Device-to-device assisted positioning in wireless cellular technology

Abstract

Embodiments of the present disclosure relate to device-to-device assisted positioning in wireless cellular technology. A location of a user equipment (UE) can be determined based on information communicated via direct UE-to-UE communication to obtain more measurements of location metrics that can be used to determine a relative or absolute location of the UE. In one implementation, a user equipment can receive a positioning reference signal over a direct connection with a second UE from which timing information related to a distance between the UE and the second UE can be derived; determine a first location metric based on the positioning reference signal, the first location metric related to a location of the UE relative to the second UE; and determine a location of the UE based at least in part on the location metric.

Description

[0001] This application is a divisional application of the invention patent application filed on August 21, 2015, with application number 201580044057.4 and invention title "Device-to-Device Assisted Positioning in Wireless Cellular Technology".

[0002] Related applications

[0003] This application claims the benefit of U.S. Provisional Patent Application No. 62 / 055,474, filed on September 25, 2014, which is incorporated herein by reference in its entirety. Background Technology

[0004] Wireless networks provide network connectivity to mobile communication devices such as smartphones via wireless interfaces. Location services, which determine the location of communication devices, can be a desired feature within a wireless network. For example, location determination can be important when providing navigation services, emergency services, or other services that can be offered to mobile devices.

[0005] Accurately determining the location of mobile devices in various situations and environments can be challenging. Specifications published by the 3rd Generation Partnership Project (3GPP) describe three main device location services: Enhanced Cell Identification (ECID); Assisted Global Navigation Satellite System (ANA); and Downlink Observed Time Difference of Arrival (OTDOA). However, achieving accurate location using wireless technologies faces numerous challenges that can lead to coarse location accuracy in many scenarios. These challenges may include poor performance in indoor environments due to high penetration loss and the non-line-of-sight (NLOS) nature of signal propagation from the location signal source. Attached Figure Description

[0006] Embodiments of the invention will be readily understood from the accompanying drawings and the following detailed description. For ease of explanation, similar reference numerals may refer to similar structural elements. Embodiments of the invention are shown in the accompanying drawings by way of example rather than limitation.

[0007] Figure 1 This is an overview diagram illustrating an example of the implementation described in this article;

[0008] Figure 2 This is a diagram of an example environment in which the systems and / or methods described in this paper can be implemented;

[0009] Figure 3 This is a conceptual diagram illustrating the use of an anchor UE to determine the location of a target UE;

[0010] Figure 4 This is a conceptual diagram illustrating the location determination of a target UE using a non-anchored UE, referred to herein as an auxiliary UE;

[0011] Figure 5 This is a conceptual diagram illustrating the use of a combination of anchor UE and auxiliary UE to determine the location of a target UE;

[0012] Figure 6 This is a flowchart illustrating an example of a process that can be used to determine the location of a target UE when a sidelink channel between the target UE and one or more other UEs is available.

[0013] Figure 7 This is a flowchart illustrating an example of a process that can be used to determine the location of a target UE based on uplink transmissions from the target UE; and

[0014] Figure 8 This is a diagram of example components of the device. Detailed Implementation

[0015] The following detailed description refers to the accompanying drawings. The same reference numerals may identify the same or similar elements in different figures. It should be understood that other embodiments may be adopted, and structural or logical variations may be made without departing from the scope of this disclosure. Therefore, the following detailed description should not be construed as limiting, and the scope of embodiments according to the present invention is defined by the appended claims and their equivalents.

[0016] The techniques described in this paper can determine the location of a mobile device based on information transmitted via device-to-device (D2D) communication to obtain additional location metrics, which can be used to determine the relative or absolute location of the mobile device. In some implementations, more location metrics can be combined with metrics obtained through conventional positioning techniques to determine the device location more accurately.

[0017] In one implementation, a user equipment (UE) may include processing circuitry for: connecting to a cellular network via a wireless interface; connecting to one or more other UEs via the wireless interface to form a direct connection with the other UEs; receiving a first location reference signal through the direct connection with the other UEs, from which first timing information can be derived, the first timing information being related to the distance between the UE and the other UEs; determining a first location metric based on the first location reference signal, the first location metric being related to the position of the UE relative to the other UEs; receiving a second location reference signal through the cellular network, from which second timing information can be derived, the second timing information being related to the distance between the UE and a base station associated with the cellular network; determining a second location metric based on the second location reference signal, the second location metric being related to the position of the UE relative to the base station; and determining the location of the UE based at least in part on the first and second location metrics.

[0018] Furthermore, when determining the location of the UE, the processing circuitry can use multilateration-based technology or proximity detection technology to calculate the UE's location. Alternatively or additionally, when determining the location of the UE, the processing circuitry can: transmit first and second location measurements to a location server via the cellular network; and receive an indication of the UE's location from the location server.

[0019] In some implementations, the processing circuitry can decode payload data associated with a first positioning reference signal to obtain an indication of the location of one or more other UEs. Furthermore, in some implementations, the processing circuitry can receive multiple positioning reference signals from a corresponding number of other UEs, wherein timing information associated with the positioning reference signals is synchronized based on a synchronization process performed via a cellular network.

[0020] In some implementations, the first timing information can be synchronized with other UEs based on bidirectional timing estimation performed between the UE and other UEs. The first location metric may include one or more of the following: arrival time of a location reference signal; the difference in arrival time between location reference signals; the difference in arrival time between a location reference signal and a reference clock; received power of the location reference signal; received quality of the location reference signal; a timing estimation accuracy indicator; location information; or timing information sufficient for solving the location equation.

