Method performed by terminal or network in wireless communication system, and apparatus therefor

Abstract

A terminal according to an embodiment of the present disclosure may: receive configuration information related to uplink precoding; and transmit a precoded uplink signal on the basis of the configuration information, wherein resources for the uplink signal comprise one or more frequency resource units and one or more time resource units, and the uplink signal may be precoded on the basis of precoder cycling for at least one of each frequency resource unit and / or each time resource unit.

Description

A method performed by a terminal or network in a wireless communication system and an apparatus for the same

[0001] The present disclosure relates to a wireless communication system, and more specifically, to a method for transmitting or receiving uplink / downlink signals between terminals or networks in a wireless communication system and an apparatus for the same.

[0002] The 5G mobile communication system is a successor technology to LTE (Long Term Evolution) and is a new clean-slate type of mobile communication system characterized by high performance, low latency, and high availability. In the case of 5G NR, all available spectrum resources can be utilized, ranging from low-frequency bands below 1 GHz to intermediate frequency bands between 1 GHz and 10 GHz, and high-frequency (millimeter wave) bands above 24 GHz. Based on the underlying technology of 5G mobile communication, 6G mobile communication systems are being developed.

[0003] Currently, NR supports codebook-based UL transmission and non-codebook-based UL transmission. These transmission techniques use the same precoder for uplink transmission across the entire UL band configured by the base station on the terminal. These transmission techniques may experience performance degradation in frequency-selective channels and may also result in performance degradation in situations where the terminal has high mobility.

[0004] In next-generation communication systems including 6G, more flexible and efficient UL MIMO transmission techniques need to be supported.

[0005] The technical problem to be solved by the present disclosure is to provide a method for efficiently performing a wireless signal transmission and reception process and an apparatus for doing so. For example, a (semi)-open loop (OL) transmission method is proposed in uplink transmission. As a more specific example of a (semi)-OL method, a UL precoder cycling method may be provided. In addition, a method for determining and directing a codebook used when UL precoder cycling is applied may be provided.

[0006] In addition to the technical challenges described above, other technical challenges can be inferred from the description below.

[0007] According to one aspect of the present disclosure, a method performed by a terminal comprises receiving configuration information related to uplink precoding; and transmitting an uplink signal precoded based on said configuration information, wherein the resources for the uplink signal include one or more frequency resource units and one or more time resource units, and the uplink signal may be precoded based on precoder cycling for at least one of each frequency resource unit and / or each time resource unit.

[0008] The above setting information may include information about the precorders for the precorder cycle.

[0009] The above precoders may be a subset of an uplink codebook, a subset of a downlink codebook, or a subset of a precoder cycle-only codebook.

[0010] The above terminal can precode the uplink signal by circulating precoders in a specific order for each combination of frequency resource unit and each time resource unit.

[0011] The specific order mentioned above may be a frequency first mapping order, a time first mapping order, or a time-frequency circular mapping order.

[0012] The above precorder cycle can be performed based on at least one of the index of the precorder, the index of each frequency resource unit, and / or the index of each time resource unit.

[0013] The above terminal can receive DCI (downlink control information) that schedules the uplink signal.

[0014] The above DCI may include at least one of information about the precorders for the precorder cycle or information about the cycle order of the precorders.

[0015] The above uplink signal may be a PUSCH (physical uplink shared channel).

[0016] The above PUSCH is a CG (configured grant)-PUSCH, and the above configuration information may include CG configuration information.

[0017] The above precoder cycle may be a codebook-based precoder cycle or a non-codebook-based precoder cycle using an SRS (sounding reference signal).

[0018] According to another aspect of the present disclosure, a computer-readable non-transitory recording medium may be provided that records a program for performing the method described above.

[0019] An apparatus according to another aspect of the present disclosure comprises: at least one processor; and at least one memory configured to store instructions that are executed by the at least one processor to cause the at least one processor to perform operations, wherein the operations of the processor include receiving configuration information related to uplink precoding; and transmitting an uplink signal precoded based on the configuration information, wherein resources for the uplink signal include one or more frequency resource units and one or more time resource units, and the uplink signal may be precoded based on precoder cycling for at least one of each frequency resource unit and / or each time resource unit.

[0020] The above device may be a terminal including a transceiver or a processing device configured to control the terminal.

[0021] According to another aspect of the present disclosure, a method performed by a base station comprises: transmitting configuration information related to uplink precoding; and receiving an uplink signal precoded based on said configuration information, wherein the resources for said uplink signal include one or more frequency resource units and one or more time resource units, and said uplink signal may be precoded based on precoder cycling for at least one of each frequency resource unit and / or each time resource unit.

[0022] A base station according to another aspect of the present disclosure comprises at least one processor; and at least one memory configured to store instructions that are executed by the at least one processor to cause the at least one processor to perform operations, wherein the operations of the processor include transmitting configuration information related to uplink precoding; and receiving an uplink signal precoded based on the configuration information, wherein resources for the uplink signal include one or more frequency resource units and one or more time resource units, and the uplink signal may be precoded based on precoder cycling for at least one of each frequency resource unit and / or each time resource unit.

[0023] According to the present disclosure, signal transmission and reception can be performed efficiently in a wireless communication system. According to one embodiment, UL diversity gain can be obtained by supporting a (semi)-open loop technique, e.g., an UL precoder cycling technique, in the uplink transmission of a terminal, and more robust and reliable transmission and reception of UL signals can be supported in a frequency-selective channel and / or in an environment with high mobility.

[0024] In addition to the technical effects described above, other technical effects can be inferred from the description below.

[0025] FIG. 1 illustrates an exemplary flexible network topology to which some of the examples of the present specification may be applied.

[0026] FIG. 2 illustrates an example of a communication system applicable to the present disclosure.

[0027] FIG. 3 illustrates an example of a wireless device that can be applied to the present disclosure.

[0028] FIG. 4 illustrates a communication procedure between a first node (e.g., a terminal) and a second node (e.g., a base station) applicable to the present disclosure.

[0029] Figure 5 illustrates a general functional architecture for an AI / ML model.

[0030] FIG. 6 illustrates a communication procedure between a first node (e.g., terminal) and a second node (e.g., base station) to which an AI / ML model is applied.

[0031] FIG. 7 shows an electromagnetic spectrum according to one embodiment of the present disclosure.

[0032] FIG. 8 illustrates an example of a procedure for transmitting system information for THz communication to which the present disclosure applies.

[0033] FIG. 9 illustrates a beam management procedure applicable to the present disclosure.

[0034] FIG. 10 shows an example of a sensing operation according to one embodiment of the present disclosure.

[0035] FIG. 11 illustrates a time / frequency resource for a sensing operation according to one embodiment of the present specification.

[0036] FIG. 12 illustrates a procedure related to a sensing operation according to one embodiment of the present specification.

[0037] FIG. 13 is a diagram illustrating UL precoder cycling according to one embodiment.

[0038] Figure 14 is a diagram illustrating non / partial / full coherent in a codebook for single-layer transmission through 4-ports.

[0039] FIG. 15 illustrates an example of a codebook for 2-layer transmission through 4-ports.

[0040] FIG. 16 is a diagram illustrating the operation of a terminal and a base station according to one embodiment.

[0041] FIG. 17 illustrates the flow of a method performed by a terminal according to one embodiment.

[0042] FIG. 18 illustrates the flow of a method performed by a base station according to one embodiment.

[0043] In this specification, "A or B" may mean "only A," "only B," or "both A and B." Alternatively, in this specification, "A or B" may be interpreted as "A and / or B." For example, in this specification, "A, B or C" may mean "only A," "only B," "only C," or "any combination of A, B and C."

[0044] A slash ( / ) or a comma used in this specification may mean "and / or." For example, "A / B" may mean "A and / or B." Accordingly, "A / B" may mean "only A," "only B," or "both A and B." For example, "A, B, C" may mean "A, B or C."

[0045] In this specification, "at least one of A and B" may mean "only A," "only B," or "both A and B." Additionally, in this specification, the expressions "at least one of A or B" or "at least one of A and / or B" may be interpreted as synonymous with "at least one of A and B."

[0046] Additionally, in this specification, "at least one of A, B and C" may mean "only A," "only B," "only C," or "any combination of A, B and C." Also, "at least one of A, B or C" or "at least one of A, B and / or C" may mean "at least one of A, B and C."

[0047] Additionally, parentheses used in this specification may mean "for example." Specifically, when indicated as "control information (ABC)," "ABC" may be described as an example of "control information." For example, "control information" may include DEF as another example. In other words, "control information" in this specification is not limited to "ABC," and "ABC" may be described as an example of "control information." Also, when indicated as "control information (i.e., ABC)," "ABC" may be described as an example of "control information."

[0048] In addition, terms such as "first," "second," etc. in this specification are used solely for the purpose of distinguishing one component from another and are not used to limit the components, nor are they used to limit the order or importance of the components unless specifically limited. Accordingly, a first component in one embodiment of this specification may be referred to as a second component in another embodiment, and likewise, a second component in one embodiment may be referred to as a first component in another embodiment.

[0049] In the following explanation, 'when, if, in case of' can be replaced with 'based on'.

[0050] Technical features described individually within a single drawing in this specification may be implemented individually or simultaneously.

[0051] In this specification, a terminal is a user-side device (user equipment, UE) or a consumer-side device, and may also be referred to as a first node that receives / transmits signals from / to a base station / second node / IAB node / Transmission-Reception Point (TRP). A terminal may correspond to a physical node or a logical node. A terminal may correspond to a user-side endpoint or an intermediate point between other endpoints. In communication between two points not limited to endpoints (including one-to-one / many-to-one / one-to-many / many-to-many communication), a terminal may correspond to a served node. A terminal may be a fixed-location node or a non-fixed-location (or mobile) node.

[0052] In this specification, a Base Station (BS) is a device on the network side and may also be referred to as a second node / IAB node / x-NodeB (x-NodeB, where x may be an abbreviation related to Radio Access Technology (RAT)) / Transmission-Reception Point (TRP). A Base Station may correspond to a physical node or a logical node. A Base Station may correspond to an endpoint on the network side or an intermediate point between other endpoints. In communication between two points not limited to endpoints (including one-to-one / many-to-one / one-to-many / many-to-many communication), a Base Station may correspond to a serving node. A Base Station may be a node with a fixed location or a node with an indefinite location.

[0053] In this specification, higher layer parameters may be set for the terminal, pre-set, or pre-defined. For example, a base station may transmit higher layer parameters to the terminal. For example, the terminal may transmit parameters such as capability to the base station as higher layer parameters. For example, higher layer parameters may be transmitted via RRC (radio resource control) signaling or MAC (medium access control) signaling.

[0054] In this specification, information / state / parameters being "configured" or "pre-configured" may be interpreted as the information / state / parameters being provided / pre-provided to the terminal through pre-defined signaling (e.g., SIB, MAC, RRC) from the base station. In this specification, information / state / parameters being "defined" or "pre-defined" may be interpreted as being known or stored in advance by the base station and the terminal without signaling between the base station and the terminal.

[0055] The technology described in this specification can be used in various wireless communication systems such as CDMA (code division multiple access), FDMA (frequency division multiple access), TDMA (time division multiple access), OFDMA (orthogonal frequency division multiple access), and SC-FDMA (single carrier frequency division multiple access). CDMA can be implemented with wireless technologies such as UTRA (universal terrestrial radio access) or CDMA2000. TDMA can be implemented with wireless technologies such as GSM (global system for mobile communications) / GPRS (general packet radio service) / EDGE (enhanced data rates for GSM evolution). OFDMA can be implemented with wireless technologies such as IEEE (institute of electrical and electronics engineers) 802.11 (Wi-Fi), IEEE 802.16 (WiMAX), IEEE 802-20, E-UTRA (evolved UTRA), LTE (long term evolution), and 5G NR.

[0056] The technology described in this specification can be implemented as 6G wireless technology and applied to various 6G systems. For example, 6G systems may have key factors such as eMBB (enhanced mobile broadband), URLLC (ultra-reliable low latency communications), mMTC (massive machine-type communication), AI (artificial intelligence) integrated communication, tactile internet, high throughput, high network capacity, high energy efficiency, low backhaul and access network congestion, and enhanced data security.

[0057] <Symbols, Abbreviations, Terms>

[0058] - ACK: ACKnowledgement

[0059] - AL: Aggregation Level

[0060] - BM: beam management

[0061] - CB: Code Block

[0062] - CBG: Code Block Group

[0063] - CCE: Control Channel Element

[0064] - CQI: channel quality indicator

[0065] - CRI: CSI-RS (channel state information - reference signal) resource indicator

[0066] - CSI: channel state information

[0067] - CSI-IM: channel state information - interference measurement

[0068] - CSI-RS: channel state information - reference signal

[0069] - DCI: Downlink Control Information

[0070] - DL: Downlink

[0071] - DMRS: demodulation reference signal

[0072] - FDM: frequency division multiplexing

[0073] - FFT: fast Fourier transform

[0074] - HARQ: Hybrid ARQ

[0075] - IFDMA: interleaved frequency division multiple access

[0076] - IFFT: inverse fast Fourier transform

[0077] - L1-RSRP: Layer 1 reference signal received power

[0078] - L1-RSRQ: Layer 1 reference signal received quality

[0079] - MAC: medium access control

[0080] - NACK: Negative ACKnowledgement

[0081] - NZP: non-zero power

[0082] - OFDM: orthogonal frequency division multiplexing

[0083] - PDCCH: physical downlink control channel

[0084] - PDSCH: physical downlink shared channel

[0085] - PMI: precoding matrix indicator

[0086] - PRB: physical resource block

[0087] - PUCCH: Physical Uplink Control CHannel

[0088] - PUSCH: Physical Uplink Shared Channel

[0089] - QCL: quasi co-location

[0090] - RB: resource block

[0091] - RE: resource element

[0092] - REG: Resource Element Group

[0093] - RI: Rank indicator

[0094] - RNTI: Radio Network Temporary Identifier

[0095] - RRC: radio resource control

[0096] - RSSI: received signal strength indicator

[0097] - RV: Redundancy Version

[0098] - Rx: Reception

[0099] - SINR: signal to interference and noise ratio

[0100] - SSB (or SS / PBCH block): synchronization signal block (including primary synchronization signal, secondary synchronization signal and physical broadcast channel)

[0101] - TB: Transport Block

[0102] - TDM: time division multiplexing

[0103] - TRP: transmission and reception point

[0104] - TRS: tracking reference signal

[0105] - Tx: transmission

[0106] - UCI: Uplink Control Information

[0107] - UE: user equipment

[0108] - UL: Uplink

[0109]

[0110] *- ZP: zero power

[0111] FIG. 1 illustrates an exemplary flexible network topology to which some of the examples of the present specification may be applied.

