Network-based location verification using uplink synchronization metrics in non-terrestrial networks

Abstract

Techniques for operating the NTN include comparing a behavior of a measured rate of time change of a timing advance error (carrier frequency error) to a predicted behavior of a rate of time change of the timing advance error (carrier frequency error). Specifically, when taking into account the frequency at which the user equipment accesses ephemeris information, this behavior may be determined by analyzing the rate of change in time (or change relative to elevation) of a timing advance error or carrier frequency error, and comparing this behavior to a predicted behavior that differs significantly in the reported position of the user equipment.

Description

Technical Field

[0001] This specification relates to telecommunication systems. Background Art

[0002] A communication system may be a facility that enables communication between two or more nodes or devices, such as fixed or mobile communication equipment. Signals may be carried on wired or wireless carriers.

[0003] An example of a cellular communication system is an architecture standardized by the Third Generation Partnership Project (3GPP). Recent developments in the art are generally referred to as the Long Term Evolution (LTE) of the Universal Mobile Telecommunications System (UMTS) radio access technology. E-UTRA (Evolved UMTS Terrestrial Radio Access) is the air interface of the LTE upgrade path of 3GPP for mobile networks. In LTE, a base station or access point (AP) referred to as an enhanced node AP (eNB) provides wireless access within a coverage area or cell. In LTE, a mobile device or mobile station is referred to as a user equipment (UE). LTE has included many improvements or developments.

[0004] For example, the global bandwidth shortage for wireless carriers has stimulated the consideration of underutilized millimeter wave (mmWave) spectrum for future broadband cellular communication networks. mmWave (or extremely high frequency) may, for example, include a frequency range between 30 and 300 gigahertz (GHz). The radio waves in this band may, for example, have a wavelength from ten millimeters to one millimeter, which is named millimeter band or millimeter wave. The amount of wireless data will likely increase significantly in the next few years. Various technologies have been used to try to solve this challenge, including obtaining more spectrum, having a smaller cell size, and using improved technologies that enable more bits / second / hertz. One element that can be used to obtain more spectrum is to move to higher frequencies, such as above 6GHz. For the fifth generation wireless system (5G), an access architecture for deploying cellular radio equipment using mmWave radio spectrum has been proposed. Other example spectrums, such as cmWave radio spectrum (e.g., 3-30GHz), can also be used. Summary of the invention

[0005] According to an example implementation, a method includes: receiving, by a network node of a non-terrestrial network, a plurality of transmissions from a user equipment in the non-terrestrial network, the plurality of transmissions carrying reported positioning data representing a reported position of the user equipment; determining, by the network node, a corresponding error of a measured uplink transmission time from a predicted uplink transmission time, the measured uplink transmission time being based on the reported position of the user equipment; performing, by the network node, a comparison between: a received time rate of change of the measured uplink transmission time and the corresponding error of the predicted uplink transmission time, and an expected time rate of change of the measured uplink transmission time and the corresponding error of the predicted uplink transmission time; and sending, by the network node, response indication data to the user equipment, the response indication data representing an indication of an action to be taken by the user equipment, the indication being based on the comparison.

[0006] According to an example implementation, a device comprises: at least one processor and at least one memory, including computer program code, the at least one memory and the computer program code being configured to, together with the at least one processor, cause the device to at least: receive, by a network node of a non-terrestrial network, a plurality of transmissions from a user equipment in the non-terrestrial network, the plurality of transmissions carrying reported positioning data representing a reported position of the user equipment; determine, by the network node, a corresponding error of a measured uplink transmission time from a predicted uplink transmission time, the measured uplink timing advance being based on the reported position of the user equipment; perform, by the network node, a comparison between: a received time rate of change of the measured uplink transmission time and the corresponding error of the predicted uplink transmission time, and an expected time rate of change of the measured uplink transmission time and the corresponding error of the predicted uplink transmission time; and send, by the network node, response indication data to the user equipment, the response indication data representing an indication of an action to be taken by the user equipment, the indication being based on the comparison.

[0007] According to an example implementation, an apparatus comprises: a component for receiving, by a network node of a non-terrestrial network, a plurality of transmissions from a user equipment in the non-terrestrial network, the plurality of transmissions carrying reported positioning data representing a reported position of the user equipment; a component for determining, by the network node, a corresponding error of a measured uplink transmission time from a predicted uplink transmission time, the measured uplink transmission time being based on the reported position of the user equipment; a component for performing, by the network node, a comparison between: a received time rate of change of the measured uplink transmission time and the corresponding error of the predicted uplink transmission time, and an expected time rate of change of the measured uplink transmission time and the corresponding error of the predicted uplink transmission time; and a component for sending, by the network node, response indication data to the user equipment, the response indication data representing an indication of an action to be taken by the user equipment, the indication being based on the comparison.

[0008] According to an example implementation, a computer program product includes a computer-readable storage medium and stores executable code, which, when executed by at least one data processing device, is configured to cause the at least one data processing device to: receive, by a network node of a non-terrestrial network, a plurality of transmissions from a user equipment in the non-terrestrial network, the plurality of transmissions carrying reported positioning data representing a reported position of the user equipment; determine, by the network node, a corresponding error of a measured uplink transmission time from a predicted uplink transmission time, the measured uplink timing advance being based on the reported position of the user equipment; perform, by the network node, a comparison between: a received time rate of change of the measured uplink transmission time and the corresponding error of the predicted uplink transmission time, and an expected time rate of change of the measured uplink transmission time and the corresponding error of the predicted uplink transmission time; and send, by the network node, response indication data to the user equipment, the response indication data representing an indication of an action to be taken by the user equipment, the indication being based on the comparison.

[0009] According to an example implementation, a method includes: receiving, by a network node of a non-terrestrial network, a plurality of transmissions from a user equipment in the non-terrestrial network, the plurality of transmissions carrying reported positioning data representing a reported position of the user equipment; determining, by the network node, a corresponding error of a measured uplink carrier frequency from a predicted uplink carrier frequency, the measured uplink carrier frequency being based on the reported position of the user equipment; performing, by the network node, a comparison between: a received time rate of change of the measured uplink carrier frequency and the corresponding error of the predicted uplink carrier frequency, and an expected time rate of change of the measured uplink carrier frequency and the corresponding error of the predicted uplink carrier frequency; and sending, by the network node, response indication data to the user equipment, the response indication data representing an indication of an action to be taken by the user equipment, the indication being based on the comparison.

