Apparatus and method for determining whether a user equipment is located in a registration area

Abstract

User equipment (UE), base stations, AMF (access and mobility management function) systems, and corresponding methods and integrated circuits are provided. The UE determines, based on signal strength measurements or location, in combination with either a dynamic cell's list of cell IDs and a mapping between timing or stored geographic regions and tracking areas, whether the UE is located in a registration area that has been indicated to the UE by an AMF, and the UE is paged in that registration area by a base station.

Description

Technical Field

[0001] This disclosure relates to the transmission and reception of signals in a communication system. Specifically, this disclosure relates to methods and apparatus for such transmission and reception. Background Technology

[0002] The 3rd Generation Partnership Project (3GPP) is dedicated to the technical specifications of next-generation cellular technologies, also known as fifth-generation (5G), which include “New Radio” (NR) radio access technology (RAT) operating in a frequency range up to 100 GHz. NR is a follower of technologies represented by Long Term Evolution (LTE) and LTE-A Advanced (LTE-A).

[0003] For systems like LTE, LTE-A, and NR, further modifications and selections can contribute to the efficient operation of the communication system and the specific devices associated with that system. Summary of the Invention

[0004] A non-limiting and exemplary embodiment facilitates efficient paging in NTN communication systems with earth-moving cells.

[0005] In the embodiments, the technology disclosed herein is characterized by a user equipment (UE) comprising:

[0006] transceiver

[0007] Send a registration request that includes at least one of the following:

[0008] • Indication of the UE's first position, or

[0009] • The cell ID of the last cell the UE has visited and the timestamp indicating the first instant the UE was in that last cell, and

[0010] Receive a registration acceptance message including an indication of a registration area, which includes the UE's first location, and

[0011] The circuit is based on the following:

[0012] • Cell IDs of multiple dynamic cells or cell sectors (sections) of dynamic cells

[0013] The list, the second-time indication of multiple dynamic cells forming a registration area, the coverage area information and satellite ephemeris data of the cell or cell sector indicating the coverage area of ​​each dynamic cell relative to the satellite position of the generating cell, and the measurement of the UE's second position, wherein the list of multiple dynamic cells and the second-time indication are included in the registration area indication, or

[0014] • A list of cell IDs, an indication of the time interval between multiple dynamic cells or cell sectors forming a registration area, and the cell ID of a newly accessed cell or cell sector, including the UE's second location and different from the last cell, wherein the list of cell IDs and the indication of the time interval are included in the indication of the registration area, or

[0015] • Measurement of the second location and mapping between the geographic area and the tracking area, and a list of one or more tracking areas forming the registered area, wherein the mapping is read from storage, and the list of one or more tracking areas is included in the indication of the registered area.

[0016] To determine whether the UE is in the registration area at the second location.

[0017] It should be noted that general or specific embodiments can be implemented as systems, methods, integrated circuits, computer programs, storage media, or any selective combination thereof.

[0018] Other benefits and advantages of the disclosed embodiments will become apparent from the specification and drawings. Benefits and / or advantages can be obtained individually from the various embodiments and features in the specification and drawings, and it is not necessary to provide all of these embodiments and features to obtain one or more such benefits and / or advantages. Attached Figure Description

[0019] In the exemplary embodiments described below, reference will be made to the accompanying drawings for more detailed description.

[0020] Figure 1 An exemplary architecture of a 3GPP NR system is shown;

[0021] Figure 2 This is a schematic diagram illustrating the functional separation between NG-RAN and 5GC;

[0022] Figure 3 This is a sequence diagram of the RRC connection establishment / reconfiguration process;

[0023] Figure 4 This is a schematic diagram illustrating the use cases of enhanced mobile broadband (eMBB), massive machine-type communications (mMTC), and ultra-reliable low-latency communications (URLLC);

[0024] Figure 5 This is a block diagram illustrating an exemplary 5G system architecture for non-roaming scenarios;

[0025] Figure 6 The registration process is shown;

[0026] Figure 7 The UE configuration update process is illustrated.

[0027] Figure 8 The NG setup process is shown;

[0028] Figure 9 The RAN configuration update process is illustrated.

[0029] Figure 10 This is a schematic diagram illustrating the relationship between the registration area, tracking area, and cell.

[0030] Figure 11 This illustrates a scenario of a non-terrestrial network (NTN), where transmissions between terminals are performed via remote radio units that include satellites and NTN gateways;

[0031] Figure 12 A scenario of a non-terrestrial network is shown, in which transmission between terminals is performed via satellite, including a gNB as a scheduling device;

[0032] Figure 13 This shows the mapping from a single cell (PCI) to multiple satellite beams;

[0033] Figure 14 This shows the mapping from a single cell (PCI) to a single satellite beam;

[0034] Figure 15 This illustrates a dynamic cell scenario in NTN;

[0035] Figure 16 The parameters of the ephemeris are shown;

[0036] Figure 17 This is a block diagram showing the AMF system, base station, and user equipment (UE);

[0037] Figure 18 This is a block diagram illustrating the RA location determination circuit for user equipment;

[0038] Figure 19 This is a flowchart of the communication methods of user equipment;

[0039] Figure 20 This is a flowchart of the communication method of the base station;

[0040] Figure 21 This is a flowchart of the AMF communication method;

[0041] Figure 22 The cell coverage area is indicated by the direction and diameter of the satellite beam.

[0042] Figure 23 The diagram shows an indication of cell coverage areas with non-overlapping shapes;

[0043] Figure 24 The cell coverage area is indicated by the distance from the cell center and within the coverage area;

[0044] Figure 25 This shows the definition of the tracking region as the union of cell regions at a given moment;

[0045] Figure 26 The registration and paging call process is shown;

[0046] Figure 27 It shows an indication of the tracking area through a list of cells at associated time intervals;

[0047] Figure 28 The registration and paging call process is shown;

[0048] Figure 29 The registration area is shown as defined by the restricted cell area;

[0049] Figure 30 The registration and paging call process is shown. Detailed Implementation

[0050] 5G NR System Architecture and Protocol Stack

[0051] 3GPP has been working on the next version of fifth-generation cellular technology (5G), including the development of a new radio access technology (NR) that operates in frequency ranges up to 100 GHz. The first version of the 5G standard was completed at the end of 2017, allowing for trials of 5G NR-compliant technology and commercial deployment on smartphones.

[0052] Among other things, the overall system architecture assumes NG-RAN (Next Generation Radio Access Network), which includes gNBs (gNodeBs) that provide NG-radio access user plane (SDAP / PDCP / RLC / MAC / PHY) and control plane (RRC radio resource control) protocols to the UE. The gNBs are interconnected via the Xn interface. The gNBs are also connected to the NGC (Next Generation Core) via the Next Generation (NG) interface, and more specifically, to the AMF (Access and Mobility Management Functions) (e.g., specific core entities performing the AMF) via the NG-U interface, and to the UPF (User Plane Functions) (e.g., specific core entities performing the UPF) via the NG-U interface. The NG-RAN architecture is as follows: Figure 1 As shown (for example, see Section 4 of 3GPP TS 38.300v15.6.0).

[0053] The NR user plane protocol stack (see, for example, Section 4.4.1 of 3GPP TS 38.300) includes PDCP (Packet Data Convergence Protocol, see Section 6.4 of TS 38.300), RLC (Radio Link Control, see Section 6.3 of TS 38.300), and MAC (Media Access Control, see Section 6.2 of TS 38.300) sublayers, which terminate at the gNB on the network side. Furthermore, a new Access Layer (AS) sublayer (SDAP, Service Data Adaptation Protocol) is introduced on top of PDCP (see, for example, Sub-clause 6.5 of 3GPP TS 38.300). A control plane protocol stack is also defined for NR (see, for example, Section 4.4.2 of TS 38.300). Sub-clause 6 of TS 38.300 provides an overview of Layer 2 functions. Sections 6.4, 6.3, and 6.2 of TS 38.300 list the functions of the PDCP, RLC, and MAC sublayers, respectively. The functions of the RRC layer are listed in Sub-clause 7 of TS 38.300.

[0054] For example, the media access control layer handles logical channel multiplexing, as well as scheduling and scheduling-related functions, including the processing of different parameter sets (numerology).

[0055] For example, the Physical Layer (PHY) is responsible for encoding / decoding, PHY HARQ processing, modulation, multi-antenna processing, and mapping signals to appropriate physical time-frequency resources. It also handles the mapping from 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 to transmit a specific transport channel, and each transport channel is mapped to a corresponding physical channel. For example, physical channels are PRACH (Physical Random Access Channel), PUSCH (Physical Uplink Shared Channel), and PUCCH (Physical Uplink Control Channel) for uplink, and PDSCH (Physical Downlink Shared Channel), PDCCH (Physical Downlink Control Channel), and PBCH (Physical Broadcast Channel) for downlink.

[0056] NR use cases / deployment scenarios can include enhanced mobile broadband (eMBB), ultra-reliable low latency communication (URLLC), and massive machine-type communication (mMTC), each with different requirements in terms of data rate, latency, and coverage. For example, eMBB is expected to support peak data rates (20Gbps downlink and 10Gbps uplink) and user experience rates approximately three orders of magnitude higher than IMT-Advanced. On the other hand, in the case of URLLC, ultra-low latency (0.5ms user plane latency for both UL and DL) and high reliability (1-10Gbps within 1ms) are crucial. -5This places more stringent requirements on mMTC. Finally, mMTC may preferably require high connection density (1,000,000 devices / km in urban environments). 2 ), wide coverage in harsh environments, and ultra-long battery life (15 years) for low-cost devices.

[0057] Therefore, an OFDM parameter set suitable for one use case (e.g., subcarrier spacing, OFDM symbol duration, cyclic prefix (CP) duration, number of symbols per scheduling interval) may not be suitable for another use case. For example, low latency services may preferably require shorter symbol durations (and therefore larger subcarrier spacings) and / or fewer symbols per scheduling interval (TTI) compared to mMTC services. Furthermore, deployment scenarios with large channel delay spreads may preferably require longer CP durations compared to scenarios with short delay spreads. Therefore, subcarrier spacing should be optimized to maintain similar CP overhead. NR can support more than one subcarrier spacing value. Accordingly, subcarrier spacings of 15kHz, 30kHz, 60kHz… are currently being considered. Symbol duration T… u The subcarrier spacing Δf is obtained through the formula Δf = 1 / T u Directly related. In a manner similar to that in LTE systems, the term "resource element" can be used to denote the smallest resource unit, which comprises one subcarrier of one OFDM / SC-FDMA symbol length.

[0058] In the new 5G-NR radio system, for each parameter set and carrier, resource grids for subcarriers and OFDM symbols are defined for both uplink and downlink. Each element in the resource grid is called a resource element and is identified based on its frequency index in the frequency domain and its symbol position in the time domain (see 3GPP TS 38.211 v15.6.0).

[0059] 5G NR Function Division between NG-RAN and 5GC

[0060] Figure 2 The functional partitioning between NG-RAN and 5GC is illustrated. NG-RAN logical nodes are either gNBs or ng-eNBs (next-generation eNBs). 5GC has logical nodes AMF, UPF, and SMF.

[0061] Specifically, gNB and ng-eNB host the following main functions:

[0062] - Functions for radio resource management, such as radio bearer control, radio access control, connection mobility control, and dynamic resource allocation (scheduling) of the UE in both uplink and downlink;

[0063] - Data IP header compression, encryption, and integrity protection;

[0064] - When the route to the AMF cannot be determined based on the information provided by the UE, select the AMF in the UE attachment;

[0065] - Routing of user plane data to (multiple) UPFs;

[0066] - Control plane information routing to AMF;

[0067] - Connection establishment and release;

[0068] - Scheduling and transmission of paging messages;

[0069] - Scheduling and transmission of system broadcast information (originating from AMF or OAM);

[0070] - Configuration for measurement and measurement reporting for mobility and scheduling;

[0071] -Transmission-level packet markings in the uplink;

[0072] -Session management;

[0073] -Support for network slicing;

[0074] - Mapping to data radio bearers and QoS flow management;

[0075] - Support for UEs in RRC_INACTIVE state;

[0076] - NAS (Non-access stratum) message distribution function;

[0077] - Radio access network sharing;

[0078] -Dual connection;

[0079] -Close interoperability between NR and E-UTRA.

[0080] The Access and Mobility Management Function (AMF) hosts the following key functions:

[0081] - Non-Access Stratum (NAS) signaling termination;

[0082] -NAS signaling security;

[0083] - Access Layer (AS) security controls;

[0084] - Signaling between 3GPP access networks for mobility between core network (CN) nodes; - Idle mode UE reachability (including control and execution of paging retransmission);

[0085] -Registration area management;

[0086] -Support for intra-system and inter-system mobility;

[0087] -Access authentication;

[0088] - Access authorization, including checks on roaming permissions;

[0089] - Mobility management controls (subscriptions and policies);

[0090] -Support for network slicing;

[0091] - Session Management Function (SMF) selection.

