EP4189998A1

EP4189998A1 - Identification of an invalid reference device in device positioning

Info

Publication number: EP4189998A1
Application number: EP20947941.9A
Authority: EP
Inventors: Diomidis Michalopoulos; Dimitrios SCHOINIANAKIS; Wei Lu; Ping-Heng Kuo
Original assignee: Nokia Technologies Oy
Current assignee: Nokia Technologies Oy
Priority date: 2020-08-03
Filing date: 2020-08-03
Publication date: 2023-06-07
Also published as: AR122942A1; CN116210255A; TW202207721A; EP4189998A4; WO2022027203A1

Abstract

Example embodiments of the present disclosure relate to identification of an invalid reference device in device positioning. A method comprises receiving, at a first device and from a second device, at least one first positioning-related measurement result for positioning of at least one of a set of reference devices. The set of reference devices transmit respective reference signals for positioning a target device. The method also comprises determining at least one estimated location of the at least one reference device based on the at least one first positioning-related measurement result and a location of the second device. The method further comprises in response to a mismatch between the at least one estimated location and a set of locations of valid reference devices for the target device, identifying an invalid reference device from the at least one reference device.

Description

IDENTIFICATION OF AN INVALID REFERENCE DEVICE IN DEVICE POSITIONING

FIELD

Embodiments of the present disclosure generally relate to the field of telecommunication and in particular, to methods, devices, apparatuses and computer readable storage medium for identification of an invalid reference device in device positioning.

BACKGROUND

Many services using communications involve accurate device positioning determination. Integrity is a critical issue for some device positioning use cases, including autonomous or semi-autonomous steering of mobile objects. Example use cases include vehicle-to-everything (V2X) scenarios with outdoor coverage, where conventional global navigation satellite system (GNSS) approaches are assisted with terrestrial positioning solutions, or indoor scenarios involving automated guided vehicles (AGVs) , whose mobility process depends partially or fully on positioning by a network.
To facilitate positioning a target device, reference devices may be configured to transmit reference signals for positioning-related measurements. One or more invalid devices may act as intruders to impersonate legitimate reference devices to transmit the reference signals, which may cause distortion in location estimate of the target device. Invalid reference devices are typically communication equipment or devices, operated by malicious actors, pretending to be legitimate devices in a communication network. Protection against invalid reference devices is an important integrity management issue in device positioning.
SUMMARY
In general, example embodiments of the present disclosure provide a solution for identification of an invalid reference device in device positioning. Embodiments that do not fall under the scope of the claims, if any, are to be interpreted as examples useful for understanding various embodiments of the disclosure.
In a first aspect, there is provided a first device. The first device comprises at least one processor; and at least one memory including computer program code; where the at least one memory and the computer program code are configured to, with the at least one processor, cause the first device to receive, from a second device, at least one first positioning-related measurement result for positioning of at least one of a set of reference devices, the set of reference devices transmitting respective reference signals for positioning a target device; determine at least one estimated location of the at least one reference device based on the at least one first positioning-related measurement result and a location of the second device; and in response to a mismatch between the at least one estimated location and a set of locations of valid reference devices for the target device, identify an invalid reference device from the at least one reference device.
In a second aspect, there is provided a second device. The second device comprises at least one processor; and at least one memory including computer program code; where the at least one memory and the computer program code are configured to, with the at least one processor, cause the second device to determine at least one first positioning-related measurement result for positioning of at least one of a set of reference devices by measuring at least one reference signal from the at least one reference devices, the set of reference devices transmitting respective reference signals for positioning a target device; and transmit the at least one first positioning-related measurement result to a first device for determining at least one estimated location of the at least one reference device.
In a third aspect, there is provided a method. The method comprises receiving, at a first device and from a second device, at least one first positioning-related measurement result for positioning of at least one of a set of reference devices, the set of reference devices transmitting respective reference signals for positioning a target device; determining at least one estimated location of the at least one reference device based on the at least one first positioning-related measurement result and a location of the second device; and in response to a mismatch between the at least one estimated location and a set of locations of valid reference devices for the target device, identifying an invalid reference device from the at least one reference device.
In a fourth aspect, there is provided a method. The method comprises determining, at a second device, at least one first positioning-related measurement result for positioning of at least one of a set of reference devices by measuring at least one reference signal from the at least one reference devices, the set of reference devices transmitting respective reference signals for positioning a target device; and transmitting the at least one first positioning-related measurement result to a first device for determining at least one estimated location of the at least one reference device.
In a fifth aspect, there is provided a first apparatus. The first apparatus comprises means for receiving, from a second apparatus, at least one first positioning-related measurement result for positioning of at least one of a set of reference devices, the set of reference devices transmitting respective reference signals for positioning a target device; means for determining at least one estimated location of the at least one reference device based on the at least one first positioning-related measurement result and a location of the second apparatus; and means for, in response to a mismatch between the at least one estimated location and a set of locations of valid reference devices for the target device, identifying an invalid reference device from the at least one reference device.
In a sixth aspect, there is provided a second apparatus. The second apparatus comprises means for determining at least one first positioning-related measurement result for positioning of at least one of a set of reference devices by measuring at least one reference signal from the at least one reference devices, the set of reference devices transmitting respective reference signals for positioning a target device; and means for transmitting the at least one first positioning-related measurement result to a first apparatus for determining at least one estimated location of the at least one reference device.
In a seventh aspect, there is provided a computer readable medium. The computer readable medium comprises program instructions for causing an apparatus to perform at least the method according to the third aspect.
In an eighth aspect, there is provided a computer readable medium. The computer readable medium comprises program instructions for causing an apparatus to perform at least the method according to the fourth aspect.
It is to be understood that the summary section is not intended to identify key or essential features of embodiments of the present disclosure, nor is it intended to be used to limit the scope of the present disclosure. Other features of the present disclosure will become easily comprehensible through the following description.

BRIEF DESCRIPTION OF THE DRAWINGS

Some example embodiments will now be described with reference to the accompanying drawings, where:
Fig. 1 illustrates an example communication environment in which example embodiments of the present disclosure can be implemented;
Fig. 2 illustrates a signaling flow for identification of an invalid reference device in accordance with some example embodiments of the present disclosure;
Fig. 3 illustrates an example of positioning-related measurements for reference devices in accordance with some example embodiments of the present disclosure;
Fig. 4 illustrates a flowchart of a process of identifying an invalid reference device according to some example embodiments of the present disclosure;
Fig. 5 illustrates a signaling flow for identification of an invalid reference device in accordance with some other example embodiments of the present disclosure;
Fig. 6 illustrates a flowchart of a method implemented at a first device according to some other example embodiments of the present disclosure;
Fig. 7 illustrates a flowchart of a method implemented at a second device according to some other example embodiments of the present disclosure;
Fig. 8 illustrates a simplified block diagram of an apparatus that is suitable for implementing example embodiments of the present disclosure; and
Fig. 9 illustrates a block diagram of an example computer readable medium in accordance with some example embodiments of the present disclosure.
Throughout the drawings, the same or similar reference numerals represent the same or similar element.

