WO2025116644A1 - Method and apparatus for utilizing on-demand synchronization signal block in wireless communication system - Google Patents

Abstract

A method and an apparatus for utilizing an on-demand synchronization signal block in a wireless communication system are disclosed. A method performed by a terminal in a wireless communication system according to one embodiment of the present disclosure comprises the steps of: receiving, in a first cell, a configuration for an on-demand synchronization signal block in a second cell; receiving indication information related to the on-demand synchronization signal block; performing measurement on the on-demand synchronization signal block on the basis of the on-demand synchronization signal block being transmitted on the basis of at least one of the configuration and the indication information, and reporting information on a measurement result. Here, the on-demand synchronization signal block can be transmitted for a predetermined period after the indication information is received.

Description

Method and device for utilizing on-demand synchronization signal blocks in wireless communication systems

The present disclosure relates to a wireless communication system, and more particularly, to a method and apparatus for utilizing an on-demand synchronization signal block (SSB) in a wireless communication system.

Mobile communication systems were developed to provide voice services while ensuring user activity. However, mobile communication systems have expanded their scope to include data services as well as voice, and currently, due to the explosive increase in traffic, resource shortages are occurring and users are demanding higher-speed services, so more advanced mobile communication systems are required.

The requirements for the next generation mobile communication system are that it should be able to accommodate explosive data traffic, dramatically increase the data rate per user, accommodate a greatly increased number of connected devices, support very low end-to-end latency, and support high energy efficiency. To this end, various technologies are being studied, including dual connectivity, massive multiple input multiple output (MIMO), in-band full duplex, non-orthogonal multiple access (NOMA), super wideband support, and device networking.

The technical problem of the present disclosure is to provide a method and device for utilizing an on-demand synchronization signal block (SSB) in a wireless communication system.

The technical problems to be achieved in the present disclosure are not limited to the technical problems mentioned above, and other technical problems not mentioned will be clearly understood by a person having ordinary skill in the technical field to which the present disclosure belongs from the description below.

A method performed by a terminal in a wireless communication system according to one aspect of the present disclosure may include: receiving, in a first cell, a setting for an on-demand synchronization signal block in a second cell; receiving indication information related to the on-demand synchronization signal block; and reporting information on a measurement result for the on-demand synchronization signal block based on at least one of the setting or the indication information, wherein the on-demand synchronization signal block may be transmitted for a predetermined period after reception of the indication information.

A method performed by a base station in a wireless communication system according to an additional aspect of the present disclosure may include: transmitting, in a first cell, a configuration for an on-demand synchronization signal block in a second cell; transmitting indication information related to the on-demand synchronization signal block; and receiving a report including information on a measurement result for the on-demand synchronization signal block based on at least one of the configuration or the indication information, wherein the on-demand synchronization signal block may be transmitted for a predetermined period after reception of the indication information.

According to various embodiments of the present disclosure, a method and apparatus for utilizing an on-demand synchronization signal block (SSB) in a wireless communication system can be provided.

By various embodiments of the present disclosure, there is a technical effect of reducing base station energy waste due to SSB transmission by enabling a terminal to support SCell measurement via on-demand SSB.

The effects obtainable from the present disclosure are not limited to the effects mentioned above, and other effects not mentioned will be clearly understood by a person having ordinary skill in the art to which the present disclosure belongs from the description below.

The accompanying drawings, which are incorporated in and are incorporated in and are intended to aid in understanding the present disclosure, provide embodiments of the present disclosure and together with the detailed description, describe the technical features of the present disclosure.

Figure 1 illustrates the structure of a wireless communication system to which the present disclosure can be applied.

FIG. 2 illustrates a frame structure in a wireless communication system to which the present disclosure can be applied.

FIG. 3 illustrates a resource grid in a wireless communication system to which the present disclosure can be applied.

FIG. 4 illustrates a physical resource block in a wireless communication system to which the present disclosure can be applied.

FIG. 5 illustrates a slot structure in a wireless communication system to which the present disclosure can be applied.

FIG. 6 illustrates physical channels used in a wireless communication system to which the present disclosure can be applied and a general signal transmission and reception method using the same.

FIG. 7 illustrates an SSB transmission method of a base station operating multiple frequency bands that can be applied to the present disclosure.

Figure 8 illustrates an on-demand SSB related procedure applicable to the present disclosure.

FIG. 9 is a drawing for explaining the operation of a terminal according to one embodiment of the present disclosure.

FIG. 10 is a diagram for explaining the operation of a base station according to one embodiment of the present disclosure.

FIG. 11 illustrates a block diagram of a wireless communication device according to one embodiment of the present disclosure.

Hereinafter, preferred embodiments according to the present disclosure will be described in detail with reference to the accompanying drawings. The detailed description set forth below together with the accompanying drawings is intended to explain exemplary embodiments of the present disclosure and is not intended to represent the only embodiments in which the present disclosure may be practiced. The following detailed description includes specific details in order to provide a thorough understanding of the present disclosure. However, one of ordinary skill in the art will appreciate that the present disclosure may be practiced without these specific details.

In some cases, to avoid obscuring the concepts of the present disclosure, well-known structures and devices may be omitted or illustrated in block diagram format focusing on the core functions of each structure and device.

In the present disclosure, when a component is said to be "connected", "coupled" or "connected" to another component, this may include not only a direct connection relationship, but also an indirect connection relationship in which another component exists between them. Also, the terms "comprises" or "has" in the present disclosure specify the presence of the mentioned features, steps, operations, elements and/or components, but do not exclude the presence or addition of one or more other features, steps, operations, elements, components and/or groups thereof.

In this disclosure, the terms “first,” “second,” etc. are used only to distinguish one component from other components and are not used to limit the components, and do not limit the order or importance among the components unless specifically stated otherwise. Accordingly, within the scope of this disclosure, a first component in one embodiment 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.

The terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the scope of the claims. As used in the description of the embodiments and the appended claims, the singular forms "a," "an," and "the" are intended to include the plural forms as well, unless the context clearly dictates otherwise. The term "and/or" as used herein may refer to one of the associated enumerated items or is meant to refer to and encompass any and all possible combinations of two or more of them. Furthermore, the word "/" used between words in this disclosure has the same meaning as "and/or" unless otherwise stated.

The present disclosure describes a wireless communication network or a wireless communication system, and an operation performed in a wireless communication network may be performed in a process of controlling the network and transmitting or receiving a signal from a device (e.g., a base station) that manages the wireless communication network, or in a process of transmitting or receiving a signal with or between terminals connected to the wireless network.

In the present disclosure, transmitting or receiving a channel means transmitting or receiving information or a signal through the channel. For example, transmitting a control channel means transmitting control information or a signal through the control channel. Similarly, transmitting a data channel means transmitting data information or a signal through the data channel.

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

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

The technology described in this specification can be implemented with 6G wireless technology and can be 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.

For the sake of clarity, the description is based on 3GPP communication systems (e.g., LTE-A, NR, 6G), but the technical idea of the present disclosure is not limited thereto. LTE refers to technology after 3GPP TS (Technical Specification) 36.xxx Release 8. Specifically, LTE technology after 3GPP TS 36.xxx Release 10 is referred to as LTE-A, and LTE technology after 3GPP TS 36.xxx Release 13 is referred to as LTE-A pro. 3GPP NR refers to technology after TS 38.xxx Release 15. LTE/NR/6G may be referred to as a 3GPP system. “xxx” refers to a standard document detail number. LTE/NR/6G may be collectively referred to as a 3GPP system. With respect to background technologies, terms, abbreviations, etc. used in the description of the present disclosure, reference may be made to matters described in standard documents published prior to the present disclosure. For example, reference may be made to the following documents:

For 3GPP LTE, see TS 36.211 (Physical channels and modulation), TS 36.212 (Multiplexing and channel coding), TS 36.213 (Physical layer procedures), TS 36.300 (General description) and TS 36.331 (Radio resource control).

For 3GPP NR, see TS 38.211 (Physical channels and modulation), TS 38.212 (Multiplexing and channel coding), TS 38.213 (Physical layer procedures for control), TS 38.214 (Physical layer procedures for data), TS 38.300 (Overall description of NR and New Generation-Radio Access Network (NG-RAN)), and TS 38.331 (Radio Resource Control Protocol Specification).

The abbreviations of terms that may be used in this disclosure are defined as follows.

- BM: beam management

- CQI: channel quality indicator

- CRI: Channel state information - reference signal resource indicator

- CSI: channel state information

- CSI-IM: Channel state information - interference measurement

- CSI-RS: Channel state information - reference signal

- DMRS: Demodulation reference signal

- FDM: Frequency division multiplexing

- FFT: fast Fourier transform

- IFDMA: interleaved frequency division multiple access

- IFFT: inverse fast Fourier transform

- L1-RSRP: Layer 1 reference signal received power

- L1-RSRQ: Layer 1 reference signal received quality

- MAC: Medium Access Control

- NZP: non-zero power

- OFDM: Orthogonal frequency division multiplexing

- PDCCH: physical downlink control channel

- PDSCH: physical downlink shared channel

- PMI: precoding matrix indicator

- RE: resource element

- RI: Rank indicator

- RRC: radio resource control

- RSSI: received signal strength indicator

- Rx: Reception

- QCL: quasi co-location

- SINR: signal to interference and noise ratio

- SSB (or SS/PBCH block): Synchronization signal block (including primary synchronization signal (PSS), secondary synchronization signal (SSS), and physical broadcast channel (PBCH))

- TDM: time division multiplexing

- TRP: transmission and reception point

- TRS: Tracking reference signal

- Tx: transmission

- UE: user equipment

- ZP: zero power

System General

As more and more communication devices require greater communication capacity, there is a growing need for improved mobile broadband communication over existing radio access technology (RAT). In addition, massive MTC (machine type communications), which connects a large number of devices and objects to provide various services anytime and anywhere, is also one of the major issues to be considered in next-generation communications. In addition, a communication system design that considers services/terminals that are sensitive to reliability and latency is being discussed. The introduction of next-generation RATs that consider enhanced mobile broadband communication (eMBB), massive MTC (MMTC), ultra-reliable and low latency communication (URLLC), etc. is being discussed, and in this disclosure, the technology is referred to as NR for convenience. NR is an expression indicating an example of 5G RAT.

As mentioned above, the NR system is a new clean-slate type mobile communication system that is a successor technology to LTE (long term evolution) and has the characteristics of high performance, low latency, and high availability. In the case of the NR system, all available spectrum resources can be utilized, such as the low frequency band below 1 GHz, the intermediate frequency band between 1 GHz and 10 GHz, and the high frequency (millimeter wave) band above 24 GHz. The 6G mobile communication system (hereinafter, 6G system) is being developed based on the basic technology of the NR system.

6G systems aim 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 6G systems can be divided into four aspects: intelligent connectivity, deep connectivity, holographic connectivity, and ubiquitous connectivity.

New RAT systems including NR systems and 6G systems (hereinafter, referred to as next-generation RAT systems) use OFDM transmission schemes or similar transmission schemes. The next-generation RAT system may follow OFDM parameters different from OFDM parameters of LTE. Or, the next-generation RAT system may follow the numerology of existing LTE/LTE-A but support a larger system bandwidth (e.g., 100 MHz). Or, one cell may support multiple numerologies. That is, terminals operating with different numerologies may coexist in one cell.

A numerology corresponds to one subcarrier spacing in the frequency domain. Different numerologies can be defined by scaling the reference subcarrier spacing by an integer N.

Figure 1 illustrates the structure of a wireless communication system to which the present disclosure can be applied.

Referring to Fig. 1, the NG-RAN consists of gNBs providing NG-RA (NG-Radio Access) user plane (i.e., new AS (access stratum) sublayer/PDCP (packet data convergence protocol)/RLC (radio link control)/MAC/PHY) and control plane (RRC) protocol termination for UE. The gNBs are interconnected via Xn interface. The gNBs are also connected to NGC (New Generation Core) via NG interface. More specifically, the gNBs are connected to AMF (Access and Mobility Management Function) via N2 interface and to UPF (User Plane Function) via N3 interface.

FIG. 2 illustrates a frame structure in a wireless communication system to which the present disclosure can be applied.

