Triggering of user equipment recovery procedure for store-and-forward operation in ntn

Abstract

A method, apparatus, and computer program product for wireless communication are provided that include monitoring, by a user equipment, a satellite-specific procedure message provided by a second satellite, the satellite-specific procedure message relating to a first satellite to which the user equipment was previously connected; and upon detecting the provided second satellite, the satellite-specific message relating to the first satellite, triggering a resumption of a connection with the second satellite.

Description

Technical Field

[0001] The example embodiment generally relates to a store-and-forward satellite (S&F) operation that provides communication services to user equipment (UE) during time periods and / or geographical areas when the serving satellite is not simultaneously connected to a terrestrial network via a feeder link or inter-satellite link (ISL). Background Technology

[0002] In 5G systems, when satellite connectivity is intermittently / temporarily unavailable (between the UE and the satellite, and between the satellite and the core network node), service requirements for Mobile Initiated (MO) and Mobile Termination (MT) use cases can be provided to some extent using store-and-forward (S&F) satellite operations. Store-and-forward satellite (S&F) operations provide communication services to the UE during time periods and / or geographical areas when the serving satellite is not simultaneously connected to the terrestrial network via a feeder link or inter-satellite link (ISL).

[0003] In the case of uplink (UL), "store" refers to the onboard storage of UL information from the UE, and "forward" refers to forwarding the stored UL information to the terrestrial network. In the case of downlink (DL), "store" refers to the onboard storage of DL information from the terrestrial network, and "forward" refers to forwarding the stored DL information to the UE. Summary of the Invention

[0004] A user equipment (UE) (100) for wireless communication includes: at least one processor (410); and at least one memory (420) storing instructions that, when executed by the processor, cause the user equipment (100) to: monitor (316) a satellite-specific process message (148) provided by a second satellite (150), the satellite-specific process message (148) being associated with a first satellite (140) to which the user equipment (100) was previously connected; and, upon detecting the provided satellite-specific process message (148) associated with the first satellite (140), trigger a reconnection (318) with the second satellite (150).

[0005] A second non-terrestrial network node (150) for wireless communication includes: at least one processor (410); and at least one memory (420) storing instructions that, when executed by the processor, cause the second non-terrestrial network node (150) to: provide (step 314) a satellite-specific process message (148) to at least one user equipment (100), the at least one user equipment (100) being served by the second non-terrestrial network node (150) within a second coverage area (C2), the satellite-specific process message (148) being associated with a first non-terrestrial network node (140) serving a first service coverage area (C1); and to restore a connection with the at least one user equipment (100) within the second coverage area (C2), the at least one user equipment (100) having previously connected (202, 302) to the first non-terrestrial network node (140) within the first coverage area (C1) served by the first non-terrestrial network node (140).

[0006] A user equipment (UE) (100) for wireless communication includes: components for monitoring (316) a satellite-specific process message (148) provided by a second satellite (150), the satellite-specific process message (148) being associated with a first satellite (140) to which the user equipment (100) was previously connected; and components for triggering the restoration of connection (318) with the second satellite (150) upon detection of the provided satellite-specific process message (148) associated with the first satellite (140).

[0007] A second non-terrestrial network node (150) for wireless communication includes: components for providing (314) a satellite-specific process message (148) to at least one user equipment (100), the at least one user equipment (100) being served by the second non-terrestrial network node (150) in a second coverage area (C2), the satellite-specific process message (148) being associated with a first non-terrestrial network node (140) serving a first service coverage area (C1); and components for re-establishing a connection with the at least one user equipment (100) in the second coverage area (C2), the at least one user equipment (100) having previously connected (202, 302) to the first non-terrestrial network node (140) in the first coverage area (C1) served by the first non-terrestrial network node (140).

[0008] A computer-implemented method for wireless communication includes the steps of: monitoring (315) by a user equipment (100) a satellite-specific process message (148) provided by a second satellite (150), the satellite-specific process message (148) being associated with a first satellite (140) to which the user equipment (100) was previously connected; and triggering a reconnection (318) with the second satellite (150) upon detection of the provided second satellite (150) and the satellite-specific process message (148) associated with the first satellite (140).

[0009] A computer-implemented method for wireless communication includes the steps of: providing (314) a satellite-specific process message (148) from a second non-terrestrial network node (150) to at least one user equipment (100), the at least one user equipment (100) being served by the second non-terrestrial network node (150) within a second coverage area (C2), the satellite-specific process message (148) being associated with a first non-terrestrial network node (140) serving a first service coverage area (C1); and re-establishing a connection with the at least one user equipment (100) within the second coverage area (C2), the at least one user equipment (100) having previously connected (202, 302) to the first non-terrestrial network node (140) within the first coverage area (C1) served by the first non-terrestrial network node (140).

[0010] In an example embodiment, a user equipment (UE) (100) for wireless communication is provided, comprising: at least one processor (410); and at least one memory (420) storing instructions that, when executed by the processor, cause the user equipment (100) to: monitor (213, 316) satellite-specific information (141) and / or satellite-specific process messages (148) provided by a second satellite (150), the satellite-specific information (141) and / or satellite-specific process messages (148) being associated with a first satellite (140) to which the user equipment (100) was previously connected (101, 202, 302); and, upon detecting the provided satellite-specific information (141) and / or satellite-specific process messages (148) associated with the first satellite (140), trigger a reconnection (214, 318) with the second satellite (150).

[0011] A second non-terrestrial network node (150) for wireless communication includes: at least one processor (410); and at least one memory (420) storing instructions that, when executed by the processor, cause the second non-terrestrial network node (150) to: provide (steps 212, 314) satellite-specific information (141) and / or satellite-specific process messages (148) to at least one user equipment (100), wherein the at least one user equipment (100) is served by the second non-terrestrial network node (150) within a second coverage area (C2), the satellite-specific information (141) and / or satellite-specific process messages (148). Associated with a first non-terrestrial network node (140) serving a first service coverage area (C1); and in a second coverage area (C2) reconnecting (318) to at least one user equipment (100) previously connected (202, 302) to the first non-terrestrial network node (140) within the first coverage area (C1) served by the first non-terrestrial network node (140).

[0012] A user equipment (UE) (100) for wireless communication includes: components for monitoring (213, 316) satellite-specific information (141) and / or satellite-specific process messages (148) provided by a second satellite (150), the satellite-specific information (141) and / or satellite-specific process messages (148) being related to a first satellite (140) to which the user equipment (100) was previously connected (202, 302); and components for triggering the restoration of connection (214, 318) with the second satellite (150) upon detecting the provided satellite-specific information (141) and / or satellite-specific process messages (148) related to the first satellite (140).

[0013] A second non-terrestrial network node (150) for wireless communication includes: components for providing (steps 212, 314) satellite-specific information (141) and / or satellite-specific process messages (148) to at least one user equipment (100), the at least one user equipment (100) being served by the second non-terrestrial network node (150) within a second coverage area (C2), the satellite-specific information (141) and / or satellite-specific process messages (148) being associated with a first non-terrestrial network node (140) serving a first service coverage area (C1); and components for re-establishing a connection with at least one user equipment (100) within the second coverage area (C2), the at least one user equipment (100) having previously connected (202, 302) to the first non-terrestrial network node (140) within the first coverage area (C1) served by the first non-terrestrial network node (140).

[0014] A computer-implemented method for wireless communication includes performing the following steps: monitoring (213, 316) by a user equipment (UE) (100) satellite-specific information (141) and / or satellite-specific process messages (148) provided by a second satellite (150), the satellite-specific information (141) and / or satellite-specific process messages (148) being related to a first satellite (140) to which the user equipment (100) was previously connected (202, 302); and triggering a restoration of connection with the second satellite (150) (214, 318) upon detecting the provided satellite-specific information (141) and / or satellite-specific process messages (148) related to the first satellite (140).

[0015] A computer-implemented method for wireless communication includes performing the following steps: providing (steps 212, 314) satellite-specific information (141) and / or satellite-specific process messages (148) to at least one user equipment (100) by a second non-terrestrial network node (150), the at least one user equipment (100) being served by the second non-terrestrial network node (150) within a second coverage area (C2), the satellite-specific information (141) and / or satellite-specific process messages (148) being associated with a first non-terrestrial network node (140) serving a first service coverage area (C1); and re-establishing a connection by the second non-terrestrial network node (150) with the at least one user equipment (100) within the second coverage area (C2), the at least one user equipment (100) having previously connected (202, 302) to the first non-terrestrial network node (140) within the first coverage area (C1) served by the first non-terrestrial network node (140).

