Method and apparatus for power control based on path loss compensation in asymmetric TRP system

Abstract

Disclosed are a method and an apparatus for power control based on path loss compensation in an asymmetric TRP system. The method of a user equipment (UE) comprises the steps of: performing downlink (DL) communication with a first transmission and reception point (TRP); determining a first uplink (UL) transmission power for a first UL communication with the first TRP on the basis of a state of a DL channel between the UE and the first TRP; performing the first UL communication with the first TRP by using the first UL transmission power; determining a second UL transmission power for a second UL communication with a second TRP on the basis of the state of the DL channel between the UE and the first TRP and a power offset; and performing the second UL communication with the second TRP by using the second UL transmission power.

Description

Method and device for power control based on path loss compensation in an asymmetric TRP system

[0001] The present disclosure relates to improved communication technology, and more particularly, to a power control technology based on path loss compensation in a communication system supporting asymmetric transmission and reception points (TRPs).

[0002] Communication networks (e.g., 5G communication networks, 6G communication networks, etc.) are being developed to provide improved communication services compared to existing communication networks (e.g., long term evolution (LTE), advanced LTE-A (LTE-A), etc.). 5G communication networks (e.g., new radio (NR) communication networks) can support frequency bands above 6 GHz as well as frequency bands below 6 GHz. That is, 5G communication networks can support FR1 bands and / or FR2 bands. 5G communication networks can support various communication services and scenarios compared to LTE communication networks. For example, usage scenarios of 5G communication networks can include enhanced Mobile Broadband (eMBB), Ultra Reliable Low Latency Communication (URLLC), massive Machine Type Communication (mMTC), etc.

[0003] Compared to 5G, 6G communication networks can support a wider range of communication services and scenarios. 6G communication networks can meet requirements for ultra-high performance, ultra-high bandwidth, ultra-high space, ultra-high precision, ultra-intelligence, and / or ultra-reliability. 6G communication networks can support diverse and wide frequency bands and be applied to various usage scenarios (e.g., terrestrial communications, non-terrestrial communications, sidelink communications, etc.).

[0004] Meanwhile, multiple transmission and reception points (mTRPs) can be introduced into communication networks (e.g., 5G and / or 6G). mTRPs can be geographically separated. Base stations can use mTRPs to communicate with terminals. mTRP technology can be used to address quality of service (QoS) degradation issues for cell-edge terminals and / or inter-cell interference issues. mTRP technology can also be used to provide additional communication paths in environments where non-line-of-sight (NLOS) paths are limited.

[0005] mTRP-based communication can be performed based on either the coherent joint transmission (CJT) scheme or the non-CJT (NCJT) scheme. In the CJT scheme, mTRP can perform cooperative communication based on a stable backhaul link and provide synchronized communication services to terminals. In the NCJT scheme, mTRP can provide communication services to terminals without cooperation. For example, in the NCJT scheme, mTRP can perform scheduling operations, precoding matrix selection operations, and modulation and coding scheme (MCS) determination operations without cooperation.

[0006] In an asymmetric TRP system, a terminal can perform sTRP and DL (downlink) communications, and a terminal can perform mTRP and UL (uplink) communications. In this case, if UL communications for mTRP are performed using the same transmission power, the terminal's power consumption may increase, and interference caused by UL communications may increase. A method for determining transmission power to address this issue is needed.

[0007] The purpose of the present disclosure to solve the above problems is to provide a method and device for power control based on path loss compensation in a communication system supporting an asymmetric TRP (transmission and reception point).

[0008] According to embodiments of the present disclosure for achieving the above object, a method of a user equipment (UE) includes: performing DL (downlink) communication with a first transmission and reception point (TRP); determining a first UL (uplink) transmission power for a first UL (uplink) communication with the first TRP based on a state of a DL channel between the UE and the first TRP; performing the first UL communication with the first TRP using the first UL transmission power; determining a second UL transmission power for a second UL communication with a second TRP based on a state and a power offset of the DL channel between the UE and the first TRP; and performing the second UL communication with the second TRP using the second UL transmission power.

[0009] The step of determining the second UL transmission power may include: measuring the quality of the DL channel based on a reference signal received on the DL channel; confirming a quality range to which the measured quality belongs; and confirming the power offset mapped to the quality range.

[0010] The method of the UE may further include a step of receiving mapping information between one or more quality ranges and one or more power offsets, wherein the quality range and the power offset can be identified based on the mapping information.

[0011] The above mapping information can be received via RRC (radio resource control) signaling of the first TRP.

[0012] The above measured quality may be RSRP (reference signal received power), and the above quality range may be RSRP range or RSRP threshold.

[0013] The second UL transmission power may be the sum of the first UL transmission power and the power offset.

[0014] The step of determining the second UL transmission power may include the step of determining a correction factor for path loss for the DL channel based on the power offset; and the step of determining the second UL transmission power based on the path loss to which the correction factor is reflected.

[0015] The method of the UE may further include a step of receiving, from the first TRP, a medium access control (MAC) control element (CE) or downlink control information (DCI) including a correction factor corresponding to the power offset, and the second UL transmission power may be determined based on a path loss in which the correction factor is reflected.

[0016] The method of the UE may further include the step of receiving RRC signaling including a plurality of correction factors from the first TRP, wherein the correction factor indicated by the MAC CE or the DCI may be one of the plurality of correction factors indicated by the RRC signaling.

[0017] The method of the UE may further include a step of receiving, from the first TRP, information indicating that the UL transmission power is applied differently for each TRP, and when the UL transmission power is indicated to be applied differently for each TRP, the first UL transmission power and the second UL transmission power may be independently determined.

[0018] According to embodiments of the present disclosure for achieving the above object, a user equipment (UE) includes at least one processor, wherein the at least one processor can cause the UE to perform downlink (DL) communication with a first transmission and reception point (TRP); determine a first uplink (UL) transmission power for a first UL communication with the first TRP based on a state of a DL channel between the UE and the first TRP; perform the first UL communication with the first TRP using the first UL transmission power; determine a second UL transmission power for a second UL communication with a second TRP based on a state and a power offset of the DL channel between the UE and the first TRP; and perform the second UL communication with the second TRP using the second UL transmission power.

[0019] In the step of determining the second UL transmission power, the at least one processor may cause the UE to measure the quality of the DL channel based on a reference signal received on the DL channel; identify a quality range to which the measured quality belongs; and identify the power offset mapped to the quality range.

[0020] The at least one processor may further cause the UE to receive mapping information between one or more quality ranges and one or more power offsets, wherein the quality range and the power offset may be identified based on the mapping information.

[0021] The above mapping information can be received via RRC (radio resource control) signaling of the first TRP.

[0022] The above measured quality may be RSRP (reference signal received power), and the above quality range may be RSRP range or RSRP threshold.

[0023] The second UL transmission power may be the sum of the first UL transmission power and the power offset.

[0024] In the step of determining the second UL transmission power, the at least one processor may cause the UE to determine a correction factor for path loss for the DL channel based on the power offset; and to determine the second UL transmission power based on the path loss to which the correction factor is reflected.

[0025] The at least one processor may further cause the UE to receive, from the first TRP, a medium access control (MAC) control element (CE) or downlink control information (DCI) including a correction factor corresponding to the power offset, and the second UL transmission power may be determined based on a path loss to which the correction factor is reflected.

[0026] The at least one processor may further cause the UE to receive RRC signaling from the first TRP, wherein the correction factor indicated by the MAC CE or the DCI may be one of the plurality of correction factors indicated by the RRC signaling.

[0027] The at least one processor may further cause the UE to receive information from the first TRP indicating that the UL transmission power is to be applied differently for each TRP, and when the UL transmission power is indicated to be applied differently for each TRP, the first UL transmission power and the second UL transmission power may be independently determined.

[0028] According to the present disclosure, in an asymmetric transmission and reception point (TRP) system, a terminal can perform downlink (DL) communication with a single TRP (sTRP), and the terminal can perform uplink (UL) communication with a multiple TRP (mTRP). In UL communication for the mTRP, the terminal can determine UL transmission power by applying different correction factors (e.g., different power offsets) according to path loss to the mTRP, and can perform UL communication with the mTRP using the UL transmission power. In other words, the first UL transmission power for the first TRP and the second UL transmission power for the second TRP can be independently determined. Therefore, the efficiency of power consumption in the terminal can be improved, and interference for UL communication can be efficiently controlled.

[0029] Figure 1 is a conceptual diagram illustrating embodiments of a communication system.

[0030] Figure 2 is a block diagram illustrating embodiments of communication nodes constituting a communication system.

[0031] Figure 3 is a block diagram illustrating embodiments of communication nodes that perform communication.

[0032] Figure 4a is a block diagram illustrating embodiments of a transmission path.

[0033] Figure 4b is a block diagram illustrating embodiments of a receiving path.

[0034] Figure 5 is a conceptual diagram illustrating embodiments of system frames in a communication system.

[0035] Figure 6 is a conceptual diagram illustrating embodiments of subframes in a communication system.

[0036] Figure 7 is a conceptual diagram illustrating embodiments of slots in a communication system.

[0037] Figure 8 is a conceptual diagram illustrating embodiments of time-frequency resources in a communication system.

[0038] Figure 9 is a conceptual diagram illustrating an embodiment of an asymmetric TRP system.

[0039] This disclosure may be subject to various modifications and various embodiments. Specific embodiments are illustrated and described in detail in the drawings. However, this is not intended to limit the disclosure to specific embodiments, but rather to encompass all modifications, equivalents, and alternatives falling within the spirit and technical scope of the disclosure.

[0040] While terms such as "first" and "second" may be used to describe various components, these components should not be limited by these terms. These terms are used solely to distinguish one component from another. For example, without departing from the scope of the present disclosure, a first component could be referred to as a "second component," and similarly, a second component could also be referred to as a "first component." The term "and / or" may refer to a combination of multiple related items described herein or to any of multiple related items described herein.

[0041] In the present disclosure, “at least one of A and B” may mean “at least one of A or B” or “at least one of combinations of one or more of A and B.” Additionally, in the present disclosure, “at least one of A and B” may mean “at least one of A or B” or “at least one of combinations of one or more of A and B.”

[0042] In the present disclosure, (re)transmission may mean “transmission,” “retransmission,” or “transmission and retransmission,” (re)setting may mean “setting,” “resetting,” or “setting and resetting,” (re)connection may mean “connection,” “reconnection,” or “connection and reconnection,” and (re)connection may mean “connection,” “reconnection,” or “connection and reconnection.”

[0043] When a component is referred to as being "connected" or "connected" to another component, it should be understood that it may be directly connected or connected to that other component, but that there may be other components intervening. Conversely, when a component is referred to as being "directly connected" or "connected" to another component, it should be understood that there are no other components intervening.

[0044] The terminology used in this disclosure is only used to describe specific embodiments and is not intended to limit the present disclosure. The singular expression includes the plural expression unless the context clearly indicates otherwise. In this disclosure, it should be understood that the terms "comprises" or "has" indicate the presence of a feature, number, step, operation, component, part, or combination thereof described in the specification, but do not preclude the presence or addition of one or more other features, numbers, steps, operations, components, parts, or combinations thereof.

[0045] Unless otherwise defined, all terms used herein, including technical or scientific terms, have the same meaning as commonly understood by a person of ordinary skill in the art to which this disclosure pertains. Terms defined in commonly used dictionaries should be interpreted as having a meaning consistent with their meaning in the context of the relevant technology, and shall not be interpreted in an idealized or overly formal sense unless explicitly defined herein.

