Apparatus and method for determining whether a user's device is located within a registration area.

Abstract

To provide a method and apparatus for facilitating efficient paging for NTN (non-terrestrial network) communication systems with earth moving cells.SOLUTION: A communication system includes a gNB which is a transceiver for receiving a registration request and transmitting a registration accept message including a list of one or more tracking areas forming a registration area, the registration request including an indication of a first location of user equipment (UE), the list of one or more tracking areas including the indication of the first location of the UE. The gNB comprises a circuit for generating the registration accept message including the list of one or more tracking areas. The tracking areas correspond to cell IDs of a plurality of earth moving cells associated with time intervals forming the registration area.SELECTED DRAWING: Figure 26

Description

Technical Field

[0001] The present disclosure relates to the transmission and reception of signals in a communication system. More particularly, the present disclosure relates to methods and apparatuses for such transmission and reception.

Background Art

[0002] The 3rd Generation Partnership Project (3GPP (registered trademark): 3rd Generation Partnership Project) is working on the technical specifications of next-generation cellular technology, also known as the fifth generation (5G: fifth generation), including the "New Radio" (NR: New Radio) radio access technology (RAT: radio access technology) that operates in a frequency range up to 100 GHz. NR is a successor to technologies represented by Long Term Evolution (LTE) and LTE-Advanced (LTE-A: LTE Advanced).

[0003] In systems such as LTE, LTE-A, and NR, further improvements and options can facilitate the efficient operation of communication systems and specific devices related to such systems.

Prior Art Documents

Non-Patent Documents

[0004]

Non-Patent Document 1

Non-Patent Document 2

Non-Patent Document 3

Non-Patent Document 4

Non-Patent Document 5

Non-Patent Document 6

[0005] One non-limiting and exemplary embodiment facilitates efficient paging for an NTN communication system having an earth moving cell.

[0006] One of the main aspects of the present invention is a base station, A transceiver that receives a registration request and transmits a registration acceptance message including a list of one or more tracking areas forming a registration area, wherein the registration request includes notification of a first location of a user equipment (UE), and the list of one or more tracking areas includes notification of the first location of the UE, A circuit for generating the registration acceptance message, which includes a list of one or more tracking areas, wherein the tracking areas correspond to the cell IDs of a plurality of Earth movement cells associated with time intervals forming the registration areas. It is a base station equipped with [the necessary features].

[0007] In one embodiment, the technology disclosed herein is user equipment (UE), During operation, A registration request is sent, and the said registration request is, • Notification of the first position of the aforementioned UE, or • The cell ID of the last cell visited by the UE, and a timestamp indicating the first time (time instant) when the UE was located within that last cell. It includes at least one of the following: A registration acceptance message is received that includes a notification of the registration area, and the registration area includes the first location of the UE, Transmitter and receiver, During operation, Based on a list of cell IDs of multiple Earth-moving cells or cell sections of said Earth-moving cells, a notification of a second time when said multiple Earth-moving cells form said registration area, coverage area information and ephemeris data of said satellite indicating the coverage area of ​​said cell or cell section relative to the satellite position of the satellite that generates said cell, and a measurement of the second position of said UE, where said list of said multiple Earth-moving cells and the notification of the second time are included in said notification of said registration area, Based on the list of cell IDs, the notification of the time intervals in which the plurality of Earth-moving cells or cell sections form the registration area, and the cell ID of a newly visited cell or cell section, which includes the second location of the UE and is different from the last cell, where the list of cell IDs and the notification of the time intervals are included in the notification of the registration area, or · Based on the measurement value at the second position, the mapping between the geographical area and the tracking area, and the list of one or more tracking areas forming the registration area, where the mapping is read from storage and the list of one or more tracking areas is included in the notification of the registration area, a circuit for determining whether the UE is located within the registration area at the second position, characterized by a user equipment comprising.

[0008] Note that general or specific embodiments may be implemented as a system, method, integrated circuit, computer program, storage medium, or any optional combination thereof.

[0009] Further benefits and advantages of the disclosed embodiments will become apparent from the specification and the drawings. Benefits and / or advantages may be obtained individually by various embodiments and features of the specification and the drawings, and not all of them are necessarily provided to obtain one or more of such benefits and / or advantages.

[0010] Hereinafter, exemplary embodiments will be described in more detail with reference to the accompanying figures and drawings.

Brief Description of the Drawings

[0011] [Figure 1] It is a diagram showing an exemplary architecture of a 3GPP NR system. [Figure 2] It is a schematic diagram showing the functional split between NG-RAN and 5GC. [Figure 3] It is a sequence diagram of an RRC connection setup / reconfiguration procedure. [Figure 4]It is a schematic diagram showing the usage scenarios of enhanced mobile broadband (eMBB), massive machine type communications (mMTC), and ultra reliable and low latency communications (URLLC). [Figure 5] It is a block diagram showing an exemplary 5G system architecture for a non-roaming scenario. [Figure 6] It is a diagram showing the registration procedure. [Figure 7] It is a diagram showing the UE configuration update procedure. [Figure 8] It is a diagram showing the NG setup procedure. [Figure 9] It is a diagram showing the RAN configuration update procedure. [Figure 10] It is a schematic diagram showing the relationship between the registration area, tracking area, and cell. [Figure 11] It is a diagram showing the scenario of a non-terrestrial network (NTN) where transmission between a terminal and a remote radio unit including a satellite and an NTN gateway is performed. [Figure 12] It is a diagram showing the scenario of a non-terrestrial network where transmission between a terminal and a satellite including a gNB as a scheduling device is performed. [Figure 13] It is a diagram showing the mapping of a single cell (PCI) to multiple satellite beams. [Figure 14] It is a diagram showing the mapping of a single cell (PCI) to a single satellite beam. [Figure 15] It is a diagram showing the terrestrial mobile cell scenario in NTN. [Figure 16] It is a diagram showing the ephemeris parameters. [Figure 17] It is a block diagram showing an AMF system, a base station, and a user equipment (UE). [Figure 18]This is a block diagram showing the RA location determination circuitry of a user device. [Figure 19] This is a flowchart of the communication method for user devices. [Figure 20] This is a flowchart of communication methods for base stations. [Figure 21] This is a flowchart of the communication method for AMF. [Figure 22] This figure shows the cell coverage area based on the direction and diameter of the satellite beam. [Figure 23] This diagram shows a notification of cell coverage areas based on non-overlapping shapes. [Figure 24] This figure shows the cell coverage area notification based on the cell center and in-coverage distance. [Figure 25] This diagram shows the definition of a tracking area as a union of cell areas at a given time. [Figure 26] This diagram shows the registration and paging call flow. [Figure 27] This figure shows a notification of the tracking area using a list of cells associated with time intervals. [Figure 28] This diagram shows the registration and paging call flow. [Figure 29] This diagram shows the definition of the registration area using a restricted cell area. [Figure 30] This diagram shows the registration and paging call flow. [Modes for carrying out the invention]

[0012] 5G NR system architecture and protocol stack

[0013] 3GPP is working on the next release of fifth-generation cellular technology, simply called 5G, which includes the development of a new radio access technology (NR) that operates at frequencies up to 100 GHz. The first version of the 5G standard was completed at the end of 2017, which will enable testing and commercial deployment of smartphones compliant with the 5G NR standard.

[0014] In particular, the overall system architecture envisions an NG-RAN (Next Generation Radio Access Network) including gNBs (gNodeBs) that provide NG Radio Access User Plane (SDAP / PDCP / RLC / MAC / PHY) and Control Plane (RRC, Radio Resource Control) protocol terminations to the UE. The gNBs are interconnected by Xn interfaces. The gNBs are also connected to the NGC (Next Generation Core) by Next Generation (NG) interfaces, more specifically to the Access and Mobility Management Function (AMF) (e.g., a specific core entity that performs the AMF) by NG-C interfaces, and to the User Plane Function (UPF) (e.g., a specific core entity that performs the UPF) by NG-U interfaces. The NG-RAN architecture is shown in Figure 1 (see, for example, Section 4 of Non-Patent Document 1).

[0015] The NR user plane protocol stack (see, for example, section 4.4.1 of Non-Patent Document 1) includes the PDCP (Paper Data Convergence Protocol, see section 6.4 of Non-Patent Document 1), RLC (Radio Link Control, see section 6.3 of Non-Patent Document 1), and MAC (Medium Access Control, see section 6.2 of Non-Patent Document 1) sublayers, which are terminated at the network-side gNB. In addition, a new access layer (AS) sublayer (SDAP, Service Data Adaptation Protocol) is introduced on top of PDCP (see, for example, subclose 6.5 of Non-Patent Document 1). A control plane protocol stack is also defined for NR (see, for example, section 4.4.2 of Non-Patent Document 1). An overview of the Layer 2 functionality is given in subclose 6 of Non-Patent Document 1. The functions of the PDCP, RLC, and MAC sublayers are listed in sections 6.4, 6.3, and 6.2 of Non-Patent Document 1, respectively. The functions of the RRC layer are listed in subclosed section 7 of Non-Patent Document 1.

[0016] For example, the media access control layer handles scheduling and scheduling-related functions, including logical channel multiplexing and handling of various numerologies.

[0017] The Physical Layer (PHY) is responsible for, for example, encoding, PHY HARQ processing, modulation, multi-antenna processing, and mapping signals to appropriate physical time-frequency resources. It also handles the mapping of transport channels to physical channels. The Physical Layer provides services to the MAC layer in the form of transport channels. A physical channel corresponds to a set of time-frequency resources used for transmitting a particular transport channel, and each transport channel is mapped to a corresponding physical channel. For example, physical channels include PRACH (Physical Random Access Channel), PUSCH (Physical Uplink Shared Channel), and PUCCH (Physical Uplink Control Channel) for uplinks, and PDSCH (Physical Downlink Shared Channel), PDCCH (Physical Downlink Control Channel), and PBCH (Physical Broadcast Channel) for downlinks.

[0018] Use cases / deployment scenarios for NR may include enhanced mobile broadband (eMBB), ultra-high reliability, low latency communication (URLLC), and massive machine-type communication (mMTC), which have diverse requirements in terms of data speed, latency, and coverage. For example, eMBB is expected to support peak data speeds (20 Gbps for downlink and 10 Gbps for uplink) and data speeds experienced by users that are about three times the data speed provided by IMT-Advanced. URLLC, on the other hand, requires ultra-low latency (0.5 ms user plane latency for UL and DL respectively) and high reliability (1-10 ms within 1 ms). -5Stricter requirements are imposed regarding ). Finally, mMTCs preferably have a high connectivity density (1,000,000 devices / km in urban environments). 2 ), it may require wide coverage in harsh environments and extremely long-lasting batteries (15 years) for low-cost devices.

[0019] Therefore, OFDM neurology suitable for one use case (e.g., subcarrier interval, OFDM symbol duration, cyclic prefix (CP) duration, number of symbols per scheduling interval) may not work well for other use cases. For example, low-latency services may preferably require shorter symbol durations (and thus larger subcarrier intervals) and / or fewer symbols per scheduling interval (aka TTI) than mMTC services. Furthermore, deployment scenarios with large channel delay spreads may preferably require longer CP durations than scenarios with smaller delay spreads. Subcarrier intervals need to be optimized accordingly to maintain similar CP overhead. NR may support subcarrier intervals of two or more values. Accordingly, subcarrier intervals of 15kHz, 30kHz, 60kHz, ... are currently being considered. Symbol duration T u The subcarrier spacing Δf is given by the equation Δf = 1 / T u This is directly related. As in the case of LTE systems, the term "resource element" may be used to represent the smallest resource unit consisting of one subcarrier over the length of one OFDM / SC-FDMA symbol.

[0020] In the new 5G-NR wireless system, resource grids for subcarriers and OFDM symbols are defined for each neurology and carrier, for both uplink and downlink. Each element within 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 Non-Patent Literature 2).

