User equipment involved in neighboring cell measurement procedure

Abstract

To provide communications devices with a procedure that facilitates improvement of measurement procedures.SOLUTION: A communication device UE has a processor for determining, during operation, at least one radio measurement quantity for at least one radio cell for each measurement period, and determines one from among a plurality of mobility states for the UE, the plurality of mobility states including at least three different mobility states. The processor further determines one or more radio measurement quantities for a serving radio cell in which the UE is located. The processor further determines whether or not to relax radio measurements on one or more neighboring radio cells based on the determined mobility state of the UE and the determined one or more radio measurement quantities for the serving radio cell. A receiver and the processor of the UE perform radio measurements on the one or more neighboring radio cells according to radio measurement requirements if the processor determines not to relax radio measurements on the one or more neighboring radio cells.SELECTED DRAWING: Figure 9

Description

[Technical field]

[0001] The present disclosure is directed to methods, apparatus, and articles in communication systems, such as 3GPP communication systems. [Background technology]

[0002] Currently, the 3rd Generation Partnership Project (3GPP®) is working on technical specifications for the next generation of cellular technology, also known as the fifth generation (5G).

[0003] One objective is to provide a single technical framework that addresses all usage scenarios, requirements, and deployment scenarios (see, for example, Section 6 of Non-Patent Document 1), including at least enhanced mobile broadband (eMBB), ultra-reliable low-latency communications (URLLC), and massive machine type communication (mMTC). For example, deployment scenarios for eMBB may include indoor hotspots, dense urban areas, suburban areas, wide urban areas, and high-speed. Deployment scenarios for URLLC may include industrial control systems, mobile health management (remote monitoring, remote diagnosis, and remote treatment), real-time control of vehicles, and wide-area monitoring and control systems for smart grids. Deployment scenarios for mMTC may include scenarios using a large number of devices with low latency data transmission, such as smart wearables and sensor networks. eMBB and URLLC services are similar in that both require extremely high bandwidth, but differ in that URLLC services preferably require extremely low latency.

[0004] A second objective is to achieve forward compatibility: backward compatibility to Long Term Evolution (LTE, LTE-A) cellular systems is not required, which will facilitate the design of entirely new systems and / or the introduction of new features. [Prior art documents] [Non-patent literature]

[0005] [Non-Patent Document 1] TR 38.913 version 15.0.0 [Non-Patent Document 2] 3GPP TS 38.300 v15.6.0 [Non-Patent Document 3] 3GPP TS 38.211 v15.6.0 [Non-Patent Document 4] ITU-R M.20183 [Non-Patent Document 5] TS 23.501 v16.1.0 [Non-Patent Document 6] 3GPP TS 38.133 v16.0.0 [Non-Patent Document 7] TS 38.331 v15.6.0 [Non-Patent Document 8] 3GPP TS 36.304 v15.4.0 [Non-Patent Document 9] TS 36.133 [Non-Patent Document 10] 3GPP TS 38.304 Summary of the Invention

[0006] One non-limiting exemplary embodiment facilitates providing a procedure that facilitates improved measurement procedures.

[0007] A main aspect of the present disclosure is a communications device having a processor that, during operation, determines at least one radio measurement quantity for at least one radio cell for each measurement period, and a first scaling factor related to a frequency range and a DRX period and a second scaling factor, which is a mitigation scaling factor, are adapted for the measurement period when at least one mitigation criterion is satisfied.

[0008] In one embodiment, the technology disclosed herein features a user equipment (UE) having a processor for determining one of a plurality of mobility states for the UE, the plurality of mobility states including at least three different mobility states. The processor determines one or more radio measurement quantities for a serving radio cell in which the UE is located. The processor determines whether to relax radio measurements on one or more neighboring radio cells based on the determined mobility state of the UE and the determined one or more radio measurement quantities for the serving radio cell. A receiver and the processor of the UE perform the radio measurements on the one or more neighboring radio cells according to radio measurement requirements if the processor determines not to relax radio measurements on the one or more neighboring radio cells.

[0009] It should be noted that the general or specific embodiments may be implemented as a system, a method, an integrated circuit, a computer program, a storage medium, or any selective combination thereof.

[0010] Further benefits and advantages of the disclosed embodiments and various implementations will become apparent from the specification and drawings. These benefits and / or advantages may be obtained individually by the various embodiments and features of the specification and drawings, however, they need not all be present in order to obtain one or more of such benefits and / or advantages. [Brief description of the drawings]

[0011] Exemplary embodiments will now be described in more detail with reference to the accompanying drawings.

[0012] [Figure 1] FIG. 1 illustrates an example architecture of a 3GPP NR system. [Diagram 2] Schematic diagram showing the division of functions between NG-RAN and 5GC [Diagram 3] Sequence diagram of RRC connection setup / reconfiguration procedure [Figure 4] Schematic showing the usage scenarios for Enhanced Mobile Broadband (eMBB), Massive Machine Type Communications (mMTC), and Ultra-Reliable Low Latency Communications (URLLC) [Diagram 5] Block diagram illustrating an exemplary 5G system architecture for a non-roaming scenario [Figure 6] FIG. 1 illustrates when a UE is allowed to relax neighbor cell measurements depending on the serving cell quality and the distinction between stationary and non-stationary UEs according to prior art solutions. [Figure 7] FIG. 1 shows an exemplary simplified structure of a UE and a gNB. [Figure 8] FIG. 1 illustrates a structure of a UE according to an exemplary implementation of an improved measurement procedure. [Figure 9] 1 is a flow diagram of a UE operation according to an exemplary implementation of an improved measurement procedure; [Figure 10] FIG. 2 illustrates whether and how a UE is allowed to relax neighbor cell measurements depending on the UE's mobility state and the serving cell quality according to a first variant of the improved measurement procedure; [Figure 11] FIG. 2 illustrates whether and how a UE is allowed to relax neighbor cell measurements depending on the UE's mobility state and the serving cell quality according to a second variant of the improved measurement procedure; [Figure 12]FIG. 10 illustrates whether and how a UE is allowed to relax neighbor cell measurements depending on the UE's mobility state and serving cell quality according to another variant of the improved measurement procedure; [Figure 13] FIG. 10 illustrates whether and how a UE is allowed to relax neighbor cell measurements depending on the UE's mobility state and serving cell quality according to a further variant of the improved measurement procedure; [Figure 14] FIG. 14 illustrates whether and how a UE is allowed to relax neighbor cell measurements depending on the UE's mobility state and serving cell quality, according to an exemplary implementation of an improved measurement procedure, according to a combination of the solutions of FIG. 10 and FIG. 13. [Figure 15] FIG. 14 is a flow diagram of a UE operation according to an exemplary implementation of an improved measurement procedure, combining the solutions of FIG. 10 and FIG. 13. [Figure 16] FIG. 14 illustrates whether and how a UE is allowed to relax neighbor cell measurements depending on the UE's mobility state and serving cell quality, according to an exemplary implementation of an improved measurement procedure, according to a combination of the solutions of FIG. 11 and FIG. 13. [Figure 17] FIG. 14 is a flow diagram of UE operation according to an exemplary implementation of an improved measurement procedure, combining the solutions of FIG. 11 and FIG. 13. [Figure 18] FIG. 14 illustrates whether and how a UE is allowed to relax neighbor cell measurements depending on the UE's mobility state and serving cell quality, according to an exemplary implementation of an improved measurement procedure, according to a combination of the solutions of FIG. 12 and FIG. 13. [Figure 19] FIG. 14 is a flow diagram of a UE operation according to an exemplary implementation of an improved measurement procedure, combining the solutions of FIG. 12 and FIG. 13. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0013] 5G NR System Architecture and Protocol Stack

[0014] 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 will be completed at the end of 2017, which will allow smartphones compliant with the 5G NR standard to proceed to testing and commercial deployment.

[0015] In particular, the overall system architecture assumes an NG-RAN (Next Generation - Radio Access Network) with gNBs terminating NG radio access user plane (SDAP / PDCP / RLC / MAC / PHY) and control plane (RRC) protocols. 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 that runs the AMF) by an NG-C interface, and to a UPF (User Plane Function) (e.g., a specific core entity that runs 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 2).

[0016] The user plane protocol stack in NR (see, for example, Section 4.4.1 of Non-Patent Document 2) includes a PDCP (Packet Data Convergence Protocol, see Section 6.4 of Non-Patent Document 2), a RLC (Radio Link Control, see Section 6.3 of Non-Patent Document 2), and a MAC (Medium Access Control, see Section 6.2 of Non-Patent Document 2) sublayer, which terminate at the gNB on the network side. In addition, a new sublayer (SDAP, Service Data Adaptation Protocol) of the access stratum (AS) is introduced on top of the PDCP (see, for example, Section 6.5 of Non-Patent Document 2). A control plane protocol stack is also defined in NR (see, for example, Section 4.4.2 of Non-Patent Document 2). An overview of the functions of Layer 2 is described in Section 6 of Non-Patent Document 2. The functions of the PDCP sublayer, the RLC sublayer, and the MAC sublayer are described in clauses 6.4, 6.3, and 6.2, respectively, of 3GPP TS 2011-010111. The functions of the RRC layer are described in clause 7 of 3GPP TS 2011-010111.

[0017] For example, the medium access control layer handles scheduling and scheduling-related functions, including multiplexing of logical channels, as well as handling of various numerologies.

[0018] 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 the transmission of a particular transport channel, and each transport channel is mapped to a corresponding physical channel. For example, the physical channels are PRACH (Physical Random Access Channel), PUSCH (Physical Uplink Shared Channel), and PUCCH (Physical Uplink Control Channel) for the uplink, and PDSCH (Physical Downlink Shared Channel), PDCCH (Physical Downlink Control Channel), and PBCH (Physical Broadcast Channel) for the downlink.

[0019] NR use cases / deployment scenarios include enhanced Mobile Broadband (eMBB), ultra-reliable and low latency communications (URLLC), and massive machine type communications (mMTC), which have diverse requirements in terms of 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 km2 1,000,000 devices per second), wide coverage in harsh environments, and extremely long battery life (15 years) to lower device costs may be preferably required.

