User equipment, base station, method for user equipment, and method for base station

Abstract

The present disclosure relates to a user equipment (UE), a base station, a method for a UE, and a method for a base station. More specifically, the UE comprises: a transceiver that, in operation, receives a power level indicator from a base station, the power level indicator indicating a power level of a channel state information - reference signal (CSI-RS) resource and / or indicating whether the CSI-RS resource is transmitted by the base station. The UE further comprises: a circuit that, in operation, operates in response to the power level and / or whether the CSI-RS resource is transmitted by the base station.

Description

[Technical Field]

[0001] 1.Technical Field FIELD OF THE DISCLOSURE The present disclosure relates to transmitting and receiving signals in a communication system. In particular, the present disclosure relates to methods and apparatus for such transmission and reception. [Background technology]

[0002] 2. Description of Related Technology The 3rd Generation Partnership Project (3GPP)® is working on technical specifications for next-generation cellular technology (also known as fifth generation (5G)), including New Radio (NR) access technology (RAT) operating in the frequency range up to 100 GHz. NR is the successor to technologies represented by Long Term Evolution (LTE) and LTE Advanced (LTE-A).

[0003] In systems such as LTE and NR, further improvements and options may facilitate efficient operation of the communication system and certain devices associated with the communication system. [Prior art documents] [Non-patent literature]

[0004] [Non-Patent Document 1] 3GPP TS 38.300 v15.6.0 [Non-patent document 2] 3GPP TS 38.211 v16.2.0 [Non-patent document 3] 3GPP TS 23.501 v16.1.0 Summary of the Invention [Problem to be solved by the invention]

[0005] Non-limiting examples of the present disclosure contribute to reducing network power consumption while at the same time procedures performed by the UE are not affected by actions taken by the base station. [Means for solving the problem]

[0006] One embodiment of the present disclosure features a user equipment (UE). The UE, in operation, comprises a transceiver that receives a power level indicator from a base station. The power level indicator indicates a power level of a Channel State Information-Reference Signal (CSI-RS) resource and / or indicates whether the CSI-RS resource is transmitted by the base station. The UE, in operation, further comprises circuitry that operates in response to the power level and / or whether the CSI-RS resource is transmitted by the base station.

[0007] These comprehensive or specific aspects may be realized as a system, a method, an integrated circuit, a computer program, or a recording medium, or may be realized as any combination of a system, an apparatus, a method, an integrated circuit, a computer program, and a recording medium.

[0008] Further advantages and benefits of an embodiment of the present disclosure will become apparent from the specification and drawings. Such advantages and / or benefits may be provided by some embodiments and features described in the specification and drawings, respectively, but not necessarily all of them may be provided to obtain one or more identical features.

[0009] The following exemplary embodiments are described in more detail with reference to the accompanying drawings. [Brief explanation of the drawings]

[0010] [Figure 1] Diagram of an example architecture of a 3GPP NR system [Figure 2]Schematic diagram showing functional separation between NG-RAN and 5GC [Figure 3] Sequence diagram of RRC connection setup / reconfiguration procedure [Figure 4] Schematic showing enhanced mobile broadband (eMBB), massive machine-type communications (mMTC), and ultra-reliable low-latency communications (URLLC) usage scenarios [Figure 5] Block diagram illustrating an exemplary 5G system architecture for a non-roaming scenario [Figure 6a] Schematic diagram showing aspects of digital beamforming [Figure 6b] Schematic diagram showing aspects of analog beamforming [Figure 7] A block diagram of a communication system including user equipment and a base station having respective structures. [Figure 8a] Block diagram showing the functional structure of the processing circuitry on the user equipment side [Figure 8b] Block diagram showing the functional structure of the processing circuit on the base station side [Figure 9] 1 is a flowchart illustrating exemplary steps performed by a user equipment and exemplary steps performed by a base station. [Figure 10] Schematic diagram showing an example of signaling a power level indicator via a group-common DCI [Figure 11] 1 is a flowchart illustrating exemplary steps performed by a UE. [Figure 12] Schematic diagram illustrating another example of signaling a power level indicator via a group-common DCI. DETAILED DESCRIPTION OF THE INVENTION

[0011] <5G NR system architecture and protocol stack> 3GPP is working on the next release of fifth-generation cellular technology (known simply as "5G"), which includes the development of a new radio access technology (NR) that will operate in frequencies up to 100 GHz. The first version of the 5G standard was completed at the end of 2017, allowing for the testing and commercial deployment of smartphones compliant with the 5G NR standard.

[0012] In particular, the overall system architecture assumes an NG-RAN (Next Generation - Radio Access Network) with gNBs, which terminate the NG radio access user plane (SDAP / PDCP / RLC / MAC / PHY) protocols and control plane (Radio Resource Control (RRC) protocols) towards UEs. The gNBs are interconnected with each other by an Xn interface. The gNBs are also connected to an NGC (Next Generation Core) by a Next Generation (NG) interface, more specifically to an AMF (Access and Mobility Management Function) (e.g., a specific core entity running the AMF) by an NG-C interface, and to a UPF (User Plane Function) (e.g., a specific core entity running the UPF) by an NG-U interface. The NG-RAN architecture is shown in Figure 1 (see, for example, Section 4 of Non-Patent Document 1).

[0013] The user plane protocol stack in NR (see, for example, Section 4.4.1 of Non-Patent Document 1) includes a PDCP (Packet Data Convergence Protocol) sublayer, an RLC (Radio Link Control) sublayer, and a MAC (Medium Access Control) sublayer, which are terminated at the gNB on the network side. In addition, a new access stratum (AS) sublayer (SDAP, Service Data Adaptation Protocol) is introduced above PDCP (see, for example, Section 6.5 of Non-Patent Document 1). NR also defines a control plane protocol stack (see, for example, Section 4.4.2 of Non-Patent Document 1). An overview of Layer 2 functions is provided in Section 6 of Non-Patent Document 1. The functions of the PDCP, RLC, and MAC sublayers are respectively described in Sections 6.4, 6.3, and 6.2 of 3GPP TS 2.0. The functions of the RRC layer are described in Section 7 of 3GPP TS 2.0.

[0014] For example, the Medium-Access-Control layer handles scheduling and scheduling-related functions, including multiplexing logical channels and handling various numerologies.

[0015] The physical layer (PHY) is responsible for, for example, coding, PHY HARQ processing, modulation, multi-antenna processing, and mapping of signals to appropriate physical time-frequency resources. The physical layer also handles mapping of transport channels to physical channels. The physical layer provides services to the MAC layer in the form of transport channels. A physical channel corresponds to a set of time-frequency resources used for transmitting a specific transport channel, and each transport channel is mapped to a corresponding physical channel. For example, physical channels are the PRACH (Physical Random Access Channel), PUSCH (Physical Uplink Shared Channel), and PUCCH (Physical Uplink Control Channel) for the uplink, and the PDSCH (Physical Downlink Shared Channel), PDCCH (Physical Downlink Control Channel), and PBCH (Physical Broadcast Channel) for the downlink.

[0016] NR use cases / deployment scenarios include enhanced mobile broadband (eMBB), ultra-reliable and low-latency communications (URLLC), and / or massive machine-type communications (mMTC), which have diverse requirements for data rates, latency, and coverage. For example, eMBB is expected to support peak data rates (20 Gbps downlink and 10 Gbps uplink) and user-perceived data rates on the order of three times those offered by IMT-Advanced. In contrast, URLLC has more stringent requirements, including extremely low latency (user plane latency of 0.5 ms for UL and DL, respectively) and high reliability (1-10 Mbps within 1 ms). -5) and mMTC requires high connection density (1 km in urban environments). 2 1,000,000 devices per second), wide coverage in harsh environments, and extremely long battery life (15 years) to lower device costs may preferably be required.

[0017] Therefore, an OFDM numerology (e.g., subcarrier spacing, OFDM symbol length, cyclic prefix (CP) length, number of symbols per scheduling interval) suitable for one use case may not work well for another use case. For example, low-latency services may preferably require a shorter symbol length (and therefore a larger subcarrier spacing) and / or fewer symbols per scheduling interval (also referred to as TTI) than mMTC services. Furthermore, deployment scenarios with large channel delay spreads may preferably require a longer CP length than scenarios with small delay spreads. To maintain a similar CP overhead, the subcarrier spacing should be optimized depending on the delay spread. In NR, more than one value of subcarrier spacing may be supported. Therefore, subcarrier spacings of 15 kHz, 30 kHz, 60 kHz, ... are currently being considered. The symbol length T u and the subcarrier spacing Δf is given by the formula (Δf=1 / T u ) As in LTE systems, the term "resource element" can be used to denote the smallest resource unit consisting of one subcarrier for the length of one OFDM / SC-FDMA symbol.

[0018] In the new wireless system 5G-NR, for each numerology and carrier, a resource grid of subcarriers and OFDM symbols is defined for both the uplink and the downlink. Each element in the resource grid is called a resource element and is identified based on the frequency index in the frequency domain and the symbol position in the time domain (see, for example, Section 4 of Non-Patent Document 2). For example, downlink transmission and uplink transmission are set in a frame having a time length of 10 ms. Each frame consists of 10 subframes each having a time length of 1 ms. In the implementation of 5G NR, the number of consecutive OFDM symbols per subframe depends on the setting of the subcarrier spacing. For example, in the case of a subcarrier spacing of 15 kHz, the subframe has 14 OFDM symbols (assuming a normal cyclic prefix, similar to an LTE-compliant implementation). On the other hand, in the case of a subcarrier spacing of 30 kHz, the subframe has two slots, and each slot contains 14 OFDM symbols.

[0019] <Split of 5G NR Functions between NG-RAN and 5GC> Figure 2 shows the split of functions between NG-RAN and 5GC. The logical nodes of NG-RAN are gNB or ng-eNB. The logical nodes of 5GC are AMF, UPF, and SMF.

[0020] In particular, gNB and ng-eNB handle the following main functions. - Functions of radio resource management such as radio bearer control, radio admission control, connection mobility control, and dynamic resource allocation (scheduling) to the UE in both the uplink and the downlink - IP header compression, encryption, and integrity protection of data - AMF selection at UE attach time when routing to the AMF cannot be determined from information provided by the UE - Routing of user plane data to the UPF - Routing of control plane information to AMF - Establishing and releasing connections - scheduling and sending of paging messages - System broadcast information (sent from AMF or OAM) (scheduling and transmission) - Configuring measurements and measurement reporting for mobility and scheduling - Transport-level packet marking in the uplink - Session Management - Network slicing support - QoS flow management and mapping to data radio bearers - Support for UEs in RRC_INACTIVE state - Non-Access Stratum (NAS) message delivery function - Radio Access Network Sharing - Dual Connectivity - Close interworking between NR and E-UTRA

[0021] The Access and Mobility Management Function (AMF) handles the following main functions: - Termination of Non-Access Stratum (NAS) signaling - NAS signaling security - Access Stratum (AS) security control - Core Network (CN) inter-node signaling for mobility between 3GPP access networks - Reachability for idle mode UEs (including control and execution of paging retransmissions) - Registration Area Management - Support for intra-system and inter-system mobility - Access Authentication - Access authentication, including roaming rights checks - Mobility management controls (subscriptions and policies) - Network slicing support - Selection of Session Management Function (SMF)

[0022] Furthermore, the User Plane Function (UPF) handles the following main functions: - Anchor points for intra-RAT / inter-RAT mobility (when applicable) - External PDU session points for interconnection with data networks - Packet routing and forwarding - User plane portion of packet inspection and policy rule enforcement - Traffic Usage Report - Uplink classifier to support routing of traffic flows to the data network - Branching points to support multi-homed PDU sessions - User plane QoS processing (e.g., packet filtering, gating, UL / DL rate enforcement) - Verification of uplink traffic (mapping from SDF to QoS flow) - Downlink packet buffering and downlink data notification triggering

[0023] Finally, the Session Management Function (SMF) handles the following major functions: - Session Management - UE IP address allocation and management - UP function selection and control - Configuration of traffic steering in the user plane function (UPF) for routing traffic to the correct destination - Policy enforcement and QoS control part - Downlink data notification

[0024] <Procedures for establishment and reconfiguration of RRC connection> Figure 3 shows the interaction among the UE, gNB, and AMF (5GC entity) in the NAS part when the UE transitions from RRC_IDLE to RRC_CONNECTED (see, for example, Non-Patent Document 1).

[0025] RRC is the upper layer signaling (protocol) used for the configuration of the UE and gNB. In particular, in this transition, the AMF creates UE context data (including, for example, PDU session context, security keys, UE radio capabilities, UE security capabilities, etc.) and sends it to the gNB by means of an INITIAL CONTEXT SETUP REQUEST (Initial Context Setup Request). Next, the gNB activates the AS security with the UE, which is executed by the gNB sending a SecurityModeCommand message to the UE and the UE responding to the gNB with a SecurityModeComplete message. Thereafter, the gNB executes reconfiguration to establish signaling radio bearer 2 (SRB_{2}) and data radio bearer (DRB: Data Radio Bearer), which is by the gNB sending an RRCReconfiguration message to the UE and the gNB receiving RRCReconfigurationComplete from the UE in response. In the case of a signaling-only connection, since SRB_{2} and DRB are not established, these steps related to RRCReconfiguration are skipped. Finally, the gNB notifies the AMF by means of an INITIAL CONTEXT SETUP RESPONSE (Initial Context Setup Response) that the establishment procedure has been completed.