[0092] In addition, the User Plane Function (UPF) hosts the following main functions:

[0093] - Anchor points for movement within / between RATs (where applicable);

[0094] - External PDU session points for interconnection to the data network;

[0095] - Data packet routing and forwarding;

[0096] - Data grouping checks and user plane components for policy rule enforcement;

[0097] -Business usage report;

[0098] -Supports uplink classifiers that route service flows to the data network;

[0099] -Supports branch points for multi-homed PDU sessions;

[0100] - QoS processing for the user plane, such as packet filtering, gating, and UL / DL rate implementation;

[0101] - Uplink service verification (SDF to QoS flow mapping);

[0102] - Downlink packet buffering and downlink data notification triggering.

[0103] Finally, the Session Management Function (SMF) hosts the following main functions:

[0104] -Session management;

[0105] -UE IP address allocation and management;

[0106] -Selection and control of UP function;

[0107] - Configure service bootstrapping in User Plane Function (UPF) to route services to the correct destination;

[0108] - Part of the control policy implementation and QoS;

[0109] - Downlink data notification.

[0110] RRC connection establishment and reconfiguration process

[0111] Figure 3 This illustrates some interactions between the UE, gNB, and AMF (5GC entity) in the context of the UE's transition from RRC_IDLE to RRC_CONNECTED for the NAS portion (see TS 38.300 v15.6.0).

[0112] RRC is a higher-level signaling (protocol) used for UE and gNB configuration. Specifically, this transition involves the AMF preparing UE context data (including, for example, PDU session context, security keys, UE radio capabilities, and UE security capabilities) and sending it to the gNB along with 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 by the UE responding to the gNB with a SecurityModeComplete message. Afterward, the gNB performs reconfiguration by sending an RRCReconfiguration message to the UE and, in response, receiving an RRCReconfigurationComplete message from the UE to establish Signalling Radio Bearer 2 (SRB2) and (multiple) Data Radio Bearers (DRBs). For signaling-only connections, since SRB2 and DRBs are not established, the steps related to RRCReconfiguration are skipped. Finally, gNB notifies AMF that the setup process is complete using INITIAL CONTEXT SETUP RESPONSE.

[0113] Therefore, this disclosure provides an entity for a fifth-generation core (5GC) (e.g., AMF, SMF, etc.), which includes control circuitry for establishing a next-generation (NG) connection with the gNodeB; and a transmitter that sends an initial context establishment message to the gNodeB via the NG connection to initiate the establishment of a signaling radio bearer between the gNodeB and the user equipment (UE). Specifically, the gNodeB sends radio resource control (RRC) signaling containing resource allocation configuration information elements to the UE via the signaling radio bearer. The UE then performs uplink transmission or downlink reception based on the resource allocation configuration.

[0114] Use cases of IMT in 2020 and beyond

[0115] Figure 4 Some of the use cases for 5G NR are shown. In the 3rd Generation Partnership Project New Radio (3GPP NR), three use cases are considered, envisioned to support a wide variety of services and applications supporting IMT-2020. The first phase of the enhanced mobile broadband (eMMB) specification has been completed. In addition to further expanding eMMB support, current and future work will involve the standardization of ultra-reliable and low latency communication (URLLC) and massive machine-type communication. Figure 4 Examples of envisioned use cases for IMT in 2020 and beyond are shown (see, for example, ITU-R M.2083). Figure 2 ).

[0116] URLLC use cases have stringent requirements for capabilities such as throughput, latency, and availability, and are envisioned as one of the enablers for future vertical applications such as wireless control of industrial manufacturing or production processes, telemedicine surgery, distribution automation in smart grids, and transportation security. Ultra-reliability for URLLC is supported by identifying technologies that meet the requirements set forth in TR 38.913. For NR URLLC in Release 15, key requirements include a target user plane latency of 0.5 ms for UL (uplink) and 0.5 ms for DL ​​(downlink). A typical URLLC requirement for a single packet transmission is a user plane latency of 1 ms for a BLER (Block Error Rate) of 1E-5 with a packet size of 32 bytes.

[0117] From a physical layer perspective, reliability can be improved in a variety of ways. Current methods for enhancing reliability include defining a separate CQI table for URLLC, a more compact DCI (Downlink Control Information) format, and PDCCH repetition. However, as NR becomes more stable and developed, the scope for achieving ultra-reliability may expand (for critical requirements of NR). Specific use cases for NR URLCC in Rel.15 include augmented reality / virtual reality (AR / VR), eHealth, eSafety, and mission-critical applications.

[0118] Furthermore, the technical enhancements targeted by NR URLCC aim to improve latency and reliability. Enhancements for latency improvement include configurable parameter sets, slotless scheduling with flexible mapping, unlicensed (configured licensed) uplinks, slot-level repetition for data channels, and downlink pre-emption. Pre-emption means that a transmission that has already been allocated resources is stopped, and the allocated resources are used for another transmission that is requested later but has lower latency / higher priority requirements. Therefore, a licensed transmission is pre-empted by a subsequent transmission. Pre-emption applies independently of a specific service type. For example, a transmission of service type A (URLCC) may be pre-empted by a transmission of service type B (such as eMMB). Technical enhancements for reliability improvement include a dedicated CQI / MCS table for the target BLER of 1E-5.

[0119] The use cases for mMTC (massive machine-type communication) are characterized by a large number of connected devices typically sending relatively small amounts of non-latency-sensitive data. Device requirements include low cost and long battery life. From NR's perspective, utilizing a very narrow bandwidth segment is a possible solution, which, from the user equipment's perspective, can save power and extend battery life.

[0120] As mentioned above, the reliability range of NR is expected to become broader. A key requirement, essential for all cases and especially for URLLC and mMTC, is high or ultra-high reliability. Several mechanisms can be considered to improve reliability from both radio and network perspectives. Generally, there are a few key potential areas that can help improve reliability. These areas include compact control channel information, data / control channel repetition, and diversity in the frequency, time, and / or spatial domains. These areas generally apply to reliability regardless of the specific communication scenario.

[0121] For NR URLLC, further use cases with more stringent requirements have been identified, such as factory automation, the transportation industry, and power distribution. The more stringent requirement is higher reliability (up to 10). -6High availability, packet size up to 256 bytes, and time synchronization as low as a few μs, where the value can be one or a few μs depending on the frequency range and short latency of about 0.5 to 1 ms, particularly the target user plane latency of 0.5 ms, depending on the use case.

[0122] In addition, several technical enhancements have been identified for NR URLCC from a physical layer perspective. These include PDCCH enhancements related to compact DCI, PDCCH (Physical Downlink Control Channel) repetition, and increased PDCCH monitoring. Furthermore, UCI (Uplink Control Information) enhancements are associated with enhanced HARQ (Hybrid Automatic Repeat Request) and CSI feedback enhancements. PUSCH enhancements related to mini-slot-level hops and retransmission / repetition enhancements have also been identified. The term "mini-slot" refers to a Transmission Time Interval (TTI) that includes fewer symbols than a slot (a slot consisting of 14 symbols).

[0123] In slot-based scheduling or allocation, a slot corresponds to the time granularity (TTI - Transmission Time Interval) used for scheduling and allocation. Typically, the TTI determines the time granularity of the scheduling allocation. A TTI is the time interval during which a given signal is mapped to the physical layer. For example, traditionally, the TTI length can vary from 14 symbols (slot-based scheduling) to 2 symbols (non-slot-based scheduling). Downlink (DL) and uplink (UL) transmissions are specified as being organized into frames consisting of 10 subframes (1 millisecond duration) (10 millisecond duration). In slot-based transmissions, subframes are further divided into slots, the number of which is defined by the digital / subcarrier spacing. Specified values ​​range from 10 slots per frame (1 slot per subframe) for a 15 kHz subcarrier spacing to 80 slots per frame (8 slots per subframe) for a 120 kHz subcarrier spacing. For a normal cyclic prefix, the number of OFDM symbols per time slot is 14, and for an extended cyclic prefix, the number of OFDM symbols per time slot is 12 (see 3GPP TS 38.211 V15.3.0, Physical Channels and Modulation, 2018-09, Sections 4.1 (General Frame Structure), 4.2 (Parameter Set), 4.3.1 (Frames and Subframes), and 4.3.2 (Time Slots)). However, the allocation of time resources for transmission can also be non-time slot based. Specifically, in a non-time slot based allocation, the TTI can correspond to micro-slots instead of time slots. That is, one or more micro-slots can be allocated to the requested data / control signaling transmission. In a non-time slot based allocation, the minimum length of the TTI can be, for example, 1 or 2 OFDM symbols.

[0124] QoS control

[0125] The 5G QoS (Quality of Service) model is based on QoS flows and supports both QoS flows that require guaranteed flow bit rates (GBR QoS flows) and QoS flows that do not require guaranteed flow bit rates (non-GBR QoS flows). Therefore, at the NAS level, QoS flows represent the finest granularity of QoS differentiation within a PDU session. Within a PDU session, QoS flows are identified via the NG-U interface by the QoS Flow ID (QFI) carried in the encapsulation header.

[0126] For each UE, 5GC establishes one or more PDU sessions. For each UE, NG-RAN establishes at least one data radio bearer (DRB) along with the PDU session, and subsequently, additional DRBs for (multiple) QoS flows of that PDU session can be configured (when to do so depends on NG-RAN), for example, as referenced above. Figure 3 As shown, 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, while AS-level mapping rules in the UE and NG-RAN associate UL and DL QoS flows with DRBs.

[0127] Figure 5 A 5G NR non-roaming reference architecture is shown (see Section 4.23 of TS 23.501 v16.1.0). Application Functions (AFs) (e.g., managed...) Figure 4 The external application server (exemplary in the 5G services described herein) interacts with the 3GPP core network to provide services, such as supporting application-driven traffic routing, access network exposure functions (NEF), or interacting with the policy framework for policy control (see Policy Control Functions (PCF)), such as QoS control. Based on operator deployment, application functions deemed trusted by the operator may be allowed to interact directly with the relevant network functions. Application functions that the operator does not allow to directly access network functions may interact with the relevant network functions via the external exposure framework through the NEF.

[0128] Figure 5 Other functional units of the 5G architecture are illustrated, namely, 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), such as operator services, internet access, or third-party services. All or part of the core network functions and application services can be deployed and run in a cloud computing environment.

[0129] Therefore, this disclosure provides an application server (e.g., an AF for a 5G architecture) that includes a transmitter and control circuitry. The transmitter sends a request containing QoS requirements for at least one of the functions of 5GC (e.g., NEF, AMF, SMF, PCF, UPF, etc.) to at least one of the functions of 5GC, to establish a PDU session including a radio bearer between the gNodeB and the UE according to the QoS requirements. The control circuitry uses the established PDU session to perform services.

[0130] In LTE and NR, the terminal is referred to as a User Equipment (UE). This can be a mobile device or communication device with UE functionality, such as a cordless phone, smartphone, tablet, or USB (Universal Serial Bus) stick. However, the term mobile device is not limited to this; typically, a relay can also have the functionality of such a mobile device, and a mobile device can also function as a relay.

[0131] A base station is a network node or scheduling node, for example, part of a network used to provide services to terminals. A base station is a network node that provides wireless access to terminals.

[0132] Figures 6 to 9 It shows that for Figure 3 The example in the document provides some additional examples of the interaction between the AMF and the UE and NG-RAN nodes (e.g., gNB).

[0133] Specifically, Figure 6 The registration process is illustrated, in which a registration request is sent from the UE to the AMF, and in response, a registration acceptance message is sent by the AMF. For example, the UE initiates a registration process, such as for initial registration, mobility registration update, or periodic registration update.

[0134] On the other hand, for example, if the AMF wants to update the UE configuration for access and mobility-related parameters, the AMF can initiate a UE configuration update process, such as... Figure 7 As shown. Figure 7 As shown, the AMF sends a configuration update command, and the UE responds to the command with a configuration update complete message.

[0135] Figure 8 The diagram illustrates the NG establishment process between an NG-RAN node and an AMF. Specifically, the NG-RAN node (e.g., a gNB) sends an NG establishment request to the AMF and receives an NG establishment response from the AMF. The NG establishment process can be used to exchange application-level data (e.g., configuration data) required for proper interoperability between the NG-RAN node and the AMF on the NG interface.

[0136] In addition, the RAN configuration update process can be used to update the application-level configuration data required for proper interoperability between NG-RAN nodes and AMF on the NG interface. For example... Figure 9 As shown, the RAN configuration update process may include the NG-RAN node sending a RAN configuration update and receiving a RAN configuration update confirmation in response.

[0137] RRC status

[0138] In wireless communication systems including NR, devices or communication apparatuses (e.g., UEs) can be in different states depending on service activity. In NR, a device can be in one of three RRC states: RRC_IDLE, RRC_CONNECTED, and RRC_INACTIVE. The first two RRC states, RRC_IDLE and RRC_CONNECTED, are similar to their counterparts in LTE, while RRC_INACTIVE is a new state introduced in NR and did not exist in the original LTE design. There are also core network states CN_IDLE and CN_CONNECTED, depending on whether the device has established a connection with the core network.