[0020] Thus, an OFDM numerology (e.g., subcarrier spacing, OFDM symbol duration, cyclic prefix (CP) duration, 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 duration (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 duration than scenarios with small delay spreads. To maintain a comparable 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. Thus, currently, subcarrier spacings of 15 kHz, 30 kHz, 60 kHz, ... are considered. Symbol duration T u and the subcarrier spacing Δf is expressed 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.

[0021] In the new radio system 5G-NR, for each numerology and carrier, a resource grid of subcarriers and OFDM symbols is defined in the uplink and downlink, respectively. Each element in the resource grid is called a resource element and is identified based on a frequency index in the frequency domain and a symbol position in the time domain (see Non-Patent Document 3).

[0022] Split of 5G NR functions between NG-RAN and 5GC

[0023] Figure 2 shows the functional division 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.

[0024] In particular, the gNB and ng-eNB handle the following key functions: - Radio Resource Management functions, such as Radio Bearer Control, Radio Admission Control, Connection Mobility Control, dynamic resource allocation (scheduling) to UEs in both uplink and downlink directions - IP header compression, encryption, and data integrity protection - Selection of AMF at UE attach time when routing to AMF cannot be determined from information provided by the UE - Routing user plane data to the UPF - Routing control plane information to AMF - Establishing and releasing connections - Scheduling and sending paging messages - Scheduling and transmission of system broadcast information (sent from AMF or OAM) - 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 - NAS message delivery function - Wireless Access Network Sharing - Dual Connectivity - Tight interworking between NR and E-UTRA

[0025] The Access and Mobility Management Function (AMF) handles the following main functions: - Termination of Non-Access Stratum (NAS) signalling - 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)

[0026] In addition, 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 part of packet inspection and policy rule enforcement - Traffic usage reports - An 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) - Validation of uplink traffic (mapping of SDF to QoS flows) - Downlink packet buffering and downlink data notification triggering

[0027] Finally, the Session Management Function (SMF) handles the following major functions: - Session Management - UE IP address allocation and management - UP function selection and control - Configuring traffic steering in the User Plane Function (UPF) to route traffic to the correct destination - Policy enforcement and QoS control - Downlink data notification

[0028] RRC connection setup and reconfiguration procedures

[0029] Figure 3 shows the interactions between the UE, gNB, and AMF (5GC entities) in the NAS part when the UE transitions from RRC_IDLE to RRC_CONNECTED (see Non-Patent Document 2)

[0030] RRC is a higher layer signaling (protocol) used for the configuration of the UE and the gNB. In particular, in this transition, the AMF prepares UE context data (including, for example, PDU session context, security keys, UE radio capabilities, and UE security capabilities, etc.) and sends it to the gNB by an INITIAL CONTEXT SETUP REQUEST. The gNB then activates AS security with the UE, which is performed by the gNB sending a SecurityModeCommand message to the UE and the UE responding with a SecurityModeComplete message to the gNB. The gNB then performs a reconfiguration to establish a signaling radio bearer 2 (SRB2) and a data radio bearer (DRB), which is performed by the gNB sending an RRCReconfiguration message to the UE and the gNB receiving an RRCReconfigurationComplete from the UE in response. In the case of a signaling-only connection, these steps related to RRCReconfiguration are skipped since SRB2 and DRB are not established. Finally, the gNB informs the AMF that the establishment procedure is complete via an INITIAL CONTEXT SETUP RESPONSE.

[0031] Therefore, in the present disclosure, a fifth generation core (5GC) entity (e.g., AMF, SMF, etc.) is provided that has a control circuit that, in operation, 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 via the NG connection. In particular, the gNodeB transmits radio resource control (RRC) signaling including a resource allocation setting information element to the UE via the signaling radio bearer. The UE then performs uplink transmission or downlink reception based on the resource allocation setting.

[0032] Usage scenarios for IMT-2020 and beyond

[0033] Figure 4 shows some of the use cases for 5G NR. The 3rd generation partnership project new radio (3GPP NR) considers three use cases that are envisaged to support a wide variety of services and applications by IMT-2020. The specifications for phase 1 of enhanced mobile broadband (eMBB) have been finalized. Current and upcoming work will include standardization for ultra-reliable and low-latency communications (URLLC) and large-scale machine-type communications, in addition to further extending eMBB support. Figure 4 shows some examples of usage scenarios envisaged for IMT beyond 2020 (see, for example, Figure 2 in Non-Patent Document 4).

[0034] URLLC use cases have stringent requirements on capabilities such as throughput, latency and availability, and are envisioned as one of the enablers of 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. The ultra-high reliability of URLLC is supported by identifying technologies to meet the requirements set by NR URLLC in Release 15. For NR URLLC in Release 15, key requirements include a user plane target latency of 0.5 ms for UL (uplink) and 0.5 ms for DL ​​(downlink). A typical URLLC requirement for a single transmission of a packet is a BLER (block error rate) of 1E-5 for a packet size of 32 bytes with a user plane latency of 1 ms.

[0035] From a physical layer perspective, reliability can be improved in many possible ways. Current scope for improving reliability includes defining separate CQI tables for URLLC, more compact DCI formats, PDCCH repetition, etc. However, as NR becomes more stable and developed (for a key requirement of NR URLLC), the scope for achieving ultra-high reliability can be expanded. Specific use cases for NR URLLC in Release 15 include augmented reality / virtual reality (AR / VR), e-health, e-safety, and mission-critical applications.

[0036] Furthermore, technology enhancements targeted by NR URLLC target latency improvement and reliability improvement. 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 channel, and preemption for downlink. Preemption means that a transmission for which resources are already allocated is aborted and the already allocated resources are used for another transmission with smaller latency / higher priority requirement requested later. 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 (eMBB, etc.). Technology enhancements for reliability improvement include dedicated CQI / MCS tables for a target BLER of 1E-5.

[0037] 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 not sensitive to latency. 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 to enable long battery life.

[0038] As mentioned above, it is expected that the scope of reliability in NR will be broadened. One key requirement necessary in 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 from 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 frequency, time, and / or spatial domains. These areas are generally applicable to reliability, regardless of the specific communication scenario.

[0039] For NR URLC, further use cases with more stringent requirements have been identified, e.g. in factory automation, the transport industry and power supply. The more stringent requirements include higher reliability (up to 10 times faster) depending on the use case. 6 These include: higher availability, packet sizes up to 256 bytes, time synchronization on the order of a few μs (values ​​range from 1 to a few μs depending on the frequency range), and low latency on the order of 0.5-1 ms (with a target latency of 0.5 ms in particular for the user plane).

[0040] Furthermore, for NR URLLC, several technology enhancements are recognized from the physical layer perspective. In particular, PDCCH (Physical Downlink Control Channel) enhancements related to compact DCI, PDCCH repetition, and increased PDCCH monitoring. Furthermore, UCI (Uplink Control Information) enhancements related to HARQ (Hybrid Automatic Repeat Request) enhancements and CSI feedback enhancements. Also, PUSCH enhancements related to minislot level hopping and retransmission / repetition are recognized. The term "minislot" refers to a Transmission Time Interval (TTI) that contains fewer symbols than a slot (a slot containing 14 symbols).

[0041] QoS Control

[0042] The 5G Quality of Service (QoS) model is based on QoS flows and supports both QoS flows that require guaranteed flow bitrates (GBR QoS flows) and QoS flows that do not require guaranteed flow bitrates (non-GBR QoS flows). Thus, at the NAS level, QoS flows are the finest granularity of QoS differentiation in a PDU session. Within a PDU session, QoS flows are identified by a QoS Flow Identifier (QFI) that is conveyed in the encapsulation header over the NG-U interface.

[0043] 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 together with the PDU sessions, and can then configure additional DRBs for the QoS flows of that PDU session (NG-RAN decides when to do so), e.g. as described above with reference to Fig. 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.

[0044] FIG. 5 shows the 5G NR non-roaming reference architecture (see section 4.23 of 3GPP 5). Application Functions (AFs) (e.g., external application servers handling 5G services exemplarily described in FIG. 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 (AFs) that are considered trusted by the operator can be allowed to interact directly with the relevant network functions. Application functions (AFs) that are not allowed by the operator to directly access network functions interact with the relevant network functions using an external exposure framework via the NEF.

[0045] 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 deployed in and run on a cloud computing environment.

[0046] Thus, the present disclosure provides an application server (e.g., an AF in a 5G architecture) having a transmitter that, during operation, sends a request including QoS requirements for at least one of a URLLC service, an eMBB service, and an mMTC service to at least one of the 5GC functions (e.g., a 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, during operation, performs a service using the established PDU session.

[0047] RRM (Radio Resource Management) Measurement

[0048] Radio Resource Measurement (RRM) includes a wide range of techniques and procedures including power control, scheduling, cell search, cell reselection, and radio link or connection monitoring / measurement (see "Requirements for support of radio resource management" in Non-Patent Document 6). RRC in NR 5G supports three states: RRC Idle, RRC Inactive, and RRC Connected (see Section 4.2.1 in Non-Patent Document 7). RRM techniques and reporting mechanisms support UE mobility. RRM-related operations performed by a UE can be broadly categorized based on the UE's RRC state (e.g., the UE is in RRC_Idle, RRC_Inactive, or RRC_Connected state).

[0049] For example, for a UE in IDLE state, RRM includes cell selection and cell reselection, while for a UE in INACTIVE state, RRM includes cell reselection. Cell selection allows the UE to select a suitable cell to camp on to access available services. Cell reselection allows the UE to select a more suitable cell to camp on.

[0050] One important aspect of cell selection and cell reselection is the radio measurements that the UE needs to perform on the serving cell and neighboring cells. When camped on a cell, the UE has to periodically search for a better cell according to cell reselection criteria.

[0051] Briefly, to provide a basic overview of measurements, a UE (NR device) can perform measurements based on reference signals (e.g., CSI-RS, SS blocks, etc.) and derive measurement results from them, which can be used internally by the UE (e.g., cell (re)selection in Idle or Inactive) or by other entities, e.g., the base station for mobility control (e.g., handover in CONNECTED) after receiving some or all measurement results in a corresponding measurement report.