[0026] Accordingly, the present disclosure provides a fifth generation core (5GC) entity (e.g., AMF, SMF, etc.) having, in operation, a control circuit that establishes a next generation (NG) connection with a gNodeB such that a signaling radio bearer is established between the gNodeB and a user equipment (UE), and a transmitter that, in operation, transmits an initial context setup message to the gNodeB over the NG connection. In particular, the gNodeB transmits radio resource control (RRC) signaling including a resource allocation configuration information element to the UE over the signaling radio bearer. The UE then performs uplink transmission or downlink reception based on the resource allocation configuration.

[0027] <IMT usage scenarios after 2020> Figure 4 illustrates some of the use cases for 5G NR. The 3GPP NR (3rd Generation Partnership Project New Radio) is considering three use cases envisioned for IMT-2020 to support a wide variety of services and applications. Phase 1 specifications for enhanced mobile broadband (eMBB) have been finalized. Current and future work includes standardization for ultra-reliable and low-latency communications (URLLC) and large-scale machine-type communications, in addition to further extending eMBB support. Figure 4 illustrates some example IMT usage scenarios envisioned for 2020 and beyond (see, for example, Figure 2 in ITU-R M.2083).

[0028] URLLC use cases have stringent requirements for capabilities such as throughput, latency, and availability, and are envisioned as one of the enablers for future vertical applications, such as wireless control of industrial manufacturing or production processes, remote medical surgery, power distribution automation in smart grids, and transportation safety. URLLC's ultra-high reliability is supported by identifying technologies to meet the requirements set by TR 38.913. For NR URLLC in Release 15, key requirements include a user plane target latency of 0.5 ms for the uplink (UL) and 0.5 ms for the downlink (DL). A typical URLLC requirement for a single packet transmission is a block error rate (BLER) of 1E-5 for a 32-byte packet size with a 1-ms user plane latency.

[0029] From a physical layer perspective, there are several possible ways to improve reliability. Current scope for improving reliability includes defining a separate CQI table for URLLC, a more compact DCI format, PDCCH repetition, etc. However, as NR becomes more stable and developed (a key requirement for NR URLLC), the scope for achieving ultra-high reliability may expand. Specific use cases for NR URLLC in Release 15 include augmented reality / virtual reality (AR / VR), e-health, e-safety, and mission-critical applications.

[0030] Furthermore, technology enhancements targeted at NR URLLC target latency improvement and reliability enhancement. Technology enhancements for latency improvement include configurable numerology, non-slot-based scheduling with flexible mapping, grant-free (configured grant) uplink, slot-level repetition of data channels, and downlink preemption. Preemption means that a transmission for which resources have already been allocated is aborted and the already allocated resources are used for another transmission requested later with smaller latency / higher priority requirements. Thus, an already granted transmission is preempted by a later transmission. Preemption applies regardless of the specific service type. For example, a transmission of service type A (URLLC) can be preempted by a transmission of service type B (e.g., eMBB). Technology enhancements for reliability improvement include dedicated CQI / MCS tables for a target BLER of 1E-5.

[0031] The mMTC (Massive Machine Type Communication) use case is characterized by a very large number of connected devices transmitting relatively small amounts of data that are generally latency sensitive. The devices need to be low cost and have extremely long battery life. From an NR perspective, utilizing very narrow bandwidth portions is one possible solution to achieve power savings from the UE perspective, enabling long battery life.

[0032] As mentioned above, it is expected that the range of reliability in NR will expand. One key requirement for all cases, especially for URLLC and mMTC, is high or ultra-high reliability. Several mechanisms can be considered to improve reliability from a radio perspective and a network perspective. In general, there are several key areas that can help improve reliability. These areas include compact control channel information, data channel / control channel repetition, and diversity related to the frequency, time, and / or spatial domains. These areas are generally applicable to reliability, regardless of the specific communication scenario.

[0033] Additional use cases with more stringent requirements are envisioned for NR URLLC, such as factory automation, transportation, and power distribution. The more stringent requirements include higher reliability (up to 10 times faster), depending on the use case. -6 level), higher availability, packet size up to 256 bytes, time synchronization on the order of a few microseconds (values ​​range from 1 to a few microseconds depending on the frequency range), and short latency on the order of 0.5 to 1 ms (target latency for the user plane in particular is 0.5 ms).

[0034] Furthermore, for NR URLLC, there can be several technical enhancements from the perspective of the physical layer. In particular, enhancements related to PDCCH (Physical Downlink Control Channel) include compact DCI, repetition of PDCCH, and increased PDCCH monitoring. Also, enhancements related to UCI (Uplink Control Information) include enhancement of HARQ (Hybrid Automatic Repeat Request) and enhancement of CSI feedback. Additionally, enhancements of PUSCH related to mini-slot level hopping and retransmission / repetition have also been recognized. The term "mini-slot" means a transmission time interval (TTI: Transmission Time Interval) that contains a smaller number of symbols than a slot (a slot contains, for example, 14 symbols).

[0035] <QoS Control> The 5G QoS (Quality of Service) model is based on QoS flows and supports both QoS flows that require a guaranteed flow bit rate (GBR QoS flows) and QoS flows that do not require a guaranteed flow bit rate (non-GBR QoS flows). Therefore, at the NAS level, a QoS flow is the finest granularity for QoS differentiation in a PDU session. A QoS flow is identified within a PDU session by a QoS flow ID (QFI) that is transmitted within the encapsulation header through the NG-U interface.

[0036] The 5GC establishes one or more PDU sessions for each UE. The NG-RAN establishes at least one Data Radio Bearer (DRB) for each UE along with the PDU session, and can then configure additional DRBs for the QoS flows of that PDU session (as determined by the NG-RAN, e.g., as described above with reference to Figure 3). The NG-RAN maps packets belonging to different PDU sessions to different DRBs. NAS-level packet filters in the UE and 5GC associate UL and DL packets with QoS flows, and AS-level mapping rules in the UE and NG-RAN associate UL and DL QoS flows with DRBs.

[0037] Figure 5 shows the 5G NR non-roaming reference architecture (see Section 4.23 of Non-Patent Document 3). Application Functions (AFs) (e.g., external application servers handling 5G services as exemplified in Figure 4) interact with the 3GPP Core Network to provide services. For example, they support application influence on traffic routing, access Network Exposure Functions (NEFs), or interact with a policy framework (see Policy Control Function (PCF)) for policy control (e.g., QoS control). Based on the operator's deployment, application functions deemed trusted by the operator can be allowed to interact directly with the relevant Network Functions. Application Functions not permitted by the operator to directly access Network Functions interact with the relevant Network Functions using an external exposure framework via the NEF.

[0038] Figure 5 shows further functional units of the 5G architecture: Network Slice Selection Function (NSSF), Network Repository Function (NRF), Unified Data Management (UDM), Authentication Server Function (AUSF), Access and Mobility Management Function (AMF), Session Management Function (SMF), and Data Network (DN) (e.g., operator services, internet access, or third-party services). All or part of the core network functions and application services may be located and run in a cloud computing environment.

[0039] Therefore, the present disclosure provides an application server (e.g., an AF in a 5G architecture) having: a transmitter unit that, in operation, sends a request including QoS requirements for at least one of a URLLC service, an eMMB service, and an mMTC service to at least one of 5GC functions (e.g., an NEF, an AMF, an SMF, a PCF, an UPF, etc.) to establish a PDU session including a radio bearer between a gNodeB and a UE in accordance with the QoS requirements; and a control circuit that, in operation, executes the above services using the established PDU session.

[0040] <terminal> A terminal, user terminal, user device, mobile station, or mobile node is referred to as user equipment (UE) in LTE and NR. User equipment may be a mobile device or communication device, such as a wireless telephone, smartphone, tablet computer, or universal serial bus (USB) stick with user equipment functionality. However, the term mobile device is not limited thereto; in general, a relay may also have such mobile device functionality or function as a relay. For example, a terminal is a physical entity (physical node) in a communication network. Furthermore, a communication device may be any machine-type communication device, such as an IoT device. A node may have several functional entities. A functional entity refers to a software or hardware module that implements and / or provides a given set of functions to the same node or other nodes or other functional entities of the network. A node may have one or more interfaces that attach the node to a communication facility or medium over which the node can communicate. Similarly, a network entity may have logical interfaces that attach the functional entity to a communication facility or medium over which the functional entity may communicate with other functional entities or corresponding nodes.

[0041] <Base station> In the present disclosure, a base station may be, for example, a Transmission Reception Point (TRP), a cluster head, an access point, a Remote Radio Head (RRH), an eNodeB (eNB), a gNodeB (gNB), a Base Station (BS), a Base Transceiver Station (BTS), a base unit, or a gateway. Furthermore, in sidelink communication, a terminal may be used instead of a base station. The base station may be a relay device that relays communication between an upper node and a terminal. The base station may be a roadside unit. The base station may be, for example, a scheduling node or a network node that forms part of a network for providing services to terminals. In particular, the base station may provide wireless access to terminals. Communication between a terminal and a base station is typically standardized and can be defined by different layers, such as PHY, MAC, and RRC. In LTE and NR, the air interface protocol stack includes a physical layer, a medium access layer (MAC), and upper layers. The control plane is provided with a radio resource control protocol, which is an upper layer protocol. Through RRC, base stations can control the configuration of terminals, and terminals can communicate with base stations to perform control tasks such as establishing and modifying connections and bearers, measurements, and other functions. The term used in LTE is eNB (or eNodeB), and the term currently used in 5G NR is gNB. The term base station or radio base station in this specification refers to a physical entity in a communication network. Similar to a mobile station, a base station may have several functional entities. A functional entity refers to a software or hardware module that implements and / or provides a given set of functions to other functional entities of the same node or other nodes or networks. The physical entity performs several control tasks for communication devices, including one or more of scheduling and configuration.It should be noted that base station functionality and communication device functionality may also be integrated within a single device. For example, a mobile terminal may also implement the functionality of a base station for other terminals. The term used in LTE is eNB (or eNodeB), and the term currently used in 5G NR is gNB.

[0042] <Frequency band> The present disclosure may be applied to both licensed and unlicensed bands.

[0043] <Uplink / Downlink / Sidelink> The present disclosure may be applied to any of the uplink, downlink, and sidelink.

[0044] For example, the present disclosure may be applied to uplink channels such as PUSCH, PUCCH, and PRACH, downlink channels such as PDSCH, PDCCH, and PBCH, and sidelinks such as PSSCH (Physical Sidelink Shared Channel), PSCCH (Physical Sidelink Control Channel), and PSBCH (Physical Sidelink Broadcast Channel).

[0045] The PDCCH, PDSCH, PUSCH, and PUCCH are examples of a downlink control channel, a downlink data channel, an uplink data channel, and an uplink control channel, respectively. The PSCCH and PSSCH are examples of a sidelink control channel and a sidelink data channel, respectively. The PBCH and PSBCH are examples of a broadcast channel, and the PRACH is an example of a random access channel.

[0046] <Data channel / control channel> The present disclosure may be applied to both data channels and control channels. The channels in this disclosure may be replaced with data channels including PDSCH, PUSCH, and PSSCH, and / or control channels including PDCCH, PUCCH, PBCH, PSCCH, and PSBCH.

[0047] <harq-ack> HARQ-ACK (Hybrid Automatic Repeat Request - Acknowledgement) is a signaling mechanism used in wireless communication networks to enable error correction and retransmission of data. HARQ-ACK allows a receiving device to inform a transmitting device about whether a transmitted packet was successfully received, so that the sender can send the next packet or retransmit the same packet. HARQ-ACK feedback can enable efficient use of the wireless channel and help improve data transmission reliability.

[0048] <Reference signal> In this disclosure, a reference signal is a signal known to both the base station and the UE, and each reference signal may be referred to as a reference signal (RS) or a pilot signal. A reference signal may be any of a DMRS, a Channel State Information-Reference Signal (CSI-RS), a Tracking Reference Signal (TRS), a Phase Tracking Reference Signal (PTRS), a Cell-specific Reference Signal (CRS), and a Sounding Reference Signal (SRS).

[0049] <Channel State Information-Reference Signal (CSI-RS)> Channel State Information-Reference Signal (CSI-RS) is a signal used in LTE and 5G NR to measure the quality of the radio channel between a UE and a base station. CSI-RS may be transmitted periodically by the base station in specific resource elements (resources) in the frequency domain, and the UE uses the received CSI-RS to estimate the channel quality that can be used for beamforming and other techniques. The UE can also use CSI-RS for feedback to the base station indicating the modulation and coding scheme that can be supported on the current channel. CSI-RS is a component for providing high data rates and reliable communication.

[0050] <CSI-RS Resource Set Group> A CSI-RS Resource Set Group is a concept that refers to a group of CSI-RS resource sets having similar transmission characteristics. A CSI-RS Resource Set Group may be used to optimize transmission efficiency and reduce the overhead associated with individualized control signaling. A CSI-RS Resource Set Group enables the base station to transmit a single CSI-RS resource set for multiple antennas or transmission points, thereby reducing the number of control signals required for beamforming and other transmission optimization techniques.

[0051] A CSI-RS Resource Set Group is characterized by a unique identifier known as the CSI-RS Configuration Index (CRI). The CRI is used by the UE to identify the CSI-RS Resource Set Group and associated communication characteristics. A CSI-RS Resource Set Group can be used for various transmission parameters, including beamforming, channel quality measurement, and handover.

[0052] <CSI Reporting> CSI reporting, for example in LTE or 5G NR, is a mechanism by which a UE can provide feedback to a base station about the quality of the radio channel. To this end, the UE estimates the channel quality based on reference signals transmitted by the base station and reports this information to the base station.

