Non-terrestrial network satellite group establishment

Abstract

The invention relates to non-terrestrial network satellite group establishment. Systems, methods, apparatuses, and computer program products are provided for establishing a group of non-terrestrial network satellites in which a satellite initiating primary authentication moves out of coverage and a new satellite begins to serve user equipment during primary authentication and access and non-access stratum security context establishment. A method may include establishing, by a first satellite, a connection with at least one satellite of a plurality of satellites; generating, by the first satellite, a selective satellite group comprising at least one satellite of the plurality of satellites, the plurality of satellites comprising the first satellite; and sending, by the first satellite, an indication of the plurality of satellites of the selective group of satellites to an access and mobility management function.

Description

Technical Field

[0001] Some example embodiments may generally relate to mobile or wireless telecommunication technologies and systems, such as 3rd Generation Partnership Project (3GPP) Long Term Evolution (LTE), 5th Generation (5G) Radio Access Technology (RAT), New Radio (NR) access technology, 6th Generation (6G), and / or other communication systems. For example, certain example embodiments may relate to systems and / or methods for establishing a non-terrestrial network satellite group, wherein a satellite initiating a primary authentication moves out of coverage and a new satellite begins serving a user device during the primary authentication and access and non-access stratum security context establishment. Background Art

[0002] Examples of mobile or wireless telecommunication technologies and systems may include radio frequency (RF) 5G RAT, universal mobile telecommunication system (UMTS) terrestrial radio access network (UTRAN), LTE evolved UTRAN (E-UTRAN), advanced LTE (LTE-A), LTE-APro, NR access technology, and / or MulteFire Alliance. 5G wireless system refers to the next generation (NG) radio system and network architecture. 5G systems are typically built on 5G NR, but 5G (or NG) networks can also be built on E-UTRA radio. NR is expected to support service categories such as enhanced mobile broadband (eMBB), ultra-reliable low latency communications (URLLC), and massive machine type communications (mMTC). NR is expected to provide extreme broadband, ultra-robust, low latency connections, and large-scale networking to support the Internet of Things (IoT). Next generation radio access network (NG-RAN) represents a 5G radio access network (RAN), which can provide radio access for NR, LTE, and LTE-A. Note that in 5G, a node that provides radio access functionality to user equipment (e.g., similar to a Node B in UTRAN or an evolved Node B (eNB) in LTE) may be referred to as a next-generation Node B (gNB) when built on an NR radio, and may be referred to as a next-generation eNB (NG-eNB) when built on an E-UTRA radio.

[0003] In a non-terrestrial network (NTN), a satellite or an airborne vehicle may be used as a relay node and / or base station in a wireless communication system. The NTN architecture relies on radio access between a terrestrial terminal (e.g., user equipment (UE)) and a satellite (i.e., a service link). In addition, the satellite also requires radio access to a terrestrial gateway (i.e., a feeder link). The signaling / data exchange between the UE and the satellite occurs during a store-and-forward (S&F) operation without the satellite being simultaneously connected to the terrestrial network (i.e., a satellite may operate a service link without an active feeder link connection). Summary of the invention

[0004] According to some example embodiments, a method may include: establishing, by a first satellite, a connection with at least one satellite of a plurality of satellites. The method may also include: generating, by the first satellite, an SSG including at least one satellite of the plurality of satellites, the plurality of satellites including the first satellite. The method may also include: sending, by the first satellite, an indication of the plurality of satellites of the SSG to an AMF.

[0005] According to certain example embodiments, an apparatus may include means for establishing a connection with at least one satellite of a plurality of satellites. The apparatus may also include means for generating an SSG including at least one satellite of the plurality of satellites, the plurality of satellites including a first satellite. The apparatus may also include means for sending an indication of the plurality of satellites of the SSG to an AMF.

[0006] According to various example embodiments, a non-transitory computer-readable medium may include program instructions that, when executed by an apparatus, cause the apparatus to at least perform a method. The method may include establishing a connection with at least one of a plurality of satellites. The method may also include generating an SSG including at least one of the plurality of satellites, the plurality of satellites including a first satellite. The method may also include sending an indication of the plurality of satellites of the SSG to an AMF.

[0007] According to some example embodiments, a computer program product may perform a method. The method may include establishing a connection with at least one satellite of a plurality of satellites. The method may also include generating an SSG including at least one satellite of the plurality of satellites, the plurality of satellites including a first satellite. The method may also include sending an indication of the plurality of satellites of the SSG to an AMF.

[0008] According to certain example embodiments, an apparatus may include at least one processor and at least one memory storing instructions that, when executed by the at least one processor, cause the apparatus to at least: establish a connection with at least one satellite of a plurality of satellites. The at least one memory and the instructions when executed by the at least one processor further cause the apparatus to at least: generate an SSG including at least one satellite of the plurality of satellites, the plurality of satellites including a first satellite. The at least one memory and the instructions when executed by the at least one processor further cause the apparatus to at least: send an indication of the plurality of satellites of the SSG to an AMF.

[0009] According to various example embodiments, an apparatus may include establishing circuitry configured to perform: establishing a connection with at least one satellite of a plurality of satellites. The apparatus may also include generating circuitry configured to perform: generating an SSG including at least one satellite of the plurality of satellites, the plurality of satellites including a first satellite. The apparatus may also include sending circuitry configured to perform: sending an indication of the plurality of satellites of the SSG to an AMF.