[0046] 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 in describing the present disclosure, the same reference numerals will be used for identical components in the drawings, and redundant descriptions of identical components will be omitted. In addition to the embodiments explicitly described in the present disclosure, operations may be performed according to combinations of embodiments, extensions of embodiments, and / or modifications of embodiments. The performance of some operations may be omitted, and the order of operation may be changed.

[0047] In an embodiment, even if a method (e.g., transmitting or receiving a signal) performed by a first communication node among communication nodes is described, a corresponding second communication node can perform a method (e.g., receiving or transmitting a signal) corresponding to the method performed by the first communication node. That is, if an operation of a UE (user equipment) is described, a corresponding base station can perform an operation corresponding to the operation of the UE. Conversely, if an operation of a base station is described, a corresponding UE can perform an operation corresponding to the operation of the base station.

[0048] A base station may be referred to as a NodeB, an evolved NodeB, a gNodeB (next generation node B), a gNB, a device, an apparatus, a node, a communication node, a BTS (base transceiver station), a RRH (radio remote head), a TRP (transmission reception point), a RU (radio unit), an RSU (road side unit), a radio transceiver, an access point, an access node, etc. A UE may be referred to as a terminal, a device, an apparatus, a node, a communication node, an end node, an access terminal, a mobile terminal, a station, a subscriber station, a mobile station, a portable subscriber station, an OBU (on-broad unit), etc.

[0049] In the present disclosure, signaling may be at least one of upper layer signaling, MAC signaling, or PHY (physical) signaling. A message used for upper layer signaling may be referred to as an "upper layer message" or an "upper layer signaling message." A message used for MAC signaling may be referred to as a "MAC message" or a "MAC signaling message." A message used for PHY signaling may be referred to as a "PHY message" or a "PHY signaling message." Upper layer signaling may refer to a transmission and reception operation of system information (e.g., a master information block (MIB), a system information block (SIB)) and / or a radio resource control (RRC) message. MAC signaling may refer to a transmission and reception operation of a MAC control element (CE). PHY signaling may refer to a transmission and reception operation of control information (e.g., downlink control information (DCI), uplink control information (UCI), sidelink control information (SCI)).

[0050] In the present disclosure, “an operation (e.g., a transmission operation) is set” may mean that “setting information for the operation (e.g., an information element, a parameter)” and / or “information instructing the performance of the operation” is signaled. “An information element (e.g., a parameter) is set” may mean that the information element is signaled. In the present disclosure, “a signal and / or a channel” may mean a signal, a channel, or “a signal and a channel,” and a signal may be used to mean “a signal and / or a channel.”

[0051] The communication networks to which the embodiments are applied are not limited to those described below, and the embodiments may be applied to various communication networks (e.g., 4G communication networks, 5G communication networks, and / or 6G communication networks). Here, the term "communication network" may be used interchangeably with the term "communication system."

[0052] Figure 1 is a conceptual diagram illustrating embodiments of a communication system.

[0053] Referring to FIG. 1, the communication system (100) may include a plurality of communication nodes (110-1, 110-2, 110-3, 120-1, 120-2, 130-1, 130-2, 130-3, 130-4, 130-5, 130-6). In addition, the communication system (100) may further include a core network (e.g., a serving-gateway (S-GW), a packet data network (PDN)-gateway (P-GW), a mobility management entity (MME)). If the communication system (100) is a 5G communication system (e.g., a new radio (NR) system), the core network may include an access and mobility management function (AMF), a user plane function (UPF), a session management function (SMF), etc.

[0054] A plurality of communication nodes (110 to 130) can support a communication protocol specified in the 3rd generation partnership project (3GPP) standard (e.g., LTE communication protocol, LTE-A communication protocol, NR communication protocol, etc.). The plurality of communication nodes (110 to 130) may support CDMA (code division multiple access) technology, WCDMA (wideband CDMA) technology, TDMA (time division multiple access) technology, FDMA (frequency division multiple access) technology, OFDM (orthogonal frequency division multiplexing) technology, Filtered OFDM technology, CP (cyclic prefix)-OFDM technology, DFT-s-OFDM (discrete Fourier transform-spread-OFDM) technology, OFDMA (orthogonal frequency division multiple access) technology, SC (single carrier)-FDMA technology, NOMA (non-orthogonal multiple access) technology, GFDM (generalized frequency division multiplexing) technology, FBMC (filter bank multi-carrier) technology, UFMC (universal filtered multi-carrier) technology, SDMA (space division multiple access) technology, etc. Each of the plurality of communication nodes may have the following structure.

[0055] Figure 2 is a block diagram illustrating embodiments of communication nodes constituting a communication system.

[0056] Referring to FIG. 2, a communication node (200) may include at least one processor (210), a memory (220), and a transmission / reception device (230) that is connected to a network and performs communication. In addition, the communication node (200) may further include an input interface device (240), an output interface device (250), a storage device (260), etc. Each component included in the communication node (200) may be connected by a bus (270) and communicate with each other.

[0057] The processor (210) can execute program commands stored in at least one of the memory (220) and the storage device (260). The processor (210) may refer to a central processing unit (CPU), a graphics processing unit (GPU), or a dedicated processor in which the methods according to embodiments of the present disclosure are performed. Each of the memory (220) and the storage device (260) may be configured with at least one of a volatile storage medium and a non-volatile storage medium. For example, the memory (220) may be configured with at least one of a read-only memory (ROM) and a random access memory (RAM).

[0058] Referring again to FIG. 1, the communication system (100) may include a plurality of base stations (110-1, 110-2, 110-3, 120-1, 120-2) and a plurality of terminals (130-1, 130-2, 130-3, 130-4, 130-5, 130-6). Each of the first base station (110-1), the second base station (110-2), and the third base station (110-3) may form a macro cell. Each of the fourth base station (120-1) and the fifth base station (120-2) may form a small cell. The fourth base station (120-1), the third terminal (130-3), and the fourth terminal (130-4) may be within the cell coverage of the first base station (110-1). The second terminal (130-2), the fourth terminal (130-4), and the fifth terminal (130-5) may be within the cell coverage of the second base station (110-2). The fifth base station (120-2), the fourth terminal (130-4), the fifth terminal (130-5), and the sixth terminal (130-6) may be within the cell coverage of the third base station (110-3). The first terminal (130-1) may be within the cell coverage of the fourth base station (120-1). The sixth terminal (130-6) may be within the cell coverage of the fifth base station (120-2).

[0059] Here, each of the plurality of base stations (110-1, 110-2, 110-3, 120-1, 120-2) may be referred to as a NodeB (NB), an evolved NodeB (eNB), a gNB, an advanced base station (ABS), a high reliability-base station (HR-BS), a base transceiver station (BTS), a radio base station, a radio transceiver, an access point, an access node, a radio access station (RAS), a mobile multihop relay-base station (MMR-BS), a relay station (RS), an advanced relay station (ARS), a high reliability-relay station (HR-RS), a home NodeB (HNB), a home eNodeB (HeNB), a road side unit (RSU), a radio remote head (RRH), a transmission point (TP), a transmission and reception point (TRP), etc.

[0060] Each of the plurality of terminals (130-1, 130-2, 130-3, 130-4, 130-5, 130-6) may be referred to as a user equipment (UE), terminal equipment (TE), advanced mobile station (AMS), high reliability-mobile station (HR-MS), terminal, access terminal, mobile terminal, station, subscriber station, mobile station, portable subscriber station, node, device, on board unit (OBU), etc.

[0061] Meanwhile, each of the plurality of base stations (110-1, 110-2, 110-3, 120-1, 120-2) may operate in a different frequency band or may operate in the same frequency band. Each of the plurality of base stations (110-1, 110-2, 110-3, 120-1, 120-2) may be connected to each other via an ideal backhaul link or a non-ideal backhaul link, and may exchange information with each other via the ideal backhaul link or the non-ideal backhaul link. Each of the plurality of base stations (110-1, 110-2, 110-3, 120-1, 120-2) may be connected to the core network via the ideal backhaul link or the non-ideal backhaul link. Each of the plurality of base stations (110-1, 110-2, 110-3, 120-1, 120-2) 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.

[0062] Additionally, each of the plurality of base stations (110-1, 110-2, 110-3, 120-1, 120-2) may support MIMO transmission (e.g., single user (SU)-MIMO, multi user (MU)-MIMO, massive MIMO, etc.), coordinated multipoint (CoMP) transmission, carrier aggregation (CA) transmission, transmission in an unlicensed band, sidelink communication (e.g., device to device communication (D2D), proximity services (ProSe)), Internet of Things (IoT) communication, dual connectivity (DC), etc. Here, each of the plurality of terminals (130-1, 130-2, 130-3, 130-4, 130-5, 130-6) can perform an operation corresponding to the base station (110-1, 110-2, 110-3, 120-1, 120-2) and an operation supported by the base station (110-1, 110-2, 110-3, 120-1, 120-2). For example, the second base station (110-2) can transmit a signal to the fourth terminal (130-4) based on the SU-MIMO scheme, and the fourth terminal (130-4) can receive a signal from the second base station (110-2) by the SU-MIMO scheme. Alternatively, the second base station (110-2) can transmit signals to the fourth terminal (130-4) and the fifth terminal (130-5) based on the MU-MIMO method, and each of the fourth terminal (130-4) and the fifth terminal (130-5) can receive signals from the second base station (110-2) based on the MU-MIMO method.

[0063] Each of the first base station (110-1), the second base station (110-2), and the third base station (110-3) can transmit a signal to the fourth terminal (130-4) based on the CoMP scheme, and the fourth terminal (130-4) can receive a signal from the first base station (110-1), the second base station (110-2), and the third base station (110-3) based on the CoMP scheme. Each of the plurality of base stations (110-1, 110-2, 110-3, 120-1, 120-2) can transmit and receive a signal with terminals (130-1, 130-2, 130-3, 130-4, 130-5, 130-6) within its cell coverage based on the CA scheme. Each of the first base station (110-1), the second base station (110-2), and the third base station (110-3) can control sidelink communication between the fourth terminal (130-4) and the fifth terminal (130-5), and each of the fourth terminal (130-4) and the fifth terminal (130-5) can perform sidelink communication under the control of the second base station (110-2) and the third base station (110-3), respectively.

[0064] Meanwhile, communication nodes performing communication in a communication network may be configured as follows. The communication node illustrated in Fig. 3 may be a specific embodiment of the communication node illustrated in Fig. 2.

[0065] Figure 3 is a block diagram illustrating embodiments of communication nodes that perform communication.

[0066] Referring to FIG. 3, each of the first communication node (300a) and the second communication node (300b) may be a base station or a UE. The first communication node (300a) may transmit a signal to the second communication node (300b). The transmission processor (311) included in the first communication node (300a) may receive data (e.g., a data unit) from a data source (310). The transmission processor (311) may receive control information from the controller (316). The control information may include at least one of system information, RRC configuration information (e.g., information configured by RRC signaling), MAC control information (e.g., MAC CE), or PHY control information (e.g., DCI, SCI).

[0067] The transmitting processor (311) may perform a processing operation on data (e.g., an encoding operation, a symbol mapping operation, etc.) to generate data symbol(s). The transmitting processor (311) may perform a processing operation on control information (e.g., an encoding operation, a symbol mapping operation, etc.) to generate control symbol(s). In addition, the transmitting processor (311) may generate synchronization / reference symbol(s) for a synchronization signal and / or a reference signal.