[0053] CSI reporting in 5G NR is more advanced than CSI reporting in LTE and includes various feedback types and reporting configurations. UEs estimate channel quality based on reference signals transmitted by the base station, including CSI-RS and Demodulation Reference Signals (DMRS). The UE then reports this information to the base station using one or more feedback types, such as:

[0054] Periodic CSI feedback: The UE transmits CSI feedback at regular intervals and offsets specified by the base station.

[0055] - Aperiodic CSI feedback: The UE sends CSI feedback when triggered by the base station.

[0056] - Semi-persistent CSI feedback: The UE periodically transmits CSI feedback with a periodicity and a certain offset set by the base station, which may be triggered or stopped by the base station, allowing the base station to anticipate when the feedback will be received.

[0057] The feedback type can be configured with different reporting settings, including the number of bits used to encode the feedback, the frequency of the feedback report, and the aggregation of multiple subcarriers or antennas.

[0058] The base station may use the CSI feedback to adapt transmission parameters, such as modulation and coding schemes, to the current channel conditions. CSI reporting is a mechanism for achieving high data rates and efficient use of the radio spectrum in 5G NR.

[0059] <Power loss estimation> Power loss estimation in 5G NR refers to the mechanism by which a UE estimates the power loss in the radio channel between the UE and a base station. This estimation is important for determining the appropriate transmit power level to achieve the desired quality of service and minimize interference.

[0060] The UE estimates the power loss based on reference signals transmitted by the base station, such as the CSI-RS, which are typically performed using a Channel Quality Indicator (CQI), which provides information about the quality of the channel, or a Reference Signal Received Power (RSRP), which provides information about the received signal strength.

[0061] The power loss estimate may be used by the UE to adjust the transmit power level and improve the quality of the received signal. The UE may use different power levels for different transmit or antenna ports depending on the estimated power loss.

[0062] The base station can also use the power loss estimate to adjust transmission parameters, such as beamforming vectors, to improve the quality of the transmitted signal and reduce interference.

[0063] Power loss estimation is a key aspect of wireless communication systems such as LTE and 5G NR, as it enables efficient use of the radio spectrum and improved quality of service for users.

[0064] <Uplink power control> Uplink power control refers to the process of adjusting the transmit power of a UE in the uplink direction so that the signal received by the base station is neither too weak nor too strong. Uplink power control is performed to ensure efficient use of radio resources and maintain a target quality of service (QoS) for the UE. Power control can be either open-loop or closed-loop.

[0065] In open-loop power control, the UE adjusts its transmit power based on a power control offset without any feedback from the base station. In closed-loop power control, the base station provides feedback to the UE to more accurately adjust the transmit power based on channel conditions. The closed-loop power control mechanism may be based on channel quality indicator (CQI) feedback from the base station. The UE adjusts its transmit power using the CQI to maintain a target signal-to-noise ratio (SNR) at the base station. CQI feedback is typically sent periodically from the base station to the UE, and the UE adjusts its transmit power based on the latest CQI value.

[0066] <Downlink Control Information (DCI)> DCI (Downlink Control Information) is a message sent by a base station to a UE on a Physical Downlink Control Channel (PDCCH) to carry downlink control information. DCI provides the UE with information about modulation and coding schemes, resource allocation, power control, and other transmission parameters that the UE needs to decode received data.

[0067] The DCI format is defined by the 5G NR standard and consists of several fields that carry specific information, including:

[0068] - Format indicator (FI): Indicates the format of the DCI.

[0069] - Resource indicator (RI): Indicates resource allocation such as time-frequency resources, antenna ports, and precoding information.

[0070] - Modulation and coding scheme (MCS): Indicates the modulation method and coding rate used for transmission.

[0071] - New data indicator (NDI): Indicates whether the transmission carries new data or retransmitted data.

[0072] - Hybrid Automatic Repeat Request (HARQ) process number: indicates the HARQ process number used for transmission.

[0073] - Power Control Command (PUCCH / PUSCH): Indicates the power control command for uplink or downlink transmission.

[0074] - Scheduling assignment: indicates the scheduling assignment for the UE, including time-frequency resources, modulation and coding schemes, as well as other transmission parameters.

[0075] - Scheduling request (SR): indicates a scheduling request for a UE to request uplink resources.

[0076] DCI can have different formats and settings according to specific use cases and available radio resources. The base station uses DCI to control downlink transmission and allocate resources to the UE. The UE uses the information in DCI to configure its receiver and process the received data.

[0077] DCI is transmitted in a dynamic and flexible manner, enabling efficient use of the radio spectrum and supporting various use cases and services. The base station can use different DCI formats and settings to support services such as enhanced Mobile Broadband (eMBB), Ultra-Reliable Low-Latency Communications (URLLC), and massive Machine Type Communications (mMTC).

[0078] <UE-specific DCI> UE-specific DCI is a type of DCI message transmitted by the base station to a specific UE to control downlink transmission for each UE. UE-specific DCI contains information specific to a particular UE, such as its identification, the number of allocated resource blocks, and the modulation and coding scheme used.

[0079] UE-specific DCI is transmitted on the Physical Downlink Control Channel (PDCCH) and contains information regarding modulation and coding scheme, resource allocation, power control, and other transmission parameters. The UE uses the information in UE-specific DCI to configure its receiver and process the received data.

[0080] The UE-specific DCI format includes a UE identity that identifies the UE that is the target of the DCI message, and the UE identity is used by the UE to determine whether it is the target of the DCI message.

[0081] Using UE-specific DCI is particularly beneficial when UEs have different transmission requirements, such as in a mixed-service environment where different UEs may have different quality-of-service (QoS) requirements.

[0082] UE-specific DCI may enable efficient and reliable communication for each UE and may also enable the base station to control downlink transmission for individual UEs, taking into account the specific transmission parameters and interference conditions in the cell, thereby ensuring that each UE receives an optimal signal and maximizing the efficiency of downlink transmission.

[0083] <Group-common DCI> Group-common DCI is a type of DCI message transmitted by a base station to a group of UEs that share the same set of transmission parameters. Group-common DCI is used to optimize transmission efficiency and reduce overhead associated with personalized control signaling.

[0084] Group-wide DCI may convey the same set of transmission parameters to a group of UEs, allowing the group of UEs to use the same transmission configuration for data reception, thereby reducing the overhead associated with personalized signaling, as the base station only needs to send one DCI message to control transmission for the group of UEs.

[0085] The group common DCI format may include a group identifier (GID) that is used to identify a group of UEs that share the same transmission parameters. The GID is used by the UE to determine whether a DCI message is intended for the UE.

[0086] The use of group-common DCI is particularly beneficial when a large number of UEs share the same transmission parameters, such as in multicast and broadcast scenarios. Therefore, the use of group-common DCI enables efficient and scalable control signaling for various use cases and services. The use of group-common DCI reduces signaling overhead and enables a base station to efficiently control downlink transmissions for a group of UEs with the same transmission parameters.

[0087] <Cell-specific DCI> Cell-specific DCI is a type of DCI message sent by a base station to a UE to control downlink transmissions on a cell-by-cell basis. Cell-specific DCI contains information specific to a particular cell, such as physical cell identity (PCI), frequency, and reference signal configuration.

[0088] The cell-specific DCI is transmitted on the Physical Downlink Control Channel (PDCCH) and contains information about modulation and coding schemes, resource allocation, power control, and other transmission parameters. The UE uses the information in the cell-specific DCI to configure its receiver and process the received data.

[0089] The cell-specific DCI format includes a cell identity (ID) that identifies the cell that is the target of the DCI message. The cell ID is used by the UE to determine whether it is the target of the DCI message.

[0090] Using cell-specific DCI is particularly beneficial when UEs are located close to each other and may receive signals from multiple cells. Cell-specific DCI may enable efficient and reliable communication on a cell-by-cell basis. Cell-specific DCI may enable a base station to control downlink transmissions for UEs taking into account specific transmission parameters and interference conditions in the cell. This ensures that each UE receives an optimal signal and maximizes the efficiency of downlink transmissions.

[0091] <Antenna port> An antenna port refers to a logical antenna (antenna group) formed from one or more physical antennas. That is, an antenna port does not necessarily refer to one physical antenna, but may refer to an array antenna consisting of multiple antennas. For example, the number of physical antennas constituting an antenna port is not defined. Instead, an antenna port is defined as the smallest unit through which a terminal is permitted to transmit a reference signal. An antenna port can also be defined as the smallest unit for multiplication of precoding vector weights.

[0092] <Beamforming> Beamforming enables directional transmission of data between a base station and a UE. Beamforming allows the base station to focus its transmission energy in the direction of the UE, thereby improving signal quality and overall system performance.

[0093] In 5G NR, beamforming is achieved using advanced signal processing techniques such as precoding and MIMO (Multiple-Input Multiple-Output). Precoding is used to optimize the transmitted signal by adjusting the signal amplitude and phase to maximize signal strength in the direction of the UE. MIMO is used to enhance signal quality by using multiple antennas at the base station and UE, enabling spatial multiplexing and diversity.

[0094] Beamforming can be achieved using two main techniques: analog beamforming and digital beamforming. Analog beamforming is performed in the RF (Radio Frequency) domain and involves adjusting the phase and amplitude of the signal at the antenna level. Digital beamforming is performed in the baseband domain and involves digitally processing the signal before it is sent to the antenna.

[0095] <Digital beamforming> Digital beamforming is a technique used to direct the transmission of data between a base station and a UE in a specific direction. Digital beamforming is performed in the baseband domain and involves digitally processing the signal before it is transmitted to the antenna.

[0096] Digital beamforming involves three main steps: channel estimation, precoding, and power amplification. Channel estimation is performed to determine the channel response between the base station and the UE. Then, precoding is applied to optimize the transmitted signal by adjusting the signal amplitude and phase to maximize the signal strength in the direction of the UE. Finally, the precoded signal is amplified and transmitted to the antenna.

[0097] One advantage of digital beamforming is that it allows for more precise control of the transmitted signal, as the signal can be tailored and optimized based on channel conditions and the UE's location, improving signal quality and overall system performance.

[0098] Another benefit of digital beamforming is that it enables the efficient use of MIMO (Multiple-Input Multiple-Output) technology. MIMO involves using multiple antennas at the base station and UE to improve signal quality through spatial multiplexing and diversity. Digital beamforming allows the base station to optimize transmissions to the UE based on channel conditions and the UE's location, thereby improving overall system performance and enabling new use cases and services.

[0099] Figure 6a is a schematic diagram illustrating the principle of digital beamforming for CSI-RS transmission. A complex-valued CSR-RS sequence is provided to each of multiple baseband phase shifters and multiple downstream power amplifiers (PAs). The base station adjusts the phase and amplitude of the signal at each antenna to create a directional beam focused on the UE. The complex signal processing required for digital beamforming is typically performed using advanced signal processing algorithms, such as beamforming algorithms designed to optimize signal quality. The phase-shifted and amplified signals are then directed to the antenna elements to form the precoded / beamformed CSI-RS.

[0100] <Analog beamforming> Analog beamforming involves the use of an array of antennas at a base station that can be used to create a directional beam focused on the UE. By adjusting the phase and amplitude of the signal at each antenna, the beam can be steered in a specific direction. This allows the base station to direct its transmitted energy towards the UE.

[0101] One advantage of analog beamforming is that it is a simpler and more cost-effective approach than digital beamforming: it does not require complex signal processing and can be implemented using relatively simple hardware.

[0102] However, analog beamforming has some limitations compared to digital beamforming. For example, analog beamforming cannot adjust the transmitted signal based on the channel conditions and the UE's location, making it less flexible and accurate than digital beamforming. Furthermore, analog beamforming cannot fully utilize the spatial diversity provided by MIMO (Multiple-Input Multiple-Output), making it less efficient than digital beamforming when using MIMO technology.

[0103] Figure 6b is a schematic diagram illustrating the principle of analog beamforming for CSI-RS transmission. In contrast to the digital beamforming approach shown in Figure 6a, a baseband signal is fed to a power amplifier (PA). The resulting amplified signal output by the PA is fed to multiple analog phase shifters, each connected to a respective antenna element. That is, in analog beamforming, the base station adjusts the phase of the signal at each antenna to create a directional beam focused on the UE. This is done by using phase shifters, which are passive components that introduce a phase delay into the signal path.

[0104] <Quasi-Colocation (QCL)> Quasi-colocated (QCL) refers to the situation where multiple antennas or transmission points are located close enough to each other that their channel responses are similar. Two antenna ports are said to be quasi-colocated (QCLed) if the characteristics of the channel through which symbols on one antenna port are carried can be inferred from the channel through which symbols on the other antenna port are carried.

[0105] QCL may be used to optimize beamforming and precoding by reducing signaling overhead and transmission optimization complexity. By grouping together antennas or transmission points that are close enough to each other to have similar channel responses, the base station can use the same beamforming and precoding weights for all antennas in the group, thereby simplifying the transmission optimization process.

[0106] QCL can be applied to various transmission scenarios including multi - user MIMO (Multiple - Input Multiple - Output) and beamforming. In multi - user MIMO, QCL can be used to group together the antennas or transmission points of multiple UEs located close to each other, thereby simplifying transmission optimization and potentially improving overall system performance.

[0107] <TCI state> The TCI (Transmission Configuration Indication) state refers to the way in which a UE is configured to receive data from a base station using a specific resource allocation pattern. The TCI state is signaled to the UE by the base station via DCI.