[0139] In RRC_IDLE, there is no RRC context in the radio access network; that is, the parameters necessary for communication between the device and the network, and the device does not belong to a specific cell. From the core network's perspective, the device is in CN_IDLE state. Since the device spends most of its time in sleep mode to reduce battery consumption, data transmission may not occur. In the downlink, the idle device periodically wakes up to receive paging messages from the network (if any). Mobility is handled by the device through cell reselection. Uplink synchronization is not maintained, so the only uplink-only transmission activity that may occur is random access, such as transitions to a connected state. As part of the transition to a connected state, an RRC context is established in both the device and the network.

[0140] In RRC_CONNECTED, an RRC context is established, and all parameters required for communication between the device and the radio access network are known to both entities. From the core network's perspective, the device is in the CN_CONNECTED state. The cell to which the device belongs is known, and the device's identifier and Cell Radio Network Temporary Identifier (C-RNTI) for signaling purposes between the device and the network have been configured. The connected state is intended for data transmission to and from the device, but Discontinuous Reception (DRX) can be configured to reduce device power consumption. Because an RRC context is established in the gNB in ​​the connected state, leaving the DRX and starting to receive / transmit data is relatively fast, as connection establishment is not required for its associated signaling. Mobility is managed by the radio access network; that is, the device provides neighboring cell measurements to the network, and the network commands the device to perform a handover when relevant. Uplink time alignment may or may not be present, but it needs to be established and maintained using random access for data transmission.

[0141] In LTE, only idle and connected states are supported. In practice, it's common to use the idle state as the primary sleep state to reduce device power consumption. However, frequent small packet transmissions are common for many smartphone applications, resulting in numerous idle-to-active transitions in the core network. These transitions come at the cost of signaling load and associated latency. Therefore, to reduce signaling load and overall latency, a third state, the RRC_INACTIVE state, is defined in NR.

[0142] In RRC_INACTIVE, the RRC context is maintained simultaneously in both the device and the gNB. Core network connectivity is also maintained, meaning the device is in the CN_CONNECTED state from the core network's perspective. Therefore, the transition to the connected state for data transmission is rapid. No core network signaling is required. The RRC context is already in place in the network and idle-to-active transitions can be handled in the radio access network. Simultaneously, the device is allowed to sleep in a manner similar to that in the idle state and mobility is handled through cell reselection, i.e., without network involvement. Therefore, the mobility of the communication device or equipment is device-controlled, not network-controlled, and the communication device can contact the network via random access. Thus, RRC_INACTIVE can be viewed as a hybrid of idle and connected states (for further details, see E. Dahlman et al., 5G NR: Next Generation Radio Access, 1st Edition, Sections 6.5.1–6.5.3).

[0143] Paging process in 5G NR

[0144] Based on the current standard version, an exemplary implementation of paging functionality involving PDCCH monitoring in 5G NR will be explained below in simplified and abbreviated form.

[0145] In 5G NR, there are two different paging procedures: RAN-based paging (e.g., based on RAN-based notification areas) and core network-based paging (e.g., see 3GPP TS38.300v15.6.0, TS38.304v15.4.0 and TS 38.331v15.6.0, which mention RAN paging and CN paging in several sections, such as Section 9.2.5 "Paging" in TS38.300).

[0146] Paging allows the network to reach UEs in the RRC_IDLE and RRC_INACTIVE states via paging messages, and to notify UEs in the RRC_IDLE, RRC_INACTIVE, and RRC_CONNECTED states of system information changes and public warning information (such as ETWS / CMAS, earthquake and tsunami warning systems / commercial mobile alert systems) via short messages. Both paging messages and short messages are addressed using P-RNTI on the PDCCH monitored by the UE. However, when the actual paging message (e.g., with a paging record) is transmitted on the PCCH (as indicated by the PDCCH), the short message can be transmitted directly through the PDCCH.

[0147] When in RRC_IDLE, the UE monitors the paging channel for paging initiated by the CN; when in RRC_INACTIVE, the UE also monitors the paging channel for paging initiated by the RAN. However, the UE does not need to continuously monitor the paging channel; a paging DRX is defined, where a UE in RRC_IDLE or RRC_INACTIVE only needs to monitor the paging channel during one paging opportunity (PO) in each DRX cycle (see 3GPP TS 38.304v15.3.0, e.g., Sections 6.1 and 7.1). The paging DRX cycle is configured by the network.

[0148] For UEs paging initiated by the CN and paging initiated by the RAN, the POs are based on the same UE ID, resulting in overlapping POs. The number of distinct POs in a DRX cycle can be configured via system information, and the network can assign UEs to these POs based on their IDs. A PO is a set of PDCCH monitoring moments and can include multiple time slots (e.g., subframes or OFDM symbols) in which paging DCIs can be transmitted. A paging frame (PF) is a radio frame and can contain one or more POs or the start point of a PO.

[0149] When in RRC_CONNECTED, the UE monitors the paging channel in any PO signaled in the System Information (SI) change indication and / or PWS (Common Warning System) notification. In the case of Bandwidth Adaptation (BA) (see Section 6.10 of TS 38.300), the UE in RRC_CONNECTED only monitors the paging channel on the active BWP configured with a common search space.

[0150] When a UE receives a paging message, the UE can stop PDCCH monitoring. Depending on the paging reason, the UE can continue, for example, to obtain system information or establish an RRC connection with the base station and then receive services / instructions from the network.

[0151] Tracking region and tracking region code

[0152] Since the location of the UE is usually known at the cell level, paging messages are typically sent across multiple cells in a so-called Tracking Area (TA), which can be controlled by the AMF / MME (Mobility Management Entity).

[0153] A group of adjacent gNBs can be defined as a TA. This definition can be performed, for example, during the initial deployment of the network, where each gNB can be configured with its own TA. A Tracking Area Code (TAC) is a unique code assigned to each TA.

[0154] Since the network must have updated location information about UEs in RRC_IDLE in order to determine which TA a particular UE is in, the UE can notify the network of its current location by sending a Tracking Area Update (TAU) message each time it moves between TAs.

[0155] Therefore, when a UE connects to the network, it obtains a list of TAs indicating where the network believes the UE is located. When moving within a TA indicated by the list, a TAU procedure is not required. However, when the UE moves to a TA not indicated by the list, a TAU procedure is initiated.

[0156] Furthermore, UEs in RRC_IDLE state can periodically send TAU messages, even when the UE remains within the same TA. By periodically providing TAU messages, the network can be informed that the UE is still available and can receive data.

[0157] The tracking area code associated with a cell can be broadcast in the system information by the corresponding gNB.

[0158] Registration Area

[0159] As described above, a Tracking Area (TA) is used at the core network level (e.g., via the AMF) to track UE mobility in order to effectively page the UE when it is idle. Each UE is assigned a TAI (Tracking Area Identifier) ​​list (e.g., the TA list mentioned above) by the core network. Registered Region (RA) Typically, the registration area is UE-specific, and even in similar locations, it can be different for different UEs (e.g., for load balancing reasons).

[0160] When the core network needs to page a UE (e.g., when there is downlink data to be sent to the UE), the core network sends a paging message to one or more gNBs, and the gNBs or multiple gNBs perform paging of the UE on each cell belonging to the registered area.

[0161] Figure 10 The relationship between the registration area, tracking area, and cells is illustrated, where tracking areas TAI1 and TAI2 each contain multiple cells. For example, the registration area assigned to a UE could be registration area = {TAI1, TAI2}. In this example, the gNB serves a single cell. However, this disclosure is not limited to the specific relationship between the gNB (or base station) and cells, and the gNB may also serve multiple cells.

[0162] When a UE moves to a cell outside the area defined by the RA, it needs to access the network and perform a mobility registration update process. During the mobility update process, it can use... Figure 6 As shown in the registration process, the UE reports its TAI to the network via a REGISTRATIONREQUEST message. The core network then provides the UE with a new list of TAIs, including the new TAIs, in a REGISTRATION ACCEPT message. Therefore, the UE is assigned a new registration region.

[0163] Therefore, when moving to a new cell, the UE needs to determine if it is still within the same RA. To determine if it is still within the same RA, the UE considers the TAC associated with that cell. Each cell broadcasts its associated TAC (Tracking Area Code of the TA to which the cell belongs) and PLMN ID (Public Land Mobile Network Identifier) ​​in its system information (e.g., SIB1, System Information Block 1). When the UE visits or camps on a new cell, it reads the system information to derive the TAI by concatenating the TAC and PLMN ID or by appending the TAC to the PLMN ID (TAI = PLMN ID + TAC). The UE then compares the derived TAI with the list of TAIs in the RA. Here, "camping" on a cell includes at least one of initiating monitoring paging, reading the SIB from the cell, and performing measurements using the RS from the cell.

[0164] Non-terrestrial networks (NTN)

[0165] In 3GPP, NR-based operations in non-terrestrial networks (NTNs) are studied and described (see, for example, 3GPP TR 38.811, Research on New Radio (NR) Supporting Non-Terrestrial Networks, version 15.2.0, and 3GPP TR 38.821, NR Solutions Supporting Non-Terrestrial Networks, version 16.0.0).

[0166] Due to the extensive service coverage capabilities of space / airborne vehicles and their reduced vulnerability to physical attacks and natural disasters, NTN can facilitate the deployment of NR services in unserved areas not covered by terrestrial NR networks (e.g., isolated or remote areas, on aircraft or ships) and unserved regions (e.g., suburban and rural areas). Furthermore, NTN can enhance the reliability of NR services by providing service continuity for passengers at mobile stations or ensuring service availability anywhere, especially for critical communications.

[0167] These benefits involve standalone non-terrestrial networks or integrated terrestrial and non-terrestrial networks, which can affect coverage, user bandwidth, system capacity, service reliability, or availability.

[0168] For example, non-terrestrial networks refer to networks or network segments that use RF resources on satellites. NTN is typically characterized by the following system elements: NTN terminals, which can refer to 3GPP UEs or, in the case where the satellite does not directly serve 3GPP UEs, satellite-specific terminals; serving links, which refer to the radio links between user equipment and space / air platforms; air platforms carrying payloads; gateways connecting space / air platforms to the core network; and feeder links, which refer to the radio links between gateways and space / air platforms.

[0169] Figure 11 This illustrates a non-terrestrial network scenario where transmissions between terminals (UEs) are performed via a remote radio unit comprising a satellite and an NTN gateway. The gNB, located at the gateway, acts as a scheduling device. The satellite payload performs frequency conversion and RF amplification in both the uplink and downlink directions. Therefore, the satellite repeats the NR radio interface from the feeder link (between the NTN gateway and the satellite) to the service link (between the satellite and the UE), and vice versa. This configuration of satellite is referred to as a transparent satellite.

[0170] Figure 12 The diagram illustrates a non-terrestrial network scenario where transmissions between terminals (UEs) are performed via satellites, including gNBs acting as scheduling devices. This configuration of satellites is referred to as regenerative satellites.

[0171] Within an NTN, there may be different types of platforms, including satellite and UAS (Unmanned Aerial Systems) platforms, examples of which are listed in Table 1 (corresponding to Table 4.1-1 of 3GPP TR 38.821, see also 3GPP TR 38.821, Section 4.1, Overview of Non-Terrestrial Networks):

[0172]

[0173] Table 1: Types of NTN Platforms

[0174] For LEO, MEO, and HEO satellites that do not maintain a fixed position relative to a given point on Earth, the satellite beam corresponding to the cell or PCI (Physical Cell ID) or SSB (Synchronization Block) beam of the NR radio system can move on Earth.

[0175] Regarding the mapping between satellite beams, NR cells, and NR SSB beams, different deployment options can be considered, for example, Figure 13 and Figure 14 Options a and b are shown. According to... Figure 13 The deployment option a shown here, a cell (corresponding to a PCI with multiple satellite beams (e.g., the same PCI for multiple satellite beams), while according to Figure 14 As shown in deployment option b, one cell corresponds to one satellite beam (each satellite beam has one PCI).

[0176] A satellite beam can include one or more SSB beams. For example, a satellite beam can be mapped to an SSB beam; there is a one-to-one correspondence between satellite beams and SSB beams. The beam used to transmit NR synchronization signal blocks is called the SSB beam. An NR cell (PCI) can have up to L SSB beams, where L can be 4, 8, or 64, depending on the frequency band. The SSB beam can be used as a reference beam for beam management in NR.

[0177] An NTN scenario that provides continuously moving cells on Earth (e.g., NTN based on LEO, MEO, or HEO) is called a dynamic cell scenario. Figure 15 The scenario of dynamic cells is illustrated. Continuous cell movement on Earth is due to the operation where the satellite beams are fixed relative to the NTN platform. Therefore, depending on the deployment options a and b described above, the coverage area of ​​a cell that may correspond to several satellite beams or one satellite beam may vary depending on the NTN platform (e.g., such as...). Figure 15 The motion of the LEO satellite (as shown) is sliding on the Earth's surface.