[0021] 5G NR function splitting between NG-RAN and 5GC

[0022] Figure 2 shows the functional partitioning between NG-RAN and 5GC. The logical nodes of NG-RAN are gNB or ng-eNB (next-generation eNB). 5GC has logical nodes AMF, UPF, and SMF.

[0023] Specifically, gNB and ng-eNB host the following main functions: - Features for wireless resource management, such as wireless bearer control, wireless admission control, connectivity mobility control, and dynamic resource allocation (scheduling) to UEs on both uplink and downlink. - Compression, encryption, and data integrity protection of the IP header. - Selection of AMF when UE connection is not possible based on the information provided by the UE. - Routing user plane data to UPF(s) - Routing of control plane information to AMF - Setting up and releasing the connection - Scheduling and sending paging messages - Scheduling and transmission of system broadcast information (originating from AMF or OAM) - Setting up measurements and measurement reporting for mobility and scheduling. - Transport-level packet marking on the uplink - Session management - Support for network slicing - QoS flow management and mapping to data radio bearers - Support for UEs in RRC_INACTIVE state - NAS (Non-access stratum) message delivery function - Wireless access network sharing - Dual connectivity - Close cooperation between NR and E-UTRA

[0024] The Access and Mobility Management Function (AMF) hosts the following main functions: - Non-accessible layer NAS signaling termination - NAS signaling security - Access Layer AS Security Management - Core network CN node inter-signaling for mobility between 3GPP access networks - Reachability of UE in idle mode (including control and execution of paging retransmissions) - Registration area management - Support for mobility within and between systems - Access Authentication - Access authorization including roaming rights checks - Mobility management and control (subscriptions and policies) - Support for network slicing - Selection of Session Management Function (SMF)

[0025] Furthermore, the User Plane Function UPF hosts the following main functions: - Anchor points for mobility within / between RATs (if applicable) - External PDU session points for interconnection to the data network - Packet routing & forwarding - User plane portion of packet inspection and policy rule enforcement - Report traffic usage - Uplink classifier that supports routing of traffic flow to data networks. - Branch point to support multi-homed PDU sessions - User plane QoS handling, e.g., packet filtering, gating, UL / DL rate enforcement. - Uplink traffic verification (mapping from SDF to QoS flow) - Buffering downlink packets and triggering downlink data notifications

[0026] Finally, the session management function SMF hosts the following main functions: - Session management - Assignment and management of UE IP addresses - Selection and control of UP function - Configuring traffic steering in the user plane feature UPF to route traffic to the appropriate destination. - Policy enforcement and QoS control section - Downlink data notification

[0027] RRC Connection Setup and Reconfiguration Procedure

[0028] Figure 3 shows some interactions between the UE, gNB, and AMF (5GC entity) in the context of the UE transitioning from RRC_IDLE to RRC_CONNECTED with respect to the NAS part (see Non-Patent Document 1).

[0029] RRC is a higher-layer signaling (protocol) used for configuring UEs and gNBs. Specifically, this transition involves the AMF preparing UE context data (including, for example, PDU session context, security key, UE radio capability, and UE security capability) and sending this to the gNB using an initial context setup request. The gNB then activates AS security with the UE, which is done by the gNB sending a SecurityModeCommand message to the UE, and the UE responding to the gNB with a SecurityModeComplete message. Subsequently, the gNB performs a reconfiguration, setting up the Signaling Radio Bearer 2 (SRB2) and the Data Radio Bearer(s) (DRB(s)) by sending an RRCReconfiguration message to the UE, and the gNB receiving an RRCReconfigurationComplete from the UE accordingly. In the case of a signaling-only connection, SRB2 and DRB are not set up, so the steps related to RRCReconfiguration are skipped. Finally, the gNB informs the AMF that the setup procedure is complete using the initial context setup response.

[0030] Therefore, this disclosure provides a fifth-generation core (5GC) entity (e.g., AMF, SMF, etc.) that includes a control circuit for establishing a next-generation (NG) connection with the gNodeB during operation, and a transmitter for sending an initial context setup message to the gNodeB via the NG connection during operation, causing the gNodeB and the user equipment (UE) to set up the signaling radio bearer. Specifically, the gNodeB sends radio resource control (RRC) signaling, including resource allocation setting information elements, to the UE via the signaling radio bearer. The UE then performs uplink transmission or downlink reception based on the resource allocation setting.

[0031] IMT usage scenarios from 2020 onwards

[0032] Figure 4 illustrates some use cases for 5G NR. The 3rd Generation Partnership Project New Radio (3GPP NR) is exploring three use cases where IMT-2020 is expected to support a wide variety of services and applications. Phase 1 specifications for Enhanced Mobile Broadband (eMBB) have been finalized. In addition to further expanding eMBB support, current and future work will include standardization of Ultra-Reliable Low-Latency Communications (URLLC) and Massive Machine-Type Communications. Figure 4 shows some examples of anticipated use scenarios for IMT beyond 2020 (see, for example, Figure 2 in Non-Patent Document 3).

[0033] 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, power distribution automation in smart grids, and transportation safety. The ultra-high reliability of URLLC is supported by identifying technologies that meet the requirements set out in Non-Patent Document 4. For NR URLLC of Release 15, key requirements include a target user plane latency of 0.5 ms for UL (uplink) and 0.5 ms for DL ​​(downlink). Typical URLLC requirements for a single packet transmission are a BLER (block error rate) of 1E-5 for a 32-byte packet size with a user plane latency of 1 ms.

[0034] From a physical layer perspective, reliability can be improved in several possible ways. The current scope of reliability improvements includes defining a separate CQI table for URLLC, a more compact DCI (Downlink Control Information) format, and PDCCH iteration. However, as NR evolves to be more stable (with respect to the main requirements of NR URLLC), this scope may expand to achieve ultra-high reliability. Specific use cases for NR URLLC in Release 15 include Augmented Reality / Virtual Reality (AR / VR), e-health, e-safety, and mission-critical applications.

[0035] Furthermore, the technical enhancements targeted at NR URLLC are aimed at improving latency and reliability. Technical enhancements for latency improvement include configurable neurology, non-slot-based scheduling with flexible mapping, grant-free (configured grant) uplinks, slot-level iteration for data channels, and downlink preemption. Preemption means that a transmission for which resources have already been allocated is stopped, and the allocated resources are used for other transmissions that are requested later but have lower latency / higher priority requirements. Thus, transmissions that have already been granted are preempted by later transmissions. Preemption is applicable regardless of the specific service type. For example, a transmission of service type A (URLLC) may be preempted by a transmission of service type B (e.g., eMBB). Technical enhancements for reliability improvement include a dedicated CQI / MCS table for target BLER 1E-5.

[0036] Use cases for mMTC (Massive Machine Type Communications) are typically characterized by a very large number of connected devices transmitting relatively small amounts of latency-insensitive data. These devices need to be inexpensive and have very long battery life. From a noise reduction (NR) perspective, utilizing a very narrow bandwidth portion is one possible solution for saving power and achieving long battery life from a user interface (UE) perspective.

[0037] As mentioned above, the scope of NR reliability is expected to broaden. One major requirement for all cases, particularly for URLLC and mMTC, is high or very high reliability. Several mechanisms can be considered to improve reliability from both a radio and network perspective. In general, there are several key potential areas that can help improve reliability. Among these areas are compact control channel information, data / control channel repetition, and diversity in the frequency, time, and / or spatial domains. These areas are generally applicable to reliability and are not dependent on specific communication scenarios.

[0038] For NR URLLC, further use cases with more stringent requirements have been identified, including factory automation, the transportation industry, and power distribution. These stringent requirements, depending on the use case, require higher reliability (up to 10%). -6 This level includes higher availability, a maximum packet size of 256 bytes, time synchronization to the order of a few microseconds, which can be 1 μs or several microseconds depending on the frequency range, and low latency on the order of 0.5 to 1 ms, particularly a target user plane latency of 0.5 ms.

[0039] Furthermore, in the case of NR URLLC, several technical enhancements from a physical layer perspective have been identified. These include enhancements to the PDCCH (Physical Downlink Control Channel) related to a compact DCI, PDCCH repeating, and enhanced PDCCH monitoring. Enhancements to the UCI (Uplink Control Information) relate to enhanced HARQ (Hybrid Automatic Repeat Request) and CSI feedback. Additionally, enhancements to the PUSCH have been identified related to mini-slot level hopping and retransmission / repeat enhancements. The term "mini-slot" refers to a Transmission Time Interval (TTI) containing fewer symbols than a slot (a slot containing 14 symbols).

[0040] In slot-based scheduling or assignment, a slot corresponds to the timing granularity (TTI: transmission time interval) of the scheduling assignment. Generally, the TTI determines the timing granularity of the scheduling assignment. One TTI is the time interval at which a given signal is mapped to the physical layer. For example, conventionally, the TTI length can vary from 14 symbols (slot-based scheduling) to 2 symbols (non-slot-based scheduling). Downlink (DL) and uplink (UL) link transmissions are specified to be organized into frames (10 ms duration) consisting of 10 subframes (1 ms duration). In slot-based transmission, subframes are further divided into slots, and the number of slots is defined by the neurology / subcarrier interval. Specified values ​​range from 10 slots per frame (1 slot per subframe) when the subcarrier interval is 15 kHz to 80 slots per frame (8 slots per subframe) when the subcarrier interval is 120 kHz. The number of OFDM symbols per slot is 14 for a normal cyclic prefix and 12 for an extended cyclic prefix (see Sections 4.1 (general frame structure), 4.2 (Numerologies), 4.3.1 (frames and subframes), and 4.3.2 (slots) of Physical channels and modulation, 2018-09, Non-Patent Literature 5). However, time resource allocation for transmission may be non-slot-based. Specifically, TTI in non-slot-based allocation may correspond to minislots rather than slots; that is, one or more minislots may be allocated to the transmission of requested data / control signaling. In non-slot-based allocation, the minimum TTI length may be, for example, 1 or 2 OFDM symbols.

[0041] QoS control

[0042] The 5G Quality of Service (QoS) model is based on QoS flows and supports both QoS flows that require a guaranteed flow bitrate (GBR: guaranteed bit rate QoS flows) and QoS flows that do not require a guaranteed flow bitrate (non-GBR QoS flows). Therefore, at the NAS level, QoS flows are the finest granularity of QoS differentiation within a PDU session. QoS flows are identified within a PDU session by a QoS flow ID (QFI: QoS flow ID) carried in an encapsulation header via the NG-U interface.

[0043] For each UE, the 5GC establishes one or more PDU sessions. For each UE, the NG-RAN establishes at least one data radio bearer (DRB) with the PDU session, and may later configure additional DRBs for the QoS flow(s) of that PDU session, as shown above, for example, with reference to Figure 3 (when this is done is up to the NG-RAN). The NG-RAN maps packets belonging to different PDU sessions to different DRBs. NAS-level packet filters in the UE and 5GC associate UL and DL packets with QoS flows, and AS-level mapping rules in the UE and NG-RAN associate UL and DL QoS flows with DRBs.

[0044] Figure 5 shows a 5G NR non-roaming reference architecture (see Section 4.23 of Non-Patent Literature 6). An Application Function (AF), such as an external application server hosting a 5G service as illustrated in Figure 4, interacts with the 3GPP core network to provide services and supports, for example, application influence on traffic routing, access to Network Exposure Functions (NEFs), or interaction with a policy framework for policy control such as QoS control (see Policy Control Function (PCF)). Based on the operator's placement, application functions deemed trusted by the operator may be permitted to interact directly with the relevant network functions. Application functions not permitted by the operator to directly access network functions interact with the relevant network functions using the Network Exposure Framework via the NEF.

[0045] Figure 5 shows further functional units of the 5G architecture, namely the 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 may be deployed and run in a cloud computing environment.

[0046] Therefore, this disclosure provides an application server (e.g., AF in a 5G architecture) that, in operation, sends a request to at least one of the 5GC functions (e.g., NEF, AMF, SMF, PCF, UPF, etc.) including QoS requirements for at least one of the URLLC, eMMB, and mMTC services to establish a PDU session including a radio bearer between the gNodeB and UE in accordance with the QoS requirements, and in operation, a control circuit that performs a service using the established PDU session.