[0112] To compensate for incomplete areas of network coverage, a network topology in which the Split Radio Access Network (RAN) is configured more flexibly and resiliently may be considered. To this end, various nodes such as IAB nodes, relays, and RF repeaters, as exemplified in Fig. 1, may be applied, and NTN may be integrated. For example, an IAB node may correspond to a node that provides wireless backhaul. For example, a relay may refer to any intermediate point, and in the case of a sidelink relay where a terminal functions as a relay, it may collectively refer to a terminal-to-network (U2N) relay and a terminal-to-terminal (U2U) relay. For example, an RF repeater may correspond to a node that performs simple signal amplification and forwarding functions, and in the case of a network-controlled repeater, it may adjust transmit / receive settings based on information provided by the network as well as signal amplification and forwarding. For example, an NTN node may correspond to a satellite or aircraft that provides NTN coverage that is difficult for a terrestrial network to provide. In addition to these examples, various intermediate points can be introduced to improve network topology.

[0113] Referring to FIG. 1, a split RAN can support the division of a base station into one centralized unit (CU) and one or more distributed units (DU). The CU and DU may correspond to logical units. The CU may be further divided into a control plane (CP) portion and one or more user plane (UP) portions. Since a failure in the CU-CP affects not only the CU-UP but also the DU, various intermediate points may be introduced to compensate for this.

[0114] An intermediate point may correspond to a terminal or a base station depending on its relative relationship with other nodes. For example, an IAB node may include a mobile-termination (MT) portion and a DU. The MT can connect the IAB node to a donor node. The DU of the IAB node may serve other terminals or connect to other IAB nodes to provide multi-hop wireless backhaul to terminals. In other words, an IAB node may correspond to a base station in its relative relationship with user-side nodes and to a terminal in its relative relationship with network-side nodes.

[0115] In some examples of this specification, the description of a terminal may apply equally to an intermediate point corresponding to a terminal in relation to a network-side endpoint as well as to a user-side endpoint. Similarly, in some examples of this specification, the description of a base station may apply equally to an intermediate point corresponding to a base station in relation to a user-side endpoint as well as to a network-side endpoint. However, in most cases where there is no additional description of the operation of three or more entities, the communication entities in this specification are briefly described by the term terminal and / or base station (or first node and / or second node), wherein the term terminal and / or base station (or first node and / or second node) is interpreted to include or replace any endpoint or any intermediate point in relation to other nodes.

[0116] That is, for the sake of brevity of description in some examples of this specification, the subject of the operation may be referred to as a base station and / or terminal (or a first node and / or a second node). Additionally, the term base station and / or terminal (or a first node and / or a second node) may be interpreted or substituted as in the following examples: for example, the base station (or the first node) and the terminal (or the second node) may correspond to a first endpoint and a second endpoint, respectively; may correspond to an endpoint and an intermediate point, respectively; may correspond to an intermediate point and an endpoint, respectively; or may correspond to a first intermediate point and a second intermediate point, respectively.

[0117] In this specification, there may be no intermediate points between the base station and the terminal, or there may be one or more. If intermediate points exist, the intermediate points may correspond to IAB nodes, relays, RF repeaters, NTN (non-terrestrial network) nodes, or nodes supporting other functions. The intermediate points may be nodes with a fixed location or nodes with an indefinite location.

[0118] FIG. 2 illustrates a communication system applicable to the present disclosure.

[0119] The communication system (100) of FIG. 2 includes a wireless device (110), a network device (120), and a network (130). Here, the wireless device (110) refers to a device that performs communication using wireless access technology (e.g., LTE, LTE-A, LTE-A pro, NR, 5G, 5G-A, 6G) and may be referred to as a communication / wireless / 5G / 6G device. Although not limited thereto, the wireless device (110) may include a robot (110a), a vehicle (110b-1, 110b-2), an XR (extended reality) device (110c), a hand-held device (110d), a home appliance (110e), an IoT (Internet of Thing) device (110f), and an AI (artificial intelligence) device / server (110g). For example, the vehicle may include a vehicle equipped with wireless communication capabilities, an autonomous vehicle, a vehicle capable of performing inter-vehicle communication, etc. Here, the vehicle (110b-1, 110b-2) may include an unmanned aerial vehicle (UAV) (e.g., a drone). The XR device (110c) includes an augmented reality (AR) / virtual reality (VR) / mixed reality (MR) device and may be implemented in the form of a head-mounted device (HMD), a head-up display (HUD) equipped in a vehicle, a television, a smartphone, a computer, a wearable device, a home appliance, digital signage, a vehicle, a robot, etc. The portable device (110d) may include a smartphone, a smartpad, a wearable device (e.g., a smartwatch, smart glasses), a computer (e.g., a laptop, etc.). The home appliance (110e) may include a TV, a refrigerator, a washing machine, etc. The IoT device (110f) may include a sensor, a smart meter, etc. The wireless device (110) may correspond to a terminal (or first node) or an intermediate point.The network device (120) may correspond to a base station (or a second node) or another intermediate point. For example, the network device (120) may also be implemented as a wireless device (110), and a specific wireless device (120a) may operate as a network device (120) to another wireless device (110).

[0120] Wireless devices (110a to 110f) can be connected to a network (130) through a network device (120). AI technology may be applied to the wireless devices (110a to 110f), and the wireless devices (110a to 110f) can be connected to an AI server (110g) through the network (130). The network (130) can be configured using a 3G network, a 4G (e.g., LTE) network, a 5G (e.g., NR) network, or a 6G network. The wireless devices (110a to 110f) may communicate with each other through the network device (120) / network (130), but may also communicate directly (e.g., sidelink communication) without going through the network device (120) / network (130). For example, vehicles (110b-1, 110b-2) can communicate directly (e.g., V2V (vehicle to vehicle) / V2X (vehicle to everything) communication). Also, an IoT device (110f) (e.g., a sensor) can communicate directly with another IoT device (e.g., a sensor) or other wireless devices (110a to 110f).

[0121] Wireless communication / connection (150a, 150b, 150c) can be established between wireless devices (110a to 110f) / network devices (120) and between network devices (120). Here, wireless communication / connection can be established through various wireless access technologies such as uplink / downlink communication (150a), sidelink communication (150b) (or D2D communication), and communication between network devices (150c) (e.g., relay, IAB (integrated access backhaul)). Through wireless communication / connection (150a, 150b, 150c), wireless devices and network devices / wireless devices, and network devices and network devices can transmit / receive wireless signals to / from each other. For example, wireless communication / connection (150a, 150b, 150c) can transmit / receive signals through various physical channels. To this end, based on the various descriptions of the present disclosure, at least some of the following may be performed: a process for setting various configuration information for transmitting / receiving wireless signals, a process for various signal processing (e.g., channel encoding / decoding, modulation / demodulation, resource mapping / demapping, etc.), a resource allocation process, etc.

[0122] FIG. 3 illustrates an example of a wireless device that can be applied to the present disclosure.

[0123] Referring to FIG. 3, the wireless device (200) can transmit and receive wireless signals through various wireless access technologies (e.g., LTE, LTE-A, LTE-A pro, NR, 5G, 5G-A, 6G). The wireless device (200) includes at least one processor (202) and at least one memory (204), and may additionally include at least one transceiver (206) and / or at least one antenna (208).

[0124] The processor (202) controls the memory (204) and / or the transceiver (206) and may be configured to implement the descriptions, functions, procedures, proposals, methods, and / or sequences of operation disclosed in this document. For example, the processor (202) may process information within the memory (204) to generate a first information / signal and then transmit a wireless signal containing the first information / signal through the transceiver (206). Additionally, the processor (202) may receive a wireless signal containing a second information / signal through the transceiver (206) and then store information obtained from the signal processing of the second information / signal in the memory (204). The memory (204) may be connected to the processor (202) and may store various information related to the operation of the processor (202). For example, memory (204) may store software code containing instructions for performing some or all of the processes controlled by the processor (202) or for performing the descriptions, functions, procedures, proposals, methods, and / or sequences of operations disclosed in this document. Here, the processor (202) and memory (204) may be part of a communication modem / circuit / chip designed to implement wireless communication technology. A transceiver (206) may be connected to the processor (202) and may transmit and / or receive wireless signals through at least one antenna (208). The transceiver (206) may include a transmitter and / or receiver. The transceiver (206) may be interchangeable with a radio frequency (RF) unit. In this disclosure, a wireless device may mean a communication modem / circuit / chip.

[0125] Hereinafter, hardware elements of the wireless device (200) will be described in more detail. Although not limited thereto, at least one protocol layer may be implemented by at least one processor (202). For example, at least one processor (202) may implement at least one layer (e.g., functional layers such as PHY (physical), MAC (media access control), RLC (radio link control), PDCP (packet data convergence protocol), RRC (radio resource control), and SDAP (service data adaptation protocol). At least one processor (202) may generate at least one PDU (Protocol Data Unit) and / or at least one SDU (service data unit) according to the descriptions, functions, procedures, proposals, methods and / or operation sequences disclosed in this document. At least one processor (202) may generate messages, control information, data, or information according to the descriptions, functions, procedures, proposals, methods and / or operation sequences disclosed in this document. At least one processor (202) may generate a signal (e.g., baseband signal) including a PDU, SDU, message, control information, data, or information according to the functions, procedures, proposals, and / or methods disclosed in this document and provide it to at least one transceiver (206). At least one processor (202) may receive a signal (e.g., baseband signal) from at least one transceiver (206) and may obtain a PDU, SDU, message, control information, data, or information according to the descriptions, functions, procedures, proposals, methods, and / or operation sequences disclosed in this document.

[0126] At least one processor (202) may be referred to as a controller, microcontroller, microprocessor, or microcomputer. At least one processor (202) may be implemented by hardware, firmware, software, or a combination thereof. For example, at least one application-specific integrated circuit (ASIC), at least one digital signal processor (DSP), at least one digital signal processing device (DSPD), at least one programmable logic device (PLD), or at least one field programmable gate array (FPGA) may be included in at least one processor (202). The descriptions, functions, procedures, proposals, methods, and / or operation sequences disclosed in this document may be implemented using firmware or software, and the firmware or software may be implemented to include modules, procedures, functions, etc. Firmware or software configured to perform the descriptions, functions, procedures, proposals, methods, and / or operation sequences disclosed in this document may be included in at least one processor (202) or stored in at least one memory (204) and driven by at least one processor (202). The descriptions, functions, procedures, proposals, methods, and / or flowcharts disclosed in this document may be implemented using firmware or software in the form of code, instructions, and / or sets of instructions.

[0127] At least one memory (204) may be connected to at least one processor (202) and may store various forms of data, signals, messages, information, programs, codes, instructions, and / or commands. At least one memory (204) may be composed of ROM (read-only memory), RAM (random access memory), EPROM (erasable programmable read-only memory), flash memory, hard drive, registers, cache memory, computer read storage media, and / or combinations thereof. At least one memory (204) may be located inside and / or outside of at least one processor (202). Additionally, at least one memory (204) may be connected to at least one processor (202) via various technologies, such as wired or wireless connections.

[0128] At least one transceiver (206) may transmit user data, control information, wireless signals / channels, etc., as mentioned in the methods and / or operation flowcharts, etc. of this document to at least one other device. At least one transceiver (206) may receive user data, control information, wireless signals / channels, etc., as mentioned in the descriptions, functions, procedures, proposals, methods and / or operation flowcharts, etc. disclosed in this document from at least one other device. For example, at least one transceiver (206) may be connected to at least one processor (202) and may transmit and receive wireless signals. For example, at least one processor (202) may control at least one transceiver (206) to transmit user data, control information, or wireless signals to at least one other device. Additionally, at least one processor (202) may control at least one transceiver (206) to receive user data, control information, or wireless signals from at least one other device. Additionally, at least one transceiver (206) may be connected to at least one antenna (208), and at least one transceiver (206) may be configured to transmit and receive user data, control information, wireless signals / channels, etc., as described in the descriptions, functions, procedures, proposals, methods, and / or operation sequence diagrams disclosed in this document through at least one antenna (208). In this document, at least one antenna may be a plurality of physical antennas or a plurality of logical antennas (e.g., antenna ports). At least one transceiver (206) may convert the received wireless signals / channels, etc., from RF band signals to baseband signals in order to process the received user data, control information, wireless signals / channels, etc., using at least one processor (202). At least one transceiver (206) may convert the processed user data, control information, wireless signals / channels, etc., from baseband signals to RF band signals using at least one processor (202).To this end, at least one transceiver (206) may include an (analog) oscillator and / or filter.

[0129] The components of the wireless device described with reference to FIG. 3 may be referred to by other terms in terms of their function. For example, the processor (202) may be referred to as the control unit, the transceiver (206) as the communication unit, and the memory (204) as the storage unit. In some cases, the communication unit may be used to mean at least a part of the processor (202) and the transceiver (206).

[0130] The structure of the wireless device described with reference to FIG. 3 can be understood as the structure of at least part of various devices. For example, the structure of the wireless device illustrated in FIG. 3 may be at least part of the various devices described with reference to FIG. 2 (e.g., robot (110a), vehicle (110b-1, 110b-2), XR device (110c), portable device (110d), home appliance (110e), IoT device (110f), AI device / server (110g)). Furthermore, according to various embodiments, the device may include other components in addition to the components illustrated in FIG. 3.

[0131] For example, the device may be a portable device such as a smartphone, smartpad, wearable device (e.g., smart watch, smart glasses), or portable computer (e.g., laptop, etc.). In this case, the device may further include at least one of a power supply unit that supplies power and includes a wired / wireless charging circuit, a battery, etc., an interface unit that includes at least one port for connection with another device (e.g., audio input / output port, video input / output port), and an input / output unit for inputting and outputting video information / signals, audio information / signals, data, and / or information input by a user.

[0132] For example, the device may be a mobile device such as a mobile robot, vehicle, train, manned / unmanned aerial vehicle (AV), or ship. In this case, the device may further include at least one of a drive unit comprising at least one of an engine, motor, power train, wheel, brake, and steering device of the device; a power supply unit that supplies power and includes a wired / wireless charging circuit, battery, etc.; a sensor unit that senses state information, environmental information, and user information of the device or its surroundings; an autonomous driving unit that performs functions such as path maintenance, speed control, and destination setting; and a position measurement unit that acquires position information of the moving body through a GPS (global positioning system) and various sensors.

