Field

[0001] The subject matter disclosed herein relates generally to the field of resolving geometrical limitations for positioning determination in a wireless communication network. This document defines a first network node, a method in a first network node, a second network node, and a method in the second network node.

Introduction

[0002] The conclusions of 3GPP TR 38.882 vl8.0.0 identified the need to define a network-based solution which aims at verifying reported UE location information. In Rel-18 the Network Induced Location Reporting (NI-LR) procedure has been adopted for Non-Terrestrial Networks (NTN) to verify reported UE location information. The positioning techniques in 3GPP are developed by considering typical scenarios in terrestrial networks, where measurements from at least three gNBs are usually used for location estimates. However, such scenarios may be hard to find in NTNs as one of the common scenarios in NTN is that the UEs are usually in the coverage area of a single non-terrestrial network node. The non-terrestrial network node may be a satellite. Therefore, the existing positioning methods may need to be adapted in cases where the UE is located in the coverage area of a single satellite. A simple adaptation may comprise a time-based method, whereby the movement of NGSO satellites is used by performing multiple location measurements at multiple time instances from the same satellite. Each measurement will be taken when the satellite is in a different position and thus a plurality of measurements allow an estimate of the UE location to be determined. However, such methodology may result in some limitations and there is a possibility of low accuracy location estimates.

Summary

[0003] A problem with location estimates derived from measurements taken by a single non-terrestrial network node is that of the mirror ambiguity problem. By way of example, where the non-terrestrial network node is a satellite, the mirror ambiguity problem exists because measurements are taken from single satellite orbital plane at multiple time instances, where intersection of these measurements may be formed at two points, resulting in two location estimates of the same UE.

[0004] Disclosed herein are procedures for resolving geometrical limitations for positioning determination in a wireless communication network. Said procedures may be implemented by a first network node, a method in a first network node, a second network node, and a method in the second network node.

[0005] Accordingly, there is provided a first network node comprising a processor and a memory coupled with the processor, the processor configured to cause the first network node to: receive a device location request configuration message from a second network node, wherein the device location configuration message comprises a request for an indication of a location estimate for the device; determine a first location estimate of the device by transmitting, from a non-terrestrial network node, a first positioning configuration message to the device; determine that the accuracy of the first location estimate does not meet a network location verification accuracy requirement; determine that the first location estimate is within a threshold distance of the ground track of the non-terrestrial network node; and transmit a location information response message to the second network node, wherein the location information response message includes an indication that the first location estimate is within a threshold distance of the ground track of the non-terrestrial network node.

[0006] There is further provided a method performed by a first network node, the method comprising: receiving a device location request configuration message from a second network node, wherein the device location configuration message comprises a request for an indication of a location estimate for the device; determining a first location estimate of the device by transmitting, from a non-terrestrial network node, a first positioning configuration message to the device; determining that the accuracy of the first location estimate does not meet a network location verification accuracy requirement; determining that the first location estimate is within a threshold distance of the ground track of the non-terrestrial network node; and transmitting a location information response message to the second network node, wherein the location information response message includes an indication that the first location estimate is within a threshold distance of the ground track of the non-terrestrial network node.

[0007] There is further provided a second network node comprising a processor; and a memory coupled with the processor, the processor configured to cause the second network node to: transmit a device location request configuration message to a first network node, wherein the device location configuration message comprises a request for an indication of a location estimate for the device; and receive a location information response message from the first network node, wherein the location information response message includes an indication that the first location estimate is within a threshold distance of the ground track of the non-terrestrial network node.

[0008] There is further provided a method of a second network node, the method comprising: transmitting a device location request configuration message to a first network node, wherein the device location configuration message comprises a request for an indication of a location estimate for the device; and receiving a location information response message from the first network node, wherein the location information response message includes an indication that the first location estimate is within a threshold distance of the ground track of the non-terrestrial network node.

Brief description of the drawings

[0009] In order to describe the manner in which advantages and features of the disclosure can be obtained, a description of the disclosure is rendered by reference to certain apparatus and methods which are illustrated in the appended drawings. Each of these drawings depict only certain aspects of the disclosure and are not therefore to be considered to be limiting of its scope. The drawings may have been simplified for clarity and are not necessarily drawn to scale.

[0010] Methods and apparatus for resolving geometrical limitations for positioning determination in a wireless communication network will now be described, byway of example only, with reference to the accompanying drawings, in which:

Figure 1 depicts an embodiment of a wireless communication system for resolving geometrical limitations for positioning determination in a wireless communication network;

Figure 2 depicts a user equipment apparatus that may be used for implementing the methods described herein;

Figure 3 depicts further details of the network node that may be used for implementing the methods described herein;

Figure 4 illustrates an example of positioning measurements and reference signals for determining the location of a wireless communication device in a terrestrial wireless communication network; Figure 5 shows the architecture in 5GS applicable to positioning of a UE with NR or E-UTRA access;

Figure 6 illustrates Location Service Support by NG-RAN which may include RAN-UE Positioning Operations;

Figure 7 illustrates an NG-RAN Location Reporting Procedure;

Figure 8 illustrates a transparent satellite based NG-RAN architecture;

Figure 9 illustrates an architecture comprising a regenerative satellite without Inter-Satellite Links (ISL) and with a gNB processed payload;

Figure 10 illustrates an architecture comprising a regenerative satellite with ISL and a gNB processed payload;

Figure 11 is an example illustration of technical limitation of position accuracy for time based methods with single satellite node;

Figure 12 illustrates NLLR procedure to verify the UE location;

Figure 13 illustrates a method comprising additional messaging in NLLR to determine the cause of inaccurate location estimates;

Figure 14 illustrates an example of beam Layout of beam layout with FRF=3 to resolve geometrical limitations of time-based methods;

Figure 15 illustrates a method performed by a first network node; and Figure 16 illustrates a method performed by a second network node.

Detailed description

[0011] As will be appreciated by one skilled in the art, aspects of this disclosure may be embodied as a system, apparatus, method, or program product. Accordingly, arrangements described herein may be implemented in an entirely hardware form, an entirely software form (including firmware, resident software, micro-code, etc.) or a form combining software and hardware aspects.

[0012] For example, the disclosed methods and apparatus may be implemented as a hardware circuit comprising custom very-large-scale integration (“VLSI”) circuits or gate arrays, off-the-shelf semiconductors such as logic chips, transistors, or other discrete components. The disclosed methods and apparatus may also be implemented in programmable hardware devices such as field programmable gate arrays, programmable array logic, programmable logic devices, or the like. As another example, the disclosed methods and apparatus may include one or more physical or logical blocks of executable code which may, for instance, be organized as an object, procedure, or function. [0013] Furthermore, the methods and apparatus may take the form of a program product embodied in one or more computer readable storage devices storing machine readable code, computer readable code, and/ or program code, referred hereafter as code. The storage devices may be tangible, non-transitory, and/or non-transmission. The storage devices may not embody signals. In certain arrangements, the storage devices only employ signals for accessing code.

[0014] Any combination of one or more computer readable medium may be utilized. The computer readable medium may be a computer readable storage medium. The computer readable storage medium may be a storage device storing the code. The storage device may be, for example, but not limited to, an electronic, magnetic, optical, electromagnetic, infrared, holographic, micromechanical, or semiconductor system, apparatus, or device, or any suitable combination of the foregoing.

[0015] More specific examples (a non-exhaustive list) of the storage device would include the following: an electrical connection having one or more wires, a portable computer diskette, a hard disk, a random-access memory (“RAM”), a read-only memory (“ROM”), an erasable programmable read-only memory (“EPROM” or Flash memory), a portable compact disc read-only memory (“CD-ROM”), an optical storage device, a magnetic storage device, or any suitable combination of the foregoing. In the context of this document, a computer readable storage medium may be any tangible medium that can contain, or store, a program for use by or in connection with an instruction execution system, apparatus, or device.

[0016] Reference throughout this specification to an example of a particular method or apparatus, or similar language, means that a particular feature, structure, or characteristic described in connection with that example is included in at least one implementation of the method and apparatus described herein. Thus, reference to features of an example of a particular method or apparatus, or similar language, may, but do not necessarily, all refer to the same example, but mean “one or more but not all examples” unless expressly specified otherwise. The terms “including”, “comprising”, “having”, and variations thereof, mean “including but not limited to”, unless expressly specified otherwise. An enumerated listing of items does not imply that any or all of the items are mutually exclusive, unless expressly specified otherwise. The terms “a”, “an”, and “the” also refer to “one or more”, unless expressly specified otherwise.

[0017] As used herein, a list with a conjunction of “and/ or” includes any single item in the list or a combination of items in the list. For example, a list of A, B and/ or C includes only A, only B, only C, a combination of A and B, a combination of B and C, a combination of A and C or a combination of A, B and C. As used herein, a list using the terminology “one or more of’ includes any single item in the list or a combination of items in the list. For example, one or more of A, B and C includes only A, only B, only C, a combination of A and B, a combination of B and C, a combination of A and C or a combination of A, B and C. As used herein, a list using the terminology “one of’ includes one, and only one, of any single item in the list. For example, “one of A, B and C” includes only A, only B or only C and excludes combinations of A, B and C. As used herein, “a member selected from the group consisting of A, B, and C” includes one and only one of A, B, or C, and excludes combinations of A, B, and C.” As used herein, “a member selected from the group consisting of A, B, and C and combinations thereof’ includes only A, only B, only C, a combination of A and B, a combination of B and C, a combination of A and C or a combination of A, B and C.

[0018] Furthermore, the described features, structures, or characteristics described herein may be combined in any suitable manner. In the following description, numerous specific details are provided, such as examples of programming, software modules, user selections, network transactions, database queries, database structures, hardware modules, hardware circuits, hardware chips, etc., to provide a thorough understanding of the disclosure. One skilled in the relevant art will recognize, however, that the disclosed methods and apparatus may be practiced without one or more of the specific details, or with other methods, components, materials, and so forth. In other instances, well- known structures, materials, or operations are not shown or described in detail to avoid obscuring aspects of the disclosure.

[0019] Aspects of the disclosed method and apparatus are described below with reference to schematic flowchart diagrams and/or schematic block diagrams of methods, apparatuses, systems, and program products. It will be understood that each block of the schematic flowchart diagrams and/or schematic block diagrams, and combinations of blocks in the schematic flowchart diagrams and/or schematic block diagrams, can be implemented by code. This code may be provided to a processor of a general-purpose computer, special purpose computer, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, create means for implementing the functions /acts specified in the schematic flowchart diagrams and/or schematic block diagrams. [0020] The code may also be stored in a storage device that can direct a computer, other programmable data processing apparatus, or other devices to function in a particular manner, such that the instructions stored in the storage device produce an article of manufacture including instructions which implement the function/ act specified in the schematic flowchart diagrams and/or schematic block diagrams.

[0021] The code may also be loaded onto a computer, other programmable data processing apparatus, or other devices to cause a series of operational steps to be performed on the computer, other programmable apparatus, or other devices to produce a computer implemented process such that the code which executes on the computer or other programmable apparatus provides processes for implementing the functions /acts specified in the schematic flowchart diagrams and/or schematic block diagram.

[0022] The schematic flowchart diagrams and/ or schematic block diagrams in the Figures illustrate the architecture, functionality, and operation of possible implementations of apparatuses, systems, methods, and program products. In this regard, each block in the schematic flowchart diagrams and/ or schematic block diagrams may represent a module, segment, or portion of code, which includes one or more executable instructions of the code for implementing the specified logical function(s). [0023] It should also be noted that, in some alternative implementations, the functions noted in the block may occur out of the order noted in the Figures. For example, two blocks shown in succession may, in fact, be executed substantially concurrently, or the blocks may sometimes be executed in the reverse order, depending upon the functionality involved. Other steps and methods may be conceived that are equivalent in function, logic, or effect to one or more blocks, or portions thereof, of the illustrated Figures.

[0024] The description of elements in each figure may refer to elements of proceeding Figures. Like numbers refer to like elements in all Figures.

[0025] Figure 1 depicts an embodiment of a wireless communication system 100 for resolving geometrical limitations for positioning determination in a wireless communication network. The wireless communication network may comprise a nonterrestrial network. The wireless communication system 100 includes at least one remote unit 105, a radio access network (“RAN”) 120, and a mobile core network 140. The RAN 120 and the mobile core network 140 form a mobile communication network. The RAN 120 may be composed of a base unit 121 with which the remote unit 105 communicates via a satellite 129 using wireless communication links, e.g., service link(s) 125 and feeder link(s) 127. As depicted, the mobile communication network includes an “on-ground” base unit 121 and non-terrestrial network (“NTN”) gateway 123 which serves the remote unit 105 via satellite access.

[0026] Even though a specific number of remote units 105, base units 121, wireless communication links, RANs 120, satellites 129, NTN gateways 123 (e.g., satellite ground/ earth devices), and mobile core networks 140 are depicted in Figure 1, one of skill in the art will recognize that any number of remote units 105, base units 121, wireless communication links, RANs 120, satellites 129, NTN gateways 123, and mobile core networks 140 may be included in the wireless communication system 100.

