Timing advance reporting

Abstract

The embodiment of the invention relates to a method, equipment and device for timing advance reporting and a computer readable storage medium. In one method, a first apparatus determines a predicted timing advance associated with a target non-terrestrial network device prior to transitioning a connection from a source non-terrestrial network device to the target non-terrestrial network device. A source non-terrestrial network device serves a first apparatus. The target non-terrestrial network device provides a service to the first apparatus after the transition. Prior to the transition, the first device transmits information regarding the predicted timing advance to the second device.

Description

Technical Field

[0001] Various exemplary embodiments of this disclosure generally relate to the telecommunications field, and more specifically to methods, apparatus, devices, and computer-readable storage media for advance timing (TA) reporting. Background Technology

[0002] Non-terrestrial communication can complement terrestrial deployments, where satellite connectivity can provide coverage beyond terrestrial reach. In non-terrestrial network (NTN) systems, fifth-generation (5G) base stations (gNBs) or gNB functionality are deployed on satellites or relayed transparently by gNBs to provide communication coverage over very large areas that would otherwise be inaccessible to cellular networks.

[0003] In NTN, cells originating from different satellites are associated with different Physical Cell Identifiers (PCIs). Therefore, fixed user equipment (UEs) can experience continuous Layer 3 (L3) mobility when the serving satellite moves out of coverage and a new satellite takes over the coverage of a geographic area. A system that maintains the same PCI after satellite transition has been proposed to reduce signaling overhead for UEs and simplify Radio Resource Control (RRC) procedures. Summary of the Invention

[0004] In a first aspect of this disclosure, a first apparatus is provided. The first apparatus includes: at least one processor; and at least one memory storing instructions, which, when executed by the at least one processor, cause the first apparatus to: determine a predicted timing advance associated with the target non-terrestrial network device before switching a connection from a source non-terrestrial network device to a target non-terrestrial network device, the source non-terrestrial network device serving the first apparatus, and after the switching, the target non-terrestrial network device serving the first apparatus; and transmit information about the predicted timing advance to a second device before the switching.

[0005] In a second aspect of this disclosure, a second apparatus is provided. The second apparatus includes: at least one processor; and at least one memory storing instructions, which, when executed by the at least one processor, cause the second apparatus to: receive from a first apparatus, before switching a connection from a source non-terrestrial network device to a target non-terrestrial network device, the source non-terrestrial network device serving the first apparatus, and after the switching, the target non-terrestrial network device serving the first apparatus; and determine, based on the information, a configuration of a transmission time offset for transmissions to the first apparatus.

[0006] In a third aspect of this disclosure, a method is provided. The method includes: determining at a first device a predicted timing advance associated with a target non-terrestrial network device, a source non-terrestrial network device serving the first device, and a target non-terrestrial network device serving the first device after a transition; and transmitting information about the predicted timing advance to a second device prior to the transition.

[0007] In a fourth aspect of this disclosure, a method is provided. The method includes: receiving, at a second device, information from a first device regarding a predicted timing advance associated with the target non-terrestrial network device, the source non-terrestrial network device serving the first device, and the target non-terrestrial network device switching to serve the first device after the transition of a connection from a source non-terrestrial network device to a target non-terrestrial network device; and determining, based on the information, a configuration of a transmission time offset for transmissions to the first device.

[0008] In a fifth aspect of this disclosure, a first apparatus is provided. The first apparatus includes: means for determining a predicted timing advance associated with a target non-terrestrial network device before switching a connection from a source non-terrestrial network device to a target non-terrestrial network device, the source non-terrestrial network device serving the first apparatus, and the target non-terrestrial network device serving the first apparatus after the switching; and means for transmitting information about the predicted timing advance to a second apparatus before the switching.

[0009] In a sixth aspect of this disclosure, a second apparatus is provided. The second apparatus includes components for receiving, from a first apparatus, information about a predicted timing advance associated with the target non-terrestrial network device before switching a connection from a source non-terrestrial network device to a target non-terrestrial network device, the source non-terrestrial network device serving the first apparatus, and the target non-terrestrial network device switching to serve the first apparatus after the switch; and components for determining a configuration of a transmission time offset for transmissions to the first apparatus based on the information.

[0010] In a seventh aspect of this disclosure, a computer-readable medium is provided. The computer-readable medium includes instructions stored thereon for causing an apparatus to perform at least the method according to a third or fourth aspect.

[0011] It should be understood that the summary section is not intended to identify key or essential features of the embodiments of this disclosure, nor is it intended to limit the scope of this disclosure. Other features of the invention will become readily apparent from the following description. Attached Figure Description

[0012] Some exemplary embodiments will now be described with reference to the accompanying drawings, in which: Figure 1A An example communication environment is shown that can implement example embodiments of this disclosure; Figure 1B Another example communication environment is shown that can implement example embodiments of this disclosure; Figure 2 Signaling diagrams for advance timing reporting are shown according to some example embodiments of the present disclosure; Figure 3 Example diagrams illustrating time points for transmission according to some exemplary embodiments of the present disclosure are shown; Figure 4A and Figure 4B Example Media Access Control Element (MAC CE) formats for timed advance reporting are shown according to some example embodiments of this disclosure; Figure 5 Example diagrams illustrating scheduling time relationships according to some exemplary embodiments of the present disclosure are shown; Figure 6 A flowchart is shown illustrating a method implemented at a first device according to some exemplary embodiments of the present disclosure; Figure 7 A flowchart is shown illustrating a method implemented at a second device according to some example embodiments of the present disclosure; Figure 8 A simplified block diagram of a device suitable for implementing example embodiments of the present disclosure is shown; and Figure 9 A block diagram of an example computer-readable medium according to some example embodiments of the present disclosure is shown.

[0013] Throughout the accompanying drawings, the same or similar reference numerals denote the same or similar elements. Detailed Implementation

[0014] The principles of this disclosure will now be described with reference to some exemplary embodiments. It should be understood that these embodiments are described merely for illustration and to help those skilled in the art understand and implement this disclosure, and do not imply any limitation on the scope of this disclosure. The embodiments described herein can be implemented in various ways other than those described below.

[0015] In the following description and claims, unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure pertains.

[0016] References to "an embodiment," "embodiment," "example embodiment," etc., in this disclosure indicate that the described embodiment may include specific features, structures, or characteristics, but not every embodiment necessarily includes such specific features, structures, or characteristics. Furthermore, such phrases do not necessarily refer to the same embodiment. Additionally, when a particular feature, structure, or characteristic is described in connection with an embodiment, it is believed that, to the knowledge of those skilled in the art, other embodiments can be combined to affect such feature, structure, or characteristic, whether explicitly described or not.

[0017] It should be understood that although the terms “first,” “second,” etc., may be used herein to describe various elements, these elements should not be limited by these terms. These terms are used only to distinguish one element from another. For example, a first element may be referred to as a second element, and similarly, a second element may be referred to as a first element, without departing from the scope of the exemplary embodiments. As used herein, the term “and / or” includes any and all combinations of one or more of the listed terms.

[0018] As used herein, “at least one of the following: ” and “at least one of ” and similar wording, wherein a list of two or more elements combined with “and” or “or” means at least one of the elements, or at least any two or more of the elements, or at least all of the elements.

[0019] As used herein, unless explicitly stated otherwise, the execution step “in response to A” does not indicate that the step is executed immediately after “A” occurs, and may include one or more intermediate steps.

[0020] The terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the exemplary embodiments. As used herein, the singular forms “a,” “an,” and “the” are also intended to include the plural forms unless the context clearly indicates otherwise. It will be further understood that the terms “comprising,” “including,” “having,” “having,” “containing,” and / or “comprising”, when used herein, specify the presence of the stated features, elements, and / or components, but do not exclude the presence or addition of one or more other features, elements, components, and / or combinations thereof.

