System and method for facilitating position determination by beamforming of positioning reference signals

Abstract

The present application relates to systems and methods for facilitating position determination by beamforming of positioning reference signals. The present invention provides techniques for locating a mobile device in a wireless network using directional positioning reference signals (PRS), also referred to as PRS beamforming. In an example method, a plurality of directional PRSs (SI, S2) are generated for at least one cell of a base station (410), such that each of the plurality of directional PRSs includes at least one signal characteristic and a transmission direction, either or both of which may be different or unique. The plurality of directional PRSs are transmitted within the at least one cell, such that each of the plurality of directional PRSs is transmitted in the transmission direction. A mobile device (420) may acquire and measure at least one of the directional PRSs identifiable using associated signal characteristics. The measurements may be used to assist positioning methods such as OTDOA and ECID and reduce multipath.

Description

[0001] This application is a divisional application of the invention patent application with application date of June 27, 2018 and application number 201880047905.0, entitled “System and method for facilitating position determination by beamforming of positioning reference signals”. Background Art

[0002] Obtaining the location or position of a mobile device that is accessing a wireless network may be useful for many applications, including, for example, emergency calls, personal navigation, asset tracking, locating friends or family members, etc. Existing positioning methods include methods based on measuring radio signals transmitted from a variety of devices, including satellite vehicles (SVs) and terrestrial radio sources in wireless networks, such as base stations and access points. In methods based on terrestrial radio sources, a mobile device may measure the timing of signals received from two or more base stations and determine the time of arrival, the time difference of arrival and / or the time of reception - the time difference of transmission. Combining such measurements with the known locations of the base stations and the known transmission times from each base station may enable positioning of the mobile device using such positioning methods as Observed Time Difference of Arrival (OTDOA) or Enhanced Cell ID (ECID).

[0003] To further aid in position determination (e.g., for OTDOA), positioning reference signals (PRS) may be transmitted by base stations in order to increase both the measurement accuracy and the number of different base stations whose timing measurements may be obtained by mobile devices. However, position accuracy may be impaired by several factors, including errors, inaccuracies in position measurements, and multipath effects, where PRS signals may be reflected, refracted, or scattered by intervening obstacles such as trees, walls, buildings, and traffic. Methods and techniques to reduce or overcome such factors may therefore be beneficial. Summary of the invention

[0004] An example of a method for supporting positioning of a mobile device at a first base station according to the present invention includes: generating a plurality of directional positioning reference signals (PRS) for at least one cell of the base station, such that each of the plurality of directional PRSs includes at least one signal characteristic and a transmission direction; and transmitting each of the plurality of directional PRSs within the at least one cell, such that each of the plurality of directional PRSs is transmitted in the transmission direction.

[0005] Implementation of this method may include one or more of the following features. The at least one signal characteristic may include frequency, frequency offset, code sequence, muting pattern, transmission time, or any combination thereof. Transmitting the multiple directional PRSs within the at least one cell may include directing the multiple directional PRSs via a controllable antenna array configured to beamform each directional PRS in the transmission direction. The transmission direction may include a continuous horizontal angle range, a continuous vertical angle range, or a combination thereof. At least one of the multiple directional PRSs may be detected by the mobile device to facilitate the determination of the position of the mobile device based on an observed time difference of arrival (OTDOA) positioning method, an angle of departure (AOD) positioning method, or an enhanced cell ID (ECID) positioning method, or any combination thereof, at a device with positioning capabilities. At least one of the multiple directional PRSs may be detected by the mobile device based on the transmission direction of the at least one of the multiple directional PRSs, at least one signal characteristic of the at least one of the multiple directional PRSs, or a combination thereof. The method may further include sending the transmit direction of at least one of the plurality of directional PRSs or at least one of the at least one signal characteristic of the at least one of the plurality of directional PRSs to the mobile device. The sending may be based on a broadcast within the at least one cell. The position determination at the positioning-capable device may include determining the presence or absence of a multipath of at least one of the plurality of directional PRSs based on the transmit direction of at least one of the plurality of directional PRSs and an estimated position of the mobile device, such that determining the position of the mobile device at the positioning-capable device is based at least in part on the determined presence or absence of a multipath. The estimated position of the mobile device may be based at least in part on a serving cell of the mobile device. The positioning-capable device may include a second base station different from the first base station, the mobile device, or a location management function (LMF), and such that the method further includes sending the transmit direction of at least one of the plurality of directional PRSs to the positioning-capable device. The at least one cell may be a serving cell of the mobile device. At least one of the at least one signal characteristic and the transmit direction of each of the plurality of directional PRSs may be unique.