[0108] [[ID=1'4]]The TCI state is used to optimize the transmission of data to the UE by adjusting the resource allocation pattern based on the channel conditions and the UE's location. The TCI state determines the resource allocation pattern for different types of data and how the resource allocation patterns for different types of data are transmitted to the UE. This helps to maximize signal quality and overall system performance. <U

[0109] The base station determines the appropriate TCI state to use based on the channel conditions and the location of the UE, and the TCI state is signaled to the UE via DCI to configure the UE to receive data using the appropriate resource allocation pattern.

[0110] The TCI states may be dynamically transmitted in DCI messages that contain settings such as the QCL relationship between DL RSs and PDSCH DMRS ports in one CSI-RS set. A UE can be configured with a list of TCI state settings, where each TCI state contains parameters for setting a quasi-co-location relationship between one or two downlink reference signals, DM-RS ports of the PDSCH, DM-RS ports of the PDCCH, or CSI-RS ports of CSI-RS resources.

[0111] <Synchronization and Synchronization Signal Block (SSB)> In NR downlink synchronization, the UE detects radio boundaries (i.e., when a radio frame starts) and OFDM symbol boundaries (i.e., when an OFDM symbol starts). This is performed by detecting and analyzing synchronization signal blocks (SSBs). SSB components include synchronization signals: primary synchronization signals (PSSs) and secondary synchronization signals (SSSs). NR SSBs may be transmitted in a variety of different patterns depending on the numerology and several other parameters. The patterns are signaled in the system information.

[0112] In NR, the TRS may be provided as a dedicated RS to a UE or as a common RS for multiple UEs in connected mode, and based on the TRS, the UE may be able to fine-tune synchronization without having to constantly receive a synchronization signal.

[0113] In some systems, such as NR (e.g., Rel. 15 / 16), TRS / CSI resources are configured for UEs in RRC_CONNECTED mode to be utilized, for example, in measurements for channel state estimation, time tracking, frequency tracking, and / or beam tracking. For UEs in other modes, such as RRC_IDLE and RRC_INACTIVE, such measurements may rely on SSBs. For Rel. 17 NR, TRS / CSI-RS may also be used by some INACTIVE / IDLE UEs for time and frequency tracking, supporting this feature of additional TRS / CSI-RS opportunities signaled to these UEs. Thus, in general, TRS / CSI and SSBs are signals that can be used by UEs in any RRC state for channel state estimation, time tracking (e.g., time synchronization), frequency tracking, and / or beam tracking.

[0114] In general, an SSB may be transmitted in a specific (spatial) direction, in which case the SSB may be referred to as an "SSB beam." In particular, each SSB / SSB beam may also have and / or indicate a beam index (also known as an SSB index) that can be used to distinguish the SSB beam from other SSB beams transmitted in directions other than the SSB beam. The UE may then determine the SSB index of the received SSB beam based on the received signal of the SSB beam and determine the direction from which the received SSB beam was transmitted by the base station.

[0115] In general, the current SSB structure and signaling in SIB1 may be used by the base station to indicate to the UE which SSB beams it is using, and the base station may use the ON / OFF indication to inform the UE which beams should be switched ON or OFF during which time periods.

[0116] <Network energy saving> Procedures related to CSI and beam management can be used to optimize the use of network resources, reduce energy consumption, and improve the overall performance of the network. These procedures may include measurements, reporting, and signaling to enable efficient adaptation of spatial elements such as antenna ports or active transceiver chains. By implementing these procedures, the network may achieve a better balance between performance and energy consumption.

[0117] To save network energy, there are operational options that facilitate spatial element adaptation. In other words, the number of active amplifiers used for an antenna port may be adapted. This approach can result in antennas, RS ports, or beams being switched ON or OFF. In particular, in analog beamforming, as shown in Figure 6b, if the PA is switched OFF, the RS port / beam is switched OFF and the respective signaling is not transmitted. In digital beamforming, as shown in Figure 6a, antenna element adaptation can result in the adaptation of the beam power level of the respective antenna / RS port.

[0118] Additionally, to save network energy, the output power level of each PA may be adapted, which may result in adapting / reducing the power level of each antenna / RS port or beam in digital beamforming as well as analog beamforming.

[0119] In general, the base station may decide to reduce the power level of an antenna / RS port or beam depending on the number of UEs being served, e.g., the power level may be reduced the more UEs are served by the base station.

[0120] However, adapting spatial elements such as ports, transmit / receive chains, and PAs can result in several drawbacks. For example, if the UE reports CSI without L1-RSRP / SINR, the number of CSI-RS ports and other settings, such as the codebook for PMI used for CSI measurement and reporting, may change. Furthermore, changes in the number of CSI-RS ports may occur in the case of digital beamforming with flexible antenna virtualization and in the case of analog beamforming.

[0121] Furthermore, if the CSI reporting includes L1-RSRP / SINR and beam management procedures, adapting the spatial elements may result in changes to the beams measured and reported by the UE.

[0122] Furthermore, for digital beamforming, a change in the number of amplifiers and / or spatial elements used will result in a different power level being used for each beam port as a reference, which is reflected by the EPRE of the CSI-RS. Thus, spatial element adaptation may result in different path loss estimates being performed by the UE.

[0123] Furthermore, the valid TCI state list may be changed for spatial element adaptation. In particular, if a downlink (DL) TCI state is associated with a configured SSB beam index or CSI-RS resource as a QCL reference, adapting the number of active amplifiers and / or antenna elements will affect the total number of beams and the configuration of CSI-RS resources, ultimately resulting in a change in the valid TCI state list.

[0124] When adapting the transmit (Tx) power of the CSI-RS, the change in the offset between the power of the CSI-RS and the power of the SSS may affect the path loss calculation performed by the UE when the UE uses the CSI-RS as a reference. Additionally, the CQI calculation may be affected by the change in the power offset between the CSI-RS and the PDSCH.

[0125] That is, in summary, if the presence and / or power level of the CSI-RS changes dynamically, the UE's procedures using the CSI-RS as a reference may be affected.

[0126] <Embodiment> The following describes UEs, base stations, and procedures for new radio access technologies assumed in 5G mobile communication systems, but these may also be used in LTE mobile communication systems. Various implementations and variations are also described. The following disclosure is facilitated by, and may be based, for example, at least in part on, the above discussion and findings.

[0127] In general, it should be noted that many assumptions have been made herein so as to be able to explain the principles underlying the present disclosure in a clear and understandable manner, but it should be understood that these assumptions are merely examples made herein for the purpose of explanation and are not intended to limit the scope of the present disclosure.

[0128] Furthermore, although specific terminology used in the context of new radio access technologies for upcoming 3GPP 5G communication systems has not yet been fully determined or may ultimately change, some of the terms used below, such as procedures, entities, and layers, are closely related to the terms used in LTE / LTE-A systems or in current 3GPP 5G standardization. Therefore, the terms may change in the future without affecting the functionality of the embodiments. Therefore, those skilled in the art will recognize that the embodiments and their scope of protection are not limited to the specific terms illustratively used herein due to the absence of newer or ultimately agreed-upon terminology, but should be understood more broadly in terms of the functions and concepts underlying the functions and principles of the present disclosure.

[0129] For example, a mobile station, mobile node, user terminal, or user equipment (UE) is a physical entity (physical node) in a communication network. A node may have several functional entities. A functional entity refers to a software or hardware module that implements and / or provides a given set of functionality to other functional entities of the same node or other nodes or the network. A node may have one or more interfaces that attach the node to a communication facility or medium over which the node can communicate. Similarly, a network entity may have logical interfaces that attach the functional entity to a communication facility or medium over which the functional entity may communicate with other functional entities or corresponding nodes.

[0130] The term "base station" or "radio base station" in this specification refers to a physical entity in a communication network. Similar to a mobile station, a base station may have several functional entities. A functional entity refers to a software or hardware module that implements and / or provides a predetermined set of functions to other functional entities of the same node or other nodes or networks. A physical entity performs several control tasks for communication devices, including one or more of scheduling and configuration. It should be noted that base station functions and communication device functions may also be integrated within a single device. For example, a mobile terminal may also implement base station functions for other terminals. The term used in LTE is eNB (or eNodeB), while the term currently used in 5G NR is gNB.

[0131] The communication between the UE and the base station is typically standardized and may be defined by different layers such as PHY, MAC, RRC, etc. (see background discussion above).

[0132] The present disclosure relates to a UE, a base station, a UE method, and a base station method that address issues related to energy saving in a network through spatial element adaptation or transmit power adaptation performed by the base station.

[0133] FIG. 7 shows a general and simplified exemplary block diagram of a user equipment 100 (also referred to as a communication device) and a base station 200, which is illustratively assumed herein to be a scheduling device such as an eNB or gNB (network node). However, in general, the scheduling device may also be a terminal in the case of a sidelink connection between two terminals. Furthermore, particularly with regard to URLLC, eMBB, and mMTC use cases, the communication device 100 may also be a sensor device, a wearable device, a connected vehicle, or a controller for an automated machine in an industrial factory. The communication device 100 may also be capable of functioning as a relay between a base station and other communication devices (e.g., the present disclosure is not limited to communication “terminals” or user “terminals”).

[0134] The UE 100 and the base station 200 (eNB / gNB) communicate with each other via a (wireless) physical channel 300 using their respective transceiver units 110 (on the UE 100 side) and 210 (on the base station 200 side). The base station 200 and the UE 100 together form a communication system 10. The communication system 10 may further include other entities in addition to those shown in FIG. 1 .

[0135] The UE 100 may include a transceiver 110 and a (processing) circuit 120, and the scheduling device 200 may include a transceiver 210 and a (processing) circuit 220. The transceivers 110, 210 may include and / or function as a receiver and / or a transmitter. In other words, in this disclosure, the term “transceiver” is used for hardware and software components that enable the UE 100 or the base station 200, respectively, to transmit and / or receive wireless signals over the wireless channel 300. Thus, a transceiver corresponds to a receiver, a transmitter, or a combination of a receiver and a transmitter. Typically, it is assumed that the base station and the UE can both transmit and receive wireless signals. However, for some applications, particularly eMBB, mMTC, and URLLC (smart home, smart city, industrial automation, etc.), devices such as sensors may only receive signals. Furthermore, the term “circuit” includes processing circuits formed by one or more processors or processing units, etc.

[0136] As shown in FIG. 7, in some embodiments, a user equipment (UE) 100 comprises a transceiver 110 that, in operation, receives a power level indicator from a base station, the power level indicator indicating a power level of a Channel State Information-Reference Signal (CSI-RS) resource and / or whether the CSI-RS resource is transmitted by the base station; and a circuit 120 that, in operation, operates in response to the power level and / or whether the CSI-RS resource is transmitted by the base station 200.

[0137] 8a shows the functional structure of the circuit 120. In particular, the circuit 120 includes a Tx / Rx control circuit 121. In operation, the Tx / Rx control circuit 121 controls the transceiver unit 110. For example, controlling the transceiver unit 110 may include controlling the transceiver unit 110 to receive (detect) signaling transmitted by the base station 200, including a power level indicator. In particular, the Tx / Rx control circuit 121 may control the transceiver unit 110 to decode the power level indicator. The circuit 120 may include an operation processing circuit 122 that operates depending on the power level and / or whether CSI-RS resources are transmitted by the base station 200.

[0138] 7, in some embodiments, base station 200 comprises circuitry 220. Circuitry 220, upon operation, determines that signaling including an availability indication is to be generated. Circuitry 220, upon operation, determines a power level of a Channel State Information-Reference Signal (CSI-RS) resource and / or whether the CSI-RS resource is to be transmitted by the base station. Furthermore, circuitry 220, upon operation, generates signaling including a power level indicator indicating the power level of the CSI-RS resource and / or whether the CSI-RS resource is to be transmitted by base station 200, and transceiver unit 210, upon operation, transmits the generated signaling.

[0139] 8b shows the functional structure of the circuit 220. In particular, the circuit 220 includes a Tx / Rx control circuit 221. In operation, the Tx / Rx control circuit 221 controls the transceiver 210. For example, the control may include controlling the transceiver 210 to transmit a power level indicator to the UE 100. The circuit 220 may include a power level determination processing circuit 222 that determines the power level of a Channel State Information-Reference Signal (CSI-RS) resource and / or whether a CSI-RS resource is to be transmitted by the base station 200. The Tx / Rx control circuit 221 then controls the transceiver 210 to transmit signaling that includes the power level indicator.

[0140] Corresponding to the above-mentioned base station 200, there is provided a communication method performed by the base station 200 (or a scheduling device). As shown in Figure 9, the method includes: (i) a step S200 of determining a power level of a CSI-RS resource and / or whether the CSI-RS resource is transmitted by the base station 200; and (ii) a step S210 of transmitting a power level indicator to the UE 100, the power level indicator indicating a power level of the CSI-RS resource and / or whether the CSI-RS resource is transmitted by the base station.

[0141] Also provided is a communication method performed by the UE 100, corresponding to the above-mentioned UE 100. As shown in Figure 9, the method includes: (i) a step S100 of receiving a power level indicator from the base station 200, the power level indicator indicating a power level of a Channel State Information-Reference Signal (CSI-RS) resource and / or whether the CSI-RS resource is transmitted by the base station 200; and (ii) a step S110 of operating depending on the power level and / or whether the CSI-RS resource is transmitted by the base station 200.

