a to 364t).

The signals transmitted by the second communication node (300b) may be received by the antennas (314a to 314r) of the first communication node (300a). The signals received by the antennas (314a to 314r) may be provided to the demodulators (DEMODs) included in the transceivers (313a to 313r). The demodulator (DEMOD) may perform a processing operation (e.g., a filtering operation, an amplification operation, a down-conversion operation, a digital conversion operation) on the signal to obtain samples. The demodulator (DEMOD) may perform an additional processing operation on the samples to obtain symbols. The MIMO detector (320) may perform a MIMO detection operation on the symbols. The receiving processor (319) may perform a processing operation (e.g., a deinterleaving operation, a decoding operation) on the symbols. The output of the receiving processor (319) may be provided to a data sink (318) and a controller (316). For example, data may be provided to the data sink (318) and control information may be provided to the controller (316).

Memories (315 and 365) can store data, control information, and/or program code. Scheduler (317) can perform scheduling operations for communications. Processors (311, 312, 319, 361, 368, 369) and controllers (316, 366) illustrated in FIG. 3 may be processors (210) illustrated in FIG. 2 and may be used to perform the methods described in the present disclosure.

FIG. 4a is a block diagram illustrating a first embodiment of a transmission path, and FIG. 4b is a block diagram illustrating a first embodiment of a reception path.

Referring to FIGS. 4A and 4B, a transmission path (410) may be implemented in a communication node that transmits a signal, and a reception path (420) may be implemented in a communication node that receives a signal. The transmission path (410) may include a channel coding and modulation block (411), an S-to-P (serial-to-parallel) block (512), an N IFFT (Inverse Fast Fourier Transform) block (413), a P-to-S (parallel-to-serial) block (414), a CP (cyclic prefix) addition block (415), and an UC (up-converter) (UC) (416). The receiving path (420) may include a DC (down-converter) (421), a CP removal block (422), an S-to-P block (423), an N FFT block (424), a P-to-S block (425), and a channel decoding and demodulation block (426). Here, N may be a natural number.

In the transmission path (410), information bits may be input to a channel coding and modulation block (411). The channel coding and modulation block (411) may perform a coding operation (e.g., a low-density parity check (LDPC) coding operation, a polar coding operation, etc.) and a modulation operation (e.g., a quadrature phase shift keying (QPSK), a quadrature amplitude modulation (QAM), etc.) on the information bits. An output of the channel coding and modulation block (411) may be a sequence of modulation symbols.

The S-to-P block (412) can convert modulation symbols in the frequency domain into parallel symbol streams to generate N parallel symbol streams. N can be an IFFT size or an FFT size. The N IFFT block (413) can perform an IFFT operation on the N parallel symbol streams to generate signals in the time domain. The P-to-S block (414) can convert the output (e.g., parallel signals) of the N IFFT block (413) into a serial signal to generate a serial signal.

The CP addition block (415) can insert a CP into a signal. The UC (416) can up-convert the frequency of the output of the CP addition block (415) to an RF (radio frequency) frequency. Additionally, the output of the CP addition block (415) can be filtered at baseband before up-conversion.

A signal transmitted from the transmission path (410) may be input to the reception path (420). An operation in the reception path (420) may be an inverse operation of the operation in the transmission path (410). The DC (421) may down-convert the frequency of the received signal to a frequency of the baseband. The CP removal block (422) may remove a CP from the signal. An output of the CP removal block (422) may be a serial signal. The S-to-P block (423) may convert the serial signal into parallel signals. The N FFT block (424) may perform an FFT algorithm to generate N parallel signals. The P-to-S block (425) may convert the parallel signals into a sequence of modulation symbols. The channel decoding and demodulation block (426) may perform a demodulation operation on the modulation symbols and perform a decoding operation on the result of the demodulation operation to restore data.

In FIGS. 4A and 4B, Discrete Fourier Transform (DFT) and Inverse DFT (IDFT) can be used instead of FFT and IFFT. Each of the blocks (e.g., components) in FIGS. 4A and 4B can be implemented by at least one of hardware, software, or firmware. For example, some of the blocks in FIGS. 4A and 4B can be implemented by software, and the remaining blocks can be implemented by hardware or a “combination of hardware and software.” In FIGS. 4A and 4B, one block can be subdivided into multiple blocks, multiple blocks can be integrated into one block, some blocks can be omitted, and blocks supporting other functions can be added.

Figure 5 is a conceptual diagram illustrating a first embodiment of a system frame in a communication system.

Referring to FIG. 5, time resources in a communication system can be divided into frame units. For example, system frames can be set sequentially in the time domain of the communication system. The length of a system frame can be 10 ms (milliseconds). A system frame number (SFN) can be set from #0 to #1023. In this case, 1024 system frames can be repeated in the time domain of the communication system. For example, the SFN of a system frame after system frame #1023 can be #0.

A system frame may include two half frames. A half frame may be 5 ms long. A half frame located at the beginning of the system frame may be referred to as "half frame #0", and a half frame located at the end of the system frame may be referred to as "half frame #1". A system frame may include 10 subframes. A subframe may be 1 ms long. The 10 subframes within a system frame may be referred to as "subframe #0-9".

Figure 6 is a conceptual diagram illustrating a first embodiment of a subframe in a communication system.

Referring to FIG. 6, one subframe may include n slots, where n may be a natural number. Accordingly, one subframe may be composed of one or more slots.

Figure 7 is a conceptual diagram illustrating a first embodiment of a slot in a communication system.

Referring to FIG. 7, one slot may include one or more symbols. One slot illustrated in FIG. 7 may include 14 symbols. The length of a slot may vary depending on the number of symbols included in the slot and the length of the symbols. Alternatively, the length of a slot may vary depending on the numerology.

In a communication system, a numerology applied to a physical signal and a channel can be variable. The numerology can be variable to meet various technical requirements of the communication system. In a communication system to which CP (cyclic prefix)-based OFDM waveform technology is applied, the numerology can include a subcarrier spacing and a CP length (or a CP type). Table 1 may be a first embodiment of a method for configuring a numerology for a CP-OFDM-based communication system. At least some of the numerologies in Table 1 may be supported depending on a frequency band in which the communication system operates. In addition, the communication system may additionally support numerology(s) not listed in Table 1.

Subcarrier spacing	15 kHz	30 kHz	60 kHz	120 kHz	240 kHz	480 kHz
OFDM Symbol length [μs]	66.7	33.3	16.7	8.3	4.2	2.1
CP length [μs]	4.76	2.38	1.19	0.60	0.30	0.15
Number of OFDM symbols in 1ms	14	28	56	112	224	448

When the subcarrier spacing is 15 kHz (e.g., μ=0), the slot length can be 1 ms. In this case, one system frame can contain 10 slots. When the subcarrier spacing is 30 kHz (e.g., μ=1), the slot length can be 0.5 ms. In this case, one system frame can contain 20 slots.

