Method and device for transmitting signal for channel state information feedback in wireless communication system

Abstract

A method of a terminal may comprise the steps of: receiving, from a first cell, configuration information for channel state information (CSI) measurement; generating CSI from a downlink (DL) reference signal (RS) received from a second cell on the basis of the configuration information; receiving a first medium access control (MAC) control element (CE) from the first cell; and transmitting a CSI report including the generated CSI to the second cell on the basis of the first MAC CE.

Description

Signal transmission method and device for channel state information feedback in a wireless communication system

[0001] The present invention relates to communication technology for a wireless communication system, and more specifically, to a method and apparatus for transmitting a signal for channel state information (CSI) feedback.

[0002] Along with the advancement of information and communication technology, various wireless communication technologies are being developed. Representative wireless communication technologies include LTE (long term evolution) and NR (new radio), which are defined in the 3GPP (3rd generation partnership project) standards. LTE can be one of the wireless communication technologies among 4G (4th Generation) wireless communication technologies, and NR can be one of the wireless communication technologies among 5G (5th Generation) wireless communication technologies.

[0003] To handle the surge in wireless data following the commercialization of 4G communication systems (e.g., communication systems supporting LTE), 5G communication systems (e.g., communication systems supporting NR) that use frequency bands higher than those of 4G communication systems (e.g., frequency bands below 6 GHz) are being considered. 5G communication systems can support eMBB (enhanced Mobile BroadBand), URLLC (Ultra-Reliable and Low Latency Communication), and mMTC (massive Machine Type Communication).

[0004] Meanwhile, in 5G and 6G communication systems, lower-layer triggered mobility (LTM) procedures and multi-transmission and reception point (TRP) environments are being considered. Accordingly, various improvements are required in the procedure for a terminal to derive channel state information and report it to a base station.

[0005] The objective of the present invention, which is to solve the above-mentioned problems, is to provide a method and apparatus for transmitting a signal for channel state information (CSI) feedback in a wireless communication system.

[0006] A method of a terminal according to a first embodiment of the present invention for achieving the above objective may include: receiving configuration information for measuring channel state information (CSI) from a first cell; generating CSI from a downlink (DL) reference signal (RS) received from a second cell based on the configuration information; receiving a first MAC (medium access control) CE (control element) from the first cell; and transmitting a CSI report including the generated CSI to the second cell based on the first MAC CE.

[0007] The first cell above is a serving cell, and the second cell above may be a lower-layer triggered mobility (LTM) candidate cell.

[0008] The first cell and the second cell may be operated by the same central unit (CU) of the same base station, operated by different CUs of the same base station, or operated by different CUs of different base stations.

[0009] The above configuration information includes a CSI report configuration and a CSI resource configuration, and the CSI resource configuration may include at least one of a set of at least one channel measurement resource (CMR) or a set of at least one interference measurement resource (IMR).

[0010] The above method further comprises: receiving a second MAC CE from the first cell for adding, updating, or releasing attributes of the at least one CMR set, the CMR resource belonging to the at least one CMR set, or the CMR resource belonging to the at least one CMR set; and adding, updating, or releasing attributes of the at least one CMR set, the CMR resource belonging to the at least one CMR set, or the CMR resource belonging to the at least one CMR set based on the second MAC CE, wherein the addition, updating, or release of the CMR resource belonging to the at least one CMR set or the attributes of the CMR resource belonging to the at least one CMR set may be performed by adding, updating, or releasing a TCI (transmission configuration indicator) status identifier corresponding to the CMR resource belonging to the at least one CMR set or the attributes of the CMR resource belonging to the at least one CMR set.

[0011] The above method further comprises: receiving a second MAC CE from the first cell for adding, updating, or releasing attributes of the at least one IMR set, the CMR resource belonging to the at least one IMR set, or the IMR resource belonging to the at least one IMR set; and adding, updating, or releasing attributes of the at least one IMR set, the IMR resource belonging to the at least one IMR set, or the IMR resource belonging to the at least one IMR set based on the second MAC CE, wherein the addition, updating, or release of the IMR resource belonging to the at least one IMR set or the attributes of the IMR resource belonging to the at least one IMR set may be performed by adding, updating, or releasing a TCI (transmission configuration indicator) status identifier corresponding to the IMR resource belonging to the at least one IMR set or the attributes of the IMR resource belonging to the at least one IMR set.

[0012] The above CSI report can be transmitted to the second cell via a physical uplink shared channel (PUSCH) within a random access (RA) procedure for the second cell.

[0013] The modulation and coding scheme (MCS) applied to the above CSI report is determined based on at least one field among the uplink (UL) grant fields included in the random access response (RA) Msg2 (message 2) received from the first cell within the above RA procedure, and the beta offset for determining the code rate of the above CSI report can be received through radio resource control (RRC) signaling.

[0014] A method of a first base station according to a second embodiment of the present invention for achieving the above objective comprises: a step of transmitting configuration information for measuring channel state information (CSI) through a first cell operated by the first base station to a terminal; and a step of transmitting a first MAC (medium access control) CE (control element) through the first cell to the terminal, wherein the first MAC CE may cause the terminal to transmit a CSI report to the second cell, the report including a CSI derived from a downlink (DL) reference signal (RS) of a second cell operated by the first base station or a second base station different from the first base station.

[0015] The first cell above is a serving cell, and the second cell above may be a lower-layer triggered mobility (LTM) candidate cell.

[0016] The above configuration information includes a CSI report configuration and a CSI resource configuration, and the CSI resource configuration may include at least one of a set of at least one channel measurement resource (CMR) or a set of at least one interference measurement resource (IMR).

[0017] The above method further comprises the step of transmitting a second MAC CE to the terminal through the first cell for adding, changing, or releasing the attributes of the at least one CMR set, the CMR resource belonging to the at least one CMR set, or the CMR resource belonging to the at least one CMR set, and the addition, updating, or release of the CMR resource belonging to the at least one CMR set or the attributes of the CMR resource belonging to the at least one CMR set may be performed by adding, updating, or releasing a TCI (transmission configuration indicator) status identifier corresponding to the CMR resource belonging to the at least one CMR set or the attributes of the CMR resource belonging to the at least one CMR set.

[0018] The above method further comprises the step of transmitting a second MAC CE to the terminal through the first cell for adding, changing, or releasing attributes of the at least one IMR set, the CMR resource belonging to the at least one IMR set, or the IMR resource belonging to the at least one IMR set, and the addition, updating, or release of the IMR resource belonging to the at least one IMR set or the attributes of the IMR resource belonging to the at least one IMR set may be performed by adding, updating, or releasing a TCI (transmission configuration indicator) status identifier corresponding to the IMR resource belonging to the at least one IMR set or the attributes of the IMR resource belonging to the at least one IMR set.

[0019] The above CSI report can be transmitted to the second cell via a physical uplink shared channel (PUSCH) within a random access (RA) procedure for the second cell.

[0020] The modulation and coding scheme (MCS) applied to the above CSI report is determined based on at least one field among the uplink (UL) grant fields included in the random access response (RA) Msg2 (message 2) transmitted from the first cell within the above RA procedure, and the beta offset for determining the code rate of the above CSI report can be transmitted via radio resource control (RRC) signaling.

[0021] A terminal according to a third embodiment of the present invention for achieving the above objective includes at least one processor, and the at least one processor may enable the terminal to perform: receiving configuration information for measuring channel state information (CSI) from a first cell; generating CSI from a downlink (DL) reference signal (RS) received from a second cell based on the configuration information; receiving a first MAC (medium access control) CE (control element) from the first cell; and transmitting a CSI report including the generated CSI to the second cell based on the first MAC CE.

[0022] The first cell above is a serving cell, and the second cell above may be a lower-layer triggered mobility (LTM) candidate cell.

[0023] The above configuration information includes a CSI report configuration and a CSI resource configuration, and the CSI resource configuration may include at least one of a set of at least one channel measurement resource (CMR) or a set of at least one interference measurement resource (IMR).

[0024] The above at least one processor enables the terminal to: receive a second MAC CE from the first cell for adding, updating, or releasing attributes of the at least one CMR set, the CMR resource belonging to the at least one CMR set, or the CMR resource belonging to the at least one CMR set; and further perform the step of adding, updating, or releasing attributes of the at least one CMR set, the CMR resource belonging to the at least one CMR set, or the CMR resource belonging to the at least one CMR set based on the second MAC CE, wherein the addition, updating, or release of the CMR resource belonging to the at least one CMR set or the attributes of the CMR resource belonging to the at least one CMR set may be performed by adding, updating, or releasing a TCI (transmission configuration indicator) status identifier corresponding to the CMR resource belonging to the at least one CMR set or the attributes of the CMR resource belonging to the at least one CMR set.

[0025] The above at least one processor enables the terminal to: receive a second MAC CE from the first cell for adding, updating, or releasing attributes of the at least one IMR set, the CMR resource belonging to the at least one IMR set, or the IMR resource belonging to the at least one IMR set; and further perform the step of adding, updating, or releasing attributes of the at least one IMR set, the IMR resource belonging to the at least one IMR set, or the IMR resource belonging to the at least one IMR set based on the second MAC CE, wherein the addition, updating, or release of the IMR resource belonging to the at least one IMR set or the attributes of the IMR resource belonging to the at least one IMR set may be performed by adding, updating, or releasing a TCI (transmission configuration indicator) status identifier corresponding to the IMR resource belonging to the at least one IMR set or the attributes of the IMR resource belonging to the at least one IMR set.

[0026] According to the embodiments of the present disclosure, various improvements to the CSI reporting procedure can be provided by considering the LTM procedure and multi-TRP environment considered in 5G and 6G communication systems. Accordingly, the embodiments according to the present disclosure can achieve the effects of reducing handover / cell switching delays and signal overhead, increasing reliability, shortening mobility downtime, and improving throughput, boundary quality, and service continuity.

[0027] FIG. 1 is a conceptual diagram illustrating a first embodiment of a communication system.

[0028] FIG. 2 is a block diagram illustrating a first embodiment of a communication node constituting a communication system.

[0029] FIG. 3 is a conceptual diagram illustrating a multi-TRP environment to which embodiments of the present disclosure are applied.

[0030] Figure 4 is a flowchart illustrating the procedure for a terminal to perform a CSI report.

[0031] FIG. 5 is a conceptual diagram illustrating the CSI reporting settings instructed to the terminal and the settings of CSI resources belonging to the CSI reporting settings.

[0032] FIG. 6 is a conceptual diagram illustrating the format of the CSC MAC CE applied to the embodiments of the present disclosure.

[0033] FIGS. 7 to 12 are conceptual diagrams for explaining UEI CSI reporting operations according to embodiments of the present disclosure.

[0034] The present disclosure is capable of various modifications and may have various embodiments, and specific embodiments are illustrated in the drawings and described in detail. However, this is not intended to limit the present disclosure to specific embodiments, and it should be understood that it includes all modifications, equivalents, and substitutions that fall within the spirit and scope of the present disclosure.

[0035] Terms such as "first," "second," etc., may be used to describe various components, but said components should not be limited by said terms. Such terms are used solely for the purpose of distinguishing one component from another. For example, without departing from the scope of the present disclosure, the first component may be named the second component, and similarly, the second component may be named the first component. The term "and / or" includes a combination of a plurality of related described items or any of a plurality of related described items.

[0036] In embodiments of the present disclosure, "at least one of A and B" may mean "at least one of A or B" or "at least one of one or more combinations of A and B". Additionally, in embodiments of the present disclosure, "at least one of A and B" may mean "at least one of A or B" or "at least one of one or more combinations of A and B".

[0037] When it is stated that one component is "connected" or "connected" to another component, it should be understood that while it may be directly connected or connected to that other component, there may also be other components in between. On the other hand, when it is stated that one component is "directly connected" or "directly connected" to another component, it should be understood that there are no other components in between.

[0038] The terms used in this disclosure are used merely to describe specific embodiments and are not intended to limit this disclosure. The singular expression includes the plural expression unless the context clearly indicates otherwise. In this disclosure, terms such as “comprising” or “having” are intended to specify the existence of the features, numbers, steps, actions, components, parts, or combinations thereof described in the specification, and should be understood as not precluding the existence or addition of one or more other features, numbers, steps, actions, components, parts, or combinations thereof.

[0039] Unless otherwise defined, all terms used herein, including technical or scientific terms, have the same meaning as generally understood by those skilled in the art to which this disclosure pertains. Terms such as those defined in commonly used dictionaries should be interpreted as having a meaning consistent with their meaning in the context of the relevant technology, and should not be interpreted in an ideal or overly formal sense unless explicitly defined in this disclosure.

[0040] Hereinafter, preferred embodiments of the present disclosure will be described in more detail with reference to the attached drawings. In order to facilitate an overall understanding of the present disclosure, the same reference numerals are used for identical components in the drawings, and redundant descriptions of identical components are omitted.

[0041] A communication system to which embodiments according to the present disclosure are applied will be described. The communication system to which embodiments according to the present disclosure are applied is not limited to the details described below, and embodiments according to the present disclosure may be applied to various communication systems. Here, the term "communication system" may be used interchangeably with "communication network."

[0042] In the embodiments, "setting an operation (e.g., a transmission operation)" may mean that "setting information for the operation (e.g., an information element, a parameter)" and / or "information directing the execution of the operation" is signaled. "Setting an information element (e.g., a parameter)" may mean that the information element is signaled. The signaling may be at least one of SI (system information) signaling (e.g., transmission of a SIB (system information block) and / or MIB (master information block)), RRC signaling (e.g., transmission of an RRC message, RRC parameter, and / or upper-layer parameter), MAC CE (control element) signaling (e.g., transmission of a MAC message and / or MAC CE and / or MAC subPDU), or PHY signaling (e.g., transmission of DCI (downlink control information), UCI (uplink control information), and / or SCI (sidelink control information).

[0043] FIG. 1 is a conceptual diagram illustrating a first embodiment of a communication system.

[0044] Referring to FIG. 1, the communication system (100) may include a plurality of communication nodes (110-1, 110-2, 110-3, 120-1, 120-2, 130-1, 130-2, 130-3, 130-4, 130-5, 130-6). Additionally, the communication system (100) may further include a core network (e.g., an S-GW (serving-gateway), a P-GW (PDN (packet data network)-gateway), and an MME (mobility management entity)). If the communication system (100) is a 5G communication system (e.g., a new radio (NR) system), the core network may include an AMF (access and mobility management function), a UPF (user plane function), an SMF (session management function), etc.

[0045] Multiple communication nodes (110 to 130) can support communication protocols defined in 3GPP (3rd generation partnership project) standards (e.g., LTE communication protocol, LTE-A communication protocol, NR communication protocol, etc.). Multiple communication nodes (110 to 130) can support CDMA (code division multiple access) technology, WCDMA (wideband CDMA) technology, TDMA (time division multiple access) technology, FDMA (frequency division multiple access) technology, OFDM (orthogonal frequency division multiplexing) technology, Filtered OFDM technology, CP (cyclic prefix)-OFDM technology, DFT-s-OFDM (discrete Fourier transform-spread-OFDM) technology, OFDMA (orthogonal frequency division multiple access) technology, SC (single carrier)-FDMA technology, NOMA (non-orthogonal multiple access) technology, GFDM (generalized frequency division multiplexing) technology, FBMC (filter bank multi-carrier) technology, UFMC (universal filtered multi-carrier) technology, SDMA (space division multiple access) technology, etc. Each of the multiple communication nodes may have the following structure.

