Providing and supporting location services via direct device-to-device connections

Abstract

The present application relates to aspects of supporting UE location services via a direct device-to-device connection (e.g., a sidelink connection) between UEs. Thus, a mobile telecommunications network apparatus for enabling a determination of a target communication device location is provided. The apparatus includes a first interface configured to provide communication with a mobile telecommunications network via the radio unit, and a second interface configured to provide direct device-to-device communication within proximity via the radio unit. The apparatus is configured to establish a direct device-to-device connection to a communication device within the proximity via the second interface. The apparatus then sends a location request message to the communication device via the established connection. The location request message includes a request to determine a location of a target communication device, and a precision parameter indicating a target precision for location determination. In response to the location request message, the apparatus receives a location response message from the communication device via the established connection, the location response message including data indicative of a location of the target communication device determined according to the accuracy parameter.

Description

BACKGROUND OF THE INVENTION

[0001] Modern public land mobile networks (PLMNs) support positioning services to connected user equipment (UEs). Currently supported positioning techniques are provided directly by the location functions of the PLMN (RAT-related) or are independent of the radio access technology (RAT). The positioning techniques provided by the PLMN rely on the connection to the PLMN via radio access network (RAN) nodes such as eNBs, NG-eNBs, or gNBs. RAT-independent techniques can be performed by a single UE without coordination with the PLMN (e.g., positioning via the Global Navigation Satellite System GNSS). In cases where the UE is outside the coverage area of the RAN node, RAT-related techniques may fail. Even when the target UE is within the coverage area of the RAN node, network-based positioning services may introduce unacceptable latency. Additionally, RAT-independent techniques may not be available (e.g., in indoor scenarios) or may not meet the expected accuracy or latency requirements.

[0002] 3GPP Release 16 introduced an extension to the 5G New Radio network that allows for direct device-to-device communication between UEs. This device-to-device communication standard is known as sidelink (SL) and uses the New Radio air interface of the 5G system. Sidelink provides a direct connection between UEs in close proximity to each other. Sidelink can provide a basis for providing accurate and low-latency positioning services that are available even outside the PLMN coverage area. However, currently available techniques do not provide a robust and efficient positioning process based on direct device-to-device communication such as sidelink. SUMMARY OF THE INVENTION

[0003] One aspect of the present invention is to provide a mobile telecommunications network apparatus for implementing improved positioning services for determining the location of a user equipment (UE) via a direct device-to-device connection.

[0004] To overcome the above deficiencies, a mobile telecommunications network device (i.e., UE) is presented. The device includes a first interface configured to provide communication with a mobile telecommunications network (e.g., a cellular network such as an LTE network or a 5G New Radio network) via a radio unit. The device also includes a second interface configured to provide direct device-to-device (i.e., UE-to-UE) communication within a proximity range via the radio unit. The device includes one or more processors configured to execute computer-readable instructions for implementing the determination of the location of a target communication device. The instructions cause the one or more processors to: establish a direct device-to-device connection to a communication device (i.e., UE) within the proximity range via the second interface, send a location request message to the communication device via the established connection, and receive a location response message from the communication device via the established connection. The location request message includes: a request to determine the location of the target communication device and one or more accuracy parameters indicating a target accuracy for location determination. The one or more accuracy parameters include at least one of the following: a relative accuracy parameter for distance determination, an absolute accuracy parameter, and an absolute accuracy parameter for direction determination. The location response message includes: data indicating the location of the target communication device determined according to the one or more accuracy parameters.

[0005] In a further aspect, a mobile communication network device (i.e., UE) is provided. The device includes a first interface configured to provide communication with a mobile communication network (e.g., a cellular network such as an LTE network or a 5G New Radio network) via a radio unit. The device also includes a second interface configured to provide direct device-to-device communication within a proximity range via the radio unit. The device includes one or more processors configured to execute computer-readable instructions for implementing the determination of the location of a target communication device. The instructions cause the one or more processors to: establish a direct device-to-device connection to a communication device (i.e., UE) within the proximity range via the second interface, receive a location request message from the communication device via the established connection, determine the location of the target communication device, and send a location response message to the communication device via the established connection. The location request message includes: a request to determine the location of the target communication device and one or more accuracy parameters indicating a target accuracy for location determination. The one or more accuracy parameters include at least one of the following: a relative accuracy parameter for distance determination, an absolute accuracy parameter, and an absolute accuracy parameter for direction determination. The determination of the location of the target location device is performed according to the one or more accuracy parameters. The location response message includes: data indicating the determined location of the target communication device.

[0006] In another aspect, a mobile telecommunications network device (i.e., UE) is provided, which includes a first interface configured to provide communication with a mobile telecommunications network (e.g., a cellular network such as an LTE network or a 5G New Radio network) via a radio unit. The device further includes a second interface configured to provide direct device-to-device communication within a proximity range via the radio unit. The device includes one or more processors configured to execute computer-readable instructions for implementing discovery of a communication device for device location determination. The instructions cause the one or more processors to: establish a direct device-to-device connection to a first communication device (i.e., UE) within the proximity range via the second interface, receive a positioning request message from the first communication device via the established connection, the positioning request message including: a request to discover a second communication device (e.g., UE) within the proximity range. Subsequently, the instructions cause the one or more processors to: discover the second communication device according to the received positioning request message, and send a positioning response message via the established connection to the first communication device, the positioning response message indicating that the second communication device has been discovered.

[0007] In yet another aspect, a mobile telecommunications network device (i.e., UE) is provided, which includes a first interface configured to provide communication with a mobile telecommunications network (e.g., a cellular network such as an LTE network or a 5G New Radio network) via a radio unit. The device further includes a second interface configured to provide direct device-to-device communication within a proximity range via the radio unit. The device includes one or more processors configured to execute computer-readable instructions for assisting in determining the location of a target communication device (i.e., target UE). The instructions cause the one or more processors to: establish a direct device-to-device connection to a communication device (i.e., UE) within the proximity range via the second interface, and send an auxiliary data activation request message to the communication device via the established connection. The auxiliary data activation request message includes: a request to activate the transmission of auxiliary data by sending a positioning reference signal to the target communication device. The auxiliary data activation request message is configured to cause the communication device to: select a configuration type for the positioning reference signal, and according to the selected configuration type, send the positioning reference signal to the target communication device via the direct device-to-device connection. The configuration type specifies the attributes of the positioning reference signal, which is configured to enable the target communication device to perform measurements based on the positioning reference signal for determining the location of the target communication device.

[0008] In another aspect, a mobile telecommunications network device (i.e., UE) is provided, which includes a first interface configured to provide communication with a mobile telecommunications network (e.g., a cellular network such as an LTE network or a 5G New Radio network) via a radio unit. The device further includes a second interface configured to provide direct device-to-device communication within a proximity range via the radio unit. The device includes one or more processors configured to execute computer-readable instructions for assisting in determining the location of a target communication device (i.e., the target UE). The instructions cause the one or more processors to: establish a direct device-to-device connection to a communication device (i.e., UE) within the proximity range via the second interface, and receive an auxiliary data activation request message from the communication device via the established connection. The auxiliary data activation request message includes: a request to activate the transmission of auxiliary data by sending a positioning reference signal to the target communication device. The instructions further cause the one or more processors to: select a configuration type for the positioning reference signal in response to receiving the auxiliary data activation request message, and send the positioning reference signal to the target communication device via the direct device-to-device connection through the second interface according to the selected configuration type. The configuration type specifies the attributes of the positioning reference signal. The positioning reference signal is configured such that the target communication device can perform measurements based on the positioning reference signal for determining the location of the target communication device. BRIEF DESCRIPTION OF THE DRAWINGS

[0009] Embodiments and aspects of the present invention will be described in the following description in conjunction with the accompanying drawings, in which

[0010] Figure 1 is a diagram showing a conventional 3GPP telecommunications network architecture for providing network-based location services to user equipment;

[0011] Figure 2 is a diagram showing three exemplary network configurations in which location services can be provided;

[0012] Figure 3 is a diagram illustrating an exemplary configuration of a mobile telecommunications network device;

[0013] Figure 4 is an exemplary flowchart showing the signal flow between multiple communication devices for client-initiated location determination of a target user equipment via a direct device-to-device connection;

[0014] Figure 5 is an exemplary flowchart illustrating the signal flow between multiple communication devices for target-initiated location determination of a target user equipment via a direct device-to-device connection;

[0015] Figure 6is an exemplary flowchart showing a signal flow between multiple communication devices for activating an auxiliary data transmission for positioning a target user equipment; and

[0016] Figure 7 is an exemplary flowchart showing another signal flow between multiple communication devices for activating an auxiliary data transmission for positioning a target user equipment. Detailed Description

[0017] Reference will now be made in detail to the exemplary embodiments, which are illustrated in the accompanying drawings, wherein like reference numerals refer to like elements unless otherwise indicated.

[0018] 1. Support for Positioning in Mobile Communication Networks

[0019] In Release 15 (Rel-15) of the 3GPP standard, the 5G air interface (New Radio NR) only supports cell ID and positioning methods independent of radio access technology (RAT). The positioning of a UE with a cell ID is based on the known location of the cell tower and the signal strength from the cell tower measured at the UE. The UE can identify the cell tower that sent the received signal by the cell ID of the cell tower sent together with the signal. The supported RAT-independent technologies include UE positioning via the Global Navigation Satellite System (GNSS, such as GPS, Galileo, etc.).