[0142] <Circuit> The circuits 120, 220 (or processing circuits) may be one or more hardware components, such as one or more processors or any LSI. Between the transceiver units 110, 210 and the processing circuits 120, 220, there are input / output points (or nodes) 130, 230. The processing circuits 120, 220 control the transceiver units 110, 210, i.e., control the receiver and / or transmitter, and exchange receive / transmit data. The transceiver units 110, 210 may include, as the transmitter and receiver, one or more antennas, amplifiers, radio frequency (RF) modulators / demodulators, etc. The processing circuitry 120, 220 may perform control tasks such as controlling the transceiver units 110, 210 to transmit user data and control data provided by the processing circuitry 120, 220 and / or receive user data and control data for further processing by the processing circuitry 120, 220. The processing circuitry 120, 220 may also be responsible for performing other processes such as judging, determining, calculating, measuring, etc. The transmitter unit may be responsible for performing the process of transmitting and other processes related thereto. The receiver unit may be responsible for performing the process of receiving and other processes related thereto.

[0143] It should be noted that the circuits 120, 220 may be general processing circuits including one or more processors that may execute code instructions stored in memory (which may be part of the circuits 120, 220) and may include portions of code instructions corresponding to the functions described above for the respective circuits. The functionality may be provided by hardware adaptations and / or software. The present disclosure is not limited to any particular circuitry, and embodiments of the present disclosure may include dedicated or programmable hardware, general-purpose hardware, or any combination thereof.

[0144] It is further noted that any of the steps / operations described below may be performed or controlled by circuit 120 (at UE 100) and / or circuit 220 (at base station 200). Particularly in the further description, unless expressly stated or otherwise indicated by context, details and embodiments apply to UE 100, base station 200, and method, respectively.

[0145] First Embodiment In a first embodiment, the UE 100 comprises a transceiver 110 that, in operation, receives a power level indicator from the base station 200, the power level indicator indicating a power level of a Channel State Information-Reference Signal (CSI-RS) resource and / or whether the CSI-RS resource is transmitted by the base station 200. The UE 100 further comprises, in operation, a circuit 120 that operates depending on the power level and / or whether the CSI-RS resource is transmitted by the base station 200. In particular, the power level represents a power offset between the transmit power of the CSI-RS and the transmit power of a synchronization signal.

[0146] Hereinafter, the power offset between the transmission power of the CSI-RS and the transmission power of the synchronization signal is referred to as the first power offset. The indication of whether the CSI-RS resource is transmitted by base station 200 is also referred to as the CSI-RS resource ON / OFF indication. That is, the power level indicator may indicate the first power offset and / or the CSI-RS resource ON / OFF indication. The power level indicator does not need to directly indicate the power level / CSI-RS resource ON / OFF indication, but may represent a value associated with a (predetermined or configured) first power offset value or power offset resource ON / OFF indication.

[0147] That is, the UE 100 is provided with information regarding the difference (first power offset) between the transmit power of the CSI-RS and the synchronization signal, which may be SSS. The transmit power may be the power used to transmit each radio signal from the base station 200 to the UE 100. The transmit power may be measured in watts (W), decibels (dB), or other suitable units. The power of each signal received by the UE 100 is referred to as the received power.

[0148] The power level indicator indicates the offset (difference) between the transmit power of the CSI-RS and the transmit power of the SSS, and may be measured in W, dB, etc.

[0149] For example, each of the one or more CSI-RS resource sets may be associated with a power level and / or with whether the respective CSI-RS resource is transmitted (CSI-RS resource ON / OFF indication). In operation, the transceiver 110 receives, as a power level indicator, a CSI-RS resource set indicator that indicates the CSI-RS resource set.

[0150] In the first embodiment, the UE 100 receives the power level indicator via a group-common DCI, but the present disclosure is not limited thereto, and the power level indicator may be received via a UE-specific DCI, a group-common DCI, or a MAC control element (MAC CE).

[0151] The UE 100 is configured with one or more starting positions of one or more blocks in the DCI and / or one or more indices of the blocks. The power level indicators are received via the DCI according to the starting positions of the blocks and / or one or more indices of the blocks. In each block, the number of CSI-RS resource set groups, the group ID for each CSI-RS resource set, and the bit width of the indication of each group are RRC configurable.

[0152] 10 is a schematic diagram illustrating an example of signaling a power level indicator via group-wide DCI. A UE is configured with a correspondence between one or more CSI-RS resource set groups and one or more respective first power offsets and / or CSI-RS resource ON / OFF indications. In other words, each CSI-RS resource set group is associated with a first power offset and / or whether the CSI-RS resource is transmitted by the base station. The correspondence may be, for example, fixed or RRC-configured.

[0153] That is, for each indication field of each block and each CSI-RS resource set group, the candidate value of the CSI-RS resource ON / OFF indication and / or first power offset selected or indicated by the DCI may be fixed or may be RRC configured.

[0154] In one example, a first offset value of minus infinity (-∞), expressed in dB, indicates that the PA / element is switched OFF, which corresponds to an amplifier or antenna element being turned off and, in the case of analog beamforming, a transmit / receive point (TRP) level of zero. In other words, a power level of minus infinity may indicate that no CSI-RS resources are transmitted by the base station. Further, candidate values ​​for the first power offset may include -3 dB, -6 dB, -9 dB, etc. The above values ​​may represent a reduction in amplifier power or muting / turning OFF of a power amplifier by half, three-quarters, or seven-eighths, respectively.

[0155] The power level indicator may indicate the first offset as a relative offset value or an absolute offset value. That is, if the power level indicator indicates the first power offset relatively, the UE 100 may determine the first offset by adding the first offset indicated by the power level indicator to an already configured power level or EPRE (Energy Per Resource Element) (e.g., as configured by RRC). That is, the power level indicator may indicate the first power offset with respect to the already configured power level or EPRE. On the other hand, the power level indicator may indicate the first power offset in an absolute manner independent of the already configured power level / EPRE.

[0156] Furthermore, the UE 100 may determine the first power offset in an open-loop (non-accumulative) manner or in a closed-loop (accumulative) manner. That is, when multiple power level indicators (e.g., a first power level indicator and a second power level indicator) are received by the UE 100, the first power offset may be determined by applying the power level indicators independently of each other in a relative manner as described above or in an absolute manner. On the other hand, the UE 100 may determine the first power offset in an accumulated manner, where the second power level indicator (received after the first power level indicator) is applied to the first power offset previously determined using the first power level indicator.

[0157] In the signaling scheme shown in FIG. 10 , the UE 100 receives a power level indicator via a group-common DCI, and the UE 100 is configured with one or more starting positions of a block in a DCI field or one or more indices of a block. That is, the power level indicator is received via the group-common DCI according to the configured starting positions / block indices. One field of a block may be configured to be the same for multiple UEs 100, so that the same CSI-RS is received by the UEs. Therefore, the power level indicator may be signaled to multiple UEs 100 using the group-common DCI. Furthermore, the UE 100 may be configured with multiple blocks corresponding to multiple CSI-RS receptions.

[0158] <First Modification> In a first variant, circuit 120, in operation, determines whether the first power offset is a first value and / or whether the CSI-RS resource is indicated as not being transmitted by base station 200. In other words, circuit 120 determines whether the power level indicated by the power level indicator is a first value or whether the CSI-RS resource ON / OFF indication indicates that the CSI-RS resource is not transmitted by base station 200 (CSI-RS resource OFF). Furthermore, circuit 120 determines whether the CSI-RS is configured with a TCI state setting. In other words, circuit 120 may determine whether the power level of the CSI-RS resource / CSI-RS resource ON / OFF indication indicated by the power level indicator is associated with a TCI state.

[0159] If the first power offset is the first value and / or the power level indicator indicates CSI-RS resources OFF, the TCI state associated with the CSI-RS is not expected to be activated or indicated in the DCI. If the TCI state is already activated, circuit 120 may deactivate the TCI state.

[0160] The first value may be a value associated with CSI-RS resources OFF, for example, zero W or minus infinity dB, but is not limited to the above values ​​and may be, for example, a predetermined or pre-configured value.

[0161] In other words, if a TCI state is configured in the RRC configuration where a first power offset of a certain CSI-RS resource indicates a first value, or where a CSI-RS resource is indicated to be OFF and where the CSI-RS resource is used for QCL with other channels (PDCCH / PDSCH), the OFF indication / first value does not cause the UE 100 to expect that the TCI state referencing the CSI-RS resource is activated, e.g., by the MAC CE, or indicated in an L1 TCI indication, e.g., in a DCI. Furthermore, if the TCI state is already activated by the MAC CE, the first value / OFF indication causes the UE 100 to deactivate the TCI state referencing the CSI-RS resource.

[0162] Therefore, the interaction of the UE 100 with the TCI framework is consistent with the operations performed by the base station 200.

[0163] <Second Modification> In a second variation, after the transceiver 110 receives the power level indicator, the circuit 120 may perform at least one of the following operations:

[0164] If the first power offset is a first value and / or the CSI-RS resource is indicated as not being transmitted by base station 200, UE 100 may stop reporting CSI according to a CSI reporting configuration associated with the CSI-RS resource.

[0165] That is, when the first power offset of the CSI-RS is a first value, which may be minus infinity, zero, etc., or when a CSI-RS resource OFF indication is received (i.e., when the CSI-RS resource is not transmitted by base station 200), UE 100 does not perform CSI reporting for the CSI-RS. Therefore, the behavior of UE 100 is adapted to take into account the energy saving measures performed by base station 200. Specifically, when the CSI-RS resource is not transmitted by base station 200, UE 100 does not perform the respective CSI-RS reporting. This may further lead to a reduction in energy consumption on the UE side.

[0166] If the first power offset of the CSI-RS is a value other than the first value and / or the power level indicator indicates that the CSI-RS resource is to be transmitted by base station 200 (e.g., a CSI-RS resource ON indication is received) and the CSI-RS resource is part of a CSI reporting configuration, UE 100 starts reporting CSI associated with the CSI reporting configuration when the CSI-RS resource (indicated by the power level indicator that is a CSI-RS resource ON indication) is switched from OFF to ON, or continues reporting CSI. This approach ensures that the behavior of UE 100 is consistent with the power saving procedure performed by base station 200. In particular, it can be ensured that the required CSI reporting is provided to base station 200 by UE 100.

[0167] When UE 100 is configured with multiple sets of CSI reporting configurations, UE 100 may switch between the multiple CSI reporting configuration sets. The switching may be based on a CSI-RS resource set group index indicated as ON (by a power level indicator indicating that CSI-RS resources are transmitted by base station 200, i.e., a CSI-RS resource ON indication) and / or a first power offset other than a first value (e.g., other than minus infinity or zero). The multiple CSI configurations may be associated with reported values, i.e., for example, LI, CQI, RI, PMI, L1-RSRP and / or L1-SINR, and optionally a codebook for PMI.

[0168] The number and / or size of CSI reports transmitted by UE 100 may be semi-static or dynamic. In the semi-static case, the UE reports CSI based only on a fixed or configured set of CSI reporting configurations or a fixed or configured number of CSI reporting configurations. That is, the size of the CSI report is kept consistent between base station 200 and UE 100. In the dynamic case, the UE adjusts the size of the CSI report based on the CSI-RS indicated to be ON (by a power level indicator, which is a CSI-RS resource ON indication) or the number of CSI-RS resource set groups indicated to be ON.

[0169] <Third Modification> In a third variant, the circuit 120 operates depending on the power level and / or whether CSI-RS resources are transmitted by the base station in a finite period of time after receiving the power level indicator.

[0170] In other words, the first offset and / or CSI-RS resource ON / OFF indication applies for a finite period of time starting at a certain time after the power level indicator is received. For example, the indication may start applying a fixed or RRC / SIB-configured period of time after the slot in which the UE 100 received the power level indicator. The duration of the finite period may be fixed or RRC / SIB-configured, for example.

[0171] That is, any operation performed by UE 100 that is triggered by or dependent on the power level indicator may be performed only during a certain period. For example, in view of the second variant described above, UE 100 may not perform CSI reporting if a CSI-RS resource OFF indication is received only during the above-mentioned period. However, the present disclosure is not limited to not performing CSI reporting during a period according to an indication of the power level indicator, and any procedure dependent on the power level indicator described above may be performed.

[0172] The period may be set / defined by a first time that is started upon receipt of the power level indicator. After the first time expires, the UE 100 may start a second timer with a runtime equal to the duration of the period. That is, the period is set as the period during which the second timer is running and has not expired.

[0173] FIG. 11 is a flowchart illustrating exemplary steps performed by UE 100, where circuit 120 operates depending on the power level and / or whether CSI-RS resources are transmitted by the base station for a finite period of time after receipt of the power level indicator.

[0174] In step S300, the UE receives a power level indicator from base station 200. The power level indicator indicates a power offset of the CSI-RS resources and / or whether the CSI-RS is transmitted by base station 200 (i.e., a CSI-RS resource ON / OFF indication). The power offset may be a first power offset and / or a second power offset, which will be described further below. In step S310, circuit 120 determines whether the current time is after the application time and within the validity period. The application time is the time from the reception of the power level indicator and indicates the time of the start of the period, i.e., the validity period. If the current time is within the validity period (yes in step S310), the method proceeds to step S320. In step S320, the indicated power offset and / or the indicated CSI-RS resource ON / OFF indication are applied in one or more of the TCI framework, CSI measurement and reporting, and / or path loss estimation and uplink power control, as described above. If the current time is after the application time and not within the validity period (no in step S310), the method proceeds to step S330. In step S330, the UE 100 stops applying the power offset and / or CSR-RS resource ON / OFF indication. Instead, the UE 100 applies whatever was configured before receiving the power level indicator.