[0068] The Tx MIMO processor (312) may perform a spatial processing operation (e.g., a precoding operation) on data symbol(s), control symbol(s), and / or synchronization / reference symbol(s). The output (e.g., a symbol stream) of the Tx MIMO processor (312) may be provided to modulators (MODs) included in the transceivers (313a to 313t). The modulators (MODs) may perform a processing operation on the symbol stream to generate modulation symbols, and may perform an additional processing operation (e.g., an analog conversion operation, an amplification operation, a filtering operation, an upconversion operation) on the modulation symbols to generate signals. The signals generated by the modulators (MODs) of the transceivers (313a to 313t) may be transmitted via the antennas (314a to 314t).

[0069] Signals transmitted by the first communication node (300a) may be received by antennas (364a to 364r) of the second communication node (300b). Signals received by the antennas (364a to 364r) may be provided to demodulators (DEMODs) included in transceivers (363a to 363r). The demodulator (DEMOD) may perform a processing operation (e.g., a filtering operation, an amplification operation, a downconversion operation, a digital conversion operation) on the signal to obtain samples. The demodulator (DEMOD) may perform an additional processing operation on the samples to obtain symbols. The MIMO detector (362) may perform a MIMO detection operation on the symbols. The receiving processor (361) may perform a processing operation (e.g., a deinterleaving operation, a decoding operation) on the symbols. The output of the receiving processor (361) may be provided to a data sink (360) and a controller (366). For example, data may be provided to the data sink (360), and control information may be provided to the controller (366).

[0070] Meanwhile, the second communication node (300b) can transmit a signal to the first communication node (300a). The transmitting processor (368) included in the second communication node (300b) can receive data (e.g., data units) from a data source (367) and perform a processing operation on the data to generate data symbol(s). The transmitting processor (368) can receive control information from the controller (366) and perform a processing operation on the control information to generate control symbol(s). In addition, the transmitting processor (368) can perform a processing operation on a reference signal to generate reference symbol(s).

[0071] The Tx MIMO processor (369) may perform spatial processing operations (e.g., precoding operations) on data symbol(s), control symbol(s), and / or reference symbol(s). The output (e.g., symbol stream) of the Tx MIMO processor (369) may be provided to modulators (MODs) included in the transceivers (363a to 363t). The modulators (MODs) may perform processing operations on the symbol streams to generate modulation symbols, and may perform additional processing operations (e.g., analog conversion operations, amplification operations, filtering operations, upconversion operations) on the modulation symbols to generate signals. The signals generated by the modulators (MODs) of the transceivers (363a to 363t) may be transmitted via the antennas (364a to 364t).

[0072] Signals transmitted by the second communication node (300b) may be received by the antennas (314a to 314r) of the first communication node (300a). The signals received by the antennas (314a to 314r) may be provided to demodulators (DEMODs) included in the transceivers (313a to 313r). The demodulator (DEMOD) may perform a processing operation (e.g., a filtering operation, an amplification operation, a downconversion operation, a digital conversion operation) on the signal to obtain samples. The demodulator (DEMOD) may perform an additional processing operation on the samples to obtain symbols. The MIMO detector (320) may perform a MIMO detection operation on the symbols. The receiving processor (319) may perform a processing operation (e.g., a deinterleaving operation, a decoding operation) on the symbols. The output of the receiving processor (319) may be provided to a data sink (318) and a controller (316). For example, data may be provided to the data sink (318) and control information may be provided to the controller (316).

[0073] Memories (315 and 365) can store data, control information, and / or program code. Scheduler (317) can perform scheduling operations for communication. The processors (311, 312, 319, 361, 368, 369) and controllers (316, 366) illustrated in FIG. 3 may be the processor (210) illustrated in FIG. 2 and may be used to perform the methods described in the present disclosure.

[0074] FIG. 4a is a block diagram illustrating embodiments of a transmission path, and FIG. 4b is a block diagram illustrating embodiments of a reception path.

[0075] Referring to FIGS. 4A and 4B, a transmission path (410) may be implemented in a communication node that transmits a signal, and a reception path (420) may be implemented in a communication node that receives a signal. The transmission path (410) may include a channel coding and modulation block (411), an S-to-P (serial-to-parallel) block (512), an N IFFT (Inverse Fast Fourier Transform) block (413), a P-to-S (parallel-to-serial) block (414), a CP (cyclic prefix) addition block (415), and an UC (up-converter) (UC) (416). The receiving path (420) may include a DC (down-converter) (421), a CP removal block (422), an S-to-P block (423), an N FFT block (424), a P-to-S block (425), and a channel decoding and demodulation block (426). Here, N may be a natural number.

[0076] In the transmission path (410), information bits may be input to a channel coding and modulation block (411). The channel coding and modulation block (411) may perform a coding operation (e.g., a low-density parity check (LDPC) coding operation, a polar coding operation, etc.) and a modulation operation (e.g., a quadrature phase shift keying (QPSK), a quadrature amplitude modulation (QAM), etc.) on the information bits. The output of the channel coding and modulation block (411) may be a sequence of modulation symbols.

[0077] The S-to-P block (412) can convert modulation symbols in the frequency domain into parallel symbol streams to generate N parallel symbol streams. N can be an IFFT size or an FFT size. The N IFFT block (413) can perform an IFFT operation on the N parallel symbol streams to generate signals in the time domain. The P-to-S block (414) can convert the output (e.g., parallel signals) of the N IFFT block (413) into a serial signal to generate a serial signal.

[0078] The CP addition block (415) can insert a CP into a signal. The UC (416) can up-convert the frequency of the output of the CP addition block (415) to an RF (radio frequency) frequency. Additionally, the output of the CP addition block (415) can be filtered at the baseband before up-conversion.

[0079] A signal transmitted from a transmission path (410) may be input to a reception path (420). An operation in the reception path (420) may be the reverse operation of the operation in the transmission path (410). A DC (421) may down-convert the frequency of the received signal to a baseband frequency. A CP removal block (422) may remove a CP from a signal. The output of the CP removal block (422) may be a serial signal. An S-to-P block (423) may convert the serial signal into parallel signals. An N FFT block (424) may perform an FFT algorithm to generate N parallel signals. A P-to-S block (425) may convert the parallel signals into a sequence of modulation symbols. A channel decoding and demodulation block (426) may perform a demodulation operation on the modulation symbols and perform a decoding operation on the result of the demodulation operation to restore data.

[0080] In FIGS. 4A and 4B , Discrete Fourier Transform (DFT) and Inverse DFT (IDFT) may be used instead of FFT and IFFT. Each of the blocks (e.g., components) in FIGS. 4A and 4B may be implemented by at least one of hardware, software, or firmware. For example, some of the blocks in FIGS. 4A and 4B may be implemented by software, and the remaining blocks may be implemented by hardware or a “combination of hardware and software.” In FIGS. 4A and 4B , a block may be subdivided into multiple blocks, multiple blocks may be integrated into a single block, some blocks may be omitted, and blocks supporting other functions may be added.

[0081] Figure 5 is a conceptual diagram illustrating embodiments of a system frame in a communication system.

[0082] Referring to FIG. 5, time resources in a communication system can be divided into frame units. For example, system frames can be set consecutively in the time domain of the communication system. The length of a system frame can be 10 ms (milliseconds). The system frame number (SFN) can be set from #0 to #1023. In this case, 1024 system frames can be repeated in the time domain of the communication system. For example, the SFN of the system frame after system frame #1023 can be #0.

[0083] A system frame may include two half frames. A half frame may be 5 ms long. A half frame located at the beginning of the system frame may be referred to as "half frame #0," and a half frame located at the end of the system frame may be referred to as "half frame #1." A system frame may include 10 subframes. A subframe may be 1 ms long. The 10 subframes within a system frame may be referred to as "subframes #0-9."

[0084] Figure 6 is a conceptual diagram illustrating embodiments of subframes in a communication system.

[0085] Referring to FIG. 6, one subframe may include n slots, where n may be a natural number. Accordingly, one subframe may be composed of one or more slots.

[0086] Figure 7 is a conceptual diagram illustrating embodiments of slots in a communication system.

[0087] Referring to FIG. 7, a single slot may include one or more symbols. A single slot illustrated in FIG. 7 may include 14 symbols. The length of a slot may vary depending on the number and length of symbols contained in the slot. Alternatively, the length of a slot may vary depending on the numerology.

[0088] In a communication system, the numerology applied to physical signals and channels may be variable. The numerology may be variable to meet various technical requirements of the communication system. In a communication system applying CP (cyclic prefix)-based OFDM waveform technology, the numerology may include subcarrier spacing and CP length (or CP type). Table 1 may be a first embodiment of a method for configuring a numerology for a CP-OFDM-based communication system. At least some of the numerologies in Table 1 may be supported depending on the frequency band in which the communication system operates. In addition, the communication system may additionally support numerologies not listed in Table 1.

[0089]

[0090] When the subcarrier spacing is 15 kHz (e.g., μ=0), the slot length can be 1 ms. In this case, one system frame can contain 10 slots. When the subcarrier spacing is 30 kHz (e.g., μ=1), the slot length can be 0.5 ms. In this case, one system frame can contain 20 slots.

[0091] When the subcarrier spacing is 60 kHz (e.g., μ=2), the slot length can be 0.25 ms. In this case, one system frame can contain 40 slots. When the subcarrier spacing is 120 kHz (e.g., μ=3), the slot length can be 0.125 ms. In this case, one system frame can contain 80 slots. When the subcarrier spacing is 240 kHz (e.g., μ=4), the slot length can be 0.0625 ms. In this case, one system frame can contain 160 slots.

[0092] A symbol may be configured as a downlink (DL) symbol, a flexible (FL) symbol, or an uplink (UL) symbol. A slot consisting solely of DL symbols may be referred to as a "DL slot," a slot consisting solely of FL symbols may be referred to as an "FL slot," and a slot consisting solely of UL symbols may be referred to as a "UL slot."

[0093] The slot format can be semi-statically configured by higher layer signaling (e.g., RRC signaling). Information indicating the semi-static slot format can be included in the system information, and the semi-static slot format can be configured cell-specifically. In addition, the semi-static slot format can be additionally configured for each terminal through terminal-specific higher layer signaling (e.g., RRC signaling). The flexible symbol of the cell-specifically configured slot format can be overridden to a downlink symbol or an uplink symbol by terminal-specific higher layer signaling. In addition, the slot format can be dynamically indicated by physical layer signaling (e.g., a slot format indicator (SFI) included in DCI). The semi-statically configured slot format can be overridden by a dynamically indicated slot format. For example, the semi-statically configured flexible symbol can be overridden to a downlink symbol or an uplink symbol by the SFI.

[0094] The reference signal may be a channel state information-reference signal (CSI-RS), a sounding reference signal (SRS), a demodulation-reference signal (DM-RS), a phase tracking-reference signal (PT-RS), etc. The channel may be a physical broadcast channel (PBCH), a physical downlink control channel (PDCCH), a physical downlink shared channel (PDSCH), a physical uplink control channel (PUCCH), a physical uplink shared channel (PUSCH), a physical sidelink control channel (PSCCH), a physical sidelink shared channel (PSSCH), etc. In the present disclosure, a control channel may mean a PDCCH, a PUCCH, or a PSCCH, and a data channel may mean a PDSCH, a PUSCH, or a PSSCH.

[0095] Figure 8 is a conceptual diagram illustrating embodiments of time-frequency resources in a communication system.

