Method and apparatus for transmitting and receiving uplink data in a wireless communication system

Abstract

A method performed by a terminal in a wireless communication system according to an embodiment of the present specification includes receiving configuration information related to a plurality of control resource sets (COntrol REsource SETs, CORESETs) from a base station, receiving downlink control information (DCI) from the base station, transmitting a random access preamble to the base station, and receiving a random access response (RAR) from the base station. The random access preamble is transmitted based on an SSB index, and the SSB index is associated with a first CORESET pool index or a second CORESET pool index.

Description

[Technical field]

[0001] The present specification relates to an uplink transmission / reception method and apparatus in a wireless communication system. [Background technology]

[0002] Mobile communication systems were developed to provide voice services while ensuring user activity. However, the scope of mobile communication systems has expanded beyond voice to data services, and currently, the explosive increase in traffic has caused resource shortages and users are demanding faster services, so there is a demand for more advanced mobile communication systems.

[0003] The next generation mobile communication system has many requirements, including the ability to accommodate explosive data traffic, a dramatic increase in transmission rate per user, a significantly increased number of connected devices, extremely low end-to-end latency, and high energy efficiency. To meet these requirements, various technologies are being researched, including Dual Connectivity, Massive Multiple Input Multiple Output (MAMO), In-band Full Duplex, Non-Orthogonal Multiple Access (NOMA), super wideband support, and Device Networking.

[0004] In conventional LTE and NR standards, uplink timing advance configuration / indication supports a single TA value for a Timing Advance Group (TAG) to which a particular cell or group of cells belongs.

[0005] Meanwhile, M-DCI based M-TRP operation (M-TRP operation based on M-DCI) can be performed in an environment where the distance difference between the UE and different TRPs is large. In this case, there may be a propagation delay difference, a slot boundary difference, and an inter-UE panel delay difference between the target TRPs of uplink transmission within the CC / BWP. In particular, this phenomenon may occur more significantly in non-IDEAL backhaul operation where coordination between TRPs is not performed.

[0006] In order to compensate for the timing difference or delay that occurs between TRPs as described above, it is necessary to determine the uplink timing differently for each TRP. For this purpose, it has been agreed that the TCI state of the unified TCI (e.g., joint TCI state, separate TCI state (DL TCI state or UL TCI state)) should be associated with the TAG. Summary of the Invention [Problem to be solved by the invention]

[0007] In order to use the above-mentioned TRP-specific TA (e.g., two TAs corresponding to two TRPs) in M-TRP-based communication, the TA must be acquired by signaling between the terminal and the base station beforehand. On the other hand, if new settings / operations are defined / specified / added to acquire the TRP-specific TA, it is not efficient in terms of the implementation complexity of the terminal / base station.

[0008] The objective of this specification is to propose a method for obtaining a TRP-specific TA taking into account the implementation complexity of the terminal / base station.

[0009] In the existing operation related to TA, when the Time Alignment Timer expires, the terminal selects an arbitrary SSB (SSB index) and then transmits a random access preamble based on the corresponding SSB index. Such an operation is not efficient for acquiring / managing a TRP-specific TA.

[0010] As an example, assume that the Time Alignment Timer for the TA (e.g., the first TA) associated with TRP1 (e.g., the first CORESET pool index) has expired. Since the terminal arbitrarily selects one of multiple SSB indexes, it can select the SSB index associated with TRP2 (or the DL transmission beam of TRP2). In such a case, it may be difficult to obtain the TA for TRP1, or an inaccurate TA may be obtained.

[0011] Another object of the present invention is to propose a method for the administration of TRP specific TA.

[0012] The technical problems to be solved in this specification are not limited to the technical problems mentioned above, and another technical problem not mentioned can be clearly understood by a person having ordinary skill in the art to which the present invention belongs from the description below. [Means for solving the problem]

[0013] A method performed by a terminal in a wireless communication system according to one embodiment of the present specification includes a step of receiving configuration information related to a plurality of control resource sets (Control REsource SETs, CORESETs) from a base station, a step of receiving downlink control information (Downlink Control Information, DCI) from the base station, a step of transmitting a random access preamble to the base station, and a step of receiving a random access response (RAR) from the base station.

[0014] A CORESET based on a first control resource set pool index (CORESET pool index) and a second control resource set pool index (CORESET pool index) is set based on the setting information.

[0015] The DCI includes information about a physical downlink control channel (PDCCH) order, which is used to initiate a random access procedure.

[0016] The information about the PDCCH order includes a Synchronization Signal / Physical Broadcast Channel Block index (SSB index).

[0017] The random access preamble is transmitted based on the SSB index. The random access response (RAR) includes a timing advance command.

[0018] The SSB index is characterized in that it is related to the first CORESET pool index or the second CORESET pool index.

[0019] The method may further include receiving synchronization signal / physical broadcast channel blocks (SS / PBCH blocks, SSBs) from the base station based on a plurality of SSB indexes.

[0020] The multiple SSB indexes may include i) a first SSB index associated with the first CORESET pool index, and ii) a second SSB index associated with the second CORESET pool index.

[0021] The SSB index may be i) one of the first SSB indexes or ii) one of the second SSB indexes.

[0022] The RAR may be received based on monitoring PDCCH candidates in a Search Space set (SS set).

[0023] The SS set may be based on a common search space set (CSS set) or a UE-specific search space set (USS set).

[0024] The SS set may be associated with one or more CORESETs based on the first CORESET pool index or the second CORESET pool index.

[0025] The timing advance command indicates an index related to a timing adjustment, and uses N for calculating a timing advance (TA) based on the index related to the timing adjustment. TA can be instructed.

[0026] The TAG is associated with a first Timing Advance Group (TAG) or a second Timing Advance Group (TAG), the first TAG is associated with the first CORESET pool index, and the second TAG is associated with the second CORESET pool index.

[0027] A Time Alignment Timer associated with the TA may be a first Time Alignment Timer associated with the first TAG or a second Time Alignment Timer associated with the second TAG.

[0028] The first Time Alignment Timer and / or the second Time Alignment Timer are associated with a Primary Timing Advance Group (PTAG), and the configuration for uplink transmission can be released based on the expiration of the first Time Alignment Timer and the second Time Alignment Timer.

[0029] Based on the expiration of a Time Alignment Timer associated with the TA, a random access preamble is transmitted based on an SSB index associated with the expired Time Alignment Timer, and the SSB index associated with the expired Time Alignment Timer may be associated with the first CORESET pool index or the second CORESET pool index.

[0030] The SSB index may be based on one or more SSB indexes, where the one or more SSB indexes include i) a first SSB index associated with the first CORESET pool index and ii) a second SSB index associated with the second CORESET pool index, and a first random access preamble may be transmitted based on the first SSB index and a second random access preamble may be transmitted based on the second SSB index.

[0031] A terminal operating in a wireless communication system according to another embodiment of the present specification includes one or more transceivers, one or more processors, and one or more memories operably connected to the one or more processors and storing instructions that configure the one or more processors to perform operations based on being executed by the one or more processors.

[0032] The operation includes the steps of receiving configuration information related to a plurality of control resource sets (COntrol REsource SETs, CORESETs) from a base station, receiving downlink control information (Downlink Control Information, DCI) from the base station, transmitting a random access preamble to the base station, and receiving a random access response (RAR) from the base station.

[0033] A CORESET based on a first control resource set pool index (CORESET pool index) and a second control resource set pool index (CORESET pool index) is set based on the setting information.

[0034] The DCI includes information about a physical downlink control channel (PDCCH) order, which is used to initiate a random access procedure.

[0035] The information about the PDCCH order includes a Synchronization Signal / Physical Broadcast Channel Block index (SSB index).

[0036] The random access preamble is transmitted based on the SSB index. The random access response (RAR) includes a timing advance command.

[0037] The SSB index is characterized in that it is related to the first CORESET pool index or the second CORESET pool index.

[0038] An apparatus according to another embodiment herein includes one or more memories and one or more processors operatively coupled to the one or more memories.

[0039] The one or more memories contain instructions that, upon being executed by the one or more processors, configure the one or more processors to perform operations.

[0040] The operation includes the steps of receiving configuration information related to a plurality of control resource sets (COntrol REsource SETs, CORESETs) from a base station, receiving downlink control information (Downlink Control Information, DCI) from the base station, transmitting a random access preamble to the base station, and receiving a random access response (RAR) from the base station.

[0041] A CORESET based on a first control resource set pool index (CORESET pool index) and a second control resource set pool index (CORESET pool index) is set based on the setting information.

[0042] The DCI includes information about a physical downlink control channel (PDCCH) order, which is used to initiate a random access procedure.

[0043] The information about the PDCCH order includes a Synchronization Signal / Physical Broadcast Channel Block index (SSB index).

[0044] The random access preamble is transmitted based on the SSB index. The random access response (RAR) includes a timing advance command.

[0045] The SSB index is characterized in that it is related to the first CORESET pool index or the second CORESET pool index.

[0046] According to yet another embodiment of the present disclosure, one or more non-transitory computer-readable media may store one or more instructions.

[0047] One or more instructions executable by one or more processors configure the one or more processors to perform operations.

[0048] The operation includes the steps of receiving configuration information related to a plurality of control resource sets (COntrol REsource SETs, CORESETs) from a base station, receiving downlink control information (Downlink Control Information, DCI) from the base station, transmitting a random access preamble to the base station, and receiving a random access response (RAR) from the base station.

[0049] A CORESET based on a first control resource set pool index (CORESET pool index) and a second control resource set pool index (CORESET pool index) is set based on the setting information.

[0050] The DCI includes information about a physical downlink control channel (PDCCH) order, which is used to initiate a random access procedure.

[0051] The information about the PDCCH order includes a Synchronization Signal / Physical Broadcast Channel Block index (SSB index).

[0052] The random access preamble is transmitted based on the SSB index. The random access response (RAR) includes a timing advance command.

[0053] The SSB index is characterized in that it is related to the first CORESET pool index or the second CORESET pool index.

[0054] According to another embodiment of the present specification, a method performed by a base station in a wireless communication system includes a step of transmitting configuration information related to a plurality of control resource sets (COntrol REsource SETs, CORESETs) to a terminal, a step of transmitting downlink control information (Downlink Control Information, DCI) to the terminal, a step of receiving a random access preamble from the terminal, and a step of transmitting a random access response (RAR) to the terminal.

[0055] Based on the configuration information, a CORESET based on a first control resource set pool index (CORESET pool index) and a second control resource set pool index (CORESET pool index) is configured.

[0056] The DCI includes information about a physical downlink control channel (PDCCH) order, which is used to initiate a random access procedure.

[0057] The information about the PDCCH order includes a Synchronization Signal / Physical Broadcast Channel Block index (SSB index).

[0058] The random access preamble is received based on the SSB index. The random access response (RAR) includes a timing advance command.

[0059] The SSB index is characterized in that it is related to the first CORESET pool index or the second CORESET pool index.

[0060] A base station operating in a wireless communication system according to still another embodiment of the present specification includes one or more transceivers, one or more processors, and one or more memories operably connected to the one or more processors and storing instructions that configure the one or more processors to perform operations based on being executed by the one or more processors.

[0061] The operations include transmitting configuration information related to a plurality of control resource sets (COntrol REsource SETs, CORESETs) to a terminal, transmitting downlink control information (DCI) to the terminal, receiving a random access preamble from the terminal, and transmitting a random access response (RAR) to the terminal.

[0062] A CORESET based on a first control resource set pool index (CORESET pool index) and a second control resource set pool index (CORESET pool index) is set based on the setting information.

[0063] The DCI includes information about a physical downlink control channel (PDCCH) order, which is used to initiate a random access procedure.

[0064] The information about the PDCCH order includes a Synchronization Signal / Physical Broadcast Channel Block index (SSB index).

[0065] The random access preamble is received based on the SSB index. The random access response (RAR) includes a timing advance command.