Next-generation RAT systems can support multiple numerologies, where the numerologies can be defined by subcarrier spacing and cyclic prefix (CP) overhead. Here, multiple subcarrier spacings can be derived by scaling the base (reference) subcarrier spacing by an integer N (or μ). Furthermore, even if it is assumed that very low subcarrier spacing is not used at very high carrier frequencies, the numerologies used can be selected independently of the frequency band. Furthermore, the next-generation RAT system can support various frame structures according to multiple numerologies.

Below, we examine OFDM numerologies and frame structures that can be considered in the next-generation RAT system. A number of OFDM numerologies supported in the next-generation RAT system can be defined as shown in Table 1 below.

μ Δf=2 ^μ ·15 [kHz] CP 0 15 Normal 1 30 common 2 60 General, Extended 3 120 common 4 240 common

Next-generation RAT systems support multiple numerologies (or subcarrier spacings (SCS)) to support various 5G/6G services. For example, when the SCS is 15 kHz, it supports wide area in traditional cellular bands; when the SCS is 30 kHz/60 kHz, it supports dense-urban, lower latency, and wider carrier bandwidth; and when the SCS is 60 kHz or higher, it supports bandwidth larger than 24.25 GHz to overcome phase noise. Although not described in Table 1, 6G systems may additionally support SCS of 480 kHz/960 kHz.

The frequency band of the next-generation RAT system is defined by various types of frequency ranges (e.g., FR1, FR2, etc.). For example, FR1 and FR2 can be configured as shown in Table 2 below. In addition, FR2 can mean millimeter wave (mmW).

Frequency Range designation Corresponding frequency range Subcarrier Spacing FR1 410MHz - 7125MHz 15, 30, 60kHz FR2 24250MHz - 52600MHz 60, 120, 240kHz

With respect to the frame structure in the next-generation RAT system, the sizes of various fields in the time domain are expressed in multiples of a time unit of T _c = 1/(Δf _max ·N _f ). Here, Δf _max = 480 · 10 ³ Hz and N _f = 4096. Downlink and uplink transmissions are organized into radio frames having a duration of T _f = 1/(Δf _max N _f /100) · T _c = 10 ms. Here, the radio frame is composed of 10 subframes, each having a duration of T _sf = (Δf _max N _f /1000) · T _c = 1 ms. In this case, there can be one set of frames for uplink and one set of frames for downlink.

In addition, transmission in uplink frame number i from a terminal must start before the start of the corresponding downlink frame at the terminal T _TA =(N _TA +N _TA,offset )T _c . For a subcarrier spacing configuration μ , slots are numbered in increasing order of n _s ^μ ∈{0,..., N _slot ^subframe,μ -1} within a subframe, and in increasing order of n _s,f ^μ ∈{0,..., N _slot ^frame,μ -1} within a radio frame. One slot consists of consecutive OFDM symbols of N _symb ^slot , where N _symb ^slot is determined according to a CP. The start of slot n _s ^μ in a subframe is temporally aligned with the start of OFDM symbol n _s ^μ N _symb ^slot in the same subframe. Not all terminals can transmit and receive simultaneously, which means that not all OFDM symbols in a downlink slot or uplink slot can be utilized.

Table 3 shows the number of OFDM symbols per slot (N _symb ^slot ), the number of slots per radio frame (N _slot ^frame,μ ), and the number of slots per subframe (N _slot ^subframe,μ ) in the general CP, and Table 4 shows the number of OFDM symbols per slot, the number of slots per radio frame, and the number of slots per subframe in the extended CP.

μ N _symb ^slot N _slot ^frame,μ N _slot ^subframe,μ 0 14 10 1 1 14 20 2 2 14 40 4 3 14 80 8 4 14 160 16

μ N _symb ^slot N _slot ^frame,μ N _slot ^subframe,μ 2 12 40 4

Fig. 2 is an example when μ=2 (SCS is 60 kHz), and referring to Table 3, 1 subframe can include 4 slots. 1 subframe={1,2,4} slot illustrated in Fig. 2 is an example, and the number of slot(s) that can be included in 1 subframe is defined as in Table 3 or Table 4. In addition, a mini-slot can include 2, 4, or 7 symbols, or more or less symbols.

With respect to physical resources in the next-generation RAT system, antenna ports, resource grids, resource elements, resource blocks, carrier parts, etc. may be considered. Hereinafter, the physical resources that may be considered in the next-generation RAT system will be examined in detail.

First, with respect to antenna ports, an antenna port is defined such that a channel through which a symbol on an antenna port is carried can be inferred from a 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 a large-scale property of a channel through which a symbol on one antenna port is carried can be inferred from a channel through which a symbol on another antenna port is carried. Here, the large-scale property includes one or more of delay spread, Doppler spread, frequency shift, average received power, and received timing.

FIG. 3 illustrates a resource grid in a wireless communication system to which the present disclosure can be applied.

Referring to FIG. 3, a resource grid is exemplarily described as consisting of N _RB ^μ N _sc ^RB subcarriers in the frequency domain and one subframe consisting of 14·2 ^μ OFDM symbols, but is not limited thereto. In the next generation RAT system, a transmitted signal is described by one or more resource grids consisting of N _RB ^μ N _sc ^RB subcarriers and OFDM symbols of 2 ^μ N _symb ^(μ) . Here, N _RB ^μ ≤ N _RB ^max,μ . The N _RB ^max,μ represents a maximum transmission bandwidth, which may vary not only between numerologies but also between uplink and downlink. In this case, one resource grid may be configured for μ and each antenna port p. Each element of the resource grid for μ and each antenna port p is referred to as a resource element and is uniquely identified by an index pair (k,l'). Here, k=0,...,N _RB ^μ N _sc ^RB -1 is an index on the frequency domain, and l'=0,...,2 ^μ N _symb ^(μ) -1 designates the position of a symbol within a subframe. When designating a resource element in a slot, an index pair (k,l) is used. Here, l=0,...,N _symb ^μ -1. The resource element (k,l') for μ and antenna port p corresponds to a complex value a _k,l' ^(p,μ) . If there is no risk of confusion or if a particular antenna port or numerology is not specified, the indices p and μ can be dropped, resulting in a complex value a _k,l' ^(p) or a _k,l' . Furthermore, a resource block (RB) is defined as N _sc ^RB =12 consecutive subcarriers on the frequency domain.

Point A serves as a common reference point of the resource block grid and is obtained as follows.

- offsetToPointA for Primary Cell (PCell) downlink represents the frequency offset between point A and the lowest subcarrier of the lowest resource block overlapping with the SS/PBCH block used by the UE for initial cell selection. It is expressed in resource block units assuming 15 kHz subcarrier spacing for FR1 and 60 kHz subcarrier spacing for FR2.

- absoluteFrequencyPointA represents the frequency-position of point A expressed as ARFCN (absolute radio-frequency channel number).

Common resource blocks are numbered from 0 upward in the frequency domain for the subcarrier spacing setting μ. The center of subcarrier 0 of common resource block 0 for the subcarrier spacing setting μ coincides with 'point A'. The relationship between common resource block number n _CRB ^μ in the frequency domain and resource elements (k, l) for the subcarrier spacing setting μ is given by the following mathematical expression 1.

In Equation 1, k is defined relative to point A such that k = 0 corresponds to the subcarrier centered at point A. The physical resource blocks are numbered from 0 to N _BWP,i ^size,μ -1 within a bandwidth part (BWP), where i is the number of the BWP. The relationship between a physical resource block n _PRB and a common resource block n _CRB in a BWP i is given by Equation 2 below.

N _BWP,i ^start,μ is the common resource block where the BWP starts relative to common resource block 0.

FIG. 4 illustrates a physical resource block in a wireless communication system to which the present disclosure can be applied. FIG. 5 illustrates a slot structure in a wireless communication system to which the present disclosure can be applied.

Referring to FIGS. 4 and 5, a slot includes multiple symbols in the time domain. For example, in the case of normal CP, one slot includes 7 symbols, but in the case of extended CP, one slot includes 6 symbols.

A carrier includes multiple subcarriers in the frequency domain. An RB (Resource Block) is defined as multiple (e.g., 12) consecutive subcarriers in the frequency domain. A BWP (Bandwidth Part) is defined as multiple consecutive (physical) resource blocks in the frequency domain, and can correspond to one numerology (e.g., SCS, CP length, etc.). A carrier can include up to N (e.g., 5) BWPs. Data communication is performed through activated BWPs, and only one BWP can be activated for one terminal. Each element in the resource grid is referred to as a Resource Element (RE), and one complex symbol can be mapped.

The next-generation RAT system can support up to 400 MHz per component carrier (CC). If a terminal operating in such a wideband CC always operates with the radio frequency (RF) chip for the entire CC turned on, the terminal battery consumption may increase. Or, when considering multiple use cases (e.g., eMBB, URLLC, Mmtc, V2X, etc.) operating in a single wideband CC, different numerologies (e.g., subcarrier spacing, etc.) may be supported for each frequency band within the CC. Or, the capability for maximum bandwidth may be different for each terminal. Considering this, the base station may instruct the terminal to operate in only a part of the bandwidth, not the entire bandwidth of the wideband CC, and the part of the bandwidth is conveniently defined as the bandwidth part (BWP). A BWP can be composed of consecutive RBs on the frequency axis and can correspond to one numerology (e.g., subcarrier spacing, CP length, slot/mini-slot interval).

Meanwhile, the base station can set multiple BWPs even within one CC set for the terminal. For example, in the PDCCH monitoring slot, a BWP that occupies a relatively small frequency domain can be set, and the PDSCH indicated by the PDCCH can be scheduled on a larger BWP.

Alternatively, when UEs are concentrated in a specific BWP, some terminals can be set to a different BWP for load balancing. Alternatively, considering frequency domain inter-cell interference cancellation between neighboring cells, some spectrum in the middle of the entire bandwidth can be excluded and both BWPs can be set within the same slot. That is, the base station can set at least one DL/UL BWP for a terminal associated with a wideband CC.

The base station can activate (by L1 signaling or MAC CE (Control Element) or RRC signaling, etc.) at least one DL/UL BWP among the DL/UL BWP(s) configured at a specific point in time. In addition, the base station can instruct switching to another configured DL/UL BWP (by L1 signaling or MAC CE or RRC signaling, etc.). Or, switching to a determined DL/UL BWP may be performed when a timer value expires based on a timer. In this case, the activated DL/UL BWP is defined as an active DL/UL BWP. However, since the UE may not receive the configuration for the DL/UL BWP when the UE is performing an initial access procedure or before the RRC connection is set up, the DL/UL BWP assumed by the UE in such a situation is defined as an initially active DL/UL BWP.

FIG. 6 illustrates physical channels used in a wireless communication system to which the present disclosure can be applied and a general signal transmission and reception method using the same.

In a wireless communication system, a terminal receives information from a base station through a downlink, and the terminal transmits information to the base station through an uplink. The information transmitted and received by the base station and the terminal includes data and various control information, and various physical channels exist depending on the type/purpose of the information they transmit and receive.

The second node of Fig. 6 can support DSS (dynamic spectrum sharing) 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. 6 can implement 6G technology or pre-6G wireless communication technologies (e.g., 5G, 4G). In addition, the first node and/or the second node can support full duplex mode as well as non-overlapping full duplex mode.

In Fig. 6, 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 (110) and the base station (120) and operations performed prior thereto are illustrated. However, the operations of Fig. 6 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. 6 illustrates direct wireless signal transmission and reception operations between the terminal (110) and the base station (120), one or more intermediate points may exist between the terminal (110) and the base station (120), and wireless signals may be transmitted and received via one or more intermediate points.

Referring to FIG. 6, in step 101, the terminal (110) and the base station (120) perform synchronization. For example, the terminal (110) performs an initial cell search operation. Specifically, the terminal (110) can detect a synchronization signal for at least one base station connection transmitted from the base station (120) according to a predefined rule. Here, the synchronization signal can include a plurality of synchronization signals classified according to a 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 (110) 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 (120) and obtain information (e.g., a cell identifier) about the base station (120).

In step 103, the terminal (110) obtains system information transmitted from the base station (120). The system information is information related to the properties, characteristics, and/or capabilities of the base station (120) required to access the base station (120) and use the service, and may be classified by content (e.g., whether it is essential for access), transmission structure (e.g., the channel used, whether it is provided on-demand), etc., and may be classified, for example, into first system information (e.g., MIB (master information block), primary system information), second system information (e.g., SIB (system information block), secondary system information), etc. If necessary, the terminal (110) may transmit a signal requesting system information before receiving the system information. However, the request and provision of the system information may be performed after the random access procedure described below.

