Apparatus and method for utilizing synchronization signal and physical broadcast channel block transmitted on demand in wireless communication system

Abstract

The purpose of the present disclosure is to utilize a synchronization signal / physical broadcast channel block (SSB) transmitted on demand in a wireless communication system, and a method therefor may comprise the steps of: receiving configuration information related to a transmission configuration indication (TCI), wherein the configuration information includes a first signal as information related to quasi-colocation (QCL); receiving a second signal on a first cell; and receiving a downlink signal or channel on the first cell by applying QCL assumption of the second signal, wherein the second signal may include an on-demand SSB on the first cell.

Description

Device and method for utilizing synchronous signals and physical broadcast channel blocks transmitted on-demand in a wireless communication system

[0001] The following description relates to a wireless communication system, and to a device and method for utilizing an SSB (synchronization signal / physical broadcast channel block) transmitted on-demand in a wireless communication system.

[0002] The 5G mobile communications system, the successor to LTE (long-term evolution), is a new, clean-slate mobile communications system characterized by high performance, low latency, and high availability. 5G NR can utilize all available spectrum resources, from low-frequency bands below 1 GHz, to mid-frequency bands between 1 GHz and 10 GHz, and to high-frequency bands (e.g., millimeter wave) above 24 GHz. 6G systems are being developed based on the underlying technologies of 5G mobile communications.

[0003] The 6G system aims to provide (i) very high data rates per device, (ii) a very large number of connected devices, (iii) global connectivity, (iv) very low latency, (v) low energy consumption for battery-free Internet of Things (IoT) devices, (vi) ultra-reliable connectivity, and (vii) connected intelligence with machine learning capabilities. The vision of the 6G system can be divided into four aspects: intelligent connectivity, deep connectivity, holographic connectivity, and ubiquitous connectivity.

[0004] The present disclosure relates to a device and method for effectively utilizing a synchronization signal / physical broadcast channel block (SSB) transmitted on-demand in a wireless communication system.

[0005] The present disclosure relates to a device and method for effectively supporting a network energy saving (NES) operation of a base station in a wireless communication system.

[0006] The present disclosure relates to a device and method for obtaining time synchronization using on-demand SSB in a wireless communication system.

[0007] The present disclosure relates to a device and method for estimating path-loss using on-demand SSB in a wireless communication system.

[0008] The present disclosure relates to a device and method for setting information related to quasi-colocated (QCL) using on-demand SSB in a wireless communication system.

[0009] The present disclosure relates to a device and method for setting information related to a transmission configuration indicator (TCI) using on-demand SSB in a wireless communication system.

[0010] The present disclosure relates to a device and method for adaptively applying a QCL source depending on a situation related to on-demand SSB in a wireless communication system.

[0011] The present disclosure relates to a device and method for selectively using lists related to TCI depending on a situation related to on-demand SSB in a wireless communication system.

[0012] The present disclosure relates to a device and method for adaptively interpreting information related to a TCI state depending on a situation related to on-demand SSB in a wireless communication system.

[0013] The present disclosure relates to a device and method for performing channel state information (CSI) reporting using on-demand SSB in a wireless communication system.

[0014] The technical objectives to be achieved in the present disclosure are not limited to those mentioned above, and other technical tasks not mentioned can be considered by a person having ordinary skill in the technical field to which the technical configuration of the present disclosure is applied from the embodiments of the present disclosure described below.

[0015] As an example of the present disclosure, the method includes the steps of receiving configuration information related to a transmission configuration indication (TCI), the configuration information including information related to a quasi-colocated (QCL) of a first signal, receiving a second signal on a first cell, and receiving a downlink signal or channel on the first cell by applying a QCL assumption of the second signal, wherein the second signal may include an on-demand synchronization signal / physical broadcast channel block (SSB) on the first cell.

[0016] As an example of the present disclosure, the method includes the steps of transmitting configuration information related to a transmission configuration indication (TCI), the configuration information including information related to a quasi-colocated (QCL) of a first signal, and transmitting a downlink signal or channel on the first cell by applying a QCL assumption of the second signal based on transmission of the second signal on the first cell, wherein the second signal may include an on-demand synchronization signal / physical broadcast channel block (SSB) on the first cell.

[0017] As an example of the present disclosure, a device includes a transceiver and a processor connected to the transceiver, the processor configured to receive configuration information related to a transmission configuration indication (TCI), the configuration information including information related to a quasi-colocated (QCL) of a first signal, receive a second signal on a first cell, and receive a downlink signal or channel on the first cell by applying a QCL assumption of the second signal, wherein the second signal may include an on-demand synchronization signal / physical broadcast channel block (SSB) on the first cell.

[0018] As an example of the present disclosure, a device includes a transceiver and a processor connected to the transceiver, wherein the processor is configured to transmit configuration information related to a transmission configuration indication (TCI), wherein the configuration information includes information related to a quasi-colocated (QCL) of a first signal, and transmit a downlink signal or channel on a first cell by applying a QCL assumption of the second signal based on transmission of a second signal on the first cell, wherein the second signal may include an on-demand synchronization signal / physical broadcast channel block (SSB) on the first cell.

[0019] As an example of the present disclosure, a terminal includes at least one processor, and at least one memory connected to the at least one processor and storing instructions that, when executed by the at least one processor, cause the terminal to perform operations, the operations including: receiving configuration information related to a transmission configuration indication (TCI), the configuration information including a first signal as information related to a quasi-colocated (QCL) signal, receiving a second signal on a first cell, and receiving a downlink signal or channel on the first cell by applying a QCL assumption of the second signal, wherein the second signal may include an on-demand synchronization signal / physical broadcast channel block (SSB) on the first cell.

[0020] As an example of the present disclosure, a non-transitory computer-readable medium storing at least one program instruction, wherein the at least one program instruction, when executed by at least one processor, causes a terminal to perform operations, the operations including: receiving configuration information related to a transmission configuration indication (TCI), the configuration information including a first signal as information related to a quasi-colocated (QCL) signal, receiving a second signal on a first cell, and receiving a downlink signal or channel on the first cell by applying a QCL assumption of the second signal, wherein the second signal may include an on-demand synchronization signal / physical broadcast channel block (SSB) on the first cell.

[0021] The above-described aspects of the present disclosure are only some of the preferred embodiments of the present disclosure, and various embodiments reflecting the technical features of the present disclosure can be derived and understood by a person having ordinary skill in the art based on the detailed description of the present disclosure to be described below.

[0022] The following effects may be achieved by embodiments based on the present disclosure.

[0023] According to the present disclosure, various functions can be effectively performed using on-demand SSB (synchronization signal / physical broadcast channel block).

[0024] The effects that can be obtained from the embodiments of the present disclosure are not limited to the effects mentioned above, and other effects not mentioned can be clearly derived and understood by those skilled in the art to which the technical configuration of the present disclosure is applied, from the description of the embodiments of the present disclosure below. In other words, unintended effects resulting from implementing the configuration described in the present disclosure can also be derived from the embodiments of the present disclosure by those skilled in the art.

[0025] Figure 1 illustrates an example of a flexible network topology applicable to the present disclosure.

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

[0027] FIG. 3 illustrates an example of a wireless device applicable to the present disclosure.

[0028] FIG. 4 illustrates an example of a communication procedure between a first node and a second node applicable to the present disclosure.

[0029] FIG. 5 illustrates an example of an operation procedure of a base station supporting network energy saving (NES) technology applicable to the present disclosure.

[0030] FIG. 6 illustrates an example of a procedure for a carrier aggregation (CA) operation using a synchronization signal / physical broadcast channel block (SSB)-less SCell (secondary cell) applicable to the present disclosure.

[0031] FIGS. 7A to 7C illustrate examples of on-demand system information transmission methods applicable to the present disclosure.

[0032] Figure 8 illustrates examples of beams that can be applied to the present disclosure.

[0033] FIG. 9 illustrates an example of a DL BM (downlink beam management) procedure using a synchronization signal block (SSB) applicable to the present disclosure.

[0034] FIG. 10 illustrates an example of a DL BM procedure using CSI (channel state information)-RS (reference signal) that can be applied to the present disclosure.

[0035] FIG. 11 illustrates an example of a terminal reception beam determination procedure applicable to the present disclosure.

[0036] Figure 12 illustrates an example of a transmission beam determination procedure of a base station applicable to the present disclosure.

[0037] Figure 13 illustrates an example of resource allocation in the time and frequency domains that can be applied to the present disclosure.

[0038] FIG. 14 illustrates an example of beam sweeping for UL BM (uplink beam management) using SRS (sounding reference signal) applicable to the present disclosure.

[0039] FIG. 15 illustrates an example of a UL BM procedure using SRS that can be applied to the present disclosure.

[0040] Figure 16 is a flowchart showing an example of a CSI-related procedure.

[0041] FIG. 17 illustrates examples of frequency bands operated by a base station according to one embodiment of the present disclosure.

[0042] FIG. 18 illustrates an example of a procedure for utilizing on-demand SSB in a wireless communication system according to one embodiment of the present disclosure.

[0043] FIG. 19 illustrates an example of a procedure for performing time synchronization of an SSB-less cell in a wireless communication system according to one embodiment of the present disclosure.

[0044] FIG. 20 illustrates an example of a procedure for performing time synchronization of an SSB-less cell in a wireless communication system according to one embodiment of the present disclosure.

[0045] FIG. 21 illustrates an example of a procedure for setting a parameter indicating channel relevance of an SSB-less cell in a wireless communication system according to one embodiment of the present disclosure.

[0046] FIG. 22 illustrates an example of a procedure for receiving a signal using QCL assumption in a wireless communication system according to one embodiment of the present disclosure.

[0047] FIG. 23 illustrates an example of a procedure for applying a channel correlation parameter based on a QCL source in a wireless communication system according to one embodiment of the present disclosure.

[0048] FIG. 24 illustrates an example of a procedure for utilizing on-demand SSB in an SSB-less cell in a wireless communication system according to one embodiment of the present disclosure.

[0049] In this disclosure, "A or B" can mean "only A," "only B," or "both A and B." In other words, "A or B" in this disclosure can be interpreted as "A and / or B." For example, "A, B or C" in this disclosure can mean "only A," "only B," "only C," or "any combination of A, B and C."

[0050] As used herein, a slash ( / ) or a comma 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."

[0051] In the present disclosure, “at least one of A and B” may mean “only A,” “only B,” or “both A and B.” Additionally, in the present disclosure, the expressions “at least one of A or B” or “at least one of A and / or B” may be interpreted identically to “at least one of A and B.”

[0052] Additionally, in the present disclosure, “at least one of A, B and C” can mean “only A,” “only B,” “only C,” or “any combination of A, B and C.” Additionally, “at least one of A, B or C” or “at least one of A, B and / or C” can mean “at least one of A, B and C.”

[0053] Additionally, parentheses used in the present disclosure may mean "for example." Specifically, when "control information (ABC)" is indicated, "ABC" may be described as an example of "control information." For example, "control information" may include DEF as another example. In other words, the "control information" of the present disclosure is not limited to "ABC," and "ABC" may be described as an example of "control information." Furthermore, even when indicated as "control information (i.e., ABC)," "ABC" may be described as an example of "control information."

[0054] Additionally, in the present disclosure, terms such as “first,” “second,” etc. are used only for the purpose of distinguishing one component from another and are not used to limit the components, and do not limit the order or importance between the components unless specifically limited. Accordingly, a first component in one embodiment of the present disclosure may be referred to as a second component in another embodiment, and similarly, a second component in one embodiment may be referred to as a first component in another embodiment.

[0055] In the following explanation, ‘when, if, in case of’ can be replaced with ‘based on’.

[0056] Technical features individually described in one drawing in this disclosure may be implemented individually or simultaneously.

[0057] In the present disclosure, a terminal is a user equipment (UE) or a consumer-side device, and may also be referred to as a base station / second node / IAB (integrated access and backhaul) node / first node that receives / transmits signals from / to a Transmission-Reception Point (TRP). The terminal may correspond to a physical node or a logical node. The terminal may correspond to an endpoint on the user side, or may correspond to an intermediate point between other endpoints. In communication between two points that are not limited to endpoints (including one-to-one / many-to-one / one-to-many / many-to-many communication), the terminal may correspond to a served node. A terminal may be a node with a fixed location, or a node with an unfixed location (or mobile).

[0058] In the present disclosure, a base station (BS) is a device on the network side, and may also be called a second node / IAB node / x-NodeB (x-NodeB, x may be an abbreviation related to a 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 may correspond to an intermediate point between other endpoints. In communication between two points that are 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 unfixed location.

[0059] In the present disclosure, higher layer parameters may be set for the terminal, preset, or predefined. For example, the base station may transmit higher layer parameters to the terminal. For example, the terminal may transmit parameters such as capabilities to the base station as higher layer parameters. For example, the higher layer parameters may be transmitted via radio resource control (RRC) signaling or medium access control (MAC) signaling.

[0060] In the present disclosure, the information / state / parameter being “configured or pre-configured” can be interpreted as the information / state / parameter being provided / pre-provided to the terminal through pre-defined signaling (e.g., SIB, MAC, RRC) from the base station. In the present disclosure, the information / state / parameter being “defined or pre-defined” can be interpreted as the information / state / parameter being known in advance or pre-stored at the base station and the terminal without signaling between the base station and the terminal.

[0061] The technology described in the present disclosure can be used in various wireless communication systems such as code division multiple access (CDMA), frequency division multiple access (FDMA), time division multiple access (TDMA), orthogonal frequency division multiple access (OFDMA), and single carrier frequency division multiple access (SC-FDMA). CDMA can be implemented with wireless technologies such as universal terrestrial radio access (UTRA) or CDMA2000. TDMA can be implemented with wireless technologies such as global system for mobile communications (GSM) / general packet radio service (GPRS) / enhanced data rates for GSM evolution (EDGE). OFDMA can be implemented with wireless technologies such as Institute of Electrical and Electronics Engineers (IEEE) 802.11 (Wi-Fi), IEEE 802.16 (WiMAX), IEEE 802-20, evolved UTRA (E-UTRA), long term evolution (LTE), and 5G NR.

[0062] The technology described in the present disclosure can be implemented with 6G wireless technology and applied to various 6G systems. For example, the 6G system can have key factors such as enhanced mobile broadband (eMBB), ultra-reliable low latency communications (URLLC), massive machine-type communication (mMTC), artificial intelligence (AI) integrated communication, tactile internet, high throughput, high network capacity, high energy efficiency, low backhaul and access network congestion, and enhanced data security.

[0063] A. 6G network architecture

[0064] Figure 1 illustrates an example of a flexible network topology applicable to the present disclosure.

[0065] To compensate for incomplete network coverage areas, a network topology that allows for more flexible and resilient split radio access networks (RANs) may be considered. For this purpose, various nodes, such as IAB nodes, relays, and RF repeaters, as illustrated in the example in Figure 1, may be applied, or a non-terrestrial network (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, or 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 simply performs the function of signal amplification and forwarding, while a network-controlled repeater may not only amplify and forward signals but also adjust transmission and reception settings based on information provided by the network. For example, an NTN node may correspond to a satellite or aircraft that provides NTN coverage that terrestrial networks find difficult to provide. In addition to these examples, various intermediate points can be introduced to improve the network topology.

[0066] Referring to Figure 1, a split RAN can support the division of a base station into a centralized unit (CU) and one or more distributed units (DUs). The CU and DU can correspond to logical units. The CU can 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 DUs, various intermediate points can be introduced to compensate for this.

[0067] An intermediate point may correspond to a terminal or a base station, depending on its relationship to other nodes. For example, an IAB node may include a mobile-termination (MT) portion and a unit (DU). The MT may connect the IAB node to a donor node. The unit (DU) of an IAB node may serve other terminals or connect to other IAB nodes to provide multi-hop wireless backhaul to the terminal. In other words, an IAB node may correspond to a base station in its relationship to a user-side node, and to a terminal in its relationship to a network-side node.

[0068] In some examples of the present disclosure, the description of a terminal may equally apply not only to a user-side endpoint, but also to an intermediate point corresponding to a terminal in a relative relationship with a network-side endpoint. Similarly, in some examples of the present disclosure, the description of a base station may equally apply not only to a network-side endpoint, but also to an intermediate point corresponding to a base station in a relative relationship with a user-side endpoint. However, in most cases where there is no additional description of the operations of three or more entities, the communicating entities in the present disclosure are briefly described as terminals and / or base stations (or first nodes and / or second nodes), and the terms terminal and / or base stations (or first nodes and / or second nodes) are interpreted to include / replace any endpoint or any intermediate point in relation to other nodes.

[0069] That is, in some examples of the present disclosure, for the sake of simplicity of explanation, the subjects of the operation may be referred to as a base station and / or a terminal (or a first node and / or a second node). In addition, the terms base station and / or terminal (or a first node and / or a second node) may also be interpreted / replaced as in the following examples: For example, the base station (or a first node) and the terminal (or a second node) may respectively correspond to a first endpoint and a second endpoint; may respectively correspond to an endpoint and an intermediate point; may respectively correspond to an intermediate point and an endpoint; or may respectively correspond to a first intermediate point and a second intermediate point.

[0070] In the present disclosure, there may be zero or more intermediate points between the base station and the terminal. If intermediate points exist, they may be IAB nodes / relays / RF repeaters / NTN (non-terrestrial network) nodes, or nodes supporting other functions. The intermediate points may be nodes with fixed locations or nodes with unfixed locations.

[0071] Systems applicable to this disclosure

[0072] FIG. 2 illustrates an example of a structure of a wireless communication system applicable to the present disclosure. The communication system (100) of FIG. 2 applicable to the present disclosure 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 a 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 Things) device (110f), and an AI (artificial intelligence) device / server (110g). For example, the vehicle may include a vehicle equipped with a wireless communication function, an autonomous vehicle, a vehicle capable of performing vehicle-to-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, a digital signage, a vehicle, a robot, etc. The portable device (110d) may include a smartphone, a smart pad, a wearable device (e.g., a smart watch, smart glasses), a computer (e.g., a laptop, etc.), 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 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 act as a network device (120) to another wireless device (110).

[0073] Wireless devices (110a to 110f) can be connected to a network (130) via a network device (120). AI technology can be applied to the wireless devices (110a to 110f), and the wireless devices (110a to 110f) can be connected to an AI server (110g) via a network (130). The network (130) can be configured using a 3G network, a 4G (e.g., LTE) network, a 5G (e.g., NR), or a 6G network. The wireless devices (110a to 110f) can communicate with each other via the network device (120) / network (130), but can 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). Additionally, an IoT device (110f) (e.g., a sensor) can communicate directly with other IoT devices (e.g., sensors) or other wireless devices (110a to 110f).

[0074] Wireless communication / connection (150a, 150b, 150c) can be established between wireless devices (110a to 110f) / network devices (120), network devices (120) / network devices (120). Here, the 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 the wireless communication / connection (150a, 150b, 150c), the wireless device and the network device / wireless device, and the network device and the network device can transmit / receive wireless signals to each other. For example, the wireless communication / connection (150a, 150b, 150c) can transmit / receive signals through various physical channels. To this end, based on various descriptions of the present disclosure, at least some of various configuration information setting processes for transmitting / receiving wireless signals, various signal processing processes (e.g., channel encoding / decoding, modulation / demodulation, resource mapping / demapping, etc.), resource allocation processes, etc. may be performed.

[0075] Devices applicable to the present disclosure

[0076] FIG. 3 illustrates an example of a wireless device applicable to the present disclosure.

[0077] Referring to FIG. 3, the wireless device (200) can transmit and receive wireless signals via 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).