[0010] According to some example embodiments, a method may include sending, by an AMF, at least one paging request from a first satellite of a plurality of satellites.

[0011] According to certain example embodiments, an apparatus may include means for transmitting at least one paging request from a first satellite of a plurality of satellites.

[0012] According to various example embodiments, a non-transitory computer-readable medium may include program instructions that, when executed by an apparatus, cause the apparatus to at least perform a method. The method may include sending at least one paging request from a first satellite of a plurality of satellites.

[0013] According to some example embodiments, a computer program product may perform a method. The method may include transmitting at least one paging request from a first satellite of a plurality of satellites.

[0014] According to certain example embodiments, an apparatus may include at least one processor and at least one memory storing instructions that, when executed by the at least one processor, cause the apparatus to at least: transmit at least one paging request from a first satellite of a plurality of satellites.

[0015] According to various example embodiments, an apparatus may include transmitting circuitry configured to perform: transmitting at least one paging request from a first satellite of a plurality of satellites. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] For a proper understanding of the example embodiments, reference should be made to the accompanying drawings, in which:

[0017] Figure 1 An overview diagram showing the regenerative satellite mode of operation;

[0018] Figure 2 An example of a serving satellite change during a feeder link disconnection with a moving user device is shown;

[0019] Figure 3 Another example of a serving satellite change during a feeder link disconnection from a moving satellite is shown;

[0020] Figure 4 An example of a user plane protocol stack is shown;

[0021] Figure 5 An example of a control plane protocol stack is shown;

[0022] Figure 6 An example signaling diagram is shown;

[0023] Figure 7 Examples of selective satellite groups are shown in accordance with various example embodiments;

[0024] Figure 8 shows an example of a signaling diagram according to certain example embodiments;

[0025] Fig. 9 An example of a flow chart illustrating a method according to various example embodiments;

[0026] Fig.10 An example of a flow chart illustrating a method according to a certain example embodiment;

[0027] Fig.11 illustrates examples of various network devices according to some example embodiments; and

[0028] Fig.12 Examples of 5G network and system architectures are shown in accordance with certain example embodiments. DETAILED DESCRIPTION

[0029] It will be readily appreciated that the components of the particular example embodiments, as generally described and illustrated in the figures herein, may be arranged and designed in a variety of different configurations. Therefore, the following detailed description of some example embodiments of systems, methods, apparatuses, and computer program products for establishing an NTN satellite constellation is not intended to limit the scope of the particular example embodiments, but rather represents selected example embodiments.

[0030] NTN may refer to a network or a collection of networks that utilize radio frequency (RF) resources via a satellite (or an unmanned aircraft system (UAS) platform). In particular, the NTN may include UEs (or IoT devices) connected to a satellite via a service link. The satellite may be connected to an NTN gateway via a feeder link, and the NTN gateway may be connected to a core network and / or a home network.

[0031] The RAN architecture can support satellite protocols through various satellite payloads. For example, in a transparent satellite payload scenario, the satellite may not terminate NR-Uu, but instead repeat the NR-Uu radio interface between the feeder link and the serving link.

[0032] Figure 1A regenerative satellite mode of operation is shown, where the satellite acts as a base station (e.g., gNB) between the UE and the NTN gateway (i.e., the terrestrial network). In this regenerative satellite payload scenario, the satellite can support all radio network layer protocols and regeneration can be achieved if the RF signal is received from Earth. Because the satellite handles the payload, the satellite can store and forward information, and the satellite can establish communications with neighbor satellites via inter-satellite links (ISLs). Figure 1 As shown in , the satellite supports and provides complete base station (i.e., gNB) functionality, including all required radio network layer (RNL) protocols. A Uu interface (e.g., service link) can be established between the satellite and the UE (e.g., IoT). In addition, a NG interface (e.g., feeder link) can be established between the satellite and the access and mobility management function (AMF), where the NG interface is routed through the NTN gateway. One difference between the regenerative and transparent payload architectures is that in the regenerative payload, all gNB functionality is incorporated into the satellite itself to enable faster scheduling decisions and shorter round-trip time (RTT).

[0033] A remote monitoring UE (e.g., IoT) may need to send a message to an application server that provides a remote monitoring service. The UE may wait for satellite network coverage before sending a message. The remote monitoring UE may interact with a satellite providing coverage via a service link, allowing the UE to transmit messages to a satellite that has no physical connection to the terrestrial network. Therefore, the satellite must store the received messages locally. A 5G system with satellite access may support store-and-forward operations, notify the UE that a store-and-forward operation has been applied, and / or provide integrity protection and confidentiality for communications between authorized UEs and the network when a store-and-forward operation is applied.

[0034] The remote monitoring service application server may need to send new parameters to the IoT remote monitoring UE. Based on the information provided by the network, the application server can know that the communication with the UE is in a store-and-forward mode of operation. The remote monitoring service application server message will send new parameters to the network entry point (e.g., service capability exposure function (SCEF), packet data network (PDN) gateway (GW), short message service center (SMSC)) via a dedicated message via conventional means (e.g., IP routing, tunnel), and may provide additional information to the network (e.g., transmission priority, acknowledgment (ACK)). In this architecture, restrictions can be imposed on the amount of data to be transmitted to the IoT remote monitoring UE, and priorities can be established for forwarding to the UE. In addition, an ACK for data received by the network can be sent back to the application server, which may include additional information about storage and forwarding (e.g., estimated time to transmit the message). An end-to-end ACK policy can also be established.