[0096] Referring to FIG. 8, a resource consisting of one symbol (e.g., an OFDM symbol) in the time domain and one subcarrier in the frequency domain may be defined as a "RE (resource element)". Resources consisting of one OFDM symbol in the time domain and K subcarriers in the frequency domain may be defined as a "REG (resource element group)". A REG may include K REs. A REG may be used as a basic unit for resource allocation in the frequency domain. K may be a natural number. For example, K may be 12. N may be a natural number. In the slot illustrated in FIG. 7, N may be 14. N OFDM symbols may be used as a basic unit for resource allocation in the time domain.

[0097] In the present disclosure, RB may mean CRB (common RB). Alternatively, RB may mean PRB or VRB (virtual RB). In a communication system, CRB may mean RB that constitutes a set of consecutive RBs (e.g., a common RB grid) based on a reference frequency (e.g., point A). Carriers and / or bandwidth portions may be arranged on the common RB grid. That is, the carrier and / or bandwidth portions may be composed of CRB(s). RBs or CRBs that constitute the bandwidth portions may be referred to as PRBs, and within the bandwidth portions, the CRB index may be appropriately converted to the PRB index.

[0098] Downlink data can be transmitted via the PDSCH. The base station can transmit PDSCH configuration information (e.g., scheduling information) to the terminal via the PDCCH. The terminal can obtain the PDSCH configuration information by receiving the PDCCH (e.g., downlink control information (DCI)). For example, the PDSCH configuration information can include the MCS (modulation coding scheme) used for transmitting and receiving the PDSCH, time resource information of the PDSCH, frequency resource information of the PDSCH, feedback resource information for the PDSCH, etc. The PDSCH can refer to a radio resource through which downlink data is transmitted and received. Alternatively, the PDSCH can refer to the downlink data itself. The PDCCH can refer to a radio resource through which downlink control information (e.g., DCI) is transmitted and received. Alternatively, the PDCCH can refer to the downlink control information itself.

[0099] A terminal can perform a monitoring operation on the PDCCH to receive a PDSCH transmitted from a base station. The base station can inform the terminal of the configuration information for the PDCCH monitoring operation using a higher layer message (e.g., an RRC (radio resource control) message). The configuration information for the PDCCH monitoring operation can include CORESET (control resource set) information and search space information.

[0100] CORESET information may include PDCCH DMRS (demodulation reference signal) information, PDCCH precoding information, PDCCH occasion information, etc. The PDCCH DMRS may be a DMRS used to demodulate the PDCCH. The PDCCH occasion may be a region where the PDCCH can exist. That is, the PDCCH occasion may be a region where DCI can be transmitted. The PDCCH occasion may be referred to as a PDCCH candidate. The PDCCH occasion information may include time resource information and frequency resource information of the PDCCH occasion. In the time domain, the length of the PDCCH occasion may be indicated in symbol units. In the frequency domain, the size of the PDCCH occasion may be indicated in RB units (e.g., in PRB (physical resource block) units or CRB (common resource block) units).

[0101] The search space information may include a coreset identifier (ID) associated with the search space, a period of PDCCH monitoring, and / or an offset. Each of the PDCCH monitoring period and offset may be indicated on a slot-by-slot basis. In addition, the search space information may further include an index of the symbol at which the PDCCH monitoring operation begins.

[0102] A base station can configure a bandwidth part (BWP) for downlink communication. The BWP can be configured differently for each terminal. The base station can inform the terminal of the BWP configuration information using higher layer signaling. The higher layer signaling can mean "transmission operation of system information" and / or "transmission operation of RRC (radio resource control) message." The number of BWPs configured for one terminal can be one or more. The terminal can receive BWP configuration information from the base station and check the BWP(s) configured by the base station based on the BWP configuration information. When multiple BWPs are configured for downlink communication, the base station can activate one or more BWPs among the multiple BWPs. The base station can transmit the configuration information of the activated BWP(s) to the terminal using at least one of higher layer signaling, a medium access control (MAC) control element (CE), or DCI. The base station can perform downlink communication using the activated BWP(s). The terminal can identify the activated BWP(s) by receiving configuration information of the activated BWP(s) from the base station, and perform a downlink reception operation in the activated BWP(s).

[0103] Meanwhile, a communication system (e.g., NR communication system, 5G communication system, 6G communication system) may support usage scenarios such as enhanced Mobile BroadBand (eMBB), Ultra Reliable Low Latency Communication (URLLC), and massive Machine Type Communication (mMTC). A communication system (e.g., a communication network) may support transmission and reception point (TRP) technology (e.g., multiple TRP (mTRP) technology and / or single TRP (sTRP) technology). A communication system supporting the TRP technology may be referred to as a TRP system (e.g., mTRP system and / or sTRP system). In the present disclosure, TRP may have a meaning including sTRP and / or mTRP, and TRP may mean sTRP or mTRP depending on the context. TRP may mean an antenna set, an antenna group, and / or an antenna array. A TRP may be associated with a CORESET and / or a beam (e.g., a beam group).

[0104] mTRP technology may fall under the category of MIMO technology. mTRP may have characteristics (e.g., level characteristics) of macrocells, small cells, picocells, and / or femtocells. mTRP can perform data transmission for a single terminal. In a channel (e.g., a link) with uneven channel conditions due to obstacles and / or interference, mTRP can attenuate the effects of the obstacles and / or interference. mTRP can improve the data transmission rate for terminals located at cell edge areas.

[0105] mTRP-based communication can be performed using either coherent joint transmission (CJT) or non-CJT (NCJT) methods. In CJT, the base station can obtain channel information between each mTRP and the terminal and perform preprocessing on the data based on this channel information. In this case, the overhead associated with transmitting channel information may increase, and synchronization constraints between TRPs may arise. In NCJT, the base station may not need to know the channel information between each mTRP and the terminal. mTRPs can transmit data to the terminal without performing preprocessing operations such as phase compensation. The complexity of NCJT may be lower than that of CJT.

[0106] NCJT-based mTRP communication can be performed based on a single DCI scheme or a multiple DCI scheme. In the single DCI scheme, PDSCHs transmitted by an mTRP can be scheduled by a single DCI. A single DCI can be transmitted by one TRP among the mTRPs. In the multiple DCI scheme, the PDSCHs transmitted by each TRP can be scheduled by the DCI transmitted by each TRP. For example, a first PDSCH transmitted by a first TRP can be scheduled by a first DCI transmitted by the first TRP, and a second PDSCH transmitted by a second TRP can be scheduled by a second DCI transmitted by the second TRP. In other words, multiple PDSCHs can be scheduled using multiple DCIs.

[0107] In a single SCI scheme, a terminal can expect to receive PDSCHs transmitted by different TRPs over the same time and frequency resources and across different layers. Alternatively, the terminal can expect to receive PDSCHs transmitted by different TRPs over the same frequency resources and across the same layer but across different time resources (e.g., across different time domains). Alternatively, the terminal can expect to receive PDSCHs transmitted by different TRPs over the same time resources and across the same layer but across different frequency resources (e.g., across different frequency domains).

[0108] In a multi-DCI scheme, scheduling of PDSCHs for each TRP can be performed by a separate DCI. The PDSCHs scheduled by multiple DCIs may fully overlap or partially overlap. Alternatively, the PDSCHs scheduled by multiple DCIs may not overlap. In both single-DCI and multi-DCI schemes, the DCI may include transmission configuration indicator (TCI) status information for the PDSCH.

[0109] The indication / setting of the TCI state for the terminal can be interpreted as the indication / setting of a beam (e.g., a transmit beam and / or a receive beam). In other words, the TCI state can have a meaning corresponding to the beam. From the perspective of DL (downlink) communication, the setting of the TCI state can mean the setting of QCL (quasi co-location). From the perspective of UL (uplink) communication, the setting of the TCI state can mean the setting of a spatial filter. The unified TCI state can indicate (e.g., set) a common beam regardless of DL communication and UL communication. Alternatively, the unified TCI state can indicate (e.g., set) a common beam for each of DL communication and UL communication. The unified TCI can be referred to as UTCI.

[0110] Enhancements (e.g., PDCCH enhancements) may be implemented to improve the reliability and / or robustness of mTRP communications. Deployment scenarios for PDCCH enhancements can be categorized into single frequency network (SFN) and non-SFN scenarios.

[0111] In the SFN scheme, different TRPs or different panels can transmit the same PDCCH using the same resources (e.g., the same time resources, the same frequency resources, and / or the same spatial resources). In other words, all TRPs or all panels can transmit the same PDCCH using the same DMRS configuration, the same DMRS location, and / or the same DMRS sequence. At this time, the TCI states for the reception perspective of the TRPs or panels can be implicitly set differently. The above embodiment can be performed based on multiple TCI states of the CORESET. There may be synchronization constraints for ideal or near-ideal backhaul between TRPs.

[0112] In the NSFN scheme, the PDCCH generated from each TRP can be multiplexed in the time domain and / or frequency domain, and the multiplexed PDCCH can be transmitted to the terminal. The scheme may be an mTRP-based PDCCH repetition scheme. In the NSFN scheme, the same number of bits as the encoded bits transmitted through one PDCCH generated from each TRP can be divided for each TRP, and the bits (e.g., encoded bits) for each TRP can be transmitted through different PDCCH candidates. The scheme may be an sTRP-based PDCCH transmission scheme.

[0113] In the mTRP-based PDCCH repetition scheme, the PDCCH can be repeatedly generated as many times as the number of TRPs, and the PDCCH can be transmitted in the same search space (e.g., search spaces having the same index) within different search space sets having the same number of PDCCH candidates. At this time, the search space sets can exist within the same CORESET or different CORESETs. Since one TCI state can be associated with each CORESET, when the PDCCH is transmitted in different search spaces within the same CORESET, only one TCI state can be indicated (e.g., set) for the PDCCHs transmitted in the different search spaces. In this case, the UE can receive the PDCCH from one TRP at a specific time.

[0114] When a PDCCH is transmitted in the same search space within different CORESETs, the UE can implicitly expect to receive the PDCCH from either the sTRP or the mTRP, depending on the number of TCI states (e.g., TCI states indicated or configured by the base station). In this case, a single PDCCH can be split as many times as the number of TRPs, and the split PDCCHs can be transmitted on different PDCCH candidates. At this time, the aggregation level and the combined aggregation level can be the same. In the above embodiment, the PDCCH candidates can be assigned to different CORESETs. The payload size for the final distributed PDCCH combination can be the same as the payload size of the PDCCH transmitted in the sTRP. Therefore, in terms of decoding complexity, the sTRP-based PDCCH transmission scheme can be advantageous over the mTRP-based PDCCH repetition scheme.

[0115] A terminal can perform mTRP communication or sTRP communication with a base station. mTRP communication between the terminal and the base station can be performed through an mTRP associated with the base station. sTRP communication between the terminal and the base station can be performed through an sTRP associated with the base station. mTRP communication may be referred to as first TRP communication, and sTRP communication may be referred to as second TRP communication. Alternatively, mTRP communication may be referred to as second TRP communication, and sTRP communication may be referred to as first TRP communication. "The terminal performs first TRP communication with the base station" may mean "the terminal performs mTRP communication or sTRP communication with the base station through one or more TRPs associated with the base station." "The terminal performs second TRP communication with the base station" may mean "the terminal performs sTRP communication or mTRP communication with the base station through one or more TRPs associated with the base station."

[0116] In a communication system, integrated TCI can be supported. A base station can transmit information about a pool (e.g., a list) of TCI states to a terminal using RRC signaling. The terminal can receive information about a pool (e.g., a list) of TCI states through RRC signaling from the base station. The base station can set type information about the TCI state to the terminal. The type information can be a joint DL / UL beam indication or a separate DL / UL beam indication. A joint DL / UL beam indication can be referred to as a 'joint indication or joint type.' An independent DL / UL beam indication can be referred to as an 'independent indication or independent type.'