[0133] For example, the device may be an XR device such as an HMD, a HUD (head-up display) equipped in a vehicle, a television, a smartphone, a computer, a wearable device, a home appliance, digital signage, a vehicle, a robot, etc. In this case, the device may further include at least one of a power supply unit that supplies power and includes a wired / wireless charging circuit, a battery, etc., an input / output unit that acquires control information, data, etc. from the outside and outputs a generated XR object, and a sensor unit that senses state information, environment information, and user information of the device or the surroundings of the device.

[0134] For example, the device may be a robot that can be classified into industrial, medical, household, military, etc., depending on the purpose or field of use. In this case, the device may further include at least one of a sensor unit that senses state information, environmental information, and user information of the device or its surroundings, and a drive unit that performs various physical actions, such as moving robot joints.

[0135] For example, the device may be an AI device such as a TV, projector, smartphone, PC, laptop, digital broadcasting terminal, tablet PC, wearable device, set-top box (STB), radio, washing machine, refrigerator, digital signage, robot, vehicle, etc. In this case, the device may further include at least one of an input unit that acquires various types of data from the outside, an output unit that generates output related to sight, hearing, or touch, a sensor unit that senses state information, environmental information, and user information of the device or its surroundings, and a training unit that learns a model composed of an artificial neural network using training data.

[0136] The structure of the wireless device exemplified in FIG. 3 may be understood as part of a terminal (or first node), or part of an intermediate point, or part of a base station (or second node). If the device exemplified in FIG. 3 is a base station (or second node), the device may further include a wired transceiver for front haul and / or back haul communication. However, if the front haul and / or back haul communication is based on wireless communication, at least one transceiver (206) exemplified in FIG. 3 is used for front haul and / or back haul communication, and the wired transceiver may not be included.

[0137] FIG. 4 illustrates a communication procedure between a first node (e.g., a terminal) and a second node (e.g., a base station) applicable to the present disclosure.

[0138] The second node of FIG. 4 supports dynamic spectrum sharing (DSS) and can provide connectivity to both nodes where 6G technology is implemented and nodes where pre-6G wireless communication technology (e.g., 5G, 4G) is implemented. That is, the first node of FIG. 4 may have 6G technology implemented or pre-6G wireless communication technology (e.g., 5G, 4G) implemented. Additionally, the first node and / or the second node may support full duplex mode as well as non-overlapping full duplex mode.

[0139] In FIG. 4, for the sake of simplicity of explanation, the first node and the second node are assumed to be a terminal and a base station, respectively, and the operation of the terminal (110) and the base station (120) transmitting and / or receiving data, and the operation performed prior to this, are illustrated. However, the operation of FIG. 4 is not limited to the operation between the terminal and the base station, but can be interpreted as the operation between the first node and the second node. Additionally, FIG. 4 illustrates the operation of direct transmission and reception of wireless signals between the terminal (110) and the base station (120), but there may be one or more intermediate points between the terminal (110) and the base station (120), and wireless signals may be transmitted and received via one or more intermediate points.

[0140] Referring to FIG. 4, the terminal (110) and the base station (120) can perform synchronization (401). For example, the terminal (110) performs an initial cell search operation. Specifically, the terminal (110) can detect a synchronization signal for at least one base station connection transmitted from the base station (120) according to a predefined rule. Here, the synchronization signal may include a plurality of synchronization signals classified according to structure or use (e.g., a first synchronization signal (e.g., a primary synchronization signal), a second synchronization signal (e.g., a secondary synchronization signal), etc.). Through this, the terminal (110) can identify the boundary of the unit (e.g., frame, subframe, slot and / or symbol) constituting the wireless signal transmission of the base station (120) and obtain information about the base station (120) (e.g., cell identifier).

[0141] The terminal (110) can obtain system information transmitted from the base station (120) (403). The system information is information related to the attributes, characteristics, and / or capabilities of the base station (120) required to connect to the base station (120) and use the service, and can be classified according to content (e.g., whether it is essential for connection), transmission structure (e.g., channel used, whether it is provided on-demand), etc., and can be classified, for example, into first system information (e.g., MIB (master information block), primary system information), second system information (e.g., SIB (system information block), secondary system information), etc. If necessary, the terminal (110) may transmit a signal requesting system information prior to receiving the system information. However, the request and provision of system information may be performed after the random access procedure described later.

[0142] A terminal (110) and a base station (120) can perform a random access procedure (405). The terminal (110) can transmit and / or receive at least one message for a random access procedure (e.g., random access preamble, RAR (random access response) message, etc.) based on information related to the channel for the random access procedure of the base station (120) obtained through system information (e.g., channel location, channel structure, structure of supported preamble, etc.). For example, the terminal (110) can transmit a first message (e.g., preamble, MSG1) through the channel for the random access procedure, receive a second message (e.g., RAR message, MSG2), transmit a third message (e.g., MSG3) containing information related to the terminal (110) (e.g., identification information) to the base station (120) using scheduling information included in the second message, and receive a fourth message (e.g., MSG4) for contention resolution and / or connection establishment. As another example, the first message and the third message can be transmitted and received as a single message, or the second message and the fourth message can be transmitted and received as a single message.

[0143] The terminal (110) and the base station (120) can perform signaling of control information (407). Here, the control information can be defined in various layers, such as a layer that controls the connection (e.g., a radio resource control (RRC) layer), a layer that handles mapping between logical channels and transmission channels (e.g., a media access control (MAC) layer), and a layer that handles physical channels (e.g., a physical (PHY) layer). For example, the terminal (110) and the base station (120) can perform at least one of signaling to establish a connection, signaling to determine settings related to communication, and signaling to indicate allocated resources.

[0144] The terminal (110) and the base station (120) can transmit and / or receive data (409). In other words, the terminal (110) and the base station (120) can process data based on the signaling of control information and transmit and / or receive data. For example, when transmitting data, the terminal (110) or the base station (120) can perform at least one of channel encoding, rate matching, scrambling, constellation mapping, layer mapping, waveform modulation, antenna mapping, and resource mapping on the information bits. Conversely, when receiving data, the terminal (110) or the base station (120) can perform at least one of signal extraction from resources, antenna-specific waveform demodulation, signal placement considering layer mapping, constellation demapping, descrambling, and channel decoding.

[0145] 6G System Core Technology

[0146] The 6G (wireless communication) system aims for (i) very high data rates per device, (ii) a very large number of connected devices, (iii) global connectivity, (iv) very low latency, (v) reduced energy consumption of battery-free IoT (internet of things) devices, (vi) ultra-reliable connectivity, and (vii) connected intelligence with machine learning capabilities. The vision of the 6G system can be four aspects: intelligent connectivity, deep connectivity, holographic connectivity, and ubiquitous connectivity.

[0147] As core implementation technologies for 6G systems, technologies such as artificial intelligence (AI), THz (Terahertz) communication, optical wireless technology, FSO backhaul network, massive MIMO technology, blockchain, 3D networking, quantum communication, unmanned aerial vehicles, cell-free communication, wireless information and energy transfer (WIET), integration of sensing and communication, integration of access backhaul networks, holographic beamforming, big data analysis, and large intelligent surface (LIS) can be adopted.

[0148] artificial intelligence

[0149] The introduction of AI into communications can streamline and enhance real-time data transmission. AI can determine how complex target tasks are performed using numerous analyses. In other words, AI can increase efficiency and reduce processing latency. Time-consuming tasks such as handover, network selection, and resource scheduling can be performed instantly using AI. AI can also play a significant role in M2M, machine-to-human, and human-to-machine communication. Furthermore, AI can enable rapid communication in Brain-Computer Interfaces (BCI). AI-based communication systems can be supported by metamaterials, intelligent structures, intelligent networks, intelligent devices, intelligent cognitive radios, self-sustaining wireless networks, and machine learning.

[0150] The following describes a functional framework for AI / ML operations.

[0151] Below, to provide a more specific explanation of AI (or AI / ML), terms may be defined as follows.

[0152] - Data collection: Data collected from network nodes, management entities, or terminals, serving as a basis for AI model training, data analysis, and inference.

[0153] - AI Model: A data-driven algorithm that applies AI technology to generate a set of outputs containing predictive information and / or decision parameters based on a set of inputs.

[0154] - AI / ML Training: An online or offline process of training an AI model by learning features and patterns that best represent data and acquire an AI / ML model trained for inference.

[0155] - AI / ML Inference: A process of making predictions or deriving decisions based on collected data and AI models using trained AI models.

[0156] Life Cycle Management (LCM) procedures for AI / ML models (i.e., model training, model deployment, model inference, model monitoring, model updating, etc.) can be classified into functionality-based LCM and model-based LCM. In functionality-based LCM, AI / ML models may not be identifiable within the network, and the network can direct the activation, deactivation, fallback, or switching of AI / ML functionality. In model-ID (identifier)-based LCM, AI / ML models can be identified within the network, and the network or terminal can activate, deactivate, select, or switch AI / ML models via the model ID.

[0157] Figure 5 illustrates a general functional architecture for an AI / ML model.

[0158] In particular, Figure 5 illustrates a general functional architecture related to both Functionality-based LCM and Model-based LCM. Some functions or some data / information / command flows (i.e., arrows) illustrated in Figure 5 may be omitted.

[0159] Referring to FIG. 5, a general functional framework may be configured to include a data collection function (10), a model training function (20), a management function (30), an inference function (40), and a model storage function (50).

[0160] The Data Collection function (10) is a function that provides input data to the Model Training function (20), Management function (30), and Inference function (40). The Data Collection function (10) performs data preparation based on raw data and can provide input data processed through data preparation. Examples of raw data may include received data / measurement data from terminals or other network entities, inference / output of AI / ML models, etc. The Data Collection function (10) may be performed by a single entity (e.g., terminal, network node, etc.) but may also be performed by multiple entities.

[0161] Here, training data (11) refers to data required as input for the AI / ML model training function (20). monitoring data (12) refers to data required as input for the management (30) of the AI / ML model or AI / ML function. inference data (13) refers to data required as input for the AI / ML inference function (30).

[0162] The Model Training function (20) is a function that performs AI / ML model training, validation, and testing, which can generate model performance metrics that can be used as part of the AI / ML model testing procedure. If necessary, the Model Training function (20) can perform data preparation (e.g., data pre-processing and cleaning, forming and transformation) based on the Training Data (11) delivered from the Data Collection function (10).

[0163] Trained / Updated Model (21): If there is a Model Storage function (50), it is used to transfer trained, validated, and tested AI / ML models to the Model Storage function (50) or to transfer updated versions of the models to the Model Storage function (50).

[0164] The Management function (30) is a function that supervises the operation of an AI / ML model or an AI / ML function. Additionally, the Management function (30) may make decisions to ensure appropriate inference operations based on data received from the Data Collection function (10) (i.e., Monitoring Data (12)) and / or data received from the Inference function (40) (i.e., Inference Output (41)).

[0165] Management Instruction (32) is information required as input to manage the Inference function (40). The relevant information may include the selection / (de)activation / switching of an AI / ML model or an AI / ML-based function, and may also include a fallback to a non-AI / ML operation (i.e., not relying on the inference process).

[0166] A Model Transfer / Delivery Request (33) can be used to request model(s) from Model Storage (50).

[0167] Performance Feedback / Retraining Request (31) refers to information required as input to Model Training function (20) (e.g., for the purpose of retraining or updating the model).

[0168] The inference function (40) is a function that provides output from the process of applying an AI / ML model or AI / ML function using data (i.e., inference data (13)) provided by the data collection (10) as input. Data preparation (e.g., data preprocessing and cleaning, formatting and transformation) may also be performed based on the inference data (13) delivered by the data collection (10). If necessary, the inference function (40) may also perform data preparation (e.g., data pre-processing and cleaning, forming and transformation) based on the inference data (13) provided by the data collection function (10).

[0169] Inference Output (41) is data used in the Management function (30) to monitor the performance of an AI / ML model or AI / ML function. Inference Output (41) may include the inference output of an AI / ML model generated by the Inference function (30), and the details of the inference output may vary depending on the use case.

[0170] The Model Storage function (50) is a function that stores a trained / updated model that can be used to perform the Inference function (40). The Model Storage function (50) exemplified in FIG. 5 can be used as a reference point (if any) applicable to protocol termination, model transmission / delivery, and related processes. Additionally, the Model Storage function (50) is an example and is not intended to restrict the storage location of the actual AI / ML model, and may be omitted.

[0171] Model Transfer / Delivery (51) is used to transfer an AI / ML model to an inference function.

[0172] Cooperation levels can be defined as follows based on the capability of AI / ML functions among multiple nodes, and variations resulting from the combination of multiple levels or the separation of any one level are also possible.

[0173] Cat 0a) No collaboration framework: AI / ML algorithms are based on pure implementation and do not require changes to the wireless interface.

[0174] Cat 0b) This level corresponds to a framework that involves a wireless interface modified to fit efficient implementation-based AI / ML algorithms but without cooperation.

[0175] Cat 1) Inter-node support is involved to improve the AI / ML algorithms of each node. For example, this applies when a specific node receives support from other nodes (for training, adaptation, etc.) and vice versa. At this level, model exchange between network nodes is not required.

[0176] Cat 2) Collaborative AI / ML tasks can be performed among multiple nodes. This level requires the exchange of AI / ML model commands or network nodes.

[0177] FIG. 5 is a diagram illustrating an overall functional framework for an AI / ML model, and all functions and / or all data / information / command signals illustrated in FIG. 5 may not be performed within a specific node, and only some may be performed.

[0178] AI / ML models can be classified into one-side models and two-side models depending on whether training and / or inference are performed on a single node or jointly / sequentially on multiple nodes.

[0179] A one-side model can refer to an AI / ML model where inference is performed entirely by a single node (e.g., a terminal or a network). Here, the training of the AI / ML model can also be performed entirely by a single node. The training and inference of the AI / ML model may be performed by the same node, or they may be performed by different nodes.

[0180] A two-side model can refer to an AI / ML model in which joint inference is performed across multiple nodes (e.g., terminals and networks). Joint inference means that inference is performed collaboratively across multiple nodes; for example, the first part of the inference may be performed by the first node, and the remainder by the second node. Two-side models can be classified into various types as follows, depending on the training method of the AI / ML model.

[0181] - First type: An AI / ML model can be trained on a single node. In this case, joint training can be performed. The trained model can then be distributed to other nodes / entities.

[0182] - Second type: Joint training of AI / ML models can be performed on multiple nodes / entities (e.g., networks and terminals). Joint training can mean that model generation (e.g., CSI generation) and model reconstruction (CSI compression by sub-use cases) are trained in the same loop for forward activation and backward gradient. In this type, joint training can include both simultaneous training (i.e., model generation training and model reconstruction training are performed simultaneously) and sequential training (i.e., model reconstruction training is performed after model generation training).