[0078] 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 operational flowcharts disclosed in this document. For example, the processor (202) may process information in the memory (204) to generate first information / signal, and then transmit a wireless signal including the first information / signal via the transceiver (206). In addition, the processor (202) may receive a wireless signal including second information / signal via the transceiver (206), and then store information obtained from 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, the memory (204) may store software code including 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 operational flowcharts disclosed herein. Here, the processor (202) and the memory (204) may be part of a communication modem / circuit / chip designed to implement wireless communication technology. The transceiver (206) may be connected to the processor (202) and may transmit and / or receive wireless signals via at least one antenna (208). The transceiver (206) may include a transmitter and / or a receiver. The transceiver (206) may be used interchangeably with an RF (radio frequency) unit. In the present disclosure, a wireless device may also mean a communication modem / circuit / chip.

[0079] Hereinafter, the 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., a functional layer such as physical (PHY), media access control (MAC), radio link control (RLC), packet data convergence protocol (PDCP), radio resource control (RRC), and service data adaptation protocol (SDAP)). At least one processor (202) may generate at least one Protocol Data Unit (PDU) and / or at least one Service Data Unit (SDU) according to the descriptions, functions, procedures, proposals, methods, and / or operation flowcharts disclosed in this document. At least one processor (202) may generate a message, control information, data, or information according to the descriptions, functions, procedures, proposals, methods, and / or operation flowcharts disclosed in this document. At least one processor (202) can generate a signal (e.g., a baseband signal) including a PDU, an SDU, a message, control information, data or information according to the functions, procedures, proposals and / or methods disclosed in this document, and provide the signal to at least one transceiver (206). At least one processor (202) can receive a signal (e.g., a baseband signal) from at least one transceiver (206) and obtain the PDU, SDU, message, control information, data or information according to the descriptions, functions, procedures, proposals, methods and / or operational flowcharts disclosed in this document.

[0080] At least one processor (202) may be referred to as a controller, a microcontroller, a microprocessor, or a microcomputer. The 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 the at least one processor (202). The descriptions, functions, procedures, proposals, methods, and / or operation flowcharts 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. The descriptions, functions, procedures, proposals, methods, and / or operation flowcharts disclosed in this document may be included in the at least one processor (202), or may be stored in at least one memory (204) and driven by the at least one processor (202). The descriptions, functions, procedures, suggestions, 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.

[0081] At least one memory (204) can be connected to at least one processor (202) and can store various forms of data, signals, messages, information, programs, codes, instructions and / or commands. The at least one memory (204) can be configured as a read only memory (ROM), a random access memory (RAM), an erasable programmable read only memory (EPROM), a flash memory, a hard drive, a register, a cache memory, a computer readable storage medium and / or a combination thereof. The at least one memory (204) can be located internally and / or externally to the at least one processor (202). In addition, the at least one memory (204) can be connected to the at least one processor (202) via various technologies such as a wired or wireless connection.

[0082] At least one transceiver (206) can transmit user data, control information, wireless signals / channels, etc., mentioned in the methods and / or flowcharts of this document to at least one other device. At least one transceiver (206) can receive user data, control information, wireless signals / channels, etc. mentioned in the descriptions, functions, procedures, proposals, methods and / or flowcharts disclosed in this document from at least one other device. For example, at least one transceiver (206) can be connected to at least one processor (202) and can transmit and receive wireless signals. For example, at least one processor (202) can control at least one transceiver (206) to transmit user data, control information, or wireless signals to at least one other device. Furthermore, at least one processor (202) can control at least one transceiver (206) to receive user data, control information, or wireless signals from at least one other device. In addition, 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. mentioned in the descriptions, functions, procedures, proposals, methods and / or operation flowcharts 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).For this purpose, at least one transceiver (206) may include an (analog) oscillator and / or filter.

[0083] The components of the wireless device described with reference to FIG. 3 may be referred to by different terms in terms of functionality. For example, the processor (202) may be referred to as a control unit, the transceiver (206) as a communication unit, and the memory (204) as a storage unit. In some cases, the communication unit may be used to mean at least a portion of the processor (202) and the transceiver (206).

[0084] The structure of the wireless device described with reference to FIG. 3 can be understood as the structure of at least a portion of various devices. For example, the structure of the wireless device illustrated in FIG. 3 can be at least a portion of various devices described with reference to FIG. 2 (e.g., a robot (110a), a vehicle (110b-1, 110b-2), an XR device (110c), a portable device (110d), a home appliance (110e), an IoT device (110f), an AI device / server (110g)). Furthermore, according to various embodiments, in addition to the components illustrated in FIG. 3, the device may further include other components.

[0085] For example, the device may be a portable device such as a smartphone, a smart pad, a wearable device (e.g., a smart watch, smart glasses), or a portable computer (e.g., a 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., an audio input / output port, a video input / output port), and an input / output unit for inputting and outputting image information / signals, audio information / signals, data, and / or information input from a user.

[0086] For example, the device may be a mobile device such as a mobile robot, a vehicle, a train, an aerial vehicle (AV), a ship, etc. In this case, the device may further include at least one of a driving unit including at least one of an engine, a motor, a power train, wheels, brakes, and a steering unit of the device, a power supply unit including a wired / wireless charging circuit, a battery, etc. that supplies power, a sensor unit that senses status 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 obtains location information of the mobile device through a global positioning system (GPS) and various sensors.

[0087] For example, the device may be an XR device such as an HMD, a head-up display (HUD) installed in a vehicle, a television, a smartphone, a computer, a wearable device, a home appliance, a 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 obtains control information, data, etc. from the outside and outputs the generated XR object, and a sensor unit that senses status information, environmental information, and user information of the device or the surroundings of the device.

[0088] For example, the device may be a robot that can be classified into industrial, medical, household, military, etc. types 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 status information, environmental information, and user information of the device or its surroundings, and a driving unit that performs various physical actions, such as moving the robot joints.

[0089] For example, the device may be an AI device such as a TV, a projector, a smartphone, a PC, a laptop, a digital broadcasting terminal, a tablet PC, a wearable device, a set-top box (STB), a radio, a washing machine, a refrigerator, digital signage, a robot, a 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 status information, environmental information, and user information of the device or its surroundings, and a training unit that trains a model composed of an artificial neural network using learning data.

[0090] The structure of the wireless device illustrated in FIG. 3 may be understood as a part of a terminal (or first node), or as a part of an intermediate point, or as a part of a base station (or second node). If the device illustrated 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 communications. However, if the front haul and / or back haul communications are based on wireless communications, at least one transceiver (206) illustrated in FIG. 3 may be used for front haul and / or back haul communications, and a wired transceiver may not be included.

[0091] B. Communication Procedures

[0092] FIG. 4 illustrates an example of 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. The second node of FIG. 1 supports dynamic spectrum sharing (DSS) to provide connectivity to both nodes implementing 6G technology and nodes implementing pre-6G wireless communication technologies (e.g., 5G, 4G). That is, the first node of FIG. 1 may implement 6G technology or pre-6G wireless communication technologies (e.g., 5G, 4G). In addition, the first node and / or the second node may support a full duplex mode as well as a non-overlapping full duplex mode.

[0093] 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 operations of transmitting and / or receiving data by the terminal (440) and the base station (420) and operations performed prior thereto are illustrated. However, the operations of Fig. 1 are not limited to operations between the terminal and the base station, and may be interpreted as operations between the first node and the second node. In addition, although Fig. 1 illustrates direct wireless signal transmission and reception operations between the terminal (440) and the base station (420), one or more intermediate points may exist between the terminal (440) and the base station (420), and wireless signals may be transmitted and received via one or more intermediate points.

[0094] Referring to FIG. 4, in step 401, the terminal (440) and the base station (420) perform synchronization. For example, the terminal (440) performs an initial cell search operation. Specifically, the terminal (440) can detect a synchronization signal for connection to at least one base station transmitted from the base station (420) according to a predefined rule. Here, the synchronization signal can include a plurality of synchronization signals classified according to structure or purpose (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 (440) can confirm the boundary of a unit (e.g., a frame, a subframe, a slot, and / or a symbol) constituting a wireless signal transmission of the base station (420) and obtain information (e.g., a cell identifier) ​​about the base station (420).

[0095] In step 403, the terminal (440) obtains system information transmitted from the base station (420). The system information is information related to the properties, characteristics, and / or capabilities of the base station (420) required to access the base station (420) and use the service, and may be classified according to the content (e.g., whether it is essential for access), transmission structure (e.g., channel used, whether provided on-demand), etc., and may be classified into, for example, first system information (e.g., master information block (MIB), primary system information), second system information (e.g., system information block (SIB), secondary system information), etc. If necessary, the terminal (440) may transmit a signal requesting system information before receiving the system information. However, the request and provision of the system information may be performed after the random access procedure described below.

[0096] In step 405, the terminal (440) and the base station (420) perform a random access procedure. The terminal (440) may transmit and / or receive at least one message (e.g., a random access preamble, a random access response (RAR) message, etc.) for the random access procedure based on information related to a channel for the random access procedure of the base station (420) obtained through system information (e.g., a channel position, a channel structure, a structure of a supported preamble, etc.). For example, the terminal (440) may transmit a first message (e.g., a preamble, MSG1) through the channel for the random access procedure, receive a second message (e.g., an RAR message, MSG2), transmit a third message (e.g., MSG3) including information related to the terminal (440) (e.g., identification information) to the base station (420) 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 and third messages may be sent and received as one message, or the second and fourth messages may be sent and received as one message.

[0097] In step 407, the terminal (440) and the base station (420) perform signaling of control information. Here, the control information may be defined in various layers, such as a layer that controls a connection (e.g., a radio resource control (RRC) layer), a layer that handles mapping between logical channels and transport 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 (440) and the base station (420) may perform at least one of signaling for establishing a connection, signaling for determining settings related to communication, and signaling for indicating allocated resources.

[0098] In step 409, the terminal (440) and the base station (420) transmit and / or receive data. In other words, the terminal (440) and the base station (420) can process, transmit, and / or receive data based on the signaling of the control information. For example, when transmitting data, the terminal (440) or the base station (420) 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 (440) or the base station (420) can perform at least one of signal extraction from resources, waveform demodulation for each antenna, signal arrangement considering layer mapping, constellation demapping, descrambling, and channel decoding.

[0099]

[0100] C. NES (network energy saving)

[0101] Energy conservation at base stations is a key consideration in wireless communication systems, including 3GPP, as it can contribute to building eco-friendly networks by reducing carbon emissions and reducing operational expenditures (OPEX) for telecommunications companies. In particular, the introduction of 5G communications will require higher transmission rates, necessitating base stations to be equipped with more antennas and provide services across wider bandwidths and frequency bands. Consequently, recent studies have shown that base station energy costs have reached as high as 20% of total OPEX. Accordingly, 5G systems are adopting various technologies to reduce energy consumption, known as network energy savings (NES), and the standardization of related technologies is expected to continue. Specifically, the following techniques were discussed in the recent Rel-18.

[0102] -----------------------------------------------------------------------

[0103] 1. If deemed feasible by RAN4 studies, specify SSB-less SCell operation for interband CA for FR1 and co-located cells, where the UE measures SSB transmitted on the PCell or another SCell for SCell time / frequency synchronization (including downlink AGC) and L1 / L3 measurements, including potential enhancements to the SCell activation procedure if required. [RAN4, RAN2]]

[0104] 2. Embody improvements to the cell DTX / DRX mechanism, including inter-node information exchange for cell DTX / DRX and alignment of cell DTX / DRX and UE DRX in RRC_CONNECTED mode. [RAN2, RAN1, RAN3]

[0105] ·Note: No changes to SSB transmission due to cell DTX / DRX.

[0106] ·Note: The above improvements should avoid any impact on IDLE / INACTIVE UEs.

[0107] 3. Implement the following technologies in the space and power domains:

[0108] · To enable efficient adaptation of spatial elements (e.g., antenna ports, active transceiver chains), specify necessary improvements to CSI and beam management-related procedures, including measurement and reporting, and signaling. [RAN1, RAN2]

[0109] · To enable efficient adaptation of power offset values ​​between PDSCH and CSI-RS, necessary improvements to CSI-related procedures, including measurement, reporting, and signaling, are specified. [RAN1, RAN2]

[0110] · Note: The above goals are only applicable to UE specific channels / signals.

[0111] · Note: Given the total number and requirements of CSI reports, conventional UE CSI / CSI-RS capabilities apply.

[0112] 4. If necessary, specify a mechanism to prevent camping of legacy UEs in cells adopting Rel-18 NES technology. [RAN2]

[0113] 5. Implement improvements to the CHO procedure when the source / target cell is in NES mode. [RAN2]

[0114] 6. Improvements to limit paging in limited areas and specify inter-node beam activation [RAN3].

[0115] 7. If necessary, specify the RRM / RF core requirements for the above features. [RAN4]

[0116] -----------------------------------------------------------------------

[0117] According to the application of NES technology, the base station can perform operations such as controlling on / off for a certain duration in the time domain, controlling transmission / reception resources for UE-common or UE-specific signals / channels, changing the amount of frequency domain resources, controlling transmission power, or turning on / off antenna ports, transmission-reception points (TRPs), etc. in the spatial domain. Fig. 5 illustrates an example of an operation procedure of a base station supporting the NES technology applicable to the present disclosure. Referring to Fig. 5, the base station identifies the NES solution(s) to be applied. The NES solution(s) may be related to control of signal transmission / reception (e.g., on / off), beam operation, handover procedure, channel measurement and reporting, etc. Which NES solution(s) to apply can be adaptively selected or predefined depending on the current situation (e.g., cell load level, characteristics of connected terminals, etc.). The base station, having identified the NES solution(s), performs signaling for the NES. The specific signaling procedure may vary depending on the identified NES solution(s). For example, the base station may transmit common information about the NES solution(s), transmit configuration information necessary for NES operation to at least one terminal, or transmit control information regarding the progress of the NES operation to at least one terminal. In addition, the base station may receive capability information related to the NES from at least one terminal. Thereafter, the base station performs operations for the NES. At this time, the base station may perform operations for the NES based on the previously performed signaling. That is, based on the system information, configuration information, and control information transmitted through the signaling, the base station may turn on / off the transmission / reception of a specific signal, turn on / off elements in the spatial domain, or adjust resources for the transmission / reception of a measurement signal.

[0118] Through a procedure similar to that in Fig. 5, NES technology can be implemented. Examples of NES solutions that can be implemented through a procedure similar to that in Fig. 5 are as follows.

[0119] · Intra-system energy saving solution: A RAN node can request a neighboring RAN node to switch at least one SSB beam into its inactive cell, or can perform paging using a limited set of beams to an inactive terminal (e.g., a stationary terminal).

[0120] · Inter-system energy saving solution: NG-RAN nodes that own capacity booster cells can autonomously transition those cells to an inactive state.

[0121] · SSB-less SCell solution: If SSB or SMTC (SSB-based RRM measurement timing configuration) configuration is not provided for the SCell, the UE can obtain the timing reference and AGC source from another serving cell. In FR1 or FR2, the base station can configure intra-band CA or inter-band CA including the SCell without SSB transmission, in which case the SSB / SIB transmission can be triggered by the WUS (wake-up signal) of the UE. Accordingly, since the period of common channels / signals such as SSB increases, the base station can stay in the sleep state for a longer time.

[0122] · Cell DTX / DRX (discontinuous transmission / discontinuous reception) solution: In order to reduce the downlink transmission / uplink reception activity time of a base station, a periodic cell DTX / DRX pattern (e.g., active and inactive periods) can be commonly set for terminals within a cell having the corresponding feature. Here, the cell DTX pattern and the cell DRX pattern can be separately set and activated, and up to two cell DTX / DRX patterns can be set per MAC entity. When cell DTX is set and activated, at least one of monitoring for SPS opportunities or monitoring PDCCH can be stopped during the cell DTX inactivity period. When cell DRX is set and activated, at least one of transmission on CG resources or SR transmission can be stopped during the cell DRX inactivity period. Cell DTX / DRX can be activated / deactivated via RRC signaling or L1 group common signaling.

[0123] · Parameters such as active duration and cycle may be configured for cell DTX / DRX. The active duration is the period during which the UE receives a PDCCH or SPS opportunity and waits to transmit SR or CG, and the cycle specifies the periodic repetition of the active duration and the inactive duration. When both cell DTX and cell DRX are configured, parameters such as active duration and cycle are common. If the base station recognizes an emergency call or a public safety-related service (e.g., MPS or MCS), the network may release or deactivate the cell DTX / DRX configuration so as not to affect the service. In addition, at least some overlap is required between the active duration of the connected mode DRX of the UE and the active duration of the cell DTX / DRX. For example, the connected mode DRX cycle of the UE may be a multiple of the cell DTX / DRX cycle, or vice versa.

[0124] · Conditional handover (CHO) solution: A CHO procedure is used when the UE determines whether to execute a handover while NES technology is applied (e.g., when the cell activates or deactivates cell DTX / DRX). In this case, the UE can use an NES-specific CHO event to initiate CHO to a candidate cell, and the reception of a DCI activating the CHO condition(s) set by the NES event indication can be applied as an additional triggering condition for this.

[0125] · Spatial and Power Domain Adaptation Solution: To support gNBs for transceiver muting and / or transmit power adaptation, a UE may be configured to report multiple CSI entries in a CSI report based on multiple sub-configurations. Each sub-configuration corresponds to a spatial domain adaptation pattern (e.g., a subset of available spatial elements) and / or a power offset between a data channel (e.g., PDSCH) and CSI-RS. Depending on the application of the spatial and power domain adaptation solution, the CSI configuration, measurement, and / or reporting behavior may be affected.

[0126] SCell without SSB

[0127] FIG. 6 illustrates an example of a procedure for a CA operation using an SSB-less SCell applicable to the present disclosure. Referring to FIG. 6, a base station transmits configuration information for an SCell to a terminal. That is, the base station transmits configuration information for CA to provide a service to the terminal through a CA operation. Here, the CA operation may be an intra-band CA or an inter-band CA. For example, the configuration information for an SCell may include information including information for adding an SCell (e.g., sCellToAddModList), and specifically, may include a cell index, a physical cell identifier, information related to DL-UL configuration, information related to BWP, information related to cell DTX / DRX, information related to downlink frequency (e.g., FrequencyInfoDL), etc. Then, the terminal may determine the configuration for the CA operation and perform communication using the PCell and SCell of the base station. At this time, the terminal may confirm that the SCell is an SSB-less SCell based on the information related to the downlink frequency included in the configuration information, and may check the related parameters. For example, the UE can determine that the SCell is an SSB-less SCell by checking for the presence of a parameter indicating that the SCell is an SSB-less SCell (e.g., SSBlessSCell), and can determine the timing reference and AGC source for the SCell based on information about the reference cell (e.g., referenceCell). In the case of Figure D03, the reference cell may be the PCell. Therefore, the UE can use the PCell as a timing reference and AGC source for communications on the SCell.

[0128]

[0129] In 3GPP NR release 19, a work item titled “Enhancements of network energy savings for NR” was additionally approved. Specifically, the following enhancement techniques are being considered in 3GPP NR release 19:

[0130] -----------------------------------------------------------------------

[0131] Objectives of SI (study item) or core part WI (work item) or test part WI

[0132] The objectives of WI are as follows:

[0133] 1. Specify procedures and signaling methods to support on-demand SSB SCell operation for both in-band and inter-band CA for UEs in connection mode set to CA. [RAN1 / 2 / 3 / 4]

[0134] · Specify the triggering method(s). (Select from UE uplink wake-up signaling using existing signals / channels, cell on / off indication via backhaul, and Scell ​​activation / deactivation signaling.)