[0066] The SSB index is characterized in that it is related to the first CORESET pool index or the second CORESET pool index. Effect of the Invention

[0067] According to an embodiment of the present specification, a random access preamble is transmitted based on an SSB index indicated by a DCI associated with a PDCCH order. The SSB index is associated with a TRP (i.e., a CORESET pool index). This can lead to the following effects:

[0068] 1) A TRP-specific TA can be obtained through an existing RACH procedure initiated by a PDCCH order. Therefore, the implementation complexity of the terminal / base station can be reduced compared to setting / defining new parameters or separate signaling to obtain a TRP-specific TA.

[0069] 2) A TRP-specific TA can be obtained and used for UL transmission before uplink channel / signal transmission except for PRACH transmission (i.e., random access preamble transmission). As an example, transmission of Msg3 (PUSCH) based on a random access procedure initiated by a PDCCH order can be performed based on a TRP-specific TA indicated via the RAR.

[0070] 3) By utilizing the obtained TRP-specific TA, the reliability of M-DCI-based TRP-specific UL scheduling / UL transmission is improved (improvement of uplink timing accuracy per TRP).

[0071] According to an embodiment of the present specification, when a Time Alignment Timer associated with a TA expires, a random access preamble is transmitted based on an SSB index associated with the expired Time Alignment Timer, where the SSB index is associated with a first CORESET pool index or a second CORESET pool index.

[0072] Therefore, the procedure performed after the expiration of the Time Alignment Timer of a TRP-specific TA can be performed more efficiently in terms of acquisition / management of the TRP-specific TA, i.e., after the expiration of the Time Alignment Timer of a TRP-specific TA (e.g., TA1 for TRP1), the acquisition of an incorrect TA is prevented due to the SSB index (e.g., SSB index associated with TRP2) selected by the terminal.

[0073] The effects obtained in this specification are not limited to those mentioned above, and other effects not mentioned will be clearly understood by those having ordinary skill in the art to which the present invention pertains from the description below. [Brief description of the drawings]

[0074] [Figure 1] 1 illustrates an example MAC RAR according to an embodiment of the present specification. [Diagram 2] 1 illustrates a Timing Advance Command MAC CE according to an embodiment of the present specification. [Diagram 3] 1 is a flowchart illustrating a method performed by a terminal in a wireless communication system according to an embodiment of the present specification. [Figure 4]11 is a flowchart illustrating a method performed by a base station in a wireless communication system according to another embodiment of the present disclosure. [Diagram 5] FIG. 2 illustrates a configuration of a first device and a second device according to an embodiment of the present specification. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0075] Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. The detailed description disclosed below in conjunction with the accompanying drawings is intended to describe exemplary embodiments of the present invention, and is not intended to show the only embodiments in which the present invention can be practiced. The following detailed description includes specific details to provide a complete understanding of the present invention. However, those skilled in the art will appreciate that the present invention can be practiced without such specific details.

[0076] In some cases, well-known structures and devices may be omitted or shown in block diagram form focusing on the core functions of each structure and device in order to avoid obscuring the concept of the present invention.

[0077] Hereinafter, downlink (DL) means communication from a base station to a terminal, and uplink (UL) means communication from a terminal to a base station. In the downlink, a transmitter may be part of the base station, and a receiver may be part of the terminal. In the uplink, a transmitter may be part of the terminal, and a receiver may be part of the base station. The base station may be expressed as a first communication device, and the terminal may be expressed as a second communication device. A base station (BS) may be replaced with terms such as a fixed station, NodeB, evolved-NodeB (eNB), Next Generation NodeB (gNB), base transceiver system (BTS), access point (AP), network (5G network), AI system, road side unit (RSU), vehicle, robot, drone (Unmanned Aerial vehicle, UAV), Augmented Reality (AR) device, Virtual Reality (VR) device, etc. In addition, a terminal may be fixed or mobile, and may be replaced with terms such as User Equipment (UE), Mobile Station (MS), user terminal (UT), Mobile Subscriber Station (MSS), Subscriber Station (SS), AdvanceD Mobile Station (AMS), Wireless terminal (WT), Machine-Type Communication (MTC) device, Machine-to-Machine (M2M) device, Device-to-Device (D2D) device, vehicle, robot, AI module, Unmanned Aerial Vehicle (UAV), Augmented Reality (AR) device, Virtual Reality (VR) device, etc.

[0078] Multi-TRP (Transmission / Reception Point) related operations

[0079] The M-TRP transmission method, in which M TRPs transmit data to one terminal (User equipment, UE), can be broadly divided into two types: eMBB M-TRP transmission, which is a method for increasing the transmission rate, and ULLCM-TRP transmission, which is a method for increasing the reception success rate and reducing latency.

[0080] MTRP URLLC

[0081] In the method proposed in this specification, DL MTRP-URLLC means that multiple TRPs transmit the same data / DCI using different layer / time / frequency resources. For example, TRP1 transmits the same data / DCI using resource 1, and TRP2 transmits the same data / DCI using resource 2. A UE configured with the DL MTRP-URLLC transmission method receives the same data / DCI using different layer / time / frequency resources. At this time, the UE is instructed by the base station which QCL RS / type (i.e., DL TCI state) to use in the layer / time / frequency resource that receives the same data / DCI. For example, when the same data / DCI is received in resource 1 and resource 2, the DL TCI state to be used in resource 1 and the DL TCI state to be used in resource 2 are instructed. Since the UE receives the same data / DCI through resource 1 and resource 2, high reliability can be achieved. Such DL MTRP URLLC can be applied to the PDSCH / PDCCH.

[0082] Conversely, UL MTRP-URLLC means that multiple TRPs receive the same data / UCI from one UE using different layer / time / frequency resources. For example, TRP1 receives the same data / UCI from the UE using resource 1, and TRP2 receives the same data / UCI from the UE using resource 2, and then shares the received data / UCI through a connected backhaul link between the TRPs. A UE configured with a UL MTRP-URLLC transmission method transmits the same data / UCI using different layer / time / frequency resources. At this time, the UE is instructed by the base station as to which Tx beam and which Tx power (i.e., UL TCI state) to use in the layer / time / frequency resource that transmits the same data / UCI. For example, when the same data / UCI is transmitted in resource 1 and resource 2, the UE is instructed on the UL TCI state to be used in resource 1 and the UL TCI state to be used in resource 2. Such UL MTRP URLLC can be applied to PUSCH / PUCCH.

[0083] SDCI or MDCI based MTRP transmission

[0084] In addition, from the viewpoint of DCI (downlink control information) transmission, the M-TRP (multiple TRP) transmission method can be divided into i) M-DCI (multiple DCI) based M-TRP transmission, in which each TRP transmits different DCI, and ii) S-DCI (single DCI) based M-TRP transmission, in which one TRP transmits DCI. For example, in the case of S-DCI, all scheduling information for data transmitted by the M TRP must be transmitted through one DCI, so it can be used in an ideal BH (ideal BackHaul) environment where dynamic cooperation between two TRPs is possible.

[0085] R16 NR MTRP transmission

[0086] The R16 NR standard supports S-DCI based MTRP PDSCH and M-DCI based MTRP PDSCH transmission methods.

[0087] R16 M-DCI based MTRP PDSCH

[0088] M-DCI based MTRP PDSCH transmission is a method in which each TRP schedules and transmits PDSCH via DCI. That is, TRP1 transmits PDSCH1 via DCI1, and TRP2 transmits PDSCH2 via DCI2. When PDSCH1 and PDSCH2 overlap in the same frequency time resource, two PDSCHs are received for the same RE, so resource efficiency is improved and transmission capacity is increased. For this reason, the R16 standard introduces a CORESET pool, which is a group of multiple CORESETs, and TRP1 transmits PDCCH via a CORESET belonging to CORESET pool 0, and the PDSCH scheduled by the PDCCH is also transmitted by TRP1. TRP2 transmits PDCCH via a CORESET belonging to CORESET pool 1, and the PDSCH scheduled by the PDCCH is also transmitted by TRP2. A specific TRP can also schedule PUSCH transmission to a UE via a CORESET belonging to each CORESET pool. For PUCCH, some PUCCH resources are scheduled by TRP1 to receive UCI, and the remaining PUCCH resources are scheduled by TRP2 to receive UCI. In the case of PUSCH and PUCCH, the channels scheduled / used by each TRP are TDM-multiplexed to prevent overlap, so an increase in transmission capacity cannot be expected, but the UE can transmit independent PUSCH / PUCCH to TRP1 and 2.

[0089] In addition, the UE can recognize a PUSCH (or PUCCH) scheduled by DCI received in a different CORESET (or a CORESET belonging to a different CORESET group) as a PUSCH (or PUCCH) transmitted via a different TRP, or as a PUSCH (or PUCCH) of a different TRP. In addition, the scheme for UL transmission (e.g., PUSCH / PUCCH) transmitted in a different TRP can be similarly applied to UL transmission (e.g., PUSCH / PUCCH) transmitted in a different panel belonging to the same TRP.

[0090] The CORESET group ID (or a CORESET pool index having the same meaning) described / mentioned in this specification may mean an index / identification information (e.g., ID) for distinguishing a CORESET for each TRP / panel. And, a CORESET group is a group / union of CORESETs distinguished by an index / identification information (e.g., ID) for distinguishing a CORESET for each TRP / panel / the CORESET group ID, etc. As an example, the CORESET group ID may be specific index information defined in a CORESET configuration. As an example, a CORESET group may be set / indicated / defined by an index defined in a CORESET configuration for each CORESET. And / or, the CORESET group ID means an index / identification information / indicator for distinguishing / identifying CORESETs set / associated with each TRP / panel, and the CORESET group ID described / mentioned in this specification may be expressed as a specific index / specific identification information, specific indicator for distinguishing / identifying CORESETs set / associated with each TRP / panel. The CORESET group ID, i.e., a specific index / specific identification information / specific indicator for distinguishing / identifying between CORESETs configured / associated with each TRP / panel, can be configured / indicated via higher layer signaling (e.g., RRC signaling) / L2 signaling (e.g., MAC-CE) / L1 signaling (e.g., DCi), etc.For example, PDCCH detection for each TRP / panel may be configured / instructed to be performed on a per-CORESET group basis, and / or uplink control information (e.g., CSI, HARQ-A / N, SR) and / or uplink physical channel resources (e.g., PUCCH / PRACH / SRS resources) may be configured / instructed to be separately managed / controlled for each TRP / panel on a per-CORESET group basis, and / or HARQ A / N (process / retransmission) for PDSCH / PUSCH, etc. scheduled for each TRP / panel may be managed on a per-CORESET group basis.

[0091] For example, a ControlResourceSet information element (IE), which is an upper layer parameter, is used to configure a time / frequency control resource set (CORESET). As an example, the control resource set (CORESET) is related to detection and reception of downlink control information. The ControlResourceSet IE may include a CORESET related ID (e.g., controlResourceSetID), a CORESET pool index for the CORESET (e.g., CORESETPoolIndex), a time / frequency resource configuration of the CORESET, TCI information related to the CORESET, etc. As an example, a CORESET pool index (e.g., CORESETPoolIndex) can be set to 0 or 1. In the above description, a CORESET group corresponds to a CORESET pool, and a CORESET group ID corresponds to a CORESET pool index (e.g., CORESETPoolIndex). A ControlResourceSet (e.g., CORESET) can be configured via upper layer signaling (e.g., RRC).

[0092] R17 NR MTRP transmission

[0093] The R17 NR standard supports MTRP PDCCH repeat transmission, MTRP PDCCH / PDSCH SFN transmission, S-DCI based MTRP PUSCH repeat transmission, and single PUCCH resource based MTRP PUCCH repeat transmission. All of these transmission techniques are URLLC target enhancement for increased reliability, in which the same contents (i.e., DCI, UL TB, or UCI) are repeatedly transmitted. In the case of MTRP PDCCH repeat transmission, it is repeatedly transmitted after TDM or FDM, MTRP PDCCH / PDSCH SFN is repeatedly transmitted at the same time / frequency / layer, S-DCI based MTRP PUSCH repeat transmission is TDM, and single PUCCH resource based MTRP PUCCH repeat transmission is repeatedly transmitted after TDM.