In step 105, the terminal (110) and the base station (120) perform a random access procedure. The terminal (110) may transmit and/or receive at least one message (e.g., a random access preamble, a RAR (random access response) message, etc.) for the random access procedure based on information related to a channel for the random access procedure of the base station (120) obtained through system information (e.g., a channel location, a channel structure, a structure of a supported preamble, etc.). For example, the terminal (110) may transmit a first message (e.g., a preamble, MSG1) through the channel for the random access procedure, receive a second message (e.g., a RAR message, MSG2), transmit a third message (e.g., MSG3) including information related to the terminal (110) (e.g., identification information) to the base station (120) using scheduling information included in the second message, and receive a fourth message (e.g., MSG4) for contention resolution and/or connection establishment. As another example, the first message and the third message may be sent and received as one message, or the second message and the fourth message may be sent and received as one message.

In step 107, the terminal (110) and the base station (120) 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., an RRC (radio resource control) layer), a layer that handles mapping between logical channels and transport channels (e.g., a MAC (media access control) layer), and a layer that handles physical channels (e.g., a PHY (physical) layer). For example, the terminal (110) and the base station (120) may perform at least one of signaling for establishing a connection, signaling for determining settings related to communication, and signaling for indicating allocated resources.

In step 109, the terminal (110) and the base station (120) transmit and/or receive data. In other words, the terminal (110) and the base station (120) can process, transmit and/or receive data based on signaling of the control information. For example, when transmitting data, the terminal (110) or the base station (120) can perform at least one of channel encoding, rate matching, scrambling, constellation mapping, layer mapping, waveform modulation, antenna mapping, and resource mapping on the information bits. Conversely, when receiving data, the terminal (110) or the base station (120) can perform at least one of signal extraction from resources, waveform demodulation for each antenna, signal arrangement considering layer mapping, constellation demapping, descrambling, and channel decoding.

Table 5 shows an example of DCI format in the next-generation RAT system.

DCI format conjugation 0_0 Scheduling of PUSCH within a cell 0_1 Scheduling of one or multiple PUSCHs within a cell, or indicating cell group (CG) downlink feedback information to the UE. 0_2 Scheduling of PUSCH within a cell 1_0 Scheduling of PDSCH within a DL cell 1_1 Scheduling of PDSCH within a cell 1_2 Scheduling of PDSCH within a cell

Referring to Table 5, DCI formats 0_0, 0_1, and 0_2 may include resource information related to scheduling of PUSCH (e.g., UL/SUL (Supplementary UL), frequency resource allocation, time resource allocation, frequency hopping, etc.), transport block (TB) related information (e.g., MCS (Modulation Coding and Scheme), NDI (New Data Indicator), RV (Redundancy Version), etc.), HARQ (Hybrid - Automatic Repeat and request) related information (e.g., process number, DAI (Downlink Assignment Index), PDSCH-HARQ feedback timing, etc.), multi-antenna related information (e.g., DMRS sequence initialization information, antenna ports, CSI requests, etc.), power control information (e.g., PUSCH power control, etc.), and the control information included in each DCI format may be predefined. DCI format 0_0 is used for scheduling of PUSCH in one cell. Information included in DCI format 0_0 is transmitted with CRC (cyclic redundancy check) scrambled by C-RNTI (cell radio network temporary identifier, Cell RNTI) or CS-RNTI (Configured Scheduling RNTI) or MCS-C-RNTI (Modulation Coding Scheme Cell RNTI). DCI format 0_1 is used to indicate scheduling of one or more PUSCHs in a cell, or configure grant (CG) downlink feedback information to a UE. Information included in DCI format 0_1 is transmitted with CRC scrambled by C-RNTI or CS-RNTI or SP-CSI-RNTI (Semi-Persistent CSI RNTI) or MCS-C-RNTI. DCI format 0_2 is used for scheduling of PUSCH in a cell. Information included in DCI format 0_2 is transmitted CRC scrambled by C-RNTI or CS-RNTI or SP-CSI-RNTI or MCS-C-RNTI.

Next, DCI formats 1_0, 1_1, and 1_2 may include resource information related to scheduling of PDSCH (e.g., frequency resource allocation, time resource allocation, virtual resource block (VRB)-physical resource block (PRB) mapping, etc.), transport block (TB) related information (e.g., MCS, NDI, RV, etc.), HARQ related information (e.g., process number, DAI, PDSCH-HARQ feedback timing, etc.), multi-antenna related information (e.g., antenna port, transmission configuration indicator (TCI), sounding reference signal (SRS) request, etc.), PUCCH related information (e.g., PUCCH power control, PUCCH resource indicator, etc.), and control information included in each DCI format may be predefined.

DCI format 1_0 is used for scheduling PDSCH in one DL cell. Information included in DCI format 1_0 is transmitted CRC scrambled by C-RNTI or CS-RNTI or MCS-C-RNTI.

DCI format 1_1 is used for scheduling PDSCH in one cell. Information included in DCI format 1_1 is transmitted by CRC scrambled by C-RNTI or CS-RNTI or MCS-C-RNTI.

DCI format 1_2 is used for scheduling PDSCH in a cell. Information included in DCI format 1_2 is transmitted by CRC scrambled by C-RNTI or CS-RNTI or MCS-C-RNTI.

Quasi-Co Location (QCL)

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.

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 means a spatial (reception) channel characteristic parameter such as angle of arrival.

The UE may be configured with a list of up to M TCI-State settings in the upper layer parameter PDSCH-Config to decode 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.

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.

Quasi co-location relation is set by upper-layer parameters qcl-Type1 for the first DL RS and qcl-Type2 for the second DL RS (if set). 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.

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

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

- 'QCL-TypeB': {Doppler shift, Doppler spread}

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

- 'QCL-TypeD': {Spatial Rx parameter}

For example, if a target antenna port is a specific NZP CSI-RS, the corresponding NZP CSI-RS antenna port(s) 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 instructed/configured can receive the corresponding NZP CSI-RS using the Doppler and delay values measured at the QCL-TypeA TRS, and apply the receive beam used for QCL-TypeD SSB reception to the corresponding NZP CSI-RS reception.

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

CSI framework

In relation to setting and reporting of channel state information (CSI), at least one of the following CSI frameworks may be applied:

(CSI Framework Method 1) Multiple CSI-RS resource sets are linked for one CMR (channel measurement resource) (e.g., resources configurable by the resourcesForChannelMeasurement parameter) or one IMR (interference measurement resource) (e.g., resources configurable by the csi-IM-ResourcesForInterference parameter or the nzp-CSI-RS-ResourcesForInterference parameter) within a CSI reporting configuration (e.g., CSI-ReportConfig). For example, CSI-RS resource set #1 and CSI-RS resource set #2 are linked for CMR, and CSI-RS resources belonging to CSI-RS resource set #1 can be configured with 16 antenna ports (APs), and CSI-RS resources belonging to CSI-RS resource set 2 can be configured with 8 antenna ports (APs).

(CSI Framework Method 2) When there is one CSI-RS resource set linked to one CMR or one IMR in the CSI reporting configuration, the CSI-RS resource set is configured with one or more CSI-RS resources having different properties such as the number of APs and/or power offset. For example, for CSI-RS resource set #1 configured as CMR, CSI-RS resource #1 belonging to CSI-RS resource set #1 may be configured with 16 antenna ports (APs) (or power offset #1 value may be set), and CSI-RS resource #2 belonging to the same CSI resource set may be configured with 8 antenna ports (APs) (or power offset #2 value may be set).

(CSI Framework Method 3) When there is a CSI-RS resource set linked to a CMR or an IMR in the CSI reporting configuration, some or all of the CSI-RS resource(s) in the CSI-RS resource set can be configured with multiple AP numbers and/or power offsets, etc. For example, for the CSI-RS resource set #1 configured with CMR, the CSI-RS resource #1 belonging to the CSI-RS resource set #1 can be configured with a maximum of 16 antenna ports (APs) and CSI reporting utilizing some of the AP(s) can be configured, or the CSI-RS resource #2 belonging to the same CSI-RS resource set can be configured with multiple power offset values and CSI reporting utilizing all or part of the power offsets can be configured.

Under the CSI framework described above, the CSI reporting method can be defined through at least one of the following options.

(Option 1) CSIs considering multiple AP counts and/or multiple power offset values set in a single CSI report may all be included in a single CSI report. Alternatively, CSIs considering multiple AP counts and/or multiple power offsets may be included in a single CSI report through configuration/instruction of the base station (in this case, the AP counts and/or power offsets set/instructed by the base station may be part of the AP counts and/or power offset values set in the corresponding CSI report).

(Option 2) Even if multiple AP counts and/or multiple power offset values are set in a single CSI report, CSIs considering a single AP count and/or a single power offset can be included in a single CSI report through the configuration/instruction of the base station.

(Option 3) Even if multiple AP counts and/or multiple power offset values are set in a single CSI report, CSIs considering some AP counts and/or some power offsets may be included in a single CSI report through the terminal’s judgment/decision (using criteria set in advance by the base station or pre-defined).

There can be L(>1) sub-configurations configured within a CSI report configuration (CSI-ReportConfig), and each sub-configuration can correspond to one spatial or power domain adaptation pattern.

Here, the spatial domain adaptation pattern may correspond to a specific number of antenna ports (or antenna port on/off pattern), or may correspond to a specific CSI-RS power value (e.g., a CSI-RS power value determined by the powerControlOffsetSS parameter, which is a power offset value between SSS and CSI-RS, because when some antenna elements corresponding to one antenna port are turned off, it may affect the CSI-RS power value).

If the method of CSI Framework Method 2 is applied, when the number of A1 APs (or P1 power value) is set for CSI-RS index #n1 belonging to a resource set and the number of A2 APs (or P2 power value) is set for CSI-RS index #n2 belonging to the same resource set, the sub-configuration index #s1 is set to be linked with CSI-RS index #n1 and the sub-configuration index #s2 is set to be linked with CSI-RS index #n2, thereby allowing different spatial domain adaptation patterns to be set for each sub-configuration. If the method of the CSI framework method 3 is applied, 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 value or delta1 from the P1 power value) is linked to the sub-configuration index #s1, and the number of A2 APs (or P2 power value or delta2 from the P1 power value) which is less than the A1 constituting the CSI-RS index #n1 is linked to the sub-configuration index #s2, thereby allowing different spatial domain adaptation patterns to be set for each sub-configuration.

Additionally, 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 the PDSCH and the CSI-RS, the powerControlOffsetSS parameter, which is the power offset value between the SSS and the CSI-RS, etc.) is varied.

If the method of CSI Framework Method 2 is applied, when CSI-RS index #n1 belonging to a resource set is set to a P1 power value and CSI-RS index #n2 belonging to the same resource set is set to a P2 power value, the sub-configuration index #s1 is set to be linked with CSI-RS index #n1 and the sub-configuration index #s2 is set to be linked with CSI-RS index #n2, so that the power domain adaptation pattern can be set differently for each sub-configuration.

If the method of the CSI framework method 3 is applied, when the P1 power value (and the P2 power value) are set for the CSI-RS index #n1 belonging to the resource set, the P1 power value is linked to the sub-configuration index #s1 and the P2 power value (or the delta from the P1 power value) is linked to the sub-configuration index #s2, thereby allowing different power domain adaptation patterns to be set for each sub-configuration. A CSI report composed of CSIs corresponding to N (N value greater than or equal to L and less than or equal to 1) sub-configurations among the L sub-configurations (by utilizing one of the methods of Option 1, Option 2, and Option 3 described above) can be fed back to the base station.

As described above, one or more sub-settings may be set within one CSI reporting setting, and within each sub-setting, one or a combination of the following settings may be set.

- List of IDs of one or more CSI-RS resource(s).