[0020] To meet the positioning requirements for regulatory (i.e., emergency services) and commercial use cases (such as Industrial Internet of Things IIoT), additional positioning methods have been specified in 3GPP Release 16. These additional positioning methods include: RAT-related methods in both supported frequency ranges FR1 and FR2, and RAT-independent positioning methods such as Precise Point Positioning (PPP) and Real-Time Kinematic technology (RTK). A list of RAT-related positioning methods supported in 3GPP Release 16 is provided in Table 1. These methods rely on the coordination of several PLMN network elements to provide positioning services for the target UE. Some of these methods can be performed by the target UE itself, but rely on additional assistance from the Location Management Function (LMF) of the network and / or one or more Next Generation Radio Access Network (NG-RAN) nodes (such as gNB or NG-eNB). Other supported methods are not performed by the target UE itself, but by other network elements (such as LMF or NG-RAN nodes).

[0021]

[0022] Table 1

[0023] The supported positioning methods include downlink and uplink time difference of arrival (DL-TDOA and UL-TDOA). In the downlink variant, the UE receives measurement signals (e.g., positioning reference signal PRS) from at least three network transmission points (e.g., transmission and reception points TRP in a 5G network or separate base stations), and evaluates the time difference of arrival of these signals. Together with the known positions of the transmission points, the UE can determine its own position. In the case of the uplink, the measurement signals are sent by the UE and received by at least three network receivers (e.g., TRP or base station). Based on the time difference of the received signals and the positions of the receiver points, the position of the UE can be determined.

[0024] The supported positioning methods downlink angle of departure (DL-AoD) and uplink angle of arrival (UL-AoA) are also based on the exchange of measurement signals (e.g., PRS) between the target UE and multiple network points (i.e., TRP or base station). These techniques evaluate the signal angles at the UE (downlink) or network points (uplink) and the known positions of the network points to determine the position of the target UE (i.e., positioning).

[0025] In the multi-round-trip time (multi-RTT) positioning method, the target UE position is determined based on measurements performed at both the target UE and network points (e.g., TRP or base station). The measurements performed at the UE and TRP are time difference measurements between the transmission and reception of the measurement signals, which are used by a network function (e.g., LMF) to determine the round-trip time and the final position of the target UE.

[0026] Finally, new radio enhanced cell ID (NR E-CID) positioning refers to techniques that use UE and / or NR radio resource related measurements to improve UE position estimation. According to TS 38.215, UE measurements can include synchronization signal RSRP (SS-RSRP) or synchronization signal RSRQ (SS-RSRQ). Measurements at the base station (e.g., NG-eNB or gNB) can include uplink angle of arrival and timing advance.

[0027] The application of these techniques has been further improved in 3GPP Release 17, enabling conventional 5G positioning services to meet the positioning requirements for commercial use cases, and in particular for the IIoT use cases listed in Table 2.

[0028]

[0029] Table 2

[0030] In a 5G system (5GS) architecture applicable to the positioning of a target UE, the target UE location is determined by the target UE itself or by a location server (e.g., LMF) according to the applied positioning method. To exchange positioning-related information (e.g., location-related measurements, location estimates, assistance data), 3GPP TS 37.355 specifies the LTE positioning protocol (LPP). LPP is a point-to-point positioning protocol used between a location server (e.g., LMF) and the target UE, which supports positioning and location-related services for the target device.

[0031] Figure 1 An exemplary 5GS architecture 100 for positioning a target UE 110 is shown. Figure 1 It includes 5GS components related to LPP messaging and additional components for providing LCS services. The latter will be discussed in detail in the next section.

[0032] Exemplary LPP messaging between the LMF 140 and the target UE 110 may include the following components: the target UE 110, an NG-RAN node 120 (e.g., an NG-eNB or gNB), an access and mobility management function (AMF) 130, and the LMF 140. LPP messages are carried as transparent protocol data units (PDUs) using an appropriate protocol on intermediate network interfaces.

[0033] In a first step, the LMF 140 sends an LPP message to the AMF 130. The LPP message can be a request capability message that requests the target UE 110 to send its positioning capabilities. The AMF 130 can transmit the received LPP information to the NG-RAN node 120 by including the LPP message in an LPP message container of a downlink non-access stratum (DL NAS) transport message. In the next step, the NG-RAN node 120 can transmit the received LPP message container to the target UE 110 by including the LPP message container in a radio resource control (RRC) DLInformationTransfer message specified in 3GPP TS 38.331. After receiving the request capability LPP message, the target UE 110 can generate a provide capability LPP message as a response. Then, the target UE 110 can send the provide capability LPP message to the NG-RAN node 120 by including the LPP message in an RRC ULInformationTransfer message specified in TS 38.331. Next, the NG-RAN node 120 can transmit the LPP message received from the target UE 110 to the AMF 130 by including the LPP message in an LPP message container of an UL NAS transport message. Finally, the AMF 130 can extract the LPP message from the received NAS message / LPP message container and send it to the LMF 140.

[0034] 2. Location Services

[0035] The Location Services (LCS) features in 3GPP provide mechanisms to support mobile location services for operators, subscribers, and third-party service providers. Examples of location-based services include emergency services, tracking services, location-based information services (navigation, city sightseeing, location-related content broadcasting, mobile yellow pages, etc.). Location information can be requested by and reported to a client (application) associated with the UE, or by a client within the 5G Core (5GC) or attached to the 5G Core. Referring again to Figure 1 , the complete system depicted in the figure shows an exemplary LCS architecture where an external LCS client 160 requests the current location of the target UE 110 from the 5GC.

[0036] The external LCS client 160 interacts with the Gateway Mobile Location Center (GMLC) 150 for obtaining location information for one or more target UEs 110. The LCS client 160 can reside in the UE and can be implemented as hardware or software (e.g., an application). The GMLC 150 is the first node accessed by the external LCS client 160 in the PLMN and serves as a location server for providing location information to external applications.

[0037] The LMF 140 manages the overall coordination and scheduling of resources required to register or access the target UE 110 to / from the 5GC. The LMF 140 also calculates or verifies the final location and any speed estimates, and may estimate the achieved accuracy. The LMF 140 processes location service requests, which may include transmitting assistance data to the target UE 110 to assist UE-based and / or UE-assisted positioning, and / or may include the positioning of the target UE 110. Then, the LMF 140 returns the location estimate for the target UE 110 to the AMF 130. In the case where a location service is requested by an entity other than the AMF 130 (e.g., the GMLC 150 or the target UE 110), the AMF 130 returns the location result to that entity. In the control plane (C-plane), the LMF 140 acts as a location server.

[0038] The AMF 130 includes functions responsible for managing the positioning of the target UE 110 for all types of location requests. The AMF 130 receives a request for some location services associated with a specific target UE 110 from another entity (e.g., the GMLC 150 or the target UE 110), or the AMF 130 itself decides to initiate a certain location service on behalf of a specific target UE 110 (e.g., for an emergency call from the target UE 110). The AMF 130 then sends a location service request to the LMF 140.

[0039] The NG-RAN nodes (e.g., NG-eNB or gNB) 120 participate in processing various positioning procedures, including the positioning of the target UE 110, the provision of location-related information not associated with a specific target UE 110, and the transmission of positioning messages between the AMF 130 or the LMF 140 and the target UE 110.

[0040] The target UE 110 is a UE whose absolute or relative location will be obtained by the network or by the target UE 110 itself. The relative location is determined with respect to a reference location, and the absolute location is determined within an absolute coordinate system (such as a global coordinate system).

[0041] NRPPa is the C-plane radio network layer signaling protocol between the NG-RAN nodes (e.g., NG-eNB, gNB) 120 and the LMF 140.

[0042] The following types of location requests are specified in 3GPP:

[0043] · Network-Induced Location Request (NI-LR): The serving AMF 130 for the target UE 110 initiates the positioning of the target UE 110 for regulatory services (e.g., emergency calls from the target UE 110), or for the verification of the location (country or international region) of the target UE 110 for NR satellite access.

[0044] · Mobile-Terminated Location Request (MT-LR): The LCS client 160, either outside or inside the serving PLMN, sends a location request to the PLMN for the location of the target UE 110.

[0045] · Mobile-Originated Location Request (MO-LR): The target UE 110 sends a request to the serving PLMN for location-related information of the target UE 110 itself.

[0046] 3. NR Sidelink Communication and Discovery

[0047] Modern positioning use cases (such as vehicle-to-everything (V2X) use cases, public safety regulatory requirements, IIoT, and other commercial use cases) require even higher accuracy requirements, as achievable by the technologies introduced in 3GPP Release 17. A possible solution to achieve higher accuracy and lower latency is sidelink (SL) positioning. The purpose of SL positioning is to determine the location of the target UE 110 by using SL positioning methods (such as RTT-type solutions using SL, SL AoA, and SL-TDOA). These positioning methods rely on direct device-to-device communication on the sidelink, rather than communication with PLMN network entities (e.g., RAN nodes or LMF). The SL positioning method is based on PRS (SL PRS) sent through the PC5 interface.