[0021] In some implementations, the processing circuitry also receives configuration information related to the configuration of the first positioning reference signal via a cellular network. Alternatively or further, in some implementations, the location of the UE can be determined locally by the UE through an application that receives at least the first and second location measurements from lower-level processing of the UE.

[0022] Consistent with another aspect described herein, the UE may include: a wireless interface; a computer-readable medium for storing processor-executable instructions; and processing circuitry for executing the processor-executable instructions. The processing circuitry may execute instructions to: connect to a second UE adjacent to the UE via a secondary link channel associated with the wireless interface; connect to a cellular network via the wireless interface; transmit a first location reference signal to the second UE on the secondary link channel, from which first timing information relating to the distance between the UE and the second UE can be derived; transmit a second location reference signal via the wireless interface, from which second timing information relating to the distance between the UE and a base station associated with the cellular network can be derived; and receive the location of the UE from a location server via the wireless interface, the location of the UE being determined at least in part based on the first and second location reference signals.

[0023] Consistent with another aspect described herein, a location server may include processing circuitry for: storing location indications of a plurality of anchor UEs deployed as part of a wireless network; receiving a first location metric from the anchor UEs, the first location metric including information relating to the location of a target UE relative to the anchor UE; receiving a second location metric relating to the location of the target UE relative to a base station in the wireless cellular network; and calculating the location of the target UE based on the first and second location metrics.

[0024] In some implementations, the first location metric may be based on communication of location reference signals exchanged on a secondary link channel formed between the target UE and the anchor UE. In some implementations, the anchor UEs may each be associated with a fixed location. In some implementations, the processing circuitry further performs the following operations: receiving a third location metric from multiple non-anchor UEs, wherein the calculation of the target UE's location is also based on the third location metric. In some implementations, the processing circuitry further performs the following operations: transmitting the calculated location of the target UE to the target UE.

[0025] Consistent with another aspect described herein, a method may include: connecting to a cellular network via a wireless interface; connecting to a second UE via the wireless interface to establish a direct connection with the second UE; receiving a first positioning reference signal via the direct connection with the second UE, from which first timing information related to the distance between the UE and the second UE can be derived; determining a first location metric based on the first positioning reference signal, the first location metric related to the location of the UE relative to the second UE; receiving a second positioning reference signal via the cellular network, from which second timing information related to the distance between the UE and a base station associated with the cellular network can be derived; determining a second location metric based on the second positioning reference signal, the second location metric related to the location of the UE relative to the base station; and determining the location of the UE based at least in part on the first and second location metrics.

[0026] Consistent with another aspect described herein, the UE may include: means for connecting to a cellular network via a wireless interface; means for connecting to a second UE via a wireless interface to form a direct connection with the second UE; means for receiving a first positioning reference signal via the direct connection with the second UE, from which first timing information can be derived, the first timing information being related to the distance between the UE and the second UE; means for determining a first location metric based on the first positioning reference signal, the first location metric being related to the position of the UE relative to the second UE; means for receiving a second positioning reference signal via the cellular network, from which second timing information can be derived, the second timing information being related to the distance between the UE and a base station associated with the cellular network; means for determining a second location metric based on the second positioning reference signal, the second location metric being related to the position of the UE relative to the base station; and means for determining the location of the UE based at least in part on the first and second location metrics.

[0027] Figure 1 This is an overview diagram illustrating an example of the implementation described in this article. (e.g.) Figure 1As shown, a base station (such as a base station associated with a wireless cellular network) can communicate with a mobile device (referred to as a User Equipment (UE)) tagged as UE_A. UE_A can also communicate directly with another UE tagged as UE_B to achieve D2D discovery or a communication channel. In 3GPP, a D2D discovery or communication channel may be referred to as a secondary link channel. A location server can perform location services for the wireless network and / or for the UE. The location server can, for example, obtain parameters that may include parameters related to different types of measured location metrics (such as signal timing data, signal received power data) and / or parameters related to calculated location (e.g., coordinate data obtained from a satellite-assisted location system or pre-configured during terminal installation, and distance measurements relative to a reference node), and determine the location (e.g., geographic location) of UE_A based on these parameters. In some implementations, the location server may alternatively or additionally determine the current speed and / or direction of travel for UE_A.

[0028] At least some of the location metrics can be obtained from the secondary link channel. For example, UE_A and UE_B can transmit and receive location signals (e.g., reference signals and / or reference signals accompanying data (payload)) on the secondary link channel, and the location metrics can be calculated based on these location signals. In some implementations, such as via a location server, the location metrics obtained on the secondary link channel can be combined with conventional location metrics (such as those obtained via one or more UE-eNB links) to obtain a more accurate determination of the location of the target UE (such as UE_A).

[0029] In one implementation, the location of UE_B can be determined in a relatively precise manner. For example, the location of UE_B may have been accurately determined using traditional positioning techniques (e.g., UE_B may be outdoors and have a good line-of-sight link with GPS satellites), or UE_B may be a fixed device installed by the wireless network operator. When installed in a fixed location, UE_B can be referred to as an "anchor" device. Furthermore, the "anchor" terminal can be a terminal that reliably knows its own coordinates. The presence of an anchor device near UE_A can assist in obtaining a more accurate location determination.

[0030] In some implementations, the location server can be omitted, and the location of UE_A can be determined by UE_A and / or another device. In this scenario, location can be performed by the UE, for example, by running a self-location application that takes into account information about signal location parameters from secondary links and / or cellular links.