DETAILED DESCRIPTION

Principle of the present disclosure will now be described with reference to some example embodiments. It is to be understood that these embodiments are described only for the purpose of illustration and help those skilled in the art to understand and implement the present disclosure, without suggesting any limitation as to the scope of the disclosure. Embodiments described herein can be implemented in various manners other than the ones described below.
In the following description and claims, unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skills in the art to which this disclosure belongs.
References in the present disclosure to “one embodiment, ” “an embodiment, ” “an example embodiment, ” and the like indicate that the embodiment described may include a particular feature, structure, or characteristic, but it is not necessary that every embodiment includes the particular feature, structure, or characteristic. Moreover, such phrases are not necessarily referring to the same embodiment. Further, when a particular feature, structure, or characteristic is described in connection with an embodiment, it is submitted that it is within the knowledge of one skilled in the art to affect such feature, structure, or characteristic in connection with other embodiments whether or not explicitly described.
It shall be understood that although the terms “first” and “second” etc. may be used herein to describe various elements, these elements should not be limited by these terms. These terms are only used to distinguish one element from another. For example, a first element could be termed a second element, and similarly, a second element could be termed a first element, without departing from the scope of example embodiments. As used herein, the term “and/or” includes any and all combinations of one or more of the listed terms.
The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of example embodiments. As used herein, the singular forms “a” , “an” and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms “comprises” , “comprising” , “has” , “having” , “includes” and/or “including” , when used herein, specify the presence of stated features, elements, and/or components etc., but do not preclude the presence or addition of one or more other features, elements, components and/or combinations thereof.
As used in this application, the term “circuitry” may refer to one or more or all of the following:
(a) hardware-only circuit implementations (such as implementations in only analog and/or digital circuitry) and
(b) combinations of hardware circuits and software, such as (as applicable) :
(i) a combination of analog and/or digital hardware circuit (s) with software/firmware and
(ii) any portions of hardware processor (s) with software (including digital signal processor (s) ) , software, and memory (ies) that work together to cause an apparatus, such as a mobile phone or server, to perform various functions) and
(c) hardware circuit (s) and or processor (s) , such as a microprocessor (s) or a portion of a microprocessor (s) , that requires software (e.g., firmware) for operation, but the software may not be present when it is not needed for operation.
This definition of circuitry applies to all uses of this term in this application, including in any claims. As a further example, as used in this application, the term circuitry also covers an implementation of merely a hardware circuit or processor (or multiple processors) or portion of a hardware circuit or processor and its (or their) accompanying software and/or firmware. The term circuitry also covers, for example and if applicable to the particular claim element, a baseband integrated circuit or processor integrated circuit for a mobile device or a similar integrated circuit in server, a cellular network device, or other computing or network device.
As used herein, the term “communication network” refers to a network following any suitable communication standards, such as New Radio (NR) , Long Term Evolution (LTE) , LTE-Advanced (LTE-A) , Wideband Code Division Multiple Access (WCDMA) , High-Speed Packet Access (HSPA) , Narrow Band Internet of Things (NB-IoT) and so on. Furthermore, the communications between a terminal device and a network device in the communication network may be performed according to any suitable generation communication protocols, including, but not limited to, the first generation (1G) , the second generation (2G) , 2.5G, 2.75G, the third generation (3G) , the fourth generation (4G) , 4.5G, the fifth generation (5G) communication protocols, and/or any other protocols either currently known or to be developed in the future. Embodiments of the present disclosure may be applied in various communication systems. Given the rapid development in communications, there will of course also be future type communication technologies and systems with which the present disclosure may be embodied. It should not be seen as limiting the scope of the present disclosure to only the aforementioned system.
As used herein, the term “network device” refers to a node in a communication network via which a terminal device accesses the network and receives services therefrom. The network device may refer to a base station (BS) or an access point (AP) , for example, a node B (NodeB or NB) , an evolved NodeB (eNodeB or eNB) , a NR NB (also referred to as a gNB) , a Remote Radio Unit (RRU) , a radio header (RH) , a remote radio head (RRH) , a relay, an Integrated Access and Backhaul (IAB) node, a low power node such as a femto, a pico, a non-terrestrial network (NTN) or non-ground network device such as a satellite network device, a low earth orbit (LEO) satellite and a geosynchronous earth orbit (GEO) satellite, an aircraft network device, and so forth, depending on the applied terminology and technology.
The term “terminal device” refers to any end device that may be capable of communication. By way of example rather than limitation, a terminal device may also be referred to as a communication device, user equipment (UE) , a Secure User Plane Location (SUPL) Enabled Terminal (SET) , a Subscriber Station (SS) , a Portable Subscriber Station, a Mobile Station (MS) , or an Access Terminal (AT) . The terminal device may include, but not limited to, a mobile phone, a cellular phone, a smart phone, voice over IP (VoIP) phones, wireless local loop phones, a tablet, a wearable terminal device, a personal digital assistant (PDA) , portable computers, desktop computer, image capture terminal devices such as digital cameras, gaming terminal devices, music storage and playback appliances, vehicle-mounted wireless terminal devices, wireless endpoints, mobile stations, laptop-embedded equipment (LEE) , laptop-mounted equipment (LME) , USB dongles, smart devices, wireless customer-premises equipment (CPE) , an Internet of Things (loT) device, a watch or other wearable, a head-mounted display (HMD) , a vehicle, a drone, a medical device and applications (e.g., remote surgery) , an industrial device and applications (e.g., a robot and/or other wireless devices operating in an industrial and/or an automated processing chain contexts) , a consumer electronics device, a device operating on commercial and/or industrial wireless networks, and the like. In the following description, the terms “terminal device” , “communication device” , “terminal” , “user equipment” and “UE” may be used interchangeably.
As used herein, the term “resource, ” “transmission resource, ” “resource block, ” “physical resource block” (PRB) , “uplink resource, ” or “downlink resource” may refer to any resource for performing a communication, for example, a communication between a terminal device and a network device, such as a resource in time domain, a resource in frequency domain, a resource in space domain, a resource in code domain, or any other resource enabling a communication, and the like. In the following, a resource in both frequency domain and time domain will be used as an example of a transmission resource for describing some example embodiments of the present disclosure. It is noted that example embodiments of the present disclosure are equally applicable to other resources in other domains.
Example Environment
Fig. 1 shows an example communication environment 100 in which example embodiments of the present disclosure can be implemented. The communication environment 100 includes a first device 110, a set of reference devices, including reference devices 120-1, 120-2, 120-3, 120-4, and 120-5, and a target device 130. For the purpose of discussion, the set of reference devices 120-1, 120-2, 120-3, 120-4, and 120-5 are collectively or individually referred to as reference devices 120.
In the example environment 100, the target device 130 is a device that is being positioned. In some example embodiments, the target device 130 may comprise a terminal device. In the shown example, the target device 130 is illustrated as a robot in an IoT scenario. However, it would be appreciated that the target device 130 may comprise any other types of terminal device.
The reference devices 120 may comprise physical entities that provide signals to be detected and measured by the target device 130 in order to obtain the location of the target device 130. The signals transmitted by the reference signals 120 for positioning the target device 130 may comprise reference signals such as positioning reference signals (PRSs) or beacon signals. The reference devices 120 may also be referred to as reference sources or transmission-reception points (TRPs) . In some example embodiments, the reference devices 120 may comprise network devices in a radio access network (RAN) . For example, the reference devices 120 may comprise a network device serving the target device 130, for example, a network device to which the target device 130 is connected. In some examples, the reference devices 120 may comprise one or more neighbor network devices of the serving network device. Alternatively, or in addition to network devices in the RAN, the reference devices 120 may comprise access points (APs) in a wireless access local network (WLAN) , devices complying with other communication protocols, such as devices, and/or the like.
The first device 110 may comprise a server and/or any other computing device configured to manage positioning for the target device 130 and/or provide data (e.g., “assistance data” ) to the target device 130 to facilitate the location determination. In such case, the first device 110 may be referred to as a location server. In some example embodiments, the first device 110 may include a core network (CN) entity which is configured to support location management of terminal devices. For example, the first device 110 may comprise a Location Management Function (LMF) that supports location of the target device 130 using a control plane (CP) location solution for 5G or NR wireless access by the target device 130. In other examples, the first device 110 may comprise a Discovered SLP (D-SLP) or an Emergency SLP (E-SLP) . The first device 110 may also comprise an Enhanced Serving Mobile Location Center (E-SMLC) that supports location of UE 105 using a control plane (CP) location solution for LTE access by the target device 130.
The positioning procedure for the target device 130 may include a target device (e.g., UE) based procedure or a target device (e.g., UE) assisted procedure. In the target device based procedure, the target device 130 performs measurements on the reference signals transmitted from a plurality of reference devices 120 and estimates its location based on results of the measurements. The measurements may also refer to positioning-related measurements or measurements performed for positioning purposes. The results of the measurements may thus be referred to as positioning-related measurement results. In the target device assisted procedure, the target device 130 reports the positioning-related measurement results to the first device 110, for example, via non-access stratum (NAS) . The first device 110 then estimates the location of the target device 130 based on the positioning-related measurement results. The first device 110 may provide the estimated location to the target device 130 and/or to any other entity requesting the location of the target device 130.
It is to be understood that the numbers of devices are only for the purpose of illustration without suggesting any limitations. The communication environment 100 may include any suitable number of first devices, reference devices, and target devices adapted for implementing example embodiments of the present disclosure.
Communications in the communication environment 100 may be implemented according to any proper communication protocol (s) , comprising, but not limited to, cellular communication protocols of the first generation (1G) , the second generation (2G) , the third generation (3G) , the fourth generation (4G) and the fifth generation (5G) and on the like, wireless local network communication protocols such as Institute for Electrical and Electronics Engineers (IEEE) 802.11 and the like, and/or any other protocols currently known or to be developed in the future. Moreover, the communication may utilize any proper wireless communication technology, comprising but not limited to: Code Division Multiple Access (CDMA) , Frequency Division Multiple Access (FDMA) , Time Division Multiple Access (TDMA) , Frequency Division Duplex (FDD) , Time Division Duplex (TDD) , Multiple-Input Multiple-Output (MIMO) , Orthogonal Frequency Division Multiple (OFDM) , Discrete Fourier Transform spread OFDM (DFT-s-OFDM) and/or any other technologies currently known or to be developed in the future.