[0135] · Note 1: On-demand SSB transmission can be used by the UE for minimum SCell time / frequency synchronization, L1 / L3 measurements, and SCell activation, and is supported for FR1 and FR2 in unshared spectrum.

[0136] 2. Study the procedures and signaling method(s) to support on-demand SIB1 for UEs in idle / inactive mode, as follows: [RAN1 / 2 / 3]

[0137] · Triggering method by uplink wake-up signal using existing signal / channel.

[0138] · Provide wake-up signal settings to the UE

[0139] - Note: Modification of SSB is not discussed in this goal.

[0140] · If necessary, exchange information between gNBs at least for setting up wake-up signals.

[0141] · Checkpoints for normative work in RAN#105

[0142] 3. Implement adaptation of common signal / channel transmission [RAN1 / 2 / 3 / 4]

[0143] · Adaptation of SSB in the time domain, e.g. periodic adaptation

[0144] · PRACH adaptation in the time domain

[0145] · Study adaptation of PRACH in the spatial domain, e.g., non-uniform PRACH resources per SSB, and implement if found to be beneficial.

[0146] - This study will be conducted only in the second quarter of 2024.

[0147] · Coordination of paging opportunities, including limiting paging opportunities in the time domain.

[0148] - Note: Paging delay time should not increase.

[0149] - Note: There should be no negative impact on existing UEs unless significant benefits are achieved.

[0150] 4. For the above features, specify the corresponding core requirements. [RAN4]

[0151] -----------------------------------------------------------------------

[0152] On-demand SSB

[0153] Objective 1 discussed above discusses a method to reduce energy consumption by having the base station transmit SSB on a specific cell through the on-demand SSB process and not transmit SSB on the cell when there is no on-demand SSB process. In the existing NR system, SSB must be transmitted periodically and constantly for purposes such as time / frequency synchronization or RRM measurement, making it difficult to reduce energy consumption even when the base station has no data to receive or send. Considering this, the base station can reduce base station energy consumption by not performing SSB transmission until the on-demand SSB process is involved and then performing SSB transmission. The on-demand SSB process can be triggered using one of the following methods:

[0154] 1) The terminal requests SSB transmission from the base station by transmitting an uplink signal / channel (e.g., PRACH, PUCCH, PUSCH, SRS in the NR system).

[0155] 2) Requesting SSB transmission from base station (or TRP) #1 to base station (or TRP) #2 through an interface between base stations (e.g., Xn interface in NR system) or backhaul signaling.

[0156] 3) Signaling whether SSB transmission is possible for the corresponding Scell ​​through Scell ​​activation / deactivation signaling.

[0157] Considering coexistence with existing NR terminals, Release 19 is limited to on-demand SSB operation for connected mode terminals and SCells. However, in future releases or next-generation communication systems, on-demand SSB operation (for SSB transmission on PCell) considering inactive or idle mode terminals or initially connected terminals may be defined. In addition, carrier aggregation (CA) including the SCell can be applied to both intra-band CA and inter-band CA, and the SSB on the SCell transmitted through the on-demand SSB process can be utilized for at least functionality such as time / frequency synchronization, L1 / L3 measurement, and SCell activation.

[0158] On-demand SIB1 transmission

[0159] Objective 2 above discusses a method to reduce energy consumption by having the base station transmit SIB1 for a specific cell through the on-demand SIB1 process and not transmit SIB1 for the cell when there is no on-demand SIB1 process. In the existing NR system, SIB1 containing system information, random access information, etc. for initial access or idle mode terminals to access a cell must be provided periodically, making it difficult to reduce energy consumption even when the base station has no data to receive or send. Considering this, the base station can reduce base station energy consumption by not performing SIB1 transmission until the on-demand SIB1 process is involved and then performing SIB1 transmission. The on-demand SIB1 process can trigger SIB1 transmission of the base station by the terminal transmitting an uplink signal / channel (e.g., PRACH in the NR system). Specifically, the following scenarios can be considered, but are not limited to the following scenarios.

[0160] 1) Scenario 1: When a terminal receives an SSB (and / or other downlink signal / channel) from a cell#1 as in FIG. 7a and recognizes that SIB1 is not transmitted on the cell#1, the terminal may trigger SIB1 transmission by transmitting a signal requesting SIB1 (hereinafter, referred to as a WUS, wake-up signal, for convenience in the present invention) based on information provided in the SSB (and / or other downlink signal / channel) and / or predetermined information. The base station receiving the WUS may transmit a specific DL signal / channel on cell#1 in response thereto, and may transmit SIB1 on cell#1 (or without transmitting the DL signal / channel).

[0161] 2) Scenario 2: As in Fig. 7b, a UE may attempt to camp on cell#2 when it receives an SSB (and / or other downlink signal / channel such as SIB1) from a cell#1 and recognizes that SIB1 is not transmitted on the corresponding cell#2. The UE may trigger SIB1 transmission for cell#2 by transmitting a signal (i.e., WUS) requesting SIB1 on cell#1 based on information provided in the received SSB (and / or other downlink signal / channel such as SIB1) and / or predetermined information. The base station receiving the WUS may transmit a specific DL signal / channel (on cell#1 or cell#2) in response thereto, and may transmit SIB1 for cell#2 on cell#1 or cell#2 (or without transmitting the DL signal / channel).

[0162] 3) Scenario 3: As in Fig. 7c, a UE may attempt to camp on cell#2 when it receives an SSB (and / or other downlink signal / channel such as SIB1) from a cell#1 and recognizes that SIB1 is not transmitted on the corresponding cell#2. The UE may trigger SIB1 transmission for cell#2 by transmitting a signal (i.e., WUS) requesting SIB1 on cell#2 based on information provided in the received SSB (and / or other downlink signal / channel such as SIB1) and / or predetermined information. The base station receiving the WUS may transmit a specific DL signal / channel (on cell#1 or cell#2) in response thereto, and may transmit SIB1 for cell#2 on cell#1 or cell#2 (or without transmitting the DL signal / channel).

[0163] Adaptation of common signal / channel transmissions

[0164] Through the above objective 3, a method for reducing energy consumption by having the base station adjust the transmission of common signals / channels such as SSB, PRACH, and paging can be discussed. As in the above objective 1, if SSB is completely turned off, the energy consumption of the base station can be significantly reduced. However, if there is no SSB that performs functions such as time / frequency synchronization or RRM measurement, stable operation for the cell may not be guaranteed from the perspective of the terminal. Considering this, energy saving effects of the base station can be obtained by changing the transmission pattern of the SSB according to the situation. For example, the transmission pattern of the SSB may include at least one of a transmission period, a period per SSB candidate index(es), the SSB candidate index(es) transmitted within one transmission period, or transmission power.

[0165] In the case of PRACH resources, for example, in the case of contention-based random access, since it is not known when the UE will transmit the PRACH, the base station always attempts to receive in the configured PRACH resources, which may result in high energy consumption. Considering this, the energy of the base station can be saved by controlling the amount of PRACH resources. For example, the amount of RACH resources can be controlled by controlling the period of the PRACH resources, or by controlling the amount of resources by pre-configuring PRACH resource sets #1 and #2 and indicating whether to turn on only one of the two sets or both sets, or by providing the corresponding RACH resource amount uniformly or non-uniformly for each SSB index.

[0166] In the case of paging, PF (paging frame) and / or PO (paging occasion) are distributed along the time axis within the existing DRX cycle or paging cycle, and the terminal attempts to receive paging from a specific PF and / or PO derived based on its ID. Accordingly, if the base station wants to transmit paging to multiple terminals simultaneously, the base station will have to wake up frequently and transmit paging. As a measure to reduce the base station energy consumption caused by this, it may be considered to place the PF and / or PO for paging reception as close to the time axis as possible, or to place frequency axis resources differently within the same time.

[0167]

[0168] E-1. Beam Management (BM)

[0169] BM procedures are L1 (layer 1) / L2 (layer 2) procedures for acquiring and maintaining a set of base station (e.g., gNB, TRP, etc.) and / or terminal (e.g., UE) beams that can be used for downlink (DL) and uplink (UL) transmission / reception, and may include the following procedures and terminology.

[0170] - Beam measurement: An operation in which a base station or UE measures the characteristics of a received beam-forming signal.

[0171] - Beam determination: An operation in which a base station or UE selects its own transmit beam (Tx beam) / receive beam (Rx beam).

[0172] - Beam sweeping: The operation of covering a spatial area using a transmit and / or receive beam over a predetermined time interval in a predetermined manner.

[0173] - Beam report: An operation in which a UE reports information about a beam-formed signal based on beam measurement.

[0174] The BM procedure can be divided into (1) a DL BM procedure using SS (synchronization signal) / PBCH (physical broadcast channel) Block or CSI-RS, and (2) a UL BM procedure using SRS (sounding reference signal).

[0175] Additionally, each BM procedure may include Tx beam sweeping to determine the Tx beam and Rx beam sweeping to determine the Rx beam.

[0176]

[0177]

[0178] The DL BM procedure may include (1) transmission of beamformed DL RSs (reference signals) (e.g., CSI-RS or SS Block (SSB)) of the base station and (2) beam reporting of the terminal.

[0179] Here, beam reporting may include preferred DL RS ID(identifier)(s) and corresponding L1-RSRP (Reference Signal Received Power).

[0180] The above DL RS ID may be an SSBRI (SSB Resource Indicator) or a CRI (CSI-RS Resource Indicator).

[0181] As shown in Figure 8, SSB beams and CSI-RS beams can be used for beam measurement. The measurement metric is L1-RSRP per resource / block. SSB can be used for coarse beam measurement, and CSI-RS can be used for fine beam measurement. SSB can be used for both Tx beam sweeping and Rx beam sweeping.

[0182] Rx beam sweeping using SSB can be performed by the UE changing the Rx beam for the same SSBRI across multiple SSB bursts, where one SS burst contains one or more SSBs, and one SS burst set contains one or more SSB bursts.

[0183]

[0184] <SSB를 이용한 DL BM>

[0185] Figure 9 is a flowchart showing an example of a DL BM procedure using SSB.

[0186] The configuration for beam report using SSB is performed during CSI / beam configuration in RRC connected state (or RRC connected mode).

[0187] - The terminal receives a CSI-ResourceConfig IE including a CSI-SSB-ResourceSetList including SSB resources used for BM from the base station (S910).

[0188] [Table 1] shows an example of CSI-ResourceConfig IE, and as shown in [Table 1], BM configuration using SSB is not defined separately, and SSB is set as a CSI-RS resource.

[0189]

[0190] In [Table 1], the csi-SSB-ResourceSetList parameter indicates a list of SSB resources used for beam management and reporting in one resource set. Here, the SSB resource set can be set to {SSBx1, SSBx2, SSBx3, SSBx4, ...}. The SSB index can be defined from 0 to 63. - The terminal receives an SSB resource from the base station based on the CSI-SSB-ResourceSetList (S920).

[0191] - When CSI-RS reportConfig related to reporting on SSBRI and L1-RSRP is set, the terminal reports (beam) the best SSBRI and its corresponding L1-RSRP to the base station (S930).

[0192] That is, when the reportQuantity of the above CSI-RS reportConfig IE is set to 'ssb-Index-RSRP', the terminal reports the best SSBRI and the corresponding L1-RSRP to the base station.

[0193] And, if the terminal sets the CSI-RS resource in the same OFDM symbol(s) as the SSB (SS / PBCH Block) and 'QCL-TypeD' is applicable, the terminal can assume that the CSI-RS and SSB are quasi co-located from the 'QCL-TypeD' perspective.

[0194] Here, the QCL TypeD may mean that the antenna ports are QCL-connected from a spatial Rx parameter perspective. When a terminal receives multiple DL antenna ports in a QCL Type D relationship, the same reception beam may be applied. In addition, the terminal does not expect the CSI-RS to be configured in an RE that overlaps with the SSB RE.

[0195]

[0196] <CSI-RS를 이용한 DL BM>

[0197] Regarding the usage of CSI-RS, i) if the repetition parameter is set to a specific CSI-RS resource set and TRS_info is not set, CSI-RS is used for beam management. ii) if the repetition parameter is not set and TRS_info is set, CSI-RS is used for TRS (tracking reference signal). iii) if the repetition parameter is not set and TRS_info is not set, CSI-RS is used for CSI acquisition.

[0198] This repetition parameter can only be set for CSI-RS resource sets associated with a CSI-ReportConfig that has a report of L1 RSRP or 'No Report (or None)'.

[0199] If a terminal is configured with a CSI-ReportConfig with reportQuantity set to 'cri-RSRP' or 'none', and a CSI-ResourceConfig (higher layer parameter resourcesForChannelMeasurement) for channel measurement does not include a higher layer parameter 'trs-Info' and includes an NZP-CSI-RS-ResourceSet with a higher layer parameter 'repetition' set, the terminal may be configured with only the same number of ports (1-port or 2-port) with the higher layer parameter 'nrofPorts' for all CSI-RS resources in the NZP-CSI-RS-ResourceSet.

[0200] (higher layer parameter) When repetition is set to 'ON', it is related to the Rx beam sweeping procedure of the terminal. In this case, when the terminal receives the NZP-CSI-RS-ResourceSet, the terminal can assume that at least one CSI-RS resource in the NZP-CSI-RS-ResourceSet is transmitted through the same downlink spatial domain transmission filter. That is, at least one CSI-RS resource in the NZP-CSI-RS-ResourceSet is transmitted through the same Tx beam. Here, at least one CSI-RS resource in the NZP-CSI-RS-ResourceSet can be transmitted in a different OFDM symbol. In addition, the terminal does not expect to receive different periods in periodicityAndOffset among all CSI-RS resources in the NZP-CSI-RS-Resourceset.

[0201] On the other hand, when Repetition is set to 'OFF', it is related to the Tx beam sweeping procedure of the base station. In this case, when repetition is set to 'OFF', the terminal does not assume that at least one CSI-RS resource in the NZP-CSI-RS-ResourceSet is transmitted through the same downlink spatial domain transmission filter. That is, at least one CSI-RS resource in the NZP-CSI-RS-ResourceSet is transmitted through a different Tx beam.

[0202] Figure 10 illustrates an example of a DL BM procedure using CSI-RS. Figure 10 (a) illustrates a terminal's Rx beam determination (or refinement) procedure, and Figure 10 (b) illustrates a base station's Tx beam sweeping procedure. Figure 10 (a) illustrates a case where the repetition parameter is set to 'ON', and Figure 10 (b) illustrates a case where the repetition parameter is set to 'OFF'.

[0203] Referring to Fig. 10 (a) and Fig. 11, the terminal's Rx beam determination process will be examined.

[0204] Figure 11 is a flowchart showing an example of a terminal's reception beam determination process.

[0205] - The terminal receives an NZP CSI-RS resource set IE including a higher layer parameter repetition from the base station via RRC signaling (S1110). Here, the repetition parameter is set to 'ON'.

[0206] - The terminal repeatedly receives resource(s) within the CSI-RS resource set with repetition 'ON' in different OFDM symbols through the same Tx beam (or DL ​​spatial domain transmission filter) of the base station (S1120).

[0207] - The terminal determines its own Rx beam (S1130).

[0208] - The terminal omits the CSI report (S1140). In this case, the reportQuantity of the CSI report config can be set to 'No report (or None)'.

[0209] That is, the terminal can omit the CSI report when repetition is set to 'ON'.

[0210] Referring to Fig. 10 (b) and Fig. 12, the Tx beam determination process of the base station is examined.

[0211] Figure 12 is a flowchart showing an example of a transmission beam determination process of a base station.

[0212] - The terminal receives an NZP CSI-RS resource set IE including a higher layer parameter repetition from the base station via RRC signaling (S1210). Here, the repetition parameter is set to 'OFF' and is related to the base station's Tx beam sweeping procedure.

[0213] - The terminal receives resources within the CSI-RS resource set with repetition set to 'OFF' through different Tx beams (DL spatial domain transmission filters) of the base station (S1220).

[0214] - The terminal selects (or determines) the best beam (S1240)

[0215] - The terminal reports the ID and related quality information (e.g., L1-RSRP) for the selected beam to the base station (S1240). In this case, the reportQuantity of the CSI report config can be set to 'CRI + L1-RSRP'.

[0216] That is, the terminal reports the CRI and the L1-RSRP for the CSI-RS to the base station when the CSI-RS is transmitted for the BM.

[0217] Figure 13 shows an example of resource allocation in the time and frequency domains related to the operation of Figure 10.

[0218] That is, when repetition 'ON' is set in the CSI-RS resource set, multiple CSI-RS resources are repeatedly used by applying the same transmission beam, and when repetition 'OFF' is set in the CSI-RS resource set, different CSI-RS resources can be seen to be transmitted with different transmission beams.

[0219] <dl bm 관련 빔 지시 (beam indication)>

[0220] A terminal may receive an RRC configuration list of at most M candidate Transmission Configuration Indication (TCI) states for the purpose of at least a Quasi Co-location (QCL) indication, where M may be 64.

[0221] Each TCI state can be configured with one RS set. At least each ID of a DL RS for spatial QCL purposes (QCL Type D) within an RS set can refer to one of the DL RS types, such as SSB, P-CSI RS, SP-CSI RS, or A-CSI RS.

[0222] At least the initialization / update of the IDs of DL RS(s) within the RS set used for spatial QCL purposes can be performed at least through explicit signaling.

[0223] [Table 2] shows an example of a TCI-State IE. A TCI-State IE associates one or two DL reference signals (RS) with a corresponding quasi co-location (QCL) type.

[0224]

[0225] In Table 2, the bwp-Id parameter indicates the DL BWP where the RS is located, the cell parameter indicates the carrier where the RS is located, and the referencesignal parameter indicates the reference antenna port(s) that is the source of quasi co-location for the corresponding target antenna port(s) or a reference signal including the same. The target antenna port(s) may be a CSI-RS, a PDCCH DMRS, or a PDSCH DMRS. For example, in order to indicate QCL reference RS information for NZP CSI-RS, the corresponding TCI state ID may be indicated in the NZP CSI-RS resource configuration information. In another example, in order to indicate QCL reference information for PDCCH DMRS antenna port(s), the TCI state ID may be indicated in each CORESET configuration. In another example, in order to indicate QCL reference information for PDSCH DMRS antenna port(s), the TCI state ID may be indicated through DCI.

[0226]

[0227] <QCL(Quasi-Co Location)>

[0228] Antenna ports are defined such that the channel through which a symbol on an antenna port is carried can be inferred from the channel through which another symbol on the same antenna port is carried. Two antenna ports are said to be in a QC / QCL (quasi co-located or quasi co-location) relationship if the properties of the channel through which a symbol on one antenna port is carried can be inferred from the channel through which a symbol on another antenna port is carried.

[0229] Here, the channel characteristics include one or more of delay spread, Doppler spread, frequency / Doppler shift, average received power, received timing / average delay, and spatial RX parameter. Here, the spatial Rx parameter refers to a spatial (reception) channel characteristic parameter such as angle of arrival.

[0230] The UE may be configured with a list of up to M TCI-State configurations in the higher layer parameter PDSCH-Config to decode the PDSCH according to the detected PDCCH having the intended DCI for the UE and the given serving cell. The M depends on the UE capability.

[0231] Each TCI-State contains parameters for establishing a quasi co-location relationship between one or two DL reference signals and the DM-RS port of the PDSCH.

[0232] The quasi-colocation relationship is set by the higher layer parameters qcl-Type1 for the first DL RS and qcl-Type2 (if set) for the second DL RS. For two DL RSs, the QCL types are not the same, regardless of whether the references are the same DL RS or different DL RSs.