[0031] Location metrics obtained from secondary link channels can improve UE location determination in various ways. For example, by using neighboring UEs to assist location determination, a greater number of sources can be used to obtain location metrics. That is, the deployment density of other UEs can be higher than the density of deployed base stations. Furthermore, as mentioned, in particularly challenging location scenarios, anchor UEs can be intentionally pre-installed inside buildings to increase location accuracy. Installing additional anchor UEs may be a more cost-effective solution compared to the cost of installing more base stations. Moreover, in future cellular systems, to more effectively support vehicle-to-vehicle applications, road infrastructure units (based on UE implementations) can be installed and can act as anchor nodes for locating terminals using D2D air interfaces.

[0032] Furthermore, because secondary link channels tend to be created based on proximity, the existence of a secondary link channel (e.g., a secondary link channel with a UE of known location) can be used to improve location determination for a target UE. That is, a UE with known coordinates can provide a coarse estimate of the target UE's location. The power used for the secondary link channel can also be a factor in determining the target UE's location (e.g., a low-power secondary link channel may indicate proximity to the target UE). The presence of other nearby UEs can also improve the accuracy of location.

[0033] Furthermore, the use of secondary link channels in location determination can be used to correct inaccuracies caused by hearability issues. Hearability problems tend to occur indoors, where the number of base stations a UE can detect may often be fewer than outdoors due to significant wall penetration losses. Using secondary link channels associated with other UEs (such as anchor UEs) can reduce indoor hearability problems. Besides location determination assistance, anchor UEs can perform other functions. For example, anchor UEs may include smart meters, advertising devices providing advertising in shopping malls, or other UEs whose primary function is not location determination assistance. In these scenarios, the accuracy of 3D positioning can be greatly improved, especially for vertical coordinates, which can often have low accuracy because base stations tend to be deployed at approximately the same height and relatively far apart, geometrically greatly diminishing the accuracy of vertical positioning.

[0034] Furthermore, the use of secondary link channels in location determination can improve the estimation accuracy of traditional location determination techniques. Due to the proximity nature of secondary link communication, the propagation conditions between UEs in the secondary link channel can be better than those from the base station to the UE. For example, the probability of a line-of-sight link can be higher due to the shorter distance, thus reducing distortion caused by non-line-of-sight links. Additionally, the signal-to-noise ratio on the secondary link channel can be better than that of the link from the UE to the base station.

[0035] Figure 2 This is a diagram of an example environment 200 in which the systems and / or methods described herein can be implemented. As shown, environment 200 may include UE 210, UE 212, and UE 214. Although Figure 2 The diagram shows 3 UEs, but in reality, environment 200 may include more or fewer UEs.

[0036] Environment 200 may also include wireless network 200. Wireless network 220 may include one or more networks that provide wireless network connectivity for UEs 210-214. For example, wireless network 220 may represent a wireless network providing cellular wireless coverage. In some implementations, wireless network 220 may be associated with a 3GPP / LTE-based network. Wireless network 220 may include a radio access network (RAN), including one or more base stations 225 and an evolved packet core (EPC). In an LTE-based network environment, base station 225 may be referred to as an enhanced node B (eNB). EPC may include a serving gateway (SGW) 230, a mobility management entity (MME) 235, and a packet data network gateway (PGW) 240. Home subscriber server (HSS) 250 and location server 260 associated with EPC, wireless network 220, or external networks are also included. Figure 2 It is shown in the middle.

[0037] UEs 210-214 may each include portable computing and communication devices, such as personal digital assistants (PDAs), smartphones, cellular phones, laptops capable of connecting to cellular wireless networks, tablets, etc. UEs 210-214 may also include non-portable computing devices, such as desktop computers, consumer or commercial devices, or other devices capable of connecting to wireless network 220. UEs 210-214 may connect to wireless network 220 via a wireless link.

[0038] UEs 210-214 may include a radio interface that allows them to connect to each other via a direct wireless connection. For example, each UE 210-214 may include a first radio transceiver for connecting to a cellular wireless network (such as a 3GPP / LTE-based network (i.e., radio network 220)) and a second radio transceiver for enabling WiFi-based communication (e.g., IEEE 802.11-based communication). UEs 210-214 can discover each other directly or with the assistance of radio network 220. UEs 210-214 can then connect directly to each other (e.g., via a direct WiFi path or via an Evolved Universal Terrestrial Radio Access (E-UTRAN) direct communication path without using radio network 220) to participate in secondary link communication.

[0039] eNB 225 may include one or more network devices that receive, process, and / or transmit traffic destined for and / or received from UE 210-214. eNB 225 may provide a wireless (i.e., radio) interface to UE 210-214.

[0040] SGW 230 may include one or more network devices that route data for traffic flows. SGW 230 may aggregate traffic received from one or more eNBs 225 and may transmit the aggregated traffic to external networks via PGW 240. SGW 230 may also function as a mobility anchor during inter-base station handover.

[0041] MME 235 may include one or more computing and communication devices that act as control nodes for the eNB, and / or include other devices that provide an air interface for wireless network 220. For example, MME 235 may perform operations on UEs 210-214 of wireless network 220 to: establish a session-associated bearer channel (such as a traffic flow) with UE 210-214, hand over UE 210-214 to another network, and / or perform other operations. MME 235 may perform regulatory operations on traffic intended for and / or received from UE 210-214.

[0042] PGW 240 may include one or more network devices that can aggregate traffic received from one or more SGW 230s and send the aggregated traffic to an external network. PGW 240 may also (or alternatively) receive traffic from an external network and send that traffic to UE 210-214 via SGW 230 and / or eNB 225.

[0043] HSS 250 may include one or more devices that can manage, update, and / or store subscriber profile information in memory associated with HSS 250. The profile information may identify the following: applications and / or services that the subscriber is licensed and / or can access; the mobile number book number (MDN) associated with the subscriber; bandwidth or data rate thresholds associated with the application and / or service; and / or other information. The subscriber may be associated with UE 210-214. Additionally or alternatively, HSS 250 may perform authentication, authorization, and / or billing operations associated with the subscriber and / or communication sessions with UE 210-214.