[0117] When a joint type (e.g., joint indication) is set, TCI states (e.g., one TCI state) for DL ​​and UL may be set. In other words, DL TCI state setting and UL TCI state setting may be the same. The UE may expect that the TCI state indicated by the information element included in the PDSCH configuration information applies to both DL (e.g., DL signal / channel) and UL (e.g., UL signal / channel). The signal / channel may refer to a signal and / or a channel. When an independent type (e.g., independent indication) is set, TCI states for DL ​​and UL may be set respectively. In other words, DL TCI state setting may be distinguished from UL TCI state setting. The UE may expect that the UL TCI state indicated by the information element included in the UL BWP configuration information applies to UL (e.g., UL signal / channel). The UL signal / channel may include a PUSCH, a PUCCH, and / or an SRS.

[0118] After the pool (e.g., pool list) for TCI states is configured (e.g., indicated) by RRC signaling, the base station can use DCI (e.g., DCI signaling) to indicate the TCI state (e.g., application of the TCI state). Due to the constraint of the DCI size (e.g., bits in the DCI field), the base station can preferentially activate candidate TCI state(s) using MAC signaling (e.g., MAC CE signaling). In other words, as many (e.g., maximum number) candidate TCI state(s) as can be indicated (e.g., configured) via DCI can be preferentially activated by MAC CE.

[0119] For the activated candidate TCI state(s), the DCI may contain code points corresponding to a single TCI state or two TCI states, depending on the TCI state type (e.g., joint type or independent type). If the joint type is set, the code points corresponding to a single TCI state may be conveyed by the DCI. If the independent type is set, the code points corresponding to two TCI states may be conveyed by the DCI.

[0120] Unified TCI extensions for multiple TRPs can be supported. Up to two TRPs can be supported. The base station can configure up to 128 TCI states for the TCI state pool via RRC configuration. The base station can activate up to 32 TCI states for eight codepoints using MAC CE. The base station can indicate up to four TCI states for two TRPs using DCI.

[0121] To check the DL channel status, a synchronization signal block (SSB) and / or a CSI-RS may be used. SSB may be transmitted periodically for time synchronization between the UE and the base station. SSB may be transmitted without a transmission request (e.g., a transmission request). Therefore, the transmission overhead of SSB may be smaller than that of CSI-RS. SSB may be transmitted within a specific frequency range. Due to limitations in the transmission frequency range, SSB may not be used to check the channel status for the frequency range that the UE wishes to measure and / or the frequency range supported by the entire system. In channel status measurement, SSB and CSI-RS may each have advantages and disadvantages. For measuring (e.g., checking) the DL channel status, either SSB or CSI-RS may be used depending on specific environments and / or specific conditions.

[0122] Channel state reports (e.g., CSI reports) can be categorized into three types. For example, channel state reports can be categorized into periodic channel state reports, semi-persistent channel state reports, and aperiodic channel state reports. In periodic channel state reports (e.g., periodic CSI reports), a terminal can transmit a channel state report to a base station according to a period set by the base station. In semi-static channel state reports (e.g., semi-static CSI reports), a terminal can transmit a channel state report to a base station during a certain period. In aperiodic channel state reports (e.g., aperiodic CSI reports), a terminal can transmit a channel state report to a base station according to a request from the base station (e.g., a CSI request). In other words, channel state reports can be transmitted intermittently.

[0123] A channel state report may include a precoding matrix indicator (PMI), a rank indicator (RI), a layer indicator (LI), a channel quality indicator (CQI), a CSI reference resource indicator (CRI), an SS / PBCH block resource indicator (SSBRI), a reference signal received power (RSRP), and / or a signal to interference plus noise ratio (SINR). A channel state report may include a capability index. A channel state report may include up to eight pieces of information. A CSI-RS may be used to measure a channel state. A base station may transmit an RRC message including resource information of the CSI-RS (e.g., CSI-ResourceConfig, CSI-Measconfig) to a terminal. The terminal may receive the RRC message from the base station and obtain the resource information of the CSI-RS included in the RRC message.

[0124] The resource information of the CSI-RS may include at least one of a time resource on which the CSI-RS is transmitted, a frequency resource on which the CSI-RS is transmitted, a transmission period of the CSI-RS, or a resource type of the CSI-RS (e.g., a periodic type, a semi-static type, or an aperiodic type). In addition, the RRC message may include configuration information for a CSI measurement report (e.g., CSI-ReportConfig). The type of the CSI-RS resource and the type of the CSI report (e.g., a CSI measurement report) may be configured independently. For example, when an aperiodic CSI report is required, the UE may perform measurement on all CSI-RS resources regardless of periodic CSI-RS resources, semi-static CSI-RS resources, and aperiodic CSI-RS resources, and transmit an aperiodic CSI report including the measurement result to the base station. For another example, if periodic CSI reporting is required, the terminal may perform measurements on periodic CSI-RS resources and transmit a periodic CSI report including the measurement results to the base station. For another example, if semi-static CSI reporting is required, the terminal may perform measurements on periodic CSI-RS resources and / or semi-static CSI-RS resources and transmit an aperiodic CSI report including the measurement results to the base station.

[0125] CSI-RS resource configuration can have a hierarchical structure. In other words, CSI-RS resources can be configured hierarchically. To indicate factors for obtaining minimal channel information, a set of REs with a specific pattern in the time and frequency domains can be referred to as a resource. Resource sets can be defined to indicate (e.g., configure) a set of resources at once. A separate ID can be assigned to distinguish each resource and resource set. Different resource sets can contain different resources, or different resource sets can contain the same resource(s). To flexibly utilize resources and resource sets, a group (e.g., a resource set list) containing resource sets can be configured, and the group can be defined based on resource configuration information (e.g., CSI-ResourceConfig). A specific ID can be configured for each set of resource sets (e.g., a resource set list).

[0126] A set of CSI-RS resources may be defined as a "CSI-RS resource set list" or "set list." In the present disclosure, periodic may be referred to as P, semi-persistent may be referred to as SP, and aperiodic may be referred to as AP. In other words, periodic CSI-RS, semi-persistent CSI-RS, and aperiodic CSI-RS may be referred to as P CSI-RS, SP CSI-RS, and AP CSI-RS, respectively, and periodic CSI reports, semi-persistent CSI reports, and aperiodic CSI reports may be referred to as P CSI reports, SP CSI reports, and AP CSI reports, respectively. CSI-RS resource(s) by type (e.g., P, SP, AP) may be set as a unit of a CSI-RS resource set list. CSI-RS resource set(s) and / or CSI-RS resource(s) belonging to the same CSI-RS resource set list can be interpreted as having the same type. Since the CSI-RS resource set list is configured by type, CSI reports can be requested or transmitted by CSI-RS resource set list. The resource configuration of CSI-RS can have a hierarchical structure in the order of CSI-RS resource → CSI-RS resource set → CSI-RS resource set list. One or more CSI-RS resources can belong to a CSI-RS resource set, and one or more CSI-RS resource sets can belong to a CSI-RS resource set list.

[0127] The configuration information of a CSI report may be transmitted to a terminal together with the configuration information of CSI-RS resources. Depending on the purpose of CSI measurement (e.g., channel measurement, interference measurement), configuration information (e.g., allocation information) for different CSI-RS resource set lists may be transmitted to the terminal. The configuration information of a CSI report may include all information necessary for a terminal to transmit a CSI report. For example, the configuration information of a CSI report may include at least one of a CSI report type (e.g., P, SP, AP), a time resource for which CSI measurement is required, a frequency resource for which CSI measurement is required, or a type of information included in the CSI report. The channel through which the CSI report is transmitted may vary depending on the size of the CSI report. For example, a P CSI report may be transmitted via a PUCCH. An SP CSI report may be transmitted via a PUCCH or a PUSCH. An AP CSI report may be transmitted via a PUSCH. The size of an AP CSI report may be larger than the size of an SP CSI report, and the size of an SP CSI report may be larger than the size of a P CSI report.

[0128] The type-specific CSI reporting procedure can be performed as follows. The base station can transmit an RRC message including configuration information for CSI measurement, configuration information for CSI-RS resources, and / or configuration information for CSI reporting to the terminal. The terminal can obtain configuration information for CSI measurement, configuration information for CSI-RS resources, and / or configuration information for CSI reporting from the base station. In the P CSI reporting procedure, the terminal can measure a DL channel based on P CSI-RS without a separate triggering signal (e.g., a triggering signal), and transmit a CSI report including the measurement result to the base station according to a CSI reporting cycle configured by RRC signaling (e.g., an RRC message).

[0129] In the SP CSI reporting procedure, the base station may transmit information (e.g., MAC CE) indicating activation of SP CSI measurement / reporting to the terminal. When SP CSI measurement / reporting is activated, the terminal may measure a DL channel based on the P CSI-RS and transmit a CSI report including the measurement result to the base station according to a CSI reporting cycle set by RRC signaling (e.g., an RRC message). The transmission operation of the CSI report may be performed until information (e.g., MAC CE) indicating deactivation of SP CSI measurement / reporting is received from the base station. Activation signaling and / or deactivation signaling for SP CSI measurement / reporting may be required for the SP CSI reporting procedure. In the period between the activation signaling and the deactivation signaling, the terminal may measure a DL channel based on the SP CSI-RS and transmit a CSI report including the measurement result to the base station.

[0130] In the AP CSI reporting procedure, the base station can transmit a signaling message (e.g., DCI or MAC CE) to the terminal to trigger AP CSI measurement / reporting. The signaling message can indicate one CSI report. The terminal can receive the signaling message from the base station and confirm that AP CSI measurement / reporting is triggered based on the signaling message. The AP CSI-RS resource measured by the terminal can be an AP CSI-RS resource existing N slots after a slot in which a signaling message triggering AP CSI measurement / reporting is received, and the AP CSI report can be transmitted M slots after a slot in which a signaling message triggering AP CSI measurement / reporting is received. Each of N and M can be a natural number. Information about the N slots indicating the AP CSI-RS resource and / or information about the M slots indicating the timing of the AP CSI report can be transmitted to the terminal via RRC signaling. Information about N slots indicating AP CSI-RS resources and / or information about M slots indicating timing of AP CSI reporting may be transmitted to the terminal together with configuration information of CSI measurement, configuration information of CSI-RS resources, and / or configuration information of CSI reporting.

[0131] A terminal can individually perform data transmission using multiple panels. In other words, the terminal can independently perform data transmission using each of the multiple panels. The terminal can transmit information necessary for data transmission for each panel to the terminal. The base station can obtain information necessary for data transmission for each panel from the terminal. One of the pieces of information necessary for data transmission for each panel may be power headroom information (e.g., power headroom report (PHR)). Power headroom information may refer to the remaining power other than the power used by the terminal for data transmission. Power headroom information may be set on a subframe basis. The transmission power for data may be a predicted value (e.g., predicted transmission power) rather than a value used for actual transmission (e.g., actual transmission power). The power used for actual data transmission cannot exceed the maximum transmission power supported by the terminal. The predicted transmission power may exceed the maximum transmission power supported by the terminal. The power headroom information reported by the terminal may have a positive or negative value.

