Method and apparatus for adapting non-ground network flow for an air-to-ground network in a

Abstract

The present disclosure relates to a 5G or 6G communication system for supporting a higher data transmission rate. A user equipment (UE) for performing air-to-ground (ATG) communication with a base station, the UE including a transmitter, a receiver, and a controller configured to control the receiver to receive system information from the base station, the system information including a reference position of the base station and an altitude associated with the base station; determining a position of the UE relative to the base station based on a reference position of the base station and a height associated with the base station; and performing an event based on the location of the UE relative to the base station.

Description

Technical Field

[0001] Certain examples of this disclosure provide methods for adapting non-terrestrial network (NTN) procedures to air-to-ground (ATG) networks. For example, certain examples of this disclosure provide methods, apparatus, and systems for implementing NTN procedures in ATG networks such as 3GPP (3rd Generation Partnership Project) networks, including fifth-generation (5G) and sixth-generation (6G) networks. Background Technology

[0002] 5G mobile communication technology defines a wide frequency band, enabling high transmission speeds and new services. This can be achieved not only in "sub-6GHz" bands such as 3.5GHz, but also in "above-6GHz" bands, including 28GHz and 39GHz, which are known as millimeter waves. Furthermore, to achieve transmission speeds 50 times faster than 5G and ultra-low latency only one-tenth that of 5G, 6G mobile communication technology (referred to as "super 5G systems") is being considered in terahertz bands (e.g., the 95GHz to 3THz band).

[0003] In the early stages of 5G mobile communication technology development, standardization has been underway for the following technologies to support services related to enhanced mobile broadband (eMBB), ultra-reliable low-latency communication (URLLC), and massive machine-type communication (mMTC) and meet performance requirements: beamforming and massive MIMO for mitigating radio wave path loss and increasing radio wave transmission distance in millimeter waves; parameter set support for dynamic operation (e.g., operating multiple subcarrier spacings) for efficient utilization of millimeter wave resources and time slot formats; initial access technologies to support multi-beam transmission and broadband; definition and operation of BWP (bandwidth portion); new channel coding methods (such as LDPC (low-density parity-check) codes for large data transmissions and polar codes for highly reliable transmission of control information); L2 preprocessing; and network slicing for providing dedicated networks specifically for particular services.

[0004] Currently, given the services that 5G mobile communication technology will support, discussions are underway regarding improvements and performance enhancements to the initial 5G mobile communication technology, and physical layer standardization has been initiated for the following technologies: Vehicle-to-Everything (V2X) technology, used to assist autonomous vehicles in making driving decisions and enhance user convenience based on vehicle location and status information transmitted by vehicles; New Radio Unlicensed (NR-U) technology, designed to ensure system operation complies with various regulatory requirements in unlicensed frequency bands; NR UE power saving technology; Non-Terrestrial Network (NTN) technology, i.e., UE-satellite direct communication used to provide coverage in areas where communication with terrestrial networks is not possible; and positioning technology.

[0005] In addition, standardization of air interface architecture / protocols for the following technologies is underway: Industrial Internet of Things (IIoT) technologies to support new services through interoperability and convergence with other industries; Integrated Access and Backhaul (IAB) technologies for nodes that provide extended network service areas by comprehensively supporting wireless backhaul and access links; mobility enhancement technologies including conditional handover and DAPS (Dual Active Protocol Stack) handover; and two-step random access (NR two-step RACH) technology to simplify the random access process. Regarding system architecture / services, standardization is also underway for the following technologies: 5G baseline architectures (e.g., service-based architectures or service-based interfaces) for combining Network Functions Virtualization (NFV) and Software-Defined Networking (SDN) technologies; and mobile edge computing (MEC) for UE location-based reception services.

[0006] With the commercialization of 5G mobile communication systems, the number of connected devices will increase exponentially, necessitating enhanced functionality and performance of 5G mobile communication systems, as well as integrated operation of connected devices. To this end, new research is planned in the following areas: XR (Extended Reality) for efficient support of AR (Augmented Reality), VR (Virtual Reality), MR (Mixed Reality), etc.; 5G performance improvements and complexity reduction through the utilization of Artificial Intelligence (AI) and Machine Learning (ML); AI service support; Metaverse service support; and drone communication.

[0007] Furthermore, this development of 5G mobile communication systems will not only lay the foundation for the development of technologies such as novel waveforms for covering the terahertz band of 6G mobile communication technology, multi-antenna transmission technologies (such as full-dimensional MIMO (FD-MIMO), array antennas, and massive MIMO), metamaterial-based lenses and antennas for improving terahertz band signal coverage, high-dimensional spatial multiplexing technologies using OAM (orbital angular momentum), and RIS (reconfigurable smart surfaces), but will also lay the foundation for the development of technologies such as full-duplex technologies for improving the frequency efficiency of 6G mobile communication technology and improving system networks, AI-based communication technologies for system optimization using satellites and artificial intelligence (AI) from the design stage and for built-in end-to-end AI support, and next-generation distributed computing technologies for enabling services with complexity exceeding the operational capabilities of UEs by utilizing ultra-high-performance communication and computing resources. Summary of the Invention

[0008] Technical issues

[0009] This disclosure relates to wireless communication systems, and more specifically, to the adaptation of non-terrestrial network processes in air-to-ground networks within wireless communication.

[0010] Technical solution

[0011] Some examples of this disclosure are intended to at least partially solve, address, and / or mitigate at least one problem and / or disadvantage associated with related technologies, such as at least one problem and / or disadvantage described herein. Some examples of this disclosure are intended to provide at least one advantage over related technologies, such as at least one advantage described herein.

[0012] The adaptations provided in this disclosure to address the aforementioned deficiencies include: - The uplink synchronization validity duration is operated by not running the uplink synchronization validity timer (T430).

[0013] - Some fields of SIB19 are excluded / ignored.

[0014] - Adaptations related to location signaling and location reporting

[0015] - Adaptations related to capabilities not required by ATG

[0016] - Non-continuous coverage adaptation

[0017] - Adaptation related to AS security and base station location

[0018] According to one aspect of this disclosure, a user equipment (UE) is provided for performing air-to-ground (ATG) communication with a base station, the UE including a transmitter, a receiver, and a controller, wherein the controller is configured to control the receiver to receive system information from the base station, the system information including a reference position of the base station and an altitude associated with the base station; determine the position of the UE relative to the base station based on the reference position of the base station and the altitude associated with the base station; and perform an event based on the position of the UE relative to the base station.

[0019] In the example, the system information includes the altitude associated with neighboring base stations.

[0020] In the example, the reference location is defined based on latitude and longitude.

[0021] In the example, the event is a cell reselection event, a synchronization event, a measurement report event, or a location report.

[0022] In the example, the controller is configured to determine the three-dimensional distance between the UE and the base station based on the reference location of the base station and the height associated with the base station.

[0023] In the example, the controller is configured to send information associated with the event to the base station.

[0024] In the example, the information associated with the event includes one or more of the three-dimensional distance between the UE and the base station, the height of the UE, and the speed of the UE.

[0025] In the example, the position of the UE relative to the base station is relative to a distance threshold from a reference position of the base station, wherein the reference position is based on the reference position of the base station and the altitude associated with the base station.

[0026] According to one aspect of this disclosure, a method is provided for a user equipment (UE) to perform air-to-ground communication with a base station, the method comprising: receiving system information from the base station, the system information including a reference position of the base station and an altitude associated with the base station; determining a position of the UE relative to the base station based on the reference position of the base station and the altitude associated with the base station; and performing an event based on the position of the UE relative to the base station.

[0027] In the example, the system information includes the altitude associated with neighboring base stations.

[0028] In the example, the reference location is defined based on latitude and longitude.

[0029] In the example, the event is a cell reselection event, a synchronization event, a measurement report event, or a location report.

[0030] In the example, the method further includes determining a three-dimensional distance between the UE and the base station based on the reference location of the base station and the height associated with the base station.

[0031] In the example, the method further includes sending information associated with the event to the base station.

[0032] In the example, the information associated with the event includes one or more of the following: the three-dimensional distance between the UE and the base station, the height of the UE, and the speed of the UE.

[0033] In the example, the position of the UE relative to the base station is relative to a distance threshold from a reference position of the base station, wherein the reference position is based on the reference position of the base station and the altitude associated with the base station.

[0034] According to one aspect of this disclosure, a base station is provided for performing air-to-ground (ATG) communication with a user equipment (UE), the base station including a transmitter, a receiver, and a controller, wherein the controller is configured to control the transmitter to broadcast system information including a reference position of the base station and an altitude associated with the base station; and to control the receiver to receive from the UE information associated with events performed by the UE based on the reference position of the base station and the altitude associated with the base station.

[0035] In the example, the system information includes the altitude associated with neighboring base stations.

[0036] In the example, the reference location is defined based on latitude and longitude.

[0037] In the example, the event is a cell reselection event, a synchronization event, a measurement report event, or a location report.

[0038] In the example, the information associated with the event includes one or more of the following: the three-dimensional distance between the UE and the base station, the height of the UE, and the speed of the UE.

[0039] According to one aspect of this disclosure, a method is provided for a base station to perform air-to-ground (ATG) communication with a user equipment, the method comprising: broadcasting system information including a reference position of the base station and an altitude associated with the base station; and receiving from the UE information associated with an event performed by the UE based on the reference position of the base station and the altitude associated with the base station.

[0040] According to one aspect of this disclosure, a method for an air-to-ground (ATG) communication system is provided, the system including a base station and a user equipment (UE), the method comprising: broadcasting system information by the base station, the system information including a reference position of the base station and an altitude associated with the base station; receiving the system information by the UE; determining a position of the UE relative to the base station by the UE based on the reference position of the base station and the altitude associated with the base station; and performing an event by the UE based on the position of the UE relative to the base station.