[0010] According to an example implementation, a device comprises: at least one processor and at least one memory, including computer program code, the at least one memory and the computer program code being configured to, together with the at least one processor, cause the device to at least: receive, by a network node of a non-terrestrial network, a plurality of transmissions from a user equipment in the non-terrestrial network, the plurality of transmissions carrying reported positioning data representing a reported position of the user equipment; determine, by the network node, a corresponding error of a measured uplink carrier frequency from a predicted uplink carrier frequency, the measured uplink carrier frequency being based on the reported position of the user equipment; perform, by the network node, a comparison between: a received time rate of change of the measured uplink carrier frequency and the corresponding error of the predicted uplink carrier frequency, and an expected time rate of change of the measured uplink carrier frequency and the corresponding error of the predicted uplink carrier frequency; and send, by the network node, response indication data to the user equipment, the response indication data representing an indication of an action to be taken by the user equipment, the indication being based on the comparison.

[0011] According to an example implementation, an apparatus comprises: a component for receiving, by a network node of a non-terrestrial network, a plurality of transmissions from a user equipment in the non-terrestrial network, the plurality of transmissions carrying reported positioning data representing a reported position of the user equipment; a component for determining, by the network node, a corresponding error of a measured uplink carrier frequency from a predicted uplink carrier frequency, the measured uplink carrier frequency being based on the reported position of the user equipment; a component for performing, by the network node, a comparison between: a received time rate of change of the measured uplink carrier frequency and the corresponding error of the predicted uplink carrier frequency, and an expected time rate of change of the measured uplink carrier frequency and the corresponding error of the predicted uplink carrier frequency; and a component for sending, by the network node, response indication data to the user equipment, the response indication data representing an indication of an action to be taken by the user equipment, the indication being based on the comparison.

[0012] According to an example implementation, a computer program product includes a computer-readable storage medium and stores executable code, which, when executed by at least one data processing device, is configured to: receive, by a network node of a non-terrestrial network, a plurality of transmissions from a user equipment in the non-terrestrial network, the plurality of transmissions carrying reported positioning data representing a reported position of the user equipment; determine, by the network node, a corresponding error of a measured uplink carrier frequency from a predicted uplink carrier frequency, the measured uplink carrier frequency being based on the reported position of the user equipment; perform, by the network node, a comparison between: a received time rate of change of the measured uplink carrier frequency and the corresponding error of the predicted uplink carrier frequency, and an expected time rate of change of the measured uplink carrier frequency and the corresponding error of the predicted uplink carrier frequency; and send, by the network node, response indication data to the user equipment, the response indication data representing an indication of an action to be taken by the user equipment, the indication being based on the comparison.

[0013] According to an example implementation, a method includes: receiving, by an orbiting satellite of a non-terrestrial network, a plurality of transmissions from a user device in the non-terrestrial network, the plurality of transmissions carrying reported positioning data representing a reported position of the user device; sending, by the orbiting satellite, the plurality of transmissions carrying the reported positioning data to a network node of the non-terrestrial network; receiving, by the orbiting satellite, response indication data representing an indication of an action to be taken with respect to the user device from the network node; and sending, by the orbiting satellite, action data representing an action to be taken with respect to the user device to the user device.

[0014] According to an example implementation, an apparatus comprises: at least one processor and at least one memory, including computer program code, the at least one memory and the computer program code being configured to, together with the at least one processor, cause the apparatus to at least: receive, by an orbiting satellite of a non-terrestrial network, a plurality of transmissions from a user device in the non-terrestrial network, the plurality of transmissions carrying reported positioning data representing a reported position of the user device; send, by the orbiting satellite, a plurality of transmissions carrying the reported positioning data to a network node of the non-terrestrial network; receive, by the orbiting satellite, response indication data representing an indication of an action to be taken by the user device from the network node; and send, by the orbiting satellite, action data representing an action to be taken by the user device to the user device.

[0015] According to an example implementation, an apparatus includes: a component for receiving, by an orbiting satellite of a non-terrestrial network, a plurality of transmissions from a user device in the non-terrestrial network, the plurality of transmissions carrying reported positioning data representing a reported position of the user device; a component for sending, by the orbiting satellite, the plurality of transmissions carrying the reported positioning data to a network node of the non-terrestrial network; a component for receiving, by the orbiting satellite, response indication data representing an indication of an action to be taken by the user device from the network node; and a component for sending, by the orbiting satellite, action data representing an action to be taken by the user device to the user device.

[0016] According to an example implementation, a computer program product includes a computer-readable storage medium and stores executable code, which, when executed by at least one data processing device, is configured to: receive, by an orbiting satellite of a non-terrestrial network, a plurality of transmissions from a user equipment in the non-terrestrial network, the plurality of transmissions carrying reported positioning data representing a reported position of the user equipment; send, by the orbiting satellite, a plurality of transmissions carrying the reported positioning data to a network node of the non-terrestrial network; receive, by the orbiting satellite, response indication data representing an indication of an action to be taken by the user equipment from the network node; and send, by the orbiting satellite, action data representing an action to be taken by the user equipment to the user equipment.

[0017] According to an example implementation, a method includes: sending, by a user equipment in a non-terrestrial network, a plurality of transmissions to a network node of the non-terrestrial network, the plurality of transmissions carrying reported positioning data representing a reported position of the user equipment, the reported position of the user equipment being different from an actual position of the user equipment at a corresponding moment in time; and receiving, by the user equipment from the network node, an instruction to remove the user equipment from the non-terrestrial network.

[0018] According to an example implementation, an apparatus comprises: at least one processor and at least one memory, including computer program code, the at least one memory and the computer program code being configured to, together with the at least one processor, cause the apparatus to at least: send, by a user equipment in a non-terrestrial network, a plurality of transmissions to a network node of the non-terrestrial network, the plurality of transmissions carrying reported positioning data representing a reported position of the user equipment; and receive, by the user equipment, from the network node, an instruction for removing the user equipment from the non-terrestrial network.

[0019] According to an example implementation, an apparatus includes: components for sending, by a user equipment in a non-terrestrial network, a plurality of transmissions to a network node of the non-terrestrial network, the plurality of transmissions carrying reported positioning data representing a reported position of the user equipment, the reported position of the user equipment being different from an actual position of the user equipment at a corresponding moment; and components for receiving, by the user equipment, from the network node, an instruction to remove the user equipment from the non-terrestrial network.