The accuracy requirement for device positioning is rising in order to support critical service requirements in many applications. For example, a detailed list of 5G positioning requirements has been provided in Table 7.3.2.2-1 of 3GPP specification TS 22.261, which is copied below.
Table 7.3.2.2-1 Performance requirements for Horizontal and Vertical positioning service levels
As can be seen, for some positioning service levels, the level of positioning accuracy as well as that of service availability reaches challenging numbers (e.g., accuracy of 0.3m with availability of 99.9%) , implying that integrity as an end-to-end service should cover multiple domains such that the anticipated use cases are covered.
A major issue associated with device positioning is that of security, as part of the overall integrity requirement in a communication network. In particular, the location estimated in some critical applications needs to correspond very closely to the ground-truth location; otherwise the integrity levels cannot be reached and thus the positioning service will fail to meet its requirements.
The term “invalid reference device” is in general to denote a device that impersonates a genuine reference device. The “invalid reference device” may also be referred to as an “illegitimate reference device, ” a “fake reference device, ” or “an invalid reference device, ” and those terms are used interchangeably herein. Contrary to the invalid reference device, a genuine reference device is also referred to as a “valid reference device, ” a “legitimate reference device, ” or “atrue reference device, ” and those terms are used interchangeably herein.
An invalid reference device is maliciously used by attackers for tampering with positioning data (among others) and causing malfunctions. More specifically, some positioning procedures require measuring reference signals that are transmitted by known reference devices at the target device such that the location of the target device can be estimated on the basis of positioning-related measurement results. If one or more reference devices are invalid reference devices which are not registered to the network and transmit reference signals that are measured by the target device, the estimated location of the target device would be distorted. For example, in the communication environment 100 of Fig. 1, in case of an invalid reference device (such as the reference device 120-5) , the first device 110 may not be able to distinguish between legitimate and non-legitimate positioning-related measurement results and may use all the received results to estimate the location of the target device 130. Depending on the associated use case, the distorted location of the target device 130 may cause critical problems.
Generally, the reference signals transmitted for the purpose of positioning are non-encrypted beacons because there is no need for the target device to establish secure connections with the reference devices for receiving the reference signals. Thus, the reference signals may be easily imitated, replayed, or tampered by malicious attackers. As a result, an invalid reference device can forge the reference signal from an unknown location which is not registered in the network. In another scenario, the invalid reference device may be able to replay the reference signal from a legitimate reference device, which is, however, not among the valid reference devices for the target device. The replayed reference signal may have potentially the same pattern of the reference signal used by a neighbour reference device. In such attacking scenarios, the target device may derive a positioning-related measurement result by measuring the reference signal which did not originate from the location of the legitimate neighbour reference device that is registered at the network. Hence, on the basis of such an “iilegitimate” positioning-related measurement result, the location of the target device may be distorted, e.g., it does not correspond to the ground-truth location.
Some positioning procedures, such as a network assisted positioning procedure and a procedure of obtaining non-target device associated network assistance data, may not require the target device to take part in the position measuring and reporting. It is the network devices that obtain and report the positioning measurements for the target device that is being positioned. As the network devices have already established secure connection with the core network entity (such as the Access and Mobility Management Function –AMF) before obtaining and reporting the positioning measurements, an invalid reference device may not have the opportunity to intrude for launching any attack.
However, in the target device (e.g., UE) based positioning procedure or the target device (e.g., UE) assisted positioning procedure as described above, the target device needs to perform positioning-related measurements and/or location estimation based on reference signals received from a set of reference devices. To ensure positioning integrity for a target device, it would be desirable to identify an invalid reference device (s) from a set of reference devices that transmit reference signals for positioning the target device.
Basic working principle
In accordance with some example embodiments of the present disclosure, there is provided a solution for identification of an invalid reference device (s) in device positioning. In this solution, a first device receives, from a second device, at least one first positioning-related measurement result for at least one of a set of reference devices. The second device, for example, may comprise a target device that is being positioned or any trustable device whose location is known by the first device. The first device determines at least one estimated location of the at least one reference device based on the at least one first positioning-related measurement result and a location of the second device. The first device then compares the at least one estimated location with a set of locations of valid reference devices for the target device. If a mismatch is found between the at least one estimated location and the set of locations of valid reference devices, the first device determines that the at least one reference device comprises one or more invalid reference devices. The first device can identify the invalid reference device (s) from the at least one reference device whose estimated location is obtained.
Through this solution, by instructing a second device to report a positioning-related measurement result (s) used for determining an estimated location (s) of a reference device (s) , the first device can verify whether there exists an invalid reference device (s) . This solution can support accurate detection of the invalid reference device (s) , without introducing significant overheads between the devices or changes in existing positioning procedures. In addition, there is no need for heavyweight cryptographic solutions to hide positioning-related information in the solution of the present disclosure.
The accurate detection of the invalid reference device (s) can ensure accurate location determination of the target device, for example, by excluding a positioning-related measurement result (s) obtained by measuring a reference signal (s) from the invalid reference device (s) .
Example embodiments of the present disclosure will be described in detail below with reference to the accompanying drawings. As mentioned, the second device, which assists the first device in the identification of the invalid reference device (s) , can be either the target device or any other trustable device with its location known by the first device. In the following, depending on the choice of the second device, the identification of the invalid reference device (s) may involve different devices, example embodiments of which will be described with reference to Fig. 2 and Fig. 5, respectively.
Target device-assisted identification of invalid reference device (s)
Reference is first made to Fig. 2, which shows a signaling flow 200 for identification of an invalid reference device in accordance with some example embodiments of the present disclosure. For the purpose of discussion, the signaling flow 200 will be described with reference to Fig. 1. The signaling flow 200 involves the first device 110, a set of reference devices 120, and the target device 130 in Fig. 1. In the example embodiments of Fig. 2, the target device 130 acts as a second device to provide assistance information for the first device 110 to check whether an invalid reference device (s) are included in the set of reference devices 120.
As illustrated, the set of reference devices 120 transmits 205 respective reference signals for the purpose of positioning the target device 130. The set of reference devices 120, as discussed above, may comprise network devices in RAN, APs in WLAN, and/or other devices that are capable of transmitting reference signals for the purpose of positioning.
In example embodiments of the present disclosure, the target device 130 determines 210 at least one first positioning-related measurement result for positioning of at least one of the set of reference devices 120 by measuring at least one reference signal from the at least one reference device 120.
In some example embodiments, the target device 130 may be configured by the first device 110 to report the first positioning-related measurement result (s) for the at least one reference device 120. The first device 110 may transmit 212 measurement configuration information to the target device 130. The measurement configuration information is used to configure the target device 130 to report a respective first positioning-related measurement result for at least one reference device 120. The at least one reference device 120 may be the one (s) that are considered as a potential invalid reference device. In an example embodiment, the first device 110 may configure the target device 130, by means of the measurement configuration information, to report a first positioning-related measurement result for each reference device 120 from which a reference signal is transmitted and measured by the target device 130.
The measurement configuration information may be provided as a physical security configuration to the target device 130. Upon reception 214 of the measurement configuration information, the target device 130 may determine the first positioning-related measurement result (s) for the configured reference device (s) accordingly. In some example embodiments, the target device 130 may be specified or preconfigured to report the first positioning-related measurement result associated with each reference device 120 from which the reference signal is detected.
A first positioning-related measurement result associated with a corresponding reference device 120 includes measurement information that can be used to determine a location of the reference device 120. The first positioning-related measurement result may comprise various measurement information to enable positioning of the reference device 120. Specifically, the first positioning-related measurement result may comprise a timing measurement, an angle-related measurement, and/or, a received power-related measurement performed on the reference signal transmitted from the corresponding reference device 120. The timing measurement may allow for distance estimation between the target device 130 and the corresponding reference device 120. In some example embodiments, the timing measurement may include a measurement of timing advance (TA) of the corresponding reference device 120.
The angle-related measurement may allow for angle estimation between the target device 130 and the corresponding reference device 120. In some example embodiments, the angle-related measurement may include measurement information indicating an angle of departure (AoD) at the corresponding reference device 120. The AoD may be measured as AoD of the reference signal transmitted from the corresponding reference device 120.
As shown in Fig. 3, it is assumed that the target device 130 is configured to report first positioning-related measurement results for positioning of the reference devices 120-1 to 120-5. The target device 130 may detect reference signals from the reference devices 120-1 to 120-5 using beams 311 to 315 and measure the received signal powers of the reference signals. The target device 130 may then determine respective angle-related measurements of AoD (represented as θ ₁, θ ₂, θ ₃, θ ₄, and θ ₅) at the reference devices 120-1 to 120-5.
As an alternative, or in addition, the angle-related measurement may include measurement information indicating a relative angle between a direction of arrival at the target device 130 from the corresponding reference device 120 and a direction of arrival at the target device 130 from a given reference device 120. The direction of arrival at the target device 130 from a reference device 120 may be determined by measuring the direction of arrival of the reference signal transmitted from the reference device 120. That is, since the orientation of the target device 130 is unknown, the target device 130 may measure the angle at which it sees the corresponding reference device 120 relative to a reference angle at which it sees the certain reference device. The relative angle may be considered as a relative angle. The certain reference device 120 may be a serving device among the set of reference devices 120 for the target device 130 or any other device that is used as a measurement reference for determining the relative angle.