[0041] According to one aspect of this disclosure, a method is provided performed by a user equipment (UE) in a wireless communication system, the method comprising: receiving from a base station a system information message including at least one system information block (SIB); identifying an air-to-ground (ATG) configuration based on the SIB in the at least one SIB; and performing an ATG access procedure based on the ATG configuration.

[0042] According to one aspect of this disclosure, a method is provided performed by a base station in a wireless communication system, the method comprising: identifying an air-to-ground (ATG) configuration based on a system information block (SIB); and sending a system information message including the SIB to a user equipment (UE); wherein an ATG access procedure is performed based on the ATG configuration.

[0043] According to one aspect of this disclosure, a user equipment (UE) is provided in a wireless communication system, the UE comprising: a transceiver; and a controller coupled to the transceiver, the controller being configured to: receive a system information message including at least one system information block (SIB) from a base station; identify an air-to-ground (ATG) configuration based on the SIB in the at least one SIB; and perform an ATG access procedure based on the ATG configuration.

[0044] According to one aspect of this disclosure, a base station in a wireless communication system is provided, the base station comprising: a transceiver; and a controller coupled to the transceiver, the controller being configured to: identify an air-to-ground (ATG) configuration based on a System Information Block (SIB); and send a system information message including the SIB to a User Equipment (UE); wherein an ATG access procedure is executed based on the ATG configuration.

[0045] Other aspects, advantages and distinctive features of this disclosure will become apparent to those skilled in the art from the following detailed description taken in conjunction with the accompanying drawings.

[0046] Beneficial effects

[0047] According to embodiments of this disclosure, wireless communication can be performed efficiently. In particular, the adaptation of non-terrestrial network processes for air-to-ground networks can be performed efficiently. Attached Figure Description

[0048] The embodiments / examples of this disclosure will be further described below with reference to the accompanying drawings, wherein: Figure 1 An example of a non-terrestrial network (NTN) is shown; Figure 2 An example of an air-to-ground (ATG) network is shown; Figure 3 An illustrative example of the uplink synchronization validity operation of the New Radio (NR) NTN is shown; Figure 4 An example of ephemeris synchronization operation in an Internet of Things (IoT) NTN is shown, where a) SIB31 is operating normally, b) the UE fails to read SIB31 during T318, and then T318 expires and triggers RLF; Figure 5 An example of discontinuous coverage in NTN is shown; Figure 6a An example of a UE sending coarse UE location information is shown; Figure 6b An example of an access layer (AS) security procedure is shown; Figure 7 An example of an ATG network is shown, in which an ATG cell gNB broadcasts SIB19, which contains the ephemeris of the broadcast location and a velocity component of 0. Figure 8 An example is shown where the reference positions of the two reference positions are at the same height, and b) the reference positions of the two reference positions are different. Figure 9 An example is shown where the ATG UE first obtains a rough base station location and updates the base station location after AS security is established; Figure 10 An example is shown where an ATG UE receives an ATG correction vector or full location from a terrestrial network before connecting to the ATG network; and Figure 11 A block diagram of exemplary network entities / functions that can be used in some examples of this disclosure is shown. Detailed Implementation

[0049] The following documents are cited below, and / or their contents provide context and background information that should be considered in conjunction with the following disclosures: 3GPP TS 36.304 V17.2.0 September 2022. 3GPP TS 38.331 V17.3.0 January 2023 3GPP TS 36.331 V17.4.0 March 2023 3GPP TS 36.304 V17.4.0 March 2023 3GPP TS 38.304 V17.4.0 March 2023 3GPP TS 38.331 V17.4.0 March 2023 3GPP TS 38.306 V17.4.0 March 2023 3GPP TS 37.355 V17.4.0 March 2023 RP-211557 3GPP TSG RAN meeting #91-e e-meeting, March 22 - 26th, 2021 RP-202689 3GPP TSG RAN Meeting #90 Electronic Meeting, December 7 -11, 2020 RP-211557 3GPP TSG RAN meeting #91-e e-meeting, March 22 - 26th, 2021 RP-220953 3GPP TSG RAN Meeting #95e Electronic Meeting, March 17 -23, 2022 RP-220979 3GPP TSG RAN Meeting #95e Electronic Meeting, March 17 -23, 2022 RP-222654 3GPP TSG RAN Meeting #97-e e-meeting, September 12-16, 2022 RP-221369 3GPP TSG RAN Meeting #96 Budapest, Hungary, June 6-9, 2022 LS R2-2302016 3GPP TSG-RAN WG2 Meeting # 121 Athens, Greece, February27 - March 3, 2023 R4-2303684 3GPP TSG-RAN WG4 Meeting # 106 Athens, Greece, February 27- March 3, 2022 R4-2300081 3GPP TSG-RAN WG4 Meeting # 106 Athens, Greece, February 27- March 3, 2022 (Note: The example versions shown for each TS are non-restrictive; other versions of the TS may also be considered.) Wireless or mobile (cellular) communication networks, in which mobile terminals (e.g., user equipment, such as mobile handsets) communicate with base station networks or other wireless access points or nodes via wireless links, have undergone rapid development through multiple generations. The Third Generation Partnership Project (3GPP) designs, specifies, and standardizes the technologies for mobile wireless communication networks. Fourth-generation (4G) and fifth-generation (5G) systems are now widely deployed, and the development of sixth-generation (6G) systems is underway.

[0050] The 3GPP standard for 4G systems includes the Evolved Packet Core (EPC) and Enhanced UTRAN (E-UTRAN: Enhanced Universal Terrestrial Radio Access Network). E-UTRAN uses Long Term Evolution (LTE) radio technology. LTE is generally used to refer to the entire system, including both EPC and E-UTRAN, and will be used in that sense for the remainder of this document. LTE should also be considered to include enhanced versions of LTE (such as LTE Advanced and LTE Pro), which offer increased data rates compared to LTE.

[0051] In 5G systems, a new air interface has been developed, which can be called 5G New Radio (5G NR) or simply NR. NR is designed to support a wide range of services and use cases envisioned for 5G networks, although it is built on top of existing LTE technology. As part of 5G networks, new frameworks and architectures are also being developed to expand the range of features and use cases available through 5G networks.

[0052] In recent years, non-terrestrial networks (NTN) and air-to-ground (ATG) networks have been considered, and their operation has been integrated into the 3GPP system to enhance coverage and / or provide alternative coverage mechanisms.

[0053] Non-terrestrial networks (NTN)

[0054] NR NTN (NR_NTN_Solution-Core) [RP-211557] is a 3GPP working item in 3GPP Release 17 that defines a solution to enable New Radio (NR) and NG-RAN to support NTN. It addresses a solution for transparent payloads in both geostationary and non-geostationary network scenarios, where the UE has Global Navigation Satellite System (GNSS) capabilities and the satellite beams are either geostationary or geomobile.

[0055] The Internet of Things (IoT) NTN is a 3GPP research and work item in 3GPP Release 17, designed to provide NTN access for E-UTRAN IoT devices (NB-IoT and LTE-M / eMTC) [RP-202689]. NR NTN is a work item in Rel-17, specifying adaptations that enable NR to operate on NTN [RP-211557]. NTN access can be achieved via Low Earth Orbit (LEO), Medium Earth Orbit (MEO), Geostationary Orbit (GEO), and High Altitude Platform Systems (HAPS).

[0056] Following the work items in Release 17, there are work items in Release 18 for enhanced NR NTN [RP-220953] and IoT NTN [RP-220979].

[0057] NR NTN Enhancement [RP-222654] is a 3GPP work item in 3GPP Release 18, which aims to enhance NR NTN through the following topics: - Coverage Enhancement - Identify and specify potential issues and enhancements that take into account NTN characteristics. - NR NTN deployment in frequency bands above 10 GHz - Because FR2 does not have the PRACH format for FDD, NR NTN Release 17 does not support FR2.

[0058] - UE location for network verification

[0059] - Enhanced NTN-TN and NTN-NTN mobility and service continuity

[0060] - Considering NTN-TN and NTN-NTN measurement / mobility and service continuity enhancements

[0061] Figure 1 An example of an NTN is shown, in which a gateway (GW) 106 provides a feeder link 108 to a satellite 110, and the satellite provides an NTN cell 114 and an access link 116 to devices (such as UEs) within the NTN cell. The gateway may connect to a gNB / eNB 104, which in turn connects to the core network 102. Gateway 106 may be part of, separate from, or partially integrated with the gNB / eNB 104. In some examples, some functions of the gNB / eNB may also be implemented in the satellite 110.

[0062] air-to-ground network

[0063] Air-to-ground (ATG or A2G) networks are cellular networks that provide connectivity in the air via ground-based base stations (BSs). They differ from NTNs in that the access link in ATG is from the ground to the airborne UE, whereas in NTNs, the access link is from space / sky to the ground. Figure 2 As shown, Figure 2 An example of an ATG network is shown. Figure 2 In this configuration, gNB / eNB 202 and 206 provide ATG cells 212 and 216 and connect to the core network 204. gNB / eNB 202 provides access link 208 to device 210 located within ATG cell 212. One of the primary use cases for A2G networks is providing backhaul connectivity to access points in aircraft.

[0064] In RAN4, a research project [RP-221369] was initiated in Rel-18 to define the requirements for coexistence of ATG with International Mobile Telecommunications (IMT) terrestrial networks. Additionally, the radio resource management (RRM) performance requirements for ATG UEs, the demodulation performance requirements for ATH BS / UEs, and the test procedures for ATG BS conformance testing were defined.