- Antenna port subset indication consisting of a bitmap

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

For the convenience of explanation, a CSI reporting configuration that includes a sub-configuration in which an ID list of one or more CSI-RS resource(s) is set is referred to as type 2 SD (spatial domain) adaptation. A CSI reporting configuration that includes a sub-configuration in which an antenna port subset indication configured as a bitmap is set is referred to as type 1 SD adaptation. A CSI reporting configuration that includes a sub-configuration in which an additional power offset delta value is set is referred to as PD (power domain) adaptation. One or more ID lists of CSI-RS resource(s) and/or power offset delta values may be set for sub-configuration(s) belonging to a CSI reporting configuration, in which case it is referred to as type 2 SD+PD adaptation. An antenna port subset indication and/or power offset delta values configured as a bitmap may be set for sub-configuration(s) belonging to a CSI reporting configuration, in which case it is referred to as type 1 SD+PD adaptation.

For type 1 SD or PD or type 1 SD+PD adaptation, each CSI-RS resource can be associated with all sub-configurations configured in one CSI reporting configuration, respectively, and for type 2 SD, each CSI-RS resource can be associated with only a single sub-configuration among multiple sub-configurations in one CSI reporting configuration. For type 2 SD+PD adaptation, the list #1 of CSI-RS resource(s) configured in a sub-configuration in the same CSI reporting configuration and the list #2 of CSI-RS resource(s) configured in another sub-configuration can be identical to or disjoint from each other.

Meanwhile, when L sub-configurations are configured in one CSI reporting configuration, the UE can report CSI information corresponding to each of the L sub-configurations to the base station via one PUSCH/PUCCH. Among the L sub-configurations, only N (N value greater than or equal to 1 and less than or equal to L) sub-configurations(s) can be activated or triggered via MAC-CE or DCI, in which case the UE can report CSI information corresponding to each of the N sub-configurations to the base station via one PUSCH/PUCCH. Specifically, for a CSI reporting configuration in which semi-persistent CSI reporting on PUCCH is configured, N sub-configurations(s) among the L sub-configurations configured via MAC-CE can be activated, and for a CSI reporting configuration in which semi-persistent CSI reporting on PUSCH or aperiodic CSI reporting is configured, N sub-configurations(s) among the L sub-configurations configured via DCI can be triggered.

Network energy saving (NES)

Energy saving of base stations is considered important in wireless communication systems because it can contribute to building eco-friendly networks by reducing carbon emissions and reducing operational expenditure (OPEX) for telecommunications industry players. In particular, as the introduction of next-generation wireless communication requires higher transmission rates, base stations must be equipped with more antennas and provide services through wider bandwidths and frequency bands.

Because of this, the energy cost of the base station increases excessively, so the base station needs to apply energy-saving methods.

A base station may operate technologies such as controlling on/off for a certain duration in the time axis for NES purposes, controlling transmission/reception resources for UE-common or UE-specific signals/channels, changing the amount of frequency domain resources, controlling transmission power, or turning antenna ports and/or TRPs on/off in the spatial domain. A state in which such technologies (defined/referred to as NES_tech for convenience of explanation) are applied may be defined/referred to as an NES mode or NES state.

The base station may inform the terminal of which NES technology(s) are applied for each NES technology (or corresponding group) (Method 1), or may pre-set the corresponding NES technology(s) (or corresponding group)(s) by code-point of a specific indicator (for example, the indicator may be indicated by DCI or MAC CE, or may be an indicator set by upper layer signaling) (Method 2).

For example, in case of method 1, if at least one NES_technology is applied, the terminal can define the state as the NES mode or NES state, or it can be referred to as a different NES mode or a different NES state depending on which NES_technology is applied. In contrast, in case of method 2, for example, when there is a 1-bit indicator, when '0' does not have a corresponding NES_technology and '1' corresponds to one or more NES_technology linkages, the terminal can define the state as the NES mode or NES state when it receives '1' from the indicator. As another example, when there is a 2-bit indicator, if '00' has no corresponding NES_technology, '01' has one or more NES_technology_As associated, '10' has one or more NES_technology_Bs associated, and '11' has one or more NES_technology_Cs associated, the terminal can define the state as NES mode or NES state when it receives a code-point other than '00' from the indicator. On the other hand, if the terminal is directed to '01', it is defined as NES state #1, if it is directed to '10', it is defined as NES state #2, and if it is directed to '11', it can be defined as NES state #3. Based on this, it can be distinguished whether it is a NES state or not or which NES state it is for each code-point.

A base station can turn on or off certain spatial elements or adjust power values for downlink signals/channels for NES purposes. In the present disclosure, spatial elements may mean antenna ports, active transceiver chains, panels, or TRPs. In order to dynamically apply various NES techniques in spatial domain and power domain, the base station can link CSI-RS resources (sets) having different antenna ports for a single CSI reporting setting (e.g., CSI-ReportConfig), or 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.) can be linked.

Operation and measurement method for on-demand SSB (synchronization signal block)

From the perspective of a base station operating multiple frequency bands, even when the number of terminals served is small or the traffic load is relatively low, the amount of energy consumed by periodically transmitting SSB and/or system information can be large.

In the description of the present disclosure, the frequency band may be replaced with a band, a carrier, a serving cell, or a BWP.

FIG. 7 illustrates an SSB transmission method of a base station operating multiple frequency bands that can be applied to the present disclosure.

Referring to FIG. 7, a base station operating three frequency bands may periodically transmit (legacy) SSB only on some frequency bands (e.g., F1 in FIG. 7). On the other hand, the base station may transmit simplified (or modified) SSB (S-SSB) on the remaining frequency bands (e.g., F2 in FIG. 7) or may not transmit SSB on other frequency bands (e.g., F3 in FIG. 7). Through this, the base station can achieve energy conservation.

In this regard, for a terminal operating in F2 or F3, it can request SSB transmission from a base station in the corresponding frequency band. The SSB transmitted based on this may be referred to as on-demand SSB. The on-demand SSB may be (legacy) SSB or may be S-SSB.

The frequency band in which the base station periodically transmits SSB may correspond to a non-NES frequency band, and other frequency bands may correspond to NES frequency bands. For convenience of explanation, a cell in which SSB may not be transmitted, such as F2 or F3 (e.g., the above-mentioned NES frequency band), may be referred to as an SSB-less cell. For example, from the perspective of a terminal, an SSB-less cell may be a PCell, a PSCell, or an SCell.

The present disclosure specifically proposes operation of on-demand SSB in an SSB-less cell and (configuration) information related thereto, and methods for performing measurements for on-demand SSB.

In relation to the method proposed in the present disclosure, the operation of a terminal in a (RRC) connected mode/state (hereinafter, CONNECTED terminal) and the operation of a terminal in an idle or inactive mode/state (hereinafter, IDLE/INACTIVE terminal) can be considered.

For example, with respect to the method related to on-demand SSB in an SSB-less cell described in the present disclosure, a CONNECTED terminal may be based on a CA (carrier aggregation) operation (e.g., a CA operation supported in 5G/6G based wireless communication systems, etc.). In this case, the SSB-less cell may correspond to a PCell, a PSCell, or a SCell for the CA operation. In addition, an IDLE/INACTIVE terminal may be based on a NES operation (e.g., a NES operation supported in 5G/6G based wireless communication systems, etc.). In this case, the SSB-less cell may correspond to a cell to which the NES operation is applied (e.g., a NES cell). Alternatively, the on-demand SSB may be operated in a cell to which the NES operation is not applied (e.g., a non-NES cell).

In relation to the proposed method in the present disclosure, an IDLE/INACTIVE terminal can (re)select a cell to determine a first cell as a serving cell and obtain system information from the first cell. In addition, a CONNECTED terminal can obtain system information from the first cell or obtain system information by receiving a DCI, MAC-CE, or terminal-only message transmitted by a base station.

At this time, the terminal can confirm that the second cell/TRP supports and/or operates the SSB-less cell/TRP operation and/or the on-demand SSB operation through the acquired system information (e.g., MIB, SIB1, or other SIB) of the first cell or the DCI/MAC-CE/terminal-only message. For this purpose, information (e.g., an indicator) indicating that the second cell/TRP supports the SSB-less cell/TRP operation and/or the on-demand SSB operation may be included in the system information or the DCI/MAC-CE/terminal-only message of the first cell. Additionally or alternatively, UL resource (e.g., PRACH resource/preamble, etc.) setting for requesting on-demand SSB for the second cell/TRP may be included. Additionally or alternatively, a reference signal (RS) setting mapped to the second cell/TRP or a reference signal (RS) setting mapped to a specific on-demand SSB of the second cell/TRP or a reference signal (RS) setting in a quasi-co-location (QCL) relationship may be included.

With respect to the proposed method in the present disclosure, a reference signal (RS) may be a reference signal (RS) for a first cell/TRP or a second cell/TRP, and may be a reference signal (RS) mapped to a specific SSB (or a specific SSB index) of the first cell/TRP or the second cell/TRP. A plurality of reference signals (RS) may be configured as a single reference signal (RS) set, and each reference signal (RS) in the set may be indicated by a different reference signal (RS) index. Different reference signal (RS) indices may be mapped to or connected in a QCL relationship to different SSB indices of the first cell/TRP or the second cell/TRP.

When a reference signal (RS) for the second cell/TRP is set, a terminal supporting NES can perform layer 1 or layer 3-based measurement targeting the reference signal (RS). At this time, the reference signal (RS) can be an SSB, CSI-RS, or a separate new reference signal (RS) of the first cell/TRP or the second cell/TRP.

In this regard, the terminal may trigger the above-described measurement when one or more of the following conditions are satisfied.

- Condition 1. If the terminal supports SSB-less cell/TRP operation and/or on-demand SSB operation for NES.

- Condition 2. If a message (e.g. RRC release message) indicating a transition from CONNECTED mode to IDLE/INACTIVE mode sets/instructs the above-mentioned measurement.

- Condition 3. If the system information acquired by the terminal from the serving cell sets/instructs the above-mentioned measurement.

- Condition 4. If the SSB (or CSI-RS) measurement value for the first cell/TRP is below the threshold value.

- Condition 5. If the frequency priority for the 2nd cell/TRP is higher than the frequency priority for the 1st cell/TRP.

- Condition 6. If the RACH process fails in the first cell/TRP

- Condition 7. If radio link failure or beam failure occurs in the first cell/TRP.

- Condition 8. When a command is received from the first cell/TRP instructing to perform measurements in the manner described above (for example, the command may be received via an RRC message, MAC-CE, or DCI).

The terminal performs an UL transmission (e.g., a PRACH transmission) requesting an on-demand SSB for the second cell/TRP according to UL resource configuration in the first cell/TRP or the second cell/TRP, and thereafter, the terminal can receive the requested on-demand SSB in the second cell/TRP. At this time, a specific UL resource (e.g., a specific PRACH resource/preamble) can be mapped to one or multiple specific on-demand SSB indices, and different UL resource(s) can be mapped to different on-demand SSB indices. In addition, a specific UL resource can be mapped to one, multiple, or all of MIB, SIB1, SIBx (wherein, x>1 is an integer), and on-demand SSB, and based on this, the terminal can be configured to request one, multiple, or all of them.

Alternatively, the terminal may trigger the RACH to request an on-demand SSB, and may request one, multiple, or all of the MIB, SIB1, SIBx (wherein x is an integer > 1), and on-demand SSB via RACH MSG3 or RACH MSGA. For example, the RACH MSG3 or RACH MSGA may transmit a UCI/MAC-CE/RRC message, and the UCI/MAC-CE/RRC message may include information (e.g., an indicator) requesting one, multiple, or all of the MIB, SIB1, SIBx (wherein x is an integer > 1), and on-demand SSB. For example, the UCI/MAC-CE/RRC message may include information (e.g., an indicator) requesting an on-demand SSB, or may include SSB index(es) corresponding to the SSB(s) to be requested. Additionally, the UCI/MAC-CE/RRC message may include information indicating MIB (e.g., an indicator), information indicating SIB1 (e.g., an indicator), and information indicating SIBx (wherein x is an integer > 1) (e.g., an indicator). The UCI/MAC-CE/RRC message may include bitmap information composed of bits for each of the corresponding pieces of information, and multiple bit strings may be composed by connecting each piece of information.

The IDLE/INACTIVE terminal described above can perform UL transmission requesting on-demand SSB if one or more of the following conditions are satisfied.

- Condition A. A condition where the measured value of the reference signal (RS) mapped to the second cell/TRP is higher than or equal to the offset value measured of the reference signal (RS) for the first cell/TRP (e.g., cell defining SSB).