To better illustrate the measurements of the relative angles, as illustrated in Fig. 3, it is assumed that the reference device 120-3 is used as a measurement reference for measuring the relative angles for other reference devices. A relative angle 321 between a direction of arrival from the reference device 120-1 and a direction of arrival from the reference device 120-3 is measured at the target device 130. Similarly, the target device 130 can measure a relative angle 322 between directions of arrival from the reference device 120-2 and the reference device 120-3, a relative angle 323 between directions of arrival from the reference device 120-4 and the reference device 120-3, and a relative angle 324 between directions of arrival from the reference device 120-5 and the reference device 120-3.
For a reference device 120, the received power-related measurement may comprise a received power of the reference signal measured from this reference device 120. In some example embodiments, the received power-related measurement indicates a reference signal received power (RSRP) , a reference signal received quality (RSRQ) , and/or any other indicator for received energy of the reference signal. In some example embodiments, the target device 130 may perform a beam-specific measurement of the received power for each of receiving beams.
Some example measurements have been provided to be used for estimating the locations of the reference devices 120. It would be appreciated that various other aspects of measurements performed on the reference signals transmitted from the reference devices 120 may also be determined and included in the first positioning-related measurement results as long as such measurements can facilitate positioning of the reference devices 120.
In addition to the first positioning-related measurement result (s) , the target device 130 further determines a set of second positioning-related measurement results for positioning of the target device 130 by measuring the respective reference signals transmitted from the set of reference devices 120. Each second positioning-related measurement result is associated with one of the set of reference devices 120, being obtained by measuring the reference signal transmitted by this corresponding reference device 120.
The set of second positioning-related measurement results include measurement information that can be used to determine a location of the target device 130. As an example, the target device 130 may measure downlink (DL) time reference of arrivals (DL-TDoA) of the reference signals from the corresponding reference device 120 and another reference device 120 (which acts as a measurement reference) . Accordingly, a second positioning-related measurement result associated with a corresponding reference device 120 may include measurement information indicating Reference Signal Time Difference (RSTD) . RSTD is a relative timing difference between the corresponding reference device 120 and the other reference device 120 acting as a measurement reference.
It would be appreciated that each second positioning-related measurement result may alternatively or additionally include other measurement information that can be used for positioning of the target device 130, depending on the location estimation method applied by the first device 110.
Reference is still made to Fig. 2, the target device 130 transmits 215, to the first device 110, the at least one first positioning-related measurement result for positioning of the at least one reference device 120. Additionally, the target device 130 transmits, to the first device 110, the set of second positioning-related measurement results for positioning of the target device 130. The first positioning-related measurement result (s) may be transmitted together with or separately from the set of second positioning-related measurement results.
The first device 110 receives 220 the at least one first positioning-related measurement result as well as the set of second positioning-related measurement results. In order to check whether any invalid reference device intrudes into the positioning-related measurements of the target device 130, the first device 110 determines 225 at least one estimated location of the at least one reference device 120 based on the at least one first positioning-related measurement result and a location of the target device 130.
As the ground-truth location of the target device 130 is unknown, the first device 110 may determine an estimated location of the target device 130 based on the set of second positioning-related measurement results and use the estimate location of the target device 130 to determine the estimated location of the at least one reference device 120. It is known that there are various available positioning approaches for location estimation of the target device 130. The first device 110 may apply any suitable one of the positioning approaches, and the scope of the present disclosure is not limited in this regard.
Given the estimated location of the target device 130, for each reference device 120 with a first positioning-related measurement result reported, the first device 110 may determine an estimated location of the reference device 120 based on the corresponding first positioning-related measurement result and the estimated location of the target device 130.
In some example embodiments, the first device 110 may determine an estimated distance between the reference device 120 and the target device 130 based on the timing measurement (such as the measurement of TA) and/or the received power-related measurement included in the associated first positioning-related measurement result and the estimated location of the target device 130. The first device 110 may further determine an estimated angle of a direction of arrival at the reference device 120 from the target device 130 based on the at least one angle-related measurement obtained from the target device 130, such as the measurement information indicating the AoD (s) at the reference device (s) 120 or the relative angle of directions of arrival between two reference devices 120 at the target device 130. The first device 110 may then determine the estimated location of the corresponding reference device 120 based on the estimated distance, the estimated angle, and the estimated location of the target device 130.
It would be appreciated that depending on the first positioning-related measurement result (s) , the first device 110 may apply other approaches to perform the location estimation of the reference device (s) 120. The scope of the present disclosure is not limited herein.
With the at least one estimated location of the at least one reference device 120 determined, the first device 110 compares the at least one estimated location of the reference device (s) 120 with a set of locations of valid reference devices 120 for the target device 130. The valid reference devices 120 may be those that are registered in a tracking area of the target device 130. In some example embodiments, the set of locations of valid reference devices 120 may be provided by the AMF to the first device 110. In some example embodiments, the set of locations of valid reference devices 120 may be represented as a range of the tracking area of the target device 130.
Depending on the result of the comparison, if the first device 110 detects a mismatch between the at least one estimated location of the reference device (s) 120 and the set of locations of valid reference devices, the first device 110 can determine that there is at least one invalid reference device transmitting the reference signal measured by the target device 130. Accordingly, the first device 110 identifies 230 an invalid reference device from the at least one reference device 120. In some example embodiments, the mismatch may be detected if one or more estimated locations are found to be far from the set of locations of valid reference devices, e.g., far from the tracking area of the target device 130.
In some example embodiments, as an invalid reference device may be capable of duplicating or replaying the reference signal from a valid reference device, the first device 110 may not be able to distinguish, among the set of second positioning-related measurement results, legitimate and illegitimate measurements performed with respect to the reference devices. Thus, the first device 110 may treat all the reference devices 120 as untreatable reference devices and may need to verify each of the reference devices 120. Thus, the target device 130 may be requested to report first positioning-related measurement results for each of the set of reference devices 120 from which the reference signals for positioning are measured. In some example embodiments, if the first device 110 can be sure in some way that one or more of the set of reference devices 120 not being impersonated by an invalid reference device, the first positioning-related measurement result may not be required from the target device 130. In this case, the first device 110 may skip the verification of the valid reference device (s) 120, e.g., by not requiring the target device 130 to report the first positioning-related measurement result.
In some example embodiments, if only one reference device 120 needs to be verified, the mismatch between the estimated location of this reference device 120 and the set of locations of valid reference devices may indicate that this reference device 120 is an invalid reference device. In some cases, if the first device 110 needs to verify two or more reference devices 120, the first device 110 may not specifically inter which reference device 120 is an invalid one and which is not based on only the mismatch between the estimated locations and the set of locations of valid reference devices. To specifically localize the fake reference device (s) among the two or more reference devices 120, the first device 110 may apply a method of exclusion to check whether the estimated location (s) of the remaining reference device (s) 120 all match the location of valid reference devices if one or more reference devices 120 are excluded.
In particular, each time when one or more reference devices 120 are excluded, the first device 110 discards the second positioning-related measurement results associated with the excluded reference device (s) 120 and uses the remaining second positioning-related measurement results to update the estimated location of the target device 130. The first device 110 may determine updated estimate locations of the remaining reference device (s) 120 based on the updated estimated location of the target device 130 and the first positioning-related measurement result (s) for the remaining reference device (s) 120.
The updated estimate location (s) of the remaining reference device (s) 120 are then compared the set of locations of valid reference devices. If all the updated estimate location (s) matching the set of locations of valid reference devices, for example, if all the updated estimate location (s) are within the tracking area of the target device 130, it means that the estimated location of the target device 130 is legitimate and thus the remaining reference device (s) 120 are all legitimate. Accordingly, the one or more excluded reference devices 120 may be determined as invalid reference devices.
The first device 110 may perform an iterative process to verify all possible combinations of the reference devices 120, where a number of reference devices are excluded from the combination in each round of iteration. Fig. 4 illustrates such an iterative process 400 of identifying an invalid reference device according to some example embodiments of the present disclosure.
At block 405, the first device 110 sets a number of reference devices to be excluded (represented as N) to be one ( “1” ) . At block 410, the first device 110 excludes the number of N reference devices from a plurality of reference devices 120 to be verified. By excluding different N reference devices, the first device 110 obtains M sets of remaining reference devices 120, each set comprising a different combination of the reference devices 120.
As an example, it is assumed that the first device 110 needs to check whether each of the five reference devices 120-1 to 120-5 in the example of Fig. 1 is an invalid reference device or not. If one reference device (N=1) is to be excluded from the five reference devices, the first device 110 may obtain five sets of remaining reference devices with one different reference device excluded from a set. The five sets of remaining reference devices may be represented as {120-1, 120-2, 120-3, 120-4} , {120-1, 120-2, 120-3, 120-5} , {120-1, 120-2, 120-4, 120-5} , {120-1, 120-3, 120-4, 120-5} , and {120-2, 120-3, 120-4, 120-5} .