[0175] This approach allows the actions performed by the UE 100 to be limited to a specific time period, so that no further instructions to, for example, continue / start CSI reporting need to be sent by the base station 200.

[0176] <Fourth Modification> In a fourth variant, the transceiver 110, during operation, receives a CSI-RS resource. The circuit 120, during operation, calculates a path loss estimate using a first power offset and the received power of the CSI-RS resource. Furthermore, the circuit 120, during operation, performs uplink power control in response to the calculated path loss estimate.

[0177] In particular, the resulting path loss estimate may be used in uplink power control of one or more of the physical uplink shared channel (PUSCH), the physical uplink control channel (PUCCH), the sounding reference signal (SRS), and / or the physical random access channel (PRACH).

[0178] In this manner, the UE may reduce its energy consumption because it may perform the uplink transmission using reduced transmit power.

[0179] <Second embodiment> In a second embodiment, the UE 100 comprises a transceiver 110 that, in operation, receives a power level indicator from the base station 200, the power level indicator indicating a power level of a Channel State Information-Reference Signal (CSI-RS) resource and / or indicating whether the CSI-RS resource is transmitted by the base station 200. The UE 100 further comprises, in operation, a circuit 120 that operates depending on the power level and / or depending on whether the CSI-RS resource is transmitted by the base station. In particular, the power level represents a power offset between the transmit power of the CSI-RS resource and the transmit power of a physical downlink shared channel (PDSCH).

[0180] Hereinafter, the power offset between the transmit power of CSI-RS and the transmit power of PDSCH is referred to as the second power offset. The indication of whether a CSI-RS resource is transmitted by base station 200 is also referred to as a CSI-RS resource ON / OFF indication. That is, the power level indicator may indicate the second power offset and / or the CSI-RS resource ON / OFF indication. The power level indicator does not need to directly indicate the power level / CSI-RS resource ON / OFF indication, but may represent a (predetermined or configured) second power offset value or a value associated with the power offset resource ON / OFF indication.

[0181] That is, the UE 100 is provided with information regarding the difference between the transmit power of the CSI-RS and the PDSCH (second power offset). As in the first embodiment, the transmit power may be the power used to transmit each radio signal from the base station 200 to the UE 100. The transmit power may be measured in watts (W), decibels (dB), or other suitable units. The power of each signal received by the UE 100 is referred to as the received power.

[0182] The power level indicator indicates the offset (difference) between the transmission power of the CSI-RS and the transmission power of the PDSCH, and may be measured using W, dB, or the like.

[0183] In the second embodiment, the power level indicator may be signaled to the UE 100 in the same or similar manner as in the first embodiment, and the power offset indicated by the power level indicator is not related to the first power offset but is related to the second power offset, i.e., the power level indicator may be signaled / transmitted to the UE in the same or similar manner as described above with reference to FIG.

[0184] The second offset may also indicate an offset value as described in the first embodiment. In particular, the second power offset may be indicated as a relative offset or an absolute offset. Furthermore, the power level may be indicated in an open-loop or closed-loop manner.

[0185] However, the second power offset value may be either negative or positive: a negative second power offset value may indicate a power reduction for the CSI-RS resources, whereas a positive second power offset may indicate a power reduction for the PDSCH.

[0186] <Modification> The second embodiment modification is provided according to the first to third modifications of the first embodiment, in which the first power offset is replaced with the second power offset.

[0187] That is, in a variation of the second embodiment corresponding to the first variation of the first embodiment, the circuit 120 may determine whether the second power offset is a first value and / or whether the CSI-RS resources are indicated as not being transmitted and whether the CSI-RS resources are configured with a Transmission Configuration Indication (TCI) state set. If the circuit 120 determines that the second power offset is a first value and / or whether the CSI-RS resources are indicated as not being transmitted and whether the CSI-RS resources are configured with a Transmission Configuration Indication (TCI) state set, the circuit 120 expects the TCI state to be not activated or not indicated in the DCI, or deactivates the TCI state if it is activated.

[0188] Further, in a variant of the second embodiment corresponding to the second variant of the first embodiment, after the transceiver unit 110 receives the power level indicator, the circuit 120 performs at least one of the above-mentioned operations.

[0189] In particular, when the second power offset is the first value and / or the CSI-RS resource is indicated as not being transmitted, circuit 120 may stop reporting CSI according to a CSI reporting configuration associated with the CSI-RS resource.

[0190] Furthermore, if the second power offset is different from the first value and / or the CSI-RS resource is indicated to be transmitted, circuit 120 may start or continue reporting CSI according to a CSI reporting configuration associated with the CSI-RS resource. When performing CSI reporting, UE 100 may take the second power offset value into account when calculating the CSI value. This may be done for any one or any combination of the LI, CQI, PMI, and / or RI. In other words, circuit 120 takes the second power offset into account when determining the above values.

[0191] That is, in other words, if the power level represents a second power offset, i.e., a second power offset between the transmit power of the CSI-RS and the transmit power of the PDSCH, and the circuitry starts or continues reporting the CSI after the transceiver unit 110 receives the power level indicator, the circuitry 120 may, in operation, use the second power offset to determine the value to be included in the CSI.

[0192] Additionally, the circuit 120 may switch between multiple CSI reporting configuration sets based on the power level indicator.

[0193] In a variation of the second embodiment corresponding to the third variation of the first embodiment, the circuit may, in operation, operate depending on the power level and / or depending on whether CSI-RS resources are transmitted by base station 200 in a finite period of time after receipt of the power level indicator.

[0194] <Third embodiment> In the third embodiment, the UE 100 comprises a transceiver 110 that, in operation, receives a power level indicator from the base station 200, the power level indicator indicating a power level of a Channel State Information-Reference Signal (CSI-RS) resource and / or whether the CSI-RS resource is transmitted by the base station 200. The UE 100 further comprises a circuit 120 that, in operation, operates in response to the power level and / or whether the CSI-RS resource is transmitted by the base station 200.

[0195] In particular, the power level may represent a power offset between the transmission power of the CSI-RS resources and the transmission power of the synchronization signal, i.e., a first power offset. Alternatively, the power level may represent a power offset between the transmission power of the CSI-RS resources and the transmission power of the physical downlink shared channel (PDSCH), i.e., a second power offset. Alternatively, the power level may represent the first power offset and the second power offset.

[0196] Furthermore, each of the Transmission Configuration Indication (TCI) states is associated with a power level and / or whether the respective CSI-RS resource is transmitted. In operation, the transceiver 110 receives the TCI state indicators as power level indicators.

[0197] In the third embodiment, the UE 100 receives the power level indicator via a group-common DCI. However, the present disclosure is not limited thereto, and the power level indicator may be received via a UE-specific DCI, a group-common DCI, or a MAC CE.

[0198] As in the first embodiment, the UE 100 is configured with one or more starting positions of one or more blocks in the DCI and / or one or more indices of the blocks. The power level indicators are received via the DCI according to the starting positions of the blocks and / or one or more indices of the blocks. In each block, the number of TCI state groups, the group ID for each CSI-RS resource set, and the bit width of the indication of each group are RRC configurable.

[0199] 12 is a schematic diagram illustrating an example of signaling a power level indicator via a group-wide DCI according to a third embodiment. A UE is configured with a correspondence relationship between one or more TCI state groups and one or more respective first power offsets and / or second power offsets and / or CSI-RS resource ON / OFF instructions. In other words, each TCI state group is associated with a first power offset and / or a second power offset and / or whether a CSI-RS resource is transmitted by base station 200. The correspondence relationship may be, for example, fixed or configured by RRC.

[0200] That is, for each indication field of each block and each TCI state group, the candidate value of the CSI-RS resource ON / OFF indication and / or first power offset selected or indicated by the DCI may be fixed or may be RRC configured.

[0201] The mapping relationship between the TCI state group and each CSI-RS resource may be based on the current RRC configuration. The candidate value may be any of the candidate values ​​described in the first embodiment. That is, a candidate value equal to a first value (e.g., minus infinity or zero) may indicate that the CSI-RS resource is not transmitted by the base station. Still other offset values ​​may indicate respective first and / or second power offsets. The power offsets may be determined in an open-loop or closed-loop manner, and in a relative or absolute manner.

[0202] <First Modification> In a first variant, circuit 120, in operation, determines whether the power offset (first power offset or second power offset) is a first value and / or whether the CSI-RS resource is indicated as not being transmitted by base station 200. In other words, circuit 120 determines whether the power offset indicated by the power level indicator is a first value or whether the CSI-RS resource ON / OFF indication indicates that the CSI-RS resource is not being transmitted by base station 200 (CSI-RS resource OFF). Furthermore, circuit 120 determines whether the CSI-RS is configured with a TCI state setting. The TCI state may correspond to the TCI state indicated by the received TCI state indicator. In other words, circuit 120 may determine that the CSI-RS resource whose power level / CSI-RS resource ON / OFF indication is indicated by the power level indicator is associated with a TCI state group.

[0203] If the first / second power offset is the first value and / or the power level indicator indicates CSI-RS resources OFF, the TCI state associated with the CSI-RS is expected not to be activated, for example, by the MAC CE or indicated in the DCI. If the TCI state is already activated, circuit 120 may deactivate the TCI state.

[0204] The first value may be a value associated with CSI-RS resources OFF, for example, zero W or minus infinity dB, but is not limited to the above values ​​and may be, for example, a predetermined or pre-configured value.

[0205] In other words, if the first / second power offset of a certain CSI-RS resource associated with a TCI state is configured in the RRC configuration to indicate a first value, or the CSI-RS resource is indicated to be OFF and the CSI-RS resource is used for QCL with other channels (PDCCH / PDSCH), the OFF indication / first value does not cause the UE 100 to expect that the TCI state indicated by the TCI state indicator will be activated, for example, by the MAC CE, or indicated, for example, in an L1 TCI indication in the DCI. Furthermore, if the TCI state is already activated by the MAC CE, the first value / OFF indication causes the UE 100 to deactivate the TCI state that references the CSI-RS resource.

[0206] If the TCI state indicated by the TCI state indicator is already indicated by the UE-specific DCI to apply a QCL for other channels (e.g., PDCCH and / or PDSCH) (i.e., the TCI state indicator indicates a TCI state associated with a CSI-RS resource not transmitted by base station 200) (i.e., a CSI-RS resource OFF indication), UE 100 does not apply the indicated TCI state. In this case, UE 100 may switch to a backup or default TCI state, which may be RRC configured or fixed. Furthermore, for this purpose, the mapping between the TCI state and the respective backup or default TCI state may be RRC configured or fixed.

[0207] Therefore, the interaction of the UE 100 with the TCI framework is consistent with the operations performed by the base station 200.

[0208] <Second Modification> In a second variation, after the transceiver 110 receives the power level indicator, the circuit 120 may perform at least one of the following operations:

[0209] If the power offset (first power offset or second power offset) associated with the TCI state indicated by the TCI state indicator is a first value and / or if the TCO state is associated with a CSI-RS resource not being transmitted by base station 200, UE 100 may stop reporting CSI according to the CSI reporting configuration associated with the CSI-RS resource.

[0210] That is, if the first / second power offset associated with the indicated TCI state is a first value, which may be minus infinity, zero, etc., or if a CSI-RS resource OFF indication is associated with the TCI state indicated by the received TCI state indicator (i.e., if the CSI-RS resource is not transmitted by base station 200), UE 100 does not perform CSI reporting for the above CSI-RS. Therefore, the behavior of UE 100 is adapted to take into account the energy saving measures performed by base station 200. Specifically, if the CSI-RS resource is not transmitted by base station 200, UE 100 also does not perform the respective CSI-RS reporting. This may further lead to a reduction in energy consumption on the UE side.

[0211] If the first / second power offset of the CSI-RS associated with the indicated TCI state is a value other than the first value, and / or if the CSI-RS resource transmitted by base station 200 is associated with the TCI state (e.g., the TCI state indicator represents a CSI-RS resource ON indication) and the CSI-RS resource is part of the CSI reporting configuration, UE 100 starts reporting CSI associated with the above CSI reporting configuration when the CSI-RS resource (indicated by the power level indicator representing the CSI-RS resource ON indication) is switched from OFF to ON, or continues reporting CSI. This approach ensures that the behavior of UE 100 is consistent with the power saving procedure performed by base station 200. In particular, it can be ensured that the required CSI reporting is provided to base station 200 by UE 100.

[0212] When UE 100 is configured with multiple sets of CSI reporting configurations, UE 100 may switch between the multiple CSI reporting configuration sets. The switching may be based on a TCI state linked to a CSI-RS indicated as ON (by a power level indicator indicating a TCI state associated with which a CSI-RS resource is transmitted by base station 200, i.e., a CSI-RS resource ON indication) and / or a first / second power offset other than the first value (e.g., other than minus infinity or zero). The multiple CSI configurations may be associated with reported values, i.e., for example, LI, CQI, RI, PMI, L1-RSRP and / or L1-SINR, and optionally a codebook for PMI.

[0213] The number and / or size of CSI reports transmitted by UE 100 may be semi-static or dynamic. In the semi-static case, the UE reports CSI based only on a fixed or configured set of CSI reporting configurations or a fixed or configured number of CSI reporting configurations. That is, the size of the CSI report is kept consistent between base station 200 and UE 100. In the dynamic case, the UE adjusts the size of the CSI report based on the CSI-RS indicated to be ON (by a power level indicator, which is a CSI-RS resource ON indication) or the number of CSI-RS resource set groups indicated to be ON.