[0044] Location server 260 may represent functions implemented by one or more network devices to perform location determination functions for UE 210-214. For example, location server 260 may receive and store location determination-related parameters from UE 210-214, eNB 225, or other devices. Some network devices may be located in fixed, known locations. For example, eNB 225 and anchor UE 210-214 may be installed in fixed locations. Location server 260 may store the locations of these devices. Location server 260 may periodically or occasionally calculate the location of UE 210-214 and maintain up-to-date data structures indicating the current location of UE 210-214. Based on these parameters and the known locations of various devices, location server 260 may use location calculation techniques such as multi-point positioning or proximity detection to determine the current location of a target UE (such as one of UE 210-214).

[0045] exist Figure 2 The number of devices and / or networks shown is provided for illustrative purposes only. In reality, besides... Figure 2 In addition to those shown, there may be more devices and / or networks; fewer devices and / or networks; different devices and / or networks; or devices and / or networks arranged differently. Alternatively or additionally, one or more of the devices in environment 200 may perform one or more functions, which are described as being performed by one or more other devices in environment 200.

[0046] As mentioned earlier, in some cases, the UE that communicates directly with the target UE (i.e., the UE whose location will be determined) can be associated with a known location. These UEs can be referred to as "anchor" UEs. Anchor UEs can include UEs installed by the network provider at fixed locations to serve as anchor terminals. In some implementations, anchor UEs can also include mobile UEs (such as a UE used by a user) whose location is precisely known (e.g., the UE may be outdoors and in an area that can be precisely located using satellite positioning technology).

[0047] Figure 3 This is a conceptual diagram illustrating the use of an anchor UE to determine the location of a target UE. Figure 3 In this example, it is assumed that the location of UE 310 (“Target UE”) is desired. Anchor UEs 320 and 330 may be near Target UE 310. Target UE 310 may be attached to serving eNB 340. Furthermore, two other eNBs, shown as adjacent eNBs 350 and 360, may be close enough to Target UE 310 that it can receive a location reference signal from the adjacent eNBs 350 and 360.

[0048] eNBs 340-360 may include internal reference clocks that are synchronized relative to each other. Additionally, eNBs 340-360 may broadcast synchronization signals to synchronize the reference clocks of UEs 310-330. Synchronization of the reference clocks of eNBs 340-360 and UEs 310-360 allows positioning reference signals to be transmitted and timing information to be extracted by the receiving UE (such as target UE 310). In some implementations, the reference clocks of UEs 310-330 may be synchronized based on one of the UEs 310-330 transmitting a synchronization or reference signal, rather than through a synchronization signal from the eNB. In some implementations, anchor UEs 320-330 may be configured to remain in sleep or low-power mode most of the time, but are configured (such as by eNB 340-360) to wake up at predetermined intervals to process synchronization signals and / or transmit positioning reference signals for D2D assisted positioning purposes.

[0049] exist Figure 3In this implementation, target UE 310 can receive location reference signals from eNBs 340-360 and anchor UEs 320 and 330. The location reference signals from anchor UEs 320 and 330 may include signals transmitted on a direct secondary link channel. The location reference signals from eNBs 340-360 may include signals transmitted on a cellular link associated with wireless network 220. In one implementation, the location reference signals received by target UE 310 may include timing information that may be related to the distance between target UE 310 and the transmission source. For example, differences in timing information and / or signal arrival times from various sources (such as eNBs 340-360 and anchor UEs 320 and 330) may correspond to the distance of target UE 310 from the transmission source. Because the location (e.g., three-dimensional coordinates) of each transmission source may be known, multi-point positioning techniques can be applied to the calculated distance to determine the location of target UE 310.

[0050] In some implementations, the target UE 310 can autonomously detect anchor UEs that are close to it. Alternatively or additionally, the target UE 310 may receive information from the serving eNB 340 indicating a range of potential nearby anchor UEs. The information from the serving eNB 310 may include configuration information related to the positioning reference signal.

[0051] exist Figure 3 In the diagram, multi-point positioning is graphically represented by arcs 372-380, each of which indicates a specific distance from the transmission source. The intersection of these arcs corresponds to the location of the target UE 310. As shown, arc 372 corresponds to a specific distance from the serving eNB 340; arc 374 corresponds to a specific distance from the adjacent eNB 360; arc 376 corresponds to a specific distance from the adjacent eNB 350; arc 378 corresponds to a specific distance from the anchor UE 320; and arc 380 corresponds to a specific distance from the anchor UE 330.

[0052] In some implementations, the calculation of the location of the target UE 310 can be performed by the target UE 310 itself. Alternatively or additionally, the calculation of the location of the target UE 310 can be performed by the location server 260, or with the assistance of the location server 260. For example, UEs 310-330 and eNBs 340-360 can transmit location metrics to the location server 260 via the wireless network 220, which are derived from the location reference signal and potentially other information, such as measured values ​​related to the signal strength of the location reference signal. Compared to implementations that obtain location metrics solely based on communication with eNBs 340-360, the location of the target UE 310 can potentially be determined more accurately by using a secondary link channel to obtain more location metrics.

[0053] Figure 4 This is a conceptual diagram illustrating the location determination of a target UE using a non-anchored UE (also referred to as an auxiliary UE in this document). Figure 4 In, with Figure 3 Similarly, assuming the desired location of target UE 310 is obtained. Target UE 310 can form secondary link channels with nearby auxiliary UEs 420, 425, and 430. Auxiliary UEs 420-430 can be unanchored mobile UEs. The locations of auxiliary UEs 420-430 can be unknown or can be not precisely known. Target UE 310 can be attached to serving eNB 340 and can receive location reference signals from neighboring UEs 350 and 360.