[0016] A user equipment (UE) (100) for wireless communication includes: at least one processor (410); and at least one memory (420) storing instructions that, when executed by the processor, cause the user equipment (100) to: monitor (213) satellite-specific information (141) provided by a second satellite (150), the satellite-specific information (141) being related to a first satellite (140) to which the user equipment (100) was previously connected (202, 302); and, upon detecting the provided satellite-specific information (141) related to the first satellite (140), trigger the restoration of the connection with the second satellite (150) (214, 318).

[0017] A second non-terrestrial network node (150) for wireless communication includes: at least one processor (410); and at least one memory (420) storing instructions that, when executed by the processor, cause the second non-terrestrial network node (150) to: provide (step 212) satellite-specific information (141) to at least one user equipment (100), the at least one user equipment (100) being served by the second non-terrestrial network node (150) within a second coverage area (C2), the satellite-specific information (141) being associated with a first non-terrestrial network node (140) serving a first service coverage area (C1); and to restore a connection with the at least one user equipment (100) within the second coverage area (C2), the at least one user equipment (100) having previously connected (202, 302) to the first non-terrestrial network node (140) within the first coverage area (C1) served by the first non-terrestrial network node (140).

[0018] A user equipment (UE) (100) for wireless communication includes: a component for monitoring (213) satellite-specific information (141) provided by a second satellite (150), the satellite-specific information (141) being related to a first satellite (140) to which the user equipment (100) was previously connected (202, 302); and a component for triggering the restoration of connection (214) with the second satellite (150) upon detecting the provided satellite-specific information (141) related to the first satellite (140).

[0019] A second non-terrestrial network node (150) for wireless communication includes: components for providing (step 212) satellite-specific information (141) to at least one user equipment (100), the at least one user equipment (100) being served by the second non-terrestrial network node (150) in a second coverage area (C2), the satellite-specific information (141) being associated with a first non-terrestrial network node (140) serving a first service coverage area (C1); and components for re-establishing a connection with the at least one user equipment (100) in the second coverage area (C2), the at least one user equipment (100) having previously connected (202, 302) to the first non-terrestrial network node (140) in the first coverage area (C1) served by the first non-terrestrial network node (140).

[0020] A computer-implemented method for wireless communication includes: monitoring (213) satellite-specific information (141) provided by a second satellite (150) by a user equipment (100), the satellite-specific information (141) being related to a first satellite (140) to which the user equipment (100) was previously connected (202, 302); and triggering the restoration of connection with the second satellite (150) (214) upon detecting the provided satellite-specific information (141) related to the first satellite (140).

[0021] A computer-implemented method for wireless communication includes: providing (step 212) satellite-specific information (141) from a second non-terrestrial network node (150) to at least one user equipment (150), the at least one user equipment (150) being served by the second non-terrestrial network node (150) within a second coverage area (C2), the satellite-specific information (141) being associated with a first non-terrestrial network node (140) serving a first service coverage area (C1); and re-establishing a connection with at least one user equipment (100) within the second coverage area (C2), the at least one user equipment (100) having previously connected (202, 302) to the first non-terrestrial network node (140) within the first coverage area (C1) served by the first non-terrestrial network node (140). Attached Figure Description

[0022] Therefore, certain exemplary embodiments of this disclosure have been described in general terms, and reference will be made below to the accompanying drawings, which are not necessarily drawn to scale, and wherein: Figure 1 It is a system diagram depicting the store-and-forward (S&F) operation scheme; Figure 2 This is a block diagram illustrating an exemplary embodiment solution for restoring service link connectivity between satellites during store-and-forward (S&F) operations; Figure 3 This is a block diagram illustrating another exemplary embodiment solution for restoring service link connectivity between satellites during store-and-forward (S&F) operations; Figure 4 This is a system diagram illustrating components configured to perform the described steps or functions by a user equipment (UE) or a non-terrestrial network node (NW).

[0023] Figure 5 Deployable according to exemplary embodiments of this disclosure Figure 4 A block diagram illustrating an example of a communication system. Detailed Implementation

[0024] Some embodiments of the present disclosure will now be described more fully below with reference to the accompanying drawings, which illustrate some, but not all, of the embodiments. In fact, various embodiments may be embodied in many different forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided so that the disclosure will satisfy applicable legal requirements. The same reference numerals throughout refer to the same elements. As used herein, the terms “data,” “content,” “information,” and similar terms are used interchangeably to refer to data capable of being transmitted, received, and / or stored according to embodiments of the present disclosure. Therefore, the use of any such terms should not be construed as limiting the spirit and scope of the embodiments of the present disclosure.

[0025] Additionally, as used herein, the term "circuit" means (a) a hardware circuit implementation (e.g., an implementation in analog and / or digital circuitry); (b) a combination of a circuit and (multiple) computer program products, including software and / or firmware instructions stored on one or more computer-readable storage media, which work together to enable a device to perform one or more functions described herein; and (c) a circuit, such as (multiple) microprocessors or portions thereof, which require software or firmware to operate even if the software or firmware is not physically present. This definition of "circuit" applies to all uses of the term herein, including in any claim. As another example, as used herein, the term "circuit" also includes an implementation comprising one or more processors and / or portions thereof, along with accompanying software and / or firmware. As another example, as used herein, the term "circuit" also includes, for example, baseband integrated circuits or application processor integrated circuits for mobile phones, or similar integrated circuits in servers, cellular network devices, other network devices (such as core network devices), field-programmable gate arrays, and / or other computing devices.

[0026] As used herein, the term "computer-readable medium" refers to non-transitory storage hardware, non-transitory storage device, or non-transitory computer system memory that can be accessed by a controller, microcontroller, computing system, or module of a computing system to encode computer-executable instructions or software programs thereon. A non-transitory "computer-readable medium" can be accessed by a computing system or module of a computing system to retrieve and / or execute computer-executable instructions or software programs encoded on the medium. Examples of non-transitory computer-readable media may include, but are not limited to, one or more types of hardware memory, non-transitory tangible media (e.g., one or more magnetic disks, one or more optical disks, one or more Universal Synchronous Bus (USB) flash drives), computer system memory, or random access memory (such as dynamic random access memory (DRAM), static random access memory (SRAM), extended data output random access memory (EDO RAM), etc.).

[0027] The terms "user equipment," "terminal equipment," and "mobile terminal" are used interchangeably with equivalent meanings. The terms "non-terrestrial network node," "satellite," "network node," "gNB," and "base station" are used interchangeably with their equivalent meanings. The terms "core network," "Mobility Management Entity (MME)," "Mobility Management Function (AMF)," and "ground station" are used interchangeably with equivalent meanings. The terms "non-terrestrial network node," "satellite," or "network node" are used interchangeably with equivalent meanings. The terms "new satellite" and "second satellite" are used interchangeably with equivalent meanings. The terms "previous satellite" and "first satellite" are used interchangeably with their equivalent meanings.

[0028] like Figure 1 As shown, the store-and-forward satellite (S&F) operation provides communication services to the user equipment (UE) (100) during time periods (T1, T2, T3) and / or geographical areas (Rennes, Le Mans, Orleans) (102 to 106), wherein the first serving satellite (140) is simultaneously connected to the terrestrial network (120A or 120B) without via feeder links (105, 107) or inter-satellite links (ISL).

[0029] The store-and-forward (S&F) scheme can rely on a regenerative architecture, where the RAN will be housed in at least one first satellite (140a to 140n). In the S&F scheme, the MME (or AMF for 5GS-type deployments) (120) at the first satellite (140) can be solely responsible for providing the store-and-forward features. The MME in the first satellite (140) can... Figure 1 The designation is MME-NT-1 (non-terrestrial). Assume time T1 is between 10:00 and 10:20, T2 is between 10:40 and 11:00, and T3 is between 11:20 and 11:40. Multiple second satellites (150a to 150x) can have ground station (120A) coverage when hovering over Rennes (102) and Orleans (106), but not when crossing Le Mans (104).

[0030] At time T1, at least one first satellite (140) can cover Le Mans (104). At T2, the first satellite (140) can move to provide coverage to Orléans (106), and the second satellite (150) can cover Rennes (102) where ground stations are deployed. The two ground stations deployed in Orléans and Rennes are connected to the same core network (120).