[0027] In one implementation, the RAN 120 is compliant with the 5G system specified in the Third Generation Partnership Project (“3GPP”) specifications. For example, the RAN 120 may be a New Generation Radio Access Network (“NG-RAN”), implementing NR RAT and/ or 3GPP Long-Term Evolution (“LTE”) RAT. In another example, the RAN 120 may include non-3GPP RAT (e.g., Wi-Fi® or Institute of Electrical and Electronics Engineers (“IEEE”) 802.11 -family compliant WLAN). In another implementation, the RAN 120 is compliant with the LTE system specified in the 3GPP specifications. More generally, however, the wireless communication system 100 may implement some other open or proprietary communication network, for example Worldwide Interoperability for Microwave Access (“WiMAX”) or IEEE 802.16-family standards, among other networks. The present disclosure is not intended to be limited to the implementation of any particular wireless communication system architecture or protocol.

[0028] In one embodiment, the remote units 105 may include computing devices, such as desktop computers, laptop computers, personal digital assistants (“PDAs”), tablet computers, smart phones, smart televisions (e.g., televisions connected to the Internet), smart appliances (e.g., appliances connected to the Internet), set-top boxes, game consoles, security systems (including security cameras), vehicle on-board computers, network devices (e.g., routers, switches, modems), or the like. In some embodiments, the remote units 105 include wearable devices, such as smartwatches, fitness bands, optical head-mounted displays, or the like. Moreover, the remote units 105 may be referred to as the UEs, subscriber units, mobiles, mobile stations, users, terminals, mobile terminals, fixed terminals, subscriber stations, user terminals, wireless transmit/ receive unit (“WTRU”), a device, or by other terminology used in the art. In various embodiments, the remote unit 105 includes a subscriber identity and/or identification module (“SIM”) and the mobile equipment (“ME”) providing mobile termination functions (e.g., radio transmission, handover, speech encoding and decoding, error detection and correction, signaling and access to the SIM). In certain embodiments, the remote unit 105 may include a terminal equipment (“TE”) and/ or be embedded in an appliance or device (e.g., a computing device, as described above).

[0029] The remote units 105 may communicate directly with one or more of the base units 121 in the RAN 120 via uplink (“UL”) and downlink (“DL”) communication signals. In some embodiments, the remote units 105 communicate in a non-terrestrial network via UL and DL communication signals between the remote unit 105 and a satellite 129. In certain embodiments, the satellite 129 may communicate with the RAN 120 via an NTN gateway 123 using UL and DL communication signals between the satellite 129 and the NTN gateway 123. The NTN gateway 123 may communicate directly with the base units 121 in the RAN 120 to relay UL and DL communication signals.

[0030] Furthermore, the UL and DL communication signals may be carried over the wireless communication links during at least a portion of their path between RAN 120 and the remote unit 105. In the depicted embodiment, the wireless communication link between the remote unit 105 and satellite 129 comprises a service link 125, while the wireless communication link between the satellite 129 and the base unit 121 comprises a feeder link 127. However, in other embodiments, the satellite(s) and NTN gateways may be deployed between the base unit 121 or RAN 120 and the mobile core network 140, e.g., similar to wireless backhaul links.

[0031] The RAN 120 is an intermediate network that provides the remote units 105 with access to the mobile core network 140. In various embodiments, the UL communication signals may comprise one or more uplink channels, such as the Physical Uplink Control Channel (“PUCCH”) and/or Physical Uplink Shared Channel (“P USCH”), while the DL communication signals may comprise one or more downlink channels, such as the Physical Downlink Control Channel (“PDCCH”) and/or Physical Downlink Shared Channel (“PDSCH”).

[0032] Moreover, the satellite 129 provides a non-terrestrial network allowing the remote unit 105 to access the mobile core network 140 via satellite access. While Figure 1 depicts a transparent NTN system where the satellite 129 repeats the waveform signal for the base unit 121, in other embodiments the satellite 129 (for regenerative NTN system), or the NTN gateway 123 (for alternative implementation of transparent NTN system) may also act as base station, depending on the deployed configuration.

[0033] In some embodiments, the remote units 105 communicate with an application server via a network connection with the mobile core network 130. For example, an application 107 (e.g., web browser, media client, telephone and/or Voice-over-Internet- Protocol (“VoIP”) application) in a remote unit 105 may trigger the remote unit 105 to establish a protocol data unit (“PDU”) session (or other data connection) with the mobile core network 130 via the RAN 120. The mobile core network 130 then relays traffic between the remote unit 105 and the application server (e.g., the content server 151 in the packet data network 150) using the PDU session. The PDU session represents a logical connection between the remote unit 105 and the User Plane Function (“UPF”) 131.

[0034] To establish the PDU session (or PDN connection), the remote unit 105 must be registered with the mobile core network 130 (also referred to as “attached to the mobile core network” in the context of a Fourth Generation (“4G”) system). Note that the remote unit 105 may establish one or more PDU sessions (or other data connections) with the mobile core network 130. As such, the remote unit 105 may have at least one PDU session for communicating with the packet data network 150, e.g., representative of the Internet. The remote unit 105 may establish additional PDU sessions for communicating with other data networks and/ or other communication peers.

[0035] In the context of a 5G system (“5GS”), the term “PDU Session” a data connection that provides end-to-end (“E2E”) user plane (“UP”) connectivity between the remote unit 105 and a specific Data Network (“DN”) through the UPF 131. A PDU Session supports one or more Quality of Service (“QoS”) Flows. In certain embodiments, there may be a one-to-one mapping between a QoS Flow and a QoS profile, such that all packets belonging to a specific QoS Flow have the same 5G QoS Identifier (“5QI”).

[0036] In the context of a 4G/LTE system, such as the Evolved Packet System (“EPS”), a Packet Data Network (“PDN”) connection (also referred to as EPS session) provides E2E UP connectivity between the remote unit and a PDN. The PDN connectivity procedure establishes an EPS Bearer, i.e., a tunnel between the remote unit 105 and a Packet Gateway (“PGW”, not shown) in the mobile core network 130. In certain embodiments, there is a one-to-one mapping between an EPS Bearer and a QoS profile, such that all packets belonging to a specific EPS Bearer have the same QoS Class Identifier (“QCI”).

[0037] The base units 121 may be distributed over a geographic region. In certain embodiments, a base unit 121 may also be referred to as an access terminal, an access point, a base, a base station, a Node-B (“NB”), an Evolved Node B (abbreviated as eNodeB or “eNB,” also known as Evolved Universal Terrestrial Radio Access Network (“E-UTRAN”) Node B), a 5G/NR Node B (“gNB”), a Home Node-B, a relay node, a RAN node, or by any other terminology used in the art. The base units 121 are generally part of a RAN, such as the RAN 120, that may include one or more controllers communicably coupled to one or more corresponding base units 121. These and other elements of radio access network are not illustrated but are well known generally by those having ordinary skill in the art. The base units 121 connect to the mobile core network 130 via the RAN 120. Note that in the NTN scenario, certain RAN entities or functions may be incorporated into the satellite 129. For example, the satellite 129 may be an embodiment of a Non-Terrestrial base station/base unit.

[0038] The base units 121 may serve a number of remote units 105 within a serving area, for example, a cell or a cell sector, via a wireless communication link 123. The base units 121 may communicate directly with one or more of the remote units 105 via communication signals. Generally, the base units 121 transmit DL communication signals to serve the remote units 105 in the time, frequency, and/or spatial domain. Furthermore, the DL communication signals may be carried over the wireless communication links 123. The wireless communication links 123 may be any suitable carrier in licensed or unlicensed radio spectrum. The wireless communication links 123 facilitate communication between one or more of the remote units 105 and/or one or more of the base units 121. Note that during NR-U operation, the base unit 121 and the remote unit 105 communicate over unlicensed radio spectrum.

[0039] In one embodiment, the mobile core network 130 is a 5GC or an Evolved Packet Core (“EPC”), which may be coupled to a packet data network 150, like the Internet and private data networks, among other data networks. A remote unit 105 may have a subscription or other account with the mobile core network 130. Each mobile core network 130 belongs to a single public land mobile network (“PLMN”). The present disclosure is not intended to be limited to the implementation of any particular wireless communication system architecture or protocol. [0040] The mobile core network 130 includes several network functions (“NFs”). As depicted, the mobile core network 130 includes at least one UPF 131. The mobile core network 130 also includes multiple control plane (“CP”) functions including, but not limited to, an Access and Mobility Management Function (“AMF”) 133 that serves the RAN 120, a Session Management Function (“SMF”) 135, a Network Exposure Function (“NEF”), a Policy Control Function (“PCF”) 137, a Location Management Function (“LMF”) 141, a Unified Data Management function (“UDM”) and a User Data Repository (“UDR”) 139.

[0041] The UPF(s) 131 is responsible for packet routing and forwarding, packet inspection, QoS handling, and external PDU session for interconnecting Data Network (“DN”), in the 5G architecture. The AMF 133 is responsible for termination of NAS signaling, NAS ciphering & integrity protection, registration management, connection management, mobility management, access authentication and authorization, security context management. The SMF 135 is responsible for session management (i.e., session establishment, modification, release), remote unit (i.e., UE) IP address allocation & management, DL data notification, and traffic steering configuration for UPF for proper traffic routing.

[0042] The NEF is responsible for making network data and resources easily accessible to customers and network partners. Service providers may activate new capabilities and expose them through APIs. These APIs allow third-party authorized applications to monitor and configure the network’s behavior for a number of different subscribers (i.e., connected devices with different applications). The PCF 137 is responsible for unified policy framework, providing policy rules to CP functions, access subscription information for policy decisions in UDR.

[0043] The LMF 141, in one embodiment, receives positioning measurements or estimates from RAN 120 and the remote unit 105 (e.g., via the AMF 133) and computes the position of the remote unit 105. The UDM 139 is responsible for generation of Authentication and Key Agreement (“AKA”) credentials, user identification handling, access authorization, subscription management. The UDR is a repository of subscriber information and can be used to service a number of network functions. For example, the UDR may store subscription data, policy-related data, subscriber-related data that is permitted to be exposed to third party applications, and the like. In some embodiments, the UDM is co-located with the UDR, depicted as combined entity “UDM/UDR” 139. [0044] In various embodiments, the mobile core network 130 may also include an Authentication Server Function (“AUSF”) (which acts as an authentication server), a Network Repository Function (“NRF”) (which provides NF service registration and discovery, enabling NFs to identify appropriate services in one another and communicate with each other over Application Programming Interfaces (“APIs”)), or other NFs defined for the 5GC. In certain embodiments, the mobile core network 130 may include an authentication, authorization, and accounting (“AAA”) server.

[0045] In various embodiments, the mobile core network 130 supports different types of mobile data connections and different types of network slices, wherein each mobile data connection utilizes a specific network slice. Here, a “network slice” refers to a portion of the mobile core network 130 optimized for a certain traffic type or communication service. A network instance may be identified by a single-network slice selection assistance information (“S-NSSAI,”) while a set of network slices for which the remote unit 105 is authorized to use is identified by network slice selection assistance information (“NSSAI”).

[0046] Here, “NSSAI” refers to a vector value including one or more S-NSSAI values. In certain embodiments, the various network slices may include separate instances of network functions, such as the SMF 135 and UPF 131. In some embodiments, the different network slices may share some common network functions, such as the AMF 133. The different network slices are not shown in Figure 1 for ease of illustration, but their support is assumed. Where different network slices are deployed, the mobile core network 130 may include a Network Slice Selection Function (“NSSF”) which is responsible for selecting of the Network Slice instances to serve the remote unit 105, determining the allowed NSSAI, determining the AMF set to be used to serve the remote unit 105.

[0047] Although specific numbers and types of network functions are depicted in Figure 1, one of skill in the art will recognize that any number and type of network functions may be included in the mobile core network 130. Moreover, in an LTE variant where the mobile core network 130 comprises an EPC, the depicted network functions may be replaced with appropriate EPC entities, such as a Mobility Management Entity (“MME”), a Serving Gateway (“SGW”), a PGW, a Home Subscriber Server (“HSS”), and the like. For example, the AMF 133 may be mapped to an MME, the SMF 135 may be mapped to a control plane portion of a PGW and/ or to an MME, the UPF 131 may be mapped to an SGW and a user plane portion of the PGW, the UDM/UDR 139 may be mapped to an HSS, etc.

[0048] While Figure 1 depicts components of a 5G RAN and a 5G core network, the described embodiments apply to other types of communication networks and RATs, including IEEE 802.11 variants, Global System for Mobile Communications (“GSM”, i.e., a 2G digital cellular network), General Packet Radio Service (“GPRS”), UMTS, LTE variants, CDMA 2000, Bluetooth, ZigBee, Sigfox, and the like.

[0049] In the following descriptions, the term “gNB” is used for the base station but it is replaceable by any other radio access node, e.g., RAN node, eNB, Base Station (“BS”), Access Point (“AP”), NR, etc. Further the operations are described mainly in the context of 5G NR. However, the proposed solutions /methods are also equally applicable to other mobile communication systems supporting CSI enhancements for higher frequencies.