[0020] According to an example implementation, a computer program product includes a computer-readable storage medium and stores executable code, which, when executed by at least one data processing device, is configured to: send, by a user equipment in a non-terrestrial network, a plurality of transmissions to a network node of the non-terrestrial network, the plurality of transmissions carrying reported positioning data representing a reported position of the user equipment; and receive, by the user equipment from the network node, an instruction for removing the user equipment from the network node of the non-terrestrial network.

[0021] The details of one or more examples of implementations are set forth in the accompanying drawings and the description below. Other features will be apparent from the description and drawings, and from the claims. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 is a block diagram of a digital communication network according to an example implementation.

[0023] Figure 2 is a diagram illustrating a 3GPP NTN system based on a transparent architecture including a serving link and a feeder link according to an example implementation.

[0024] Figure 3 is a diagram showing a LEO satellite at a speed V according to an example implementation. S The UE moves at a speed V U Moving diagram; the elevation angle of the satellite relative to the UE is θ.

[0025] Figure 4A is a graph showing serving link TA as a function of elevation angle θ for a LEO satellite at 600 km altitude and 2 GHz carrier frequency according to an example implementation.

[0026] Figure 4Bis a graph showing serving link Doppler shift as a function of elevation angle θ for a LEO satellite at 600 km altitude and 2 GHz carrier frequency according to an example implementation.

[0027] Figure 5 is a diagram illustrating a scenario in which a UE uses its true (eg, GNSS-based) location to access an NTN network but reports an erroneous location to the network, according to an example implementation.

[0028] Fig. 6A is a graph further illustrating the timing advance error in the serving link as a function of elevation angle during a satellite flyby.According to an example implementation, it is assumed that the UE reads the ephemeris information every 3s.

[0029] Figure 6B is a graph further illustrating the carrier frequency error in the serving link as a function of elevation angle during a satellite flyby. According to an example implementation, it is assumed that the UE reads the ephemeris information every 3s.

[0030] Fig. 7A is a graph further illustrating the timing advance error in the serving link as a function of the elevation angle during a satellite flyby. It is assumed that the UE reads the ephemeris information every 10 s.

[0031] Figure 7B is a graph further illustrating the carrier frequency error in the serving link as a function of elevation angle during a satellite flyby. It is assumed that the UE reads the ephemeris information every 10 s.

[0032] Figure 8 is a flow chart illustrating a process of determining whether a user equipment is providing an erroneous location to an NTN according to an example implementation.

[0033] Fig. 9 is a flow chart illustrating a process of determining whether a user equipment is providing an erroneous location to an NTN according to an example implementation.

[0034] Fig.10 is a flow chart illustrating a process of determining whether a user equipment is providing an erroneous location to an NTN according to an example implementation.

[0035] Fig.11 is a flow chart illustrating a process of determining whether a user equipment is providing an erroneous location to an NTN according to an example implementation.

[0036] Fig.12 is a block diagram of a node or wireless station (eg, a base station / access point, a relay node, or a mobile station / user equipment) according to an example implementation. DETAILED DESCRIPTION

[0037] The principles of the present disclosure will now be described with reference to some example embodiments. It should be understood that these embodiments are described for illustrative purposes only and to help those skilled in the art understand and implement the present disclosure, and are not intended to limit the scope of the present disclosure in any way. The disclosure described herein can be implemented in various ways except as follows.

[0038] The terms used herein are only used for the purpose of describing specific embodiments and are not intended to limit the exemplary embodiments. As used herein, the singular forms "a", "an", and "the" are also intended to include their plural forms unless the context clearly indicates otherwise. It will also be understood that the terms "include", "comprise", "have", "have", "include" and / or "comprising" etc. when used herein specify the presence of features, elements and / or components, etc., but do not exclude the presence or increase of one or more other features, elements, components and / or combinations thereof.

[0039] Figure 1 is a block diagram of a digital communication system, such as wireless network 130, according to an example implementation. Figure 1 In a wireless network 130, user equipment 131, 132 and 133 (which may also be referred to as mobile stations (MS) or user devices (UE)) can be connected to (and communicate with) a base station (BS) 134 (which may also be referred to as an access point (AP), an enhanced node B (eNB), a gNB (which may be a 5G base station or network node)). At least a portion of the functions of an access point (AP), a base station (BS) or an (e) node B (eNB) may also be performed by any node, server or host that is operably coupled to a transceiver, such as a remote radio head. BS (or AP) 134 provides wireless coverage within a cell 136, which includes user equipment 131, 132 and 133. Although only three user equipment are shown connected or attached to BS 134, any number of user equipment may be provided. BS 134 is also connected to a core network 150 via an interface 151. This is just a simple example of a wireless network, and other examples may be used.

[0040] User equipment (user terminal, user equipment (UE)) may refer to a portable computing device including a wireless mobile communication device operating with or without a subscriber identity module (SIM), including but not limited to the following types of devices: mobile station (MS), mobile phone, cellular phone, smart phone, personal digital assistant (PDA), handheld, equipment using a wireless modem (alarm or measurement equipment, etc.), laptop and / or touch screen computer, tablet computer, phablet, game console, notebook, vehicle and multimedia device. It should be understood that a user equipment may also be an almost dedicated uplink-only device, an example of which is a camera or camcorder that loads images or video clips to a network.

[0041] In LTE (as an example), the core network 150 may be referred to as an evolved packet core (EPC), which may include a mobility management entity (MME) that may handle or assist with mobility / serving cell changes of user equipment between BSs, one or more gateways that may forward data and control signals between the BSs and a packet data network or the Internet, and other control functions or blocks.

[0042] Various example implementations may be applied to various wireless technologies, wireless networks, such as LTE, LTE-A, 5G (New Radio or NR), cmWave, and / or mmWave band networks, or any other wireless network or use case. LTE, 5G, cmWave, and mmWave band networks are provided as illustrative examples only, and various example implementations may be applied to any wireless technology / wireless network. Various example implementations may also be applied to a variety of different applications, services, or use cases, such as ultra-reliable low-latency communications (URLLC), Internet of Things (IoT), time-sensitive communications (TSC), enhanced mobile broadband (eMBB), massive machine type communications (MMTC), vehicle-to-vehicle (V2V), vehicle-to-device, etc. Each of these use cases or types of UEs may have its own set of requirements.