[0094] R17 MTRP SFN PDCCH

[0095] As a special case of MTRP PDCCH repeated transmission, multiple TRPs may repeatedly transmit the same DCI via the same time / frequency / DMRS port, which can be called SFN PDCCH transmission. However, for SFN PDCCH transmission, the base station sets multiple TCI states in one CORESET instead of setting multiple CORESETs with different TCI states. When the UE receives a PDCCH candidate through an SS set connected to that one CORESET, it performs channel estimation and attempts to decode the PDCCH DMRS using all the corresponding multiple TCI states.

[0096] R17 MTRP SFN PDSCH

[0097] When the MTRP PDSCH is repeatedly transmitted, the two TRPs repeatedly transmit the channel on different resources. However, as a special case, when the resources used by the two TRPs are the same, that is, when the same channel is repeatedly transmitted through the same frequency, time, and layer (=DMRS port), the reliability of the channel can be improved. In this case, the repeatedly transmitted same channel is received together on the air because the resources are not separated, so it is recognized as one channel from the perspective of the receiving end. In the R17 NR standard, two DL TCI states for PDSCH DMRS reception can be set for PDSCH SFN transmission.

[0098] R17 single PUCCH resource based MTRP PUCCH repeated transmission

[0099] In the R17 NR standard, the base station activates / configures two spatial relation info pieces to a single PUCCH resource for single PUCCH resource based MTRP PUCCH transmission (activates / configures two PC (power control) parameter sets in the case of FR1), and when UL UCI is transmitted through the PUCCH resource, the UE uses the spatial relation info pieces to indicate the spatial relation info pieces for TRP1 and TRP2, respectively. For example, the UE is instructed on the Tx beam / PC parameters for TRP1 through the value indicated in the first spatial relation info, and performs PUCCH transmission in the TO corresponding to TRP1 using this information. Similarly, the UE is instructed on the Tx beam / PC parameters for TRP2 through the value indicated in the second spatial relation info, and performs PUCCH transmission in the TO corresponding to TRP2 using this information.

[0100] In the Rel 17 standardization meeting, the configuration method is enhanced so that two spatial relation info are configured in the PUCCH resource for MTRP PUCCH repeated transmission. That is, when PC (power control) parameters such as PLRS, Alpha, P0, and Closed loop index are configured in each spatial relation info, the spatial relation RS can be configured. As a result, the PC information and spatial relation RS information corresponding to two TRPs can be configured through two spatial relation info, and the UE transmits PUCCH using the first spatial relation info in TO1, and transmits the same UCI (i.e., CSI, ACKNAK, SR) PUCCH using the second spatial relation info in TO2. Hereinafter, the PUCCH resource configured with two spatial relation info is named MTRP PUCCH resource, and the PUCCH resource configured with one spatial relation info is named STRP PUCCH resource.

[0101] Meaning of TCI state / beam indication

[0102] In the method proposed herein, the use ( / mapping) of a specific TCI state (or TCI) when receiving data / DCI / UCI for a certain frequency / time / space resource means, in the case of DL, estimating a channel from a DMRS using a QCL type and QCL RS indicated by the corresponding DL TCI state in the frequency / time / space resource, and receiving / demodulating data / DCI using the estimated channel. In the case of UL, it means transmitting / modulating a DMRS and data / UCI using a Tx beam and / or Tx power indicated by the corresponding ULTCI state in the frequency / time / space resource.

[0103] The UL TCI state includes Tx beam or Tx power information of the UE, and instead of the TCI state, spatial relation info, etc., can be set to the UE via other parameters. The ULTCI state may be directly indicated in the UL grant DCI, or may mean spatial relation info of the SRS resource indicated via the SRI field of the UL grant DCI. Or, it may mean an OL Tx power control parameter (j: index for open loop parameters Po & alpha (maximum 32 parameter value sets per cell), q_d: index of DL RS resource for PL measurement (maximum 4 measurements per cell), l: closed loop power control process index (maximum 2 processes per cell)) linked to a value indicated via the SRI field of the UL grant DCI. Or, in R17 NR, the UL TCI can be indicated using the DL grant DCI.

[0104] For convenience of explanation, this specification applies the proposed method assuming cooperative transmission / reception between two TRPs, but it can be extended to a multi-TRP environment with three or more TRPs and a multi-panel environment. Different TRPs may be recognized as different TCI states in the UE, and the UE receiving / transmitting data / DCI / UCI using TCI state1 means receiving / transmitting data / DCI / UCI from / to TRP1.

[0105] In this specification, TO (Transmission Occasion) means each channel transmitted at a different time when multiple channels are TDMed, each channel transmitted to a different frequency / RB when FDMed, and each channel transmitted to a different layer / beam / DMRS port when SDMed. One TCI state is mapped to each TO. When the same channel is repeatedly transmitted, complete DCI / data / UCI is transmitted to one TO, and the receiving end receives multiple TOs to increase the reception success rate.

[0106] TA(Timing advance) related procedure

[0107] The transmission of uplink frame number i from the terminal (User Equipment, UE) starts from the start of the corresponding downlink frame at the terminal. It must start before JPEG2025514184000002.jpg510.

[0108] The uplink timing (i.e. uplink frame) associated with JPEG2025514184000003.jpg513 is based on Table 1 below.

[0109] [Table 1]

[0110] Table 1 JPEG2025514184000005.jpg510 is N TA and N TA,offset It can be calculated / determined based on N TA and N TA,offset is set / applied as follows:

[0111] N TA 1) Set via RAR (Random access response), 2) Set via Timing advance command (MAC-CE)

[0112] N TA,offset 1) Set a specific value for each serving cell, 2) Apply a predefined value to the serving cell according to Duplex mode / FR

[0113] In the following, TA,offset and N TA This section explains in detail how to set up and apply the above.

[0114] N TA,offset

[0115] Case 1) How to set a specific value for each serving cell

[0116] For example, the terminal is TA,offset The UE may receive configuration information (e.g., ServingCellConfigCommon Information) including information regarding the UE. The configuration information may be received based on RRC signaling. Table 2 below shows an example of the configuration information.

[0117] [Table 2]

[0118] Case 2) How to apply predefined values ​​to the serving cell according to Duplex mode / FR

[0119] For example, the terminal uses a predefined N TA,offset The value of N can be adapted to the serving cell. TA,offset The values ​​of are shown below.

[0120] [Table 3]

[0121] N TA

[0122] Case 1) Setting via RAR (Random access response)

[0123] For example, in a random access procedure (e.g., a 2-step RACH procedure or a 4-step RACH procedure), the terminal receives an RAR from the base station. TA can be determined / set. Specifically, the RAR may include a timing advance command. The timing advance command indicates an index value (e.g., index value TA) related to a timing adjustment. Based on the index value, N TA can be determined (see Table 5 below). The RAR may be based on the MAC RAR. Hereinafter, with reference to FIG.

[0124] FIG. 1 illustrates a MAC RAR according to an embodiment of the present specification.

[0125] As shown in Fig. 1, the MAC RAR may include R (Reserved bit), a Timing Advance Command, a UL Grant, and a Temporary C-RNTI. Table 4 below illustrates an example of the MAC payload of the MAC RAR.

[0126] [Table 4]

[0127] Table 5 below illustrates examples of transmission timing adjustments based on the Timing advance command.

[0128] [Table 5]

[0129] Case 2) Setting via Timing advance command (MAC-CE)

[0130] For example, N TA can be set / determined based on the MAC-CE. TA is determined based on a Timing Advance Command MAC CE. The Timing Advance Command MAC CE may include a timing advance command. N based on the timing advance command TA The determination of is the same as that in Case 1, so a duplicated description will be omitted (see Table 5). The Timing Advance Command MAC CE will be described below with reference to FIG.

[0131] FIG. 2 illustrates a Timing Advance Command MAC CE according to an embodiment of the present specification.

[0132] As shown in Figure 2, the Timing Advance Command MAC CE may include a TAG ID and a Timing Advance Command. Table 6 below illustrates an example of the payload of the Timing Advance Command MAC CE.

[0133] [Table 6]

[0134] TAG(Timing advance group)

[0135] Timing Advance Group (TAG) refers to a group of serving cells that use the same Timing Advance value. Table 7 below illustrates the definition of TAG and configuration information related to TAG.

[0136] [Table 7-1]

[0137] [Table 7-2]

[0138] [Table 7-3]

[0139] Procedure

[0140] Uplink time alignment can be performed based on Table 8 below.

[0141] [Table 8-1]

[0142] [Table 8-2]

[0143] [Table 8-3]

[0144] The above contents (Multi-TRP, Timing Advance, etc.) may be applied in combination with the methods proposed in this specification, which will be described later, or serve to clarify the technical features of the methods proposed in this specification. The methods described below are merely divided for the convenience of explanation, and it goes without saying that some components of one method can be replaced with some components of another method, or can be combined with each other and applied.

[0145] In the following, we will describe i) how a base station configures / instructs multiple TAs for a specific CC / BWP in an uplink transmission of a terminal, and ii) how a terminal requests / acquires multiple TAs, and then propose the subsequent terminal operation.

[0146] According to the 3GPP standard up to NR Rel-17, the timing advance (TA) setting for the UE uplink transmission of the BS to compensate for the propagation delay between the BS and the UE can be performed via higher layer signaling. In addition, the TA for a specific cell(s) can be separately set / managed according to the concept / definition of a timing advance group (TAG).

[0147] Currently, there is no method to support multiple TA values ​​in a specific cell. However, enhancements will be made to allow multiple (2) TA values ​​to be set / indicated in a specific CC / BWP in consideration of scenarios where there is a large difference in distance between different target TRPs and the UE when transmitting M-TRP UL.

[0148] In this case, it is necessary to discuss how the base station sets / instructs multiple TA values ​​to the terminal, and / or how the connection relationship between the multiple TA values ​​and the terminal UL channel / RS is performed. As described in the Rel-18 MIMO WID objective (RP-213598) in Table 9 below, the setting of TA values ​​for multi-DCI (M-DCI) based M-TRP operation is considered.

[0149] [Table 9]

[0150] Here, the TA (TA value) can be based on the description of FIG. 2 and the above-mentioned TA (Timing advance) related procedure.

[0151] In the RAN1 and RAN2 standards before Rel-18, the base station is required to set the N TA and N TA,offset The base station manages the number of nodes via the value N TA i) N via RAR MAC CE TA or ii) set N via TA command MAC CE (Timing Advance Command MAC CE). TAIn addition, the base station uses the concept of TAG (Timing Advance Group) to set up to four TAGs for a specific cell or cell combination to the terminal. The base station sets N TA In other words, it updates / manages the N TA The value can be determined / set based on the RAR MAC CE / TA command MAC CE for each TAG.

[0152] In Rel-18 MIMO, in order to support different TA values ​​of terminals according to the target TRP, i) the base station TA (or / and N TA,offset ) value, or ii) the base station sets two values ​​for TRP-specific in a specific CC / BWP, TA or / and N TA,offset In addition to the value, a separate parameter (e.g. N TA,TRP1 and / or N TA,TRP2 ) can be set in a specific CC / BWP via MAC CE signalling. In the case of method ii, the TA offset according to the separate parameter may need to be additionally subtracted / added in the existing TA value calculation of the terminal. In the following, the two TA values ​​managed by methods i and / or ii can be expressed as TA1 (or first TA) and TA2 (or second TA). Here, the two TA values ​​can correspond to two TAGs. For example, TA1 corresponding to TRP1 is associated with TAG1, and TA2 corresponding to TRP2 is associated with TAG2.