[0065] ATG networks are similar to NTN in some respects, namely that cells may be very large, synchronization must be different, and some network elements may move very quickly.

[0066] [RP-221369] clarifies some characteristics of ATG networks from a radio frequency (RF) perspective: - Extremely large distance between stations and wide coverage area - Deploy ATG and terrestrial networks using non-mutually exclusive frequencies - Enhanced onboard ATG terminal capabilities Synchronization operations in non-terrestrial networks Synchronization in NR NTN is partially achieved by the UE calculating the distance between the UE and the NTN node. For this, the UE needs to know its own location and the satellite's location. The UE obtains its own location via GNSS and the satellite's location via satellite ephemeris elements broadcast in the System Information (SI). Since both the UE and the satellites may move, this is maintained in two ways: 1) maintaining an accurate GNSS location, and 2) keeping the ephemeris elements of the serving satellite up-to-date.

[0067] Operations in NR NTN differ from those in IoT NTN due to the different capabilities of the NR NTN UE. NR UEs are considered more capable of performing multiple actions simultaneously. Therefore, the NR NTN UE will read system information before the uplink synchronization timer (timer T430) expires, without needing to start a separate timer if the UE fails to read SIB19. This is specified in specification 38.331 V17.3.0 below. Figure 3 As seen in the middle, Figure 3 The T430 timer associated with SIB19 is shown, which is the NRNTN uplink synchronization validity operation.

[0068] 5.2.2.4.21 Actions when receiving SIB19

[0069] Upon receiving SIB19, the UE should: 1> To start or restart the T430 in the serving cell, the timer value is set to originate from... Depend on epoch Time Indicated subframe ntn-UlSyncValidityDuration, 5.2.2.6 T430 expires UE should: 1> If the serving cell's T430 expires and is in the RRC_CONNECTED state: 2> Notification of lower-level UL synchronization loss; 2> Obtain SIB19 as defined in Clause 5.2.2.3.2; 2> After successfully obtaining SIB19: 3> Notification that lower-level UL synchronization has been achieved; In IoT NTN, the serving cell ephemeris element is sent in the system information within an element called SIB31, and this element needs to be read every time the UE connects to the IoT NTN eNB to ensure proper UE synchronization. Furthermore, a timer (T317) associated with the ephemeris element starts every time SIB31 is read; when it expires, the UE is no longer considered synchronized, and it must reacquire SIB31 to maintain synchronization. In NR NTN, the UE should ensure it has the latest ephemeris by promptly reading the SIB (SIB19 in NR). In IoT NTN, since IoT UEs (LTE-M and NB-IoT UEs) are not expected to receive system information in connected mode, the UE may tune out and may be inaccessible when reading SIB31. If the IoT NTN UE fails to read SIB31 within a timer (T318) with a configured duration, the UE performs an RLF, similar to other cases of Radio Link Failure (RLF). This operation is specified in the following specification (36.331 V17.4.0) and Figure 4 As seen in the middle, Figure 4 The T317 and T318 timers associated with the SIB31 are shown. Specifically, Figure 4 The diagram illustrates ephemeris synchronization in IoT NTN, where a) SIB31 operates normally, and b) the UE fails to read SIB31 during T318, after which T318 expires and triggers RLF.

[0070] 5.2.2.39 Received SystemInformationBlockType31 Actions during

[0071] Received SystemInformationBlockType31(SystemInformationBlockType31-NB) Afterwards, the UE should: 1> Start or restart timer T317 for a duration of [duration missing]. ul-SyncValidityDuration , from epochTime The indicated subframe begins.

[0072] 5.3.18 T317 expires

[0073] UE should: 1> If in the RRC_CONNECTED state: 2> Notification of lower-level UL synchronization loss; 2> Start timer T318; 2> Acquisition as specified in 5.2.2 SystemInformationBlockType31 (in NB-IoT) SystemInformationBlockType31-NB ); 2> Successfully obtained SystemInformationBlockType31 (in NB-IoT) SystemInformationBlockType31-NB )back: 3> Stop timer T318; 3> Notification that lower-level UL synchronization has been restored.

[0074] Note 1: SystemInformationBlockType31 (in NB-IoT) SystemInformationBlockType31-NB It can be broadcast on different narrowband or different NB-IoT carriers configured for the UE.

[0075] Note 2: The exact time of UL synchronization recovery (when obtaining...) SystemInformationBlockType31 or in NB-IoT SystemInformationBlockType31-NB (Then) the decision is made by the UE implementation, which can be derived from... epochTime The indicated subframe, and optionally in the subframe by epochTime Before the indicated subframe.

[0076] discontinuous coverage

[0077] Discontinuous coverage refers to a scenario where LEO or MEO satellite networks cannot provide continuous coverage due to insufficient satellite coverage across the entire Earth. This means that coverage will be intermittent as coverage moves. For example... Figure 5 As shown, the Reference Signal Received Power (RSRP) of each satellite 504, 506 is below the required threshold 508, and therefore cannot provide coverage to UE 502. For example, if there is only one LEO satellite, depending on the satellite coverage characteristics, the UE may only see coverage for a few minutes every 24 hours.

[0078] To conserve power when there is no coverage, the UE is allowed to power down and not perform any access stratum functions, such as measurement and cell detection attempts. To enable the UE to know when coverage is available, the network signals long-term ephemeris parameters, allowing the UE to predict satellite passage over the next few days. This is sent in the new System Information Block (SIB) SIB32. In addition to ephemeris parameters, the network also sends coverage parameters, informing the UE of the extent of coverage, to better estimate whether satellites will provide coverage.

[0079] In idle mode, many operations are based on the UE's implementation using information elements provided by the new SIB-SIB32. The idle mode specification defines the operations as follows: ---------------------------------- 36.304 V17.4.0 ---------------------------------- If received SystemInformationBlockType32 And the UE uses available satellite-aided information (e.g., currently or previously received satellite data). SystemInformationBlockType32 , SystemInformationBlockType31 Ephemeris parameters and coverage parameters in SystemInformationBlockType3 In t-Service If the system determines that the UE is outside coverage area (based on parameters such as satellite-assisted information or other parameters), the AS configuration (e.g., priority provided via dedicated signaling and recorded measurements) will be retained, but the UE will not need to perform any NTN-related idle mode tasks. The handling of running timers is determined by the UE implementation. The detection of out-of-coverage situations using satellite-assisted information is determined by the UE implementation; once the UE enters NTN coverage area, it should perform all NTN-related idle mode tasks.

[0080] ---------------------------------- 36.304 V17.4.0 ----------------------------------

[0081] SIB32

[0082] To achieve discontinuous coverage, NTNs providing discontinuous coverage use a technology called... SystemInformationBlockType32 The new SIB.

[0083] ---------------------------------- 36.331 V17.4.0 ----------------------------------

[0084] -SystemInformationBlockType32

[0085] The SystemInformationBlockType32 IE contains satellite-aided information for predicting discontinuous coverage. SystemInformationBlockType32 is transmitted only within NTN cells.

[0086] SystemInformationBlockType32 Information Element

[0087] ---------------------------------- 36.331 V17.4.0 ----------------------------------

[0088] SIB32 contains the following information elements: - SatelliteId - is used to associate the ephemeris field with the ID, so that if multiple satellites are provided and the list is updated, the UE can replace or create a new entry. - TLE Ephemeris Parameters - Provides TLE (Two-Line Element) parameters for satellite orbits, used in Earth mobile cells. - T-ServiceStart- provides the time a quasi-geostationary cell will serve the area. - footprintInfo - Provides information about the size and geometry of the satellite coverage area. - referencePoint and radius - Provide the reference point and the radius of the satellite coverage area. - elevationAngles - Used for Earth mobile cells to define coverage areas Location usage in non-terrestrial networks In the early stages of 3GPP's research on NTN, it was recognized that location could play a significant role in NTN. There are two reasons for this.

[0089] First, cells in NTN networks are often much larger than those in terrestrial networks (TN networks). The radius of an NTN cell can range from 10km to 250km, while the radius of a TN network is typically between a few hundred meters and 10km. This means that even with very low-precision UE location data, sufficient information can be provided, such as which cell the UE should connect to.

[0090] The second reason is due to the size of the area created by the satellite antenna. The satellite antenna gain is quite uniform over a large distance on the ground. This means that if the satellite is stationary and the UE moves, even if the UE moves several kilometers in any direction, as long as it is within line of sight, the path gain caused by path loss and satellite antenna gain will not change significantly. This differs from terrestrial networks, where similar movement would cause significant changes in path gain relative to the base station.

[0091] Therefore, in NTN, there are several procedures involving UE location, including: - When requested by the gNB, the UE transmits a coarse location via Radio Resource Control (RRC). This helps the gNB determine which (virtual) cell and tracking area the UE should report to the core network. This can be used... Figure 6a As seen in the text, Figure 6a This illustrates the sending of a coarse location in the UE information response 608 from UE 602 to gNB 604 when a request is made from gNB 604 to UE 602 via UE information request 606.

[0092] - Measurement reporting events based on UE location.

[0093] - Report UE location to adjust SSB measurement timing configuration (SMTC)

[0094] Access Layer (AS) Security Procedures

[0095] In the existing system, when an RRC connection is established via the RRC establishment procedure, the procedure first establishes a radio bearer that can be used for further configuration. The first radio bearer is SRB1 (Signaling Radio Bearer 1). Establishing SRB1 allows for continued UE configuration and AS security establishment. For example, configurations that can be configured without AS security include measurement reporting, MAC, and PHY configurations.