[0021] The term "circuit system" as used in this application may refer to one or more of the following: (a) Hardware circuit implementation only (such as implementation in analog and / or digital circuits only) and (b) A combination of hardware circuitry and software, such as (if applicable): (i) A combination of (multiple) analog and / or digital hardware circuits and software / firmware, and (ii) Any part of a hardware processor (including multiple digital signal processors, software, and multiple memories, which work together to enable a device (such as a mobile phone or server) to perform various functions) and (c) (Multiple) hardware circuits and / or (multiple) processors, such as (multiple) microprocessors or a portion thereof, which require software (e.g. firmware) to operate, but may not exist when the software is not required to operate.

[0022] The definition of "circuit system" applies to all uses of the term in this application, including any claim. As yet another example, as used in this application, the term "circuit system" also covers implementations of hardware circuitry or processors (or processors) or hardware circuitry or processors and their accompanying software and / or firmware. The term "circuit system" also covers, for example (and if applicable to a particular claim element), baseband integrated circuits or processor integrated circuits for mobile devices or similar integrated circuits in servers, cellular network devices, or other computing or networking devices.

[0023] As used herein, the term "communication network" refers to a network that conforms to any suitable communication standard, such as New Radio (NR), Long Term Evolution (LTE), LTE-A Advanced (LTE-A), Wideband Code Division Multiple Access (WCDMA), High-Speed ​​Packet Access (HSPA), Narrowband Internet of Things (NB-IoT), etc. Furthermore, communication between terminal devices and network devices in a communication network can be performed according to any suitable generation of communication protocols, including but not limited to first-generation (1G), second-generation (2G), 2.5G, 2.75G, third-generation (3G), fourth-generation (4G), 4.5G, fifth-generation (5G) communication protocols and / or any other currently known or future-developed protocols. Embodiments of this disclosure can be applied to various communication systems. Given the rapid development of communications, there will naturally be future types of communication technologies and systems that can implement this disclosure. The scope of this disclosure should not be limited to the systems described above.

[0024] As used herein, the term "network device" or "network access device" refers to a node in a communication network through which terminal devices access the network and receive services. Network devices can refer to base stations (BS) or access points (APs), such as Node B (NodeB or NB), evolved Node B (eNodeB or eNB), NR NB (also known as gNB), Remote Radio Unit (RRU), Radio Header (RH), Remote Radio Header (RRH), relay, Integrated Access and Backhaul (IAB) nodes, low-power nodes (such as femtosecond, picosecond, non-terrestrial networks (NTN)) or non-terrestrial network equipment (such as satellite network equipment, Low Earth Orbit (LEO) and Geosynchronous Orbit (GEO) satellites, aircraft network equipment), etc., depending on the terminology and technology applied. In some example embodiments, the Radio Access Network (RAN) split architecture includes centralized units (CUs) and distributed units (DUs) located at the IAB donor node. An IAB node includes a mobile terminal (IAB-MT) portion that behaves similarly to a UE moving toward its parent node, and a DU portion that behaves similarly to a base station moving toward the next-hop IAB node.

[0025] The term "terminal device" refers to any end device that may be capable of wireless communication. As an example and not a limitation, a terminal device may also be referred to as a communication device, user equipment (UE), subscriber station (SS), portable subscriber station, mobile station (MS), or access terminal (AT). Terminal devices may include, but are not limited to, mobile phones, cellular phones, smartphones, Voice over IP (VoIP) phones, wireless local loop phones, tablets, wearable terminal devices, personal digital assistants (PDAs), portable computers, desktop computers, image capture terminal devices (such as digital cameras), gaming terminal devices, music storage and playback devices, in-vehicle wireless terminal devices, wireless endpoints, mobile stations, laptop embedded devices (LEEs), laptop devices (LMEs), USB dongles, smart devices, wireless client devices (CPEs), Internet of Things (IoT) devices, watches or other wearable devices, head-mounted displays (HMDs), vehicles, drones, medical devices and applications (e.g., remote surgery), industrial devices and applications (e.g., robots and / or other wireless devices operating in the context of industrial and / or automated processing chains), consumer electronics devices, devices operating on commercial and / or industrial wireless networks, etc. The terminal device may also correspond to the mobile terminal (MT) portion of an IAB node (e.g., a relay node). In the following description, the terms "terminal device," "communication device," "terminal," "user equipment," and "UE" are used interchangeably.

[0026] As used herein, the terms “resource,” “transmission resource,” “resource block,” “physical resource block” (PRB), “uplink resource,” or “downlink resource” can refer to any resource used to perform communication, such as communication between a terminal device and a network device, including time-domain resources, frequency-domain resources, spatial-domain resources, code-domain resources, or any other resources capable of communication. In the following, unless explicitly stated otherwise, resources in both the frequency and time domains will be used as examples of transmission resources used to describe some exemplary embodiments of this disclosure. Note that the exemplary embodiments of this disclosure are equally applicable to other resources in other domains.

[0027] As briefly mentioned, in NTN systems, 5G base stations (gNBs) or gNB functionality are deployed on satellites or transparently relayed by gNBs to provide communication coverage over very large areas. Among the mechanisms proposed are enhancements to mobility and service continuity for both NTN-NTN and NTN-terrestrial (TN) networks. For example, methods for further enhancements using the New Radio (NR) TN to NR NTN as a baseline could include specifying NTN-NTN handover enhancements for RRC_CONNECTED UEs in quasi-ground fixed cells and ground mobile cells to reduce signaling overhead.

[0028] In NTN, cells originating from different satellites are associated with different PCIs. Therefore, fixed UEs can experience continuous Layer 3 (L3) mobility when the serving satellite moves out of coverage and a new satellite takes over the coverage of a geographic area.

[0029] In some mechanisms, after the target satellite begins providing coverage, the UE can obtain downlink (DL) synchronization by reading the synchronization signal block (SSB) provided by the target satellite. For UL synchronization, the most straightforward approach is to execute a random access channel (RACH) to obtain uplink (UL) synchronization. Clearly, contention-based random access (CBRA) can be an option for obtaining UL synchronization. Contention-free random access (CFRA), which requires dedicated RACH resources for the UE before satellite switching occurs, can also be supported.

[0030] RACH-free handovers are supported in inter-satellite handovers with the same gateway / gNB. The unchanged PCI scenario without handover is similar to the RACH-free inter-satellite handover scenario with the same gateway / gNB. In other words, RACH-free handovers can also be supported for unchanged PCI scenarios. This means that after an inter-satellite handover without RACH, the UE can have a valid TA for the target cell. How to obtain the TA of the target cell may require further discussion.

[0031] After satellite switching and UE resynchronization to the serving cell (via the target satellite), NW will continue to schedule UE transmission for UL using pre-allocated resources or dynamically authorized resources.

[0032] In some mechanisms, immutable PCI has been proposed to reduce signaling overhead for the UE and simplify the Radio Resource Control (RRC) process. In a handover-free immutable PCI scenario, the UE can obtain UL synchronization without RACH.

[0033] In some mechanisms, the CBRA / CFRA procedure can be used by the UE to reacquire UL synchronization with the target satellite in a PCI-invariant scenario without handover. NTN RACH-free handover (HO) can be supported for intra-satellite handovers with the same feeder link, i.e., handovers with the same gateway / gNB. NTN RACH-free HO can also be supported for inter-satellite handovers with different feeder links, i.e., handovers using gateway / gNB, inter-satellite handovers using gateway / gNB, and inter-satellite handovers using the same gateway / gNB.

[0034] Several protocols related to solutions with invariant PCI were discussed. In the case of quasi-Earth fixed cells, for hard satellite transitions with the same Synchronization Signal Block (SSB) frequency and the same gNB (without security key changes), satellite transitions without PCI changes (without requiring L3 mobility) are supported.

[0035] In 3GPP Rel-18, the focus is on transparent architecture, most notably when cells are provided by the same gNB—that is, when identical cells with fixed PCIs are provided by the same gNB. In this case, only the satellite node is changed. However, theoretically, this could also work with different gNBs and potentially even for regeneration scenarios.