[0031] At time T3, the second satellite (150) can move to provide coverage to Le Mans where the UE (100) is located. Therefore, the service link (101, 103) (i.e., the connection between the first satellite 140 or the second satellite 150 and the UE (100)) and the feeder link (105, 107) (i.e., the connection between the first satellite (140) or the second satellite (150) and the gateway or core network (120)) are not available simultaneously.

[0032] refer to Figure 2 and Figure 3 At time T1, when the serving link (101) is available, the UE (100) can send an uplink control plane (UL CP) message or UP data to the first satellite (140) (see steps 202, 302). However, the UE (100) cannot immediately obtain a downlink (DL) response because the feeder link (105) between the same satellite (140) and the ground station (120A, 120B) may not be available simultaneously. The UE (100) pause (see steps 204, 304) and recovery process (steps 216, 318) can be performed before the serving link becomes unavailable and after the serving link becomes available again. When the UE needs to restore the connection, it can initiate a UE-specific paging procedure to trigger UE (100) recovery or rely on UE autonomous recovery initiated by the RACH procedure whenever the serving link (103) becomes available again.

[0033] However, these options have the following problems: (1) If the UE (100) autonomously restores the RRC connection whenever the serving link (103) becomes available again with the (new) second satellite (150) in a multi-satellite scenario, it is possible that the DL response message or DL ​​data associated with the UE (100) (step 208) has not yet been received and stored in the second satellite (150) (e.g., if the previous satellite (140) has not yet connected to the ground station (120B) but has not yet forwarded the UE's (100) UL data (from step 206) to the ground station (120B), or the second satellite (150) may not yet have connected to the ground station (120B) to obtain the UE's (100) DL response data (see step 208)). In this case, the UE (100) may unnecessarily restore the connection (step 216), thus potentially wasting the UE's (100) power consumption and the radio resources / capacity of the serving link (103) used to perform the connection restoration process (step 216).

[0034] (2) Alternatively, if UE (100) restores connection (step 318) based on paging (step 314) from the current second satellite (150), there may be a large number of other UEs (100a…100x) that have already sent their UL data to the previous first satellite (140) and therefore have stored DL data in the current second satellite (150), which may result in a large number of paging messages (148) being sent individually to other UEs (100a…100x) (step 314). This may lead to potential resource congestion due to the delivery of a large number of individual paging messages (148) to other UEs (100a…100x), which may also lead to delays in the delivery of individual paging messages (148).

[0035] (3) In any of the above scenarios, if a large number of UEs (100a…100x) simultaneously initiate random access (RA) procedures to restore their connections (steps 216, 318) when the serving link (101, 103) becomes available in a given coverage area (C1), it may lead to congestion of PRACH resources (e.g., in terms of RACH preambles and / or resources for sending RACH preambles that are prone to contention or conflict). This may in turn degrade the performance of RACH and UE recovery procedures (steps 216, 318). Such congestion / capacity issues may occur in deployments of Earth-fixed cell types, where satellite service becomes available in a large area (e.g., a cell with a diameter of 50 km) at a known time. Time may be based on satellite-assisted information (see SIB32 for discontinuous coverage, which defines t-service as the time when EFC is available in a given area).

[0036] This disclosure proposes a mechanism (Solution #1 and Solution #2) for more efficient and reliable triggering of a UE (100) to restore connectivity when a service link (103) to a new satellite (150) becomes available again. More specifically, this disclosure proposes satellite-specific information and / or satellite-specific process messages corresponding to the satellite (140) to which the UE (100) is connected, and the transmission of UL CP messages or UL data when a service link (101) to the satellite (140) becomes available. That is, the UE (100a…100x) can be triggered to restore connectivity to a new satellite (150) based on satellite-specific information (141) / satellite-specific process messages (148) associated with the previous satellite (140). Detailed proposals include a first satellite (140) representing the previous satellite to which the UE (100) was previously connected, and a second satellite (150) representing the new satellite to which the UE (100) is triggered to restore connectivity.

[0037] In Solution #1 (Explicit Approach): For example, when satellite (150) provides a service link (103) in at least part of the coverage area (C1) where satellite (140) has already provided a service link (101) to the UE, satellite (140) uses a system information block (SIB) provided by the cell to broadcast satellite (140) specific information (e.g., satellite ID or (multiple) cell IDs provided by satellite (140)). In this context, satellite (150) is a satellite that has stored DL CP response messages or user plane (UP) data to be sent to the UE (100, 100a to 100x).

[0038] In order to facilitate the second satellite (150) to broadcast specific information (141) of the first satellite (140) to the UE (100) when the second satellite (150) provides a service link (103) to the UE (100), when the ground station (120A, 120B) core network (120) sends a DL CP response message or UP data to the second satellite (150), the ground station (120A, 120B) / core network (120) should provide the first satellite specific information (141) to the second satellite (150) (step 208).

[0039] In addition to the first satellite (140) specific information (such as the satellite ID or (multiple) cell IDs of the first satellite (140)) already provided in the first coverage area (C1) where the UE (100a…100x) is located, verification information (144) associated with the first satellite (140) specific information may also be provided. The verification information (144) may be in the form of a time period, for example, the satellite (140) specific information is valid during the time period (T1, T2); or in the form of a coverage area, for example, the first satellite (140) specific information is valid when the second satellite (150) covers one or more coverage areas (C1, C2); or in the form of a combination of time and coverage area, for example, the satellite specific information (141) is valid for X time units after the second satellite (150) arrives at the first coverage area (C1).

[0040] The second satellite (150) broadcasts the first satellite (140) specific information (141) to the UE (100) via the service link (103) based on the first satellite specific information (141) and associated verification information (144) during the verification period (144) and / or verification area (C1, C2).

[0041] During time period T3, when UE (100) detects the availability of a serving link (103), UE (100) can read the broadcast SIB provided by the cell from the new satellite (150). If UE (100) recognizes satellite (140) specific information (e.g., the cell ID or satellite ID of satellite 140), UE (100) autonomously initiates an RRC recovery procedure to the new satellite (150) using the recovery ID that was previously configured for UE by the satellite (140) during the UE pause procedure. In this case, even if UE (100) detects the availability of a serving link from another satellite (150x) before detecting the availability of a serving link from satellite (150), UE (100) will not restore the connection to the other satellite (e.g., 150x) because the satellite (140) specific information is not provided by the other satellite. In this way, unnecessary autonomous UE recovery to connections to unrelated satellites (150x) can be avoided. When the UE (100) expects DL CP response messages / UP data in S&F mode, the solution also reduces or even eliminates the overhead of the paging process recovered via the autonomous UE.

[0042] In Solution #2 (Implicit Method): Satellite (140) specific paging information (143) can be configured to the UE (100) so that the second satellite (150) can use a common paging message to page UEs (100.100a…100x) previously connected to the first satellite (140) (142, step 314). The first satellite (140) specific paging information (143) may include a first satellite (140) specific DRX configuration and / or a first satellite (140) specific paging ID. The first satellite (140) specific paging information can be configured to the UE (100) by the first satellite (140) when the first satellite (140) suspends the UE (100). Alternatively, the first satellite (140) specific paging information (143) can be provided by the new satellite (150) in the system information. When a new satellite (150) has stored DL CP response messages / UP data of UEs that have previously been connected to the satellite (140), the new satellite (150) will use satellite (140) specific paging information to derive paging timing (PO) to page the group of these UEs, instead of pageing each UE individually.

[0043] If satellite-specific paging information (143) is configured to the UE by the second satellite (150) to facilitate the satellite (150) in identifying which satellite-specific paging information should be used to page the group of UEs (100a…100x), then when the ground station (120A, 120B) sends a DL CP response message or UP data to the second satellite (150), the first satellite-specific paging information (143) should be provided to the second satellite (150) from the ground station (120A, 120B) or the core network (120).

[0044] In addition to the first satellite-specific paging information (143), verification information (144) associated with the first satellite-specific paging information should also be provided. The verification information (144) may be in the form of a time period (T), for example, the satellite (140) specific paging information is valid during the time period (T1, T2); or a coverage area (C), for example, the satellite (140) specific paging information (143) is valid when the satellite (150) covers one or more areas (C1, C2); or a combination of time (T) and coverage area (C), for example, the satellite (140) specific paging information may be valid for X time units after the satellite (150) arrives at C1.