[0214] <Further variations> Further variations of the third embodiment are provided according to the third and fourth variations of the first embodiment, in which the indicated power offset is replaced with a power offset associated with the TCI state indicated by the TCI state indicator.

[0215] That is, in a variant of the third embodiment corresponding to the third variant of the first embodiment, the circuit may, in operation, operate depending on the power level and / or whether CSI-RS resources are transmitted by the base station to be associated with the TCI state indicated by the TCI state indicator for a finite period of time after receipt of the power level indicator.

[0216] That is, in the modification of the third embodiment corresponding to the fourth modification of the first embodiment, the transceiver unit 110, during operation, receives CSI-RS resources. The circuitry 120, during operation, calculates a path loss estimate using the first power offset and the received power of the CSI-RS resources. Furthermore, the circuitry 120, during operation, performs uplink power control in response to the calculated path loss estimate.

[0217] In particular, the resulting path loss estimate may be used in uplink power control of one or more of the physical uplink shared channel (PUSCH), the physical uplink control channel (PUCCH), the sounding reference signal (SRS), and / or the physical random access channel (PRACH).

[0218] In this manner, the UE may reduce its energy consumption because it may perform the uplink transmission using reduced transmit power.

[0219] Further embodiments In the first to third embodiments, one of the above-described modifications or a combination of the above-described modifications may be combined.

[0220] In a further embodiment, a UE, a base station, and respective methods similar to those of the first embodiment are provided, where the CSI-RS resources are replaced by SSB / PSS / SSS, and the first offset of the first embodiment may be replaced by a power offset from the SIB configured PSS EPRE or SSS EPRE.

[0221] In further embodiments, the indication described above may be sent in a UE-specific DCI, a cell-common DCI, or a MAC CE.

[0222] In a further embodiment, the circuitry, during operation, determines whether the power level indicator has been successfully received, and if it is determined that the power level indicator has not been successfully received, the transceiver, during operation, transmits an acknowledgement indicator indicating that the power level indicator has not been successfully received, and / or if it is determined that the power level indicator has been successfully received, the transceiver, during operation, transmits an acknowledgement indicator indicating that the power level indicator has been successfully received.

[0223] For example, HARQ-ACK feedback may be provided by the UE. In this regard, if the power level indicator is received via MAC CE, the UE may follow the normal HARQ-ACK procedure. If the power level indicator is received via UE-specific DCI or via group-common DCI, the HARQ-ACK feedback may follow the PUCCH resource indication in the DCI and / or the RRC-configured resources. If the power level indicator is transmitted via group-common DCI, the UE may only provide NACK feedback whose resources follow the PUCCH resource indication in the DCI and / or the RRC-configured resources are used. With this approach, uplink traffic may be reduced because a NACK response is transmitted by the UE only if the power level transmission is not successfully received and a retransmission of the power level indicator can be performed by the base station.

[0224] Furthermore, for example, if there are two potential candidate values ​​of the power level indicator configured by the RRC configuration, only the CSI-RS resource ON / OFF indication may be supported, i.e., the power level indicator may indicate whether the CSI-RS is transmitted by the base station, whereas if more than two values ​​are configured by the RRC, multiple power offset values ​​may be included or defined.

[0225] Hardware and Software Implementations of the Disclosure The present disclosure can be realized by software, hardware, or software in conjunction with hardware. Each functional block described in the above embodiments may be partially or entirely realized as an LSI, which is an integrated circuit. Each process described in the above embodiments may be partially or entirely controlled by a single LSI or a combination of LSIs. The LSI may be composed of individual chips, or may be composed of a single chip that includes some or all of the functional blocks. The LSI may have data inputs and outputs. Depending on the level of integration, the LSI may be referred to as an IC, system LSI, super LSI, or ultra LSI. The integration method is not limited to LSIs; it may also be realized by dedicated circuits, general-purpose processors, or dedicated processors. Furthermore, FPGAs (Field Programmable Gate Arrays), which can be programmed after LSI fabrication, or reconfigurable processors, which allow the connections and settings of circuit cells within the LSI to be reconfigured, may also be used. The present disclosure may be realized as digital or analog processing. Furthermore, if an integrated circuit technology that can replace LSI emerges due to advances in semiconductor technology or other derivative technologies, it is natural that such technology can be used to integrate functional blocks. The application of biotechnology is also a possibility.

[0226] The present disclosure may be implemented in any type of apparatus, device, or system having a communication function (collectively referred to as a communication apparatus).

[0227] A communications device may include a radio transceiver (radio transceiver unit) and processing / control circuitry. The radio transceiver may include a receiver and a transmitter unit, or both. The radio transceiver (transmitter and receiver unit) may include an RF (Radio Frequency) module and one or more antennas. The RF module may include an amplifier, an RF modulator / demodulator, or the like.

[0228] Non-limiting examples of communication devices include telephones (e.g., cell phones, smartphones), tablets, personal computers (PCs) (e.g., laptops, desktops, notebooks), cameras (e.g., digital still / video cameras), digital players (e.g., digital audio / video players), wearable devices (e.g., wearable cameras, smartwatches, tracking devices), game consoles, digital book readers, telehealth / telemedicine devices, communication-enabled vehicles or mobile transportation (e.g., cars, airplanes, ships), and combinations of the above devices.

[0229] Communications equipment is not limited to portable or mobile equipment, but also includes non-portable or fixed equipment, devices, and systems of any kind, such as smart home devices (appliances, lighting equipment, smart meters or metering devices, control panels, etc.), vending machines, and any other "things" that may exist on an Internet of Things (IoT) network.

[0230] Communications include data communications via cellular systems, wireless LAN systems, communications satellite systems, etc., as well as data communications via combinations of these.

[0231] A communications apparatus also includes devices such as controllers and sensors connected or coupled to a communications device that performs the communications functions described in this disclosure, such as controllers and sensors that generate control and data signals used by the communications device to perform the communications functions of the communications apparatus.

[0232] The communication apparatus also includes infrastructure facilities, such as base stations, access points, and any other apparatus, device, or system that communicates with or controls the various apparatuses listed above, but are not limited to these.

[0233] Furthermore, various embodiments may also be implemented by software modules. These software modules are executed by a processor or directly in hardware. A combination of software modules and hardware implementation is also possible. The software modules may be stored on any type of computer-readable storage medium. In particular, according to another implementation, a non-transitory computer-readable storage medium is provided. The storage medium stores a program that, when executed by one or more processors, causes the one or more processors to perform the steps of the method according to the present disclosure.

[0234] By way of non-limiting example, such computer-readable storage media may comprise RAM, ROM, EEPROM, CD-ROM or other optical disk storage, magnetic disk storage or other magnetic storage devices, flash memory, or any other medium that can be used to store desired program code in the form of instructions or data structures and that can be accessed by a computer. Also, any connection is referred to as a computer-readable medium, as appropriate. For example, if instructions are transmitted from a website, server, or other remote source using coaxial cable, fiber optic cable, twisted pair, digital subscriber line (DSL), or wireless technologies such as infrared, radio, and microwave, the coaxial cable, fiber optic cable, twisted pair, DSL, or wireless technologies such as infrared, radio, and microwave are included within the definition of medium. However, it should be understood that computer-readable storage media and data storage media do not include connections, carrier waves, signals, or other transitory media, but instead cover non-transitory tangible storage media. As used herein, disk and disc include compact discs (CDs), laser discs, optical discs, digital versatile discs (DVDs), floppy disks, and Blu-ray discs, where disks typically reproduce data magnetically and discs reproduce data optically with a laser. Combinations of the above should also be included within the scope of computer-readable media.

[0235] Furthermore, it should be noted that individual features of different embodiments may be the subject of other embodiments, individually or in any combination. Those skilled in the art will appreciate that the present disclosure, as set forth in the specific embodiments, may be subject to various changes and / or modifications without departing from the concept or scope of the invention as broadly described. The embodiments described herein are therefore to be considered in all respects as illustrative and not restrictive.

[0236] Further Aspects According to a first aspect, there is provided a User Equipment (UE). The UE, in operation, comprises a transceiver that receives a power level indicator from a base station. The power level indicator indicates a power level of a Channel State Information-Reference Signal (CSI-RS) resource and / or indicates whether the CSI-RS resource is transmitted by the base station. The UE, in operation, further comprises circuitry that operates in response to the power level and / or whether the CSI-RS resource is transmitted by the base station.

[0237] According to a second aspect, there is provided a UE according to the first aspect, wherein the power level represents a power offset between a transmission power of the CSI-RS resource and a transmission power of the synchronization signal.

[0238] According to a third aspect, there is provided a UE according to the second aspect, wherein each of one or more Transmission Configuration Indication (TCI) states is associated with a power level and / or whether a respective CSI-RS resource is transmitted, wherein the transceiver unit, in operation, receives the TCI state indicator as a power level indicator.

[0239] According to a fourth aspect, there is provided a UE according to the second aspect, wherein each of the one or more CSI-RS resource sets is associated with a power level and / or whether the respective CSI-RS resource is transmitted, wherein the transceiver unit operatively receives, as a power level indicator, a CSI-RS resource set indicator indicating the CSI-RS resource set.

[0240] According to a fifth aspect, there is provided a UE as defined in any one of the second to fourth aspects, wherein the transceiver unit, in operation, receives CSI-RS resources. The circuitry, in operation, calculates a path loss estimate using a power offset and a received power of the CSI-RS resources, and performs uplink power control in response to the calculated path loss estimate.

[0241] According to a sixth aspect, there is provided a UE according to the first aspect, wherein the power level represents a power offset between a transmit power of the CSI-RS resource and a transmit power of a physical downlink shared channel (PDSCH).

[0242] According to a seventh aspect, there is provided a UE as defined in any one of the second to sixth aspects, wherein if the circuitry, in operation, determines that (i) the power offset is a first value and / or the CSI-RS resources are indicated as not being transmitted, and (ii) the CSI-RS resources are configured with a Transmission Configuration Indication (TCI) state setting, the circuitry expects the TCI state to be not activated or not indicated in the DCI, or deactivates the TCI state if the TCI state is activated.

[0243] According to an eighth aspect, there is provided a UE as set forth in any one of the second to seventh aspects, wherein after the transceiver unit receives the power level indicator, the circuitry, upon operation, performs at least one of the following operations: (i) stopping CSI reporting in accordance with a CSI reporting configuration associated with the CSI-RS resource if the power offset is a first value and / or the CSI-RS resource is indicated as not being transmitted; (ii) starting or continuing CSI reporting in accordance with the CSI reporting configuration associated with the CSI-RS resource if the power offset is a value different from the first value and / or the CSI-RS resource is indicated as being transmitted; and (iii) switching between a plurality of CSI reporting configuration sets based on the power level indicator.

[0244] According to a ninth aspect, there is provided a UE according to the eighth aspect, wherein the power level represents a power offset between a transmit power of the CSI-RS and a transmit power of the PDSCH, and wherein, when the circuitry starts or continues reporting the CSI after the transceiver receives the power level indicator, the circuitry, in operation, uses the power offset to determine a value to be included in the CSI.

[0245] According to a tenth aspect, there is provided a UE according to any one of the first to ninth aspects, wherein the circuitry operates in operation depending on the power level and / or whether CSI-RS resources are transmitted by the base station in a finite period after receipt of the power level indicator.

[0246] According to an eleventh aspect, there is provided a UE according to any one of the first to tenth aspects, wherein the power level indicator is received via a group common downlink control indicator (DCI), a UE-specific DCI, a cell common DCI, or a Medium Access Control-Control Element (MAC-CE).

[0247] According to a twelfth aspect, there is provided the UE according to any one of the first to tenth aspects, wherein the UE is configured using a starting position of a block in a downlink control indicator (DCI) and / or one or more indices of the block, and the power level indicator is received via the DCI according to the starting position of the block and / or the one or more indices of the block.

[0248] According to a thirteenth aspect, there is provided a UE as set forth in any one of the first to twelfth aspects, wherein the circuitry, upon operation, determines whether the power level indicator has been successfully received. If it is determined that the power level indicator has not been successfully received, the transceiver unit, upon operation, transmits an acknowledgement indicator indicating that the power level indicator has not been successfully received, and / or, if it is determined that the power level indicator has been successfully received, the transceiver unit, upon operation, transmits an acknowledgement indicator indicating that the power level indicator has been successfully received.

[0249] According to a fourteenth aspect, there is provided a method for a user equipment (UE), comprising: (i) receiving a power level indicator from a base station, the power level indicator indicating a power level of a Channel State Information-Reference Signal (CSI-RS) resource and / or indicating whether the CSI-RS resource is transmitted by the base station; and (ii) operating depending on the power level and / or depending on whether the CSI-RS resource is transmitted by the base station.

[0250] According to a fifteenth aspect, there is provided a method as in the fourteenth aspect, wherein the power level represents a power offset between a transmission power of the CSI-RS resource and a transmission power of the synchronization signal.

[0251] According to a sixteenth aspect, there is provided a method as in the fifteenth aspect, wherein each of one or more Transmission Configuration Indication (TCI) states is associated with a power level and / or with whether a respective CSI-RS resource is transmitted, wherein the TCI state indicator is received as a power level indicator.

[0252] According to a seventeenth aspect, there is provided a method as in the fifteenth aspect, wherein each of the one or more CSI-RS resource sets is associated with a power level and / or with whether the respective CSI-RS resource is transmitted, and a CSI-RS resource set indicator indicating the CSI-RS resource set is received as a power level indicator.