[0047] In LTE and NR, terminals are called user devices (UEs). These can be mobile devices or communication devices such as wireless phones, smartphones, tablet computers, or USB (Universal Serial Bus) sticks that have the functionality of a user device. However, the term mobile device is not limited to these, and generally, repeaters may also have the functionality of such mobile devices, and mobile devices may function as repeaters.

[0048] A base station is a network node or scheduling node that forms part of a network to provide services to terminals, for example. A base station is a network node that provides wireless access to terminals.

[0049] Figures 6-9 show some additional examples of interactions between the AMF and UE and NG-RAN nodes (e.g., gNB) compared to the example in Figure 3.

[0050] Specifically, Figure 6 illustrates the registration procedure, in which a registration request is sent from the UE to the AMF, and in response, the AMF sends a registration acceptance message. For example, the UE may initiate a registration procedure for initial registration, mobility registration renewal, or periodic registration renewal.

[0051] On the other hand, if AMF wants to update UE settings related to access and mobility parameters, for example, it can initiate a UE setting update procedure, as shown in Figure 7. As shown in Figure 7, AMF sends a setting update command, to which the UE responds with a setting update complete message.

[0052] Figure 8 shows the NG setup procedure between the NG-RAN node and the AMF. Specifically, the NG-RAN node (e.g., gNB) sends an NG setup request to the AMF and receives an NG setup response from the AMF. The NG setup procedure can be used to exchange application-level data (e.g., configuration data) necessary for the NG-RAN node and the AMF to properly interoperate on the NG interface.

[0053] Furthermore, a RAN configuration update procedure may be used to update application-level configuration data necessary for NG-RAN nodes and AMFs to properly interoperate on the NG interface. As shown in Figure 9, a RAN configuration update procedure may include an NG-RAN node sending a RAN configuration update and receiving a RAN configuration update acknowledgment in response.

[0054] RRC status

[0055] In wireless communication systems, including NR, a device or communication equipment (e.g., UE) can be in different states depending on traffic 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 the same as their counterparts in LTE, while RRC_INACTIVE is a new state introduced in NR and does not exist in the original LTE design. There are also core network states, CN_IDLE and CN_CONNECTED, which depend on whether the device has established a connection with the core network or not.

[0056] In RRC_IDLE, the RRC context—that is, the parameters necessary for communication between the device and the network—does not exist in the radio access network, and the device does not belong to a specific cell. From the core network's perspective, the device is in the CN_IDLE state. Data transfer may not occur as the device sleeps most of the time to reduce battery consumption. Downlink, an idle device wakes up periodically to receive paging messages from the network if available. Mobility is handled by the device through cell reselection. Uplink synchronization is not maintained, and therefore the only uplink transmission activity that can occur is random access, such as transitioning to a connected state. As part of the transition to a connected state, the RRC context is established on both the device and the network.

[0057] In RRC_CONNECTED, an RRC context is established, and all parameters necessary 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 a Cell Radio-Network Temporary Identifier (C-RNTI), which is the device's identification information used for signaling between the device and the network, is set. The connected state is intended for data transfer between the device and the network, but discontinuous reception (DRX) can be set to reduce the device's power consumption. In the connected state, the gNB has an established RRC context, so initiating data transmission and reception after leaving DRX is relatively fast because it does not require the associated signaling connection setup. Mobility is managed by the radio access network; that is, the device provides the network with measurements of neighboring cells, and the network instructs the device to perform handovers where applicable. Uplink time alignment may or may not exist, but it must be established and maintained using random access for data transmission to take place.

[0058] LTE only supports idle and connected states. A common practice is to use the idle state as the primary sleep state to reduce device power consumption. However, frequent transmission of small packets is common in many smartphone applications, resulting in a significant amount of transitions from idle to active in the core network. These transitions come at the cost of signaling load and associated latency. Therefore, to reduce signaling load and generally latency, NR defines a third state, the RRC_INACTIVE state.

[0059] In RRC_INACTIVE, the RRC context is maintained by both the device and the gNB. Core network connectivity is also maintained; i.e., the device is in CN_CONNECTED from the perspective of the core network. Therefore, the transition to a connected state for data transfer is fast. Core network signaling is not required. The RRC context is already in place within the network and can handle the transition from idle to active within the radio access network. At the same time, the device can sleep in a manner similar to the idle state, and mobility is handled through cell reselection, i.e., without network involvement. Therefore, the mobility of the communication device or device is device-controlled, not network-controlled, and the communication device can access the network via random access. Thus, RRC_INACTIVE can be considered a mixture of idle and connected states (see sections 6.5.1-6.5.3 of Non-Patent Literature 7 for details).

[0060] Paging procedure for 5G NR

[0061] A simplified, abbreviated description below illustrates an exemplary implementation of paging functionality in 5G NR, including PDCCH monitoring, in accordance with the currently standardized version.

[0062] 5G NR has two different paging procedures: a RAN-based paging procedure (e.g., based on a RAN-based notification area) and a core network-based paging procedure (see, for example, Non-Patent Documents 1, 8, and 9, which refer to RAN paging and CN paging in several sections, such as section 9.2.5 "Paging" of Non-Patent Document 1).

[0063] Paging allows the network to reach UEs in RRC_IDLE and RRC_INACTIVE states via paging messages, and enables notification of system information changes and public warning information (e.g., ETWS / CMAS, Earthquake and Tsunami Warning System / Commercial Mobile Alert System) to UEs in RRC_IDLE, RRC_INACTIVE, and RRC_CONNECTED states via short messages. Both paging messages and short messages are addressed by P-RNTI on the PDCCH monitored by the UE. However, while the actual paging message (e.g., including the paging record) is subsequently sent via the PCCH (as indicated by the PDCCH), short messages can be sent directly via the PDCCH.

[0064] In RRC_IDLE mode, the UE monitors the paging channel for paging initiated by the CN, while in RRC_INACTIVE mode, 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; if a paging DRX is defined, the UE in RRC_IDLE or RRC_INACTIVE mode only needs to monitor the paging channel during one paging occasion (PO) per DRX cycle (see Non-Patent Document 10, e.g., sections 6.1 and 7.1). The paging DRX cycle is set by the network.

[0065] UE POs in CN-initiated and RAN-initiated paging are based on the same UE ID, so both POs overlap. The number of different POs within a DRX cycle is configurable via system information, and the network can distribute UEs to those POs based on their IDs. A PO is a set of PDCCH monitoring occasions and can consist of multiple time slots (e.g., subframes or OFDM symbols) from which paging DCIs can be sent. A paging frame (PF) is a single radio frame and may contain one or more POs or PO initiation points.

[0066] In the case of RRC_CONNECTED, the UE monitors the paging channel for System Information (SI) change notifications and / or Public Warning System (PWS) notifications at POs signaled with System Information. In the case of Bandwidth Adaptation (BA) (see Section 6.10 of Non-Patent Document 1), the UE in RRC_CONNECTED monitors only the paging channel on the active BWP where the common search space is configured.

[0067] If the UE receives a paging message, PDCCH monitoring can be stopped by the UE. Depending on the cause of the paging, the UE may continue, for example, by obtaining system information or by establishing an RRC connection with the base station to receive traffic / commands from the network.

[0068] Tracking area and tracking area code

[0069] Since the location of the UE is typically known at the cell level, paging messages are typically sent across multiple cells within a so-called tracking area (TA), which can be controlled by the AMF / MME (Mobility Management Entity).

[0070] A group of neighboring gNBs can be defined as a TA (Tracking Area). This definition may be performed, for example, during the initial deployment of the network, and each gNB may be assigned its own TA. A tracking area code (TAC) is a unique code assigned to each TA.

[0071] Since the network needs to have updated location information about UEs in RRC_IDLE to determine which TA a particular UE is located within, a UE can notify the network of its current location by sending a tracking area update (TAU) message each time it moves between TAs.

[0072] For this purpose, when a UE connects to the network, a list is obtained showing the TAs that the network believes the UE is located in. If the UE moves within the TAs shown in the list above, the TAU procedure does not need to be performed. However, if the UE moves to a TA not shown in the list above, the TAU procedure is initiated.

[0073] Furthermore, an UE in RRC_IDLE mode may send TAU messages regularly and periodically, even if the UE remains within the same TA. By regularly providing TAU messages, the network can be notified that the UE is still available and can receive data.

[0074] The tracking area code associated with a cell can be broadcast in the system information by each gNB.

[0075] Registration area

[0076] As described above, to efficiently page UEs when they are idle, tracking area (TA) is used to track UE mobility at the core network level (e.g., by AMF). Each UE contains a list of TAIs (tracking area identifiers) (e.g., as the TA list above). Registration Area (RA) This is allocated by the core network. Generally, registration areas are UE-specific and can differ from UE to UE even in similar locations (for example, due to load balancing).

[0077] If the core network needs to page a UE (for example, if there is downlink data to send to the UE), it sends a paging message to one or more gNBs, and one or more gNBs perform paging of the UE in all cells belonging to the registration area.

[0078] Figure 10 shows the relationship between registration areas, tracking areas, and cells, where both tracking areas TAI1 and TAI2 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 a gNB (or base station) and a cell, and a gNB may also serve multiple cells.

[0079] When a UE moves to a cell outside the area defined by the RA, it must access the network and perform a mobility registration renewal procedure. If the registration procedure shown in Figure 6 is used in the mobility renewal procedure, the UE reports the TAI to the network via a registration request message. The core network then provides the UE with a new TAI list containing the new TAI in a registration acceptance message. In this way, the UE is assigned a new registration area.

[0080] Therefore, when moving to a new cell, the UE needs to determine whether it is still within the same RA. To know whether it is still within the same RA, the UE considers the TAC associated with the cell. Each cell broadcasts its associated TAC (the tracking area code of the TA to which the cell belongs) and PLMN ID (public land mobile network identity) in its system information (e.g., SIB1, i.e., system information block 1). When the UE visits or camps in a new cell, the UE reads the system information and derives the TAI by cascading the TAC with the PLMN ID or by appending the TAC to the PLMN ID (TAI = PLMN ID + TAC). The UE then compares the derived TAI to the list of TAIs in the RA. Here, "camping" in a cell includes at least one of the following: initiating paging monitoring, reading the SIB from the cell, and performing measurements using the RS from the cell.

[0081] Non-terrestrial network (NTN)

[0082] 3GPP has studied and described NR-based operation in non-terrestrial networks (NTN) (see, for example, Non-Patent Documents 11 and 12).

[0083] Thanks to its broad service coverage capabilities and the mitigated vulnerability of spacecraft / aircraft to physical attacks and natural disasters, NTN can facilitate the deployment of NR services to underserved areas that are not covered by terrestrial NR networks (e.g., isolated or remote areas, on aircraft or ships) and where services are not available (e.g., suburban and rural areas). Furthermore, NTN can enhance the reliability of NR services by providing service continuity for passengers on moving platforms and ensuring service is available everywhere, especially for critical communications.

[0084] The advantages relate to either standalone non-terrestrial networks or integrated terrestrial and non-terrestrial networks, which can impact coverage, user bandwidth, system capacity, and service reliability or availability.

[0085] A non-terrestrial network refers, for example, to a network or segment of a network that uses RF resources onboard a satellite. NTN typically features the following system elements: NTN terminals, which may refer to a 3GPP UE or, if the satellite does not directly service a 3GPP UE, terminals specific to the satellite system; service links, which refer to radio links between user equipment and space / air platforms; air platforms carrying payloads; gateways connecting the space / air platforms to the core network; and feeder links, which refer to radio links between gateways and space / air platforms.

[0086] Figure 11 illustrates a non-terrestrial network scenario in which transmission between a satellite and a terminal (UE) is performed via a remote radio unit including an NTN gateway. A gNB is positioned at the gateway as a scheduling device. The satellite payload implements frequency conversion and radio frequency amplification in both the uplink and downlink directions. Thus, 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. A satellite in this configuration is called a transparent satellite.