[0183] - Third Type: Separate training of AI / ML models can be performed at multiple nodes (e.g., networks and terminals). Separate training may mean that training starts sequentially at one node and continues at another node. In this case, if the first node performs the AI / ML model first and shares the training data with the second node, the second node can perform the AI / ML model using the shared training data. For example, training for the CSI generation part may be performed by the terminal, while CSI reconstruction may be performed by the network.

[0184] FIG. 6 illustrates a communication procedure between a first node (e.g., terminal) and a second node (e.g., base station) to which an AI / ML model is applied.

[0185] The operations described below may be explained / interpreted based on an AI / ML model as shown in FIG. 6 below, even without separate mention (i.e., without explicit mention of being by / based on / for an AI / ML model). Furthermore, unless specifically limited, the AI / ML model may correspond to a one-side model in which inference is performed entirely by a single node or a two-side model in which joint inference is performed by multiple nodes.

[0186] First signaling (601): In the following description, the signaling (e.g., information / data / channel / signal, etc.) or set of signaling between a specific node (e.g., terminal, network, etc.) and another node may be interpreted as the signaling or set of signaling of the first signaling (601) used to perform an operation based on an AI / ML model, even if not otherwise mentioned. For example, it may correspond to training data for training (i.e., creation and / or reconstruction) of the AI / ML model of FIG. 5, or to inference data used for inference of the AI / ML model, or to feedback for the AI / ML model. If, in this specification, signaling between nodes is not required prior to an operation based on an AI / ML model, the first signaling (601) may be omitted. In this specification, if a one-side model is used, the unidirectional / bidirectional signaling (set) in this specification may correspond to the signaling of the first signaling (601). Additionally, when a two-side model is used in the present specification, unidirectional / bidirectional signaling in the present specification may correspond to the first signaling (601), and repetitive signaling operation may also correspond to the first signaling (601).

[0187] For example, in AI / ML model-based beam management, when a base station predicts (i.e., infers) high-quality beam(s) based on an AI / ML model, the base station can receive quality / intensity information for multiple beams from the terminal. Additionally, when a terminal predicts (i.e., infers) high-quality beam(s) based on an AI / ML model, the terminal can receive multiple beams from the base station.

[0188] AI / ML model-based operation (602): In the following description, an operation (e.g., computation, selection, prediction, etc.) at a specific node (e.g., terminal, network, etc.) or a common operation (e.g., computation, selection, prediction, etc.) at multiple nodes (e.g., terminal, network, etc.) may correspond to an AI / ML model-based operation (602) based on one or more functions in the functional framework of the AI / ML model, even without separate mention. For example, it may correspond to the training (i.e., creation and / or reconstruction) of the AI / ML model of FIG. 5 or to the inference of the AI / ML model. When a one-side model is used, an operation performed by a single node in this specification may correspond to an AI / ML model-based operation (602), and when a two-side model is used, a common operation performed by multiple nodes in this specification may correspond to an AI / ML model-based operation (602).

[0189] For example, in an AI / ML model-based BM, a base station can predict (i.e., infer) high-quality beam(s) based on an AI / ML model by using quality / intensity information for multiple beams received from a terminal as inference data. Additionally, a terminal can measure multiple beams received from a base station and predict (i.e., infer) high-quality beam(s) based on an AI / ML model by using the measurement results as inference data.

[0190] Second signaling (603): In the following description, signaling (e.g., information / data / channel / signal, etc.) or a set of signaling between a specific node (e.g., terminal, network, etc.) and another node may be interpreted as the second signaling (603) or a set of signaling generated as a result of an operation based on an AI / ML model, even without separate mention. For example, it may correspond to the output resulting from the inference of the AI / ML model of FIG. 5. If signaling between nodes is not required as a result of an operation based on an AI / ML model in this specification, the second signaling (603) may be omitted. If a one-side model is used in this specification, the unidirectional / bidirectional signaling (set) in this specification may correspond to the second signaling (603). Additionally, when a two-side model is used in this specification, unidirectional / bidirectional signaling in this specification may correspond to the second signaling (603), and repetitive signaling operation may also correspond to the second signaling (603).

[0191] For example, in an AI / ML model-based BM, the base station may transmit beam(s) predicted based on the AI / ML model as candidates to the terminal so that the terminal can determine the optimal beam. Additionally, the terminal may report the beam(s) predicted based on the AI / ML model to the base station to request the base station to transmit candidate beams as candidates for determining the optimal beam.

[0192] THz communication

[0193] Data transmission rates can be increased by expanding bandwidth. This can be achieved by using sub-THz communication with wide bandwidth and applying advanced large-scale MIMO technology. THz waves, also known as sub-millimeter radiation, generally refer to a frequency band between 0.1 THz and 10 THz with corresponding wavelengths ranging from 0.03 mm to 3 mm. The 100 GHz–300 GHz band range (Sub-THz band) is considered the primary portion of the THz band for cellular communication. Adding the Sub-THz band to the mmWave band increases 6G cellular communication capacity. Among the defined THz bands, the 300 GHz–3 THz band is located in the far-infrared (IR) frequency band. Although the 300 GHz–3 THz band is part of the broadband, it lies at the boundary of the broadband and immediately following the RF band. Therefore, this 300 GHz–3 THz band exhibits similarities to RF.

[0194] FIG. 7 illustrates an electromagnetic spectrum according to one embodiment of the present disclosure. The embodiment of FIG. 7 may be combined with various embodiments of the present disclosure. Key characteristics of THz communication include (i) a widely available bandwidth to support very high data transmission rates, and (ii) high path loss occurring at high frequencies (highly directional antennas are indispensable). The narrow beam width generated by highly directional antennas reduces interference. The small wavelength of THz signals allows a much larger number of antenna elements to be integrated into devices and BSs operating in this band. This enables the use of advanced adaptive array techniques that can overcome range limitations.

[0195] Transmitting system information (i.e., information related to the attributes, characteristics, and / or capabilities of the BS required to use the service, etc.) (e.g., MIB, SIB, etc.) in the THz frequency band can be inefficient because, in the case of high frequency bands, beam sweeping must be performed more frequently to cover the entire area of ​​the cell as the beam width becomes narrow. In particular, transmitting system information in this manner is even more inefficient when there are not many users in the cell. Accordingly, a system information transmission procedure as shown in FIG. 8 below may be used.

[0196] FIG. 8 illustrates an example of a procedure for transmitting system information for THz communication to which the present disclosure applies. Although this example is written with THz conditions in mind, it is also applicable to 6G communication environments where THz is not applied. Furthermore, the procedure exemplified in FIG. 8 can be combined with various embodiments of the present disclosure described below. For example, the embodiments described below may be performed based on the system information obtained by the procedure exemplified in FIG. 8.

[0197] Referring to FIG. 8, the base station can transmit system information of cell #1 through cell #2 (801). That is, the base station provides at least two cells, cell #1 uses the THz frequency band, and cell #2 uses a frequency band other than the THz frequency band. Here, the system information may include at least one information / state / parameter / setting generated at the higher layer and the physical layer, respectively. For example, at least one information / state / parameter / setting generated at the higher layer may include at least one of SFN, control information setting for SIB1 (e.g., PDCCH configuration for SIB1, etc.), information related to cell selection / entry (e.g., cell barring, cell re-selection, etc.), and subcarrier spacing, and at least one information / state / parameter / setting generated at the physical layer may include at least one of SFN, half frame indicator, and SSB index. However, this is merely an example, and system information may include information, status, parameters, and settings related to Cell #1 / Cell #2 generated at various types of physical layers / upper layers. To this end, as an example, Cell #1 and Cell #2 may have a secondary cell and primary cell relationship.

[0198] The UE can obtain synchronization for cell #1 (803). Synchronization can be obtained by detecting a synchronization signal. Generally, synchronization is obtained prior to receiving system information, but since the system information for cell #1 is received in cell #2, synchronization for cell #1 can be obtained after receiving system information. For example, the UE can obtain synchronization based on system information. However, unlike FIG. 8, synchronization may be obtained before step 801 according to other examples.

[0199] The UE can transmit a signal to connect to Cell #1 (805). For example, the signal may include information for connecting to Cell #1 (e.g., a random access preamble). The structure of the signal and the resources for transmitting the signal (e.g., a channel) can be identified through system information. Subsequently, the UE and the base station can perform a connection procedure to Cell #1 and perform communication (807). In this process, operations according to various embodiments described below may be performed.

[0200] The procedure described with reference to FIG. 8 may be performed when the UE (801) first connects to cell #1 of the base station. Alternatively, a similar procedure may be performed when the UE (801) handovers to cell #1 of the base station. However, in the case of a handover, the system information of cell #1 may be received from a cell of a different base station rather than cell #2 of the base station.

[0201] Communication in the THz band is expected to experience severe path loss, and to overcome this, terminals and base stations must use very sharp beams. The use of sharp beams means that terminals and base stations must perform beam control along with beamforming, and the number of beams used becomes very large. Therefore, it takes a very long time to align the transmit and receive beams between the base station and the terminal. In addition, if the beam alignment between the base station and the terminal is misaligned due to the movement of the terminal, time is frequently required to realign the beams, which may result in an unstable link. Accordingly, a beam management procedure as shown in Fig. 9 below may be used.

[0202] FIG. 9 illustrates a beam management procedure applicable to the present disclosure. FIG. 9 illustrates an example of a procedure for searching and / or selecting beams for THz communication, but is not limited to a THz environment and is applicable to a 6G communication environment. Additionally, the procedure exemplified in FIG. 9 may be combined with various embodiments of the present disclosure described below. Here, a beam may be interpreted as 'spatial (configuration) information', 'spatial domain filter', 'spatial domain transmit filter', 'spatial domain receive filter', or / and a term having an equivalent technical meaning capable of distinguishing a beam (e.g., Reference signal, SSB (Synchronization Signal Block) Index, TRP (transmission reception point), panel, cell, TP (transmission point), base station, control resource-related information (e.g., CORESET (control resource set)-related information, etc.).

[0203] Referring to FIG. 9, the base station can configure resources for beam management (901). Here, the resources may include at least one of time-frequency resources, channels, and spatial resources (e.g., antenna ports). For example, the base station may utilize a beam search signal (BSS) that is spatially separated from existing downlink signals / channels for beam search. Here, the BSS may be transmitted based on a dedicated port for beam search. The dedicated port may be a port different from the port for transmitting existing downlink signals / channels (e.g., synchronization signals (e.g., SSB, etc.), data channels (e.g., PDSCH, etc.)). BSS is a term defined for convenience of explanation, and the technical concept according to the present embodiment is not limited to the term BSS itself. That is, a signal transmitted based on a dedicated port defined / configured for beam search may be included in the technical concept according to the present embodiment.

[0204] The base station can transmit measurement signals using multiple transmission beams (903). For example, the measurement signals may include at least one of a reference signal and a synchronization signal. At this time, the measurement signals may be transmitted as many times as the number of beams required for measurement, and may be transmitted using a multi-beam transmission method that forms multiple beams simultaneously to reduce sweeping time. Here, multi-beam transmission may be performed based on at least one of a multi-panel, a sub-array, and a true time delay (TTD).

[0205] The UE can transmit a feedback signal to the base station (905). The feedback signal indicates at least one beam selected by the UE. The UE can select at least one preferred beam based on the received measurement signals. The UE and the base station can perform communication (907). At this time, the UE and the base station can perform communication using the previously selected beam. If channel reciprocity is established, the UE's transmission beam can also be determined through operations 903 and 905, so the UE's transmission can also be performed using the beam selected in operation 905. If channel reciprocity is not established, a procedure including the transmission of the UE's measurement signals and the transmission of the base station's feedback signal may be performed first to determine the UE's transmission beam. In operation 907, operations according to various embodiments described below may be performed.

[0206] Integrated Sensing and Communication (ISAC)

[0207] Wireless sensing is a technology that utilizes radio frequencies to determine the instantaneous linear velocity, angle, and distance (range) of an object, thereby obtaining information about the characteristics of the environment and / or objects within that environment. Since radio frequency sensing capabilities do not require connecting to objects via devices within a network, they can provide services for determining object locations without the need for devices. The ability to obtain range, velocity, and angle information from radio frequency signals can provide a wide range of new functions, such as various object detection, object recognition (e.g., vehicles, humans, animals, UAVs), and high-precision localization, tracking, and activity recognition. Wireless sensing services can provide information to various industries (e.g., unmanned aerial vehicles, smart homes, V2X, factories, railways, public safety, etc.) that enable applications such as intruder detection, assisted vehicle steering and navigation, trajectory tracking, collision avoidance, traffic management, and health and traffic management. In some cases, wireless sensing may utilize non-3GPP type sensors (e.g., radar, cameras) to further support 3GPP-based sensing. For example, the operation of a wireless sensing service, that is, the sensing operation, may depend on the transmission, reflection, and scattering processing of wireless sensing signals. Therefore, wireless sensing can provide an opportunity to enhance existing communication systems from communication networks into wireless communication and sensing networks.

[0208] FIG. 10 illustrates an example of a sensing operation according to an embodiment of the present disclosure. The embodiment of FIG. 10 may be combined with various embodiments of the present disclosure. Specifically, FIG. 10(a) illustrates an example of sensing using a sensing receiver and a sensing transmitter located at the same position (e.g., monostatic sensing), and FIG. 10(b) illustrates an example of sensing using a separated sensing receiver and a sensing transmitter (e.g., bistatic sensing).

[0209] For example, in a wireless communication system based on a 6G network of the present specification, referring to FIG. 10(a), the sensing transmitter and the sensing receiver may be configured to be included in a single base station (i.e., the same base station) or a single terminal (i.e., the same terminal). Alternatively, referring to FIG. 10(b), the sensing transmitter and the sensing receiver may be configured to be included in different base stations, in different terminals, or in a terminal and a base station, respectively.

[0210] In this regard, based on whether the sensing transmitter and the sensing receiver are each included in a base station or a terminal, the following six types of sensing modes can be defined.