[0233] The quasi co-location type corresponding to each DL RS is given by the higher layer parameter qcl-Type of QCL-Info, which can take one of the following values:

[0234] - 'QCL-TypeA': {Doppler shift, Doppler spread, average delay, delay spread}

[0235] - 'QCL-TypeB': {Doppler shift, Doppler spread}

[0236] - 'QCL-TypeC': {Doppler shift, average delay}

[0237] - 'QCL-TypeD': {Spatial Rx parameter}

[0238] For example, if the target antenna port is a specific NZP CSI-RS, the corresponding NZP CSI-RS antenna ports can be instructed / configured to be QCL with a specific TRS from a QCL-Type A perspective and with a specific SSB from a QCL-Type D perspective. A terminal that has received such an instruction / configuration can receive the corresponding NZP CSI-RS using the Doppler and delay values ​​measured at the QCL-TypeA TRS, and apply the reception beam used for QCL-TypeD SSB reception to the corresponding NZP CSI-RS reception.

[0239] The UE can receive an activation command by MAC CE signaling, which is used to map up to eight TCI states to codepoints in the DCI field 'Transmission Configuration Indication'.

[0240]

[0241]

[0242] Depending on the terminal implementation, UL BM may or may not have beam reciprocity (or beam correspondence) between the Tx beam and the Rx beam. If reciprocity between the Tx beam and the Rx beam is established at both the base station and the terminal, the UL beam pair can be aligned through the DL beam pair. However, if reciprocity between the Tx beam and the Rx beam is not established at either the base station or the terminal, a UL beam pair determination process is required separately from the DL beam pair determination.

[0243] Additionally, even if both the base station and the terminal maintain beam correspondence, the base station can use the UL BM procedure for DL ​​Tx beam determination without the terminal requesting reporting of a preferred beam.

[0244] UL BM can be performed via beamformed UL SRS transmission, and whether UL BM is applied to an SRS resource set is determined by the (higher layer parameter) usage. When usage is set to 'BeamManagement (BM)', only one SRS resource can be transmitted for each of multiple SRS resource sets at a given time instant.

[0245] A UE can be configured with one or more Sounding Reference Symbol (SRS) resource sets (via higher layer signaling, RRC signaling, etc.) configured by (higher layer parameter) SRS-ResourceSet. For each SRS resource set, the UE can be configured with K≥1 SRS resources (higher later parameter SRS-resource). Here, K is a natural number, and the maximum value of K is indicated by SRS_capability.

[0246] Similar to DL BM, UL BM procedure can be divided into Tx beam sweeping of the terminal and Rx beam sweeping of the base station.

[0247] Figure 14 shows an example of a UL BM procedure using SRS. Figure 14 (a) shows a base station's Rx beam determination procedure, and Figure 14 (b) shows a terminal's Tx beam sweeping procedure.

[0248] Figure 15 is a flowchart showing an example of a UL BM procedure using SRS.

[0249] - The terminal receives RRC signaling (e.g., SRS-Config IE) from the base station including a usage parameter (higher layer parameter) set to 'beam management' (S1510).

[0250] Table 3 shows an example of an SRS-Config IE (Information Element), which is used to configure SRS transmission. The SRS-Config IE includes a list of SRS-Resources and a list of SRS-ResourceSets. Each SRS resource set represents a set of SRS-resources.

[0251] The network can trigger the transmission of an SRS resource set using the configured aperiodicSRS-ResourceTrigger (L1 DCI).

[0252]

[0253] In Table 3, usage represents a higher layer parameter indicating whether an SRS resource set is used for beam management, or for codebook-based or non-codebook-based transmission. The usage parameter corresponds to the L1 parameter 'SRS-SetUse'. 'spatialRelationInfo' is a parameter indicating the setting of a spatial relation between a reference RS and a target SRS. Here, the reference RS can be an SSB, CSI-RS, or SRS corresponding to the L1 parameter 'SRS-SpatialRelationInfo'. The usage is set for each SRS resource set. - The terminal determines a Tx beam for an SRS resource to be transmitted based on the SRS-SpatialRelation Info included in the SRS-Config IE (S1520). Here, the SRS-SpatialRelation Info is set for each SRS resource, and indicates whether to apply the same beam as the beam used in SSB, CSI-RS, or SRS for each SRS resource. Additionally, SRS-SpatialRelationInfo may or may not be set for each SRS resource.

[0254] - If SRS-SpatialRelationInfo is set in the SRS resource, the same beam used in SSB, CSI-RS, or SRS is applied for transmission. However, if SRS-SpatialRelationInfo is not set in the SRS resource, the terminal randomly determines a Tx beam and transmits SRS through the determined Tx beam (S1530).

[0255] More specifically, for P-SRS with 'SRS-ResourceConfigType' set to 'periodic':

[0256] i) If SRS-SpatialRelationInfo is set to 'SSB / PBCH', the UE transmits the corresponding SRS resource by applying the same spatial domain transmission filter (or generated from the same filter) as the spatial domain Rx filter used for receiving the SSB / PBCH; or

[0257] ii) If SRS-SpatialRelationInfo is set to 'CSI-RS', the UE transmits SRS resources by applying the same spatial domain transmission filter used for receiving periodic CSI-RS or SP CSI-RS; or

[0258] iii) If SRS-SpatialRelationInfo is set to 'SRS', the UE transmits the corresponding SRS resource by applying the same spatial domain transmission filter used for transmitting periodic SRS.

[0259] Beam decision and transmission behavior similar to the above can be applied even when 'SRS-ResourceConfigType' is set to 'SP-SRS' or 'AP-SRS'.

[0260] - Additionally, the terminal may or may not receive feedback on SRS from the base station in the following three cases (S1540).

[0261] i) If Spatial_Relation_Info is set for all SRS resources within the SRS resource set, the terminal transmits SRS using the beam indicated by the base station. For example, if Spatial_Relation_Info indicates the same SSB, CRI, or SRI, the terminal repeatedly transmits SRS using the same beam. This case corresponds to G(a) for the purpose of the base station selecting the Rx beam.

[0262] ii) Spatial_Relation_Info may not be set for all SRS resources within the SRS resource set. In this case, the terminal can freely change the SRS beam while transmitting. That is, this case corresponds to Fig. G(b), where the terminal sweeps the Tx beam.

[0263] iii) Spatial_Relation_Info may be set only for some SRS resources within an SRS resource set. In this case, SRS is transmitted using the indicated beam for the set SRS resources, and for SRS resources for which Spatial_Relation_Info is not set, the terminal may arbitrarily apply a Tx beam for transmission.

[0264]

[0265] E-2. CSI-related actions

[0266] In NR (New Radio) systems, CSI-RS (channel state information-reference signal) is used for time / frequency tracking, CSI computation, L1 (layer 1)-RSRP (reference signal received power) computation, and mobility. Here, CSI computation is related to CSI acquisition, and L1-RSRP computation is related to beam management (BM).

[0267] CSI (channel state information) is a general term for information that can indicate the quality of the wireless channel (or link) formed between the terminal and the antenna port.

[0268] Figure 16 is a flowchart showing an example of a CSI-related procedure.

[0269] - In order to perform one of the purposes of the CSI-RS as described above, a terminal (e.g., user equipment, UE) receives configuration information related to CSI from a base station (e.g., general Node B, gNB) through RRC (radio resource control) signaling (S2610).

[0270] The configuration information related to the above CSI may include at least one of CSI-IM (interference management) resource related information, CSI measurement configuration related information, CSI resource configuration related information, CSI-RS resource related information, or CSI report configuration related information.

[0271] i) CSI-IM resource-related information may include CSI-IM resource information, CSI-IM resource set information, etc. A CSI-IM resource set is identified by a CSI-IM resource set ID (identifier), and one resource set includes at least one CSI-IM resource. Each CSI-IM resource is identified by a CSI-IM resource ID.

[0272] ii) CSI resource configuration related information can be expressed as CSI-ResourceConfig IE. The CSI resource configuration related information defines a group including at least one of a non-zero power (NZP) CSI-RS resource set, a CSI-IM resource set, or a CSI-SSB resource set. That is, the CSI resource configuration related information includes a CSI-RS resource set list, and the CSI-RS resource set list can include at least one of an NZP CSI-RS resource set list, a CSI-IM resource set list, or a CSI-SSB resource set list. A CSI-RS resource set is identified by a CSI-RS resource set ID, and one resource set includes at least one CSI-RS resource. Each CSI-RS resource is identified by a CSI-RS resource ID.

[0273] As shown in [Table 4], parameters indicating the purpose of CSI-RS (e.g., BM-related 'repetition' parameter, tracking-related 'trs-Info' parameter) can be set for each NZP CSI-RS resource set. [Table 4] shows an example of an NZP CSI-RS resource set IE.

[0274] -- ASN1START-- TAG-NZP-CSI-RS-RESOURCESET-STARTNZP-CSI-RS-ResourceSet ::= SEQUENCE {nzp-CSI-ResourceSetId NZP-CSI-RS-ResourceSetId,nzp-CSI-RS-Resources SEQUENCE (SIZE (1..maxNrofNZP-CSI-RS-ResourcesPerSet)) OF NZP-CSI-RS-ResourceId,repetition ENUMERATED { on, off} OPTIONAL,aperiodicTriggeringOffset INTEGER(0..4) OPTIONAL, -- Need Strs-Info ENUMERATED {true} OPTIONAL, -- Need R...}-- TAG-NZP-CSI-RS-RESOURCESET-STOP-- ASN1STOP

[0275] And, the repetition parameter corresponding to the higher layer parameter corresponds to the 'CSI-RS-ResourceRep' of the L1 parameter. iii) Information related to the CSI report configuration includes a report configuration type (reportConfigType) parameter indicating time domain behavior and a report quantity (reportQuantity) parameter indicating the CSI-related quantity to be reported. The time domain behavior may be periodic, aperiodic, or semi-persistent. Information related to the CSI report configuration can be expressed as a CSI-ReportConfig IE, and [Table 5] below shows an example of the CSI-ReportConfig IE. Additionally, [Table 5] below shows examples of CodebookConfigIE and CSI-ResourceConfigIE. CodebookConfigIE is used for Type-I / Type-II codebook configuration (see TS 38.214, clause 5.2.2.2), and CSI-ResourceConfigIE defines one or more groups among {NZP-CSI-RS-ResourceSet, CSI-IM-ResourceSet and / or CSI-SSB-ResourceSet}.

[0276] -- ASN1START-- TAG-CSI-RESOURCECONFIG-STARTCSI-ReportConfiginformation element-- ASN1START-- TAG-CSI-REPORTCONFIG-STARTCSI-ReportConfig ::= SEQUENCE {reportConfigId CSI-ReportConfigId,carrier ServCellIndex OPTIONAL, -- Need SresourcesForChannelMeasurement CSI-ResourceConfigId,csi-IM-ResourcesForInterference CSI-ResourceConfigId OPTIONAL, -- Need Rnzp-CSI-RS-ResourcesForInterference CSI-ResourceConfigId OPTIONAL, -- Need RreportConfigType CHOICE {periodic SEQUENCE {reportSlotConfig CSI-ReportPeriodicityAndOffset,pucch-CSI-ResourceList SEQUENCE (SIZE (1..maxNrofBWPs)) OF PUCCH-CSI-Resource},semiPersistentOnPUCCH SEQUENCE {reportSlotConfig CSI-ReportPeriodicityAndOffset,pucch-CSI-ResourceList SEQUENCE (SIZE (1..maxNrofBWPs)) OF PUCCH-CSI-Resource},semiPersistentOnPUSCH SEQUENCE {reportSlotConfig ENUMERATED {sl5, sl10, sl20, sl40, sl80, sl160, sl320},reportSlotOffsetList SEQUENCE (SIZE (1.. maxNrofUL-Allocations)) OF INTEGER(0..32),p0alpha P0-PUSCH-AlphaSetId},aperiodic SEQUENCE {reportSlotOffsetList SEQUENCE (SIZE (1..maxNrofUL-Allocations)) OF INTEGER(0..32)}},reportQuantity CHOICE {none NULL,cri-RI-PMI-CQI NULL,cri-RI-i1 NULL,cri-RI-i1-CQI SEQUENCE {pdsch-BundleSizeForCSI ENUMERATED {n2, n4} OPTIONAL -- Need S},cri-RI-CQI NULL,cri-RSRP NULL,ssb-Index-RSRP NULL,cri-RI-LI-PMI-CQI NULL},reportFreqConfiguration SEQUENCE {cqi-FormatIndicator ENUMERATED { widebandCQI, subbandCQI} OPTIONAL, -- Need Rpmi-FormatIndicator ENUMERATED { widebandPMI, subbandPMI} OPTIONAL, -- Need Rcsi-ReportingBand CHOICE {subbands3 BIT STRING(SIZE(3)),subbands4 BIT STRING(SIZE(4)),subbands5 BIT STRING(SIZE(5)),subbands6 BIT STRING(SIZE(6)),subbands7 BIT STRING(SIZE(7)),subbands8 BIT STRING(SIZE(8)),subbands9 BIT STRING(SIZE(9)),subbands10 BIT STRING(SIZE(10)),subbands11 BIT STRING(SIZE(11)),subbands12 BIT STRING(SIZE(12)),subbands13 BIT STRING(SIZE(13)),subbands14 BIT STRING(SIZE(14)),subbands15 BIT STRING(SIZE(15)),subbands16 BIT STRING(SIZE(16)),subbands17 BIT STRING(SIZE(17)),subbands18 BIT STRING(SIZE(18)),...,subbands19-v1530 BIT STRING(SIZE(19))} OPTIONAL -- Need S} OPTIONAL, -- Need RtimeRestrictionForChannelMeasurements ENUMERATED {configured, notConfigured},timeRestrictionForInterferenceMeasurements ENUMERATED {configured, notConfigured},codebookConfig CodebookConfig OPTIONAL, -- Need Rdummy ENUMERATED {n1, n2} OPTIONAL, -- Need RgroupBasedBeamReporting CHOICE {enabled NULL,disabled SEQUENCE {nrofReportedRS ENUMERATED {n1, n2, n3, n4} OPTIONAL -- Need S}},cqi-Table ENUMERATED {table1, table2, table3, spare1} OPTIONAL, -- Need RsubbandSize ENUMERATED {value1, value2},non-PMI-PortIndication SEQUENCE (SIZE (1..maxNrofNZP-CSI-RS-ResourcesPerConfig)) OF PortIndexFor8Ranks OPTIONAL, -- Need R...,[[semiPersistentOnPUSCH-v1530 SEQUENCE {reportSlotConfig-v1530 ENUMERATED {sl4, sl8, sl16}} OPTIONAL -- Need R]],[[semiPersistentOnPUSCH-v1610 SEQUENCE {reportSlotOffsetListDCI-0-2-r16 SEQUENCE (SIZE (1.. maxNrofUL-Allocations-r16)) OF INTEGER(0..32) OPTIONAL, -- Need RreportSlotOffsetListDCI-0-1-r16 SEQUENCE (SIZE (1.. maxNrofUL-Allocations-r16)) OF INTEGER(0..32) OPTIONAL -- Need R} OPTIONAL, -- Need Raperiodic-v1610 SEQUENCE {reportSlotOffsetListDCI-0-2-r16 SEQUENCE (SIZE (1.. maxNrofUL-Allocations-r16)) OF INTEGER(0..32) OPTIONAL, -- Need RreportSlotOffsetListDCI-0-1-r16 SEQUENCE (SIZE (1.. maxNrofUL-Allocations-r16)) OF INTEGER(0..32) OPTIONAL -- Need R} OPTIONAL, -- Need RreportQuantity-r16 CHOICE {cri-SINR-r16 NULL,ssb-Index-SINR-r16 NULL} OPTIONAL, -- Need RcodebookConfig-r16 CodebookConfig-r16 OPTIONAL -- Need R]]}-CodebookConfigThe IECodebookConfigis used to configure codebooks of Type-I and Type-II (see TS 38.214

[0019] ,clause 5.2.2.2)CodebookConfiginformation element-- ASN1START-- TAG-CODEBOOKCONFIG-STARTCodebookConfig ::= SEQUENCE {codebookType CHOICE {type1 SEQUENCE {subType CHOICE {typeI-SinglePanel SEQUENCE {nrOfAntennaPorts CHOICE {two SEQUENCE {twoTX-CodebookSubsetRestriction BIT STRING (SIZE (6))},moreThanTwo SEQUENCE {n1-n2 CHOICE {two-one-TypeI-SinglePanel-Restriction BIT STRING (SIZE (8)),two-two-TypeI-SinglePanel-Restriction BIT STRING (SIZE (64)),four-one-TypeI-SinglePanel-Restriction BIT STRING (SIZE (16)),three-two-TypeI-SinglePanel-Restriction BIT STRING (SIZE (96)),six-one-TypeI-SinglePanel-Restriction BIT STRING (SIZE (24)),four-two-TypeI-SinglePanel-Restriction BIT STRING (SIZE (128)),eight-one-TypeI-SinglePanel-Restriction BIT STRING (SIZE (32)),four-three-TypeI-SinglePanel-Restriction BIT STRING (SIZE (192)),six-two-TypeI-SinglePanel-Restriction BIT STRING (SIZE (192)),twelve-one-TypeI-SinglePanel-Restriction BIT STRING (SIZE (48)),four-four-TypeI-SinglePanel-Restriction BIT STRING (SIZE (256)),eight-two-TypeI-SinglePanel-Restriction BIT STRING (SIZE (256)),sixteen-one-TypeI-SinglePanel-Restriction BIT STRING (SIZE (64))},typeI-SinglePanel-codebookSubsetRestriction-i2 BIT STRING (SIZE (16)) OPTIONAL -- Need R}},typeI-SinglePanel-ri-Restriction BIT STRING (SIZE (8))},typeI-MultiPanel SEQUENCE {ng-n1-n2 CHOICE {two-two-one-TypeI-MultiPanel-Restriction BIT STRING (SIZE (8)),two-four-one-TypeI-MultiPanel-Restriction BIT STRING (SIZE (16)),four-two-one-TypeI-MultiPanel-Restriction BIT STRING (SIZE (8)),two-two-two-TypeI-MultiPanel-Restriction BIT STRING (SIZE (64)),two-eight-one-TypeI-MultiPanel-Restriction BIT STRING (SIZE (32)),four-four-one-TypeI-MultiPanel-Restriction BIT STRING (SIZE (16)),two-four-two-TypeI-MultiPanel-Restriction BIT STRING (SIZE (128)),four-two-two-TypeI-MultiPanel-Restriction BIT STRING (SIZE (64))},ri-Restriction BIT STRING (SIZE (4))}},codebookMode INTEGER (1..2)},type2 SEQUENCE {subType CHOICE {typeII SEQUENCE {n1-n2-codebookSubsetRestriction CHOICE {two-one BIT STRING (SIZE (16)),two-two BIT STRING (SIZE (43)),four-one BIT STRING (SIZE (32)),three-two BIT STRING (SIZE (59)),six-one BIT STRING (SIZE (48)),four-two BIT STRING (SIZE (75)),eight-one BIT STRING (SIZE (64)),four-three BIT STRING (SIZE (107)),six-two BIT STRING (SIZE (107)),twelve-one BIT STRING (SIZE (96)),four-four BIT STRING (SIZE (139)),eight-two BIT STRING (SIZE (139)),sixteen-one BIT STRING (SIZE (128))},typeII-RI-Restriction BIT STRING (SIZE (2))},typeII-PortSelection SEQUENCE {portSelectionSamplingSize ENUMERATED {n1, n2, n3, n4} OPTIONAL, -- Need RtypeII-PortSelectionRI-Restriction BIT STRING (SIZE (2))}},phaseAlphabetSize ENUMERATED {n4, n8},subbandAmplitude BOOLEAN,numberOfBeams ENUMERATED {two, three,four}}}}CodebookConfig-r16 ::= SEQUENCE {codebookType CHOICE {type2 SEQUENCE {subType CHOICE {typeII-r16 SEQUENCE {n1-n2-codebookSubsetRestriction-r16 CHOICE {two-one BIT STRING (SIZE (16)),two-two BIT STRING (SIZE (43)),four-one BIT STRING (SIZE (32)),three-two BIT STRING (SIZE (59)),six-one BIT STRING (SIZE (48)),four-two BIT STRING (SIZE (75)),eight-one BIT STRING (SIZE (64)),four-three BIT STRING (SIZE (107)),six-two BIT STRING (SIZE (107)),twelve-one BIT STRING (SIZE (96)),four-four BIT STRING (SIZE (139)),eight-two BIT STRING (SIZE (139)),sixteen-one BIT STRING (SIZE (128))},typeII-RI-Restriction-r16 BIT STRING (SIZE(4))},typeII-PortSelection-r16 SEQUENCE {portSelectionSamplingSize-r16 ENUMERATED {n1, n2, n3, n4},typeII-PortSelectionRI-Restriction-r16 BIT STRING (SIZE (4))}},numberOfPMI-SubbandsPerCQI-Subband-r16 INTEGER (1..2),paramCombination-r16 INTEGER (1..8)}}}-- TAG-CODEBOOKCONFIG-STOP-- ASN1STOP-CSI-ResourceConfigThe IECSI-ResourceConfigdefines a group of one or moreNZP-CSI-RS-ResourceSet,CSI-IM-ResourceSetand / orCSI-SSB-ResourceSet.CSI-ResourceConfiginformation element-- ASN1START-- TAG-CSI-RESOURCECONFIG-STARTCSI-ResourceConfig ::= SEQUENCE {csi-ResourceConfigId CSI-ResourceConfigId,csi-RS-ResourceSetList CHOICE {nzp-CSI-RS-SSB SEQUENCE {nzp-CSI-RS-ResourceSetList SEQUENCE (SIZE (1..maxNrofNZP-CSI-RS-ResourceSetsPerConfig)) OF NZP-CSI-RS-ResourceSetIdOPTIONAL, -- Need Rcsi-SSB-ResourceSetList SEQUENCE (SIZE (1..maxNrofCSI-SSB-ResourceSetsPerConfig)) OF CSI-SSB-ResourceSetId OPTIONAL -- Need R},csi-IM-ResourceSetList SEQUENCE (SIZE (1..maxNrofCSI-IM-ResourceSetsPerConfig)) OF CSI-IM-ResourceSetId},bwp-Id BWP-Id,resourceType ENUMERATED { aperiodic, semiPersistent, periodic},...},