The first device 110 performs M times of iteration to determine whether the estimated locations of the remaining reference devices 120 in the M sets match with the set of locations of valid reference devices. Specifically, the M sets of remaining reference devices may be indexed from 1 to M. At block 415, the first device 110 sets an index i for a set of remaining reference devices 120 to be one ( “1” ) . At block 420, the first device 110 updates the estimated location of the target device 130 based on the second positioning-related measurement results associated with the i-th set of remaining reference devices 120. The second positioning-related measurement result (s) associated with the reference device (s) excluded from the i-th set may be discarded from the location estimation of the target device 130.
At block 425, the first device 110 updates the estimated locations of the i-th set of remaining reference devices 120 based on the updated estimated location of the target device 130 and the first positioning-related measurement results reported by the target device 130 for the i-th set of remaining reference devices. The first device 110 may re-compute the estimated location of each reference device 120 in tie i-th set. The location estimation of the reference device 120 may be performed in a same way as described above.
At block 430, the first devices 110 determines whether the updated estimated locations of the i-th set of remaining reference devices 120 all match the set of locations of valid reference devices. If the updated estimated locations match the set of locations of valid reference devices, the process 400 proceeds to block 435. At block 435, the first device 110 identifies the N excluded reference devices from the i-th set of remaining reference devices 120 as invalid reference devices. In the above example with reference to Fig, 1, if the updated estimated locations determined for the set of reference devices {120-1, 120-2, 120-3, 120-4} match the set of locations of valid reference devices, the first device 110 identifies that the reference device 120-5 missing from this set is an invalid reference device.
If a mismatch between the updated estimated locations and the set of locations of valid reference devices is detected, the process 400 proceeds to block 440, where the first device 110 sets the index i to be incremented by one (i.e., i=i+1) in order to verify the next set of remaining reference devices 120. At block 445, the first device 110 determines whether the M sets of remaining reference devices 120 are all verified by checking whether i>M. If i≤M, the process 400 returns to block 420 to verify the next set of remaining reference devices 120. If i>M, the first device 110 fails to specifically infer the invalid reference devices by excluding only the N reference devices because the number of invalid reference devices may be larger than N. Thus, the process 400 proceeds to block 450 where the first device 110 sets N to be incremented by one (i.e., N =N+1) in order to exclude a larger number of reference devices from the plurality of reference devices to be verified. The process 400 repeats from blocks 410.
By performing one or more rounds of iterations in the process 400, the first device 110 can identify N (where N may be equal to or larger than one) invalid reference devices. It would be appreciated that the iterative process 400 shown in Fig. 4 is provided for the purpose of illustration only. There may be many variants based on the iterative process 400. For example, more than one reference device may be excluded in one or more time of iteration. The scope of the present disclosure is not limited in this regard.
In some example embodiments, during the verification of the reference devices 120, if the updated estimated locations of a set of remaining reference devices 120 match the set of locations of valid reference devices, the updated estimated location of the target device 130 obtained in the current round of iteration may be determined as a valid or legitimate location of the target device 130. The first device 110 may transmit the determined valid location of the target device 130 to the target device 130 or to any entity requesting the location of the target device 130. The accuracy of the location of the target device 130 can be ensured as it is determined based on positioning-related measurement results associated with legitimate reference devices 120.
After the first device 110 has identified one or more invalid reference devices 120, in some example embodiments, the first device 110 may notify the target device 130 of the invalid reference device (s) . Referring back to Fig. 2, in some cases, the first device 110 transmits 235 an indication to the target device 130 to indicate the invalid reference device (s) 120 from which the target device 130 detected the reference signal (s) . By receiving 240 the indication from the first device 110, the target device 130 can determine which reference device (s) is illegitimate or which reference signal (s) is originated from the invalid reference device (s) .
In some example embodiments, the first device 110 may update the assistance data with an assistance data update message to indicate the invalid reference device (s) . This assistance data update message may contain updated information on reference signals to be measured and reported, where the reference signals may be marked as legitimate or non-legitimate based on the identification of the invalid reference device (s) . For example, the assistance data update message may include updated information on the OTDOANeighbourCellInfoList information element (IE) , where the invalid reference device (s) is flagged.
In some example embodiments, if the location estimate of the target device 130 is performed locally, the target device 130 may discard the current second positioning-related measurement results from being used for determining its location. In future location estimation, the target device 130 may also ignore the reference signal (s) transmitted from the invalid reference device (s) , ensuring accurate location estimation. In some example embodiments, if the location estimate of the target device 130 is performed remotely, for example, by the first device 110, the target device 130 may not perform and report the positioning-related measurements from the invalid reference device (s) .
As the invalid reference device (s) has been identified, in some example embodiments, the first device 110 may further determine to cause a mitigation action to be performed against the invalid reference device (s) in order to remove potential security issues in the communication network. Specifically, the first device 110 may notify a network operator of the presence of the invalid reference device (s) . The network operator may thus inform a law-enforcement entity in an area where the invalid reference device (s) is likely to be localized.
Trustable device-assisted identification of invalid reference device (s)
In some example embodiments, as mentioned above, instead of relying on first positioning-related measurement result (s) reported from the target device 130, the first device 110 may alternatively instruct a trustable device to measure and report the first positioning-related measurement result (s) for positioning the reference device (s) 120 to be verified. In some example embodiments, the assistance from the trustable device may be needed if the location of the target device 130 is not available at the first device 110, for example, if the target device 130 does not report the first positioning-related measurement results to the first device 120. In some other cases, the target device 130 itself may be a malicious device that may not provide true information. Thus, the first device 110 may decide not using the reporting from the target device 130 to identify the invalid reference device (s) .
Fig. 5 illustrates a signaling flow 500 for identification of an invalid reference device in accordance with some example embodiments where a trustable device is involved. The signaling flow 500 involves the first device 110, a set of reference devices 120, and the target device 130 in Fig. 1. The signaling flow 500 additionally involves a trustable device 502 which acts as a second device to assist the first device 110 in estimating the location (s) of the reference device (s) 120 to be verified.
The trustable device 502 may be any device registered in the communication network which is trusted by the first device 110. The valid location of the trustable device 502 is known at the first device 110. In some example embodiments, the first device 110 may be configured with one or more trustable devices and their valid locations, for example, during the network deployment phase. In some example embodiments, the one or more trustable devices and their valid locations may be provided to the first device 110 by a CN entity during operation. The trustable device 502 may be one of the reference devices 120 which transmit reference devices for positioning the target device 130. In some other example embodiments, the trustable device 502 may comprise any other network device or registered device in the communication network which is capable of measuring reference signals from the reference devices 120.
The signaling flow 500 is similar to the signaling flow 200 of Fig. 2 but the role of the target device 130 in the signaling flow 200 is replaced by the trustable device 502. Specifically, as illustrated, the set of reference devices 120 transmits 505 respective reference signals for the purpose of positioning the target device 130. The trustable device 502 determines 510 at least one first positioning-related measurement result for positioning of at least one of the set of reference devices 120 by measuring at least one reference signal from the at least one reference device 120. The first positioning-related measurement result for each reference device 120 may be similar to the one as discussed above.
The trustable device 502 may be configured by the first device 110 to report the first positioning-related measurement result (s) for the at least one reference device 120. The first device 110 may transmit 512 measurement configuration information to the trustable device 502, to instruct the trustable device 502 to report the first positioning-related measurement result (s) . Upon receiving 514 the measurement configuration information, the trustable device 502 may be configured to measure and report the first positioning-related measurement result (s) for the at least one reference device 120.
The trustable device 502 transmits 515 the first positioning-related measurement result (s) for positioning of the at least one reference device 120 to the first device 110. In some example embodiments, the first device 110 may configure more than one trustable device 502 to transmit the first positioning-related measurement result (s) associated with one or more same or different reference devices 120.
Upon receiving 520 the first positioning-related measurement result (s) from the trustable device (s) 502, the first device 110 determines 525 the at least one estimated location of the at least one reference device 120 and identifies 530 an invalid reference device from the at least one reference device if a mismatch is found between the at least one estimated location and the set of locations of valid reference devices for the target device 130. The first device 110 may apply a similar manner as discussed above with respect to the target device 130 to determine the at least one estimated location and identify the invalid reference device (s) .
In some example embodiments, the first device 110 may verify which reference device (s) 120 is an invalid reference device by applying an iterative process similar to the process 400 of Fig. 4. The difference lies in that in each round of iteration, the location of the trustable device 502 may not be updated as that of the target device 130 at block 420 because the valid location of the trustable 502 is known by the first device 110. The estimated locations of the reference devices 120 may be changed if a different one (s) reference device 120 is excluded.
In some example embodiments, after the first device 110 has identified one or more invalid reference devices 120, in some example embodiments, the first device 110 may also notify the target device 130 of the invalid reference device (s) by transmitting 535 an indication to the target device 130, as in the signaling flow 200. By receiving 540 the indication from the first device 110, the target device 130 can exclude the invalid reference device (s) from the positioning-related measurement, measurement reporting, and/or location estimations.
Example method embodiments
Fig. 6 shows a flowchart of an example method 600 implemented at a first device in accordance with some example embodiments of the present disclosure. For the purpose of discussion, the method 600 will be described from the perspective of the first device 110 with respect to Figs. 1, 2, and 5.
At block 610, the first device 110 receives, from a second device, at least one first positioning-related measurement result for positioning of at least one of a set of reference devices, the set of reference devices transmitting respective reference signals for positioning a target device. The second device may be the target device 130 in Fig. 1 and 2, or the trustable device 502 in Fig. 5.