[0052] The measurements can be divided into at least three measurement types. -Intra-frequency NR measurement, Inter-frequency NR measurement ·Rat-to-RAT measurement

[0053] For example, measurements can be configured, for example, by defining one or more measurement objects, where the measurement object defines, for example, the carrier frequencies to monitor. Thus, for each measurement object, one or several reporting configurations can be defined, including reporting criteria (e.g., event-triggered reporting, periodic reporting, and event-triggered periodic reporting, etc.) (see section 9.1 of 3GPP TS 2013-010112). The reporting configurations indicate various combinations of quantities or sets of quantities, for example, channel quality indicator (CQI), rank indication (RI), precoder-matrix indicator (PMI), which are jointly referred to as channel state information (CSI).

[0054] Furthermore, different radio measurement quantities can be configured for the UE, e.g. Reference Signal Received Power (RSRP), Reference Signal Received Quality (RSRQ), etc. A further possible radio measurement quantity can be the Signal-to-Interference plus Noise Ratio (SINR). One or more of these radio measurement quantities can be measured by the UE, e.g. to determine the radio quality of a cell, e.g. the serving radio cell or a neighboring radio cell.

[0055] According to one example implementation in the 5G NR standardization case, measurements are performed by an INACTIVE or IDLE UE for intra-frequency NR neighbor cells, inter-frequency NR neighbor cells, and inter-RAT E-UTRAN neighbor cells as follows (see sections 4.2.2.3, 4.2.2.4, and 4.2.2.5 of 3GPP TS 2013-010366):

[0056] The UE shall measure at least T measure,NR_intra (see Table 4.2.2.3-1 below)

[0057] [Table 1]

[0058] The UE shall transmit at least K carrier *T measure,NR_inter (see Table 4.2.2.4-1 below), where the parameter K carrier is the number of NR inter-frequency carriers indicated by the serving cell.

[0059] [Table 2]

[0060] A detected cell (e.g., an inter-RAT neighbor cell) is considered to be at least (N EUTRA_carrier )*T measure,EUTRAN The parameter N must be measured every EUTRA_carrier is the total number of configured E-UTRA carriers in the neighbor frequency list.

[0061] [Table 3]

[0062] Measurement Relaxation in LTE

[0063] The relaxation criteria are provided to allow the UE to skip neighbor cell measurements and thus save the UE's power. Already in LTE systems, the UE was able to relax neighbor cell measurements under certain circumstances. The following exemplary implementation of the measurement relaxation procedure is provided according to the 3GPP LTE standard (see section 5.2.4.2 of 3GPP LTE 8).

[0064] [Table 4]

[0065] Furthermore, NarrowBand Internet of Things (NB-IoT) devices are (mostly) stationary and should be allowed to relax neighbor cell measurements more frequently, although different measurement relaxation rules are provided for cell reselection of such NB-IoT devices (see section 5.2.4.2a of 3GPP TS 2013-010112).

[0066] [Table 5]

[0067] To better understand the above parameters, Non-Patent Document 8 provides the following definitions:

[0068] The parameter "Squal" should be understood, for example, as a cell selection quality value (dB) (e.g., RSRQ). The parameter "Srxlev" should be understood, for example, as a cell selection RX level value (dB) (e.g., RSRP). IntraSearchP ” specifies the Srxlev threshold (in dB) for intra-frequency measurements. The parameter “S IntraSearchQ ” specifies the Squal threshold (in dB) for intra-frequency measurements. The parameter “S nonIntraSearchP Parameter "S" specifies the Srxlev threshold (in dB) for E-UTRAN inter-frequency and inter-RAT measurements. nonIntraSearchQ " specifies the Squal threshold (in dB) for E-UTRAN inter-frequency and inter-RAT measurements.

[0069] In fact, the above relaxation rules for neighbor cell measurements are implemented as a rule to ensure that the corresponding radio quality measurements for the serving cell (here, e.g., “Squal”, “Srxlev”) do not exceed the corresponding thresholds (here, e.g., “S IntraSearchP ", "S IntraSearchQ ", "S nonIntraSearchP ", "S nonIntraSearchQ "). For example, this can be understood in that when the UE is in the cell center (e.g., the serving cell quality experienced by the UE is high enough), the neighbor cell measurements can be relaxed, whereas when the UE is in the cell edge (e.g., the serving cell quality experienced by the UE is not high enough), the neighbor cell measurements should not be relaxed.

[0070] Furthermore, the LTE 3GPP standard provides mitigation monitoring measurement rules that define further mitigations in addition to those mentioned above (see Non-Patent Document 8).

[0071] [Table 6]

[0072] Parameter "S SearchDeltaP " specifies the relaxed monitoring Srxlev delta threshold (in dB). In fact, the above relaxed monitoring criteria is based on the fact that the radio quality (here, Srxlev) has not changed significantly over the past period (here, "T SearchDeltaP ") did not change much during the period (here, below the threshold " SearchDeltaP "). This mitigation solution can be understood as determining the mobility of a UE through an evaluation of serving cell quality changes during a certain period of time. For example, a stationary UE (e.g., serving cell quality does not change or changes only slightly) can significantly relax neighbor cell measurements, while this does not apply to a non-stationary UE (e.g., when the serving quality changes more than a corresponding threshold).

[0073] In short, as described above, neighbor cell measurements are performed when one or more radio measurement quantities for a serving cell meet a certain criteria (here, for example, "Srxlev>S IntraSearchP and Squal>S IntraSearchQ ", "Srxlev>S nonIntraSearchP and Squal>S nonIntraSearchQ ", "(Srxlev Ref -Srxlev) SearchDeltaP " and for NB-IoT devices, "Srxlev>S IntraSearchP " is satisfied, by allowing the UE to choose not to perform measurements (be it intra-frequency measurements on an adjacent radio cell, or inter-frequency measurements on an adjacent radio cell, or inter-RAT measurements on an adjacent radio cell).

[0074] Measurements and Measurement Mitigation in 5G NR

[0075] ​​Correspondingly, according to an exemplary current solution for 5G NR, measurement rules are already defined that allow the UE to not perform neighbor cell measurements in certain situations (see section 5.2.4.2 of 3GPP TS 21.2010).

[0076] [Table 7]

[0077] As is evident from the above, and quite similar to the corresponding LTE solution in TS 36.133, the above relaxation of neighbor cell measurements is based on the assumption that the corresponding radio quality measurements for the serving cell (here, e.g., “Squal”, “Srxlev”) fall below the corresponding thresholds (here, e.g., “S IntraSearchP ", "S IntraSearchQ ", "S nonIntraSearchP ", "S nonIntraSearchQ " is based on certain radio quality related measurement relaxation criteria that are met when the

[0078] Current RRM power saving research addresses ways in which it may be possible to additionally reduce the power consumption of RRM measurements and seeks to define how to implement RRC measurement mitigation. Some mitigation solutions already adopted in 3GPP LTE can be used as a starting point to consider how measurement mitigation can be improved in 5G NR.

[0079] For example, one further relaxation for 5G NR could be based on the amount of serving cell quality change during a certain period of time, as implemented in LTE, thus effectively allowing significant measurement relaxation for stationary UEs.

[0080] However, the inventors have determined that applying the same or similar LTE solutions to 5G NR would have drawbacks and would not be optimal for NR UEs to simultaneously conserve power while enabling UE mobility.

[0081] For example, some measurement relaxation rules used for LTE UE (e.g., for intra-frequency measurements: Srxlev>S IntraSearchP and Squal>S IntraSearchQ , for inter-frequency and inter-RAT measurements: Srxlev>S nonIntraSearchP and Squal>S nonIntraSearchQ ) allows a UE to choose not to perform measurements on neighboring radio cells if the serving cell radio quality is high enough. In other words, a UE is allowed not to perform neighboring radio cell measurements at all if it is not at a cell edge. However, this can be problematic for high mobility UEs that can move to the cell edge in a short time (due to high mobility), because in such cases cell selection / reselection may not be performed in a timely manner due to missing measurements. This has a negative impact on mobility performance. Such problems may occur more frequently in the case of 5G NR FR2 (Frequency Range 2 includes the millimeter frequency band from 24.25 GHz to 52.6 GHz, which offers a shorter range than the band in FR1 but a higher available bandwidth), because the cell size is usually small, so there is a high probability that a high mobility UE will move from the cell center to the cell edge in a very short time.

[0082] On the other hand, UEs at the cell edge (e.g., serving cell radio quality below a threshold) are not allowed to relax the measurement requirements. This is also the case for UEs that are non-stationary but are low mobility UEs and therefore are not allowed to save power at all. However, this is not necessarily optimal when applied to low mobility UEs. This therefore causes low mobility UEs to consume power unnecessarily, even though they would not need measurements for mobility purposes due to their low mobility.

[0083] In summary, current solutions consider the serving cell quality and the stationary / non-stationary attribute of the UE independently of each other, which is one of the reasons that leads to the above mentioned drawbacks. In short, if the serving cell quality is good enough, the UE is allowed not to perform measurements regardless of its level of mobility. On the other hand, if the UE is stationary and not moving enough, the UE is allowed not to perform measurements regardless of its location in the cell.

[0084] Fig. 6 illustrates in a simplified exemplary manner the relationship between UE mobility state and serving cell quality and the resulting measurement requirements for UEs. On the x-axis the mobility state of the UE is shown, distinguishing between stationary and non-stationary UEs. On the y-axis the serving cell quality experienced by the UE is shown, distinguishing between UEs that are at the cell edge (e.g. below a threshold, here called S1) and UEs that are not at the cell edge (e.g. in the cell center, above the threshold S1).

[0085] As shown in FIG. 6, the solution for LTE (and also for 5G NR if fully adopted) provides that stationary UEs are essentially always allowed not to perform neighbor cell measurements. Meanwhile, measurement relaxation based on serving cell radio quality is illustrated in FIG. 6 according to threshold S1. For ease of explanation, only one threshold S1 (which can be Srxlev (RSRP) or Squal (RSRQ) or a virtual combination of Srxlev and Squal) is used to conceptually visualize the measurement relaxation based on serving cell quality. As is clear, UEs whose serving cell quality is above threshold S1 are allowed not to perform neighbor cell measurements.

[0086] The inventors have observed that currently envisioned solutions for 5G NR measurement mitigation only distinguish between two UE behaviors: 1) measure or 2) do not measure. This is quite restrictive and makes optimizing UE power consumption difficult. A more fine-grained control mechanism would be beneficial.