[0096] AS security is established through the initial AS security activation procedure between UE 602 and gNB 604, such as Figure 6b As shown. The initial AS security activation procedure follows the RRC establishment procedure shown by messages 650, 652, 654, and 656, which results in the establishment of SRB1 without AS security at 658. (via message...) SecurityModeCommand 660 and SecurityModeComplete 662 Establish AS security 664. SecurityModeCommand Configure the 660 to use specific security algorithms. SecurityModeComplete 662 confirms successful establishment. When the UE receives... SecurityModeCommand At 660, the UE uses a derived key to verify message integrity protection. If integrity protection passes, a new key is generated using the encryption algorithm transmitted via signaling. These keys are maintained for the SRB after the initial AS security activation is completed.

[0097] AS security supports encryption (providing confidentiality of signaling data) and integrity protection (providing integrity of user or data). AS security is supported for signaling via SRB or user data via DRB (Data Radio Bearer). The keys used for encryption and integrity protection are different for SRB and DRB, with SRB (SRB1, SRB2, SRB3, and SRB4) sharing a key (KRRCint and KRRCenc), while DRB has a separate set of keys (K...). UPint and KUPenc ).

[0098] The key can be updated, but this can only be done by using RRC reconfiguration with synchronization, which causes the UE to respond... RRCReconfigurationComplete Random access is performed before the message.

[0099] System Information

[0100] SIB19 is the System Information Block (SIB) of the NTN. SIB19 is crucial for the UE to connect to the NTN cell. This is because SIB19 contains ephemeris and common timing advance (TA). The ephemeris is used by the UE to calculate its satellite position, which, together with the common TA, is used to calculate the delay to the satellite, which is required for synchronization.

[0101] In an ATG network, the situation differs from that of a normal NTN. In an ATG network, the base station is on the ground, while the UE is at high altitude. Therefore, the base station will be stationary, while the UE moves very quickly. In LS R2-2302016 / R4-2303684, RAN4 queries whether SIB19 can be simplified for ATG: RAN4 agrees that ATG UEs require time and / or frequency compensation. The ATG BS should provide location information to assist in UE-based time and / or frequency pre-compensation. Signaling for BS location can utilize the IE in TS38.331. EphemerisInfo (As defined for NTN SIB19). RAN4 also does not exclude other solutions that provide ATG BS location information.

[0102] From RAN4's perspective, assuming SIB19 content is reused for ATG, the BS should broadcast... EphemerisInfo To ensure that UEs relying on SIB ephemeris information for frequency / time pre-compensation can receive ATG BS locations. Note that the ATG network will operate on the TN band; example bands discussed in RAN4 include... n1 , n77 and n79 .

[0103] RAN4 requests RAN2 to check whether SIB19 can be applied to ATG, and if not, whether an alternative can be applied to provide the ATG BS location to the ATG UE from RAN2's perspective.

[0104] Reusing procedures developed for NTN for ATG would be advantageous. In NTN, the UE resolves frequency and timing issues by self-synchronizing using its own location (through GNSS measurements) and the satellite's location (through ephemeris acquisition). In an ATG network, the network can broadcast only one location in SIB19, using positionVelocity-r17 with the velocity component set to 0, such as... Figure 7As shown, the gNB / eNB 702 providing ATG cell 710 sends SIB19712 to UE 708 via access link 706. However, using certain aspects in an ATG network would be overly complex.

[0105] In addition, other processes and NTN-related capabilities may need to be adjusted or changed when connecting to an ATG network.

[0106] In [R4-2300081] "Discussion on general aspects of ATG UE RF, RAN4#106, Qualcomm, March 2023", the following statement is made regarding ATG SIB19: In addition, this may have RAN2 specification implications for the SIB19 reception procedure of the ATG UE, since the ATG UE may not need to maintain T430.

[0107] However, the above does not explain how the UE may not maintain T430, since current requirements for NTN UEs include acquiring SIB19 and initiating T430. This disclosure addresses this issue and other deficiencies in the NTN process for ATG networks.

[0108] The following description of examples of this disclosure, taken in conjunction with the accompanying drawings, is intended to aid in a comprehensive understanding of certain examples of this disclosure. This description includes various specific details to aid understanding, but these should be considered exemplary only. Therefore, those skilled in the art will recognize that various changes and modifications can be made to the examples described herein without departing from the scope of the invention or disclosure.

[0109] Identical or similar components may be indicated by the same or similar reference numerals, although they may be shown in different figures.

[0110] For the sake of clarity and brevity, and to avoid obscuring the subject matter of this disclosure, detailed descriptions of techniques, structures, constructions, functions, or processes known in the art will be omitted.

[0111] The terms and words used herein are not limited to their bibliographical or standard meanings, but are used solely to ensure clarity and consistency in understanding this disclosure.

[0112] Throughout this description, the words “including,” “comprising,” and “containing,” and their variations, such as “including” and “containing,” mean “including but not limited to” and are not intended to exclude other features, elements, components, integers, steps, processes, operations, functions, characteristics, properties, and / or groups thereof.

[0113] Throughout this description, singular forms (such as "a," "a kind," and "the") encompass plural forms unless the context requires otherwise. For example, a reference to "object" includes a reference to one or more such objects.

[0114] Throughout this specification, the expressions “at least one A, B and / or C” (or similar expressions) and “one or more A, B and / or C” (or similar expressions) shall be regarded as including all possible combinations, such as: A, B, C, A and B, A and C, A and B and C.

[0115] Throughout this description, the expression “X for Y” (where Y is some action, process, operation, function, activity or step, and X is some means for performing that action, process, operation, function, activity or step) covers means X adapted, configured or arranged specifically (but not necessarily uniquely) to perform Y.

[0116] Features, elements, components, integers, steps, processes, operations, functions, characteristics, attributes, and / or groups thereof described or disclosed in connection with a particular aspect, embodiment, or example should be understood to be applicable to any other aspect, embodiment, or example described herein, unless incompatible therewith.

[0117] The following examples apply to 3GPP 4G (e.g., LTE) and / or 5G (e.g., NR) and use the associated terminology. However, those skilled in the art will understand that the techniques disclosed herein are not limited to these examples or 3GPP 4G (e.g., LTE) and / or 5G (e.g., NR) and can be applied to any suitable system or standard, such as one or more existing and / or future generations of wireless communication systems or standards (e.g., B5G, 5G-Advanced, 6G, etc.). Those skilled in the art will understand that the techniques disclosed herein can be applied to any existing or future versions of 3GPP 4G (e.g., LTE) and / or 5G (e.g., NR) and / or 5G Advanced and / or 6G, and / or (3GPP Release 17, 18, 19, 20, etc.) or any other relevant standards. For example, the functionality and other characteristics of the various network entities disclosed herein can be applied to corresponding or equivalent entities or characteristics in other communication systems or standards. Corresponding or equivalent entities or characteristics can be considered as entities or characteristics performing the same or similar roles, functions, operations, or purposes within the network.

[0118] In addition, the following also apply to this disclosure: - The terms function / use case / configuration / scenario / site are used interchangeably.

[0119] - The terms "model" and "model function" are used interchangeably.

[0120] - This disclosure also applies to non-3GPP entities.

[0121] - The concepts, proposals, solutions, methods, embodiments, figures and / or examples presented in this disclosure are applicable to various types of communication systems, such as 4G, 4G-Advanced, 5G, 5G-Advanced and 6G.

[0122] A specific network entity can be implemented as a network element on dedicated hardware, a software instance running on dedicated hardware, and / or a virtualization function instantiated on a suitable platform (such as cloud infrastructure).

[0123] Those skilled in the art will understand that this disclosure is not limited to the specific examples disclosed herein. For example: - The technologies disclosed in this article are not limited to 3GPP 4G or 5G or 5G-Advanced, but also applicable to B5G and 6G systems.

[0124] - One or more entities in the examples disclosed herein may be replaced by one or more alternative entities that perform equivalent or corresponding functions, procedures, or operations.

[0125] - One or more messages in the examples disclosed herein may be replaced by one or more alternative messages, signals or other types of information carriers that convey equivalent or corresponding information.

[0126] - You may add one or more additional elements, entities, and / or messages to the examples published in this article.

[0127] - In some examples, one or more unnecessary elements, entities, and / or messages may be omitted.

[0128] - The functionality, process, or operation of a specific entity in one example can be assigned to two or more separate entities in an alternative example.

[0129] - The functions, procedures, or operations of two or more separate entities in one example can be performed by a single entity in an alternative example.

[0130] - The information carried by a particular message in one example can be carried by two or more separate messages in an alternative example.

[0131] - Information carried by two or more separate messages in one example can be carried by a single message in an alternative example.

[0132] - In alternative examples, the order of operations can be modified if possible.

[0133] - Information transmission between network entities is not limited to the specific form, type, and / or message order described in the published examples.

[0134] Some examples of this disclosure may be provided in the form of an apparatus / device / network entity and / or methods thereof configured to perform one or more defined network functions. Such an apparatus / device / network entity may include one or more elements, such as one or more receivers, transmitters, transceivers, processors, controllers, modules, units, etc., each element configured to perform one or more corresponding process, operation, and / or method steps to implement the techniques described herein. For example, operation / function of X may be performed by a module (or X module) configured to perform X. Some examples of this disclosure may be provided in the form of a system (e.g., a network) and / or methods thereof comprising one or more such apparatus / device / network entities.

[0135] Non-terrestrial network process adaptation

[0136] This disclosure provides a method for adapting SIB19 content and NTN operation to ATG networks. SIB19 content and NTN operation are typically used in NTNs, where the base station components are in satellites and subsequently move (the gNB in ​​an NTN is on the ground, but the UE is synchronized with the satellite). In an ATG network, the UE needs to be synchronized with a stationary terrestrial network.