- Condition B. The condition where the measured value of the reference signal (RS) mapped to the second cell/TRP is greater than or equal to the threshold value.

- Condition C. The condition where the measured value of the reference signal (RS) (e.g., cell defining SSB) for the first cell/TRP is below the threshold value.

- Condition D. The frequency of the reference signal (RS) mapped to the second cell/TRP or the frequency for the second cell/TRP has a higher priority than the frequency for the first cell/TRP.

- Condition E. The second cell/TRP and the first cell/TRP belong to the same PLMN or an equivalent PLMN.

- Condition F. A condition in which the second cell is determined to be a suitable cell for the terminal based on system information about the second cell/TRP obtained from the first cell/TRP.

In this regard, the IDLE/INACTIVE terminal can receive on-demand SSB and MIB, SIB1, and SIBx for the second cell, and perform cell reselection from the first cell to the second cell.

Additionally or alternatively, the IDLE/INACTIVE terminal may receive SIB1 to obtain RACH configuration for the first cell or the second cell, and perform a RACH process for the first cell or the second cell to switch to the CONNECTED mode. At this time, the PCell or PSCell of the terminal may be the first cell or the second cell. Thereafter, before or after switching to the CONNECTED mode, the terminal may configure the second cell (or the first cell) as an SCell in addition to the first cell (or the second cell), which is the PCell or the PSCell.

Additionally or alternatively, an IDLE/INACTIVE/CONNECTED terminal may request and receive all of the on-demand SSB, MIB, SIB1, SIBx via the aforementioned UL transmissions simultaneously, or may request and receive one or some of them. Alternatively, the terminal may request the on-demand SSB first, and then perform a separate UL transmission requesting MIB, SIB1, SIBx. Alternatively, the terminal may request the on-demand SSB and MIB first, and then perform a separate UL transmission requesting SIB1, SIBx.

Accordingly, the terminal may receive all of them together in a single request, or may sequentially request on-demand SSB and MIB, SIB1, and SIBx respectively, or may sequentially receive them, or may request and receive only some of them. For example, if the second cell is configured as a SCell, the terminal may request and receive only on-demand SSB, and, if necessary, may request and receive on-demand SSB and MIB simultaneously in a single UL transmission to receive the on-demand SSB and MIB. As another example, if the second cell is configured as a PSCell, the terminal may request and receive on-demand SSB and MIB simultaneously to receive the on-demand SSB and MIB. As another example, if the second cell is configured as a PCell, the terminal may request and receive on-demand SSB and MIB/SIB1 simultaneously or sequentially to receive the on-demand SSB and MIB/SIB1, and then request and receive SIBx according to on-demand SI (system information) settings of SIB1.

In the proposed method of the present disclosure, the first cell/TRP and the second cell/TRP may be the same or different. Additionally, the first TRP and the second TRP may belong to the same or different cells.

The embodiments described below are distinguished only for the sake of clarity of explanation, and a part/entire configuration of one embodiment may be applied in combination/combination with a part/entire configuration of another embodiment, or may be applied independently.

Example 1

This embodiment relates to a method for performing measurements through instructions for on-demand SSB.

The base station may set the SSB (or CSI-RS) for the second cell/TRP as a measurement object (e.g., L1 measurement object) while setting up measurement (e.g., L1 (layer 1) measurement) for the second cell/TRP via system information or terminal-only message. Alternatively, the base station may set the SSB (or CSI-RS) for the first cell/TRP or a reference signal (RS) described in the present disclosure as a measurement object (e.g., L1 measurement object) while setting up measurement (e.g., L1 (layer 1) measurement) for the second cell/TRP via system information or terminal-only message.

In this regard, the terminal may measure a measurement target (e.g., an L1 measurement target) according to the RRC settings of the base station, and periodically perform a measurement report (e.g., an L1 measurement report) of the second cell/TRP, or perform a measurement report (e.g., an L1 measurement report) of the second cell/TRP according to a specific event.

Additionally or alternatively, the base station may transmit DCI via the first cell/TRP, the second cell/TRP, or the third cell/TRP, and instruct the terminal to one of a plurality of measurement targets (e.g., L1 measurement targets) for the cell/TRP configured by RRC via the DCI. In addition, the DCI may instruct whether to start measurement for the instructed measurement target and/or whether to report a measurement result for the measurement target.

For example, one or more of the following measurement targets can be set as RRC as a measurement target for the second cell/TRP.

- Measurement target 1. SSB, CSI-RS, or reference signal (RS) for the first cell/TRP

- Measurement target 2. SSB, CSI-RS, or reference signal (RS) for the second cell/TRP

- Measurement target 3. SSB, CSI-RS, or reference signal (RS) for the 3rd cell/TRP

- Measurement target 4. Reference cell/TRP designation and SSB, CSI-RS, or reference signal (RS) for it

At this time, the first cell may be a PCell/PSCell, and the second cell and the third cell may be SCell. Alternatively, the second cell may be a PCell/PSCell, and the first cell and the third cell may be SCell. In addition, the first TRP, the second TRP, and the third TRP may be the same PCell/PSCell or SCell, or two or three of the first TRP, the second TRP, and the third TRP may belong to the same or different PCell/PSCell or SCell. For such measurements, the first cell/TRP or the third cell/TRP may be set as a reference cell/TRP for the second cell/TRP.

Additionally, when the first cell/TRP is a PCell/PSCell, the SSB (or CSI-RS) for the second cell/TRP can be an on-demand SSB (or on-demand CSI-RS).

Additionally, the DCI described above may include information indicating what is being measured and/or information indicating whether a measurement is to be reported.

For example, with respect to information indicating a measurement target, the DCI may include information about a cell of the measurement target (e.g., a first cell/TRP, a second cell/TRP, or a third cell/TRP). In addition, the DCI may include information indicating an SSB, a CSI-RS, or a reference signal (RS) for the cell/TRP of the measurement target. In addition, the DCI may include information about whether the indicated measurement target SSB is an on-demand SSB. For example, in the case of an on-demand SSB, the DCI may include information about whether a UL transmission requesting a separate on-demand SSB should be triggered. Alternatively, in the case of an on-demand SSB, the DCI may include information about whether an on-demand SSB is triggered and transmitted by the base station during a certain time interval after a certain time interval after receiving the DCI without a separate on-demand SSB request. In this regard, information about a time interval during which the on-demand SSB is transmitted after receiving the DCI may also be included. Additionally, the DCI may include information about measurement quantities (e.g., L1-RSRP, L1-RSRQ, L1-RSSI, etc.).

For example, with respect to information indicating whether to report a measurement, the DCI may include information about one-shot reporting, a designated event triggering the reporting, and/or event-triggered periodic reporting. In addition, the DCI may include information about PUCCH resource indicator or PRACH resource/preamble allocation for reporting. In addition, the DCI may include information about time interval/interval (e.g., number of slots, absolute time, etc.) of PUCCH transmission or PRACH transmission for DCI reception and reporting.

Based on the RRC configuration and/or DCI indication described above in the present disclosure, the UE may receive a measurement and/or report (e.g., L1 measurement and/or report) indication, start measurement for a measurement target indicated by the RRC configuration or DCI, and report a measurement result (e.g., L1 measurement result) via PUCCH indicated by the RRC configuration or DCI. For example, a first RRC message or a first DCI may configure/indicate whether to perform the measurement via SSB of a reference cell or via on-demand SSB on SCell. If on-demand SSB is indicated, the UE may trigger an UL transmission (e.g., RACH transmission) to request on-demand SSB, or perform measurement (e.g., L1 measurement) after determining that on-demand SSB is transmitted for a predetermined time or continuously after a predetermined time after RRC/DCI reception even without UL transmission.

Additionally, the first or second RRC message, or the first or second DCI, may indicate reporting of the measurement result. Based on this, the UE may report the measurement result through PUCCH transmission, or may trigger the RACH to report the measurement result (e.g., L1 measurement result) through MAC-CE or RRC message. Based on this, the second cell/TRP may be set as the serving cell of the UE or the PCell/PSCell.

Additionally, if a threshold is set via RRC, even without reporting, if the measurement result for the second cell/TRP is greater than or equal to the threshold, the second cell/TRP can be set/activated as a serving cell/TRP, or the second cell/TRP can be set/activated as a PCell/PSCell to perform a PCell/PSCell change.

The specific measurement method proposed in the present disclosure may be as follows.

If SSB (or CSI-RS) for the second cell/TRP is being transmitted, the terminal can measure the SSB (or CSI-RS) set/designated as a measurement target and report the measurement result to the base station.

Additionally or alternatively, if the SSB (or CSI-RS) for the second cell/TRP is available but is not being transmitted during the DTX inactive interval, the UE may measure the SSB (or CSI-RS) of the first cell/TRP or the third cell/TRP or the reference signal (RS) in the present disclosure (instead of the SSB (or CSI-RS) for the second cell/TRP set/designated as the measurement target) during the DTX inactive interval, and report the measurement result thereof to the base station.

Additionally or alternatively, if the SSB (or CSI-RS) for the second cell/TRP is not available and is not being transmitted based on being an on-demand SSB or SSB-less cell/TRP, the UE may measure the SSB (or CSI-RS) of the first cell/TRP or the third cell/TRP or the reference signal (RS) in the present disclosure (instead of the SSB (or CSI-RS) for the second cell/TRP set/designated as the measurement target), and report the measurement result thereof to the base station.

Additionally or alternatively, if the SSB (or CSI-RS) for the second cell/TRP is not available and not being transmitted based on whether it is an on-demand SSB or SSB-less cell/TRP, the UE may request on-demand SSB (or CSI-RS) for the second cell/TRP that is set/designated as a measurement target, and then measure the requested on-demand SSB (or CSI-RS) and report the measurement result thereof.

Additionally or alternatively, if the SSB (or CSI-RS) for the second cell/TRP is not available and is not being transmitted based on being an on-demand SSB or SSB-less cell/TRP, the UE may expect that the on-demand SSB (or CSI-RS) will be transmitted during a certain time interval after the configuration/designation even if the UE does not (separately) request the on-demand SSB (or CSI-RS) for the second cell/TRP configured/designated as a measurement target. Accordingly, the UE may measure the on-demand SSB (or CSI-RS) and report the measurement result thereof.

For the above-described operations, the terminal can set a mapping relationship by beam index for the SSB (or CSI-RS) of the second cell/TRP and the SSB (or CSI-RS) of the first cell/TRP or the third cell/TRP. For example, the base station can set the SSB index #k of the first cell/TRP or the third cell/TRP to be mapped to the SSB index #m of the second cell/TRP with a QCL relationship, and can transmit the setting to the terminal through system information or a terminal-only message. Based on this, the terminal can replace the measurement value for the SSB index #k of the first cell/TRP or the third cell/TRP with the measurement value for the SSB index #m of the second cell/TRP and report it.

Additionally or alternatively, (if there is no separate mapping setting), the terminal may perform measurement and reporting (or select PRACH resource) assuming that the beam index-wise directions for the SSB (or CSI-RS) for the second cell/TRP and the SSB (or CSI-RS) of the first cell/TRP or the third cell/TRP are the same. For example, it may be assumed that the SSB index #k of the second cell/TRP and the SSB index #k of the first cell/TRP or the third cell/TRP have a QCL relationship with each other. Based on this, the terminal may replace the measurement value for the SSB index #k of the first cell/TRP or the third cell/TRP with the measurement value for the SSB index #k of the second cell/TRP and report it.

Additionally, the DCI described in the present embodiment can trigger a contention free RACH or a contention based RACH. For example, the DCI can trigger a contention free RACH to the second cell/TRP while indicating an (L1) measurement target and/or reporting for the second cell/TRP. If the (L1) measurement target for the second cell/TRP is an on-demand SSB as described above, the UE can request the on-demand SSB via the RACH triggered upon reception of the DCI. Alternatively, if the (L1) measurement target for the second cell/TRP is an on-demand SSB as described above, the UE can determine that the on-demand SSB is triggered and transmitted without a separate request upon reception of the DCI. In this regard, if the on-demand SSB is indicated via the DCI, the UE can measure the on-demand SSB for selecting the corresponding PRACH resource/preamble and transmit the PRACH based on the same. The specific operation for this can be based on Example 2, which will be described below.