[0087] Figure 12 illustrates a non-terrestrial network scenario in which transmission between a terminal (UE) and a satellite is performed via a satellite containing a gNB as a scheduling device. Satellites in this configuration are called regenerative satellites.

[0088] NTN may have various types of platforms, including satellite and UAS (Unmanned Aerial System) platforms, examples of which are listed in Table 1 (corresponding to Table 4.1-1 in Non-Patent Literature 12, and also refer to the Non-Terrestrial Networks overview in Section 4.1 of Non-Patent Literature 12).

[0089] [Table 1]

[0090] For LEO, MEO, and HEO satellites, which 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 the SSB (Synchronization Signal Block) beam of the NR wireless system may move on Earth.

[0091] Regarding the mapping between satellite beams, NR cells, and NR SSB beams, different deployment options are possible, such as options a and b shown in Figures 13 and 14. According to deployment option a shown in Figure 13, one cell (corresponding to a PCI) has multiple satellite beams (e.g., the same PCI for multiple satellite beams), while according to deployment option b shown in Figure 14, one cell corresponds to one satellite beam (one PCI exists for each satellite beam).

[0092] A satellite beam can consist of one or more SSB beams. For example, one satellite beam can be mapped to one SSB beam, so that there is a one-to-one correspondence between the satellite beam and the SSB beam. Here, the beam used to transmit the NR synchronization signal block is referred to as the SSB beam. A single NR cell (PCI) can have up to L SSB beams, where L can be 4, 8, or 64 depending on the bandwidth. The SSB beam can be used as a reference beam for beam management in the NR.

[0093] An NTN scenario that provides a continuously moving cell on Earth (e.g., LEO, MEO, or HEO-based NTN) is called a Earth-moving cell scenario. A Earth-moving cell scenario is shown in Figure 15. The continuous movement of the cell on Earth is due to the operation of the satellite beam being fixed relative to the NTN platform. Therefore, the cell footprint, which can accommodate several satellite beams or one satellite beam according to deployment options a and b described above, slides on the Earth's surface as the NTN platform (e.g., the LEO satellite shown in Figure 15) moves.

[0094] Information regarding a satellite's orbital trajectories is contained in ephemeris data (or "satellite ephemeris data"). Various possible representations of ephemeris data exist, one possibility being to use orbital parameters such as semi-major axis, eccentricity, inclination angle, right ascension of the ascending node, argument of periphery, mean angle of periphery at a reference time, and epoch. The first five parameters can determine the orbital plane (orbital plane parameters), while the other two parameters are used to determine the exact satellite position at a given time (satellite level parameters). The orbital plane parameters and satellite level parameters are listed in Table 2 and shown in Figure 16 (see also Representation of Complete Ephemeris Data in Section 7.3.6.1 of Non-Patent Literature 12). Other possible options include providing the satellite position coordinates (x,y,z), velocity vector (vx,vy,vz), and reference time.

[0095] [Table 2]

[0096] Therefore, representing ephemeris data may require seven parameters (e.g., double-precision floating-point numbers) and possibly some overhead. In NTN systems, several satellites may share a common orbital plane. In such cases, to reduce the amount of data, some ephemeris data may be provided for the orbital plane rather than for a single satellite. Ephemeris data per orbital plane may be stored in the UE or the UE's Subscriber Identity Module (SIM).

[0097] However, in the case of a network with many satellites, the size of ephemeris data can be quite large. Therefore, instead of storing the ephemeris data, it may be transmitted from the gNB, at least partially.

[0098] For example, satellite-level orbital parameters for all satellites that can service a UE may 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 a service-providing satellite may then be broadcast in the system information, and as a result, the UE can find the corresponding ephemeris data in the UE's SIM or storage.

[0099] Alternatively, satellite-level orbital parameters of the service provider satellite may be broadcast in the system information, and the UE derives the position coordinates of the service provider satellite. Ephemeris data of nearby satellites can also be provided to the UE via system information or dedicated RRC signaling. If baseline orbital plane parameters are provisioned to the UE or SIM, it may be sufficient to broadcast only the mean angle of perigee at the reference point, reducing overhead as the epoch does not need to be broadcast to the UE.

[0100] As described above with reference to Figure 15, the Earth-moving cell scenario is an NTN scenario that provides a cell that continuously moves on Earth. This is due to the operation in which the satellite beam is fixed to the NTN platform. Therefore, the footprint of the satellite beam slides on the Earth's surface as the NTN platform (e.g., the LEO satellite) moves.

[0101] As mentioned above, there is an association between the cell and the tracking area. However, in a moving 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 needs to continue performing frequent registration updates, which results in additional overhead and power consumption.

[0102] For these reasons, instead of a moving tracking area, a fixed tracking area can be considered for NTN. Thus, the tracking area corresponds to a fixed geographical location on Earth. For a moving cell, a fixed TA can be implemented in two ways. According to one approach, the TAC broadcast by the (moving) cell changes as that cell covers different geographical areas. According to the other approach, the TAC is not broadcast, and the UE derives the registered area in another way, for example, from its own location information.

[0103] Regarding the mapping between cells and tracking areas, "hard switch" and "soft switch" options are possible. A hard switch means that a single cell broadcasts only one TAC per PLMN. When a new TAC replaces an old TAC in a cell, some fluctuation may occur in the boundary area between TAs. On the other hand, the "soft switch" option allows a single cell to broadcast two or more TACs per PLMN. The cell adds the new TAC to the system information along with the old one, and then removes the old one a short time later. However, signaling more TACs can increase overhead (see also section 7.3.1.3.1 of Non-Patent Literature 12 for more on hard and soft switches).

[0104] The following details some aspects of location-based TA determination. Specifically, it is conceivable to divide the Earth into multiple geographic areas corresponding to TA. Mapping rules between geographic areas and their associated TAC values ​​may further be maintained in both the UE and the network.

[0105] For example, during initial registration, the UE derives a TAC based on its location information and mapping rules, and then forms a TAI from the derived TAC and the broadcasted PLMN ID. The UE then reports the TAI to the AMF via a registration request message. The AMF then provides the UE with a TAI list containing the reported TAI via a registration acceptance message.

[0106] When a UE moves to a new geographic area, the UE derives a TAC based on its location information and mapping rules, and then forms a TAI from the TAC and the broadcasted PLMN ID. If the formed TAI is not in the TAI list, the mobility registration update procedure is triggered. At this time, the UE reports the TAI to the AMF via a registration request message. The AMF provides the UE with a TAI list containing the reported TAI via a registration acceptance message. The UE then replaces the old TAI list with a new one containing the reported TAI (see also section 7.3.1.3.2 of Non-Patent Document 12).

[0107] Regarding the TA determination mechanism described above, it is generally unclear how the mapping rules between geographical areas and TACs become available to the UE. Furthermore, in specific cases, such as when cell selection or reselection is based on radio signal strength and the TAC is not broadcast, for example when positioning is unavailable, it is unclear how to determine that the UE is still within the RA.

[0108] Furthermore, due to the movement of cells, there is no fixed relationship between cells and registration areas. When the core network needs to page UEs, it is unclear what information is required for the AMF to select the gNB(s) to deliver the paging message to, and for the gNB(s) to select the cell(s) to page the UEs to, and how such information is obtained.

[0109] This disclosure pertains to the determination of tracking areas and handling of paging for non-terrestrial networks.

[0110] This disclosure describes scheduling nodes such as UEs and base stations, as well as corresponding methods, which are intended for new radio access technologies intended for 5G mobile communication systems such as 3GPP NR, but may also be used in LTE mobile communication systems.

[0111] Therefore, communication equipment (or user terminals or communication terminals) is called UE (User Equipment), and scheduling nodes such as base stations may correspond to gNodeB (gNB).

[0112] Furthermore, while some of the terms used below, such as procedures, entities, and layers, are closely related to those used in LTE / LTE-A systems or current 3GPP 5G standardization, certain terms used in the context of new radio (NR) access technologies for the following 3GPP 5G communication systems are not yet fully determined or may ultimately change. Therefore, terms may change in the future without affecting the functionality of the embodiments. Accordingly, those skilled in the art will recognize that the embodiments and the scope of their protection should not be limited to certain terms used exemplary herein because there are no newer or ultimately agreed-upon terms.

[0113] Communication equipment or devices such as UEs, and scheduling nodes or base stations, may include circuits such as transceivers and processing circuits. By extension, transceivers may include and / or function as receivers and transmitters. Processing circuits may be one or more processors or one or more hardware such as any LSI (Large Scale Integration). There are input / output points (or nodes) between the transceivers and processing circuits, through which the processing circuits can, in operation, control the transceivers, i.e., control the receiver and / or transmitter, and exchange received / transmitted data. Transceivers may include an RF (radio frequency) front, including one or more antennas, amplifiers, RF modulators / demodulators, etc., as transmitters and receivers. Processing circuits may perform control tasks, for example, controlling transceivers to transmit user data and control data provided by the processing circuits, and / or to receive user data and control data that is further processed by the processing circuits. Processing circuits may also be responsible for performing other processes, for example, determining, deciding, calculating, and measuring. 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.

[0114] Communication equipment such as UEs and base stations, as well as core network entities such as AMF systems, may include circuits, which may include processing circuits and control circuits.

[0115] A user device (UE) 1770 is provided. As shown in Figure 17, the UE includes a transceiver 1780, which transmits a registration request during operation. The registration request (or "registration request message") is: • Notification of the UE's first position, or • The cell ID of the last cell visited by the UE, and a timestamp indicating the first time the UE was located within that last cell. It includes at least one of the following.

[0116] The transceiver 1780 of UE1770 (or "UE transceiver") receives a registration acceptance message that includes a registration area (RA), the registration area including the first location of the UE.

[0117] UE1770 further comprises circuit 1790 (or "UE circuit"), which, in operation, determines whether the UE is located within the registration area at a second position. The determination of whether the UE is located within the registration area is made based on at least one of the following: • A list of cell IDs for multiple Earth-moving cells or cell sections of Earth-moving cells; a notification of the second time when multiple Earth-moving cells form a registration area; for each of the multiple Earth-moving cells, coverage area information and satellite ephemeris data indicating the coverage area of ​​the cell or cell section relative to the satellite position of the satellite generating the cell, and a measurement of the second position of the UE. The list of multiple Earth-moving cells and the notification of the second time are included in the registration area notification. Or, • A list of cell IDs, a notification of the time interval in which multiple Earth-moving cells or cell sections form a registration area, and the cell ID of the newly visited cell or cell section, which is different from the last cell, including the second location of the UE. The list of cell IDs and the notification of the time interval are included in the registration area notification. Or, • Measurements of the second location, mapping between geographical areas and tracking areas, and a list of one or more tracking areas that form the registration area. The mapping is read from storage, and the list of one or more tracking areas is included in the registration area notification.

[0118] User device 1770 is a mobile device, communication device, or mobile terminal of a wireless communication system.

[0119] For example, the UE circuit 1790 may include an RA position determination circuit 1795. An exemplary RA position determination circuit 1795 is shown in Figure 18, which includes an RA determination circuitry 1896 and an RA decision circuitry 1897.

[0120] A base station 1740 is further provided, also shown in Figure 17. The base station 1740 is equipped with interface 1755 (also referred to as the “base station interface”), which, in operation, receives paging requests for paging UEs. Paging requests include notification of registration areas. The base station is further equipped with circuit 1760 (the “base station circuit”), which, in operation, Based on a list of cell IDs of a first set of multiple Earth-moving cells or cell sections of Earth-moving cells, a second time notification of when the first set of multiple Earth-moving cells form a registration area, and for each of the first set of multiple Earth-moving cells, coverage area information indicating the coverage area of ​​the cell or cell section relative to the satellite position of the satellite generating the cell, and satellite ephemeris data (the list of the first set of multiple Earth-moving cells and the time notification are included in the registration area notification), or Based on a list of cell IDs and a notification of the time intervals in which the first multiple Earth-moving cells or cell sections form a registration area (the list of cell IDs and the notification of time intervals are included in the registration area notification), or Based on the mapping between geographical areas and tracking areas, and a list of one or more tracking areas that make up the registration area (the mapping is read from storage, and the list of one or more tracking areas is included in the registration area notification), A second set of Earth-moving cells is determined. The second set of Earth-moving cells is a set of cells currently mapped to the registration area. The base station 1740 further comprises a transceiver 1750 that, in operation, transmits paging messages for paging UEs within the second set of cells.