[0054] exist Figure 4 In this scenario, the coordinates of the auxiliary UEs 420-430 are not known in advance by the auxiliary UEs 420-430 and / or the location server 260. Instead, the relative positions of the auxiliary UEs 420-430 and the target UE 310 can be jointly estimated (i.e., UE-UE position measurement) by collecting position metrics obtained from the secondary link channel. In some implementations, the relative positions of the auxiliary UEs 420-430 can be combined with an absolute position estimate (based on a position estimate determined by a positioning reference signal transmitted by the eNB). For example, a first position metric (based on the exchange of positioning reference signals between UEs) and a second position metric (based on positioning reference signals transmitted from the eNB to the UE) can be forwarded to the location server 260. The location server 260 can combine the first and second position metrics to calculate a relatively precise absolute location relative to the target UE 310.

[0055] Figure 5 This diagram conceptually illustrates the location determination of a target UE using a combination of an anchor UE and an auxiliary UE. Figure 5 In, with Figure 3 and Figure 4 Similarly, assuming the desired location is target UE 310, target UE 310 can form secondary link channels with nearby anchor UEs 320-330 and auxiliary UEs 420-430. Figure 5 In this case, location determination can be based on location measurements received from both the anchor UE and the auxiliary UE, as well as location measurements obtained relative to the serving eNB 340 and / or neighboring eNBs 350-360. For example, the location server 260 can use a multi-point positioning technique to obtain a relatively accurate three-dimensional location of the target UE 310, based on location measurements received from the anchor UEs 320-330, auxiliary UEs 420-430, and eNBs 340-460, as well as the stored location coordinates of the anchor UEs 320-330 and eNBs 340-360.

[0056] Figure 6 This is a flowchart illustrating an example of process 600, which can be used to determine the location of the target UE when a secondary link channel is available between the target UE and one or more other UEs. In the context of process 600, the other UEs can include anchored UEs and non-anchored UEs. Furthermore, although process 600 will be described primarily based on observed time difference of arrival (TDOA) positioning techniques, other positioning techniques such as those based on time of arrival (TOA) can alternatively be employed.

[0057] Processing 600 may include receiving a location reference signal (block 610) by the target UE. As mentioned above, the location reference signal may be a signal received from other UEs (such as an anchored UE or a non-anchored UE, and / or from an eNB). In some implementations, the location reference signal may include a signal transmitted using spectrum resources defined by the radio network. For example, control signaling may be transmitted or broadcast to UEs 210-214 to configure the UE to use specific spectrum resources for the location reference signal, and / or to use specific timing parameters (such as parameters with specific uplink timing values, downlink timing values, timing advance values, and / or other values), configuration parameters, or other parameters. In some implementations, the location reference signal may have configurable bandwidth. Furthermore, the location reference signal may include, or be associated with, payload data carrying location-related information, such as the location (e.g., coordinates) of the UE or eNB making the transmission.

[0058] In one implementation, the positioning reference signal may be based on the positioning reference signal described in 3GPP standard releases 8-10. Alternatively or additionally, the positioning reference signal may include or be based on a Channel State Information Reference Signal (CAI-RS) or a Cell-Specific Reference Signal (C-RS). As previously mentioned, the wireless network 220 may transmit a synchronization signal to synchronize the UE's internal clock. The target UE 310 can use the received positioning reference signal (and its synchronized clock) to determine the signal arrival time difference, which is referred to as the Reference Signal Time Difference (RSTD) between positioning reference signals from different transmission devices (such as the eNB and the UE).

[0059] Processing 600 may also include decoding the received positioning reference signal (block 620). As described, in some implementations, the transmitted positioning reference signal may include payload data, such as coordinates, that define the location of the UE transmitting the positioning reference signal. Decoding the received positioning reference signal may include extracting any payload data (such as the location of the anchor UE) from the positioning reference signal.

[0060] Processing 600 may further include determining a location metric (block 630) based on the received positioning reference signal. This location metric may include or be derived from timing values, such as values ​​estimating the arrival time of the positioning reference signal and / or values ​​representing the difference in arrival times. The value representing the difference in arrival times may be estimated relative to the arrival time of the positioning reference signal from the serving eNB 340 or other configured reference cell. In some implementations, the received signal power of the positioning reference signal may also be used as a factor in estimating the arrival time and / or the difference in arrival times.

[0061] Timing values ​​related to the transmission of auxiliary / anchor UEs can be estimated as one or more of the following:

[0062] • Uplink (UL) timing T UL T UL It can be equal to T DL +RTT, where T DL This indicates the receive downlink (DL) timing of the serving eNB 340, and RTT indicates the round-trip time to the serving eNB 340.

[0063] Downlink (DL) timing T DL This timing is related to the arrival of the downlink positioning reference signal from the serving eNB 340 at the UE antenna connector.

[0064] • TA / 2 (Timing Advance) timing. TA / 2 can represent the timing corresponding to the eNB transmission timing when RTT and DL are measured without errors. TA / 2 can also be defined relative to the serving eNB 340.

[0065] • Other timing measurements or techniques.

[0066] Processing 600 may also include reporting location metrics to the location server (block 640). In one implementation, location metrics may be reported using messages exchanged in accordance with a positioning protocol. The reported location metrics may include, for each UE (such as an auxiliary or anchor UE) and for each neighboring eNB, the RSTD and the location reference signal received power. This message may be relayed to the location server 260 via the serving eNB 340.