[0048] The sidelink was introduced in 3GPP Release 16 to provide direct device-to-device communication between UEs based on 5G radio technology. The sidelink uses the new radio air interface of 5GS. Therefore, sidelink communication is based on the same radio technology (e.g., physical layer) as the air interface (Uu interface) used to connect a UE to a 5G-enabled base station (e.g., NG-eNB or gNB). This means that the sidelink sends data between UEs via the same transmitter and receiver (or transceiver in some cases), the same antennas, and the same frequency range, or at least a part of the same frequency range as those used by the Uu interface to send and receive data packets from a gNB or NG-eNB. The sidelink provides a direct connection between UEs that are in proximity to each other. In this case, a direct connection means that a message sent via the sidelink is not relayed from a first UE to a second UE through the network via one or more NG-RAN nodes 120 (e.g., NG-eNB or gNB). Since the sidelink only works within a proximity range, when two UEs are too far apart from each other, a sidelink device-to-device connection between the first UE and the second UE may not be possible. In this case, the sidelink connection can be relayed via a third UE that is within the proximity range of the first UE and the second UE.

[0049] Sidelink (SL) communication is introduced to support vehicle-to-everything (V2X) and non-V2X services. The interface for SL communication (transmission / reception) between two neighboring UEs is denoted as PC5. Figure 2 Scenarios supported for SL communication are shown, where two UEs are located within the in-cell (IC), partial coverage (PC), and out-of-coverage (OOC) areas of a cell. In the OOC scenario, both the first UE 220 and the second UE 230 are outside the coverage area 210 of an NG-RAN node (e.g., NG-eNB or gNB) 120. Therefore, neither UE 220 nor UE 230 can establish a connection to the NG-RAN node 120 via the air interface (Uu interface). However, UE220 and 230 are within proximity to each other and are able to establish a direct device-to-device (UE-to-UE) connection 240 (e.g., a sidelink connection via the PC5 interface). The OOC scenario is not limited to two UEs. This scenario can include three or more UEs that are outside the coverage of the NG-RAN node 120 but can be connected to at least one of the other UEs via a direct device-to-device connection 240.

[0050] In the PC scenario, at least one UE 220 is within the coverage area 210 of the NG-RAN node 120. Another UE 230 is outside the coverage area of the NG-RAN node 120 but within the proximity range of the UE 220. The UE 220 is connected to the NG-RAN via the air interface 250 (e.g., Uu interface) and communicates with network services (e.g., LMF 140) or with other UEs via the PLMN network. Since the UE 230 is outside the coverage area of the NG-RAN, the UE 230 is not (directly) connected to the PLMN network via the air interface connection 250 to the NG-RAN 120. However, the UE 230 can communicate with the UE 220 via a direct device-to-device connection 240 (e.g., sidelink connection via the PC5 interface). This scenario is not limited to two UEs, but can include three or more UEs, where at least one UE is outside the coverage area 210 of the NG-RAN node but within the proximity range of another UE within the coverage area 210 of the NG-RAN node, such that the two UEs can communicate via a direct device-to-device connection 240 (e.g., sidelink connection via the PC5 interface).

[0051] The IC scenario involves a case where two or more UEs (e.g., UE 220 and UE 230) are within the coverage area 210 of the NG-RAN node 120 and are connected to the NG-RAN node 120 via the air interface 250 (e.g., Uu interface). Thus, all UEs can communicate with network services (e.g., LMF 140) or with other UEs via the PLMN network. Additionally, at least some of the two or more UEs (e.g., UE 220 and UE 230) are within the proximity range of each other and are connected via a direct device-to-device connection 240 (e.g., sidelink connection via the PC5 interface), enabling them to communicate with each other without relaying the communication through the PLMN network.

[0052] The transmission and reception of user traffic via the direct device-to-device interface 240 (e.g., PC5 interface) can be supported for unicast, multicast, and broadcast transmissions. The transmission and reception of signaling traffic via this interface can be supported only for unicast transmissions. The direct device-to-device connection 240 via the PC5 (e.g., sidelink connection) is defined as a logical connection between a pair of source and destination layer 2 IDs. The source and destination layer 2 IDs respectively identify the sender and the target of the direct device-to-device communication (e.g., sidelink communication). For the propagation type, the corresponding pair of the source layer 2 ID and the destination layer 2 ID is used. 3GPP sidelink communication is based on the 3GPP proximity-based service (ProSe) feature.

[0053] To enable direct device-to-device communication (e.g., sidelink communication) between neighboring UEs (e.g., UE 220 and UE 230), the UE may need to perform a discovery process (e.g., sidelink discovery). The discovery process (e.g., sidelink discovery process) can be used by one or more UEs (e.g., UE 220) to discover neighboring other UEs (e.g., UE 230), or to be discovered by those other UEs. For example, UE 220, which wants to discover neighboring other UEs, can send a discovery message through an interface for direct device-to-device communication (e.g., PC5 interface). Neighboring other UEs (e.g., UE 230) can monitor the discovery message, and if they want to be discovered, they can respond with a discovery response message. After discovery, UE 220 can establish a direct device-to-device communication connection 240 (e.g., sidelink connection) with each of the responding UEs (e.g., UE 230). NR sidelink communication and discovery are described in 3GPP TS23.304.

[0054] One of the challenges in developing a robust process for SL positioning is that the SL positioning process must address multiple different coverage scenarios (i.e., IC, PC, and OOC scenarios), and thus these scenarios must provide efficient support for both PC5-only and combined PC5-Uu operation scenarios.

[0055] 4. Sidelink Positioning Terminology

[0056] Embodiments enable UE positioning via direct device-to-device communication (e.g., sidelink communication) in all three discussed coverage scenarios. This is achieved through coordinated interaction of multiple UEs or other devices. The following listed terms are used to refer to the roles of specific UEs or other devices participating in a positioning session via direct device-to-device communication (e.g., sidelink positioning session):

[0057] The initiator device initiates a positioning or ranging session (e.g., sidelink positioning or ranging session). In IC or PC scenarios, the initiator device can be a network entity (e.g., NG-eNB, gNB, AMF, LMF), a UE, or a roadside unit (RSU). In OOC scenarios, the initiator device can be a UE or an RSU of UE type.

[0058] The responder device responds to a positioning or ranging session (e.g., sidelink positioning or ranging session) from the initiator device. In IC or PC scenarios, the responder device can be a network entity (e.g., NG-eNB, gNB, AMF, LMF), a UE, or a roadside unit (RSU). In OOC scenarios, the responder device can be a UE or an RSU of UE type.

[0059] The target UE (such as target UE 110) is the UE of interest, and its location (absolute or relative) will be obtained by the network (IC or PC scenarios) or by the UE itself (IC, PC, and OOC scenarios).

[0060] The anchor UE supports the positioning of the target UE (e.g., target UE 110), for example, by sending and / or receiving reference signals for positioning on the direct device-to-device interface (e.g., PC5 interface), providing positioning-related information, etc. The anchor UE may also be referred to as the sidelink reference UE.

[0061] When direct ranging or positioning between the anchor UE and target UE 110 cannot be supported (e.g., because target UE 110 and the anchor UE are not in the proximity range), the assisting UE supports ranging / positioning between the anchor UE and the target UE (e.g., target UE 110) via the direct device-to-device connection 240 through the direct device-to-device interface (e.g., PC5 interface). The measurements, ranging results, or positioning results between the assisting UE and the anchor UE and between the assisting UE and target UE 110 are determined and used to derive the ranging or positioning result between target UE 110 and the anchor UE.

[0062] The positioning server UE (e.g., sidelink positioning server UE) provides position calculation for positioning- and ranging-based services (e.g., sidelink positioning and ranging). The positioning server UE interacts with other UEs through the direct device-to-device interface (e.g., PC5 interface) as needed to calculate the position of target UE 110. If the corresponding UE supports position calculation, target UE 110 or the anchor UE can act as the positioning server UE.

[0063] The positioning client UE or client UE (e.g., sidelink positioning client UE) is a third-party UE other than the anchor UE and target UE 110, which initiates a ranging or positioning service request on behalf of the application residing on it. In some embodiments, target UE 110 itself initiates a ranging or positioning service request and thus acts as the client UE.

[0064] In addition to the above roles of UEs or devices in the UE positioning process, the following terms are relevant to the subsequent discussion:

[0065] Sidelink positioning refers to positioning a UE using reference signals sent through direct device-to-device communication via the corresponding interface (e.g., sidelink and PC5 interfaces) to obtain absolute position, relative position, or ranging information.

[0066] Ranging refers to determining the distance and / or direction (e.g., angle) between target UE 110 and another entity (e.g., the anchor UE).

[0067] Figure 3 Depicts an exemplary configuration of a mobile telecommunications network device 300 that may participate in a process related to the determination of the location (e.g., positioning or ranging) of a target UE 110 described subsequently in one of the roles described above. The depicted mobile telecommunications network device 300 may act as a target UE (e.g., target UE 110), an anchor UE, a positioning server UE, an assisting UE, and / or a client UE.

[0068] The mobile telecommunications network device 300 includes a memory 320, a processor 330, a UE-to-UE interface 340, a network interface 350, and a radio unit 360. The memory 320 may be a volatile memory (e.g., DRAM or SRAM) or a non-volatile memory (e.g., SDD or HDD storage device). The memory 320 stores computer-readable instructions 310. The processor 330 is configured to execute the instructions 310. Executing the instructions 310 may cause the processor 330 to implement a positioning process, such as Figures 4 to 7 the processes presented. The processor 330 controls the network interface 350 and the UE-to-UE interface 340. The network interface 350 is configured to connect the device to a mobile telecommunications network (e.g., a PLMN, such as an LTE network or a 5G NR network). The network interface 350 may provide an air interface 250 (e.g., the Uu interface) configured to connect the device to a RAN node or an NG-RAN node (e.g., an eNB, an NG-eNB, or a gNB).