[0006] An example of a method at a mobile device for supporting positioning of the mobile device according to the present invention includes: receiving, at the mobile device, a first directional positioning reference signal (PRS) transmitted by a first base station within at least one cell of the first base station, such that the first directional PRS includes at least one first signal characteristic and a first transmission direction; obtaining at least one first measurement result of the first directional PRS based at least in part on the at least one first signal characteristic; and facilitating, at a device with positioning capabilities, determination of a position of the mobile device based at least in part on the at least one first measurement result.

[0007] Implementation of this method may include one or more of the following features. The at least one first signal characteristic may include carrier frequency, frequency offset, code sequence, muting pattern, bandwidth, transmission time, or any combination thereof. The first directional PRS may be transmitted from the first base station via a controllable antenna array configured to beamform the first directional PRS in the first transmission direction. The first transmission direction may include a continuous horizontal angle range, a continuous vertical angle range, or a combination thereof. The method may further include receiving the at least one first signal characteristic of the first directional PRS from the first base station or from a location management function (LMF). The at least one first measurement result of the first directional PRS may include time of arrival (TOA), reference signal time difference (RSTD), received signal strength indication (RSSI), reference signal received power (RSRP), reference signal received quality (RSRQ), angle of arrival (AOA), signal propagation time, detection of at least one signal characteristic, or any combination thereof. The position determination of the mobile device at the device with positioning capability may be based on an observed time difference of arrival (OTDOA) positioning method, an angle of departure (AOD) positioning method, or an enhanced cell ID (ECID) positioning method, or any combination thereof. The location determination of the mobile device at the positioning-capable device may include determining the presence or absence of a multipath of the first directional PRS based on the first transmit direction and the estimated location of the mobile device, such that the determination of the location of the mobile device at the positioning-capable device is based at least in part on the determined presence or absence of multipath. The estimated location of the mobile device may be based at least in part on a serving cell of the mobile device. The positioning-capable device may include the first base station or a location management function (LMF), and such that the method further includes sending at least one first measurement result of the first directional PRS to the positioning-capable device. The method may include: receiving, at the mobile device, a second directional PRS transmitted by a second base station within at least one cell of the second base station, such that the second directional PRS includes at least one second signal characteristic and a second transmission direction, and such that the at least one second signal characteristic of the second directional PRS and the second transmission direction are different from the at least one first signal characteristic and the first transmission direction of the first directional PRS, respectively; obtaining at least one second measurement result of the second directional PRS based at least in part on the at least one second signal characteristic of the second directional PRS; and facilitating location determination of the mobile device at or at a device with positioning capabilities based at least in part on the at least one first measurement result and the at least one second measurement result. The at least one cell of the first base station may be a serving cell of the mobile device. At least one of the at least one signal characteristic of the first directional PRS and the first transmission direction may be unique.

[0008] An example of a method for supporting positioning of a mobile device at a device with positioning capabilities according to the present invention includes: obtaining from the mobile device at least one first measurement result of a first directional positioning reference signal (PRS) transmitted by a first base station in at least one cell of the first base station, such that the first directional PRS includes at least one first signal characteristic and a first transmission direction; and determining the position of the mobile device based at least in part on the at least one first measurement result and the first transmission direction.