[0043] NR over non-terrestrial networks (NTN) is the subject of current development. The goal is to provide 5G NR services to users on Earth, for example, via low earth orbit (LEO), geostationary orbit (GEO) satellites and high altitude pseudo satellites (HAPS). Note that this can also include mobile devices on aircraft or other mobile devices on other flying objects on Earth. In addition, some developments point to narrowband Internet of Things / enhanced machine type communications (NB-IoT / E-MTC) over NTN.

[0044] NTN WI can target LEO satellites at an altitude of 500-1500km. Each LEO satellite can provide NR services on the earth through one or more satellite beams that create NR cells. Due to their low altitude, these satellites move at a speed of about 7.5km / s relative to the earth. Figure 2 An example of an NTN system 200 based on a transparent architecture is shown, where the gNB 230 is on the ground and the satellite communicates with the NTN gateway (NTN-GW) 230 via a feeder link 250. Figure 2 As shown, the NTN-GW is co-located with the gNB on the ground; this is not a requirement nor a limitation in any way. The link between the satellite and the UE 220 (the service link 240) is a 3GPP link for NR and NB-IoT / E-MTC.

[0045] One development point is to arrange for the gNB to broadcast the satellite position and its velocity vector (referenced to a specific time) as part of the serving satellite ephemeris information. This information is broadcast in the System Information Block (SIB) within the downlink broadcast channel.

[0046] NTN UE uses its GNSS position and serving satellite ephemeris information to determine how to send to the network, i.e. adjust UL timing advance (TA) and apply Doppler frequency offset pre-compensation for the serving link. Therefore, without GNSS (and without obtaining serving satellite ephemeris information in SIB), the UE cannot access the system. In addition, UE location information can be used for mobility purposes and country identification for billing and legal procedures.

[0047] In NTN, the timing advance (TA) and Doppler shift of the UE in the LEO system change in a predictable manner even when the UE is stationary due to satellite movement. Figure 3 A model 300 of satellite motion is shown in FIG. In this figure, a LEO satellite is at an elevation angle θ of the UE. The satellite is assumed to be at an altitude of 600 km in a circular orbit. The service link TA (i.e., the round-trip propagation time between the satellite and the UE) and the Doppler shift are respectively Figure 4A and Figure 4B is shown as a function of elevation angle over time.

[0048] The UE can receive and process the serving satellite ephemeris information only at predictable times, for example, a period of about 3 seconds. Therefore, when the UE is sending data to the satellite on the UL channel, the serving satellite ephemeris information may exceed about half of the time. Therefore, for the serving link, there may be some errors in the UL TA and the applied Doppler frequency offset pre-compensation.

[0049] In traditional NTN, the NTN UE uses its GNSS position and serving satellite ephemeris information to determine how to send to the network in UL timing and applied Doppler frequency offset compensation. As standard UE behavior, it is assumed that the UE uses its real position (or at least the most accurate estimate it can have based on the information provided by GNSS) to manipulate the UL timing and frequency pre-compensation in the UL.

[0050] However, there are situations where the UE may not use its true position to manipulate the UL time and frequency pre-compensation in the UL. For example, the UE may have inaccurate position information from the GNSS. This may be due to GNSS unavailability, for example, because the UE does not receive signals from a sufficient number of GNSS satellites, or due to other reasons to which the GNSS system is sensitive, such as interference, spoofing, etc. This may be due to the UE being in an indoor location. In this case, the UE will also likely apply incorrect UL time / frequency pre-compensation and may not be able to access the network. However, in the case where the UE has been able to acquire its position at an earlier point in time and has not moved too much, the available position information is still valid for UL synchronization and access.

[0051] An important reason why the UE does not use its true location is when the UE intentionally reports a false location to the network. This occurs when the user wants to avoid roaming and other charges or comply with certain regulations. This fraudulent behavior often occurs near state boundaries. In this case, the reprogrammed UE will use its true location in order to calculate and apply UL timing while reporting a false location to the network. The serving network entity (e.g., gNB) will then not be able to determine whether the UE is reporting the true location just by observing the UL timing, because from the network's perspective, the UE's UL transmissions will appear to be well synchronized. This situation 500 Figure 5 , which depicts a UE communicating with a satellite at its true location while reporting a false location to the network. Such a UE can exploit the fact that there may be some errors in the UL TA and apply Doppler frequency shift pre-compensation on the serving link to hide its intentions. Therefore, it may be difficult for a conventional NTN to detect such fraudulent behavior from the UE.

[0052] In contrast to conventional NTNs for detecting such fraudulent behavior from user equipment, the improved technique for operating the NTN is configured to compare the behavior of the measured time rate of change of the timing advance (TA) error (carrier frequency error) with the behavior of the predicted time rate of change of the timing advance error (carrier frequency error). Specifically, by analyzing the time rate of change (or change with respect to elevation angle) of the timing advance error or carrier frequency error when taking into account the frequency with which the user equipment accesses ephemeris information and comparing that behavior with the predicted behavior, significant differences in the reported position of the user equipment can be determined. This is possible because the user equipment must use its actual position in order to be able to send transmissions to the orbiting satellite.

[0053] Thus, an improved technique for operating an NTN allows for detection of a spoofed positioning report from a UE, since a spoofed position necessarily has a rate of change of the timing advance error (frequency error) that is significantly different from the predicted time rate of change of the timing advance error (frequency error). In some implementations, in response to detecting a spoofed positioning report from a UE, the NTN sends signaling configured to remove the UE from the NTN. Alternatively, in response to receiving such signaling, the UE may report a more accurate positioning, such as within a specified threshold (e.g., 5%) of the actual positioning.

[0054] It will be appreciated that the transmission time error is the error in the UE UL transmission time, which is determined by the network node by performing measurements in the UL signal as received. It will also be appreciated that the timing advance value

[0055] Fig. 6A 6 is a graph 600 showing the timing advance error in a serving link (e.g., serving link 240) as a function of elevation angle during a satellite flyby. Assume that the UE reads the ephemeris information every 3 seconds. Between consecutive readings, the UE adjusts its TA based on a linear TA approximation and using ideal information of its own position. Although the predictive satellite propagation model applied by the UE, i.e., the model used for TA prediction, is a matter of device implementation. Without loss of generality, a linear (i.e., first order polynomial) approximation model is assumed. Based on this modeling, the UE obtains the satellite velocity vector from the ephemeris information. The UE uses the ephemeris information to calculate the time rate of change of the TA.