[0211] - Mode 1: A mode in which the sensing transmitter and sensing receiver are included in a single base station (e.g., base station-based sensing mode in monostatic mode)

[0212] - Second mode: A mode in which the sensing transmitter is included in the first base station and the sensing receiver is included in a second base station different from the first base station (e.g., base station-based sensing mode in bistatic mode)

[0213] - 3rd Mode: A mode in which the sensing transmitter is included in the base station and the sensing receiver is included in the terminal (e.g., base station-terminal sensing mode)

[0214] - 4th Mode: A mode in which the sensing transmitter is included in the terminal and the sensing receiver is included in the base station (e.g., terminal-base station sensing mode)

[0215] - 5th Mode: A mode in which the sensing transmitter and the sensing receiver are contained in a single terminal (e.g., terminal-based sensing mode in monostatic mode)

[0216] - 6th mode: A mode in which the sensing transmitter is included in the first terminal and the sensing receiver is included in a second terminal different from the first terminal (e.g., terminal-based sensing mode in bistatic mode)

[0217] In a wireless communication system based on a 6G network of the present specification, one or more of the six types of sensing modes described above may be utilized independently or in combination.

[0218] In relation to the sensing operation in FIG. 10, the sensing transmitter may transmit a sensing signal for sensing one or more objects (and / or the environment surrounding the objects). For example, the sensing signal may correspond to a radio (frequency) signal defined to be transmittable by a base station / terminal in a wireless communication system based on a 6G network of the present specification. The sensing receiver may receive a signal that is scattered / reflected by one or more objects (and / or the environment surrounding the objects) from the sensing signal transmitted from the sensing transmitter. In the sensing receiver, sensing data may be derived from the scattered / reflected signal, and sensing results may be generated / obtained through processing of the sensing data. Here, the sensing result may include characteristic information (e.g., location, distance, speed, angle, etc.) about one or more objects (and / or the environment surrounding the objects). The sensing result thus generated / acquired may be utilized for wireless sensing services (e.g., detection, tracking, etc. of objects and / or environments) provided by a wireless communication system based on a 6G network of the present specification, or may be provided / disclosed to a trusted third party.

[0219] Additionally, the sensing operation in FIG. 10 is described using a representative example of operation in a wireless communication system based on a 6G network, but it can be extended and applied to cases where terminals / base stations / signals based on previous generations (e.g., 4G, 5G, etc.) networks are utilized.

[0220] Additionally, with respect to the wireless sensing described in this specification, in a wireless communication system based on a 6G network of this specification, time / frequency resources for sensing operations and time / frequency resources for general communication (e.g., UL / DL / sidelink-based communication, etc.) may be scheduled / configured separately.

[0221] FIG. 11 illustrates a time / frequency resource for a sensing operation according to one embodiment of the present specification. The embodiment of FIG. 11 may be combined with various embodiments of the present disclosure.

[0222] Referring to FIG. 11, the time / frequency resources (hereinafter, sensing resources) for the aforementioned sensing operation (e.g., sensing operation based on FIG. 10) can be set / assigned separately from the time / frequency resources (hereinafter, communication resources) for general communication.

[0223] For example, as illustrated in FIG. 11, sensing resources may be configured / assigned in units of symbols in the time domain and / or in units of resource blocks in the frequency domain. Resources other than those configured / assigned to the sensing resources may be utilized as resources for general communication. That is, sensing resources and communication resources may be configured / assigned based on time-division multiplexing (TDM) and / or frequency-division multiplexing (FDM) methods in terms of base station / terminal operation. Additionally or alternatively, unlike that illustrated in FIG. 10, sensing resources may be configured / assigned based on other units in the time domain (e.g., slot, frame, absolute time (ms, us), etc.) and / or other units in the frequency domain (e.g., subcarrier, carrier, absolute frequency (MHz, GHz), etc.).

[0224] Additionally or alternatively, in relation to the setup / allocation / scheduling of resources for general communication described herein, it may be necessary to consider the relationship between said resources and the aforementioned sensing resources. For example, when setting / allocating resources for general communication according to the embodiments of the present disclosure, said resources may be set / allocated to rate-match or puncturing resource areas corresponding to the sensing resources. For example, when scheduling resources for general communication according to the embodiments of the present disclosure, said resources may be scheduled so as not to overlap with resource areas corresponding to the sensing resources. If resources for general communication and resource areas corresponding to the sensing resources are set / allocated / scheduled to overlap according to the embodiments of the present disclosure, either one or both operations may be dropped, skipped, or postponed based on priority, predefined rules, etc. That is, in the embodiments of this specification, resources related to general communication (e.g., resources for signals / channels related to UL / DL / Sidelink-based data / control, etc.) may be configured / assigned / scheduled so as not to overlap with the aforementioned sensing resources.

[0225] Additionally, various channel modeling methods may be applied in relation to the wireless sensing described herein. Channel modeling related to sensing may mean constructing a path for transmitting and receiving sensing signals and / or scattered / reflected signals by considering the object to be sensed and / or the environment to which the object belongs. Since channel modeling may be related to the performance / requirements of sensing in a wireless communication system, it may be an important matter for verifying the validity of the sensing function.

[0226] Channels related to sensing can be classified into channels between an object (e.g., target of interest) and a sensing transmitter / receiver, and channels between the environment to which the object belongs and a sensing transmitter / receiver. In this regard, channel modeling related to sensing can be classified based on the sensing mode (e.g., the six types of modes mentioned above), whether it is an object or an environment, and / or sensing scenarios. For example, channel modeling for a target in a base station / terminal-based monostatic sensing mode, channel modeling for a target in a base station / terminal-based bistatic sensing mode, channel modeling for an environment in a base station / terminal-based monostatic sensing mode, and channel modeling for an environment in a base station / terminal-based bistatic sensing mode can be optimized and configured differently. For example, when various sensing scenarios are classified, they can be divided into channel modeling for detection, location, and tracking scenarios, channel modeling for motion recognition, and channel modeling for imaging / environment reconstruction scenarios. Additionally, channel modeling related to sensing may be based on statistical channel modeling techniques and / or deterministic channel modeling techniques. For example, modeling for sensing in a wireless communication system based on a 6G network of this specification may be based on stochastic geometry channel modeling techniques and / or hybrid with ray tracing channel modeling techniques. Here, the stochastic geometry channel model may be based on various statistical characteristics of the channel state. Furthermore, the hybrid channel model may be based on both ray tracing techniques and stochastic techniques.In the case of a hybrid approach, channels for objects requiring high accuracy and consistency (e.g., targets of interest) can be modeled using ray tracing techniques, while channels for the environment can be modeled using probabilistic techniques.

[0227] FIG. 12 illustrates a procedure related to a sensing operation according to one embodiment of the present specification. The embodiment of FIG. 12 may be combined with various embodiments of the present disclosure.

[0228] For example, in a wireless communication system based on a 6G network of the present specification, in the case of a sensing operation in which a terminal participates, the base station may need to verify (1205) the terminal's capability for the sensing operation. In this regard, the terminal may be configured to report capability information to the base station regarding whether it supports the sensing operation. Additionally, or alternatively, if the terminal is defined in advance in the specification as supporting the sensing operation, the procedure may be omitted. Furthermore, in the case of a sensing operation in which only the base station participates, the base station may be configured to report capability information regarding whether it supports the sensing operation to the entity setting / controlling its sensing operation (e.g., a network entity at the upper level / layer of the base station).

[0229] For example, a base station may perform signaling with a terminal to exchange configuration information related to a sensing operation. For example, the base station may set / instruct the terminal information regarding the mode of the sensing operation (e.g., based on the six types of modes mentioned above), the subject of the sensing operation (e.g., a sensing transmitter, a sensing receiver), the resource of the sensing operation (e.g., a sensing resource as shown in FIG. 11), the target of utilization of the sensing result (e.g., a type of wireless sensing service based on a 6G network, a trusted third party), and channel modeling for sensing (e.g., a channel between the base station / terminal and an object / environment) (1210). For example, the base station may receive such information from a network entity at the upper level / layer of the base station.

[0230] For example, a base station and / or terminal may perform a sensing operation on information set / instructed (1215). For example, the base station and / or terminal may perform procedures such as transmitting a sensing signal as in FIG. 9 described above, receiving scattered / reflected signals, deriving sensing data, obtaining a sensing result through processing the sensing data, and providing the sensing result, as a role of a sensing transmitter and / or sensing receiver. For example, in the operation of the base station / terminal described in this specification, the sensing result provided through the sensing operation may be utilized.

[0231] NR's DL transmission and reception procedure

[0232] The base station can schedule downlink transmissions such as frequency / time resources, the transport layer, downlink precoders, and MCS. The base station can determine the beam for PDSCH transmission.

[0233] The terminal can receive downlink control information (DCI: Downlink Control Information) for downlink scheduling (e.g., including scheduling information of PDSCH) from the base station on the PDCCH.

[0234] DCI formats 1_0, 1_1, or 1_2 may be used for downlink scheduling, and in particular, DCI format 1_1 includes the following information: Identifier for DCI formats, Bandwidth part indicator, Frequency domain resource assignment, Time domain resource assignment, PRB bundling size indicator, Rate matching indicator, ZP CSI-RS trigger, Antenna port(s), Transmission configuration indication (TCI), SRS request, DMRS (Demodulation Reference Signal) sequence initialization

[0235] In particular, the number of DMRS ports can be scheduled according to each state indicated in the antenna port(s) field, and Single-user (SU) / Multi-user (MU) transmission scheduling is also possible.

[0236] In addition, the TCI field consists of 3 bits, and the QCL for the DMRS is dynamically indicated by indicating up to 8 TCI states according to the TCI field value.

[0237] The terminal can receive downlink data from the base station on the PDSCH.

[0238] When the terminal detects a PDCCH containing DCI formats 1_0, 1_1, and 1_2, it decodes the PDCCH according to instructions from the corresponding DCI.

[0239] Here, when the terminal receives a PDSCH scheduled by DCI format 1, the terminal may have a DMRS configuration type set by the upper layer parameter 'dmrs-Type', and the DMRS type is used to receive the PDSCH. Additionally, the terminal may have a maximum number of front-loaded DMRA symbols for the PDSCH set by the upper layer parameter 'maxLength'.

[0240] For DMRS configuration type 1, if a single codeword is scheduled for a terminal and an antenna port mapped to an index of {2, 9, 10, 11 or 30} is assigned, or if a single codeword is scheduled and an antenna port mapped to an index of {2, 9, 10, 11 or 12} or {2, 9, 10, 11, 30 or 31} is assigned, or if two codewords are scheduled for a terminal, the terminal assumes that all remaining orthogonal antenna ports are not associated with PDSCH transmission to another terminal.

[0241] Or, for DMRS configuration type 2, if a single codeword is scheduled for a terminal and an antenna port mapped to an index of {2, 10, or 23} is assigned, or if a single codeword is scheduled and an antenna port mapped to an index of {2, 10, 23, or 24} or {2, 10, 23, or 58} is assigned, or if two codewords are scheduled for a terminal, the terminal assumes that all remaining orthogonal antenna ports are not associated with PDSCH transmission to another terminal.

[0242] When a terminal receives PDSCH, the precoding granularity P' can be assumed to be a consecutive resource block in the frequency domain. Here, P' can be one of the values ​​{2, 4, broadband}.

[0243] If P' is determined to be broadband, the terminal does not expect to be scheduled with non-contiguous PRBs, and the terminal can assume that the same precoding is applied to the allocated resources.

[0244] On the other hand, if P' is determined to be either {2 or 4}, the Precoding Resource Block Group (PRG) is divided into P' consecutive PRBs. The actual number of consecutive PRBs within each PRG may be one or more. The UE may assume that the same precoding is applied to consecutive downlink PRBs within the PRG.

[0245] To determine the modulation order, target code rate, and transport block size within the PDSCH, the terminal first reads the 5-bit MCD field within the DCI and determines the modulation order and target code rate. Then, it reads the redundancy version field within the DCI and determines the redundancy version. Then, the terminal determines the transport block size using the number of layers and the total number of allocated PRBs before rate matching.

[0246] NR's UL transmission and reception procedure

[0247] The base station can schedule uplink transmissions such as frequency / time resources, the transport layer, the uplink precoder, and the MCS. The base station can determine the beam for the terminal's PUSCH transmission.

[0248] The terminal can receive DCI for uplink scheduling (e.g., including scheduling information of PUSCH) from the base station on the PDCCH.

[0249] DCI formats 0_0, 0_1, or 0_2 may be used for uplink scheduling, and in particular, DCI format 0_1 ​​includes the following information: DCI format identifier, UL / SUL (Supplementary uplink) indicator, Bandwidth part indicator, Frequency domain resource assignment, Time domain resource assignment, Frequency hopping flag, Modulation and coding scheme (MCS), SRS resource indicator (SRI), Precoding information and number of layers, Antenna port(s), SRS request, DMRS sequence initialization, UL-SCH (Uplink Shared Channel) indicator

[0250] In particular, the SRS resource indicator field may indicate SRS resources configured within the SRS resource set associated with the upper-level parameter 'usage'. Additionally, 'spatialRelationInfo' can be set for each SRS resource, and its value can be one of {CRI, SSB, SRI}.

[0251] The terminal can transmit uplink data to the base station over PUSCH.

[0252] When the terminal detects a PDCCH containing DCI format 0_0, 0_1, or 0_2, it transmits the corresponding PUSCH according to the instructions given by the DCI.

[0253] For PUSCH transmission, two transmission methods are supported: codebook-based transmission and non-codebook-based transmission:

[0254] i) When the upper layer parameter 'txConfig' is set to 'codebook', the terminal is configured for codebook-based transmission. Conversely, when the upper layer parameter 'txConfig' is set to 'nonCodebook', the terminal is configured for non-codebook-based transmission. If the upper layer parameter 'txConfig' is not set, the terminal does not expect to be scheduled by DCI format 0_1. When PUSCH is scheduled by DCI format 0_0, the PUSCH transmission is based on a single antenna port.

[0255] In the case of codebook-based transmission, PUSCH can be scheduled in DCI format 0_0, DCI format 0_1, DCI format 0_2, or semi-statically. If this PUSCH is scheduled by DCI format 0_1, the terminal determines the PUSCH transmission precoder from the DCI based on SRI, TPMI (Transmit Precoding Matrix Indicator), and transmission rank, as given by the SRS resource indicator field and the Precoding information and number of layers field. TPMI is used to indicate the precoder to be applied across the antenna ports and corresponds to the SRS resource selected by SRI when multiple SRS resources are configured. Or, if a single SRS resource is configured, TPMI is used to indicate the precoder to be applied across the antenna ports and corresponds to that single SRS resource. The transmission precoder is selected from the uplink codebook having the same number of antenna ports as the upper layer parameter 'nrofSRS-Ports'. When the upper layer of the terminal set as 'codebook' is set as the parameter 'txConfig', the terminal is configured with at least one SRS resource. The SRI indicated in slot n is associated with the most recent transmission of the SRS resource identified by the SRI, where the SRS resource precedes the PDCCH (i.e., slot n) carrying the SRI.