[0121] For example, the base station circuit 1760 includes an RA decision circuit 1765.

[0122] Base station 1740 is a scheduling node or scheduling device for a wireless communication system such as a 3GPP NR gNB on which a non-terrestrial network is implemented. Thus, the Earth mobile cell is serviced by a satellite (e.g., LEO) or other non-terrestrial platform such as an airship or balloon. For example, the communication system is an NR-NTN communication system. The communication system may include the Earth mobile cell alone, or in combination with or supplementing fixed cells generated, for example, by a ground base station. UE 1770 and base station 1740 communicate via a wireless channel. This disclosure is not limited to a specific relationship between a base station and a satellite, and communication systems implementing both regenerative and transparent satellites, or both regenerative and transparent satellites, as shown in Figures 11 and 12, are possible.

[0123] Furthermore, the base station communicates with core network entities or systems such as the AMF via interface 1755.

[0124] In the above description of the base station, "first set of cells" refers to the Earth-moving cells that define the registration area by associating the first set of cells with information about the time (time or time interval) that constitutes the registration area. On the other hand, "second set of cells" refers to the cells on which the UE is paged. As will be explained further, the second set of cells is determined based on the first set of cells.

[0125] A base station may serve one cell or two or more cells. Furthermore, the registration area may be larger than the number of cells served by base station 1740. Therefore, the "second multiple cells" determined by the base station to page the UE may cover the entire registration area or a sub-area of ​​the registration area.

[0126] As shown in Figure 17, an AMF (Access Mobility and Management Function) system 1710 is also disclosed. The AMF system 1710 comprises an interface 1720 ("AMF interface") and a circuit 1730 (AMF circuit). When the AMF interface 1720 is in operation, it receives a registration request from the UE, and the registration request is, • Notification of the UE's first position, or • The cell ID of the last cell visited by the UE, and a timestamp indicating the first time the UE was located within that last cell. Includes.

[0127] The AMF circuit 1730 generates a registration area notification that includes the first location of the UE. The registration area notification is, • Includes a list of cell IDs for multiple Earth-moving cells or cell sections of Earth-moving cells, and a notification of a second time when the multiple Earth-moving cells form a registration area (the registration area is determined for each of the multiple Earth-moving cells or cell sections based on coverage area information indicating the coverage area of ​​the cell or cell section relative to the satellite position of the satellite generating the cell, and satellite ephemeris data), or, • Includes a list of cell IDs and a notification of the time intervals in which multiple Earth-moving cells or cell sections form a registration area, or • Includes a list of one or more tracking areas that make up the registration area (the list of one or more tracking areas is determined based on the mapping between geographical areas and tracking areas, and the mapping is read from storage).

[0128] The AMF interface 1720 sends a registration acceptance message, including a notification of the registration area, when it is in operation.

[0129] The AMF system 1710 is an AMF entity of a core network, such as a fifth-generation core. For example, the AMF system may be implemented as a server, or within a server hosting further core network entities, or distributed across multiple nodes.

[0130] The AMF system 1710 and the base station 1740 communicate via interfaces 1720 and 1755. For example, interfaces 1720 and 1755 form an NG interface. The AMF system 1710 and the base station 1740 can communicate via interfaces 1720 and 1755 by a wired connection (which may include fiber optic cables) or a wireless connection (such as in a regenerative satellite scenario). The base station interface 1755 may be included in the base station transceiver 1750 or may be separate from the base station transceiver 1750.

[0131] For example, as shown in Figure 17, the AMF circuit 1730 includes an RA determination circuit 1735.

[0132] As described above, UE1770 and AMF1710 exchange registration request messages and registration acceptance messages. This exchange may be performed via base station 1740, which may forward these control messages for the registration procedure. In this case, base station transceiver 1750 may receive a registration request message from the UE and send a registration acceptance message to the UE during operation. Similarly, base station interface 1755 may send a registration request message to the AMF and receive a registration acceptance message from the AMF.

[0133] In accordance with the user equipment described above, a communication method for the user equipment (UE) is provided. As shown in Figure 19, this method includes step S1910 of sending a registration request, the registration request is • Notification of the UE's first position, or • The cell ID of the last cell visited by the UE, and a timestamp indicating the first time the UE was located within that last cell. It includes at least one of the following.

[0134] This method includes a step S1920 in which a registration acceptance message is received, which includes a notification of the registration area, and the registration area includes a first location of the UE. This method also includes a determination step S1930, where the determination step S1930 is: Based on a list of cell IDs for multiple Earth-moving cells or cell sections of Earth-moving cells, a notification of a second time when the multiple Earth-moving cells form a registration area, coverage area information and satellite ephemeris data indicating the coverage area of ​​the cell or cell section relative to the satellite position of the satellite generating the cell, and a measurement of the UE's second position (the list of multiple Earth-moving cells and the notification of the second time are included in the registration area notification), or Based on a list of cell IDs, a notification of the time interval in which multiple Earth-moving cells or cell sections form a registration area, and the cell ID of a newly visited cell or cell section that is different from the last cell, including the second location of the UE (the list of cell IDs and the time interval notification are included in the registration area notification), or Based on the second location measurement, the mapping between the geographic area and the tracking area, and a list of one or more tracking areas that make up the registration area (the mapping is read from storage, and the list of one or more tracking areas is included in the registration area notification), At the second location, it is determined whether the UE is located within the registration area.

[0135] Corresponding to the above-mentioned base station, a communication method for a base station is further disclosed. This method, shown in Figure 20, includes step S2010 of receiving a paging request for paging a user equipment (UE), including notification of a registration area. This method further includes step S2020 of determining, Based on a list of cell IDs of a first set of multiple Earth-moving cells or cell sections of Earth-moving cells, a second time notification of when the first set of multiple Earth-moving cells form a registration area, and for each of the first set of multiple Earth-moving cells, coverage area information indicating the coverage area of ​​the cell or cell section relative to the satellite position of the satellite generating the cell, and satellite ephemeris data (the list of the first set of multiple Earth-moving cells and the time notification are included in the registration area notification), or Based on a list of cell IDs and a notification of the time intervals in which the first multiple Earth-moving cells or cell sections form a registration area (the list of cell IDs and the notification of time intervals are included in the registration area notification), or Based on the mapping between geographical areas and tracking areas, and a list of one or more tracking areas that make up the registration area (the mapping is read from storage, and the list of one or more tracking areas is included in the registration area notification), Determine the second set of Earth mobile cells currently mapped to the registration area. This method further includes step S2030, which involves sending a paging message to page the UE within the second set of cells.

[0136] Furthermore, in accordance with the AMF system disclosed above, a communication method for the AMF system is provided. As shown in Figure 21, this method for the AMF system includes step S2110 of receiving a registration request from a user device (UE), where the registration request is • Notification of the UE's first position, or • The cell ID of the last cell visited by the UE, and a timestamp indicating the first time the UE was located within that last cell. Includes.

[0137] This method for the AMF system includes generating a registration area notification that includes the first location of the UE. The registration area notification is • Includes a list of cell IDs for multiple Earth-moving cells or cell sections of Earth-moving cells, and a notification of a second time when the multiple Earth-moving cells form a registration area (the registration area is determined for each of the multiple Earth-moving cells or cell sections based on coverage area information indicating the coverage area of ​​the cell or cell section relative to the satellite position of the satellite generating the cell, and satellite ephemeris data), or, • Includes a list of cell IDs and a notification of the time intervals in which multiple Earth-moving cells or cell sections form a registration area, or • Includes a list of one or more tracking areas that make up the registration area (the list of one or more tracking areas is determined based on the mapping between geographical areas and tracking areas, and the mapping is read from storage).

[0138] Furthermore, this method for AMF includes sending a registration acceptance message that includes notification of the registration area.

[0139] In this disclosure, unless otherwise indicated by the context, any descriptions and examples shall be construed as applicable to UEs, base stations, and AMF systems, respectively, and to both apparatus and methods.

[0140] TAC and stored mapping of geographical areas

[0141] In some embodiments, the mapping between the TAC and the geographic area is predefined as a fixed relationship and installed in the UE's memory. The memory may be a memory device, a SIM (Subscriber Identification Module), internal memory, or other memory device. The UE determines its position, for example, using a GNSS (Global Navigation Satellite System), derives a TAI based on its position information, and sends the derived TAI to the AMF as a notification of its position. The UE then receives a registration acceptance message from the AMF, in which it receives a list of one or more tracking areas (which may be indicated by the TAC) as a notification of its registration area. If the UE needs to determine whether it is still within the registration area at a certain position ("second position") (for example, for periodic updates or when camping or visiting a new cell), the UE circuit 1790 reads the mapping between the tracking area or TAC and the geographic area from storage. Thus, the UE may further include a storage interface for reading the mapping from storage. The UE determines whether it is located within a registration area composed of the TAC(s) in the list, based on a second location (specifically, a TAC formed based on the second location and thereby indicating the second location), a list of received TACs, and a stored mapping.

[0142] For example, in mapping between TACs and geographical areas, one TAC may be assigned to a single country (e.g., TAC1=Germany, TAC2=Austria, TAC3=Switzerland, etc.). For countries with larger areas, multiple TACs can be defined, which may be assigned to states, federal states, etc. Geographical area boundaries may be stored in a storage device such as a UE or SIM, or can be derived from map information such as a digital map stored in a UE or storage device. Thus, a UE can know which area it is located within based on its location measurements.

[0143] Embodiments using stored mappings between TACs and geographical areas offer backward compatibility in that one or more TACs can be used to signal registered areas to UEs as before. However, if the mappings are stored in a storage device such as a UE or SIM, updating the TA definition (mapping from one TAC to a specific region) can be difficult.

[0144] Time cell coverage area

[0145] In some embodiments, the registration area (or tracking area) is defined by a combination of (earth movement) cell coverage areas at a specific time.

[0146] In this case, the cell coverage area may be defined by one of the following pieces of information, which can be included in the coverage area information for each of the multiple Earth-moving cells and thus become available to the UE, as shown in Figures 22 to 24.

[0147] In the first example, as shown in Figure 22, the cell area is defined by the satellite beam direction of each beam forming the cell (as explained with reference to Figures 13 and 14, a cell may consist of one beam or contain multiple beams) and the beam radius or diameter on Earth, such as the radius or diameter of the cell or the beam footprint on Earth. In this case, the cells may overlap.

[0148] In the second example, as shown in Figure 23, the cell area of ​​the Earth-moving cell is defined by polygons that define coverage areas that do not overlap. For example, the cell area is defined by the vertices of a non-overlapping shape such as a rectangle or hexagon.

[0149] For example, a polygon may be represented using a reference point (e.g., an angle or center) that can be a relative position to the current satellite position available from ephemeris data, along with the side lengths of the polygon or another notification of the polygon's size. In another example, a polygon may be represented using the coordinates of all the angles of the polygon relative to the satellite position.

[0150] In the third example shown in Figure 24, a cell may be defined by its center and the in-coverage distance from that center (e.g., the in-coverage radius). In this example, the signaling may be the same as in the first example.

[0151] The above definitions of coverage area information under the first to third options can be provided relative to the satellite position, for example, the satellite position of the satellite(s) generating the satellite beam(s), which changes over time and can be derived from ephemeris data for a given point in time. As the satellite moves over time, the coverage area, for example, its size, may also change over time. For example, the size of the satellite beam area may be adjusted to match the UE density or population density of the area covered by the satellite beam. Thus, if the satellite is moving over a more densely populated area of ​​Earth, the coverage area, such as the beam footprint or ground cell / beam area, may be reduced to accommodate the increased demand caused by more UEs that need to be serviced by providing smaller cells.