[0046] FIG. 2 is a block diagram illustrating a first embodiment of a communication node constituting a communication system.

[0047] Referring to FIG. 2, the communication node (200) may include at least one processor (210), a memory (220), and a transceiver (230) that is connected to a network to perform communication. Additionally, the communication node (200) may further include an input interface device (240), an output interface device (250), a storage device (260), etc. Each component included in the communication node (200) may be connected by a bus (270) to communicate with one another.

[0048] However, each component included in the communication node (200) may be connected via individual interfaces or individual buses centered around the processor (210), rather than via a common bus (270). For example, the processor (210) may be connected via a dedicated interface to at least one of a memory (220), a transmission / reception device (230), an input interface device (240), an output interface device (250), and a storage device (260).

[0049] The processor (210) can execute a program command stored in at least one of the memory (220) and the storage device (260). The processor (210) may mean a central processing unit (CPU), a graphics processing unit (GPU), or a dedicated processor on which the methods according to embodiments of the present disclosure are performed. Each of the memory (220) and the storage device (260) may be composed of at least one of a volatile storage medium and a non-volatile storage medium. For example, the memory (220) may be composed of at least one of read-only memory (ROM) and random access memory (RAM).

[0050] Referring again to FIG. 1, the communication system (100) may include a plurality of base stations (110-1, 110-2, 110-3, 120-1, 120-2) and a plurality of terminals (130-1, 130-2, 130-3, 130-4, 130-5, 130-6). Each of the first base station (110-1), the second base station (110-2), and the third base station (110-3) may form a macro cell. Each of the fourth base station (120-1) and the fifth base station (120-2) may form a small cell. The fourth base station (120-1), the third terminal (130-3), and the fourth terminal (130-4) may be located within the cell coverage of the first base station (110-1). The second terminal (130-2), the fourth terminal (130-4), and the fifth terminal (130-5) may be located within the cell coverage of the second base station (110-2). The fifth base station (120-2), the fourth terminal (130-4), the fifth terminal (130-5), and the sixth terminal (130-6) may be located within the cell coverage of the third base station (110-3). The first terminal (130-1) may be located within the cell coverage of the fourth base station (120-1). The sixth terminal (130-6) may be located within the cell coverage of the fifth base station (120-2).

[0051] Here, each of the multiple base stations (110-1, 110-2, 110-3, 120-1, 120-2) may be referred to as NB (NodeB), eNB (evolved NodeB), gNB, ABS (advanced base station), HR-BS (high reliability-base station), BTS (base transceiver station), radio base station, radio transceiver, access point, access node, RAS (radio access station), MMR-BS (mobile multihop relay-base station), RS (relay station), ARS (advanced relay station), HR-RS (high reliability-relay station), HNB (home NodeB), HeNB (home eNodeB), RSU (road side unit), RRH (radio remote head), TP (transmission point), TRP (transmission and reception point), etc.

[0052] Each of the multiple terminals (130-1, 130-2, 130-3, 130-4, 130-5, 130-6) may be referred to as UE (user equipment), TE (terminal equipment), AMS (advanced mobile station), HR-MS (high reliability-mobile station), terminal, access terminal, mobile terminal, station, subscriber station, mobile station, portable subscriber station, node, device, OBU (on board unit), etc.

[0053] Meanwhile, each of the multiple base stations (110-1, 110-2, 110-3, 120-1, 120-2) may operate in different frequency bands or in the same frequency band. Each of the multiple base stations (110-1, 110-2, 110-3, 120-1, 120-2) may be connected to each other via an ideal backhaul link or a non-ideal backhaul link, and may exchange information with each other via an ideal backhaul link or a non-ideal backhaul link. Each of the multiple base stations (110-1, 110-2, 110-3, 120-1, 120-2) may be connected to a core network via an ideal backhaul link or a non-ideal backhaul link. Each of the multiple base stations (110-1, 110-2, 110-3, 120-1, 120-2) can transmit a signal received from the core network to the corresponding terminal (130-1, 130-2, 130-3, 130-4, 130-5, 130-6), and can transmit a signal received from the corresponding terminal (130-1, 130-2, 130-3, 130-4, 130-5, 130-6) to the core network.

[0054] In addition, each of the multiple base stations (110-1, 110-2, 110-3, 120-1, 120-2) can support MIMO (multi-input multi-output) transmission (e.g., SU (single user)-MIMO, MU (multi user)-MIMO, massive MIMO, etc.), CoMP (coordinated multipoint) transmission, carrier aggregation (CA) transmission, transmission in an unlicensed band, device-to-device communication (D2D) (or ProSe (proximity services)), IoT (Internet of Things) communication, dual connectivity (DC), etc. Here, each of the plurality of terminals (130-1, 130-2, 130-3, 130-4, 130-5, 130-6) can perform an operation corresponding to the base station (110-1, 110-2, 110-3, 120-1, 120-2) and an operation supported by the base station (110-1, 110-2, 110-3, 120-1, 120-2). For example, the second base station (110-2) can transmit a signal to the fourth terminal (130-4) based on the SU-MIMO method, and the fourth terminal (130-4) can receive a signal from the second base station (110-2) based on the SU-MIMO method. Alternatively, the second base station (110-2) can transmit a signal to the fourth terminal (130-4) and the fifth terminal (130-5) based on the MU-MIMO method, and each of the fourth terminal (130-4) and the fifth terminal (130-5) can receive a signal from the second base station (110-2) by the MU-MIMO method.

[0055] Each of the first base station (110-1), the second base station (110-2), and the third base station (110-3) can transmit a signal to the fourth terminal (130-4) based on the CoMP method, and the fourth terminal (130-4) can receive a signal from the first base station (110-1), the second base station (110-2), and the third base station (110-3) by the CoMP method. Each of the multiple base stations (110-1, 110-2, 110-3, 120-1, 120-2) can transmit and receive signals based on the CA method with terminals (130-1, 130-2, 130-3, 130-4, 130-5, 130-6) within its cell coverage area. Each of the first base station (110-1), the second base station (110-2), and the third base station (110-3) can control D2D between the fourth terminal (130-4) and the fifth terminal (130-5), and each of the fourth terminal (130-4) and the fifth terminal (130-5) can perform D2D by controlling each of the second base station (110-2) and the third base station (110-3).

[0056] Next, methods of operation of communication nodes in a communication system will be described. Even when a method performed by a first communication node among the communication nodes (e.g., transmission or reception of a signal) is described, the corresponding second communication node may perform a method corresponding to the method performed by the first communication node (e.g., reception or transmission of a signal). In other words, when the operation of a terminal is described, the corresponding base station may perform an operation corresponding to the operation of the terminal. Conversely, when the operation of a base station is described, the corresponding terminal may perform an operation corresponding to the operation of the base station.

[0057]

[0058] To reduce the data error rate, a low modulation and coding scheme (MCS) level (e.g., a low MCS index) may be applied. To prevent an increase in the size of the field indicated by downlink control information (DCI), the most frequently used MCS(s) may be selected. Subsequently, to apply a low MCS, repetitive transmission operations may be supported. Since the modulation rate of quadrature phase shift keying (QPSK) is the lowest, the effect of further lowering the coding rate may occur. In particular, since transmission power is limited in uplink transmission, repetitive transmission operations may be performed in the time domain rather than the frequency domain.

[0059] eMBB (enhanced Mobile BroadBand) traffic and URLLC (Ultra-Reliable and Low Latency Communication) traffic may use a low MCS for different purposes. eMBB traffic may use a low MCS to extend reach. On the other hand, URLLC traffic may use a low MCS to reduce latency and achieve a low error rate. Because the required conditions differ, eMBB traffic may be retransmitted even if latency occurs, whereas URLLC traffic may be transmitted using a new MCS (e.g., a low MCS) rather than retransmission. The new MCS can be set by RRC messages and / or DCI.

[0060] To support repeated transmissions for eMBB traffic in the time domain, PUSCH (physical uplink shared channel) repetition (e.g., PUSCH repetition type A) may be introduced. In this case, PUSCH allocated on a slot basis may be repeated. To extend reach, time resources may be allocated to multiple slots. When PUSCH repetition type A is used, time resources may be configured by RRC messages and / or DCIs. The number of PUSCH repetitions may be indicated by RRC messages, and the time resource in which PUSCH is transmitted in the first slot may be indicated by DCIs (e.g., Type 2 CG (configured grant) or dynamic grants) or RRC messages (e.g., Type 1 CGs).

[0061] Since latency occurs when URLLC traffic is repeatedly transmitted, it may not be appropriate to repeatedly transmit URLLC traffic. However, if a sufficiently low MCS is used, the latency for decoding URLLC traffic can be reduced. That is, when a sufficiently low MCS is used, the number of resource elements (REs) mapped to URLLC traffic can increase, and the base station (e.g., the base station decoder) must wait until all REs are received. In this case, the latency for decoding URLLC traffic can be reduced.

[0062] On the other hand, when a PUSCH with a somewhat high MCS is repeatedly transmitted, the base station can perform decoding operations using only a portion of the REs. Therefore, the time of the first successful decoding in a repeated PUSCH transmission (e.g., a repeated PUSCH transmission with a somewhat high MCS) may be earlier than the time of the first successful decoding in a PUSCH transmission without repetition (e.g., a repeated PUSCH transmission with a low MCS). Unnecessary delays may occur when PUSCH repeat type A is used, and PUSCH repeat type B may be introduced to reduce the delay time for repeated transmissions. When PUSCH repeat type B is used, PUSCHs allocated in mini-slot units may be repeatedly transmitted. When PUSCH repeat type B is used, time resources may be set by RRC messages and / or DCIs. The combination of reference time resources and the number of repeated transmissions of a PUSCH instance may be indicated by a DCI (e.g., Type 2 CG and / or dynamic grant) or an RRC message (e.g., Type 1 CG).

[0063] To control the transmission power of an SRS resource indicated by an SRI (sounding reference signal resource indicator), the base station may estimate path attenuation for each SRS resource. The base station may use a DCI to control the transmission power for the SRS resource(s). The transmission power of the SRS resource(s) may be controlled based on the estimated path attenuation. The DCI may be a scheduling DCI (e.g., DCI format 0_0, DCI format 0_1, DCI format 0_2, DCI format 1_0, DCI format 1_1, or DCI format 1_2) or a GC (group common)-DCI (e.g., DCI format 2_2 or DCI format 2_3). The DCI may include a field indicating a transmit power control (TPC) command, and the TPC command may be used to control the transmission power of the terminal. For example, the transmission power of the terminal may be increased or decreased based on TPC commands included in the DCI. To determine the transmission power of PUSCH, the terminal may consider a value obtained based on path attenuation, a value according to TPC commands included in the DCI, and / or the PUSCH bandwidth indicated by the DCI.

[0064] The base station may configure two or more sets to the terminal using upper-layer signaling. The terminal may receive configuration information for two or more sets from the base station. The elements constituting each of the two or more sets may be transmission power parameter(s) and may be instructed to be suitable for different scenarios (e.g., URLLC scenario, eMBB scenario). The terminal may receive a scheduling DCI or an activating DCI from the base station that allocates PUSCH resources, and the scheduling DCI or activating DCI may instruct a set that interprets the transmission power parameter(s). If the sets of transmission power parameter(s) are different, the magnitude of the increase or decrease in transmission power instructed by the same TPC command may differ.

[0065] When a Type 1 CG or a Type 2 CG is used, the transmission power can be determined based on DCI format 2_3 for the SRI associated with the PUSCH instance. When a Type 2 CG is used, the enabled DCI may indicate a set of transmission power parameter(s) applied to the PUSCH occasion. A PUSCH occasion may refer to a PUSCH instance. The terminal may obtain a TPC command for the SRI by receiving a GC (group common)-DCI, interpret the TPC command to fit the set of transmission power parameter(s) indicated by the base station, and derive the transmission power applied to the PUSCH instance based on the interpretation result.

[0066] In a dynamically scheduled PUSCH transmission, the terminal can derive the transmission power applied to the PUSCH instance based on a combination of the GC-DCI and the scheduling DCI. By receiving the GC-DCI, the terminal can identify the TPC command of the SRI and store the identified TPC command. In a dynamically scheduled PUSCH transmission, the set of transmission power parameter(s) and / or TPC command applied to the PUSCH occupancy may be indicated by the scheduling DCI. The terminal can derive the transmission power applied to the PUSCH instance based on the transmission power of the SRI associated with the PUSCH instance.

[0067] HARQ-ACK repeated transmissions may be directed (or configured) by upper-layer signaling for each PUCCH (physical uplink control channel) format. The number of repeated transmissions for PUCCH format i may be set independently. i may be 1, 3, or 4. The terminal may repeatedly transmit the PUCCH format in slots. In this case, the PUCCH format may be transmitted using the same time resource in each slot.

[0068] UCI (uplink control information) types can be classified according to the type of information included in the UCI. A UCI may include at least one of SR (scheduling request), L1-RSRP (reference signal received power), HARQ-ACK, or CSI (channel state information). In the embodiments, UCI and UCI type may be used interchangeably. In the repetitive transmission operation of a UCI, only one UCI type may be transmitted. To support this operation, the priority of UCI types may be defined in the technical specifications. One UCI type may be selected, and a PUCCH containing one UCI type may be repetitively transmitted. In this case, the terminal may assume that no other UCI type is transmitted before the transmission of the corresponding UCI type is completed. To support this operation, the base station may instruct the terminal to transmit a UCI (e.g., SR or HARQ-ACK) after the PUCCH transmission is completed. The waiting time for the transmission of the corresponding UCI may be long, and such waiting time may act as a constraint on scheduling for the base station.

[0069] "Where it is indicated that HARQ-ACKs be transmitted in the same slot (or the same sub-slot)" or "where PUCCH time resources indicated by DCI and / or RRC messages allocating a PDSCH (physical downlink shared channel) overlap," the terminal may generate a HARQ codebook to be transmitted in a single PUCCH (e.g., a single PUCCH time resource). Within the HARQ codebook, HARQ-ACK bits may be arranged according to the order defined in the technical specification. Information bits may be generated by the above-described operation. The terminal may generate coded bits by performing an encoding operation.

[0070] In the encoding operation, Reed-Muller codes or polar codes may be used. The code rate applied in the encoding operation may be indicated by upper-layer signaling. For example, in the PUCCH format, one value may be the code rate and may be indicated to the terminal.