[0036] In some mechanisms, how to perform synchronization with the serving cell after satellite handover has been proposed. For example, it has been proposed to support UEs to obtain UL synchronization (to the serving cell after satellite handover) in the absence of a random access channel (RACH) in a non-interventional PCI (no handover) scenario.

[0037] In a PCI-invariant scenario, the satellite will be switched without an L3 mobility procedure (e.g., handover). When a no-RACH procedure is combined with a PCI-invariant solution, the UE can synchronize to the target satellite without RACH. After the switch, the NW continues to schedule the UE dynamically or via pre-allocated resources. In a hard-switching PCI-invariant scenario (i.e., no handover), the UE needs to know when it will attempt to resynchronize.

[0038] However, the UE may experience a TA hopping problem when a satellite transition occurs. When a TA hopping occurs after a satellite transition, if the network (NW) is unaware of the new TA targeting the new satellite, the Physical Uplink Shared Channel (PUSCH) transmission to the target satellite may fail. This is because, to ensure UL transmission, the NW's configured Koffset should satisfy Koffset > TA + UL processing delay – 4, which may not be satisfied when a TA hopping occurs. For example, if the TA increases by 10ms after the transition and the NW does not adjust the Koffset accordingly due to a lack of new TA information, the UE cannot perform UL transmission due to the outdated Koffset.

[0039] Furthermore, if the NW knows the satellite switching time and uses the maximum UE-eNB RTT among all UEs, the scheduling delay will be increased.

[0040] To address at least some of the above-mentioned or other potential problems, a solution regarding timing advance (TA) reporting is proposed. According to an example embodiment, a first device (such as a terminal device) determines the predicted timing advance associated with a target non-terrestrial network device before switching a connection from a source non-terrestrial network device to a target non-terrestrial network device. The source non-terrestrial network device serves the first device. The target non-terrestrial network device provides service to the first device after the switch. Prior to the satellite switch, the first device transmits information about the predicted timing advance to a second device (such as a network device).

[0041] In this way, the second device can obtain the newly predicted TA. Using the newly predicted TA, the second device can continue scheduling in the serving cell after the handover.

[0042] The exemplary embodiments of this disclosure will now be described in detail with reference to the accompanying drawings.

[0043] Figure 1A An example communication environment 100 is shown that can implement exemplary embodiments of the present disclosure. In communication environment 100, a first device 110 and a second device 120 can communicate with each other via a non-terrestrial network (NTN) device 130. In some example embodiments, the NTN device 130 may be a satellite or a high-altitude platform station (HAPS). The second device 120 may communicate with a data network 140.

[0044] In the following description, for illustrative purposes, some exemplary embodiments are described with the first device 110 operating as a terminal device and the second device 120 operating as a network device. However, in some exemplary embodiments, the operations described in connection with the terminal device can be implemented at the network device or other devices, and the operations described in connection with the network device can be implemented at the terminal device or other devices.

[0045] In some example embodiments, if the second device 120 is a network device, it can be a gNB connected to the NTN device 130 (in a transparent architecture) or a gNB located in the NTN device 130 (in a regenerative architecture).

[0046] In some example embodiments, if the first device 110 is a terminal device and the second device 120 is a network device, then the link 134 between the second device 120 and the NTN device 130 can be referred to as a feed link, and the link 132 between the NTN device 130 and the first device 110 can be referred to as a service link.

[0047] In some example embodiments, the first device 110 is located within the service area or coverage of the NTN device 130. For example, the first device 110 may be located in a different beam footprint.

[0048] In some example embodiments, if the first device 110 is a terminal device and the second device 120 is a network device, the link from the second device 120 to the first device 110 is referred to as a downlink (DL), and the link from the first device 110 to the second device 120 is referred to as an uplink (UL). In the DL, the second device 120 is a transmitting (TX) device (or transmitter), and the first device 110 is a receiving (RX) device (or receiver). In the UL, the first device 110 is a TX device (or transmitter), and the second device 120 is an RX device (or receiver).

[0049] It should be understood that Figure 1A The number of devices and their connections shown are for illustrative purposes only and do not imply any limitation. Communication environment 100 may include any suitable number of devices configured to implement the exemplary embodiments of this disclosure.

[0050] Communication in communication environment 100 can be implemented according to any suitable communication protocol, including but not limited to cellular communication protocols such as first-generation (1G), second-generation (2G), third-generation (3G), fourth-generation (4G), fifth-generation (5G), and sixth-generation (6G), wireless local area network communication protocols such as IEEE 802.11, and / or any other currently known or future-developed protocols. Furthermore, communication can utilize any suitable wireless communication technology, including but not limited to: Code Division Multiple Access (CDMA), Frequency Division Multiple Access (FDMA), Time Division Multiple Access (TDMA), Frequency Division Duplex (FDD), Time Division Duplex (TDD), Multiple-Input Multiple-Output (MIMO), Orthogonal Frequency Division Multiple Access (OFDM), Discrete Fourier Transform Extended OFDM (DFT-s-OFDM), and / or any other currently known or future-developed technologies.

[0051] In some example embodiments, NTN device switching, such as satellite switching, may occur in certain situations. Figure 1B Another example communication environment 150 is shown that can implement exemplary embodiments of the present disclosure. In communication environment 150, NTN device switching can occur.

[0052] In the following description, it may be assumed that the first device 110 is stationary or mobile, and that it is currently served by NTN device 130. For example, NTN device 130 may be a serving satellite or a source satellite. As used herein, serving NTN device 130 may also be referred to as source NTN device 130.

[0053] When the source NTN device 130 moves away from the first device 110, for example, in the direction of movement 155, and another NTN device 160 moves closer to the first device, an NTN device switching will occur at a point in time. As used herein, the NTN device 160 may be referred to as the “target NTN device 160”, which serves the first device 110 after the NTN device switching. As used herein, the term “NTN device switching” may also be referred to as “switching”.

[0054] The network (e.g., second device 120) can instruct first device 110 when a transition will occur. Second device 120 instructs first device 110 when and how to perform DL and UL resynchronization to the new cell after the transition. First device 110 can adjust its timing and Doppler offset parameters for operation toward the new cell. Second device 120 can alternatively accept interruptions used by first device 110 to detect and adapt to new timing gaps. Since the PCI, second device 120, security key, and SSB frequency remain the same, the transition can be largely transparent to first device 110. Satellite transitions can also be largely transparent to first device 110 because the PCI, gNB, security key, and SSB frequency remain the same. Once the target NTN device 160 takes over, first device 110 can perform DL / UL synchronization operations to adjust the time and frequency.

[0055] In some example embodiments, for a quasi-Earth fixed cell (EFC) scenario, geographic region 170 is associated with a Physical Cell ID (PCI) and a second device 120. For a constant PCI scenario, the second device 120 can serve the same coverage (e.g., geographic region 170) by connecting to different NTN devices (e.g., source NTN device 130 and target NTN device 160), and the PCI can remain unchanged after satellite conversion. In this case, the NTN cell is deployed as an EFC because the cell's coverage area does not change.

[0056] When an NTN device transition occurs, the serving NTN device changes from the source NTN device 130 to the target NTN device 160. The service link 132 between the first device 110 and the source NTN device 130 can be changed to a different service link 162 between the first device 110 and the target NTN device 160. Similarly, the feed link 134 between the second device 110 and the source NTN device 130 can be changed to a different feed link 164 between the second device 120 and the target NTN device 160.

[0057] like Figure 1B As shown, if the first device is served by the source NTN device 130, the TA of the first device 110 can be equal to the round-trip time (RTT) between the first device 110 and the second device 120, which includes the propagation delay SL_1 corresponding to the serving link 132 and the propagation delay FL_1 corresponding to the feed link 134 (i.e., SL_1 + FL_1). After the first device 110 switches to the target NTN device 160, the new TA of the first device 110 can be equal to the round-trip time (RTT) between the first device 110 and the second device 120, which includes the propagation delay SL_2 corresponding to the serving link 162 and the propagation delay FL_2 corresponding to the feed link 164 (i.e., SL_2 + FL_2).