At block 620, the first device 110 determines at least one estimated location of the at least one reference device based on the at least one first positioning-related measurement result and a location of the second device. At block 630, the first device 110 determines whether the at least one estimated location mismatches a set of locations of valid reference devices for the target device. If a mismatch is detected between the at least one estimated location and a set of locations of valid reference devices for the target device, at block 640, the first device 110 identifies an invalid reference device from the at least one reference device.
In some example embodiments, the first device 110 may transmit, to the second device, measurement configuration information to configure the second device to transmit the at least one first positioning-related measurement result for the at least one reference device 120.
In some example embodiments, the at least one first positioning-related measurement result may comprise at least one timing measurement associated with the at least one reference device 120, at least one angle-related measurement associated with the at least one reference device 120, and at least one received power-related measurement associated with the at least one reference device 120. In some example embodiments, the at least one angle-related measurement may comprise measurement information indicating a relative angle between a direction of arrival at the second device from the at least one reference device 120 and a direction of arrival at the second device from a further reference device of the set of reference devices. Alternatively, or in addition, the at least one angle-related measurement may comprise measurement information indicating at least one AoD of the at least one reference signal at the at least one reference device 120.
In some example embodiments, to perform location estimation of the at least one reference device 120, the first device 110 may determine, based on the at least one first positioning-related measurement result, at least one estimated distance between the at least one reference device 120 and the second device and at least one estimated angle of a direction of arrival at the at least one reference device 120 from the second device. The at least one estimated location of the at least one reference device 120 may be determined based on the at least one estimated distance, the at least one estimated angle, and the location of the second device.
In some example embodiments, the second device is trustable by the first device 110, such as the trustable device 502 in Fig. 5. The location of the second device may be known at the first device 110.
In some example embodiments, the second device is the target device 130 that is being positioned. In such cases, the first device 110 may receive, from the second device, a set of second positioning-related measurement results for positioning of the second device, each being associated with one of the set of reference devices. The first device 110 may determine an estimated location of the second device based on the set of second positioning-related measurement results, as the location of the second device.
In some example embodiments, the at least one reference device 120 to be verified may comprise a plurality of reference devices in the set of reference devices. In order to identify an invalid reference device from the plurality of reference devices, the first device 110 may first exclude a predetermined number of reference devices from the plurality of reference devices to obtain remaining reference devices 120. The predetermined number may be increased from one in an iterative process until the invalid reference device (s) is identified. The first device 110 may update the estimated locations of the remaining reference devices 120 based on the location of the second device and the at least one first positioning-related measurement result associated with the remaining reference devices 120. If the updated estimated locations of the remaining reference devices 120 match the set of locations of valid reference devices, the first device 110 may identify the predetermined number of reference devices that are excluded in the current round of iteration, as invalid reference devices.
In some example embodiments, the second device is the target device 130, and a set of second positioning-related measurement results associated with the set of reference devices are available for the first device 110. In such case, the location of the second device may be updated based on second positioning-related measurement results associated with the remaining reference devices 120 in each round of iteration. The estimated locations of the remaining reference devices 120 may be determined based on the updated location of the second device and the at least one first positioning-related measurement result associated with the remaining reference devices 120. In some example embodiments, if the updated estimated locations of the remaining reference devices 120 match the set of locations of valid reference devices and the invalid reference device (s) are identified, the first device 110 may determine the currently updated estimated location of the second device as a valid location of the target device 130.
In some example embodiments, if one or more certain reference devices 120 are identified as invalid reference devices, the first device 110 may transmit, to the target device 130, an indication that the one or more certain reference device are invalid reference devices.
In some example embodiments, if one or more reference devices 120 are identified as invalid reference devices, the first device 110 may cause a mitigation action to be performed against the invalid reference devices, in order to remove potential security issues in the communication network.
Fig. 7 shows a flowchart of an example method 700 implemented at a second device in accordance with some example embodiments of the present disclosure. For the purpose of discussion, the method 700 will be described from the perspective of the second device, which may be the target device 130 in Figs. 1 and 2, and the trustable device 502 in Fig. 5.
At block 710, the second device determines at least one first positioning-related measurement result for positioning of at least one of a set of reference devices by measuring at least one reference signal from the at least one reference device 120s. The set of reference devices transmit respective reference signals for positioning a target device 130. At block 720, the second device transmits the at least one first positioning-related measurement result to a first device 110 for determining at least one estimated location of the at least one reference device 120.
In some example embodiments, the second device may receive, from the first device 110, measurement configuration information configuring the second device to report the at least one first positioning-related measurement result associated with the at least one reference device 120.
In some example embodiments, the at least one first positioning-related measurement result may comprise at least one of the following: at least one timing measurement associated with the at least one reference device 120, at least one angle-related measurement associated with the at least one reference device 120, and at least one received power-related measurement associated with the at least one reference device 120. In some example embodiments, the at least one angle-related measurement may comprise information indicating at least one of the following: a relative angle between a direction of arrival of the reference signal at the second device from the at least one reference device and a direction of arrival of the reference signal at the second device from a further reference device of the set of reference devices, and at least one angle of departure of the at least one reference signal at the at least one reference device.
In some example embodiments, the second device is trustable by the first device 110, and the location of the second device is known at the first device 110.
In some example embodiments, the second device is the target device 130. In such case, the second device may determine a set of second positioning-related measurement results for the second device by measuring the respective reference signals from the set of reference devices. The set of second positioning-related measurement results may be reported to the first device 110.
In some example embodiments, the second device may receive, from the first device 110, an indication that a reference device of the at least one reference device 120 is an invalid reference device.
Example apparatus embodiments
In some example embodiments, a first apparatus capable of performing any of the method 600 (for example, the first device 110) may comprise means for performing the respective operations of the method 600. The means may be implemented in any suitable form. For example, the means may be implemented in a circuitry or software module. The first apparatus may be implemented as or included in the first device 110.
In some example embodiments, the first apparatus comprises means for receiving, from a second apparatus, at least one first positioning-related measurement result for positioning of at least one of a set of reference devices, the set of reference devices transmitting respective reference signals for positioning a target device; means for determining at least one estimated location of the at least one reference device based on the at least one first positioning-related measurement result and a location of the second apparatus; and means for, in response to a mismatch between the at least one estimated location and a set of locations of valid reference devices for the target device, identifying an invalid reference device from the at least one reference device.
In some example embodiments, the at least one first positioning-related measurement result comprises at least one of the following: at least one timing measurement associated with the at least one reference device, at least one angle-related measurement associated with the at least one reference device, and at least one received power-related measurement associated with the at least one reference device. In some example embodiments, the at least one angle-related measurement comprises measurement information indicating at least one of the following: a relative angle between a direction of arrival at the second apparatus from the at least one reference device and a direction of arrival at the second apparatus from a further reference device of the set of reference devices, and at least one angle of departure of the at least one reference signal at the at least one reference device.
In some example embodiments, the means for determining the at least one estimated location of the at least one reference device comprises means for determining, based on the at least one first positioning-related measurement result, at least one estimated distance between the at least one reference device and the second apparatus and at least one estimated angle of a direction of arrival at the at least one reference device from the second apparatus; and means for determining the at least one estimated location of the at least one reference device based on the at least one estimated distance, the at least one estimated angle, and the location of the second apparatus.
In some example embodiments, the second apparatus is trustable by the first apparatus, and the location of the second apparatus is known at the first apparatus.
In some example embodiments, the first apparatus further comprises means for receiving, from the second apparatus, a set of second positioning-related measurement results for positioning of the second apparatus; and means for determining an estimated location of the second apparatus based on the set of second positioning-related measurement results, as the location of the second apparatus.
In some example embodiments, the at least one reference device comprises a plurality of reference devices in the set of reference devices. In some example embodiments, the means for identifying an invalid reference device from the at least one reference device comprises: means for excluding a predetermined number of reference devices from the plurality of reference devices to obtain remaining reference devices; means for updating the estimated locations of the remaining reference devices based on the location of the second apparatus and the at least one first positioning-related measurement result associated with the remaining reference devices; and means for, in response to the updated estimated locations of the remaining reference devices matching the set of locations of valid reference devices, identifying the predetermined number of excluded reference devices as invalid reference devices.
In some example embodiments, the second apparatus comprises the target device, and a set of second positioning-related measurement results for positioning of the second device are available for the first device. In some example embodiments, the means for updating the estimated locations of the remaining reference devices comprises means for updating the location of the second apparatus based on second positioning-related measurement results associated with the remaining reference devices; and means for updating the estimated locations of the remaining reference devices based on the updated location of the second apparatus and the at least one first positioning-related measurement result associated with the remaining reference devices.