[0071] A single codeword can be mapped to a single PUCCH. In a PUCCH repeated transmission operation, a single UCI type can be generated as a codeword. When a PUCCH is transmitted once, information bits of one UCI type or two or more UCI types can be concatenated, and the terminal can generate a single codeword by performing the same encoding operation on the information bits. When Reed-Muller codes or polar codes are used, performing a soft combining operation may be difficult in terms of implementation. Therefore, even when a PUCCH is transmitted repeatedly, the same codeword can be transmitted, and the base station can perform a chase combining operation on the same codeword. An encoded bit or codeword may refer to a bit sequence in which multiple code blocks are concatenated. A modulation operation can be performed on the codeword, and the result of the modulation operation can be mapped to an RE.

[0072] Meanwhile, the same UCI type can be considered as different information. The same UCI type considered as different information can be mapped. For example, UCIs can be created to support traffic with different priorities. A UCI supporting eMBB traffic (e.g., SR or HARQ-ACK) can be considered as information distinct from a UCI supporting URLLC traffic (e.g., SR or HARQ-ACK). In this case, even if the UCI types are the same, they can be distinguished as different information.

[0073] The encoded UCI can be mapped to a PUCCH. The same preprocessing method (e.g., spatial information, spatial relation) may be maintained during the PUCCH transmission operation. Alternatively, during the PUCCH transmission operation, the use of different preprocessing methods for each PUCCH may be permitted by the base station's RRC signaling.

[0074] To support URLLC traffic, it may be desirable for the terminal to perform frequent receive operations on DL (downlink) resources and / or frequent transmit operations on UL (uplink) resources. In a TDD (time division duplex) system, the terminal can operate based on a half-duplex method. Therefore, the support time for DL ​​traffic and / or UL traffic may increase depending on the slot pattern. On the other hand, in a FDD (frequency division duplex) system, the terminal can utilize DL resources and UL resources. Therefore, the aforementioned problems in a TDD system may not occur in an FDD system. An FDD system can use two or more carriers. In a TDD system, if two or more serving cells are configured on the terminal, the terminal can utilize DL resources and UL resources.

[0075] In a communication system comprising at least one carrier to which FDD is applied (hereinafter referred to as the "FDD carrier"), there may be no problem regarding the latency of the terminal. In a communication system comprising only carrier(s) to which TDD is applied (hereinafter referred to as "TDD carrier(s")), a problem regarding the latency of the terminal may exist. To solve the above-mentioned problem, slots in the TDD carriers may be configured according to different patterns.

[0076] Carrier aggregation (CA) can be configured on the terminal, and PCell and SCell(s) can be enabled. Depending on whether a common search space (CSS) set is included, a cell can be classified as a PCell or a SCell. For example, a PCell may include a CSS set, and a SCell may not include a CSS set. To reduce latency in communication systems supporting URLLC traffic, slots having different patterns can be configured and / or instructed on the terminal.

[0077] eMBB traffic or URLLC traffic may be supported in licensed bands, but it may also be supported in unlicensed bands. Carrier(s) in licensed bands or carrier(s) in unlicensed bands may be utilized exclusively, but depending on the base station configuration, both carrier(s) in licensed bands and carrier(s) in unlicensed bands may be utilized through frequency aggregation.

[0078] In the embodiments, two or more terminals may receive data from one or more TRPs and transmit data to one or more TRPs. It may be assumed that one base station or one server performs management operations and / or scheduling operations for one or more TRPs among the plurality of TRPs. TRPs may be directly connected to each other. Alternatively, TRPs may be connected through a base station. The above-described connection may be a connection according to an Xn interface or a wireless interface (e.g., an interface of 3GPP NR).

[0079] Shadow zones may occur between the areas supported by TRPs. Therefore, TRPs can resolve these shadow zones through cooperative transmission. Cooperative transmission can be performed for terminals located between TRPs. Even when shadow zones do not occur, the quality of the wireless link can be improved by installing many TRPs (or base stations) to transmit and receive large amounts of data.

[0080] Depending on the cooperative transmission and reception of TRPs, communication methods can be classified into dynamic point selection (DPS) and joint transmission (JT). For a specific set of physical resource blocks (PRBs), DPS may be a method of receiving data through a single TRP, while JT may be a method of receiving data through two or more TRPs. Dynamic point blanking (DPB) may be a type of JT. When DPB is used, the terminal may not receive data from some TRPs and may receive data from the remaining TRPs. JT can be classified into coherent JP and noncoherent JP. Coherent JP or noncoherent JP may be used depending on whether a coherent combining operation is performed on the signals received from the TRPs.

[0081] Depending on the latency and traffic tolerance of the backhaul network to which the base stations or TRPs are connected, TRPs may or may not participate in real-time cooperative transmission and reception. A terminal may support JT through a single DCI (i.e., single DCI (sDCI)). Alternatively, a terminal may support JT through multiple DCIs (i.e., multi-DCI (mDCI)).

[0082] When using sDCI, the terminal can transmit and receive data with TRPs. When using sDCI, it is desirable for TRPs to be able to cooperate through the backhaul network without latency. When using mDCI, the terminal can transmit and receive data with some TRPs. When the terminal transmits and receives data with other TRPs, it is desirable to allocate semi-fixed resources to these TRPs because it is difficult for them to cooperate in real time through the backhaul network.

[0083] In conventional technical specifications, a CORESET pool index was introduced to identify TRPs. A CORESET pool is a collection of CORESETs, and the TCI (transmission configuration indication) state applicable to each CORESET can be independently indicated to the terminal via RRC signaling and / or MAC control elements (CEs). Therefore, a CORESET pool index does not necessarily correspond to a TRP; more specifically, if TRPs are distinguished into TxPs (transmission points) and RxPs (reception points), the CORESET pool index can correspond to an RxP. For example, an Rx beam received from a TxP is derived from a TCI state, and uplink signals / channels scheduled from DCIs discovered in CORESETs belonging to the CORESET pool indicated by a single CORESET pool index can be interpreted as being received at the same RxP.

[0084] For a terminal to gain benefits from coherent combining, the TRPs for that terminal must be synchronized to some extent, and CSI reports for the TRPs must also be shared. If this is not the case, performing noncoherent combining at the terminal is advantageous in terms of performance.

[0085] If the terminal is mounted in a vehicle, constraints on its size and weight may be relaxed. However, in the case of a terminal carried directly by a person, portability may also be a consideration.

[0086] Small cells or IAB nodes may be deployed to extend the signal reach. The transmission capacity of small cells or IAB nodes can be affected by the quality of the backhaul link, and securing a backhaul network can be costly. As an alternative, wireless relay devices can be deployed to deliver higher-quality signals to terminals. Wireless relay devices can be classified into various types depending on the method of signal transmission. The more functions a wireless relay device supports, the more performance it can demonstrate similar to a base station, while the fewer functions it supports, the lower the cost of deployment. The wireless relay device considered in this invention allows for beam formation for terminals while performing the minimum function of transmitting data. The base station must transmit wireless signals to control such a wireless relay device. Appropriate parameters for the wireless relay device can be set by these wireless signals.

[0087] In the present disclosure, transmission of a channel may mean transmission of a message, data, signal, and / or information through said channel, and reception of a channel may mean transmission of a message, data, signal, and / or information through said channel. The channel may be a PDCCH (physical downlink control channel), PDSCH (physical downlink shared channel), PUCCH (physical uplink control channel), PUSCH (physical uplink shared channel), PRACH (physical random access channel), PSBCH (physical sidelink broadcast channel), PSCCH (physical sidelink control channel), PSSCH (physical sidelink shared channel), and / or PSFCH (physical sidelink feedback channel).

[0088] In a communication system that supports TDD (time division duplex), DL (downlink) communication and UL (uplink) communication can be performed in different time resources. The ratio between the DL time during which DL communication is performed and the UL time during which UL communication is performed can be determined by the ratio of traffic (e.g., DL traffic and / or UL traffic). For example, in an NR system, since the amount of DL traffic is greater than the amount of UL traffic, DL slots may be allocated more than UL slots. For example, slots (e.g., slot patterns) may be configured to repeat the DDDSU pattern. D may represent a DL slot, S may represent a slot containing DL symbol(s), FL (flexible) symbol(s), and UL symbol(s), and U may represent a UL slot. The arrangement order of symbols in the S slot may be DL symbol(s) - FL symbol(s) - DL symbol(s). A base station may indicate or set a slot pattern to terminal(s) through signaling (e.g., RRC signaling). The base station may indicate some of the FL symbols set by RRC signaling as DL symbols(s) or UL symbols(s). Some of the FL symbols(s) may be indicated as DL symbols(s) or UL symbols(s) by DCI.

[0089] A terminal located in the boundary area of ​​a cell may repeatedly transmit UL signals / channels to deliver UL traffic to a base station. In this case, at the base station, the signal-to-interference plus noise ratio (SINR) may be improved and the block error rate (BLER) may be reduced. In the present disclosure, UL signals / channels may mean UL signals and / or UL channels, and DL signals / channels may mean DL signals and / or DL ​​channels. A base station may instruct a terminal to repeatedly transmit UL signals / channels, and the terminal may repeatedly transmit UL signals / channels based on the instructions of the base station. A base station may instruct a terminal to repeatedly transmit DL signals / channels, and the terminal may repeatedly receive DL signals / channels based on the instructions of the base station. If UL slots do not occur frequently, a significant delay may occur for the terminal to acquire sufficient UL slots for repeated transmission. For example, "when the DDDSU pattern is set and the SCS (subcarrier spacing) is 30 kHz," the UL slot may occur every 2.5 ms. In this case, the time required for four repeated transmissions of the UL signal / channel may be 10 ms.

[0090]

[0091] LTM (low-layer triggered mobility) framework

[0092] FIG. 3 is a conceptual diagram illustrating a multi-TRP environment to which embodiments of the present disclosure are applied.

[0093] Referring to FIG. 3, an environment in which a terminal and several TRPs (or cells) are deployed is illustrated. When the terminal establishes an RRC connection with a base station, there may be a serving TRP, and other TRPs may be candidate TRPs. The terminal receives downlink (DL) reference signals (RS) from the candidate TRPs and can perform radio resource measurement (RRM) or channel state information (CSI) measurements. For convenience of explanation, one of the candidate TRPs may be referred to as the target TRP.

[0094] In the following description, "cell" and "TRP" can be understood as corresponding concepts. That is, a serving TRP can be referred to as a serving cell, and a candidate TRP can be referred to as a candidate cell. Similarly, a serving cell can be referred to as a serving TRP, and a candidate cell can be referred to as a candidate TRP. Alternatively, depending on the context, a base station, a cell, and a TRP can be understood as corresponding concepts. That is, a serving base station can be referred to as a serving cell or a serving TRP, a candidate base station can be referred to as a candidate cell or a candidate TRP, and a target base station can be referred to as a target cell or a target TRP.

[0095] Figure 4 is a flowchart illustrating the procedure for a terminal to perform a CSI report.

[0096] Referring to FIG. 4, the terminal can generally perform CSI reporting to the serving TRP. The terminal can receive DL-RS from the serving TRP and / or candidate TRP(s) (or target TRP) (S410) and transmit the measurement results for the DL-RS to the serving TRP as a CSI report (S420). Meanwhile, prior to step (S410), the terminal can perform a step (not shown) of receiving configuration information for CSI measurement from the serving TRP. The configuration information may include resource information for receiving DL-RS transmitted from the serving TRP and DL-RS transmitted from the candidate TRP(s) (or target TRP), and information regarding the sequences of the DL-RS. That is, the configuration information may include report configuration information and resource configuration information to be described later.

[0097] The CSI report may be a beam report for beam management or a report including conventional CSI such as PMI / RI / CQI. The terminal's CSI reporting operation may follow instructions from the serving TRP. Figure 4 illustrates a procedure in which the terminal transmits a CSI report based on DL RSs received from the serving TRP and / or candidate TRPs, but the terminal may transmit SRSs to the serving TRP and / or candidate TRPs, and the serving TRP and / or candidate TRPs may measure the SRSs.

[0098] The serving TRP can transmit information about the terminal (e.g., RRC context and / or user plane context) to the target TRP via backhaul (S430).

[0099] The serving TRP can transmit upper layer signaling (e.g., MAC CE or RRC signaling) to the terminal to enable the terminal to perform cell switching (S440).

[0100] CSI report(s) may be transmitted via PUSCH or PUCCH. A single PUSCH or PUCCH may contain two or more CSI report(s). In this case, the report ID of each CSI report may be managed. The type of CSI (report quantity) included in the CSI report corresponding to each CSI report ID may be indicated to the terminal via upper-layer signaling. For example, the types of CSI may include L1-RSRP, CQI, PMI, and RI.

[0101] Meanwhile, the terminal can obtain DL synchronization with the candidate TRP using the SSB received from the candidate TRP. Here, DL synchronization refers to time synchronization and frequency synchronization. Time synchronization may refer to sampling timing recovery, etc. Securing time synchronization does not necessarily mean deriving the slot offset between the serving TRP and the candidate TRP. Frequency synchronization may refer to carrier phase recovery, etc.

[0102] In the method proposed in the present disclosure, the terminal can perform early beam management by receiving CSI-RS from a candidate TRP. The terminal can receive CSI-RS from a candidate TRP for which DL synchronization has been acquired. In one example, the terminal can perform beam management for the candidate TRP using the received CSI-RS. In one example, the terminal can perform beam management for the candidate TRP or acquire a CSI for the candidate TRP using the received CSI-RS. Here, beam management using CSI-RS and CSI acquisition using CSI-RS may use CSI-RS resources belonging to different CSI-RS resource sets. The serving TRP can direct the terminal to the corresponding CSI-RS resource set(s) and CSI-RS resource(s).

[0103] A terminal that receives a dynamic instruction to schedule a PUSCH may send a CSI report to a serving TRP using the PUSCH. To do this, the serving TRP may assume that the terminal is in an RRC connected state, or that the terminal has not entered discontinuous reception (DRX) mode.

[0104] If a terminal can send a PUSCH to a serving TRP even when in an RRC inactive state, the PUSCH may include a CSI report. In one example, the terminal may send a PUSCH from a pre-scheduled resource to transmit a small amount of data (e.g., small data transmission, SDT).

[0105] Meanwhile, the terminal may need to measure the candidate TRP's CSI-RS and transmit a CSI report (i.e., a PUSCH containing the CSI report) including the measured value of the candidate TRP's CSI-RS to the candidate TRP. A restrictive situation (i.e., a situation where a random connection procedure is performed) may be considered for the terminal to transmit a PUSCH to a candidate TRP that has not established an RRC connection state (i.e., a camping cell).

[0106] Generally, a terminal can perform a contention-based random access (i.e., CBRA) procedure with a camping cell, a serving cell, or a candidate cell. That is, the random access procedure may mean a procedure for exchanging Msg1, Msg2, Msg3, and / or Msg4 between the terminal and the cell.

[0107] In the case of a camping cell, since the terminal is in the stage prior to receiving Msg4 from the camping cell, it is not yet determined whether contention for the preamble selected by the terminal (i.e., the PRACH preamble sent to the camping cell) has been resolved. Therefore, if the terminal successfully receives Msg4 from the camping cell, the terminal establishes an RRC connection with the camping cell, and the camping cell can be converted into a serving cell.