[0058] If the first device 110 is located near the edge of the coverage area of ​​the source NTN device 130, a TA hopping problem will occur after the transition because (SL_2+FL_2) is greater than (SL_1+FL_1). The value of the TA hopping (also known as the TA hopping value) can depend on the cell coverage radius, the serving satellite elevation angle, and the location of the first device 110. For example, the TA hopping value can be at least greater than the differential delay between UEs serving the satellite. As an example, the TA hopping value can be 10 ms in geosynchronous equatorial orbit (GEO). It should be understood that the TA hopping value can be any suitable time value.

[0059] In some example embodiments, the second device 120 may need to know the new TA of the target NTN device 160 to obtain the TA transition value. According to some example embodiments of this disclosure, before switching the connection from the source NTN device 130 serving the first device 110 to the target NTN device 160, the first device 110 determines the predicted TA associated with the target NTN device 160. The target NTN device 160 is used to provide service to the first device 110 after the switch. The first device 110 transmits information about the predicted timing advance to the second device 120 before the switch.

[0060] In this way, the second device 120 can be notified of the newly predicted TA. Using the newly predicted TA, the second device 120 can continue scheduling in the serving cell after the handover.

[0061] Figure 2 Signaling diagram 200 for TA reporting is shown according to some example embodiments of the present disclosure. Signaling diagram 200 relates to... Figure 1A and Figure 1B The first device 110 and the second device 120 are described. For illustrative purposes, reference will be made to... Figure 1A and Figure 1B Description of signaling diagram 200.

[0062] Despite Figure 2 A single first device 110 and a single second device 120 are shown, but it should be understood that multiple devices may exist that perform similar operations to those described below with respect to the first device 110 or the second device 120.

[0063] exist Figure 2 In some examples, the second device 120 may be connected to at least one of the following: the source NTN device 130 before conversion and the target NTN device 160. Alternatively, in some example embodiments, the second device 120 may be located in at least one of the following: the source NTN device 130 before conversion and the target NTN device 160. The source NTN device 130 and / or the target NTN device 160 may be a satellite or a high-altitude platform station.

[0064] It should be noted that the exemplary embodiments of this disclosure can be applied to any suitable scenario, such as a no-RACH satellite handover scenario in a constant PCI scenario, or a no-RACH transition scenario in an NTN scenario if a no-RACH satellite transition exists. For illustrative purposes only, the exemplary embodiments of this disclosure are described with reference to a no-RACH satellite transition scenario.

[0065] In operation, before converting a connection from a source NTN device (such as source NTN device 130) to a target NTN device, the first device 110 determines (230) a predicted TA associated with the target NTN device (such as target NTN device 160). The source NTN device serves the first device 110. The target NTN device is used to serve the first device 110 after conversion.

[0066] Before the transition, the first device 110 transmits (250) information about the timing advance of the prediction to the second device 120. The second device 120 receives (255) this information. For example, before the satellite transition occurs, the first device 110 reports the predicted TA for the serving cell with the target satellite to the second device 120.

[0067] In some example embodiments, the first device 110 may transmit at least one of the following to the second device 120 at a first time point prior to the transition time window: the information, or a request for transmission of the information. For example, if resources are available for transmission at the first time point, the first device 110 may transmit (250) the information at the first time point. If no resources are available for information transmission at the first time point, the first device 110 may transmit a request for transmission at the first time point. That is, the first device 110 may trigger a predicted TA report for the target NTN device 160 before the transition. For example, the request for information transmission may be a scheduling request or a random access request.

[0068] In some example embodiments, the time window can be predefined or configured. As an example, the second device 120 can transmit (240) the time window configuration to the first device 110. The first device 110 can receive (245) the time window configuration. The second device 120 can assume that the TA information transmission can be completed within the time window.

[0069] In some example embodiments, the second device 120 may determine the time window based on at least one of the following: the RTT between the first device 110 and the second device 120, the number of retransmissions, or the scheduling request (SR) period. It should be understood that these example parameters used to determine the time window are for illustrative purposes only and do not imply any limitation. The second device 120 may determine the time window based on any other suitable parameters.

[0070] Figure 3 Example diagram 300 illustrates the timing of information transmission according to some exemplary embodiments of this disclosure. As shown, time window 310 is configured by second device 120. Time window 310 precedes transition time point 330. Information regarding the predicted TA or requests for information transmission can be sent at a first time point 340 before the start time point 335 of time window 310. It should be understood that in some exemplary embodiments, the first time point 340 may be at the start time point 335 of time window 310. In this way, first device 110 can trigger a predicted TA report for target NTN device 160 before the (satellite transition time - time window) point. Figure 3 The document shows additional time points that will be used for the transmission of additional information.

[0071] Return to reference Figure 2In some example embodiments, the predicted TA information may be transmitted (250) based on one or more conditions. For example, the first device 110 may determine (235) whether the difference between the predicted TA associated with the target NTN device 160 and the reference TA associated with the source NTN device 130 is greater than or equal to a threshold. If the first device 110 determines (235) that the difference is greater than or equal to the threshold, the first device 110 may transmit (250) the information to the second device 120.

[0072] In this manner, the first device 110 only reports the predicted TA for the serving cell with the target NTN device 160 when the change between the reported TA for the serving cell with the source NTN device 130 and the predicted TA for the serving cell with the target NTN device 160 is greater than or equal to a threshold. Signaling overhead can thus be reduced.

[0073] It should be understood that conditions other than the threshold can be used to predict the transmission of TA information. The scope of this disclosure is not limited in this respect.

[0074] As described, the first device 110 determines (230) the predicted TA. In some example embodiments, the second device 120 may transmit (220) the ephemeris information and TA parameter set of the target NTN device 160 to the first device 110. The first device 110 may receive (225) the ephemeris information and TA parameter set of the target NTN device 160. As an example, the TA parameter set may be common TA parameters. The first device 110 may determine (230) the predicted TA based on the ephemeris information and the TA parameter set.

[0075] In this manner, the second device 120 provides the first device 110 with ephemeris information of the target NTN device 160, such as the target satellite's ephemeris information and common TA parameters, before the satellite switching occurs. Therefore, it enables the first device 110 to predict the TA for the serving cell using the target satellite.

[0076] In some example embodiments, the second device 120 may transmit (220) ephemeris information and a set of TA parameters to the first device 110 at a second time point prior to a first time point for a predicted TA request or report. The offset of the second time point relative to the first time point may be predefined or configured. In another example, the offset of the second time point relative to the time window used for the predicted TA transmission may be predefined or configured. For example, the second device 120 may transmit (210) a configuration of the offset to the first device 110. The first device 110 may receive (215) the configuration of the offset. This offset may be relative to the first time point or a time window associated with the first time point.

[0077] like Figure 3 As shown, offset 320 is configured by the second device 120. Offset 320 precedes time point 335 of time window 310. Ephemeris information and TA parameter sets can be transmitted at a second time point 350 prior to time point 345 with offset 320 relative to time window 310 (210). It should be understood that in some example embodiments, the second time point 350 may be at time point 345.

[0078] In this manner, the second device 120 can configure an offset to the first device 110, wherein the second device 120 can provide information and TA parameters of the target NTN device 160 at a time point of (satellite transition time - time window - offset). As an example, the ephemeris information and TA parameter set can be provided to the first device 110 via a System Information Block (SIB) or any other suitable signaling. For example, in connected mode, the t-Service in SIB 19 can be interpreted by the first device 110 to indicate a satellite change or a feed link change. The first device 110 can begin receiving or decoding the ephemeris information and TA parameter set from a second time point.

[0079] In some example embodiments, the second device 120 can determine the offset value by taking into account the time required for TA estimation in the first device 110 based on ephemeris and public TA and the configured system information (SI) modification period.