[0277] - The terminal measures CSI based on configuration information related to the CSI (S2620). The CSI measurement may include (1) a process of receiving a CSI-RS by the terminal (S2621) and (2) a process of computing CSI using the received CSI-RS (S2622), which will be described in detail later. The CSI-RS sets the RE (resource element) mapping of the CSI-RS resource in the time and frequency domains by the higher layer parameter CSI-RS-ResourceMapping.

[0278] [Table 6] shows an example of the CSI-RS-ResourceMapping IE.

[0279] -- ASN1START-- TAG-CSI-RS-RESOURCEMAPPING-STARTCSI-RS-ResourceMapping ::= SEQUENCE {frequencyDomainAllocation CHOICE {row1 BIT STRING (SIZE (4)),row2 BIT STRING (SIZE (12)),row4 BIT STRING (SIZE (3)),other BIT STRING (SIZE (6))},nrofPorts ENUMERATED {p1,p2,p4,p8,p12,p16,p24,p32},firstOFDMSymbolInTimeDomain INTEGER (0..13),firstOFDMSymbolInTimeDomain2 INTEGER (2..12) OPTIONAL, -- Need Rcdm-Type ENUMERATED {noCDM, fd-CDM2, cdm4-FD2-TD2, cdm8-FD2-TD4},density CHOICE {dot5 ENUMERATED {evenPRBs, oddPRBs},one NULL,three NULL,spare NULL},freqBand CSI-FrequencyOccupation,...}

[0280] In [Table 6], density (D) represents the density of CSI-RS resources measured in RE / port / PRB (physical resource block), and nrofPorts represents the number of antenna ports. - The terminal reports the measured CSI to the base station (S2630). Here, if the quantity of CSI-ReportConfig in Table E is set to 'none (or No report)', the terminal may omit the report.

[0281] However, even if the above quantity is set to 'none (or No report)', the terminal may report to the base station.

[0282] When the above quantity is set to 'none', it triggers an aperiodic TRS or repetition is set.

[0283] Here, the report of the terminal can be omitted only when repetition is set to 'ON'.

[0284]

[0285] CSI measurement

[0286] The NR system supports more flexible and dynamic CSI measurement and reporting. Here, the CSI measurement may include a procedure for receiving a CSI-RS and computing the received CSI-RS to acquire CSI.

[0287] As a time-domain behavior for CSI measurement and reporting, aperiodic / semi-persistent / periodic channel measurement (CM) and interference measurement (IM) are supported. A 4-port NZP CSI-RS RE pattern is used to configure CSI-IM.

[0288] NR's CSI-IM-based IMR has a similar design to LTE's CSI-IM and is configured independently of the ZP CSI-RS resources for PDSCH rate matching. Furthermore, in the NZP CSI-RS-based IMR, each port emulates an interference layer with (preferred channel and) precoded NZP CSI-RS. This is for intra-cell interference measurement in multi-user cases, primarily targeting MU interference.

[0289] The base station transmits precoded NZP CSI-RS to the terminal on each port of the configured NZP CSI-RS-based IMR.

[0290] The terminal assumes a channel / interference layer for each port in the resource set and measures interference.

[0291] For a channel, if there is no PMI and RI feedback, multiple resources are configured in a set, and the base station or network indicates a subset of NZP CSI-RS resources via DCI for channel / interference measurement.

[0292] Let's take a closer look at resource settings and resource setting configuration.

[0293]

[0294] Resource setting

[0295] Each CSI resource setting 'CSI-ResourceConfig' contains a configuration for S≥1 CSI resource sets (given by the higher layer parameter csi-RS-ResourceSetList). A CSI resource setting corresponds to a CSI-RS-resourcesetlist, where S represents the number of configured CSI-RS resource sets. Here, the configuration for S≥1 CSI resource sets contains each CSI resource set containing CSI-RS resources (consisting of NZP CSI-RS or CSI-IM) and SS / PBCH block (SSB) resources used for L1-RSRP computation.

[0296] Each CSI resource setting is located in a DL bandwidth part (BWP) identified by the higher layer parameter bwp-id. All CSI resource settings linked to a CSI reporting setting have the same DL BWP.

[0297] The time domain behavior of CSI-RS resources within a CSI resource setting included in the CSI-ResourceConfig IE is indicated by the higher layer parameter resourceType, and can be set to aperiodic, periodic, or semi-persistent. For periodic and semi-persistent CSI resource settings, the number of configured CSI-RS resource sets (S) is limited to '1'. For periodic and semi-persistent CSI resource settings, the configured periodicity and slot offset are given in the numerology of the associated DL BWP, as given by bwp-id.

[0298] When a UE is configured with multiple CSI-ResourceConfigs containing the same NZP CSI-RS resource ID, the same time domain behavior is configured for the CSI-ResourceConfigs.

[0299] When a UE is configured with multiple CSI-ResourceConfigs containing the same CSI-IM resource ID, the same time domain behavior is configured for the CSI-ResourceConfigs.

[0300] One or more CSI resource settings for channel measurement (CM) and interference measurement (IM) are configured via higher layer signaling.

[0301] - CSI-IM resource for interference measurement.

[0302] - NZP CSI-RS resources for interference measurement.

[0303] - NZP CSI-RS resources for channel measurement.

[0304] That is, the CMR (channel measurement resource) can be NZP CSI-RS for CSI acquisition, and the IMR (Interference measurement resource) can be NZP CSI-RS for CSI-IM and IM.

[0305] Here, CSI-IM (or ZP CSI-RS for IM) is mainly used for inter-cell interference measurement.

[0306] And, NZP CSI-RS for IM is mainly used for intra-cell interference measurement from multi-user.

[0307] The UE may assume that the CSI-RS resource(s) for channel measurement and the CSI-IM / NZP CSI-RS resource(s) for interference measurement configured for one CSI reporting are 'QCL-TypeD' per resource.

[0308]

[0309] Resource setting configuration

[0310] As we have seen, resource setting can mean a resource set list.

[0311] For aperiodic CSI, each trigger state set using the higher layer parameter CSI-AperiodicTriggerState is associated with one or more CSI-ReportConfigs, each of which links to a periodic, semi-persistent, or aperiodic resource setting.

[0312] One reporting setting can be linked to up to three resource settings.

[0313] - When a resource setting is set, the resource setting (given by the higher layer parameter resourcesForChannelMeasurement) is for channel measurement for L1-RSRP computation.

[0314] - When two resource settings are set, the first resource setting (given by the higher layer parameter resourcesForChannelMeasurement) is for channel measurement, and the second resource setting (given by csi-IM-ResourcesForInterference or nzp-CSI-RS -ResourcesForInterference) is for interference measurement performed on CSI-IM or NZP CSI-RS.

[0315] - When three resource settings are set, the first resource setting (given by resourcesForChannelMeasurement) is for channel measurement, the second resource setting (given by csi-IM-ResourcesForInterference) is for CSI-IM based interference measurement, and the third resource setting (given by nzp-CSI-RS-ResourcesForInterference) is for NZP CSI-RS based interference measurement.

[0316] For semi-persistent or periodic CSI, each CSI-ReportConfig is linked to a periodic or semi-persistent resource setting.

[0317] - When one resource setting (given by resourcesForChannelMeasurement) is set, the resource setting is for channel measurement for L1-RSRP computation.

[0318] - When two resource settings are set, the first resource setting (given by resourcesForChannelMeasurement) is for channel measurement, and the second resource setting (given by the higher layer parameter csi-IM-ResourcesForInterference) is used for interference measurement performed on CSI-IM.

[0319]

[0320] CSI computation

[0321] When interference measurements are performed on CSI-IM, each CSI-RS resource for channel measurements is associated with a CSI-IM resource in the order of the CSI-RS resources and CSI-IM resources within the corresponding resource set. The number of CSI-RS resources for channel measurements is equal to the number of CSI-IM resources.

[0322] And, if interference measurement is performed on NZP CSI-RS, the UE does not expect to be configured with more than one NZP CSI-RS resource in the associated resource set within the resource setting for channel measurement.

[0323] A terminal with the higher layer parameter nzp-CSI-RS-ResourcesForInterference set does not expect more than 18 NZP CSI-RS ports to be set within the NZP CSI-RS resource set.

[0324] For CSI measurement, the terminal assumes the following:

[0325] - Each NZP CSI-RS port configured for interference measurement corresponds to an interference transport layer.

[0326] - All interference transmission layers of the NZP CSI-RS port for interference measurement consider the EPRE (energy per resource element) ratio.

[0327] - Other interference signals on RE(s) of NZP CSI-RS resource for channel measurement, NZP CSI-RS resource for interference measurement or CSI-IM resource for interference measurement.

[0328]

[0329] CSI report

[0330] For CSI reporting, the time and frequency resources available to the UE are controlled by the base station.

[0331] CSI (channel state information) 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), or an L1-RSRP.

[0332] For CQI, PMI, CRI, SSBRI, LI, RI, and L1-RSRP, the UE is configured by a higher layer with N≥1 CSI-ReportConfig reporting settings, M≥1 CSI-ResourceConfig resource settings, and a list of one or two trigger states (provided by aperiodicTriggerStateList and semiPersistentOnPUSCH-TriggerStateList). Each trigger state in the aperiodicTriggerStateList includes a list of associated CSI-ReportConfigs indicating channel and optionally resource set IDs for interference. Each trigger state in the semiPersistentOnPUSCH-TriggerStateList includes one associated CSI-ReportConfig.

[0333] Additionally, the time domain behavior of CSI reporting supports periodic, semi-persistent, and aperiodic.

[0334] i) Periodic CSI reporting is performed on short PUCCH and long PUCCH. The periodicity and slot offset of periodic CSI reporting can be configured via RRC, and refer to the CSI-ReportConfig IE.

[0335] ii) SP (semi-periodic) CSI reporting is performed on short PUCCH, long PUCCH, or PUSCH.

[0336] In case of SP CSI on short / long PUCCH, the period and slot offset are set by RRC, and CSI reporting is activated / deactivated by a separate MAC CE.

[0337] 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 on PUSCH, a separate RNTI (SP-CSI C-RNTI) is used.

[0338] The initial CSI reporting timing follows the PUSCH time domain allocation value indicated in the DCI, and subsequent CSI reporting timing follows the cycle set by RRC.

[0339] DCI format 0_1 ​​contains a CSI request field and can activate / deactivate a specific configured SP-CSI trigger state. SP CSI reporting has the same or similar activation / deactivation mechanism as data transmission on the SPS PUSCH.

[0340] iii) Aperiodic CSI reporting is performed on PUSCH and is triggered by DCI. In this case, information related to the triggering of aperiodic CSI reporting can be transmitted / indicated / configured via MAC-CE.

[0341] For AP CSI with AP CSI-RS, AP CSI-RS timing is set by RRC, and timing for AP CSI reporting is dynamically controlled by DCI.

[0342] NR does not apply the method of dividing CSI into multiple reporting instances (e.g., transmitting in the order of RI, WB PMI / CQI, and SB PMI / CQI) used for PUCCH-based CSI reporting in LTE. Instead, NR restricts specific CSI reporting on short / long PUCCHs and defines CSI omission rules. Furthermore, with respect to AP CSI reporting timing, PUSCH symbol / slot locations are dynamically indicated by DCI. Candidate slot offsets are configured by RRC. For CSI reporting, the slot offset (Y) is configured for each reporting setting. For UL-SCH, the slot offset K2 is configured separately.

[0343] Two CSI latency classes (low latency class, high latency class) are defined from the perspective of CSI computation complexity. Low latency CSI is WB CSI including up to 4 ports Type-I codebook or up to 4-port non-PMI feedback CSI. High latency CSI refers to any CSI other than low latency CSI. For a normal terminal, (Z, Z') is defined in units of OFDM symbols. Here, Z represents the minimum CSI processing time from receiving an aperiodic CSI triggering DCI to performing a CSI report. In addition, Z' represents the minimum CSI processing time from receiving a CSI-RS for channel / interference to performing a CSI report.

[0344] Additionally, the terminal reports the number of CSIs it can calculate simultaneously. The following describes the CSI reporting configuration defined in TS 38.214.

[0345] -----------------------------------------------------------------------

[0346] 5.2.1.4 Report Settings

[0347] The UE computes the CSI parameters assuming the following dependencies between the CSI parameters (if reported):

[0348] -LI is calculated conditionally based on reported CQI, PMI, RI and CRI.

[0349] -CQI is calculated conditionally based on reported PMI, RI and CRI.

[0350] -PMI is calculated conditionally based on reported RI and CRI.

[0351] -RI is calculated conditionally based on the reported CRI.

[0352] Reporting configurations for CSI can be aperiodic (using PUSCH), periodic (using PUCCH), or semi-persistent (using PUCCH and DCI-enabled PUSCH). CSI-RS resources can be periodic, semi-persistent, or aperiodic. Table 5.2.1.4-1 lists the supported combinations of CSI reporting configurations and CSI-RS resource configurations, and how CSI reporting is triggered for each CSI-RS resource configuration. Periodic CSI-RS is configured at higher layers. Semi-persistent CSI-RS is enabled and disabled as described in Section 5.2.1.5.2. Aperiodic CSI-RS is configured and triggered / activated as described in Section 5.2.1.5.1.

[0353] Table 5.2.1.4-1: CSI Reporting Trigger / Enable for Possible CSI-RS Configurations

[0354]

[0355] -----------------------------------------------------------------------

[0356] Additionally, the following description is information related to activation / deactivation / trigger by MAC-CE related to Semi-Persistent / Aperiodic CSI reporting defined in TS 38.321.

[0357] -----------------------------------------------------------------------

[0358] 5. 18.2 Enabling / Disabling a Semi-Static CSI-RS / CSI-IM Resource Set

[0359] The network can activate and deactivate the configured semi-persistent CSI-RS / CSI-IM resource set of the serving cell by sending the SP CSI-RS / CSI-IM Resource Set Activation / Deactivation MAC CE described in Section 6.1.3.12. The configured semi-persistent CSI-RS / CSI-IM resource set is initially deactivated during configuration and after a handover.

[0360] MAC entity is

[0361] 1> When the MAC entity receives the SP CSI-RS / CSI-IM resource set activation / deactivation MAC CE from the serving cell.

[0362] 2; Indicates information about MAC CE for enabling / disabling SP CSI-RS / CSI-IM resource set to lower layers.

[0363] 5.18.3 Aperiodic CSI Trigger State Sub-Options

[0364] The network can select among the configured aperiodic CSI trigger states of the serving cell by sending an aperiodic CSI trigger state subselect MAC CE as described in Section 6.1.3.13.

[0365] MAC entity is

[0366] 1> When a MAC entity receives an aperiodic CSI trigger state sub-select MAC CE from the serving cell:

[0367] 2> Indicates information about the aperiodic CSI trigger state sub-selected MAC CE to the lower layer.

[0368] -----------------------------------------------------------------------

[0369]

[0370] Description of the Unified TCI framework

[0371] In Release-17, both the DL TCI state and the UL TCI state can be indicated through DL DCI (e.g. DCI format 1-1 or 1-2), or only the UL TCI state can be indicated without indicating the DL TCI state. Therefore, the methods used for UL beam and power control (PC) configuration in the existing R15 / R16 are replaced in R17 with the above UL TCI state indication method. More specifically, in R17, one UL TCI state can be indicated through the TCI field of the DL DCI, and the UL TCI state is applied to all PUSCHs and all PUCCHs after a certain time called the beam application time, and can be applied to some or all of the indicated SRS resource sets. In R18, a method in which multiple UL TCI states (and / or DL ​​TCI states) are indicated through the TCI field of the DL DCI is under discussion.

[0372]

[0373] Specific embodiments of the present disclosure

[0374] The present disclosure relates to a technology for utilizing SSB (synchronization signal / physical broadcast channel block) in an on-demand manner in a wireless communication system. Specifically, the present disclosure proposes a technology for performing various functions using on-demand SSB in a cell or frequency band where transmission of SSB (e.g., synchronization signal, MIB) and / or system information (e.g., MIB, SIB) has been temporarily suspended for NES operation. Specifically, the present disclosure proposes a technology related to the contents and signaling of configuration information required for operating on-demand SSB in an SSB-less cell. Hereinafter, in the present disclosure, ' / ' means 'and', 'or', or 'and / or' depending on the context.

[0375]

[0376] The base station can operate technologies such as controlling the on / off of the UE for a certain period of time in the time axis for the purpose of NES, controlling the transmission / reception resources for UE-common or UE-specific signals / channels, changing the amount of frequency-axis resources, controlling the transmission power, or turning on / off the antenna port (AP), TRP, etc. in the spatial domain. In the present disclosure, the listed technologies are referred to as 'NES technologies' or 'NES_tech', and the state in which at least one of the NES_techs is applied is referred to as 'NES mode' or 'NES state'. The base station can inform the terminal of which NES_tech(s) is applied for each NES_tech or NES_tech group [Approach 1], or can preset the corresponding NES_tech or NES_tech group(s) for each code-point of a specific indicator [Approach 2]. Here, specific indicators may be indicated by DCI or MAC CE, etc., or may be set by higher layer signaling.