Additionally, the DCI described in this embodiment may be CRC scrambled with the C-RNTI of the terminal, or CRC scrambled with the SI-RNTI, the P-RNTI, the NES-RNTI, or a separate group RNTI received by multiple terminals. Additionally or alternatively, the RACH described above may be triggered via a MAC-CE, a paging message, or a short message of the paging DCI instead of the DCI.

Example 2

This embodiment relates to a RACH method for cells/TRPs associated with on-demand SSB.

In connection with the method proposed in the present disclosure, the terminal can perform RACH for a cell/TRP, for example, a second cell/TRP, associated with on-demand SSB.

For example, the UE may perform RACH for reasons such as PDCCH order, UL time alignment, scheduling request (SR), or mobility. Alternatively, the UE may perform RACH to request on-demand SSB or system information for the second cell/TRP.

Additionally, if the beam failure instance indicator for the second cell/TRP is greater than or equal to the maximum value, the UE may report BSR MAC CE or PUCCH SR (for example, if the second cell/TRP is SCell), or trigger RACH (for example, if the second cell/TRP is PCell/PSCell). In this case, the BSR MAC CE, PUCCH SR, or RACH transmission for the second cell/TRP may be performed in the first cell/TRP, the second cell/TRP, or the third cell/TRP. In addition, for the BSR MAC CE transmission, the UE may perform PRACH resource transmission of the first cell/TRP, the second cell/TRP, or the third cell/TRP, and transmit the BSR MAC CE through the RACH MSG3 or MSGA message accordingly.

In this regard, the first cell may be a PCell/PSCell, and the second cell and the third cell may be SCells. Alternatively, the second cell may be a PCell/PSCell, and the first cell and the third cell may be SCells. In addition, the first TRP, the second TRP, and the third TRP may be the same PCell/PSCell or SCell, or two or three of the first TRP, the second TRP, and the third TRP may belong to the same or different PCell/PSCell or SCell. In addition, for the aforementioned RACH operation, the first cell/TRP or the third cell/TRP may be set as a reference cell/TRP for the second cell/TRP.

If RACH is performed with PRACH resources of the second cell/TRP based on reasons for the second cell/TRP as described above, the terminal can perform the following operations.

If an SSB (or CSI-RS) for a cell/TRP (e.g., a second cell/TRP) belonging to a PRACH resource is being transmitted, the terminal can measure the SSB (or CSI-RS) and select a PRACH resource based on this to perform transmission.

Additionally or alternatively, if the SSB (or CSI-RS) for a cell/TRP (e.g., the second cell/TRP) belonging to the PRACH resource is available but is not being transmitted during the DTX inactive interval, the UE may measure the SSB (or CSI-RS) of the first cell/TRP or the third cell/TRP or the reference signal (RS) in the present disclosure during the DTX inactive interval, and select a PRACH resource based on the measurement result to perform transmission.

Additionally or alternatively, if the SSB (or CSI-RS) for a cell/TRP (e.g., the second cell/TRP) belonging to the PRACH resource is not available and is not being transmitted based on whether it is an on-demand SSB or SSB-less cell/TRP, the UE may measure the SSB (or CSI-RS) of the first cell/TRP or the third cell/TRP or the reference signal (RS) in the present disclosure, and select a PRACH resource based on the same to perform transmission.

Additionally or alternatively, if the SSB (or CSI-RS) for a cell/TRP (e.g., the second cell/TRP) belonging to the PRACH resource is not available and is not being transmitted based on whether it is an on-demand SSB or an SSB-less cell/TRP, the UE may request an on-demand SSB (or CSI-RS) for the second cell/TRP (if the DCI triggering the RACH triggers an on-demand SSB request), and then measure the requested on-demand SSB (or CSI-RS) and select a PRACH resource based on the measured SSB.

Additionally or alternatively, if SSB (or CSI-RS) for a cell/TRP (e.g., the second cell/TRP) belonging to the PRACH resource is not available and not being transmitted based on whether it is an on-demand SSB or SSB-less cell/TRP (if the DCI triggering RACH triggers on-demand SSB without a separate on-demand SSB request), the UE may measure the on-demand SSB (or CSI-RS) for the second cell/TRP and select a PRACH resource based on the measurement result to perform transmission.

For the above-described operations, the terminal can set a mapping relationship by beam index for the SSB (or CSI-RS) of the second cell/TRP and the SSB (or CSI-RS) of the first cell/TRP or the third cell/TRP. For example, the base station can set the SSB index #k of the first cell/TRP or the third cell/TRP to be mapped to the SSB index #m of the second cell/TRP with a QCL relationship, and can transmit the setting to the terminal through system information or a terminal-only message. Based on this, if the measurement value for the SSB index #k of the first cell/TRP or the third cell/TRP is equal to or greater than a threshold value, the terminal can select a PRACH resource/preamble for the SSB index #m of the second cell/TRP and perform transmission.

Additionally or alternatively, (if there is no separate mapping setting), the terminal may select a PRACH resource assuming that the beam index-wise directions for the SSB (or CSI-RS) for the second cell/TRP and the SSB (or CSI-RS) of the first cell/TRP or the third cell/TRP are the same. For example, it may be assumed that the SSB index #k of the second cell/TRP and the SSB index #k of the first cell/TRP or the third cell/TRP have a QCL relationship with each other. Based on this, if the measured value for the SSB index #k of the first cell/TRP or the third cell/TRP is equal to or greater than a threshold value, the terminal may select a PRACH resource/preamble for the SSB index #k of the second cell/TRP to perform transmission.

On the other hand, when performing RACH with PRACH resources of the first cell/TRP or the third cell/TRP based on reasons for the second cell/TRP as described above, the terminal may perform the following operations.

The cases may be considered when there is an SSB (or CSI-RS) for the second cell/TRP, or when there is no SSB (or CSI-RS) for the second cell/TRP and there is an SSB (or CSI-RS) for a cell/TRP (e.g., the first cell/TRP or the third cell/TRP) belonging to the PRACH resource, or when there is an SSB (or CSI-RS) for the second cell/TRP but there is an SSB (or CSI-RS) for a cell/TRP (e.g., the first cell/TRP or the third cell/TRP) belonging to the PRACH resource.

In this regard, if an SSB (or CSI-RS) for the second cell/TRP is being transmitted, the terminal measures the SSB (or CSI-RS) and, based on this, selects a PRACH resource as the PRACH resource of the first cell/TRP or the third cell/TRP to perform transmission.

Additionally or alternatively, if the SSB (or CSI-RS) for the second cell/TRP is available but is not being transmitted during the DTX inactive interval, the UE may measure the SSB (or CSI-RS) of the first cell/TRP or the third cell/TRP or the reference signal (RS) in the present disclosure during the DTX inactive interval (or always regardless of DTX activation/deactivation), and select a PRACH resource based on the measurement to perform transmission.

Additionally or alternatively, if the SSB (or CSI-RS) for the second cell/TRP (based on whether it is an on-demand SSB or SSB-less cell/TRP) is not available and is not being transmitted, the UE may measure the SSB (or CSI-RS) of the first cell/TRP or the third cell/TRP or the reference signal (RS) in the present disclosure, and select a PRACH resource based on the same to perform transmission. If the RACH is triggered via DCI, the UE may measure the SSB (or CSI-RS) of the first cell/TRP or the third cell/TRP or the reference signal (RS) in the present disclosure, and select a PRACH resource based on the same to perform transmission, if the DCI does not indicate an on-demand SSB trigger.

For the above-described operations, the terminal can set a mapping relationship by beam index for the SSB (or CSI-RS) of the second cell/TRP and the SSB (or CSI-RS) of the first cell/TRP or the third cell/TRP. For example, the base station can set the SSB index #k of the first cell/TRP or the third cell/TRP to be mapped to the SSB index #m of the second cell/TRP with a QCL relationship, and can transmit the setting to the terminal through system information or a terminal-only message. Based on this, if the measurement value for the SSB index #k of the second cell/TRP is equal to or greater than a threshold value, the terminal can select a PRACH resource/preamble for the SSB index #m of the first cell/TRP or the third cell/TRP to perform transmission.

Additionally or alternatively, (if there is no separate mapping setting), the terminal may select a PRACH resource assuming that the beam index-wise directions for the SSB (or CSI-RS) for the second cell/TRP and the SSB (or CSI-RS) of the first cell/TRP or the third cell/TRP are the same. For example, it may be assumed that the SSB index #k of the second cell/TRP and the SSB index #k of the first cell/TRP or the third cell/TRP have a QCL relationship with each other. Based on this, if the measured value for the SSB index #k of the second cell/TRP is equal to or greater than a threshold value, the terminal may select a PRACH resource/preamble for the SSB index #k of the first cell/TRP or the third cell/TRP to perform transmission.

Below, a method of operating an SSB-less cell and an on-demand SSB applicable to the method proposed in the present disclosure (e.g., Embodiment 1 and/or Embodiment 2) is described.

A base station can configure/indicate for a serving cell that it is an SSB-less cell and/or that on-demand SSB is in operation via RRC message, MAC-CE, and/or DCI (cell-common, cell-specific, terminal group-common, or terminal-specific). If a terminal recognizes for a serving cell that it is an SSB-less cell and/or that on-demand SSB is in operation through reception of the configuration/indication, it can not expect SSB reception through the serving cell and can transmit a UL signal/channel configured for on-demand SSB use for an SSB request in the serving cell.

Specifically, for SCell, such information can be conveyed via RRC signaling and/or SCell activation MAC-CE for configuring and/or adding SCell. For example, when configuring and/or adding a SCell via RRC signaling, the corresponding SCell can be notified to the UE that the corresponding SCell corresponds to an SSB-less cell and that on-demand SSB is in operation. For another example, when configuring and/or adding a SCell via RRC signaling, the corresponding SCell can be set to correspond to an SSB-less cell and that on-demand SSB may be in operation, and information about whether the SCell actually corresponds to an SSB-less cell and/or that on-demand SSB is in operation can be indicated via MAC-CE.

When a SCell is activated based on the signaling mentioned above and is configured/indicated to be an SSB-less cell and/or that on-demand SSB is in operation, SSB can be transmitted on the SCell for a period of time T (e.g., the T value can be predefined or can be a value set by the base station). Alternatively, whether SSB is to be transmitted for the period of time T can be predefined or can be explicitly configured/indicated by RRC signaling or (SCell activation) MAC-CE.

In this regard, it may be necessary to set up a reference cell (ref-cell) corresponding to an SSB-less cell, and one or more candidates for the reference cell may be set up, and which cell is actually the reference cell may be set/indicated through RRC signaling or MAC-CE (indicating activation) that sets up or adds the corresponding SSB-less cell.

Additionally or alternatively, different cells may be interlocked depending on the function of the reference cell. For example, cell #A may be set/designated as a reference cell for timing sync and AGC setting of an SSB-less cell, cell #B may be set/designated as a reference cell for UL power control (or path-loss estimation), and cell #C may be set/designated as a reference cell for measuring RRM measurement instead. Alternatively, multiple reference cells may be set/designated for the same function.

For example, when 2 TAs (timing advances) are configured for an SSB-less SCell (e.g., in a multi-TRP situation or in IAB operation), a reference cell for timing sync (and AGC setting) corresponding to each TA can be configured/indicated separately. For another example, a reference cell (and a DL signal/channel transmitted from the reference cell) for the reference purpose of UL power control (or path-loss estimation) can be configured differently depending on the UL signal/channel on the SSB-less SCell. For another example, different reference cells (and DL signals/channels transmitted from the reference cell) can be configured differently depending on the type of measurement. As a specific example, for RSRP, SSB on cell #1 can be configured as a reference, and for L1-SINR, SSB or CSI-RS resource on cell #2 (or cell #1) can be configured as a reference.

Additionally or alternatively, one or more reference cells may be linked/configured/indicated for a single SSB-less cell. In this case, a priority order may be required for which of the multiple linked reference cells is to obtain timing synchronization, AGC setting, UL power control (or path-loss estimation), beam management related measurements, and/or RRM measurement functions. The priority order may be explicitly set/indicated, or if the reference cell with a higher priority order is in an inactive state or a dormant BWP is in operation, a cell corresponding to the next priority order may be replaced as the reference cell.