[0009] Implementations of this method may include one or more of the following features. The at least one first signal characteristic may include a carrier frequency, a frequency offset, a code sequence, a muting pattern, a bandwidth, a transmission time, or any combination thereof. The first directional PRS may be transmitted from the first base station via a controllable antenna array configured to beamform the first directional PRS in the first transmission direction. The first transmission direction may include a continuous horizontal angle range, a continuous vertical angle range, or a combination thereof. The positioning-capable device may include the mobile device, and such that the method further includes receiving the at least one first signal characteristic and the first transmission direction from the first base station or from a location management function (LMF). The first transmission direction may be received from the first base station by receiving a broadcast signal from the first base station. The positioning-capable device may include the first base station or a location management function (LMF), and such that the method further includes receiving the at least one first measurement result from the mobile device. The method may also include sending the at least one first signal characteristic to the mobile device. The at least one first measurement result of the first directional PRS may include a time of arrival (TOA), a reference signal time difference (RSTD), a received signal strength indication (RSSI), a reference signal received power (RSRP), a reference signal received quality (RSRQ), an angle of arrival (AOA), a signal propagation time, a detection of at least one first signal characteristic, or any combination thereof. Determining the position of the mobile device may be based on an observed time difference of arrival (OTDOA) positioning method, an angle of departure (AOD) positioning method, or an enhanced cell ID (ECID) positioning method, or any combination thereof. The method may include determining the presence or absence of a multipath of the first directional PRS based on the first transmission direction and the estimated position of the mobile device, such that determining the position of the mobile device is based at least in part on the determined presence or absence of a multipath. The estimated position of the mobile device may be based at least in part on a serving cell of the mobile device. The method may include: obtaining from the mobile device at least one second measurement result of a second directional PRS transmitted by a second base station in at least one cell of the second base station, such that the second directional PRS includes at least one second signal characteristic and a second transmission direction, and such that the at least one second signal characteristic and the second transmission direction of the second directional PRS are different from the at least one first signal characteristic and the first transmission direction of the first directional PRS, respectively; and determining the location of the mobile device based at least in part on the at least one first measurement result, the at least one second measurement result, the first transmission direction of the first directional PRS, and the second transmission direction of the second directional PRS. The at least one cell of the first base station may be a serving cell of the mobile device.At least one of the at least one signal characteristic of the first directional PRS and the first transmit direction may be unique.

[0010] Other and further objects, features, aspects and advantages of the present invention will become better understood from the following detailed description of the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] Figure 1 A diagram of an example communication system.

[0012] Figure 2 Diagram of an example configuration for a beamforming (directional) positioning reference signal (PRS) transmitted from a base station.

[0013] Figure 3A A diagram illustrating an example implementation of using directional (beamforming) PRS signals for position determination functionality.

[0014] Figure 3B A diagram illustrating another example implementation of using directional PRS signals to facilitate position determination functionality.

[0015] Figure 4 A diagram illustrating mitigation of multipath effects using directional PRS signals.

[0016] Figure 5 A signaling flow diagram illustrating messages sent between components of a communication network during a location session.

[0017] Figure 6 FIG. 4 is a diagram of the structure of an example LTE subframe sequence when PRS positioning occurs.

[0018] Figure 7 A diagram illustrating further aspects of PRS transmission for a cell supported by a wireless node.

[0019] Figure 8 is a flow chart of an example procedure typically performed at a network node to support and facilitate positioning of a mobile device.

[0020] Fig. 9 is a flow diagram of an example procedure typically performed at a mobile device to facilitate positioning of the mobile device.

[0021] Fig.10 is a flow chart of an example procedure typically performed at a location-positioning-capable device to facilitate location positioning of a mobile device.

[0022] Fig.11 is a schematic diagram of an example wireless node (eg, a base station, an access point, or a server).

[0023] Fig.12is a schematic diagram of a mobile device (eg UE).