[0256] ii) For non-codebook-based transmission, PUSCH may be scheduled in DCI format 0_0, DCI format 0_1, or semi-statically. When multiple SRS resources are configured, the terminal may determine the PUSCH precoder and transmission rank based on the broadband SRI, where the SRI is given by the SRS resource indicator within the DCI or by the upper-layer parameter 'srs-ResourceIndicator'. The terminal utilizes one or multiple SRS resources for SRS transmission, and the number of SRS resources may be configured for simultaneous transmission within the same RB based on UE capabilities. Only one SRS port is configured per SRS resource. Only one SRS resource can be configured with the upper-layer parameter 'usage' set to 'nonCodebook'. The maximum number of SRS resources that can be configured for non-codebook-based uplink transmission is 4. The SRI indicated in slot n is associated with the most recent transmission of the SRS resource identified by the SRI, where the SRS transmission precedes the PDCCH (i.e., slot n) carrying the SRI.

[0257] NR's CSI-related procedures

[0258] The terminal can receive configuration information related to CSI from the base station via RRC signaling. The configuration information related to CSI may include at least one of information related to CSI-IM (interference management) resources, information related to CSI measurement configuration, information related to CSI resource configuration, information related to CSI-RS resources, or information related to CSI report configuration.

[0259] - A CSI-IM resource may be configured for interference measurement (IM) of a terminal. In the time domain, the CSI-IM resource set may be configured periodic, semi-permanent, or non-periodic. The CSI-IM resource may be configured as Zero Power (ZP)-CSI-RS for the terminal. ZP-CSI-RS may be configured separately from Non-Zero Power (NZP)-CSI-RS.

[0260] - UE can assume that the CSI-RS resource(s) for channel measurement set for one CSI reporting and the CSI-IM / NZP CSI-RS resource(s) for interference measurement (when NZP CSI-RS resource(s) are used for interference measurement) have a QCL relationship with respect to 'QCL-TypeD' on a resource-by-resource basis.

[0261] - The CSI resource configuration may include at least one of a CSI-IM resource for interference measurement, an NZP CSI-RS resource for interference measurement, and an NZP CSI-RS resource for channel measurement. The CMR (channel measurement resource) may be an NZP CSI-RS for CSI acquisition, and the IMR (Interference measurement resource) may be an NZP CSI-RS for CSI-IM and IM.

[0262] - CSI-RS may be configured for one or more terminals. Different CSI-RS configurations may be provided for each terminal, or the same CSI-RS configuration may be provided for multiple terminals. CSI-RS may support up to 32 antenna ports. CSI-RS corresponding to N (N is 1 or more) antenna ports may be mapped to N RE positions within a time-frequency unit corresponding to one slot and one RB. If N is 2 or more, N-port CSI-RS may be multiplexed using CDM, FDM, and / or TDM methods. CSI-RS may be mapped to the remaining REs, excluding the REs to which CORESET, DMRS, and SSB are mapped. In the frequency domain, CSI-RS may be configured for the entire bandwidth, a portion of the bandwidth (BWP), or a portion of the bandwidth. CSI-RS may be transmitted at each RB within the configured bandwidth (i.e., density=1), or at every second RB (e.g., even or odd RB) (i.e., density=1 / 2). When CSI-RS is used as a Tracking Reference Signal (TRS), a single-port CSI-RS may be mapped to three subcarriers in each resource block (i.e., density=3). In the time domain, one or more CSI-RS resource sets may be configured for the terminal. Each CSI-RS resource set may include one or more CSI-RS configurations. Each CSI-RS resource set may be configured periodicly, semipersistently, or non-periodically.

[0263] - CSI report configuration may include settings for feedback type, measurement resources, report type, etc. NZP-CSI-RS resource sets may be used for the CSI report configuration of the terminal. NZP-CSI-RS resource sets may be associated with CSI-RS or SSB. Additionally, multiple periodic NZP-CSI-RS resource sets may be configured as TRS resource sets. (i) Feedback types may include Channel Quality Indicator (CQI), Precoding Matrix Indicator (PMI), CRI (CSI-RS Resource Indicator), SSBRI (SSB Resource block Indicator), LI (Layer Indicator), Rank Indicator (RI), Layer 1-Reference Signal Received Strength (RSRP), etc. (ii) Measurement resources may include settings for downlink signals and / or downlink resources for which the terminal performs measurements to determine feedback information. Measurement resources may be set as ZP and / or NZP CSI-RS resource sets associated with CSI reporting settings. NZP CSI-RS resource sets may include CSI-RS sets or SSB sets. For example, L1-RSRP may be measured against CSI-RS sets or against SSB sets. (iii) Report type may include settings for the timing and uplink channel, etc. for which the terminal performs reporting. Report timing may be set to periodic, semi-persistent, or non-periodic. Periodic CSI reporting may be transmitted over PUCCH. Semi-persistent CSI reporting may be transmitted over PUCCH or PUSCH based on MAC CE indicating activation / deactivation. Non-periodic CSI reporting may be indicated by DCI signaling.For example, the CSI request field of an uplink grant can specify one of various report trigger sizes. Non-periodic CSI reports can be transmitted over PUSCH.

[0264] The terminal can measure CSI based on configuration information related to CSI. CSI measurement may include a procedure for receiving CSI-RS and acquiring CSI by computing the received CSI-RS.

[0265] The terminal can transmit CSI reports to the base station. For CSI reporting, the time and frequency resources available to the UE are controlled by the base station. Channel state information (CSI) may include at least one of a channel quality indicator (CQI), a precoding matrix indicator (PMI), a CSI-RS resource indicator (CRI), an SS / PBCH block resource indicator (SSBRI), a layer indicator (LI), a rank indicator (RI), L1-RSRP, and / or L-SINR.

[0266] The time domain behavior of CSI reporting supports periodic, semi-persistent, and aperiodic. i) Periodic CSI reporting is performed on short PUCCH or long PUCCH. The periodicity and slot offset of periodic CSI reporting can be set to RRC; refer to CSI-ReportConfig IE. ii) Semi-periodic (SP) CSI reporting is performed on short PUCCH, long PUCCH, or PUSCH. In the case of SP CSI on short / long PUCCH, the periodicity and slot offset are set to RRC, and CSI reporting is activated / deactivated by separate MAC CE / DCI. In the case of SP CSI on PUSCH, the periodicity of SP CSI reporting is set to RRC, but the slot offset is not set to RRC, and SP CSI reporting is activated / deactivated by DCI (format 0_1). For SP CSI reporting over PUSCH, a separate RNTI (SP-CSI C-RNTI) is used. The timing of the initial CSI report follows the PUSCH time domain allocation value specified in the DCI, while subsequent CSI reporting timing follows the period set by the RRC. DCI format 0_1 ​​includes a CSI request field and can activate / deactivate specific configured SP-CSI trigger states. SP CSI reporting has the same or similar activation / deactivation mechanisms as those used for data transmission over SPS PUSCH.iii) aperiodic CSI reporting is performed on PUSCH and triggered by DCI. In this case, information related to the trigger of aperiodic CSI reporting can be transmitted / instructed / set via MAC-CE. For an AP CSI with AP CSI-RS, the AP CSI-RS timing is set by RRC, and the timing for AP CSI reporting is dynamically controlled by DCI.

[0267] NR Precoder

[0268] Precoders defined in NR standards (e.g., codebooks for CSI reporting or PMI codebooks) can be classified into Type I codebooks, Type II codebooks, and Enhanced Type II codebooks.

[0269] - Type I Codebook

[0270] Type I codebooks are primarily targeted at Single User (SU)-MIMO, which supports both high and low orders. Type I codebooks can be divided into (i) single-panel codebooks and (ii) multi-panel codebooks. (i) Single-panel codebooks may be based on the assumption that a terminal receives downlink transmissions from a single antenna panel. (ii) Multi-panel codebooks may support base station configurations using multiple (e.g., 2 or 4) antenna panels. Unlike single-panel codebooks, which support ranks 1 through 8, multi-panel codebooks may support ranks 1 through 4.

[0271] The Type I codebook can be composed of the selection of preferred DFT vector(s) from the oversampled DFT vector set, which is the SD (spatial domain) basis, and the indication aspect for the co-phase of the base station antenna's cross-polarization.

[0272] - Type II Codebook

[0273] Type II codebooks can primarily support MI-MIMO supporting up to two layers. Compared to Type I, Type II codebooks can provide more accurate PMI, but signaling overhead may increase accordingly. In Type II codebooks, PMI can identify sets of beams and sets of amplitude coefficients. Amplitude coefficients can be used to generate a weighted sum of beams. Type II codebooks can also identify phase shifts for co-phasing between beams. Type II port selection codebooks can be configured based on broadband / long-term PMI components (e.g., i1) and subband / short-term PMI components (e.g., i2).

[0274] In the case of Type II codebooks, multiple SD basis DFT vectors are selected, and the selected DFT vectors are linearly combined to achieve high resolution and excellent MU-MIMO performance.

[0275] - Enhanced Type II Codebook

[0276] Enhanced Type II codebooks (e.g., Rel. 16 DL codebook) are designed to address the disadvantage of CSI overhead associated with existing Type II codebooks. Enhanced Type II was introduced by reducing the payload of the codebook by taking into account the correlation of the frequency axis.

[0277] In Enhanced Type II codebooks (e.g., Rel-16 DL codebook), the precoding matrix W is W = W1*W2*W3 (or W1*W c *W H FIt can be expressed as follows. W1 corresponds to the SD basis related to SD compression, W3 corresponds to the FD basis related to FD compression, and W2 corresponds to the linear combining (LC) coefficients according to the FD compression of W3. If the terminal determines matrix W as an enhanced Type II PMI, it may report the indices of W1, the coefficients of W2, and the indices of W3 to the network. The dimension of matrix W is P(=2N1*N2)*N3, W1 may be P*2L, W2 may be 2L*M, and W3 may be N3*M. N1 may represent the number of columns in the first domain (the number of antenna ports in the first domain within the panel), and N2 may represent the number of rows in the second domain (the number of antenna ports in the second domain within the panel). The terminal can select 2L basis beam vectors in relation to W1, select M LC coefficients in relation to W2, and select M FD basis vectors in relation to W3 (where each vector is an N3*1 orthogonal DFT vector). L is a parameter for SD compression, representing the number of SD beams, and can be 2, 3, or 6. N3 and M are parameters for FD compression, where N3 is the DFT size for FD compression, and N3=N SB It is expressed as *R, where R is the granularity between CQI and PMI and can be 1 or 2.

[0278] - NR's DL Precorder Cycling

[0279] Referring to Section 5.2.1.4.2 of the NR standard document, CSI reporting is configured according to the reportQuantity setting. For example, if reportQuantity is set to cri-RI-i1-CQI, the UE can report wideband PMI indicator i1 based on the Type-I single panel codebook and calculate and report CQI based on this.

[0280] NR supports precoding PDSCH transmission resources in units of Precoding Resource Groups (PRGs) by considering frequency-selective channels. The size of a PRG is set by the upper-layer parameter pdsch-BundleSizeForCSI. Since the subband PMI i2 is not reported when cri-RI-i1-CQI is configured, the UE can calculate the CQI by assuming an arbitrary precoder for each PRG within the set of precoder candidates. For example, the UE can calculate the CQI under the assumption of precoder cycling at the PRG level.

[0281] Meanwhile, when reportQuantity is cri-RI-PMI-CQI or cri-RI-LI-PMI-CQI, since the UE reports a specific PMI, the CQI is calculated based on a single precoder corresponding to that PMI, and it can be understood that the precoder cycling assumption per PRG is not used.

[0282] UL precoder cycling, Cycling unit determination & Codebook indication

[0283] In the following description, 'beam' may refer to a (source / reference) RS for a 'spatial Tx / Rx filter' or 'spatial relation', and can be interpreted as a QCL (source / reference) RS, a (DL / UL / joint) TCI state, or (in the case of an uplink) a spatial relation RS (corresponding ID).

[0284] In NR, codebook-based UL and non-codebook-based UL are supported as transmission techniques for UL. Since these transmission methods operate based on SRI / precoder instructions derived from the base station's SRS measurement, performance may degrade in environments where the terminal moves quickly and / or channel variation is severe.

[0285] In this disclosure, methods are proposed to overcome / supplement the disadvantages / limitations of the measurement / report signaling framework of existing NR systems. For example, (semi)-OL techniques such as precoder cycling, which is an open-loop method, are proposed.

[0286] Various transmission techniques such as spatial multiplexing and (semi)-OL (open loop) can be considered for transmitting UL signals (e.g., PUSCH) in Rel-20 NR MIMO or subsequent releases or 6G.

[0287] As previously explained, referring to the existing NR document TS 38.214 section 5.2.1.4.2, in DL, for example, when the report quantity is set to 'cri-RI-i1-CQI', it is assumed that precoder cycling is set, and the terminal operation for this is defined. On the other hand, NR's UL does not support such transmission schemes and only supports transmission techniques such as wideband precoding for the entire configured UL band, so there are limitations regarding the improvement of UL reliability.

[0288] To overcome such limitations, according to one embodiment of the present disclosure, the above-described (semi)-OL technique may be applied to UL. In particular, UL precoder cycling may be considered to obtain diversity gain by varying the precoder within the transmission UL band for (semi)-OL transmission. A method to effectively support such UL precoder cycling is proposed.

[0289] Proposal 1

[0290] For uplink precoder cycling, a precoder cycling unit in the form of a frequency unit and / or a time unit may be introduced. The terminal may receive instructions / sets from the base station for one or more precoder sets to be cycled for each precoder cycling unit, perform UL precoder cycling, and transmit a UL signal, for example, PUSCH, to the base station.

[0291] For example, an embodiment for setting a Frequency domain cycling unit / time domain cycling unit may include at least one of the following.

[0292] (1) Frequency domain cycling unit

[0293] 1) Method 1: N RBs (resource blocks) can be configured / defined as a single cycling unit. For example, N can be configurable or fixed according to the configured BW, and a formula or table may be defined / provided for the fix.

[0294] 2) Method 2: UL SB (subband) can be defined / configured and UL PRG can be defined / configured in units of M SBs. PRG units can be considered as cycling units.

[0295] 3) Method 3: Values ​​based on terminal capability reports can be set / applied as the maximum / minimum cycling unit.

[0296] 4) Method 4: When a base station sets / signs information about a frequency domain cycling unit (e.g., number of PRGs X) to a terminal according to the configured BW, the terminal can determine the size of the frequency domain cycling unit based on the number of PRGs X and apply cycling. For example, the size of the frequency domain cycling unit can be determined as Ceiling [configured BW size / X].