[0377] For Approach 1, if at least one NES_tech is applied to the terminal, the state can be defined as an NES mode or NES state, and further, can be treated as a different NES mode or different NES state depending on which NES_tech is applied. The NES mode or NES state can be used as a concept to indicate whether at least one NES technology is applied, or further to indicate which NES technology(s) are applied. If the NES mode or NES state further indicates which NES technology(s) are applied, different NES modes or different NES states can include different combinations of NES_tech. For Approach 2, for example, if a 1-bit indicator is used, '0' can indicate that the corresponding NES_tech is not applied, and '1' can indicate that at least one NES_tech is applied. In this case, if '1' is indicated through the indicator, the state can be defined as an NES mode or NES state. As another example, when a 2-bit indicator is used, '00' can indicate that there is no corresponding NES_tech, '01' can indicate that at least one NES_tech_A is applied, '10' can indicate that at least one NES_tech_B is applied, and '11' can indicate that at least one NES_tech_C is applied. In this case, if a code-point other than '00' is indicated through the indicator, the state can be defined as an NES mode or NES state. Furthermore, the terminal can determine NES state #1 when '01' is identified, NES state #2 when '10' is identified, and NES state #3 when '11' is identified. Accordingly, whether it is an NES state and / or which NES state it is can be distinguished for each code-point.

[0378] For NES purposes, the base station can turn on / off certain spatial elements (e.g., APs, active transmit / receive chains, panels or TRPs) or adjust the power value for the downlink signal / channel. To dynamically apply various NES techniques in the spatial and power domains, the base station can associate CSI-RS resources or resource sets with different APs for a single CSI report setting (e.g., CSI-ReportConfig) or associate multiple power offsets (e.g., powerControlOffset parameter, which is a power offset value between PDSCH and CSI-RS, powerControlOffsetSS parameter, which is a power offset value between SSS and CSI-RS, etc.).

[0379] Specifically, at least one of the following CSI frameworks may be introduced:

[0380] - Framework #1: Multiple CSI-RS resource sets are linked for one CMR (channel measurement resource) or one IMR (interference measurement resource) in CSI-ReportConfig. Here, the CMR can be set by the resourcesForChannelMeasurement parameter, and the IMR can be set by the csi-IM-ResourcesForInterference or nzp-CSI-RS-ResourcesForInterference parameter. For example, for CMR, CSI-RS resource set #1 and CSI-RS resource set #2 are linked, and the CSI-RS resources belonging to CSI-RS resource set #1 can be configured with 16 APs (antenna ports, APs), and the CSI-RS resources belonging to CSI-RS resource set #2 can be configured with 8 APs.

[0381] - Framework #2: When a CSI-RS resource set linked to a CMR or an IMR in CSI-ReportConfig is configured, at least one CSI-RS resource(s) with different properties such as the number of APs and / or power offsets within the CSI-RS resource set are configured. For example, for a CSI-RS resource set #1 configured as CMR, CSI-RS resource #1 belonging to the CSI-RS resource set #1 may be configured with 16 APs, and CSI-RS resource #2 belonging to the same set may be configured with 8 APs. For example, for a CSI-RS resource set #1 configured as CMR, CSI-RS resource #1 belonging to the CSI-RS resource set #1 may be configured with the power offset #1 value, and CSI-RS resource #2 belonging to the same set may be configured with the power offset #2 value.

[0382] - Framework #3: When a CSI-RS resource set linked to a CMR or an IMR is configured in CSI-ReportConfig, some or all CSI-RS resource(s) within the set can be configured with multiple AP numbers and / or power offset values. For example, for a CSI-RS resource set #1 configured with a CMR, CSI-RS resource #1 belonging to the CSI-RS resource set #1 can be configured with up to 16 APs, and CSI reporting utilizing at least one AP among them can be configured. Alternatively, CSI-RS resource #2 belonging to the same CSI-RS resource set #1 can be configured with multiple power offset values, and CSI reporting utilizing all or part of the power offsets can be configured.

[0383] For the CSI frameworks described above, the CSI reporting method can be defined through at least one of the following options.

[0384] - Option #1: CSIs that consider multiple AP count values ​​and / or multiple power offset values ​​set in a single CSI report may all be included in a single CSI report. Alternatively, CSIs that consider multiple AP count values ​​and / or multiple power offset values ​​determined through the configuration / instruction of the base station may be included in a single CSI report. In this case, the AP count values ​​and / or power offset values ​​set / instructed through the base station may be some of the AP count values ​​and / or power offset values ​​set in the corresponding CSI report.

[0385] - Option #2: Even if multiple AP count values ​​and / or multiple power offset values ​​are set in one CSI report, CSI(s) considering a single AP count value and / or a single power offset value can be included in one CSI report through the base station's configuration / instruction.

[0386] - Option #3: Even if multiple AP count values ​​and / or multiple power offset values ​​are set in one CSI report, CSI(s) that consider some AP count values ​​and / or some power offset values ​​may be included in one CSI report through judgment / decision / selection of the terminal based on criteria set in advance by the base station or defined in advance.

[0387] Within a configuration for CSI reporting (e.g., CSI-ReportConfig), one or more L sub-configurations can be configured, and each sub-configuration can correspond to either a spatial domain adaptation pattern or a power domain adaptation pattern.

[0388] Here, the spatial domain adaptation pattern may correspond to a specific number of APs or an AP on / off pattern, or may correspond to a specific CSI-RS power value (e.g., the CSI-RS power value determined by the powerControlOffsetSS parameter, which is a power offset value between SSS and CSI-RS, because the turning off of some antenna elements corresponding to one AP may affect the CSI-RS power value). For example, when applying framework #2, the number of APs A1 or the power value P1 may be set for the CSI-RS index #n1 belonging to the resource set, and the number of APs A2 or the power value P2 may be set for the CSI-RS index #n2 belonging to the same resource set. In this case, the sub-configuration index #s1 is set to be linked with the CSI-RS index #n1, and the sub-configuration index #s2 is set to be linked with the CSI-RS index #n2, so that the spatial domain adaptation pattern can be set differently for each sub-configuration. When applying the Framework #3 method, when the number of A1 APs (or P1 / P2 power values) is set for the CSI-RS index #n1 belonging to the resource set, the number of A1 APs (or P1 power values ​​or delta values ​​from the P1 power values) is linked to the sub-configuration index #s1, and the number of A2 APs (or P2 power values ​​or delta values ​​from the P1 power values) that is less than the number of A1 APs that constitute the CSI-RS index #n1 is linked to the sub-configuration index #s2, so that the spatial domain adaptation pattern can be set differently for each sub-configuration.

[0389] In addition, the power domain adaptation pattern may mean that the power offset value (e.g., the power offset value determined by the powerControlOffset parameter, which is the power offset value between PDSCH and CSI-RS, the powerControlOffsetSS parameter, which is the power offset value between SSS and CSI-RS, etc.) is changed. For example, when applying framework #2, the P1 power value may be set for the CSI-RS index #n1 belonging to the resource set, and the P2 power value may be set for the CSI-RS index #n2 belonging to the same resource set. In this case, the sub-configuration index #s1 may be linked to the CSI-RS index #n1, and the sub-configuration index #s2 may be linked to the CSI-RS index #n2, so that the power domain adaptation pattern may be set differently for each sub-configuration.

[0390] In addition, when applying framework #3, the P1 power value and the P2 power value can be set for the CSI-RS index #n1 belonging to the resource set. In this case, the sub-configuration index #s1 is set to be linked to the P1 power value, and the sub-configuration index #s2 is set to be linked to the P2 power value or the delta value from the P1 power value, so that the power domain adaptation pattern can be set differently for each sub-configuration.

[0391] By utilizing one of the aforementioned options #1 / 2 / 3, the terminal may feed back to the base station a CSI report including CSI(s) corresponding to N sub-configurations, which are 1 to L, among L sub-configurations.

[0392]

[0393] According to the TS 38.214 standard document, at least one sub-configuration can be configured within a CSI reporting configuration, and within each sub-configuration, one or a combination of the following configurations can be configured:

[0394] - A list of IDs of one or more CSI-RS resource(s).

[0395] - Antenna port subset indication consisting of a bitmap

[0396] - Additional power offset delta from the EPRE offset between PDSCH and CSI-RS set within the CSI-RS resource configuration.

[0397] In the present disclosure, for convenience of description, a CSI reporting configuration including a sub-configuration in which an ID list of at least one CSI-RS resource(s) is set is referred to as Type 2 spatial domain (SD) adaptation, a CSI reporting configuration including a sub-configuration in which an antenna port subset indication configured as a bitmap is set is referred to as Type 1 spatial domain adaptation, and a CSI reporting configuration including a sub-configuration in which an additional power offset delta value is set is referred to as Power Domain (PD) adaptation. An ID list of at least one CSI-RS resource(s) and / or a power offset delta value may be set for sub-configuration(s) belonging to one CSI reporting configuration, which is referred to as Type 2 spatial domain+power domain adaptation. Additionally, an antenna port subset indication and / or a power offset delta value configured as a bitmap may be set for sub-configuration(s) belonging to one CSI reporting configuration, which is referred to as Type 1 spatial domain+power domain adaptation. For Type 1 spatial domain or power domain or Type 1 spatial domain+power domain adaptation, each CSI-RS resource can be associated with each of all sub-configurations configured within one CSI reporting configuration. For Type 2 spatial domain adaptation, each CSI-RS resource can be associated with only a single sub-configuration among multiple sub-configurations within one CSI reporting configuration. For Type 2 spatial domain+power domain adaptation, the list #1 of CSI-RS resource(s) configured in a sub-configuration within the same CSI reporting configuration and the list #2 of CSI-RS resource(s) configured in another sub-configuration may be the same or disjoint.

[0398] Meanwhile, if L sub-configurations are configured within a CSI reporting configuration, the UE can report CSIs corresponding to each of the L sub-configurations to the base station via a PUSCH / PUCCH. Among the L sub-configurations, only N (L or more and 1 or more) sub-configurations(es) can be activated or triggered via MAC-CE or DCI, in which case the UE can report CSIs corresponding to each of the N sub-configurations to the base station via a PUSCH / PUCCH. Specifically, for a CSI reporting configuration in which semi-persistent CSI reporting on PUCCH (SP CSI reporting on PUCCH) is configured, N sub-configurations(es) among the L sub-configurations configured via MAC-CE can be activated. Additionally, for a CSI reporting configuration in which SP CSI reporting on PUSCH or A(aperiodic)-CSI reporting is configured, N sub-configurations out of L sub-configurations configured via DCI may be triggered.

[0399]

[0400] From the perspective of a base station operating multiple frequency bands, if the number of terminals served is small or the traffic load is relatively low, periodically transmitting SSB and / or system information may result in unnecessary energy consumption. In the present disclosure, the frequency band may be replaced with a band, a carrier, a serving cell, or a bandwidth part (BWP).

[0401] For example, three frequency bands may be operated as shown in FIG. 17. FIG. 17 illustrates examples of frequency bands operated by a base station according to an embodiment of the present disclosure. Referring to FIG. 17, when a base station operates three frequency bands, the base station may periodically transmit SSB (e.g., legacy SSB) in some frequency bands (e.g., F1), transmit simplified or modified S-SSB (simplified-SSB) in the remaining frequency bands (e.g., F2), or not transmit SSB and S-SSB in other frequency bands (e.g., F3). That is, F2 and F3 may be understood as SSB-free frequency bands. Through this, the base station can save energy. A terminal operating in F2 or F3 can request SSB transmission from the base station in the corresponding frequency band. An SSB transmitted upon a request from a terminal may be referred to as an on-demand SSB, and the SSB may be a legacy SSB, or a simplified or modified S-SSB. Here, a cell that does not allow SSB transmission, such as F2 or F3, may be referred to as an SSB-less cell. From the terminal's perspective, an SSB-less cell may be any one of PCell, PSCell, or SCell.

[0402]

[0403] The base station can configure the terminal to request on-demand SSB through which of the following uplink signals and / or channels, and the terminal can request on-demand SSB through a specific uplink signal and / or channel based on the configuration from the base station. For convenience of explanation, the present disclosure refers to the uplink signal and / or channel transmitted by the terminal for requesting on-demand SSB as 'UL_SSB'.

[0404] - PRACH: For on-demand SSB requests, at least one RO (RACH occasion) may be separately configured. Alternatively, for on-demand SSB requests, some PPRACH preamble index(es) within a specific RO may be configured for on-demand SSB requests.

[0405] - SR (scheduling request) PUCCH / PRACH: When transmitting an SR corresponding to an SSB-less cell (e.g., an SR transmitted on PUCCH or PRACH), the UE may always be regarded as requesting on-demand SSB. That is, transmission of an SR corresponding to an SSB-less cell may be interpreted as a request for on-demand SSB. Alternatively, SR resources for requesting on-demand SSB may be configured separately from SR resources that do not request on-demand SSB. Here, the SR resources may include separate time / frequency resources and / or sequence resources.

[0406] - SRS: SRS resources may be separately configured to request on-demand SSB. Here, the SRS resources may include separate time / frequency resources and / or sequence resources.

[0407] - PUCCH: On-demand SSB request information can be transmitted periodically or aperiodically via a periodic or semi-persistent PUCCH. Here, the SSB request information includes information for notifying that the terminal requests transmission of on-demand SSB.

[0408] - PUSCH: On-demand SSB request information can be transmitted periodically or aperiodically via PUSCH scheduled through UL grant or via semi-static PUSCH (e.g., CG (configured grant) PUSCH or semi-static CSI-reporting on PUSCH, etc.).

[0409] - Resources for UL_SSB may be set up on a non-SSB cell. Alternatively, resources for UL_SSB may be set up on a cell other than the non-SSB cell (e.g., PCell / PSCell / SCell / non-serving cell, etc.).

[0410] The above-described on-demand SSB request procedure based on uplink signals may be implemented in a limited manner for specific cells. In one embodiment, a terminal may transmit a request signal to request on-demand SSB for a Pcell.

[0411]

[0412] One or more UL_SSB resources may be configured for a terminal. At this time, the terminal may select a UL_SSB resource according to the following conditions. Here, the UL_SSB resource(s) may be distinguished by time / frequency / sequence resources in the same uplink signal and / or channel, may be distinguished by the type of uplink signal and / or channel, or may be distinguished by the cell corresponding to the UL_SSB resource.

[0413] - Setting different UL_SSB resources by SSB index or index group: Here, the SSB index may be an index corresponding to an SSB to be transmitted on an SSB-less cell or an index corresponding to an SSB to be transmitted on a reference cell. In the present disclosure, a reference cell means a cell that is set to be interworked for at least one of timing sync and / or automatic gain control (AGC) setting of an SSB-less cell, uplink power control (UL power control), path-loss estimation, beam management-related measurements (e.g., L1-RSRP, L1-SINR, etc.) and / or RRM measurements (e.g., RSRP, RSRQ, RSSI, etc.), and may include cells other than an SSB-less cell (e.g., PCell / PSCell / SCell / non-serving cell, etc.). For example, different UL_SSB resources may be set for each SSB index or SSB index group corresponding to an SSB to be transmitted on a non-SSB cell or an SSB to be transmitted on a reference cell, and UL_SSB resource #1 corresponding to SSB index group #0 or SSB index #0 may be set in advance, and UL_SSB resource #2 corresponding to SSB index group #1 or SSB index #1 may be set in advance. If a terminal requests SSB index #1 or SSB index group #1, the terminal may transmit a signal using UL_SSB resource #2.

[0414] In one embodiment, in cases where it is unclear whether a terminal requests a specific SSB index or group of indexes, a separate UL_SSB resource may be set up to request all SSB indices. In this case, the terminal can request transmission for all SSB indices by performing uplink transmission through the UL_SSB resource.

[0415] - Set different UL_SSB resources according to the transmission duration, periodicity and / or SSB pattern of the SSB that the terminal requests: The transmission duration may mean the period from the start to the end of on-demand SSB on an SSB-free cell. For example, if on-demand SSB is transmitted P times with a period of X msec from slot#n on an SSB-free cell, and then on-demand SSB is turned off from slot#n+k and SSB is no longer transmitted, the k slot(s) or the absolute time or P value corresponding to the k slot(s) may be defined as the period. The SSB period may mean the transmission time interval or the minimum transmission time interval between SSBs or SSB candidates having the same index. In addition, when multiple SSB patterns (e.g., legacy SSB and simplified SSB) are pre-configured / defined, different UL_SSB resources may be configured for each SSB pattern. For example, when UL_SSB resource #1 corresponding to SSB transmission section #1 and UL_SSB resource #2 corresponding to SSB transmission section #2 are separately configured, the UE may select UL_SSB resource #2 according to the required SSB transmission section and perform uplink transmission using the selected UL_SSB resource #2. Accordingly, the UE may assume that on-demand SSB may be transmitted during SSB transmission section #2.

[0416] - If there is more than one reference cell corresponding to a non-SSB cell, setting different or identical UL_SSB resources for each reference cell: If multiple reference cells corresponding to a specific non-SSB cell are set, different UL_SSB resources may be set for each reference cell. For example, if a PCell and another SCell are set as reference cells for a non-SSB cell, UL_SSB resource #1 corresponding to the PCell and UL_SSB resource #2 corresponding to the other SCell may be set, and if a UE requests an SSB linked with the PCell on the non-SSB cell, uplink transmission may be performed through UL_SSB resource #1.

[0417] - When UL_SSB resources corresponding to one or more SSB-less cells are configured for a common cell, different UL-SSB resources are configured for each SSB-less cell or group of SSB-less cells: For example, when a terminal uses three serving cells through CA (carrier aggregation), both SCell#0 and SCell#1 operate as SSB-less cells, and both UL_SSB resources for requesting SSB on SCell#0 and UL_SSB resources for requesting SSB on SCell#1 can be configured on the PCell.

[0418] At this time, Opt-1) UL_SSB resource for requesting SSB on SCell#0 and UL_SSB resource for requesting SSB on SCell#1 may be set identically, or Opt-2) UL_SSB resource for requesting SSB on SCell#0 and UL_SSB resource for requesting SSB on SCell#1 may be set differently. In case of Opt-1, the UE can request transmission of on-demand SSB for both SCells by performing uplink transmission through the common UL_SSB resource. In case of Opt-2, the UE can request transmission of on-demand SSB for a specific SCell by performing uplink transmission on one of the different UL_SSB resources.

[0419] - Different UL_SSB resources are set depending on whether the SSB requested by the terminal is a NCD-SSB (non-cell defining-SSB) or a CD-SSB (cell defining-SSB): NCD-SSB refers to an SSB that does not provide CORESET index 0 and type0-PDCCH CSS set information through PBCH information, and CD-SSB refers to an SSB that provides CORESET index 0 and type0-PDCCH CSS set information through PBCH information. According to one embodiment, UL_SSB resource #1 corresponding to NCD-SSB and UL_SSB resource #2 corresponding to CD-SSB may be set separately, and if the terminal performs uplink transmission through UL_SSB resource #1, the terminal may expect that NCD-SSB can be transmitted in the corresponding SSB-less cell. On the other hand, if the terminal performs uplink transmission via UL_SSB resource #2, the terminal can expect that CD-SSB can be transmitted in the corresponding SSB-less cell.

[0420]

[0421] In general, SSB can serve as a reference signal for a terminal to obtain timing synchronization, a path-loss estimation for uplink transmission power control, and a reference signal for QCL / TCI / spatial relation information. However, since SSB is not transmitted in an SSB-less cell, it is necessary to set up an alternative signal and / or channel that performs the aforementioned role. If SSB is transmitted on the SSB-less cell in the form of on-demand SSB, the present disclosure proposes a method for providing the aforementioned role of SSB through on-demand SSB.