[0067] Processing 600 may further include determining the location of the target UE based on the received location metrics and locations of the eNB and the anchor UE (block 650). As previously mentioned, performing this location determination may be based on location metrics generated from location reference signals received from both the anchor UE and the auxiliary UE, and on location metrics generated from location reference signals received from the serving eNB 340 and / or neighboring eNBs 350-360. For example, location server 260 may use a multi-point positioning technique to obtain a relatively accurate three-dimensional location of the target UE 310, based on location metrics received from the anchor UEs 320-330, auxiliary UEs 420-430, and eNBs 340-460, and the stored location coordinates of the anchor UEs 320-330 and eNBs 340-360.

[0068] The above Figure 6 In the description, timing values ​​are generally described based on downlink transmissions of the positioning reference signal to the target UE. However, in some implementations, uplink transmissions can be used to generate timing values. Generating timing values ​​using uplink transmissions can be referred to herein as Uplink Time Difference of Arrival (U-TDOA). In U-TDOA, the wireless network 220 (such as eNB 340-360) can estimate the time difference of arrival of the positioning reference signal transmitted by the target UE 310.

[0069] Figure 7This is a flowchart illustrating an example of process 700, which can be used to determine the location of target UE 310 based on uplink transmissions from target UE 310. First, process 700 may include the transmission of a location reference signal by the target UE (block 710). The transmission of the location reference signal may be scheduled by the serving eNB 340 and / or transmitted using predefined channel or spectrum resources. In one implementation, the uplink transmission may be based on a 3GPP-standardized sounding reference signal (SRS) or demodulation reference signal (DMRS). The uplink transmission may include payload data and / or may be configured to include a wideband symbol sequence with good autocorrelation and cross-correlation properties. The transmission of the location reference signal may be via secondary links to nearby anchor UEs and auxiliary UEs, and also via a cellular or general radio interface to the wireless network 220.

[0070] Processing 700 may further include estimating a TDOA or TOA value by the serving eNB and / or neighboring eNB based on uplink positioning reference signals from the target UE (block 720). This TDOA / TOA value may represent a location metric similar to that calculated by the target UE 310 and for... Figure 6 Those described.

[0071] Processing 700 may also include estimating the TDOA / TOA value by other UEs (e.g., anchor UE and auxiliary UE near the target UE) based on an uplink positioning reference signal from the target UE and propagating on the secondary link channel (block 730). The TDOA / TOA value, along with other information such as the signal strength of the positioning reference signal, can represent a location metric that can be transmitted to the location server 260.

[0072] Processing 700 may also include determining the location of the target UE by the location server 260 (block 740). The location may be based on location metrics (i.e., TDOA / TOA values) received from anchor UEs 320-330, auxiliary UEs 420-430, serving eNB 340, and / or neighboring eNBs 350-360.

[0073] The following section discusses eight examples involving the use of secondary link channels, which provide location metrics that can be used to determine the location of the UE.

[0074] Example 1: TDOA (Device-to-Device Observational Analysis) for Anchored Device-to-Device Assistance

[0075] Network operators or mobile subscribers can install fixed anchor UEs in various locations. For example, network operators can install a number of relatively low-cost stationary anchor UEs in indoor retail stores, sports venues, etc. Configuration information related to the location reference signal generated by the anchor UE can be provided to the UE via Radio Resource Control (RRC) layer signaling transmitted through the wireless network 220. Alternatively, this information can be pre-configured through the application layer. The target UE 310 can then measure the RSTD on the secondary link channel connected to the anchor UE and report the RSTD value to the location server 260 via the wireless network 220.

[0076] Example 2: TDOA for non-anchored device-to-device assistance observation

[0077] This scenario corresponds to the general-purpose scenario in Example 1. The difference is that the locations of the auxiliary UEs 420-430 may not be known prior to the location server 260 or the location application of the target UE. In this scenario, the locations of the auxiliary UEs 420-430 and the target UE 310 can be jointly calculated based on location metrics obtained on the secondary link channel and measurements of signal location parameters on the cellular link. The location server 260 can collect UE-UE location metrics from the UE cluster and employ joint location determination techniques to potentially provide more accurate location determination than locating each UE independently.

[0078] Example 3: U-TDOA-anchored device-to-device assistance

[0079] In this scenario, location server 260 can improve the uplink-based positioning method using location metrics obtained from the UE-UE secondary link channel. The UE-UE location metrics can be obtained from both ends of the secondary link channel (i.e., at the target UE 310 and the anchor UEs 320-330).

[0080] Example 4: U-TDOA non-anchored device-to-device assistance

[0081] This situation is similar to Example 2, except that in this example, the uplink arrival time difference method can be used by the network to perform location detection between the target UE 310 and the auxiliary UEs 420-430.

[0082] Example 5: Anchoring and positioning based on synchronous UE

[0083] This scheme assumes that the target UE 310 can calculate its location itself (e.g., based on satellite-assisted location determination). Due to the deployed synchronization (e.g., provided by the wireless network 220), only one-way positioning reference signal transmission is sufficient to estimate TOA / TDOA. To determine its location, the target UE 310 can learn the location of the anchor UEs 320-330, such as through higher-level communication from the wireless network 220, or by directly receiving it in the payload data associated with the positioning reference signal.

[0084] Example 6: Anchoring and positioning based on asynchronous UEs

[0085] This scenario is similar to Example 5, except that the UEs can be asynchronous and require bidirectional timing estimation to synchronize them. In this context, the target UE 310 can transmit messages to the anchor UE on the secondary link channel and receive synchronization response messages from the anchor UE on the secondary link channel. This message exchange can be used to measure round-trip time and / or establish shared timing.