[0153] As described in WID, a scenario for supporting two TA values ​​is M-DCI based M-TRP operation. In M-DCI based M-TRP operation, each TRP can be classified based on a CORESET pool index associated with CORESET(s) present in BWP. Based on the CORESET pool index, each TRP is classified into i) a TRP performing DL transmission (e.g., PDCCH, PDSCH) or / and ii) a target TRP for UL transmission. For example, CORESETs 0 and 1 with CORESET pool index 0 correspond to TRP 1, and CORESETs 2 and 3 with CORESET pool index 1 correspond to TRP 2.

[0154] On the other hand, in the unified TCI framework introduced in Rel-17 MIMO, a base station can dynamically indicate a specific reference RS to be used as a common beam for the DL / UL receiving / transmitting beams of a terminal by utilizing DL / UL joint TCI state and / or DL / UL separate TCI state.

[0155] The DL / UL joint TCI state can be based on the joint TCI state configured for UL and DL operation. When the unified TCI-State Type of the serving cell is set to "joint", the joint TCI state can be set based on dl-OrJointTCI-StateList.

[0156] The DL / UL separate TCI state can be based on the DL TCI state and / or the ULTCI state. When the unified TCI-StateType of the serving cell is set to "separate", the DL TCI state can be set based on the dl-OrJointTCI-StateList and the UL TCI state can be set based on the ul-TCI-ToAddModList.

[0157] The TCI state (e.g., joint / DL TCI state) can be indicated / set based on dl-OrJoint-TCIStateList in PDSCH-config. dl-OrJoint-TCIStateList can i) provide a list of up to 128 TCI states (explicitlist→dl-OrJointTCI-StateToAddModList), or ii) indicate the serving cell and (DL / UL) BWP for which the TCI state list (dl-OrJointTCI-StateToAddModList) is defined (unifiedTCI-StateRef→ServingCellAnd-id). The TCI state (e.g., joint / DL TCI state) can provide a reference RS for quasi co-location of DM-RS of PDSCH, DM-RS of PDCCH, and CSI-RS. The TCI state (e.g., joint TCI state) can provide a reference RS for determining a dynamic grant based PUSCH, a configured grant based PUSCH, a PUCCH resource, and an uplink transmit spatial filter (UL Tx spatial filter) for an SRS.

[0158] The UL TCI state can be indicated / set by ul-TCI-StateList in BWPUplinkDedicated, which i) provides a list of up to 64 UL TCI states (explicitlist→ul-TCI-ToAddModList) or ii) can indicate the serving cell and UL BWP for which the UL TCI state applicable to the UL BWP is defined (unified TCI-StateRef→ServingCellAndBWP-Id).

[0159] The receive / transmit beam of a DL / UL channel / RS that is not a common beam target can be set as follows: Based on RRC and MAC CE signaling, the TCI state of the unified TCI framework can be set for each channel / RS.

[0160] Up until Rel-17, standardization was only carried out for M / N, the number of DL / UL common beams (number of DL / UL TCI states) supported in the unified TCI framework, when M / N = 1. In other words, the unified TCI framework was not previously supported for M-TRP. Specifically, in the case of a serving cell with two CORESET pool indices set (more than one value for the CORESETPoolIndex), the unified TCI-StateType is not set.

[0161] Here, M / N means the number of DL common beams (M) and / or the number of UL common beams (N). For example, M / N=1 means that the number of DL common beams (DL TCI state) and / or the number of UL common beams (UL TCI state) is 1. For example, M / N=1 means that the number of DL and UL common beams (joint TCI state) is 1.

[0162] When M / N>1 is supported in Rel-18, two or more TCI states and source / target TRPs have a connection relationship.

[0163] In particular, in M-DCI based M-TRP operation, two or more TCI states corresponding to M / N>1 may have a concatenated relationship with the CORESET pool index. As described above, two TA values ​​for multiple TRPs can be set / indicated by higher layer signaling such as MAC CE as in the conventional standard.

[0164] For terminals supporting unified TCI applied to FR 2 (terminals after Rel-17), multiple TA values ​​can be concatenated / corresponded to two or more TCI states corresponding to M / N>1. For example, when M / N=2 or / and N=2, the first (first / lowest) set / indicated TCI state corresponds to TA1 (e.g. TAG1 or TA1 for TAG1), and the second (second / second-lowest) set / indicated TCI state corresponds to TA2 (e.g. TAG2 or TA2 for TAG2).

[0165] Specifically, a specific payload may be included / added / defined in the MAC CE to set / assign / activate a TA value for each of two or more TCI states corresponding to M / N>1. For example, the MAC CE message for setting the two TA values ​​may have a payload for the target TCI state(s) (group) for assigning each TA value (e.g., TA1 and TA2).

[0166] The agreements for multiple TA values ​​are as shown in Table 10 below.

[0167] [Table 10-1]

[0168] [Table 10-2]

[0169] [Table 10-3]

[0170] The operations / methods / terms according to the embodiments of the present specification described later are based on Table 10. For example, the operations / methods / terms according to the embodiments of the present specification described later can be interpreted / modified / applied based on Table 10.

[0171] For example, multiple TA values ​​may represent multiple TAGs (Timing Advance Groups) or multiple TAG IDs. One TA value may represent one TAG (TAG ID).

[0172] For example, multiple TA values ​​means TA values ​​corresponding to multiple TAGs (multiple TAG IDs). One TA value is a TA value for one TAG (TAG ID) (see Table 1). JPEG2025514184000021.jpg58).

[0173] In a TCI state configuration (TCI state pool) for a unified TCI, the two TRP-specific TA values ​​(e.g., two TAGs or TAs corresponding to two TAGs) may be concatenated / corresponded to a specific TCI state(s) (group). When two TA values ​​are concatenated / corresponded to two TCI states corresponding to the corresponding M / N>1, the UE performs UL transmission using the TRP-specific TA value concatenated to each TCI state in UL transmission using each TCI state. For example, the timing of UL transmission based on a first TCI state may be determined based on a TA associated with the first TCI state (e.g., a first TAG or a first TA for the first TAG), and the timing of UL transmission based on a second TCI state may be determined based on a TA associated with the second TCI state (e.g., a second TAG or a second TA for the second TAG).

[0174] However, even if the unified TCI is supported by the terminal, the UL spatialRelationInfo or / and reference RS of the UL TCI cannot be applied in FR1 (Frequency Range 1). For example, the UE capability for spatialRelation of the terminal can be defined as shown in Table 11 below.

[0175] [Table 11]

[0176] With reference to Table 11, spatial relation for PUCCH and SRS is not supported for FR1 (eg, terminal operation in FR1).

[0177] Therefore, for FR1, if the base station sets / instructs the two TA values ​​using the unified TCI framework, there may be ambiguity in the terminal operation.

[0178] As mentioned above, this specification describes i) a method in which a base station sets / instructs multiple TAs for a specific CC / BWP in an uplink transmission (especially FR1) of a terminal, and ii) a method in which a terminal requests / acquires multiple TAs, and proposes subsequent terminal operations.

[0179] In this specification, " / " may be interpreted as "and", "or" or "and / or" depending on the context.

[0180] Suggestion 1

[0181] The terminal may be configured with a unified TCI corresponding to M / N>1 (in FR1 operation). For example, the terminal may receive configuration information for two or more unified TCI states from the base station. The two or more unified TCI states (two or more unified TCI states) may include at least one of i) two or more joint TCI states (two or more joint TCI states), ii) two or more DL TCI states (two or more UL TCI states), and / or iii) two or more UL TCI states (two or more UL TCI states).

[0182] When the UE is configured with two CORESET pool indexes in the CC / BWP for M-DCI based M-TRP operation from the base station, a UL related TCI state (e.g., DL / UL joint TCI state and / or DL / UL separate TCI state) connected / corresponding to each of the two CORESET pool indexes is configured / instructed. For example, the UE may receive configuration information for a plurality of CORESETs from the base station. A CORESET based on two CORESET pool indexes may be configured based on the configuration information. The UE may receive information indicating two UL related TCI states (e.g., two joint TCI states or two UL TCI states) connected / corresponding / associated with the two CORESET pool indexes from the base station. The information indicating the two UL related TCI states may be received based on at least one of a DCI, a MAC CE, or an RRC message.

[0183] Two TRP-specific TA values ​​can be concatenated / corresponding to the two UL related TCI states. Furthermore, the power control parameter sets set for each of the two UL related TCI states can be used as power control parameter sets for each target TRP in M-TRP UL transmission (e.g., M-TRP PUSCH / PUCCH repetition) (for S-DCI based M-TRP operation).

[0184] Specifically, since UL spatialRelationInfo (UL TCI) information is not applicable in FR1, the TCI state for setting / indicating two TA / PC parameter sets can be set / utilized as follows:

[0185] The reference RS corresponding to QCL type-D and / or UL spatialRelationInfo (UL TCI) may not be set in the two TCI states. For example, the referenceSignal field (in QCL-Info) may not be present in each TCI state. For example, the UE may not expect the referenceSignal field (in QCL-Info) to be set in each TCI state.

[0186] When a reference RS corresponding to QCL type-D or / and UL spatialRelationInfo (UL TCI) is configured in the two TCI states, the UE can omit / ignore / override the corresponding reference RS and perform UL transmission using only the TA / PC information corresponding to each target TRP (e.g., 1st / 2nd TCI or CORESET pool index 0 / 1).

[0187] As described above, the UE may determine TA / PC information corresponding to each target TRP (e.g., each TRP of the two target TRPs) based on the two TCI states. The UE may perform UL transmission for each target TRP based on the TA information / PC information. The UL transmission timing (e.g., uplink frame) for each target TRP may be determined based on TA information (e.g., TAG or TA value for TAG). The UL transmission power for each target TRP may be determined based on PC information (e.g., one or more PC parameters).

[0188] The TCI state can be set / indicated by RRC, MAC CE, and / or DCI, similar to the existing Rel-17 operation. When indicated by DCI, the base station can utilize i) DL( / UL) grant DCI or ii) DL( / UL) grant DCI without data scheduling. The base station can dynamically indicate the TCI state for each target TRP through the TCI field of the corresponding DCI. For example, when TCI indication by DCI is performed in a CORESET having a specific CORESET pool index as described above, the UE can utilize the corresponding TCI for reception / transmission of DL / UL channel / RS connected / corresponding to the corresponding CORESET pool index.

[0189] At this time, according to the Rel-17 standard, in the case of a TCI indication by grant DCI without data scheduling, the terminal can transmit an Ack ( / Nack) after receiving DCI (via PUCCH and / or PUSCH) (e.g., Use ACK / NACK mechanism analogous to that for SPS PDSCH release with both type-1 and type-2 HARQ-ACK codebook).

[0190] In FR1, when the above operation (i.e., TCI indication by grant DCI without data scheduling) is performed, the terminal can omit Ack ( / Nack) transmission. The omission of Ack ( / Nack) transmission takes into consideration the following technical points.

[0191] In Rel-17, the base station checks whether the TCI state including beam information (e.g., reference RS) for the terminal reception / transmission instructed by the DCI is normally received by the terminal. Then, the base station can use the base station's transmission / reception beam corresponding to the instructed TCI information for subsequent DL / UL transmission / reception. In contrast, an instruction for the TCI state not including the terminal's reception / transmission beam information is for the base station to set / instruct two TAs (two TAs) (e.g., two TAGs or two TAs corresponding to two TAGs) and two PCs (e.g., two parameter sets). Whether the instruction for the corresponding TA / PC is successfully transmitted is determined through the subsequent transmission of the terminal. Specifically, after the base station receives the subsequent UL transmission of the terminal, the base station can determine whether the TA / PC instruction by the preceding DCI is successfully transmitted to the terminal and the terminal performs UL transmission according to the instruction.

[0192] Therefore, in FR1, the terminal can omit transmitting an Ack ( / Nack) in response to an instruction for the TCI state (an instruction for the TCI state that does not include the terminal's reception / transmission beam information).