[0050] Figure 2 depicts a user equipment apparatus 200 that may be used for implementing the methods described herein. The user equipment apparatus 200 is used to implement one or more of the solutions described herein. The user equipment apparatus 200 is in accordance with one or more of the user equipment apparatuses described in embodiments herein. In particular, the user equipment apparatus 200 may comprise a remote unit 105 or a UE 410, 510, 610, 810, 910, 1010, 1110, 1210, 1310, 1410 as described herein. The user equipment apparatus 200 includes a processor 205, a memory 210, an input device 215, an output device 220, and a transceiver 225.

[0051] The input device 215 and the output device 220 may be combined into a single device, such as a touchscreen. In some implementations, the user equipment apparatus 200 does not include any input device 215 and/ or output device 220. The user equipment apparatus 200 may include one or more of: the processor 205, the memory 210, and the transceiver 225, and may not include the input device 215 and/or the output device 220.

[0052] As depicted, the transceiver 225 includes at least one transmitter 230 and at least one receiver 235. The transceiver 225 may communicate with one or more cells (or wireless coverage areas) supported by one or more base units. The transceiver 225 may be operable on unlicensed spectrum. Moreover, the transceiver 225 may include multiple UE panels supporting one or more beams. Additionally, the transceiver 225 may support at least one network interface 240 and/ or application interface 245. The application interface (s) 245 may support one or more APIs. The network interface (s) 240 may support 3GPP reference points, such as Uu, Nl, PC5, etc. Other network interfaces 240 may be supported, as understood by one of ordinary skill in the art.

[0053] The processor 205 may include any known controller capable of executing computer-readable instructions and/ or capable of performing logical operations. For example, the processor 205 may be a microcontroller, a microprocessor, a central processing unit (“CPU”), a graphics processing unit (“GPU”), an auxiliary processing unit, a field programmable gate array (“FPGA”), or similar programmable controller. The processor 205 may execute instructions stored in the memory 210 to perform the methods and routines described herein. The processor 205 is communicatively coupled to the memory 210, the input device 215, the output device 220, and the transceiver 225. [0054] The processor 205 may control the user equipment apparatus 200 to implement the user equipment apparatus behaviors described herein. The processor 205 may include an application processor (also known as “main processor”) which manages application-domain and operating system (“OS”) functions and a baseband processor (also known as “baseband radio processor”) which manages radio functions.

[0055] The memory 210 may be a computer readable storage medium. The memory 210 may include volatile computer storage media. For example, the memory 210 may include a RAM, including dynamic RAM (“DRAM”), synchronous dynamic RAM (“SDRAM”), and/or static RAM (“SRAM”). The memory 210 may include non-volatile computer storage media. For example, the memory 210 may include a hard disk drive, a flash memory, or any other suitable non-volatile computer storage device. The memory 210 may include both volatile and non-volatile computer storage media.

[0056] The memory 210 may store data related to implement a traffic category field as described herein. The memory 210 may also store program code and related data, such as an operating system or other controller algorithms operating on the apparatus 200. [0057] The input device 215 may include any known computer input device including a touch panel, a button, a keyboard, a stylus, a microphone, or the like. The input device 215 may be integrated with the output device 220, for example, as a touchscreen or similar touch-sensitive display. The input device 215 may include a touchscreen such that text may be input using a virtual keyboard displayed on the touchscreen and/ or by handwriting on the touchscreen. The input device 215 may include two or more different devices, such as a keyboard and a touch panel.

[0058] The output device 220 may be designed to output visual, audible, and/ or haptic signals. The output device 220 may include an electronically controllable display or display device capable of outputting visual data to a user. For example, the output device 220 may include, but is not limited to, a Liquid Crystal Display (“LCD”), a Light- Emitting Diode (“LED”) display, an Organic LED (“OLED”) display, a projector, or similar display device capable of outputting images, text, or the like to a user. As another, non-limiting, example, the output device 220 may include a wearable display separate from, but communicatively coupled to, the rest of the user equipment apparatus 200, such as a smartwatch, smart glasses, a heads-up display, or the like. Further, the output device 220 may be a component of a smart phone, a personal digital assistant, a television, a table computer, a notebook (laptop) computer, a personal computer, a vehicle dashboard, or the like.

[0059] The output device 220 may include one or more speakers for producing sound. For example, the output device 220 may produce an audible alert or notification (e.g., a beep or chime). The output device 220 may include one or more haptic devices for producing vibrations, motion, or other haptic feedback. All, or portions, of the output device 220 may be integrated with the input device 215. For example, the input device 215 and output device 220 may form a touchscreen or similar touch-sensitive display. The output device 220 may be located near the input device 215.

[0060] The transceiver 225 communicates with one or more network functions of a mobile communication network via one or more access networks. The transceiver 225 operates under the control of the processor 205 to transmit messages, data, and other signals and also to receive messages, data, and other signals. For example, the processor 205 may selectively activate the transceiver 225 (or portions thereof) at particular times in order to send and receive messages.

[0061] The transceiver 225 includes at least one transmitter 230 and at least one receiver 235. The one or more transmitters 230 may be used to provide uplink communication signals to a base unit of a wireless communication network. Similarly, the one or more receivers 235 may be used to receive downlink communication signals from the base unit. Although only one transmitter 230 and one receiver 235 are illustrated, the user equipment apparatus 200 may have any suitable number of transmitters 230 and receivers 235. Further, the transmitter(s) 230 and the receiver(s) 235 may be any suitable type of transmitters and receivers. The transceiver 225 may include a first transmitter/receiver pair used to communicate with a mobile communication network over licensed radio spectrum and a second transmitter/ receiver pair used to communicate with a mobile communication network over unlicensed radio spectrum. [0062] The first transmitter/ receiver pair may be used to communicate with a mobile communication network over licensed radio spectrum and the second transmitter/ receiver pair used to communicate with a mobile communication network over unlicensed radio spectrum may be combined into a single transceiver unit, for example a single chip performing functions for use with both licensed and unlicensed radio spectrum. The first transmitter/receiver pair and the second transmitter/receiver pair may share one or more hardware components. For example, certain transceivers 225, transmitters 230, and receivers 235 may be implemented as physically separate components that access a shared hardware resource and/or software resource, such as for example, the network interface 240.

[0063] One or more transmitters 230 and/ or one or more receivers 235 may be implemented and/ or integrated into a single hardware component, such as a multitransceiver chip, a system-on-a-chip, an Application-Specific Integrated Circuit (“ASIC”), or other type of hardware component. One or more transmitters 230 and/ or one or more receivers 235 may be implemented and/ or integrated into a multi-chip module. Other components such as the network interface 240 or other hardware components/ circuits may be integrated with any number of transmitters 230 and/ or receivers 235 into a single chip. The transmitters 230 and receivers 235 may be logically configured as a transceiver 225 that uses one more common control signals or as modular transmitters 230 and receivers 235 implemented in the same hardware chip or in a multi-chip module.

[0064] Figure 3 depicts further details of the network node 300 that may be used for implementing the methods described herein. The network node 300 may be one implementation of an entity in the wireless communication network, e.g. in one or more of the wireless communication networks described herein. The network node 300 may comprise a base unit 121, a satellite 129, an LMF 420, 520, 620, 1220, 1320 or an AMF 540, 640, 740, 1240, 1340 as described herein. The network node 300 includes a processor 305, a memory 310, an input device 315, an output device 320, and a transceiver 325.

[0065] The input device 315 and the output device 320 may be combined into a single device, such as a touchscreen. In some implementations, the network node 300 does not include any input device 315 and/ or output device 320. The network node 300 may include one or more of: the processor 305, the memory 310, and the transceiver 325, and may not include the input device 315 and/ or the output device 320. [0066] As depicted, the transceiver 325 includes at least one transmitter 330 and at least one receiver 335. Here, the transceiver 325 communicates with one or more remote units 200. Additionally, the transceiver 325 may support at least one network interface 340 and/or application interface 345. The application interface(s) 345 may support one or more APIs. The network interface(s) 340 may support 3GPP reference points, such as Uu, Nl, N2 and N3. Other network interfaces 340 may be supported, as understood by one of ordinary skill in the art.

[0067] The processor 305 may include any known controller capable of executing computer-readable instructions and/ or capable of performing logical operations. For example, the processor 305 may be a microcontroller, a microprocessor, a CPU, a GPU, an auxiliary processing unit, a FPGA, or similar programmable controller. The processor 305 may execute instructions stored in the memory 310 to perform the methods and routines described herein. The processor 305 is communicatively coupled to the memory 310, the input device 315, the output device 320, and the transceiver 325.

[0068] The memory 310 may be a computer readable storage medium. The memory 310 may include volatile computer storage media. For example, the memory 310 may include a RAM, including dynamic RAM (“DRAM”), synchronous dynamic RAM (“SDRAM”), and/or static RAM (“SRAM”). The memory 310 may include non-volatile computer storage media. For example, the memory 310 may include a hard disk drive, a flash memory, or any other suitable non-volatile computer storage device. The memory 310 may include both volatile and non-volatile computer storage media.

[0069] The memory 310 may store data related to establishing a multipath unicast link and/ or mobile operation. For example, the memory 310 may store parameters, configurations, resource assignments, policies, and the like, as described herein. The memory 310 may also store program code and related data, such as an operating system or other controller algorithms operating on the network node 300.

[0070] The input device 315 may include any known computer input device including a touch panel, a button, a keyboard, a stylus, a microphone, or the like. The input device 315 may be integrated with the output device 320, for example, as a touchscreen or similar touch-sensitive display. The input device 315 may include a touchscreen such that text may be input using a virtual keyboard displayed on the touchscreen and/ or by handwriting on the touchscreen. The input device 315 may include two or more different devices, such as a keyboard and a touch panel. [0071] The output device 320 may be designed to output visual, audible, and/ or haptic signals. The output device 320 may include an electronically controllable display or display device capable of outputting visual data to a user. For example, the output device 320 may include, but is not limited to, an LCD display, an LED display, an OLED display, a projector, or similar display device capable of outputting images, text, or the like to a user. As another, non-limiting, example, the output device 320 may include a wearable display separate from, but communicatively coupled to, the rest of the network node 300, such as a smartwatch, smart glasses, a heads-up display, or the like. Further, the output device 320 may be a component of a smart phone, a personal digital assistant, a television, a table computer, a notebook (laptop) computer, a personal computer, a vehicle dashboard, or the like.

[0072] The output device 320 may include one or more speakers for producing sound. For example, the output device 320 may produce an audible alert or notification (e.g., a beep or chime). The output device 320 may include one or more haptic devices for producing vibrations, motion, or other haptic feedback. All, or portions, of the output device 320 may be integrated with the input device 315. For example, the input device 315 and output device 320 may form a touchscreen or similar touch-sensitive display. The output device 320 may be located near the input device 315.

[0073] The transceiver 325 includes at least one transmitter 330 and at least one receiver 335. The one or more transmitters 330 may be used to communicate with the UE, as described herein. Similarly, the one or more receivers 335 may be used to communicate with network functions in the PLMN and/ or RAN, as described herein. Although only one transmitter 330 and one receiver 335 are illustrated, the network node 300 may have any suitable number of transmitters 330 and receivers 335. Further, the transmitter(s) 330 and the receiver(s) 335 may be any suitable type of transmitters and receivers.

[0074] 3GPP TR 38.882 vl8.0.0 identified a need to define a network-based solution which aims at verifying reported UE location information. In Rel-18, the Network Induced Location Reporting (NLLR) procedure was adopted in Non-Terrestrial Networks (NTN) to verify reported UE location information. Positioning techniques in 3GPP are developed by considering the typical scenarios in terrestrial networks, where measurements from at least three terrestrial gNBs are usually used for location estimates. The method of generating such location estimates is sometimes referred to as triangulating. However, such scenarios may be hard to find in NTNs as one of the common scenarios in NTN is that the UEs are usually in the coverage area of only a single node, in the form of an aircraft or a satellite. Therefore, existing positioning methods must be adapted for use in cases where the UE is located in the coverage area of a single satellite. One method for triangulating from a single node comprises a timebased method that utilizes the movement of Non-Geostationary (NGSO) satellites, by performing range measurements at multiple time instances from the same satellite. However, such methodology may result in some limitations and low accurate location estimates.

[0075] For instance, if the UEs are located along and/ or near the ground track or the orbital plane of only a single satellite coverage area (i.e., an NGSO satellite) and are connected to NG-RAN through that single satellite, the positioning accuracy would always be lower than the predefined accuracy threshold for verification, i.e., 5—10 km. Therefore, the UEs located near the orbital plane may not be able to verify their location due to radio and satellite geometrical limitations of the positioning methods. In such a case, these UEs may always be deregistered from network. However, such deregistering would not be because the UEs are necessarily invalid, but because they do not fulfill the accuracy threshold for location verification due to the technical NTN limitations of timebased positioning methods. The present disclosure provides a set of procedural enhancements to address the verification procedure for those UEs that are located near the ground track of a non-terrestrial network node.