[0035] The network can store the message until the message can be transmitted / relayed to the satellite that provides coverage to the destination IoT remote monitoring UE. When the satellite is connected to the ground network via a feeder link, the message can be uploaded to the satellite. All accumulated and stored mobile terminated (MT) messages can be uploaded to the satellite via the feeder link. At the same time, the accumulated and stored mobile initiated (MO) messages can be transmitted to the 5G core (e.g., the next generation core (NGC)) via the same feeder link, which may reduce the performance of the feeder link, the satellite and / or the 5GC without a performance optimization method. When providing coverage to the IoT remote monitoring UE, the satellite with the stored message can trigger paging on the service link so that the UE is connected to the network. The stored message can be transmitted / downloaded from the satellite to the IoT remote monitoring UE, and ACK can be requested and provided. There can also be technology to ensure the integrity of the transmitted information. A 5G system with satellite access can notify a trusted application server whether a store and forward operation is applied to communication with the UE, and / or provide integrity protection and confidentiality for communications between authorized UEs and the network when the store and forward operation is applied.

[0036] Figure 2 The figure shows a change of serving satellites during a feeder link disconnection when the IoT device is moving. In particular, a mobile IoT device can move from the coverage of one satellite to the coverage of another satellite (e.g., container tracking and tracing), or as Figure 3As shown in , a non-geostationary orbit (NGSO) satellite can move out of coverage, and a second satellite can move into coverage and start serving static IoT devices. In this case, the original service satellite can forward the stored user plane data to a subsequent service satellite via an ISL, and the subsequent service satellite can forward the data to a gateway. At the same time, if the feeder link of the subsequent satellite is also unavailable, the subsequent satellite can continue the storage operation until its feeder link is reactivated. Therefore, for each IoT device, there can be only one satellite in the overall satellite system for data storage of the IoT device. Mobile operators can also manage and maintain their data more easily, rather than managing the individual data of a device across multiple satellites. When the feeder link is unavailable, the service satellite can only store and forward (e.g., via an ISL) data received from an IoT device that can send data to an application server via a mobile network with satellite access. Because the link disconnection may temporarily cut off part of the mobile network, the service satellite may not be able to implement common communication processes and may deny access to unregistered devices. In addition, considering the limited data storage in the satellite and the large number of IoT devices, the maximum storage of each IoT device can be pre-configured based on application data characteristics, user subscriptions, and / or the overall performance of the satellite communication system. Depending on the operator's strategy, a 5G system with satellite access can support forwarding stored data received from an authorized UE using delay-tolerant communication services from one satellite to another over an ISL while maintaining integrity protection, confidentiality, and security of the data.

[0037] Figure 4 The user plane protocol stack is shown, as well as the communication between the IoT UE, the home network (HN), the remote monitoring service application server, the non-access stratum (NAS), and the user plane (UP). In this case, the end-to-end communication path between the UE (IoT) device and the user plane function (UPF) is shown. An application function (AF) that sends device data (e.g., protocol data unit (PDU)) to the UE (IoT) or receives device data (e.g., protocol data unit (PDU)) from the UE (IoT) can be connected to the UPF. Packet data convergence protocol (PDCP) security can be implemented between the UE (IoT) and the satellite A. The device data (e.g., PDU) can be transmitted via the service data adaptation protocol (SDAP) (e.g., Uu interface) and can be protected by PDCP (e.g., AS security). The device data (e.g., PDU) can be transmitted via the general packet radio service (GPRS) tunneling protocol (GTP)-u (NG interface) and can be protected by the network directory server (NDS) / Internet protocol security (IPsec) and / or datagram transport layer security (DTLS).

[0038] Figure 5 The control plane protocol stack is shown, where the end-to-end communication path is between the UE (IoT) and the gNB (e.g., Radio Resource Control (RRC) protocol), which may include the AS, or between the UE (IoT) and the AMF (e.g., NAS protocol). The AF that sends or receives device data (e.g., PDU) to or from the UE (IoT) may be connected to the AMF. The device data (e.g., PDU) may be transmitted end-to-end through the NAS and may be protected by NAS security.

[0039] The store and forward operation may be in a normal / default satellite operation mode. For example, when the feeder link and the serving link are available, the UE(IoT) device may be authenticated by the core network and the UE(IoT) may establish an RRC connection with the serving satellite. In this normal / default operation mode, NAS and AS security contexts may be established and maintained. The UE(IoT) device may change between different RRC modes.

[0040] Alternatively, the store and forward operation may be in a store and forward satellite mode of operation, where the feeder link (i.e., step A) or the service link (i.e., step B) is not active. Thus, the satellite may move from being connected to the UE in step A to being connected to the terrestrial network in step B. This store and forward satellite mode of operation may provide AS and NAS mobility, where the UE (IoT) or satellite moves while the AS / NAS context exists. For these mobility scenarios, since AS mobility may refer to the UE (IoT) or satellite on the move, the AS (security) context may need to be moved to a new target satellite; NAS mobility may refer to the NAS (security) context needing to be moved to a new home network. The mapping may be summarized in the following table:

[0041] model AS Context NAS Context "Normal / Default" Establish Establish "Store and Forward Satellite" Established when AS moves Create when NAS is moved

[0042] like Figure 6 As shown in , at operation 601, the UE may perform primary authentication via SAT#3 (satellite#3) and receive services from the 5G core network (i.e., NGC). At operation 602, SAT#3 may then no longer provide coverage and the feeder link may be lost. However, at operation 603, the AMF may need to send a message (e.g., PDU) to the UE, but cannot do so because there is no longer an active feeder link with SAT#3, as shown in operation 604.