[0137] In this disclosure, the concepts of ATG network and network are used interchangeably. In other words, "network" should not be understood to refer to a non-ATG network.

[0138] Regarding base stations, the concept of gNB is interchangeable with BS / eNB / NG-RAN / NG-eNB or similar concepts. This also means that the methods in this disclosure can be applied not only to 5G NR but also to 4G E-UTRAN, including IoT technologies such as eMTC or NB-IoT. Therefore, it is applicable to IoT NTN based on 4G E-UTRAN.

[0139] Regarding wireless devices, ATG UE and UE can refer to the same type of wireless device. In other words, "UE" should not be understood as referring to "non-ATG UE".

[0140] SIB19 and Uplink Synchronization Validity Operations

[0141] In one example, the UE will not perform the same uplink synchronization operation as in the NTN. The advantage of this is that it eliminates the need for continuous acquisition of the SIB19; for example, it can be acquired only once, and synchronization can be performed based on a single received SIB19 instance. This simplifies the synchronization implementation of the ATG.

[0142] This can be achieved in the following ways: Network signaling: The application has an unlimited uplink synchronization validity period (example in Example 1 below). - This can be achieved by the network sending infinite values ​​via signals, or - In an ATG network, the UE can be configured to apply unlimited values, so values ​​transmitted with or without signals will be ignored, or - If the uplink synchronization validity period is not signaled for the serving cell, the application has an unlimited value for uplink synchronization validity. Network signaling: Signaling does not require reacquiring the SIB19 flag (unless it has already been signaled), for example, the signaling can be in the SIB19 itself.

[0143] - This can be the flag ul-SyncNotRequired.

[0144] UE behavior: UEs connected to an ATG cell or ATG network can automatically assume that they do not need to reacquire SIB19.

[0145] - The UE can know whether it is an ATG cell or network based on identifiers in system information (such as SIB1). It can also know implicitly based on the frequency band implemented or used.

[0146] - The UE may not initiate T430 in an ATG cell, but only acquire SIB19 when connecting to an ATG cell. This example can be seen in Example 2 below.

[0147] This simplifies the process.

[0148] - The ATG UE will synchronize once upon connection, and then, since the timer has not expired, the ATG UE will never be considered out of sync. When the ATG UE performs a handover, the UE may not start the T430 timer.

[0149] - As long as the ATG UE reads SIB19 before connecting to the NTN, the ATG UE will always be considered synchronized.

[0150] - ATG UE does not need to reread SIB19 during recovery or reconstruction.

[0151] In one example, the NTN ephemeris is not sent in SIB19. Instead, an ATG reference position is sent for synchronization purposes. This reference position is used as a synchronization point and can be read continuously.

[0152] The above example can also be applied to synchronization operations in IoT NTN, thus using SIB31 and timer T317.

[0153] In summary, in the above example, SIB19 is broadcast by the gNB / eNB and received by the UE. The content of SIB19 can be adapted and / or the behavior of the UE can be adapted. Compared to NTN, the adaptation of UE behavior can be achieved through network signaling and / or predefined changes to UE operations related to the ATG network.

[0154] Fields sent in ATG SIB19

[0155] In an ATG network, there are several information elements that may not be needed and therefore may not need to be sent or received, or may not exist for the ATG NTN: - epochTime - This field can be ignored. - ntn-UlSyncValidityDuration - As explained above, may not exist in ATG NTN.

[0156] - ta-Info - Since the synchronization point will be on the ground, this field may not exist or may be ignored in the ATG network.

[0157] Therefore, in one example, the ATG gNB is configured to exclude one or more of the aforementioned information elements. Alternatively, one or more of these fields / information elements may still be included in the SIB19 broadcast by the gNB, and / or set to arbitrary values, thus being received by the UE but subsequently ignored by the UE when performing and / or updating synchronization or other SIB-based operations.

[0158] Location-based operations - location configuration includes altitude

[0159] In NTN, the UE is considered to be on the ground. However, in ATG networks, the UE will be in the air, while the BS is on the ground. In many procedures (such as measurement reports), a reference location relative to the UE's location is typically used, but this reference location is defined as a point on the Earth's surface.

[0160] -----------------------38.331 V17.4.0---------------------

[0161] -ReferrenceLocation

[0162] IE ReferenceLocation It contains location information used as a reference location. The value of this field is consistent with that defined in TS37.355

[49] . Ellipsoid-Point Same. The first / leftmost bit of the first octet contains the most significant bit.

[0163] ReferenceLocation information element

[0164] --ASN1START

[0165] --TAG-REFERENCELOCATION-START

[0166] ReferenceLocation-r17 ::=OCTET STRING

[0167] -- TAG-REFERENCELOCATION-STOP

[0168] --ASN1STOP

[0169] -----------------------38.331 V17.4.0---------------------

[0170] -----------------------37.355 V17.4.0----------------------

[0171] -Ellipsoid-Point

[0172] IE Ellipsoid-Point Used to describe the geographic shape defined in TS 23.032

[15] .

[0173] -- ASN1START

[0174] Ellipsoid-Point ::= SEQUENCE {

[0175] latitudeSignENUMERATED (north, south), degreesLatitudeINTEGER (0..8388607),--23 bit field degreesLongitudeINTEGER (-8388608..8388607)--24 bit field } -- ASN1STOP -----------------------37.355 V17.4.0---------------------- In one example, position is defined by altitude to define a reference position in the air, as shown in Implementation Example 4 below. Each BS can have a different altitude, therefore each BS will indicate a different altitude in its SIB.

[0176] In another example, a default altitude is configured for all reference locations. This can be configured, for example, in SIB19. Typical values ​​are, for example, 30,000 feet or 10,000 meters – optimized for the aviation field.

[0177] By adding the height above, all relevant reference locations can be interpreted as having a configured height. This can lead to improved UE location determination compared to cell location.

[0178] Location-based operations - 3D distance

[0179] Some procedures use two-dimensional distance (measurement report events CondEventD1 and RRC idle / inactive distance-based cell reselection method, using distance thresholds and reference locations) (3GPP 38.331 V17.4.0, 3GPP TS 38.304 V17.4.0) to evaluate whether certain actions should be performed. In one example, three-dimensional distance is used to make the procedure work in an ATG network. This can be configured as follows: - Indicates that three-dimensional distance markers should be used in the assessment; for example, this could be found in NTN SIB, SIB19. - If a reference position with altitude is sent, the ATG UE assumes that three-dimensional distance should be used. - ATG UE always uses three-dimensional distance For conditional handover events, the reference location can be at the same altitude or transmitted separately. The same altitude is meaningful in some networks where it is expected that all cells will have the same location. Both options are available... Figure 8 As seen in the diagram, in a), ATG cells 802 and 804 have the same height, while in b), ATG cells 806 and 808 have separate / different heights, namely reference position height 1 and reference position height 2.

[0180] Location reporting in ATG network

[0181] In one example, when an ATG UE sends a measurement report, it includes altitude in the location element. This is important because altitude is less noticeable in an ATG network than in an NTN network, and the location may be useful to the network. The network can use this to determine which cell the ATG UE should connect to, i.e., whether mobility is required, or to update the UE's location to the core network, etc.

[0182] In addition to location and altitude, the ATG UE can be configured to report uncertainties such as latitude, longitude, and altitude. Furthermore, the UE can be configured to report vertical and / or latitude / longitude velocities. In another example, these parameters can be reported at different granularities (e.g., coarse or fine) or accuracy levels (e.g., low, medium, or high).

[0183] For example, when the UE is in an ATG network, the ATG UE can autonomously include altitude in its response to requests. This means that when the UE receives a coarseLocationRequest in the UEInformationRequest, the UE responds not only with coarseLocationInfo, but also with altitude such as coarseAltitude.

[0184] Since NTN UEs are configured to report coarse location information (where the coarse location is approximate in both longitude and latitude), a similar approach should be adopted if the UE reports a coarse location using altitude. For example, this could be a coarseness of a few hundred meters, making it more difficult to accurately determine the location of ATG UEs.

[0185] In another related example, the UE can be configured to report location information at a higher granularity (or finer granularity or detailed location information). The UE's location reporting can be done using... Figure 6a The process shown in the diagram has been adapted as described above.

[0186] In any of the examples, figures, and descriptions above, the network may require user consent to obtain any information reported from the ATG UE. This may be implemented as part of the ATG UE subscription information, configured in the network (e.g., in the RAN or CN), for example through the network operator or OAM, or based on regional policies, or based on any supplementary information from internal and / or external network entities or functions.

[0187] In another example, the ATG UE can provide user consent to the network.

[0188] Enhanced coarse location reporting can be accomplished using UEInformationRequest / UEInformationResponse or RRC measurement reports.

[0189] ATG discontinuous coverage

[0190] The technology used for NTN discontinuous coverage can be used in ATG UEs to know when ATG UEs will have available coverage.

[0191] In one example, the ATG network broadcasts elements related to discontinuous coverage to provide coverage-related information, indicating when coverage is available. Since discontinuous coverage information, typically applicable to satellites, involves satellite orbits (ephemeris elements), several adaptations are possible: - Broadcasting fixed positions instead of ephemeris elements - Include altitude in location-based configurations This means that coverage can be described using an altitude parameter. For example, if coverage is only provided at altitudes up to 5000 meters, this will be sent and taken into account by the ATG UE when measuring and / or attempting to connect to the ATG UE. Capabilities and other supported NTN features ATG UE can be based on NTN UE but simplified, that is, some features required by NTN may not be required by ATG UE (TS 38.306 V17.4.0).