[0253] According to an 18th aspect, there is provided a method according to any one of the 15th to 17th aspects, further comprising the steps of receiving CSI-RS resources, calculating a path loss estimate using a power offset and the received power of the CSI-RS resources, and performing uplink power control in response to the calculated path loss estimate.

[0254] According to a 19th aspect, there is provided a method as in the 14th aspect, wherein the power level represents a power offset between a transmission power of the CSI-RS resource and a transmission power of a physical downlink shared channel (PDSCH).

[0255] According to a twentieth aspect, there is provided a method according to any one of the fifteenth to nineteenth aspects, wherein if it is determined that (i) the power offset is a first value and / or the CSI-RS resource is indicated as not being transmitted, and (ii) the CSI-RS resource is configured with a Transmission Configuration Indication (TCI) state setting, then it is expected that the TCI state is not activated or not indicated in the DCI, or if the TCI state is activated, the TCI state is deactivated.

[0256] According to a 21st aspect, there is provided a method according to any one of the 15th to 20th aspects, wherein after the power level indicator is received, at least one of the following operations is performed: (i) stopping CSI reporting according to a CSI reporting configuration associated with the CSI-RS resource if the power offset is a first value and / or the CSI-RS resource is indicated as not being transmitted; (ii) starting or continuing CSI reporting according to a CSI reporting configuration associated with the CSI-RS resource if the power offset is a value different from the first value and / or the CSI-RS resource is indicated as being transmitted; and (iii) switching between a plurality of CSI reporting configuration sets based on the power level indicator.

[0257] According to a 22nd aspect, there is provided a method as in the 21st aspect, wherein the power level represents a power offset between the transmission power of the CSI-RS and the transmission power of the PDSCH, and when reporting of the CSI starts or continues after the power level indicator is received, the power offset is used to determine the value to be included in the CSI.

[0258] According to a 23rd aspect, there is provided a method according to any one of the 14th to 22nd aspects, wherein the method is operated depending on the power level and / or depending on whether CSI-RS resources are transmitted by the base station in a finite period of time after reception of a power level indicator.

[0259] According to a 24th aspect, there is provided a method according to any one of the 14th to 23rd aspects, wherein the power level indicator is received via a group common downlink control indicator (DCI), a UE-specific DCI, a cell common DCI, or a Medium Access Control-Control Element (MAC-CE).

[0260] According to a 25th aspect, there is provided the method of any one of the 14th to 23rd aspects, wherein the UE is configured with a starting position of the block and / or one or more indices of the block in a downlink control indicator (DCI), and the power level indicator is received via the DCI depending on the starting position of the block and / or the one or more indices of the block.

[0261] According to a 26th aspect, there is provided a method according to any one of the 14th to 25th aspects, further comprising determining whether the power level indicator has been successfully received. If it is determined that the power level indicator has not been successfully received, an acknowledgement indicator indicating that the power level indicator has not been successfully received is transmitted, and / or if it is determined that the power level indicator has been successfully received, an acknowledgement indicator indicating that the power level indicator has been successfully received is transmitted.

[0262] According to a 27th aspect, there is provided a base station comprising: circuitry that, when operative, determines a power level of a Channel State Information-Reference Signal (CSI-RS) resource and / or whether the CSI-RS resource is transmitted by the base station; and a transceiver unit that, when operative, transmits a power level indicator to a user equipment (UE), the power level indicator indicating the power level of the CSI-RS resource and / or whether the CSI-RS resource is transmitted by the base station.

[0263] According to a 28th aspect, there is provided a base station according to the 27th aspect, wherein the power level represents a power offset between a transmission power of the CSI-RS resource and a transmission power of the synchronization signal.

[0264] According to a 29th aspect, there is provided the base station according to the 28th aspect, wherein each of the one or more Transmission Configuration Indication (TCI) states is associated with a power level and / or whether a respective CSI-RS resource is transmitted, and the transceiver unit, in operation, transmits a TCI state indicator as a power level indicator.

[0265] According to a 30th aspect, there is provided the base station according to the 28th aspect, wherein each of the one or more CSI-RS resource sets is associated with a power level and / or whether the respective CSI-RS resource is transmitted, wherein the transceiver unit operatively transmits a CSI-RS resource set indicator indicative of the CSI-RS resource set as a power level indicator.

[0266] According to a thirty-first aspect, there is provided a base station as set forth in any one of the twenty-eighth to thirtieth aspects, wherein the transceiver unit, in operation, transmits CSI-RS resources.

[0267] According to a 32nd aspect, there is provided a base station according to the 27th aspect, wherein the power level represents a power offset between a transmission power of the CSI-RS resource and a transmission power of a physical downlink shared channel (PDSCH).

[0268] According to a 33rd aspect, there is provided a base station as described in any one of the 27th to 32nd aspects, wherein the power level indicator is transmitted via a group common downlink control indicator (DCI), a UE-specific DCI, a cell common DCI, or a Medium Access Control-Control Element (MAC-CE).

[0269] According to a 34th aspect, there is provided the base station according to any one of the 27th to 32nd aspects, wherein the UE is configured using a start position of a block in a downlink control indicator (DCI) and / or one or more indices of the block, and the transceiver unit, in operation, transmits a power level indicator via the DCI in response to the start position of the block and / or the one or more indices of the block.

[0270] According to a 35th aspect, there is provided a base station as described in any one of the 27th to 34th aspects, wherein the transceiver unit, in operation, receives an acknowledgement indicator indicating that the power level indicator has not been successfully received by the UE, and / or receives an acknowledgement indicator indicating that the power level indicator has been successfully received by the UE.

[0271] According to a thirty-sixth aspect, there is provided a method for a base station, the method comprising: (i) determining a power level of a Channel State Information-Reference Signal (CSI-RS) resource and / or whether the CSI-RS resource is transmitted by the base station; and (ii) transmitting a power level indicator to a user equipment (UE), the power level indicator indicating a power level of the CSI-RS resource and / or whether the CSI-RS resource is transmitted by the base station.

[0272] According to a thirty-seventh aspect, there is provided a method as recited in the thirty-sixth aspect, wherein the power level represents a power offset between a transmission power of the CSI-RS resource and a transmission power of the synchronization signal.

[0273] According to a 38th aspect, there is provided a method as in the 37th aspect, wherein each of one or more Transmission Configuration Indication (TCI) states is associated with a power level and / or with whether a respective CSI-RS resource is transmitted, the method further comprising transmitting a TCI state indicator as a power level indicator.

[0274] According to a 39th aspect, there is provided a method as in the 37th aspect, wherein each of the one or more CSI-RS resource sets is associated with a power level and / or whether the respective CSI-RS resource is transmitted, the method further comprising transmitting a CSI-RS resource set indicator as the power level indicator, the CSI-RS resource set indicator indicating the CSI-RS resource set.

[0275] According to a fortieth aspect, there is provided a method according to any one of the thirty-seventh to thirty-ninth aspects, further comprising transmitting a CSI-RS resource.

[0276] According to a 41st aspect, there is provided a method as recited in the 36th aspect, wherein the power level represents a power offset between the transmission power of the CSI-RS resource and the transmission power of a physical downlink shared channel (PDSCH).

[0277] According to a 42nd aspect, there is provided a method according to any one of the 36th to 41st aspects, wherein the power level indicator is transmitted via a group common downlink control indicator (DCI), a UE-specific DCI, a cell common DCI, or a Medium Access Control-Control Element (MAC-CE).

[0278] According to a 43rd aspect, there is provided the method according to any one of the 36th to 41st aspects, wherein the UE is configured using a starting position of the block and / or one or more indices of the block in a downlink control indicator (DCI), the method further comprising transmitting a power level indicator via the DCI according to the starting position of the block and / or the one or more indices of the block.

[0279] According to a 44th aspect, there is provided a method according to any one of the 36th to 43rd aspects, further comprising the step of receiving an acknowledgement indicator indicating that the power level indicator has not been successfully received by the UE and / or receiving an acknowledgement indicator indicating that the power level indicator has been successfully received by the UE.

[0280] In summary, there are provided a user equipment (UE), a base station, and corresponding methods for the user equipment and the base station. The UE comprises a transceiver that, in operation, receives a power level indicator from the base station, the power level indicator indicating a power level of a Channel State Information-Reference Signal (CSI-RS) resource and / or indicating whether the CSI-RS resource is transmitted by the base station. The UE further comprises, in operation, circuitry that operates in response to the power level and / or whether the CSI-RS resource is transmitted by the base station.

Claims

1. a transceiver configured, in operation, to receive a power level indicator from a base station, the power level indicator indicating a power level of a Channel State Information-Reference Signal (CSI-RS) resource and / or whether the CSI-RS resource is transmitted by the base station; a circuit that, in operation, operates in response to the power level and / or whether the CSI-RS resource is transmitted by the base station; A user equipment (UE) comprising:

2. the power level represents a power offset between the transmission power of the CSI-RS resource and the transmission power of a synchronization signal. The UE of claim 1.

3. each of the one or more Transmission Configuration Indication (TCI) states is associated with a power level and / or with whether a respective CSI-RS resource is transmitted; the transceiver unit, in operation, receives a TCI status indicator as the power level indicator. The UE of claim 2.

4. each of the one or more CSI-RS resource sets is associated with a power level and / or whether the respective CSI-RS resource is transmitted; In operation, the transceiver receives, as the power level indicator, a CSI-RS resource set indicator indicating a CSI-RS resource set. The UE of claim 2.

5. The transceiver unit, in operation, receives the CSI-RS resource; The circuit, in operation, calculating a path loss estimate using the power offset and the received power of the CSI-RS resource; performing uplink power control in response to the calculated path loss estimate; 5. The UE according to any one of claims 2 to 4.

6. The power level represents a power offset between the transmit power of the CSI-RS resource and the transmit power of a physical downlink shared channel (PDSCH). The UE of claim 1.

7. The circuit, in operation, the power offset is a first value and / or the CSI-RS resource is indicated as not being transmitted; and The CSI-RS resource is configured in a Transmission Configuration Indication (TCI) state setting; When determining The circuitry expects the TCI state to be not activated or indicated in a downlink control indicator (DCI), or deactivates the TCI state if the TCI state is activated. The UE of claim 2.

8. After the transceiver receives the power level indicator, the circuitry, in operation, if the power offset is a first value and / or the CSI-RS resource is indicated as not being transmitted, stopping reporting of CSI according to a CSI reporting configuration associated with the CSI-RS resource; if the power offset is different from the first value and / or the CSI-RS resource is indicated as being transmitted, starting or continuing reporting CSI according to a CSI reporting configuration associated with the CSI-RS resource; switching between a plurality of CSI reporting configuration sets based on the power level indicator; Execute at least one of: The UE of claim 2.

9. the power level represents the power offset between the transmit power of the CSI-RS and the transmit power of the PDSCH, and when the circuitry starts or continues the reporting of the CSI after the transceiver unit receives the power level indicator, the circuitry, in operation, uses the power offset to determine a value to be included in the CSI. The UE of claim 8.

10. and wherein, in operation, the circuitry operates in response to the power level and / or in response to whether the CSI-RS resource is transmitted by the base station within a finite period of time after receipt of the power level indicator. The UE of claim 1.

11. the power level indicator is received via a group-common downlink control indicator (DCI), a UE-specific DCI, a cell-common DCI, or a Medium Access Control-Control Element (MAC-CE); The UE of claim 1.

12. the UE is configured with a starting position of a block in a downlink control indicator (DCI) and / or one or more indices of the block; the power level indicator is received via the DCI according to the starting position of the block and / or the one or more indices of the block. The UE of claim 1.

13. In operation, the circuit determines whether the power level indicator is successfully received; and / or if it is determined that the power level indicator has not been successfully received, the transceiver unit, in operation, transmits an acknowledgement indicator indicating that the power level indicator has not been successfully received. and if it is determined that the power level indicator has been successfully received, the transceiver unit, in operation, transmits an acknowledgement indicator indicating that the power level indicator has been successfully received. The UE of claim 1.

14. 1. A method for user equipment (UE), comprising: receiving a power level indicator from a base station, the power level indicator indicating a power level of a Channel State Information-Reference Signal (CSI-RS) resource and / or indicating whether the CSI-RS resource is transmitted by the base station; operating depending on the power level and / or depending on whether the CSI-RS resource is transmitted by the base station; A method comprising:

15. a circuit that, during operation, determines a power level of a Channel State Information-Reference Signal (CSI-RS) resource and / or whether the CSI-RS resource is transmitted by a base station; a transceiver configured to, in operation, transmit a power level indicator to a user equipment (UE), the power level indicator indicating the power level of the CSI-RS resource and / or whether the CSI-RS resource is transmitted by the base station; A base station comprising:

16. 1. An integrated circuit configured to control user equipment (UE), comprising: a transceiver circuit configured, in operation, to receive a power level indicator from a base station, the power level indicator indicating a power level of a Channel State Information-Reference Signal (CSI-RS) resource and / or whether the CSI-RS resource is transmitted by the base station; a control circuit that, in operation, operates in response to the power level and / or whether the CSI-RS resource is transmitted by the base station; A control circuit comprising:

17. 1. An integrated circuit configured to control a base station, comprising: a control circuit that, during operation, determines a power level of a Channel State Information-Reference Signal (CSI-RS) resource and / or whether the CSI-RS resource is transmitted by the base station; a transceiver circuit configured to, during operation, transmit a power level indicator to a user equipment (UE), the power level indicator indicating the power level of the CSI-RS resource and / or whether the CSI-RS resource is transmitted by the base station; 1. An integrated circuit comprising:

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