[0080] In some example embodiments, the predicted TA for the serving cell with the target NTN device 160 can be reported in different formats. In one example, information about the predicted TA may include the predicted TA associated with the target NTN device 160, such as the predicted TA value. The first device 110 may report the predicted TA via an RRC message such as UE assistance information, wherein the absolute value of the predicted TA may be included. The first device 110 may alternatively report the predicted TA via a new Media Access Control Element (MAC CE), such as a new UL MAC CE. For example, multiple most significant bits (MSBs) or multiple least significant bits (LSBs) in at least one octet (OCT) in the MAC CE may be used for the predicted TA value.

[0081] Figure 4AAn example MAC CE format 410 for TA reporting is shown. The MAC CE for the predicted TA report can be identified by a MAC subheader with a Logical Channel Identifier (LCID). For example, six LSB bits of the first OCT 412 and eight bits of the second OCT 414 immediately following the first OCT 412 in the MAC CE can be used for the predicted TA value. Two MSB bits in the first OCT 412 can be reserved. The reserved bits can be set to 0. It should be understood that this example MAC CE format 410 is for illustrative purposes only and does not imply any limitation. Any appropriate MAC CE can be applied. The scope of this disclosure is not limited in this respect.

[0082] Alternatively or additionally, in some example embodiments, information about the predicted TA may include a reference TA associated with the source NTN device 130 and the difference between the predicted TA and the reference TA. As used herein, the difference between the predicted TA and the reference TA may also be referred to as a “TA difference”, a “TA transition”, or a “TA transition value.” For example, the difference between the predicted TA and the reference TA may be carried in at least one reserved bit in the MAC CE. This at least one reserved bit may indicate the ratio of the difference to a predetermined TA difference.

[0083] Multiple bits in the MAC CE can be used to reference the TA. For example, in a frequency range 1 (FR1) scenario, the TA field uses a subcarrier spacing of 15 kHz to indicate the minimum integer number of time slots greater than or equal to the TA value. The length of this field can be 14 bits. That is, 14 bits can be used to reference the TA. It should be understood that in other scenarios, more or fewer bits can be used to reference the TA.

[0084] Figure 4B An example MAC CE format 430 for predicting the TA and a reference TA is shown. As shown, the two MSB bits in the first OCT 432 of the MAC CE indicate the difference between the predicted TA and the reference TA. The six LSB bits in the OCT 432 of the MAC CE and the eight bits in the second OCT 434 immediately following the first OCT 432 indicate the reference TA value. It should be understood that this example MAC CE format 430 is for illustrative purposes only and does not imply any limitation. Any suitable MAC CE may be applied. The scope of this disclosure is not limited in this respect.

[0085] In some example embodiments, the second device 120 may indicate a predetermined TA difference, such as the maximum TA transition, to the first device 110 via RRC or SIB. Alternatively, the predetermined TA difference or the maximum TA transition may be predefined, such as 20 ms or any suitable value.

[0086] The first device 110 can indicate the TA transition via an index in the free bits of the MAC CE to indicate the percentage of the maximum TA transition. Figure 4B In the example, two reserved bits can indicate the TA transition value. The indices in the two reserved bits can be 00 / 01 / 10 / 11. For example, "00" indicates that the TA transition value is less than one-quarter of the maximum TA transition, "01" indicates that the TA transition value is in the range of one-quarter to one-half of the maximum TA transition, "10" indicates that the TA transition value is in the range of one-half to three-quarters of the maximum TA transition, and "11" indicates that the TA transition value is in the range of three-quarters to the entire maximum TA transition. Alternatively, the index "00" can be used to indicate no TA transition, while the indices "01" / "10" / "11" can be used to indicate other TA transition ranges. It should be understood that these example indices and TA transition ranges are for illustrative purposes only and do not imply any limitations.

[0087] The predicted TA for a serving cell with target NTN device 160 can be equal to the sum of the TA value reported by the serving cell with source NTN device 130 and the TA hopping. For example... Figure 4B As shown, the TA value for the source NTN device 130 can be indicated by the conventional 14 bits in the UL MAC CE, while the TA transition can be indicated by two idle bits in the same MAC CE.

[0088] In this way, both the TA for the serving cell with the source NTN device 130 and the TA for the serving cell with the target NTN device 160 are reported to the second device 120 via a single UL MAC CE. Signaling can therefore be more efficient. The signaling design is efficient by reusing the R bits in the conventional UL MAC CE for TA reporting of the serving cell with the source satellite.

[0089] Back Figure 2 In some example embodiments, the second device 120 determines (260) a transmission time offset configuration for the transmission of the first device 110 based on information about the predicted TA. The second device 120 may transmit (265) the transmission time offset configuration to the first device 110. The first device 110 may receive (270) the configuration. As used herein, the transmission time offset may also be referred to as a "first device 110-specific Koffset" or a "UE-specific Koffset".

[0090] In some example embodiments, the second device 120 may indicate the transmission time offset used for scheduling after the transition via a DL MAC CE as defined in the conventional. Alternatively or additionally, in some example embodiments, the second device 120 may indicate the transmission time offset used for scheduling after the transition via a Physical Downlink Control Channel (PDCCH) or RRC. This is advantageous for adjusting the UE-specific Koffset after the transition in conjunction with UL authorization.

[0091] In one example, based on the reported TA of the target NTN device 160, during a transition such as satellite switching, the second device 120 can schedule the first device 110 based on the new TA. Alternatively or additionally, the second device 120 can schedule the first device 110 based on a new TA after an interruption length following the transition (e.g., satellite switching + interruption length). The interruption length can be predefined or configured. In one example, the interruption length can be the time used for the first device 110 to resynchronize to the target NTN device 160.

[0092] The first device 110 can convert (275) the connection from the source target NTN device 130 to the target NTN device 160. After conversion (275), the first device 110 can perform (280) transmission based on the configuration of the received (270) transmission time offset.

[0093] In some example embodiments, the PUSCH transmission may be delayed by Koffset compared to this transmission. Koffset may be the result of a cell-specific Koffset (indicated by the SIB) minus a first device 110-specific Koffset (indicated by the MAC CE), such as a UE-specific Koffset. The first device 110-specific Koffset, such as a UE-specific Koffset, may be a transmission time offset configured by the second device 120.

[0094] A cell-specific Koffset can be considered a coarse value applied to all first devices in the cell, which can be greater than the maximum TA among all first devices. A UE-specific Koffset is the variable (delta) applied to it. Using the TA reported from first device 110, the auxiliary network may configure an appropriate UE-specific Koffset for first device 110, which can reduce UL latency and improve scheduling efficiency. For example, the final Koffset may be larger but closer to the RTT between first device 110 and second device 120, instead of using the maximum UE-eNB RTT among all UEs. In other words, if no TA report is available, the NW cannot configure a UE-specific Koffset, and therefore the UE must apply the final Koffset as a cell-specific Koffset.

[0095] Therefore, by configuring the transmission time offset (i.e., Koffset specific to the first device 110), UL latency can be reduced and scheduling efficiency can be improved.

[0096] In order to ensure that the first device 110 has sufficient time for TA adjustment and UL processing delay, the timing of the scheduled transmission of the first device 110 needs to be greater than the actual transmission time of the first device 110 application.

[0097] Figure 5 Example Figure 500 is shown illustrating scheduling time relationships according to some example embodiments of the present disclosure. Figure 5 In the description, it is assumed that the first device 110 is implemented as a terminal device and the second device 120 is implemented as a network device. As shown in the figure, the timing of the scheduled UL transmission of the first device 110 (i.e., n+4+Koffset) needs to be greater than the actual transmission time applied by the first device 110 (i.e., n+TA+UL processing delay). In other words, (Koffset+4) needs to be greater than (TA+UL processing delay). The value of Koffset can be configured by the second device 120 based on predefined or configured conditions. An example condition could be Koffset>TA + UL processing delay - 4. Under this condition, it can be ensured that the timing of the scheduled transmission of the first device 110 is greater than the actual transmission time applied by the first device 110.