[0178] Information about a satellite's orbital trajectory is contained in ephemeris data (or "satellite ephemeris data"). Ephemeris data can be represented in different ways, one of which is using orbital parameters such as semi-major axis, eccentricity, inclination, right ascension of the ascending node, argument of periapsis, mean anomaly at a reference time, and epoch. The first five parameters determine the orbital plane (orbital plane parameters), and the other two are used to determine the precise position of the satellite at a given time (satellite-level parameters). The orbital plane parameters and satellite-level parameters are listed in Table 2 and... Figure 16 This is illustrated (see also Section 7.3.6.1 of 3GPP TR 38.821V16.0.0, Representation of Complete Ephemeris Data). Another possible option is to provide the coordinates (x, y, z) of the satellite position, the velocity vector (vx, vy, vz), and the time reference point.

[0179]

[0180] Table 2: Ephemeris Elements

[0181] Therefore, representing ephemeris data may require seven parameters (e.g., double-precision floating-point numbers) and may incur some overhead. In an NTN system, several satellites can share a common orbital plane. In this case, some ephemeris data can be provided for the orbital plane instead of individual satellites to reduce the data volume. Ephemeris data for each orbital plane can be stored in the UE or in the UE's Subscriber Identity Module (SIM).

[0182] However, for networks with many satellites, the size of ephemeris data can be quite large. Therefore, ephemeris data can be sent at least partially from the gNB, rather than being stored.

[0183] For example, satellite-level orbital parameters for all satellites serving the UE can be stored in the UE or SIM, and the ephemeris data for each satellite is linked to a satellite ID or index. The satellite ID or index of the serving satellite can then be broadcast in system information, allowing the UE to find the corresponding ephemeris data in its SIM or storage device.

[0184] Alternatively, the satellite-level orbital parameters of the serving satellite can be broadcast in the system information, and the UE will derive the position coordinates of the serving satellite. Ephemeris data of neighboring satellites can also be provided to the UE via system information or dedicated RRC signaling. If the baseline orbital plane parameters are provided in the UE or SIM, broadcasting the mean anomaly at the reference time and the epoch to be broadcast to the UE may suffice, thus reducing overhead.

[0185] As per the above reference Figure 15The dynamic cell scenario described above provides an NTN scenario with continuously moving cells on Earth. This is because the satellite beam is operated with a fixed position relative to the NTN platform. Therefore, the coverage area of ​​the satellite beam slides across the Earth's surface as the NTN platform (e.g., a LEO satellite) moves.

[0186] As mentioned above, there is a correlation between the cell and the tracking area. However, in a dynamic cell scenario, if the TAC broadcast by the cell does not change, this means that the TA sweeps across the ground as the cell moves. For such a moving tracking area, even a stationary UE must continue to perform frequent registration updates, which incurs additional overhead and power consumption.

[0187] For these reasons, a fixed tracking area can be considered for NTN, rather than a mobile tracking area. Therefore, the tracking area corresponds to a fixed geographical location on Earth. For mobile cells, a fixed tracking area (TA) can be implemented in two ways: One method involves the TAC broadcast by the (mobile) cell changing as the cell covers different geographical areas. Another method involves the TAC not being broadcast, and the UE obtaining its registration area from other means (e.g., from its location information).

[0188] Regarding the mapping between cells and tracking areas, the options of "hard handover" and "soft handover" can be considered. Hard handover means that a cell broadcasts only one TAC per PLMN. When a new TAC replaces an old TAC in a cell, there may be some fluctuations in the boundary area between TACs. On the other hand, in the "soft handover" option, a cell can broadcast more than one TAC per PLMN. In addition to the old TAC, the cell also adds the new TAC to its system information and removes the old TAC later. However, the signaling of more TACs may lead to increased overhead (for hard handover and soft handover, see also 3GPP TR38.821, V16.0.0 (2019-12), Technical Specification Group Radio Access Networks; NR Solution for Supporting Non-Terrestrial Networks (NTN), Section 7.3.1.3.1).

[0189] The following describes some details regarding location-based TA determination. In particular, it can be considered that the Earth can be derived into multiple geographic regions corresponding to the TA. The mapping rules between geographic regions and their associated TAC values ​​can be further maintained in the UE and the network.

[0190] For example, during initial registration, the UE derives its TAC based on its location information and mapping rules, and then forms a TAI based on the derived TAI and the broadcast PLMN ID. The UE then reports the TAI to the AMF via a REGISTRATION REQUEST message. The AMF then provides the UE with a list of TAIs, including the reported TAIs, via a REGISTRATION ACCEPT message.

[0191] When a UE moves to a new geographic area, it derives a TAC based on its location information and mapping rules, and then forms a TAI based on the TAC and the broadcast PLMN ID. If the formed TAI is not in the TAI list, a mobile registration update process is triggered. In this process, the UE reports the TAI to the AMF via a REGISTRATION REQUEST message. The AMF provides the UE with a TAI list including the reported TAI via a REGISTRATION ACCEPT message. The UE then replaces the old TAI list with the new list including the reported TAI (see also 3GPP TR 38.821, V16.0.0 (2019-12), Technical Specification Group Radio Access Network; NR Solution for Supporting Non-Terrestrial Networks (NTN), Section 7.3.1.3.2).

[0192] Regarding the aforementioned TA determination mechanism, it is generally unclear how the mapping rules between geographic areas and TACs are available at the UE. Furthermore, as a specific example, if cell selection or reselection is based on radio signal strength, but the TAC is not broadcast, it is unclear how the UE determines that it is still in the RA, for example, if location functionality is unavailable.

[0193] Furthermore, due to the mobile nature of the cell, there is no fixed relationship between the calling and registration areas. When the core network needs to page a UE, it is unclear what information is required and how to obtain such information so that the AMF can select (multiple) gNBs to deliver the paging message, and the gNBs can select (multiple) cells to page the UE.

[0194] This disclosure pertains to tracking area determination and paging processing for non-terrestrial networks.

[0195] In this disclosure, a new radio access technology envisioned for 5G mobile communication systems such as 3GPP NR is described, along with a UE and a scheduling node such as a base station, and a corresponding method, but it can also be used in LTE mobile communication systems.

[0196] Therefore, a communication device (or user terminal or communication terminal) is called a UE (user equipment), and a scheduling node such as a base station can correspond to a gNodeB (gNB).

[0197] Furthermore, some terms used hereinafter, such as procedures, entities, and layers, are closely related to those used in LTE / LTE-A systems or in the current 3GPP 5G standardization, even though specific terms used in the context of new radio (NR) access technologies in the next 3GPP 5G communication system have not yet been fully determined or may ultimately change. Therefore, terminology may change in the future without affecting the functionality of the embodiments. Consequently, those skilled in the art will understand that, due to the lack of updated or ultimately agreed-upon terminology, the embodiments and their scope of protection should not be limited to the specific terminology exemplarily used herein.

[0198] Communication devices or equipment such as UEs, as well as scheduling nodes or base stations, may include transceivers and circuitry such as processing circuitry. A transceiver may further include and / or act as both a receiver and a transmitter. The processing circuitry may be one or more hardware pieces, such as one or more processors or any LSI (Large-Scale Integrated Circuit). There are input / output points (or nodes) between the transceiver and the processing circuitry, through which the processing circuitry can control the transceiver, i.e., control the receiver and / or transmitter and exchange received / transmitted data. As a transmitter and receiver, the transceiver may include an RF (Radio Frequency) front end, which includes one or more antennas, amplifiers, RF modulators / demodulators, etc. The processing circuitry can perform control tasks, such as controlling the transceiver to transmit user data and control data provided by the processing circuitry, and / or receiving user data and control data further processed by the processing circuitry. The processing circuitry may also be responsible for performing other processes, such as determination, decision-making, calculation, measurement, etc. The transmitter may be responsible for performing the transmission process and other related processes. The receiver may be responsible for performing the reception process and other related processes, such as monitoring the channel.

[0199] Communication devices such as UEs and base stations, as well as core network entities such as AMF systems, may include circuitry, which may include processing circuitry and control circuitry.

[0200] A user equipment UE 1770 is provided. For example... Figure 17 As shown, the UE includes a transceiver 1780 that sends a registration request. The registration request (or "registration request message") includes at least one of the following:

[0201] • Indication of the UE's first position, or

[0202] • The cell ID of the last cell the UE has visited and the timestamp indicating the first moment the UE was in the last cell.

[0203] The transceiver 1780 (or “UE transceiver”) of UE 1770 receives a registration acceptance message that includes an indication of a registration area (RA), wherein the registration area includes the UE’s first location.

[0204] UE 1770 also includes circuitry 1790 (or “UE circuitry”) which determines whether the UE is located in the registration area at the second position. The determination of whether the UE is in the registration area is based on at least one of the following:

[0205] • A list of cell IDs for multiple dynamic cells or cell sectors of dynamic cells; an indication of the second time when multiple dynamic cells form a registration area; coverage area information indicating the coverage area of ​​each dynamic cell or cell sector relative to the satellite position of the satellite that generated the cell, and the ephemeris data of that satellite; and a measurement of the UE's second position. The list of multiple dynamic cells and the indication of the second time are included in the indication of the registration area, or

[0206] • A list of cell IDs, an indication of the time interval between multiple dynamic cells or cell sectors forming the registration area, and the cell ID of the newly accessed cell or cell sector, including the UE's second location and different from the last cell. The cell ID list and the time interval indication are included in the registration area indication, or

[0207] • Measurement of the second location and mapping between the geographic area and the tracking area, and a list of one or more tracking areas forming the registered area, wherein the mapping is read from a storage device, and the list of one or more tracking areas is included in the indication of the registered area.

[0208] User equipment 1770 is a mobile device, communication device, or mobile terminal of a wireless communication system.

[0209] For example, UE circuit 1790 may include RA position determination circuit 1795. Figure 18 An exemplary RA position determination circuit 1795 is shown, including RA determination circuit 1896 and RA determination circuit 1897.

[0210] Figure 17 The diagram also shows and further provides a base station 1740. Base station 1740 includes an interface 1755 (also referred to as a "base station interface") that receives paging requests for paging a UE. The paging request includes an indication of a registration area. The base station also includes circuitry 1760 ("base station circuitry") based on the following:

[0211] • A list of cell IDs for the first plurality of dynamic cells or cell sectors of dynamic cells, an indication of the time when the first plurality of dynamic cells form a registration area, and coverage area information indicating the coverage area of ​​each dynamic cell or cell sector relative to the satellite position of the satellite that generated the cell and the ephemeris data of that satellite, wherein the list of the first plurality of dynamic cells and the indication of the time are included in the indication of the registration area, or

[0212] • An indication of the time interval between the cell ID list and the first plurality of dynamic cells or cell sectors forming the registration area, wherein the cell ID list and the time interval indication are included in the indication of the registration area, or

[0213] • A mapping between geographic regions and tracking regions, and a list of one or more tracking regions forming a registration region, wherein the mapping is read from a storage device, and the list of one or more tracking regions is included in the registration region indication, to determine a second plurality of dynamic cells. The second plurality of dynamic cells are the plurality of cells currently mapped to the registration region. Base station 1740 also includes transceiver 1750, which transmits paging messages for paging UEs in the second plurality of cells.

[0214] For example, base station circuit 1760 includes RA determination circuit 1765.

[0215] Base station 1740 is a scheduling node or scheduling device for a wireless communication system, such as a gNB in ​​3GPP NR, where a non-terrestrial network is implemented. Therefore, dynamic cells are served by satellites (e.g., LEO) or other non-terrestrial platforms (such as airships or hot air balloons). For example, the communication system is an NR-NTN communication system. The communication system may include dynamic cells alone or may include dynamic cells in combination with or supplement to fixed cells, for example, generated by a terrestrial base station. UE 1770 and base station 1740 communicate via a wireless channel. This disclosure is not limited to the specific relationship between the base station and the satellite. Figure 11 and Figure 12 It is possible to have both regenerable and transparent satellites, or to implement a communication system that combines both.

[0216] In addition, the base station communicates with core network entities or systems (such as AMF) via interface 1755.

[0217] In the above description of the base station, "first plurality of cells" refers to dynamic cells, which define the registration area by incorporating information about the time (moment or time interval) at which the first plurality of cells constitute the registration area. On the other hand, "second plurality of cells" are the cells in which the UE will be paged. As will be described further, the second plurality of cells are determined based on the first plurality of cells.

[0218] A base station can serve one or more cells. Furthermore, the registration area can be larger than the number of cells served by base station 1740. Therefore, the "secondary multiple cells" determined by the base station for paging the UE can cover the entire registration area or a sub-area of ​​the registration area.

[0219] Similarly, Figure 17 As shown, an AMF (Access Mobility and Management) system 1710 is disclosed. The AMF system 1710 includes an interface 1720 (“AMF interface”) and a circuit 1730 (AMF circuit). The AMF interface 1720 receives a registration request from a UE, which includes:

[0220] • Indication of the UE's first position, or

[0221] • The cell ID of the last cell the UE has visited and the timestamp indicating the first moment the UE was in the last cell.

[0222] AMF circuit 1730 determines and generates an indication of a registration area including the first location of the UE. The indication of the registration area includes:

[0223] • A list of cell IDs for multiple dynamic cells or cell sectors of dynamic cells, and a second-moment indication of the registration area formed by multiple dynamic cells (wherein the registration area is determined based on coverage area information indicating the coverage area of ​​each of the multiple dynamic cells or cell sectors relative to the satellite position of the satellite that generated the cell and the ephemeris data of that satellite), or

[0224] • An indication of the time interval between the cell ID list and the formation of a registration area by multiple dynamic cells or cell sectors, or

[0225] • Form a list of one or more tracking regions for the registered region, wherein the list of one or more tracking regions is determined based on a mapping between geographic regions and tracking regions, which is read from a storage device.