[0056] It should be understood that Fig. 6A The curve 600 in represents the prediction error with which the TA error determined from the reported UE position values ​​is compared. More specifically, it is the time rate of change, ie the difference over time of the compared TA error values.

[0057] In some implementations, the time rate of change of TA includes the difference between the actual UL signal arrival time and the time when the signal is predicted to arrive at the network node (e.g., gNB) based on the instructions in the TA command (TAC) sent from the network to the UE. For example, if the UE were to send the UL signal on the serving link 240 exactly at the time the ephemeris information was generated, there would be no TA error. However, because there is a time delay between receiving the ephemeris information and sending the UL signal, there will be an error in TA.

[0058] In some implementations, the time rate of change of TA includes the difference between the actual UL signal arrival time and the time when the signal is predicted to arrive at the network node (e.g., gNB) based on the instructions in the TA command (TAC) sent from the network to the UE and the TA reported by the UE. For example, if the UE were to send the UL signal on the serving link 240 exactly at the time the ephemeris information was generated, there would be no TA error. However, because there is a time delay between receiving the ephemeris information and sending the UL signal, there will be an error in the TA.

[0059] In some implementations, the time rate of change of TA includes the difference between the actual UL signal arrival time and the time when the signal arrives at the network node (e.g., gNB) based on the arrival time of the pre-compensated signal updated at the UE using the most recent ephemeris information. In this case, the UE adjusts its TA based on a linear TA approximation and using information about its own position. That is, the UE assumes that the TA varies linearly with the TA calculated from the ephemeris information using a predicted satellite propagation model.

[0060] Figure 6B is a graph showing carrier frequency error in a serving link (e.g., serving link 240) as a function of elevation angle during a satellite flyby. It is assumed that the UE reads the ephemeris information every 3 seconds. Between consecutive readings, the UE adjusts its carrier frequency based on a linear carrier frequency approximation and using ideal information of its own position. In order to pre-compensate the carrier frequency while taking into account the Doppler shift on serving link 240, the UE uses a constant frequency pre-compensation value based on the most recent ephemeris update and its own position information.

[0061] It should be understood that Figure 6B The curve 650 in represents the prediction error with which the carrier frequency error determined from the reported UE position value is compared. More specifically, it is the time rate of change, ie the difference over time of the compared carrier frequency error values.

[0062] In some implementations, the time rate of change of the carrier frequency error is measured from the UL reference signal as a frequency offset relative to the ideal UL carrier frequency. The carrier frequency error can be predicted using recent ephemeris information and a predicted satellite propagation model. Due to the motion of the satellite, the change in frequency comes from the Doppler effect predicted by the model. Therefore, the error in the frequency offset due to the delay from the time the ephemeris information was generated is predicted. In this regard, a difference in the time rate of change of the carrier frequency error can indicate an erroneous UE position.

[0063] In some implementations, the time rate of change of carrier frequency error is measured from the UL reference signal as a frequency offset relative to the ideal UL carrier frequency; however, in this case, if the UE has some additional carrier frequency offset (CFO), these will appear in addition to the total frequency offset measured at the gNB. For the purpose of determining the rate of change in frequency error, this quasi-constant shift may be ignored.

[0064] Fig. 7A is a graph 700 further illustrating the timing advance error in the serving link as a function of elevation angle during a satellite flyby. Assume that the UE reads the ephemeris information every 10 seconds. Between consecutive readings, the UE adjusts the TA based on a linear interpolation between the two obtained values.

[0065] Figure 7B is a graph 750 further illustrating the timing advance error in the serving link as a function of elevation angle during a satellite flyby. Assume that the UE reads the ephemeris information every 10 seconds. Between consecutive readings, the UE adjusts the carrier frequency precompensation based on a constant value of the most recent ephemeris.

[0066] Although the 3GPP specification does not force the UE to read the System Information Block (SIB) at a certain rate, it is still the responsibility of the UE to ensure that it is sufficiently synchronized in the UL and meets the time and frequency requirements as given by RAN4. In addition, during Rel-17 NTN, a "validity time" has been specified, which defines the maximum time that the UE can assume that it is still synchronized between two consecutive SIB readings. This is to avoid situations where the UE may read the SIB infrequently and risk using outdated ephemeris information. Considering the above framework and based on Fig. 6A , 6B, 7A and 7B, it is expected that the UE will adjust its SIB reading frequency depending on the elevation angle. Assuming that the UE needs to ensure a certain level of UL time and frequency alignment as specified, the ephemeris information update rate required to achieve such alignment may be significantly higher for high elevation angles.

[0067] The measured rate of change in the time error and / or frequency error, and the update rate in the UE's UL time / frequency, is evaluated relative to a threshold that can be set by the network. In some implementations, the measured rate of change also depends on the target level of location accuracy so that this can be considered valid.

[0068] Example 1-1: Figure 88 is a flow chart illustrating a process 800 of determining whether a user equipment is providing an erroneous location to an NTN. Operation 810 includes receiving, by a network node of a non-terrestrial network, a plurality of transmissions from a user equipment in the non-terrestrial network, the plurality of transmissions carrying reported positioning data representing a reported location of the user equipment. Operation 820 includes determining, by the network node, a corresponding error of a measured uplink transmission time from a predicted uplink transmission time, the measured uplink transmission time being based on the reported location of the user equipment. Operation 830 includes performing, by the network node, a comparison between: a received time rate of change of the measured uplink transmission time and the corresponding error of the predicted uplink transmission time, and an expected time rate of change of the measured uplink transmission time and the corresponding error of the predicted uplink transmission time. Operation 840 includes sending, by the network node, response indication data to the user equipment, the response indication data representing an indication of an action to be taken by the user equipment, the indication being based on the comparison.

[0069] Example 1-2: An example implementation according to Example 1-1, wherein the uplink transmission time includes an uplink timing advance.

[0070] Example 1-3: An example implementation according to Example 1-2, wherein the comparison includes: a difference between the received time rate of change and the predicted time rate of change at corresponding moments.

[0071] Example 1-4: An example implementation according to Example 1-3, wherein the difference is the maximum difference at corresponding moments.

[0072] Example 1-5: The example implementation of example 1-3 or example 1-4, wherein the action to be taken includes remedial action in response to the difference being greater than a specified threshold, and no action is taken in response to the maximum difference being less than a specified threshold. .