In some example embodiments, the second apparatus further comprises means for, in response to the updated estimated locations of the remaining reference devices matching the set of locations of valid reference devices, determine the updated estimated location of the second apparatus as a valid location of the target device.
In some example embodiments, the second apparatus further comprises means for, in accordance with a determination that a certain reference device of the at least one reference device is identified as an invalid reference device, transmit, to the target device, an indication that the certain reference device is an invalid reference device.
In some example embodiments, the second apparatus further comprises means for, in accordance with a determination that a reference device of the at least one reference device is identified as an invalid reference device, cause a mitigation action to be performed against the invalid reference device.
In some example embodiments, the second apparatus further comprises means for transmitting, to the second apparatus, measurement configuration information configuring the second apparatus to transmit the at least one first positioning-related measurement result for the at least one reference device.
In some example embodiments, the first apparatus further comprises means for performing other operations in some example embodiments of the method 600. In some example embodiments, the means comprises at least one processor; and at least one memory including computer program code, the at least one memory and computer program code configured to, with the at least one processor, cause the performance of the first apparatus.
In some example embodiments, a second apparatus capable of performing any of the method 700 (for example, the second device) may comprise means for performing the respective operations of the method 700. The means may be implemented in any suitable form. For example, the means may be implemented in a circuitry or software module. The second apparatus may be implemented as or included in the second device.
In some example embodiments, the second apparatus comprises means for determining at least one first positioning-related measurement result for positioning of at least one of a set of reference devices by measuring at least one reference signal from the at least one reference devices, the set of reference devices transmitting respective reference signals for positioning a target device; and means for transmitting the at least one first positioning-related measurement result to a first apparatus for determining at least one estimated location of the at least one reference device.
In some example embodiments, the at least one first positioning-related measurement result comprises at least one of the following: at least one timing measurement associated with the at least one reference device, at least one angle-related measurement associated with the at least one reference device, and at least one received power-related measurement associated with the at least one reference device.
In some example embodiments, the at least one angle-related measurement comprises information indicating at least one of the following: a relative angle between a direction of arrival of the reference signal at the second device from the at least one reference device and a direction of arrival of the reference signal at the second device from a further reference device of the set of reference devices, and at least one angle of departure of the at least one reference signal at the at least one reference device.
In some example embodiments, the second apparatus is trustable by the first apparatus, and the location of the second apparatus is known at the first apparatus.
In some example embodiments, the second apparatus is the target device. The second apparatus further comprises means for determining a set of second positioning-related measurement results for the second apparatus by measuring the respective reference signals from the set of reference devices, the set of second positioning-related measurement results being associated with the set of reference devices, respectively and means for transmitting the set of second positioning-related measurement results to the first apparatus.
In some example embodiments, the second apparatus further comprise means for receiving, from the first apparatus, an indication that a certain reference device of the at least one reference device is an invalid reference device.
In some example embodiments, the second apparatus further comprise means for receiving, from the first apparatus, measurement configuration information configuring the second apparatus to report the at least one first positioning-related measurement result associated with the at least one reference device.
In some example embodiments, the second apparatus further comprises means for performing other operations in some example embodiments of the method 700. In some example embodiments, the means comprises at least one processor; and at least one memory including computer program code, the at least one memory and computer program code configured to, with the at least one processor, cause the performance of the second apparatus.
Example device and medium embodiments
Fig. 8 is a simplified block diagram of a device 800 that is suitable for implementing example embodiments of the present disclosure. The device 800 may be provided to implement a communication device, for example, the first device 110, the target device 130, or the trustable device 510 as shown in Figs. 1 and 5. As shown, the device 800 includes one or more processors 810, one or more memories 820 coupled to the processor 810, and one or more communication modules 840 coupled to the processor 810.
The communication module 840 is for bidirectional communications. The communication module 840 has one or more communication interfaces to facilitate communication with one or more other modules or devices. The communication interfaces may represent any interface that is necessary for communication with other network elements. In some example embodiments, the communication module 840 may include at least one antenna.
The processor 810 may be of any type suitable to the local technical network and may include one or more of the following: general purpose computers, special purpose computers, microprocessors, digital signal processors (DSPs) and processors based on multicore processor architecture, as non-limiting examples. The device 800 may have multiple processors, such as an application specific integrated circuit chip that is slaved in time to a clock which synchronizes the main processor.
The memory 820 may include one or more non-volatile memories and one or more volatile memories. Examples of the non-volatile memories include, but are not limited to, a Read Only Memory (ROM) 824, an electrically programmable read only memory (EPROM) , a flash memory, a hard disk, a compact disc (CD) , a digital video disk (DVD) , an optical disk, a laser disk, and other magnetic storage and/or optical storage. Examples of the volatile memories include, but are not limited to, a random access memory (RAM) 822 and other volatile memories that will not last in the power-down duration.
A computer program 830 includes computer executable instructions that are executed by the associated processor 810. The program 830 may be stored in the memory, e.g., ROM 824. The processor 810 may perform any suitable actions and processing by loading the program 830 into the RAM 822.
The example embodiments of the present disclosure may be implemented by means of the program 830 so that the device 800 may perform any process of the disclosure as discussed with reference to Figs. 2 to 7. The example embodiments of the present disclosure may also be implemented by hardware or by a combination of software and hardware.
In some example embodiments, the program 830 may be tangibly contained in a computer readable medium which may be included in the device 800 (such as in the memory 820) or other storage devices that are accessible by the device 800. The device 800 may load the program 830 from the computer readable medium to the RAM 822 for execution. The computer readable medium may include any types of tangible non-volatile storage, such as ROM, EPROM, a flash memory, a hard disk, CD, DVD, and the like. Fig. 9 shows an example of the computer readable medium 900 which may be in form of CD, DVD or other optical storage disk. The computer readable medium has the program 830 stored thereon.
Generally, various embodiments of the present disclosure may be implemented in hardware or special purpose circuits, software, logic or any combination thereof. Some aspects may be implemented in hardware, while other aspects may be implemented in firmware or software which may be executed by a controller, microprocessor or other computing device. While various aspects of embodiments of the present disclosure are illustrated and described as block diagrams, flowcharts, or using some other pictorial representations, it is to be understood that the block, apparatus, system, technique or method described herein may be implemented in, as non-limiting examples, hardware, software, firmware, special purpose circuits or logic, general purpose hardware or controller or other computing devices, or some combination thereof.
The present disclosure also provides at least one computer program product tangibly stored on a non-transitory computer readable storage medium. The computer program product includes computer-executable instructions, such as those included in program modules, being executed in a device on a target physical or virtual processor, to carry out any of the methods as described above with reference to Figs. 2 to 7. Generally, program modules include routines, programs, libraries, objects, classes, components, data structures, or the like that perform particular tasks or implement particular abstract data types. The functionality of the program modules may be combined or split between program modules as desired in various embodiments. Machine-executable instructions for program modules may be executed within a local or distributed device. In a distributed device, program modules may be located in both local and remote storage media.
Program code for carrying out methods of the present disclosure may be written in any combination of one or more programming languages. These program codes may be provided to a processor or controller of a general purpose computer, special purpose computer, or other programmable data processing apparatus, such that the program codes, when executed by the processor or controller, cause the functions/operations specified in the flowcharts and/or block diagrams to be implemented. The program code may execute entirely on a machine, partly on the machine, as a stand-alone software package, partly on the machine and partly on a remote machine or entirely on the remote machine or server.
In the context of the present disclosure, the computer program code or related data may be carried by any suitable carrier to enable the device, apparatus or processor to perform various processes and operations as described above. Examples of the carrier include a signal, computer readable medium, and the like.
The computer readable medium may be a computer readable signal medium or a computer readable storage medium. A computer readable medium may include but not limited to an electronic, magnetic, optical, electromagnetic, infrared, or semiconductor system, apparatus, or device, or any suitable combination of the foregoing. More specific examples of the computer readable storage medium would include 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) , an optical fiber, a portable compact disc read-only memory (CD-ROM) , an optical storage device, a magnetic storage device, or any suitable combination of the foregoing.
Further, while operations are depicted in a particular order, this should not be understood as requiring that such operations be performed in the particular order shown or in sequential order, or that all illustrated operations be performed, to achieve desirable results. In certain circumstances, multitasking and parallel processing may be advantageous. Likewise, while several specific implementation details are contained in the above discussions, these should not be construed as limitations on the scope of the present disclosure, but rather as descriptions of features that may be specific to particular embodiments. Certain features that are described in the context of separate embodiments may also be implemented in combination in a single embodiment. Conversely, various features that are described in the context of a single embodiment may also be implemented in multiple embodiments separately or in any suitable sub-combination.
Although the present disclosure has been described in languages specific to structural features and/or methodological acts, it is to be understood that the present disclosure defined in the appended claims is not necessarily limited to the specific features or acts described above. Rather, the specific features and acts described above are disclosed as example forms of implementing the claims.