[0192] In one example, one such feature that the ATG UE may not support is service link propagation delay compensation. The gNB uses this feature to adjust the measurement timing window via the feature serviceLinkPropDelayDiffReporting.

[0193] In another example, another feature that the ATG UE may not support is parallelMeasurementGap. This feature introduces two parallel measurement gaps to track measurements from neighboring satellite cells.

[0194] In another example, another feature that the ATG UE may not support is the parallelSMTC feature. That is, the ATG UE does not need to implement parallel SMTC for its operations.

[0195] ATG capabilities can be sent individually or based on NTN, with exceptions to the above conditions.

[0196] In another example, ntn-ScenarioSupport is not included in the ATG UE, but is included in separate ATG scenario support, which may lead to some of the conditions mentioned above. For example, if the UE transmits support for nonTerrestrialNetwork and atg-Support but not ntn-ScenarioSupport, then some NTN features are not applicable to the ATG UE.

[0197] Even if the UE supports both ATG and NTN scenarios, the gNB can still employ certain features in the ATG network. This reduces the amount of testing required to implement these features.

[0198] In the example, the UE can report its support for ATG operations to the network in its UE capabilities. In one example, the UE reports the new capability using a new IE (such as the ATGCapability IE or any other appropriate name).

[0199] In another embodiment, UE ATG capabilities may be included (or stored) by the network in the UE context.

[0200] Secure ATG Network Location Reporting

[0201] Base station locations are generally considered sensitive (i.e., security) information, making their reporting / providing a sensitive process. Regarding NTN, a UE may require the location of NTN nodes (i.e., satellites or HAPS) for synchronization, thus location information can be broadcast as part of system information. However, in NTN, the satellites or HAPS providing connectivity are typically high in the air and move very quickly. Due to this rapid movement and synchronization requirements, broadcasting the location of NTN nodes (i.e., network nodes) is considered acceptable. In ATG networks, a UE may also need the location of (ATG) base stations for synchronization with the associated gNB, which can be achieved by the ATG gNB broadcasting its base station location using NTN signaling. However, since base station locations are stationary and on the ground, this location information is more sensitive and should ideally not be exposed in broadcast information while still allowing synchronization.

[0202] In this disclosure, base station location information refers to the physical location (i.e., physical transmission point) of the base station communicating with the UE, while ATG gNB refers to the logical entity performing communication with the UE. Therefore, although the location of an ATG (or ordinary) gNB may be the same as the location of its associated base station, this is not always the case. In some cases, reference may be made to the (ATG) gNB location or synchronization point location, which refers to the physical location of the transmission point from the (ATG) gNB, i.e., the physical location of its associated base station. Furthermore, mentioning an ATG UE refers to a UE with ATG communication capabilities, but simply mentioning a UE does not preclude the UE from having ATG communication capabilities.

[0203] One method to allow base stations to maintain synchronization without revealing their location is to "fake" their locations within a certain proportion or within a specific tolerance range—that is, intentionally providing imprecise or lower-precision locations. For example, if a base station is located at x1, y1, z1, additional vectors xS, yS, zS can be added to form the broadcast location, where this additional vector is smaller than the location vector, for example, in the range of 1 to 100 meters, although it can take any suitable size smaller or larger than this. Alternatively, the network (i.e., ATG gNB) can broadcast base station locations with reduced accuracy or granularity, or increased coarsening. However, the challenge lies in striking a balance between synchronization and network anonymity and security. For example, a less precise broadcast location might hinder synchronization but improve network anonymity and security, and vice versa.

[0204] According to the examples in this disclosure, a network broadcasts a spoofed location (i.e., an intentionally inaccurate / uncertain location), and then provides an authenticated UE that has established AS security with another, more accurate location (or a location with higher accuracy, higher granularity, or more detailed information). This achieves a better balance between synchronization and security by allowing initial synchronization based on broadcast information that does not reveal the precise location of the base station, while allowing the authenticated UE to access the precise location for more accurate synchronization and subsequently operate as if the precise location of the base station had been initially provided.

[0205] Figure 9 An example RRC establishment and AS security procedure is provided, which is based on a base station location spoofed by the relevant ATG gNB 904 broadcast, and then updates the ATG UE 902 with more accurate location information after AS security is established.

[0206] At 906, the ATG gNB broadcasts its location information (the location information of its associated base station) in the system information with lower precision, and the ATG UE receives this system information. For example, the ATG UE in RRC idle or RRC inactive mode obtains the broadcast base station location (using system information, such as periodically and / or on demand, using existing and / or newly defined SIBs).

[0207] At 908, the ATG UE synchronizes with the ATG gNB using reduced-precision location information and performs RRC establishment via random access to establish SRB1 without AS security (see also). Figure 6b (650-658).

[0208] At 912, the ATG UE performs an AS security procedure to establish AS security with the ATG gNB at 914 (see also...). Figure 6b (660-664).

[0209] After AS security is established, at point 916, the ATG UE receives a more precise location (or a more accurate, more granular, or more detailed location) from the base station via dedicated signaling / messages (e.g., existing and / or newly defined RRC messages / signaling). Further communication with the ATG gNB (e.g., user plane data transmission 918) or selected further communication can then be performed based on this more precise location.

[0210] In some examples, Figure 9 The process may include the network (e.g., an ATG gNB) notifying the ATG UE that a higher-precision or more detailed location is available. This indication could be, for example, a 1 / 0 flag ('1 / 0' = high-precision location available / unavailable). highAccuracyPosition IE={1,0} Or any other suitable name. The ATG UE can then send, request, or otherwise receive a more precise location. This indication can be provided before or after AS security is established.

[0211] In some examples, the network may provide different granularities of location accuracy to different types of ATG UEs, such as based on the UE's subscription, and / or other information on the network and / or the ATG UE, such as UE capabilities.

[0212] In some examples, the ATG UE is configured (e.g., by network configuration) to request the detailed location (or higher accuracy location) of the base station after AS security is established. This request can be configured as a default request or issued in response to an indication (e.g., a flag) that higher accuracy location information is available. For example, the ATG UE can check a flag. highAccuracyPosition IE={1,0} The flag can be broadcast (e.g., periodically and / or on demand via system information, using existing and / or newly defined SIBs) and / or as a dedicated RRC signaling / message (e.g., existing and / or newly defined), and the ATG UE accordingly requests detailed location information.

[0213] In another example, an ATG UE may request information related to the availability of the base station's precise location before, during, and / or after AS secure establishment. Such a request can be issued by including flags (or indications or requests) in any existing and / or newly defined RRC messages / signaling. Examples include RRCSetupRequest, RRCSetupComplete, RRCResumeRequest, RRCResumeComplete, RRCReestablishmentRequest, RRCReestablishmentComplete, or RRCReconfigurationComplete, and / or any other suitable RRC message.

[0214] In another example, the network can configure the ATG UE's access to the precise location of a base station, even if the access to the information is configurable. For example, based on UE capabilities, subscriptions, and / or other information. For instance, the AMF can determine whether a particular ATG UE is allowed access to the detailed base station location. Permission to access precise location information can be sent to the ATG gNB, which then transmits the precise location. This can be done, for example, using existing and / or new signaling / messages / IEs on the NG interface. Alternatively, it can be done using any UE context management procedure.

[0215] If access is controlled by the AMF, the AMF may decide to deny the UE's request for a detailed base station location after verifying whether the ATG UE is permitted or not to access detailed (or more precise) base station locations. Optionally, the AMF may provide a new denial reason value, such as detailedgNBLocationNotAllowed / Supported and / or any other suitable naming. Access verification may be based on subscription information obtained from Unified Data Management (UDM) and / or on other ancillary information from the network, such as information obtained from the Network Data Analysis Function (NWDAF) and / or the ATG gNB.

[0216] In another example, if an ATG UE's request for base station location information with higher accuracy (or different granularity) is rejected (or fails), the network may release the ATG UE. This could be achieved, for example, using a UE context release request (initiated by the NG-RAN node) or UE context release (initiated by the AMF) procedure / message, RRC signaling / message, and / or newly defined signaling and / or messages.

[0217] In another example, the gNB can verify an ATG UE's request for detailed (or more accurate or precise) base station location information and accept or reject the request. This includes, for example, a reason value for rejecting or failing to share the information, such as `detailedgNBLocationNotAllowed / Supported` and / or any other suitable naming.

[0218] In another example, the UE may obtain (or request) more accurate base station locations from other network entities (and / or functions), such as from the Location Management Function (LMF), i.e., via the LTE Location Protocol (LPP).

[0219] In another example, the gNB provides more accurate (or more detailed) location information for the base station based on instructions from the AMF (and / or any other network entity and / or network function).

[0220] As Figure 9A variation of the approach allows the network to transmit more precise location information as long as the ATG UE is in connected mode. Therefore, it may not be necessary to establish AS security before transmitting the more precise location information.

[0221] In another example, higher-precision information, or information used to derive that information, can be broadcast but in encrypted form, making it accessible only to ATG UEs configured with the appropriate keys. For instance, both lower-precision and higher-precision information (or information required to derive the higher-precision information, such as correction vectors or functions) can be included in the broadcast system information, but the higher-precision information is encrypted, making access to it controlled by the network's encryption key distribution. The encryption key can be configured and distributed by the network and can have validity based on, for example, time or location. The encryption key can be provided by an ATG gNB associated with the higher-precision location information or by another gNB or ATG gNB. In this approach, access to the higher-precision information can be obtained before or after AS security is established, depending on the key distribution.