[0108] In the case of the serving cell, the serving cell can identify the terminal because the terminal has already been assigned a C-RNTI from the serving cell. Therefore, to clarify the reason why the terminal is performing the random access procedure, the terminal may report to the serving cell, including the RACH cause, in Msg3 or PUSCH.

[0109] The terminal can perform a conditional cell handover or LTM (L1 / L2-triggered mobility). In the previously described step (S430), the serving cell can use backhaul to transmit part or all of the RRC context for the terminal to adjacent cells (i.e., candidate cells). The terminal can perform an RRM measurement or a CSI measurement using the DL RS (SSB or CSI-RS) received from the candidate cells.

[0110] In one example, the RRM measurement may refer to an SS-RSRP or SS-RSRQ measurement. The RRM measurement result is transmitted to the terminal's upper layer after undergoing L3 filtering, and if the RRM measurement result satisfies event conditions, it may be considered that an event has occurred. The terminal may report the RRM measurement result to the serving cell or to the camping cell by transmitting an uplink signal (e.g., a PRACH preamble), and the terminal's operation may vary depending on the event that occurred. Events may be defined in technical specifications. Parameters applicable to each event may be derived from system information from the camping cell.

[0111] In one example, CSI measurement and reporting can be performed based on report configuration and resource configuration directed by upper-level signaling received from serving cells. DL RS received from candidate cells can be utilized for CSI measurement and reporting.

[0112] The terminal can determine whether two or more events (or conditions) occur by measuring DL RS. If an event is detected, the terminal can perform a subsequent operation. Various events may be defined depending on the purpose.

[0113] Some events may be based on physical layer measurements. The terminal can specify conditions using L1-RSRP. Events and subsequent actions may be intended for switching a serving beam or for switching a TRP. To switch to another beam belonging to the same TRP, the terminal may perform measurements on one or more candidate DL RSs. Or, to switch to a beam belonging to a different TRP, the terminal may perform measurements on candidate DL RSs belonging to two or more TRPs. Here, the TRPs may be TRPs belonging to the serving cell. Alternatively, the terminal may switch from a serving TRP to another TRP. The other TRP may be a TRP that does not belong to the serving cell.

[0114]

[0115] The terminal can compare measurements for two or more DL RSs with each other. Alternatively, the terminal can compare a measurement for a single DL RS with a reference value. Events can be further subdivided and classified according to purpose and scenario. For event detection, a current beam and a candidate beam or new beam need to be defined.

[0116] For convenience of explanation, the current beam (or serving beam, serving beam RS, current RS) may refer to a TCI state among the TCI states activated by the serving base station that the terminal has instructed to be used for scheduling. If both qcl-typeA and qcl-typeD are defined in the TCI state, the current beam may be indicated based on the RS associated with qcl-typeD. If only qcl-typeA is defined in the TCI state, the current beam may be indicated based on the RS associated with qcl-typeA.

[0117] A candidate RS (or candidate beam RS) may be received by the terminal from the same TRP as the serving TRP or from a TRP different from the serving TRP. Alternatively, a candidate RS may be received by the terminal from a TRP belonging to the serving cell or from a TRP belonging to a cell that is not the serving cell. Like the current RS, the candidate RS may refer to information that provides the terminal's reception space filter in the TCI state.

[0118] For an event to be detected, it is not sufficient for a single event instance to occur to the terminal; multiple event instances may need to occur continuously. This is because if the terminal performs subsequent procedures based on the occurrence of only a single event instance, events may occur very frequently due to the fading of the wireless channel. This phenomenon can be referred to as the ping-pong effect. Therefore, an event may be considered detected only when a predetermined number of event instances occur over a predetermined period. For the sake of convenience of explanation, an event instance can be expressed as a unit in which the terminal recognizes that a specific event condition has been satisfied. The terminal may determine that a specific event has occurred or been detected if a predetermined number of event instances for that specific event are counted over a predetermined period. Here, the predetermined number may be a value instructed to the terminal by the serving base station through upper-layer signaling.

[0119] In the case of a single event, the terminal can compare the measurement value of the serving beam RS with a threshold value and observe event instances where the measurement value of the serving beam RS becomes smaller than the threshold value. If, during a predetermined period, the number of event instances where the measurement value of the serving beam RS becomes smaller than the threshold value exceeds a reference number, the terminal may consider that the corresponding event has occurred.

[0120] For other events, the terminal can compare the measurements of the serving beam RS and the candidate beam RS(s) to observe event instances where the measurement of one candidate beam RS is greater than the measurement of the serving beam RS or greater than the measurement of the serving beam RS plus an offset. Here, the candidate beam RSs and the serving beam RSs belong to the same resource set so that their measurements can be compared under the same conditions. If event instances where the measurement of the serving beam RS is smaller than the measurement of the serving beam RS (or the measurement of the serving beam RS plus an offset) occur more than a reference number during a given period, the terminal may consider that the event has occurred. The number of occurrences of event instances can be counted for each of the candidate beam RSs.

[0121] In the case of another event, the terminal may detect an event instance where the measurement of a specific beam RS belonging to the indicated TCI states is smaller than a threshold value, based on the measurement of that beam RS. Here, the specific beam RS may be a beam RS corresponding to one of the TCI states active to the terminal. More specifically, the measurements of the beam RSs corresponding to the active TCI states are sorted in order of magnitude, and a beam RS (or TCI state) having the q-th magnitude may be derived. For convenience of explanation, this may be referred to as the "q-th beam RS." It is desirable that the RSs that can become this q-th beam RS belong to the same resource set. Their measurements are continuously compared, and the q-th beam RS may be continuously changed.

[0122] Meanwhile, events may also be configured for L1 / L2 trigger mobility (LTM), and below, events for LTM may be referred to as "LTM events".

[0123] A separate reporting setting is instructed to the terminal, and supported events can be measured by the terminal. The beam RS can be received from a specific serving cell (e.g., SpCell). If dual connectivity is established with the terminal, SpCell may refer to a serving cell (i.e., PCell or PUCCH-SCell) to which a PUCCH belonging to a master cell group or a secondary cell group can be transmitted.

[0124] In the case of certain events, the beam RS can be received from the SpCell, and may occur when the intensity of the beam RS is smaller than an absolute threshold value.

[0125] In the case of other events, beam RSs can be received from SpCell and candidate cells, and may occur when the strength of the beam RS received from the candidate cell is greater than the offset better than the strength of the beam RS received from SpCell.

[0126] In another event, it may occur when the strength of the beam RS received from the candidate cell is smaller than the absolute threshold value.

[0127] In another event, it may occur when the beam RS strength received from the SpCell is less than absolute threshold value 1, while the beam RS strength received from the candidate cell is greater than absolute threshold value 2.

[0128]

[0129] Information for configuring CSI reporting (CSI-ReportConfig) can be provided to terminals in an RRC connection state. The CSI reporting configuration (CSI-ReportConfig) determines the types of CSI (report quantity) that the CSI report must include, and the CSI can be measured in a CMR (channel measurement resource) set or an IMR (interference measurement resource) set.

[0130] FIG. 5 is a conceptual diagram illustrating the CSI reporting settings instructed to the terminal and the settings of CSI resources belonging to the CSI reporting settings.

[0131] Referring to FIG. 5, resources for signal measurement (channel measurement) may be referred to as a CMR set. A CMR set may include either a non-zero power (NZP) CSI-RS resource set or a CSI SSB resource set. Resources for interference measurement may be referred to as an IMR set. An IMR set may include either a non-zero power (NZP) CSI-RS resource set or a CSI SSB resource set, and a ZP CSI-RS resource set (i.e., a CSI-IM (interference measurement) resource set).

[0132] For the sake of convenience of explanation, a CSI report config may include one CMR set and, conditionally, one or fewer IMR sets. To change the CSI report config, an RRC reconfiguration is instructed to the terminal, which may change all or part of the information belonging to the CSI report config. However, since RRC signaling utilizes a DL-SCH (shared channel), a delay time equivalent to tens of slots is required.

[0133] To overcome this, a method may be considered in which CSI report settings corresponding to a large number of identifiers (CSI report IDs) are pre-instructed to the terminal, and the identifier of the CSI report setting corresponding to the required CSI report is dynamically instructed. However, this method entails a heavy burden of RRC signaling and L1 or L2 signaling required to instruct the identifier of the CSI report setting.

[0134] In the method proposed in the present disclosure, in the case of aperioditic reporting, since the trigger state and the CSI report ID are associated, a MAC CE may be used to add / change / remove the CSI report ID associated with the trigger state. The MAC CE may transmit the ID of the trigger state and the CSI report ID(s) to a terminal so that the terminal can update (or replace) the information represented by the trigger state.

[0135] In the method proposed in the present disclosure, a MAC CE can be used to add, change, or remove a CMR set and / or IMR set belonging to a CSI reporting setting. For convenience of explanation, the MAC CE for changing a CSI reporting setting may be referred to as the CSI MAC CE below. This method may be applied to periodic reports, and / or semi-persistent reports, and / or aperiodic reports.

[0136] It may not be possible to add, change, or remove all items in the CSI report settings using MAC CE. For example, the report quantity in the CSI report settings may not be changeable by MAC CE.

[0137] Referring to the CSI report settings, resources for signal measurement and resources for interference measurement can be distinguished. Resources for interference measurement can be further divided into interference measurement resources that utilize signals and interference measurement resources that do not utilize signals.

[0138] In the method proposed in the present disclosure, the terminal can change a CMR set or a CMR belonging to the CMR set by means of a MAC CE. A CMR set may consist of one or more CMRs. For convenience of explanation, the MAC CE for changing a CMR set or a CMR belonging to the CMR set may be referred to as a CMR MAC CE. The CMR MAC CE may be the same MAC CE as the previously described CSI MAC CE, but may be a separate MAC CE from the previously described CSI MAC CE.

[0139] A CMR MAC CE includes an identifier (CSI report id) of the target CSI report setting and may include a separate id to indicate the CMR or CMR set to be changed. The identifier of the CSI report setting may correspond to a candidate cell or a TRP (or an identifier of a TRP) belonging to the candidate cell. Alternatively, the identifier of the CSI report setting may correspond to another TRP (or an identifier of a TRP) belonging to the serving cell.

[0140] In one example of the proposed method, the separate ID can be interpreted as the ID of a CMR set. The terminal can be instructed to a list of CMR sets via RRC signaling and to be instructed to a CMR set to be changed via MAC CE. Regardless of the existing CMR set, the changed CMR set corresponding to the ID included in MAC CE can be applied to the CSI report.

[0141] Alternatively, a method of changing the CMR without changing the CMR set (or the size of the CMR set) may be preferred. In another example of the proposed method, the separate ID may be interpreted as the ID of the CMR. The terminal may be instructed to the CMR set via RRC signaling and to the CMR to be changed via MAC CE. Regardless of the existing CMR, the CMR corresponding to the ID included in the MAC CE may be applied to the CSI report.

[0142] The number of CMRs in the CMR set may not change. The number of IDs in the CMR set may not change, and the size of MAC CE may be constant.

[0143] The ID of the CMR may be given solely as the ID of the DL RS, as the ID of the DL RS and the frequency resource containing the DL RS, or correspond to the TCI state ID. That is, even if the ID of the CMR is not separately specified, it may be derived based on information in which the IDs of the DL RS are arranged in order according to the order of the CMR IDs, or based on information in which the IDs of the DL RS and the frequency resource or TCI state ID are arranged in order. To improve demodulation quality, the DL RS may be separately specified as qcl-typeA or qcl-typeA and qcl-typeD as TCI states. Here, to fix the number of CMRs belonging to the CMR set, the IDs of all CMRs may be included in the MAC CE in order.

[0144] If Carrier Aggregation (CA) is applied to the serving TRP, the frequency resource containing the DL RS may need to be indicated. The frequency resource containing the DL RS may correspond to the serving cell ID of the DL RS. The TCI state ID may refer to the TCI state that the terminal applies to the DL RS. The DL RS may be received from a candidate TRP rather than the serving TRP. In this case, an additional indicator may be used to distinguish whether the DL RS is received from the serving TRP or from the candidate TRP.

[0145] The TCI state indicated by the TCI state id can implicitly inform the terminal whether the DL RS is received by the serving TRP or by the candidate TRP. Additionally, there may be no need to distinguish whether the DL RS is received by the serving TRP or by the candidate TRP. The SSB or PCI derived from the TCI state may be the same as or different from the SSB or PCI of the serving TRP.

[0146] In the method proposed in the present disclosure, the terminal can change an IMR set or an IMR belonging to the IMR set by means of a MAC CE. An IMR set may consist of IMRs. For convenience of explanation, a MAC CE for changing an IMR set or an IMR belonging to the IMR set may be referred to as an IMR MAC CE. The IMR MAC CE may be the same MAC CE as the previously described CSI MAC CE, but may also be a MAC CE separate from the previously described CSI MAC CE.

[0147] Referring again to FIG. 5, the resource settings for interference measurement may differ from the resource settings for channel measurement. That is, the method for setting resources for channel measurement and the method for changing resources for channel measurement by MAC CE can be applied to resources for interference measurement as well, but there may be some differences due to the characteristics of the resources for interference measurement.

[0148] Resources for interference measurement can be divided into interference measurement resources (IMR-NZP) that transmit signals and interference measurement resources (IMR-ZP) that do not transmit signals. Resources that transmit signals may refer to resources capable of measuring signals received from a serving TRP or a candidate TRP. Resources that do not transmit signals may refer to resources capable of measuring only interference and noise under the assumption that the terminal is not mapped a DL signal / channel to the resource.

[0149] The previously described methods for adding, changing, or removing CMR or CMR sets may be applied to IMR-NZP or IMR-NZP sets. However, other methods based on the previously described methods may be applied to IMR-ZP or IMR-ZP sets.

[0150] IMR MAC CE includes a report ID and may include a separate ID to change the IMR (set).

[0151] In one example of the proposed method, the separate ID can be interpreted as the ID of the IMR set.

[0152] In one example of the proposed method, the separate ID mentioned above can be interpreted as the ID of the IMR.

[0153] IMR MAC CE may not change the DL RS type of the resource to which the signal is transmitted, and may only modify the ID of the same RS type.

[0154] The terminal may not specify a separate TCI state for IMR. The terminal may apply the TCI state for CMR (set) as is to the TCI state for IMR (set). For IMR (set), the information for qcl-type1 in the TCI state is unnecessary, but for qcl-type2 (qcl-typeD), the qcl-type2 of CMR (set) can be applied in the same way.

[0155]

[0156] When a MAC CE (CSI MAC CE, CMR MAC CE, and / or IMR MAC) for changing CSI reporting settings is received, the terminal may consider that the MAC CE is applied after a predetermined time (t) has elapsed since sending a HARQ-ACK to the serving TRP for the PDSCH containing the MAC CE (CSI MAC CE, CMR MAC CE, and / or IMR MAC CE).