[0043] Certain example embodiments described herein may have various benefits and / or advantages to overcome the disadvantages described above. For example, if the satellite initiating the primary authentication (pSAT) moves (e.g., due to AS mobility) and a new satellite (i.e., the secondary SAT) begins serving the UE during the primary authentication and AS security context establishment, certain example embodiments may determine which satellite will be responsible for maintaining the AS security context.

[0044] When a satellite may not be able to maintain a service and / or feeder link, certain example embodiments enable the primary satellite to be aware of at least one satellite in the group that is maintaining a lost service / feeder link. Because the primary satellite can move with the service link, some example embodiments can reduce the number of required satellites by at least two. In addition, the moving primary satellite can also move the access layer security context (partially or completely), thereby eliminating any requirement to re-register the UE for AS security context establishment. The primary satellite can also perform secondary satellite authentication, thereby improving the reliability and accuracy of selecting a satellite group. In various example embodiments, the primary satellite can also perform satellite group lifecycle management, such as adding or removing satellites from the group, including related context information. Therefore, the specific example embodiments discussed below are intended to improve computer-related technologies.

[0045] Certain example embodiments may include establishing a selective satellite group (SSG) where each satellite with an active service link to the UE / IoT may act as a pSAT and / or establish communication links with neighboring satellites. The pSAT may establish a satellite group that may be used to transmit UE / IoT context and / or data. If the UE / IoT or the pSAT moves such that the UE / IoT is no longer within the coverage of the pSAT, the pSAT functionality is assigned to a new pSAT. The AMF may select other satellites to page the UE, and the other satellites may forward their paging requests to the new pSAT. In some example embodiments, SSG information may be provided to the AMF, enabling the AMF to select at least one alternative satellite to page the UE.

[0046] In various example embodiments, the AF may need to connect to a specific UE (IoT) (i.e., in order to share data) by triggering a UE (IoT) paging procedure to page the UE (IoT). Figure 7In the architecture 700 shown in FIG. 7 , the AMF 770 may be connected to the AF 780, and to the satellites SAT#1, SAT#2, and SAT#3 in the SSG 720 via the NTN GW 760 through the corresponding feeder links 730, 740, and 750. The UE (IoT) 710 may be connected to SAT#3. If the AMF 770 sends paging information for the UE (IoT) 710, but the feeder link #3 750 between the AMF 770 and SAT#3 is unavailable or otherwise inactive, the AMF 770 may not be able to connect directly with the UE (IoT) 710 because the UE (IoT) 710 is connected to SAT#3, but SAT#3 does not have an active feeder link (i.e., the feeder link 750 is inactive).

[0047] SAT#3 may act as a pSAT and / or establish an SSG, which may include at least two satellites (i.e., one pSAT and at least one secondary SAT (sSAT)). Satellites may be added to or deleted from the SSG. The pSAT may maintain inter-SAT communications (e.g., a star topology) with each sSAT. Figure 7 The star topology shown in can be a logical inter-SAT deployment, where each satellite that maintains an active service link to a UE (IoT) acts as a pSAT.

[0048] like Figure 7 As shown in , the pSAT can maintain direct communication with the UE (IoT) and, as a pSAT, can perform UE authentication, receive auxiliary node keys (KgNB) and / or manage SSG. If the UE (IoT) moves out of the coverage of SAT #1 (i.e., pSAT) and moves into the coverage of an sSAT (e.g., SAT #2), all pSAT roles and responsibilities can be transferred to SAT #2 as the new pSAT (e.g., via a traditional handover process). Therefore, since the feeder link (#3) is unavailable, SAT #2 acts as a proxy / relay with the HN / AMF / AUSF / UDM.

[0049] Figure 8 An example of a signaling diagram 800 depicting a UE paging procedure is shown. According to certain example embodiments, UE 820 may be similar to UE 1120, and SAT 830, SAT 840, SAT 850, SAT 860 and AMF / CN 870 may be similar to NE 1110 (eg, Fig.11 ).

[0050] At operation 801, UE 820 may be connected to SAT 830 via a service link. SAT 830 may act as a pSAT for UE 820. SAT 830 may own KgNBs of SATs 830-860 and / or may generate KgNBs according to a key hierarchy.

[0051] In operation 802, SAT 830 may generate an SSG and establish connections with SATs 840-860 (which may belong to the generated SSG).

[0052] In a specific example embodiment, at operation 803, SAT 830 may send a notification of the generated SSG to AMF / CN 870, which may indicate that SATs 840-860 are backup sSATs. At operation 804, AMF / CN 870 may store the generated SSG to the UE context because UE 820 has registered with AMF / CN 870. If AMF / CN 870 receives the notification of the secondary satellite group, AMF / CN 870 may associate the SSG with the UE context, thereby enabling AMF / CN 870 to know which UE context is served by which SSG. In addition, at operation 805, SAT 830 may send a notification of the generated SSG to SAT 840, and similarly, at operation 806, SAT 830 may send a notification of the generated SSG to SAT 850 (and each SAT included in the SSG, until SAT 860).