[0193] Furthermore, in the existing Rel-17 unified TCI framework, a concept such as beam application time (BAT) is defined, which indicates when a UE should change the corresponding reception / transmission beam from the time of receiving DCI. For example, a beamAppTime parameter can be set based on the PDSCH-config. The beamAppTime parameter indicates the first slot to which the unified TCI indicated by DCI is applied. The beamAppTime parameter can indicate the number of symbols (Y) (e.g., n1, n2, n4, n7, n14, n28, n42, n56, n70, n84, n98, n112, n224, n336). The first slot can be at least Y symbols after the last symbol of the acknowledgment of joint or separate DL / UL beam indication for the joint or separate DL / UL beam indication.

[0194] When the unified TCI framework is used to set / indicate TA / PC as described above, the BAT can be applied as a setting value for when UL TA / PC should be applied. Or / and, since the TCI state is not related to beam application, the UE does not expect the BAT to be set or expects the BAT value to be set to 0. As a specific example, a case can be assumed in which the unified TCI state for FR1 is indicated by DCI (e.g., DL grant DCI, UL grant DCI, DCI without DL grant, or DCI without UL grant). Since the indicated unified TCI state is not related to beam application, transmission of HARQ-ACK information for the DCI can be omitted. Since the transmission of the HARQ-ACK information is omitted, the time (e.g., symbol, slot, subframe, or frame) for application of the indicated unified TCI state cannot be determined by the beamAppTime parameter. In this case, even if the beamAppTime parameter is set, the UE may not use the corresponding beamAppTime parameter. In other words, the terminal may ignore the beamAppTime parameter. As an example, the time (e.g., symbol, slot, subframe, or frame) for application of the indicated unified TCI state may be determined without application of the beamAppTime parameter. As an example, the time for application of the indicated unified TCI state may be determined regardless of the beamAppTime parameter.

[0195] Suggestion 2

[0196] For two TRP-specific TA values ​​or / and two TRP-specific PC parameter sets, the base station can set separate parameter(s). Specifically, (in FR1 operation) two TRP-specific TA values ​​or / and two TRP-specific PC parameter sets can be set / linked / corresponded to the separately set parameter(s).

[0197] The additional parameter(s) may include a TRP-specific TA value. In this case, the parameter(s) may be set as follows: i) or ii).

[0198] i) A single parameter can be set that includes both the first TA value and the second TA value.

[0199] ii) Two parameters may be configurable: a first parameter may include a first TA value, and a second parameter may include a second TA value.

[0200] The additional parameter(s) may include a TRP-specific PC parameter set. In this case, the parameter(s) may be set as follows: i) or ii).

[0201] i) A single parameter can be set that includes both the first PC parameter set and the second PC parameter set.

[0202] ii) Two parameters may be configurable, the first parameter including a first set of PC parameters and the second parameter including a second set of PC parameters.

[0203] In the case of i), a specific CORESET pool index may be linked / corresponding to a specific TA value or / and a specific PC parameter set in the single parameter. For example, CORESET pool index 0 may be linked to a first TA / first PC parameter set value, and CORESET pool index 1 may be linked to a second TA / second PC parameter set value.

[0204] In the case of ii), a specific CORESET pool index and a specific parameter among the two parameters may be linked / corresponding. For example, CORESET pool index 0 may be linked to the first parameter, and CORESET pool index 1 may be linked to the second parameter.

[0205] As described above, a first TA / PC parameter set value and a second TA / PC parameter set value may be set in specific parameter(s) and linked to a specific CORESET pool index. When a UL transmission is associated with / corresponding to a specific CORESET pool index, the UE may perform UL transmission using a TRP-specific TA value and / or a TRP-specific PC parameter set linked to the CORESET pool index.

[0206] Furthermore, for flexible configuration, in each CORESET(group) configuration, a TRP-specific TA value or / and the two TRP-specific PC parameter sets corresponding to the two TA values ​​can be configured / concatenated / mapped / updated, so that the UE can perform UL transmission using the TRP-specific TA value or / and PC parameter set configured in the corresponding CORESET during UL transmission related to a specific CORESET(group).

[0207] In the above embodiment, the expression "(a particular parameter and another parameter) can be connected / corresponding" means that a particular parameter can be associated with another parameter via RRC / MAC CE / DCI signaling.

[0208] As long as the embodiments of Proposal 1 and Proposal 2 are not mutually exclusive, the embodiments of Proposal 1 and Proposal 2 can be combined and applied to the operation between the base station and the terminal. For example, the unified TCI setting operation (Proposal 1) and the operation in which separate parameter(s) are set (Proposal 2) cannot be combined, but the other embodiments can be combined and applied. Specifically, the embodiments of Proposal 1 and Proposal 2 related to two TRP-specific TA values ​​(two TRP-specific PC parameter sets) can be combined and applied to the terminal / base station operation.

[0209] Multiple TA acquisition

[0210] In order to set the above-mentioned multiple TA values, it is necessary to determine how the base station will request / acquire multiple TA values. Below, we propose a method for the base station / terminal to acquire multiple TA values ​​and the terminal operation. Specifically, in the following Proposal 3, we propose a method for the terminal to acquire two TAs (two TA acquisition) without RACH enhancement and a TA setting method for the base station, and in Proposal 4, we propose a method for the terminal to acquire two TAs via RACH enhancement and a TA setting method for the base station.

[0211] Hereinafter, when a first TA or a second TA is linked / corresponding to a particular CORESET pool index, it may mean that the first TA or / and the second TA are linked / corresponding to a first TCI state or / and a second TCI state (for common beam operation in the unified TCI framework).

[0212] Hereinafter, the first TA and the second TA may refer to the first / second TA values ​​managed for setting two TRP-specific TA values ​​in a specific TAG (i.e., one TAG), or the first TA and the second TA may refer to the first TA value and the second TA value managed corresponding to different TAGs (first TAG, second TAG) for the same CC(set).

[0213] Suggestion 3

[0214] In the following, two methods for performing TA acquisition without RACH enhancement and a method for setting TA in a base station are described.

[0215] Proposal 3-1

[0216] The UE can transmit RACH in single (and / or primary / first) TA in a RACH transmission procedure including initial access (e.g. PDCCH ordered RACH, RACH transmitted due to expiration of TA timer, etc.). The base station can measure the first / second TA by receiving the subsequent SRS of the UE. That is, a method of setting / indicating an implicit / explicit association / correspondence between a specific SRS resource (set) and a specific CORESET pool index is proposed.

[0217] The following operations can be performed for an aperiodic SRS resource (set) corresponding to dynamic scheduling: The UE can receive an SRS triggering DCI in a CORESET having a specific CORESET pool index. In this case, the aperiodic SRS resource (set) transmitted by the UE can be linked / corresponded to the specific CORESET pool index.

[0218] The following operations can be performed in relation to periodic / semi-persistent SRS resource (set) transmitted by the UE via RRC / MAC CE signaling: The base station can explicitly set / connect / associate a CORESET pool index associated with a specific SRS resource (set). This allows the UE / base station to know which CORESET pool index a specific SRS resource (set) is connected to / corresponding to.

[0219] As a result, the base station / terminal can understand that a specific P / SP / AP SRS resource (set) transmitted by the terminal is associated / corresponding to a specific CORESET pool index. In other words, the base station can identify the CORESET pool index associated / corresponding to a specific P / SP / AP SRS resource (set) transmitted by the terminal. The base station can measure the first TA and / or the second TA via the SRS transmitted by the terminal.

[0220] According to one embodiment, the first ( / primary) TA can be obtained via the existing RACH procedure, and the second TA can be obtained via the SRS associated with CORESET pool index 1 as described above.

[0221] Proposal 3-2

[0222] The base station can measure the first TA or / and the second TA associated / corresponding to a specific CORESET pool index according to Proposal 3-1. The base station can set / indicate a TRP specific TA value (e.g., the first / second TA) using the enhanced RAR MAC CE format or / and the enhanced TA command MAC CE.

[0223] As an example, the base station may configure a target CORESET pool index in the enhanced MAC CE format. As a result, a TA value related to / corresponding to the CORESET pool index may be set / indicated. As a specific example, the enhanced MAC CE format may include a field indicating a target CORESET pool index.

[0224] As an example, the base station may configure the first / second TCI corresponding to M / N>1 for TRP-specific common beam operation as a target in the enhanced MAC CE format. Thus, a TA value related / corresponding to the first / second TCI may be set / indicated. As a specific example, the enhanced MAC CE format may include a field indicating a target TCI (e.g., a first TCI state or a second TCI state).

[0225] As an example, the base station may configure the enhanced MAC CE format with a specific joint and / or separate UL TCI state(s) index as a target. Thus, a TA value to be applied to the corresponding TCI state(s) may be set / indicated. Specifically, the TA value in the MAC CE format for setting / indicating the second TA value may be set / defined / indicated with a different TA granularity or / and value range than the first TA value in the same MAC CE format. This is because, in the M-TRP operation, the difference between the UL TA values ​​of different TRPs may be greater than the CP length from the DL timing reference. (When using the same number of bits as the first TA value) The granularity of the second TA value may be expressed as a step size slightly larger than the first TA value. (When using the same number of bits as the first TA value) The value range of the second TA value may be expressed as a value range slightly larger than the first TA value.

[0226] As described above, the base station can set / instruct the first / second TA for a specific target CORESET pool index / target common TCI / target TCI state(s). In UL channel / RS (especially SRS in Proposal 3-1) transmission related to the target CORESET pool index / target common TCI / target TCI state(s), the terminal can perform uplink transmission by applying the set / instructed first / second TA value.

[0227] After setting / indicating a TRP-specific TA according to Proposal 3-2, the base station can measure the TRP-specific SRS transmission of the terminal based on Proposal 3-1 and perform update / activation of the TRP-specific TA value.

[0228] Suggestion 4

[0229] In the following, two methods for performing TA acquisition via RACH enhancement and a method for setting TA in a base station will be described.

[0230] Proposal 4-1

[0231] Methods are envisaged to support TRP specific RACH transmission for TRP specific TA measurements.

[0232] The base station may perform grouping on SSBs (SS / PBCH blocks) that the terminal uses for RACH transmission. The base station may link / associate a specific SSB group with a specific CORESET pool index. For example, SSBs corresponding to SSB indexes 0 to 31 are linked / associated with CORESET pool index 0, and SSBs corresponding to SSB indexes 32 to 64 are linked / associated with CORESET pool index 1. Here, the SSB index may be the SS / PBCH index of the SS / PBCH block.

[0233] Based on the grouping, the base station may configure / instruct to use a specific SSB index when configuring / instructing to transmit a (PDCCH ordered) RACH to the terminal. The RACH may mean a random access preamble. For example, the base station may transmit DCI (e.g., DCI format 1_0) including information related to the PDCCH order to the terminal. A random access procedure is initiated by the PDCCH order. The terminal transmits a random access preamble to the base station. The information related to the PDCCH order may include an SS / PBCH index. The SS / PBCH index may be linked / associated with a specific CORESET pool index. The random access preamble is transmitted based on the SS / PBCH index.

[0234] By having the terminal transmit a RACH corresponding to the corresponding SSB (based on the specific SSB index), the base station can use the RACH to measure a TRP-specific TA associated / corresponding to each CORESET pool index.

[0235] According to one embodiment, when the base station instructs (PDCCH ordered) RACH transmission, the terminal may be instructed / scheduled to transmit multiple RACHs by transmitting a single PDCCH (e.g., single DCI) so that the terminal can transmit RACHs associated with each CORESET pool index. As a specific example, the single DCI may include information about the PDCCH order. In this case, the information about the PDCCH order may include two SS / PBCH indexes. The terminal may transmit two random access preambles to the base station based on the two SS / PBCH indexes. In this manner, overhead / delay can be reduced by transmitting a single PDCCH, and the terminal may be instructed to transmit all RACHs for each TRP. The base station may perform TA measurement for each TRP at once.