[0226] AMF interface 1720 sends a registration acceptance message that includes an indication of the registration area.

[0227] The AMF system 1710 is an AMF entity for core networks such as fifth-generation cores. For example, an AMF system can be implemented as a server, within a server hosting other core network entities, or distributed across multiple nodes.

[0228] AMF system 1710 and base station 1740 communicate via interfaces 1720 and 1755. For example, interfaces 1720 and 1755 form an NG interface. AMF system 1710 and base station 1740 can communicate via interfaces 1720 and 1755 over a wired connection (which may include fiber optic cable) or a wireless connection (e.g., in the case of a regenerating satellite). Base station interface 1755 may be included in base transceiver 1750 or may be different from base transceiver 1750.

[0229] For example, such as Figure 17 As shown, the AMF circuit 1730 includes the RA determination circuit 1735.

[0230] As described above, UE 1770 and AMF 1710 exchange registration request messages and registration acceptance messages. This exchange can be performed via base station 1740, which can forward these control messages for the registration process. Base transceiver 1750 can receive registration request messages from the UE and send registration acceptance messages to the UE. Similarly, base station interface 1755 can send registration request messages to the AMF and receive registration acceptance messages from the AMF.

[0231] Corresponding to the aforementioned user equipment, a communication method for a user equipment (UE) is provided. For example... Figure 19 As shown, the method includes step S1910 of sending a registration request, the registration request including at least one of the following:

[0232] • Indication of the UE's first position, or

[0233] • The cell ID of the last cell the UE has visited and the timestamp indicating the first moment the UE was in the last cell.

[0234] The method includes step S1920 of receiving a registration acceptance message including an indication of a registration area, wherein the registration area includes a first location of the UE. Furthermore, the method includes step S1930, based on the following:

[0235] • A list of cell IDs for multiple dynamic cells or cell sectors of dynamic cells, an indication of the second time when multiple dynamic cells form a registration area, coverage area information indicating the coverage area of ​​the cell or cell sector relative to the satellite position of the satellite that generated the cell and ephemeris data for each dynamic cell, and a measurement of the UE's second position, wherein the list of multiple dynamic cells and the indication of the second time are included in the indication of the registration area, or

[0236] • A list of cell IDs, an indication of the time interval between multiple dynamic cells or cell sectors forming a registration area, and the cell ID of a newly accessed cell or cell sector, including the UE's second location and different from the last cell, wherein the list of cell IDs and the indication of the time interval are included in the indication of the registration area, or

[0237] • Measurement of the second location and mapping between the geographic area and the tracking area, and a list of one or more tracking areas forming the registered area, wherein the mapping is read from a storage device, and the list of one or more tracking areas is included in the indication of the registered area.

[0238] To determine whether the UE is in the registration area at the second location.

[0239] Corresponding to the aforementioned base station, a communication method for the base station is also disclosed. Figure 20 The method shown includes step S2010 of receiving a paging request for paging a user equipment (UE), the paging request including an indication of a registration area. The method also includes step S2020, based on the following:

[0240] • A list of cell IDs for the first plurality of dynamic cells or cell sectors of dynamic cells, an indication of the time when the first plurality of dynamic cells form a registration area, and coverage area information indicating the coverage area of ​​the cell or cell sector relative to the satellite position of the satellite that generated the cell and ephemeris data of the satellite for each dynamic cell in the first plurality of dynamic cells, wherein the list of the first plurality of dynamic cells and the indication of the time are included in the indication of the registration area, or

[0241] • An indication of the time interval between the cell ID list and the first plurality of dynamic cells or cell sectors forming the registration area, wherein the cell ID list and the time interval indication are included in the indication of the registration area, or

[0242] The method involves mapping geographic regions to tracking regions and forming a list of one or more tracking regions that constitute a registered region, wherein the mapping is read from a storage device and the list of one or more tracking regions is included in an indication of the registered region, to determine a second plurality of dynamic cells currently mapped to the registered region. The method also includes step S2030 of transmitting a paging message for paging the UE in the second plurality of cells.

[0243] Furthermore, corresponding to the AMF system disclosed above, a communication method for the AMF system is provided. For example... Figure 21 As shown, the method for the AMF system includes step S2110 of receiving a registration request from a user equipment (UE), the registration request including:

[0244] • Indication of the UE's first position, or

[0245] • The cell ID of the last cell the UE has visited and the timestamp indicating the first moment the UE was in the last cell.

[0246] The method for the AMF system includes generating an indication of a registration area that includes the first location of the UE. The indication of the registration area includes:

[0247] • A list of cell IDs for multiple dynamic cells or cell sectors of dynamic cells, and a second-moment indication of the registration area formed by multiple dynamic cells, wherein the registration area is determined based on coverage area information indicating the satellite position of each of the multiple dynamic cells or cell sectors relative to the satellite that generated the cell, and the ephemeris data of that satellite, or

[0248] • An indication of the time interval between the cell ID list and the formation of a registration area by multiple dynamic cells or cell sectors, or

[0249] • Form a list of one or more tracking regions for the registered region, wherein the list of one or more tracking regions is determined based on a mapping between geographic regions and tracking regions, which is read from a storage device.

[0250] In addition, the method used for AMF includes sending a registration acceptance message that includes an indication of the registration area.

[0251] In this disclosure, any interpretations and examples should be interpreted as applicable to each of the UE, base station, and AMF systems, and should also apply to apparatus and methods, unless the context otherwise indicates.

[0252] Mapping of stored TAC and geographic regions

[0253] In some embodiments, the mapping between TACs and geographic areas is predefined as a fixed relationship and is installed in the UE's memory. The memory can be a memory device, a SIM (Subscriber Identity Module), built-in memory, or other memory device. The UE determines its location, for example, using GNSS (Global Navigation Satellite System), derives its TAC based on its location information, and sends the derived TAC as an indication of its location to the AMF. The UE then receives a list of one or more tracking areas (which may be indicated by TACs) from the AMF in a registration acceptance message as an indication of the registered area. When the UE needs to determine whether it is still in the registered area at a certain location ("second location") (e.g., for periodic updates or when camping on or accessing a new cell), UE circuitry 1790 reads the mapping between tracking areas or TACs and geographic areas from the storage device. Therefore, the UE may also include a storage interface for reading mappings from the storage device. The UE determines whether it is in a registered area including the TAC(s) in the list based on the second location (particularly the TACs formed based on the second location, thus indicating the second location), the received list of TAC(s), and the stored mapping.

[0254] For example, in the mapping between TACs and geographic regions, a country can be assigned one TAC (e.g., TAC1 = Germany, TAC2 = Austria, TAC3 = Switzerland, etc.). For larger countries, multiple TACs can be defined, which can be assigned to provinces, states, etc. The boundaries of geographic regions can be stored in the UE or a storage device such as a SIM, or derived from map information (such as a digital map stored in the UE or a storage device). Therefore, based on location measurements, the UE is able to know which region it is located in.

[0255] Implementations using stored mappings between TACs and geographic regions offer backward compatibility because the registered region can be notified to the UE using a TAC or signaled as in the conventional approach. However, as the mapping is stored in the UE or on a storage device such as a SIM, the TA definition (the mapping from a TAC to a region) can be difficult to update.

[0256] The cell coverage area at the time of the event

[0257] In some embodiments, the registration area (or tracking area) is defined by the union of the (dynamic) cell coverage areas at a given moment.

[0258] The cell coverage area can be defined by one of the following pieces of information, which can be included in the coverage area information and are therefore available to the UE for each of the multiple dynamic cells. Figures 22 to 24 The text shows:

[0259] In the first example, such as Figure 22 As shown, the cell area is defined by the satellite beam direction of each beam forming the cell (as shown in the reference). Figure 13 and Figure 14 The cell can be defined by a beam (which may include one or more beams) and the radius or diameter of the beam on Earth (such as the radius or diameter of the cell or the area covered by the beam on Earth). In this case, the cells may overlap.

[0260] In the second example, such as Figure 23 As shown, the cell region of a dynamic cell is defined by polygons that define the coverage area in a non-overlapping manner. For example, the cell region is defined by vertices of non-overlapping shapes such as rectangles or hexagons.

[0261] For example, a reference point (such as an angle or center) can be used to indicate a polygon. This reference point could be a position relative to the current satellite position available from ephemeris data, plus a different indication of the polygon's side length or size. As another example, the polygon can be indicated using the coordinates of all its angles relative to the satellite position.

[0262] exist Figure 24 In the third example shown, the cell can be defined by the cell center and the in-coverage distance from that center (e.g., the in-coverage radius). In this example, the signaling can be similar to that in the first example.

[0263] The coverage area information, as defined above for the first through third options, can be provided relative to the location of a satellite position (e.g., the satellite position relative to the satellite (or multiple satellites) generating the satellite beam, which varies over time and can be derived from ephemeris data for a given point in time). As the satellite moves over time, the coverage area (e.g., its size) may also change over time. For example, the size of the satellite beam area can be adjusted to the UE density or population density of the area covered by the satellite beam. Therefore, when a satellite moves over an area of ​​Earth with a high population density, the coverage area, such as the beam coverage area or ground cell / beam area, may shrink to provide smaller cells to accommodate the increased demand caused by a higher number of UEs requiring service.

[0264] like Figure 25 As shown, the tracking area or registration area is defined by the union of cell areas associated with the timestamp (e.g., TA 1 = {at t = 13:01, cell 1, cell 2, cell 3, cell 4}, and TA 2 = {at t = 13:01, cell 5, cell 6, cell 7, cell 8}).

[0265] If based on Figures 22 to 24In the example above, the cell coverage area of ​​a mobile cell is defined in relation to a given timestamp. The user equipment can then use the cell coverage area information, the timestamp, and satellite ephemeris data to calculate the area on Earth covered by these cells at the indicated time. The registration area and / or tracking area can then be determined as the area covered by multiple cells at a given time. Therefore, the tracking area and / or registration area can be considered as defined by "frozen cells" that cover or will cover the registration area at the indicated time.

[0266] For example, the UE receives coverage area information within the system information. For instance, the cell coverage area is signaled to the UE from the gNB via broadcast RRC signaling, such as SIB. In addition to the cell coverage area, the UE can also receive satellite ephemeris data or partial ephemeris data within the system information, and then the UE can use this data to calculate the satellite's motion relative to the Earth's surface (possibly using other portions of the ephemeris data pre-stored in storage).

[0267] Registration area via NAS signaling (e.g., Figure 6 and Figure 7 The registration acceptance message or configuration update command message shown is signaled from the AMF to the UE. It is sufficient to signal only the TA to which the UE has registered. These TAs can be signaled in particular by signaling "frozen cells" (i.e., a list of cell IDs and the timestamps at which the cells in the list form a registration area). For example, the registration area = {at t=13:01, cell 1, cell 2, cell 3, cell 4, cell 5, cell 6, cell 7, cell 8} corresponds to... Figure 25 TAC 1 and TAC 2 in the code. These cell IDs can be used instead of TA codes, and the UE does not need TA codes to determine the registration area. However, the concept of a tracking area can still be used at the AMF or base station side. For example, the AMF can include multiple cells to form a registration area assigned to the UE.

[0268] Therefore, the UE knows the mapping between the registered area and the geographic location. Based on this, the UE can determine whether it has moved out of the registered area according to its location information (such as GNSS location measurements).

[0269] For example, to determine whether a UE is still within the registered area, the UE can test whether it is within the corresponding cell coverage area for each of the "frozen cells" that constitute the registered area at a given time, for example, by comparing the distance of the UE to the cell center with the cell radius. Once the UE identifies a frozen cell coverage area where the distance to the center is less than the radius, the UE knows it is within the registered area and can stop the calculation. Alternatively, based on multiple cell coverage areas, the UE can calculate the extent or boundaries of the registered area and determine whether the UE is within these boundaries for the entire registered area.

[0270] During the cell planning phase, cell coverage area information can be further pre-configured in both the AMF system and the gNB. Alternatively, the cell coverage area information can be signaled from the gNB to the AMF via ngAP signaling (e.g., ng setup request message or RAN configuration update message). Figure 8 and Figure 9 In addition, the mapping between cells and gNBs can be pre-configured in the AMF. The UE reports the cell ID and timestamp of the last cell it visited, or alternatively, an indication of the UE's location, to the AMF via a registration request message.

[0271] Therefore, the AMF knows which gNB(s) cover the registered area at any given time and is able to determine which gNB(s) deliver the paging message.

[0272] Furthermore, the tracking area and registration area, defined according to the cell ID and timestamp corresponding to the "frozen cell," are signaled from the AMF to the gNB, for example, in the paging message. Therefore, the gNB knows which cell(s) cover the registration area and is able to determine in which cell the paging should be broadcast.