[0076] The ground track is a path on the surface of the Earth directly below an aircraft or satellite trajectory. In the case of satellites, it is also known as a suborbital track, and is the vertical projection of the satellite’s orbit onto the surface of the Earth. The ground track may be referred to as the ground trace. Where the non-terrestrial network node is a satellite, the ground track may be defined as the line of intersection between an orbital plane of the satellite and the surface of the Earth.

[0077] Positioning requirements in terrestrial wireless communication networks were defined in previous 3GPP standard releases: Rel-16 & Rel-17. Positioning Requirements NR positioning based on NR Uu signals and SA architecture (e.g. beam-based transmissions) was first specified in Rel-16. The target use cases also included commercial and regulatory (emergency services) scenarios as in Rel-15. The performance requirements defined in 3GPP TR 38.855 vl6.0.0 (28 March 2019) are shown in table 1 on next page.

Table 1: Performance requirements from 3GPP TR 38.855 vl6.0.0

[0078] Current 3GPP Rel-17 Positioning has recently defined the positioning performance requirements for Commercial and IIoT use cases, as defined in 3GPP TR 38.857 vl 7.0.0 (30 March 2021), shown in table 2 below.

Table 2: Performance requirements from 3GPP TR 38.855 vl6.0.0

[0079] Table 3 shows the supported positioning techniques in Rel-16, as defined in 3GPP TS 38.305 vl7.3.0 (13 January 2023). Separate positioning techniques as indicated in Table 3 can be currently configured and performed based on the requirements of the LMF and UE capabilities. The transmission of Positioning Reference Signals (PRS) enables the UE to perform UE positioning-related measurements to enable the computation of a UE’s location estimate and are configured per Transmission Reception Point (TRP), where a TRP may transmit one or more beams.

[0080] Table 3 follows on the next page. able 3: Supported Rel-16 UE positioning methods defined by TS 38.305 vl7.3.0

[0081] The following few paragraphs describe some RAT-dependent positioning techniques supported in Rel-16, as defined in 3GPP TS 38.305 vl7.3.0.

[0082] DL-TDoA (Downlink Time Difference Of Arrival) - The DL-TDOA positioning method makes use of the DL RSTD (and optionally DL Positioning Reference Signals (PRS) Reference Signal Received Power (RSRP)) of downlink signals received from multiple TPs, at the UE. The UE measures the DL Reference Signal Time Difference (RSTD) (and optionally DL PRS RSRP) of the received signals using assistance data received from the positioning server, and the resulting measurements are used along with other configuration information to locate the UE in relation to the neighboring Transmission Points (TPs).

[0083] DL-AoD (Downlink Angle-of-Departure) - The DL AoD positioning method makes use of the measured DL PRS RSRP of downlink signals received from multiple TPs, at the UE. The UE measures the DL PRS RSRP of the received signals using assistance data received from the positioning server, and the resulting measurements are used along with other configuration information to locate the UE in relation to the neighboring TPs.

[0084] Multi-RTT (Multiple-Round Trip Time) - The Multi-RTT positioning method makes use of the UE Rx-Tx measurements and DL PRS RSRP of downlink signals received from multiple Transmission-Reception Points (TRPs), measured by the UE and the measured gNB Rx-Tx measurements and UL SRS-RSRP at multiple TRPs of uplink signals transmitted from UE.

[0085] The UE measures the UE Rx-Tx measurements (and optionally DL PRS RSRP of the received signals) using assistance data received from the positioning server, and the TRPs measure the gNB Rx-Tx measurements (and optionally UL SRS-RSRP of the received signals) using assistance data received from the positioning server. The measurements are used to determine the RTT at the positioning server which are used to estimate the location of the UE.

[0086] E-CID/ NR E-CID (Enhanced Cell ID) - According to E-CID positioning methods, the position of a UE is estimated with the knowledge of its serving NG-eNB, gNB and cell and is based on LTE signals. The information about the serving NG-eNB, gNB and cell may be obtained by paging, registration, or other methods. NR Enhanced Cell ID (NR E-CID) positioning refers to techniques which use additional UE measurements and/ or NR radio resource and other measurements to improve the UE location estimate using NR signals.

[0087] Although NR E-CID positioning may utilize some of the same measurements as the measurement control system in the RRC protocol, the UE generally is not expected to make additional measurements for the sole purpose of positioning; i.e., the positioning procedures do not supply a measurement configuration or measurement control message, and the UE reports the measurements that it has available rather than being required to take additional measurement actions.

[0088] UL-TDoA (Uplink Time Difference Of Arrival) - The UL TDOA positioning method makes use of the UL TDOA (and optionally UL SRS-RSRP) at multiple RPs of uplink signals transmitted from UE. The RPs measure the UL TDOA (and optionally UL SRS-RSRP) of the received signals using assistance data received from the positioning server, and the resulting measurements are used along with other configuration information to estimate the location of the UE.

[0089] UL-AoA (Uplink Angle-of-Arrival) - The UL AoA positioning method makes use of the measured azimuth and the zenith of arrival at multiple RPs of uplink signals transmitted from UE. The RPs measure A- AoA and Z-AoA of the received signals using assistance data received from the positioning server, and the resulting measurements are used along with other configuration information to estimate the location of the UE.

[0090] The following paragraphs describes some RAT-Independent Positioning Techniques supported in Rel-16 and as defined in 3GPP TS 38.305 v!7.3.0. [0091] Network-assisted Global Navigation Satellite System (GNSS) methods make use of UEs that are equipped with radio receivers capable of receiving GNSS signals. In 3GPP specifications the term GNSS encompasses both global and regional/ augmentation navigation satellite systems. Examples of global navigation satellite systems include GPS, Modernized GPS, Galileo, GLONASS, and BeiDou Navigation Satellite System (BDS). Regional navigation satellite systems include Quasi Zenith Satellite System (QZSS) while the many augmentation systems, are classified under the generic term of Space Based Augmentation Systems (SB AS) and provide regional augmentation services. In this concept, different GNSSs (e.g. GPS, Galileo, etc.) can be used separately or in combination to determine the location of a UE.

[0092] Barometric pressure sensor positioning - The barometric pressure sensor method makes use of barometric sensors to determine the vertical component of the position of the UE. The UE measures barometric pressure, optionally aided by assistance data, to calculate the vertical component of its location or to send measurements to the positioning server for position calculation. This method should be combined with other positioning methods to determine the 3D position of the UE.

[0093] WLAN positioning - The WLAN positioning method makes use of the WLAN measurements (AP identifiers and optionally other measurements) and databases to determine the location of the UE. The UE measures received signals from WLAN access points, optionally aided by assistance data, to send measurements to the positioning server for position calculation. Using the measurement results and a references database, the location of the UE is calculated. Alternatively, the UE makes use of WLAN measurements and optionally WLAN AP assistance data provided by the positioning server, to determine its location.

[0094] Bluetooth positioning - The Bluetooth positioning method makes use of Bluetooth measurements (beacon identifiers and optionally other measurements) to determine the location of the UE. The UE measures received signals from Bluetooth beacons. Using the measurement results and a references database, the location of the UE is calculated. The Bluetooth methods may be combined with other positioning methods (e.g. WLAN) to improve positioning accuracy of the UE.

[0095] TBS positioning - A Terrestrial Beacon System (TBS) consists of a network of ground-based transmitters, broadcasting signals only for positioning purposes. The current type of TBS positioning signals are the MBS (Metropolitan Beacon System) signals and Positioning Reference Signals (PRS) (as defined in 3GPP TS 36.211 vl7.2.0). The UE measures received TBS signals, optionally aided by assistance data, to calculate its location or to send measurements to the positioning server for position calculation. [0096] Motion sensor positioning - The motion sensor method makes use of different sensors such as accelerometers, gyros, magnetometers, to calculate the displacement of UE. The UE estimates a relative displacement based upon a reference position and/ or reference time. UE sends a report comprising the determined relative displacement which can be used to determine the absolute position. This method should be used with other positioning methods for hybrid positioning.

[0097] Figure 4 illustrates an example of positioning measurements and reference signals for determining the location of a wireless communication device in a terrestrial wireless communication network. The wireless communication network comprises a first base station 431, a second base station 432, and a third base station 433. Each base station comprises a plurality of DL-PRS resources. The DL-PRS resources for each base station 431, 432, 433 are illustrated as comprising two sets: Resource Set ID #0 and Resource Set ID #1. The third base station is the serving node for a UE 410. Each base station 431, 432, 433 communicates with a location server 420. The location server 420 may comprise a Location Management Function (LMF). A base station may communicate with the location server 420 using the NRPPa interface.

[0098] According to Rel-16, the PRS can be transmitted by different base stations (serving and neighboring) using narrow beams over FR1 and FR2 as illustrated in Figure 4, which is relatively different when compared to LTE where the PRS was transmitted across the whole cell. The PRS can be locally associated with a PRS Resource ID and Resource Set ID for a base station (TRP). Similarly, UE positioning measurements such as Reference Signal Time Difference (RSTD) and PRS RSRP measurements are made between beams (e.g., between a different pair of DL PRS resources or DL PRS resource sets) as opposed to different cells as was the case in LTE. In addition, there are additional UL positioning methods for the network to exploit in order to compute the target UE’s location. Table 4 and Table 5 on the following page show the reference signal to measurements mapping required for each of the supported RAT-dependent positioning techniques at the UE and gNB, respectively. RAT-dependent positioning techniques involve the 3GPP RAT and core network entities to perform the position estimation of the UE, which are differentiated from RAT-independent positioning techniques which rely on GNSS, IMU sensor, WLAN and Bluetooth technologies for performing target device (UE) positioning.

Table 4: UE Measurements to enable RAT-dependent positioning techniques

Table 5: gNB Measurements to enable RAT-dependent positioning techniques

[0099] According to 3GPP TS 38.215 vl7.2.0, UE measurements have been defined, which are applicable to DL-based positioning techniques, see subclause 2.4 thereof. For a conceptual overview of the current implementation in Rel-16, the assistance data configurations (see Table 6) and measurement information (see Table 7) are provided below for each of the supported positioning techniques.

Table 6: DL-TDO A Assistance Data according to 3GPP TS 37.355 v 17.3.0

Table 7: DL-TDOA Measurement Report according to 3GPP TS 37.355 v 17.3.0

[0100] Examples of RAT-dependent Positioning Measurements are defined in table 8 below. The different DL measurements including DL PRS-RSRP, DL RSTD and UE Rx-Tx Time Difference required for the supported RAT-dependent positioning techniques are mentioned. The following measurement configurations are specified in 3GPP TS 38.215 vl7.2.0: 4 Pair of DL RSTD measurements can be performed per pair of cells. Each measurement is performed between a different pair of DL PRS Resources/Resource Sets with a single reference timing. 8 DL PRS RSRP measurements can be performed on different DL PRS resources from the same cell.

Table 8: DL Measurements required for DL-based positioning methods

[0101] Figure 5 shows the architecture 500 in 5GS applicable to positioning of a UE with NR or E-UTRA access. The architecture 500 comprises a UE 510 communicating with an NG-RAN 530, the NG-RAN 530 comprising a gNB 534 and an ng-eNB 535. The network further comprises an LMF 520 and an AMF 540.

[0102] The AMF 540 receives a request for some location service associated with a particular target UE 510 from another entity (e.g., GMLC or UE) or the AMF 540 itself decides to initiate some location service on behalf of a particular target UE 510 (e.g., for an IMS emergency call from the UE 510) as described in [3GPP TS 23.502 vl8.0.0] and [3GPP TS 23.273 vl8.0.0]. The AMF 540 then sends a location services request to the LMF 520. The LMF 520 processes the location services request which may include transferring assistance data to the target UE 510 to assist with UE-based and/or UE- assisted positioning and/ or may include positioning of the target UE. The LMF 520 then returns the result of the location service back to the AMF 540 (e.g., a position estimate for the UE. In the case of a location service requested by an entity other than the AMF 540 (e.g., a GMLC or UE), the AMF 540 returns the location service result to this entity.

[0103] An NG-RAN node 530 may control several TRPs/TPs, such as remote radio heads, or DL-PRS-only TPs for support of PRS-based TBS.

[0104] In general, an LMF may have a proprietary signalling connection to an E-SMLC which may enable an LMF to access information from E-UTRAN (e.g. to support the OTDOA for E-UTRA positioning method using downlink measurements obtained by a target UE of signals from eNBs and/ or PRS-only TPs in E-UTRAN). Details of the signalling interaction between an LMF and E-SMLC are outside the scope of this specification.

[0105] An LMF may have a proprietary signalling connection to an SLP. The SLP is the SUPL entity responsible for positioning over the user plane. Further details of user-plane positioning are provided in 3GPP TS 38.305 vl 7.3.0 Annex A. Details of the signalling interaction between an LMF and SLP are outside the scope of this specification.