When the subcarrier spacing is 60 kHz (e.g., μ=2), the length of a slot can be 0.25 ms. In this case, one system frame can contain 40 slots. When the subcarrier spacing is 120 kHz (e.g., μ=3), the length of a slot can be 0.125 ms. In this case, one system frame can contain 80 slots. When the subcarrier spacing is 240 kHz (e.g., μ=4), the length of a slot can be 0.0625 ms. In this case, one system frame can contain 160 slots.

A symbol may be configured as a downlink (DL) symbol, a flexible (FL) symbol, or an uplink (UL) symbol. A slot composed of only DL symbols may be referred to as a "DL slot," a slot composed of only FL symbols may be referred to as a "FL slot," and a slot composed of only UL symbols may be referred to as a "UL slot."

The slot format can be semi-statically set by higher layer signaling (e.g., RRC signaling). Information indicating the semi-static slot format can be included in system information, and the semi-static slot format can be set cell-specifically. In addition, the semi-static slot format can be additionally set for each terminal by terminal-specific higher layer signaling (e.g., RRC signaling). A flexible symbol of a slot format set cell-specifically can be overridden with a downlink symbol or an uplink symbol by terminal-specific higher layer signaling. In addition, the slot format can be dynamically indicated by physical layer signaling (e.g., a slot format indicator (SFI) included in DCI). A semi-statically set slot format can be overridden by a dynamically indicated slot format. For example, a flexible symbol set semi-statically can be overridden with a downlink symbol or an uplink symbol by the SFI.

The reference signal may be a channel state information-reference signal (CSI-RS), a sounding reference signal (SRS), a demodulation-reference signal (DM-RS), a phase tracking-reference signal (PT-RS), etc. The channel may be a physical broadcast channel (PBCH), a physical downlink control channel (PDCCH), a physical downlink shared channel (PDSCH), a physical uplink control channel (PUCCH), a physical uplink shared channel (PUSCH), a physical sidelink control channel (PSCCH), a physical sidelink shared channel (PSSCH), etc. In the present disclosure, a control channel may mean a PDCCH, a PUCCH, or a PSCCH, and a data channel may mean a PDSCH, a PUSCH, or a PSSCH.

Figure 8 is a conceptual diagram illustrating a first embodiment of time-frequency resources in a communication system.

Referring to FIG. 8, a resource composed of one symbol (e.g., OFDM symbol) in the time domain and one subcarrier in the frequency domain may be defined as a "RE (resource element)". Resources composed of one OFDM symbol in the time domain and K subcarriers in the frequency domain may be defined as a "REG (resource element group)". A REG may include K REs. A REG may be used as a basic unit of resource allocation in the frequency domain. K may be a natural number. For example, K may be 12. N may be a natural number. In the slot illustrated in FIG. 7, N may be 14. The N OFDM symbols may be used as a basic unit of resource allocation in the time domain.

In the present disclosure, RB may mean CRB (common RB). Alternatively, RB may mean PRB or VRB (virtual RB). In a communication system, CRB may mean RB constituting a set of consecutive RBs (e.g., common RB grid) based on a reference frequency (e.g., point A). Carriers and/or bandwidth portions may be arranged on the common RB grid. That is, the carrier and/or bandwidth portions may be composed of CRB(s). RBs or CRBs constituting the bandwidth portions may be referred to as PRBs, and a CRB index within the bandwidth portion may be appropriately converted to a PRB index.

Downlink data can be transmitted via PDSCH. The base station can transmit configuration information (e.g., scheduling information) of the PDSCH to the terminal via PDCCH. The terminal can obtain the configuration information of the PDSCH by receiving the PDCCH (e.g., downlink control information (DCI)). For example, the configuration information of the PDSCH can include an MCS (modulation coding scheme) used for transmitting and receiving the PDSCH, time resource information of the PDSCH, frequency resource information of the PDSCH, feedback resource information for the PDSCH, etc. The PDSCH may refer to a radio resource through which downlink data is transmitted and received. Alternatively, the PDSCH may refer to the downlink data itself. The PDCCH may refer to a radio resource through which downlink control information (e.g., DCI) is transmitted and received. Alternatively, the PDCCH may refer to the downlink control information itself.

The terminal can perform a monitoring operation for the PDCCH in order to receive the PDSCH transmitted from the base station. The base station can inform the terminal of the configuration information for the monitoring operation of the PDCCH using a higher layer message (e.g., an RRC (radio resource control) message). The configuration information for the monitoring operation of the PDCCH can include CORESET (control resource set) information and search space information.

CORESET information may include PDCCH DMRS (demodulation reference signal) information, PDCCH precoding information, PDCCH occasion information, etc. The PDCCH DMRS may be a DMRS used to demodulate the PDCCH. The PDCCH occasion may be a region in which a PDCCH can exist. That is, the PDCCH occasion may be a region in which DCI can be transmitted. The PDCCH occasion may be referred to as a PDCCH candidate. The PDCCH occasion information may include time resource information and frequency resource information of the PDCCH occasion. The length of the PDCCH occasion in the time domain may be indicated in symbol units. The size of the PDCCH occasion in the frequency domain may be indicated in RB units (for example, in PRB (physical resource block) units or CRB (common resource block) units).

The search space information may include a CORESET ID (identifier) associated with the search space, a period of PDCCH monitoring, and/or an offset. Each of the period and offset of PDCCH monitoring may be indicated in slot units. In addition, the search space information may further include an index of a symbol at which a PDCCH monitoring operation starts.

A base station can set a BWP (bandwidth part) for downlink communication. The BWP can be set differently for each terminal. The base station can inform the terminal of the configuration information of the BWP using upper layer signaling. The upper layer signaling can mean "transmission operation of system information" and/or "transmission operation of RRC (radio resource control) message." The number of BWPs set for one terminal can be 1 or more. The terminal can receive configuration information of the BWP from the base station, and can identify the BWP(s) set by the base station based on the configuration information of the BWP. When a plurality of BWPs are set for downlink communication, the base station can activate one or more BWPs among the plurality of BWPs. The base station can transmit the configuration information of the activated BWP(s) to the terminal using at least one of upper layer signaling, MAC (medium access control) CE (control element), or DCI. The base station can perform downlink communication using the activated BWP(s). The terminal can identify the activated BWP(s) by receiving configuration information of the activated BWP(s) from the base station, and perform a downlink reception operation in the activated BWP(s).

Meanwhile, in order to ensure reliability of downlink and improve transmission rate in cell-edge area, 5G NR can use physical channels separately or sharedly for each transmission reception point (TRP) or panel. Communication using this method can be representative target use cases such as URLLC and eMBB.