[0132] The PHR can be transmitted from the terminal to the base station through the MAC layer. In other words, the PHR can be included in the MAC CE. A PH (power headroom) index (e.g., a PH value) can be defined in a table (e.g., mapping information between the PH index and the transmission power interval) in a technical specification. In the table, the PH index can be mapped to each transmission power interval. For example, the PH index can indicate PH 0, and the PH 0 can be mapped to -23dB ≤ PH < -22dB in the table. The size of the PHR field included in the MAC CE can vary depending on the number of PH indices. The terminal can transmit the PHR per panel. The path loss associated with the PHR can be determined based on the RS (reference signal) linked to the beam configuration (e.g., TCI state and / or QCL). Whether to transmit the PHR per panel can be determined depending on the terminal capability. For example, some terminals may support per-panel PHR transmission, while others may not. A terminal may report to the base station information regarding whether it supports per-panel PHR transmission. A parameter indicating whether PHR transmission for mTRP is supported (e.g., twoPHRmode) may be used as a parameter for information regarding whether per-panel PHR transmission is supported. Methods for improving the performance of uplink communication in an mTRP environment (e.g., an mTRP system) are needed.

[0133] Figure 9 is a conceptual diagram illustrating an embodiment of an asymmetric TRP system.

[0134] Referring to FIG. 9, a macro cell (e.g., a macro TRP, a first TRP) can cover a relatively large area, and a micro cell (e.g., a micro TRP, a second TRP) can cover a relatively small area. Downlink traffic (e.g., traffic for downlink data transmission) may be greater than uplink traffic (e.g., traffic for uplink data transmission). Therefore, transmission resources may be biasedly set with a focus on the downlink. The transmission power of the base station may be greater than the transmission power of the terminal, and the downlink coverage may be wider than the uplink coverage.

[0135] A microcell (e.g., a second TRP) adjacent to a terminal may exist. The power efficiency of uplink communication for the adjacent microcell may be better than the power efficiency of uplink communication for the macrocell (e.g., the first TRP) to which the terminal is connected. A TRP may be an entity that transmits and receives data with the terminal. A TRP and a cell may have corresponding meanings. A TRP may be used with the same meaning as a cell depending on the context. A cell may be used with the same meaning as a TRP depending on the context. A specific TRP (e.g., a serving cell) may perform a control function for another TRP (e.g., a TRP dependent on the specific TRP). A specific TRP may perform a data scheduling function.

[0136] While a terminal performs DL (downlink) communication with a macro cell, the terminal can perform UL (uplink) communication with a micro cell. If channel reciprocity is established between the DL channel for the macro cell and the UL channel for the micro cell, the terminal can determine (e.g., set) the transmission power for the UL channel of the micro cell based on the path loss determined based on the RS received from the macro cell. Alternatively, in an asymmetric TRP system, the terminal can perform DL communication with one TRP (e.g., a macro cell) and UL communication with multiple TRPs (e.g., a macro cell and a micro cell). In the above-described asymmetric TRP system, the terminal can determine (e.g., set) the transmission power for the UL channel of each of the macro cell and the micro cell based on the path loss determined based on the RS received from the macro cell. In this case, the UL transmission power for the micro cell can be set to a high power. In other words, since the UL transmission power for a microcell is determined by considering the channel status between the macrocell and the terminal, rather than the channel status between the microcell and the terminal, the UL transmission power for the microcell can be set to high power. Although UL communication (e.g., transmission of a channel and / or signal) for the microcell is possible using low transmission power, UL communication for the microcell may be performed using high transmission power. Therefore, the power of the terminal may be wasted, and UL communication using high transmission power may cause interference to other terminals.

[0137] To address the above-described issues, a method for setting UL transmission power in an asymmetric TRP system may require supplementation. The asymmetric TRP system may include mTRPs, wherein among the mTRPs, an sTRP may perform DL communication, and the mTRP may perform UL communication. An sTRP performing DL communication may be referred to as a DL sTRP. An mTRP performing UL communication may be referred to as a UL mTRP. A method for power control (e.g., power setting, power determination) for UL communication in an asymmetric TRP system will be described. While the present disclosure describes a power control method for a PUSCH, the power control method for a PUSCH may be applicable to other UL channels and / or other UL signals. In an asymmetric TRP system, the transmission power for a UL mTRP may be determined by considering a path loss determined based on a reference signal received from the sTRP. In other words, in the embodiment of FIG. 9, the first transmit power for the first TRP may be determined based on the measurement result of the reference signal received from the first TRP, and the second transmit power for the second TRP may be determined based on the measurement result of the reference signal received from the first TRP. An additional path loss compensation method may be required for each UL mTRP.

[0138] The transmission power of the PUSCH can be determined based on the following mathematical expression 1. For example, in the embodiment of FIG. 9, the first transmission power for the first TRP can be determined based on the following mathematical expression 1.

[0139]

[0140] PUSCH occasion i is the slot index within the SFN (system frame number). can be defined as μ can be the subcarrier spacing (SCS) for PUSCH. s can be the start symbol of PUSCH. may refer to the carrier of the serving cell (c). PUSCH may be set in a section of length L from the start symbol (s). can be used as an argument to distinguish between sets of parameters (e.g., parameter groups). can be used as a factor for distinguishing the power control adjustment state. b can be used to indicate the active BWP in which the PUSCH is transmitted. can indicate the resource index of RS for measuring path loss.

[0141] A base station (e.g., the first TRP in FIG. 9) may transmit, via RRC signaling, configuration information of a serving cell, information about candidate TCI states (e.g., a TCI state pool), and / or configuration information about power control according to each TCI state (e.g., , , PUSCH power control adjustment state ( )) can be transmitted to the terminal. The terminal can receive the above information through the RRC signaling of the base station. Information on candidate TCI states and / or setting information on power control according to each TCI state may be provided by the resource index of RS for measuring path loss ( ) may be included. The terminal may determine (e.g., set, control) the transmission power for UL communication (e.g., PUSCH transmission) based on the TCI state and power setting information associated with the TCI state. In the present disclosure, the base station may be interpreted as a macro cell (e.g., macro TRP, first TRP) in FIG. 9 depending on the context.

[0142] 1. Proposal #1: Establishing / instructing additional power control via RRC signaling

[0143] A base station (e.g., the first TRP of FIG. 9) can transmit to a terminal a configuration (e.g., an indication) of additional power control for UL communication (e.g., UL transmission) via signaling (e.g., RRC signaling). The terminal can receive the configuration of additional power control for UL communication via signaling from the base station. The configuration of additional power control can include condition(s) for which additional power control is determined to be necessary and / or value(s) of additional power control that satisfy the condition(s). The value of the additional power control can be an absolute value or a relative value. The relative value of the additional power control can be a transmission power value based on an existing rule. Alternatively, the relative value of the additional power control can be a part of a transmission power value based on an existing rule. If the configuration of the additional power control is transmitted via RRC signaling, dynamic control of the additional power (e.g., control by DCI or MAC CE) may not be possible. When RRC signaling is used, the location characteristics of the base station can be utilized and signaling overhead can be reduced.

[0144] A. Proposal #1-1

[0145] The base station can set (e.g., instruct) the terminal to set a single variable (e.g., a quality threshold, a quality range) related to a specific condition considering coverage between TRPs, a value related to the single variable, and / or a power offset (e.g., an additional offset, a correction factor) of the transmission power related to the specific condition. The terminal can check the information set by the base station. The quality threshold can be an RSRP threshold, an RSRQ (reference signal received quality) threshold, and / or an SINR threshold. The quality range can be an RSRP range, an RSRP range, and / or an SINR range. The quality threshold and the quality range can have corresponding meanings. When the set conditions (e.g., RSRP threshold, RSRQ threshold, SINR threshold, RSRP range, RSRQ range, SINR range) are satisfied (e.g., when the measurement result of RS falls within a specific range, when the measurement result of RS is lower than or equal to a specific threshold, and / or when the measurement result of RS is higher than or equal to a specific threshold), the terminal may determine the transmission power by applying the power offset set by the base station. The terminal may perform UL communication using the determined transmission power. The measurement result of RS may be the measurement result of RS received from the first TRP in FIG. 9, and the transmission power may be the UL transmission power for each of the first TRP and the second TRP in FIG. 9.

[0146] The power offset (e.g., additional offset) of the transmit power according to the RSRP for the signal (e.g., RS) received from the sTRP (e.g., the first TRP of FIG. 9) may be defined as shown in Table 2 below. The power offset of the transmit power may vary depending on the RSRP for the signal received from the sTRP. The offset in Table 2 is defined as the transmit power (e.g., ) can be additionally applied.

[0147]

[0148] In Table 2, the RSRP thresholds (e.g., RSRP ranges) can be -A, -B, -C, ..., -F, -G, and / or -H. The base station can inform the terminal of the RSRP thresholds (e.g., RSRP ranges) and the power offsets (e.g., additional offsets) associated with the RSRP thresholds through signaling. Alternatively, the base station can set (e.g., instruct) the terminal to set (e.g., instruct) the index(es) of Table 2 through signaling. In this case, Table 2 can be predefined in the technical specification. In other words, Table 2 can be pre-set in the base station and / or the terminal. For example, the base station can indicate (e.g., set) the indices [0, 6] of Table 2 to the terminal through signaling. In this case, the terminal can determine the transmit power by considering the power offset (+a) corresponding to the index 0 and / or the power offset (-f) corresponding to the index 6. A reference signal for RSRP measurement may be a reference signal received from a serving cell (e.g., the first TRP in FIG. 9). The reference signal may include a synchronization signal (e.g., SSB), a reference signal for measuring a channel state (e.g., CSI-RS), etc. Alternatively, the base station may determine a power offset (e.g., an additional offset for transmission power) based on a measurement result of the uplink reference signal, and may inform the terminal of the power offset through signaling (e.g., RRC signaling). The terminal may receive the power offset through the signaling of the base station, and determine the transmission power by taking the power offset into consideration. For example, the terminal may determine the UL transmission power for the first TRP in FIG. 9 without considering the power offset, and may determine the UL transmission power for the second TRP in FIG. 9 by taking the power offset into consideration. For example, the UL transmit power for the first TRP can be determined based on Equation 1, and the UL transmit power for the second TRP can be determined based on Equation 2 or Equation 3.The UL transmit power for TRPs can be set independently.

[0149] The base station can transmit a single RSRP threshold (e.g., a single RSRP range) and a power offset corresponding to the single RSRP threshold (e.g., a single power offset) to the terminal via signaling (e.g., RRC signaling). The terminal can check the single RSRP threshold and the power offset via signaling from the base station. If the condition for the single RSRP threshold is satisfied, the terminal can determine the transmission power by applying the power offset corresponding to the single RSRP threshold.

[0150] B. Proposals #1-2

[0151] Although the signaling overhead for the above-described Proposal #1-1 may be low, since only the measurement result for a single TRP is considered in Proposal #1-1, the distance between the TRP where the actual UL communication is performed and the terminal may not be considered. If multiple TRPs are not considered, the communication performance and / or energy efficiency may be reduced. In Proposal #1-2, the base station can set multiple quality thresholds (e.g., multiple quality ranges), and can signal (e.g., set) the multiple quality thresholds and the power offsets (e.g., additional offsets, correction factors) associated with the multiple quality thresholds to the terminal.

[0152] The number of multiple quality thresholds may be set equal to the number of TRPs subject to channel measurement. For example, a first quality threshold may be set for a first TRP, and a second quality threshold may be set for a second TRP. If all quality thresholds set by the base station are satisfied, the terminal may determine (e.g., set, adjust, control) the transmission power by applying a power offset associated with the quality thresholds, and may perform UL communication using the transmission power.