[0157] CSI reports transmitted before a predetermined time t has elapsed may be derived using unchanged CSI report settings. CSI reports transmitted after a predetermined time t has elapsed may be derived using changed CSI report settings. Even if a new CMR set is indicated, the CSI reference resource that serves as the basis for the CSI report may be derived at a predetermined time before a PUSCH or PUCCH containing the CSI report is transmitted.

[0158] The terminal may not receive DL RS belonging to a CMR set and / or IMR set from a CSI reference resource that has occurred after a predetermined time t has elapsed.

[0159] In the method proposed in the present disclosure, the terminal may transmit the unupdated CSI report via PUSCH or PUCCH without updating the CSI report in such cases. The terminal may generate a valid CSI report only when it receives at least one DL RS in the CMR set and the IMR-NZP set.

[0160]

[0161] The terminal may perform periodic CSI reporting, semi-persistent CSI reporting, or non-periodic CSI reporting. The CSI reporting setting may indicate any one of these. Generally, CSI reporting is received at the terminal's serving TRP, but the present disclosure may not be limited thereto. When the terminal transmits CSI reporting using PUSCH or PUCCH, demodulation / decoding of the CSI reporting may be performed at the candidate TRP (or target TRP) as well as the serving TRP, depending on the TCI state.

[0162] When a non-periodic CSI report is performed, the terminal can receive scheduling information of the PUSCH to which the non-periodic CSI report is to be transmitted from the serving TRP or target TRP.

[0163] In one example, scheduling information for a PUSCH including non-periodic CSI reports can be derived from a DCI format. According to DCI format 0_0, DCI format 0_1, DCI format 0_2, or DCI format 0_3, a field for a CSI report trigger can be set. If the field has a specific value, the terminal can be instructed to transmit the CSI report via the PUSCH. In this case, the CSI report can be multiplexed with the UL-SCH.

[0164] In one example, scheduling information for a PUSCH containing a non-periodic CSI report may be derived from a MAC CE (hereinafter referred to as CSC (cell switch command) MAC CE). Consider cases where the PUSCH containing the non-periodic CSI report is a Msg3 PUSCH, or a PUSCH, or a configured grant PUSCH. A field for triggering the CSI report may be set in the RAR UL grant included in the Msg2 received by the terminal. If the field has a specific value, the terminal may be instructed to transmit the non-periodic CSI report via the PUSCH. In this case, the CSI report may be multiplexed with the UL-SCH. If the field has a different value, the terminal may transmit only the UL-SCH via the PUSCH and may not need to generate the CSI report.

[0165] The CSC MAC CE may include a TA to be applied to the UL signal / channel, an ID of the target TRP, an ID of the DL TCI state that is activated when scheduled at the target TRP, and / or an ID of the UL TCI state for the target TRP. Additionally, the CSC MAC CE may include RAPID (random access preamble index), PRACH mask, etc., as information for transmitting Msg1 to the target TRP, and such information may be used by the terminal to perform a CFRA (contention-free random access) procedure.

[0166] That is, referring again to FIG. 4, in step S440, the serving TRP can enable the terminal to perform the CFRA procedure with the target TRP by transmitting the CSC MAC CE to the terminal (S450).

[0167] FIG. 6 is a conceptual diagram illustrating the format of the CSC MAC CE applied to the embodiments of the present disclosure.

[0168] In the method proposed in the present disclosure, a field for a CSI report trigger may be included in the CSC MAC CE. If the field has a specific value, the terminal may be instructed to transmit an aperiodic CSI report through a UL signal / channel. That is, referring again to FIG. 4, if the field has a specific value, the terminal may transmit an aperiodic CSI report to a target base station through a UL signal / channel (S460).

[0169] In the method proposed in the present disclosure, the CSC MAC CE may not include scheduling information for the UL signal / channel. Upon receiving the CSC MAC CE, the terminal may transmit a PRACH preamble, and the target gNB may demodulate the PRACH preamble. In response to the PRACH preamble, the target gNB may transmit a random access response (RAR) to the terminal. The RAR may include scheduling information for the PUSCH. Since the terminal is instructed by the CSC MAC CE to multiplex the aperiodic CSI report and the UL-SCH into the PUSCH, the terminal may transmit the PUSCH in which the aperiodic CSI report and the UL-SCH are multiplexed. The target gNB may demodulate / decode the PUSCH received from the terminal.

[0170] In the method proposed in the present disclosure, the CSC MAC CE may include scheduling information for a UL signal / channel. When a terminal transmits a UL signal / channel, the UL signal / channel may be demodulated / decoded at a target TRP. Here, the UL signal / channel may be a PUCCH or a PUSCH.

[0171] In one example, the CSC MAC CE may include scheduling information related to the PUCCH. The resources for the PUCCH may be selected from the resource sets used prior to the common PUCCH resource set or the dedicated PUCCH resource set being directed to the terminal. The resource set may be the same as the resource set directed by the SIB1 of the target TRP.

[0172] According to conventional technical specifications, a PDCCH may include scheduling information for a PDSCH or a PUCCH. At least a CCE (control channel element) index may be derived so that a slot index in which a PUCCH can be transmitted and a resource for the PUCCH can be determined. Here, the CCE index may refer to a CCE index corresponding to the smallest index among the CCEs to which the PDCCH is mapped. Therefore, according to the proposed method, even when a PUCCH is transmitted according to a CSC MAC CE, information equivalent to a CCE index determining the time resource (slot index or slot offset) in which the PUCCH can be transmitted and / or the resource for the PUCCH may be included in the CSC MAC CE. For example, it may be indicated which subset the resource for the PUCCH belongs to within the aforementioned set of resources. Subsequently, in order to determine the resource index of the PUCCH, one resource belonging to the subset may be determined from the fields of the CSC MAC CE.

[0173] The time resource for which PUCCH can be transmitted can be interpreted based on the slot timing of the serving TRP or the slot timing of the target TRP. When the serving TRP transmits CSC MAC CE to the terminal, the terminal may consider this as a trigger for CSI reporting. The terminal may know the slot offsets of the serving TRP and the target TRP. When CSC MAC CE is received by the serving TRP, the slot of the target TRP corresponding to the slot of the serving TRP that received the CSC MAC CE can be determined based on the slot offset.

[0174] In one example, the CSC MAC CE may include scheduling information related to the PUSCH. The resources of the PUSCH may include all or part of the time resources (TDRA), frequency resources (FDRA), whether the PUSCH is frequency hopping, and power control (TPC).

[0175] After receiving the CSC MAC CE, the terminal can perform a CFRA procedure for the target TRP (step S460 of FIG. 4). The target TRP can receive a PRACH preamble according to the CFRA procedure and can transmit Msg2 to the terminal in response to the PRACH preamble. The terminal can receive Msg2, and Msg2 may include a RAR MAC CE. Scheduling information for the PUSCH may be included in the RAR MAC CE. The resources of the PUSCH may consist of time information, frequency information, MCS information, power information, CSI request information, etc.

[0176] Table 1 is a table for explaining the format of the RAR UL Grant applicable to the embodiments of the present disclosure.

[0177] RAR grant fieldbit numberFrequency hopping flag1PUSCH frequency resource allocation12, for operation with shared spectrum channel access in FR1 or for FR2-2 when ChannelAccessMode2-R17 is provided14, otherwisePUSCH time resource allocation4MCS4TPC command for PUSCH3CSI request1ChannelAccess-CPext2, for operation with shared spectrum channel access in FR1 or for FR2-2 when ChannelAccessMode2-R17 is provided0, otherwise

[0178] In the method proposed in the present disclosure, the terminal may derive a beta offset from all or part of the other fields constituting the scheduling information of PUSCH when the CSI request field of the RAR UL grant has a specific value. Here, the field(s) from which the beta offset is derived may be existing field(s) or new field(s) constituting the scheduling information of PUSCH.

[0179] According to conventional technical specifications, a beta offset can be used to calculate a relative ratio to the code rate of UL-SCH in order to determine the code rate of UCI when UCI is transmitted over PUSCH. Even if UL-SCH is not scheduled, the value corresponding to the code rate of UL-SCH can be used as a standard for deriving the code rate of UCI.

[0180] For example, part of the MCS field may mean both beta offset and MCS. For example, the MSB(s) of the MCS field may be interpreted as beta offset, and the LSB(s) of the MCS field may be interpreted as MCS. Or, the MSB(s) of the MCS field may be interpreted as MCS, and the LSB(s) of the MCS field may be interpreted as beta offset.

[0181] If the MCS field consists of 4 bits, 1 bit can be interpreted as the beta offset and the other 3 bits can be interpreted as the MCS. If the terminal receives CSI request information and needs to transmit a CSI report, the terminal can assume that the MCS is represented by 3 bits. If the terminal does not transmit a CSI report, the terminal can assume that the MCS is represented by 4 bits.

[0182] In the method proposed in the present disclosure, one value of the beta offset may be indicated to the terminal as RRC signaling and may not be indicated in the RAR UL grant. The code rate applied to the UCI is derived from the MCS indicated in the RAR UL grant, and the beta offset may be applied thereto. For example, the beta offset included in the serving cell configuration of a candidate cell indicated to the terminal may be reused. In such a case, even if a separate beta offset is not indicated, the terminal can derive the MCS applied to the UCI by applying the offset to the MCS applied to the PUSCH.

[0183]

[0184] In the method proposed in the present disclosure, a separate field indicating a beta offset may be added to the RAR UL grant. In one example, the field added to the RAR UL grant may indicate the beta offset alone. In one example, the beta offset may be indicated by a combination of the field added to the RAR UL grant and a conventional field. For example, when a terminal generates a CSI report because the CSI request field has a specific value, some of the values ​​from the added field and the conventional field may be used to derive the beta offset. For example, some of the MCS field and the added field may be used to derive the beta offset.

[0185]

[0186] The terminal may receive a CSI report trigger from the candidate TRP. Since the terminal has not established an RRC connection with the candidate TRP, the terminal may not be able to receive the CSI report trigger from the USS (UE-specific search space) set. Therefore, the CSI report trigger from the candidate TRP may be received by another means. The terminal may receive a response to Msg1 via Msg2. In one example, the terminal performing the LTM may not be instructed to repeat PUSCH (two or more times) during the step of performing a random connection (CBRA or CFRA) procedure with the candidate TRP.

[0187] In the method proposed in the present disclosure, the terminal can receive a CSI report trigger through a DCI format scrambled with TC-RNTI.

[0188] A specific field of the UL-related DCI format may be used to receive a CSI report trigger. In the method proposed in the present disclosure, a new field may be introduced in the DCI format 0_0 to indicate a CSI report trigger to the terminal. For example, if the field has a specific value, the terminal may be expected to generate a CSI report and piggyback the generated CSI report to PUSCH for transmission. If the field has a different value, the terminal may transmit only PUSCH without a CSI report.

[0189] In the method proposed in the present disclosure, when a CSI reporting trigger is directed to a terminal, the terminal may derive a CSI using periodic / semi-static CSI-RS and / or SSB. The terminal may not receive a non-periodic CSI-RS.

[0190] The terminal can receive instructions via upper-layer signaling for CSI reporting to the candidate TRP and settings for CSI-RS (and / or SSB). The serving TRP and the candidate TRP can exchange this information through the backhaul.

[0191] In one example, L1-RSRP can be derived using SSB or CSI-RS.

[0192] In one example, a wideband CSI report can be generated using CSI-RS.

[0193]

[0194] In the method proposed in the present disclosure, the TCI state may be indicated via a PDCCH order. In order for a terminal to transmit Msg1 to a candidate TRP or a serving TRP, the indicated TCI state may be used as information to derive a beam for transmitting Msg1.

[0195] To determine the recipient of Msg1 among the serving TRP or candidate TRPs, a specific field in DCI format 1_0 may be used. The field may have a size determined by the number of candidate TRPs. The field may include the identifier of the serving TRP or the identifier of the candidate TRP as an index.

[0196] In one example, the PDCCH order may include only the TCI state instead of the SSB identifier. The terminal can derive a beam for transmitting Msg1 from the TCI state.

[0197] In one example, the PDCCH order may include both the SSB identifier and the TCI state. The terminal can derive the ID of the target TRP and the RO (RACH occasion) applicable to CFRA using the cell indicator field, the SSB identifier, and the PRACH mask. Additionally, the SSB identifier may be used as the identifier of the TRP from which the TCI state is derived. The terminal can derive a beam for transmitting Msg1 by combining the cell indicator field and the SSB identifier with the TCI state.

[0198]

[0199] The terminal can receive CSI reporting triggers from the serving TRP. Specific fields of the UL-related DCI format may be used to receive CSI reporting triggers.

[0200] The candidate TRP transmitting the SSB and the serving TRP may belong to different CUs. The candidate TRP transmitting the CSI-RS and the serving TRP may belong to different CUs. When a terminal transmits a CSI report for the candidate TRP to the serving TRP, the serving TRP can forward the CSI report to the candidate TRP using backhaul. To do this, the CSI report configuration may include information about the candidate TRP's CU.

[0201] In the method proposed in the present disclosure, in addition to the PCI of the SSB, additional bits are added to indicate whether the CU of the candidate TRP and the CU of the serving TRP are the same or different.

[0202] In the method proposed in the present disclosure, in the information for setting the TCI state of CSI-RS, the ID of the candidate TRP may not be expressed solely by the physical cell identity (PCI). The identifier of the candidate TRP may use additional bits to indicate whether the CU of the candidate TRP and the CU of the serving TRP are the same or different.

[0203] In another example, even if the CU of the candidate TRP and the CU of the serving TRP are different, there may be no significant extension to the ID of the candidate TRP. The serving TRP can determine what information the corresponding CSI report is based on.

[0204] The above method may also be applied when the terminal receives a PDCCH order from the serving TRP. In this case, while performing the PDCCH order procedure for the candidate TRP, the terminal may receive information regarding whether the CU of the candidate TRP and the CU of the serving TRP are the same or different. This information may be provided by a combination of RRC signaling and DCI or by RRC signaling alone.

[0205] For example, the information in EarlyUL-SyncConfig may include information indicating whether the CU of the serving TRP and the CU of the candidate TRP are the same or different. In the PDCCH order, the existing cell indicator alone may not be sufficient to distinguish TRPs that have the same PCI while belonging to different CUs. Therefore, to prevent confusion in the terminal, additional information indicating whether the CU of the serving TRP and the CU of the candidate TRP are the same or different may be included.

[0206]

[0207] User-initiated (UE-initiated) CSI reports

[0208] In order to collect CSI more precisely and quickly in a 5G NR system, a method may be applied in which a terminal measures CSI and transmits a CSI report to a serving base station when event conditions are met. This method may be referred to as UE-initiated (UEI) CSI reporting.

[0209] A CMR set or IMR set may be configured for UEI CSI reporting. Event detection (ED)-RS resources may be associated with the CMR set. One or more events may be configured and activated for the terminal. The terminal may detect the occurrence of an event by observing the L1-RSRP measured using the ED-RS for a specified period of time. Each event condition may be defined based on a specific threshold. For example, an event instance may occur if the L1-RSRP of a specific beam drops below a threshold, or if the difference between the L1-RSRP of a specific beam and the L1-RSRP of another beam exceeds a threshold. If event instances occur more frequently than a specific threshold value during a configured period of time, the event may be considered detected. Here, a beam may correspond to an ED-RS, and a specific beam may correspond to an ED-RS derived from the TCI status of the physical channel currently scheduled for the terminal. In particular, a beam may correspond to an RS that provides qcl-typeD.