Such priority order can also be set/defined at signal/channel level rather than cell level. For example, SSB of PCell, CSI-RS of PCell (e.g., TRS), CSI-RS of SCell (e.g., TRS) can be set as reference for timing synchronization of SSB-less SCell (and/or for path-loss estimation), and SSB of PCell can be set/indicated as having the highest priority and CSI-RS of SCell as having the lowest priority, or a rule can be defined in advance.

A common reference cell may be set/indicated for SSB-less SCells of a group, and for this purpose, the SSB-less SCells may be grouped. For example, when SCell indices #0/1/2 are all set/indicated as SSB-less SCells and belong to the same group, the reference cells corresponding to the SCells belonging to the same group may be common. In particular, when a reference cell is set/indicated for one of the SCells belonging to the same group, it may mean that the corresponding reference cell is automatically set/indicated as a reference cell from other SCells in the same group.

Even if a reference cell corresponding to a specific SSB-less SCell (or a group to which the SCell belongs) is not configured, a default reference cell can be determined by a rule. If the SSB-less SCell belongs to a master cell group (MCG), the default reference cell can be the PCell, and if it belongs to a secondary cell group (SCG), the default cell can be the PSCell. Alternatively, if the SSB-less SCell does not belong to a primary timing advance group (pTAG) but to a secondary timing advance group (sTAG), any SCell that is not SSB-less and belongs to the same sTAG can be the default reference cell. Alternatively, the serving cell with the lowest/highest cell index can be the default reference cell.

In order to minimize the system performance degradation due to SSB-less cell operation, SSB-less cell operation may not be allowed for PCell/PSCell/PUCCH-SCell (e.g., SCell on which PUCCH transmission is configured)/PUCCH-sSCell (e.g., SCell on which PUCCH can be transmitted due to PUCCH cell switching) on which PUCCH can be transmitted. In addition, for a similar purpose, a SCell set/designated as a reference cell for an SSB-less cell may not be allowed to be deactivated or operate in dormant BWP.

The terminal may be configured with some or all of the following information for an on-demand SSB that can be transmitted on an SSB-less cell, and may be configured differently for each BWP configured in the SSB-less cell or commonly for each BWP. Multiple candidate values may be defined/configured in advance for one of the following information, and one of the values may be configured/indicated via RRC signaling for configuring/adding an SSB-less cell or MAC-CE (for SCell activation).

- Period of on-demand SSB: This can mean the (minimum) time interval during which the same SSB (candidate) index is transmitted. If the period is not set, a default value (e.g., 20 msec) is defined in advance, or the SSB period set in the reference cell can be applied as the period of on-demand SSB on the SSB-less cell.

- Transmission duration of on-demand SSB: The transmission duration can mean the period from the start to the end of on-demand SSB on an SSB-less cell. For example, when on-demand SSB is transmitted P times with a cycle of X msec from slot #n on an SSB-less cell, and SSB is no longer transmitted and can be turned off from slot #n+k, then k slots (or the absolute time corresponding to k slots or P) can be defined as the period.

- Pattern information of on-demand SSB: If the time/frequency structure may be different between legacy SSB and on-demand SSB, information about the pattern of such compressed/simplified SSB can be set.

- Power value of on-demand SSB: If path loss estimation, CSI reporting, etc. need to be performed via the SSB, the power value of the SSB may be required. If the power value is not set, the predefined default value is applied, or the SSB power value set in the target cell can be increased and applied. In addition, if the relative EPRE value between PSS/SSS/PBCH can be different from the existing SSB, the relative EPRE value can also be additionally set.

- Location of frequency resources (e.g. center frequency) where on-demand SSB is transmitted

- Information on whether the on-demand SSB is a NCD-SSB (non-cell defining-SSB) or a CD-SSB (cell defining-SSB).

If multiple reference cells can be set for an SSB-less cell, the aforementioned information corresponding to each reference cell can be set separately.

Additionally, the above-described information can also be set for SSB transmitted for a certain time T after SCell activation as in the above-described embodiment 1.

Figure 8 illustrates an on-demand SSB related procedure applicable to the present disclosure.

Referring to FIG. 8, the base station can set up an SSB-less cell, a reference cell, and/or an on-demand SSB, etc. based on the methods described in the present disclosure (S810).

The terminal may perform timing information and/or path loss estimation based on the reference cell (S820), and then select and transmit one of the configured on-demand SSB signals (S830). Here, the on-demand SSB signal may mean a UL signal/channel for requesting on-demand SSB.

After receiving the on-demand SSB signal, the base station can transmit a corresponding SSB signal (S840).

FIGS. 9 and 10 illustrate terminal operations and base station operations for performing measurements considering on-demand SSB according to embodiments of the present disclosure described above.

FIG. 9 is a drawing for explaining the operation of a terminal according to one embodiment of the present disclosure.

Referring to FIG. 9, the terminal can receive a setting for an on-demand synchronization signal block in the second cell from the first cell (S910).

For example, the first cell may be a primary cell (or PSCell) set for the terminal, and the second cell may be a secondary cell (or PSCell) set for the terminal.

For example, the first cell may be a cell to which the NES mode is not applied/considered, and the second cell may be a cell to which the NES mode is applied.

The terminal can receive instruction information related to an on-demand simultaneous signal block (S920).

For example, the instruction information can be conveyed via downlink control information (DCI).

In this regard, the indication information may include information about the measurement object. For example, the information about the measurement object may include at least one of information about a cell related to the measurement object, information about a reference signal for the cell, information about whether the reference signal is an on-demand synchronization signal block, or information about a measurement quantity. Additionally or alternatively, the indication information may include information about whether a measurement report is made. For example, the information about whether a measurement report is made may include at least one of information about a type of a measurement report, information about an uplink resource for a measurement report, or information about a time interval between the indication information and the uplink resource.

When an on-demand synchronization signal block is transmitted based on at least one of the aforementioned settings or instruction information, the terminal can report information on the measurement result for the on-demand synchronization signal block (S930).

That is, when an on-demand synchronization signal block is transmitted from a second cell, the terminal can perform measurement on the corresponding on-demand synchronization signal block and report the result thereof to the base station as quality for the second cell.

In this regard, the on-demand synchronization signal block may be transmitted for a certain period of time after the reception of the above-described instruction information. For example, information about the certain period of time may be conveyed via at least one of the above-described setting or instruction information.

If the on-demand synchronization signal block is not transmitted, the terminal may perform measurement for a specific reference signal (RS) and report information about the measurement result to the corresponding second cell. For example, the specific reference signal (RS) may be at least one of a synchronization signal block transmitted from the second cell or a reference signal related to a channel state.

That is, if an on-demand synchronization signal block is not transmitted from the second cell, the terminal can perform measurement on another reference signal transmitted from the second cell and report the result thereof to the base station as quality for the second cell.

The method described in the example of FIG. 9 can be performed by the first device (100) of FIG. 11. That is, the terminal of FIG. 11 can be implemented as the first device (100). For example, one or more processors (102) of the first device (100) of FIG. 11 can be configured to receive, through one or more transceivers (106), a setting for an on-demand synchronization signal block, receive instruction information related to the on-demand synchronization signal block, and report a measurement result thereof when the corresponding on-demand synchronization signal block is transmitted. Furthermore, one or more memories (104) of the first device (100) can store commands for performing the method described in the example of FIG. 9 or the examples described above when executed by one or more processors (102).

FIG. 10 is a diagram for explaining the operation of a base station according to one embodiment of the present disclosure.

Referring to FIG. 10, a base station can transmit a setting for an on-demand synchronization signal block in a second cell in a first cell (S1010).

For example, the first cell may be a primary cell (or PSCell) set for the terminal, and the second cell may be a secondary cell (or PSCell) set for the terminal.

For example, the first cell may be a cell to which the NES mode is not applied/considered, and the second cell may be a cell to which the NES mode is applied.

The base station can transmit instruction information related to the on-demand simultaneous signal block (S1020).

For example, the instruction information can be conveyed via downlink control information (DCI).

In this regard, the indication information may include information about the measurement object. For example, the information about the measurement object may include at least one of information about a cell related to the measurement object, information about a reference signal for the cell, information about whether the reference signal is an on-demand synchronization signal block, or information about a measurement quantity. Additionally or alternatively, the indication information may include information about whether a measurement report is made. For example, the information about whether a measurement report is made may include at least one of information about a type of a measurement report, information about an uplink resource for a measurement report, or information about a time interval between the indication information and the uplink resource.

When an on-demand synchronization signal block is transmitted based on at least one of the aforementioned settings or instruction information, the base station can receive a report including information on a measurement result for the on-demand synchronization signal block (S1030).

That is, when an on-demand synchronization signal block is transmitted from a second cell, the terminal can perform measurement on the corresponding on-demand synchronization signal block and report the result thereof to the base station as quality for the second cell.

In this regard, the on-demand synchronization signal block may be transmitted for a certain period of time after the reception of the above-described instruction information. For example, information about the certain period of time may be conveyed via at least one of the above-described setting or instruction information.

If the on-demand synchronization signal block is not transmitted, the base station can perform measurement for a specific reference signal (RS) and report the obtained measurement result as quality for the corresponding second cell. For example, the specific reference signal (RS) can be at least one of a synchronization signal block transmitted in the second cell or a reference signal related to a channel state.

That is, if an on-demand synchronization signal block is not transmitted from the second cell, the terminal can perform measurement on another reference signal transmitted from the second cell and report the result thereof to the base station as quality for the second cell.

The method described in the example of FIG. 10 can be performed by the second device (200) of FIG. 11. That is, the base station of FIG. 10 can be implemented by the second device (200). For example, one or more processors (202) of the second device (200) of FIG. 10 can be configured to transmit, through one or more transceivers (206), a setting for an on-demand synchronization signal block, transmit instruction information related to the on-demand synchronization signal block, and receive a report including a measurement result thereof when the on-demand synchronization signal block is transmitted. Furthermore, one or more memories (204) of the second device (200) can store commands for performing the method described in the example of FIG. 10 or the examples described above when executed by one or more processors (202).

General description of devices to which the present disclosure may be applied

FIG. 11 illustrates a block diagram of a wireless communication device according to one embodiment of the present disclosure.

Referring to FIG. 11, the first device (100) and the second device (200) can transmit and receive wireless signals through various wireless access technologies (e.g., LTE, LTE-A, LTE-A pro, NR, 5G, 5G-A, 6G).

A first device (100) includes one or more processors (102) and one or more memories (104), and may additionally include one or more transceivers (106) and/or one or more antennas (108). The processor (102) controls the memories (104) and/or the transceivers (106), and may be configured to implement the descriptions, functions, procedures, suggestions, methods, and/or operational flowcharts disclosed in this disclosure.

For example, the processor (102) may process information in the memory (104) to generate first information/signal, and then transmit a wireless signal including the first information/signal through the transceiver (106). In addition, the processor (102) may receive a wireless signal including second information/signal through the transceiver (106), and then store information obtained from signal processing of the second information/signal in the memory (104).

The memory (104) may be connected to the processor (102) and may store various information related to the operation of the processor (102). For example, the memory (104) may perform some or all of the processes controlled by the processor (102), or may store software codes including commands for performing the descriptions, functions, procedures, proposals, methods, and/or operational flowcharts disclosed in the present disclosure. Here, the processor (102) and the memory (104) may be part of a communication modem/circuit/chip designed to implement a wireless communication technology (e.g., LTE, NR). The transceiver (106) may be connected to the processor (102) and may transmit and/or receive wireless signals via one or more antennas (108). The transceiver (106) may include a transmitter and/or a receiver. The transceiver (106) may be used interchangeably with an RF (Radio Frequency) unit. In the present disclosure, a device may also mean a communication modem/circuit/chip.

The second device (200) includes one or more processors (202), one or more memories (204), and may additionally include one or more transceivers (206) and/or one or more antennas (208). The processor (202) may control the memories (204) and/or the transceivers (206), and may be configured to implement the descriptions, functions, procedures, suggestions, methods, and/or operational flowcharts disclosed in this disclosure. For example, the processor (202) may process information in the memory (204) to generate third information/signal, and then transmit a wireless signal including the third information/signal via the transceiver (206). Additionally, the processor (202) may receive a wireless signal including fourth information/signal via the transceiver (206), and then store information obtained from signal processing of the fourth 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 perform some or all of the processes controlled by the processor (202), or may store software codes including commands for performing the descriptions, functions, procedures, proposals, methods, and/or operational flowcharts disclosed in the present disclosure. Here, the processor (202) and the memory (204) may be part of a communication modem/circuit/chip designed to implement wireless communication technology (e.g., LTE, NR). The transceiver (206) may be connected to the processor (202) and may transmit and/or receive wireless signals via one or more antennas (208). The transceiver (206) may include a transmitter and/or a receiver. The transceiver (206) may be used interchangeably with an RF unit. In the present disclosure, a device may also mean a communication modem/circuit/chip.