[0106] In case of split gNB architecture, a gNB-DU may include TRP functionality where the TRP functionality may support functions for a TP, RP or both TP and RP. A gNB-DU which includes TRP functionality does not need to offer cell services. [0107] Figure 6 illustrates Location Service Support by NG-RAN which may include RAN-UE Positioning Operations. To support positioning of a target UE and delivery of location assistance data to a UE with NG-RAN access in 5GS, location related functions are distributed as shown in the architecture 500 in Figure 5 and as clarified in greater detail in [3GPP TS 23.501 vl8.0.0] and [3GPP TS 23.273 vl8.0.0]. The overall sequence of events 600 applicable to the UE, NG-RAN and LMF for any location service is shown in Figure 6.

[0108] The method 600 illustrated by figure 6 takes place between a UE 610 an NG- RAN node 630. an AMF 640, an LMF 620 and a 5GC LCS Entity 645.

[0109] Note that when the AMF receives a Location Service Request in case of the UE is in CM-IDLE state, the AMF performs a network triggered service request as defined in [3GPP TS 23.502 vl8.0.0] and [3GPP TS 23.273 vl8.0.0] in order to establish a signalling connection with the UE and assign a specific serving gNB or ng-eNB. The UE is assumed to be in connected mode before the beginning of the flow shown in the Figure 6; that is, any signalling that might be required to bring the UE to connected mode prior to step 671a is not shown. The signalling connection may, however, be later released (e.g. by the NG-RAN node as a result of signalling and data inactivity) while positioning is still ongoing.

[0110] At 671a, either some entity in the 5GC (e.g. GMLC) requests some location service (e.g. positioning) for a target UE to the serving AMF; or at 671b, the serving AMF for a target UE determines the need for some location service (e.g. to locate the UE for an emergency call); at 671c, the UE requests some location service (e.g. positioning or delivery of assistance data) to the serving AMF at the NAS level.

[0111] At 672, the AMF transfers the location service request to an LMF.

[0112] At 673a, the LMF instigates location procedures with the serving and possibly neighboring ng-eNB or gNB in the NG-RAN — e.g. to obtain positioning measurements or assistance data.

[0113] At 673b, in addition to step 673a or instead of step 673a, the LMF instigates location procedures with the UE — e.g. to obtain a location estimate or positioning measurements or to transfer location assistance data to the UE.

[0114] At 674, the LMF provides a location service response to the AMF and includes any needed results — e.g. success or failure indication and, if requested and obtained, a location estimate for the UE. [0115] At 675a, if step 671a was performed, the AMF returns a location service response to the 5GC entity in step 671a and includes any needed results — e.g. a location estimate for the UE.

[0116] At 675b, if step 671b occurred, the AMF uses the location service response received in step 674 to assist the service that triggered this in step 671b (e.g. may provide a location estimate associated with an emergency call to a GMLC).

[0117] At 675c, if step 671c was performed, the AMF returns a location service response to the UE and includes any needed results — e.g. a location estimate for the UE.

[0118] Location procedures applicable to NG-RAN occur in steps 673a and 673b in Figure 6 and are defined in greater detail in this specification. Other steps in Figure 6 are applicable only to the 5GC and are described in greater detail and in 3GPP TS 23.502 V18.0.0 and 3GPP TS 23.273 vl8.0.0.

[0119] Steps 673a and 673b can involve the use of different position methods to obtain location related measurements for a target UE and from these computes a location estimate and possibly additional information like velocity.

[0120] Figure 7 illustrates an NG-RAN Location Reporting Procedure 700. The procedure 700 takes place between an NG-RAN 730 and an AMF 740. This procedure is used by an AMF to request the NG-RAN to report where the UE is currently located when the target UE is in CM-CONNECTED state. The need for the NG-RAN to continue reporting ceases when the UE transitions to CM-IDLE or the AMF sends cancel indication to NG-RAN. This procedure may be used for services that require accurate cell identification (e.g. emergency services, lawful intercept, charging), or for subscription to the service by other NFs. When Dual Connectivity is activated, PSCell information is only reported if requested by the AMF.

[0121] At 771, the AMF 740 sends to the NG-RAN 730: Location Reporting Control (Reporting Type, Location Reporting Level, (Area Of Interest, Request Reference ID)). [0122] The AMF 740 sends a Location Reporting Control message to the NG-RAN 730. The Location Reporting Control message shall identify the UE for which reports are requested and shall include Reporting Type and Location Reporting Level. The Location Reporting Control message may also include Area Of Interest and Request Reference ID. Location Reporting Level could be TAI+ Cell Identity. Reporting Type indicates whether the message is intended to trigger a single standalone report about the current Cell Identity serving the UE or start the NG-RAN to report whenever the UE changes cell, or ask the NG-RAN to report whenever the UE moves out or into the Area Of Interest. If the Reporting Type indicates to report whenever the UE changes cell and if PScell reporting is requested and Dual Connectivity is in use, the Master RAN node shall also report to the AMF whenever the PSCell changes. If the Reporting Type indicates to start the NG-RAN to report when UE moves out of or into the Area Of Interest, the AMF also provides the requested Area Of Interest information in the Location Reporting Control message. The AMF may include a Request Reference ID in the Location Report Control message to identify the request of reporting for an Area Of Interest. If multiple Areas Of Interest are included in the message, the Request Reference ID identifies each Area of Interest.

[0123] NOTE 1: Requesting reports whenever the UE changes cell can increase signalling load on multiple interfaces. Requesting reports for all changes in PSCell ID can further increase signalling load. Hence it is recommended that any such reporting is only applied for a limited number of subscribers.

[0124] At 772, the NG-RAN 730 sends to the AMF 740: Location Report (UE Location, UE Presence in Area Of Interest, Request Reference ID, Timestamp).

[0125] The NG-RAN 740 sends a Location Report message informing the AMF 740 about the location of the UE which shall be represented as the requested Location Reporting Level. If PSCell reporting is requested and Dual Connectivity is activated, then the Master NG-RAN node shall also include the PSCell ID. With NR satellite access, cell and TAI reporting by NG-RAN refer to a fixed cell and fixed TA in which a UE is geographically located. As part of the User Location Information, NG_RAN also reports one or more TACs for the Selected PLMN as described in TS 38.413 [10], but it is not guaranteed that the UE is always located in one of these TACs.

[0126] When UE is in CM-CONNECTED with RRC Inactive state, if NG-RAN has received Location Reporting Control message from AMF with the Reporting Type indicating single stand-alone report, the NG-RAN shall perform NG-RAN paging before reporting the location to the AMF. The NG-RAN should send the Location Report promptly and shall not wait to attempt to create a Dual Connectivity configuration. However, if PSCell reporting is requested and the PSCell ID is known to the Master RAN node, then it shall be included in the Location Report. In the case of RAN paging failure, the RAN reports UE's last known location with time stamp.

[0127] When UE is in CM-CONNECTED with RRC Inactive state, if NG-RAN has received Location Reporting Control message from AMF with the Reporting Type indicating continuous reporting whenever the UE changes cell, the NG-RAN shall send a Location Report message to the AMF including the UE's last known location with time stamp. If the UE was using Dual Connectivity immediately before entering CM- CONNECTED with RRC Inactive state and PSCell reporting is requested, then the Location Report shall also include the PSCell ID.

[0128] When UE is in CM-CONNECTED, if NG-RAN has received Location Reporting Control message from AMF with the Reporting Type of Area Of Interest based reporting, the NG-RAN shall track the UE presence in Area Of Interest and send a Location Report message to AMF including the UE Presence in the Area Of Interest (i.e. IN, OUT, or UNKNOWN) as described in clause D.2 and the UE's current location (including the PSCell ID if PSCell reporting is requested and Dual Connectivity is activated) when the UE is in RRC Connected state, or, when the UE is in RRC Inactive state, the UE's last known location (including the PSCell ID if PSCell reporting is requested and the UE was using Dual Connectivity immediately before entering CM- CONNECTED with RRC Inactive state) with time stamp if the NG-RAN perceives that the UE presence in the Area Of Interest is different from the last one reported. When the NG-RAN detects that the UE has moved out of or into multiple areas of interest, it sends multiple pairs of UE Presence in the Area Of Interest and the Request Reference ID in one Location Report message to AMF. If UE transitions from RRC Inactive state to RRC Connected state, NG-RAN shall check the latest location (including the PSCell ID if PSCell reporting is requested and Dual Connectivity is activated) of UE and follow the rules when UE is in RRC Connected.

[0129] The AMF may receive Location Report even if the UE presence in Area Of Interest is not changed. The AMF stores the latest received PSCell ID with its associated timestamp. The AMF stores the latest received PSCell ID with its associated timestamp, when available.

[0130] At 773, the AMF 740 sends to the NG-RAN 530: Cancel Location Report (Reporting Type, Request Reference ID).

[0131] The AMF 740 can send a Cancel Location Reporting message to inform the NG- RAN 730 that it should terminate the location reporting for a given UE corresponding to the Reporting Type or the location reporting for Area Of Interest indicated by Request Reference ID. This message is needed when the reporting type was requested for continuously reporting or for the Area Of Interest. The AMF may include the Request Reference ID which indicates the requested Location Reporting Control for the Area Of Interest, so that the NG-RAN should terminate the location reporting for the Area Of Interest.

[0132] Note also that Location reporting related information of the source NG-RAN node is transferred to the target NG-RAN node during Xn handover. According to 3GPP release 16, the location reporting procedure is applicable only to 3GPP access. NTN NG-RAN Architecture is defined in 3GPP TR 38.821 vl6.1.0.

[0133] Figure 8 illustrates a transparent satellite-based NG-RAN architecture 800. A UE 810 connects to a gNB 831 via a remote radio unit 835. The remote radio unit 835 comprises a satellite 838 and an NTN gateway 839. The gNB 831 connects to a 5G core network (CN) 825, which in turn connects to a data network 850. This architecture 800 allows the UE 810 to communicate with the data network 850. The satellite payload implements frequency conversion and a Radio Frequency amplifier in both up link and down link direction. It corresponds to an analogue RF repeater. Hence the satellite repeats the NR-Uu radio interface from the feeder link (between the NTN gateway and the satellite) to the service link (between the satellite and the UE) and vice versa.

[0134] The Satellite Radio Interface (SRI) on the feeder link is the NR-Uu. In other words, the satellite does not terminate NR-Uu. The NTN GW supports all necessary functions to forward the signal of NR-Uu interface. Different transparent satellites may be connected to the same gNB on the ground. Note that whilst several gNBs may access a single satellite payload, the description has been simplified to a unique gNB accessing the satellite payload, without loss of generality.

[0135] Figure 9 illustrates an architecture 900 comprising a regenerative satellite without Inter-Satellite Links (ISL) and with a gNB processed payload. A UE 910 connects by radio link to a satellite based gNB 934, which in turn is connected to a ground-based NTN Gateway 939 by a Satellite Radio Interface (SRI). The NTN Gateway 939 connects to a 5G CN 935, which in turn connects to a data network 950. This architecture 900 allows the UE 910 to communicate with the data network 950.

[0136] The NG-RAN logical architecture as described in 3GPP TS 38.401 vl7.3.0 may be used as baseline for NTN scenarios. The satellite payload implements regeneration of the signals received from Earth. An NR-Uu radio interface is used on the service link between the UE 910 and the satellite 934. A Satellite Radio Interface (SRI) is used on the feeder link between the NTN gateway 939 and the satellite 934. The SRI (Satellite Radio Interface) is a transport link between NTN GW 939 and satellite 934. [0137] Note that the satellite may embark additional traffic routing functions that are out of RAN scope. The satellite payload also provides Inter- Satellite Links (ISL) between satellites. An ISL (Inter- Satellite Link) is a transport link between satellites. An ISL may be a radio interface or an optical interface that may be 3GPP or non 3GPP defined. The NTN GW 939 is a Transport Network Layer node and supports all necessary transport protocols.

[0138] Figure 10 illustrates an architecture 1000 comprising a regenerative satellite with ISL and a gNB processed payload. An NG-RAN 1030 comprises a plurality of satellite gNBs 1033, 1034 each connected to a respective NTN Gateway 1039a, 1039b.

[0139] Figure 10 shows a UE 1010 that is connected to a satellite gNB 1033, which is in turn connected to a respective NTN gateway 1039a. NTN gateway 1039a connects to a data network 1050 via a 5G CN 1035. Figure 10 also shows a second UE 1011 that is connected to a satellite gNB 1034, which is in turn connected to a respective NTN gateway 1039b. NTN gateway 1039b connects to a data network 1051 via a 5G CN 1036.

[0140] The architecture 1000 illustrates that a UE served by a gNB on board a satellite could access the 5GCN via ISL. The gNB 1033, 1034 on board different satellites may be connected to the same 5GCN on the ground. If the satellite hosts more than one gNB, the same SRI will transport all the corresponding NG interface instances.

[0141] Figure 11 is an example illustration of technical limitation of position accuracy for time-based methods with a single satellite node. Figure 11 shows the surface of the Earth 1100 with a ground track 1101 of a satellite orbit projected thereon. Three RTT measurements are taken at times tl, t2 and t3, the location of the satellite is shown on the ground track at each of these three times. Each RTT measurement gives an annular area defining the possible locations of the UE that would satisfy the RTT measurement.