[0087] Furthermore, the inventors have observed that currently envisioned solutions for 5G NR measurement mitigation only distinguish the UE's capability in a binary way: stationary vs. non-stationary, and the UE's location in a binary way: cell edge vs. non-cell edge. Again, this is rather limiting and makes optimizing UE power consumption difficult. A more fine-grained control mechanism would be beneficial.

[0088] Correspondingly, there is a need for improvements to the measurement procedures performed by the UE, in particular how to relax the measurement requirements to provide the UE with power saving opportunities. Improvements to the measurement procedures may facilitate overcoming one or more of the problems identified above.

[0089] In the following, UEs, base stations, and procedures that meet such needs are described for new radio access technologies envisioned for 5G mobile communication systems, but which may also be used in LTE mobile communication systems. Various implementations and variations are also described. The following disclosure has been facilitated by, and may be based, for example, at least in part on, the above discussion and discoveries.

[0090] In general, it should be noted that many assumptions are made herein to allow the principles underlying the present disclosure to be explained in a clear and understandable manner. However, these assumptions should be understood as merely examples made herein for illustrative purposes, without limiting the scope of the present disclosure. Those skilled in the art will recognize that the principles of the following disclosure and claims can be applied to various scenarios and in ways not explicitly described herein.

[0091] Furthermore, some of the terms such as procedures, entities, layers, etc. used below are closely related to the terms used in the LTE / LTE-A system or in the current 3GPP 5G standardization, even though the specific terms used in the context of new radio access technologies for the upcoming 3GPP 5G communication system have not yet been fully determined or may eventually change. Therefore, the terms may be changed 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 should not be limited to the specific terms used illustratively in this specification due to the lack of other more recent or finally agreed upon terms, but should be more broadly understood in terms of the functions and concepts underlying the functions and principles of the present disclosure.

[0092] For example, a mobile station or mobile node or user terminal or user equipment (UE) is a physical entity 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 functions to other functional entities of the same or other nodes or networks. A node may have one or more interfaces that connect the node to communication facilities or media that allow the node to communicate. Similarly, a network entity may have logical interfaces that connect functional entities to communication facilities or media that allow the node to communicate with other functional entities or corresponding nodes.

[0093] The term "base station" or "radio base station" as used herein 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 or other nodes or networks. The physical entity performs several control tasks for the communication devices, including one or more scheduling and configuration. It should also be noted that base station functions and communication device functions may be integrated in a single device. For example, a mobile terminal may also implement the functions of a base station for other terminals. The term used in LTE is eNB (or eNodeB), while the term currently used in 5G NR is gNB.

[0094] 7 shows a general, simplified, exemplary block diagram of a user equipment (also called a communication device) and a scheduling device (here, illustratively assumed to be located in a base station, e.g., an eLTE eNB (alternatively called ng-eNB) or a gNB in ​​5G NR). The UE and the eNB / gNB communicate with each other over (radio) physical channels using their respective transceivers.

[0095] A communication device may have a transceiver and a processing circuit. The transceiver may then have a receiver and a transmitter and / or function as a receiver and a transmitter. The processing circuit may be one or more hardware, such as, for example, one or more processors or any LSI. Between the transceiver and the processing circuit, there are input / output points (or nodes) through which the processing circuit can control the transceiver during operation, i.e., control the receiver and / or the transmitter and exchange receive / transmit data. The transceiver may include, as a transmitter and receiver, an RF (radio frequency) front including one or more antennas, amplifiers, RF modulators / demodulators, etc. The processing circuit may implement control tasks such as controlling the transceiver to transmit user data and control data provided by the processing circuit and / or to receive user data and control data that are further processed by the processing circuit. The processing circuit may also be responsible for performing other processes, such as, for example, judging, deciding, calculating, measuring, etc. The transmitter may be responsible for performing the transmitting process and other processes related thereto. The receiver may be responsible for performing the receiving process and other processes related thereto (eg, monitoring the channel, etc.).

[0096] In the following, improved measurement procedures are described regarding how to and not to perform radio measurements on neighboring cells.

[0097] Figure 8 shows a simplified exemplary UE structure according to one solution of an improved measurement procedure, which can be implemented based on the general UE structure described in relation to Figure 7. The various structural elements of the UE shown in this figure can be interconnected with each other, for example, by means of corresponding input / output nodes (not shown), for example, to exchange control and user data as well as other signals. Although not shown for purposes of illustration, the UE may include further structural elements.

[0098] As can be seen from FIG. 8, the UE may include UE mobility state determining circuitry, serving cell measurement quantity determining circuitry, and measurement mitigation determining circuitry, as well as receiver and processing circuitry for performing radio measurements.

[0099] Thus, as will become apparent from the disclosure below, in this case the processing circuitry may be exemplarily configured to at least partially perform one or more of: determining one of a plurality of mobility states for the UE; determining one or more radio measurement quantities of the serving radio cell; deciding whether to relax radio measurements on one or more neighboring radio cells; and performing radio measurements on one or more neighboring radio cells.

[0100] Thus, the receiver may be exemplarily configured to at least partially perform one or more of: performing radio measurements on one or more neighboring radio cells, etc.

[0101] One solution, which will be further described in more detail below, is implemented by a UE including: a processor of the UE determines one from among a plurality of mobility states for the UE, the plurality of mobility states including at least three different mobility states; the processor further determines one or more radio measurement quantities of a serving radio cell in which the UE is located; the processor further determines whether to relax radio measurements on one or more neighboring radio cells based on the determined mobility state of the UE and the determined one or more radio measurement quantities of the serving radio cell; a receiver and a processor of the UE perform radio measurements on the one or more neighboring radio cells according to radio measurement requirements if the processor determines not to relax radio measurements on the one or more neighboring radio cells.

[0102] A corresponding sequence diagram of exemplary UE operations along the above lines is shown in FIG.

[0103] Correspondingly, a UE is provided that performs an exemplary improved neighbor cell measurement method, which facilitates at least the following advantages: The limitations identified for the prior art solutions are resolved since at least three different mobility states exist for the UE, and since the decision whether to relax neighbor cell measurements depends on the mobility state of the UE and the number of radio measurements. Thus, neighbor cell measurement relaxation can be applied more precisely, which facilitates optimal power saving while at the same time only negatively impacting the supported mobility of the UE.

[0104] In the following, the above solution as well as variations and further improvements of the above solution will be explained in more detail.

[0105] For the following description of the solution for the improved handover procedure, some basic assumptions are exemplarily made herein. For example, it is assumed that the UE is already configured and supports performing radio measurements on one or more neighboring radio cells. Although some of the following description is mainly made with respect to a 5G NR communication system, the improved measurement procedure is also applicable to LTE or LTE-A communication systems. Furthermore, when considering the implementation of the current 3GPP standard for 5G NR (also for LTE), it is assumed that the UE is in RRC_Idle or RRC_Inactive state and performs cell selection or cell reselection with the requirement to perform radio measurements of neighboring radio cells to find a suitable or better cell to camp on. Thus, the UE is not actively communicating with the network, and the UE may not experience a communication interruption due to the relaxed measurement requirements. Conversely, for a UE in the RRC_Connected state, the following improved measurement procedures and relaxations do not need to be applied, and rather, the measurement requirements should not be relaxed at all in order not to incur a connection interruption. However, although this is not assumed in the following, the improved measurement procedure may also be applied to UEs in a connected state.

[0106] Furthermore, radio measurements on neighboring cells and serving cells can be performed to obtain parameters reflecting each radio cell quality, which can be reflected in corresponding radio measurement quantities. The radio measurement quantities can be configured for the UE and can include, for example, Reference Signal Received Power (RSRP), Reference Signal Received Quality (RSRQ), and Signal-to-Interference plus Noise Ratio (SINR).

[0107] According to the above solution, at least three mobility states are distinguished for the UE and are used to decide whether to relax neighbor cell measurements or not. Exemplarily, in the context of the improved measurement procedure, the UE can be in a low mobility state, a medium mobility state or a high mobility state. Furthermore, a stationary mobility state can also be considered, but this is less relevant for the improved measurement method, since a more fine-grained control of neighbor cell measurement relaxation for stationary UEs may not be necessary (e.g., stationary UEs never perform neighbor cell measurements). Nevertheless, the improved neighbor cell measurement method can also be applied when four or more different mobility states of the UE are distinguished. However, in the following, the concept underlying the improved neighbor cell measurement method is explained using the above-mentioned three different mobility states (low, medium, high).

[0108] The mobility state of a UE can be determined by the UE in a variety of different ways. For example, the following information and parameters can be determined and used to determine the mobility state of a UE:

[0109] As a first example, the number of cell reselections in a suitable past period can be analyzed. In this regard, a time amount and one or more thresholds are set for the UE. In general, it is assumed that the higher the number of cell reselections, the higher the mobility level of the UE. According to one exemplary implementation, two thresholds (i.e., a medium threshold and a high threshold) can be defined. In this case, if the number of cell reselections of the UE is below the medium threshold, the UE can be determined to be in a low mobility state (or a normal mobility state as used in Non-Patent Document 10), if the number of cell reselections of the UE is above the medium threshold but below the high threshold, the UE can be determined to be in a medium mobility state, and if the number of cell reselections of the UE is above the high threshold, the UE can be determined to be in a high mobility state. Alternatively or additionally, different periods can be defined to distinguish different mobility states based on the number of cell reselections.

[0110] A similar criterion to the number of cell reselections is the number of beam changes in the past period. Again, it is assumed that the higher the number of beam changes, the higher the mobility of the UE. According to one exemplary implementation, two thresholds (i.e., medium and high thresholds) can be defined. In this case, if the number of beam changes of the UE is less than the medium threshold, the UE can be determined to be in a low mobility state, if the number of beam changes of the UE is greater than the medium threshold but less than the high threshold, the UE can be determined to be in a medium mobility state, and if the number of beam changes of the UE is greater than the high threshold, the UE can be determined to be in a high mobility state. Alternatively or additionally, different periods can be defined to distinguish different mobility states based on the number of beam changes.