[0297] 5) Method 5: For frequency domain cycling units, the PRG of the DL defined as a precoding resource group can be reused as is.

[0298] (2) Time domain cycling unit

[0299] 1) Method 1: A single or multiple time units (e.g., symbol, slot, msec) can be set as a single time domain cycling unit.

[0300] 2) Method 2: Values ​​based on terminal capability reports can be set / applied as maximum / minimum cycling units.

[0301] 3) Method 3: If UL time domain DMRS bunding is supported, the time domain cycling unit can be set as a bundling unit.

[0302] 4) In addition to (or separately from) method 1 and / or 2, a window for performing cycling may be separately set.

[0303] Meanwhile, the time domain unit for precoder cycling can be applied / configured / instructed in two steps. For example, the unit associated with the first step is set to a larger time unit (e.g., 10 msec), and this unit may consist of multiple sub-units (second step units), which share the same precoder set. The second step unit is configured by dividing the first step unit into smaller time units (e.g., slots), and based on Proposal 1, it can be used as a unit for cycling a given precoder set. The precoder set configured in the first time domain unit may be set by the base station in advance or by a specific rule. If configured by a rule, it can be agreed that the TPMI group index / ID, etc., are set according to that specific rule. For example, it can be agreed that TPMI group indices 1, 2, 3, and 4 cycle in a round-robin fashion. When configured by a base station, the initially configured TPMI group index is used, which can be updated later via MAC-CE / DCI, and the unit in which the TPMI set is applied may be the 1st time unit. If there is no signaling related to such an update, the terminal can perform precoder cycling using the most recent / latest TPMI set.

[0304] Below, more specific examples regarding the settings / definitions of the above Frequency domain cycling unit / Time domain cycling unit are described.

[0305] For example, for base station precoder cycling, the base station may set / instruct a terminal to a TPMI group / set, and the terminal may transmit a UL signal, e.g., PUSCH, by applying a precoder within the set TPMI group / set to a frequency cycling unit / time cycling unit according to a predetermined pattern / sequence. The predetermined pattern / sequence may be set based on higher layer parameters such as RRC, or determined as a function of system parameters (e.g., modulo operation with SFN (or subframe number) or CCE index) to reduce signaling overhead. As a specific example of the case where it is determined by system parameters, when SFN=8, modulo 5 (the above value may be additionally provided) is performed on SFN=8 to determine the starting index / sequence of the precoder as 3, and cycling may be applied by sequentially increasing the precoder index / sequence starting from the starting index 3.

[0306] FIG. 13 is a diagram illustrating UL precoder cycling in the time and frequency domain according to one embodiment. FIG. 13 illustrates a case where time domain and frequency domain precoder cycling are set simultaneously. However, the application of the present disclosure does not necessarily presuppose that time domain and frequency domain precoder cycling are performed together, and may be applied to cases where only time domain precoder cycling is performed or only frequency domain precoder cycling is performed.

[0307] In Fig. 13, it is assumed that TPMI 1, 2, 3, and 4 are set by the base station as TPMI groups / sets for UL precoder cycling. Additionally, it is assumed that the frequency cycling units are 0, 1, and 2, and the window for the time domain unit is 6.

[0308] In the frequency-first mapping of Fig. 13 (a), precoders can be mapped in a pre-defined order, with the frequency domain unit being the first. Specifically, in example (a), the TPMI sequence 1→2→3→4→1 is assumed, and this sequence can be set by the base station on the terminal or agreed upon in advance between the base station and the terminal. After the frequency domain unit is mapped first, precoders can be mapped by increasing the time domain unit. It is assumed that once all TPMIs within a TPMI group / set are mapped, the process returns to the first TPMI using a wrap-around method (or modulo operation, etc.).

[0309] The time-first mapping in (b) of Fig. 13 is a method in which precorder mapping is performed first on a given time window, and then precorder mapping is performed while increasing the frequency domain.

[0310] Circular mapping (c) in Fig. 13 is a combination of frequency-first mapping (a) and time-first mapping, meaning a method in which mapping occurs at a distance of at least a specific index value (e.g., 1 in the example of Fig. 13) in both the frequency domain and the time domain. Specifically, in the frequency domain, precorders are mapped at a constant index interval between each unit, and in the time domain, precorders are mapped at a constant index interval between each unit. At this time, the index difference between the time domain and the frequency domain may be determined differently. For example, in the example of (c), when the time domain index difference is 2, mapping occurs from time domain unit 1 along the frequency domain in the order TPMI 3→4→1.

[0311] As another example, cycling on / off can be set for each domain. For instance, in the case of time domain repetition, 'frequency domain cycling on' and 'time domain cycling off' can be used to maintain the same patterns of the precoders applied to the frequency domain unit across each repetition.

[0312] Alternatively, a pattern for maintaining or not maintaining time domain cycling may be set or defined. For example, a pattern such as 1010, 1100, or 1111 (e.g., bitmap pattern) can be set, and time units set to 1 may have the same frequency domain precoder cycling pattern, while time units set to 0 may have the same frequency domain precoder cycling pattern. For convenience, the cycling window in the time domain was assumed to be 4, but due to the length of the bitmap pattern (e.g., the number of (effective) bits included in the bitmap), a separate window setting may not be necessary. In this way, cycling gain and coverage gain due to repetition can also be satisfied.

[0313] Meanwhile, UL DMRS time domain bundling can be considered as in (2) time domain unit 3) method 3. Such time domain bundling can mean improving channel estimation performance by joint channel estimating DMRS across multiple slots. When UL DMRS time domain bundling is supported, it can be assumed that the same precoder is applied to the bundled slots. Alternatively, when setting / instructing a time domain cycling pattern based on a bitmap as in the bitmap pattern example above, the terminal may not expect different precoders to be set / instructed within the time domain bundling unit. Alternatively, even if different precoders are set / instructed within the time domain bundling unit, the terminal may ignore such setting / instruction and perform UL transmission by applying the same precoder to the bundling unit.

[0314] Proposal 2

[0315] For uplink precoder cycling, consider at least one of the following codebook settings.

[0316] (1) Method 1: UL precoder based

[0317] (2) Method 2: DL precoder based

[0318] (3) Method 3: Codebook definition for Precoder Cycling

[0319] (4) Method 4: The terminal reports codebook information to be used for precoder cycling to the base station

[0320] In the case of Method 1 in Proposal 2 above, an uplink codebook defined in LTE / NR, etc., can be used. Alternatively, an uplink codebook to be used in future releases / generations (e.g., 6G) can be used. Generally, an uplink codebook is a codebook applied to 2 / 3 / 4 / 8 UL PUSCH ports and has the attribute of being applied on a wideband basis. Furthermore, unlike DL codebooks, UL codebooks are indicated for a single codebook (across rank, i.e., joint TRI, TPMI instruction) through DCI. To apply UL precoder cycling based on such UL codebooks, the following methods can be applied.

[0321] - Method 1-1: An existing UL codebook can be grouped according to a specific rule to be defined as a DL dual codebook, and the corresponding group index can be instructed to the terminal. The terminal can perform precoder cycling using the TPMIs included in the instructed group index.

[0322] For example, if there are 1 to 20 indices in a 4-port rank 1 codebook, 4 TPMIs can be defined as one group, and 5 groups can be defined. For instance, TPMIs 1-4 can be defined as group #1, TPMIs 5-8 as group #2, and so on. The above grouping can be defined in a rank-specific manner to perform more flexible grouping.

[0323] - Method 1-2: The base station can instruct the terminal to use TPMIs for precoder cycling from a given codebook using a bit-map (per rank), etc. For example, if there are 1 to 20 indices in a 4-port rank 1 codebook, a 20-bit bitmap can be used to instruct the precoders to be used for precoder cycling. For example, a precoder corresponding to a bit value "1" is used for precoder cycling, and a precoder corresponding to a bit value "0" may be a precoder not used for precoder cycling.

[0324] On the other hand, as the size of the codebook increases, there is a disadvantage in that the payload of the aforementioned bitmap increases. As a solution to this, the payload can be saved by utilizing a combinatorial number (N choose K where N is # of codebook size and K is # of precoder for cycling) to specify the (multiple) precoders participating in cycling.

[0325] In the case of Method 2 in Proposal 2, it means utilizing a DL codebook for UL precoder cycling. To instruct the terminal on information regarding the set for precoder cycling, the base station may instruct the terminal via DCI the codebook parameter i1 (i.e., the spatial domain basis group indicator i11 and i12 corresponding to W1 in the dual codebook structure). The terminal may use the codebook corresponding to the above i1 for UL precoder cycling. As a simple example, the base station may receive the SRS transmitted by the terminal for UL transmission, search for the most suitable codebook index in the DL codebook, and instruct the terminal on precoder(s) information (e.g., i1 index). Alternatively, to instruct the base station's appropriate i1 index, the base station may utilize some or all of the following information.

[0326] - The terminal transmits a precoded SRS based on a precoder included in a specific DL codebook i1 index to the base station, and the base station receives the precoded SRS and can determine / identify the i1 index. To determine the i1 index to be used for the terminal's SRS transmission, the base station may pre-set a codebook or codebook subset for the terminal to precode the SRS. The terminal may precode the SRS based on a precoder within the codebook or codebook subset according to the base station's settings or a pre-defined rule and transmit it to the base station.

[0327] - The terminal may report to the base station information such as receiving beam information (e.g., index, receiving RSRP, terminal's rotation information) and / or corresponding CSI-RS resource indicators that receive a specific CSI-RS. Here, the specific CSI-RS may be a resource set for the purpose of determining the UL transmission precoder, and this resource may be a resource in which the base station's receiving beam precoded to receive the terminal's UL signal is precoded. Additionally, since the coordinate of the receiving beam may change due to the movement of the terminal, the terminal's rotation information (from a specific reference point) may be additionally reported to the base station.

[0328] In the case of Method 2 of Proposed 2, since a DL codebook is used, the DL codebook size may be larger than the UL codebook, and consequently, the DCI overhead required for precoder cycling instructions may be large. To reduce this, a separate codebook subset restriction (CBSR) may be set, and based on the reduced codebook size, precoder cycling information such as i1 may be instructed to the terminal. For example, a separate CBSR may be instructed / set to the terminal for the effective instruction of the UL codebook, rather than for the primary purpose of the CBSR (codebook subset restriction), which is DL interference. Meanwhile, in the case of existing NR standards, the CBSR was used / set to exclude the use of precoders that cause interference to neighboring terminals / cells. On the other hand, in the present disclosure, the CBSR has a completely different purpose and effect from the CBSR of existing NR in terms of setting candidates to be used for UL precoder cycling.

[0329] In the case of the above-mentioned Proposal 2 method 3, a new codebook for precoder cycling is defined separately from the existing UL precoder design, and when the precoder cycling mode is explicitly or implicitly set by the base station, it is agreed that the codebook is used for operation, or a separate codebook type may be set by the base station. The codebook dedicated to precoder cycling may also be defined as a subset of a specific codebook (e.g., NR UL / DL codebook).

[0330] In the case of the above-mentioned Proposal 2 Method 4, the terminal reports codebook information to be used for precoder cycling to the base station. As an example of Method 4, the terminal can report codebook information to be used for UL precoder transmission to the base station by utilizing the DL channel reciprocity of Method 2. Since the above codebook information is not a necessary element for the base station to decode the terminal's received signal, in addition to the above-mentioned explicit codebook information, only information such as whether there is a change in the codebook / codebook subset for precoder cycling (e.g., a 1-bit indicator) may be reported to the base station. For example, the base station may only set the mode for UL precoder cycling to the terminal, and the precoder selection and / or application of precoder cycling may be performed by the terminal implementation. However, regarding the performance management of precoder cycling in the above mode, the base station may separately instruct / set the terminal to change instructions / requests regarding the precoder set used for precoder cycling applied by the terminal itself.

[0331] For UL transmission in NR, separate codebook subsets are supported based on the terminal's coherency capability. Here, coherency refers to whether the terminal can maintain relative phase between SRS and PUSCH ports from the time of SRS transmission to PUSCH transmission. Based on this capability, codebook subsets corresponding to non-coherent, partial coherent, and full-coherent capabilities have been defined. Non-coherent refers to cases where it is difficult to maintain relative phase on any port; partial coherent refers to cases where relative phase is maintained at the level of partial ports or port groups; and full-coherent refers to cases where relative phase is maintained on all ports. Characteristically, regarding codebook subsets, a terminal with a higher level of coherency can support a codebook corresponding to a lower level of coherency, whereas a terminal with a lower level of coherency cannot support a codebook corresponding to a higher level. In other words, full coherent UEs can support non / partial / full coherent codebooks, while non-coherent UEs are designed to support only non-coherent codebooks. When using a codebook that takes into account the coherency of such a terminal (e.g., NR UL codebook), UL precoder cycling must be performed using a codebook that matches this coherency to maximize performance gains.

[0332] Figure 14 illustrates an example of a 4-port non / partial / full coherent codebook subset (precoder) extracted from the NR standard document TS38.211.

[0333] In Fig. 14, precoders that are not labeled as either non-coherent or partial-coherent may be precoders that are only usable in full coherent.

[0334] For non-coherent terminals, precoder cycling is performed using TPMI(s) selected only from the non-coherent codebook. For partial coherent terminals, precoder cycling can be performed using TPMI(s) selected only from the partial coherent codebook, or using TPMI(s) selected only from the partial coherent codebook + non-coherent codebook. For full coherent terminals, precoder cycling can be performed using TPMI(s) selected only from the full coherent codebook, or using TPMI(s) selected only from the partial coherent codebook + non-coherent codebook.

[0335] Referring to Fig. 15, for some partial coherent codebooks indicated by thick solid lines, the TPMI indices for a specific port group are composed of the same precoding vector. For rank 2, 4-port TPMI indices 6 and 7 (coherent antenna port groups 1 and 3, 2 and 4), it can be seen that the codebook coefficients corresponding to ports 1 and 3 are identical. Therefore, if such identical TPMIs are included in the TPMI group / set to be used for precoder cycling, the diversity gain may decrease. Thus, when setting / determining / instructing the TPMI group for precoder cycling, the application of the same precoder (across layers) from the perspective of coherent port groups during frequency domain (FD) and / or time domain (TD) precoder cycling can be restricted. For example, in the example of Fig. 15, TPMI 6 and 7 may not be set to the same group / set simultaneously in the precoder cycling TPMI set, 8 and 9 may not be set to the same group / set simultaneously, and 10 and 11 may not be set to the same group / set simultaneously.