Hereinafter, hardware elements of the device (100, 200) will be described in more detail. Although not limited thereto, one or more protocol layers may be implemented by one or more processors (102, 202). For example, one or more processors (102, 202) may implement one or more layers (e.g., functional layers such as PHY, MAC, RLC, PDCP, RRC, SDAP). One or more processors (102, 202) may generate one or more Protocol Data Units (PDUs) and/or one or more Service Data Units (SDUs) according to the descriptions, functions, procedures, proposals, methods, and/or operational flowcharts disclosed in the present disclosure. One or more processors (102, 202) may generate messages, control information, data, or information according to the descriptions, functions, procedures, proposals, methods, and/or operational flowcharts disclosed in the present disclosure. One or more processors (102, 202) can generate signals (e.g., baseband signals) including PDUs, SDUs, messages, control information, data or information according to the functions, procedures, suggestions and/or methodologies disclosed in this disclosure, and provide the signals to one or more transceivers (106, 206). One or more processors (102, 202) can receive signals (e.g., baseband signals) from one or more transceivers (106, 206) and obtain PDUs, SDUs, messages, control information, data or information according to the descriptions, functions, procedures, suggestions, methods and/or operational flowcharts disclosed in this disclosure.

The one or more processors (102, 202) may be referred to as a controller, a microcontroller, a microprocessor, or a microcomputer. The one or more processors (102, 202) may be implemented by hardware, firmware, software, or a combination thereof. For example, one or more Application Specific Integrated Circuits (ASICs), one or more Digital Signal Processors (DSPs), one or more Digital Signal Processing Devices (DSPDs), one or more Programmable Logic Devices (PLDs), or one or more Field Programmable Gate Arrays (FPGAs) may be included in the one or more processors (102, 202). The descriptions, functions, procedures, suggestions, methods, and/or operational flowcharts disclosed in this disclosure 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, suggestions, methods and/or operational flowcharts disclosed in this disclosure may be implemented using firmware or software configured to perform one or more of the following: included in one or more processors (102, 202), or stored in one or more memories (104, 204) and driven by one or more of the processors (102, 202). The descriptions, functions, procedures, suggestions, methods and/or operational flowcharts disclosed in this disclosure may be implemented using firmware or software in the form of codes, instructions and/or sets of instructions.

One or more memories (104, 204) may be coupled to one or more processors (102, 202) and may store various forms of data, signals, messages, information, programs, codes, instructions and/or commands. The one or more memories (104, 204) may be comprised of ROM, RAM, EPROM, flash memory, hard drives, registers, cache memory, computer readable storage media and/or combinations thereof. The one or more memories (104, 204) may be located internally and/or externally to the one or more processors (102, 202). Additionally, the one or more memories (104, 204) may be coupled to the one or more processors (102, 202) via various technologies, such as wired or wireless connections.

One or more transceivers (106, 206) can transmit user data, control information, wireless signals/channels, etc., as described in the methods and/or flowcharts of the present disclosure, to one or more other devices. One or more transceivers (106, 206) can receive user data, control information, wireless signals/channels, etc., as described in the descriptions, functions, procedures, suggestions, methods and/or flowcharts of the present disclosure, from one or more other devices. For example, one or more transceivers (106, 206) can be coupled to one or more processors (102, 202) and can transmit and receive wireless signals. For example, one or more processors (102, 202) can control one or more transceivers (106, 206) to transmit user data, control information, or wireless signals to one or more other devices. Additionally, one or more processors (102, 202) may control one or more transceivers (106, 206) to receive user data, control information, or wireless signals from one or more other devices. Additionally, one or more transceivers (106, 206) may be coupled to one or more antennas (108, 208), and one or more transceivers (106, 206) may be configured to transmit and receive user data, control information, wireless signals/channels, and the like, as described in the description, function, procedure, proposal, method, and/or operational flowchart, etc. disclosed in this disclosure, via one or more antennas (108, 208). In the present disclosure, one or more antennas may be multiple physical antennas, or multiple logical antennas (e.g., antenna ports). One or more transceivers (106, 206) may convert received user data, control information, 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 one or more processors (102, 202). One or more transceivers (106, 206) may convert processed user data, control information, wireless signals/channels, etc. from baseband signals to RF band signals using one or more processors (102, 202). For this purpose, one or more transceivers (106, 206) may include an (analog) oscillator and/or filter.

The embodiments described above are combinations of components and features of the present disclosure in a given form. Each component or feature should be considered optional unless explicitly stated otherwise. Each component or feature may be implemented in a form that is not combined with other components or features. In addition, it is also possible to combine some components and/or features to form an embodiment of the present disclosure. The order of operations described in the embodiments of the present disclosure may be changed. Some components or features of one embodiment may be included in another embodiment, or may be replaced with corresponding components or features of another embodiment. It is obvious that claims that do not have an explicit citation relationship in the scope of the patent may be combined to form an embodiment or may be included as a new claim by post-application amendment.

It will be apparent to those skilled in the art that the present disclosure may be embodied in other specific forms without departing from the essential characteristics of the present disclosure. Accordingly, the above detailed description should not be construed as limiting in all respects but should be considered as illustrative. The scope of the present disclosure should be determined by a reasonable interpretation of the appended claims, and all changes within the equivalent scope of the present disclosure are intended to be included in the scope of the present disclosure.

The scope of the present disclosure includes software or machine-executable instructions (e.g., an operating system, an application, firmware, a program, etc.) that cause operations according to the various embodiments to be executed on a device or a computer, and a non-transitory computer-readable medium having such software or instructions stored thereon and executable on the device or computer. Instructions that can be used to program a processing system to perform the features described in the present disclosure can be stored on/in a storage medium or a computer-readable storage medium, and a computer program product including such a storage medium can be used to implement the features described in the present disclosure. The storage medium can include, but is not limited to, high-speed random access memory, such as DRAM, SRAM, DDR RAM, or other random access solid state memory devices, and can include non-volatile memory, such as one or more magnetic disk storage devices, optical disk storage devices, flash memory devices, or other non-volatile solid state storage devices. The memory optionally includes one or more storage devices remotely located from the processor(s). The memory or alternatively the non-volatile memory device(s) within the memory comprises a non-transitory computer-readable storage medium. The features described in this disclosure may be incorporated into software and/or firmware stored on any one of the machine-readable media to control the hardware of the processing system and to allow the processing system to interact with other mechanisms that utilize results according to embodiments of the present disclosure. Such software or firmware may include, but is not limited to, application code, device drivers, operating systems, and execution environments/containers.

Here, the wireless communication technology implemented in the device (100, 200) of the present disclosure may include LTE, NR, and 6G, as well as Narrowband Internet of Things for low-power communication. At this time, for example, NB-IoT technology may be an example of LPWAN (Low Power Wide Area Network) technology, and may be implemented with standards such as LTE Cat NB1 and/or LTE Cat NB2, and is not limited to the above-described names. Additionally or alternatively, the wireless communication technology implemented in the device (100, 200) of the present disclosure may perform communication based on LTE-M technology. At this time, for example, LTE-M technology may be an example of LPWAN technology, and may be called by various names such as eMTC (enhanced Machine Type Communication). For example, the LTE-M technology may be implemented by at least one of various standards such as 1) LTE CAT 0, 2) LTE Cat M1, 3) LTE Cat M2, 4) LTE non-BL (non-Bandwidth Limited), 5) LTE-MTC, 6) LTE Machine Type Communication, and/or 7) LTE M, and is not limited to the above-described names. Additionally or alternatively, the wireless communication technology implemented in the device (100, 200) of the present disclosure may include at least one of ZigBee, Bluetooth, and Low Power Wide Area Network (LPWAN) considering low-power communication, and is not limited to the above-described names. For example, the ZigBee technology can create PAN (personal area networks) related to small/low-power digital communication based on various standards such as IEEE 802.15.4, and may be called by various names.

The method proposed in this disclosure has been described with a focus on examples applied to 3GPP LTE/LTE-A, 5G, and 6G systems, but it can be applied to various wireless communication systems in addition to 3GPP LTE/LTE-A, 5G, and 6G systems.

Claims (15)

A method performed by a terminal in a wireless communication system, the method comprising: In a first cell, a step of receiving a setting for an on-demand synchronization signal block in a second cell; A step of receiving instruction information related to the above-mentioned on-demand synchronization signal block; A step of reporting information about a measurement result for said on-demand synchronization signal block based on at least one of said setting or said instruction information, wherein said on-demand synchronization signal block is transmitted; A method in which the above-described on-demand synchronization signal block is transmitted for a certain period of time after receiving the above-described instruction information. In the first paragraph, A method further comprising the step of performing measurement on a specific reference signal based on the above-mentioned on-demand synchronization signal block not being transmitted and reporting information on the measurement result for the second cell. In the second paragraph, A method wherein the specific reference signal is at least one of a synchronization signal block transmitted in the second cell or a reference signal related to a channel state. In the first paragraph, A method wherein the first cell is a primary cell set for the terminal, and the second cell is a secondary cell set for the terminal. In the first paragraph, A method in which the above instruction information is transmitted via downlink control information. In the first paragraph, A method wherein the above instruction information includes information about a measurement object. In Article 6, A method according to claim 1, wherein the information about the measurement object includes at least one of information about a cell related to the measurement object, information about a reference signal for the cell, information about whether the reference signal is an on-demand synchronization signal block, or information about a measurement quantity. In the first paragraph, A method wherein the above instruction information includes information on whether a measurement is reported. In Article 8, A method wherein the information on whether the measurement report is made includes at least one of information on the type of the measurement report, information on uplink resources for the measurement report, or information on a time interval between the indication information and the uplink resources. In the first paragraph, A method wherein the second cell corresponds to a cell to which a network energy saving mode is applied. In a device on a wireless communication system, the device: one or more transceivers; and comprising one or more processors coupled to said one or more transceivers; One or more of the above processors: In the first cell, a setting for an on-demand synchronization signal block in the second cell is received; Receive instruction information related to the above-mentioned on-demand synchronization signal block; Based on at least one of the above settings or the above instruction information, the on-demand synchronization signal block is transmitted, and information on the measurement result for the on-demand synchronization signal block is set to be reported. The above-mentioned on-demand synchronization signal block is transmitted for a certain period of time after the reception of the above-mentioned instruction information, the device. A method performed by a base station in a wireless communication system, the method comprising: A step of transmitting, in a first cell, a setting for an on-demand synchronization signal block in a second cell; A step of transmitting instruction information related to the above-mentioned on-demand synchronization signal block; A step of receiving a report including information on a measurement result for the on-demand synchronization signal block, based on at least one of the above settings or the above instruction information, based on which the on-demand synchronization signal block is transmitted, A method in which the above-described on-demand synchronization signal block is transmitted for a certain period of time after receiving the above-described instruction information. In a device on a wireless communication system, the device: one or more transceivers; and comprising one or more processors coupled to said one or more transceivers; One or more of the above processors: In the first cell, transmit a setting for an on-demand synchronization signal block in the second cell; Transmitting instruction information related to the above-mentioned on-demand synchronization signal block; Based on at least one of the above settings or the above instruction information, a report including information on a measurement result for the on-demand synchronization signal block is set to be received based on the on-demand synchronization signal block being transmitted, The above-mentioned on-demand synchronization signal block is transmitted for a certain period of time after the reception of the above-mentioned instruction information, the device. A processing device configured to control a station (STA) in a wireless local area network (WLAN) system, wherein the processing device: one or more processors; and A processing device comprising one or more computer memories operatively connected to said one or more processors and storing instructions that, when executed by said one or more processors, perform a method according to any one of claims 1 to 10. One or more non-transitory computer-readable media storing one or more instructions, A computer-readable medium, wherein said one or more commands are executed by one or more processors to control a device in a wireless LAN system to perform a method according to any one of claims 1 to 10.

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