[0273] Figure 26 A possible example of a registration and paging call procedure is shown. As illustrated, the gNB sends an SIB to the UE, which includes cell coverage information, including an indication of the cell coverage area relative to the satellite location. The SIB may also include an indication of satellite ephemeris data, unless the ephemeris data is entirely stored on the UE side. Furthermore, the gNB may send the cell coverage area information included in the NG establishment request message to the AMF (e.g., if the cell coverage area information is not pre-configured in the AMF).

[0274] At the initial registration time t, the UE sends a registration request message to the AMF, which includes the UE's location information or the cell ID and timestamp of the last visited cell. In response, the AMF sends a registration acceptance message to the UE, which includes a list of cell IDs and timestamps indicating the timestamps when the cells in the list form a registration area, serving as an indication of the registration area. Figure 26 As shown, registration requests and registration acceptances can be forwarded by gNB.

[0275] At time t+1, when the UE is in an idle state, the AMF receives the UE's downlink data. The AMF then determines the (multiple) gNBs currently mapped to the registered area and serving the cells currently mapped to the registered area. The AMF sends paging messages (or paging request messages) to these gNBs, which include a list of cells and the timestamps indicating that these cells formed the registered area. Using the list, timestamps, and ephemeris data stored at the gNBs, the gNBs determine which cells they serve are currently included in the registered area and perform paging of the UE on those cells included in the registered area.

[0276] When the UE is in RRC idle mode, paging is initiated by the AMF. Therefore, the AMF sends paging messages to (multiple) base stations, and the base stations broadcast paging messages in cells within the registered area to page the UE. In this disclosure, the term "paging request" or "paging request message" is used for messages from the AMF to base stations that include an indication of the registered area and may include paging messages for paging the UE.

[0277] At time t+2, the UE can detect that its location is outside the registration area based on location measurements. The UE then sends a new registration request including its current location and receives a new list of cell IDs in the registration acceptance message, along with timestamps indicating that these cells form the UE's new registration area. The UE then replaces its previous registration area with the new one.

[0278] If the cell coverage area information in the SIB is combined with ephemeris data, this data can further assist the UE in performing cell selection without needing to measure radio signal strength, which would otherwise occur frequently due to cell movement. Therefore, cell coverage area information can be used by the UE for cell selection and reselection, as well as to determine whether the UE is in the registered area.

[0279] Furthermore, if the cell coverage area is already available via SIB, only a limited amount of signaling overhead (cell ID plus timestamp) is required to indicate the registered area based on the cell coverage area information.

[0280] The community and the corresponding timer

[0281] In some embodiments, when a cell will cover a given geographic location or region on Earth, the registration area or tracking area is defined by listing all cells and their corresponding associated timings (or time intervals). The UE is provided with a list of cell IDs for dynamic cells and an indication of the time interval at which dynamic cells form the registration area, serving as an indication of the registration area.

[0282] In addition, the registration area is included in the registration acceptance message from the AMF; it may include multiple lists of cell IDs of dynamic cells (or cell sectors) and multiple time interval indications, each time interval indication indicating when a dynamic cell (or cell sector) indicated by the cell ID list forms a registration area for each of the multiple lists of cell IDs.

[0283] Therefore, by notifying the UE of the cells that are in the registered area at multiple time intervals, the signaling of the registered area is not required each time the cells constituting the registered area change.

[0284] Figure 27 An example is shown where two tracking regions, TA1 and TA2, change as follows during two time intervals, 13:01–13:10 and 13:11–13:20 (similar to...). Figure 25 The example is merely illustrative, and this disclosure is not limited to any particular length of time interval or the number of cell IDs in a registration area or tracking area:

[0285] ·TA 1={13:01–13:10 Community 1, Community 2, Community 3;

[0286] 13:11–13:20 Community 2, Community 3, Community 4;

[0287] …}

[0288] ·TA 2={13:01–13:10 Community 4, Community 5, Community 6;

[0289] 13:11–13:20 Community 5, Community 6, Community 7;

[0290] …}

[0291] from Figure 27 As can be seen, the set of cells included in the TA remains constant within a time period or time interval (10 minutes in the example above). Therefore, the TA (and correspondingly, the registration area) is obtained because the cells are constantly moving.

[0292] In such embodiments, a list(s) of cell IDs and corresponding time intervals are signaled to the UE as an indication of the registration area, and a tracking area code is not required on the UE side. However, the tracking area can be used on the AMF side to determine the registration area to be assigned to the UE. This disclosure is not limited to the specific method by which the tracking area is determined on the AMF side.

[0293] For example, consider from Figure 27 For example, a UE can be assigned a registration region {TA 1; TA 2}.

[0294] Therefore, the UE can be indicated with registration areas for two subsequent time intervals as follows:

[0295] RA = {13:01–13:10 Community 1, Community 2, Community 3, Community 4, Community 5, Community 6;}

[0296] 13:11–13:20 Community 2, Community 3, Community 4, Community 5, Community 6, Community 7}.

[0297] The UE is notified by the AMF via NAS signaling (e.g., REGISTRATION ACCEPT message or CONFIGURATION UPDATECOMMAND message) according to the registration area of ​​a set of multiple cells (corresponding to a list of multiple cell IDs) and the associated timing (e.g., the corresponding time interval in which one of the cell sets forms the registration area).

[0298] There is no need to inform the UE of the coverage area of ​​each cell. Traditional cell (re)selection based on radio signal strength can be reused. As a result, when the UE performs traditional cell (re)selection based on radio signal strength, the UE can determine whether it has moved out of the registration area based on the cell ID of the newly accessed or camped cell and the timing of the accessed cell, without needing to determine its location.

[0299] Furthermore, cell coverage area information can be pre-configured in the AMF (and possibly gNBs) during the cell planning phase, for example, based on estimates of cell coverage for dynamic cells. Additionally, the mapping between cells and gNBs can be pre-configured in the AMF. Therefore, the AMF knows which gNB(s) cover the registered area at any given time, and thus can determine which gNB(s) to deliver paging messages to.

[0300] In addition, the UE signals the cell ID of the last cell it visited and the timestamp of the UE being in that cell (e.g., the timestamp of the signal strength measurement) to the AMF in the REGISTRATION REQUEST message.

[0301] Furthermore, the registration area (and / or tracking area) is signaled to the gNB according to a set of multiple cells (corresponding to multiple cell ID lists) and an associated timing (e.g., a corresponding time interval when one of the cell sets forms a registration area), for example, in a PAGING message (or in a paging request that includes a paging message). As a result, the gNB knows which cells(s) cover the registration area and is able to determine which cells to broadcast paging to.

[0302] Figure 28An exemplary registration and paging call flow is illustrated. At time t, for example, when performing initial registration of the UE, the UE sends a registration request to the AMF, indicating the last visited cell and a timestamp. The UE then receives a registration acceptance message from the AMF, which includes multiple cell sets in sequence (e.g., multiple lists of cell IDs) and an associated timing as an indication of the registration area, the timing at which a set of cells forms the registration area.

[0303] At time t+1, when the UE is to be paged by the core network, the AMF, which has already received DL data from the UE, determines the (multiple) gNBs currently mapped to the registered area and sends paging messages (or paging request messages including paging messages) to these gNBs. These paging messages include a sequential set of multiple cells serving as the registered area and associated timing. In principle, it is sufficient for the gNB to only receive the ID of the cell served by the corresponding gNB. The gNB determines the cell currently mapped to the registered area and performs the paging of the UE.

[0304] At time t+2, when the UE camps on a new cell outside the registration area, a registration request and a registration acceptance message are exchanged between the UE and the AMF in a manner similar to the initial registration at time t. The registration request includes the cell ID of the newly visited cell, and the registration acceptance message includes a new sequence of multiple cell sets indicating the new registration area.

[0305] When the UE is instructed to register a set of cell IDs for a cell region and the associated timing when they form the registration region, the UE is not required to determine its location, and traditional cell selection based on radio strength can be reused. However, the UE can alternatively send location information in the registration request instead of the cell ID and timestamp of the last visited cell.

[0306] Furthermore, mobile cells do not need to broadcast TACs. Therefore, there are no issues related to TAC broadcasting. These issues may include TAC fluctuations due to "hard handover" or overhead due to soft handover.

[0307] Geographic area and radio signal coverage

[0308] In some embodiments, the TA and / or registration area RA are defined by a cell area or “restricted cell area” (corresponding to a cell sector) and associated timing, wherein the “restricted cell area” is defined by the intersection of a geographic zone and radio signal coverage.

[0309] Geographic regions can be pre-installed on the UE (e.g., stored in the SIM or other memory device) and pre-defined in the network (gNB and core network). These geographic regions can be used to define, for example, the national boundaries of authorized areas.

[0310] For example, a satellite beam can broadcast multiple cell IDs (which can correspond to cells and cell sectors or “restricted cell areas”) associated with different cells that may belong to different countries or authorized regions. In this case, when cell (re)selection is performed using signal strength, the UE can receive the same signal strength from multiple cells or cell sectors because they are generated by the same satellite beam. However, multiple cells or sectors corresponding to a “restricted cell area” can be associated with different authorized regions. For example, the satellite beam moves across the earth along the border of two countries and broadcasts two cell IDs for each country. In this disclosure, a “restricted cell ID” refers to a cell sector of a cell within one of predefined geographical regions, and each “restricted cell ID” can have its own cell ID. The UE then selects the cell with the strongest radio strength allowed (or authorized) for a given location.

[0311] For example, when a UE determines that it is not in a registered area (e.g., by location measurement or by comparing the cell ID of the newly camped or visited cell (or the signal strength from multiple cell IDs) with a list of cell IDs of the previously registered area that defines a given time interval), the UE can perform a signal strength measurement for cell (reselection) selection and receive the same or similar signal strength from multiple cells that are therefore candidates for the newly visited cell.

[0312] Then, the UE can determine the geographic region where the UE is located from the stored or pre-installed geographic regions based on location measurements and the definition of the geographic region (which can be read from the storage device or the ground).

[0313] The UE then selects a candidate from the geographic region where it is located as the newly accessed cell or cell sector. This selection is performed based on the association between the cell ID of each of the multiple candidates and one of the stored geographic regions.

[0314] This association between cell ID and geographic region (e.g., mapping between cell ID and geographic region information) can be signaled to the UE from the gNB for each cell within the system information (e.g., SIB) that the UE has already received.

[0315] In addition, the UE can use an installed or stored geographic region to determine which cells included in the cell ID list or multiple lists of cell IDs are within that geographic region, for example, if the cell ID list indicated by the AMF exceeds a restricted geographic region. The UE circuit 1790 can then determine the registration area to be formed from cells or cell sectors from the cell ID(s) list associated with the geographic region where the UE is located.

[0316] Figure 29 An example of multiple cell sectors or “restricted cell areas” divided between different geographic regions or areas is shown. It can be assumed that a satellite beam transmits multiple (e.g., two or more) cell IDs. For example, beam 1 covers both cell 1 and cell 2. Since both the cells or restricted cell areas are within the same radio coverage, the UE detects similar (e.g., substantially the same) radio signal strengths from the two cells associated with the same radio satellite beam. The UE can select restricted cell area (RCA) 1 or RCA 2 based on location information about whether the UE is located in region A or region B, where RCA 1 = intersection {cell 1, region A}, and RCA 2 = intersection {cell 2, region B}. Different tracking areas or registration areas can be indicated by signaling a list of multiple cell IDs (or RCA IDs or cell sector IDs) and associated timing or time intervals:

[0317] ·TA 1 (or RA 1) = {13:01-13:10RCA 1, RCA 3, RCA 5; 13:11-13:20RCA 3, RCA 5, RCA 7};

[0318] ·TA 2 (or RA 2) = {13:01-13:10RCA 2, RCA 4, RCA 6; 13:11-13:20RCA 4, RCA 6, RCA 8}

[0319] As described above, the geographic region or area definition can be stored or installed in the UE or a memory device. Furthermore, the association between the cell ID (or RCA ID) and the geographic region can be broadcast by the gNB, for example, via the SIB. Similar to the description above of the embodiment titled "Cells and Corresponding Timing," the registration area is signaled to the UE from the AMF via NAS signaling (e.g., a registration acceptance message) according to a sequential set of cells and associated timings.

[0320] As a result, the UE performs cell (re)selection based on both location information and radio signal strength, and can determine whether the UE moves out of the registration area based on the cell ID and timing.

[0321] The aspects of signaling to the AMF system and gNB may resemble the description above in the "Cells and Corresponding Timing" section. During the cell planning phase, cell coverage area information (including mappings to the gNB) can be configured or pre-configured in the AMF (and gNB). The UE signals to the AMF in a registration request message the last visited cell and its timestamp, or location information. Additionally, the gNB is signaled according to a sequential set of cells (a list of cell IDs / RCA IDs) and associated timing TA and / or registration area definitions, for example, in a paging message or paging request message, which also includes a paging message to be sent to the UE.

[0322] As a result, the AMF knows which gNB covers the registered area at any given time and can determine which gNB it must deliver a paging message (or paging request message) to. Furthermore, the gNB knows which cell(s) cover the registered area and therefore can determine in which cell the paging message should be broadcast.