3GPP, which is standardizing wireless communications, discussed how to support multiple-TRP (MTRP) in the Rel-17 standard, and in particular, conducted technical discussions and standardization on PDCCH enhancement to support MTRP. In order to ensure the reliability of PDCCH in 5G NR for the MTRP environment, it can be transmitted in different ways depending on the deployment. Deployment scenarios for ensuring the reliability of PDCCH can be largely divided into two methods: single-frequency network (SFN) and non single-frequency network (non-SFN).

In case of SFN deployment, the same PDCCH transmission is considered by utilizing the same time, frequency and space resources in different TRPs or different panels. In other words, PDCCHs transmitted in all TRPs transmit PDCCHs using the same DMRS configuration, position and sequence. At this time, the Transmission Configuration Indicator (TCI) settings for TRP(s) or panel(s) from the receiving perspective can be implicitly set differently. In other words, the standard does not support an explicit TCI setting and/or indication method for TRP(s) or panel(s) from the receiving perspective. Since the explicit TCI setting and/or indication method is not supported, MTRP has multiple TCI states in CORESET. Therefore, when MTRPs transmit PDCCH, there is a constraint on the synchronization with the ideal backhaul or near-ideal backhaul between TRPs.

For Non-SFN, PDCCH transmission methods can be divided into the following two transmission methods.

First, there may be a way in which the PDCCHs generated fully in each of the TRPs are multiplexed and transmitted in time and/or frequency axes within the same or different CORESETs. Here, the way in which the PDCCHs are multiplexed and transmitted in time and/or frequency axes may be, for example, mTRP-based PDCCH repetition transmission.

Second, there may be a method of splitting bits equal to the number of encoded bits transmitted through one PDCCH into TRPs and transmitting them through different PDCCH candidates. Here, the method of transmitting through different PDCCH candidates may mean, for example, single TRP (sTRP)-based PDCCH transmission.

In the first case, PDCCHs are repeatedly generated as many times as the number of TRPs, and PDCCHs are transmitted from the same search space index within different search space sets having the same number of PDCCH candidates. At this time, the search space sets may exist within the same CORESET or may exist within different CORESETs.

According to the 3GPP standard, only one TCI state can be associated per a single CORESET, so if PDCCHs are transmitted in different search spaces within the same CORESET, only one TCI state of the two PDCCHs can be indicated and/or set. Therefore, at a given point in time, a UE can receive only one TCI state for one TRP.

On the other hand, when PDCCHs are transmitted in the same search space index within different CORESETs, the terminal can implicitly expect reception from a single TRP or reception from multiple TRPs, depending on the number of TCI states indicated and/or set.

The second method is to divide a single PDCCH into the number of TRPs and transmit the PDCCH on different PDCCH candidates. In other words, the aggregation level and the combined aggregation level are the same. The second method can also be assigned to different CORESETs, and since the final distributed PDCCH is the same as the payload of the PDCCH transmitted in the sTRP after combining, it has an advantage over the first iteration method in terms of decoding complexity.

In 3GPP Rel-18, it was decided to extend the unified TCI framework designed for sTRP, which was designed in 3GPP Rel-17, to the mTRP system described above. Therefore, it is time for a detailed discussion on this. In this disclosure, we will explain the configuration and transmission method of PUCCH when extending the unified TCI framework for existing sTPR to mTRP.

In 3GPP Rel-17, there was a discussion about the time at which the change is applied when there is a change in the TCI status on the user equipment (UE) side. This is called the 'beam application time'. In the following disclosure, the beam application time will be abbreviated as 'BAT'.

For BAT, it is set in the upper layer and is defined in bold letters in Table 2 below in the PDSCH-Config Information Element (IE) used to set UE specific PDSCH parameters.

PDSCH-Config ::= SEQUENCE { dataScramblingIdentityPDSCH INTEGER (0..1023) OPTIONAL, -- Need S dmrs-DownlinkForPDSCH-MappingTypeA SetupRelease { DMRS-DownlinkConfig } OPTIONAL, -- Need M dmrs-DownlinkForPDSCH-MappingTypeB SetupRelease { DMRS-DownlinkConfig } OPTIONAL, -- Need M … beamAppTime-r17 ENUMERATED {n1, n2, n4, n7, n14, n28, n42, n56, n70, n84, n98, n112, n224, n336, spare2, …

Hereinafter, the BAT illustrated in Table 2 above is described. BAT (beamAppTime) indicates the first slot to which the integrated TCI specified by the DCI specified in Section 5.1.5 of the 3GPP TS 38.214 document is applied. The value of n1 means 1 symbol, n2 means 2 symbols, etc. The first slot is the minimum Y symbol indicated by the BAT parameter after the last symbol of the joint or separate DL/UL beam indication confirmation. The same value shall be configured for all serving cells in any one of the U-TCI-UpdateListN configured in IE CellGroupConfig based on the minimum SCS of the active BWP.

The BAT indicates and/or sets the same value as cell common at the base station based on the capability reported from the UE. In addition, the application time may have problems such as errors depending on the unit time level. The errors depending on the unit time may include, for example, data loss due to the quantization level. Therefore, the minimum unit may be determined based on the subcarrier spacing (SCS), and the SCS of the smallest cell in the activated serving cells or deactivated serving cells through the MAC-CE may be commonly applied to all the activated serving cells or deactivated serving cells.

Figure 9 is a conceptual diagram explaining a case where beam application time (BAT) is applied.

Referring to FIG. 9, it is illustrated that the base station (910) is assigned different reference codes, 910a, 910b, and 910c, as time passes, so that it can be identified that it is a base station at different times. In addition, it is illustrated that the UE (920) is also assigned different reference codes, 920a, 920b, and 920c, as time passes, so that it can be identified that it is a UE at different times.

The first time point illustrated in FIG. 9 may be a case of communication between a UE (920a) and a base station (910a). At this time, it is assumed that the UE (920a) transmits data to the base station (910a) through an uplink beam (931) for uplink, for example, PUSCH transmission. In other words, at a previous time point not illustrated in FIG. 9, the base station may have instructed and/or set the same beam for the downlink (DL) channel and the uplink (UL) channel in a separate TCI state type to the UE. Accordingly, the uplink beam (931) through which the UE (920a) transmits data to the base station (910a) may be a beam indicated by the previously separated TCI state type by the base station. Here, the same beam may be, for example, a beam using a QCL/spatial filter.

Thereafter, while the UE (920a) transmits data to the base station (910a) through the uplink beam (931), at a certain point in time, the base station (910b) may transmit TCI indication information to the UE (920b) through a downlink control channel, for example, a PDCCH. As described above, it can be confirmed through the reference symbol that the point in time when the base station (910b) transmits the PDCCH to the UE (920b) is after the point in time when the UE (920a) transmits the PUSCH to the base station (910a). At this time, the TCI indication information included in the PDCCH may be transmitted through, for example, downlink control information (DCI). If the TCI indication information indicated by the DCI may indicate (or set) a unified TCI state.