[0053] At operation 807, SAT 830 may lose the active feeder link with AMF / CN 870 and may send a notification of the lost / inactive feeder link to SAT 840-860. Additionally, in the event of UE handover, SAT 830 may manage the KgNB to be shared with SAT 840-860. This information may be exchanged via RRC.

[0054] At operation 808, the AMF / CN 870 may trigger a paging procedure for the UE 820 via the active feeder link of the SAT 840-860. The AMF / CN 870 may then send a paging message to the SAT 840-860.

[0055] In various example embodiments, if AMF / CN 870 determines that one of SATs 840-860 is inaccessible, AMF / CN 870 may trigger a paging procedure for UE 820 via any of SATs 840-860 with an active feeder link. For example, AMF / CN 870 may send a paging message toward SAT 840 and / or SAT 850.

[0056] In operation 809, any one of the SATs 840-860 may receive a paging request for the UE 820. However, only one of the SATs 840-860 may receive the paging request.

[0057] In operation 810, the SATs 840-860 (which can only be one of the SATs 840-860) that received the paging request from the AMF / CN 870 may page the UE 820 within their own tracking areas.

[0058] In operation 811, the SAT 840-860 (which can only be one of the SATs 840-860) that receives the paging request from the AMF / CN 870 may forward the paging request to the SAT 830 (the SAT 830 loses the active feeder link with the AMF / CN 870). Therefore, the SAT 830 may receive the paging request from one or more of the SATs 840-860.

[0059] At operation 812, the SAT 830 may page the UE 820 within its own tracking area (eg, via the Xn Application Protocol (XnAP)). Once the UE 820 receives the page from the SAT 830, the UE 820 may respond by triggering a random access procedure.

[0060] Fig. 9 It shows that a NE (e.g. Fig.11 An example of a flowchart of method 900 performed by NE 1110) shown in FIG.

[0061] At step 901, the method may include establishing, by a first satellite, a connection with at least one satellite among a plurality of satellites.

[0062] At step 902, the method may further include generating, by the first satellite, an SSG including at least one satellite of a plurality of satellites, the plurality of satellites including the first satellite.

[0063] In step 903, the method may further include: sending, by the first satellite, an indication of multiple satellites of the SSG to the AMF.

[0064] In certain example embodiments, the method may further include sending, by the first satellite to at least one satellite of the plurality of satellites of the SSG, an indication indicating an inactive or lost feeder link.

[0065] In some example embodiments, the method may further include managing, by the first satellite, at least one key configured to be shared by at least one satellite of a plurality of satellites associated with user equipment handover.

[0066] In various example embodiments, the method may further include: receiving, by the first satellite, at least one message request from the AMF. The first satellite may have at least one active connection with the AMF. The at least one active connection with the AMF may include an available feeder link. The method may further include: sending, by the first satellite, a message to at least one other satellite in the SSG connected to the UE in response to the at least one message request.

[0067] In a specific example embodiment, the method may further include: receiving, by the first satellite, at least one message request from at least one other satellite in the SSG connected to the UE. The method may further include: sending, by the first satellite, a message to at least one other satellite in the SSG connected to the AMF in response to the at least one message request. The message may include at least one of: a paging message, a registration procedure, a UE registration procedure, an authentication procedure, an uplink message, a downlink message, a control message, or a user plane message.

[0068] In some example embodiments, the first satellite may maintain a feeder link to the AMF. The AMF may belong to the core network. The first satellite may include a network entity.

[0069] In various example embodiments, the method may further include modifying, by the first satellite, the SSG by adding or deleting satellites of the SSG.

[0070] Fig.10 It shows that a NE (e.g. Fig.11 An example of a flowchart of method 1000 performed by NE 1110) shown in FIG.

[0071] At step 1001, the method may include sending, by the AMF, at least one paging request from a first satellite among a plurality of satellites.

[0072] In a specific example embodiment, the method may further include: modifying, by the AMF, the SSG by adding or deleting satellites of the SSG.

[0073] In some example embodiments, the AMF comprises a network entity.

[0074] In various example embodiments, the method may further include: receiving, by the AMF, an indication of a plurality of satellites of the SSG from the first satellite. The method may further include: generating, by the AMF, an indication configured to generate SSG information of the SSG; and sending, by the AMF, the indication to the first satellite.

[0075] In a specific example embodiment, the method may further include: sending, by the AMF, at least one message request to the first satellite. The AMF has at least one active connection with the first satellite. The at least one active connection with the AMF may include an available feeder link.

[0076] In some example embodiments, the AMF may maintain a feeder link to the first satellite. The AMF may belong to the core network.

[0077] Fig.11 An example of a system according to certain example embodiments is shown. In an example embodiment, the system may include a plurality of devices, such as NE 1110 and / or UE 1120 .

[0078] NE 1110 may be one or more of: a base station (e.g., a 3G UMTS Node B, a 4G LTE Evolved Node B, or a 5G NR Next Generation Node B), a serving gateway, a server, and / or any other access node or a combination thereof.