[0422]

[0423] FIG. 18 illustrates an example of a procedure for utilizing on-demand SSB in a wireless communication system according to an embodiment of the present disclosure. FIG. 18 illustrates a method performed by a terminal.

[0424] Referring to FIG. 18, in step S2801, the terminal performs a function for the first cell using a first signal. Here, the first signal may include a signal transmitted from the first cell, or a signal transmitted from a cell other than the first cell. For example, the other cell may include one of a non-SSB cell or a normal cell set as a reference cell for the first cell.

[0425] In step S1803, the terminal performs a function for the first cell using the second signal. Here, the second signal includes an on-demand SSB, and the on-demand SSB includes a conditional SSB transmitted from the first cell that is the target of the function performed in step S1801. When the on-demand SSB is transmitted due to a request from the terminal or the occurrence of another event, the terminal can perform the function that was being performed using the first signal using the on-demand SSB. Thereafter, although not illustrated in FIG. 18, if a given condition is satisfied, the corresponding function can be performed again using the first signal.

[0426] As described with reference to FIG. 18, a second signal including on-demand SSB may be used in place of or in conjunction with the first signal for a function performed using the first signal. In this case, according to one embodiment, the first signal may be understood as a signal transmitted on a cell other than the first cell (e.g., a reference cell). Alternatively, according to another embodiment, the first signal and the second signal may be understood as signals of the same or different types transmitted in the same cell, in which case the first signal and the second signal may be transmitted at different periods.

[0427] As described with reference to FIG. 18, specific functions can be performed using on-demand SSB. For example, the specific functions may include at least one of time synchronization acquisition, path loss estimation, parameter setting indicating channel relevance, and CSI measurement and / or reporting. Since on-demand SSB transmission is not guaranteed to always occur, control and / or management of performing the corresponding functions using on-demand SSB is required. Below, the present disclosure describes specific embodiments for each function.

[0428]

[0429] [Example #1] Method for performing timing reference function using on-demand SSB transmitted on SSB-less cell

[0430] For a terminal, one or more reference cells may be set or indicated as timing references for a non-SSB cell, and the terminal may obtain time synchronization information from the set one or more reference cells. However, according to various embodiments, an on-demand SSB transmitted in a non-SSB cell may be used as a signal for the timing reference.

[0431] FIG. 19 illustrates an example of a procedure for performing time synchronization of a non-SSB cell in a wireless communication system according to one embodiment of the present disclosure. FIG. 19 illustrates a method performed by a terminal.

[0432] Referring to FIG. 19, in step S1901, the terminal determines at least one reference cell for a non-SSB cell. For example, the terminal may determine at least one reference cell by receiving configuration information related to the reference cell from the base station. Alternatively, the terminal may determine at least one reference cell based on a predefined rule. Here, the reference cell provides a downlink signal or channel for obtaining time synchronization applicable to the non-SSB cell.

[0433] In step S1903, the terminal confirms satisfaction of a condition for time synchronization using on-demand SSB. For example, the condition may be related to at least one of a change in a situation related to on-demand SSB, such as a configuration of a base station, an SSB transmission operation in an SSB-free cell, or an SSB reception operation in an SSB-free cell. Specifically, the condition may include at least one of: on-demand SSB being transmitted; on-demand SSB transmission being maintained for a threshold time or longer; on-demand SSB transmission being performed a threshold number of times or longer; and a time synchronization function for on-demand SSB being set and / or activated.

[0434] In step S1905, the terminal performs time synchronization using on-demand SSB. That is, based on the satisfaction of the conditions for time synchronization using on-demand SSB, the terminal can perform time synchronization of an SSB-less cell where on-demand SSB is transmitted using on-demand SSB. At this time, the time period during which the time synchronization operation using on-demand SSB is valid may be limited. That is, the terminal obtains time synchronization using on-demand SSB during a configured or determined time period, and when the time period elapses, the terminal can perform time synchronization using a signal on a reference cell previously used for time synchronization or another reference cell.

[0435] As described with reference to FIG. 19, on-demand SSB transmitted from an SSB-less cell can be used as a signal for a timing reference. Below, the present disclosure describes various embodiments for an operation that utilizes an SSB-less cell as a cell that serves as a timing reference.

[0436] (Example #1-1-1) When an uplink signal and / or channel for requesting on-demand SSB in an SSB-less cell is transmitted or a signaling is received from a base station indicating that on-demand SSB is being transmitted, the terminal may receive on-demand SSB from the SSB-less cell. In this case, while receiving on-demand SSB from the SSB-less cell, the terminal may temporarily consider the SSB-less cell, which is not the reference cell, as a cell that serves as a timing reference.

[0437] (Example #1-1-1) When an uplink signal and / or channel for requesting on-demand SSB in an SSB-less cell is transmitted or a signaling is received from a base station indicating that on-demand SSB is being transmitted, the terminal may receive on-demand SSB from the SSB-less cell. In this case, while receiving on-demand SSB from the SSB-less cell, the terminal may temporarily consider the SSB-less cell, which is not the reference cell, as a cell that serves as a timing reference.

[0438] (Example #1-1-2) When an on-demand SSB is received from a corresponding SSB-less cell for a time period longer than a time interval of length T or when an SSB is received in T or more time occasions, the terminal may temporarily regard the SSB-less cell, which is not the reference cell, as a cell that serves as a timing reference. Here, the value of T may be defined in advance or may be set or indicated by the base station.

[0439] (Example #1-2) It may be configurable whether a non-reference cell, an SSB-less cell, can be regarded as a timing reference cell temporarily while receiving an on-demand SSB from the non-SSB-less cell or after receiving an on-demand SSB. For example, if the base station configures or instructs that a non-reference cell, an SSB-less cell, can be regarded as a timing reference cell, then the terminal can consider the non-reference cell, an SSB-less cell, as a timing reference cell, temporarily while receiving an on-demand SSB from the non-SSB-less cell or after receiving an on-demand SSB. Conversely, if the base station configures or instructs that a non-reference cell, an SSB-less cell, cannot be regarded as a timing reference cell, then the terminal can consider the reference cell as a timing reference cell regardless of receiving an on-demand SSB from the non-SSB-less cell.

[0440] (Example #1-3) Until the RACH corresponding to the SSB-less cell is triggered, the reference cell is maintained as a timing reference, and after the RACH corresponding to the SSB-less cell is transmitted and the random access procedure is completed, the reference cell corresponding to the timing reference can be updated. At this time, information related to the reference cell to be updated can be explicitly set or indicated by the base station, or the reference cell can be determined by a rule. For example, the rule can be defined to determine the SSB-less cell itself, the Pcell, the PSCell, the serving cell with the lowest index, or the serving cell with the highest index as the reference cell.

[0441] (Example #1-4) In the present disclosure, a reference cell and an SSB-free cell may refer to the same cell. For example, in a certain cell (e.g., a cell set as a reference cell), there may be an SSB#1 transmitted with a period of P1 ms, and an SSB#2 transmitted with a period of P2 ms on the cell may be indicated through DCI / MAC-CE / RRC signaling, etc. Here, P2 may have a value smaller than P1. That is, in this case, the SSB of the reference cell may be referred to as SSB#1, and the SSB of the SSB-free cell may be referred to as SSB#2.

[0442] Specifically, the terminal performs time synchronization via SSB#1 and checks whether a condition for time synchronization using SSB#2 is satisfied. For example, the condition may include at least one of: SSB#2 being transmitted; SSB#2 transmission being maintained for a threshold period of time or longer; SSB#2 transmission being performed a threshold number of times or longer; and a time synchronization function for SSB#2 being set and / or activated. Based on the satisfaction of the condition for time synchronization using SSB#2, the terminal may perform time synchronization for the corresponding cell using SSB#2 or using SSB and SSB#1. At this time, the time period during which the time synchronization operation using SSB#2 is valid may be limited. That is, the terminal may obtain time synchronization using SSB#2 during a set or determined time period, and when the time period has elapsed, may perform time synchronization using SSB#1, which was previously used for time synchronization.

[0443]

[0444] [Example #2] A Path Loss Estimation Method Using On-Demand SSB Transmitted on a Non-SSB Cell

[0445] When transmitting an uplink signal and / or channel, the terminal may perform path loss estimation based on a specific downlink RS, and determine a transmission power value of the uplink signal and / or channel based on the estimated path loss value. For example, the transmission power value may be determined according to TS 38.213 clause 7 of the 3GPP NR standard. At this time, the uplink signal and / or channel may be one of a PUSCH, a PUCCH, an SRS, and a PRACH. In addition, the downlink RS for path loss estimation may be one of an SSB or a CSI-RS. In addition, the downlink RS for path loss estimation corresponding to each uplink signal and / or channel may be configured or indicated via RRC signaling, MAC-CE, and / or DCI, or may be determined by a predetermined rule (e.g., an SSB used in the MIB acquisition process, an SSB linked to the transmitted PRACH, a downlink RS linked to a specific CORESET, etc.). In addition, in performing path-loss estimation, the estimated value is derived based on the difference between the power value of the downlink RS and the corresponding downlink RS reception sensitivity (e.g., RSRP), so the terminal must know the transmission power value of the corresponding downlink RS at the base station.

[0446] For a terminal, one or more reference cells or downlink RS(s) on SSB-free cells for path-loss estimation corresponding to an uplink signal and / or channel to be transmitted in an SSB-free cell may be set or instructed, and the terminal may determine a power value for the uplink signal and / or channel based on path-loss estimation using the corresponding downlink RS.

[0447] If the downlink RS(s) for path-loss estimation corresponding to the uplink signal and / or channel to be transmitted in the SSB-less cell are not configured or indicated, the SSB may be used as the downlink RS for path-loss estimation according to a predefined rule. Here, the SSB may be an SSB on a reference cell rather than an SSB on a SSB-less cell, and the reference cell may be defined in advance (e.g., a Pcell, a PSCell, another SCell belonging to an sTAG (secondary TAG), a serving cell with a lowest cell index, a serving cell with a highest cell index, or a reference cell set based on timing), or may be configured or indicated by the base station.

[0448] FIG. 20 illustrates an example of a procedure for performing time synchronization of a non-SSB cell in a wireless communication system according to an embodiment of the present disclosure. FIG. 20 illustrates a method performed by a terminal.

[0449] Referring to FIG. 20, in step S2001, the terminal determines at least one reference cell for a non-SSB cell. For example, the terminal may determine at least one reference cell by receiving configuration information related to the reference cell from the base station. Alternatively, the terminal may determine at least one reference cell based on a predefined rule. Here, the reference cell provides downlink RS(s) for estimating path loss applicable to the non-SSB cell.

[0450] In step S2003, the terminal verifies satisfaction of a condition for path loss estimation using on-demand SSB. For example, the condition may be related to at least one of a change in a situation related to on-demand SSB, such as a configuration of a base station, an SSB transmission operation in an SSB-free cell, or an SSB reception operation in an SSB-free cell. Specifically, the condition may include at least one of: on-demand SSB being transmitted; on-demand SSB transmission being maintained for a threshold time or longer; on-demand SSB transmission being performed a threshold number of times or longer; a path loss estimation function for on-demand SSB being configured and / or activated; and an SSB being configured as an RS for path loss estimation in a reference cell.

[0451] In step S2005, the terminal performs path loss estimation using on-demand SSB. That is, based on the satisfaction of the conditions for path loss estimation using on-demand SSB, the terminal can perform path loss estimation applied to determine uplink transmission power in an SSB-less cell where on-demand SSB is transmitted using on-demand SSB. At this time, the time period during which the path loss estimation operation using on-demand SSB is valid may be limited. That is, the terminal estimates the path loss using on-demand SSB during a set or determined time period, and when the time period elapses, the terminal can estimate the path loss using a signal on the reference cell previously used for path loss estimation or another reference cell.

[0452] As described with reference to FIG. 20, on-demand SSB transmitted in an SSB-less cell can be used as a signal for estimating path loss. Below, the present disclosure describes various embodiments for an operation that utilizes on-demand SSB on an SSB-less cell for path loss estimation.

[0453] (Example #2-1-1) When an uplink signal and / or channel for requesting on-demand SSB in an SSB-less cell is transmitted or a signaling is received from a base station indicating that on-demand SSB is being transmitted, the terminal may receive on-demand SSB from the SSB-less cell. While receiving on-demand SSB from the SSB-less cell, the terminal may temporarily perform path loss estimation using the on-demand SSB on the SSB-less cell instead of the downlink RS on the reference cell. In this case, the rule may be applied only when the downlink RS on the reference cell that is configured or instructed / determined is SSB. In other words, when the downlink RS on the reference cell that is configured or instructed / determined is SSB, path loss estimation using the on-demand SSB on the SSB-less cell may be performed in a limited manner.

[0454] (Example #2-1-2) When an on-demand SSB is received from a corresponding SSB-less cell for a time period longer than a length of T or when an SSB is received in T or more time occasions, the terminal may temporarily perform path loss estimation using the on-demand SSB on the SSB-less cell rather than the downlink RS on the reference cell. Here, the value of T may be defined in advance or may be set or indicated by the base station.

[0455] (Embodiment #2-2) It may be configurable whether path loss estimation can be performed using the on-demand SSB on the SSB-free cell rather than the downlink RS on the reference cell, either temporarily while the UE receives the on-demand SSB from the SSB-free cell or after receiving the on-demand SSB. Alternatively, whether path loss estimation can be performed using the on-demand SSB on the SSB-free cell rather than the downlink RS on the reference cell may be explicitly indicated via MAC-CE / DCI, etc. In this case, the rule may be applied only when the downlink RS on the reference cell that is configured, indicated, or determined is SSB. In other words, when the downlink RS on the reference cell that is configured or indicated / determined is SSB, whether path loss estimation can be performed using the on-demand SSB on the SSB-free cell may be limitedly configured / indicated. For example, if the base station is configured or instructed to perform path loss estimation using an on-demand SSB on an SSB-less cell rather than a downlink RS on a reference cell, the terminal may temporarily perform path loss estimation using the on-demand SSB on the SSB-less cell rather than the downlink RS on the reference cell while receiving an on-demand SSB from the SSB-less cell, or after receiving the on-demand SSB. Conversely, if the base station is configured or instructed to not perform path loss estimation using the on-demand SSB on the SSB-less cell rather than the downlink RS on the reference cell, the terminal may perform path loss estimation using the downlink RS on the reference cell regardless of receiving an on-demand SSB from the SSB-less cell.

[0456] (Example #2-3) Until the RACH corresponding to the SSB-less cell is triggered, the path-loss estimation using the downlink RS on the reference cell is maintained, and after the RACH corresponding to the SSB-less cell is transmitted and the random access procedure is completed, the reference cell and the downlink RS on the reference cell for performing the path-loss estimation can be updated. At this time, the updated reference cell and the downlink RS information on the reference cell can be explicitly set or indicated by the base station. Alternatively, the reference cell and the downlink RS on the reference cell can be determined by a rule.

[0457] (Example #2-4) In the present disclosure, a reference cell and an SSB-free cell may refer to the same cell. For example, in a certain cell (e.g., a cell set as a reference cell), there may be an SSB#1 transmitted with a period of P1 ms, and an SSB#2 transmitted with a period of P2 ms on the cell may be indicated through DCI / MAC-CE / RRC signaling, etc. Here, P2 may have a value smaller than P1. That is, in this case, the SSB of the reference cell may be referred to as SSB#1, and the SSB of the SSB-free cell may be referred to as SSB#2.

[0458] Specifically, the terminal performs path-loss estimation via SSB#1, while checking whether a condition for path-loss estimation using SSB#2 is satisfied. For example, the condition may include at least one of: SSB#2 is transmitted; SSB#2 transmission is maintained for a threshold time or longer; SSB#2 transmission is performed a threshold number of times or longer; and a path-loss estimation function for SSB#2 is set and / or activated. Based on the satisfaction of the condition for path-loss estimation using SSB#2, the terminal may perform path-loss estimation of the corresponding cell using SSB#2 or using SSB#2 and SSB#1. At this time, the time period during which the path-loss estimation operation using SSB#2 is valid may be limited. That is, the terminal may perform path-loss estimation using SSB#2 during a set or determined time period, and when the time period has elapsed, may perform path-loss estimation using SSB#1, which was previously used for path-loss estimation.

[0459]

[0460] [Example #3] RS (reference signal) setting method for QCL / TCI / spatial relation information for on-demand SSB transmitted on SSB-less cell

[0461] In setting parameters indicating channel relevance for downlink signals, uplink signals, and / or channels received or transmitted on a non-SSB cell (e.g., TCI state, TCI uplink state, and / or spatial relevance information), a downlink signal or uplink signal used as a QCL source or RS (reference signal) is required. At this time, at least one of the following signals may be set as a QCL source.

[0462] - SSB on SSB-less cells

[0463] - Other downlink or uplink signals other than SSB on a non-SSB cell (e.g., other signals on a non-SSB cell)

[0464] - Downlink or uplink signals on cells other than SSB-free cells

[0465] Since SSBs on SSB-less cells may not be transmitted during certain time intervals, using only SSBs on SSB-less cells as QCL sources may result in a gap in the QCL source. Therefore, the present disclosure proposes the following embodiment for controlling the QCL source.

[0466]

[0467] FIG. 21 illustrates an example of a procedure for setting parameters indicating channel relevance of a non-SSB cell in a wireless communication system according to an embodiment of the present disclosure. FIG. 21 illustrates a method performed by a terminal. In the following description, a QCL source may be referred to as a reference signal.

[0468] Referring to FIG. 21, in step S2101, the terminal uses a signal other than on-demand SSB as a QCL source. The QCL source may be referenced as a signal having a QCL relationship when configuring a parameter indicating channel relevance (hereinafter referred to as a "channel relevance parameter"), for example, a TCI state, an uplink TCL state, or spatial relevance information. Accordingly, when transmitting or receiving a signal linked to a channel relevance parameter, the terminal may perform transmission or reception based on the channel of the signal used as the QCL source (e.g., configuring a spatial domain filter, etc.). At this time, the QCL source may be indicated separately from the setting of the channel relevance parameter or may be indicated as part of the setting information of the channel relevance parameter. At this time, a signal other than on-demand SSB may be referenced as a QCL source. That is, a signal other than on-demand SSB from a base station may be indicated as a QCL source.

[0469] In step S2103, the terminal verifies satisfaction of a condition for using on-demand SSB as a QCL source. For example, the condition may be related to at least one of a change in a situation related to on-demand SSB in a non-SSB cell, a configuration of a base station, an SSB transmission operation in the non-SSB cell, or an SSB reception operation in the non-SSB cell. Specifically, the condition may include at least one of: on-demand SSB being transmitted; on-demand SSB transmission being maintained for a threshold time or longer; on-demand SSB transmission being performed a threshold number of times or longer; and a function for setting channel relevance parameters using on-demand SSB being set and / or activated.

[0470] In step S2105, the terminal uses the on-demand SSB as a QCL source. That is, the terminal refers to the on-demand SSB as a signal having a QCL relationship indicated by the channel relationship parameter. To this end, the terminal may perform measurements on the on-demand SSB(s). Accordingly, when transmitting or receiving a signal linked to the channel relationship parameter, the terminal may perform transmission or reception based on the channel of the on-demand SSB (e.g., configuring a spatial domain filter, etc.). At this time, the effective time period for using the on-demand SSB as a QCL source may be limited. That is, the terminal uses the on-demand SSB as a QCL source during a configured or determined time period, and when the time period elapses, the previously used signal may be used as a QCL source again.