[0336] However, as mentioned above, for non-coherent codebooks, it may be difficult to obtain port domain precoding gain (array gain) even with precoder cycling, but port-selection gain can be obtained. However, in such cases, since PUSCH transmissions are distributed evenly to the configured ports, non-coherent codebooks with many ports corresponding to 0 may suffer a loss in terms of transmission power, potentially causing coverage loss. Therefore, for non-coherent / partially-coherent terminals, if precoder cycling is configured / instructed, it may be considered that WB transmission is performed based on a single full coherent precoder. Alternatively, if precoder cycling is configured / instructed, the available codebooks may be limited to full coherent codebooks. For example, in the case of a full coherent terminal, the codebook configured for precoder cycling may be limited to a full coherent codebook.

[0337] Meanwhile, if specific codeword (CW) decoding fails during PUSCH transmission, the base station can schedule a retransmission to the terminal. In this case, rather than applying precoder cycling during the retransmission, it may be better in terms of reliability to use the specific precoder with the highest transmission efficiency to perform WB / SB precoding and transmit. Therefore, it can be agreed upon or predefined that the base station turns off precoder cycling during retransmission, and if there is a signaling that allows dynamically turning the transmission mode on / off, this can be used to turn off precoder cycling during retransmission. When precoder cycling is turned off in this way (or fallback mode), the existing scheduling method can be used. Alternatively, to reduce the payload within the DCI, the TPMI / TRI field within the retransmission-scheduled DCI can indicate / set the precoder to be used for retransmission from among the precoders within the precoder cycling TPMI group / set preconfigured in advance (e.g., scheduled during RRC or initial transmission), thereby reducing signaling overhead.

[0338] Proposal 3

[0339] Meanwhile, to reduce signaling overhead, the precoder cycling technique described above can also be applied to the configured grant PUSCH (CG-PUSCH) method, which performs PUSCH transmission based on information pre-configured by RRC, etc.

[0340] For CG-PUSCH-based uplink precoder cycling, an initial precoder cycling TPMI set is defined using RRC signaling, and the initial precoder cycling TPMI set can be updated later based on MAC-CE or DCI.

[0341] In the case of Proposal 3, for CG-PUSCH, there is an advantage in that dynamic signaling (e.g., DCI) can be reduced by pre-configuring the precoder / rank to be used for PUSCH transmission via RRC. However, since this configuration does not take into account the terminal's current channel state, performance degradation may occur. To address this, we propose a method in which the base station updates the initial precoder cycling set configured for precoder cycling. Based on this, the current channel conditions can be better considered during CG-PUSCH transmission, thereby improving uplink transmission yield and BLER (block error ratio) performance. The method for updating the initial precoder cycling set may be based, for example, on MAC-CE and / or DCI signaling. In addition, for the precoder cycling described in Proposal 1, the FD / TD precoder cycling unit (e.g., PRG size in the case of an FD unit) can be set, and if the initial unit is set to RRC, this information can also be updated through DCI / MAC-CE. The timing for using the updated value can be agreed upon / predefined as applying it after X (X=0,1,2,..) time (slot / symbol, msec) from the time n when the update signaling is received, or after Y (Y=0,1,2,..) time (slot / symbol, msec) from the time when the ACK for the reception of the information is transmitted to the base station.

[0342] In the case of Proposals 1 / 2 / 3, precoder cycling was explained using an example of operation primarily based on a codebook-based uplink, but it can also be extended and applied to non-codebook-based uplink operations. In non-codebook-based uplink transmission, a terminal transmits multiple SRS resources (multiple 1-port SRS resources) that it has precoded in implementation to a base station, and the base station transmits a combination of SRS resources to be used for PUSCH transmission to the terminal via the SRI field based on the reception of the SRS resources, and the terminal performs PUSCH transmission with precoding based on the combination of SRS resources. When extending UL precoder cycling to the NCB-based UL, for example, '1st step: the process of selecting a combination of resources to perform cycling on multiple SRS resources that the terminal has precoded in implementation' can be replaced with a process for selecting a precoder cycling precoder set, and '2nd step: the process of instructing the combination of SRS resources' can be replaced with a process for instructing the precoder cycling precoder set. The subsequent process may follow some or all of Proposals 1 / 2 / 3. The current SRI (SRS resource indicator) is indicated in the form of a combination that does not distinguish the order of SRS resources. However, in the case of UL precoder cycling, the order in which a resource is applied to which FD / TD basis is also important; therefore, the SRS resources to be used in UL precoder cycling may be indicated in the form of a permutation, so that the base station can determine / control which order of SRS resources corresponds to which FD / TD basis.In addition, for this combination, when setting the number of SRS, in NCB (non-codebook based) UL, only the maximum rank / layer / port number is set. However, to appropriately select a precoder cycling group / set for UL precoder cycling, the terminal may set a parameter separate from the above-mentioned higher layer parameter. For example, a value larger than the parameter for the maximum rank / layer / port may be set, and a parameter for the size of the precoder cycling group / set may also be set separately, allowing for effective instruction of the base station's precoder cycling group / set. If the number of SRS resources used in NCB UL cannot be increased as described above (e.g., due to UE capability), instructions for precoding changes (e.g., update / switching) of precoded SRS resources may be instructed / set to the terminal via MAC-CE / DCI to improve the performance of UL precoder cycling.

[0343] The above proposals 1 / 2 / 3 may be used alone or composed of combinations.

[0344] Through the above embodiments, we have examined ways to effectively support UL precoder cycling. The proposed method can improve UL reliability, such as achieving excellent BLER (block error rate) performance through the acquisition of UL diversity. In addition, UL precoder cycling, which operates as a type of SB precoding, has the advantage of significantly reducing overhead for instructions such as SB TPMI.

[0345] FIG. 16 is a diagram illustrating the operation of a terminal and a base station according to one embodiment.

[0346] Referring to FIG. 16, the terminal can transmit a terminal capability report to the base station (A05). The terminal capability report may include terminal capability information related to precoder cycling (e.g., supported FD / TD unit size), and / or information regarding coherent transmission capability.

[0347] The terminal can receive various configuration information from the base station through at least one RRC signaling (A10). The configuration information may include, for example, UL RS (e.g., SRS) configuration information. The configuration information may also include configuration information for PUSCH and / or UL precoder cycling.

[0348] The terminal can transmit SRS to the base station (A15).

[0349] The base station can determine the precoder cycling TPMI set and / or TD / FD cycling unit based on the UL RS received from the terminal.

[0350] The terminal may receive UL grant (UL scheduling DCI) and / or UL precoder cycling information from the base station (A20). At this time, the UL precoder cycling information may include instructions for a cycling TPMI set.

[0351] The terminal may transmit a UL signal to the base station based on UL precode cycling (A20). The UL signal may include PUSCH and / or UL DMRS.

[0352] In FIG. 16, the operation of the terminal / base station may be performed by the device (200) of FIG. 3. For example, one or more processors (202) of the device (200) of FIG. 3 may be configured to perform the terminal / base station operation according to FIG. 16. Furthermore, one or more memories (204) of the device (200) may store instructions for performing the method in the example of FIG. 16 or in various examples of the foregoing specification when executed by one or more processors (202).

[0353] Depending on the implementation of the embodiment, some terminal / base station operations in FIG. 16 may be omitted.

[0354] FIG. 17 illustrates the flow of a method performed by a terminal according to one embodiment. FIG. 17 is an example of implementation for at least some of the embodiments described above, and the previously described content may be referenced unless otherwise noted.

[0355] Referring to 17, the terminal can receive configuration information related to uplink precoding (B05).

[0356] The terminal can transmit a precoded uplink signal based on the above setting information (B10).

[0357] The resources for the uplink signal may include one or more frequency resource units and one or more time resource units.

[0358] The above uplink signal can be precoded based on precoder cycling for at least one of each frequency resource unit and / or each time resource unit.

[0359] The above setting information may include information about the precorders for the precorder cycle.

[0360] The above precoders may be a subset of an uplink codebook, a subset of a downlink codebook, or a subset of a precoder cycle-only codebook.

[0361] The above terminal can precode the uplink signal by circulating precoders in a specific order for each combination of frequency resource unit and each time resource unit.

[0362] The specific order mentioned above may be a frequency first mapping order, a time first mapping order, or a time-frequency circular mapping order.

[0363] The above precorder cycle can be performed based on at least one of the index of the precorder, the index of each frequency resource unit, and / or the index of each time resource unit.

[0364] The above terminal can receive DCI (downlink control information) that schedules the uplink signal.

[0365] The above DCI may include at least one of information about the precorders for the precorder cycle or information about the cycle order of the precorders.

[0366] The above uplink signal may be a PUSCH (physical uplink shared channel).

[0367] The above PUSCH is a CG (configured grant)-PUSCH, and the above configuration information may include CG configuration information.

[0368] The above precoder cycle may be a codebook-based precoder cycle or a non-codebook-based precoder cycle using an SRS (sounding reference signal).

[0369] FIG. 18 illustrates the flow of a method performed by a base station according to one embodiment. FIG. 18 is an example of implementation for at least some of the embodiments described above, and the previously described content may be referenced unless otherwise noted.

[0370] Referring to FIG. 18, the base station can transmit configuration information related to uplink precoding (C05).

[0371] The base station can receive a precoded uplink signal based on the above configuration information (C10).

[0372] The resources for the uplink signal may include one or more frequency resource units and one or more time resource units.

[0373] The above uplink signal can be precoded based on precoder cycling for at least one of each frequency resource unit and / or each time resource unit.

[0374] The above setting information may include information about the precorders for the precorder cycle.

[0375] The above precoders may be a subset of an uplink codebook, a subset of a downlink codebook, or a subset of a precoder cycle-only codebook.

[0376] For each combination of frequency resource unit and each time resource unit, the precoders are circulated in a specific order, and the uplink signal can be precoded.

[0377] The specific order mentioned above may be a frequency first mapping order, a time first mapping order, or a time-frequency circular mapping order.

[0378] The above precorder cycle can be performed based on at least one of the index of the precorder, the index of each frequency resource unit, and / or the index of each time resource unit.

[0379] The above base station can transmit downlink control information (DCI) for scheduling the uplink signal.

[0380] The above DCI may include at least one of information about the precorders for the precorder cycle or information about the cycle order of the precorders.

[0381] The above uplink signal may be a PUSCH (physical uplink shared channel).

[0382] The above PUSCH is a CG (configured grant)-PUSCH, and the above configuration information may include CG configuration information.

[0383] The above precoder cycle may be a codebook-based precoder cycle or a non-codebook-based precoder cycle using an SRS (sounding reference signal).

[0384] The embodiments described above are combinations of the components and features of the present disclosure in a specific form. Each component or feature should be considered optional unless otherwise explicitly stated. Each component or feature may be implemented in a form not combined with other components or features. Additionally, it is possible to construct embodiments of the present disclosure by combining some components and / or features. The order of operations described in the embodiments of the present disclosure may be changed. Some components or features of one embodiment may be included in another embodiment, or may be replaced with corresponding components or features of another embodiment. It is obvious that embodiments may be constructed by combining claims that are not explicitly related in the claims, or that they may be included as new claims by amendment after filing.

[0385] It is obvious to those skilled in the art that the present disclosure may be embodied in other specific forms without departing from the features of the present disclosure. Accordingly, the foregoing detailed description should not be interpreted restrictively in all respects and should be considered illustrative. The scope of the present disclosure shall be determined by a reasonable interpretation of the appended claims, and all modifications within the equivalent scope of the present disclosure are included within the scope of the present disclosure.

[0386] The present disclosure may be used in a terminal, base station, or other equipment of a wireless mobile communication system.

Claims

1. In a method performed by a terminal, Receive configuration information related to uplink precoding; and It includes transmitting a precoded uplink signal based on the above setting information, and The resources for the uplink signal include one or more frequency resource units and one or more time resource units, and A method in which the uplink signal is precoded based on precoder cycling for at least one of each frequency resource unit and / or each time resource unit.

2. In Paragraph 1, A method in which the above setting information includes information about the precorders for the precorder cycle.

3. In Paragraph 2, The above precoders are a subset of an uplink codebook, a subset of a downlink codebook, or a subset of a precoder cycle-only codebook.

4. In Paragraph 1, A method in which the above terminal precodes the uplink signal by circulating precoders in a specific order for each combination of frequency resource unit and each time resource unit.

5. In Paragraph 4, A method in which the above specific order is a frequency first mapping order, a time first mapping order, or a time-frequency circular mapping order.

6. In Paragraph 1, A method in which the above-mentioned precorder cycle is performed based on at least one of the index of the precorder, the index of each frequency resource unit and / or the index of each time resource unit.

7. In Paragraph 1, It further includes receiving DCI (downlink control information) that schedules the uplink signal, and A method in which the above DCI includes at least one of information about the precorders for the precorder cycle or information about the cycle order of the precorders.

8. In Paragraph 1, The above uplink signal is a PUSCH (physical uplink shared channel), a method.

9. In Paragraph 8, The above PUSCH is CG (configured grant)-PUSCH, and A method comprising the above setting information including CG setting information.

10. In Paragraph 1, A method in which the above precoder cycle is a codebook-based precoder cycle or a non-codebook-based precoder cycle using an SRS (sounding reference signal).

11. A computer-readable non-transitory recording medium storing a program for performing the method described in claim 1.

12. Regarding the device, At least one processor; and It includes at least one memory configured to store instructions that cause the at least one processor to perform operations by being executed by the at least one processor, and The operations of the above processor are, Receive configuration information related to uplink precoding; and It includes transmitting a precoded uplink signal based on the above setting information, and The resources for the uplink signal include one or more frequency resource units and one or more time resource units, and A device in which the above uplink signal is precoded based on precoder cycling for at least one of each frequency resource unit and / or each time resource unit.

13. In Paragraph 12, The above device is a device comprising a terminal including a transceiver or a processing device configured to control the terminal.

14. In a method performed by a base station, Transmit configuration information related to uplink precoding; and It includes receiving a precoded uplink signal based on the above setting information, and The resources for the uplink signal include one or more frequency resource units and one or more time resource units, and A method in which the uplink signal is precoded based on precoder cycling for at least one of each frequency resource unit and / or each time resource unit.

15. Regarding base stations, At least one processor; and It includes at least one memory configured to store instructions that cause the at least one processor to perform operations by being executed by the at least one processor, and The operations of the above processor are, Transmit configuration information related to uplink precoding; and It includes receiving a precoded uplink signal based on the above setting information, and The resources for the uplink signal include one or more frequency resource units and one or more time resource units, and The above uplink signal is a base station that is precoded based on precoder cycling for at least one of each frequency resource unit and / or each time resource unit.

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