[0323] The registration and paging call process between UE, gNB and AMF is as follows: Figure 30 As shown above, the UE receives an SIB sent from the gNB. The SIB includes a mapping between the cell ID (RCA ID) and area information. Furthermore, although the UE is shown sending location information in the registration request (steps 1 and 6), the UE can also send the cell ID and associated timing. Additionally, at time t+2, the UE camps on a new cell outside the registration area. This new cell is selected or determined based on radio strength and the UE's location (e.g., to determine which region or geographic area the UE is located in). Figure 30 The further process shown is similar to Figure 28 The above description of the process is shown in the figure.

[0324] As described in this section, in addition to received signal strength, additional location information is used to control cell accessibility. When multiple cells or cell sectors are transmitted by the same satellite, this additional use of location information to control cell accessibility can help reduce the number of cells in the registered area and reduce paging overhead.

[0325] As described above, a UE can perform cell (re)selection based on location information (e.g., location measurements such as GNSS) or signal strength measurements, for example, selecting a newly accessed cell within or outside the registered area. For instance, if location information is used to determine whether the UE is still within the registered area, cell selection can also be location-based, which can help reduce the need for signal strength measurements. On the other hand, determining whether a UE is within the registered area via signal strength may be useful for UEs that cannot locate or whose location function is disabled.

[0326] In addition, from Figure 26 , Figure 28 and Figure 30 As can be seen, when the circuit determines that the UE is not in the registration area, it sends a registration request, which includes at least one of the following: an indication of the UE's location, or the cell ID of the newly visited cell and a timestamp indicating the time when the UE is in the newly visited cell (e.g., the signal strength has been measured).

[0327] On the other hand, when the UE is within the registered area and DL data is available to the UE, the UE receives a paging message (e.g., one or both of a paging DCI and a paging message) sent by a gNB within the registered area.

[0328] One or more base stations (e.g., gNBs) that perform paging of the UE are determined by the AMF system. Specifically, in some embodiments, the AMF determines the base station currently mapped to the registration area (which has already indicated the registration area to the UE via registration acceptance) and sends a paging request message to one or more base stations. The paging request message includes:

[0329] • A list of cell IDs for multiple dynamic cells or cell sectors and an indication of the second time step, or

[0330] • An indication of the time interval between the list of cell IDs and the first multiple dynamic cells or cell sectors forming a registration area, or

[0331] • Create a list of tracking areas for the registered areas.

[0332] For example, a paging request message may also include a paging message.

[0333] As can be seen from the embodiments of this disclosure, it is not necessary to broadcast a TA code (TAC) within the cell system information to indicate the registration area to the UE. Therefore, issues regarding the mobility tracking area, such as those related to "hard handover" and "soft handover," can be mitigated or avoided. Specifically, for reference... Figures 22 to 30 The described embodiments may not require TA codes at all.

[0334] also, Figures 22 to 30 Each of the above embodiments shown includes timing information for defining the tracking area and the registration area (e.g., defining a time instance for “freezing” a cell or the time interval for each cell to cover the registration area). With such timing information, cell movement can be known in a predictable manner at the gNB and the core network. Furthermore, in the embodiments described in the section titled “Cell Coverage Area at Time,” ephemeris data is also available at the UE, which can use it to determine the registration area and potentially for cell (re)selection.

[0335] As described above, examples and embodiments of this disclosure have been given using the registration area management of an RRC-enabled idle UE as an example. However, this disclosure can also be applied to RAN Notification Area (RNA) management for inactive UEs. The RAN Notification Area is the basis for RAN-level device tracking. RAN Notification Area updates are managed by RRC RAN Notification Area updates sent from the UE to the gNB. A change in the tracking area implies a change in the RNA, therefore, an RRC RAN Notification Area update is implicitly performed whenever the UE performs a registration update as described above.

[0336] This disclosure can be implemented in software, hardware, or software working in conjunction with hardware. Each functional block used in the description of each of the above embodiments can be implemented in part or in whole by an LSI such as an integrated circuit (IC), and each process described in each embodiment can be controlled in part or in whole by the same LSI or a combination of LSIs. An LSI can be formed as a chip on its own, or a chip can be formed to include part or all of the functional blocks. An LSI can include data inputs and outputs coupled thereto. Depending on the level of integration, the LSI herein can be referred to as an IC, a system LSI, a super LSI, or a very large LSI. However, the technology for implementing integrated circuits is not limited to LSIs, but can be implemented using dedicated circuitry, general-purpose processors, or special-purpose processors. Furthermore, an FPGA (Field-Programmable Gate Array) that can be programmed after the LSI is manufactured, or a reconfigurable processor in which the connections and settings of circuit cells disposed within the LSI can be reconfigured, can be used. This disclosure can be implemented as digital processing or analog processing. If future integrated circuit technologies replace large-scale integrated circuits due to advancements in semiconductor technology or other derivative technologies, future integrated circuit technologies can be used to integrate functional blocks. Biotechnology is also applicable.

[0337] This disclosure can be implemented by any kind of device, apparatus or system with communication capabilities (referred to as a communication device).

[0338] The communication device may include a transceiver and processing / control circuitry. The transceiver may include and / or act as a receiver and transmitter. As a transmitter and receiver, the transceiver may include an RF (radio frequency) module, which includes an amplifier, an RF modulator / demodulator, etc., and one or more antennas.

[0339] Some non-limiting examples of such communication devices include telephones (e.g., cellular phones, smartphones), tablets, personal computers (PCs) (e.g., laptops, desktops, netbooks), cameras (e.g., digital still / video cameras), digital players (digital audio / video players), wearable devices (e.g., wearable cameras, smartwatches, tracking devices), game consoles, digital book readers, remote healthcare / telemedicine (remote healthcare and medical) devices, and vehicles that provide communication capabilities (e.g., cars, airplanes, ships), as well as various combinations thereof.

[0340] Communication devices are not limited to portable or mobile devices, but may also include any kind of non-portable or fixed device, equipment or system, such as smart home devices (e.g., appliances, lighting, smart meters, control panels), vending machines and any other “thing” in an “Internet of Things (IoT)” network.

[0341] Communication may include the exchange of data through, for example, cellular systems, wireless LAN systems, satellite systems, and various combinations thereof.

[0342] The communication device may include devices such as controllers or sensors coupled to a communication device that performs the communication functions described in this disclosure. For example, the communication device may include a controller or sensor that generates control signals or data signals used by the communication device performing the communication functions of the communication device.

[0343] Communication devices may also include infrastructure such as base stations, access points, and any other devices, equipment, or systems that communicate with or control such devices as those in the non-limiting examples above.

[0344] In summary, the first embodiment provides a user equipment (UE) including: a transceiver for transmitting a registration request including at least one of the following:

[0345] • Indication of the UE's first position, or

[0346] • The cell ID of the last cell the UE has visited and the timestamp indicating the first moment the UE was in that last cell, and

[0347] Receive a registration acceptance message including an indication of the registration area, which includes the UE's first location and circuitry, based on the following:

[0348] • A list of cell IDs for multiple dynamic cells or cell sectors of dynamic cells, an indication of the second time when multiple dynamic cells form a registration area, coverage area information indicating the satellite position of the cell or cell sector relative to the satellite that generated the cell and the ephemeris data of that satellite for each dynamic cell, and a measurement of the UE's second position, wherein the list of multiple dynamic cells and the indication of the second time are included in the indication of the registration area, or

[0349] • A list of cell IDs, an indication of the time interval between multiple dynamic cells or cell sectors forming a registration area, and the cell ID of a newly accessed cell or cell sector, including the UE's second location and different from the last cell, wherein the list of cell IDs and the indication of the time interval are included in the indication of the registration area, or

[0350] • Measurement of the second location and mapping between the geographic area and the tracking area, and a list of one or more tracking areas forming the registered area, wherein the mapping is read from a storage device, and the list of one or more tracking areas is included in the indication of the registered area.

[0351] To determine whether the UE is located in the registration area at the second position.

[0352] In the second embodiment, in addition to the first embodiment, the transceiver receives coverage area information in the system information.

[0353] In the third embodiment, in addition to the first or second embodiment, the coverage area information includes, for each of the plurality of dynamic cells, the coverage area information includes:

[0354] • The satellite beam direction and the radius or diameter of the coverage area for each beam forming the cell, or

[0355] • Define the coverage area as a polygon in a non-overlapping manner, or

[0356] • The center and radius of the coverage area.

[0357] In the fourth embodiment, in addition to the first embodiment, the indication of the registration area includes a plurality of cell ID lists of dynamic cells or cell sectors of dynamic cells, including the cell ID lists, and a plurality of time interval indications including the time intervals for forming the registration area by the dynamic cells or cell sectors indicated by the cell ID lists for each of the plurality of cell ID lists.

[0358] In the fifth embodiment, in addition to the first or fourth embodiments, when the circuit determines that the UE is not located in the registered area at the second location, and the received signal strengths of multiple candidates for the newly accessed cell or cell sector are substantially the same, the circuit determines the geographical area where the UE is located from the geographical area based on the measurement of the second location and the definition of the geographical area read from the storage device, and selects the candidate included in the geographical area where the UE is located as the newly accessed cell or cell sector based on the association between the cell ID of each candidate among the multiple candidates included in the system information and one of the geographical areas.

[0359] In the sixth embodiment, except for any one of the first to fifth embodiments, the circuit selects the newly accessed cell based on the second location.

[0360] In the seventh embodiment, in addition to the first, fourth, or fifth embodiments, the circuit selects the newly accessed cell based on signal strength measurements.

[0361] In the eighth embodiment, except for any one of the first to seventh embodiments, the transceiver receives paging messages within the registration area.

[0362] In the ninth embodiment, except for any one of the first to eighth embodiments, if the circuit determines that the UE is not in the registration area at the second location, the transceiver sends a second registration request, which includes at least one of the following:

[0363] • Indication of the UE's second position, or

[0364] • The cell ID of the newly visited cell and a timestamp indicating that the UE is already in the newly visited cell at the third moment.

[0365] In a tenth embodiment, a base station is provided, comprising: an interface for receiving a paging request message for paging a user equipment (UE), the paging request message including an indication of a registration area, and a circuit based on the following:

[0366] • A list of cell IDs for the first plurality of dynamic cells or cell sectors of dynamic cells, an indication of the time when the first plurality of dynamic cells form a registration area, and coverage area information indicating the coverage area of ​​the cell or cell sector relative to the satellite position of the satellite that generated the cell and ephemeris data of the satellite for each dynamic cell in the first plurality of dynamic cells, wherein the list of the first plurality of dynamic cells and the indication of the time are included in the indication of the registration area, or

[0367] • An indication of the time interval between the cell ID list and the first plurality of dynamic cells or cell sectors forming the registration area, wherein the cell ID list and the time interval indication are included in the indication of the registration area, or

[0368] • A mapping between geographic regions and tracking regions, and a list of one or more tracking regions forming a registration region, wherein the mapping is read from a storage device, and the list of one or more tracking regions is included in an indication of the registration region, to determine a second plurality of dynamic cells currently mapped to the registration region; and a transceiver, which transmits paging messages for paging the UE in the second plurality of cells.

[0369] In the eleventh embodiment, an Access and Mobility Management Function (AMF) system is provided, including: an interface for receiving a registration request from a User Equipment (UE), comprising:

[0370] • Indication of the UE's first position, or

[0371] • The cell ID of the last cell the UE has visited and the timestamp indicating the first moment the UE was in that last cell, and

[0372] The circuit generates an indication of a registration area including the first location of the UE, the indication of the registration area including:

[0373] • A list of cell IDs for multiple dynamic cells or cell sectors of dynamic cells, and a second-moment indication of the registration area formed by multiple dynamic cells, wherein the registration area is determined based on coverage area information indicating the coverage area of ​​each of the multiple dynamic cells or cell sectors relative to the satellite position of the satellite that generated the cell, and the ephemeris data of the satellite, or

[0374] • An indication of the time interval between the cell ID list and the formation of a registration area by multiple dynamic cells or cell sectors, or

[0375] • Form a list of one or more tracking regions for the registered region, wherein the list of one or more tracking regions is determined based on a mapping between geographic regions and tracking regions, which is read from a storage device.

[0376] The interface sends a registration acceptance message that includes an indication of the registration area.

[0377] In the twelfth embodiment, in addition to the eleventh embodiment, the circuitry determines one or more base stations currently mapped to the registered area, and the interface sends a paging request message to the one or more base stations, the paging request message including:

[0378] • A list of cell IDs for multiple dynamic cells or cell sectors and an indication of the second time step, or

[0379] • An indication of the time interval between the list of cell IDs and the first multiple dynamic cells or cell sectors forming a registration area, or

[0380] • Create a list of tracking areas for the registered areas.