To explain this again in chronological order, at a point in time prior to the time illustrated in FIG. 9, the base station may be in a state in which it has instructed the UE to a separate TCI type, and during communication between the base station and the UE, the base station may again be in a state instructing (or setting) the integrated TCI state.

Accordingly, the UE (920c) may need to reconfigure the beam based on the TCI state integrated with the base station (910c). In other words, the UE (920c) may need to change the previously used uplink beam (931) to a new uplink beam (932) based on the integrated TCI state. This may be the case where the change of the uplink beam is instructed by the integrated TCI state. Accordingly, the UE needs to set different spatial relation filter information than before through an uplink control channel, for example, PUCCH, and transmit it to the base station (910c). At this time, from the perspective of the UE (920c), the previous spatial filter needs to be changed to a new spatial filter and the PUCCH needs to be transmitted, so an additional time called BAT may be required. In FIG. 9, the additional required time, BAT, is exemplified by reference numeral 950.

Just as a UE (920c) requires BAT to transmit a PUCCH by applying a new spatial filter, when a TCI state change is instructed, BAT is required for DL channels as well as UL channels based on the instructed TCI state from the instructed time. In other words, BAT can be applied.

BAT is a different value from the radio frequency (RF) signal retuning time due to the change in frequency band discussed in the E-UTRAN New Radio - Dual Connectivity (ENDC) method between the 4G LTE network based on non-stand alone and the 5G New Radio. In addition, BAT has a different value from the RF retuning time due to the change in frequency band discussed in the supplementary uplink (SUL) as well as the uplink carrier aggregation (CA) method.

In the current 3GPP Rel-18, the indication of the integrated TCI state for mTRP can be indicated or set through one DCI (s-DCI) or two or more DCIs (m-DCI). In this case, when indicating the integrated TCI state based on one DCI (s-DCI), it is agreed to use DCI format 1_1 or DCI format 1_2.

On the other hand, when indicating an integrated TCI state based on two or more DCIs (m-DCIs), resource configuration is performed independently for each TRP. Therefore, it can be implemented by considering the corresponding BAT and configuring resources for the downlink (DL) channel and/or uplink (UL) channel according to the update of the state for each TRP.

In other words, in the case of one DCI (s-DCI), the basic configuration is based on resource configuration for DL channels and/or UL channels targeting multiple TRPs through one DCI. However, in the current 3GPP standard, in the case of the uplink channel for HARQ (PUCCH for HARQ), it can be seen that parameters related to transmission resources are indicated/configured to the UE as common values regardless of the TRP. Here, in the case of the uplink channel (PUCCH for HARQ), the parameters related to transmission resources may mean a PUCCH resource indicator and/or a PDSCH-to-HARQ_feedback timing indicator.

The UE can generate HARQ-ACK information with a single codebook in response to MAC-CE and/or DCI transmitted in multiple TRPs and transmit it to the base station via PUCCH. However, in the case of PUCCH resources required in response to TCI status update, a single timing value is set through a single DCI format for mTRP based on a single DCI (s-DCI) in the current 3GPP standard. Therefore, if the status changes of each TRP are different, the timing can only be set based on a single TRP. Let's examine this with reference to Fig. 10 below.

Figure 10 is a conceptual diagram explaining a case where beam application time (BAT) is applied.

Referring to Fig. 10, the horizontal axis represents time. This is an example of a situation in which a UE (1020) communicates with a first TRP (1011) and a second TRP (1012) at a specific point in time. At this time, it is assumed that the communication channel is an uplink channel, for example, PUSCH. In addition, in order to distinguish the channel between the first TRP (1011) and the second TRP (1012) according to time, the earlier point in time is illustrated as the first TRP (1011a) and the second TRP (1012a), and the later point in time is illustrated as the TRP (1011b) and the second TRP (1012b).

At an earlier point in time, the UE (1020) may transmit the PUSCH to the first TRP (1011a) using the first uplink beam (1031a) and transmit the PUSCH to the second TRP (1012a) using the second uplink beam (1032a).

At this time, let us assume that a TCI indication is transmitted from the first TRP (1011a) to the UE (1020) at time T11. Accordingly, the UE (1020) must change the uplink beam to the first TRP (1011a) and the second TRP (1012a). Therefore, the UE (1020) can transmit a PUCCH to the first TRP (1011b) through the uplink beam (1031b) after a time gap of a timing offset (1041). However, since the UE (1020) has a single timing value set through a single DCI format, in changing the second uplink beam (1032a) to the third uplink beam (1032b) to the second TRP (1012b), an additional time interval of a timing gap for beam application (1042) is required.

In other words, UE (1020) must perform TRP-specific responses at different time intervals due to BAT. However, according to the current standard, only one resource setting at the same time interval is possible based on one DCI (s-DCI). Therefore, when a beam change occurs as illustrated in FIG. 10, communication with the second TRP (1012) may not be possible.

Therefore, in this disclosure, we will describe a method for providing a PUCCH resource allocation scheme suitable for an mTRP environment when extending the integrated TCI state framework in an mTRP environment. In addition, the method described in this disclosure can be extended and applied to a downlink channel and/or an uplink channel based on the following description.

[Example 1: Slot-by-slot timing setting for HARQ-ACK considering beam application time]

In the following, we will describe the slot-by-slot timing setting for HARQ-ACK considering beam application time (BAT). It should be noted that the slot-by-slot timing for HARQ-ACK considering BAT described below can be applied to downlink channels and/or uplink channels.

An indication for the integrated TCI can be established via DCI or MAC-CE as described above. In the case of direct indication to the UE via MAC-CE, it can be a case where a single TCI codepoint or TCI state(s) for single or multiple TRPs for that TCI codepoint are conveyed.

In general, a base station (or TRP) transmits a 'TCI code point list' for code points to the UE via MAC-CE, and can then dynamically indicate one of the code point(s) included in the TCI code point list via DCI. On the other hand, direct indication via MAC-CE means not transmitting the TCI code point list to the UE, but rather transmitting an index or status corresponding to a single code point to the UE. Here, a single code point can mean one TCI set per TRP.

For example, if the integrated TCI state type is 'separate', there can be at most 2 states per TRP, and if it is 'joint', there can be at most 1 state. Depending on the number of TRPs, the number of states for each type can be at most N times. More specifically, in case of 2 TRPs and the 'separate' type, since there are 2 states for each TRP, it can mean that at most 4 states are linked to one code point. In other words, if directly instructed with MAC-CE, information of each state can be transmitted to the UE, or only the index value can be transmitted to the UE.