[0236] According to an embodiment, the connection / correspondence relationship between the specific SSB group and a specific CORESET pool index may be set / defined / specified by connecting / corresponding a specific CORESET pool index to a PRACH preamble index / RACH occasion / PRACH mask index. Specifically, DCI (e.g., DCI Format 1_0) related to a PDCCH order may include a Random Access Preamble index, an SS / PBCH index, and a PRACH Mask index. If the value of the Random Access Preamble index is not zero, the PRACH Mask index indicates a RACH occasion related to an SS / PBCH indicated by the SS / PBCH index. The specific CORESET pool index may be set to be connected / corresponded to at least one of a PRACH preamble index, a PRACH mask index, or a RACH occasion.

[0237] Furthermore, if a connection / correspondence between a specific SSB group and a specific CORESET pool index is defined / configured, the following operations are performed: The base station may schedule RACH transmission of the terminal according to the PDCCH order via a CORESET having a specific CORESET pool index. In this case, the terminal may perform (or may be forced to perform) RACH transmission corresponding to the SSB connected / corresponding to the specific CORESET pool index (even if there is no SSB index indication in the PDCCH). In other words, the terminal may perform RACH transmission based on the CORESET pool index of the CORESET in which DCI (related to the PDCCH order) is received.

[0238] The RACH transmission in Proposal 4-1 may not be utilized in the RACH transmission during initial access.

[0239] Even if the terminal performs a TRP-specific RACH transmission as described above, the terminal performs all operations based on a specific SSB in the RA procedure, and therefore does not change the TA value during UL transmission in the corresponding RA procedure. That is, the terminal performs UL transmission using the same TA value. The RA procedure may include a 4-step RACH procedure and / or a 2-step RACH procedure. For example, a 4-step RACH procedure (e.g., contention-based RACH) may include operations of transmitting Msg1 (preamble), receiving Msg2 (RAR), transmitting Msg3 (PUSCH), and receiving Msg4 (contention-resolution). For example, a 2-step RACH procedure may include operations of transmitting MsgA (preamble and PUSCH) and receiving MsgB (RAR).

[0240] Proposal 4-2

[0241] Below, we explain the method for managing the TRP-specific TA timer.

[0242] According to the existing TA maintenance operation, when a timer corresponding to a PTAG (Primary Timing Advance Group) expires due to a timeAlignmentTimer (per TAG), the UE can release the UL transmission and transmit a RACH. This embodiment proposes a method for managing the timeAlignmentTimer corresponding to the TA timer in a TRP-specific manner.

[0243] The UE may manage up to two TA timers corresponding to CORESET pool index 0, 1, or / and the first and second TA values ​​in a single TAG. Here, each of the two timers may be set in different TAGs for different TRPs.

[0244] According to the existing operation, when the TA timer expires, the UE transmits a RACH corresponding to any SSB (e.g., an SSB based on one of the SSB indexes). In contrast, according to the present embodiment, when the TA timer associated / corresponding to a specific CORESET pool index and / or a specific first / second TA value expires, the UE can transmit a RACH based on the CORESET pool index associated / corresponding to the expired TA timer. That is, a RACH corresponding to an SSB connected / corresponding to the corresponding CORESET pool index can be transmitted.

[0245] With this operation, when the TA value corresponding to a specific TRP expires, the terminal can transmit a RACH for the corresponding TRP. The base station can measure the TA value of the terminal from the corresponding TRP and set / instruct / update the TRP-specific TA value to the terminal (as in Proposal 3-2).

[0246] In addition, in the existing operation, when the timer corresponding to the PTAG expires, a UL OOS (Out of Synch) operation is performed, but when two TRP-specific timers corresponding to the first and second TAs are managed as in Proposal 4-2, it can be assumed that one timer expires and the other does not. In such a case, the UE may not need to perform all of the already defined UL OOS operations (e.g., not perform the RRC release operation, etc.). If both timers expire, the UE must perform all of the already defined UL OOS operations.

[0247] Proposal 4-3

[0248] The following describes a method for a base station to transmit an RAR corresponding to a TRP-specific RACH transmission of a terminal.

[0249] According to the proposal 4-1 or / and 4-2, a specific RACH transmission of a terminal corresponds to a specific SSB. A specific RACH transmission and a specific CORESET pool index can naturally have a correspondence relationship due to the correspondence relationship between the SSB index and the CORESET pool index. A method is proposed in which the base station transmits an RAR to the TRP-specific for such a TRP-specific RACH transmission of a terminal.

[0250] The base station may receive a specific RACH having a corresponding relationship with a specific CORESET pool index. The base station may transmit an RAR for a corresponding RACH to a terminal based on a part of CORESETs among the CORESETs having the specific CORESET pool index. For example, the part of CORESETs may be a CORESET having a lowest index among the CORESETs having the corresponding CORESET pool index.

[0251] In the existing standard operation, a terminal may receive a configuration for a type1-PDCCH CSS set (Common Search Space set) for receiving an RAR from a base station. Specifically, the type1-PDCCH CSS set may be configured based on ra-searchspace of a PDCCH-ConfigCommon IE. For example, the RAR may be received based on monitoring of PDCCH candidates in a Search Space set (SS set).

[0252] Proposal 4-3 proposes a method that enables a terminal to receive a TRP-specific RAR not only via a type 1-PDCCH CSS set but also via a separate USS set (UE-specific Search Space set).

[0253] According to one embodiment, a method of linking / setting the separate USS set and a CORESET for receiving the TRP-specific RAR may be considered. Each USS set may be linked / corresponding to a CORESET having a different CORESET pool index.

[0254] According to one embodiment, the base station may transmit an RAR for a RACH for measuring the first / primary (and / or corresponding to CORESET pool index 0) TA value via the existing type1-PDCCH CSS set. The base station may transmit an RAR for a RACH for measuring the second (and / or corresponding to CORESET pool index 1) TA value by configuring the separate USS set. When the USS set is used for receiving a TRP-specific RAR as described above, a separate RNTI for receiving the TRP-specific RAR may be configured in the terminal.

[0255] According to one embodiment, a terminal may receive a TRP-specific RAR based on a configuration of multiple CSS sets (e.g., a configuration of two CSS sets considering two TRPs). The two CSS sets may be associated / corresponding to CORESETs having different CORESET pool indexes.

[0256] The MAC CE format transmitted via such a TRP-specific RAR may include all the settings / instructions for multiple TA values ​​in a specific CC / BWP as in Proposal 3-2, or the MAC CE format transmitted via the TRP-specific RAR may include only the settings / instructions for the TA value associated / corresponding to the CORESET pool index in which the corresponding RAR is transmitted.

[0257] For a TA value associated with a specific CORESET pool index indicated via this MAC CE format, the UE can specify / define a DL timing reference based on reception of the RAR (UL grant DCI) transmitted in a CORESET having the corresponding CORESET pool index. The UE can apply the TA value indicated from the DL timing reference. In a non-ideal backhaul scenario (e.g., a scenario where there is no coordination between TRPs) in the M-DCI based M-TRP situation, the DL timing references between TRPs may differ significantly. In this case, the base station can indicate to the UE an appropriate TRP-specific TA value for the DL timing reference for each TRP through the above-mentioned operation.

[0258] The embodiments of Proposals 3 to 4 can be combined with the embodiments of Proposal 1 and Proposal 2 to be applied to the operation between the base station and the terminal, unless they are mutually exclusive. For example, the operation of acquiring two TAs without RACH enhancement (Proposal 3) and the operation of acquiring two TAs via RACH enhancement (Proposal 4) cannot be combined, but the other embodiments can be combined and applied. Specifically, the embodiments of Proposal 3 and Proposal 4 related to two TRP-specific TA values ​​can be combined and applied to the terminal / base station operation.

[0259] In the following, a signaling procedure based on the above embodiment will be specifically described.

[0260] An example of a terminal (or base station) operation based on at least one of the above-described embodiments (eg, at least one of Proposal 1 to Proposal 4) is as follows.

[0261] 1) The terminal receives (sends) unified TCI related setting information and / or TRP-specific TA / PC related setting information.

[0262] The setting information is based on the contents of Proposal 1 to Proposal 4.

[0263] The terminal transmits (receives) SRS and / or RACH based on Proposal 3 or Proposal 4 depending on the base station configuration.

[0264] After receiving the SRS and / or RACH and measuring the TRP-specific TA, the base station can set / instruct the TRP-specific TA value to the terminal via MAC CE (RAR and / or TA command) based on Proposal 3 to Proposal 4.

[0265] 2) The terminal receives (sends) a message to schedule a TRP-specific UL transmission.

[0266] The message may be based on at least one of a first PDCCH (first DCI) and / or a second PDCCH (first DCI).

[0267] The message is associated with a particular CORESET pool index and / or a particular CORESET(group).

[0268] 3) The terminal transmits (receives) UL channel / RS using TRP-specific TA / PC setting information based on the message.

[0269] The UL channel / RS may be based on at least one of an SRS, a PUSCH, a PUCCH, or a random access preamble, and the UL channel / RS transmission may be performed based on the contents of Proposal 1 to Proposal 4.

[0270] 4) The terminal can manage the TRP-specific TA timer based on the contents of Proposal 4.

[0271] The above operations of the terminal / base station are merely examples, and each operation (or step) is not necessarily required. Depending on the implementation method of the terminal / base station, operations related to uplink transmission using the TRP-specific TA / PC of the terminal according to the above embodiments may be omitted or added.

[0272] In an implementation aspect, the operation of the base station / terminal according to the above-mentioned embodiments (e.g., operation related to uplink transmission utilizing a TRP-specific TA / PC of a terminal based on at least one of Proposal 1 to Proposal 4) can be processed by the apparatus of FIG. 5 described below (e.g., processors 110, 210 of FIG. 5).

[0273] In addition, the operation of the base station / terminal according to the above-mentioned embodiments (e.g., operation related to uplink transmission using a TRP-specific TA / PC of a terminal based on at least one of Proposals 1 to 4) may also be stored in a memory (e.g., 140, 240 in FIG. 5) in the form of instructions / programs (e.g., instructions, executable codes) for driving at least one processor (e.g., 110, 210 in FIG. 5).

[0274] Hereinafter, the above-mentioned embodiment will be described in detail from the viewpoint of the operation of a terminal and a base station with reference to Figures 3 and 4. The methods described below are merely divided for the convenience of explanation, and it is obvious that some components of one method can be replaced with some components of another method or can be combined with each other to be applied.

[0275] FIG. 3 is a flowchart illustrating a method performed by a terminal in a wireless communication system according to an embodiment of the present specification.

[0276] As shown in FIG. 3, a method performed by a terminal in a wireless communication system according to one embodiment of this specification includes a configuration information receiving step (S310), a DCI receiving step (S320), a random access preamble transmitting step (S330), and a random access response receiving step (S340).

[0277] At S310, the terminal receives configuration information related to a plurality of control resource sets (COntrol REsource SETs, CORESETs) from the base station.

[0278] Based on the configuration information, a CORESET (e.g., a first CORESET and a second CORESET) based on a first control resource set pool index (CORESET pool index) and a second control resource set pool index (CORESET pool index) can be configured. In other words, based on the configuration information, a CORESET based on two different control resource set pool indexes (CORESET pool indexes) can be configured.

[0279] At S320, the terminal receives downlink control information (DCI) from the base station. The DCI may include information about a physical downlink control channel (PDCCH) order.

[0280] For example, the DCI may be DCI format 1_0. The information (field) related to the PDCCH order may include at least one of i) a Random Access Preamble index and ii) an SS / PBCH index. The SS / PBCH index field may indicate an SS / PBCH (or an SSB index) used to determine a RACH occasion for a PRACH transmission (i.e., a random access preamble transmission).

[0281] According to an embodiment, the information related to the PDCCH order may include a Synchronization Signal / Physical Broadcast Channel Block index (SSB index), where the SSB index may be an SS / PBCH index of an SS / PBCH block. As an example, the information related to the PDCCH order may include one or more SSB indices.