[0210] When an event is detected, the terminal begins preparing for CSI reporting and considers CPU occupancy during this process. If the detected event is reported immediately after detection, the terminal can use the measured L1-RSRP value of the ED-RS as is. Alternatively, if additional measurement is required for CSI reporting, the terminal can receive the ED-RS based on the CMR set, re-measure the L1-RSRP value of the ED-RS, and include the measured L1-RSRP value in the CSI report.

[0211] The method by which a terminal performs CSI reporting to a serving base station may be performed in one or two steps. In the case of a one-step process, for all or some of the ED-RSs belonging to the CMR set, the identifiers of the ED-RSs and their corresponding L1-RSRP values ​​may be included in a single physical channel and transmitted. In the case of a two-step process, the CSI reporting may consist of a step of notifying that an event has occurred and a step of transmitting the CSI report (i.e., a beam report).

[0212] Information indicating that an event has occurred may be related to the number of events configured in the terminal. When an event occurs, the terminal may report the occurrence of the event to the serving base station using PUCCH. For example, PUCCH format 0 or PUCCH format 1 may be used. In this case, one bit may indicate that one or more events have occurred.

[0213] CSI reports can be transmitted using PUSCH. The serving base station may enable the terminal to perform a CSI report using the CSI trigger field included in the DCI format. Alternatively, the serving base station may enable the terminal to transmit a CSI report using a configured grant PUSCH (e.g., Type-1 CG PUSCH).

[0214] The possibility of multiple events occurring simultaneously may also be considered. If multiple events occur simultaneously, the event priority levels may be utilized to determine whether only one event is reported or two or more events are reported. If the maximum amount of UCI required for reporting (e.g., PUSCH) is limited, some event(s) may not be reported.

[0215] A CPU resource occupancy model may be considered to maximize the efficiency of CSI reporting. CPU resources used for event detection and comparison (CPU1) and CPU resources utilized for configuring reporting information, including UCI generation (CPU2), can be distinguished. CPU resource occupancy can vary dynamically depending on the number of events, the number of measurement resources, the number of reporting items, and whether a PMI (precoding matrix indicator) is included in the CSI report.

[0216]

[0217] When UEI CSI reporting is performed in two stages, a first report (or first PUCCH report) and a second report (or second PUSCH report) may be used. These are transmitted through physical channels, and a priority index for each may be set or indicated.

[0218] According to conventional technical specifications, priority indices can be utilized in UL prioritization / multiplexing procedures. A terminal can apply UL prioritization / multiplexing procedures to UL signals / channels having the same priority index. Subsequently, the terminal can apply UL prioritization / multiplexing procedures to UL signals / channels having different priority indices.

[0219] In one example, the first report and the second report may always have the same priority index. Alternatively, the first report and the second report may always have the same low priority index. This may mean that the UEI-CSI report has a low priority.

[0220] In one example, a priority index may be set or directed in only one of the first report and the second report, and the other priority index may be implicitly considered to have the same value.

[0221] In one example, priority indexes may be set or directed independently for the first report and the second report, respectively. These may correspond to the same CSI report setting identifier but have different priority indexes.

[0222] In one example, a priority index may be specified in the CSI reporting settings. This means that the same priority index is applied to the first report and the second report.

[0223]

[0224] The terminal may transmit a second report after transmitting a first report. Depending on how the second report is triggered, the method of transmitting the second report can be classified into two methods.

[0225] In one example, the serving cell base station may transmit a scheduling DCI that assigns a PUSCH for a second report to the terminal in response to the first report. The terminal may transmit the second report on the assigned PUSCH. The above method is referred to as 'Mode A' below.

[0226] In one example, the serving cell base station sets a Type 1 CG PUSCH (or Type 2 CG PUSCH) to the terminal, and the terminal can select one of the Type 1 CG PUSCH (or Type 2 CG PUSCH) occasions and transmit a second report at the selected PUSCH occasion. The above method is referred to as 'Mode B' below.

[0227] The terminal may set (or be instructed) a time interval (e.g., X symbols) between the first report and the second PUCCH report. X may be a natural number greater than or equal to 0.

[0228] When X is a 0 symbol (X=0), the terminal can transmit the first report and the second report in the same slot. Therefore, the first report can be transmitted first in the same slot, and the second report can be transmitted later.

[0229] Since the first report and the second report may be transmitted from different serving cells, SCS1, which is the subcarrier spacing (SCS) of the BWP to which the first report is transmitted, and SCS2, which is the SCS of the BWP to which the second report is transmitted, may be different. In one example, the X symbol can be interpreted based on SCS1.

[0230] If X=0, the first report and the second report may be transmitted at the same symbol(s) within the same slot. In this case, the PUCCH for the first report and the PUSCH for the second report may overlap in time. Therefore, the terminal may multiplex the first report and the second report. The UL signal / channel in which the first report and the second report are multiplexed may be a CG PUSCH. Alternatively, the UL signal / channel in which the first report and the second report are multiplexed may be a PUSCH dynamically scheduled by the serving base station.

[0231] Therefore, in the PUSCH transmitted by the terminal, both the first report and the second report may be multiplexed and included. Here, the beta offset applied to the first report and the beta offset applied to the second report may be different from each other.

[0232] For example, the beta offset applied to the first report can be treated the same as HARQ-ACK and applied as a beta offset index applied to HARQ-ACK. For example, the beta offset applied to the second report can be treated the same as CSI and applied as a beta offset index applied to CSI.

[0233]

[0234] An LTM event can be determined based on SSB / CSI-RS received from the serving cell base station and the candidate cell base station. The terminal measures the L1-RSRP value (or L1-SINR value) based on the SSB / CSI-RS and can detect the occurrence of an LTM event based on the measured L1-RSRP value (or L1-SINR value). The terminal can report the occurrence of an LTM event to the serving cell base station. The terminal can transmit a MAC CE reporting the occurrence of an LTM event via PUSCH.

[0235] CSI reporting for a terminal to report LTM events and CSI reporting for a candidate cell base station (or a new serving cell base station) (e.g., CQI / PMI / RI, etc.) can be distinguished.

[0236] CSI reports for reporting LTM events are not transmitted to the serving cell base station as UCI, but may be transmitted to the serving cell base station via MAC CE. However, CSI reports transmitted to a new serving cell base station based on the reception of the CSC MAC CE may include CQI / PMI / RI to observe radio channel fading.

[0237] Therefore, the CPU (CSI processing unit) occupancy of CSI reporting for reporting LTM events and the CPU occupancy of CSI reporting for candidate cell base stations (or new serving cell base stations) (e.g., CQI / PMI / RI, etc.) can be distinguished.

[0238]

[0239] When a terminal is instructed by a serving cell base station to perform CSI reporting, the load on the terminal can be expressed quantitatively. Since the terminal has a limited number of CPUs due to a limited budget, it cannot process too many CSI reports simultaneously. According to technical specifications, the number of CPUs occupied can be derived based on the reportQuantity to be included in the CSI report.

[0240] The number of CSI reports that a terminal can simultaneously process for one or more component carriers at a specific time can be signaled via the upper-level parameter simultaneousCSI-ReportsPerCC or simultaneousCSI-SubReportsPerCC-r18. Additionally, the number of CSI reports that a terminal can simultaneously process across all component carriers can be signaled by simultaneousCSI-ReportsAllCC or simultaneousCSI-SubReportsAllCC-r18.

[0241] The terminal simultaneously If the terminal can process multiple CSI reports, It can be considered to be equipped with CPUs. In the process of processing CSI reports, if L CPUs are occupied on a single OFDM symbol, the terminal [is] with the remaining N CPUs can be utilized. At a specific point in time, N CSI reports occur simultaneously, and each of the N CSI reports If it is necessary to occupy CPUs, the terminal can select and process M CSI reports. Here, ... must be satisfied, and (MN) CSI reports that do not satisfy the condition may not be processed by the terminal. Additionally, the priority of the CSI reports can be derived from the technical specifications.

[0242]

[0243] Depending on the CSI reporting settings, the number of CPUs occupied by CSI reporting can be defined as follows.

[0244] If reportQuantity is set to 'none' and CSI-RS-ResourceSet is set to the parent parameter trs-Info It can be interpreted as.

[0245] If reportQuantity is 'cri-RSRP', 'ssb-Index-RSRP', 'cri-SINR', 'ssb-Index-SINR', 'cri-RSRP-Index', 'ssb-Index-RSRP-Index', 'cri-SINR-Index', 'ssb-Index-SINR-Index', or 'none' (trs-Info not set) or if ltm-CSI-ReportConfig is used It can be interpreted as.

[0246] reportQuantity is set to 'tdcp', and Y delays are configured by upper-layer parameters, and If the value is reported as the terminal's capability It can be interpreted as.

[0247] Cases where reportQuantity is set to one of 'cri-RI-PMI-CQI', 'cri-RI-i1', 'cri-RI-i1-CQI', 'cri-RI-CQI', or 'cri-RI-LI-PMI-CQI', and satisfies the following conditions may be additionally considered.

[0248] If max{μ_PDCCH, μ_CSI-RS, μ_UL}<=3, and the terminal transmits only a CSI report in a PUSCH that is triggered asynchronously by DCI, etc., and does not include a transmission block (TB) or HARQ-ACK, and L is 0, or if the CSI report is a single CSI with broadband frequency granulality and contains up to 4 CSI-RS ports within a single resource, there is no CRI report, and codebookType is set to typeI-SinglePanel or reportQuantity is set to cri-RI-CQI, It can be interpreted as.

[0249] If codebookType is set to 'typeI-SinglePanel' and the CMR set consists of two resource groups and N resource pairs, It can be interpreted as follows. Here, X is the number of CPUs occupied by the CMR pair, according to mTRP-CSI-numCPU-r17, and M can be derived according to the technical specifications.

[0250] If the CSI reporting configuration includes L sub-configurations provided by the upper layer via csi-ReportSubConfigToAddModList, for periodic CSI reporting It can be interpreted as (the number of resources corresponding to the i-th sub-configuration), and for non-permanent or semi-permanent CSI reports , It can be interpreted as.

[0251] If reportQuantity is set to 'cri-RI-PMI-CQI', codebookType is set to 'typeII-CJT-r18' or 'typeII-CJT-PortSelection-r18', and the associated NZP-CSI-RS-ResourceSet is In cases involving resources , It can be interpreted as follows. Here, X can be given as the capability of the terminal.

[0252] The case where reportQuantity is set to 'cri-RI-PMI-CQI' and codebookType is set to 'typeII-Doppler-r18' or 'typeII-Doppler-PortSelection-r18' can be considered. In this case, if the CMR set is configured non-periodically and includes K CSI-RS resources, depending on the value of K It can be interpreted differently. That is, if K=12 It can be interpreted as such, and if K<12, It can be interpreted as, It may be reported as the terminal's capability. Or, if the CMR set is configured periodically or semi-continuously and includes a single CSI-RS resource, Depending on It can be interpreted differently. That is, The other side It can be interpreted as, The other side It can be interpreted as and is composed of the upper layer parameter vectorLengthDD and It can be reported as the terminal's capability.

[0253] In other cases It is interpreted as, can be the number of resources in the CMR set.

[0254]

[0255] If the CSI report's reportQuantity is not 'none' or if the CSI report specified by LTM-CSI-ReportConfig is considered, the CPU occupancy time may be interpreted differently depending on the case.

[0256] For periodic or semi-persistent CSI reporting, the CPU may be occupied starting from the first symbol of the earliest transmission time among the related CSI-RS / CSI-IM / SSB resources, except for special cases such as 'SP-CSI on PUSCH' described below.

[0257] In the case of a periodic CSI report corresponding to a CSI report configuration containing a list of sub-configurations, the CPU may be occupied starting from the first symbol of each CSI-RS / CSI-IM resource associated with each sub-configuration. Alternatively, in the case of a semi-persistent CSI report corresponding to a CSI report configuration containing a list of sub-configurations, the CPU may be occupied starting from the first symbol of each CSI-RS / CSI-IM resource associated with each of all active or triggered sub-configurations.

[0258] The CSI-RS / CSI-IM / SSB mentioned herein must not be later than the CSI reference resource. The last symbol occupied by the CPU may contain the symbol of the very last CSI-RS / CSI-IM / SSB occupancy.

[0259] In the case of non-periodic CSI reporting, the CPU may be occupied from the first symbol following the PDCCH that triggers the CSI report to the last symbol of the PUSCH containing the CSI report. If PDCCH candidates exist in two sets of search spaces, the PDCCH candidate that terminates later may serve as the criterion for determining the CPU occupancy duration.

[0260] For the first transmitted semi-persistent CSI report, the CPU may be occupied from the first symbol following the PDCCH that triggers the semi-persistent CSI report until the last symbol of the PUSCH containing the CSI report. If PDCCH candidates exist in each of the two sets of search spaces, the PDCCH candidate that terminates later may serve as the criterion for determining the CPU occupancy duration.

[0261] For semi-persistent CSI reporting using Doppler-based codebooks ('typeII-Doppler-r18', etc.), not delayed compared to the CSI reference resource Among the consecutive periodic / semi-persistent CSI-RS occupies, the CPU may be occupied from the first symbol of the last occupancy to the last symbol of PUSCH containing the report. Here, It can be reported as the terminal's capability.

[0262] In the case of a CSI report according to a CSI report configuration associated with a CSI-RS-ResourceSet where the upper layer parameter reportQuantity is set to 'none' and the upper layer parameter trs-Info is not configured, the CPU may be occupied for a certain number of OFDM symbols. This condition may be met except for specific cases of semi-persistent CSI reports. For example, the above condition may be met except for the first semi-persistent CSI report transmitted via PUSCH after the PDCCH that triggers the semi-persistent CSI report.

[0263] In the case of an aperiodic CSI report (A-CSI report), CPU occupancy may begin from the first symbol following the PDCCH that triggers the CSI report. The OFDM symbol at which CPU occupancy ends is from the first symbol following the PDCCH. It may be a point in time after several symbols have elapsed, and also after the last symbol of the latest resource among each CSI-RS / SSB resource used for channel measurements for L1-RSRP calculation. It may be a point in time after several symbols have elapsed. The terminal can occupy the CPU until the later of these two points in time. Here The value may follow the value defined in the technical specifications and may be applied differently depending on the BWP's SCS.

[0264] In any slot, the terminal may be deemed not to possess more active CSI-RS ports or active CSI-RS resources than the value reported as capacity by the terminal within the active BWP. The active duration of an NZP CSI-RS resource may vary depending on whether the NZP CSI-RS resource is aperiodic CSI-RS, SP-CSI-RS, or P-CSI-RS.