Ultimately, the instruction information for the integrated TCI can be conveyed to the UE via DCI or MAC-CE.

Typically, time resource information for a response to a PDSCH or PDCCH is transmitted from a base station to a UE via slot offset information, which may be configured via DCI or configured to use a pre-fixed value via RRC. Here, the response to a PDSCH or PDCCH may be, for example, a PUCCH for HARQ, and the slot offset information may be, for example, a PDSCH-to-HARQ_feedback timing indicator.

Depending on the presence or absence of the corresponding slot offset information in the DCI and depending on which channel the response is for, the transmittable slot of the PUCCH for HARQ may vary. For example, if the timing indicator does not exist in the DCI, the timing offset value preset by the RRC signaling is 'k', and the last slot of the PDSCH is 'n', the slot of the PUCCH can be the 'n+k' slot of the PUCCH for the HARQ feedback.

As another example, if a timing indicator is set in the DCI and its value is 'l', the PUCCH for HARQ feedback can be 'n+l' slots.

As another example, if a response to PDCCH is required, the slot for the response can also be 'm+k' or 'm+l'. Here, m can mean a slot in which PDCCH is transmitted. Here, 'k' and 'l' can mean values preset by RRC or values determined by timing instructions present in DCI, respectively.

Meanwhile, if the TCI state that has already been set as described above is changed, the UE requires time for beam formation (e.g., BAT). BAT can be set in advance by RRC signaling, and BAT can be set in symbol units, from a minimum of 1 symbol to a maximum of 336 symbols.

Considering BAT, the transmittable slots of PUCCH for HARQ described above, 'n+l' or 'n+k', may not be valid depending on the number of symbols of BAT. Therefore, this disclosure proposes a method for defining slots of PUCCH for HARQ feedback considering BAT.

Let's assume that the number of BAT symbols preset by the base station to the UE by RRC signaling is set to 'o' symbols. And let's assume that the number of symbols existing in one slot is 'p'. The above assumption and the value of 'n+l' or 'n+k', which is the transmittable slot of PUCCH for HARQ described above, may vary depending on whether BAT is required. For example, if BAT is required, the transmittable slot of PUCCH for HARQ may be 'n+l+q' or 'n+k+q'. Here, 'q' may be a value satisfying the following mathematical expression 1.

In mathematical expression 1

means the largest integer less than or equal to the value of A.

For example, if there are 14 symbols per slot, the value set to BAT has one of the values from 1 to 13 symbols, the last slot ‘n’ of PDSCH is 4, and the timing offset ‘l’ or ‘k’ is 3, then PUCCH for HARQ feedback can be transmitted at slot index 8.

As another example, if the value set to BAT is 14 symbols, PUCCH for HARQ feedback can be transmitted at slot index 9. Alternatively, 'q' can be directly applied to the number of symbols of BAT.

In the above-described scheme, the base station (or TRP) can expect the UE to transmit PUCCH for HARQ feedback at slot index 'n+l' or 'n+k', but due to BAT, it can expect PUCCH for HAQR feedback to be transmitted from the UE after symbol index of (symbols for BAT-1).

The value of q described in Equation 1 can be applied to a slot or symbol to which the UE can perform PUCCH for HARQ feedback without a separate instruction when the QCL/spatial filter per TRP is changed compared to before based on the integrated TCI state update. Accordingly, the base station can also expect to receive PUCCH for HARQ feedback in the slot or symbol based on the determined value of q.

At this time, the PUCCH resource configuration existing in the slot can be configured through the PUCCH resource indicator configured by DCI and the same method as before.

FIG. 11 is a flowchart illustrating a case where a UE transmits HQRQ feedback according to the first embodiment of the present disclosure.

Figure 11 illustrates the operation of a UE when the UE transmits HARQ feedback according to the first embodiment. According to Figure 11, the operation of a base station corresponding to the operation of the UE can be identified. In other words, the TRPs and/or panels of the base station will be described as base stations below, but this can be interpreted as TRPs connected to the base station or panels connected to the base station.

In addition, when explaining the flow chart of Fig. 11 below, it should be noted that operations that may obscure the gist of the present disclosure are briefly described or omitted.

In step S1100, the UE can receive upper layer signaling from the base station. The upper layer signaling can be, for example, RRC signaling. In addition, the upper layer signaling transmitted from the base station to the UE in step S1100 can include timing offset, BAT information, and TCI type information. Here, the timing offset is time resource information for a response to a PDSCH or PDCCH, and may also be referred to as a slot offset. Since this has been described above as a time offset value, a redundant description will be omitted.

Additionally, BAT information can be set on a symbol basis as described above, and in the current 3GPP standard, it can be set from a minimum of 1 symbol to a maximum of 336 symbols. However, it should be noted that the present disclosure is not limited thereto, and the maximum number of symbols may be further increased.

Additionally, the integrated TCI type information can indicate whether the integrated TCI state is a separate type or a joint type.

In step S1110, the UE can receive integrated TCI indication information. The integrated TCI indication information can be directly indicated by MAC-CE as described above, or can include a case where MAC-CE transmits a list of code points to the UE and additionally dynamically indicates one code point included in the code point list by DCI. In addition, status information for each TRP can be obtained based on the TCI type information of step S1100. Since this is the same as described above, redundant description will be omitted.

At step S1120, the UE can communicate with a base station, for example, TRPs connected to the base station and/or panels connected to the base station.

If the UE receives TCI state change indication information from the base station at step S1130, the UE may proceed to step S1140 to determine a PUCCH slot for HARQ feedback considering BAT. At this time, the PUCCH slot for HARQ feedback may be determined based on whether the DCI includes a slot offset as described above. Since this overlaps with what was described above, further description will be omitted.

In step S1150, the UE can transmit HARQ feedback to the base station in the determined PUCCH slot.

[Example 2: Symbol-level timing setting for HARQ-ACK considering beam application time]

In the first embodiment described above, in configuring PUCCH resources, the method is to consider BAT in units of slots or units of slots and symbols on a time axis that the base station can set to the UE. In contrast, the second embodiment will describe a method for indicating and/or configuring valid resources of PUCCH for HARQ feedback that considers BAT in units of symbols rather than slots.

In general, PUCCH resources for HARQ feedback can be set by using DCI provided by 3GPP at present or by RRC signaling based on timing offset set per slot. In this case, if set by DCI, it can be set by timing indicator included in DCI. In other words, resources within the corresponding slot can be indicated or set by PUCCH resource indicator in DCI.

According to the second embodiment of the present disclosure, a slot-based offset may be used, but may be used when the BAT value is set to a value smaller than 1 slot. In other words, PUCCH may have various time durations from 1 symbol to 14 symbols depending on the format. Therefore, PUCCH resource setting considering the corresponding BAT is possible within a single slot, and the second embodiment of the present disclosure will describe a setting method for this.