[0111] Another criterion for determining the mobility state of a UE is the fading situation on the serving cell radio measurement quantities in the past time period. Here, it is assumed that the received signal strength changes more or less when the UE moves. The amount of change during a certain time period therefore allows to distinguish different mobility states of the UE. For example, if such changes occur in a relatively short time, the UE can be considered to be in a high mobility state, while a UE in a medium mobility state would be defined as experiencing less changes during the same amount of time or similar changes during a longer amount of time. Finally, a low mobility UE will experience only small changes in the relevant radio measurement quantities (reflecting the serving cell signal strength). Therefore, according to a certain exemplary implementation, appropriate thresholds for the amount of change in the serving cell signal strength and / or the time period can be defined and used to distinguish the mobility states of the UE.

[0112] Furthermore, the mobility state can be derived from the location information of the UE during a past period. The location information can be obtained, for example, from a Global Positioning System (GPS) signal that the UE can monitor. For example, based on the location information, the UE can determine its own moving speed and thus derive the mobility state using an appropriate threshold value for the moving speed.

[0113] According to further criteria, a UE is defined to be in a certain mobility state based on the characteristics of the UE. For example, a UE mounted in a vehicle can be considered as a high mobility UE by definition. Correspondingly, such a vehicular UE would be a high mobility UE even if the vehicle and the UE have not been moving for a significant period of time. For example, such a UE can be considered as a high mobility UE if the historical records (e.g., log files) show that the UE always appears in different cells. Such a criterion has the advantage that it does not require the UE to perform measurements repeatedly.

[0114] Other criteria that may be used to determine the mobility state of a UE are based on the type of UE. For example, a UE that supports or actively uses Ultra-Reliable Low-Latency Communication (URLLC) may be defined as a high mobility UE, since relaxation of neighbor cell measurements should be avoided for low latency UEs. For example, a UE configured to perform Mission Critical Services (i.e., the UE's Access Identity is equal to 2) may be defined as a high mobility UE, since power saving is not an important aspect for such UEs (instead, mobility performance is an important aspect). Again, the UE does not need to repeatedly perform any measurements and complex decisions to derive its mobility state.

[0115] The UE may determine its mobility state based on one or a combination of several of the above criteria.

[0116] One of the above steps is for the UE to determine one or more radio measurement quantities of the serving cell in which it is located, where the radio measurement quantities may be, for example, RSRP, RSRQ, or SINR. The radio measurements may be performed, for example, on reference signals transmitted by the serving base station.

[0117] The improved neighbor cell measurement procedure should also give the UE the opportunity to save power by relaxing neighbor cell measurements, if possible. According to an exemplary implementation of the improved neighbor cell measurement procedure, relaxation of neighbor cell measurements can be achieved either by not performing neighbor cell measurements at all or by performing neighbor cell measurements according to the relaxed radio measurement requirements. Not performing neighbor cell measurements maximizes the power saving potential in the UE, but may be harmful to supporting mobility and thus delaying cell reselection. On the other hand, introducing the concept of relaxed radio measurement requirements allows providing a configurable trade-off between the benefits of power saving and the adverse effects of relaxed measurements. For example, normal, unrelaxed radio measurement requirements require the UE to perform neighbor cell measurements at least every certain period (e.g., at least once every second). In such a case, the relaxed radio measurement requirements may allow the UE to relax neighbor cell measurements to be performed less frequently (e.g., at least once every five seconds) compared to the unrelaxed requirements. Thus, in contrast to a binary mitigation choice of performing or not performing neighbor cell measurements, the mitigation of neighbor cell measurements for the UE can be more precisely controlled with due consideration of real-world needs and opportunities to save power.

[0118] According to one example implementation, such a relative relaxation of radio measurement requirements based on the relaxed measurement requirements can be achieved by defining a scaling factor to be used in combination with the non-relaxed normal radio measurement requirements: In the above use case where the relaxed measurements are performed every 5 seconds compared to every 1 second with the non-relaxed measurements, the scaling factor would be 5.

[0119] The relative relaxation can also depend on the mobility state of the UE, such that different scaling factors are used by the UE in different mobility states. For example, for high mobility UEs, the scaling factor should be rather small so that the relaxation of measurements is small and thus the adverse impact on the mobility of the high mobility UE is limited. On the other hand, for low mobility UEs, the scaling factor can be higher in order to achieve higher power savings with a lower risk of increased adverse impact on the mobility of the low mobility UE.

[0120] Additionally, the relative relaxation may also depend on radio measurements of the serving cell (e.g., reflecting the UE's location within the cell). For example, a UE whose serving cell signal strength is determined to be high (e.g., the UE is in the cell center) may use a scaling factor of infinity (∞) (meaning that no neighbor cell measurements need to be performed). A UE whose serving cell signal strength is determined to be medium (e.g., the UE is not in the cell center, although it is a non-cell edge case) may use a scaling factor of greater than one (>1) (meaning that some relaxation of measurements applies). A UE whose serving cell signal strength is determined to be low (e.g., the UE is in the cell edge) may use a scaling factor of equal to one (=1) (meaning that neighbor cell measurement relaxation does not apply).

[0121] According to one possible exemplary implementation in a 5G NR standardized communication system, the corresponding measurement instructions may be adapted to support such a scaling factor for implementing the relaxation of neighbor cell measurements. In particular, 3GPP TS 2013-01-13443 provides measurement rules for intra-frequency cells, inter-frequency cells, and inter-RAT cells (see subsections 4.2.2.3, 4.2.2.4, and 4.2.2.5), each of which has a table indicating parameters for measurement.

[0122] According to this implementation, the measurement rules and tables may be adapted as follows:

[0123] In the intra-frequency cell measurements and inter-frequency cell measurements tables, the parameter T measure,NR_intra and Tmeasure,NR_inter A scaling factor N1 is already used, which affects the length of the DRX period. As currently standardized, the scaling factor depends on the frequency range and the DRX period. Furthermore, the scaling factor N1 can be adapted by another scaling factor k (N1'=N1*k) which implements a relaxation of the neighbor cell measurements depending on the mobility state or cell location as described above, where k can be a positive integer signaled in the system information. In line with the above, if more additional relaxation scaling factors are used, several coefficients k1, k2, k3, ... can be defined.

[0124] For example, the corresponding table is adapted as follows: measure,NR_Intra and T measure,NR_Inter In the column, the N1 parameter has been replaced with N1'.

[0125] [Table 8]

[0126] [Table 9]

[0127] The inter-RAT cell measurements currently defined in 3GPP TS 2013-01-03343 do not use the scaling factor N1. Therefore, an additional scaling factor k can be introduced to implement measurement relaxation according to the improved measurement procedure as described above. As is evident from the compatibility table, T measure,EUTRAN The columns of are expanded by a factor k.

[0128] [Table 10]

[0129] The improved neighbor cell measurement procedure should give the UE the opportunity to save power by relaxing neighbor cell measurements, if possible. Thus, as mentioned above, the improved method includes a step of deciding by the UE whether to relax radio measurements on one or more neighbor radio cells. This decision is based on the current mobility state of the UE and on radio measurements performed by the UE on the serving cell (and therefore is based on both). First, we define different relaxation criteria (related to the measured radio quality and therefore also exemplarily referred to as radio quality related measurement relaxation criteria) and then explain how those radio quality related measurement relaxation criteria additionally depend on the mobility state of the UE in order to implement the steps of the improved method of deciding whether to relax neighbor cell radio measurements based on both the mobility state of the UE and the measured radio measurement quantities.

[0130] According to an example implementation, whether to relax neighbor cell measurements can be determined by determining whether one or more of a plurality of relaxation criteria are met. A first relaxation criterion is met when one or more measured radio measurement quantities for a serving radio cell have changed less than a threshold amount during a past period. In other words, relaxation of neighbor cell measurements can be applied when one or more radio measurement quantities do not change significantly. The radio measurement quantities can be, for example, RSRP, RSRQ, or SINR parameters.

[0131] According to one exemplary implementation, the first relaxation criterion is met when one radio measurement quantity (e.g., RSRP, RSRQ, or SINR) changes below a corresponding threshold (e.g., RSRP-based threshold, RSRQ-based threshold, or SINR-based threshold, respectively), whereas according to a further implementation, the first relaxation criterion is met when two or more radio measurement quantities (e.g., two or more of RSRP, RSRQ, SINR) change below a corresponding threshold (e.g., RSRP-based threshold, RSRQ-based threshold, or SINR-based threshold, respectively).

[0132] According to a specific exemplary implementation in a 5G NR standardized communication system, the first mitigation criterion may be similar to the mitigated monitoring solution of section 5.2.4.12 of the above-mentioned non-patent document 8. Thus, the UE may obtain the following: (SrxlevRef-Srxlev) SearchDeltaP It is determined that the first relaxation criterion is satisfied when: [Table 11]

[0133] The UE may then therefore choose not to perform intra-frequency or inter-frequency measurements on neighboring cells if this first mitigation criterion is met for a certain period of time.

[0134] Instead of or in addition to the above first relaxation criterion, a second relaxation criterion may be used to determine whether to relax the neighbor cell measurements, and this second relaxation criterion is met when one or more of the radio measurement quantities measured for the serving radio cell are greater than a respective quantity threshold. The radio measurement quantities may be, for example, RSRP, RSRQ, or SINR parameters, respectively. For example, assuming that the radio measurement quantity is RSRP, the second relaxation criterion provides a comparison of the measured RSRP value with an appropriate RSRP threshold. According to another example, the second relaxation criterion is based on a comparison of two or more measured quantities with respective thresholds, and the second relaxation criterion is considered to be met only if the two or more measured quantities all exceed their respective thresholds.

[0135] According to a specific exemplary implementation in a 5G NR standardized communication system, the second mitigation criterion may be similar to the mitigation solution in the above-mentioned Non-Patent Document 8. For example, when the serving cell is (Srxlev>S IntraSearchP and Squal>S IntraSearchQ ), the UE may choose not to perform intra-frequency measurements, and the serving cell satisfies Srxlev>S nonIntraSearchP and Squal>S nonIntraSearchQ ​If the UE satisfies Srxlev>S, the UE may choose not to perform measurements on E-UTRAN inter-frequency or inter-RAT frequency cells. Other second mitigation criteria may be applied for certain types of UEs, e.g., NB IoT UEs. Here, for example, if the serving cell satisfies Srxlev>S IntraSearchP If Srxlev>S, the UE may choose not to perform intra-frequency measurements and the serving cell nonIntraSearchP If

[0136] According to one exemplary implementation, each of the two relaxation criteria by itself justifies the neighbor cell measurements being relaxed. The alternative neighbor cell measurements are relaxed only if both the first and second relaxation criteria are met. In the following, it is exemplarily assumed that meeting one of the relaxation criteria is sufficient for the UE to relax the neighbor cell measurements.