[0152] The tracking area or registration area is defined by a combination of cell areas associated with a timestamp, as shown in Figure 25 (for example, TA1 = {cell 1, cell 2, cell 3, cell 4, t = 13:01}, and TA2 = {cell 5, cell 6, cell 7, cell 8, t = 13:01}).

[0153] In the case of defining the cell coverage area of ​​moving cells according to the above examples in Figures 22-24 associated with a given timestamp, the user device can use the cell coverage area information, timestamp, and satellite ephemeris data to calculate the area on Earth covered by these cells at the indicated time. The registered area and / or tracking area can then be determined as the area covered by multiple cells at a particular time. Thus, the tracking area and / or registered area can be thought of as being defined by “frozen cells” that covered or will cover the registered area at the indicated time.

[0154] For example, the UE receives coverage area information within the system information. For instance, cell coverage areas are signaled from the gNB to the UE via broadcasted RRC signaling, such as SIB. In addition to cell coverage areas, the UE may further receive satellite ephemeris data or a portion of ephemeris data in the system information, which the UE may then use to calculate the satellite's motion relative to the Earth's surface (possibly with further portions of ephemeris data that may be pre-stored in a storage device).

[0155] Registration areas are signaled from the AMF to the UE via NAS signaling, such as registration acceptance messages or configuration update command messages shown in Figures 6 and 7. In this case, it is sufficient for the UE to signal only the TAs to which it is registered. These TAs can be specifically signaled by signaling "frozen cells," i.e., a list of cell IDs and a timestamp indicating the time when the cells in that list form a registration area. For example, registration area = {cell 1, cell 2, cell 3, cell 4, cell 5, cell 6, cell 7, cell 8, t=13:01}, which corresponds to TAC1 and TAC2 in Figure 25. These cell IDs can be signaled instead of TA codes, and TA codes are not required for the UE to determine the registration area. Nevertheless, the concept of tracking areas can still be used on the AMF or base station side. For example, the AMF may contain multiple cells to form a registration area assigned to the UE.

[0156] Therefore, the UE knows the mapping between the registered area and geographical locations. Based on this, the UE can determine whether or not it has left the registered area from its own location information, such as GNSS position measurements.

[0157] For example, to determine whether a UE is still within a registration area, the UE may test whether it is within each cell coverage area of ​​the "frozen cells" that make up the registration area at a given time, for example, by comparing the distance from the UE to the cell center with the cell radius. If 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 registration area and can stop the calculation. Alternatively, based on multiple cell coverage areas, the UE may calculate the extent or boundaries of the registration area and determine whether the UE is located within these boundaries for the entire registration area.

[0158] Cell coverage area information can also be pre-configured in both the AMF system and the gNB during the cell planning phase, or alternatively, signaled from the gNB to the AMF via NGAP signaling, such as NG setup request messages or RAN configuration update messages (see Figures 8 and 9). Furthermore, mappings between cells and gNBs can be pre-configured in the AMF. The UE reports to the AMF, via a registration request message, the cell ID of the last visited cell with a timestamp, or alternatively, reports a notification of the UE's location.

[0159] Therefore, AMF knows which gNB(s) are covering the registration area at any given time and can determine which gNB(s) should deliver the paging message.

[0160] Furthermore, the definitions of tracking and registration areas in the form of cell IDs and timestamps corresponding to "frozen cells" are signaled from the AMF to the gNB, for example, in paging messages. Thus, the gNB can know which cells(s) cover the registration area and decide which cells should broadcast paging.

[0161] A possible example of the registration and paging call flow is shown in Figure 26. As illustrated, the gNB sends an SIB to the UE containing cell coverage information, including a notification of the cell coverage area relative to the satellite position. The SIB may further include a notification of satellite ephemeris data unless the ephemeris data is fully stored on the UE side. In addition, the gNB may send cell coverage area information included in the NG setup request message to the AMF (for example, if cell coverage information is not similarly pre-configured in the AMF).

[0162] At the time t of initial registration, the UE sends a registration request message to the AMF that includes the UE's location information or the cell ID of the last visited cell along with a timestamp. In response, the AMF sends a registration acceptance message to the UE as a notification of the registration area, which includes a list of cell IDs and a timestamp of the time when the cells indicated by the list form the registration area. As shown in Figure 26, the registration request and registration acceptance may be forwarded by the gNB.

[0163] At time t+1, while the UE is idle, the AMF receives downlink data for the UE. The AMF system then determines which gNBs are currently mapped to the registration area and which serve the cells currently mapped to the registration area. To these gNBs, the AMF system sends a paging message (or paging request message) containing a list of cells and the timestamps of those cells that form the registration area. Using the list, timestamps, and ephemeris data held by the gNB, the gNB determines which of the cells it serves are currently included in the registration area and performs paging of the UE across these cells included in the registration area.

[0164] Paging is initiated by the AMF when the UE is in RRC idle mode. Thus, the AMF sends a paging message to the base station(s), and the base station broadcasts the paging message to the cells of the registration area to page the UE. In this disclosure, the terms “paging request” or “paging request message” are used for messages from the AMF to the base station that include a notification from the registration area and may include a paging message for page the UE.

[0165] At time t+2, the UE may detect, based on its position measurement, that its location is outside the registration area. The UE then sends a new registration request including its current location and receives a registration acceptance message containing a list of new cell IDs and timestamps indicating when these cells form the UE's new registration area. The UE then replaces the previous registration area with the new one.

[0166] If cell coverage area information is included in the SIB along with ephemeris data, this data can make it easier for the UE to perform cell selection without measuring radio signal strength, because otherwise, radio signal strength measurements may be frequently performed due to cell movement. Therefore, cell coverage area information can be used by the UE for cell selection and re-selection, and to determine whether the UE is within a registered area.

[0167] Furthermore, if a cell coverage area is already available via SIB, only a limited amount of signaling overhead (cell ID + timestamp) is required to indicate the registered area based on the cell coverage area information.

[0168] Each cell has its own timing.

[0169] In some embodiments, a registration area or tracking area is defined by listing all cells associated with each timing (or time interval) in which a cell covers a given geographical location or area on Earth. As a notification of a registration area, the UE is provided with a list of cell IDs of Earth-moving cells and a notification of the time intervals in which the Earth-moving cells form a registration area.

[0170] Furthermore, the registration area notification included in the registration acceptance message from AMF may include a list of multiple cell IDs of Earth-moving cells (or cell sections), and for each list of the multiple cell IDs, a notification of multiple time intervals indicating when the Earth-moving cells (or cell sections) indicated by that list of cell IDs form a registration area.

[0171] Therefore, by notifying the UE of cells within the registration area for multiple time intervals, it becomes unnecessary to signal the registration area every time the cells that make up the registration area change.

[0172] Figure 27 shows an example of how two tracking areas TA1 and TA2 change within two time intervals, 13:01-13:10 and 13:11-13:20, as follows (as in the example in Figure 25, this example is illustrative and the disclosure is not limited to any particular length of time interval or the number of cell IDs within a registration area or tracking area). ·TA1={13:01~13:10 Cell 1, Cell 2, Cell 3; 13:11~13:20 Cell 2, Cell 3, Cell 4; ...} ·TA2={13:01~13:10 Cell 4, Cell 5, Cell 6; 13:11~13:20 Cells 5, 6, and 7; ...}

[0173] As can be seen from Figure 27, the set of cells included in the TA remains the same for a certain period or time interval (10 minutes in the example above). Therefore, furthermore, because the cells are constantly moving, the resulting TA (and thus the registration area) is also affected.

[0174] In embodiments where one or more lists of such cell IDs and corresponding time intervals are signaled to the UE as registration area notifications, tracking area codes are not required on the UE side. Nevertheless, tracking areas may be used on the AMF side to determine which registration areas should be assigned to the UE. This disclosure is not limited to any specific method by which tracking areas are determined on the AMF side.

[0175] For example, considering the example in Figure 27, the UE may be assigned registration areas {TA1;TA2}.

[0176] Therefore, the UE may show registration areas in two subsequent time intervals as follows: RA={13:01~13:10 Cell 1, Cell 2, Cell 3, Cell 4, Cell 5, Cell 6; 13:11~13:20 Cell 2, Cell 3, Cell 4, Cell 5, Cell 6, Cell 7

[0177] The registration area is signaled from the AMF to the UE via NAS signaling, for example, a registration acceptance message or a configuration update command message, in the form of a set of cells (corresponding to a list of multiple cell IDs) associated with timing (for example, each time interval in which one of the set of cells forms a registration area).

[0178] It is not necessary to notify the UE of the coverage area of ​​each cell. Legacy cell (re)selection based on radio signal strength can be reused. As a result, when the UE performs legacy cell (re)selection based on radio signal strength, the UE can determine whether it has left the registration area without determining its own location, based on the cell ID of the newly visited or camped cell and the timing of the visit to that cell.

[0179] Furthermore, cell coverage area information can be pre-configured in the AMF (and possibly gNB) during the cell planning phase, for example, based on an estimate of the cell coverage of a mobile Earth cell. Mapping between cells and gNBs can also be pre-configured in the AMF. Therefore, the AMF knows which gNB(s) cover the registration area at any given time, and can determine which gNB(s) should receive the paging message.

[0180] Furthermore, in the registration request message, the UE signals the AMF with the cell ID of the last cell it visited and the timestamp in which the UE was located within that cell (for example, the timestamp of the signal strength measurement).

[0181] Additionally, registration areas (and / or tracking areas) are signaled to the gNB, for example, in a paging message (or a paging request containing a paging message), in the form of a set of cells (corresponding to a list of multiple cell IDs) associated with timing (for example, the time interval at which one of the set of cells forms a registration area). As a result, the gNB can know which cells(s) cover the registration area and decide which cells to broadcast paging to.

[0182] An exemplary registration and paging call flow is shown in Figure 28. At time t, for example, if initial registration of the UE is performed, the UE sends a registration request to the AMF indicating the last visited cell with a timestamp. The UE then receives a registration acceptance message from the AMF, which includes a set of multiple cells (for example, a list of multiple cell IDs) and an associated timing which is when one set of cells forms a registration area, as a notification of the registration area.

[0183] At time t+1, if the UE is to be paged by the core network, the AMF, having received DL data for the UE, determines the gNB(s) currently mapped to the registration area and sends a paging message (or a paging request message containing a paging message) to these gNBs, which contains a set of multiple cells associated with the timing as the registration area. In principle, it is sufficient for the gNBs to receive only the IDs of the cells they serve. The gNBs determine the cells currently mapped to the registration area and perform paging of the UE.

[0184] If, at time t+2, the UE camps in a new cell outside the registration area, a registration request containing the cell ID of the newly visited cell and a registration acceptance message containing a new set of cells indicating the new registration area are exchanged between the UE and the AMF in the same manner as during the initial registration at time t.

[0185] If the registration area is presented to the UE as a set of cell IDs and the associated timings that form the registration area, the UE does not need to be able to determine its own location and can reuse legacy cell selection based on radio strength. Nevertheless, instead of the cell ID and timestamp of the last visited cell, the UE may instead send location information in the registration request.

[0186] Furthermore, the TAC does not need to be broadcast by the moving cell. Therefore, problems related to TAC broadcasting do not necessarily occur. Such problems may include TAC fluctuations due to "hard switches" or overhead due to soft switches.

[0187] Geographic zones and radio signal coverage

[0188] In some embodiments, the TA and / or registered area RA are defined by a timing-associated cell area or “restricted cell area” (corresponding to a cell section), where the “restricted cell area” is defined by the intersection of a geographic zone and radio signal coverage.

[0189] Geographic zones can be pre-installed on the UE (for example, stored in a SIM or other memory device) and pre-defined within the network (gNB and core network). These geographic zones can be used, for example, to define the borders of authorization areas.