[0079] NE 1110 may also include at least one gNB-centralized unit (CU), which may be associated with at least one gNB-distributed unit (DU). The at least one gNB-CU and the at least one gNB-DU may communicate with each other via at least one F1 interface, at least one X n -C interface, and / or communicate via at least one NG interface of the fifth generation core (5GC).

[0080] UE 1120 may include one or more of the following: a mobile device (e.g., a mobile phone), a smart phone, a personal digital assistant (PDA), a tablet or portable media player, a digital camera, a pocket camcorder, a video game console, a navigation unit (e.g., a global positioning system (GPS) device), a desktop or laptop computer, a single-location device (e.g., a sensor or smart meter), or any combination thereof. In addition, NE 1110 and / or UE 1120 may be one or more of a Citizen Broadband Radio Service Device (CBSD).

[0081] NE 1110 and / or UE 1120 may include at least one processor, indicated as 1111 and 1121, respectively. Processors 1111 and 1121 may be embodied by any computing or data processing device, such as a central processing unit (CPU), an application specific integrated circuit (ASIC), or the like. The processor may be implemented as a single controller or multiple controllers or processors.

[0082] At least one memory may be provided in one or more devices, as indicated by 1112 and 1122. The memory may be fixed or removable. The memory may include computer program instructions or computer codes contained therein. Memories 1112 and 1122 may independently be any suitable storage device, such as a non-transitory computer-readable medium. As used herein, the term "non-transitory" may correspond to limitations of the medium itself (e.g., tangible, not a signal), rather than limitations on data storage persistence (e.g., random access memory (RAM) versus read-only memory (ROM)). A hard disk drive (HDD), random access memory (RAM), flash memory, or other suitable memory may be used. The memory may be combined on a single integrated circuit as a processor, or may be separated from one or more processors. In addition, the computer program instructions stored in the memory and that may be processed by the processor may be computer program codes in any suitable form, such as a compiled or interpreted computer program written in any suitable programming language.

[0083] Processors 1111 and 1121, memories 1112 and 1122, and any subset thereof may be configured to provide Figure 7-10 Components corresponding to the various blocks of . Although not shown, the device may also include positioning hardware (e.g., GPS) or micro-electromechanical system (MEMS) hardware, which can be used to determine the location of the device. Other sensors are also allowed and can be configured to determine location, altitude, speed, orientation, etc., such as a barometer, compass, etc.

[0084] like Fig.11 As shown in , transceivers 1113 and 1123 may be provided, and one or more devices may also include at least one antenna, indicated as 1114 and 1124, respectively. The device may have many antennas, such as an antenna array configured for multiple-input multiple-output (MIMO) communication, or multiple antennas for multiple RATs. For example, other configurations of these devices may be provided. Transceivers 1113 and 1123 may be transmitters, receivers, both transmitters and receivers, or units or devices that may be configured for both transmission and reception.

[0085] The memory and the computer program instructions may be configured to, together with the processor of a specific device, cause the hardware device (eg, UE) to perform the above (ie, Figure 7-10 ). Thus, in certain example embodiments, a non-transitory computer-readable medium may be encoded with computer instructions that, when executed in hardware, perform a process, such as one of the processes described herein. Alternatively, certain example embodiments may be performed entirely in hardware.

[0086] In certain example embodiments, an apparatus may include a Figure 7-10 As used in this application, the term "circuit" may refer to one or more or all of the following: (a) a pure hardware circuit implementation (e.g., an implementation in a pure analog and / or digital circuit); (b) a combination of hardware circuits and software, such as (as applicable): (i) a combination of analog and / or digital hardware circuits and software / firmware, and (ii) any portion of a hardware processor (including a digital signal processor) with software, software, and memory that work together to enable a device (e.g., a mobile phone or server) to perform various functions; and (c) a hardware circuit and / or processor (e.g., a microprocessor or a portion of a microprocessor) that requires software (e.g., firmware) to operate, but the software may not be present when it is not required for operation. This "circuit" definition applies to all uses of the term in this application (including in any claims). As a further example, as used in this application, the term "circuit" also covers an implementation of only a hardware circuit or processor (or multiple processors) or a portion of a hardware circuit or processor and its accompanying software and / or firmware. The term "circuitry" also covers (for example and if applicable to a particular claim element) a baseband integrated circuit or a processor integrated circuit for a mobile device, or a similar integrated circuit in a server, cellular network device, or other computing or networking equipment.

[0087] Fig.12 Examples of 5G network and system architectures according to certain example embodiments are shown. A number of network functions are shown, which may be implemented as software operating as part of a network device or dedicated hardware, as a network device itself or dedicated hardware, or as virtual functions operating as a network device or dedicated hardware. Fig.12 The NE and UE shown in the figure may be similar to NE 1110 and UE 1120, respectively. The user plane function (UPF) may provide services such as intra-RAT and inter-RAT mobility, routing and forwarding of data packets, inspection of packets, user plane quality of service (QoS) processing, buffering of downlink packets, and / or triggering of downlink data notifications. The AF may primarily interface with the core network to facilitate application use of service routing and interact with the policy framework.

[0088] According to certain example embodiments, the processors 1111 and 1121 and the memories 1112 and 1122 may be included in a processing circuit or a control circuit, or may form a part of a processing circuit or a control circuit. In addition, in some example embodiments, the transceivers 1113 and 1123 may be included in a transceiver circuit, or may form a part of a transceiver circuit.