[0153] The power offset (e.g., additional offset) of the transmit power according to RSRP for a signal (e.g., RS) received with multiple TRPs can be defined as shown in Table 3 below. If the terminal supports up to two TRPs, the power offset associated with two RSRP thresholds can be set.

[0154]

[0155] In Table 3, the RSRP thresholds (e.g., RSRP ranges) may be -A1, -A2, -B1, -B2, -C1, -C2, ... , -F1, -F2, -G1, -G2, -H1, and / or -H2. -A1, -B1, -C1, ... , -F1, -G1, and / or -H1 may be RSRP thresholds (e.g., RSRP ranges) for the first TRP of FIG. 9. -A2, -B2, -C2, ... , -F2, -G2, and / or -H2 may be RSRP thresholds (e.g., RSRP ranges) for the second TRP of FIG. 9. The RSRP threshold for the first TRP may be referred to as RSRP threshold 1. The RSRP threshold for the second TRP may be referred to as RSRP threshold 2. The base station may use all or part of Table 3. The base station can signal (e.g., set) the index(es) corresponding to [RSRP threshold 1, RSRP threshold 2, power offset] used in Table 3 to the terminal. The terminal can check the index(es) indicated by the signaling of the base station. Table 3 can be predefined in the technical specification. In other words, Table 3 can be pre-set in the base station and / or the terminal, and the base station can inform the terminal of the index(es) corresponding to [RSRP threshold 1, RSRP threshold 2, power offset] used in Table 3.

[0156] Alternatively, the base station can transmit a set of quality thresholds and a power offset associated with the set of quality thresholds to the terminal via signaling (e.g., RRC signaling). The terminal can check the set of quality thresholds and the power offset via signaling from the base station. The set of quality thresholds can include a quality threshold (e.g., an RSRP threshold) corresponding to each of a plurality of TRPs. The set of quality thresholds can include [RSRP threshold 1, RSRP threshold 2]. The power offset can be set for each quality threshold set. In Table 3, a plurality of quality thresholds (e.g., -A1, -A2) associated with index 0 can be set as one quality threshold set. The terminal can compare the measurement results of reference signals received from a plurality of TRPs (e.g., the first TRP and the second TRP in FIG. 9) belonging to the same cell or different cells with the quality thresholds belonging to the quality threshold set.

[0157] For example, a set of quality thresholds may include two quality thresholds, and the terminal may receive a reference signal from each of four TRPs. In this case, if there are TRPs that satisfy the quality threshold(s), the terminal may determine the transmission power by applying a power offset associated with the quality threshold(s), and may perform UL communication with the TRP(s) using the transmission power. If there are multiple TRP pairs, the terminal may identify the TRP pair(s) that satisfy the conditions of the quality threshold(s) at a time closest to the time when the UL transmission is triggered, and may perform UL communication with the identified TRP pair(s) using the power offset(s) associated with the quality threshold(s).

[0158] Alternatively, if there are TRP pairs that satisfy the conditions of the quality thresholds within the time interval in which the UL transmission exists, the terminal can determine the transmission power using the power offset associated with the lowest quality threshold among the quality thresholds. The base station can transmit to the terminal information necessary for distinguishing the TRP (e.g., TRP ID) and information about the quality threshold corresponding to the TRP (e.g., quality range) through signaling. The terminal can receive information necessary for distinguishing the TRP and information about the quality threshold corresponding to the TRP through signaling from the base station. The terminal can distinguish the TRP(s) that the terminal is measuring based on the information received from the base station and derive the reception performance for each TRP.

[0159] C. Proposals #1-3

[0160] In the above-described Proposal #1-1 and / or Proposal #1-2, the power offset can be used to determine the transmit power of the terminal. In the first method, the terminal can determine the final transmit power by adding the power offset to the transmit power in the PUSCH occasion i, which is determined based on Equation 1. In other words, the final transmit power can be [the transmit power based on Equation 1 + the power offset]. Equation 1 can be a mathematical formula that does not consider an asymmetric TRP system. [the transmit power based on Equation 1 + the power offset] may not exceed the maximum transmit power supported by the terminal. The terminal can perform UL communication using [the transmit power based on Equation 1 + the power offset]. In other words, the terminal can determine the transmit power based on Equation 2 below. In Equation 2, the offset can be the power offset determined in Equation 1-1 and / or Equation 1-2. In FIG. 9, the UL transmit power for the first TRP can be determined based on Equation 1, and in FIG. 9, the UL transmit power for the second TRP can be determined based on Equation 2. The UL transmit power for the second TRP can be the sum of the UL transmit power for the first TRP and a power offset. The power offset can have a negative or positive value.

[0161]

[0162] In a second method, the power offset determined in Proposal #1-1 and / or Proposal #1-2 can be used as a correction factor for a specific parameter. In other words, the power offset can be interpreted as a correction factor. The terminal can determine the corrected specific parameter by applying the correction factor to the specific parameter in Equation 1, and can determine the transmission power using Equation 1 reflecting the corrected specific parameter. For example, in Equation 1, the path loss ( ) which represents the correction factor for the ) can have a value between 0 and 1. The value mapped to the power offset determined in Proposal #1-1 and / or Proposal #1-2 is can be defined as may be a correction factor for path loss (e.g., path loss for the DL channel between the first TRP and the terminal in Fig. 9). In Equation 1, Is can be replaced with. In other words, the terminal can determine the transmission power based on the following mathematical expression 3. In FIG. 9, the UL transmission power for the first TRP can be determined based on the mathematical expression 1, and in FIG. 9, the UL transmission power for the second TRP can be determined based on the mathematical expression 3.

[0163]

[0164] D. Proposals #1-4

[0165] In the procedure for transmitting configuration information of a TCI state pool, the base station can transmit information on a path loss RS associated with each TCI state to the terminal. The terminal can receive information on a path loss RS associated with each TCI state from the base station. In other words, the configuration information of the TCI state pool can include information on a path loss RS associated with each TCI state. If there is an update of an RS associated with a TCI state (e.g., a path loss RS), the base station can transmit information on the updated RS to the terminal using a MAC CE. The terminal can receive information on the updated RS from the base station.

[0166] Alternatively, in the TCI state activation procedure using MAC CE, the base station can transmit to the terminal not only information on the TCI state(s) to be activated but also information on the path loss RS associated with each TCI state. The terminal can receive information on the path loss RS associated with each TCI state from the base station. In other words, the MAC CE for TCI state activation can include information on the TCI state(s) to be activated and information on the path loss RS associated with each TCI state. The terminal can determine the transmission power using the path loss RS associated with the TCI state(s).

[0167] 2. Proposal #2: Setting / instructing additional power control via DCI and / or MAC CE

[0168] RRC signaling can convey more information than other signaling methods (e.g., DCI, MAC CE). However, because RRC signaling has a long latency, it is difficult to transmit dynamic information through RRC signaling. Although the amount of information that can be transmitted through DCI may be small, DCI signaling may have an advantage over other signaling methods (e.g., RRC signaling, MAC CE) in terms of latency because DCI signaling requires only a PDCCH decoding procedure without scheduling. DCI signaling can be used to transmit dynamic information. Because MAC CE signaling requires scheduling, MAC CE signaling may have a disadvantage compared to DCI signaling in terms of latency. The amount of information that can be transmitted through MAC CE may be greater than that of DCI. In Proposal #2, methods for controlling the transmit power of the PUSCH using DCI and / or MAC CE in an asymmetric TRP system will be described.

[0169] DCI format 0_X can be used for UL communication (e.g., PUSCH transmission), and DCI format 1_X can be used for DL ​​communication (e.g., PDSCH transmission). DCI format 2_X can be common DCI. DCI format 3_X can be used for SL communication. DCI format 4_X can be used for multicast / broadcast communication. X can be an integer greater than or equal to 0.

[0170] DCI format 0_3 can be used for scheduling multiple PUSCH transmissions for multiple cells. DCI format 0_3 can include resource allocation information, decoding information, and / or power control information corresponding to the number of PUSCH transmissions (e.g., the number of cells required for PUSCH transmissions). The resource allocation information, decoding information, and / or power control information can be dynamically allocated by DCI format 0_3. Information on path loss RS required for power control for RBs allocated for PUSCH transmission can be transmitted to a terminal via RRC signaling of a base station. The terminal can determine the transmission power for uplink per cell based on the path loss RS indicated by the base station.

[0171] In an asymmetric TRP system, a UE can perform DL communication with one TRP and UL communication with multiple TRPs. In this case, it may be difficult to individually indicate (e.g., configure) reference signals (e.g., path loss RS) for PUSCH resources of each cell (e.g., each TRP). Therefore, a new DCI format and / or a new radio network temporary identifier (RNTI) may be required for the asymmetric TRP system. Alternatively, existing DCI formats for scheduling multiple TRPs may be reused for the asymmetric TRP system.

[0172] In the present disclosure, a TRP that transmits a DL signal to a terminal may be defined as a primary serving cell (PSC), and a TRP (e.g., a target TRP) that receives a UL signal from the terminal may be defined as a secondary serving cell (SSC). In FIG. 9, a first TRP may be a PSC, and in FIG. 9, the first TRP and / or the second TRP may be SSCs. Path loss, which is one of the parameters used to determine the transmit power of a UL transmission (e.g., a PUSCH transmission) for an SSC in an asymmetric TRP system, may be determined based on an RS received from the PSC. Accordingly, a base station may transmit a power offset for each TRP (e.g., each SSC) to a terminal using DCI and / or MAC CE. The terminal may obtain the power offset for each TRP from the base station.

[0173] A correction factor for path loss set by RRC signaling ( ), the correction factor for each TRP ( ) can be applied independently, the PSC can transmit to the terminal the values ​​of the correction coefficients corresponding to the number of SSCs. The terminal can obtain the values ​​of the correction coefficients from the PSC. In other words, the correction coefficients ( set by RRC signaling ) is a value for PSC, the correction factor(s) for SSC(s) can be additionally set (e.g., indicated) in the terminal. Correction factor for path loss( ) can have a value between 0 and 1. Due to the problem of quantization, the correction factor ( ) can be difficult to transmit quantized bits over DCI. The correction factor ( ) can be interpreted as a power offset in the above-mentioned proposal #1. The correction factor can be determined based on the power offset.

[0174] Considering the characteristics of the asymmetric TRP system, the correction factor for PSC set by RRC signaling ( ), additional correction factor(s) for SSC(s) may be introduced. In order to transmit the additional correction factor(s) via DCI and / or MAC CE, the additional correction factor(s) may have an appropriate quantization level. The base station may transmit the DCI and / or MAC CE including UL scheduling information of each SSC and / or power control information of each SSC (e.g., additional correction factor) to the terminal. The terminal may receive the DCI and / or MAC CE from the base station, and may check the UL scheduling information of each SSC and / or power control information of each SSC (e.g., additional correction factor) included in the DCI and / or MAC CE.

[0175] To support the above-described operation, in the UE capability reporting procedure, the terminal may inform the base station whether the terminal supports the operation of determining the transmission power based on the additional correction factor of each SSC. If the power control information (e.g., the additional correction factor) of each SSC is transmitted through a single DCI and / or a single MAC CE, the scheduling information (e.g., decoding information) and / or power control information for each SSC may be located in the mapping order of the CORESET index associated with the TRP (e.g., SSC) within the single DCI and / or single MAC CE.