[0098] Using the predicted transmission time offset (TA) information, the second device 120 can configure a transmission time offset (such as a UE-specific Koffset) based on the predicted TA and the condition that Koffset > TA + UL processing delay - 4. It should be understood that such example conditions are for illustrative purposes only and do not imply any limitations. Any suitable conditions or calculations can be applied to determine the transmission time offset based on the predicted TA. The scope of this disclosure is not limited in this respect.

[0099] This solution enables the UE to report the predicted TA for the serving cell with the target satellite in satellite handover scenarios without RACH. This is mandatory to avoid authorized UL transmission failures, as Koffset can be configured / adapted based on the UE-specific RTT. By using the predicted TA report for satellite handover in satellite handover scenarios without RACH in the invariant PCI scenario, UL transmission failures scheduled after handover can be avoided.

[0100] Figure 6 A flowchart of an example method 600 implemented at a first device according to some example embodiments of the present disclosure is shown. For the purposes of discussion, method 600 will be discussed from... Figure 1A and Figure 1BThe angle of the first device 110 in the middle is described.

[0101] In block 610, the first device 110 determines a predicted timing advance associated with the target non-terrestrial network device before switching the connection from a source non-terrestrial network device to a target non-terrestrial network device. The source non-terrestrial network device serves the first device, and the target non-terrestrial network device serves the first device after the switch.

[0102] At frame 620, the first device 110 transmits information about the timing advance of the prediction to the second device before the conversion.

[0103] In some example embodiments, method 600 further includes: transferring the connection from the source non-terrestrial network device to the target non-terrestrial network device without a random access procedure.

[0104] In some example embodiments, method 600 further includes transmitting at least one of the following to the second device at a first time point prior to the conversion time window: information, a request for the transmission of information.

[0105] In some example embodiments, method 600 further includes receiving a configuration of a time window from a second device.

[0106] In some example embodiments, method 600 further includes: determining that the difference between a predicted timing advance associated with a target non-terrestrial network device and a reference timing advance associated with a source non-terrestrial network device is greater than or equal to a threshold; and based on the determination, transmitting information to a second device.

[0107] In some example embodiments, the information includes at least one of the following: the predicted timing advance associated with the target non-terrestrial network device, the reference timing advance associated with the source non-terrestrial network device, and the difference between the predicted timing advance and the reference timing advance.

[0108] In some example embodiments, the predicted timing advance is carried in the Media Access Control (MAC) control element, or the difference between the predicted timing advance and the reference timing advance is carried in at least one reserved bit in the MACC control element, and the at least one reserved bit indicates the ratio of the difference to the predetermined timing advance.

[0109] In some example embodiments, method 600 further includes: receiving ephemeris information and a timing advance parameter set of the target non-terrestrial network device from the second device; and determining the predicted timing advance based on the ephemeris information and the timing advance parameter set.

[0110] In some example embodiments, method 600 further includes: receiving ephemeris information and a set of timing advance parameters from a second device at a second time point prior to the first time point, wherein at least one of the information and a transmission request for the information is transmitted to the second device at the first time point.

[0111] In some example embodiments, method 600 further includes: receiving a configuration of the offset of a second time point relative to a first time point from a second device.

[0112] Figure 7 A flowchart of an example method 700 implemented at a second device according to some example embodiments of the present disclosure is shown. For the purposes of discussion, method 700 will be discussed from... Figure 1A and Figure 1B The perspective of the second device 120 in the diagram is described.

[0113] At box 710, the second device 120 receives from the first device information regarding the timing advance of a prediction associated with the target non-terrestrial network device before switching the connection from the source non-terrestrial network device to the target non-terrestrial network device. The source non-terrestrial network device serves the first device, and the target non-terrestrial network device serves the first device after the switch.

[0114] At box 720, the second device 120 determines the configuration of the transmission time offset for the transmission of the first device based on this information.

[0115] In some example embodiments, method 700 further includes receiving at least one of the following from the first device at a first time point prior to the conversion time window: information, a request for transmission of information.

[0116] In some example embodiments, method 700 further includes: determining a time window based on at least one of the following: round-trip time between the first device and the second device, number of retransmissions, scheduling request period; and configuration of the time window for transmission to the first device.

[0117] In some example embodiments, the information includes at least one of the following: a predicted timing advance associated with the target non-terrestrial network device, a reference timing advance associated with the source non-terrestrial network device, and the difference between the predicted timing advance and the reference timing advance.

[0118] In some example embodiments, the predicted timing advance is carried in the media access control element, or the difference between the predicted timing advance and the reference timing advance is carried in at least one reserved bit in the media access control element, and the at least one reserved bit indicates the ratio of the difference to the predetermined timing advance.

[0119] In some example embodiments, method 700 further includes transmitting ephemeris information and a set of timing advance parameters of the target non-terrestrial network device to the first device.

[0120] In some example embodiments, method 700 further includes: transmitting ephemeris information and a set of timing advance parameters to a first device at a second time point prior to the first time point, wherein at least one of receiving information from the first device and a request for the transmission of information is received at the first time point.

[0121] In some example embodiments, method 700 further includes: transmitting to the first device a configuration of the offset of the second time point relative to the first time point.

[0122] In some example embodiments, method 700 further includes: transmitting a configuration of the transmission time offset to the first device.

[0123] In some example embodiments, the second device is connected to at least one of the following: the source non-terrestrial network device before conversion, the target non-terrestrial network device, or the second device is located in at least one of the following: the source non-terrestrial network device before conversion, the target non-terrestrial network device.

[0124] In some example embodiments, the non-terrestrial network equipment includes at least one of the following: satellite, high-altitude platform station.

[0125] In some example embodiments, a first device capable of performing any of method 600 (e.g., Figure 1A and Figure 1B The first device 110 may include a component for performing the corresponding operation of method 600. This component may be implemented in any suitable form. For example, the component may be implemented in a circuit or software module. The first device may be implemented as or included in... Figure 1A and Figure 1B In the first device 110.

[0126] In some example embodiments, the first device includes: components for determining a predicted timing advance associated with a target non-terrestrial network device before switching the connection from a source non-terrestrial network device to a target non-terrestrial network device, the source non-terrestrial network device serving the first device, and the target non-terrestrial network device serving the first device after the switching; and components for transmitting information about the predicted timing advance to a second device before the switching.

[0127] In some example embodiments, the first device further includes a component for transferring a connection from a source non-terrestrial network device to a target non-terrestrial network device without a random access procedure.

[0128] In some example embodiments, the first device further includes a component for transmitting at least one of the following to the second device at a first point in time prior to the transition time window: information, a request for the transmission of information.

[0129] In some example embodiments, the first device further includes a component for receiving a configuration of a time window from the second device.

[0130] In some example embodiments, the first device further includes: a component for determining that the difference between a predicted timing advance associated with a target non-terrestrial network device and a reference timing advance associated with a source non-terrestrial network device is greater than or equal to a threshold; and a component for transmitting information to a second device based on the determination.

[0131] In some example embodiments, the information includes at least one of the following: a predicted timing advance associated with the target non-terrestrial network device, a reference timing advance associated with the source non-terrestrial network device, and the difference between the predicted timing advance and the reference timing advance.

[0132] In some example embodiments, the predicted timing advance is carried in the Media Access Control (MAC) control element, or the difference between the predicted timing advance and the reference timing advance is carried in at least one reserved bit in the MACC control element, and the at least one reserved bit indicates the ratio of the difference to the predetermined timing advance.

[0133] In some example embodiments, the first device further includes: a component for receiving ephemeris information and a timing advance parameter set of the target non-terrestrial network device from the second device; and a component for determining the predicted timing advance based on the ephemeris information and the timing advance parameter set.

[0134] In some example embodiments, the first device further includes: a component for receiving ephemeris information and a set of timing advance parameters from the second device at a second time point prior to the first time point, wherein at least one of transmitting information to the second device and a request for transmitting information is made at the first time point.