[0089] In some example embodiments, an apparatus (e.g., NE 1110 and / or UE 1120) may include components for performing the methods, processes, or any variants discussed herein. Examples of components may include one or more processors, memories, controllers, transmitters, receivers, and / or computer program codes for causing operations to be performed.

[0090] In various example embodiments, the apparatus 1110 may be controlled by the memory 1112 and the processor 1111 to establish a connection with at least one of a plurality of satellites; generate an SSG including at least one of a plurality of satellites, the plurality of satellites including a first satellite; and send an indication of the plurality of satellites of the SSG to the AMF.

[0091] Certain example embodiments may be directed to an apparatus comprising means for performing any of the methods described herein, including, for example, means for establishing a connection with at least one of a plurality of satellites; means for generating an SSG comprising at least one of a plurality of satellites, the plurality of satellites including a first satellite; and means for sending an indication of the plurality of satellites of the SSG to an AMF.

[0092] In various example embodiments, the apparatus 1110 may be controlled by the memory 1112 and the processor 1111 to transmit at least one paging request from a first satellite of the plurality of satellites.

[0093] Certain example embodiments may be directed to an apparatus comprising means for performing any of the methods described herein, including, for example, means for transmitting at least one paging request from a first satellite of a plurality of satellites.

[0094] The features, structures, or characteristics of the example embodiments described in this specification may be combined in one or more example embodiments in any suitable manner. For example, the use of the phrases "various embodiments," "specific embodiments," "some embodiments," or other similar language in this specification refers to the fact that a particular feature, structure, or characteristic described in conjunction with the example embodiments may be included in at least one example embodiment. Therefore, the phrases "in various embodiments," "in specific embodiments," "in some embodiments," or other similar language appearing in this specification do not necessarily refer to the same set of example embodiments, and the described features, structures, or characteristics may be combined in one or more example embodiments in any suitable manner.

[0095] As used herein, “at least one of: ” and “at least one of ” and similar expressions (wherein a list of two or more elements is connected by “and” or “or”) mean at least any one element, or at least any two or more elements, or at least all the elements.

[0096] Additionally, if desired, the different functions or processes discussed above may be performed in different orders and / or simultaneously with each other. Furthermore, if desired, one or more functions or processes described may be optional or may be combined. Therefore, the above description should be viewed as an illustration of the principles and teachings of specific example embodiments, rather than as a limitation thereof.

[0097] Those of ordinary skill in the art will readily appreciate that the example embodiments discussed above may be practiced using processes in a different order, and / or using hardware elements in configurations other than those disclosed. Therefore, although some embodiments have been described based on these example embodiments, those skilled in the art will appreciate that certain modifications, variations, and alternative configurations will be apparent while still within the spirit and scope of the example embodiments.

[0098] Partial Glossary

[0099] 3GPP Third Generation Partnership Project

[0100] 5G fifth generation

[0101] 5GC fifth generation core

[0102] 6G Sixth Generation

[0103] ACK

[0104] AF application function

[0105] AMF access and mobility management function

[0106] AS access layer

[0107] ASIC

[0108] BS Base Station

[0109] CBSD Citizens Broadband Radio Service Equipment

[0110] CPU Central Processing Unit

[0111] CU Centralized Unit

[0112] DTLS Datagram Transport Layer Security

[0113] DU Distributed Unit

[0114] eMBB Enhanced Mobile Broadband

[0115] eNB Evolved Node B

[0116] gNBNext Generation Node B

[0117] GPRS General Packet Radio Service

[0118] GPS Global Positioning System

[0119] GTP General Packet Radio Service Tunneling Protocol

[0120] GW Gateway

[0121] HDD Hard Drive

[0122] HN Home Network

[0123] IoT

[0124] ISL Inter-Satellite Link

[0125] IPS Internet Protocol Security

[0126] KgNB auxiliary node key

[0127] LTE Long Term Evolution

[0128] LTE-A Long Term Evolution Advanced

[0129] MEMS Micro-Electro-Mechanical Systems

[0130] MIMO Multiple Input Multiple Output

[0131] mMTC massive machine type communications

[0132] MO Mobile initiated

[0133] MT Mobile Terminated

[0134] NAS non-access layer

[0135] NDS Network Directory Server

[0136] NE network entity

[0137] NG Next Generation

[0138] NGC Next Generation Core

[0139] NG-eNB Next Generation Evolved Node B

[0140] NG-RAN Next Generation Radio Access Network

[0141] NGSO Non-Geostationary Orbit

[0142] NR New Radio

[0143] NTN Non-terrestrial Network

[0144] PDA Personal Digital Assistant

[0145] PDCP Packet Data Convergence Protocol

[0146] PDN Packet Data Network

[0147] PDU protocol data unit

[0148] pSAT primary satellite

[0149] QoS Quality of Service

[0150] RACH Random Access Channel

[0151] RAM Random Access Memory

[0152] RAN Radio Access Network

[0153] RAP Radio Access Procedure

[0154] RAT Radio Access Technology

[0155] RF

[0156] RNL Radio Network Layer

[0157] ROM Read Only Memory

[0158] RRC Radio Resource Control

[0159] RTT Round Trip Time

[0160] pSAT primary satellite

[0161] S&F Store and Forward

[0162] SCEF service capability exposure function

[0163] SDAP Service Data Adaptation Protocol

[0164] SMSC Short Message Service Center

[0165] sSAT auxiliary satellite

[0166] SSG Selective Satellite Group

[0167] UAS Unmanned Aerial Vehicle System

[0168] UE User Equipment

[0169] UMTS Universal Mobile Telecommunications System

[0170] UP user plane

[0171] UPF user plane function

[0172] URLLC ultra-reliable and low-latency communications

[0173] UTRAN Universal Mobile Telecommunications System Terrestrial Radio Access Network