[0176] Alternatively, the base station may transmit the candidate correction factor pools available for each SSC to the terminal via RRC signaling, instruct the terminal to activate (or deactivate) one or more correction factor pools among the candidate correction factor pools via MAC CE signaling, and instruct the terminal via DCI signaling the codepoint for one or more correction factors within the activated correction factor pool(s). The terminal may identify one or more correction factors (e.g., additional correction factor(s)) based on the RRC signaling, MAC CE signaling, and / or DCI signaling of the base station. A single codepoint may be associated with additional correction factors corresponding to a maximum number of SSCs.

[0177] The number of bits in the field indicating the correction factor (e.g., candidate correction factor) for path loss per SSC may vary depending on the quantization level of the correction factor. For example, if the value of the candidate correction factor that can be transmitted per SSC is N, the number of bits in the field indicating the candidate correction factor in the DCI and / or MAC CE is can be. N can be a natural number. If the maximum number of TRPs performing UL communication with the terminal is M, the number of bits in the field indicating the candidate correction factor within the DCI and / or MAC CE is M may be a natural number. The base station and / or the terminal may determine the size of the field indicating the candidate correction factor within the DCI and / or MAC CE based on the values ​​of N and / or M.

[0178] The base station can transmit to the terminal information on whether UL power control (e.g., UL transmit power) is applied differently for each SSC using RRC signaling and / or MAC CE signaling. The terminal can receive the information through the RRC signaling and / or MAC CE signaling of the base station. If the UL power control (e.g., UL transmit power) is applied differently for each SSC, the terminal can independently determine the UL transmit power of each SSC. For example, the terminal can determine the UL transmit power of the first SSC (e.g., the first TRP of FIG. 9) based on Equation 1, and the terminal can determine the UL transmit power of the second SSC (e.g., the second TRP of FIG. 9) based on Equation 2 or Equation 3. Whether the UL power control is applied differently for each SSC can be determined according to the terminal capability. The base station can determine whether the UL power control is applied differently for each SSC by taking into consideration the terminal capability. If UL power control is indicated to be applied differently for each SSC (or if UL power control is indicated to be applied equally across SSCs), the indication may remain in effect until further signaling. Alternatively, the indication may remain in effect for a specific period indicated by the base station. In this case, the degree of freedom in power control may be enhanced.

[0179] A base station can generate a DCI including a field indicating the number (M) of TRPs performing UL communication with a terminal, and transmit the DCI to the terminal. The terminal can receive the DCI from the base station and, based on the field included in the DCI, determine the number of TRPs performing UL communication with the terminal. The size of the field indicating the number (M) of TRPs performing UL communication with the terminal is It can be. Based on the number of TRPs performing UL communication with the terminal indicated by the field included in the DCI, the terminal can predict how many SSCs the DCI includes information on correction coefficients, and can expect to decode the correction coefficients for the SSCs based on the predicted information. Bits corresponding to the number (M) of SSCs that the terminal can support in the DCI can be allocated, and each bit can indicate whether path loss is corrected for each SSC (e.g., each TRP).

[0180] A correction factor for SSCs (e.g., a path loss correction factor) can be conveyed via the MAC CE. If the number of SSCs (M) changes frequently, the overhead for blind decoding at the terminal may increase. Therefore, the number of SSCs (M) can be conveyed via the MAC CE.

[0181] The base station can instruct the terminal through the MAC CE whether to "support UL power control for each SSC" or "activate or deactivate UL power control for each SSC." The terminal can check the information indicated by the MAC CE of the base station. The number of SSCs related to the information indicated by the MAC CE can correspond to the number of PUSCH scheduling information indicated by the DCI after the MAC CE. The base station can notify the terminal in advance that it performs UL power control for all or some SSCs. The size of the field indicating the above information in the MAC CE is may be identical or similar. M may be the number of SSCs.

[0182] When activation of UL power control for specific SSC(s) is instructed, the terminal can determine UL power (e.g., transmit power) for the specific SSC(s) based on a correction factor (or power offset) of path loss until deactivation of UL power control for the specific SSC(s) is instructed, and perform UL communication with the specific SSC(s) using the determined UL power. The method of applying the correction factor transmitted via DCI and / or MAC CE may be the same as or similar to Proposal #1-3.

[0183] In the present disclosure, the maximum number of TRPs may be interpreted as the maximum number of UL TCI states supported by the terminal. In other words, the maximum number of TRPs may be independent of the TCI state type. If two TRPs are supported and the TCI state type is an independent type, four TCI states are set in the terminal, but since the maximum number of UL TCI states supported by the terminal is two, the maximum number of TRPs may be two. The maximum number of TRPs (e.g., the maximum number of UL TCI states) may be interpreted as the maximum number of TRPs (M) associated with information transmitted by the DCI and / or MAC CE. The field(s) in the DCI and / or MAC CE may be associated with the TCI state(s) in descending order.

[0184] The terminal can determine (e.g., set, adjust, control) the UL transmission power based on one or a combination of proposals from among proposal #1 or proposal #2 proposed in the present disclosure. The embodiments proposed in the present disclosure can be applied not only to power control of UL-SCH (e.g., PUSCH) transmission for an activated serving cell, but also to transmit power control of other uplink signals / channels (e.g., SRS, PUCCH).

[0185] A terminal may transmit information indicating whether it supports the function(s) proposed in this disclosure to a base station. For example, in a UE capability reporting procedure, the terminal may transmit information indicating whether it supports the function(s) proposed in this disclosure to the base station. The base station may determine which function(s) are supported by the terminal based on the information received from the terminal. The base station may perform signaling and operations based on the function(s) supported by the terminal (e.g., UE capabilities). The base station may transmit information indicating whether to use the proposal(s) proposed in this disclosure to the terminal using RRC signaling. The terminal may determine which proposal(s) are used through the RRC signaling of the base station.

[0186] The operations of the method according to the present disclosure can be implemented as a computer-readable program or code on a computer-readable recording medium. A computer-readable recording medium includes any type of recording device that stores information readable by a computer system. Furthermore, a computer-readable recording medium can be distributed across network-connected computer systems, allowing the computer-readable program or code to be stored and executed in a distributed manner.

[0187] Additionally, the computer-readable recording medium may include hardware devices specifically configured to store and execute program instructions, such as ROM, RAM, flash memory, etc. The program instructions may include not only machine language codes produced by a compiler, but also high-level language codes that can be executed by a computer using an interpreter, etc.

[0188] While some aspects of the present disclosure have been described in the context of a device, they may also represent a description of a corresponding method, wherein a block or device corresponds to a method step or a feature of a method step. Similarly, aspects described in the context of a method may also be described as a 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 or more of the most significant method steps may be performed by such a device.

[0189] A programmable logic device (e.g., a field-programmable gate array) may be used to perform some or all of the functions of the methods described in the present disclosure. The field-programmable gate array may operate in conjunction with a microprocessor to perform one of the methods described in the present disclosure. In general, the methods are preferably performed by some hardware device.

[0190] Although the present disclosure has been described with reference to preferred embodiments thereof, it will be understood by those skilled in the art that various modifications and changes may be made to the present disclosure without departing from the spirit and scope of the present disclosure as set forth in the claims below.

Claims

1. As a method of UE (user equipment), A step of performing DL (downlink) communication with the first TRP (transmission and reception point); A step of determining a first UL (uplink) transmission power for a first UL communication with the first TRP based on a state of a DL channel between the UE and the first TRP; A step of performing the first TRP and the first UL communication using the first UL transmission power; A step of determining a second UL transmission power for a second UL communication with a second TRP based on the state and power offset of the DL channel between the UE and the first TRP; and A step of performing the second TRP and the second UL communication using the second UL transmission power, UE's method.

2. In claim 1, The step of determining the second UL transmission power is: A step of measuring the quality of the DL channel based on a reference signal received from the DL channel; A step of confirming the quality range to which the measured quality belongs; and comprising a step of checking the power offset mapped to the quality range; UE's method.

3. In claim 2, Further comprising the step of receiving mapping information between one or more quality ranges and one or more power offsets, The above quality range and the above power offset are confirmed based on the above mapping information, UE's method.

4. In claim 3, The above mapping information is received through RRC (radio resource control) signaling of the first TRP. UE's method.

5. In claim 2, The above measured quality is RSRP (reference signal received power), and the above quality range is RSRP range or RSRP threshold. UE's method.

6. In claim 1, The above second UL transmission power is the sum of the first UL transmission power and the power offset. UE's method.

7. In claim 1, The step of determining the second UL transmission power is: A step of determining a correction factor for path loss for the DL channel based on the power offset; and A step of determining the second UL transmission power based on the path loss in which the correction factor is reflected, UE's method.

8. In claim 1, Further comprising a step of receiving a MAC (medium access control) CE (control element) or DCI (downlink control information) including a correction factor corresponding to the power offset from the first TRP, The above second UL transmission power is determined based on the path loss to which the correction factor is reflected. UE's method.

9. In claim 8, Further comprising the step of receiving RRC signaling including a plurality of correction factors from the first TRP, The correction factor indicated by the MAC CE or the DCI is one of the plurality of correction factors indicated by the RRC signaling. UE's method.

10. In claim 1, Further comprising the step of receiving information from the first TRP indicating that the UL transmission power is applied differently for each TRP, If it is indicated that the above UL transmission power is applied differently for each TRP, the first UL transmission power and the second UL transmission power are independently determined. UE's method.

11. As a UE (user equipment), Contains at least one processor, At least one processor of the UE, Performs DL (downlink) communication with the first TRP (transmission and reception point); Determine a first UL (uplink) transmission power for a first UL communication with the first TRP based on a state of a DL channel between the UE and the first TRP; Performing the first TRP and the first UL communication using the first UL transmission power; Determine a second UL transmission power for a second UL communication with a second TRP based on the state and power offset of the DL channel between the UE and the first TRP; and Causing the second TRP and the second UL communication to be performed using the second UL transmission power, UE.

12. In claim 11, In the step of determining the second UL transmission power, the at least one processor is configured to cause the UE to: Measuring the quality of the DL channel based on a reference signal received from the DL channel; Identify the quality range to which the measured quality belongs; and causing the power offset to be mapped to the above quality range to be verified, UE.

13. In claim 12, At least one processor of the UE, further causes to receive mapping information between one or more quality ranges and one or more power offsets, The above quality range and the above power offset are confirmed based on the above mapping information, UE.

14. In claim 13, The above mapping information is received through RRC (radio resource control) signaling of the first TRP. UE.

15. In claim 12, The above measured quality is RSRP (reference signal received power), and the above quality range is RSRP range or RSRP threshold. UE.

16. In claim 11, The above second UL transmission power is the sum of the first UL transmission power and the power offset. UE.

17. In claim 11, In the step of determining the second UL transmission power, the at least one processor is configured to cause the UE to: Determine a path loss correction factor for the DL channel based on the power offset; and Causing the second UL transmission power to be determined based on the path loss in which the correction factor is reflected, UE.

18. In claim 11, At least one processor of the UE, Further causing MAC (medium access control) CE (control element) or DCI (downlink control information) including a correction factor corresponding to the power offset to be received from the first TRP, The above second UL transmission power is determined based on the path loss to which the correction factor is reflected. UE.

19. In claim 18, At least one processor of the UE, further causes the RRC signaling including a plurality of correction factors to be received from the first TRP, The correction factor indicated by the MAC CE or the DCI is one of the plurality of correction factors indicated by the RRC signaling. UE.

20. In claim 11, At least one processor of the UE, Further causing information to be received from the first TRP indicating that the UL transmission power is applied differently for each TRP, If it is indicated that the above UL transmission power is applied differently for each TRP, the first UL transmission power and the second UL transmission power are independently determined. UE.

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