[0045] If the first satellite-specific paging information (143) is configured and broadcast by the second satellite (150), the second satellite (150) shall be configured with the same type of authentication information (144) as described above for broadcasting the first satellite-specific paging information (143) and paging the UE using the first satellite-specific paging information (143) based on the authentication information (144).

[0046] In this option, if the second satellite (150) broadcasts a first satellite-specific paging message (143) for multiple first satellites (e.g., satellites 140a, ... 140n), and the UE (100) has previously been connected to more than one of the multiple satellites (140a... 140n), then the UE (100) may select one of the first satellite-specific paging messages (143) to derive a paging opportunity (PO) (145a... 145n) for paging monitoring.

[0047] Based on the first satellite specific paging information (143) and the associated verification information (144), the second satellite (150) triggers a first satellite (140) specific group paging message (148) at the derived PO (145a…145n) to the UE (100, 100a…100x) that has previously been connected to the first satellite (140).

[0048] UEs (100, 100a…100x) that have previously been connected to the first satellite (140) monitor for paging messages at the PO derived from the configured satellite (140)-specific paging information when they detect the availability of the service link (103). If the UE receives the paging message based on the satellite (140)-specific paging information, it triggers the UE to restore its connection to the satellite (150).

[0049] Since the first satellite (140) specific paging message (143) targets a group of UEs that have previously connected to the satellite (140), the group paging message can trigger all relevant UEs to simultaneously restore their connections by initiating an RA procedure, which may lead to PRACH resource congestion. To reduce PRACH resource congestion, the satellite-specific paging message may include multiple paging IDs, and each paging ID is configured for a subgroup (100a…100g) of UEs that were previously connected to the satellite (140). Therefore, different subsets of UEs are paged at corresponding different POs (145a…145n), and then the UEs are triggered to initiate an RA procedure at corresponding different times at different POs (145a…145f).

[0050] When multiple paging IDs are configured for different UE subgroups, the group paging message (148) may not include any content or may include a satellite (140) ID or a subgroup ID. Alternatively, the group paging message (148) may include a list of UE IDs (e.g., recovery IDs) or a range of UE IDs. In this case, the periodic PO is derived from a single paging ID. Multiple different paging messages are transmitted in different consecutive POs, and each paging message may include a different set of UE ID lists or a range of UE IDs. In this way, the group of UEs (100a…100x) is paged at different POs (145a…145n) and is also triggered to initiate a RA procedure at different times.

[0051] refer to Figure 2During time period T1, the non-terrestrial network (NTN) supporting store-and-forward (S&F) mode includes a satellite (140). When a feeder link (105) becomes available between the satellite (140) and ground stations (120A, 120B) during time period T2, the satellite (140) stores the UE's UL data and forwards the UE's UL data to the ground station. Upon receiving the forwarded UL data from the UE and based on satellite context information (e.g., the satellite's orbit) and optional UE context information (e.g., the UE's location, mobility status, trajectory information, etc.), the ground station can identify the next satellite (i.e., satellite (150) in our example) that will provide a service link (103) for the coverage area already provided by the satellite (140) and / or the location area of ​​a UE previously connected to the satellite (140). The identification of the satellite (150) is implemented by the ground station. Possible information that the ground station may use may include the time period (e.g., T2) of the feeder link availability (e.g., 105, 107) between each satellite (140, 150) and the ground station (120A, 120B), the time period (e.g., T1, T3) of the service link availability (e.g., 101, 103) between each satellite and a fixed UE (100) or an area in the earth, and the time period (e.g., T1, T3) of the service link availability (e.g., 101, 103) between one or more satellites (140, 140a, ... 140n, 150, 150a, ... 150x) and a mobile UE (140...).

[0052] During time period T2, the feeder link (107) also becomes available between the ground station (120A) and the identified satellite (150), and the ground station (120A) forwards the UE's DL data along with associated first satellite (140) specific information (141) (e.g., cell ID or satellite ID) and authentication information (144) to the satellite (150). This allows the second satellite (150) to broadcast the first satellite (140) specific information (141) in the SIB based on the authentication information (144) received from the ground station (120A) during time period T3 when the second satellite (150) provides the service link to the UE (100).

[0053] Since the first satellite (140) specific information (141) broadcast by the second satellite (150) can trigger (see step 214) all relevant UEs (140, 140a, ...) to simultaneously restore their connections by initiating a RA procedure, it may lead to PRACH resource congestion / conflict. In order to reduce PRACH resource congestion / conflict, the UE (100) can be configured with (multiple) PRACH timings associated with or derived from the recovery ID, so that other different UEs (140a, ... 140n) with different recovery IDs can initiate a RA procedure at different PRACH timings (145a, ...) after detecting the first satellite (140) specific information (141).

[0054] refer to Figure 3 During time period T1, as different implementation options, the first satellite (140) specific paging information (143) can be dynamically determined and configured by the satellite (140), or statically or semi-statically configured by the O&M. In the latter case, the ground station and the second satellite (150) can also obtain the satellite (140) specific paging information from the O&M, making the information from the satellite (140) to the ground station and from the ground station to the satellite (150) optional. However, during time period T2, when the ground station sends DL data to the satellite (150), it should at least provide the satellite (150) with an indication of the association between the DL data and the satellite (140) specific paging information, so that the satellite (150) knows which satellite-specific paging information (143) should be used to page the UE group (140, 140a…) to trigger the UE to resume forwarding the stored DL data.

[0055] During time period T2, after forwarding UL data from satellite (140) to those UEs (140, 140a…) previously connected to satellite (140), the ground station (120) can identify how many UEs have corresponding DL data to be sent to satellite (150). Based on the number of UEs with DL data to be sent to satellite (150) and the total number of UEs previously connected to satellite (140), the core network (120) (or MME / AMF) can also determine whether to enable satellite (140) specific paging or UE-specific paging. Alternatively, during time period T3, the second satellite (150) can determine whether to enable satellite (140) specific paging or UE-specific paging based on the number of UEs with DL data received from the ground station and associated with the first satellite (140). If there are many UEs for whom DL data is not yet available, the decision made by the ground station or satellite (150) can take into account a trade-off between the paging load introduced by individual paging and the recovery of faulty UEs using satellite-specific public paging. To further reduce erroneous UE recovery even when using satellite-specific public paging messages (142, step 314), the satellite-specific paging message (148) may also include a list of UE IDs (e.g., using recovery IDs) to prevent unrelated UEs from recovering to the satellite (150) connection. If the UE ID list is long, paging the group of UEs at different POs may also be applied to make it possible to include a shorter UE ID list in the satellite-specific public paging message (142).

[0056] In either solution, if the satellite (150) identifies that the UE has not restored connection during the time period and / or area associated with the authentication information, and the stored DL CP response message / UP data is stored in the satellite (150) for the UE, the satellite (150) may initiate a UE-specific paging procedure to page the UE individually during an extended time period and / or area, which may be configured by O&M to the satellite (150) or provided from the ground station. This is used to better serve the mobile UE if it moves out of the expected coverage area estimated by the ground station. If the UE has not restored connection to the satellite (150) during the extended time period and / or area, the satellite (150) may notify the ground station upon its next connection. The ground station may configure the satellite (150) to either retain the UE's context and data or release them.

[0057] Figure 2 and Figure 3The details present some solutions for a more efficient and reliable method of triggering the UE (100) to restore connection (101) (steps 202 to 216 or steps 302 to 316) when the service link (103) with the new satellite (150) becomes available again. For example, during time period T1, the service link (101) connection with the first satellite (140) may be available in the first coverage area (C1). In step 202, the UE (100) may send a UL CP message or UL data to the first satellite (140). In one example, based on satellite-specific information (141) / satellite-specific process message (148) associated with the first satellite (140), at least one of several other UEs (100a…100x) may be triggered to restore connection with the UE (100) together (see step 214 or step 318) to restore connection to the new second satellite (150) at time T3 (step 214 or 318).

[0058] In one example, prior to the pause in step 204, the UE (100) can obtain satellite-specific information (141) related to the first satellite (140) from system information (such as satellite ID or (multiple) cell IDs) broadcast by the first satellite (140). In another example, prior to the pause in step 304, the UE (100) can be configured to monitor at least one satellite-specific paging message (143) for monitoring satellite-specific process messages, such as a public paging message (142, 314) related to the previous first satellite (140).