[0069] The UE-to-UE interface 340 is configured to provide one or more direct device-to-device connections (e.g., sidelink connections) to one or more other mobile telecommunications network devices 300. The UE-to-UE interface 340 may be a PC5 interface for providing sidelink connections. The direct device-to-device connection does not involve network elements other than the UE. In particular, the direct device-to-device connection does not include a connection to a PLMN via an NG-RAN node (e.g., an eNB, an NG-eNB, or a gNB). The network interface 350 and / or the UE-to-UE interface 340 may be implemented in software by the computer-readable instructions 310. Alternatively or additionally, the network interface 350 and / or the UE-to-UE interface 340 may be implemented fully or partially in dedicated hardware (such as an application-specific integrated circuit).

[0070] The radio unit 360 provides radio technologies for enabling connections via the network interface 350 and the UE-to-UE interface 340. The radio unit 360 includes a transmitter and a receiver or a transceiver (not shown) configured to transmit and receive radio signals via one or more antennas 370. The antennas 370 are configured to transmit and receive radio signals within a frequency range corresponding to the supported radio technology (e.g., LTE or 5G NR). The interfaces 350 and 340 are configured to provide communication and establish connections via the radio unit 360 using the same radio technology (e.g., LTE or 5G NR).

[0071] 5. Extend device positioning for direct device-to-device connections

[0072] To support positioning in an operating scenario where only direct device-to-device communication is available, or in an operating scenario where direct device-to-device communication is preferred (e.g., a PC5-based only operating scenario), the following exemplary processes for performing target UE 110 position determination (e.g., positioning or ranging) are presented.

[0073] Figure 4 An exemplary positioning process initiated by the client UE 430 is involved. The presented process can be performed using only direct device-to-device communication (e.g., PC5-only operation). The described process is applicable to all coverage scenarios. The following types of UEs are participating in a positioning session (e.g., a sidelink positioning session): target UE 405, anchor UE 410, positioning server UE 420, and client UE 430.

[0074] In some embodiments, the target UE 405 may only support UE-assisted sidelink positioning methods, where UE-assisted sidelink positioning methods mean that the target UE 405 provides sidelink positioning and / or Uu positioning measurements for positioning calculations to another entity. The determined position may include absolute position information, relative position information, ranging information for distance, or ranging information for direction.

[0075] In a first step, the client UE 430 wants to know the current position of the target UE 405. The client UE 430 initiates a discovery process 440 (e.g., a sidelink discovery process) via the UE-to-UE interface 340 to discover other neighboring UEs. In one embodiment, the client UE 430 discovers only the positioning server UE 420 during this discovery process. In another embodiment, the client UE 430 may discover other UEs (e.g., the anchor UE 410 and / or the target UE 405) in addition to the positioning server UE 420 during this discovery process 440. Therefore, steps 450 to 465 can be skipped depending on which UEs have been discovered in the discovery step 440.

[0076] In step 445, the client UE 430 establishes a direct device-to-device communication connection (e.g., a sidelink connection) with the positioning server UE 420 via the UE-to-UE interface 340 (e.g., the PC5 interface), and sends a location request message to the positioning server UE 420 via the established connection. The location request message includes: a request to determine the location of the target UE 405. The location request message may be an MT-LR request message and may include an MT-LR type parameter. The MT-LR type parameter may support enabling the client UE 430 to request values for estimating the ranging distance and the ranging direction of the target UE 405. The ranging distance may refer to the distance of the target UE 405 to another entity (e.g., the anchor UE 410). The client UE 430 may request an estimate of the ranging distance by specifying the value "ranging distance estimation" for the MT-LR type parameter. The ranging direction may refer to the direction (e.g., an angle) between the target UE 405 and another entity (e.g., the anchor UE 410). The client UE 430 may request an estimate of the ranging direction by specifying the value "ranging direction estimation" for the MT-LR type parameter.

[0077] The location request message includes: one or more accuracy parameters indicating the target accuracy for location determination. The one or more accuracy parameters include at least one of the following: a relative accuracy parameter, an absolute accuracy parameter for distance determination (e.g., ranging distance determination), and an absolute accuracy parameter for direction determination (e.g., ranging direction determination). A location request including a relative accuracy parameter is related to a relative location estimation request. The one or more accuracy parameters may be quality of service (QoS) parameters (e.g., LCS QoS parameters) and may include at least one of the following: a horizontal relative accuracy parameter, a vertical relative accuracy parameter, a ranging distance absolute accuracy parameter, a ranging direction absolute accuracy parameter, a ranging distance relative accuracy parameter, and a ranging direction relative accuracy parameter. The horizontal relative accuracy parameter, the vertical relative accuracy parameter, the ranging distance absolute accuracy parameter, the ranging distance relative accuracy parameter, and the ranging direction relative accuracy parameter may have corresponding values specifying the respective accuracy in appropriate length units (e.g., meters, centimeters, inches, or feet). The ranging direction absolute accuracy parameter and the ranging direction relative accuracy parameter may have values specifying the respective accuracy in appropriate angle units (e.g., degrees or radians). The corresponding values of the accuracy parameters specify the accuracy (or maximum error) to be achieved in determining the location of the target UE 405.

[0078] If a relative position estimate or a ranging estimate (e.g., a ranging distance estimate or a ranging direction estimate) is requested, a reference position point may be needed, which can determine the relative position, the ranging distance, and / or the ranging direction. In this case, the position request message may include the position of the reference position point. The reference position point may be, for example, the position of the client UE 430 itself or the position of another known UE. An exemplary position request message may include the information shown in Table 3 and other information.

[0079]

[0080] Table 3

[0081] Assume that in step 440, the client 430 has not discovered the anchor UE 410. Then, the positioning server UE 420 initiates another discovery process 450 (e.g., a sidelink discovery process) via its UE-to-UE interface 340 to discover the target UE 405. In some embodiments, the positioning server UE 420 cannot directly discover the target UE 405. Instead, the positioning server UE 420 can discover the anchor UE 410. In other implementations, one or more anchor UEs 410 can be discovered. The number of (multiple) anchor UEs 410 that can be discovered may depend on the positioning method configured by the positioning server UE 420, such as SL-TDoA, SL-RTT variants (one-sided or two-sided RTT). In other embodiments, the target UE 405 is discovered in step 450. In this case, steps 455 to 465 can be skipped.

[0082] In step 455, the positioning server UE 420 establishes a direct device-to-device communication connection (e.g., a sidelink connection) with the anchor UE 410 via the UE-to-UE interface 340 (e.g., the PC5 interface), and sends a positioning request message (e.g., a sidelink positioning request message) to the anchor UE 410 via the established connection. The request message includes: a request to discover the target UE 405, which is used to determine the position of the target UE (e.g., sidelink positioning). The positioning request message may be a sidelink positioning protocol (SLPP) message, such as an SL positioning request message. In one implementation, the positioning request message contains a parameter "discovery type" with a value of "SL positioning". In another implementation, the request message further contains an embedded discovery message. Generally, the positioning request message (e.g., the sidelink positioning request message) can be used by the first (SL) UE (in this case, the positioning server UE 420) to request the second (SL) UE (in this case, the anchor UE 410) to discover the third (SL) UE (in this case, the target UE 405) for (SL) positioning.

[0083] In step 460, the anchor UE 410 initiates another discovery process (e.g., a sidelink discovery process) via its UE-to-UE interface 340 to discover the target UE 405. After the discovery, the anchor UE 410 establishes a direct device-to-device communication connection (e.g., a sidelink connection) with the target UE 405 via the UE-to-UE interface 340 (e.g., the PC5 interface).

[0084] In step 465, the anchor UE 410 sends a positioning response message (e.g., a sidelink positioning response message) to the positioning server UE 420 via the established direct device-to-device connection. The positioning response message includes an indication that the target UE 405 has been discovered. The positioning response message can be an SLPP message, e.g., an SL positioning response message. Generally, the positioning response message (e.g., a sidelink positioning request message) can be used by a first (SL) UE (in this case the anchor UE 410) to indicate to a second (SL) UE (in this case the positioning server UE 420) that a third (SL) UE (in this case the target UE 405) for (SL) positioning has been discovered.