[0282] A random access procedure may be initiated by the PDCCH order. For example, a random access procedure may be initiated by the PDCCH order to establish a timing advance for a Timing Advance Group. That is, DCI associated with the PDCCH order is transmitted from the base station to the terminal.

[0283] As an example, the random access procedure may be a Type-1 random access procedure (4-step RA) or a Type-2 random access procedure (2-step RA).

[0284] The Type-1 random access procedure may include a random access preamble transmission (Msg1) on a physical random access channel (PRACH), a random access response (RAR) reception (Msg2), a PUSCH transmission (Msg3) scheduled by a UL grant of the RAR, and a PDSCH (Msg4) for contention resolution. When the random access procedure is a contention-free random access (CFRA), the Msg3 transmission and Msg4 reception operations are omitted.

[0285] The Type-2 random access procedure may include transmitting a random access preamble and a PUSCH (MsgA) and receiving an RAR (MsgB).

[0286] At S330, the terminal sends a random access preamble to the base station, where the random access preamble may be based on Msg1 of the Type-1 random access procedure or MsgA of the Type-2 random access procedure.

[0287] According to an embodiment, the random access preamble may be transmitted based on the SSB index(es). This embodiment may be based on Proposal 4. The SSB index may refer to the SSB index(es) indicated by DCI (e.g., DCI format 1_0) including information related to the PDCCH order.

[0288] Specifically, a RACH occasion for transmitting the random access preamble is determined based on the SSB index. The RACH occasion (or PRACH occasion) refers to a time-frequency domain region for transmitting the random access preamble. The SSB and the RACH occasion (RO) based on the SSB index have a mapping relationship. As an example, an upper layer parameter ssb-perRACH-OccasionAndCB-PreamblesPerSSB can indicate i) the number of SSBs mapped to one RACH occasion (RO) and ii) the preamble index mapped to one SSB.

[0289] The SSB index is associated with the first CORESET pool index or the second CORESET pool index. The SSB index may be a first SSB index or a second SSB index.

[0290] According to one embodiment, multiple random access preambles associated with multiple CORESET pool indexes (TRPs) are transmitted based on DCI associated with the PDCCH order.

[0291] As an example, the SSB index may be based on one or more SSB indexes. Based on the one or more SSB indexes including i) a first SSB index associated with the first CORESET pool index and ii) a second SSB index associated with the second CORESET pool index, a first random access preamble may be transmitted based on the first SSB index, and a second random access preamble may be transmitted based on the second SSB index. Based on the first / second random access preamble being transmitted, the terminal may receive a first / second random access response from the base station.

[0292] At S340, the terminal receives a Random Access Response (RAR) from the base station. The Random Access Response (RAR) may include a Timing Advance Command. The RAR may be based on Msg2 of the Type-1 random access procedure or MsgB of the Type-2 random access procedure.

[0293] For example, the RAR may be received based on the PDCCH and PDSCH. The terminal detects DCI (e.g., DCI format 1_0) transmitted via the PDCCH in a window configured for a random access procedure. The window may be configured in slot units (e.g., one or more slots) by a higher layer parameter ra-ResponseWindow. The terminal receives a transport block corresponding to the PDSCH scheduled by the DCI in the window. The RAR may be based on the transport block. The RAR may refer to the MAC RAR in FIG. 1.

[0294] The detection (reception) of the DCI may be based on monitoring PDCCH candidates. According to one embodiment, the RAR may be received based on monitoring PDCCH candidates in a Search Space set (SS set). This embodiment may be based on Proposal 4-3.

[0295] The SS set may be based on a common search space set (CSS set) or a UE-specific search space set (USS set). For example, the CSS set may be a Type1-PDCCH CSS set set by a higher layer parameter ra-SearchSpace.

[0296] The SS set may be separately configured for receiving a RAR corresponding to each TRP (i.e., each CORESET pool index). As an example, the SS set may be associated with one or more CORESETs based on the first CORESET pool index or the second CORESET pool index. The SS set may be i) a USS set (or a CSS set) associated with one or more first CORESETs having the first CORESET pool index, or ii) a USS set (or a CSS set) associated with one or more second CORESETs having the second CORESET pool index.

[0297] The method may further include receiving SSBs. Specifically, the terminal receives synchronization signal / physical broadcast channel blocks (SS / PBCH blocks, SSBs) from the base station based on a plurality of SSB indexes. The receiving SSBs may be performed before S310 or S320.

[0298] The multiple SSB indexes can be classified into groups corresponding to multiple TRPs (multiple CORESET pool indexes). This embodiment is based on Proposal 4-1.

[0299] As an example, the multiple SSB indexes may include an SSB index (e.g., a first SSB index) belonging to a first group associated with a first CORESET pool index and an SSB index (e.g., a second SSB index) belonging to a second group associated with a second CORESET pool index.

[0300] According to one embodiment, the plurality of SSB indexes may include i) a first SSB index associated with the first CORESET pool index and ii) a second SSB index associated with the second CORESET pool index.

[0301] The SSB index may be i) one of the first SSB indexes or ii) one of the second SSB indexes. The SSB index may refer to an SSB index indicated by a DCI (e.g., DCI format 1_0) including information related to the PDCCH order.

[0302] The grouping of the plurality of SSB indexes may be performed in ascending or descending order of index values ​​(ie, SSB index values).

[0303] For example, the grouping may be performed in ascending order of SSB index. Based on the plurality of SSB indexes including SSB index 0 to SSB index 63, the first SSB index may include SSB index 0 to SSB index 31, and the second SSB index may include SSB index 32 to SSB index 63.

[0304] As described above, when there are two CORESET pool indices corresponding to a TRP, the first group may be SSB index 0 to 31 (or SSB index 32 to 63), and the second group may be SSB index 32 to 63 (or SSB index 0 to 31).

[0305] The grouping of the multiple SSB indexes may be performed regardless of the order of the index values ​​(ie, the SSB index values).

[0306] For example, when there are two CORESET pool indexes corresponding to a TRP, the first group may include even SSB indexes (e.g., SSB indexes 0, 2, 4..62) and the second group may include odd SSB indexes (e.g., SSB indexes 1, 3, 5..63). Conversely, the first group may include odd SSB indexes and the second group may include even SSB indexes.

[0307] According to one embodiment, the Timing Advance command indicates an index associated with a Timing adjustment (see FIG. 1, Tables 4 and 5). The index associated with the Timing adjustment is the index value T A Based on the index related to the timing adjustment, N TA can be indicated.

[0308] The TA is as shown in Table 1. JPEG2025514184000023.jpg510. The TA may be a TRP specific TA (e.g., a first TA or a second TA). Specifically, the TA is associated with a first Timing Advance Group (TAG) or a second Timing Advance Group (TAG). The first TAG (or first TAG ID) is associated with the first CORESET pool index, and the second TAG (or second TAG ID) is associated with the second CORESET pool index.

[0309] According to one embodiment, the Time Alignment Timer associated with the TA may be a first Time Alignment Timer associated with the first TAG or a second Time Alignment Timer associated with the second TAG. This embodiment is based on Proposal 4-2.

[0310] If the Time Alignment Timer does not run, the terminal will not perform any other uplink transmissions except for the transmission of random access preambles (Msg1 and MsgA).

[0311] The first TAG and / or the second TAG may be associated with a Primary Timing Advance Group (PTAG). As an example, the first TAG (or the second TAG) may be the PTAG and the second TAG (or the first TAG) may be a Secondary Timing Advance Group (STAG). As an example, the first TAG may be a first PTAG and the second TAG may be a second PTAG.

[0312] According to the conventional method, when the TA Alignment Timer corresponding to the PTAG expires, a UL OOS (Out Of Sync) operation is performed. However, if at least one of the multiple TA Alignment Timers has not expired, the operation may be unnecessary. Therefore, the UL OOS operation is limitedly performed when all the TA Alignment Timers corresponding to the multiple TRPs have expired.

[0313] As an example, the first and / or second Time Alignment Timers may be associated with a Primary Timing Advance Group (PTAG), and the configuration for uplink transmission may be released based on the expiration of the first and / or second Time Alignment Timers. Thereafter, a random access preamble (e.g., a first random access preamble and / or a second random access preamble) is transmitted based on a first SSB index and / or a second SSB index associated with the first and / or second Time Alignment Timers.

[0314] The configuration for the uplink transmission may include at least one of a Physical Uplink Control Channel (PUCCH) configuration, a Sounding Reference Signal (SRS) configuration, a Physical Uplink Shared Channel (PUSCH) resource(s) and / or a configured uplink grant(s).

[0315] For example, based on expiration of a Time Alignment Timer (e.g., the first Time Alignment Timer or the second Time Alignment Timer) associated with the TA, a random access can be transmitted based on an SSB index (e.g., the first SSB index or the second SSB index) associated with the expired Time Alignment Timer (e.g., the first Time Alignment Timer or the second Time Alignment Timer). Specifically, the SSB index associated with the expired Time Alignment Timer is associated with the first CORESET pool index or the second CORESET pool index. In this case, the random access preamble may be transmitted based on a random access procedure initiated by the UE (e.g., UE initiated RACH procedure) rather than in a PDCCH order.

[0316] The operations based on S310 to S340 and the SSB reception stage described above may be implemented by the apparatus of Fig. 5. For example, the terminal 200 may control one or more transceivers 230 and / or one or more memories 240 to perform operations based on S310 to S340 and the SSB reception stage.

[0317] The above-described embodiment will now be described in detail from the viewpoint of the operation of the base station.

[0318] S410 to S440 and an SSB transmission step described below correspond to S310 to S340 and an SSB reception step described in FIG. 3. In consideration of the correspondence, duplicated descriptions will be omitted. That is, a detailed description of a base station operation described below may be replaced with the description / embodiment of FIG. 3 corresponding to the corresponding operation. As an example, the description / embodiment of S310 to S340 in FIG. 3 may be additionally applied to the base station operation of S410 to S440 described below. As an example, the description / embodiment of the SSB reception step in FIG. 3 corresponding to the SSB transmission step described below may be additionally applied to the SSB transmission step described below.

[0319] FIG. 4 is a flowchart illustrating a method performed by a base station in a wireless communication system according to another embodiment of the present disclosure.

[0320] As shown in FIG. 4, a method performed by a base station in a wireless communication system according to another embodiment of the present specification includes a configuration information transmitting step (S410), a DCI transmitting step (S420), a random access preamble receiving step (S430), and a random access response transmitting step (S440).

[0321] At S410, the base station transmits configuration information regarding a plurality of control resource sets (COntrol REsource SETs, CORESETs) to the terminal.

[0322] At S420, the base station transmits downlink control information (DCI) to the terminal.

[0323] At S430, the base station receives a random access preamble from the terminal.

[0324] At S440, the base station transmits a Random Access Response (RAR) to the terminal.

[0325] The method may further include an SSB transmission step, in which the base station transmits synchronization signal / physical broadcast channel blocks (SS / PBCH blocks, SSBs) to the terminal based on a plurality of SSB indexes. The SSB transmission step may be performed before S410 or S420.

[0326] The operations based on S410 through S440 and the SSB transmission step described above may be implemented by the apparatus of Figure 5. For example, the base station 100 may control one or more transceivers 130 and / or one or more memories 140 to perform the operations based on S410 through S440 and the SSB transmission step.

[0327] An apparatus to which the embodiments of the present specification can be applied (an apparatus that realizes the methods / operations according to the embodiments of the present specification) will be described below with reference to FIG.

[0328] FIG. 5 is a diagram illustrating the configuration of a first device and a second device according to an embodiment of the present specification.

[0329] The first device 100 may include a processor 110, an antenna unit 120, a transceiver 130, and a memory 140.