[0135] In some example embodiments, the first device further includes a component for receiving a configuration of the offset of a second time point relative to a first time point from the second device.

[0136] In some example embodiments, the first device further includes components for performing other operations in some example embodiments of method 600 or the first device 110. In some example embodiments, the device includes: at least one processor; and at least one memory storing instructions that, when executed by the at least one processor, cause execution of the first device.

[0137] In some example embodiments, a second means capable of performing any of the methods 700 (e.g., Figure 1A and Figure 1B The second device 120 may include a component for performing the corresponding operation of method 700. This component may be implemented in any suitable form. For example, the component may be implemented in a circuit or software module. The second device may be implemented as or included in... Figure 1A and Figure 1B The second device 120 in the middle.

[0138] In some example embodiments, the second means includes means for receiving information from the first means regarding a predicted timing advance associated with the target non-terrestrial network device before switching the connection from a source non-terrestrial network device to a target non-terrestrial network device, the source non-terrestrial network device serving the first device, and the target non-terrestrial network device serving the first device after the switch; and components for determining a configuration of a transmission time offset for the transmission to the first device based on the information.

[0139] In some example embodiments, the second device further includes a component for receiving at least one of the following from the first device at a first time point prior to the conversion time window: information, a request for transmission of information.

[0140] In some example embodiments, the second device further includes: components for determining a time window based on at least one of the following: round-trip time between the first device and the second device, number of retransmissions, and scheduling request period; and components for transmitting the configuration of the time window to the first device.

[0141] In some example embodiments, the information includes at least one of the following: a predicted timing advance associated with the target non-terrestrial network device, a reference timing advance associated with the source non-terrestrial network device, and the difference between the predicted timing advance and the reference timing advance.

[0142] In some example embodiments, the predicted timing advance is carried in the Media Access Control (MAC) control element, or the difference between the predicted timing advance and the reference timing advance is carried in at least one reserved bit in the MACC control element, and the at least one reserved bit indicates the ratio of the difference to the predetermined timing advance.

[0143] In some exemplary embodiments, the second device further includes a component for transmitting ephemeris information and a set of timing advance parameters of the target non-terrestrial network device to the first device.

[0144] In some example embodiments, the second device further includes: a component for transmitting ephemeris information and a set of timing advance parameters to the first device at a second time point prior to the first time point, wherein at least one of receiving information from the first device and a request for transmitting information is received at the first time point.

[0145] In some example embodiments, the second device further includes a component for transmitting a configuration of the offset of the second time point relative to the first time point to the first equipment.

[0146] In some example embodiments, the second device further includes a component for transmitting a configuration of the transmission time offset to the first device.

[0147] In some example embodiments, the second device is connected to at least one of the following: the source non-terrestrial network device before conversion, the target non-terrestrial network device, or the second device is located in at least one of the following: the source non-terrestrial network device before conversion, the target non-terrestrial network device.

[0148] In some example embodiments, the non-terrestrial network equipment includes at least one of the following: satellite, high-altitude platform station.

[0149] In some example embodiments, the second device further includes components for performing other operations in some example embodiments of method 700 or the second device 120. In some example embodiments, the device includes: at least one processor; and at least one memory storing instructions that, when executed by the at least one processor, cause execution of the first device.

[0150] Figure 8 This is a simplified block diagram of a device 800 suitable for implementing an example embodiment of the present disclosure. Device 800 can be provided for implementing a communication device, such as... Figure 1A and Figure 1B The first device 110 or the second device 120 shown. As shown, device 800 includes one or more processors 810, one or more memories 820 coupled to processor 810, and one or more communication modules 840 coupled to processor 810.

[0151] Communication module 840 is used for bidirectional communication. Communication module 840 has one or more communication interfaces to support communication with one or more other modules or devices. The communication interface can represent any interface necessary for communication with other network elements. In some example embodiments, communication module 840 may include at least one antenna.

[0152] Processor 810 can be any type suitable for a local technology network and can include one or more of the following: general-purpose computer, special-purpose computer, microprocessor, digital signal processor (DSP), and processor based on a multi-core processor architecture, as non-limiting examples. Device 800 can have multiple processors, such as application-specific integrated circuit chips, which are time-dependent on the clock of a synchronous main processor.

[0153] Memory 820 may include one or more non-volatile memories and one or more volatile memories. Examples of non-volatile memories include, but are not limited to, read-only memory (ROM) 824, electrically programmable read-only memory (EPROM), flash memory, hard disk, compact disc (CD), digital video disc (DVD), optical disc, laser disc, and other magnetic and / or optical storage. Examples of volatile memories include, but are not limited to, random access memory (RAM) 822 and other volatile memories that do not persist during power-off periods.

[0154] Computer program 830 includes computer-executable instructions that are executed by an associated processor 810. The instructions of program 830 may include instructions for performing operations / actions of some example embodiments of this disclosure. Program 830 may be stored in memory, such as ROM 824. Processor 810 can perform any suitable actions and processes by loading program 830 into RAM 822.

[0155] Example embodiments of this disclosure can be implemented by means of 830, such that device 800 can perform as described in the reference. Figures 2 to 7 Any process discussed in this disclosure. Exemplary embodiments of this disclosure may also be implemented using hardware or a combination of software and hardware.

[0156] In some example embodiments, program 830 may be tangibly contained in a computer-readable medium, which may be included in device 800 (such as in memory 820) or other storage devices accessible to device 800. Device 800 may load program 830 from the computer-readable medium into RAM 822 for execution. In some example embodiments, the computer-readable medium may include any type of non-transient storage medium, such as ROM, EPROM, flash memory, hard disk, CD, DVD, etc. As used herein, the term "non-transient" refers to a limitation on the medium itself (i.e., tangible, not tactile), rather than a limitation on the persistence of data storage (e.g., RAM versus ROM).

[0157] Figure 9 An example of a computer-readable medium 900, which may be in the form of a CD, DVD, or other optical storage disc, is shown. A program 830 is stored on the computer-readable medium 900.

[0158] Generally, the various embodiments of this disclosure can be implemented in hardware or dedicated circuitry, software, logic, or any combination thereof. Some aspects may be implemented in hardware, while others may be implemented in firmware or software executable by a controller, microprocessor, or other computing device. Although various aspects of the embodiments of this disclosure are shown and described as block diagrams, flowcharts, or using some other graphical representation, it should be understood that, as non-limiting examples, the blocks, apparatuses, systems, techniques, or methods described herein may be implemented in hardware, software, firmware, dedicated circuitry or logic, general-purpose hardware or controllers or other computing devices, or some combination thereof.

[0159] Some exemplary embodiments of this disclosure also provide at least one computer program product tangibly stored on a computer-readable medium, such as a non-transitory computer-readable medium. The computer program product includes computer-executable instructions, such as those included in a program module that executes in a device on a target physical or virtual processor, to perform any of the methods described above. Typically, a program module includes routines, programs, libraries, objects, classes, components, data structures, etc., that perform a particular task or implement a particular abstract data type. In various embodiments, the functionality of a program module can be combined or split among program modules as needed. The machine-executable instructions for a program module can execute within a local or distributed device. In a distributed device, the program module can reside on both local and remote storage media.

[0160] The program code used to perform the methods of this disclosure may be written in any combination of one or more programming languages. The program code may be provided to a processor or controller of a general-purpose computer, special-purpose computer, or other programmable data processing apparatus, such that, when executed by the processor or controller, the program code enables the functions / operations specified in the flowcharts and / or block diagrams to be implemented. The program code may be executed entirely on a machine, partially on a machine, as a stand-alone software package, partially on a machine and partially on a remote machine, or entirely on a remote machine or server.

[0161] In the context of this disclosure, computer program code or related data may be carried by any suitable carrier to enable a device, apparatus, or processor to perform the various processes and operations described above. Examples of carriers include signals, computer-readable media, etc.