[0085] Subsequently, in step 470, the positioning server UE 420, the anchor UE 410, and the target UE 405 perform a positioning process. These processes may include the transmission of SL positioning capabilities between the target UE 405 and the positioning server UE 420. Additionally, in some embodiments, the target UE 405 or the positioning server UE 420 may send an auxiliary data activation request to the anchor UE 410 via the established corresponding direct device-to-device connection. The auxiliary data activation request message may include a request to activate the transmission of auxiliary data by sending a positioning reference signal (PRS) to the target UE 405. The auxiliary data activation request may also include characteristics of the PRS (e.g., SL-PRS) transmission, such as start time and duration, frequency range (FR1 / FR2), resource bandwidth, comb size, resource repetition, mute configuration, power control parameters, etc. The auxiliary data activation request message may be an SLPP message, such as an SL auxiliary data activation request. Generally, the auxiliary data activation request is used by the first (SL) UE (in this case, the target UE 405 or the positioning server UE 420) to request the second (SL) UE (in this case, the anchor UE 410) to send an (SL-)PRS for (SL) positioning. The (SL-)PRS is a signal received by the target UE 405 (or in some cases, the auxiliary UE) from the anchor UE 410 via the established direct device-to-device connection and enables the target UE 405 (or the auxiliary UE) to perform measurements (e.g., AoD, ToF, TDOA, or RTT) based on the PRS (e.g., SL-PRS), and this measurement allows the calculation of the distance to the anchor UE 410 or the direction (e.g., angle) to the anchor UE 410. In some cases, according to the applied positioning method (e.g., the SL positioning method), multiple anchor UEs 410 participate in the positioning of the target UE 405 (e.g., the SL-TDOA positioning method requires multiple anchor UEs 410), and the target UE 405 may request and receive PRSs from each of the multiple anchor UEs 410 to perform measurements. Based on these measurements, the positioning server UE 420 determines the absolute or relative position of the target UE 405. In response to receiving the auxiliary data activation request, the anchor UE 410 selects a configuration type for the PRS, for example, according to its positioning capabilities and current load. The configuration type determines the characteristics (i.e., attributes) of the PRS. Then, the anchor UE 410 sends the PRS according to the selected configuration type. The target UE 405 receives the PRS via the direct device-to-device interface (e.g., the PC5 interface), performs measurements, and sends the measurement results to the positioning server UE 420, which can then determine the requested position of the target UE 405.

[0086] Depending on the coverage scenario (e.g., IC or PC scenario), the location determination can be additionally assisted by the PLMN network (e.g., by the LMF 140 or the RAN 120), or alternatively can be performed entirely by the PLMN location function (e.g., by the LMF 140).

[0087] After determining the location of the target UE 405, the positioning server UE 420 sends a location response message to the client UE 430 in step 475 via the established direct device-to-device connection. The location response message includes: the requested and determined location information for the target UE 405. The location response message can be an MT-LR response message and can include one or more accuracy parameters indicating the achieved accuracy for the location determination (e.g., included in the LCS MT-LR result parameters). The one or more accuracy parameters include at least one of the following: a relative accuracy parameter for distance determination (e.g., ranging distance determination), an absolute accuracy parameter, and an absolute accuracy parameter for direction determination (e.g., ranging direction determination). The one or more accuracy parameters can include at least one of the following: a horizontal relative accuracy parameter, a vertical relative accuracy parameter, a ranging distance absolute accuracy parameter, a ranging direction absolute accuracy parameter, a ranging distance relative accuracy parameter, and a ranging direction relative accuracy parameter. The horizontal relative accuracy parameter, the vertical relative accuracy parameter, the ranging distance absolute accuracy parameter, the ranging distance relative accuracy parameter, and the ranging direction relative accuracy parameter can have respective values specifying the corresponding accuracy in appropriate length units (e.g., meters, centimeters, inches, or feet). The ranging direction absolute accuracy parameter and the ranging direction relative accuracy parameter can have respective values specifying the corresponding accuracy in appropriate angular units (e.g., degrees or radians). The respective values of the accuracy parameters specify the accuracy (or maximum error) achieved in the location determination of the target UE 405.

[0088] In one embodiment, the various discovery processes performed in steps 440, 450, and 460 can be jointly performed in one step, with the aim of discovering the desired UEs (the positioning server UE 420, one or more anchor UEs 410, the target UE 405) at once. If no UEs can be discovered in the first attempt, the discovery process can also be repeated based on certain criteria (including the period of the discovery process, the number of times the discovery process is initiated, etc.).

[0089] Now turn to Figure 5, which shows the signal flow for an exemplary positioning process initiated by the target UE 502 for determining its own position based on direct device-to-device connections (e.g., SL connections) between multiple UEs. The presented process can be performed using only direct device-to-device communication (e.g., only PC5 operation). The described process is applicable to all coverage scenarios. The following types of UEs are participating in the positioning session (e.g., sidelink positioning session): the target UE 502 (which also acts as the client UE), the anchor UE 504, and the positioning server UE 506.

[0090] In some embodiments, the target UE 502 may only support the UE-assisted SL positioning method, where the UE-assisted SL positioning method means that the target UE 502 provides sidelink positioning and / or Uu positioning measurements for positioning calculations to another entity. The determined position may include absolute position information, relative position information, ranging information for distance, or ranging information for direction.

[0091] In the first step, the target UE 502 wants to know its own current position. The target UE 502 initiates a discovery process 510 (e.g., sidelink discovery process) via its UE-to-UE interface 340 to discover other neighboring UEs. In one embodiment, the target UE 502 only discovers the anchor UE 504. In another embodiment, the target UE 502 may discover other UEs (e.g., additional anchor UE 504 and / or positioning server UE 506) in addition to the anchor UE 504 in the discovery process 510. Therefore, steps 515 to 525 can be skipped depending on whether the positioning server UE 506 has been discovered in the first discovery process of step 510.

[0092] After the anchor UE 504 is discovered, the target UE 502 establishes a direct device-to-device communication connection (e.g., sidelink connection) with the anchor UE 504 via the UE-to-UE interface 340 (e.g., PC5 interface). Assuming that the target UE 502 has not discovered the positioning server UE 506 in step 510, in step 515, the target UE 502 sends a positioning request message (e.g., sidelink positioning request message) to the anchor UE 504 via the established connection. The request message includes: a request to discover the positioning server UE 506, which is used to determine the location of the target UE. The positioning request message may be a sidelink positioning protocol (SLPP) message, such as an SL positioning request message. In one implementation, the positioning request message contains a parameter "discovery type" with a value of "SL positioning". In another implementation, the request message further contains an embedded discovery message. Generally, the positioning request message (e.g., sidelink positioning request message) can be used by the first (SL) UE (in this case the target UE 502) to request the second (SL) UE (in this case the anchor UE 504) to discover the third (SL) UE (in this case the positioning server UE 506) for (SL) positioning.

[0093] In step 520, the anchor UE 504 initiates another discovery process (e.g., sidelink discovery process) via its UE-to-UE interface 340 to discover the positioning server UE 506. After the positioning server UE 506 is discovered, the anchor UE 504 establishes a direct device-to-device communication connection (e.g., sidelink connection) with the positioning server UE 506 via its UE-to-UE interface 340 (e.g., PC5 interface).

[0094] In step 525, the anchor UE 504 sends a positioning response message (e.g., sidelink positioning response message) to the target UE 502, and the positioning response message includes: an indication that the positioning server UE 506 has been discovered. The positioning response message may be an SLPP message, such as an SL positioning response message. Generally, the positioning response message (e.g., sidelink positioning request message) can be used by the first (SL) UE (in this case the anchor UE 504) to indicate to the second (SL) UE (in this case the target UE 502) that the third (SL) UE (in this case the positioning server UE 506) for positioning (e.g., SL positioning) has been discovered.

[0095] In step 530, the target UE 502 sends a location request message to the anchor UE 504 via a previously established connection. The location request message includes: a request to determine the location of the target UE 502 itself. The location request message can be a MO-LR request message and can include a MO-LR type parameter. The MO-LR type parameter can support values that enable the target UE 502 to request an estimated ranging distance and a ranging direction of the target UE 502. The ranging distance can refer to the distance from the target UE 502 to another entity (e.g., the anchor UE 504). The target UE 502 can request an estimate of the ranging distance by specifying the value "ranging distance estimate" for the MO-LR type parameter. The ranging direction can refer to the direction (e.g., angle) between the target UE 502 and another entity (e.g., the anchor UE 504). The target UE 502 can request an estimate of the ranging direction by specifying the value "ranging direction estimate" for the MO-LR type parameter.

[0096] The location request message includes: one or more accuracy parameters indicating the target accuracy for location determination. The one or more accuracy parameters include at least one of the following: a relative accuracy parameter, an absolute accuracy parameter for distance determination (e.g., ranging distance determination), and an absolute accuracy parameter for direction determination (e.g., ranging direction determination). A location request including a relative accuracy parameter is related to a relative location estimation request. The one or more accuracy parameters can be quality of service (QoS) parameters (e.g., LCS QoS parameters) and can include at least one of the following: a horizontal relative accuracy parameter, a vertical relative accuracy parameter, a ranging distance absolute accuracy parameter, a ranging direction absolute accuracy parameter, a ranging distance relative accuracy parameter, and a ranging direction relative accuracy parameter. The horizontal relative accuracy parameter, the vertical relative accuracy parameter, the ranging distance absolute accuracy parameter, the ranging distance relative accuracy parameter, and the ranging direction relative accuracy parameter can have corresponding values specifying the respective accuracy in appropriate length units (e.g., meters, centimeters, inches, or feet). The ranging direction absolute accuracy parameter and the ranging direction relative accuracy parameter can have values specifying the respective accuracy in appropriate angular units (e.g., degrees or radians). The corresponding values of the accuracy parameters specify the accuracy (or maximum error) to be achieved in the location determination of the target UE 502.

[0097] If a relative location estimate or a ranging estimate (e.g., ranging distance estimate or ranging direction estimate) is requested, a reference location point is required, which can determine the relative location, the ranging distance, and / or the ranging direction. In this case, the location request message can contain the location of the reference location point. The reference location point can be, for example, the location of the anchor UE 504 or the location of another known UE.

[0098] An exemplary location request message can include the information shown in Table 4 and other information.

[0099]

[0100] Table 4

[0101] In step 535, the anchor UE 504 forwards a request message to the positioning server UE 506.