[0059] During time T2, the first satellite (140) can move to another region 106 (e.g., Orleans), and the second satellite (150) can move within the Rennes region (108) to serve the region where ground stations are deployed.

[0060] During time T2, the first satellite (140) can establish a feeder link (105) with the core network (120) via a ground station (120B) to forward the UE's UL CP message or UP data (in step 206) and optional first satellite-specific information (141) including the satellite ID or (multiple) cell IDs to the core network (120). Alternatively, the first satellite (140) can establish a feeder link 105 with the core network (120) via a ground station (120B) to forward the UE's UL CP message or UP data (in step 306) and optional first satellite-specific paging information (143) to the core network (120).

[0061] During time T2, the second satellite (150) can also establish a feeder link (107) with the core network (120) via the ground station (120A), and receive downlink (DL) data for the UE (100) from the core network (120) in step 208 or step 308. Furthermore, during time T2, the second satellite (150) in step 210 can receive first satellite-specific information (141) from the core network (120), which includes a satellite ID or (multiple) cell IDs and authentication information (144) configured for the UE (100). Alternatively, in step 308, the second satellite (150) can receive a first satellite-specific process message (148) from the core network (120), which optionally includes first satellite-specific paging information (143) and authentication information (144) associated with the first satellite-specific process message (148).

[0062] During time T3, the service link (103) may be provided by the second satellite (150) to the Le Mans area where the UE (100) is located. In step 212, the UE (100) may receive a broadcast from the second satellite (150), namely a System Information Block (SIB) (141-1) message containing first satellite-specific information (141), including a satellite ID or (multiple) cell IDs. Alternatively, in step (314), the UE (100) may receive at least one first satellite-specific process message (148) associated with the first satellite (140) transmitted by the second satellite (150).

[0063] In one example, the UE (100) may monitor (see step 213) satellite-specific information (141), or in another example, the UE (100) may monitor (see step 316) at least one public paging message (142 at step 314) for paging multiple other user equipment (100a, ...x) previously connected to the first satellite (140) in the first service coverage area (101) from the second satellite (150) serving the second coverage area (C2).

[0064] In order to monitor at least one public paging message (142 at step 314), the UE (100) is configured with first satellite-specific paging information to derive PO.

[0065] The UE (100) may trigger the restoration of the connection between the second satellite (150) and the user equipment (100) in the second coverage area (C2) based on the detection of satellite-specific information (141) and / or satellite-specific process messages (148) related to the first satellite (140) from the second satellite (150) (in step 214 or step 318).

[0066] Figure 4 and Figure 5 Examples of devices are depicted that can be configured to function as user equipment (100) or as any of the non-terrestrial network nodes (e.g., satellites 140 and 150). Figure 4 As shown, the device includes processing circuitry 410, memory 420, and communication interface 260, associated with or communicating with them. The processing circuitry (410) may communicate with memory device 440 via a bus for transferring information between components of the device. The memory device may be non-transitory and may include, for example, one or more volatile and / or non-volatile memories. In other words, for example, the memory device may be an electronic storage device (e.g., a computer-readable storage medium) containing gates configured to store data (e.g., bits) that can be retrieved by a machine (e.g., a computing device such as the processing circuitry). The memory device may be configured to store information, data, content, applications, instructions, etc., for enabling the device to perform various functions according to exemplary embodiments of this disclosure. For example, the memory device may be configured to buffer input data for processing by the processing circuitry. Additionally or alternatively, the memory device may be configured to store instructions for execution by the processing circuitry.

[0067] In some embodiments, the device (100) may be embodied in various computing devices as described above. However, in some embodiments, the device may be embodied as a chip or chipset. In other words, the device may include one or more physical packages (e.g., chips) that include materials, components, and / or wires on structural components (e.g., substrates). The structural components may provide physical strength, size savings, and / or electrical interaction constraints for the component circuitry included thereon. Thus, in some cases, the device may be configured to implement embodiments on a single chip or as a single “system-on-a-chip.” Thus, in some cases, a chip or chipset may constitute means for performing one or more operations to provide the functionality described herein.

[0068] The processing circuitry (410) (also referred to as a processor) can be embodied in a variety of different ways. For example, the processing circuitry can be embodied as one or more hardware processing units among various hardware processing units, such as coprocessors, microprocessors, controllers, digital signal processors (DSPs), processing elements with or without an accompanying DSP, or various other circuits including integrated circuits, such as, for example, ASICs (Application-Specific Integrated Circuits), FPGAs (Field-Programmable Gate Arrays), microcontroller units (MCUs), hardware accelerators, dedicated computer chips, etc. Therefore, in some embodiments, the processing circuitry may include one or more processing cores configured to execute independently. Multi-core processing circuitry can implement multiple processing within a single physical package. Additionally or alternatively, the processing circuitry may include one or more processors configured in series via a bus to enable independent execution of instructions, pipelines, and / or multiple threads.

[0069] In an example embodiment, the processing circuitry (410) may be configured to execute instructions stored in a memory device (420) or otherwise accessible to the processing circuitry. Alternatively or otherwise, the processing circuitry may be configured to perform hard-coded functions. Thus, whether configured by hardware or software methods or a combination thereof, the processing circuitry may represent an entity (e.g., physically embodied in circuitry) capable of performing operations according to embodiments of this disclosure when configured accordingly. Thus, for example, when the processing circuitry is embodied as an ASIC, FPGA, etc., the processing circuitry may be hardware specifically configured to perform the operations described herein. Alternatively, as another example, when the processing circuitry is embodied as an executor of instructions, the instructions may specifically configure the processor to perform the algorithms and / or operations described herein when executing the instructions. However, in some cases, the processing circuitry may be a processor of a particular device (e.g., an image or video processing system) configured to further configure the processing circuitry to employ embodiments via instructions for performing the algorithms and / or operations described herein. The processing circuitry may include a clock, an arithmetic logic unit (ALU), and logic gates configured to support the operations of the processing circuitry.

[0070] The communication interface (440) can be any component, such as a device or circuit embodied in hardware or a combination of hardware and software, configured to receive and / or transmit data including media content in the form of video or image files, one or more audio tracks, etc. In this regard, the communication interface may include, for example, an antenna (or multiple antennas) and supporting hardware and / or software for enabling communication with a wireless communication network. Additionally or alternatively, the communication interface may include circuitry for interacting with the antenna(s) to transmit signals via or process signals received via the antenna(s). In some environments, the communication interface may alternatively or also support wired communication. Thus, for example, the communication interface may include a communication modem and / or other hardware / software for supporting communication via cable, Digital Subscriber Line (DSL), Universal Serial Bus (USB), or other mechanisms.

[0071] refer to Figure 3-4 An example embodiment of a user equipment (UE) (100) for wireless communication is disclosed, comprising: at least one processor (410); and at least one memory (420) storing instructions which, when executed by the processor, cause the user equipment (100) to perform: monitoring (316) a satellite-specific process message (148) provided by a second satellite (150), satellite-specific information (141) and / or the satellite-specific process message (148) being associated with a first satellite (140) to which the user equipment (100) was previously connected; and triggering the restoration of connection with the second satellite (150) (318) upon detection of the provided satellite-specific process message (148) associated with the first satellite (140).

[0072] Another example embodiment for a user equipment (100) is disclosed, wherein the user equipment (100) is at least one or a combination of the following: a terrestrial or non-terrestrial user equipment; a user equipment among a plurality of other user equipment (100a…100x) in a first coverage area (C1) previously served by a first satellite (140); and a user equipment among a plurality of other user equipment (100a…100x) in a second coverage area (C2) to be connected to a second satellite (150), wherein the first coverage area (C1) and the second coverage area (C2) at least partially overlap for providing a service link (101, 103) to the user equipment (100).

[0073] Another example embodiment for user equipment (100) is disclosed, wherein monitored satellite-specific information (141) and / or satellite-specific process messages (148) received from a second satellite (150) are provided by the core network (120) or ground stations (120a, 120b) (210, 310).

[0074] Another example embodiment of the user equipment (100) is disclosed, wherein a first satellite (140) is one of a plurality of other first satellites (140a...140n), and / or a second satellite (150) is one of a plurality of other second satellites (150a...150x) to provide corresponding service links to a plurality of other user equipments (100a,...100x) within a first coverage area (C1) and / or a second coverage area (C2), respectively.