[0265] For aperiodic CSI-RS, the active period may be defined as the interval from the end of the PDCCH triggering the CSI report to the end of the scheduled PUSCH containing the CSI report associated with the aperiodic CSI-RS. If the PDCCH candidates are associated with a search space set (SSS) composed of searchSpaceLinkingId, the active period of the NZP CSI-RS resource may be determined based on the PDCCH candidate with the later end time among the two linked PDCCH candidates.

[0266] In the case of SP-CSI-RS, the active period is defined as the interval from the end point when the activation command is applied to the end point when the deactivation command is applied.

[0267] In the case of periodic CSI-RS, the period from when the periodic CSI-RS is configured by upper-layer signaling until when the configuration of the CSI-RS is released can be defined as the active period.

[0268] If the same CSI-RS resource is referenced N times by one or more CSI reporting settings for which the upper-level parameter csi-ReportSubConfigToAddModList is not specified, the CSI-RS resource and the CSI-RS ports within it are counted as N times. Additionally, if a CMR set consists of two resource groups and N resource pairs, and the same CSI-RS resource is referenced X times by one or one or two resource pairs among the M CSI-RS resources mentioned in the technical specification, the CSI-RS resource and the CSI-RS ports within it are counted as X times.

[0269] A CSI report configuration including L sub-configurations provided by the upper layer via csi-ReportSubConfigToAddModList can be considered.

[0270] If, for a non-periodic CSI-RS resource, M of the N triggered sub-configurations reference the same CSI-RS resource, or for a periodic or semi-permanent CSI-RS resource, M of the L configured sub-configurations reference the same CSI-RS resource, the CSI-RS resource is calculated M times, and the number of CSI-RS ports within the resource It can be calculated as the larger value between and P.

[0271] Here, can mean the sum of the number of ports referenced by each of the M sub-configurations. Here, P can mean the number of ports configured by nrofPorts. Here is the number of CSI-RS ports included in the s-th subset. If portSubsetIndicator is configured, It is determined according to technical specifications, and in cases where otherwise, It can be considered as.

[0272] For periodic or semi-continuous CSI-RS resources for channel measurements associated with a CSI reporting setup where codebookType is set to typeII-Doppler-r18 or typeII-Doppler-PortSelection-r18, the said CSI-RS resource and its internal ports are It can be calculated as a double. Here, It can be indicated by the terminal's capability.

[0273] As described above, in conventional technical standards, the amount of CPU occupied, the symbol at which CPU occupancy begins, and the symbol at which CPU occupancy ends are clearly defined according to the trigger method and reportQuantity of CSI reporting.

[0274]

[0275] For UEI CSI reporting, the terminal receives CSI-RS / SSB from the serving cell base station and can perform measurements on the CSI-RS / SSB. After measuring the CSI-RS / SSB, the terminal can perform a report to the serving cell base station. Here, the terminal can observe whether event instances occur continuously for a predetermined period of time to detect events.

[0276] For example, if a specific event occurs to a terminal, the terminal may transmit a CSI report (e.g., a beam report) regarding the occurred event to a serving cell base station. Here, a first report reporting the occurrence of an event and a second report for the beam report may be distinguished. The terminal may transmit the first report using PUCCH and transmit the second report using PUSCH. For convenience of explanation, as described above, the first report and the second report may also be referred to as the first PUCCH report and the second PUSCH report, respectively.

[0277] For example, when a specific event occurs to a terminal, the terminal may multiplex a CSI report (e.g., beam report) regarding the occurred event with information related to the occurred event onto a single UL channel. The UL channel may be a PUSCH or a PUCCH.

[0278] To derive the first report, the terminal can measure CSI-RS / SSBs in the CMR (CMR / IMR) associated with the CSI report. Here, the number of CSI-RS / SSBs measured may be the number set by the CMR set. Both serving beam RSs and candidate beam RSs may be included in the same CMR set. The number of RSs belonging to the CMR set can be updated using RRC signaling or MAC CE. For convenience of explanation, the number of RSs belonging to the CMR set may be referred to as L.

[0279]

[0280] To derive a first report, the terminal may consider a CMR set associated with the CSI report. The terminal may repeatedly receive ED-RS(s) included in the CMR set. The terminal may determine whether the received ED-RS(s) satisfy a predetermined event occurrence condition. In this case, an evaluation occupation may be defined, and the terminal may determine whether the ED-RSs satisfy the event condition based on the evaluation occupation. The evaluation occupation may occur according to a predetermined evaluation period. For example, the evaluation occupation may have the same period as the period assigned to the CMR set. The evaluation occupation may be used as a framework to derive a single event instance for a specific event.

[0281] If event instances of a certain event occur above a threshold value within a specified time interval, the event may be considered to have been detected. This may be a trigger condition for the first report.

[0282] Once an event is detected, the terminal may no longer count the corresponding event instances. For example, even if the terminal receives an ED-RS, it may not count the corresponding event instances within the evaluation area, and the CPU for that evaluation area may no longer be occupied. After transmitting the first report, the terminal may derive new event instances by performing a measurement on the ED-RS again. For example, the first report may be mapped to PUCCH, but the first report may not be transmitted through PUCCH while the terminal is transmitting another UL signal / channel (i.e., the first report is dropped). Even if the terminal fails to transmit the first report, once the first report is generated, the terminal's above-described behavior regarding the ED-RSs may be applied in the same way.

[0283]

[0284] The terminal may be instructed by the serving base station to perform either Mode A or Mode B as described above.

[0285] FIGS. 7 to 12 are conceptual diagrams for explaining UEI CSI reporting operations according to embodiments of the present disclosure.

[0286] Specifically, FIGS. 7 and 8 illustrate the case where the terminal operates in Mode A, and FIGS. 9 through 12 illustrate the case where the terminal operates in Mode B. Referring to FIGS. 7 through 12, the terminal may occupy the CPU immediately before the evaluation occupancy of the ED-RS. Accordingly, the terminal's occupation of the CPU may end when an event is detected, regardless of whether the first report is transmitted.

[0287] However, the time at which the terminal's CPU occupancy starts / ends for the second report may differ between Mode A and Mode B.

[0288] Referring to FIGS. 7 and FIGS. 8, in Mode A, the terminal's CPU may be occupied again after the terminal receives a UL grant that allocates a PUSCH resource for transmitting a second report.

[0289] Meanwhile, in Mode B, since the second report is transmitted using CG PUSCH, the time at which CPU occupancy begins / ends may differ.

[0290] As illustrated in FIGS. 9 and 10, in one embodiment, the CPU may be occupied only immediately before PUSCH is transmitted. As illustrated in FIGS. 11 and 12, in another embodiment, the CPU may be continuously occupied from after an event is detected until PUSCH is transmitted.

[0291]

[0292] In one example, the application of CSI reference resources may be required for the second report generated by the terminal. Regardless of Mode A and Mode B, CSI reference resources applied to non-periodic CSI reports may be applied to the second report. In this case, the start and end of CPU occupancy may be interpreted differently.

[0293] In another example, the CSI reference resources applied to the second report generated by the terminal may differ in Mode A and Mode B. In Mode A, since the operation of transmitting the second report is a subsequent operation under the UL grant, the CSI reference resources applied to non-periodic CSI reports may be applied to the second report. In Mode B, since the second report is transmitted via CG PUSCH, the CSI reference resources applied to semi-persistent CSI reports or periodic CSI reports may be applied to the second report.

[0294] In another example, the CSI reference resource may be explicitly applied only to the second report. In this case, the terminal may apply the CSI reference resource to the first report in an implementation manner. That is, the CSI reference resource defined in the standard is not applied, and the terminal may derive the first report and the second report according to certain conditions.

[0295]

[0296] To derive the first report, the terminal may measure L RSs. When measuring L1-RSRP values, L CPUs may be counted as occupied. When measuring L1-SINR, L CPUs may be counted as occupied. Alternatively, when measuring L1-RSRP values, a fixed number of CPUs may be counted regardless of L. For example, it may be assumed that 1 CPU is occupied. That is, CPU occupancy may not increase proportionally to L even if the terminal measures L RSs. This is because the terminal's memory is consumed at a constant rate the moment a CPU is occupied. Therefore, the number of occupied CPUs can be counted as a fixed value regardless of L. Furthermore, even when the terminal is instructed to perform group-based reporting, the terminal's memory occupancy may have a constant value regardless of the size of L.

[0297] The symbol at which the terminal begins to occupy the CPU may be the first received RS among the RSs belonging to the CMR set. If the RS has multiple symbols, CPU occupancy may begin at the first symbol of that RS.

[0298] The symbol at which the terminal ends its CPU occupation may be the last symbol at which the terminal transmitted the first report. When the first report is transmitted, the symbol at which the terminal ends its CPU occupation may be the last symbol of the PUCCH containing the first report. If the first report is transmitted multiplexed with another UL signal / channel, the symbol at which the terminal ends its CPU occupation may be the last symbol of the corresponding UL signal / channel.

[0299] If a case occurs where the first report is not transmitted, the terminal may assume that the first report has been transmitted and end CPU occupancy at the last symbol of the UL signal / channel where the first report was transmitted. The case where the first report is not transmitted may be when the transmission resources for the first report are pre-empted by a UL signal / channel having a higher priority than the first report during the terminal's UL priority / multiplexing procedure. Alternatively, the case where the first report is not transmitted may be when the terminal detects another event and is unable to transmit a new first report because it is already transmitting a first report for that event.

[0300] After transmitting the first report, the terminal may receive a dynamic instruction (UL grant) from the serving cell base station and transmit a PUSCH from a scheduled resource or transmit using an already configured PUSCH. The configured PUSCH may be a Type 1 CG PUSCH or a Type 2 CG PUSCH.

[0301] The second report may include L1-RSRP (or L1-SINR) values ​​for a selected number of RSs as a beam report. The second report may have a form in which CRIs (or SSBRIs) and their respective corresponding L1-RSRPs (or L1-SINRs) are arranged. Here, the beam report may be considered as a UCI and may be piggybacked to PUSCH by applying polar coding.

[0302] Here, the selected number may be a value derived from the corresponding CSI report settings. The length of the UCI (or amount of payload) may be indicated to the terminal via RRC signaling. For convenience of explanation, the number of beam RSs containing L1-RSRP (or L1-SINR) values ​​in the second report may be M.

[0303] In one example, the number of beam RSs observed for the first report (L) and the number of beam RSs included in the second report (M) may not necessarily be the same. L may be greater than M, but may also be smaller.

[0304] In one example, the serving cell base station may instruct the terminal to include only information about some of the beam RSs used for event detection in the beam report. In one example, for scheduling convenience, the serving cell base station may instruct the terminal to include information about beam RSs not used for event detection in the beam report as well.

[0305] When the terminal reports on M beam RSs through a second report, if M L1-RSRP values ​​are reported, M CPUs may be counted as occupied. When the terminal reports on M beam RSs through a second report, if M L1-SINR values ​​are reported, M CPUs may be counted as occupied. Alternatively, even if M L1-RSRP values ​​or M L1-SINR values ​​are reported, a number of CPUs unrelated to M may be counted as occupied. For example, 1 CPU may be counted as occupied.

[0306] That is, the CPU may be occupied because the terminal can perform measurements separate from the measurements for the first report for beam reporting for the second report. That is, regarding the time resources for which the second report is to be transmitted, CSI reference resources may be considered, and the terminal can update L1-RSRP values ​​(or L1-SINR values) related to the beam RSs included in the second report.

[0307]

[0308] The symbol at which the terminal begins to occupy the CPU may be the first received RS within the same period among the RSs belonging to the CMR set. If the RS has multiple symbols, CPU occupancy may begin from the first symbol of the RS.

[0309] The symbol at which the terminal ends its occupation of the CPU may be the last symbol at which the terminal transmitted the first report. If the first PUCCH report is transmitted, it may be the last symbol of the PUCCH. If the first report is multiplexed with another UL signal / channel, it may be the last symbol of that UL signal / channel.

[0310] If a case occurs where the first report is not transmitted, the terminal may assume that the first report has been transmitted and end CPU occupancy at the last symbol of the UL signal / channel where the first report was transmitted. Here, the case where the first report is not transmitted is because it may be pre-empted by a UL signal / channel having a higher priority than the first report during the terminal's UL prioritization / multiplexing process. Alternatively, the terminal may be unable to transmit a new first report because it has detected another event and is already transmitting a first report for it.

[0311] The case where the second report is transmitted via a PUSCH transmitted using dynamic scheduling and the case where the second report is transmitted via a PUSCH transmitted using a configuration grant may have different CPU occupancy times.

[0312] For example, in the case of dynamic scheduling, CPU occupancy may begin after the UL grant is received.

[0313] For example, when scheduling by configuration grant, the symbol at which the terminal's CPU occupancy begins may not be clearly defined. In such cases, the first report and the second report may be considered to be linked. That is, the CPU occupancy is not considered to have ended after the first report is transmitted, but rather may be considered to have ended after the second report is transmitted.

[0314] Alternatively, when scheduled by a configuration grant, the CPU occupancy for generating the second report may be derived from the time resources expected to be transmitted for the second report. Even if the second report is dropped, the terminal may assume that the CPU occupancy for the second report begins and ends. The terminal may assume that the second report is transmitted in the first CG PUSCH that occurs after a predetermined time (X symbols) has elapsed since the first report, and may consider the processing time for it. If the second report is dropped, the terminal may not retransmit the second report.

[0315] Alternatively, if scheduled by a configuration grant, the CPU occupancy for generating the second report may be derived from the time resources at which the second report is transmitted. When a terminal transmits the second report using a Type 1 CG PUSCH, the terminal may select the first PUSCH at which the second report can be generated. The PUSCH may be a PUSCH that occurs after a predetermined time (X symbols) has elapsed since the transmission of the first report. If the first PUSCH that occurs to the terminal after a predetermined time has elapsed since the transmission of the first report is valid, the terminal may transmit the second report at that PUSCH.

[0316] The corresponding PUSCH may not always be valid. For example, the CG PUSCH may be dropped in order for the terminal to transmit a different UL signal / channel. For example, when a scheduling request (SR) occurs, the terminal may drop the CG PUSCH and transmit only the SR using the PUCCH. In this case, the PUCCH and the CG PUSCH may overlap in time. For example, the CG PUSCH may be dropped in order to transmit a UL signal / channel with a higher priority index. For example, if two or more CG PUSCHs occur to the terminal at the same time, the terminal may select one of the CG PUSCHs. Here, the CG PUSCH that does not include the second report may be selected.

[0317] Accordingly, the terminal can predict the time resources of the CG PUSCH where the second report can be transmitted, and start and end the CPU occupation based on the predicted time resources.

[0318]

[0319] The serving cell base station may instruct the terminal to include additional information in the second report separately from the beam report. For example, the additional information may be 1-bit information indicating whether each beam RS satisfies an event condition. In this case, the terminal may generate a second report with M bits added for the M beam RSs considered in the second report. For example, for a candidate beam RS having an L1-RSRP value (or L1-SINR value) greater than the value obtained by applying an offset to the L1-RSRP value (or L1-SINR value) of the serving beam RS, the corresponding bit may have a first value, and otherwise, the corresponding bit may have a second value.