[0190] For example, a satellite beam may broadcast multiple cell IDs (cell IDs may correspond not only to cells but also to cell sections or “restricted cell areas”) associated with different cells that may belong to different countries or licensed areas. In this case, if cell (re)selection is performed using signal strength, the UE may receive the same signal strength from multiple cells or cell sections because they are generated by the same satellite beam. However, multiple cells or sections corresponding to “restricted cell areas” may be associated with different licensed areas. For example, a satellite beam travels across the globe along the border of two countries and broadcasts two cell IDs for each country. In this disclosure, “restricted cell ID,” each which may have its own cell ID, refers to a cell section of a cell in one of a predefined geographic area. The UE then selects the cell with the strongest radio strength permitted (or licensed) at a given location.

[0191] For example, if the UE determines that it is not located within a registration area (for example, by location measurement, or by comparing the cell ID (or signal strength from multiple cell IDs) of a newly camped or visited cell with a list of cell IDs that define the previous registration area over a given time interval), the UE performs a signal strength measurement for cell (re)selection and may receive identical or similar signal strengths from multiple cells, which are therefore candidates for the newly visited cell.

[0192] The UE can then determine the geographic area in which it is located from among stored or pre-installed geographic areas, based on the location measurement and the definition of a geographic area that can be read from storage or memory.

[0193] Next, the UE selects one candidate within the geographical area where the UE is located as the new cell or cell section to visit. This selection is based on the association between each cell ID among the multiple candidates and one of the stored geographical areas.

[0194] This association between cell IDs and geographical areas (for example, a mapping between cell IDs and geographical zone information) can be signaled to the UE on a per-cell basis from the gNB within the system information (e.g., SIB) received by the UE.

[0195] Furthermore, if, for example, the list of cell IDs indicated by the AMF extends beyond a restricted geographic area, the installed or stored geographic area may be used by the UE to determine which cells, either from the list of cell IDs or from the list of multiple cell IDs, reside within that geographic area. The UE circuit 1790 may then determine the registration area formed by the cell or cell section from the list(s) of cell IDs associated with the geographic area where the UE is located.

[0196] Figure 29 shows an example of multiple cell sections or “restricted cell areas” divided into different geographical areas or zones. It can be assumed that one satellite beam transmits multiple (e.g., two or more) cell IDs. For example, beam 1 covers both cell 1 and cell 2. Since both cells or restricted cell areas reside within the same radio coverage, the UE detects similar (e.g., substantially identical) radio signal strengths from both cells associated with the same radio satellite beam. Based on location information regarding whether the UE is located in zone A or zone B, the UE may select restricted cell area (RCA) 1 or RCA2, where RCA1 = common area {cell 1, zone A} and RCA2 = common area {cell 2, zone B}. Different tracking or registration areas may be indicated by signaling a list of multiple cell IDs (or RCA IDs or cell section IDs) with associated timing or time intervals. TA1 (or RA1) = {13:01~13:10 RCA1, RCA3, RCA5; 13:11~13:20 RCA3, RCA5, RCA7}; TA2 (or RA2) = {13:01~13:10 RCA2, RCA4, RCA6; 13:11~13:20 RCA4, RCA6, RCA8}

[0197] As described above, the definition of a geographic zone or area may be stored or installed in the UE or a memory device. Furthermore, the association between a cell ID (or RCA ID) and a geographic zone may be broadcast by the gNB, for example, via the SIB. A registration area in the form of a set of multiple cells with associated timings is signaled from the AMF to the UE via NAS signaling (e.g., a registration acceptance message), similar to the above description of the embodiment titled "Cells with their respective timings".

[0198] As a result, the UE can perform cell (re)selection based on both location information and signal strength, and determine whether the UE has left the registered area based on the camping cell ID and timing.

[0199] The manner in which the AMF system and gNB are signaled may be similar to the description above in the section "Cells with their Own Timings." Cell coverage area information (including mapping to the gNB) may be set or pre-configured in the AMF (and gNB) during the cell planning phase. The UE signals to the AMF in a registration request message the last visited cell with a timestamp, or signals location information. The definition of the TA and / or registration area is also signaled to the gNB in ​​the form of a set of multiple cells with associated timings (a list of cell IDs / RCA IDs), for example in a paging message, or in a paging request message, which also includes paging messages sent to the UE.

[0200] As a result, the AMF knows which gNBs cover the registration area at any given time and can determine which gNBs should receive paging messages (or paging request messages). The gNBs also know which cells cover the registration area and can determine which cells should broadcast paging.

[0201] The registration and paging call flow between the UE, gNB, and AMF is shown in Figure 30. As described above, the UE receives the SIB transmitted from the gNB, which includes a mapping between the cell ID (RCA ID) and zone information. Furthermore, although it is shown that the UE transmits location information in the registration request (steps 1 and 6), the UE may also transmit the cell ID and associated timing. Also, at timing t+2, the UE camps in a new cell outside the registration area, which is selected or determined based on radio strength and UE location (for example, to determine which zone or geographic area the UE is located in). The further flow shown in Figure 30 is similar to the description above of the flow shown in Figure 28.

[0202] As described in this section, cell accessibility is controlled using additional location information in addition to received signal strength. When multiple cells or cell sections are transmitted by the same satellite, controlling cell accessibility using this additional location information can facilitate a reduction in the number of cells in the registration area and reduce paging overhead.

[0203] As described above, a UE may perform cell (re)selection, for example, selecting new cells to visit inside or outside its registered area, based on either location information (e.g., location measurements such as GNSS) or signal strength measurements. For example, if location information is used to determine whether the UE is still within its registered area, cell selection may also be location-based, which can facilitate a reduction in signal strength measurements. On the other hand, determining whether the UE is within its registered area using signal strength may be practical for UEs that are unable to position themselves or whose positioning function is turned off.

[0204] Furthermore, as shown in Figures 26, 28, and 30, if the circuit determines that the UE is not located within the registration area, the circuit sends a registration request that includes either a notification of the UE's location or at least one of the following: the cell ID of the newly visited cell and a timestamp indicating the time when the UE was located within the newly visited cell (for example, when the signal strength was measured).

[0205] On the other hand, if the UE is within the registration area and DL data for the UE is available, the UE will receive paging (for example, one or both of the paging DCI and paging messages) sent by gNB (or multiple gNBs) within the registration area.

[0206] One or more base stations (e.g., gNBs) that perform paging for the UE are determined by the AMF system. Specifically, in some embodiments, the AMF determines the base stations currently mapped to the registration area (which has already been shown to the UE via registration acceptance) and sends a paging request message to one or more base stations. The paging request message is: • A list of cell IDs for multiple Earth-moving cells or cell sections, and a notification of a second time zone, or • A list of cell IDs, and notification of the time intervals in which multiple Earth-moving cells or cell sections form a registered area, or • A list of tracking areas that make up the registration area. Includes.

[0207] For example, a paging request message may contain further paging messages.

[0208] As described above, embodiments of this disclosure show that it is not necessary to broadcast a TA code (TAC: TA code) within the cell system information in order to indicate the registration area to the UE. Therefore, problems related to moving tracking areas, such as those associated with "hard switches" and "soft switches," can be mitigated or avoided. Specifically, in embodiments described with reference to Figures 22 to 30, a TA code may be unnecessary at all.

[0209] Furthermore, each of the embodiments described above, shown in Figures 22 to 30, includes timing information for defining tracking and registration areas (for example, the time at which a “frozen” cell is defined, or the time interval at which each cell covers the registration area). Such timing information allows cell movement to be recognized by the gNB and core network in a predictable manner. In addition, in the embodiments described in the section titled “Time Cell Coverage Areas”, ephemeris data is also available to the UE, which may use this to determine the registration area and, in some cases, to (re)select cells.

[0210] As described above, the examples and embodiments of this disclosure were presented using registration area management for an RRC 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 device tracking at the RAN level. Updates to the RAN notification area are managed by RRC RAN notification area updates sent from the UE to the gNB. Since changes in the tracking area suggest changes in the RNA, an RRC RAN notification area update is implicitly performed each time the UE performs a registration update, as described above.

[0211] This disclosure can be implemented by software, hardware, or software in conjunction with hardware. Each functional block used in the description of each embodiment above can be partially or completely implemented by a large-scale integrated circuit (LSI), such as an integrated circuit (IC), and each process described in each embodiment can be partially or completely controlled by the same LSI or combination of LSIs. An LSI may be formed individually as a chip, or a single chip may be formed to include some or all of the functional blocks. An LSI may include data inputs and outputs coupled thereto. In this specification, LSIs may be called ICs, system LSIs, super LSIs, and ultra LSIs depending on their degree of integration. However, the techniques for implementing integrated circuits are not limited to LSIs and can be implemented using dedicated circuits, general-purpose processors, or dedicated processors. Alternatively, a field-programmable gate array (FPGA) that can be programmed after the LSI is manufactured, or a reconfigurable processor that can reconfigure the connections and settings of circuit cells arranged within the LSI, may be used. This disclosure can be implemented as digital or analog processing. If future integrated circuit technology replaces LSIs as a result of advances in semiconductor technology or other derivative technologies, functional blocks can be integrated using future integrated circuit technology. Biotechnology can also be applied.

[0212] This disclosure can be implemented by any type of device, apparatus, or system having communication capabilities, referred to as a communication apparatus.

[0213] A communication device may include a transceiver and a processing / control circuit. The transceiver may include and / or function as both a receiver and a transmitter. A transceiver acting as both a transmitter and a receiver may include an RF (radio frequency) module, such as an amplifier, an RF modulator / demodulator, and one or more antennas.

[0214] Some non-exclusive 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, telehealth / telemedicine (remote health and medicine) devices, and vehicles that provide communication capabilities (e.g., automobiles, airplanes, ships), as well as various combinations thereof.

[0215] Communication devices are not limited to portable or mobile devices, but may include any type of non-portable or fixed device, device, or system, such as smart home devices (e.g., appliances, lighting, smart meters, control panels), vending machines, and any other "things" in the "Internet of Things (IoT)" network.

[0216] Communication can include, for example, data exchange via cellular systems, wireless LAN systems, satellite systems, and various combinations thereof.

[0217] A 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, a communication device may include a controller or sensor that generates control signals or data signals used by the communication device that performs the communication functions of the communication device.

[0218] Communication equipment may also include infrastructure facilities such as base stations, access points, and any other equipment, devices, or systems that communicate with or control equipment such as those described in the non-limiting examples above.

[0219] In summary, in the first embodiment, a user equipment (UE) transmits a registration request during operation, and the registration request includes · notification of the first position of the UE, or · the cell ID of the last cell visited by the UE and a timestamp indicating the first time when the UE was located within the last cell, receives a registration acceptance message including notification of a registration area, the registration area including the first position of the UE, and a transceiver that, during operation, · based on a list of cell IDs of a plurality of terrestrial cells or cell sections of the terrestrial cells, notification of a second time when the plurality of terrestrial cells form the registration area, coverage area information indicating a coverage area of the cell or cell section relative to the satellite position of the satellite generating the cell for each of the plurality of terrestrial cells, ephemeris data of the satellite, and a measurement value of the second position of the UE, wherein the list of the plurality of terrestrial cells and the notification of the second time are included in the notification of the registration area, or · based on a list of the cell IDs, notification of a time interval during which the plurality of terrestrial cells or cell sections form the registration area, and including the second position of the UE, a cell ID of a newly visited cell or cell section different from the last cell, wherein the list of the cell IDs and the notification of the time interval are included in the notification of the registration area, or · based on the measurement value of the second position, a mapping between a geographical area and a tracking area, and a list of one or more tracking areas forming the registration area, wherein the mapping is read from storage and the list of the one or more tracking areas is included in the notification of the registration area, A user equipment is provided that includes a circuit that determines whether the UE is located within the registration area at the second position.

[0220] In the second embodiment, in addition to the first embodiment, when operating, the transceiver receives the coverage area information within the system information.