[0075] Another example embodiment for user equipment (100) is disclosed, wherein a satellite-specific process message (148) associated with a first satellite (140) includes at least one first satellite-specific public paging message (142) transmitted by a second satellite to page multiple other user equipment (100a, ... 100x) previously connected to the first satellite (140), and at least one first satellite-specific public paging message (142) is associated with the first satellite (140).

[0076] Another example embodiment for a user equipment (100) is disclosed, wherein the user equipment receives satellite-specific paging information (143) to derive at least one paging opportunity (PO) (145) to monitor at least one first satellite-specific public paging message (142) associated with the first satellite (140).

[0077] Another example embodiment for a user equipment (100) is disclosed, wherein the satellite-specific paging information (143) includes at least one or a combination of the following: a satellite-specific DRX configuration and / or a satellite-specific paging ID, which is configured to be provided to the user equipment when the UE is suspended by a first satellite (140) or when provided by a second satellite (150); and authentication information (144) configured to be used for at least one of: broadcasting at least one of the satellite-specific paging information (143), or using the satellite-specific paging information (143) to page multiple other UEs (100a…100x) based on the authentication information (144).

[0078] Another example embodiment of the user equipment (100) is disclosed, wherein when the second satellite (150) has stored downlink (DL) data of UEs (100, 100a…100x) that have previously been connected to the first satellite (140), the second satellite (150) will use satellite-specific paging information (143) to derive at least one paging opportunity (PO) (145) to page the group of UEs (100, 100a…100x), instead of pageing each individual UE.

[0079] Another example embodiment for user equipment (100) is disclosed, wherein when the core network (120) or ground station (120b) sends downlink (DL) data to the second satellite (150), the second satellite (150) obtains satellite-specific paging information (143) from the core network (120) or ground station (120A, 120B).

[0080] Another example embodiment for a user equipment (100) is disclosed, wherein the satellite-specific paging information (143) further includes verification information (144) which is used for at least one of: broadcasting the satellite-specific paging information (143), or using the satellite-specific paging information (143) to page multiple other UEs (100a…100x) based on the verification information (144).

[0081] Another example embodiment for a user equipment (100) is disclosed, wherein verification information (144) associated with satellite-specific paging information (143) is provided in the form of one or a combination of the following: in the form of a time period (T1, T2) during which the satellite-specific paging information (143) is valid; or in the form of one or more second coverage areas (C2) in which the satellite-specific paging information (143) is valid when a second satellite (150) covers one or more second coverage areas (C2).

[0082] Another example embodiment for a user equipment (100) is disclosed, wherein when a second satellite 150 broadcasts satellite-specific paging information (143) for a plurality of first satellites (140a…140n) and the UE (100) has connected to more than one of the plurality of first satellites (140a…140n), the UE is configured to select at least one of the satellite-specific paging information (143) to derive at least one paging opportunity (PO) (145a…145n) for paging monitoring.

[0083] Another example embodiment for a user equipment (100) is disclosed, wherein the UE is configured to perform at least one or both of the following: when the availability of a serving link (103) is detected, monitor satellite-specific paging information (143) at at least one PO (145) derived from the configured satellite-specific paging information (143); or when a satellite-specific public paging message (142) is received, re-establish a connection (101) with a second satellite (150).

[0084] Another example embodiment for a user equipment (100) is disclosed, wherein: a satellite-specific public paging message (142) includes a plurality of paging IDs, wherein each paging ID is configured to a subgroup (100c…100f) of other UEs previously connected to the first satellite 140; and / or different subgroups (100a…100c, 100g…j, 100k…100m) of other UEs are group-paging at different paging times (PO) (145a…145n) to be triggered to initiate a random access (RA) procedure at different times.

[0085] Another example embodiment for user equipment (100) is disclosed, wherein the satellite-specific public paging message (142) is one of the following: excluding any content; or including the satellite ID or subgroup ID of the first satellite (140) when multiple paging IDs are respectively configured to different subgroups (100a…100c, 100g…j, 100k…100m) of other UEs; or including at least one of the following: a list of UE IDs, a list of recovery IDs, or a range of UE IDs.

[0086] Another example embodiment for a user equipment (100) is disclosed, wherein a plurality of first satellite-specific public paging messages (142) transmitted in different POs (145a…145n) are derived by a single paging ID, wherein each of the plurality of satellite-specific public paging messages (142) includes a different set of UE ID lists or UE ID ranges, such that subgroups (100c…100f) of other UEs paged at corresponding different POs (145c…145f) are also triggered to initiate random access (RA) procedures at different times.

[0087] Another example embodiment of a second non-terrestrial network node (150) for wireless communication is disclosed, the second non-terrestrial network node (150) comprising: at least one processor (410); and at least one memory (420) storing instructions that, when executed by the processor, cause the second non-terrestrial network node (150) to perform: providing (step 314) a satellite-specific process message (148, see step 314) to at least one user equipment (100), the at least one user equipment (100) being controlled by the second non-terrestrial network node. Point (150) serves within the second coverage area (C2), satellite-specific process messages (148) are associated with the first non-terrestrial network node (140), the first non-terrestrial network node (140) serves the first service coverage area (C1); and a connection is restored within the second coverage area (C2) to at least one user equipment (100), the at least one user equipment (100) previously connected (202, 302) to the first non-terrestrial network node (140) within the first coverage area (C1) served by the first non-terrestrial network node (140).

[0088] Another example embodiment for a second non-terrestrial network node (150) is disclosed, wherein the provided satellite-specific process message (148 in step 314) is provided by the core network (120) or ground station (120A, 120B) (210, 310), and the second non-terrestrial network node (150) obtains the satellite-specific paging message (148 in step 314) from the core network (120) or ground station (120A, 120B) when the core network (120) or ground station (120A, 120B) sends downlink (DL) data to the second satellite (150).

[0089] Another example embodiment for a second non-terrestrial network node (150) is disclosed, wherein at least one user equipment (100) is at least one of the following or a combination of the following: One of a plurality of other user equipments (100a…100x) that were previously connected to a first non-terrestrial network node (140) within a first coverage area (C1); or one of a plurality of other user equipments (100a…100x) that will be connected to a second non-terrestrial network node (150) within a second coverage area (C2), wherein the first coverage area (C1) and the second coverage area (C2) at least partially overlap.

[0090] Another example embodiment for a second non-terrestrial network node (150) is disclosed, wherein a satellite-specific process message (148) associated with a first non-terrestrial network node (140) includes at least one first satellite-specific public paging message (142) sent by the second non-terrestrial network node (150) and associated with the first non-terrestrial network node (140) to page a plurality of other user equipment (100a, ... x) previously connected to the first non-terrestrial network node (140).

[0091] Another example embodiment for a second non-terrestrial network node (150) is disclosed, wherein at least one first satellite-specific public paging message (142) is sent based on first non-terrestrial network node (140) specific paging information (143), the first non-terrestrial network (140) specific paging information (143) including at least one or a combination of the following: satellite-specific DRX configuration and / or satellite-specific paging ID, the satellite-specific DRX configuration and / or satellite-specific paging ID being configured to the user equipment when the UE is suspended by the first non-terrestrial network node (140) or when provided by the second non-terrestrial network node (150); and authentication information (144), the authentication information (144) being configured to: broadcast at least one of the satellite-specific paging information (143), or use the satellite-specific paging information (143) to page multiple other UEs (100a…100x) according to the authentication information (144).

[0092] Another example embodiment for a second non-terrestrial network node (150) is disclosed, wherein when the second non-terrestrial network node (150) has stored downlink (DL) data of UEs (100, 100a…100x), the second non-terrestrial network node (150) will use satellite-specific paging information (143) to derive at least one paging opportunity (PO) (145) to paging a group of UEs (100, 100a…100x) instead of paging each individual UE, multiple UEs (100, 100a…100x) previously connected to the first non-terrestrial network node (140).

[0093] Another example embodiment for a second non-terrestrial network node (150) is disclosed, wherein the second non-terrestrial network node is configured to obtain satellite-specific paging information (143) from the core network (120) or the ground station (120A, 120B) when the core network (120) or the ground station (120A, 120B) sends downlink (DL) data to the second non-terrestrial network node (150).