[0073] Example 1-6: An example implementation according to Examples 1-2 to 1-5, wherein the time rate of change of the corresponding error between the measured uplink timing advance and the predicted uplink timing advance at that moment includes: the difference between the actual uplink transmission arrival time and the time when the expected uplink transmission arrives at the network node based on the timing advance from the non-terrestrial network.

[0074] Example 1-7: An example implementation according to Examples 1-2 to 1-6, wherein the time rate of change of the corresponding error between the measured uplink timing advance and the predicted uplink timing advance at that moment includes the difference between the actual uplink transmission arrival time and the time when the expected uplink transmission arrives at the network node based on the timing advance from the non-terrestrial network and the uplink timing advance reported by the user equipment.

[0075] Example 1-8: An example implementation according to Examples 1-2 to 1-7, wherein the time rate of change of the corresponding error between the measured uplink timing advance and the predicted uplink timing advance at that moment includes the difference between the actual uplink transmission arrival time and the time when the uplink transmission is expected to arrive at the network node based on the arrival time, which has been compensated by the user equipment based on the most recent ephemeris data from the orbiting satellite.

[0076] Example 1-9: An apparatus comprising components for performing the method of any one of Examples 1-1 to 1-8.

[0077] Example 1-10: A computer program product, comprising a non-transitory computer-readable storage medium and storing executable code, which, when executed by at least one data processing device, is configured to cause at least one data processing device to perform a method according to any one of Examples 1-1 to 1-8.

[0078] Example 2-1: Fig. 9 9 is a flow chart illustrating a process 900 of determining whether a user equipment is providing an erroneous location to an NTN. Operation 910 includes receiving, by a network node of a non-terrestrial network, a plurality of transmissions from a user equipment in the non-terrestrial network, the plurality of transmissions carrying reported positioning data representing a reported location of the user equipment. Operation 920 includes determining, by the network node, a corresponding error of a measured uplink carrier frequency from a predicted uplink carrier frequency, the measured uplink carrier frequency being based on the reported location of the user equipment. Operation 930 includes performing, by the network node, a comparison between a received time rate of change of the measured uplink carrier frequency and the corresponding error of the predicted uplink carrier frequency, and an expected time rate of change of the measured uplink carrier frequency and the corresponding error of the predicted uplink carrier frequency. Operation 940 includes sending, by the network node, response indication data to the user equipment, the response indication data representing an indication of an action to be taken by the user equipment, the indication being based on the comparison.

[0079] Example 2-2: An example implementation according to Example 2-1, wherein the comparison includes: a difference between the received time rate of change and the predicted time rate of change at corresponding moments.

[0080] Example 2-3: An example implementation according to Example 2-2, wherein the difference is the maximum difference at corresponding moments.

[0081] Example 2-4: An example implementation according to Example 2-2 or 2-3, wherein the action to be taken includes remedial action in response to the difference being greater than a specified threshold, and no action is taken in response to the maximum difference being less than a specified threshold.

[0082] Example 2-5: An example implementation according to Examples 2-1 to 2-4, wherein the time rate of change of the corresponding error between the measured uplink carrier frequency and the predicted uplink carrier frequency at that moment includes: the frequency offset relative to the ideal uplink carrier frequency at that moment.

[0083] Example 2-6: An example implementation according to Example 2-1 to Example 2-5, wherein the frequency offset relative to the ideal uplink carrier frequency at the time is manifested as an additional carrier frequency offset measured at the network node.

[0084] Example 2-7: An apparatus comprising components for performing the methods of Examples 2-1 to 2-6.

[0085] Example 2-8: A computer program product includes a non-transitory computer-readable storage medium and stores executable code, which, when executed by at least one data processing device, is configured to cause the at least one data processing device to perform the method according to Example 2-1 to Example 2-6.

[0086] Example 3-1: Fig.10 1 is a flow chart illustrating a process 1000 of determining whether a user equipment is providing an erroneous position to an NTN. Operation 1010 includes receiving, by an orbiting satellite of a non-terrestrial network, a plurality of transmissions from a user equipment in the non-terrestrial network, the plurality of transmissions carrying reported positioning data representing a reported position of the user equipment. Operation 1020 includes sending, by the orbiting satellite, a plurality of transmissions carrying the reported positioning data to a network node of the non-terrestrial network. Operation 1030 includes receiving, by the orbiting satellite, from the network node, response indication data representing an indication of an action to be taken with respect to the user equipment. Operation 1040 includes sending, by the orbiting satellite to the user equipment, action data representing an action to be taken with respect to the user equipment.

[0087] Example 3-2: An example implementation of Example 3-1, wherein the action includes removing the user equipment from the non-terrestrial network.

[0088] Example 3-3: An apparatus comprising components for performing the methods of Examples 3-1 to 3-2.

[0089] Example 3-4: A computer program product includes a non-transitory computer-readable storage medium and stores executable code, which, when executed by at least one data processing device, is configured to cause the at least one data processing device to perform the method according to Examples 3-1 to 3-2.

[0090] Example 4-1: Fig.111 is a flow chart illustrating a process 1100 of determining whether a user equipment is providing an erroneous location to an NTN. Operation 1110 includes sending, by a user equipment in a non-terrestrial network, a plurality of transmissions to a network node of the non-terrestrial network, the plurality of transmissions carrying reported positioning data representing a reported location of the user equipment, the reported location of the user equipment being different from an actual location of the user equipment at a corresponding moment in time. Operation 1120 includes receiving, by the user equipment from the network node, an instruction to remove the user equipment from the non-terrestrial network.

[0091] Example 4-2: According to the example implementation of Example 4-1, the method also includes: in response to receiving an instruction to remove the user equipment from the non-terrestrial network, sending a new reported location that differs from the actual location of the user equipment by less than a specified threshold.

[0092] Example 4-3: An apparatus comprising components for performing the methods of Examples 4-1 to 4-2.

[0093] Example 4-4: A computer program product includes a non-transitory computer-readable storage medium and stores executable code, which, when executed by at least one data processing device, is configured to cause the at least one data processing device to perform the method according to Examples 4-1 to 4-2.

[0094] List of example abbreviations

[0095]

[0096]

[0097] Fig.12 1 is a block diagram of a wireless station (e.g., AP, BS, e / gNB, NB-IoT UE, UE, or user equipment) 1200 according to an example implementation. The wireless station 1200 may include, for example, one or more RF (radio frequency) or wireless transceivers 1202A, 1202B, each of which includes a transmitter for sending signals (or data) and a receiver for receiving signals (or data). The wireless station also includes a processor or control unit / entity (controller) 1204 to execute instructions or software and control the transmission and reception of signals, and a memory 1206 for storing data and / or instructions.