[0102] Subsequently, in step 540, the positioning server UE 506, the anchor UE 504, and the target UE 502 perform a positioning process. These processes may include the transmission of SL positioning capabilities between the target UE 502 and the positioning server UE 506. Additionally, in some embodiments, the target UE 502 or the positioning server UE 506 may send an auxiliary data activation request to the anchor UE 504 via the established respective direct device-to-device connection. The auxiliary data activation request message may include a request to activate the transmission of auxiliary data by sending a positioning reference signal (PRS) to the target UE 502. The auxiliary data activation request may also include characteristics of the PRS (e.g., SL-PRS) transmission, such as start time and duration, frequency range (FR1 / FR2), resource bandwidth, comb size, resource repetition, mute configuration, power control parameters, etc. The auxiliary data activation request message may be an SLPP message, such as an SL auxiliary data activation request. Generally, the auxiliary data activation request is used by the first (SL) UE (in this case, the target UE 502 or the positioning server UE 506) to request the second (SL) UE (in this case, the anchor UE 504) to send (SL-)PRS for (SL) positioning. The (SL-)PRS is a signal received by the target UE 502 (or in some cases by an auxiliary UE) from the anchor UE 504 via the established direct device-to-device connection and enables the target UE 502 (or the auxiliary UE) to perform measurements (e.g., AoD, ToF, TDOA, or RTT) that allow the calculation of the distance to the anchor UE 504 or the direction (e.g., angle) to the anchor UE 504. In some cases, depending on the applied positioning method (e.g., SL positioning method), multiple anchor UEs 504 participate in the target UE positioning (e.g., the SL-TDOA positioning method requires multiple anchor UEs 504), and the target UE 502 may request and receive PRS from each of the multiple anchor UEs 504 to perform measurements. Based on these measurements, the positioning server UE 506 determines the absolute or relative position of the target UE 502. In response to receiving the auxiliary data activation request, the anchor UE 504 selects a configuration type for the PRS, for example, according to its positioning capabilities and current load. The configuration type determines the characteristics (i.e., attributes) of the PRS. Then, the anchor UE 504 sends the PRS according to the selected configuration type. The target UE 502 receives the PRS via the direct device-to-device interface, performs measurements, and sends the measurement results to the positioning server UE 506, which can then determine the requested position of the target UE 502.

[0103] Depending on the coverage situation (e.g., IC or PC scenario), location determination can be additionally assisted by a PLMN network (e.g., by the LMF 140 or the RAN 120), or alternatively can be performed entirely by a PLMN location function (e.g., by the LMF 140).

[0104] After determining the location of the target UE 502, the positioning server UE 506 sends a location response message to the anchor UE 504 via the established direct device-to-device connection in step 545. The location response message includes: the requested and determined location information of the target UE 502. The location response message can be a MO-LR response message and can include one or more accuracy parameters indicating the achieved accuracy for location determination (e.g., included in the LCS MO-LR result parameter). The one or more accuracy parameters include at least one of the following: a relative accuracy parameter for distance determination (e.g., ranging distance determination), an absolute accuracy parameter, and an absolute accuracy parameter for direction determination (e.g., ranging direction determination). The one or more accuracy parameters can include at least one of the following: a horizontal relative accuracy parameter, a vertical relative accuracy parameter, a ranging distance absolute accuracy parameter, a ranging direction absolute accuracy parameter, a ranging distance relative accuracy parameter, and a ranging direction relative accuracy parameter. The horizontal relative accuracy parameter, the vertical relative accuracy parameter, the ranging distance absolute accuracy parameter, the ranging distance relative accuracy parameter, and the ranging direction relative accuracy parameter can have corresponding values specifying the respective accuracy in appropriate length units (e.g., meters, centimeters, inches, or feet). The ranging direction absolute accuracy parameter and the ranging direction relative accuracy parameter can have values specifying the respective accuracy in appropriate angular units (e.g., degrees or radians). The corresponding values of the accuracy parameters specify the accuracy (or maximum error) achieved in the location determination of the target UE 502. In step 550, the anchor UE 504 forwards the response message to the target UE 502.

[0105] Figure 6Shows the signal flow of an exemplary positioning process initiated by the target UE 604. The presented process can be performed using only direct device-to-device communication (e.g., only PC5 operation). The described process is applicable to all coverage scenarios. The following types of UEs are participating in the positioning session (e.g., sidelink positioning session): the target UE 604 and the anchor UE 608. The target UE 604 also acts as a positioning server UE and a client UE. In some embodiments, the target UE 604 can support UE-assisted and UE-based SL positioning methods, where the UE-assisted SL positioning method means that the target UE 604 provides SL positioning and / or Uu positioning measurements for positioning calculations to another entity, while the UE-based SL positioning method means that the target UE 604 performs positioning calculations internally (acts as a positioning server UE). The determined location can include absolute location information, relative location information, ranging information for distance, or ranging information for direction.

[0106] In a first step, the target UE 604 wants to know its own current location. Since the target UE 604 also acts as a positioning server UE (e.g., SL positioning server UE), the target UE positioning only needs to support one or more anchor UEs 608. The target UE 604 initiates a discovery process 610 (e.g., sidelink discovery process) via its UE-to-UE interface 340 to discover one or more neighboring anchor UEs 608.

[0107] After the anchor UE 608 is discovered, the target UE 604 establishes a direct device-to-device communication connection (e.g., sidelink connection) with one or more anchor UEs 608 via its UE-to-UE interface 340 (e.g., PC5 interface). In step 620, the target UE 604 sends an assistance data activation request to the anchor UE 608 via the established direct device-to-device connection. The assistance data activation request message includes: a request to activate the transmission of assistance data by sending a positioning reference signal (PRS) to the target UE 604. The assistance data activation request may also include characteristics of the PRS (e.g., SL-PRS) transmission, such as start time and duration, frequency range (FR1 / FR2), resource bandwidth, comb size, resource repetition, mute configuration, power control parameters, etc. The assistance data activation request message may be an SLPP message, such as an SL assistance data activation request. Generally, the assistance data activation request is used by the first (SL) UE (in this case the target UE 604) to request the second (SL) UE (in this case the anchor UE 608) to send an (SL-)PRS for (SL) positioning. In response to receiving the assistance data activation request, the anchor UE 608 selects a configuration type for the PRS, for example, according to its positioning capabilities and current load. The configuration type determines the characteristics (i.e., attributes) of the PRS. In some implementations, the request message may be conveyed using the SLPP RequestAssistanceData message.

[0108] In step 630, the data activation response may optionally be sent from the anchor UE 608 to the target UE 604 via the established connection. The response message may include the PRS configuration type selected by the anchor UE 608 according to its (SL) positioning capabilities and / or current load, for example. In some implementations, the response message may be conveyed using the SLPP ProvideAssistanceData message. In another implementation, the SL assistance data may be provided to the target UE 604 in an unsolicited manner.

[0109] In step 640, the anchor UE 608 sends a PRS (e.g., SL-PRS) to the target UE 604 via the established direct device-to-device connection (e.g., connection 240) according to the selected configuration type. The PRS is configured such that the target UE 604 can perform measurements based on the PRS (e.g., AoD, ToF, TDOA, or RTT), which allows the calculation of the distance to the anchor UE 608 or the direction (e.g., angle) to the anchor UE 608.

[0110] In step 650, the target UE 604 receives PRS (e.g., SL-PRS) from the anchor UE 608 and performs measurements based on the PRS (e.g., AoD, ToF, TDOA, or RTT), which allows calculating the distance to the anchor UE 608 or the direction (e.g., angle) to the anchor UE 608. In some cases, according to the applied positioning method (e.g., SL positioning method), multiple anchor UEs 608 are involved in target UE positioning (e.g., the SL-TDOA positioning method requires multiple anchor UEs 608), and the target UE 604 can request and receive PRS from each of the multiple anchor UEs 608 to perform measurements. The target UE 604 acting as a positioning server UE can process the measurements to determine the absolute or relative position of the target UE 604.

[0111] Now turning to an exemplary positioning process initiated by the client UE 706, as Figure 7 shown. The presented process can be performed using only direct device-to-device communication (e.g., only PC5 operation). The described process is applicable to all coverage scenarios. The following types of UEs are participating in a positioning session (e.g., a sidelink positioning session): the target UE 702, the anchor UE 704, and the client UE 706. The target UE 702 also acts as a positioning server UE. In some embodiments, the target UE 702 can support UE-assisted and UE-based SL positioning methods, where the UE-assisted SL positioning method means that the target UE 702 provides SL positioning and / or Uu positioning measurements for positioning calculations to another entity, while the UE-based SL positioning method means that the target UE 702 performs positioning calculations internally (acting as a positioning server UE). The determined position can include absolute position information, relative position information, ranging information for distance, or ranging information for direction.

[0112] In a first step, the client UE 706 wants to know the current position of the target UE 702. The client UE 706 initiates a discovery process (e.g., an SL discovery process) 710 to discover other neighboring UEs. The remaining process assumes that the client UE 706 can discover the target UE 702 and the anchor UE 704. However, as described with respect to Figure 4 what is described, in some cases, the client UE 706 may not discover the target UE 702 during the discovery process because the target UE 702 may, for example, not be within the neighboring range for direct device-to-device connections. In such cases, additional discovery steps (e.g., according to steps 455, 460, and 465 or 515, 520, and 525) may be required to discover all the UEs needed to perform the positioning process, especially to discover the target UE 702.