[0024] According to certain example embodiments, similar reference symbols in the various drawings indicate similar elements. In addition, multiple instances of an element may be indicated by following the first number of the element with a hyphen and a second number or by a letter. For example, multiple instances of element 110 may be represented as 110-1, 110-2, 110-3, etc. and / or 110a, 110b, 110c, etc. When only the first number is used to refer to this element, any instance of the element will be understood (e.g., element 110 in the previous example will refer to elements 110-1, 110-2 and 110-3 and / or 110a, 110b and 110c). DETAILED DESCRIPTION

[0025] Obtaining the location or positioning of a mobile device that is accessing a wireless network may be useful for many applications, including, for example, emergency calls, personal navigation, asset tracking, locating friends or family members, etc. Existing positioning methods include methods based on measuring radio signals transmitted from a variety of devices, including satellite vehicles (SVs) and terrestrial radio sources (such as base stations and access points) in wireless networks. In methods based on terrestrial radio sources, a mobile device may measure the timing of signals received from two or more base stations and determine signal strength, arrival time, arrival time difference, and / or reception time-transmission time difference. Combining these measurements with the known locations of the base stations and the known transmission times from each base station may enable the positioning of the mobile device using such positioning methods as observed time difference of arrival (OTDOA) or enhanced cell ID (ECID). Such terrestrial-based positioning methods may be used for wireless networks supporting different wireless technologies, such as long-term evolution (LTE) and fifth generation (5G) (also referred to as new radio (NR)) as defined by an organization called the Third Generation Partnership Project (3GPP).

[0026] Described herein are systems, devices, methods, media, and other implementations for directional positioning reference signals (PRS), also referred to as PRS beamforming. The PRS signal is used to support positioning using, for example, an OTDOA positioning method, and may be transmitted at the same set of times or at different sets of times for different cells in a network. For example, in the case of LTE access, the PRS may be transmitted during a PRS positioning epoch that may occur at fixed periodic intervals, where each positioning epoch includes one or more consecutive subframes (e.g., 1 millisecond duration for each LTE subframe). Cells using the same carrier frequency may be synchronized and use PRS positioning epochs that occur at the same set of times. Although this will typically create interference in the case of other signals, the PRS for any cell may not interfere with (e.g., be orthogonal to) the PRS for any other neighboring cell. This can be achieved using: (i) different sequences of frequency subcarriers across consecutive OFDM symbols in an LTE subframe (referred to as frequency offsets or vshifts); (ii) different PRS code sequences; (iii) different muting sequences, where the PRS location occurrences are muted according to different periodic muting patterns; and / or (iv) different transmission times (e.g., which may be variations of (iii)).

[0027] In the case of LTE or 5G communication technology, the PRS may also be beamformed to not interfere with another PRS (e.g., orthogonal thereto) using, for example, an antenna array at a base station (e.g., an eNodeB for LTE or a gNB for 5G). Using beamforming, a signal (e.g., a PRS) is broadcast within a narrow continuous range of horizontal and / or vertical directions (e.g., a direction having a horizontal span of 5 or 10 degrees (or less or greater)). Transmitting different signals within a small angular range within a cell may also be referred to as spatial multiplexing. Similar to other approaches to suppress or prevent interference from PRSs from different cells, a first directional (beamformed) PRS may not interfere with any other second directional PRS transmitted from the same base station by ensuring that the directions in which the first directional PRS is transmitted are all different from the directions in which the second directional PRS is transmitted. When this non-interference condition is achieved, the transmission direction of the first directional PRS may be considered unique and may be referred to as unique (in the context of transmissions from a given base station). In practice, achieving perfect non-interference may be difficult or impossible due to the presence of side lobes and back lobes, and therefore, when the signal strength of any second directional PRS transmitted by the same base station is substantially weaker (e.g., at least 10 decibels (dB) weaker) in this particular unique direction, the first directional PRS may be deemed and may be referred to as being transmitted in a unique direction.