[0174] XnAP Xn Application Protocol

Claims

1. A method comprising: establishing, by the first satellite, a connection with at least one satellite of the plurality of satellites; generating, by the first satellite, a selective satellite group including at least one satellite of the plurality of satellites, the plurality of satellites including the first satellite; as well as An indication of the plurality of satellites of the selective set of satellites is sent by the first satellite to an access and mobility management function.

2. A method comprising: At least one paging request from a first satellite of the plurality of satellites is sent by an access and mobility management function.

3. A device comprising: at least one processor; as well as at least one memory storing instructions that, when executed by the at least one processor, cause the apparatus to at least: establishing a connection with at least one satellite of a plurality of satellites; generating a selective satellite group including at least one satellite of the plurality of satellites, the plurality of satellites including the first satellite; as well as An indication of the plurality of satellites of the selective set of satellites is sent to an access and mobility management function.

4. The device according to claim 3, wherein: The at least one memory and the instructions when executed by the at least one processor further cause the apparatus to at least: An indication is sent to at least one satellite of the plurality of satellites of the selective set of satellites indicating an inactive or lost feeder link.

5. The device according to claim 3, wherein: The at least one memory and the instructions when executed by the at least one processor further cause the apparatus to at least: At least one key is managed, the at least one key configured to be shared by at least one satellite of the plurality of satellites associated with a handover of a user equipment.

6. The device according to claim 3, wherein: The at least one memory and the instructions when executed by the at least one processor further cause the apparatus to at least: At least one message request is received from the access and mobility management function, wherein the first satellite has at least one active connection with the access and mobility management function.

7. The device according to claim 6, wherein: The at least one active connection with the access and mobility management function comprises an available feeder link.

8. The device according to claim 6, wherein: The at least one memory and the instructions when executed by the at least one processor further cause the apparatus to at least: In response to the at least one message request, a message is sent to at least one other satellite in the selective set of satellites that is connected to the user equipment.

9. The device according to claim 3, wherein: The at least one memory and the instructions when executed by the at least one processor further cause the apparatus to at least: At least one message request is received from at least one other satellite in the selective set of satellites that is connected to the user equipment.

10. The device according to claim 9, wherein: The at least one memory and the instructions when executed by the at least one processor further cause the apparatus to at least: In response to the at least one message request, a message is sent to at least one other satellite in the selective set of satellites connected to the access and mobility management function.

11. The device according to claim 6, wherein: The message includes at least one of the following: a paging message, a registration procedure, a UE registration procedure, an authentication procedure, an uplink message, a downlink message, a control message, or a user plane message.

12. The device according to claim 3, wherein: The first satellite maintains a feeder link to the access and mobility management function.

13. The device according to claim 3, wherein: The access and mobility management functions belong to the core network.

14. The device according to claim 3, wherein: The first satellite includes a network entity.

15. The device according to any one of claims 3 to 14, wherein: The at least one memory and the instructions when executed by the at least one processor further cause the apparatus to at least: The selective set of satellites is modified by adding or deleting satellites from the selective set of satellites.

16. An apparatus comprising: at least one processor; as well as at least one memory storing instructions that, when executed by the at least one processor, cause the apparatus to at least: At least one paging request from a first satellite of the plurality of satellites is transmitted.

17. The device according to claim 16, wherein: The at least one memory and the instructions when executed by the at least one processor further cause the apparatus to at least: The selective set of satellites is modified by adding or deleting satellites therefrom.

18. The device according to claim 16, wherein: The apparatus comprises a network entity.

19. The device according to claim 16, wherein: The at least one memory and the instructions when executed by the at least one processor further cause the apparatus to at least: An indication of the plurality of satellites of a selective set of satellites is received from a first satellite.

20. The device according to claim 19, wherein The at least one memory and the instructions when executed by the at least one processor further cause the apparatus to at least: generating an indication configured to generate selective satellite group information of the selective satellite group; and The indication is sent to the first satellite.

21. The device according to claim 16, wherein: The at least one memory and the instructions when executed by the at least one processor further cause the apparatus to at least: At least one message request is sent to the first satellite, wherein the apparatus has at least one active connection with the first satellite.

22. The device according to claim 21, wherein The at least one active connection with the device comprises an available feeder link.

23. The device according to claim 16, wherein: The device maintains a feeder link to the first satellite.

24. The device according to any one of claims 16 to 23, wherein: The device belongs to a core network.

25. A non-transitory computer-readable medium storing program instructions, which, when executed by a device, cause the device to perform the method according to any one of claims 1-2.

26. An apparatus comprising a circuit configured to perform the method according to any one of claims 1-2.

27. A computer program product comprising instructions which, when executed by an apparatus, cause the apparatus to perform the method according to any one of claims 1-2.

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