[0162] Computer-readable media can be computer-readable signal media or computer-readable storage media. Computer-readable media can include, but is not limited to, electronic, magnetic, optical, electromagnetic, infrared, or semiconductor systems, apparatuses, or devices, or any suitable combination thereof. More specific examples of computer-readable storage media will include electrical connections having one or more wires, portable computer floppy disks, hard disks, random access memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM or flash memory), optical fibers, portable optical disc read-only memory (CD-ROM), optical storage devices, magnetic storage devices, or any suitable combination thereof.

[0163] Furthermore, although the operations are described in a specific order, this should not be construed as requiring that such operations be performed in the specific order shown or sequentially, or that all the operations shown be performed to achieve the desired result. In some cases, multitasking and parallel processing may be advantageous. Similarly, although several specific implementation details are included in the discussion above, these should not be construed as limiting the scope of this disclosure, but rather as descriptions of features that may be specific to particular embodiments. Unless explicitly stated otherwise, certain features described in the context of a single embodiment may also be implemented in combination in a single embodiment. Conversely, unless explicitly stated otherwise, various features described in the context of a single embodiment may also be implemented individually or in any suitable sub-combination in multiple embodiments.

[0164] Although this disclosure has been described in language specific to structural features and / or methodological actions, it should be understood that the disclosure as defined in the appended claims is not necessarily limited to the specific features or actions described above. Rather, the specific features and actions described above are disclosed as exemplary forms for implementing the claims.

Claims

1. A first apparatus comprising: at least one processor; and at least one memory storing instructions that, when executed by the at least one processor, cause the first apparatus to: determine, prior to a transition of a connection from a source non-terrestrial network device to a target non-terrestrial network device, a predicted timing advance associated with the target non-terrestrial network device, the source non-terrestrial network device serving the first apparatus and the target non-terrestrial network device providing service to the first apparatus after the transition; and transmit, to a second apparatus prior to the transition, information about the predicted timing advance.

2. The first apparatus of claim 1, wherein the first apparatus is caused to: transition the connection from the source non-terrestrial network device to the target non-terrestrial network device without a random access procedure.

3. The first apparatus of claim 1 or claim 2, wherein the first apparatus is caused to: transmit, to the second apparatus at a first point in time prior to a time window preceding the transition, at least one of: the information, or a request for transmission of the information.

4. The first apparatus of claim 3, wherein the first apparatus is further caused to: receive, from the second apparatus, a configuration of the time window.

5. The first apparatus of any one of claims 1 to 4, wherein the first apparatus is caused to: determine that a difference between the predicted timing advance associated with the target non-terrestrial network device and a reference timing advance associated with the source non-terrestrial network device is greater than or equal to a threshold value; and based on the determination, transmit the information to the second apparatus.

6. The first apparatus of any one of claims 1 to 5, wherein the information comprises at least one of: the predicted timing advance associated with the target non-terrestrial network device, or a reference timing advance associated with the source non-terrestrial network device and a difference between the predicted timing advance and the reference timing advance.

7. The first apparatus of claim 6, wherein the predicted timing advance is carried in a medium access control control element, or the difference between the predicted timing advance and the reference timing advance is carried in at least one reserved bit in a medium access control control element, and the at least one reserved bit indicates a ratio of the difference to a predetermined timing advance difference.

8. The first apparatus of any one of claims 1 to 7, wherein the first apparatus is caused to: receive, from the second apparatus, ephemeris information of the target non-terrestrial network device and a set of timing advance parameters; and determine the predicted timing advance based on the ephemeris information and the set of timing advance parameters.

9. The first apparatus of claim 8, wherein the first apparatus is further caused to: receive, from the second apparatus, the ephemeris information and the set of timing advance parameters at a second point in time prior to a first point in time, ​ wherein at the first time point, at least one of the information or a request for transmission of the information is transmitted to the second device.

10. The first device of claim 9, wherein the first device is further caused to: receive, from the second device, a configuration of an offset of the second time point relative to the first time point.

11. A second device comprising: at least one processor; and at least one memory storing instructions that, when executed by the at least one processor, cause the second device to: receive, from a first device, information about a predicted timing advance associated with a target non-terrestrial network device before a connection is transitioned from a source non-terrestrial network device to the target non-terrestrial network device, the source non-terrestrial network device serving the first device and the target non-terrestrial network device providing service to the first device after the transition; and determine, based on the information, a configuration of a transmission time offset for transmissions of the first device.

12. The second device of claim 11, wherein the second device is caused to: receive, from the first device, at least one of the information or a request for transmission of the information at a first time point preceding a time window prior to the transition.

13. The second device of claim 12, wherein the second device is further caused to: determine the time window based on at least one of a round trip time between the first device and the second device, a number of retransmissions, or a scheduling request period; and transmit, to the first device, a configuration of the time window.

14. The second device of any one of claims 11 to 13, wherein the information comprises at least one of: the predicted timing advance associated with the target non-terrestrial network device, or a reference timing advance associated with the source non-terrestrial network device and a difference between the predicted timing advance and the reference timing advance.

15. The second device of claim 14, wherein the predicted timing advance is carried in a medium access control control element, or the difference between the predicted timing advance and the reference timing advance is carried in at least one reserved bit in a medium access control control element, and the at least one reserved bit indicates a ratio of the difference to a predetermined timing advance difference.

16. The second device of any one of claims 11 to 15, wherein the second device is caused to: transmit, to the first device, ephemeris information of the target non-terrestrial network device and a set of timing advance parameters.

17. The second device of claim 16, wherein the second device is further caused to: transmit, to the first device, the ephemeris information and the set of timing advance parameters at a second time point preceding a first time point, wherein at the first time point, at least one of the information or a request for transmission of the information is received from the first device.

18. The second device of claim 17, wherein the second device is further caused to: ​ transmitting, to the first device, a configuration of an offset of the second time point relative to the first time point.

19. The second device of any one of claims 11 to 18, wherein the second device is caused to: transmit, to the first device, the configuration of the transmission time offset.

20. The second device of any one of claims 11 to 19, wherein, the second device is connected to at least one of: the source non-terrestrial network equipment before the transition, or the target non-terrestrial network equipment, or the second device is located in at least one of: the source non-terrestrial network equipment before the transition, or the target non-terrestrial network equipment.

21. The second device of any one of claims 11 to 20, wherein non-terrestrial network equipment comprises at least one of: a satellite, or a high-altitude platform station.

22. A method comprising: determining, at a first device, a predicted timing advance associated with a target non-terrestrial network equipment before a transition of a connection from a source non-terrestrial network equipment to the target non-terrestrial network equipment, the source non-terrestrial network equipment serving the first device and the target non-terrestrial network equipment providing service to the first device after the transition; and transmitting, to a second device, information about the predicted timing advance before the transition.

23. A method comprising: receiving, at a second device, information about a predicted timing advance associated with a target non-terrestrial network equipment from a first device before a transition of a connection from a source non-terrestrial network equipment to the target non-terrestrial network equipment, the source non-terrestrial network equipment serving the first device and the target non-terrestrial network equipment providing service to the first device after the transition; and determining, based on the information, a configuration of a transmission time offset for transmissions of the first device.

24. A first device comprising: means for determining a predicted timing advance associated with a target non-terrestrial network equipment before a transition of a connection from a source non-terrestrial network equipment to the target non-terrestrial network equipment, the source non-terrestrial network equipment serving the first device and the target non-terrestrial network equipment providing service to the first device after the transition; and means for transmitting, to a second device, information about the predicted timing advance before the transition.

25. A second device comprising: means for receiving, from a first device, information about a predicted timing advance associated with a target non-terrestrial network equipment before a transition of a connection from a source non-terrestrial network equipment to the target non-terrestrial network equipment, the source non-terrestrial network equipment serving the first device and the target non-terrestrial network equipment providing service to the first device after the transition; and means for determining, based on the information, a configuration of a transmission time offset for transmissions of the first device.

26. A computer readable medium comprising instructions stored thereon for causing a device to perform at least the method of claim 22 or the method of claim 23. ​ ​ ​ ​

Images