[0094] Another example embodiment for a second non-terrestrial network node (150) is disclosed, wherein the satellite-specific paging information (143) further includes verification information (144) which is used for at least one of: broadcasting the satellite-specific paging information (143), or using the satellite-specific paging information (143) to page multiple other UEs (100a…100x) based on the verification information (144).

[0095] Another example embodiment for a second non-terrestrial network node (150) is disclosed, wherein verification information (144) associated with satellite-specific paging information (143) is provided in the form of one or a combination of the following: in the form of a time period (T1, T2) during which the satellite-specific paging information (143) is valid; or in the form of one or more second coverage areas (C2) in which the satellite-specific paging information (143) is valid when the second satellite (150) covers one or more second coverage areas (C2).

[0096] Another example embodiment for a second non-terrestrial network node (150) is disclosed, wherein when the second non-terrestrial network node 150 broadcasts satellite-specific paging information (143) for a plurality of first non-terrestrial network nodes (140a…140n) and the UE (100) has connected to more than one of the plurality of first non-terrestrial network nodes (140a…140n), the UE is configured to select at least one of the satellite-specific paging information (143) to derive at least one paging opportunity (PO) (145) for paging monitoring.

[0097] Another example embodiment for a second non-terrestrial network node (150) is disclosed, wherein a satellite-specific public paging message (142) includes a plurality of paging IDs, wherein each paging ID is configured to a subgroup (100c…100f) of other UEs previously connected to the first satellite 140; and / or different subgroups (100a…100c, 100g…j, 100k…100m) of other UEs are paged at different paging times (PO) (150a…150x) to be triggered to initiate a random access (RA) procedure at different times.

[0098] Another example embodiment for a second non-terrestrial network node (150) is disclosed, wherein when multiple paging IDs are respectively configured to different subgroups (100a…100c, 100g…j, 100k…100m) of other UEs, the satellite-specific public paging message (142) is one of the following: excluding any content; or including the satellite ID or subgroup ID of the first non-terrestrial network node (140); or including at least one of the following: a list of UE IDs, a list of recovery IDs, or a range of UE IDs.

[0099] Another example embodiment for a second non-terrestrial network node (150) is disclosed, wherein multiple first satellite-specific public paging messages (142) sent in different POs (150a…150n) are derived from a single paging ID, wherein each of the multiple satellite-specific public paging messages (142) includes a different set of UE ID lists or UE ID ranges, such that subgroups (100c…100f) of other UEs paged at corresponding different POs (150c…150f) are also triggered to initiate random access (RA) procedures at different times.

[0100] Another example embodiment of a user equipment (UE) (100) for wireless communication is disclosed, comprising: components for monitoring (316) a satellite-specific process message (148) provided by a second satellite (150), the satellite-specific process message (148) being associated with a first satellite (140) to which the user equipment (100) was previously connected; and components for triggering the restoration of connection (318) with the second satellite (150) upon detection of the provided satellite-specific process message (148) associated with the first satellite (140).

[0101] Another example embodiment of a second non-terrestrial network node (150) for wireless communication is disclosed, comprising: components for providing (step 314) a satellite-specific process message (148) to at least one user equipment (100), the at least one user equipment (100) being served by the second non-terrestrial network node (150) in a second coverage area (C2), the satellite-specific process message (148) being associated with a first non-terrestrial network node (140) serving a first service coverage area (C1); and components for resuming connection with at least one user equipment (100) in the second coverage area (C2), the at least one user equipment (100) having previously connected (202, 302) to the first non-terrestrial network node (140) in the first coverage area (C1) served by the first non-terrestrial network node (140).

[0102] Another example embodiment of a computer-implemented method for wireless communication is disclosed, comprising the steps of: monitoring (315) by a user equipment (100) a satellite-specific process message (148) provided by a second satellite (150), the satellite-specific process message (148) being associated with a first satellite (140) to which the user equipment (100) was previously connected; and triggering a reconnection (318) with the second satellite (150) upon detection of the provided second satellite (150) and the satellite-specific process message (148) associated with the first satellite (140).

[0103] Another example embodiment of a computer-implemented method for wireless communication is disclosed, the method comprising the steps of: providing (step 314) a satellite-specific process message (148) to at least one user equipment (100) by a second non-terrestrial network node (150), the at least one user equipment (100) being served by the second non-terrestrial network node (150) in a second coverage area (C2), the satellite-specific process message (148) being associated with a first non-terrestrial network node (140), the first non-terrestrial network node (140) serving a first service coverage area (C1); and restoring the connection with the at least one user equipment (100) within the second coverage area (C2) by the second non-terrestrial network node (150), the at least one user equipment (100) having previously connected (202, 302) to the first non-terrestrial network node (140) within the first coverage area (C1) served by the first non-terrestrial network node (140).

[0104] With the help of the teachings presented in the foregoing description and the accompanying drawings, those skilled in the art to which this disclosure pertains will conceive of many modifications and other embodiments set forth herein. Therefore, it should be understood that this disclosure is not limited to the specific embodiments disclosed, and that modifications and other embodiments are intended to be included within the scope of the appended claims.

[0105] Furthermore, although the foregoing description and related figures describe exemplary embodiments in the context of certain example combinations of elements and / or functions, it should be understood that different combinations of elements and / or functions may be provided by alternative embodiments without departing from the scope of the appended claims. In this regard, for example, combinations of elements and / or functions different from those explicitly described above are also contemplated as being set forth in some of the appended claims. Although specific terminology is used herein, it is used only in a general and descriptive sense and not for limiting purposes.

Claims

1. A user equipment (UE) for wireless communication, comprising: At least one processor; as well as At least one memory, the at least one memory storing instructions that, when executed by the processor, cause the user equipment to perform: Monitor satellite-specific process messages provided by a second satellite, which are related to the first satellite to which the user equipment was previously connected; as well as Upon detecting the satellite-specific process message provided in relation to the first satellite, the connection with the second satellite is restored.

2. The user equipment according to claim 1, wherein the user equipment is at least one of the following or a combination of the following: Ground-based or non-ground-based user equipment; One of a plurality of other user equipment within a first coverage area (C1), the first coverage area previously served by the first satellite; and One of several other user equipment units within the second coverage area (C2), which will be connected to the second satellite. The first coverage area (C1) and the second coverage area (C2) overlap at least partially to provide a service link to the user equipment.

3. The user equipment according to claim 1, wherein the monitored satellite-specific process message received from the second satellite is provided by the core network or a ground station.

4. The user equipment according to any one of claims 1 to 3, wherein the first satellite is one of a plurality of other first satellites, and / or the second satellite is one of a plurality of other second satellites, to provide corresponding service links to the plurality of other user equipments respectively within the first coverage area (C1) and / or the second coverage area (C2).

5. The user equipment of claim 1, wherein the satellite-specific process message associated with the first satellite includes at least one first satellite-specific public paging message transmitted by the second satellite to page the plurality of other user equipment previously connected to the first satellite, the at least one first satellite-specific public paging message being associated with the first satellite.

6. The user equipment of claim 5, wherein the user equipment receives satellite-specific paging information to derive at least one paging opportunity (PO) to monitor the at least one first satellite-specific public paging message associated with the first satellite.

7. The user equipment of claim 6, wherein the satellite-specific paging information comprises at least one of the following or a combination of the following: Satellite-specific DRX configuration and / or satellite-specific paging ID, wherein the satellite-specific DRX configuration and / or the satellite-specific paging ID are configured to the user equipment when the UE is suspended by the first satellite or when it is provided by the second satellite; and The verification information is configured to be used for at least one of the following: broadcasting at least one of the satellite-specific paging information, or using the satellite-specific paging information to page multiple other UEs based on the verification information.

8. The user equipment according to any one of claims 4 to 7, wherein when the second satellite has stored downlink (DL) data for the plurality of UEs, the second satellite will use the satellite-specific paging information to derive the at least one paging opportunity (PO) to paging the group of UEs, rather than paging each individual UE, the plurality of UEs having previously been connected to the first satellite.

9. The user equipment according to claim 8, wherein when the core network or the ground station sends the downlink (DL) data to the second satellite, the second satellite obtains the satellite-specific paging information from the core network or the ground station.

10. The user equipment of claim 8, wherein the satellite-specific paging information further includes authentication information for at least one of: broadcasting the satellite-specific paging information, or using the satellite-specific paging information to page multiple other UEs based on the authentication information.