[0221] In the third embodiment, in addition to the first or second embodiment, for each of the plurality of terrestrial cells, the coverage area information · includes the satellite beam direction of each beam forming the cell, and the radius or diameter of the coverage area, or · includes a polygon that defines the coverage areas so as not to overlap, or · includes the center and radius of the coverage area. is included.

[0222] In the fourth embodiment, in addition to the first embodiment, the notification of the registration area includes a list of cell IDs of terrestrial cells or cell sections of terrestrial cells including the list of cell IDs, and for each of the lists of the plurality of cell IDs, a plurality of notifications of time intervals including the time intervals respectively indicating the time intervals during which the terrestrial cells or cell sections respectively indicated by the list of cell IDs form the registration area.

[0223] In the fifth embodiment, in addition to the first or fourth embodiment, when the circuit determines that the UE is not located within the registration area at the second position, and the received signal strengths of a plurality of candidates of the newly visited cell or cell section are substantially the same, when operating, the circuit determines the geographical area in which the UE is located from the geographical areas based on the measurement value at the second position and the definition of the geographical area read from the storage, and selects, as the newly visited cell or cell section, a candidate included in the geographical area in which the UE is located based on the association between each cell ID of the plurality of candidates included in the system information and one of the geographical areas.

[0224] In the sixth embodiment, in addition to any of the first to fifth embodiments, the circuit selects the new cell to visit based on the second position during operation.

[0225] In the seventh embodiment, in addition to the first, fourth, or fifth embodiments, the circuit selects the newly visited cell based on a signal strength measurement during operation.

[0226] In the eighth embodiment, in addition to any of the first to seventh embodiments, the transceiver receives a paging message within the registration area during operation.

[0227] In the ninth embodiment, in addition to any of the first to eighth embodiments, if the circuit determines that the UE is not located within the registration area at the second position, the transceiver transmits a second registration request during operation, and the second registration request is • Notification of the second location of the UE, or • The cell ID of the newly visited cell, and a timestamp indicating a third time when the UE was located within the newly visited cell. It includes at least one of the following.

[0228] In the tenth embodiment, a base station having an interface that, when operating, receives a paging request message for paging user equipment (UE), including notification of a registered area, and when operating, Based on a list of cell IDs of a first plurality of Earth-moving cells or cell sections of said Earth-moving cells, a notification of a second time when said the first plurality of Earth-moving cells form said registration area, and for each of said first plurality of Earth-moving cells, coverage area information indicating the coverage area of ​​said cell or cell section relative to the satellite position of the satellite that generates said cell, and ephemeris data of said satellite, wherein said list of said first plurality of Earth-moving cells and said notification of said time are included in said notification of said registration area, or Based on the list of cell IDs and the notification of the time intervals in which the first plurality of Earth mobile cells or cell sections form the registration area, where the list of cell IDs and the notification of the time intervals are included in the notification of the registration area, Based on a mapping between geographical areas and tracking areas, and a list of one or more tracking areas that form the registration area, where the mapping is read from storage, and the list of one or more tracking areas is included in the notification for the registration area, A base station is provided, comprising: a circuit that determines a second plurality of Earth mobile cells currently mapped to the registration area; and a transceiver that, in operation, transmits paging messages for paging the UE within the second plurality of cells.

[0229] In the eleventh embodiment, an access and mobility management function (AMF) system is provided, which, in operation, has an interface for receiving registration requests from user equipment (UE), wherein the registration request is: • Notification of the first location of the UE, or • The cell ID of the last cell visited by the UE, and a timestamp indicating the first time the UE was located within that last cell. The interface, and a circuit that, in operation, generates a notification of a registration area including the first location of the UE, wherein the notification of the registration area is • A list of cell IDs of multiple Earth-moving cells or cell sections of said Earth-moving cells, and a notification of a second time in which said Earth-moving cells form the registration area, wherein the registration area is determined for each of the multiple Earth-moving cells or cell sections based on coverage area information indicating the coverage area of ​​said cell or cell section relative to the satellite position of the satellite generating said cell, and the satellite's ephemeris data, or The system includes a list of cell IDs and a notification of the time intervals in which the multiple Earth-moving cells or cell sections form the registration area, or - Includes a list of one or more tracking areas that form the registration area, wherein the list of one or more tracking areas is determined based on a mapping between geographical areas and tracking areas, and the mapping is read from storage. An AMF system is provided comprising the circuit and the interface, wherein, in operation, transmits a registration acceptance message including the notification of the registration area.

[0230] In the twelfth embodiment, in addition to the eleventh embodiment, the circuit, in operation, determines one or more base stations currently mapped to the registration area, the interface, in operation, transmits a paging request message to one or more base stations, and the paging request message is • A list of the cell IDs of the multiple Earth-moving cells or cell sections and the notification of the second time, or • A list of cell IDs, and a notification of the time intervals in which the multiple Earth-moving cells or cell sections form the registration area, or • A list of the tracking areas that form the registration area, Includes.

[0231] In the 13th embodiment, a communication method for user equipment (UE), comprising the step of transmitting a registration request, wherein the registration request is • Notification of the first location of the UE, or • The cell ID of the last cell visited by the UE, and a timestamp indicating the first time the UE was located within that last cell. A step comprising at least one of the following: receiving a registration acceptance message including a registration area notification, wherein the registration area includes the first location of the UE; and determining Based on a list of cell IDs of multiple Earth-moving cells or cell sections of said Earth-moving cells, a notification of a second time in which the multiple Earth-moving cells form the registration area, and for each of the multiple Earth-moving cells, coverage area information and ephemeris data of the satellite indicating the coverage area of ​​the cell or cell section relative to the satellite position of the satellite generating the cell, and a measurement of the second position of the UE, wherein the list of multiple Earth-moving cells and the notification of the second time are included in the notification of the registration area, Based on the list of cell IDs, the notification of the time intervals in which the plurality of Earth-moving cells or cell sections form the registration area, and the cell ID of a newly visited cell or cell section, which includes the second location of the UE and is different from the last cell, where the list of cell IDs and the notification of the time intervals are included in the notification of the registration area, or Based on the measured values ​​of the second location, the mapping between the geographic area and the tracking area, and a list of one or more tracking areas forming the registration area, where the mapping is read from storage, and the list of one or more tracking areas is included in the notification of the registration area, A communication method is provided which includes the step of determining whether the UE is located within the registration area at the second location.

[0232] A 14th embodiment is a communication method for a base station, comprising the steps of receiving a paging request message for paging user equipment (UE), including notification of a registered area, and determining · A list of cell IDs of the first plurality of terrestrial cells or cell sections of the terrestrial cell, a notification of a second time at which the first plurality of terrestrial cells form the registration area, and for each of the first plurality of terrestrial cells, based on coverage area information indicating a coverage area of the cell or cell section relative to a satellite position of a satellite that generates the cell and ephemeris data of the satellite, wherein the list of the first plurality of terrestrial cells and the notification of the time are included in the notification of the registration area, or, · Based on the list of the cell IDs and a notification of a time interval during which the first plurality of terrestrial cells or cell sections form the registration area, wherein the list of the cell IDs and the notification of the time interval are included in the notification of the registration area, or, · Based on a mapping between a geographical area and a tracking area and a list of one or more tracking areas that form the registration area, wherein the mapping is read from storage and the list of the one or more tracking areas is included in the notification of the registration area, A step of determining a second plurality of terrestrial cells currently mapped to the registration area, and a step of transmitting a paging message for paging the UE within the second plurality of cells are provided.

[0233] In a 15th embodiment, a communication method for an access mobility function (AMF) system, the method comprising receiving a registration request of a user equipment (UE), wherein the registration request · A notification of a first position of the UE, or, · A cell ID of a last cell visited by the UE and a timestamp indicating a first time when the UE was located within the last cell, generating a notification of a registration area including the first position of the UE, wherein the notification of the registration area • A list of cell IDs of multiple Earth-moving cells or cell sections of said Earth-moving cells, and a notification of a second time in which said Earth-moving cells form the registration area, wherein the registration area is determined for each of the multiple Earth-moving cells or cell sections based on coverage area information indicating the coverage area of ​​said cell or cell section relative to the satellite position of the satellite generating said cell, and the satellite's ephemeris data, or The system includes a list of cell IDs and a notification of the time intervals in which the multiple Earth-moving cells or cell sections form the registration area, or - Includes a list of one or more tracking areas that form the registration area, wherein the list of one or more tracking areas is determined based on a mapping between geographical areas and tracking areas, and the mapping is read from storage. A communication method is provided, which includes the step of sending a registration acceptance message including the notification of the registration area.

[0234] It should be noted that the second to ninth embodiments are applicable in accordance with the base station of the tenth embodiment and the AMF system of the eleventh embodiment, and the twelfth embodiment is applicable in accordance with the base station of the tenth embodiment. Furthermore, the steps performed by the circuit during operation, the steps performed by the transceiver during operation, and the steps performed by the interface during operation, as mentioned in the above embodiments of the UE, base station, and AMF, correspond to their respective methods.

[0235] Furthermore, a non-temporary medium is provided for storing program instructions that cause a processing circuit, such as a general-purpose processor, to execute all the steps of the above-described embodiment when executed by the processing circuit.

[0236] Furthermore, the present invention provides an integrated circuit 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 embodiments of the above method.

[0237] In summary, the system provides a user equipment (UE), a base station, an AMF (Access and Mobility Management Function) system, and a corresponding method. The UE determines, based on a combination of signal strength measurements or location and either a list of cell IDs of Earth mobile cells and a stored mapping between geographical areas and tracking areas, whether the UE is located in a registration area indicated to the UE by the AMF and paged by the base station.

Claims

1. It is a base station, A transceiver that receives a registration request and transmits a registration acceptance message including a list of one or more tracking areas forming a registration area, wherein the registration request includes notification of a first location of a user device (UE), and the list of one or more tracking areas includes notification of the first location of the UE, A circuit for generating the registration acceptance message, which includes a list of one or more tracking areas, wherein the tracking areas correspond to the cell IDs of a plurality of Earth movement cells associated with time intervals forming the registration areas. A base station equipped with the necessary equipment.

2. The base station according to claim 1, wherein the registration request includes the cell ID of the last cell visited by the UE, and a timestamp indicating a first time when the UE was located in the last cell.

3. The base station according to claim 2, wherein the transceiver transmits coverage area information within the system information.

4. The coverage area information is provided for each of the plurality of Earth mobile cells, - The satellite beam direction of each beam forming the cell, and the radius or diameter of the coverage area, or - A polygon that defines the coverage areas so that they do not overlap, or - The center and radius of the coverage area, The base station according to claim 3, including the above.

5. The aforementioned notification for the registration area is A list of multiple cell IDs of a global mobile cell or a cell section of a global mobile cell, including the aforementioned list of cell IDs, For each of the lists of the plurality of cell IDs, a plurality of notifications of time intervals including the time interval, each indicating the time interval in which the Earth mobile cell or cell section indicated by the list of cell IDs forms the registration area, The base station according to claim 2, including the above.

6. The base station according to claim 2, wherein the transceiver transmits paging messages within the registered area.

7. A communication method for a base station, A step of receiving a registration request, wherein the registration request includes notification of a first location of the user equipment (UE), A step of sending a registration acceptance message which includes a list of one or more tracking areas that form a registration area, wherein the one or more tracking areas include notification of the first location of the UE, A step of generating the registration acceptance message which includes a list of one or more tracking areas, wherein the tracking areas correspond to cell IDs of a plurality of Earth movement cells associated with time intervals that form the registration areas, A communication method that includes this.

8. An integrated circuit that controls the processing of a base station, wherein the processing is A step of receiving a registration request, wherein the registration request includes notification of a first location of the user equipment (UE), A step of sending a registration acceptance message which includes a list of one or more tracking areas that form a registration area, wherein the one or more tracking areas include notification of the first location of the UE, A step of generating the registration acceptance message which includes a list of one or more tracking areas, wherein the tracking areas correspond to cell IDs of a plurality of Earth movement cells associated with time intervals that form the registration areas, An integrated circuit, including

Images