[0113] In step 720, the client UE 706 establishes a direct device-to-device communication connection (e.g., sidelink connection) with the target UE 702 acting as a positioning server UE via the UE-to-UE interface 340 (e.g., PC5 interface), and sends a location request message to the target UE 702 via the established connection. The location request message includes: a request to determine the location of the target UE 702. The location request message has the same attributes as the location request message sent between the client UE 430 and the positioning server UE 420 in step 445. In particular, the location request message may include accuracy parameters and may be an MT-LR request as described in step 445 of reference Figure 4 as described in step 445.

[0114] In step 730, the target UE 702 acting as a positioning server UE establishes a direct device-to-device communication connection (e.g., sidelink connection) with the anchor UE 704 via its UE-to-UE interface 340 (e.g., PC5 interface), and sends an assistance data activation request to the anchor UE 704 via the established direct device-to-device connection. The assistance data activation request message includes: a request to activate the transmission of assistance data by sending a positioning reference signal (PRS) to the target UE 702. The assistance data activation request may also include characteristics of the PRS (e.g., SL-PRS) transmission, such as start time and duration, frequency range (FR1 / FR2), resource bandwidth, comb size, resource repetition, mute configuration, power control parameters, etc. The assistance data activation request message may be an SLPP message, such as an SL assistance data activation request. Generally, the assistance data activation request is used by the first (SL) UE (in this case, the target UE 702 acting as a positioning server UE) to request the second (SL) UE (in this case, the anchor UE 704) to send (SL-)PRS for (SL) positioning. In response to receiving the assistance data activation request, the anchor UE 704 selects a configuration type for the PRS, for example, according to its positioning capabilities and / or current load. The configuration type determines the characteristics (i.e., attributes) of the PRS. In some implementations, the request message may be conveyed using the SLPP RequestAssistanceData message.

[0115] In step 740, the data activation response may optionally be sent from the anchor UE 704 to the target UE 702 via the established connection. The response message may include the PRS configuration type selected by the anchor UE 704. In some implementations, the response message may be conveyed using the SLPP ProvideAssistanceData message. In another implementation, the SL assistance data may be provided to the target UE 702 in an unsolicited manner.

[0116] In step 750, the anchor UE 704 sends a PRS (e.g., SL-PRS) to the target UE 702 via the established direct device-to-device connection (e.g., connection 240) according to the selected configuration type. The PRS is configured such that the target UE 702 can perform measurements based on the PRS (e.g., AoD, ToF, TDOA, or RTT), and the measurements allow the calculation of the distance to the anchor UE 704 or the direction (e.g., angle) to the anchor UE 704.

[0117] In step 760, the target UE 702 receives the PRS (e.g., SL-PRS) from the anchor UE 704 via the established direct device-to-device connection and performs measurements based on the PRS (e.g., AoD, ToF, TDOA, or RTT), and the measurements allow the calculation of the distance to the anchor UE 704 or the direction (e.g., angle) to the anchor UE 704. In some cases, according to the applied positioning method (e.g., SL positioning method), multiple anchor UEs 704 participate in the positioning of the target UE 702 (e.g., the SL-TDOA positioning method requires multiple anchor UEs 704), and the target UE 702 can request and receive PRSs from each of the multiple anchor UEs 704 to perform measurements. The target UE 702 acting as a positioning server UE can process the measurements to determine the absolute or relative position of the target UE 702.

[0118] After determining the position of the target UE 702, in step 770, the target UE 702 acting as a positioning server UE sends a position response message to the client UE 706 via the established direct device-to-device connection. Note that in the case where the client UE 706 cannot detect the target UE 702 in the first discovery step, the client UE 706 may not have a direct connection to the target UE 702. In this case, the anchor UE 704 may have discovered the target UE 702 in the second discovery step (e.g., according to Figure 4 455, 460, and 465), and may have established a direct device-to-device connection to the target UE 702. In this case, the target UE 702 acting as a positioning server UE can send a position response message to the anchor UE 704 via the established direct device-to-device connection, and the anchor UE 704 can forward the position response message to the client UE 706 via its direct device-to-device connection.

[0119] In any case, the position response message includes: the requested and determined position information of the target UE 702. In addition, the position response message can have the same attributes as the position response message in step 475. In particular, as regarding Figure 4As described in more detail in step 475, the location response message can be an MT-LR response message and can include one or more accuracy parameters (e.g., included in the LCS MT-LR result parameter) indicating the implementation accuracy for location determination.

[0120] The methods and apparatuses presented in the above embodiments achieve efficient determination of the relative or absolute location of a mobile telecommunications network device (i.e., a UE, such as target UE 702) without relying on network location services (such as LMF 140). Thus, the described embodiments support positioning (e.g., SL positioning) in all communication scenarios (i.e., IC, PC, and OOC scenarios), including operation scenarios based only on PC5. Additionally, various types of UEs that support direct device-to-device connections and participate in a positioning session (e.g., an SL positioning session) can be supported (e.g., SL UEs support SL connections via the PC5 interface). Even in one of the following situations, the described embodiments support stable positioning (e.g., SL positioning): the positioning server UE (e.g., SL positioning server UE) is out of coverage, an LMF 140 without SL positioning and / or ranging capabilities is available, the LMF 140 decides for the positioning server UE (e.g., SL positioning server UE) to perform result calculation, the positioning server UE (e.g., SL positioning server UE) decides on its own to perform only PC5 positioning and / or ranging, and / or the positioning server UE (e.g., SL positioning server UE) has no LPP capabilities and only SLPP capabilities. It should also be noted that although the described embodiments achieve target UE positioning independent of network-based location or positioning services (such as LMF 140), when all UEs (IC scenario) or some UEs (PC scenario) participating in the described embodiments (e.g., target UE 405, 502, 604, 702, anchor UE 410, 504, 608, 704, positioning server UE 420, 506, and / or client UE 430, 706) are within the coverage of an NG-RAN node (e.g., NG-eNB or gNB), the target UE location determination can additionally be supported by network location services (e.g., LM 140).

[0121] In Figures 4 to 7In the above description, target UEs 405, 502, 604, 702 correspond to each other because they all conform to the role of the target UE defined in Section 4. This also applies to anchor UEs 410, 504, 608, and 704 in terms of their role as anchor UEs. Similarly, positioning server UEs 420, 506 correspond to each other. Although they have combined functions, in terms of their functions as positioning server UEs defined in Section 4, UEs 604 and 702 correspond to each other and correspond to positioning server UEs 420, 506. Finally, client UEs 430, 706 with combined functions and target UEs 502 and 702 correspond to each other in terms of their functions as client UEs. It should also be noted that all of the above UEs can be implemented according to the mobile telecommunications network device 300. In this specification, the terms mobile telecommunications network device and communication device can be used interchangeably. Additionally, in terms of Figure 6 and Figure 7 the combined functions implemented in target UEs 604 and 702 of the described process can be implemented as separate UEs with only one of the combined roles. Thus, the functions performed by Figure 6 target UE 604 can alternatively be implemented by a target UE and a separate client UE. Similarly, the functions performed by Figure 7 target UE 702 can alternatively be implemented by three separate UEs: a target UE, a client UE, and a positioning server UE.

[0122] The above features can be implemented as computer-implemented methods by different mobile telecommunications network devices in a mobile telecommunications network. Additionally, the computer-implemented methods can be implemented as instructions on a computer-readable medium. Thus, this specification relates to computer-implemented methods for performing target UE positioning, as well as computer-readable media and mobile telecommunications network devices for implementing these methods. All of the above network functions (e.g., AMF 130 or LMF 140) can be computer functions running on independent computer servers implementing the corresponding functions, or different network functions can share one or more computer servers.

[0123] The embodiments presented in this document should not be construed as being limited to the specific combinations of features described as being performed by hardware and / or software entities. In particular, other possible embodiments may include any combination of features from the described embodiments. Additionally, features described in the context of a particular embodiment may also be included in other embodiments without being explicitly presented. Embodiments may include more or fewer features than those described. Moreover, software and hardware entities may perform more or fewer features than those described in some embodiments. A software or hardware entity may also perform features described in the context of other software or hardware entities. Additionally, steps described in a particular order in the context of a method may be performed in any other reasonable order. It should be understood that this specification includes all embodiments resulting from alternative combinations of these features and entities.

[0124] Although the present invention has been described with respect to physical embodiments constructed in accordance with the present invention, those skilled in the art will appreciate that various modifications, variations, and improvements to the present invention can be made in accordance with the teachings above and within the scope of the appended claims without departing from the spirit and intended scope of the present disclosure. Additionally, in order not to unduly obscure the invention described herein, those areas that are familiar to those of ordinary skill in the art have not been described herein. Therefore, it should be understood that the present invention is not limited by the specific illustrative embodiments, but only by the scope of the appended claims.