[0137] As mentioned above, according to the improved measurement procedure, the UE decides whether to relax neighbor cell measurements based on both the radio measurement quantity and the mobility state of the UE. This can be implemented in several different ways, as described below. For example, making the radio quality related measurement relaxation criteria (see example above) dependent on the mobility state of the UE, in order to take into account not only the radio measurements but also the mobility state when deciding on the relaxation of neighbor cell measurements.

[0138] According to a first variant of the relaxation decision, the second relaxation criterion introduced above (when one or more of the measured radio measurement quantities for the serving radio cell are greater than the respective quantity threshold) is made dependent on the mobility state of the UE as follows: For example, for a high mobility UE, the second relaxation criterion is never met. Thus, for example, even if the UE experiences very good signal strength from its serving cell and exceeds the corresponding threshold (e.g., the UE is in the cell center), the UE is not allowed to relax its neighbor cell measurements. This ensures that mobility does not have a negative impact on high mobility UEs, thus accepting the result that no power saving can be achieved. Meanwhile, the second relaxation criterion is naturally still applicable to UEs in other mobility states (e.g., low and medium mobility).

[0139] According to this first variant of the mitigation decision, a UE that is vehicular or supports URLLC also decides not to relax the neighbor cell measurements based on a second mitigation criterion.

[0140] Fig. 10, similar to Fig. 6, illustrates in a simplified exemplary manner the relationship between UE mobility state and serving cell quality and the neighboring cell measurements performed by the UE as a result of the mitigation decision of this first variant. The mitigation is exemplarily shown to be determined based on the serving cell quality, which can be considered as a parameter derived from one or a combination of radio measurement quantities (e.g. RSRP, RSRQ or SINR, etc.). The low mobility state and the medium mobility state are shown together on the x-axis of Fig. 10 for ease of explanation. As is clear from the figure, a high mobility UE has no opportunity to save power by mitigating neighboring cell measurements, since the second mitigation criterion does not apply to high mobility UEs (see the explanation of the first variant) and, even if applied additionally, the first mitigation criterion is likely not met since the UE is in a high mobility state (the serving cell signal strength changes frequently and continuously). On the other hand, measurement relaxation is still possible for UEs in low or medium mobility states, i.e. when the second relaxation criterion is met, here in FIG. 10, for example, when the serving cell radio quality (which is one or a combination of RSRP, RSRQ, SINR) exceeds the corresponding threshold S1.

[0141] According to a second variant of the relaxation decision, the second relaxation criterion introduced above (if one or more of the measured radio measurement quantities for the serving radio cell are greater than the respective quantity threshold) is made dependent on the mobility state of the UE as follows: In particular, the second relaxation criterion is based on a comparison of the measured radio measurement quantities with the respective quantity thresholds. According to this second variant of the relaxation decision, the respective quantity thresholds may have different values ​​depending on the mobility state. This can be stated differently that different thresholds are applied depending on the mobility state.

[0142] For example, for a UE in a high mobility state, a first value is used for the quantity threshold of the second relaxation criterion, while for a UE in another mobility state (e.g., a low mobility state or a medium mobility state), a second value is used for the quantity threshold of the second relaxation criterion. The first value is greater than the second value of this quantity threshold, so that a UE in a high mobility state performs measurement relaxation only when the serving cell strength is exceptionally good (e.g., the UE is exactly in the cell center). Thus, a high mobility UE is less likely to relax neighbor cell measurements, which reduces the risk that the mobility of such a high mobility UE is adversely affected by measurement relaxation.

[0143] According to this second variant of the mitigation decision, the UEs mounted on vehicles or supporting URLLC also use the larger quantity threshold to decide whether to relax neighbor cell measurements based on the second mitigation criterion. Similarly, the coverage-extended UEs (CAT-M1) can use yet another different value of the quantity threshold S1 and / or S2, because the values ​​of S1 and S2 used for normal UEs are not suitable for coverage-extended UEs that can communicate reliably at significantly lower serving cell signal strengths. Correspondingly, the quantity thresholds S1_CE and S2_CE applied by the coverage-extended UEs can be smaller than the quantity thresholds S1 and S2 values ​​applied by other UEs, respectively.

[0144] The result of this exemplary second variant of the relaxation decision is illustrated in Fig. 11. Fig. 11 illustrates in a simplified exemplary manner the relationship between the UE mobility state and the serving cell quality and the resulting neighbor cell measurements performed by the UE. To simplify the figure, it is exemplarily assumed that the second relaxation criterion is determined based on only one radio measurement quantity (which is RSRP, RSRQ or SINR), so that one radio measurement quantity is compared with one appropriate quantity threshold. According to this second variant, the quantity threshold has two different values ​​S1 and S2, which are used depending on the mobility state of the UE. The first value S1 is used for the threshold by high mobility UEs and the second (smaller) value S2 is used for the threshold by low and medium mobility UEs.

[0145] The above second variant of the relaxation decision is illustrated in Fig. 11, based on a second relaxation criterion considering only one radio measurement quantity. However, conceptually, the second variant of the relaxation decision can also be applied in case the second relaxation criterion considers more than one radio measurement quantity, by providing different mobility state dependent values ​​for the respective quantity thresholds.

[0146] Moreover, the above second variant of the relaxed decision is illustrated in Fig. 11 based on the assumption of having only two different values ​​for one quantity threshold, here one for high mobility UEs and the other for UEs in the remaining mobility states, however conceptually the second variant of the relaxed decision can also be applied in the case of identifying more mobility states by correspondingly providing one quantity threshold for each mobility state to be identified.

[0147] Instead of making the second relaxation criterion introduced above (when one or more of the radio measurement quantities measured for the serving radio cell are greater than the respective quantity threshold) strictly dependent on the mobility state of the UE, a further solution of the improved measurement procedure relies on the concept of relaxed radio measurement requirements mentioned above. Such a solution decides whether to relax neighbor cell measurements based on the second relaxation criterion in the same way for all UEs, regardless of their mobility state. However, how to relax neighbor cell measurements depends on the mobility state of the UE. For example, a UE in a high mobility state does not relax neighbor cell measurements completely (e.g., does not perform neighbor cell measurements at all), but rather performs neighbor cell measurements according to relaxed radio measurement requirements, e.g., by performing neighbor cell measurements less frequently (see above description on relaxed measurement requirements). On the other hand, low mobility UEs and medium mobility UEs do not perform neighbor cell measurements at all when deciding to relax neighbor cell measurements.

[0148] The result of this solution is illustrated in Fig. 12, which illustrates in a simplified exemplary manner the relationship between UE mobility state and serving cell quality and the resulting neighbor cell measurements performed by the UE. The relaxation is exemplarily shown to be determined based on the serving cell quality, which can be considered as a parameter derived from one or a combination of radio measurement quantities (e.g. RSRP, RSRQ, or SINR, etc.). The low and medium mobility states are illustrated together on the x-axis of Fig. 12 for ease of illustration. As is evident from the figure, a high mobility UE will have the opportunity to relax neighbor cell measurements based on the relaxed radio measurement requirements, rather than not performing neighbor cell measurements at all as is applicable for low and medium mobility UEs. This nevertheless allows a high mobility UE to reduce power consumption while still limiting the negative impact of measurement relaxation on the UE's mobility.

[0149] The above variants and solutions presented in relation to Figures 10, 11 and 12 optimize the measurement relaxation for high mobility UEs to ensure that mobility is not adversely affected, for example, at the expense of power saving opportunities in that respect. Compared to the measurement procedure envisaged for Figure 6, the above variants and solutions of Figures 10, 11 and 12 offer different advantages and disadvantages. For example, the solution of Figure 10 has the least adverse effect on the mobility of high mobility UEs, but cannot provide power saving opportunities for high mobility UEs. The solution of Figure 11 takes the risk of adversely affecting the mobility of high mobility UEs in exchange for giving them power saving opportunities only when they experience very good signal strength from the serving cell. Furthermore, the solution of Figure 12 offers great flexibility to find a configurable trade-off between power saving and managing the adverse impact on the mobility of high mobility UEs, by appropriately defining the relaxed radio measurement requirements that the UE must follow when deciding to relax neighbor cell measurements.

[0150] While the above solutions presented in relation to Figures 10, 11 and 12 focus on optimizing the mitigation procedures for high mobility UEs, the following solution focuses on optimizing the mitigation procedures for low mobility UEs. For example, for UEs in a low mobility state, an additional second quantity threshold is defined for the second mitigation criterion, having a value smaller than the first quantity threshold already mentioned above. Such additional second quantity threshold does not need to be used for medium mobility UEs or for high mobility UEs.

[0151] As a result, the low mobility UE compares the measured signal strength of the serving cell to two thresholds to decide whether and how to relax the neighbor cell measurements. In particular, if the signal strength of the serving radio cell is greater than this second, smaller quantity threshold, but still less than the known quantity threshold, the UE decides to relax the neighbor cell measurements by performing neighbor cell measurements according to the relaxed radio measurement requirements (see above for details regarding the relaxed measurement requirements). If the UE determines that the signal strength is greater than the first, larger quantity threshold (and thus greater than the second quantity threshold), it may decide to relax the neighbor cell measurements to a greater extent and not perform neighbor cell measurements at all.

[0152] The result of this solution is shown in Fig. 13, which illustrates in a simplified exemplary manner the relationship between the mobility state of the UE and the serving cell quality and the resulting neighbor cell measurements performed by the UE. For ease of explanation, medium and high mobility UEs are shown together in Fig. 13. As is evident from the figure, the mitigation opportunities are different for low mobility UEs, which can already perform measurement mitigation at an additional second threshold (here S3 in Fig. 13). Thus, low mobility UEs can save more power.