[0222] The actual data for more precise location information can be provided in different ways. For example, the complete (or at least higher) precision location information can be sent, or a correction to the lower precision location information can be sent, which can take many different forms, such as a function or quantitative adjustment.

[0223] The complete location information provides higher precision; for example, it may have greater granularity than a coarse location, or it may be a more precise value that more accurately represents the true location of the base station.

[0224] Regarding corrections for lower-precision position information, a correction vector including x, y, and z components can be provided. If the position is randomized only in x and y, the correction vector may contain only x and y components. This correction vector can be generated through addition (e.g., P...). Synch conn mode =P broadcasted +P correction ) or subtraction (e.g., P) Synch conn mode =P broadcasted -P correction )application.

[0225] Regarding how the ATG UE applies this higher-precision location or correction, the ATG UE may apply it only to base station locations traversed while in connected mode, or when the ATG UE is in connected mode with the ATG gNB. The correction (rather than precise location) may also be applied to multiple base station locations over time. For example, this may be applied to multiple base stations as the aircraft moves within the ATG network while the ATG UE is connected and receiving the correction. The time associated with the correction may be configured with the correction, or it may be hard-coded. For example, the correction may be applied to one or more base stations for a full 24 hours. Outside of this time, a coarse base station location may still be available for limited connectivity. Alternatively, the correction may be updated more frequently, either by receiving new corrections or by the correction being a function of time or other parameters.

[0226] In another example, one or more base station location corrections can be applied to the locations of neighboring cell base stations for measurement purposes.

[0227] As can be seen from the above examples, providing correction for lower-precision positions, rather than just providing higher-precision positions, can lead to a variety of alternatives and expanded use cases.

[0228] Regarding signaling, correction or precise location can be configured by the ATG gNB via the following example RRC message.

[0229] - RRCReconfiguration message - see Example 5

[0230] This may contain elements representing corrections. In the case of carrier aggregation or dual connectivity operations in ATG, corrections can be per cell or per group of cells.

[0231] - Dedicated to sending new RRC messages for corrected / precise location

[0232] Based on the example of ATG UEs requesting correction from the network, such a request can be executed by including a flag in any RRC message. Suitable messages include -Complete class messages, such as... RRCSetupComplete , RRCResumeComplete , RRCReestablishmentComplete or RRCReconfigurationComplete .

[0233] To help maintain the security of base station locations, broadcast locations can change over time. For example, a broadcast location can be changed every 24 hours. This means that correction vectors also need to be updated periodically and / or re-provided with more accurate locations.

[0234] Figure 10Another method for providing higher-precision location information is illustrated, either through correction or by providing complete location information. Specifically, information about the higher-precision location is provided to the UE before it attempts to synchronize with the ATG network. This can be achieved, for example, by using alternatives such as OAM or by configuring a correction vector (or complete location information) for the ATG UE via the core network. This can be configured via the terrestrial network, for example, before the ATG UE begins connecting to the ATG network. The correction vector can be applied to the broadcast location before synchronization and random access are performed. A request to receive the correction vector can be sent to the gNB or the terrestrial core network. Sending the correction vector can also be initiated by the terrestrial network before the UE enters the ATG network.

[0235] For example, this information can be provided before synchronization with the ATG gNB. For instance, if the ATG UE is an aircraft, the correction vector can be received when the UE connects to the ground network before takeoff. This would allow for larger "spoofing" or coarse positioning, such as possible deviations of several hundred meters. In some cases, the ground network may know information about the ATG gNBs / base stations the UE is expected to encounter and provide correction vectors / precise locations for multiple ATG gNBs.

[0236] refer to Figure 10 At point 1008, UE 1000 may request an ATG correction vector / complete location from its connected terrestrial network 1006. The terrestrial network may then send the ATG correction vector / complete location to the UE at point 1010. Subsequently, the RRC establishment procedure with ATG gNB 1002 (illustrated by 1014) may be based on the complete location received from the terrestrial network, or the RRC establishment procedure 1014 may be based on low-precision broadcast location information corrected using the correction vector received from the terrestrial network. User plane transmission 1016 can then be performed with the ATG gNB as normal.

[0237] Although the description primarily concerns ATG networks (i.e., ATG UEs and ATG gNBs), the aforementioned base station location obfuscation method is also applicable to other network types, such as NTNs, where it may be necessary to hide network nodes to some extent in certain scenarios. For example, in NTNs, competitors may obtain broadcast ephemeris data to infer how satellite constellations are used or how satellite stations are maintained. This method can also be applied to terrestrial networks.

[0238] The adaptation of the procedures performed by the UE and gNB / eNB for the ATG network, as well as the adaptation of the data sent and received by the UE and gNB / eNB for the ATG network, described above can be combined in any combination. Furthermore, new information formats can be included in any suitable form, such as information elements, messages, and / or system information blocks. Any example data that is not required by the ATG network compared to NTN can be ignored by the UE and / or gNB / eNB, omitted from transmission, or set to arbitrary values.

[0239] The adaptation of the procedures performed by the UE and gNB / eNB for the ATG network, as well as the adaptation of the data sent and received by the UE and gNB / eNB for the ATG network, can be achieved by the UE, gNB, or a combination of these entities. Alternatively, existing procedures and signaling described in the aforementioned reference standards can be used, but their information content must be adapted as described above.

[0240] 3GPP specification modification examples

[0241] Based on the above examples, the following provides exemplary additions / adaptations that can be introduced into 3GPP specifications, where the highlighted portions represent some additions / adaptations.

[0242] Example 1

[0243] -----------------------38.331 V17.4.0 Example------------------------

[0244] 5.2.2.4.21 Actions when receiving SIB19

[0245] After receiving SIB19, the UE in the RRC_CONNECTED state should: 1> For UEs in an ATG network: 2> To start or restart the T430 for the serving cell, the timer value is set to the serving cell's value. infinity ; 1> Otherwise: 2> To start or restart the T430 in the serving cell, the timer value is set to the source. epochTime The serving cell of the indicated subframe ntn-UlSyncValidityDuration ; Note: For NTN, the UE should attempt to... ntn-UlSyncValidityDuration and epochTime The instruction duration is reacquired via UE before it expires. SIB19 .

[0246] ------------------------38.331 V17.4.0 Example------------------------

[0247] Example 2

[0248] ------------------------38.331 V17.4.0 Example------------------------

[0249] 5.2.2.4.21 Actions when receiving SIB19

[0250] After receiving SIB19, the UE in the RRC_CONNECTED state should: 1> If the UE is not an ATG UE or is not connected to an ATG cell: 2> To start or restart the T430 in the serving cell, the timer value is set to the source. epochTime The serving cell of the indicated subframe ntn-UlSyncValidityDuration ; Note: The UE should attempt to use the following method: ntn-UlSyncValidityDuration and epochTime The instruction duration is reacquired via UE before it expires. SIB19 .

[0251] <omitted>

[0252] 5.3.5.5.2 Reconfiguration with Synchronization

[0253] The UE should perform the following actions to perform a reconfiguration with synchronization.

[0254] 1> If AS security is not activated, then perform the action to enter the RRC IDLE state as specified in 5.3.11, with the release reason being "other", after which the process ends; 1> If it is running, stop timer T430; 1> If the UE is not an ATG UE or is connected to an ATG cell, then timer T430 is started according to the target cell NTN configuration, and the timer value is set to ntn-UlSyncValidityDuration of the subframe indicated by epochTime.

[0255] ------------------------38.331 V17.4.0 Example------------------------

[0256] Example 3

[0257] ------------------------38.331 V17.4.0 Example------------------------

[0258] - NTN-Config

[0259] IE NTN-Config provides the parameters required for a UE to access NR via NTN access.

[0260] NTN-Config Information Elements

[0261] ------------------------38.331 V17.4.0 Example------------------------

[0262] Example 4

[0263] ------------------------38.331 V17.4.0 Example------------------------

[0264] - SIB 19

[0265] SIB 19 contains satellite auxiliary information for NTN access.

[0266] SIB 19 Information Elements

[0267] ------------------------38.331 V17.4.0 Example------------------------

[0268] Example 5

[0269] ------------------------38.331 V17.4.0 Example------------------------

[0270] - RRCReconfiguration

[0271] RRCReconfiguration The message is a command to modify the RRC connection. It can convey information for measurement configuration, mobility control, radio resource configuration (including RB, MAC master configuration, and physical channel configuration), and AS security configuration.

[0272] Signaling radio bearer: SRB1 or SRB3

[0273] RLC-SAP: AM

[0274] Logical Channel: DCCH

[0275] Direction: Network to UE

[0276] ------------------------38.331 V17.4.0 Example------------------------

[0277] It will be understood that the examples of this disclosure may be implemented in hardware, software, or a combination of hardware and software. Certain examples of this disclosure may provide a computer program comprising instructions or code that, when executed, implements a method, system, and / or apparatus according to any aspect, example, and / or embodiment of this disclosure. Certain embodiments of this disclosure provide a machine-readable storage for storing such a program.

[0278] Figure 11 Block diagrams of exemplary network entities / functions that can be used in the examples of this disclosure are shown, such as the disclosed technologies associated with any of the foregoing figures. For example, any network entity, network function, etc. (e.g., UE, BS, gNB / eNB, ATG entity) can... Figure 11 The network entities shown are provided in the form of network entities. Those skilled in the art will understand that network entities / functions may be implemented, for example, as network elements on dedicated hardware, software instances running on dedicated hardware, and / or virtualization functions instantiated on a suitable platform (e.g., cloud infrastructure).

[0279] Entity 1100 includes a processor (or controller) 1101, a transmitter 1103, and a receiver 1105. Receiver 1105 is configured to receive one or more messages from one or more other network entities, as described above. Transmitter 1103 is configured to send one or more messages to one or more other network entities, as described above. Processor 1101 is configured to perform one or more operations, as described above.