[0086] Example 7: Non-anchored positioning based on synchronous UE

[0087] This example is a generalized scenario of Example 5, in which one or more UEs are not anchored (auxiliary UEs). In this scenario, the UE location maps of both anchored and non-anchored UEs can be reconstructed based on location metrics exchanged using secondary link channels, which can then be used to locate the non-anchored UEs.

[0088] Example 8: Non-anchored positioning based on asynchronous UEs

[0089] This situation corresponds to a general-purpose scenario where each timing / distance estimate is performed in a bidirectional positioning manner, and only a subset of UEs or eNBs have known locations.

[0090] Figure 8 This is a diagram of the components of an example device 800. Figure 1-5 Each of the devices shown may include one or more devices 800. Device 800 may include a bus 810, a processor 820, a memory 830, an input component 840, an output component 850, and a communication interface 860. In another implementation, device 800 may include more, fewer, different, or differently arranged components.

[0091] Bus 810 includes one or more communication paths that allow communication between components of device 800. Processor 820 may include a processor, microprocessor, or processing logic capable of interpreting and executing instructions. Memory 830 may include any type of dynamic storage device that can store information and instructions for execution by processor 820, and / or include any type of non-volatile storage device that can store information used by processor 820.

[0092] Input component 840 may include mechanisms that allow an operator to input information into device 800, such as a keyboard, keypad, buttons, switches, etc. Output component 850 may include mechanisms that output information to the operator, such as a display, speaker, one or more light-emitting diodes (LEDs), etc.

[0093] The communication interface 860 may include any transceiver-like mechanism that enables the device 800 to communicate with other devices and / or systems. For example, the communication interface 860 may include an Ethernet interface, an optical interface, a coaxial interface, etc. The communication interface 860 may include wireless communication devices, such as infrared (IR) receivers, cellular wireless devices, Bluetooth wireless devices, etc. The wireless communication device may be coupled to external devices, such as remote controls, wireless keyboards, mobile phones, etc. In some embodiments, the device 800 may include more than one communication interface 860. For example, the device 800 may include both an optical interface and an Ethernet interface.

[0094] Device 800 can perform some of the operations described above. Device 800 can perform these operations in response to processor 820 executing software instructions stored in a computer-readable medium such as memory 830. A computer-readable medium can be defined as a non-transitory memory device. A memory device can be contained in a single physical storage device or span a space across multiple physical storage devices. Software instructions can be read into memory 830 from another computer-readable medium or from another device. Software instructions stored in memory 830 can cause processor 820 to perform the processes described herein. Alternatively, hard-wired circuitry can be used in place of or in combination with software instructions to implement the processes described herein. Therefore, the implementations described herein are not limited to any specific combination of hardware circuitry and software.

[0095] In the foregoing description, various preferred embodiments have been described with reference to the accompanying drawings. However, it will be apparent that various modifications and changes can be made, and further embodiments can be implemented without departing from the broader scope of the invention as set forth in the following claims. The description and drawings should therefore be considered exemplary rather than restrictive.

[0096] For example, although for Figure 6 and Figure 7 A series of blocks have been described, but the order of the blocks can be modified in other implementations. Furthermore, blocks without dependencies can be executed in parallel.

[0097] It is evident that the aspects of the examples described above can be implemented in many different forms of software, firmware, and hardware as illustrated in the figures. The actual software code or specialized control hardware used to implement these aspects should not be construed as limiting. Therefore, the operation and behavior of these aspects are not described with reference to specific software code—it should be understood that the software and control hardware can be designed to implement these aspects based on the aspects described herein.

[0098] Furthermore, certain portions of this invention can be implemented as "logic" that performs one or more functions. This logic may include hardware such as application-specific integrated circuits (ASICs) or field-programmable gate arrays (FPGAs), or a combination of hardware and software.

[0099] Although specific combinations of features are described in the claims and / or disclosed in the description, these combinations are not intended to limit the invention. In fact, many of these features can be combined in ways that are not specifically described in the claims and / or disclosed in the description.

[0100] Elements, actions, or instructions used in this application should not be construed as critical or necessary to the invention unless explicitly stated otherwise. Furthermore, the word "based on" is intended to mean "at least partially based on," unless otherwise explicitly stated.

Claims

1. A user equipment (UE) including a memory and processing circuitry, the processing circuitry being configured to cause the UE to: when executing instructions stored in the memory. It connects to the cellular network via a wireless interface; Receive information indicating a second UE located near the UE and configuration information for a positioning reference signal transmitted by the second UE, wherein the positioning reference signal is transmitted at predetermined intervals; The wireless interface is used to connect to the second UE to form a direct connection with the second UE; Based on the configuration information, a first positioning reference signal is received via the direct connection with the second UE. From the first positioning reference signal, first timing information related to the distance between the UE and the second UE can be derived, wherein the first timing information is synchronized with the second UE based on the bidirectional timing estimation performed between the UE and the second UE. A first position metric is determined based on the first positioning reference signal. The first position metric is related to the position of the UE relative to the second UE. The first position metric includes the positioning reference signal received power. The UE receives a second positioning reference signal via the cellular network, from which second timing information related to the distance between the UE and a base station associated with the cellular network can be derived. A second location metric is determined based on the second positioning reference signal, and the second location metric is related to the position of the UE relative to the base station; Determine a coarse location estimate for the UE, the coarse location estimate being at least in part based on the known location of the target UE having a low-power secondary link channel with the UE; and The location of the UE is determined at least based on the rough location estimate and the first and second location metrics.