[0153] The above solution illustrated in Fig. 13 is based on the second relaxation criterion considering only one radio measurement quantity, however, conceptually this solution can also be applied in the case where the second relaxation criterion considers more than one radio measurement quantity by providing different second quantity thresholds for each measurement quantity.

[0154] Furthermore, the above solution illustrated in Figure 13 is based on the assumption of having only one additional quantity threshold for low mobility UEs, but conceptually, this solution can also be applied to more mobility states by correspondingly providing an additional second quantity threshold for each mobility state in addition to the respective first quantity threshold.

[0155] The optimization of measurement mitigation for high mobility UEs has been described in relation to Fig. 10, Fig. 11 and Fig. 12, while Fig. 13 has been used to describe the optimization method of measurement mitigation for low mobility UEs. These optimizations above have been described individually and as standalone. However, these two optimization schemes can also be combined to provide an optimized measurement mitigation procedure for both low and high mobility UEs. Fig. 14 shows a combination of the solution presented in relation to Fig. 10 and the solution presented in relation to Fig. 13. Thus, as is evident from the figure, neighbor cell measurement mitigation is not provided for high mobility UEs, but for medium mobility UEs experiencing a serving cell quality higher than threshold S1, and also for low mobility UEs experiencing a serving cell quality higher than threshold S3 (here by performing neighbor cell measurements, but with relaxed requirements), and also for low mobility UEs experiencing a serving cell quality higher than threshold S1 (here by not performing neighbor cell measurements at all).

[0156] The UE behavior of such an exemplary implementation of such a combined solution is presented in Fig. 15. The UE behavior also takes into account the first relaxation criterion described above. According to this first relaxation criterion, relaxation is allowed for the UE when one or more of the measured radio measurement quantities for the serving radio cell changes below a threshold amount (referred to as V1 in Fig. 15) (not shown in Fig. 14) during the past period. As presented in the exemplary implementation of Fig. 15, the UE adapts the measurement relaxation procedure according to its mobility state, so as to realize that a high mobility UE does not perform measurement relaxation at all, a medium mobility UE performs measurement relaxation when the UE's serving cell quality exceeds a threshold S1, and a low mobility UE performs relaxation according to the UE's serving cell quality against two thresholds S1 and S3, where S1 is greater than S3.

[0157] A combination of the solutions presented with respect to FIG. 11 and FIG. 12, respectively, with the solution presented with respect to FIG. 13 is also possible.

[0158] Figures 16 and 17 show an exemplary implementation of the combination of the solutions of Figures 11 and 13. Figure 16 shows an overview of whether and how the UE performs neighbor cell measurement relaxation depending on the specific serving cell quality experienced by the UE and the mobility state of the UE. Similar to Figure 15, the illustrated UE behavior according to Figure 17 also takes into account the first relaxation criterion described above. According to this first relaxation criterion, relaxation is allowed for the UE when one or more of the measured radio measurement quantities for the serving radio cell have changed below a threshold amount (referred to as V1 in Figure 17) (not shown in Figure 16) during the past period. The UE behavior in Figure 17 shows the interdependence between the radio quality-based relaxation criterion and the mobility state of the UE to decide whether and how to relax the neighbor cell measurements. Correspondingly, it is realized that a high mobility UE performs measurement relaxation (indeed, does not perform measurements at all) only when the serving cell quality is very high (here, above the largest threshold S1). For medium mobility UEs, measurement relaxation is also provided by allowing the medium mobility UE to not perform neighbor cell measurements when the serving cell quality exceeds an intermediate threshold S2. Finally, if the UE is in a low mobility state, it is further determined whether the serving cell quality is below or above the smallest threshold S3. If so, the low mobility UE performs neighbor cell measurements without relaxation, if so (the previous check in FIG. 17 ensures that the serving cell quality is below S2), the low mobility UE can save power by using the relaxed requirements for neighbor cell measurements.

[0159] Figures 18 and 19 show an example implementation of the combination of the solutions of Figures 12 and 13. Figure 18 shows an overview of whether and how the UE performs neighbor cell measurement mitigation depending on the specific serving cell quality experienced by the UE and the mobility state of the UE. Similar to Figures 15 and 17, the illustrated UE behavior according to Figure 19 also takes into account the first mitigation criterion described above. According to this first mitigation criterion, mitigation is allowed for the UE when one or more of the measured radio measurement quantities for the serving radio cell have changed below a threshold amount (referred to as V1 in Figure 19) (not shown in Figure 18) during the past period. The UE behavior of Figure 19 (very similar to the UE behavior of Figure 15) shows the interdependence between the radio quality-based mitigation criterion and the mobility state of the UE to decide whether and how to relax neighbor cell measurements.

[0160] Correspondingly, the high mobility UE realizes relaxing the neighbor cell measurement by performing the neighbor cell measurement according to the relaxed measurement requirement when the serving cell quality is high enough, for example, when it exceeds the indicated threshold S1. The medium mobility UE can also relax the neighbor cell measurement when the serving quality exceeds the indicated threshold S1, in which case the medium mobility UE is allowed not to perform the neighbor cell measurement at all. Furthermore, for the low mobility UE, it is further determined whether the serving cell quality is below the smallest threshold S3 or above this threshold S3. If it is below, the low mobility UE performs the neighbor cell measurement without relaxation, and if it exceeds (the previous check in FIG. 19 ensures that the serving cell quality is below S1), the low mobility UE can save power by using the relaxed requirement for the neighbor cell measurement.

[0161] Furthermore, the UE may be required to perform different types of neighbor cell measurements, e.g., intra-frequency, inter-frequency, and inter-RAT measurements. The improved neighbor cell measurement method may be applied to all the different types of measurements separately, e.g., by deciding whether to relax each type of measurement separately and thus, e.g., by using different rules and thresholds for each type of neighbor cell measurement. Alternatively, the relaxation for all or a subset of these measurement types may be controlled together, e.g., by deciding jointly whether to relax some measurement types and thus, e.g., by using the same rules and thresholds.

[0162] One possible example implementation can be similar to that adopted for LTE, where the relaxation of inter-frequency neighbor cell measurements and inter-RAT neighbor cell measurements is subject to the same radio quality related measurement relaxation criteria (e.g., one or more radio measurement quantities Srxlev and Squal exceeding respective quantity thresholds S nonIntraSearchP , S nonIntraSearchQ ), whereas relaxation of intra-frequency neighbor cell measurements is determined using other radio quality related measurement relaxation criteria (e.g., whether one or more of the radio measurement quantities Srxlev and Squal exceed the respective quantity threshold S IntraSearchP , S IntraSearchQ is determined on an individual basis using the

[0163] In the above solution of the improved measurement method, it is assumed that the UE decides whether and how to relax the neighbor cell measurements by using certain parameters and thresholds. Typically, the UE is configured by the network (e.g., base station) on how to perform the neighbor cell measurements. Similarly, the thresholds (S1, S2, S3) can be determined in the same way by the base station and signaled to the UE, e.g., using a system information broadcast.

[0164] The above improved measurement procedure also includes determining the mobility state of the UE based on certain information and parameters, such as, for example, one or more thresholds for the number of cell reselections and the number of beam changes, fading conditions, and location information. Again, these thresholds can be configured by the base station for the UE and provided to the UE, for example, in system information broadcast by the base station in its cell.

[0165] Further Aspects

[0166] According to a first aspect, a user equipment (UE) is provided, the user equipment having a processor for determining one of a plurality of mobility states for the UE, the plurality of mobility states including at least three different mobility states. The processor determines one or more radio measurement quantities of a serving radio cell in which the UE is located. The processor decides whether to relax radio measurements on one or more neighboring radio cells based on the determined mobility state of the UE and the determined one or more radio measurement quantities of the serving radio cell. A receiver and the processor of the UE perform the radio measurements on the one or more neighboring radio cells according to radio measurement requirements if the processor determines not to relax the radio measurements on the one or more neighboring radio cells.

[0167] According to a second aspect provided in addition to the first aspect, if the processor decides to relax radio measurements on the one or more neighboring radio cells, the radio measurements on the one or more neighboring radio cells are not performed at all or are performed according to relaxed radio measurement requirements, which require the UE to perform radio measurements less frequently than according to the radio measurement requirements.

[0168] According to a third aspect provided in addition to the first or second aspect, the plurality of mobility states of the UE include a low mobility state, a medium mobility state, and a high mobility state. In an optional implementation, the determination of the mobility state of the UE by the processor is based on one or more of the following: Number of cell reselections in the past period, - Number of beam changes for the past period, Fading conditions regarding the serving cell's radio measurement quantities for the past period, location information of said UE for a past period of time; characteristics of the UE, e.g. that the UE is mounted on a vehicle, The type of said UE, for example a UE that supports Ultra-Reliable Low-Latency Communication (URLLC).

[0169] According to a fourth aspect provided in addition to one of the first to third aspects, the processor determines to relax the radio measurements on the one or more neighboring radio cells if one or more of a plurality of radio quality related measurement relaxation criteria are satisfied, the plurality of radio quality related measurement relaxation criteria comprising: a first radio quality related measurement relaxation criterion that is met when a change in one or more radio measurement quantities for the serving radio cell is less than a threshold quantity during a past time period; and a second radio quality related measurement relaxation criterion that is met when one or more radio measurement quantities for the serving radio cell are greater than a respective first quantity threshold; Includes.

[0170] According to a fifth aspect provided in addition to the fourth aspect, whether the second radio quality related measurement relaxation criterion is satisfied depends on the determined mobility state of the UE, wherein the second radio quality related measurement relaxation criterion is not satisfied for a UE determined to be in a high mobility state.

[0171] According to a sixth aspect provided in addition to the fourth aspect, for UEs determined to be in a high mobility state, a first value is applied to the first quantity threshold for the second radio quality related measurement relaxation criterion, and for UEs in a remaining mobility state, a second value is applied to the first quantity threshold for the second radio quality related measurement relaxation criterion, the first value of the first quantity threshold being greater than the second value of the first quantity threshold.

[0172] According to a seventh aspect provided in addition to the fourth aspect, for a UE determined to be in a high mobility state, when the second radio quality related measurement relaxation criterion is satisfied, the UE performs the radio measurements on the one or more neighboring radio cells according to a relaxed radio measurement requirement, the relaxed radio measurement requirement requiring the UE to perform radio measurements less frequently than according to the radio measurement requirement. In an optional implementation, for a UE determined to be in a low mobility state or a medium mobility state, when the second radio quality related measurement relaxation criterion is satisfied, the UE does not need to perform the radio measurements on the one or more neighboring radio cells.