[0098] The processor 1204 may also make decisions or determinations, generate time slots, subframes, packets or messages for transmission, decode received time slots, subframes, packets or messages for further processing, and other tasks or functions described herein. The processor 1204, which may be a baseband processor, may, for example, generate messages, packets, frames or other signals for transmission via the wireless transceiver 1202 (1202A or 1202B). The processor 1204 may control the transmission of signals or messages on a wireless network, and may control the reception of signals or messages, etc., via a wireless network (e.g., after being down-converted by the wireless transceiver 1202). The processor 1204 may be programmable and capable of executing software or other instructions stored in a memory or other computer medium to perform the various tasks and functions described above, such as one or more of the tasks or methods described above. The processor 1204 may be (or may include) hardware, programmable logic, a programmable processor that executes software or firmware, and / or any combination thereof, for example. For example, using other terminology, the processor 1204 and transceiver 1202 (1202A or 1202B) may be considered together as a wireless transmitter / receiver system.

[0099] In addition, refer to Fig.12 , the controller (or processor) 1208 can execute software and instructions and can provide overall control for the station 1200 and can Fig.12 Other systems not shown provide controls, such as controlling input / output devices (e.g., display, keyboard), and / or may execute software for one or more applications that may be provided on wireless station 1200, such as an email program, audio / video applications, a word processor, voice over IP applications, or other applications or software.

[0100] Additionally, a storage medium may be provided that includes stored instructions that, when executed by a controller or processor, may cause the processor 1204 or other controller or processor to perform one or more of the functions or tasks described above.

[0101] According to another example implementation, the RF or (multiple) wireless transceiver 1202A / 1202B can receive signals or data and / or transmit or send signals or data. The processor 1104 (and possibly the transceiver 1202A / 1202B) can control the RF or wireless transceiver 1202A or 1202B to receive, send, broadcast or transmit signals or data.

[0102] However, the embodiments are not limited to the systems given as examples, but those skilled in the art may apply the solution to other communication systems. Another example of a suitable communication system is the 5G concept. It is assumed that the network architecture in 5G will be very similar to Advanced LTE. 5G uses multiple-input multiple-output (MIMO) antennas, many more base stations or nodes than LTE (the so-called small cell concept), including macro sites that operate in cooperation with smaller stations, and may also employ various radio technologies to obtain better coverage and enhanced data rates.

[0103] It should be understood that future networks will most likely utilize network function virtualization (NFV), which is a network architecture concept that proposes virtualizing network node functions into "building blocks" or entities that can be operably connected or linked together to provide services. A virtualized network function (VNF) may include one or more virtual machines that use standard or general-purpose servers rather than custom hardware to run computer program code. Cloud computing or data storage may also be utilized. In radio communications, this may mean that node operations may be performed at least in part in a server, host, or node that is operably coupled to a remote radio head. It is also possible that node operations will be distributed among multiple servers, nodes, or hosts. It should also be understood that the division of labor between core network operations and base station operations may be different from LTE or even non-existent.

[0104] The implementation of the various techniques described herein can be implemented in a digital electronic circuit system, or in computer hardware, firmware, software, or in a combination thereof. The implementation can be implemented as a computer program product, that is, a computer program is tangibly embodied in an information carrier, such as a machine-readable storage device or a propagation signal, for execution or control of its operation by a data processing device, such as a programmable processor, a computer, or multiple computers. The implementation can also be provided on a computer-readable medium or a computer-readable storage medium, which can be a non-transient medium. The implementation of various techniques can also include an implementation provided via a transient signal or medium, and / or a program and / or software implementation that can be downloaded via the Internet or other (multiple) networks (wired networks and / or wireless networks). In addition, the implementation can be provided via machine type communication (MTC), and also via the Internet of Things (IoT).

[0105] A computer program may be in source code form, object code form or some intermediate form, and it may be stored in some type of carrier, distribution medium or computer readable medium, which may be any entity or device capable of carrying the program. For example, such carriers include recording media, computer memory, read-only memory, optical and / or electrical carrier signals, telecommunication signals and software distribution packages. Depending on the processing power required, a computer program may be executed in a single electronic digital computer, or it may be distributed among multiple computers.

[0106] In addition, implementations of the various techniques described herein may use a cyber-physical system (CPS) (a system of collaborative computing elements that control physical entities). CPS can enable the implementation and utilization of a large number of interconnected ICT devices (sensors, actuators, processors microcontrollers...) in physical objects at different locations. Mobile cyber-physical systems are a subcategory of cyber-physical systems in which the physical systems in question have inherent mobility. Examples of mobile physical systems include mobile robots and electronic devices transported by humans or animals. The popularity of smartphones has increased interest in the field of mobile cyber-physical systems. Therefore, various implementations of the techniques described herein may be provided via one or more of these technologies.

[0107] Computer programs such as the above-mentioned (multiple) computer programs can be written in any form of programming language, including compiled or interpreted languages, and can be deployed in any form, including as a stand-alone program or as a module, component, subroutine or other unit or part thereof suitable for use in a computing environment. The computer program can be deployed to execute on one computer or on multiple computers at one site, or deployed across multiple sites and interconnected by a communication network.

[0108] The method steps may be performed by one or more programmable processors executing a computer program or computer program portion to perform functions by operating on input data and generating output. The method steps may also be performed by a dedicated logic circuit, such as an FPGA (field programmable gate array) or an ASIC (application-specific integrated circuit), and the apparatus may be implemented as a dedicated logic circuit.

[0109] Processors suitable for executing computer programs include, for example, general and special purpose microprocessors, and any one or more processors of any type of digital computer, chip or chipset. Typically, the processor will receive instructions and data from a read-only memory or a random access memory, or both. Elements of a computer may include at least one processor for executing instructions and one or more memory devices for storing instructions and data. Typically, a computer may also include one or more mass storage devices for storing data, such as magnetic, magneto-optical or optical disks, or operatively coupled to receive data from or transfer data to, or both. Information carriers suitable for including computer program instructions and data include all forms of non-volatile memory, including, for example, semiconductor memory devices, such as EPROM, EEPROM and flash memory devices; magnetic disks, such as internal hard disks or removable disks; magneto-optical disks; and CD-ROM and DVD-ROM disks. The processor and memory may be supplemented by or incorporated into special purpose logic circuits.