According to the method of the second embodiment, if a PUCCH resource for a response to multiple TRPs needs to be set through a single DCI (s-DCI), the PUCCH resource for each TRP needs to consider BAT according to a TCI state change. Therefore, the method can be a method in which the UE transmits HARQ feedback (response) using a PUCCH resource based on the current 3GPP method that does not consider BAT and the PUCCH resource with the lowest or highest index after the BAT based on the last symbol of the PUCCH resource. In other words, when setting a PUCCH for a single HARQ feedback for multiple TRPs with a single PUCCH resource indicator, the BAT can be subgrouped by required TRP and the response can be transmitted through different PUCCH resources. The indexes of different PUCCH resources may be automatically allocated in such a way that the resource having the index indicated by the PUCCH resource indicator and the lowest or highest index among the closest resources among the PUCCH resources of the same format that can be allocated from the symbol immediately after the BAT symbol interval set to be smaller than the slot are allocated.

Let's look at this through a more specific example.

For example, let's assume that there are two TRPs (TRP#1, TRP#2) and BAT is required for PUCCH transmission in case of TRP#2, and the BAT set for TRP#2 is set to 2 symbols. Then, the base station can directly set or indicate the first PUCCH resource for response to TRP#1 using DCI. And the base station can transmit PUCCH for HARQ feedback on the PUCCH resource of the same format that can exist from the 2nd symbol set in the BAT, not the PUCCH resource of TRP#1, implicitly (or automatically). In other words, the second PUCCH resource for response to TRP#2 can be a case where the resource for HARQ feedback is implicitly (or automatically) allocated from the 3rd symbol.

At this time, the index can be specified based on descending or ascending order. Here, the index of the additional PUCCH resource(s) used due to BAT can vary depending on the codebook type of PUCCH. The codebook type of PUCCH can be either a joint type or a separate type.

If the codebook type of PUCCH is a combined type, responses of all TRPs requiring BAT can be transmitted through a resource of a single PUCCH resource index. On the other hand, if the codebook type of PUCCH is a separate type, responses can be transmitted through PUCCH resources having different indices for each TRP. TRPs and indices can be mapped 1:1 in descending or ascending order.

At this time, when considering symbols for BAT, there may not be PUCCH resources available in the same format within a single slot. If there are no PUCCH resources available in the same format within a single slot, the UE can transmit PUCCH in a combined type through the index resource set by the PUCCH resource indicator. In addition, the configuration of the beam used for transmission can apply the state before the indication of the integrated TCI state.

Here is an example to explain this. For example, let's assume that there are four TRPs, TRP#1, TRP#2, TRP#3, and TRP#4, and that BAT is required for all channels for the TRPs except for TRP #1. Then, if the representative TRP sets the response resource for all TRPs to the third index (index #3) through a single DCI (s-DCI), the UE's response to the first TRP (TRP #1) can be transmitted through the indicated or set third index (index #3). And for the remaining TRPs (TRP #2, TRP #3, TRP #4), the responses can be combined and transmitted through the PUCCH resource available in the first symbol after the BAT period.

Whether or not the implicit PUCCH resource configuration described above is supported can be transmitted by the UE together with the UE Capability Information report.

FIG. 12 is a flowchart illustrating a case where a UE transmits HQRQ feedback according to the second embodiment of the present disclosure.

Figure 12 illustrates the operation of a UE when the UE transmits HARQ feedback according to the second embodiment. According to Figure 12, the operation of a base station corresponding to the operation of the UE can be identified. In other words, the TRPs and/or panels of the base station will be described as base stations below, but this can be interpreted as TRPs connected to the base station or panels connected to the base station.

In addition, when explaining the flow chart of Fig. 12 below, it should be noted that operations that may obscure the gist of the present disclosure are briefly described or omitted.

Step S1200 may be the same procedure as step S1100 described above in FIG. 11. However, in FIG. 12, the BAT value may be set to a value smaller than 1 slot as described in the second embodiment.

Step S1210 may be the same procedure as step S1110 described above in FIG. 11, and step S1220 may also be the same procedure as step S1220 described above in FIG. 11. Therefore, since it may be a duplicate description, the same description will be omitted.

In step S1230, the UE may receive TCI state change indication information from the base station (or TRP or panel). At this time, the TCI state change indication information may be set by a single DCI (s-DCI). In addition, the single DCI may have a PUCCH resource indicator set. The PUCCH resource indicator included in the single DCI may be a single PUCCH resource indicator, and a single PUCCH for HARQ feedback for multiple TRPs may be set.

In step S1240, the UE can group TRPs for which BAT is required, and determine different PUCCH resource indices for transmitting HARQ feedback through different PUCCHs for each TRP belonging to each group. The PUCCH resource indices for transmitting HARQ feedback can be determined based on the PUCCH codebook type as described above. Since the description thereof has been described above, a duplicate description will be omitted.

In step S1250, the UE can transmit HARQ feedback to multiple TRPs via PUCCH at the determined resource index.

[Third embodiment: Slot and/or symbol unit timing setting for HARQ-ACK considering beam application time]

The third embodiment described above may be a form that combines the first and second embodiments described above. In other words, it may mean a form that combines the first and second embodiments when configuring PUCCH resources.

As described above, the slot-based configuration method can be such that PUCCH resources can be configured through the first embodiment, and when performing resource selection within a slot, PUCCH resources can be configured through the second embodiment. However, a method for indicating the use of the first and second embodiments may be required. To this end, the configuration of the first embodiment or the configuration of the second embodiment may be indicated through RRC signaling, or the first embodiment or the second embodiment may be configured through DCI.

When indicating that the first embodiment and the second embodiment or the first embodiment and the second embodiment are used simultaneously through RRC signaling, one of the three methods can be indicated using RRC parameters. On the other hand, when using DCI, the technology can be indicated using additional bit(s) in the DCI. When using DCI, when 1 bit is used, only one of the first embodiment or the second embodiment can be selectively used, and when 2 bits are used, one of the first embodiment, the second embodiment, or a combination of the first embodiment and the second embodiment can be selectively indicated.

[Example 4: Selective beam setting considering BAT on UE side]

The fourth embodiment will describe selective beam setting considering BAT on the UE side. When setting resources for DL channels and/or UL channels, the base station can set resources considering the end time of BAT. However, if the base station considers the end time of the BAT section, there may be cases where resource setting is not possible.