Claims

A first device comprising:

at least one processor; and

at least one memory including computer program code;

wherein the at least one memory and the computer program code are configured to, with the at least one processor, cause the device to:

receive, from a second device, at least one first positioning-related measurement result for positioning of at least one of a set of reference devices, the set of reference devices transmitting respective reference signals for positioning a target device;

determine at least one estimated location of the at least one reference device based on the at least one first positioning-related measurement result and a location of the second device; and

in response to a mismatch between the at least one estimated location and a set of locations of valid reference devices for the target device, identify an invalid reference device from the at least one reference device.
The first device of claim 1, wherein the at least one first positioning-related measurement result comprises at least one of the following: at least one timing measurement associated with the at least one reference device, at least one angle-related measurement associated with the at least one reference device, and at least one received power-related measurement associated with the at least one reference device.
The first device of claim 2, wherein the at least one angle-related measurement comprises measurement information indicating at least one of the following:

a relative angle between a direction of arrival at the second device from the at least one reference device and a direction of arrival at the second device from a further reference device of the set of reference devices, and

at least one angle of departure of the at least one reference signal at the at least one reference device.
The first device of claim 1, wherein the at least one memory and the computer program code are configured to, with the at least one processor, cause the first device to determine the at least one estimated location of the at least one reference device by:

determining, based on the at least one first positioning-related measurement result, at least one estimated distance between the at least one reference device and the second device and at least one estimated angle of a direction of arrival at the at least one reference device from the second device; and

determining the at least one estimated location of the at least one reference device based on the at least one estimated distance, the at least one estimated angle, and the location of the second device.
The first device of claim 1, wherein the second device is trustable by the first device, and the location of the second device is known at the first device.
The first device of claim 1, wherein the at least one reference device comprises a plurality of reference devices in the set of reference devices, and

wherein the at least one memory and the computer program code are configured to, with the at least one processor, cause the first device to identify an invalid reference device from the at least one reference device by:

excluding a predetermined number of reference devices from the plurality of reference devices to obtain remaining reference devices;

updating the estimated locations of the remaining reference devices based on the location of the second device and the at least one first positioning-related measurement result associated with the remaining reference devices; and

in response to the updated estimated locations of the remaining reference devices matching the set of locations of valid reference devices, identifying the predetermined number of excluded reference devices as invalid reference devices.
The first device of claim 6, wherein the second device is the target device, and a set of second positioning-related measurement results for positioning of the second device are available for the first device, and

wherein the at least one memory and the computer program code are configured to, with the at least one processor, cause the first device to update the estimated locations of the remaining reference devices by

updating the location of the second device based on second positioning-related measurement results associated with the remaining reference devices; and

updating the estimated locations of the remaining reference devices based on the updated location of the second device and the at least one first positioning-related measurement result associated with the remaining reference devices.
The first device of claim 6, wherein the at least one memory and the computer program code are configured to, with the at least one processor, further cause the first device to:

in response to the updated estimated locations of the remaining reference devices matching the set of locations of valid reference devices, determine the updated location of the second device as a valid location of the target device.
The first device of claim 1, wherein the at least one memory and the computer program code are configured to, with the at least one processor, further cause the first device to:

in accordance with a determination that a certain reference device of the at least one reference device is identified as an invalid reference device, transmit, to the target device, an indication that the certain reference device is an invalid reference device.
The first device of claim 1, wherein the at least one memory and the computer program code are configured to, with the at least one processor, further cause the first device to:

transmit, to the second device, measurement configuration information configuring the second device to transmit the at least one first positioning-related measurement result associated with the at least one reference device.
A second device comprising:

at least one processor; and

at least one memory including computer program code;

wherein the at least one memory and the computer program code are configured to, with the at least one processor, cause the second device to:

determine at least one first positioning-related measurement result for positioning of at least one of a set of reference devices by measuring at least one reference signal from the at least one reference devices, the set of reference devices transmitting respective reference signals for positioning a target device; and

transmit the at least one first positioning-related measurement result to a first device for determining at least one estimated location of the at least one reference device.
The second device of claim 11, wherein the at least one first positioning-related measurement result comprises at least one of the following: at least one timing measurement associated with the at least one reference device, and at least one angle-related measurement associated with the at least one reference device, and at least one received power-related measurement associated with the at least one reference device.
The second device of claim 12, wherein the at least one angle-related measurement comprises information indicating at least one of the following:

a relative angle between a direction of arrival of the reference signal at the second device from the at least one reference device and a direction of arrival of the reference signal at the second device from a further reference device of the set of reference devices, and

at least one angle of departure of the at least one reference signal at the at least one reference device.
The second device of claim 11, wherein the second device is trustable by the first device, and the location of the second device is known at the first device.
The second device of claim 11, wherein the at least one memory and the computer program code are configured to, with the at least one processor, further cause the second device to:

receive, from the first device, an indication that a certain reference device of the at least one reference device is an invalid reference device.
The second device of claim 11, wherein the at least one memory and the computer program code are configured to, with the at least one processor, further cause the second device to:

receive, from the first device, measurement configuration information configuring the second device to report the at least one first positioning-related measurement result associated with the at least one reference device.
A method comprising:

receiving, at a first device and from a second device, at least one first positioning-related measurement result for positioning of at least one of a set of reference devices, the set of reference devices transmitting respective reference signals for positioning a target device;

determining at least one estimated location of the at least one reference device based on the at least one first positioning-related measurement result and a location of the second device; and

in response to a mismatch between the at least one estimated location and a set of locations of valid reference devices for the target device, identifying an invalid reference device from the at least one reference device.
The method of claim 17, wherein the at least one first positioning-related measurement result comprises at least one of the following: at least one timing measurement associated with the at least one reference device, at least one angle-related measurement associated with the at least one reference device, and at least one received power-related measurement associated with the at least one reference device, and

wherein the at least one angle-related measurement comprises measurement information indicating at least one of the following:

a relative angle between a direction of arrival at the second device from the at least one reference device and a direction of arrival at the second device from a further reference device of the set of reference devices, and

at least one angle of departure of the at least one reference signal at the at least one reference device.
The method of claim 17, wherein determining the at least one estimated location of the at least one reference device comprises:

determining, based on the at least one first positioning-related measurement result, at least one estimated distance between the at least one reference device and the second device and at least one estimated angle of a direction of arrival at the at least one reference device from the second device; and

determining the at least one estimated location of the at least one reference device based on the at least one estimated distance, the at least one estimated angle, and the location of the second device.
The method of claim 17, wherein the second device is trustable by the first device, and the location of the second device is known at the first device.
The method of claim 17, wherein the at least one reference device comprises a plurality of reference devices in the set of reference devices, and wherein identifying an invalid reference device from the at least one reference device comprises:

excluding a predetermined number of reference devices from the plurality of reference devices to obtain remaining reference devices;

updating the estimated locations of the remaining reference devices based on the location of the second device and the at least one first positioning-related measurement result associated with the remaining reference devices; and

in response to the updated estimated locations of the remaining reference devices matching the set of locations of valid reference devices, identifying the predetermined number of excluded reference devices as invalid reference devices.
The method of claim 21, wherein the second device is the target device, and a set of second positioning-related measurement results for positioning of the second device are available for the first device, and

wherein updating the estimated locations of the remaining reference devices comprises:

updating the location of the second device based on second positioning-related measurement results associated with the remaining reference devices; and

updating the estimated locations of the remaining reference devices based on the updated location of the second device and the at least one first positioning-related measurement result associated with the remaining reference devices.
The method of claim 17, further comprising:

in accordance with a determination that a certain reference device of the at least one reference device is identified as an invalid reference device, transmitting, to the target device, an indication that the certain reference device is an invalid reference device.
A method comprising:

determining, at a second device, at least one first positioning-related measurement result for positioning of at least one of a set of reference devices by measuring at least one reference signal from the at least one reference devices, the set of reference devices transmitting respective reference signals for positioning a target device; and

transmitting the at least one first positioning-related measurement result to a first device for determining at least one estimated location of the at least one reference device.
A first apparatus comprising:

means for receiving, from a second apparatus, at least one first positioning-related measurement result for positioning of at least one of a set of reference devices, the set of reference devices transmitting respective reference signals for positioning a target device;

means for determining at least one estimated location of the at least one reference device based on the at least one first positioning-related measurement result and a location of the second apparatus; and

means for, in response to a mismatch between the at least one estimated location and a set of locations of valid reference devices for the target device, identifying an invalid reference device from the at least one reference device.
A second apparatus comprising:

means for determining at least one first positioning-related measurement result for positioning of at least one of a set of reference devices by measuring at least one reference signal from the at least one reference devices, the set of reference devices transmitting respective reference signals for positioning a target device; and

means for transmitting the at least one first positioning-related measurement result to a first apparatus for determining at least one estimated location of the at least one reference device.
A computer readable medium comprising program instructions for causing an apparatus to perform at least the method of any of claims 17 to 23, or the method of claim 24.