[0110] To provide interaction with a user, it can be implemented on a computer having a display device (e.g., a cathode ray tube (CRT) or a liquid crystal display (LCD) monitor) for displaying information to the user and a user interface (e.g., a keyboard and a pointing device, such as a mouse or a trackball, through which the user can provide input to the computer). Other types of devices can also be used to provide interaction with the user; for example, the feedback provided to the user can be any form of sensory feedback, such as visual feedback, auditory feedback, or tactile feedback; and input from the user can be received in any form, including sound, voice, or tactile input.

[0111] The implementation may be implemented in a computing system that includes a back-end component (e.g., as a data server), or includes a middleware component (e.g., an application server), or includes a front-end component, such as a client computer with a graphical user interface or a web browser through which a user can interact with the implementation, or any combination of such back-end, middleware, or front-end components. The components may be interconnected by any form or medium of digital data communication, such as a communication network. Examples of communication networks include local area networks (LANs) and wide area networks (WANs), such as the Internet.

[0112] While certain features of the described implementations have been shown as described herein, many modifications, substitutions, changes, and equivalents will now occur to those skilled in the art. It should therefore be understood that the appended claims are intended to cover all such modifications and changes that fall within the various embodiments.

Claims

1. A device comprising: at least one processor; as well as at least one memory including computer program code; The at least one memory and the computer program code are configured to cause the apparatus to at least: receiving, by a network node of a non-terrestrial network, a plurality of transmissions from user equipment in the non-terrestrial network, the plurality of transmissions carrying reported positioning data representative of reported positions of the user equipment; determining, by the network node, a corresponding error of a measured uplink transmission time from a predicted uplink transmission time, the measured uplink transmission time being based on the reported position of the user equipment; performing, by the network node, a comparison between: a received time rate of change of the respective errors of the measured uplink transmission times and the predicted uplink transmission times and an expected time rate of change of the respective errors of the measured uplink transmission times and the predicted uplink transmission times; as well as Response indication data is sent by the network node to the user equipment, the response indication data representing an indication of an action to be taken by the user equipment, the indication being based on the comparison.

2. The apparatus of claim 1, wherein the uplink transmission comprises an uplink timing advance.

3. The apparatus of claim 2, wherein the comparing comprises: The difference between the received time rate of change and the predicted time rate of change at corresponding times.

4. A method comprising: receiving, by a network node of a non-terrestrial network, a plurality of transmissions from user equipment in the non-terrestrial network, the plurality of transmissions carrying reported positioning data representative of reported positions of the user equipment; determining, by the network node, a corresponding error of a measured uplink transmission time from a predicted uplink transmission time, the measured uplink transmission time being based on the reported position of the user equipment; performing, by the network node, a comparison between: a received time rate of change of the respective errors of the measured uplink transmission times and the predicted uplink transmission times and an expected time rate of change of the respective errors of the measured uplink transmission times and the predicted uplink transmission times; as well as Response indication data is sent by the network node to the user equipment, the response indication data representing an indication of an action to be taken by the user equipment, the indication being based on the comparison. The method of claim 4 , wherein the uplink transmission time comprises an uplink timing advance.

6. The method of claim 5, wherein the comparing comprises: The difference between the received time rate of change and the predicted time rate of change at corresponding times.

7. A device comprising: at least one processor; as well as at least one memory including computer program code; The at least one memory and the computer program code are configured to cause the apparatus to at least: receiving, by a network node of a non-terrestrial network, a plurality of transmissions from user equipment in the non-terrestrial network, the plurality of transmissions carrying reported positioning data representative of reported positions of the user equipment; determining, by the network node, a corresponding error of a measured uplink carrier frequency from a predicted uplink carrier frequency, the measured uplink carrier frequency being based on the reported position of the user equipment; performing, by the network node, a comparison between: a received time rate of change of the respective errors of the measured uplink carrier frequency and the predicted uplink carrier frequency and an expected time rate of change of the respective errors of the measured uplink carrier frequency and the predicted uplink carrier frequency; as well as Response indication data is sent by the network node to the user equipment, the response indication data representing an indication of an action to be taken by the user equipment, the indication being based on the comparison.

8. The apparatus of claim 7, wherein the comparison comprises a difference between the received time rate of change and the predicted time rate of change at corresponding moments in time.

9. The apparatus of claim 8, wherein the difference is a maximum difference at the corresponding moments.

10. A method comprising: receiving, by a network node of a non-terrestrial network, a plurality of transmissions from user equipment in the non-terrestrial network, the plurality of transmissions carrying reported positioning data representative of reported positions of the user equipment; determining, by the network node, a corresponding error of a measured uplink carrier frequency from a predicted uplink carrier frequency, the measured uplink carrier frequency being based on the reported position of the user equipment; performing, by the network node, a comparison between: a received time rate of change of the respective errors of the measured uplink carrier frequency and the predicted uplink carrier frequency and an expected time rate of change of the respective errors of the measured uplink carrier frequency and the predicted uplink carrier frequency; as well as Response indication data is sent by the network node to the user equipment, the response indication data representing an indication of an action to be taken by the user equipment, the indication being based on the comparison.

11. The method of claim 10, wherein the comparing comprises: The difference between the received time rate of change and the predicted time rate of change at corresponding times.

12. An apparatus comprising: at least one processor; as well as at least one memory including computer program code; The at least one memory and the computer program code are configured to cause the apparatus to at least: sending, by a user equipment in a non-terrestrial network to a network node of the non-terrestrial network, a plurality of transmissions carrying reported positioning data representing a reported position of the user equipment, the reported position of the user equipment differing from an actual position of the user equipment by more than a specified threshold; as well as An instruction is received by the user equipment from the network node to remove the user equipment from the non-terrestrial network.

13. A method comprising: sending, by a user equipment in a non-terrestrial network to a network node of the non-terrestrial network, a plurality of transmissions carrying reported positioning data representing a reported position of the user equipment, the reported position of the user equipment being different from an actual position of the user equipment at a corresponding moment in time; as well as An instruction is received by the user equipment from the network node to remove the user equipment from the non-terrestrial network.

14. A computer program product comprising a non-transitory computer-readable storage medium and storing executable code, which, when executed by at least one data processing device, is configured to cause the at least one data processing device to perform the method according to claim 13.

15. An apparatus comprising means for performing the method according to claim 13.

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