[0125] 6. List of Abbreviations

[0126] 3GPP Third Generation Partnership Project

[0127] 5GS 5G System

[0128] A-GNSS Assisted GNSS AMF Access and Mobility Management Function

[0129] AoA Angle of Arrival

[0130] AoD Angle of Departure

[0131] CM Connection Management

[0132] DL Downlink

[0133] DL TDOA Downlink Time Difference of Arrival

[0134] E-CID Enhanced Cell ID

[0135] FR Frequency Range

[0136] GMLC Gateway Mobile Location Center

[0137] GNSS Global Navigation Satellite System

[0138] GPSI General Public Subscription Identifier

[0139] HW Hardware

[0140] IC In Coverage

[0141] IIoT Industrial IoT

[0142] IoT Internet of Things

[0143] KPI Key Performance Indicator

[0144] LCS Location Service

[0145] LMF Location Management Function

[0146] LPP LTE Positioning Protocol

[0147] LTE Long-Term Evolution MO-LR Mobile Originated Location Request MT-LR Mobile Terminated Location Request Multi RTT Round Trip Time Multi NAS Non-Access Stratum NG-RAN Next Generation RAN NI-LR Network Induced Location Request NR New Radio NRPPa NR Positioning Protocol A OOC Out of Coverage PC Partial Coverage PDU Protocol Data Unit PHY Physical Layer PLMN Public Land Mobile Network PPP Precise Point Positioning ProSe Proximity-based Services PRS Positioning Reference Signal PSAP Public Safety Answering Point QoS Quality of Service RAN Radio Access Network RAT Radio Access Technology RRC Radio Resource Control RSU Road Side Unit RTK Real-Time Kinematic SL Sidelink SLPP Sidelink Positioning Protocol SUPI Subscription Permanent Identifier SW Software TDOA Time Difference of Arrival

[0148] Time of Flight (ToF)

[0149] Time to First Fix (TTFF)

[0150] User Equipment (UE)

[0151] Uplink (UL)

[0152] Vehicle-to-Everything (V2X)

[0153] Work Item Description (WID)

Claims

1. A mobile telecommunications network device includes a first interface configured to provide communication with a mobile telecommunications network via a radio unit, and a second interface configured to provide direct device-to-device communication within a proximity range via the radio unit, the device comprising: One or more processors configured to execute computer-readable instructions for implementing determination of a target communication device location, the instructions causing the one or more processors to: Establish a direct device-to-device connection to a communication device within the proximity range via the second interface; Send a location request message to the communication device via the established connection, the location request message including: a request to determine the location of the target communication device, and one or more accuracy parameters indicating a target accuracy for the location determination, wherein the one or more accuracy parameters include at least one of the following: a relative accuracy parameter for distance determination, an absolute accuracy parameter, and an absolute accuracy parameter for direction determination; and Receive a location response message from the communication device via the established connection, the location response message including: data indicating the location of the target communication device determined according to the one or more accuracy parameters.

2. The mobile telecommunications network device according to claim 1, wherein the mobile telecommunications network device is the target communication device.

3. The mobile telecommunications network device according to claim 2, wherein the communication device is an anchor UE configured to support the determination of the location of the target communication device, and wherein the instructions further cause the one or more processors to: Send a positioning request message to the anchor UE via the established connection, the positioning request message including: Discover a request for another communication device within the proximity range, wherein the positioning request message is configured to cause the anchor UE to discover the other communication device according to the received positioning request message; And Receive a positioning response message from the anchor UE via the established connection indicating that the other communication device has been discovered.

4. The mobile telecommunications network device according to claim 2 or 3, wherein the communication device is an anchor UE configured to support the determination of the location of the target communication device, and wherein the instructions further cause the one or more processors to: Receive a positioning reference signal from the anchor UE via the established connection; and Perform measurements based on the positioning reference signal for determining the location of the target communication device.

5. The mobile telecommunications network device according to claim 1, wherein the mobile telecommunications network device is different from the target communication device.

6. The mobile telecommunications network device according to any one of the preceding claims, wherein the request to determine the location of the target communication device includes at least one of the following: a request to determine a ranging distance estimate for the target communication device, and a request to determine a ranging direction estimate for the target communication device.

7. The mobile telecommunications network device according to any one of the preceding claims, wherein the communication device is a positioning server UE configured to determine the location of the target communication device, and wherein the location request message is configured to cause the communication device to determine the location of the target communication device according to the one or more accuracy parameters.

8. The mobile telecommunications network device according to any one of the preceding claims, wherein the one or more accuracy parameters are quality of service (QoS) parameters and include at least one of the following: horizontal relative accuracy parameter, vertical relative accuracy parameter, ranging distance absolute accuracy parameter, ranging distance relative accuracy parameter, ranging direction absolute accuracy parameter, and ranging direction relative accuracy parameter.

9. The mobile telecommunications network device according to any one of the preceding claims, wherein the one or more accuracy parameters include relative accuracy parameters, and wherein the request for determining the location of the target communication device comprises: A request to determine the location of the target communication device relative to a reference location, and wherein the location request message further includes data indicating the reference location.

10. A mobile telecommunications network device, comprising a first interface configured to provide communication with a mobile telecommunications network via a radio unit, and a second interface configured to provide direct device-to-device communication within a proximity range via the radio unit, the device comprising: One or more processors configured to execute computer-readable instructions for implementing discovery of a communication device for device location determination, the instructions causing the one or more processors to: Establish a direct device-to-device connection to a first communication device within the proximity range via the second interface; Receive, via the established connection, a location request message from the first communication device, the location request message including: a request to discover a second communication device within the proximity range; Discover the second communication device according to the received location request message; and Send, via the established connection, a location response message to the first communication device, the location response message indicating that the second communication device has been discovered.

11. The mobile telecommunications network device according to claim 10, wherein the instructions further cause the one or more processors to: Establish another direct device-to-device connection to the second communication device via the second interface; and Collaborating with the first communication device and the second communication device to perform position determination for the first communication device or the second communication device, wherein performing the position determination includes: Exchange messages with the first communication device and the second communication device via the direct device-to-device connections to the first communication device and the second communication device.

12. The mobile telecommunications network device according to any one of claims 10 or 11, wherein the first communication device is a positioning server UE configured to determine the location of a target communication device, the target communication device being the second communication device.

13. The mobile telecommunications network device according to any one of claims 10 or 11, wherein the second communication device is a positioning server UE configured to determine the location of a target communication device, the target communication device being the first communication device.

14. The mobile telecommunications network device according to any one of claims 12 or 13, wherein the instructions further cause the one or more processors to: Receive an auxiliary data activation request message from the positioning server UE, the auxiliary data activation request message including: A request to activate the transmission of auxiliary data by sending a positioning reference signal to the target communication device; Select a configuration type for the positioning reference signal, the configuration type specifying the attributes of the positioning reference signal; And Send the positioning reference signal to the target communication device according to the selected configuration type, wherein the positioning reference signal is configured such that the target communication device can perform measurements based on the positioning reference signal, and the measurements are used to enable the positioning server UE to determine the position of the target communication device.

15. The mobile telecommunications network device according to claim 13, wherein the instructions cause the one or more processors to: Receiving a location request message from the target communication device, the location request message including: Determine a request for the position of the target communication device and one or more accuracy parameters indicating a target accuracy for the position determination, wherein the one or more accuracy parameters include at least one of the following: a relative accuracy parameter for distance determination, an absolute accuracy parameter, and an absolute accuracy parameter for direction determination; Send the position request message to the positioning server UE to cause the positioning server UE to determine the position of the target communication device determined according to the one or more accuracy parameters; Receive a position response message from the positioning server UE, the position response message including: data indicating the position of the target communication device; And Send the position response message to the target communication device.

16. A mobile telecommunications network device, comprising a first interface configured to provide communication with a mobile telecommunications network via a radio unit and a second interface configured to provide direct device-to-device communication within a proximity range via the radio unit, the device comprising: One or more processors configured to execute computer-readable instructions for assisting in determining the position of a target communication device, the instructions causing the one or more processors to: Establish a direct device-to-device connection to a communication device within the proximity range via the second interface; And Send an auxiliary data activation request message to the communication device via the established connection, the auxiliary data activation request message including: a request to activate the transmission of auxiliary data by sending a positioning reference signal to the target communication device, wherein the auxiliary data activation request message is configured such that the communication device: Select a configuration type for the positioning reference signal, the configuration type specifying the attributes of the positioning reference signal; And Send the positioning reference signal to the target communication device via the direct device-to-device connection according to the selected configuration type, wherein the positioning reference signal is configured such that the target communication device can perform measurements based on the positioning reference signal, and the measurements are used to determine the position of the target communication device.

17. The mobile telecommunications network device according to claim 16, wherein the instructions further cause the one or more processors to: receive an auxiliary data activation response message from the communication device via the established connection, the auxiliary data activation response message including: The selected configuration type of the positioning reference signal.

18. The mobile telecommunications network device according to claim 16 or 17, wherein the instructions further cause the one or more processors to: Receiving a location request message from the communication device via the established connection, the location request message including: A request for determining the location of the target communication device, and one or more accuracy parameters indicating a target accuracy for the location determination, wherein the one or more accuracy parameters include at least one of the following: a relative accuracy parameter for distance determination, an absolute accuracy parameter, and an absolute accuracy parameter for direction determination; Determine the location of the target communication device according to the one or more accuracy parameters; And Send a location response message to the communication device via the established connection, the location response message including: data indicating the location of the target communication device.

19. The mobile telecommunications network device according to any one of claims 16 to 18, wherein the device is further configured to determine the location of the target communication device.

20. The mobile telecommunications network device according to any one of claims 16 to 19, wherein the device is the target communication device, and the instructions further cause the one or more processors to: Receive the target positioning reference signal from the communication device via the established connection according to the selected configuration type; Perform measurements based on the positioning reference signal, the measurements being used to determine the location of the target communication device.

Images