Each annular area has a thickness defined by the RTT measurement error. The annular areas for three measurements ml, m2 and m3 are shown, these measurements taken at times tl, t2 and t3 respectively.

[0142] For time-based positioning methods such as multi-RTT and DL/UL-TDOA with a single satellite, typically three measurements are taken at different time instances to estimate the UE location. However, the circle/rings formed by the measurements, ml, m2 and m3 at the three-time instances tl, t2 and t3 are centered along the satellite orbital plane. The annular measurement areas may coincide at a point on the ground track 1101 and thus create an elongated region of uncertainty many times longer than the thickness of each annular area defined by the RTT measurement error. Such a large intersectional area is illustrated in Figure 11.

[0143] The UEs that are connected to single satellite and are located along and/ or near the orbital plane of a satellite coverage may not be able to satisfy the accuracy threshold for location verification, resulting in deregistration of these UE, even though these UEs are valid UEs. This is because of the limitation of time-based positioning methods to accurately estimate the target UE location near the satellite orbit, when used for single satellites. For example, as shown in figure 11, the triangulation of three estimates of time measurements, e.g., UE Rx-Tx time difference, RSTD measurements obtained from a single satellite using a time -based method (e.g., multi-RTT or DL-TDOA) would result in a large intersection uncertainty area for UEs that are located near the satellite orbital plane, thus resulting in inaccurate position that may not fulfil the verification criteria. By way of example, the long axis of the intersection area illustrated in figure 11 may be around 5 to 10 km in length.

[0144] The present disclosure provides enhancements for enabling network verified location of the target-UE that are located near the satellite orbital plane such that these UEs may not be deregistered if they are valid UEs. For instance, the verification procedure may be optional for UEs that have technical limitations, where AMF, based on explicit or implicit indications, would need to determine that UEs are located near the satellite orbit. This may require enhancements to NI-LR procedure to verify and determine by AMF that UE is located near the satellite orbital plane.

[0145] There is presented herein a solution to the problem of verification of a UEs position when it is located on the orbital plane of single satellite. According to a first example, the AMF does not deregister a UE that does not fulfil accuracy requirements for verification, if the AMF determines that the UE is located near the orbital plane. The AMF may determined that the UE is near the orbital plane either based on an explicit or an implicit indication. If the UE is determined to be on or near the ground track / orbital plane, then the AMF determines that the accuracy threshold for deregistration is not met because of technical limitations of the positioning method employed. The AMF may additionally employ additional procedures to determine the cause of inaccurate position estimates in case of a UE location determined form measurements taken from a single non-terrestrial network node.

[0146] In one example, the AMF may elect to postpone deregistering such a UE for a certain time period. During that time period the AMF may initiate the NI-LR procedure again for verification. In one implementation, the AMF may indicate to LMF that periodic, or aperiodic, or semi persistent based location estimates may be required for any UE that is located near the orbital plane. In another implementation, the LMF may initiate a repetitive location estimates procedure to determine that a UE is still near the orbital plane or not and report this to AMF as soon as the location estimates of the target UE are changed.

[0147] Figure 12 illustrates NI-LR procedure 1200 to verify the UE location. The procedure 1200 is performed by a UE 1210, an NG-RAN node 1230, an AMF 1240 and an LMF 1220. An indication may be provided in an NI-LR procedure about UEs that are located near the ground track. The AMF 1240 may elect to not deregister UEs based on the implicit or explicit indication in NLLR procedure request response messages that UEs inaccurate location estimates are due to geometrical limitations of the positioning method. For example, the AMF 1240 may determine based on an indication/information in the Nlmf_Location_DetermineLocation response message that the location is not verifiable because of technical NTN geometric limitations of a RAT-dependent timingbased UE positioning method.

[0148] At 1271, a trigger for the AMF 1240 to initiate the 5GC-NI-LR procedure happens when the AMF 1240 decides to verify UE location (country or international area) via LCS service for the UE 1210 as it registers or is registered for NR satellite access.

[0149] The AMF 1240 selects an LMF 1220 based on NRF query or configuration in AMF 1240 and invokes the Nlmf_Location_DetermineLocation service operation towards the LMF 1220 to request the current location of the UE 1210. The service operation may include an LCS Correlation identifier, the serving cell identity of the Primary Cell in the Master RAN node and the Primary Cell in the Secondary RAN node when available based on Dual Connectivity scenarios, and/ or an indication of a location request from a regulatory services client (e.g., emergency services) and may include an indication if UE supports LPP, the required QoS and Supported GAD shapes, the UE Positioning Capability if available. When the AMF 1240 needs to know the country of the UE 1210, an indication of this is also included. The AMF 1240 may include a verification flag to indicate to the LMF 1220 (which may be a location server) that the positioning estimates are for verification purposes based on the NI-LR (network-induced location request). [0150] The AMF 1240 may additionally indicate along with the verification flag about the number of satellites that are providing coverage to the target UE and that these satellites (e.g., TRPs) are connected to one NG-RAN node or multiple NG-RAN nodes (e.g., multiple satellites connected to a single NG-RAN node or multiple satellites connected to multiple NG-RAN nodes). In this case information about a satellite number, satellite location coordinates or ephemeris, type of satellites may be part of request message. The AMF 1240 may additionally include the required accuracy for verification in the request message, for example in QoS LCS accuracy (e.g., 5—10 Km for verification purpose).

[0151] At 1273, upon reception of this message, the IMF 1220 selects one of the methods that can be used for verification purposes, e.g., multi-RTT or DL-TDOA method or any other RAT-dependent method. In one example, when there is no information provided by the AMF 1240 about the number of satellites (e.g., TRP) that are providing coverage to the target UE, the LMF first determines this information from the target UE (e.g., via LPP) and/ or NG-RAN node (e.g., via NRPPa interface). Based on the information about number of satellites (TRPs) in view to the target UE, the LMF selects the appropriate method, e.g., multi-RTT for single satellite, multi-RTT for multisatellites, and DL-TDOA for multiple satellite case. LMF then employs LPP and/ or NRPPa protocols to estimate the target UE position for verification purpose.

[0152] When the LMF 1220 knows the verification accuracy limit that is indicated in the request message by AMF 1240 and determines that the accuracy of positioning method is lower than the threshold accuracy requirements for verification and a single satellite based positioning method is used, the LMF would respond with a failure message. The LMF may initiate additional procedures to determine the cause of inaccurate positioning method (e.g., UE is located near the orbital plane of satellite resulting in case of an inaccurate positioning estimates). In the case when the LMF 1220 does not know the verification accuracy, the LMF may still initiate a procedure to determine whether the target UE is located near the orbital plane or not, in case of single satellite and time based methods for verification purposes.

[0153] At 1274, the LMF 1220 returns the Nlmf_Location_DetermineLocation Response towards the AMF 1240 to return the current location of the UE 1210. The service operation includes the LCS Correlation identifier, the location estimate, its age and accuracy and may include information about the positioning method and the timestamp of the location estimate. The LMF may include information about the number of satellites (e.g., TRPs) that are used for a configured RAT-dependent positioning method. This information may be part of positioning method information (e.g., single satellite multi-RTT or multi-satellite multi-RTT methos are used) or separately indicated with a field. The service operation also includes the UE Positioning Capability if the UE Positioning Capability is received in step 1273 including an indication that the capabilities are non-variable and not received from AMF in step 1272.

[0154] In case the LMF 1220 knows the verification accuracy limit that is indicated in the request message by the AMF 1240 and determines that the accuracy of positioning method is lower than the threshold accuracy requirements for verification, the LMF 1220 would respond with a failure message and may include additional information in the response message to indicate the cause of inaccurate positioning method, e.g., technical limitations of positioning method because of UE location near the orbital plane of the satellite. In case, when LMF does not know the verification accuracy, the LMF my still include information (in case of single satellite and location estimates are for verification purposes) that target UE is located near the satellite orbit plane or not.

[0155] At 1275, upon reception of Nlmf_Location_DetermineLocation response message, the AMF 1240 would verify the location. In case the accuracy of the location estimates do not fulfill the verification threshold or in case of failure message, the AMF 1240 may either deregister the UE 1210 or may not deregister the UE 1210, if the LMF 1240 determines that the accuracy requirements are not fulfilled due to the technical limitations of the positioning method. For example, this may be determined by the AMF 1240 from the LMF response message, if the LMF 1240 indicates in its response message that the cause of inaccurate positioning estimates.

[0156] In one realization, even if there is no indication for cause of inaccurate positioning estimates by LMF in the response message but it is indicated to AMF by LMF that the positioning method is used that of a single satellite (e.g., one TRP), the AMF may still decide not to deregister the UE, as shown at step 1275a of figure 12. A decision not to deregister the UE may comprise a decision to postpone deregistering the UE for a period of time. The period of time may be predetermined. The period of time may be set by an operator of the wireless communication network.

[0157] Figure 13 illustrates a method 1300 comprising additional messaging in NI-LR to determine the cause of inaccurate location estimates. The procedure 1300 is performed by a UE 1310, an NG-RAN node 1330, an AMF 1340 and an LMF 1320. When there is no indication from the LMF 1320 about the cause of inaccurate location estimates and is only indicated that method is used for single satellite, the AMF 1340 may further initiate request response messages to the LMF 1320 to determine the cause of inaccurate UE location estimates for a single satellite case. This process 1300 is illustrated in steps 1376 to 1379 of figure 13. Steps 1371 to 1375 are performed as per steps 1271 to 1275 respectively and as described above in relation to figure 12.

[0158] At 1376, the request message may include an indication to perform additional procedures to determine the cause of inaccuracy, i.e., the inaccuracy is due to technical limitation of the positioning method to estimate the UE location or for some other reason.

[0159] At 1377, upon receiving such request, the LMF 1320 would use additional procedures or other RAT-dependent positioning methods to determine an approximate UE location in a cell (that is, whether the UE 1310 is near the satellite orbital plane or not). The LMF 1320 may set a threshold from its orbital plane (e.g., + delta) for which the location method would cause an inaccuracy.

[0160] At 1378, if the LMF 1320 determines that UE location falls within that threshold value, the LMF 1320 generates a response message indicating that the cause of inaccuracy is due to the technical limitation of the method, as UE is located under/ near/ moving along the orbital plane. The LMF may also indicate the threshold value that are set for determining the technical limitations of the method.

[0161] The LMF 1320 may also include in the response message about the method type it used to determine that the UE 1310 is located in the uncertainty area and the location estimates may not be trusted for verification.

[0162] At 1379, upon receiving the response message, the AMF 1340 may not deregister the UE 1310, if the inaccuracy/ failure is due to the technical limitation of the positioning method.

[0163] Alternatively, LMF procedures may be used to determine a UE location near a ground track and/ or under orbital plane of a non-terrestrial network node.

[0164] The AMF 1340 may initiate an NG-RAN location estimate procedure to ask for UE GNSS position. The AMF 1340 may determine based on the GNSS position that the UE 1310 is near the satellite orbital plane or not. Based on this information and the indication by LMF that UE may only use a single satellite based positioning method.

Further, the AMF may decide not to deregister the UE, if the location estimates are determined to be inaccurate. Step 1379a shows that the UE 1310 may not be deregistered even if not verified. [0165] For example, based on a request/in dication from an external entity (e.g., AMF) or autonomously, the LMF may initiate UE location procedures to determine whether the UE is near/ under the satellite orbital plane or not. These procedures may either be performed in parallel to location estimate procedure that are used for some other purpose (e.g., location estimate for verification) or may be performed separately.

[0166] After determining that the target UE is in the coverage of one or multiple satellites, the LMF may determine which positioning method to use. In case of a single satellite, LMF may additionally decide to determine whether the UE is in the uncertainty area (location area near the orbital plane of satellite) or not. For example, the LMF may set the threshold value (e.g., ± delta from the orbital plane of a satellite) that falls under the uncertainty area of the satellite orbital plane, where the location estimates would always be determined to be inaccurate. The value may be predetermined. The value may be determined by the LMF based on the satellite height, speed etc. In one example, the value is indicated to the LMF by another network entity, i.e., AMF or NG-RAN node, whereas AMF may indicate this value along with verification flag in the location request message.

[0167] Upon receiving a location request from the AMF with a verification flag in the request message and after determining that target UE is in the coverage of single satellite, the LMF may first determine the target UE location using GNSS or any other RAT independent method. The LMF may also determine the ephemeris information of the serving satellite(s) from the NG-RAN node(s) by employing NRPPa protocol request/response messages (e.g., using TRP information exchange procedure or using request message to NG-RAN node to indicate the ephemeris information of the serving satellites). If the reported RAT independent position is near the orbital plane of the satellite with a predefined margin threshold value, the LMF would generate a failure cause indication along with satellite information (one or multiple satellites) in the response message to AMF that the location estimates cannot be accurate due to technical limitation.