[0381] In the thirteenth embodiment, a communication method for a user equipment (UE) is provided, including sending a registration request, the registration request including at least one of the following:

[0382] • Indication of the UE's first position, or

[0383] • The cell ID of the last cell the UE has visited and the timestamp indicating the first moment the UE was already in that last cell; and the determination of whether the UE is in the registration area at the second location based on the following:

[0384] • A list of cell IDs for multiple dynamic cells or cell sectors of dynamic cells; an indication of the second time when multiple dynamic cells form a registration area; coverage area information for the coverage area of ​​the cell or cell sector relative to the satellite position of the satellite that generated the cell, and ephemeris data of the satellite, for each dynamic cell among the multiple dynamic cells; and a measurement of the second position of the UE, wherein the list of multiple dynamic cells and the indication of the second time are included in the indication of the registration area, or

[0385] • A list of cell IDs, an indication of the time interval between multiple dynamic cells or cell sectors forming a registration area, and the cell ID of a newly accessed cell or cell sector, including the UE's second location and different from the last cell, wherein the list of cell IDs and the indication of the time interval are included in the indication of the registration area, or

[0386] • Measurement of the second location and mapping between the geographic area and the tracking area, and a list of one or more tracking areas forming the registered area, wherein the mapping is read from a storage device, and the list of one or more tracking areas is included in the indication of the registered area.

[0387] In the fourteenth embodiment, a communication method for a base station is provided, including receiving a paging request message from a user equipment (UE), the paging request message including an indication of a registration area; based on the following:

[0388] • A list of cell IDs for the first plurality of dynamic cells or cell sectors of dynamic cells, an indication of the time when the first plurality of dynamic cells form a registration area, and coverage area information indicating the coverage area of ​​each dynamic cell or cell sector relative to the satellite position of the satellite that generated the cell and the ephemeris data of that satellite, wherein the list of the first plurality of dynamic cells and the indication of the time are included in the indication of the registration area, or

[0389] • An indication of the time interval between the cell ID list and the first plurality of dynamic cells or cell sectors forming the registration area, wherein the cell ID list and the time interval indication are included in the indication of the registration area, or

[0390] • A mapping between geographic regions and tracking regions, and a list of one or more tracking regions forming a registration region, wherein the mapping is read from a storage device, and the list of one or more tracking regions is included in an indication of the registration region, to determine a second plurality of dynamic cells currently mapped to the registration region; and to send a paging message for paging the UE in the second plurality of cells.

[0391] In the fifteenth embodiment, a communication method for accessing a Mobility Function (AMF) system is provided, including receiving a registration request from a User Equipment (UE), comprising:

[0392] • Indication of the UE's first position, or

[0393] • The cell ID of the last cell the UE has visited and the timestamp indicating the first moment the UE was in the last cell;

[0394] Generate an indication of a registration area including the UE's first location, the indication of which includes:

[0395] • A list of cell IDs for multiple dynamic cells or cell sectors of dynamic cells, and a second-moment indication of the registration area formed by multiple dynamic cells, wherein the registration area is determined based on coverage area information indicating the satellite position of each of the multiple dynamic cells or cell sectors relative to the satellite that generated the cell, and the ephemeris data of that satellite, or

[0396] • An indication of the time interval between the cell ID list and the formation of a registration area by multiple dynamic cells or cell sectors, or

[0397] • Form a list of one or more tracking regions for the registered region, wherein the list of one or more tracking regions is determined based on a mapping between geographic regions and tracking regions, which is read from a storage device; and

[0398] Send a registration acceptance message that includes an indication of the registration area.

[0399] Note that the second to ninth embodiments are correspondingly applicable to the base station of the tenth embodiment and the AMF system of the eleventh embodiment, and the twelfth embodiment is correspondingly applicable to the base station of the tenth embodiment. Furthermore, the steps performed by the circuit, the steps performed by the transceiver, and the steps performed by the interface mentioned in the above UE, base station, and AMF embodiments correspond to the respective methods.

[0400] In addition, a non-transitory medium is provided for storing program instructions that, when executed on a processing circuit such as a general-purpose processor, cause the processing circuit to perform all the steps of the method embodiments described above.

[0401] An integrated circuit is also provided for a communication device such as a UE, base station, or AMF system, which controls the communication device to perform all the steps of the above method embodiments.

[0402] In summary, user equipment (UE), base stations, AMF (Access and Mobility Management) systems, and corresponding methods are provided. The UE determines whether it is located in a registered area indicated to it by the AMF, and whether the UE is paged by the base station in that registered area, based on signal strength measurements or location, combined with either a dynamic cell ID list or a timed or stored mapping between geographic areas and tracking areas.

Claims

1. A user equipment, UE, comprising: a transceiver, transmitting a registration request, the registration request comprising: • an indication of a first location of the UE, or • a cell ID of a last cell visited by the UE and a timestamp indicating a first time instant at which the UE has been located within the last cell, and receiving a registration accept message comprising an indication of a registration area, and circuitry determining whether the UE is located in the registration area at a second location based on: • a list of cell IDs of a plurality of dynamic cells or cell sectors of dynamic cells, an indication of a second time instant at which the plurality of dynamic cells forms the registration area, coverage area information indicating for each dynamic cell of the plurality of dynamic cells a coverage area of the cell or cell sector relative to a satellite position of a satellite generating the cell and ephemeris data of the satellite, and a measurement of a second location of the UE, wherein the list of the plurality of dynamic cells and the indication of the second time instant are comprised in the indication of the registration area, or • the list of cell IDs, an indication of a time interval at which the plurality of dynamic cells or cell sectors forms the registration area, and a cell ID of a newly visited cell or cell sector comprising the second location of the UE and being different from the last cell, wherein the list of cell IDs and the indication of the time interval are comprised in the indication of the registration area, 2. The UE according to claim 1, wherein the transceiver receives the coverage area information within system information.

3. The UE according to claim 1 or 2, wherein the coverage area information comprises for each dynamic cell of the plurality of dynamic cells: v a satellite beam direction of each beam forming the cell and a radius or diameter of the coverage area, or • a polygon defining the coverage area in a non-overlapping manner, or v a center and a radius of the coverage area.

4. The UE according to claim 1, wherein the registration accept message comprises: a plurality of lists of cell IDs of dynamic cells or cell sectors of dynamic cells, including the list of cell IDs, and a plurality of time interval indications including the time interval, the time interval indications indicating for each of the plurality of lists of cell IDs a time interval at which the dynamic cells or cell sectors indicated by the list of cell IDs respectively forms the registration area.

5. The UE according to claim 1 or 4, wherein when the circuitry determines that the UE is not located in the registration area at the second location and a plurality of candidates of the newly visited cell or cell sector have substantially the same received signal strength, the circuitry: determines a geographical area in which the UE is located from a definition of geographical areas based on the measurement of the second location and read from a storage, and selects a candidate comprised in the geographical area in which the UE is located as the newly visited cell or cell sector based on an association between a cell ID of each of the plurality of candidates comprised in system information and one of the geographical areas. ​ 6. The UE of claim 1 or 4, wherein the circuitry selects the newly visited cell based on the second location.

7. The UE of claim 1 or 4, wherein the circuitry selects the newly visited cell based on signal strength measurements.

8. The UE of claim 1 or 4, wherein the transceiver receives a paging message within the registration area.

9. The UE of claim 1 or 4, wherein if the circuitry determines that the UE is not located in the registration area at the second location, the transceiver sends a second registration request, the second registration request including at least one of: v an indication of the second location of the UE, or • a cell ID of the newly visited cell and a timestamp indicating a third time instant at which the UE has been located within the newly visited cell.

10. A base station comprising: an interface that receives a paging request message for paging a user equipment, UE, the paging request message including an indication of a registration area, circuitry that determines a second plurality of dynamic cells currently mapped to the registration area based on: • a list of cell IDs of a first plurality of dynamic cells or cell sectors of dynamic cells, an indication of a time instant at which the first plurality of dynamic cells forms the registration area, and for each dynamic cell of the first plurality of dynamic cells, coverage area information indicating a coverage area of the cell or cell sector relative to a satellite position of a satellite generating the cell and ephemeris data of the satellite, wherein the list of cell IDs of the first plurality of dynamic cells and the indication of the time instant are included in the indication of the registration area, or • the list of cell IDs and an indication of a time interval at which the plurality of dynamic cells or cell sectors forms the registration area, wherein the list of cell IDs and the indication of the time interval are included in the indication of the registration area, a transceiver that sends a paging message for paging the UE in the second plurality of cells.

11. An access and mobility management function, AMF, system comprising: an interface that receives a registration request of a user equipment, UE, including: • an indication of a first location of the UE, or • a cell ID of a last cell visited by the UE and a timestamp indicating a first time instant at which the UE has been located within the last cell; and circuitry that generates an indication of a registration area including the first location of the UE, the indication of the registration area including: • a list of cell IDs of a plurality of dynamic cells or cell sectors of dynamic cells, an indication of a second time instant at which the plurality of dynamic cells forms the registration area, wherein the registration area is determined based on, for each of the plurality of dynamic cells or cell sectors, coverage area information indicating a coverage area of the cell or cell sector relative to a satellite position of a satellite generating the cell and ephemeris data of the satellite, or • the list of cell IDs and an indication of a time interval at which the plurality of dynamic cells or cell sectors forms the registration area, wherein the interface sends a registration accept message including the indication of the registration area.

12. A communication method for a user equipment, UE, comprising: ​ sending a registration request, the registration request comprising the following: • an indication of a first location of the UE, or v a cell ID of a last cell visited by the UE and a timestamp indicating a first time instant at which the UE has been located within the last cell; receiving a registration accept message comprising an indication of a registration area; and determining whether the UE is located in the registration area in a second location based on the following: • a list of cell IDs of a plurality of dynamic cells or cell sectors of dynamic cells, an indication of a second time instant at which the plurality of dynamic cells forms the registration area, coverage area information indicating a coverage area of the cell or cell sector relative to a satellite position of a satellite generating the cell for each dynamic cell of the plurality of dynamic cells and ephemeris data of the satellite, and a measurement of a second location of the UE, wherein the list of the plurality of dynamic cells and the indication of the second time instant are comprised in the indication of the registration area, or • the list of cell IDs, an indication of a time interval at which the plurality of dynamic cells or cell sectors forms the registration area, and a cell ID of a new visited cell or cell sector comprising the second location of the UE and being different from the last cell, wherein the list of cell IDs and the indication of the time interval are comprised in the indication of the registration area, 13. A communication method for a base station, comprising: receiving a paging request message for paging a user equipment, UE, the paging request message comprising an indication of a registration area; determining a second plurality of dynamic cells currently mapped to the registration area based on the following: • a list of cell IDs of a first plurality of dynamic cells or cell sectors of dynamic cells, an indication of a time instant at which the first plurality of dynamic cells forms the registration area, and coverage area information indicating a coverage area of the cell or cell sector relative to a satellite position of a satellite generating the cell for each dynamic cell of the first plurality of dynamic cells and ephemeris data of the satellite, wherein the list of the first plurality of dynamic cells and the indication of the time instant are comprised in the indication of the registration area, or • the list of cell IDs and an indication of a time interval at which the first plurality of dynamic cells or cell sectors forms the registration area, wherein the list of cell IDs and the indication of the time interval are comprised in the indication of the registration area, and sending a paging message for paging the UE in the second plurality of cells.

14. A communication method for an Access Mobility Function, AMF, system, comprising: receiving a registration request of a user equipment, UE, the registration request comprising: • an indication of a first location of the UE, or • a cell ID of a last cell visited by the UE and a timestamp indicating a first time instant at which the UE has been located within the last cell, generating an indication of a registration area comprising the first location of the UE, the indication of the registration area comprising: • a list of cell IDs of a plurality of dynamic cells or cell sectors of dynamic cells, an indication of a second time instant at which the plurality of dynamic cells forms the registration area, coverage area information indicating a coverage area of the cell or cell sector relative to a satellite position of a satellite generating the cell for each dynamic cell of the plurality of dynamic cells and ephemeris data of the satellite, and a measurement of a second location of the UE, wherein the list of the plurality of dynamic cells and the indication of the second time instant are comprised in the indication of the registration area, or • the list of cell IDs and an indication of a time interval at which the plurality of dynamic cells or cell sectors forms the registration area, and a cell ID of a new visited cell or cell sector comprising the second location of the UE and being different from the last cell, wherein the list of cell IDs and the indication of the time interval are comprised in the indication of the registration area, • a list of cell IDs of a plurality of dynamic cells or cell sectors of dynamic cells, an indication of a second time instant at which the plurality of dynamic cells form the registration area, wherein the registration area is determined based on coverage area information indicating, for each of the plurality of dynamic cells or cell sectors, a coverage area of the cell or cell sector relative to a satellite position of a satellite generating the cell and ephemeris data of the satellite, or • the list of cell IDs and an indication of a time interval at which the plurality of dynamic cells or cell sectors form the registration area; and sending a registration accept message comprising an indication of the registration area. In some embodiments, the registration accept message comprises an indication of a list of cell IDs of a plurality of dynamic cells or cell sectors of dynamic cells, an indication of a second time instant at which the plurality of dynamic cells form the registration area, wherein the registration area is determined based on coverage area information indicating, for each of the plurality of dynamic cells or cell sectors, a coverage area of the cell or cell sector relative to a satellite position of a satellite generating the cell and ephemeris data of the satellite, or the list of cell IDs and an indication of a time interval at which the plurality of dynamic cells or cell sectors form the registration area.

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