2. The UE according to claim 1, wherein, When the location of the UE is determined, the processing circuit is further configured to: The location of the UE is calculated using multi-point positioning technology or proximity detection technology.

3. The UE according to claim 1, wherein, When the location of the UE is determined, the processing circuit is further configured to: The first location metric and the second location metric are transmitted to the location server (260) via the cellular network; and Receive the location indication of the UE from the location server.

4. The UE according to claim 1, wherein, The processing circuit is also used for: Decode the payload data associated with the first positioning reference signal to obtain an indication of the location of the second UE.

5. The UE according to claim 1, wherein, The processing circuit is also used for: Multiple positioning reference signals are received from one or more other UEs, wherein timing information associated with the multiple positioning reference signals is synchronized based on a synchronization process performed via the cellular network.

6. The UE according to claim 1, wherein, The first location metric includes one or more of the following: Location reference signal arrival time; Time difference of arrival between positioning reference signals; The time difference between the positioning reference signal and the reference clock; Positioning reference signal reception quality; A timed estimation accuracy indicator; Location information; or Sufficient timing information to solve the location equation.

7. The UE according to claim 1, wherein, The location of the UE is determined locally by the UE through an application that receives at least the first location metric and the second location metric from a lower-level processing of the UE.

8. The UE according to claim 1, wherein, After connecting the second UE, the processing circuit is also used for: Synchronization messages are transmitted via the direct connection with the second UE; Receive synchronization response message from the second UE; and The first timing information is synchronized based on the timing response message.

9. A method implemented by a user equipment (UE) (310), the method comprising: Connect to a cellular network via a wireless interface; Receive information indicating a second UE located near the UE and configuration information for a positioning reference signal transmitted by the second UE, wherein the positioning reference signal is transmitted at predetermined intervals; The wireless interface is used to connect to the second UE to form a direct connection with the second UE; Based on the configuration information, a first positioning reference signal is received via the direct connection with the second UE. From the first positioning reference signal, first timing information related to the distance between the UE and the second UE can be derived, wherein the first timing information is synchronized with the second UE based on the bidirectional timing estimation performed between the UE and the second UE. A first position metric is determined based on the first positioning reference signal. The first position metric is related to the position of the UE relative to the second UE. The first position metric includes the positioning reference signal received power. The UE receives a second positioning reference signal via the cellular network, from which second timing information related to the distance between the UE and a base station associated with the cellular network can be derived. A second location metric is determined based on the second positioning reference signal, and the second location metric is related to the position of the UE relative to the base station; Determine a coarse location estimate for the UE, the coarse location estimate being at least in part based on the known location of the target UE having a low-power secondary link channel with the UE; and The location of the UE is determined at least based on the coarse location estimate, the first location metric, and the second location metric.

10. The method according to claim 9, wherein, Determining the location of the UE also includes: The location of the UE is calculated using a multi-point positioning technique or a proximity-based technique.

11. The method of claim 9, further comprising: Decode the payload data associated with the first positioning reference signal to obtain an indication of the location of the second UE.

12. The method according to claim 9, further comprising: Multiple location reference signals are received from multiple corresponding additional UEs, wherein timing information associated with the multiple location reference signals is synchronized based on a synchronization process performed via the cellular network.

13. The method according to claim 9, wherein, The first location metric includes one or more of the following: The arrival time of the positioning reference signal; Time difference of arrival between positioning reference signals; The time difference between the location reference signal and the reference clock; or Positioning reference signal reception quality.

14. The method of claim 9, further comprising, after connecting the second UE, Synchronization messages are transmitted via the direct connection with the second UE; Receive synchronization response message from the second UE; and The first timing information is synchronized based on the timing response message.

15. A user equipment (UE), comprising: Devices for connecting to cellular networks via a wireless interface; A means for receiving information indicating a second UE located near the UE and configuration information for a positioning reference signal transmitted by the second UE, wherein the positioning reference signal is transmitted at predetermined intervals; A means for connecting to a second UE via the wireless interface to form a direct connection with the second UE; A means for receiving a first positioning reference signal via the direct connection with the second UE and based on the configuration information, wherein the first positioning reference signal is used to derive first timing information related to the distance between the UE and the second UE, wherein the first timing information is synchronized with the second UE based on a bidirectional timing estimation performed between the UE and the second UE; A means for determining a first position metric based on the first positioning reference signal, the first position metric being related to the position of the UE relative to the second UE, wherein the first position metric includes positioning reference signal received power; A means for receiving a second positioning reference signal via the cellular network, from which second timing information related to the distance between the UE and a base station associated with the cellular network can be derived; A means for determining a second location metric based on the second positioning reference signal, the second location metric being related to the position of the UE relative to the base station; A means for determining a coarse location estimate for the UE, the coarse location estimate being at least in part based on the known location of the target UE having a low-power secondary link channel with the UE; and A means for determining the location of the UE based at least on the coarse location estimate, the first location metric, and the second location metric.

16. The UE according to claim 15, wherein, Determining the location of the UE also includes: The location of the UE is calculated using a multi-point positioning technique or a proximity-based technique.

17. The UE according to claim 15, further comprising: A means for decoding payload data to obtain an indication of the location of the second UE, the payload data being associated with the first positioning reference signal.

18. The UE according to claim 15, further comprising: A means for receiving multiple positioning reference signals from a plurality of corresponding additional UEs, wherein timing information associated with the plurality of positioning reference signals is synchronized based on a synchronization process performed via the cellular network.

19. The UE according to claim 15, further comprising: A means for transmitting synchronization messages via the direct connection with the second UE after the second UE has been connected; A means for receiving a synchronization response message from the second UE; as well as A device for synchronizing the first timing information based on the synchronization response message.

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