11. The user equipment of claim 10, wherein the authentication information associated with the satellite-specific paging information is provided in a form comprising one or a combination of the following: The satellite-specific paging information is valid during a time period (T1, T2); or In the form of one or more second coverage areas (C2), wherein the satellite-specific paging information is valid when the second satellite covers the one or more second coverage areas (C2).

12. The user equipment of claim 7, wherein when the second satellite broadcasts the satellite-specific paging information for a plurality of first satellites, and the UE is connected to more than one of the plurality of first satellites, wherein the UE is configured to select one of the at least one satellite-specific paging information to derive the at least one paging opportunity (PO) for paging monitoring.

13. The user equipment according to any one of claims 5 to 12, wherein the UE is configured to perform at least one or both of the following: Upon detecting service link availability, monitor the satellite-specific public paging message at at least one PO derived from the configured satellite-specific paging information; or Upon receiving the satellite-specific public paging message, the connection with the second satellite is restored.

14. The user equipment according to claim 13, wherein: The satellite-specific public paging message includes multiple paging IDs, each of which is configured for a subgroup of other UEs previously connected to the first satellite 140; and / or The other UEs are group-paged at different paging times (PO) to trigger the random access (RA) procedure at different times.

15. The user equipment of claim 14, wherein the satellite-specific public paging message is one of the following: No content included; or When multiple paging IDs are configured to different subgroups of other UEs, including the satellite ID or subgroup ID of the first satellite; or Includes at least one of the following: UE ID list, recovery ID list, or UE ID range.

16. The user equipment of claim 15, wherein the plurality of first satellite-specific public paging messages transmitted in different POs are derived by a single paging ID, wherein each of the plurality of satellite-specific public paging messages includes a different set of UE ID lists or UE ID ranges, such that subgroups of the other UEs paged at corresponding different POs are also triggered to initiate a random access (RA) procedure at the different times.

17. A second non-terrestrial network node for wireless communication, comprising: At least one processor; as well as At least one memory, the at least one memory storing instructions that, when executed by the processor, cause the second non-terrestrial network node to perform: Provide satellite-specific process messages to at least one user equipment, the at least one user equipment being served by a second non-terrestrial network node within a second coverage area (C2), the satellite-specific process messages being associated with a first non-terrestrial network node serving a first service coverage area (C1); as well as Restore connection to the at least one user equipment within the second coverage area (C2), the at least one user equipment previously connected to the first non-terrestrial network node within the first coverage area (C1) served by the first non-terrestrial network node.

18. The second non-terrestrial network node according to claim 17, wherein the satellite-specific process message provided is provided by the core network or the ground station, and the second non-terrestrial network node obtains the satellite-specific process message from the core network or the ground station when the core network or the ground station sends the downlink (DL) data to the second satellite.

19. The second non-terrestrial network node according to any one of claims 17 to 18, wherein the at least one user equipment is at least one or both of the following: One of a plurality of other user equipments that was previously connected to the first non-terrestrial network node within the first coverage area (C1); and One of the plurality of other user equipments, which will connect to the second non-terrestrial network node within the second coverage area (C2), wherein the first coverage area (C1) and the second coverage area (C2) at least partially overlap.

20. The second non-terrestrial network node according to any one of claims 10 to 12, wherein the satellite-specific process message associated with the first non-terrestrial network node includes at least one first satellite-specific public paging message sent by the second non-terrestrial network node to page the plurality of other user equipment previously connected to the first non-terrestrial network node, the at least one first satellite-specific public paging message being associated with the first non-terrestrial network node.

21. The second non-terrestrial network node of claim 20, wherein sending at least one first satellite-specific public paging message is based on first non-terrestrial network-specific paging information, the first non-terrestrial network node-specific paging information comprising at least one of the following or a combination of the following: Satellite-specific DRX configuration and / or satellite-specific paging ID, wherein the satellite-specific DRX configuration and / or the satellite-specific paging ID are configured to the user equipment when the UE is suspended by the first non-terrestrial network node, or when provided by the second non-terrestrial network node; and The verification information is configured to be used for at least one of the following: broadcasting at least one of the satellite-specific paging information, or using the satellite-specific paging information to page multiple other UEs based on the verification information.

22. The second non-terrestrial network node according to any one of claims 17 to 21, wherein when the second non-terrestrial network node has stored the downlink (DL) data for the plurality of UEs, the second non-terrestrial network node will use the satellite-specific paging information to derive the at least one paging opportunity (PO) to paging the group of UEs, rather than paging each individual UE, the plurality of UEs having previously been connected to the first non-terrestrial network node.

23. The second non-terrestrial network node according to claim 22 is configured to: obtain the satellite-specific paging information from the core network or the ground station when the core network or the ground station sends the downlink (DL) data to the second non-terrestrial network node.

24. The second non-terrestrial network node of claim 23, wherein the satellite-specific paging information further includes authentication information for at least one of: broadcasting the satellite-specific paging information, or using the satellite-specific paging information to page multiple other UEs based on the authentication information.

25. The second non-terrestrial network node of claim 24, wherein the verification information associated with the satellite-specific paging information is provided in a form including one or a combination of the following: The satellite-specific paging information is valid during the time period (T1, T2); or In the form of one or more second coverage areas (C2), wherein the satellite-specific paging information is valid when the second satellite covers the one or more second coverage areas (C2).

26. The second non-terrestrial network node of claim 22, wherein when the second non-terrestrial network node broadcasts the satellite-specific paging information for a plurality of first non-terrestrial network nodes, and the UE has connected to more than one of the plurality of first non-terrestrial network nodes, wherein the UE is configured to select one of the at least one satellite-specific paging information to derive the at least one paging opportunity (PO) for paging monitoring.

27. The second non-terrestrial network node according to any one of claims 22 to 26, wherein the satellite-specific public paging message includes a plurality of paging IDs, wherein, Each paging ID is configured for a subgroup of other UEs that were previously connected to the first satellite 140; and / or Page different subgroups of other UEs at different paging times (PO) to trigger random access (RA) procedures at different times.

28. The second non-terrestrial network node of claim 27, wherein the satellite-specific public paging message is one of the following: No content included; or When multiple paging IDs are configured to different subgroups of other UEs, including the satellite ID or subgroup ID of the first non-terrestrial network node; or Includes at least one of the following: UE ID list, recovery ID list, or UE ID range.

29. The user equipment of claim 15, wherein the plurality of first satellite-specific public paging messages transmitted in different POs are derived by a single paging ID, wherein each of the plurality of satellite-specific public paging messages includes a different set of UE ID lists or UE ID ranges, such that subgroups of the other UEs paged at corresponding different POs are also triggered to initiate a random access (RA) procedure at the different times.

30. A user equipment (UE) for wireless communication, comprising: Components for monitoring satellite-specific process messages provided by a second satellite, the satellite-specific process messages being related to a first satellite to which the user equipment was previously connected; as well as A component for triggering the restoration of connection with the second satellite upon detection of a satellite-specific process message provided in relation to the first satellite.

31. A second non-terrestrial network node for wireless communication, comprising: Components for providing satellite-specific process messages to at least one user equipment, the at least one user equipment being served by a second non-terrestrial network node within a second coverage area (C2), the satellite-specific process messages being associated with a first non-terrestrial network node serving a first service coverage area (C1); as well as Components for resuming connection with the at least one user equipment within the second coverage area (C2), the at least one user equipment previously connected to the first non-terrestrial network node within the first coverage area (C1) served by the first non-terrestrial network node.

32. A computer-implemented method for wireless communication, comprising: The user equipment monitors satellite-specific process messages provided by a second satellite, which are related to a first satellite to which the user equipment was previously connected. as well as Upon detecting the provided satellite-specific process message related to the first satellite, the connection with the second satellite is restored.

33. A computer-implemented method for wireless communication, comprising: A satellite-specific process message is provided by a second non-terrestrial network node to at least one user equipment, the at least one user equipment being served by the second non-terrestrial network node within a second coverage area (C2), the satellite-specific process message being associated with a first non-terrestrial network node serving a first service coverage area (C1); and The connection to the at least one user equipment is restored by the second non-terrestrial network node within the second coverage area (C2), the at least one user equipment previously connected to the first non-terrestrial network node in the first coverage area (C1) served by the first non-terrestrial network node.

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