[0330] The processor 110 performs baseband-related signal processing and may include an upper layer processing unit 111 and a physical layer processing unit 115. The upper layer processing unit 111 can process operations of the MAC layer, the RRC layer, or higher layers. The physical layer processing unit 115 can process operations of the PHY layer. For example, when the first device 100 is a base station device in base station-terminal communication, the physical layer processing unit 115 can perform uplink reception signal processing, downlink transmission signal processing, etc. For example, when the first device 100 is a first terminal device in terminal-terminal communication, the physical layer processing unit 115 can perform downlink reception signal processing, uplink transmission signal processing, sidelink transmission signal processing, etc. In addition to performing baseband-related signal processing, the processor 110 can also control the overall operation of the first device 100.

[0331] The antenna unit 120 may include one or more physical antennas, and when multiple antennas are included, MIMO transmission and reception may be supported. The transceiver 130 may include an RF (Radio Frequency) transmitter and an RF receiver. The memory 140 may store information processed by the processor 110, software related to the operation of the first device 100, an operating system, applications, etc., and may include components such as a buffer.

[0332] The processor 110 of the first device 100 can be configured to implement the operation of a base station in base station-terminal communication (or the operation of a first terminal device in terminal-terminal communication) in the embodiments described in this disclosure.

[0333] The second device 200 may include a processor 210 , an antenna unit 220 , a transceiver 230 , and a memory 240 .

[0334] The processor 210 performs baseband-related signal processing and may include an upper layer processing unit 211 and a physical layer processing unit 215. The upper layer processing unit 211 can process operations of the MAC layer, the RRC layer, or higher layers. The physical layer processing unit 215 can process operations of the PHY layer. For example, when the second device 200 is a terminal device in base station-terminal communication, the physical layer processing unit 215 can perform downlink reception signal processing, uplink transmission signal processing, etc. For example, when the second device 200 is a second terminal device in terminal-terminal communication, the physical layer processing unit 215 can perform downlink reception signal processing, uplink transmission signal processing, sidelink reception signal processing, etc. In addition to performing baseband-related signal processing, the processor 210 can also control the overall operation of the second device 200.

[0335] The antenna unit 220 may include one or more physical antennas, and when multiple antennas are included, MIMO transmission and reception may be supported. The transceiver 230 may include an RF transmitter and an RF receiver. The memory 240 may store information processed by the processor 210, software related to the operation of the second device 200, an operating system, applications, etc., and may include components such as buffers.

[0336] The processor 210 of the second device 200 may be configured to implement the operation of a terminal in base station-terminal communication (or the operation of a second terminal device in terminal-terminal communication) in the embodiments described in this disclosure.

[0337] In the operation of the first device 100 and the second device 200, the matters described in the examples of the present disclosure regarding the base station and terminal in base station-terminal communication (or the first terminal and second terminal in terminal-terminal communication) can be equally applied, and duplicate explanations will be omitted.

[0338] Here, the wireless communication technology realized by the devices 100 and 200 of the present disclosure may include not only LTE, NR, and 6G, but also Narrowband Internet of Things (NB-IoT) for low power communication. For example, the NB-IoT technology is an example of a Low Power Wide Area Network (LPWAN) technology, and can be realized by standards such as LTE Cat NB1 and / or LTE Cat NB2, and is not limited to the above names.

[0339] Additionally or alternatively, the wireless communication technology implemented in the devices 100 and 200 of the present disclosure may perform communication based on the LTE-M technology. For example, the LTE-M technology is an example of an LPWAN technology and is referred to by various names such as eMTC (enhanced Machine Type Communication). For example, the LTE-M technology may be implemented by at least one of various standards such as 1) LTE CAT 0, 2) LTE Cat M1, 3) LTE Cat M2, 4) LTE non-BL (non-Bandwidth Limited), 5) LTE-MTC, 6) LTE Machine Type Communication, and / or 7) LTE M, and is not limited to the above names.

[0340] Additionally or alternatively, the wireless communication technology implemented in the devices 100 and 200 of the present disclosure may include at least one of ZigBee (registered trademark), Bluetooth (registered trademark), and Low Power Wide Area Network (LPWAN), which consider low power communication, but are not limited to the above names. For example, ZigBee technology can create personal area networks (PANs) related to small / low-power digital communication based on various standards such as IEEE 802.15.4, and can be called by various names.

Claims

1. 1. A method performed by a terminal in a wireless communication system, comprising: receiving configuration information related to a plurality of control resource sets (CORESETs) from a base station; configuring a CORESET based on a first control resource set pool index (CORESET pool index) and a second control resource set pool index (CORESET pool index) based on the configuration information; receiving downlink control information (DCI) from the base station, the DCI including information on a physical downlink control channel (PDCCH) order, and initiating a random access procedure according to the PDCCH order; transmitting a random access preamble to the base station; and receiving a Random Access Response (RAR) from the base station, The information on the PDCCH order includes a synchronization signal / physical broadcast channel block index (SSB index), The random access preamble is transmitted based on the SSB index; The random access response (RAR) includes a timing advance command (Timing Advance Command), The method, wherein the SSB index is related to the first CORESET pool index or the second CORESET pool index.

2. 2. The method of claim 1, further comprising receiving synchronization signal / physical broadcast channel blocks (SS / PBC blocks, SSBs) from the base station based on a plurality of SSB indices.

3. 3. The method of claim 2, wherein the plurality of SSB indexes includes: i) a first SSB index associated with the first CORESET pool index; and ii) a second SSB index associated with the second CORESET pool index.

4. 4. The method of claim 3, wherein the SSB index is i) one of the first SSB indexes or ii) one of the second SSB indexes.

5. The method of claim 1, wherein the RAR is received based on monitoring PDCCH candidates in a search space set (SS set).

6. The method of claim 5, wherein the SS set is based on a common search space set (CSS set) or a UE-specific search space set (USS set).

7. 7. The method of claim 6, wherein the SS set is associated with one or more CORESETs based on the first CORESET pool index or the second CORESET pool index.

8. The timing advance command indicates an index related to a timing adjustment; N for calculating a Timing Advance (TA) based on an index related to the timing adjustment ＴＡ 2. The method of claim 1, wherein:

9. The TA is associated with a first Timing Advance Group (TAG) or a second Timing Advance Group (TAG); the first TAG is associated with the first CORESET pool index; 9. The method of claim 8, wherein the second TAG is associated with the second CORESET pool index.

10. 10. The method of claim 9, wherein a Time Alignment Timer associated with the TA is a first Time Alignment Timer associated with the first TAG or a second Time Alignment Timer associated with the second TAG.

11. the first Time Alignment Timer and / or the second Time Alignment Timer are associated with a Primary Timing Advance Group (PTAG), and based on the first Time Alignment Timer and the second Time Alignment Timer expiring, 11. The method of claim 10, wherein a configuration for uplink transmission is released.

12. Upon expiration of a Time Alignment Timer associated with the TA, A random access preamble is transmitted based on an SSB index associated with the expired Time Alignment Timer; The method of claim 10 , wherein an SSB index associated with the expired Time Alignment Timer is associated with the first CORESET pool index or the second CORESET pool index.

13. The SSB index is based on one or more SSB indices, Based on the one or more SSB indexes including i) a first SSB index associated with the first CORESET pool index, and ii) a second SSB index associated with the second CORESET pool index, A first random access preamble is transmitted based on the first SSB index; 2. The method of claim 1, wherein a second random access preamble is transmitted based on the second SSB index.

14. In a terminal operating in a wireless communication system, one or more transceivers; one or more processors; and one or more memories operatively connected to the one or more processors and storing instructions that configure the one or more processors to perform operations based on being executed by the one or more processors; The operation includes: receiving configuration information related to a plurality of control resource sets (CORESETs) from a base station; configuring a CORESET based on a first control resource set pool index (CORESET pool index) and a second control resource set pool index (CORESET pool index) based on the configuration information; receiving downlink control information (DCI) from the base station, the DCI including information on a physical downlink control channel (PDCCH) order, and initiating a random access procedure according to the PDCCH order; transmitting a random access preamble to the base station; and receiving a Random Access Response (RAR) from the base station, The information related to the PDCCH order includes a synchronization signal / physical broadcast channel block index (SSB index), The random access preamble is transmitted based on the SSB index; The random access response (RAR) includes a timing advance command (Timing Advance Command), A terminal, wherein the SSB index is associated with the first CORESET pool index or the second CORESET pool index.

15. 1. An apparatus comprising one or more memories and one or more processors operatively coupled to the one or more memories, comprising: the one or more memories include instructions that, when executed by the one or more processors, configure the one or more processors to perform operations; The operation includes: receiving configuration information related to a plurality of control resource sets (CORESETs) from a base station; configuring a CORESET based on a first control resource set pool index (CORESET pool index) and a second control resource set pool index (CORESET pool index) based on the configuration information; receiving downlink control information (DCI) from the base station, the DCI including information on a physical downlink control channel (PDCCH) order, and initiating a random access procedure according to the PDCCH order; transmitting a random access preamble to the base station; and receiving a Random Access Response (RAR) from the base station, The information related to the PDCCH order includes a synchronization signal / physical broadcast channel block index (SSB index), The random access preamble is transmitted based on the SSB index; The random access response (RAR) includes a timing advance command (Timing Advance Command), The apparatus, wherein the SSB index is related to the first CORESET pool index or the second CORESET pool index.

16. One or more non-transitory computer-readable media storing one or more instructions, one or more instructions executable by one or more processors to configure the one or more processors to perform operations; The operation includes: receiving configuration information related to a plurality of control resource sets (CORESETs) from a base station; configuring a CORESET based on a first control resource set pool index (CORESET pool index) and a second control resource set pool index (CORESET pool index) based on the configuration information; receiving downlink control information (DCI) from the base station, the DCI including information on a physical downlink control channel (PDCCH) order, and initiating a random access procedure according to the PDCCH order; transmitting a random access preamble to the base station; and receiving a Random Access Response (RAR) from the base station, The information related to the PDCCH order includes a synchronization signal / physical broadcast channel block index (SSB index), The random access preamble is transmitted based on the SSB index; The random access response (RAR) includes a timing advance command (Timing Advance Command), One or more non-transitory computer-readable media, wherein the SSB index is related to the first CORESET pool index or the second CORESET pool index.

17. 1. A method performed by a base station in a wireless communication system, comprising: transmitting configuration information related to a plurality of control resource sets (CORESETs) to a terminal; a CORESET based on a first control resource set pool index (CORESET pool index) and a second control resource set pool index (CORESET pool index) is configured based on the configuration information; transmitting downlink control information (DCI) to the terminal, the DCI including information on a physical downlink control channel (PDCCH) order, and initiating a random access procedure according to the PDCCH order; receiving a random access preamble from the terminal; and transmitting a Random Access Response (RAR) to the terminal, The information related to the PDCCH order includes a synchronization signal / physical broadcast channel block index (SSB index), The random access preamble is received based on the SSB index; The random access response (RAR) includes a timing advance command (Timing Advance Command), The method, wherein the SSB index is related to the first CORESET pool index or the second CORESET pool index.

18. 1. A base station operating in a wireless communication system, comprising: one or more transceivers; one or more processors; and one or more memories operatively connected to the one or more processors and storing instructions that configure the one or more processors to perform operations based on being executed by the one or more processors; The operation includes: transmitting configuration information related to a plurality of control resource sets (CORESETs) to a terminal; a CORESET based on a first control resource set pool index (CORESET pool index) and a second control resource set pool index (CORESET pool index) is configured based on the configuration information; transmitting downlink control information (DCI) to the terminal, the DCI including information on a physical downlink control channel (PDCCH) order, and initiating a random access procedure according to the PDCCH order; receiving a random access preamble from the terminal; and transmitting a Random Access Response (RAR) to the terminal, The information related to the PDCCH order includes a synchronization signal / physical broadcast channel block index (SSB index), The random access preamble is received based on the SSB index; The random access response (RAR) includes a timing advance command (Timing Advance Command), A base station, wherein the SSB index is related to the first CORESET pool index or the second CORESET pool index.

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