[0471] As described with reference to FIG. 21, on-demand SSB transmitted in a non-SSB cell can be used as a QCL source. Here, using on-demand SSB as a QCL source can be understood as having the same value indicating the QCL source in the channel correlation parameter, but with a different interpretation of the value. In other words, the difference between using a signal other than on-demand SSB as a QCL source and using on-demand SSB as a QCL source may lie in the interpretation of the value indicating the QCL source in the channel correlation parameter.

[0472] Alternatively, using on-demand SSB as a QCL source may be understood as setting a value indicating a QCL source in the channel relevance parameter to at least one of the values ​​for on-demand SSB. In other words, the difference between using a signal other than on-demand SSB as a QCL source and using on-demand SSB as a QCL source may lie in the range or candidates of values ​​indicating a QCL source in the channel relevance parameter. Accordingly, in order to change the signal used as a QCL source, the terminal may receive configuration information for the channel relevance parameter referencing on-demand SSB as a QCL source.

[0473] Figure 22 illustrates an example of a procedure for receiving a signal using QCL estimation in a wireless communication system according to an embodiment of the present disclosure. Figure 22 illustrates a method performed by a terminal. In the following description, the QCL source may be referred to as a reference signal.

[0474] Referring to FIG. 22, in step S2201, the terminal receives configuration information related to TCI. Here, the configuration information is information related to QCL for signal transmission and / or reception in the first cell, and may include a first signal. In addition, the first signal may include one of a signal other than on-demand SSB on the first cell or a signal on a second cell different from the first cell.

[0475] In step S2203, the terminal receives a downlink signal or channel on the first cell by applying a QCL assumption of the first signal or the second signal based on whether an on-demand SSB is received on the first cell. For example, the terminal may receive a downlink signal or channel on the first cell by applying the QCL assumption of the on-demand SSB if it confirms at least one of the following: that an on-demand SSB is transmitted, that the transmission of the on-demand SSB is maintained for a threshold time or longer, or that the transmission of the on-demand SSB is performed a threshold number of times or longer. On the other hand, if the on-demand SSB is not transmitted, the terminal may apply the QCL assumption of the first signal.

[0476] Hereinafter, the present disclosure describes various embodiments related to setting channel relevance parameters in SSB-less cells.

[0477] (Example #3-1) A terminal may use a downlink signal or uplink signal other than SSB on an SSB-free cell (e.g., another signal on an SSB-free cell or a signal on another cell) as a QCL source, and may use the on-demand SSB as a QCL source temporarily while receiving an on-demand SSB from the SSB-free cell or after receiving the on-demand SSB. In this case, the rule may be applied only when the downlink RS set as a QCL source other than SSB on the SSB-free cell is SSB. In other words, when the downlink RS set as a QCL source other than SSB on the SSB-free cell is SSB, setting of channel relevance parameters (e.g., QCL, TCI and / or spatial relevance information) using on-demand SSB on the SSB-free cell may be permitted with restrictions.

[0478] (Example #3-2) When an on-demand SSB is received from a non-SSB cell for a time period longer than a length of T or when an SSB is received in T or more time occasions, the terminal may temporarily use the on-demand SSB on the non-SSB cell as a QCL source. Here, the value of T may be defined in advance or may be set or indicated by the base station.

[0479] (Example #3-3) It may be configurable whether to change the QCL source depending on whether on-demand SSB transmission is performed on a non-SSB cell. That is, the terminal may receive configuration information regarding whether to use on-demand SSB as a QCL source based on a change in the situation related to on-demand SSB.

[0480] (Example #3-4) Channel relevance parameters may be managed as a list or set. In this case, depending on the QCL source used, the list or set of channel relevance parameters may be interpreted differently, or different lists or different sets may be used.

[0481] FIG. 23 illustrates an example of a procedure for applying channel correlation parameters based on a QCL source in a wireless communication system according to an embodiment of the present disclosure. FIG. 23 illustrates a method performed by a terminal.

[0482] Referring to FIG. 23, in step S2301, the terminal applies the first list while a signal other than on-demand SSB is used as a QCL source. Here, the first list includes a correspondence between indices of channel correlation parameters and signals used as QCL sources. That is, each indices of the channel correlation parameters is associated with one of the signals used as a QCL source, and the first list expresses the correlation between the indices of the channel correlation parameters and the signals used as QCL sources. Accordingly, when an index of a specific channel correlation parameter is set for a signal transmitted or received by the terminal, the terminal can determine that the signal associated with the set index and the corresponding transmitted or received signal have a QCL relationship. At this time, the terminal confirms the signal associated with the set index based on the first list.

[0483] In step S2303, the terminal applies a second list while the on-demand SSB is used as a QCL source. Here, the second list includes indices of channel correlation parameters and correspondences between signals used as QCL sources, and can express a correlation with a QCL source different from the first list. That is, the second list may be a list generated using the on-demand SSB as a QCL source. Accordingly, when an index of a specific channel correlation parameter is set for a signal transmitted or received by the terminal, the terminal can check a signal associated with the index based on the second list, and determine that the checked signal and the corresponding transmitted or received signal have a QCL relationship.

[0484] More specific examples of the embodiment described with reference to FIG. 23 are as follows.

[0485] Sets of different TCI states / TCI uplink states / spatial relation information values ​​may be configured, and one of the sets may be adaptively applied depending on whether on-demand SSB is received from an SSB-less cell. Specifically, for TCI states / TCI uplink states / spatial relation information values ​​managed as a list (e.g., tci-StatesPDCCH-ToAddList, tci-StatesToAddModList, DL-OrJointTCI-StateToAddModList, ul-TCI-ToAddModList, spatialRelationInfoToAddModList), multiple lists may be configured, and a different list may be activated depending on whether on-demand SSB is received from an SSB-less cell. At this time, a TCI state index / TCI uplink state index / spatial relation information index may be determined based on the activated list, and a value corresponding to the determined index may be applied to a corresponding downlink signal, uplink signal, and / or channel. To this end, according to one embodiment, the terminal may receive configuration information related to a list of channel related parameters from the base station, a first list for a first case in which a signal other than on-demand SSB is used as a QCL source, and a second list for a second case in which on-demand SSB is used as a QCL source.

[0486] Alternatively, the list of TCI states / TCI uplink states / spatial correlation information values ​​may be maintained as single, and the components included in the list may be configured and applied differently depending on whether on-demand SSB is received from an SSB-less cell. For example, TCI state index(es) linked to a PDSCH may be configured or indicated via RRC signaling and / or MAC CE, and the UE may apply different TCI state indexes to receive the corresponding PDSCH depending on whether on-demand SSB is received. For example, the TCI state index(es) corresponding to each code-point of a field indicating TCI in a DCI format may be configured or indicated differently depending on whether on-demand SSB is received. Specifically, if TCI state indices {#0,#2,#4} are mapped to each code point in case #A, and TCI state indices {#1,#3,#5} are mapped to each code point in case #B, then when interpreting the TCI field in the DCI format, the terminal can assume that TCI state indices {#0,#2,#4} are mapped to each code point in case #A, and can assume that TCI state indices {#1,#3,#5} are mapped to each code point in case #B. The mapping relationship between the code points and the TCI state indices can be indicated through a common MAC CE or each case-by-case. Here, case #A can be during or after receiving an on-demand SSB from the SSB-less cell, and case #B can mean the remaining situations.

[0487] (Example #3-5) In the present disclosure, a signal other than an on-demand SSB may refer to another SSB transmitted on the same cell. For example, there may be an SSB#1 transmitted with a period of P1 ms in a certain cell, and an SSB#2 transmitted with a period of P2 ms on the cell may be indicated through DCI / MAC-CE / RRC signaling, etc. Here, P2 may have a value smaller than P1. That is, in this case, a signal other than an on-demand SSB may be referred to as SSB#1, and an SSB of a non-SSB cell may be referred to as SSB#2.

[0488] Specifically, the terminal uses SSB#1 as a QCL source and checks whether a condition is satisfied for whether SSB#2 can be used as a QCL source. For example, the condition may include at least one of: SSB#2 being transmitted; transmission of SSB#2 being maintained for a threshold time or longer; transmission of SSB#2 being performed a threshold number of times or longer; and SSB#2 being configured and / or activated for use as a QCL source. Based on the satisfaction of the condition for using SSB#2 as a QCL source, the terminal may use SSB#2 or both SSB#2 and SSB#1 as QCL sources. At this time, the time period during which the operation of using SSB#2 as a QCL source is valid may be limited. That is, the terminal uses SSB#2 as a QCL source during the configured or determined time period, and when the time period elapses, it may use SSB#1, which was previously used as a QCL source.

[0489]

[0490] [Example #4] CSI reporting method for a cell without SSB when the cell is activated.

[0491] According to TS 38.213 Section 4.3, when a SCell is activated, a CSI report for the SCell should be performed after a certain time (e.g., 3 msec or 3 msec + 1 slot) has elapsed after the receipt of the MAC-CE indicating the activation and the transmission of the corresponding HARQ-ACK. However, in the case of a non-SSB cell, since SSB may not be transmitted, it may be acceptable for the cell not to perform CSI reporting even after it has been activated. In this case, the base station can indirectly determine the channel status of the non-SSB cell using the CSI report from the reference cell.

[0492] In other words, even if a certain SCell is configured or instructed to operate as a non-SSB cell and the SCell is activated via MAC-CE, the UE may not perform CSI reporting for the non-SSB cell. Alternatively, whether to perform CSI reporting for the non-SSB cell after activation may be configured in advance. Alternatively, whether to perform CSI reporting for the non-SSB cell after activation may be indicated by the MAC-CE that instructs activation or a separate MAC-CE or DCI.

[0493] Even if CSI reporting is not performed after activation for the corresponding SSB-less cell, CSI reporting for the corresponding SSB-less cell may be performed after the UE receives an on-demand SSB. Alternatively, CSI reporting for the corresponding SSB-less cell may be performed after receiving a separate configuration or instruction.

[0494]

[0495] FIG. 24 illustrates an example of a procedure for utilizing on-demand SSB in an SSB-less cell in a wireless communication system according to one embodiment of the present disclosure. FIG. 24 illustrates signal exchange between a terminal (2310) and a base station (2320).

[0496] Referring to FIG. 24, in step S2401, the base station (2420) can set a non-SSB cell, a reference cell, an on-demand SSB, etc. In step S2403, the terminal (2410) performs timing information acquisition and / or path-loss estimation, etc. based on the reference cell. In step S2405, the terminal (2410) can select and transmit one of the configured on-demand SSB signals. Accordingly, the base station (2420) receives the corresponding on-demand SSB signal. Thereafter, in step S2407, the base station (2420) transmits the corresponding SSB signal. At this time, as in the above-described [Example #1] and / or [Example #2], in step S2409, the terminal (2410) can perform timing information and / or path-loss estimation, etc. based on the non-SSB cell instead of the reference cell.

[0497]

[0498] When there are multiple frequency bands operated by a base station, for the purpose of NES, SSB and / or system information may be periodically transmitted only in a specific frequency band, and the corresponding signals and / or channels may not be periodically transmitted in the remaining frequency bands. In order to support such operation of the base station and stable communication of the terminal in the corresponding frequency band, the present disclosure proposes embodiments for various functions based on operation based on on-demand SSB, specifically, on-demand SSB transmitted on an SSB-free cell.

[0499] In an SSB-less cell, on-demand SSB can be transmitted at the request of a terminal or at the judgment of a base station. In this case, even a cell supporting on-demand SSB can transmit an always-on SSB (hereinafter referred to as a "default SSB") that is different from the on-demand SSB. In this case, the base station can transmit the default SSB in the cell and additionally transmit the on-demand SSB at the request of a terminal or at the judgment of the base station. In other words, an SSB-less cell refers to the cell from the perspective of on-demand SSB, and if there is a state in which on-demand SSB is not transmitted at a certain point in time even when the default SSB is transmitted, the cell can be referred to as an SSB-less cell.

[0500] Accordingly, the embodiments applied to the aforementioned non-SSB cell can be similarly applied to a cell that transmits a default SSB and supports on-demand SSB. In this case, in the various embodiments described above, the reference cell and the non-SSB cell can be understood as a single cell that supports on-demand SSB, and the signal of the reference cell can be replaced with the default SSB of the cell that supports on-demand SSB.

[0501]

[0502] The proposed methods described above can be implemented independently, but they can also be implemented as a combination (or merge) of some of the proposed methods. Rules can be defined so that the base station notifies the terminal of the applicability of the proposed methods (or information about the rules of the proposed methods) through a predefined signal (e.g., a physical layer signal or a higher layer signal).

[0503] The present disclosure may be embodied in other specific forms without departing from the technical ideas and essential features described herein. Therefore, the above detailed description should not be construed as limiting in all respects but rather as illustrative. The scope of the present disclosure should be determined by a reasonable interpretation of the appended claims, and all modifications within the equivalent scope of the present disclosure are intended to be included within the scope of the present disclosure. Furthermore, claims that are not explicitly cited in the claims may be combined to form an embodiment or incorporated into a new claim through a post-filing amendment.

[0504] Embodiments of the present disclosure can be applied to various wireless access systems. Examples of various wireless access systems include the 3rd Generation Partnership Project (3GPP) or 3GPP2 systems.

[0505] The embodiments of the present disclosure can be applied not only to the various wireless access systems described above, but also to all technical fields that utilize these various wireless access systems. Furthermore, the proposed method can also be applied to mmWave and THz communication systems utilizing ultra-high frequency bands.

[0506] Additionally, embodiments of the present disclosure can be applied to various applications such as autonomous vehicles and drones.

Claims

1. In the method, A step of receiving configuration information related to a transmission configuration indication (TCI), wherein the configuration information includes a first signal as information related to a QCL (quasi-colocated); a step of receiving a second signal on a first cell; A step of receiving a downlink signal or channel on the first cell by applying the QCL assumption of the second signal, A method wherein the second signal comprises an on-demand SSB (synchronization signal / physical broadcast channel block) on the first cell.

2. In claim 1, A method wherein the first signal comprises one of a signal other than the second signal on the first cell or a signal on the second cell.

3. In claim 1, The step of receiving a downlink signal or channel on the first cell by applying QCL estimation of the second signal is: A method comprising the step of receiving a downlink signal or channel on the first cell by applying QCL estimation of the second signal based on at least one of the following: the second signal being transmitted in the first cell, the transmission of the second signal being maintained for a threshold time or longer, or the transmission of the second signal being performed a threshold number of times or longer.

4. In claim 1, A method further comprising the step of receiving setting information related to whether to apply QCL estimation of the second signal based on reception of the second signal.

5. In claim 1, The step of receiving a downlink signal or channel on the first cell by applying QCL estimation of the second signal is: A method comprising the step of applying QCL estimation of the second signal based on the first signal including SSB on the second cell.

6. In claim 1, The first signal comprises at least one SSB on the first cell, A method wherein the at least one SSB is set to be transmitted with a relatively longer period than the on-demand SSB.

7. In claim 1, The step of receiving a downlink signal or channel on the first cell by applying QCL estimation of the second signal is: A method comprising a step of applying transmission configuration information (TCI) information or spatial relation information included in a list set for the second signal to the signal.

8. In claim 1, A method further comprising the step of receiving configuration information related to a first list of TCI states for a first case in which QCL estimation of the first signal is applied and a second list of TCI states for a second case in which QCL estimation of the second signal is applied.

9. In claim 1, The step of receiving a downlink signal or channel on the first cell by applying QCL estimation of the second signal is: A method comprising a step of applying TCI information identified based on a mapping relationship between code points and TCI state indices of a TCI field of downlink control information (DCI) defined for the second signal.

10. In claim 1, A step of obtaining time synchronization using a signal on a reference cell for the first cell; A method comprising the step of obtaining time synchronization using the on-demand SSB on the first cell based on reception of the second signal.

11. In claim 1, A step of estimating path-loss using a signal on a reference cell for the first cell; A method comprising the step of estimating the path loss using the on-demand SSB on the first cell based on reception of the second signal.

12. In claim 1, A step of receiving a message related to the activation of the first cell; and A method further comprising the step of transmitting a CSI (channel state information) report for the first cell after receiving the on-demand SSB of the first cell.

13. In the method, A step of transmitting configuration information related to a transmission configuration indication (TCI), wherein the configuration information includes a first signal as information related to a QCL (quasi-colocated); A step of transmitting a downlink signal or channel on the first cell by applying a QCL assumption of the second signal based on transmission of the second signal on the first cell, A method wherein the second signal comprises an on-demand SSB (synchronization signal / physical broadcast channel block) on the first cell.

14. In claim 13, A method wherein the first signal comprises one of a signal other than the second signal on the first cell or a signal on the second cell.

15. In claim 13, The step of transmitting a downlink signal or channel on the first cell by applying the QCL estimation of the second signal is: A method comprising the step of transmitting a downlink signal or channel on the first cell by applying QCL estimation of the second signal based on at least one of the second signal being transmitted, the transmission of the second signal being maintained for a threshold time or longer, or the transmission of the second signal being performed a threshold number of times or longer.

16. In claim 13, The step of transmitting a downlink signal or channel on the first cell by applying the QCL estimation of the second signal is: A method comprising the step of applying QCL estimation of the second signal based on the first signal including SSB on the second cell.

17. In claim 13, The first signal comprises at least one SSB on the first cell, A method wherein the at least one SSB is set to be transmitted with a relatively longer period than the on-demand SSB.

18. In claim 13, A method further comprising the step of transmitting configuration information related to a first list of TCI states for a first case in which QCL estimation of the first signal is applied and a second list of TCI states for a second case in which QCL estimation of the second signal is applied.

19. In the device, Transmitter and receiver; and A processor connected to the above transmitter and receiver is included, The above processor, Receive configuration information related to TCI (transmission configuration indication), wherein the configuration information includes a first signal as information related to QCL (quasi-colocated), Receive a second signal on the first cell, It is configured to receive a downlink signal or channel on the first cell by applying the QCL assumption of the second signal, A device wherein the second signal includes an on-demand SSB (synchronization signal / physical broadcast channel block) on the first cell.

20. In the device, Transmitter and receiver; and A processor connected to the above transmitter and receiver is included, The above processor, Transmits configuration information related to TCI (transmission configuration indication), wherein the configuration information includes the first signal as information related to QCL (quasi-colocated), Based on the transmission of a second signal on a first cell, a downlink signal or channel on the first cell is configured to be transmitted by applying a QCL assumption of the second signal, A device wherein the second signal includes an on-demand SSB (synchronization signal / physical broadcast channel block) on the first cell.

21. At the terminal, At least one processor; At least one memory connected to the at least one processor and storing instructions that cause the terminal to perform operations when executed by the at least one processor, The above actions are, A step of receiving configuration information related to a transmission configuration indication (TCI), wherein the configuration information includes a first signal as information related to a QCL (quasi-colocated); a step of receiving a second signal on a first cell; A step of receiving a downlink signal or channel on the first cell by applying the QCL assumption of the second signal, The second signal is a terminal including an on-demand SSB (synchronization signal / physical broadcast channel block) on the first cell.

22. In a non-transitory computer-readable medium storing at least one program instruction, wherein said at least one program instruction, when executed by at least one processor, causes the terminal to perform operations; The above actions are, A step of receiving configuration information related to a transmission configuration indication (TCI), wherein the configuration information includes a first signal as information related to a QCL (quasi-colocated); a step of receiving a second signal on a first cell; A step of receiving a downlink signal or channel on the first cell by applying the QCL assumption of the second signal, A computer-readable medium comprising the second signal, an on-demand SSB (synchronization signal / physical broadcast channel block) on the first cell.

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