[0168] Upon determining that the target UE is in the vicinity of a single satellite’s ground track, the LMF may configure resources such that the beam layout is adjusted in such a way that the uncertainty area lies under the intersection of at least two beams, as illustrated in Figure 12. In one implementation, PRS resources are used for this purpose, where the target UE may be configured with multiple PRS resources (e.g., multiple PRS may belong to same PRS resource ID or one PRS ID is associated with one resource set ID). The UE may perform measurements on multiple PRS and report RSRP for each of the PRS ID along with the PRS resource set ID. The configuration of PRS resources (e.g., in the assistance data) and the measurement reporting of multiple PRS may be part of the respective positioning methods to be used for the target UE location verification methods. For instance, if multi-RTT with single satellite is selected by LMF for positioning estimates, the LMF may configure multiple PRS resources to the target UE, for example in the IE NR-Mu d-RTT-PrvwdeAssistaticeData. The target UE may then perform measurements on the configures PRS resources associated with respective TRP ID and report back RSRP measurement for all the PRS IDs, for example in the IE NR- Multi- PT-SignalMeasurementlnformation. In one example, circular polarization types (i.e., LHCP and RHCP) are additionally associated with PRS-IDs to further reduce the inter beam interference.

[0169] Figure 14 illustrates an example of beam Layout of beam layout with FRF=3 to resolve geometrical limitations of time-based methods. Figure 14 shows the surface of the Earth 1400 with a ground track 1401 of a satellite orbit projected thereon, and the location of a UE 1410. A plurality of beam footprints 1460 are illustrated, labelled Beam ID 1, Beam ID 2, etc. (Adjacent beam IDs are illustrated with differently dashed lines to help differentiate them). The location of UE 1410 is shown within an area of overlap between Beam ID 1 and Beam ID 2.

[0170] Byway of example, beam ID 3 in figure 14 may be configured with LHCP, while beam ID 2 and 6 may use RHCP. In this case, the target UE 1410 reports polarization types along with PRS ID in the measurement report, e.g., in IE NR-Mudi-RTT- SignaUAeasurementlnformation for the case multi-RTT method. The LMF may determine based on the measurement results that target UE is located under the uncertainty area and the location estimates would be inaccurate or not. For example, if UE is located between beam ID 1 and beam 2 as in figure 14 and is configured to perform multi-RTT method measurements. The LMF would configure PRS resources according to beam layout in figure 14. The UE 1410 would perform measurements and report back beam ID 1 and beam ID 2 RSRP values. Based on the measurements, an LMF may determine that the UE 1410 is under the uncertainty area where inaccurate results may happen. The LMF may report back the location estimates and the reason that the results may be inaccurate due to UE position near the orbital plane.

[0171] Accordingly, there is provided a first network node comprising a processor and a memory coupled with the processor, the processor configured to cause the first network node to: receive a device location request configuration message from a second network node, wherein the device location configuration message comprises a request for an indication of a location estimate for the device; determine a first location estimate of the device by transmitting, from a non-terrestrial network node, a first positioning configuration message to the device; determine that the accuracy of the first location estimate does not meet a network location verification accuracy requirement; determine that the first location estimate is within a threshold distance of the ground track of the non-terrestrial network node; and transmit a location information response message to the second network node, wherein the location information response message includes an indication that the first location estimate is within a threshold distance of the ground track of the non-terrestrial network node.

[0172] The first network node may comprise an LMF. The second network node may be an AMF. The device may be a wireless communication device. The device may be a UE. The ground track is a path on the surface of the Earth directly below an aircraft or satellite trajectory. In the case of satellites, it is also known as a suborbital track, and is the vertical projection of the satellite’s orbit onto the surface of the Earth. The ground track may be referred to as the ground trace. Where the non-terrestrial network node is a satellite, the ground track may be defined as the line of intersection between an orbital plane of the satellite and the surface of the Earth. The threshold distance may be predefined by the network. The threshold distance may be configured to the first network node. The threshold distance may be configured to the first network node by a network operator. The non-terrestrial network node may comprise a satellite connected to an NG -RAN node via a gateway.

[0173] The processor may be further configured to cause the first network node to define an uncertainty threshold for the non-terrestrial network node, wherein the uncertainty threshold defines an acceptable level of accuracy for a location determination made using the non-terrestrial network node.

[0174] Where the non-terrestrial network comprises a plurality of non-terrestrial network nodes, then a respective uncertainty threshold may be determined for each nonterrestrial network node of the plurality of non-terrestrial network nodes.

[0175] The non-terrestrial network node may be a satellite and the uncertainty threshold is a threshold value derived from the satellite orbital plane. The threshold distance may define a maximum distance on each side of the satellite orbit plane. [0176] The processor may be further configured to cause the first network node to request flight path information for the non-terrestrial network node from the second network node, wherein the flight path information is used to determine the threshold distance. Where the non-terrestrial network node is a satellite, the flight path information may comprise satellite ephemeris information. The satellite ephemeris information may comprise height, velocity, and/or position.

[0177] The processor may be further configured to cause the first network node to receive the threshold distance from a third network node. The third network node may comprise an NG-RAN node.

[0178] The processor may be further configured to cause the first network node to determining a second location estimate of the device. The second location estimate may comprise a refinement of the first location estimate. Where the first location estimate comprises an area, the second location estimate may fall within the area of the first location estimate.

[0179] The second location estimate may be determined using a radio access technology dependent method. The second location estimate may be determined based on a positioning reference signal (PRS). The second location estimate may be determined using a radio access technology independent method. The radio access technology independent method may use a Global Navigation Satellite System (GNSS).

[0180] The processor may be further configured to cause the first network node to transmit an error indication to the second network node if an error level of the first location estimate exceeds an acceptable level of accuracy for a location determination made using the non-terrestrial network node.

[0181] The location information response message may include an indication of the threshold distance of the ground track of the non-terrestrial network node. A location information response message may include an indication of the method used for determining the second location estimate.

[0182] The processor may be further configured to cause the first network node to perform periodic, aperiodic, or semi-persistent location estimates for the device as a result of the first location estimate being within a threshold distance of the ground track of the non-terrestrial network node.

[0183] The processor may be further configured to cause the first network node to: determine that a revised first location estimate is beyond a threshold distance of the ground track of the non-terrestrial network node; and as a result of determining that a revised first location estimate is beyond a threshold distance of the ground track of the non-terrestrial network node, transmit a location information update message, the location information update message indicating that the revised first location estimate is beyond a threshold distance of the ground track of the non-terrestrial network node. [0184] Figure 15 illustrates a method 1500 performed by a first network node. The method 1500 comprises: receiving 1510 a device location request configuration message from a second network node, wherein the device location configuration message comprises a request for an indication of a location estimate for the device; determining 1520 a first location estimate of the device by transmitting, from a non-terrestrial network node, a first positioning configuration message to the device; determining 1530 that the accuracy of the first location estimate does not meet a network location verification accuracy requirement; determining 1540 that the first location estimate is within a threshold distance of the ground track of the non-terrestrial network node; and transmitting 1550 a location information response message to the second network node, wherein the location information response message includes an indication that the first location estimate is within a threshold distance of the ground track of the non-terrestrial network node.

[0185] In certain embodiments, the method 1500 may be performed by a processor executing program code, for example, a microcontroller, a microprocessor, a CPU, a GPU, an auxiliary processing unit, a FPGA, or the like.

[0186] The first network node may comprise an LMF. The second network node may be an AMF. The device may be a wireless communication device. The device may be a UE. The ground track is a path on the surface of the Earth directly below an aircraft or satellite trajectory. In the case of satellites, it is also known as a suborbital track, and is the vertical projection of the satellite’s orbit onto the surface of the Earth. The ground track may be referred to as the ground trace. Where the non-terrestrial network node is a satellite, the ground track may be defined as the line of intersection between an orbital plane of the satellite and the surface of the Earth. The threshold distance may be predefined by the network. The threshold distance may be configured to the first network node. The threshold distance may be configured to the first network node by a network operator.

[0187] The non-terrestrial network node comprises a satellite connected to an NG-RAN node via a gateway. The method may further comprise defining an uncertainty threshold for the non-terrestrial network node, wherein the uncertainty threshold defines an acceptable level of accuracy for a location determination made using the non-terrestrial network node. Where the non-terrestrial network comprises a plurality of non-terrestrial network nodes, then a respective uncertainty threshold may be determined for each nonterrestrial network node of the plurality of non-terrestrial network nodes.

[0188] The non-terrestrial network node may be a satellite and the uncertainty threshold is a threshold value derived from the satellite orbital plane. The threshold distance may define a maximum distance on each side of the satellite orbit plane.

[0189] The first network node may request flight path information for the non-terrestrial network node from the second network node, wherein the flight path information is used to determine the threshold distance. Where the non-terrestrial network node is a satellite, the flight path information may comprise satellite ephemeris information. The satellite ephemeris information may comprise height, velocity, and/ or position. The method may further comprise receiving the threshold distance from a third network node. The third network node may comprise an NG-RAN node.

[0190] The method may further comprise determining a second location estimate of the device. The second location estimate may comprise a refinement of the first location estimate. Where the first location estimate comprises an area, the second location estimate may fall within the area of the first location estimate.

[0191] The second location estimate may be determined using a radio access technology dependent method. The second location estimate may be determined based on a positioning reference signal (PRS).

[0192] The second location estimate may be determined using a radio access technology independent method. The radio access technology independent method may use a Global Navigation Satellite System (GNSS).

[0193] The method may further comprise transmitting an error indication to the second network node if an error level of the first location estimate exceeds an acceptable level of accuracy for a location determination made using the non-terrestrial network node.

[0194] The location information response message may include an indication of the threshold distance of the ground track of the non-terrestrial network node. A location information response message may include an indication of the method used for determining the second location estimate.

[0195] The method may further comprise performing periodic, aperiodic, or semi- persistent location estimates for the device as a result of the first location estimate being within a threshold distance of the ground track of the non-terrestrial network node. [0196] The method may further comprise: determining that a revised first location estimate is beyond a threshold distance of the ground track of the non-terrestrial network node; and as a result of determining that a revised first location estimate is beyond a threshold distance of the ground track of the non-terrestrial network node, transmitting a location information update message, the location information update message indicating that the revised first location estimate is beyond a threshold distance of the ground track of the non-terrestrial network node.

[0197] There is further provided a second network node comprising a processor; and a memory coupled with the processor, the processor configured to cause the second network node to: transmit a device location request configuration message to a first network node, wherein the device location configuration message comprises a request for an indication of a location estimate for the device; and receive a location information response message from the first network node, wherein the location information response message includes an indication that the first location estimate is within a threshold distance of the ground track of the non-terrestrial network node.

[0198] The first network node may comprise an LMF. The second network node may be an AMF. The device may be a wireless communication device. The device may be a UE. The ground track is a path on the surface of the Earth directly below an aircraft or satellite trajectory. In the case of satellites, it is also known as a suborbital track, and is the vertical projection of the satellite’s orbit onto the surface of the Earth. The ground track may be referred to as the ground trace. Where the non-terrestrial network node is a satellite, the ground track may be defined as the line of intersection between an orbital plane of the satellite and the surface of the Earth. The threshold distance may be predefined by the network. The threshold distance may be configured to the first network node. The threshold distance may be configured to the first network node by a network operator.

[0199] The processor may be further configured to cause the second network node to perform a verification process of the location information for the device based on the received location information response message.

[0200] The device location request configuration message may comprise an indication of a number of non-terrestrial network nodes that are currently providing coverage to the device location. The device location request configuration message may comprise an indication of the threshold distance of the ground track of the non-terrestrial network node. [0201] The processor may be further configured to cause the second network node to accept a registration of the device if the first location estimate is within a threshold distance of the ground track of the non-terrestrial network node. The processor may be further configured to cause the second network node to repeat a new network induced location reporting procedure for the device if the first location estimate is within a threshold distance of the ground track of the non-terrestrial network node, wherein the repetition is periodic, aperiodic, or semi persistent.

[0202] The processor may be further configured to cause the second network node to: transmit a new request message to the first network node in response to the location information response message indicating that the accuracy of the first location estimate exceeds a threshold; receive a new location information response message from the first network node, wherein the new location information response message comprises an indication of the cause of the accuracy of the first location estimate exceeding the threshold; and perform a verification process using the first location estimate based on the received new location information response message.

[0203] Figure 16 illustrates a method 1600 performed by a second network node. The method 1600 comprises: transmitting 1610 a device location request configuration message to a first network node, wherein the device location configuration message comprises a request for an indication of a location estimate for the device; and receiving 1620 a location information response message from the first network node, wherein the location information response message includes an indication that the first location estimate is within a threshold distance of the ground track of the non-terrestrial network node.

[0204] In certain embodiments, the method 1600 may be performed by a processor executing program code, for example, a microcontroller, a microprocessor, a CPU, a GPU, an auxiliary processing unit, a FPGA, or the like.

[0205] The first network node may comprise an LMF. The second network node may be an AMF. The device may be a wireless communication device. The device may be a UE. The ground track is a path on the surface of the Earth directly below an aircraft or satellite trajectory. In the case of satellites, it is also known as a suborbital track, and is the vertical projection of the satellite’s orbit onto the surface of the Earth. The ground track may be referred to as the ground trace. Where the non-terrestrial network node is a satellite, the ground track may be defined as the line of intersection between an orbital plane of the satellite and the surface of the Earth. The threshold distance may be predefined by the network. The threshold distance may be configured to the first network node. The threshold distance may be configured to the first network node by a network operator.