[0320] The point in time at which the terminal derives additional information may be derived from the time resource at which the second report is transmitted. For example, the CSI reference resource for the PUSCH at which the second report is transmitted may be considered. The terminal may assume that at that point in time, the L1-RSRP value (or L1-SINR value) and the threshold (or the sum of the threshold and the offset) for the candidate beam RS are compared.

[0321] In one example, CPU occupation may not be performed to derive additional information. Since the additional information is derived by a simple operation comparing the L1-RSRP value (or L1-SINR value) with a specific value (i.e., a threshold value or the sum of the threshold value and the offset), separate additional CPU occupation may not be assumed.

[0322] In one example, the CPU may be occupied to derive additional information. This is because the CPU can be occupied even for a simple operation of comparing an L1-RSRP value (or L1-SINR value) with a specific value. In this case, it can be assumed that the CPU is occupied regardless of the size of the CMR set, the number of CSI-RS / SSBs to be included in the second report, or the number of CSI-RS / SSBs to be considered in the additional information.

[0323] In one example, if the terminal is instructed to derive additional information, the terminal may not update the L1-RSRP value (or L1-SINR value) considering the CSI reference resource in order to generate a second report. In such a case, the terminal may be permitted to use the L1-RSRP value (or L1-SINR value) derived during the process of generating the first report as is. The additional information may be derived by the terminal by assuming a CSI reference resource considering the time when the second report is transmitted.

[0324] In one example, additional information is included in the second report but may be generated from the terminal without separate restrictions. In such cases, the additional information may be independent of CSI reference resources or may also be independent of CPU occupancy.

[0325] When a terminal occupies the CPU while including additional information in the second report, the CPU may be occupied from the first symbol where the CPU occupancy for generating the second report begins until the last symbol where the CPU occupancy ends after transmitting the second report.

[0326]

[0327] As previously described, a terminal's CSI report can be triggered via CSC MAC CE. Alternatively, a terminal's CSI report can be triggered by a RAR UL grant scheduling PUSCH or a DCI format 1_0 scrambled with TC-RNTI.

[0328] Alternatively, a CG PUSCH transmitted by the terminal to a candidate cell base station may be considered. The CSI report may be multiplexed in the said CG PUSCH. In principle, the terminal may transmit the CG PUSCH only to the serving cell base station, but in specific situations, the terminal may transmit the CG PUSCH to a candidate cell base station. In this case, which base station (serving cell base station or candidate cell base station) the terminal should transmit the CG PUSCH to can be clearly distinguished by being indicated via the CSC MAC CE or by the serving cell being changed through the RRC connection reset procedure (exchange of request and completion messages). That is, the terminal always transmits the CG PUSCH to the serving cell base station, and if necessary, the serving cell base station may be changed to the candidate cell base station.

[0329] When a terminal uses a CG PUSCH, it may select the first available PUSCH to transmit a CSI report. However, in this case, the transmitted CSI report may or may not be valid. This is because, since the terminal must use a CG PUSCH to exchange RRC signaling with a new serving cell base station, the CSI report itself is triggered, but the terminal may not be given sufficient preparation time.

[0330] In such cases, the new serving cell base station may not be able to determine if the CSI report is valid because UL skipping may frequently occur in the CG PUSCH. Alternatively, the candidate cell base station may not yet have sufficient information about the terminal because the terminal detects an LTM event and performs RACH-less LTM to the candidate cell base station, using the CG PUSCH in the process.

[0331] Some of the reportQuantity included in the CSI report may be used to determine the validity of the CSI report. Here, reportQuantity may refer to CRI / RI / PMI / CQI. In one example, if specific value(s) of CQI are received by a candidate cell base station (or a new serving cell base station), the corresponding CSI report may be interpreted as invalid.

[0332] The terminal may occupy the CPU to generate the corresponding CSI report. The symbol at which the CPU occupation ends may be the last symbol of the UL signal / channel through which the CSI report is transmitted.

[0333] The symbol at which CPU occupancy begins may vary depending on the interpretation that initiates the action to prepare the CSI report.

[0334] In one example, CPU occupancy may begin after receiving a CSC MAC CE from the serving cell base station and transmitting a HARQ-ACK in response. This is because the terminal may consider the receipt of the CSC MAC CE as the trigger for the CSI report. That is, the terminal may need to monitor the CMR set at least, and CPU occupancy may be considered constant or may begin from the trigger point when the CMR set begins to be observed. Additionally, CPU occupancy may end when the terminal receives the CSC MAC CE.

[0335] The terminal can distinguish between CPU occupancy for monitoring LTM events and CPU occupancy for the candidate cell base station (or new serving cell base station). In other words, the terminal requires CPU occupancy to measure L1-RSRP (or L1-SINR) in order to monitor LTM events, and since the CSI report for the new serving cell base station can derive CRI / RI / PMI / CQI by receiving a separate CSI-RS.

[0336] In one example, CPU occupancy may begin after receiving Msg2 PDSCH from the existing serving cell base station or the new serving cell base station (or candidate cell base station) (or after decoding Msg2 PDSCH). This is because the terminal may include a CSI report while transmitting the PUSCH.

[0337] In one example, the terminal may start occupying the CPU based on the CG PUSCH that it first transmits to a new serving cell base station (or candidate cell base station). Here, a CSI report is generated taking into account the preparation time for processing the CG PUSCH, and the CPU may be occupied from that time.

[0338] In one example, a CMR set may be instructed to generate the CSI report initially transmitted to a new serving cell base station (or candidate cell base station). Therefore, CPU occupancy may begin from the moment the CMR set is activated. This may be the point at which the CSC MAC CE is transmitted to the serving cell base station, or it may not be separately defined in the technical specifications. This is because the point at which the terminal begins CSI measurement by transmitting the SSB / CSI-RS from the new serving cell base station may not be clear.

[0339]

[0340] The operation of the method according to an embodiment of the present invention can be implemented as a computer-readable program or code on a computer-readable recording medium. A computer-readable recording medium includes all types of recording devices in which information that can be read by a computer system is stored. Additionally, the computer-readable recording medium may be distributed across networked computer systems, allowing computer-readable programs or code to be stored and executed in a distributed manner.

[0341] In addition, computer-readable recording media may include hardware devices specifically configured to store and execute program instructions, such as ROM, RAM, and flash memory. Program instructions may include machine code, such as that generated by a compiler, as well as high-level language code that can be executed by a computer using an interpreter, etc.

[0342] Some aspects of the invention have been described in the context of a device, but may also be described according to a corresponding method, wherein a block or device corresponds to a method step or a feature of a method step. Similarly, aspects described in the context of a method may also be described according to a corresponding block or item or a feature of a corresponding device. Some or all of the method steps may be performed by (or using) a hardware device, such as, for example, a microprocessor, a programmable computer, or an electronic circuit. In some embodiments, at least one of the most important method steps may be performed by such a device.

[0343] In the embodiments, a programmable logic device (e.g., a field-programmable gate array) may be used to perform some or all of the functions of the methods described herein. In the embodiments, the field-programmable gate array may operate with a microprocessor to perform one of the methods described herein. Generally, it is preferable that the methods be performed by some hardware device.

[0344] Although the present invention has been described with reference to preferred embodiments, those skilled in the art will understand that various modifications and changes can be made to the invention without departing from the spirit and scope of the invention as described in the following claims.

Claims

1. By means of a terminal, A step of receiving setting information for measuring channel state information (CSI) from a first cell; Based on the above setting information, a step of generating a CSI from a downlink (DL) reference signal (RS) received from a second cell; A step of receiving a first MAC (medium access control) CE (control element) from the first cell; and Based on the first MAC CE, the method comprises the step of transmitting a CSI report containing the generated CSI to the second cell. method.

2. In Claim 1, The first cell above is a serving cell, and the second cell above is a lower-layer triggered mobility (LTM) candidate cell, method.

3. In Claim 2, The first cell and the second cell are operated by the same central unit (CU) of the same base station, operated by different CUs of the same base station, or operated by different CUs of different base stations. method.

4. In Claim 1, The above configuration information includes a CSI report configuration and a CSI resource configuration, wherein the CSI resource configuration includes at least one of a set of at least one channel measurement resource (CMR) or a set of at least one interference measurement resource (IMR). method.

5. In Claim 4, A step of receiving a second MAC CE from the first cell for adding, updating, or releasing attributes of at least one CMR set, a CMR resource belonging to the at least one CMR set, or a CMR resource belonging to the at least one CMR set; and The method further includes the step of adding, updating, or deleting the attributes of the at least one CMR set, the CMR resource belonging to the at least one CMR set, or the CMR resource belonging to the at least one CMR set, based on the above second MAC CE. The addition, updating, or deletion of a CMR resource belonging to the at least one CMR set or an attribute of a CMR resource belonging to the at least one CMR set is performed by the addition, updating, or deletion of a TCI (transmission configuration indicator) status identifier corresponding to the CMR resource belonging to the at least one CMR set or an attribute of a CMR resource belonging to the at least one CMR set. method.

6. In Claim 4, A step of receiving a second MAC CE from the first cell for adding, updating, or releasing attributes of at least one IMR set, a CMR resource belonging to the at least one IMR set, or an IMR resource belonging to the at least one IMR set; and The method further includes the step of adding, updating, or removing attributes of at least one IMR set, an IMR resource belonging to the at least one IMR set, or an IMR resource belonging to the at least one IMR set based on the above second MAC CE. The addition, updating, or deletion of an IMR resource belonging to the at least one IMR set or an attribute of an IMR resource belonging to the at least one IMR set is performed by the addition, updating, or deletion of a TCI (transmission configuration indicator) status identifier corresponding to the IMR resource belonging to the at least one IMR set or an attribute of an IMR resource belonging to the at least one IMR set. method.

7. In Claim 1, The above CSI report is transmitted to the second cell via a PUSCH (physical uplink shared channel) within a random access (RA) procedure for the second cell, method.

8. In Claim 7, The modulation and coding scheme (MCS) applied to the above CSI report is determined based on at least one field among the uplink (UL) grant fields included in the random access response (RA) Msg2 (message 2) received from the first cell within the RA procedure, and the beta offset for determining the code rate of the above CSI report is received via radio resource control (RRC) signaling, method.

9. By the method of the first base station, A step of transmitting configuration information for measuring channel state information (CSI) to a terminal through a first cell operated by the first base station; and The method includes the step of transmitting a first MAC (medium access control) CE (control element) to the terminal through the first cell, and The first MAC CE causes the terminal to transmit to the second cell a CSI report including a CSI derived from a downlink (DL) reference signal (RS) of the second cell operated by the first base station or a second base station different from the first base station, method.

10. In Claim 9, The first cell above is a serving cell, and the second cell above is a lower-layer triggered mobility (LTM) candidate cell, method.

11. In Claim 9, The above configuration information includes a CSI report configuration and a CSI resource configuration, wherein the CSI resource configuration includes at least one of a set of at least one channel measurement resource (CMR) or a set of at least one interference measurement resource (IMR). method.

12. In Claim 11, The method further includes the step of transmitting a second MAC CE to the terminal through the first cell for adding, changing, or releasing attributes of the at least one CMR set, the CMR resource belonging to the at least one CMR set, or the CMR resource belonging to the at least one CMR set. The addition, updating, or deletion of a CMR resource belonging to the at least one CMR set or an attribute of a CMR resource belonging to the at least one CMR set is performed by the addition, updating, or deletion of a TCI (transmission configuration indicator) status identifier corresponding to the CMR resource belonging to the at least one CMR set or an attribute of a CMR resource belonging to the at least one CMR set. method.

13. In Claim 11, The method further includes the step of transmitting a second MAC CE to the terminal through the first cell for adding, changing, or releasing attributes of the at least one IMR set, the CMR resource belonging to the at least one IMR set, or the IMR resource belonging to the at least one IMR set. The addition, updating, or deletion of an IMR resource belonging to the at least one IMR set or an attribute of an IMR resource belonging to the at least one IMR set is performed by the addition, updating, or deletion of a TCI (transmission configuration indicator) status identifier corresponding to the IMR resource belonging to the at least one IMR set or an attribute of an IMR resource belonging to the at least one IMR set. method.

14. In Claim 10, The above CSI report is transmitted to the second cell via a physical uplink shared channel (PUSCH) within a random access (RA) procedure for the second cell, method.

15. In Claim 14, The modulation and coding scheme (MCS) applied to the above CSI report is determined based on at least one field among the uplink (UL) grant fields included in the random access response (RA) Msg2 (message 2) transmitted from the first cell within the above RA procedure, and the beta offset for determining the code rate of the above CSI report is transmitted via radio resource control (RAC) signaling, method.

16. A terminal comprising at least one processor, The above at least one processor is the terminal: A step of receiving setting information for measuring channel state information (CSI) from a first cell; Based on the above setting information, a step of generating a CSI from a downlink (DL) reference signal (RS) received from a second cell; A step of receiving a first MAC (medium access control) CE (control element) from the first cell; and Based on the first MAC CE above, performing the step of transmitting a CSI report including the generated CSI to the second cell. Terminal.

17. In Claim 16, The first cell above is a serving cell, and the second cell above is a lower-layer triggered mobility (LTM) candidate cell, Terminal.

18. In Claim 16, The above configuration information includes a CSI report configuration and a CSI resource configuration, wherein the CSI resource configuration includes at least one of a set of at least one channel measurement resource (CMR) or a set of at least one interference measurement resource (IMR). Terminal.

19. In Claim 18, The above at least one processor is the terminal: A step of receiving a second MAC CE from the first cell for adding, updating, or releasing attributes of at least one CMR set, a CMR resource belonging to the at least one CMR set, or a CMR resource belonging to the at least one CMR set; and Based on the above second MAC CE, additionally perform the step of adding, updating, or removing the attributes of the at least one CMR set, the CMR resource belonging to the at least one CMR set, or the CMR resource belonging to the at least one CMR set. The addition, updating, or deletion of a CMR resource belonging to the at least one CMR set or an attribute of a CMR resource belonging to the at least one CMR set is performed by the addition, updating, or deletion of a TCI (transmission configuration indicator) status identifier corresponding to the CMR resource belonging to the at least one CMR set or an attribute of a CMR resource belonging to the at least one CMR set. Terminal.

20. In Claim 18, The above at least one processor is the terminal: A step of receiving a second MAC CE from the first cell for adding, updating, or releasing attributes of at least one IMR set, a CMR resource belonging to the at least one IMR set, or an IMR resource belonging to the at least one IMR set; and Based on the above second MAC CE, additionally perform the step of adding, updating, or removing the attributes of the at least one IMR set, the IMR resource belonging to the at least one IMR set, or the IMR resource belonging to the at least one IMR set. The addition, updating, or deletion of an IMR resource belonging to the at least one IMR set or an attribute of an IMR resource belonging to the at least one IMR set is performed by the addition, updating, or deletion of a TCI (transmission configuration indicator) status identifier corresponding to the IMR resource belonging to the at least one IMR set or an attribute of an IMR resource belonging to the at least one IMR set. Terminal.

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