[0280] It will be understood that in each example / implementation / aspect, etc., described above, one or more features or operations may be omitted, modified, or moved (e.g., the order of features or operations may be changed) if needed and appropriate.

[0281] Furthermore, the accompanying diagrams illustrating the example method flow include text regarding specific steps / operations, which will be understood to be merely examples of the corresponding steps / operations, where more general definitions (e.g., those found in the description of the corresponding step) may apply to that step / operation.

[0282] Furthermore, regarding all of the foregoing, one or more features or operations from any example / embodiment may be combined with features or operations from any other example / embodiment. That is, this disclosure should be considered to include all combinations of the examples / embodiments disclosed herein (where appropriate), as well as combinations of the various features within and between each example / embodiment (where appropriate).

[0283] The techniques described herein can be implemented using any suitably configured apparatus and / or system. Such apparatus and / or system can be configured to perform methods according to any aspect, embodiment, or example disclosed herein. Such apparatus may include one or more elements, such as one or more receivers, transmitters, transceivers, processors, controllers, modules, units, etc., each element configured to perform one or more corresponding process, operation, and / or method steps to implement the techniques described herein. For example, operation / function of X may be performed by a module (or X module) configured to perform X. One or more elements may be implemented in hardware, software, or any combination of hardware and software.

[0284] It will be understood that the examples of this disclosure may be implemented in the form of hardware, software, or a combination of hardware and software. Any such software may be stored in the form of volatile or non-volatile storage, such as storage devices like ROM (whether erasable or rewritable), or memories like RAM, memory chips, devices, or integrated circuits, or on optically or magnetically readable media like CDs, DVDs, disks, or magnetic tapes.

[0285] It will be understood that storage devices and storage media are machine-readable storage suitable for storing programs or certain examples of programs of this disclosure containing instructions that, when executed, implement certain examples of this disclosure. Therefore, certain examples provide programs comprising code for implementing methods, apparatus, or systems according to any example, embodiment, and / or aspect of this disclosure, and machine-readable storage for storing such programs. Furthermore, such programs can be electronically transmitted via any medium, such as communication signals carried over a wired or wireless connection.

[0286] Although this disclosure has been shown and described with reference to certain examples thereof, those skilled in the art will understand that various changes in form and detail may be made without departing from the scope of this disclosure.

[0287] The reader’s attention is directed to all documents and files that were filed at the same time as or before this application and made publicly available together with this specification, and the contents of all such documents and files are incorporated herein by reference.

[0288] Acronyms and Definitions

[0289] 3GPP: Third Generation Partnership Project

[0290] 5G: Fifth Generation

[0291] 5GC: 5G Core Network

[0292] 5QI: 5G Quality of Service Identifier

[0293] 5GS: 5G system

[0294] 5GSM: 5G System Session Management

[0295] 5GMM: 5G System Mobility Management

[0296] AF: Application Functions

[0297] AI: Artificial Intelligence

[0298] AM: Confirmation Mode

[0299] AMF: Access and Mobility Management Function

[0300] AS: Access Layer

[0301] ASP: Application Service Provider

[0302] ATG: Air-to-Ground

[0303] AUSF: Authentication Server Function

[0304] CDN: Content Delivery Network

[0305] DCAF: Data Collection Application Functionality

[0306] DNAI: Data Network Access Identifier

[0307] DNN: Data Network Name

[0308] DNS: Domain Name Server

[0309] DRB: Data Radio Bearer

[0310] eNB: Evolved Node B

[0311] EPC: Evolved Packet Core

[0312] FEC: Forward Error Correction

[0313] FQDN: Fully Qualified Domain Name

[0314] GBR: Guaranteed Bit Rate

[0315] gNB: Next-Generation Node B

[0316] GPSI: General Public Subscription Identifier

[0317] HSS: Home Subscriber Server

[0318] IAB: Integrated Access and Backhaul

[0319] ID: Identity / Identifier

[0320] IIoT: Industrial Internet of Things

[0321] IMEI: International Mobile Equipment Identity

[0322] IP: Internet Protocol

[0323] I-SMF: Intermediate Session Management Function

[0324] LADN: Local Area Network Data Network

[0325] LL SSM: Lower-level SSM

[0326] MBMS: Multimedia Broadcast / Multicast Service

[0327] MBS: Multicast / Broadcast Service

[0328] MBSF: Multicast / Broadcast Service Function

[0329] MBSTF: Multicast / Broadcast Service Transmission Function

[0330] MB-SMF: Multicast / Broadcast Session Management Function

[0331] MB-UPF: Multicast / Broadcast User Plane Functions

[0332] ML: Machine Learning

[0333] MME: Mobility Management Entity

[0334] MN: Master Node

[0335] MNF: Monitoring Network Functions

[0336] MNO: Mobile Network Operator

[0337] MT: Mobile terminal

[0338] NAS: Non-Access Layer

[0339] NEF: Network Open Functionality

[0340] NRF: Network Storage Function

[0341] NG-RAN: Next Generation Radio Access Network

[0342] NG-eNB: Next-Generation eNB

[0343] NSA: Non-Standalone Networking

[0344] NSSF: Network Slice Selection Function

[0345] NTN: Non-terrestrial network

[0346] NW: Network

[0347] NWDAF: Network Data Analysis Function

[0348] OS: Operating System

[0349] OSAPP: Operating System Application

[0350] PCF: Policy Control Function

[0351] PCO: Protocol Configuration Options

[0352] PDR: Group Detection Rules

[0353] PDU: Protocol Data Unit

[0354] PTM: Point-to-Multipoint

[0355] PTP: Point-to-Point

[0356] QFI: Quality of Service Flow Identifier (ID)

[0357] QoS: Quality of Service

[0358] RACH: Random Access Channel

[0359] RAN: Radio Access Network

[0360] RRC: Radio Resource Control

[0361] RSD: Route Descriptor

[0362] SA: Standalone Network

[0363] SDAP: Service Data Adaptation Protocol

[0364] SDU: Service Data Unit

[0365] SGW: Service Gateway

[0366] SIM: User Identification Module

[0367] SLA: Service Level Agreement

[0368] SM: Session Management

[0369] SMF: Session Management Function

[0370] SN: Secondary node

[0371] S-NSSAI: Auxiliary Information for Single Network Slice Selection

[0372] SSB: Synchronization Signal Block

[0373] SSM: Source-Specific IP Multicast Address

[0374] SSC: Session and Service Continuity

[0375] SRB: Signaling Radio Bearer

[0376] SUPI: Subscription Permanent Identifier

[0377] TA: Tracking Area

[0378] TAI: Tracking Area Marker

[0379] TE: Terminal Equipment

[0380] TM: Transparent Mode

[0381] TMGI: Temporary Mobility Group Identifier

[0382] TS: Technical Specification

[0383] UAV: Unmanned Aerial Vehicle

[0384] UDM: Unified Data Management

[0385] UDR: Unified Data Repository

[0386] UE: User Equipment

[0387] UL: Uplink

[0388] UM: Unconfirmed Mode

[0389] UP: User Interface

[0390] UPF: User-Face Functionality

[0391] URLLC: Ultra-Reliable Low-Latency Communication

[0392] URSP: UE Routing Policy

Claims

1. A method performed by a user equipment (UE) in a wireless communication system, the method comprising: Receive system information messages from the base station, including at least one System Information Block (SIB); Based on the SIB in the at least one SIB, identify the air-to-ground ATG configuration; as well as Based on the ATG configuration, the ATG access process is executed.

2. The method according to claim 1, in, The ATG configuration includes the height of the base station used for the ATG access procedure.

3. The method according to claim 1, in, The ATG configuration includes the location of the base station used for the ATG access procedure.

4. The method according to claim 1, further comprising: The location of the UE is determined based on the ATG configuration.

5. A method performed by a base station in a wireless communication system, the method comprising: Based on the System Information Block (SIB), identify the air-to-ground ATG configuration; as well as Send a system information message including the SIB to the user equipment (UE); The ATG access process is executed based on the ATG configuration.

6. The method according to claim 5, in, The ATG configuration includes the height of the base station used for the ATG access procedure.

7. The method according to claim 5, in, The ATG configuration includes the location of the base station used for the ATG access procedure.

8. The method according to claim 5, in, The location of the UE is determined based on the ATG configuration.

9. A user equipment (UE) in a wireless communication system, the UE comprising: transceiver; as well as The controller, coupled to the transceiver, is configured as follows: Receive system information messages from the base station, including at least one System Information Block (SIB); Based on the SIBs in at least one of the SIBs, identify the air-to-ground ATG configuration; and Based on the ATG configuration, the ATG access process is executed.

10. The UE according to claim 9, in, The ATG configuration includes the height of the base station used for the ATG access procedure.

11. The UE according to claim 9, in, The ATG configuration includes the location of the base station used for the ATG access procedure.

12. The UE of claim 9, wherein the controller is further configured to: The location of the UE is determined based on the ATG configuration.

13. A base station in a wireless communication system, the base station comprising: transceiver; as well as The controller, coupled to the transceiver, is configured as follows: Based on the System Information Block (SIB), identify the air-to-ground ATG configuration; as well as Send a system information message including the SIB to the user equipment (UE); The ATG access process is executed based on the ATG configuration.

14. The base station according to claim 13, in, The ATG configuration includes the height of the base station used for the ATG access procedure.

15. The base station according to claim 13, in, The ATG configuration includes the location of the base station used for the ATG access procedure, and The location of the UE is determined based on the ATG configuration.

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