[0173] According to an eighth aspect, provided in addition to one of the first to seventh aspects, for a UE determined to be in a low mobility state, a second quantity threshold is defined for the second radio quality related measurement relaxation criterion. If the one radio measurement quantity of the serving radio cell is greater than the second quantity threshold and less than the first quantity threshold, the radio measurements are performed on the one or more neighboring radio cells according to a relaxed radio measurement requirement. The relaxed radio measurement requirement requires the UE to perform radio measurements less frequently than according to the radio measurement requirement. If the one radio measurement quantity of the serving radio cell is greater than the first quantity threshold, the radio measurements on the one or more neighboring radio cells are not performed.

[0174] According to a ninth aspect provided in addition to any one of the first to eighth aspects, the measurements on the one or more neighboring radio cells are each one of different types: an intra-frequency measurement type, an inter-frequency measurement type, and an inter-radio access technology measurement type, and the decision whether to relax radio measurements on the one or more neighboring radio cells is performed separately for each type of neighboring radio cell measurement or performed jointly for all or a subset of the types of neighboring radio cell measurements.

[0175] According to a tenth aspect provided in addition to any one of the first to ninth aspects, the one or more radio measurement quantities include one or more of the following: Reference Signal Received Power (RSRP) quantity, Reference Signal Received Quality (RSRQ) quantity, and Signal-to-Interference plus Noise Ratio (SINR) quantity.

[0176] According to an eleventh aspect, there is provided a method comprising the following steps executed by a user equipment (UE): determining a mobility state from among a plurality of mobility states for the UE, the plurality of mobility states including at least three different mobility states; determining one or more radio measurement quantities for a serving radio cell in which the UE is located; determining whether to relax radio measurements on one or more neighbouring radio cells based on the determined mobility state of the UE and the determined one or more radio measurement quantities for the serving radio cell; if the UE determines not to relax radio measurements on the one or more neighbouring radio cells, performing the radio measurements on the one or more neighbouring radio cells according to radio measurement requirements.

[0177] According to a twelfth aspect, provided in addition to the eleventh aspect, if it is decided to relax the radio measurements on the one or more neighbouring radio cells, the radio measurements on the one or more neighbouring radio cells are not performed at all or are performed in accordance with relaxed radio measurement requirements, which require the UE to perform radio measurements less frequently than in accordance with the radio measurement requirements.

[0178] According to a thirteenth aspect provided in addition to the eleventh or twelfth aspects, the determining step determines to relax the radio measurements on the one or more neighboring radio cells if one or more of a plurality of radio quality related measurement relaxation criteria are satisfied, the plurality of radio quality related measurement relaxation criteria comprising: a first radio quality related measurement relaxation criterion that is met when a change in one or more radio measurement quantities for the serving radio cell is less than a threshold quantity during a past time period; and a second radio quality related measurement relaxation criterion that is met when one or more radio measurement quantities for the serving radio cell are greater than a respective first quantity threshold; Includes.

[0179] According to a fourteenth aspect provided in addition to the thirteenth aspect, whether the second radio quality related measurement relaxation criterion is satisfied depends on the determined mobility state of the UE, wherein the second radio quality related measurement relaxation criterion is not satisfied for a UE determined to be in a high mobility state.

[0180] According to a fifteenth aspect provided in addition to the thirteenth aspect, for UEs determined to be in a high mobility state, a first value is applied to the first quantity threshold for the second radio quality related measurement relaxation criterion, and for UEs in a remaining mobility state, a second value is applied to the first quantity threshold for the second radio quality related measurement relaxation criterion, the first value of the first quantity threshold being greater than the second value of the first quantity threshold.

[0181] Hardware and Software Implementations of the Disclosure

[0182] The present disclosure can be realized by software, hardware, or software in cooperation with hardware. Each functional block used in the description of each embodiment above can be realized partially or entirely by an LSI such as an integrated circuit, and each process described in each embodiment can be controlled partially or entirely by the same LSI or a combination of LSIs. The LSI may be formed as an individual chip, or one chip may be formed to include some or all of the functional blocks. The LSI may include a data input and a data output connected thereto. Here, the LSI may be called an IC, a system LSI, a super LSI, or an ultra LSI depending on the degree of integration. However, the technology for implementing the integrated circuit is not limited to the LSI, and may be realized using a dedicated circuit, a general-purpose processor, or a dedicated processor. In addition, a field programmable gate array (FPGA) that can be programmed after the LSI is manufactured, or a reconfigurable processor that can reconfigure the connection and settings of the circuit cells arranged inside the LSI may be used. The present disclosure can be realized as digital processing or analog processing. If future integrated circuit technologies replace LSI as a result of advances in semiconductor technology or other derived technologies, the future integrated circuit technologies can be used to integrate the functional blocks. Biotechnology is also applicable.

[0183] The present disclosure may be implemented by any type of apparatus, device, or system having communication capabilities, referred to as a communications apparatus.

[0184] The communication device may have a transceiver and processing / control circuitry. The transceiver may have a receiver and a transmitter and / or function as both a receiver and a transmitter. The transceiver may include an RF (radio frequency) module including an amplifier, an RF modulator / demodulator, etc., and one or more antennas as a transmitter and a receiver.

[0185] Some non-limiting examples of such communications 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 (digital audio / video players), wearable devices (e.g., wearable cameras, smart watches, tracking devices), game consoles, digital book readers, telehealth / telemedicine devices, vehicles (e.g., automobiles, airplanes, ships) that provide communications capabilities, and various combinations thereof.

[0186] Communications devices are not limited to being portable or mobile, but may include any type of apparatus, device, or system that is non-portable or fixed, such as, for example, smart home devices (e.g., appliances, lighting, smart meters, control panels), vending machines, or any other "things" in an "Internet of Things" network.

[0187] Communications may include, for example, the exchange of data via cellular systems, wireless LAN systems, satellite systems, and the like, as well as various combinations thereof.

[0188] A communications apparatus may have devices such as controllers or sensors connected to a communications device that performs the communications functions described in this disclosure. For example, a communications apparatus may have a controller or a sensor that generates control or data signals used by the communications device to perform the communications functions of the communications apparatus.

[0189] Communications equipment may also include infrastructure facilities, such as base stations, access points, or any other equipment, device, or system that communicates with or controls the equipment in the non-limiting examples above.

[0190] Furthermore, the various embodiments may be implemented by means of software modules, which are executed by a processor or directly in hardware. Also, a combination of software modules and hardware implementation is possible. The software modules can be stored on any kind of computer-readable storage medium, for example RAM, EPROM, EEPROM, flash memory, registers, hard disks, CD-ROM, DVD, etc. It should be noted that furthermore, individual features of the different embodiments may be the subject of another embodiment, individually or in any combination.

[0191] It will be apparent to those skilled in the art that various changes and / or modifications may be made to the present disclosure illustrated in the specific embodiments, and therefore the embodiments illustrated herein are to be considered in all respects as illustrative and not restrictive of the present invention.

Claims

1. 1. A communications device, comprising: a processor for determining, during operation, for each measurement period, at least one radio measurement quantity for at least one radio cell; A communications device, wherein a first scaling factor associated with a frequency range and a DRX cycle and a second scaling factor, the second scaling factor being a mitigation scaling factor, are adapted for the measurement period when at least one mitigation criterion is satisfied.

2. determining to perform relaxed radio measurements on the at least one radio cell when the at least one relaxed criterion is satisfied; performing the relaxed radio measurements less frequently than non-relaxed radio measurements; The communication device of claim 1 .

3. the at least one mitigation criterion is met when a change in at least one radio measurement quantity for the radio cell is less than a threshold quantity during a past period. The communication device of claim 1 .

4. When the communication device is in a non-cell edge, the mitigation factor is greater than 1. The communication device of claim 1 .

5. When the communication device is in a first mobility state, the mitigation scaling factor is greater than 1. The communication device of claim 1 .

6. the first mobility state is a low mobility state, and the second mobility state is a higher mobility state than the low mobility state.

6. A communication device as claimed in claim 5.

7. The processor's determination of the mobility state of the communication device is based on one or more of the following: - the number of cell reselections in the past period; - number of beam changes in the past period, - fading conditions regarding the serving cell's radio measurement quantities for the past period; - location information of the communication device for a past period of time; - characteristics of said communications device; - the type of said communication device; 6. A communication device as claimed in claim 5.

8. the radio measurements on the at least one radio cell are each one of different types: an intra-frequency measurement type, an inter-frequency measurement type, and an inter-radio access technology measurement type; - the decision on whether to relax radio measurements on the at least one radio cell is performed separately for each type of radio cell measurement or for all or a subset of types of radio cell measurements together. A communication device according to claim 1 or 2.

9. The at least one radio measurement quantity includes at least one of the following: Reference Signal Received Power (RSRP) quantity, Reference Signal Received Quality (RSRQ) quantity, and Signal-to-Interference plus Noise Ratio (SINR) quantity; The communication device of claim 1 .

10. 1. A method comprising the steps executed by a communications device, determining at least one radio measurement quantity for at least one radio cell for each measurement period, A method according to claim 1, wherein a first scaling factor associated with a frequency range and a DRX cycle and a second scaling factor, the second scaling factor being a relaxation scaling factor, are adapted to said measurement period when at least one relaxation criterion is satisfied.

11. determining to perform relaxed radio measurements on the at least one radio cell when the at least one relaxed criterion is satisfied; performing the relaxed radio measurements less frequently than non-relaxed radio measurements; The method of claim 10.

12. When the communication device is in a non-cell edge, the mitigation factor is greater than 1. The method of claim 10.

13. When the communication device is in a first mobility state, the mitigation scaling factor is greater than 1. The method of claim 10.

14. An integrated circuit for controlling processing of a communications device, the processing comprising: determining at least one radio measurement quantity for at least one radio cell for each measurement period; When at least one relaxation criterion is satisfied, a first scaling factor associated with a frequency range and a DRX cycle and a second scaling factor, the second scaling factor being a relaxation scaling factor, are adapted for the measurement period.

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