For example, if latency is important even though performance is not guaranteed, resource configuration for DL channels and/or UL channels at the base station may be required regardless of whether BAT is terminated. If the resources configured by the base station exist within the BAT termination time, the UE can basically transmit the DL channels and/or UL channels configured after the integrated TCI state indication by applying the previously configured TCI state as it is. Here, 'within the BAT' may mean the BAT time during which the TCI state is determined to need to be changed compared to before after the TCI state indication, and thus a change of the QCL/spatial filter is required.

However, when performing the above operation, the start section of the BAT on the UE side may be restarted and ended based on the last symbol or last slot of the DL channel and/or UL channel. This is because the time when the UE changes the actual QCL/spatial filter can operate after the end point of the channel. In this way, when the UE transmits the corresponding channel using the previous TCI state (e.g., QCL/spatial filter) without any restriction on the DL channel and/or UL channel existing in the BAT, the channels transmitted continuously thereafter may also be affected.

Therefore, the UE defaults to transmitting the corresponding channel using the previous TCI state if there is no separate instruction, but the base station can sanction the UE's operation through a separate instruction. In other words, the base station can transmit information to the UE on whether to perform an operation to skip the configured resources considering BAT at the same time as resource configuration or to transmit the DL channel and/or UL channel as it is by applying the previous state. The base station can transmit to the UE through DCI or MAC-CE when transmitting information indicating whether to skip the configured resources considering BAT or to apply the previous state as it is.

For example, assuming that 1 bit is allocated and transmitted for the purpose of an indicator in DCI or MAC-CE, if the bit is set to '1', the UE can perform beam adjustment as is, ignoring the DL channel and/or UL channel set in the BAT. On the other hand, if the bit is set to '0', the UE can apply the previously set TCI state to the set DL channel and/or UL channel.

As another example, even if it is a BAT interval set in the current 3GPP standard, it is possible to specify specific channels that can be transmitted by applying the previous state. For example, if only PUCCH is specified for a UL channel that unconditionally follows the previous state, if PUSCH is set within the BAT interval, the UE can ignore the set PUSCH resource and operate as if it were a beam application interval.

As another example, the maximum allowable overlapped period can be separately conveyed from the base station to the UE via RRC, DCI or MAC-CE. Here, the period can be a symbol and/or a slot. In addition, the 'allowable overlapped period' can also act as a delimiter for specific functions, for example, skipping or applying the previous state as is, when the overlapping period of the DL channel and/or UL channel configured with the corresponding BAT exists within the configured time period.

The method presented in the embodiments described above can be commonly applied to all channels that may occur when a UE transmits and/or receives a DL channel or an UL channel using a different QCL than the previously configured QCL due to activation or deactivation or indication of an integrated TCI state, not only for PUCCH for HARQ.

Additionally, whether the method described above is supported can be reported to the base station in advance by including it in the report of UE capability information of the UE.

Additionally, all the methods described above can be applied to both single DCI (s-DCI)-based and multi-DCI (m-DCI)-based.

In addition, for all the proposed methods related to PUCCH resources described above, the UE can also transmit information about the associated TRP, which can be information indicating the uniqueness of the TRP, such as a TRP identifier (ID) or a CORESET group identifier (ID). This is because, since the PUCCH resource is set implicitly, information about which TRP the response is for is required in the response.

The operation of the method according to the present disclosure can be implemented as a computer-readable program or code on a computer-readable recording medium. The computer-readable recording medium includes all types of recording devices that store information that can be read by a computer system. In addition, the computer-readable recording medium can be distributed over network-connected computer systems so that the computer-readable program or code can be stored and executed in a distributed manner.

Additionally, the computer-readable recording medium may include hardware devices specifically configured to store and execute program instructions, such as ROM, RAM, flash memory, etc. The program instructions may include not only machine language codes generated by a compiler, but also high-level language codes that can be executed by the computer using an interpreter, etc.

While some aspects of the present disclosure have been described in the context of an apparatus, that may also represent a description of a corresponding method, wherein a block or device corresponds to a method step or a feature of a method step. Similarly, aspects described in the context of a method may also be described as a feature of a corresponding block or item or a corresponding device. Some or all of the method steps may be performed by (or using) a hardware device, such as, for example, a microprocessor, a programmable computer or an electronic circuit. In some embodiments, at least one or more of the most significant method steps may be performed by such a device.

A programmable logic device (e.g., a field-programmable gate array) may be used to perform some or all of the functions of the methods described in this disclosure. A field-programmable gate array may operate in conjunction with a microprocessor to perform one of the methods described in this disclosure. In general, the methods are preferably performed by some hardware device.

Although the present disclosure has been described with reference to preferred embodiments thereof, it will be understood by those skilled in the art that various modifications and changes may be made to the present disclosure without departing from the spirit and scope of the present disclosure as set forth in the claims below.

Claims (20)

1. In a method of user equipment (UE),

   A step of receiving upper layer signaling including first timing offset, beam application time (BAT) and Transmission Configuration Indicator (TCI) type information;

   A step of receiving instruction information for unified TCI for two or more transmission and reception points (TRPs);

   A step of communicating with two or more TRPs based on the first timing offset and the integrated TCI;

   A step of receiving TCI state change indication information from one of the two or more TRPs;

   In response to receiving the TCI state change indication information, determining a first slot for transmitting a hybrid automatic repeat request (HARQ) feedback through a physical uplink control channel (PUCCH) based on the first timing offset and the BAT; and

   Including a step of transmitting the HARQ feedback for each of the two or more TRPs to the two or more TRPs through the first PUCCH in the determined first slot.

   UE's method.
2. In claim 1,

   A step of checking whether the DCI includes a second timing offset when the TCI state change indication information is indicated by downlink control information (DCI);

   a step of determining a second slot to transmit the HARQ feedback based on the second timing offset and the BAT when the second timing offset is included; and

   Further comprising a step of transmitting the HARQ feedback to the two or more TRPs through the second PUCCH in the determined second slot.

   UE's method.
3. In claim 2,

   The second slot to transmit the HARQ feedback is determined by a slot index calculated as the sum of a last slot index of a Physical Downlink Shared Channel (PDSCH) received from the two or more TRPs, a value set by the second timing offset, and an additional slot index value determined by the BAT value.

   UE's method.
4. In claim 3,

   If the number of symbols indicated by the BAT and the number of symbols constituting one slot are not equal, the additional slot index value is the largest integer among the values obtained by dividing the number of symbols indicated by the BAT by the number of symbols constituting one slot plus "1".

   If the number of symbols indicated by the above BAT is a multiple of N of the symbols constituting one slot (where N is a natural number), the additional slot index value is a value obtained by dividing the number of symbols indicated by the BAT by the number of symbols constituting one slot.

   UE's method.
5. In claim 1,

   The first slot is determined by a slot index calculated as the sum of a last slot index of a Physical Downlink Shared Channel (PDSCH) received from the two or more TRPs, a value set by the first timing offset, and an additional slot value determined by the BAT value.