[0206] The method may further comprise performing a verification process of the location information for the device based on the received location information response message.

[0207] The device location request configuration message may comprise an indication of a number of non-terrestrial network nodes that are currently providing coverage to the device location. The device location request configuration message may comprise an indication of the threshold distance of the ground track of the non-terrestrial network node.

[0208] The method may further comprise accepting a registration of the device if the first location estimate is within a threshold distance of the ground track of the nonterrestrial network node. The method may further comprise repeating a new network induced location reporting procedure for the device if the first location estimate is within a threshold distance of the ground track of the non-terrestrial network node, wherein the repetition is periodic, aperiodic, or semi persistent.

[0209] The method may further comprise: transmitting a new request message to the first network node in response to the location information response message indicating that the accuracy of the first location estimate exceeds a threshold; receiving a new location information response message from the first network node, wherein the new location information response message comprises an indication of the cause of the accuracy of the first location estimate exceeding the threshold; and performing a verification process using the first location estimate based on the received new location information response message.

[0210] The conclusions of 3GPP TR 38.882 vl8.0.0 have identified the need to define a network-based solution which aims at verifying the reported UE location information. In Rel-18, the network induced location reporting (NI-LR) procedure was adopted in NTN to verify the reported UE location information. The positioning techniques in 3GPP are developed by considering the typical scenarios in terrestrial networks, where measurements from at least three gNBs are usually used for location estimates. However, such scenarios may be hard to find in NTNs as one of the common scenarios in NTN is that the UEs are usually in the coverage area of a single satellite. Therefore, the existing positioning methods may need be adapted in cases where the UE is in the coverage area of a single satellite. One such adaptation for time based methods may be to utilize the movement of NGSO satellites, i.e., by performing the measurements at multiple time instances from the same satellite. However, such methodology may still result in some limitations and low accurate location estimates.

[0211] For instance, if the UEs are located along and/ or near the orbital plane of a satellite coverage area (i.e., NGSO satellites) and are connected to NG-RAN through that single satellite, the positioning accuracy would always be lower than the predefined accuracy threshold for verification, i.e., 5—10 km. Therefore, the UEs located near the orbital plane may not be able to verify their location due to radio and satellite geometrical limitations of the positioning methods. In such a case, these UEs may always be deregistered from network, even though these UEs may be valid UEs but have to be deregistered for not fulfilling the accuracy threshold due to the technical NTN limitations of time-based positioning methods.

[0212] The present disclosure provides a set of procedural enhancements to address the verification procedure for those UEs that are located near the orbital plane of a satellite and are in the coverage area of that satellite.

[0213] Accordingly, the present disclosure provides enhancements for enabling network verified location of the target-UE that are located near the satellite orbital plane such that these UEs may not be deregistered if they are valid UEs. For instance, the verification procedure may be optional for UEs that have technical limitations, where AMF, based on explicit or implicit indications, would need to determine that UEs are located near the satellite orbit. This may require enhancements to NI-LR procedure to verify and determine by AMF that UE is located near the satellite orbital plane.

[0214] The AMF may not deregister UEs that do not fulfil accuracy requirements for verification, if AMF determines either based on explicit or implicit indication that UEs are located near the orbital plane and the accuracy threshold are not met because of technical limitations of the positioning method employed, or AMF employs additional procedures to determine the cause of inaccurate position estimates in case of single estimates.

[0215] Based on a request/in dication from an external entity (e.g., AMF) or autonomously, LMF initiates UE location procedures to determine that UE is near/ under the satellite orbital plane or not. These procedures may either be performed in parallel to location estimate procedure that are used for some other purpose (e.g., location estimate for verification) or may be performed separately. [0216] Accordingly, there is provided a method of a first network entity apparatus [i.e., LMF], comprising: receiving a user equipment (“UE”) location request configuration message from a second network entity [i.e., AMF], wherein, the location configuration comprises at least an indication for location estimates for UE location verification; determining the location of the UE with a certain accuracy by initiating a location estimation procedure for the UE based on the location request configuration message; determining that the location estimate accuracy of the UE does not meet the network location verification accuracy requirements; determining the cause of inaccurate location estimates for UEs for a given NTN deployment; transmitting a location information response to the second network entity, wherein the location response comprises at least of an error indication about a UE’s location in the vicinity of the satellite orbital plane. [0217] The NTN deployment may comprise of single satellite connected to an NG- RAN node via a gateway.

[0218] The method may further comprise defining an uncertainty area for single satellites based location estimate methods where the location estimates from a positioning method may always generate an inaccurate estimate for verification.

[0219] The uncertainty area may be defined by a threshold value from the satellite orbital plane.

[0220] The threshold value may define the maximum distance on both sides of the satellite orbit plane.

[0221] The first network entity [i.e., LMF] requests satellite ephemeris information [i.e., height, velocity, position] from the second network entity [i.e., NG-RAN node] to determine the threshold value.

[0222] The method may further comprise receiving the threshold value of the uncertainty area from another network entity [i.e., NG-RAN node].

[0223] The method may further comprise determining the location of a UE in the uncertainty area.

[0224] The location of a UE in the uncertainty area is estimated using RAT-dependent methods.

[0225] The location of a UE in the uncertainty area may be estimated based on PRS- IDs.

[0226] The location of a UE in the uncertainty area may be estimated using RAT- independent methods [e.g., GNSS]. [0227] The method may further comprise transmitting a location failure or error indication if a UE is in the uncertainty area.

[0228] The location information response message may include an indication about the threshold values for uncertainty area.

[0229] The location information response message may include an indication about the type of method used for determining the UE location in the uncertainty area.

[0230] The method may further comprise performing periodic, aperiodic, or semi- persistent location estimates for UEs in the uncertainty areas.

[0231] The method may further comprise initiating a new response message, indicating when a UE moves out of uncertainty area.

[0232] There is further provided a method of a first network entity apparatus [i.e., AMF], the method comprising: transmitting a user equipment (“UE”) location request configuration to a second network entity [i.e., LMF], wherein, the location configuration comprises at least an indication for location estimates for verification; receiving a location information response from the second network entity, wherein the location response comprises at least of an explicit or implicit indication about UE location near the satellite orbital plane; performing a verification process of the location information for the UE based on the received location response.

[0233] The location configuration request message may comprise an indication of number of satellites that are providing coverage to the target UE.

[0234] The location configuration request message may comprise of an indication about the uncertainty area for single satellite based location estimates.

[0235] The location configuration response message may comprise an indication of number of satellites that are providing coverage to the target UE.

[0236] The method may comprise not performing verification process based on single satellite indication in the response message.

[0237] The method may comprise not deregistering the UEs in the uncertainty area based on the indication in the response message.

[0238] The method may further comprise repeating a new network induced location reporting procedure for the UEs in the uncertainty area, whereas the repetition may be periodic, aperiodic, or semi persistent.

[0239] The method may further comprise: transmitting a new request message to a second network entity [i.e., LMF] in response to an inaccurate location estimate with a single satellite, wherein, the request message includes an indication to determine the cause of the inaccurate location estimate; receiving a location information response from the second network entity, wherein the location response comprises the cause of inaccurate location estimates; and performing a verification process of the location information for the UE based on the received location response.

[0240] It should be noted that the above-mentioned methods and apparatus illustrate rather than limit the invention, and that those skilled in the art will be able to design many alternative arrangements without departing from the scope of the appended claims. The word “comprising” does not exclude the presence of elements or steps other than those listed in a claim, “a” or “an” does not exclude a plurality, and a single processor or other unit may fulfil the functions of several units recited in the claims. Any reference signs in the claims shall not be construed so as to limit their scope.

[0241] Further, while examples have been given in the context of particular communication standards, these examples are not intended to be the limit of the communication standards to which the disclosed method and apparatus may be applied. For example, while specific examples have been given in the context of 3GPP, the principles disclosed herein can also be applied to another wireless communication system, and indeed any communication system which uses routing rules.

[0242] The method may also be embodied in a set of instructions, stored on a computer readable medium, which when loaded into a computer processor, Digital Signal Processor (DSP) or similar, causes the processor to carry out the hereinbefore described methods.

[0243] The described methods and apparatus may be practiced in other specific forms. The described methods and apparatus are to be considered in all respects only as illustrative and not restrictive. The scope of the invention is, therefore, indicated by the appended claims rather than by the foregoing description. All changes which come within the meaning and range of equivalency of the claims are to be embraced within their scope.

The following abbreviations are relevant in the field addressed by this document: A GNSS, Assisted GNSS; ARFCN, Absolute Radio Frequency Channel Number; ARP, Antenna Reference Point; BFD, Beam failure detection; BSSID, Basic Service Set Identifier; BTS, Base Transceiver Station (GERAN); BWP, Bandwidth Part; CID, Cell- ID (positioning method); DCI, Downlink Control Information; DL, Downlink; DL- AoD, Downlink Angle-of-Departure; DL-TDOA, Downlink Time Difference Of Arrival; DM-RS, DeModulation Reference Signal; ECEF, Earth-Centered, Earth-Fixed; ECGI, Evolved Cell Global Identifier; E CID, Enhanced Cell-ID (positioning method); EIRE, Equivalent Isotropic Radiated Power; E-SMLC, Enhanced Serving Mobile Location Centre; E-UTRAN, Evolved Universal Terrestrial Radio Access Network;

EPDU, External Protocol Data Unit; FDMA, Frequency Division Multiple Access; FRF, Frequency Reuse Factor; FSS, Fixed Satellite Services; FTA, Fine Time Assistance;

GAGAN, GPS Aided Geo Augmented Navigation; GEO, Geostationary Earth Orbiting; GMLC, Gateway Mobile Location Centre; GNSS, Global Navigation Satellite System; GPS, Global Positioning System; GW, Gateway; HAPS, High Altitude Platform Station; HA GNSS, High-Accuracy GNSS (RTK, PPP); HPLMN, Home Public Land Mobile Network; HEO, Highly Elliptical Orbiting; IMU, Inertial Measurement Unit; IS, Interface Specification; ISL, Inter- Satellite Links; LEO, Low Earth Orbiting; LMC, Location Management Component; LMF, Location Management Function; LMU, Location Management Unit; LOS, Line-of-sight; LPP, LTE Positioning Protocol; MAC CE, Medium Access Control Element; MBS, Metropolitan Beacon System; MG, Measurement Gap; MGL, Measurement Gap Length; MGRP, Measurement Gap Repetition Period; MO-LR, Mobile Originated Location Request; MEO, Medium Earth Orbiting; MS, Mobile Services; MSS, Mobile Satellite Services; MSB, Most Significant Bit; MT-LR, Mobile Terminated Location Request; Multi-RTT, Multiple-Round Trip Time; NB-IoT, NarrowBand Internet of Things; NCGI, NR Cell Global Identifier ; NI-LR, Network Induced Location Request; NLOS, Non-line-of-sight; NPRS, Narrowband Positioning Reference Signals; NR, NR Radio Access; NRPPa, NR Positioning Protocol Annex; NRSRP, Narrowband Reference Signal Received Power; NRSRQ, Narrowband Reference Signal Received Quality; OSR, Observation Space Representation; OTDOA, Observed Time Difference Of Arrival; PDU, Protocol Data Unit; PDCCH, Physical Downlink Control Channel; PDSCH, Physical Downlink Shared Channel; PRB, Physical Resource Block; PRS, Positioning Reference Signals; posSIB, Positioning System Information Block; PT-RS, Phase Tracking Reference Signal; PUCCH, Physical Uplink Control Channel; PUSCH, Physical Uplink Shared Channel; QCL, Quasi Co-Location; RAT, Radio Access Technology; RF, Radio Frequency; P-RNTI, Paging-Radio Network Temporary Identifier; RRC, Radio Resource Control; RRM, Radio Resource Management; RS, Reference Signal; RSRP, Reference Signal Received Power; RSRQ, Reference Signal Received Quality; RSTD, Reference Signal Time Difference; RSU, Roadside Unit; RTK, Real-Time Kinematic; RTT, Round Trip Time; SBAS, Space Based Augmentation System; SFN, System Frame Number; SL, Sidelink; SL-PRS, Sidelink Positioning Reference Signal; SLP, SUPL Location Platform; SMTC, SSB-based Measurement Timing configuration; SS/PBCH, Synchronization Signal/Physical Broadcast Channel; SSBRI, SS/PBCH Block Resource Index; SSID, Service Set Identifier; SSR, State Space Representation; SUPL, Secure User Plane Location; TBS, Terrestrial Beacon System; TOA, Time Of Arrival; TP, Transmission Point; TRP, Transmission-Reception Point; UE, User Equipment; UL , Uplink; VPLMN, Visited Public Land Mobile Network; WGS 84, World Geodetic System 1984; and WLAN, Wireless Local Area Network.