   UE's method
6. In claim 5,

   If the number of symbols indicated by the BAT and the number of symbols constituting one slot are not equal, the additional slot index value is the largest integer among the values obtained by dividing the number of symbols indicated by the BAT by the number of symbols constituting one slot plus "1".

   If the number of symbols indicated by the above BAT is a multiple of N of the symbols constituting one slot (where N is a natural number), the additional slot index value is a value obtained by dividing the number of symbols indicated by the BAT by the number of symbols constituting one slot.

   UE's method.
7. In claim 1,

   A step of grouping TRPs for which the BAT is required among the two or more TRPs, when the BAT is set to a value smaller than one slot and the TCI state change indication information included in a single downlink control information (DCI) is set to transmit the HARQ feedback through one third PUCCH for the two or more TRPs;

   A step of determining different third PUCCH resource indices for transmitting the HARQ feedback for each of the grouped TRPs; and

   Further comprising a step of transmitting the HARQ feedback to the grouped TRPs through a third PUCCH resource indicated by the determined third PUCCH resource index,

   The above HARQ feedback includes a TRP identifier (ID) for each of the grouped TRPs.

   UE's method.
8. In claim 7,

   The above grouped TRPs include a first TRP and a second TRP, and the third PUCCH for the first TRP includes a fourth PUCCH resource directly set by the first TRP, and

   The fifth PUCCH resource for the second TRP is allocated from the symbol after the BAT value when the BAT is required.

   UE's method.
9. In claim 8,

   The above 5th PUCCH resource has the same format as the above 4th PUCCH resource.

   UE's method.
10. In the method of the base station,

    A step of transmitting upper layer signaling including first timing offset, beam application time (BAT) and Transmission Configuration Indicator (TCI) type information to user equipment (UE);

    A step of transmitting, to the UE, indication information for unified TCI for two or more transmission and reception points (TRPs) connected to the base station;

    A step of communicating with the UE through the two or more TRPs based on the first timing offset and the integrated TCI;

    A step of transmitting TCI state change indication information to the UE through one of the two or more TRPs; and

    In response to the TCI state change indication information, the method comprises receiving a hybrid automatic repeat request (HARQ) feedback for each of the two or more TRPs from the UE through a first physical uplink control channel (PUCCH) in a first slot,

    The above first slot is a slot determined based on the first timing offset and the BAT.

    Method of base station.
11. In claim 10,

    A step of transmitting downlink control information (DCI) including the TCI state change indication information and the second timing offset to the UE; and

    Further comprising the step of receiving the HARQ feedback in the second slot based on the second timing offset and the BAT.

    Method of base station.
12. In claim 11,

    The second slot to transmit the HARQ feedback is determined by a slot index calculated as the sum of the last slot index of a physical downlink shared channel (PDSCH) transmitted through the two or more TRPs, a value set by the second timing offset, and an additional slot index value determined by the BAT value.

    Method of base station.
13. In user equipment (UE),

    A transceiver configured to transmit and receive signals with two or more transmission and reception points (TRPs); and

    comprising at least one processor, wherein said at least one processor comprises:

    Receive upper layer signaling including first timing offset, beam application time (BAT) and Transmission Configuration Indicator (TCI) type information;

    Receive instruction information for unified TCI for the above two or more TRPs;

    Communicate with the two or more TRPs based on the first timing offset and the integrated TCI;

    Receive TCI state change indication information from one of the two or more TRPs;

    In response to receiving the TCI state change indication information, determining a first slot for transmitting a hybrid automatic repeat request (HARQ) feedback through a physical uplink control channel (PUCCH) based on the first timing offset and the BAT; and

    Causing the HARQ feedback for each of the two or more TRPs to be transmitted to the two or more TRPs through the first PUCCH in the determined first slot,

    UE.
14. In claim 13,

    At least one processor of the UE:

    When the above TCI state change indication information is indicated by downlink control information (DCI), it is checked whether the DCI includes a second timing offset;

    If the second timing offset is included, determining a second slot for transmitting the HARQ feedback through the PUCCH based on the second timing offset and the BAT; and

    Further causing the HARQ feedback to be transmitted to the two or more TRPs in the second slot determined above,

    UE.
15. In claim 14,

    The second slot to transmit the HARQ feedback is determined by a slot index calculated as the sum of a last slot index of a Physical Downlink Shared Channel (PDSCH) received from the two or more TRPs, a value set by the second timing offset, and an additional slot index value determined by the BAT value.

    UE.
16. In claim 15,

    If the number of symbols indicated by the BAT and the number of symbols constituting one slot are not equal, the additional slot index value is the largest integer among the values obtained by dividing the number of symbols indicated by the BAT by the number of symbols constituting one slot plus "1".

    If the number of symbols indicated by the above BAT is a multiple of N of the symbols constituting one slot (where N is a natural number), the additional slot index value is a value obtained by dividing the number of symbols indicated by the BAT by the number of symbols constituting one slot.

    UE.
17. In claim 13,

    The first slot is determined by a slot index calculated as the sum of a last slot index of a Physical Downlink Shared Channel (PDSCH) received from the two or more TRPs, a value set by the first timing offset, and an additional slot index value determined by the BAT value.

    UE.
18. In claim 17,

    If the number of symbols indicated by the BAT and the number of symbols constituting one slot are not equal, the additional slot index value is the largest integer among the values obtained by dividing the number of symbols indicated by the BAT by the number of symbols constituting one slot plus "1".

    If the number of symbols indicated by the above BAT is a multiple of N of the symbols constituting one slot (where N is a natural number), the additional slot index value is a value obtained by dividing the number of symbols indicated by the BAT by the number of symbols constituting one slot.

    UE.
19. In claim 13,

    At least one processor of the UE:

    When the BAT is set to a value smaller than one slot and the TCI state change indication information included in a single downlink control information (DCI) is set to transmit the HARQ feedback through one third PUCCH for the two or more TRPs, grouping the TRPs for which the BAT is required among the two or more TRPs;

    Determine different third PUCCH resource indices for transmitting the HARQ feedback for each of the grouped TRPs; and

    Further causing the HARQ feedback to be transmitted to the grouped TRPs through the third PUCCH resource indicated by the third PUCCH resource index determined above,

    The above HARQ feedback includes a TRP identifier (ID) for each of the grouped TRPs.

    UE.
20. In claim 19,

    The above grouped TRPs include a first TRP and a second TRP, and the third PUCCH for the first TRP includes a fourth PUCCH resource directly set by the first TRP, and

    For the above 2nd TRP, the 5th PUCCH resource is allocated from the symbol after the BAT value if the BAT is required, and

    The above 5th PUCCH resource has the same format as the above 4th PUCCH resource.

    UE.

Images