[0028] In addition to a unique transmission direction, a directional PRS may have other signal characteristics that allow it to be distinguished from another directional PRS and other non-directional PRS (e.g., transmitted throughout the cell coverage area). These other signal characteristics may include a specific carrier frequency, a specific frequency offset (or vshift), a specific PRS code sequence, a specific muting sequence, a specific bandwidth, and / or a specific set of transmission times. One or more of these signal characteristics may be different from the corresponding signal characteristics of other directional PRSs and / or other non-directional PRSs transmitted by the same base station and / or by other neighboring base stations. When a specific first signal characteristic of a first directional PRS is different from the corresponding second signal characteristic of any other second directional PRS transmitted from the same base station and / or from other neighboring base stations, the first signal characteristic may be considered, and may be referred to as unique. When a specific first combination of two or more different signal characteristics of a first directional PRS is different from a second combination of two or more corresponding signal characteristics of any other second directional PRS transmitted from the same base station and / or from other neighboring base stations, the first combination of two or more signal characteristics may be considered, and may be referred to as unique.

[0029] A unique signal characteristic or a unique combination of signal characteristics may enable a directional PRS to be identified by both a mobile device and a positioning-capable device (e.g., a location server). For example, a directional PRS may be defined according to its signal characteristics, which may include a specific unique signal characteristic or a specific unique combination of signal characteristics, and may be further assigned an identifier (ID), such as a PRS ID, a transmission point (TP) ID, or a physical cell ID (PCI). This identifier may also be used to identify a non-directional PRS broadcast throughout a cell, which may avoid the need to define and implement different types of identifiers for directional PRS and non-directional PRS. By detecting and measuring a directional PRS having a given unique signal characteristic or a given unique combination of signal characteristics and a unique identifier, a UE may sense which directional PRS has been measured and may use the unique identifier to identify the directional PRS to a positioning-capable device (e.g., a location server) (e.g., when any measurement results for the directional PRS are provided to the positioning-capable device by the UE).

[0030] The implementation described herein includes a method for supporting positioning of a mobile device (e.g., UE) at a first base station or other processor-based wireless node, wherein the method includes: generating multiple directional PRSs for at least one cell of the first base station, wherein each of the multiple directional PRSs includes at least one signal characteristic and a transmission direction; and transmitting each of the multiple directional PRSs within the at least one cell, wherein each of the multiple directional PRSs is transmitted in the transmission direction. At least one signal characteristic of a specific directional PRS may indicate a respective transmission direction for that specific directional PRS. The transmission direction of the specific directional PRS may be a unique or special direction from a continuous horizontal angle range, a continuous vertical angle range, or a combination thereof. In some embodiments, at least one signal characteristic may include, for example, one or more of a frequency offset, a PRS code sequence, a muting pattern, and / or a transmission time. In some embodiments, transmitting the multiple directional PRSs within the at least one cell may include guiding the multiple directional PRSs via a controllable antenna array configured to beamform each directional PRS in the transmission direction. At least one of the multiple directional PRSs can be detected by the mobile device to facilitate the determination of the position of the mobile device based on an observed time difference of arrival (OTDOA) positioning method, an angle of departure (AOD) positioning method, or an enhanced cell ID (ECID) positioning method, or any combination thereof, at a device with positioning capability (which may be one or more of the first base station, another base station, a mobile device, or a location management function (LMF)).

[0031] Also described herein are systems, devices, methods, media, and other implementations that facilitate positioning of a mobile device, including methods that include: receiving, at a mobile device, a first directional PRS transmitted by a first base station within at least one cell for a first base station, wherein the first directional PRS includes at least one signal characteristic and a transmission direction; and obtaining at least one first measurement of the first directional PRS based at least in part on the at least one signal characteristic. The method further includes facilitating, at a positioning-capable device, a position determination of the mobile device based at least in part on the at least one first measurement. Also disclosed are methods, systems, media, devices, and other implementations, including methods for supporting positioning of a mobile device at a positioning-capable device, wherein the method includes obtaining, from a mobile device, at least one first measurement of a first directional PRS transmitted by a first base station in at least one cell of the first base station, wherein the first directional PRS includes at least one signal characteristic and a transmission direction. The method further includes determining the position of the mobile device based at least in part on the at least one first measurement and the transmission direction. The positioning-capable device may include one or more of a first base station, another base station, a mobile device, and / or a location server (e.g., an LMF).

[0032] Figure 1 A diagram of a communication system 100 according to an embodiment is shown. The communication system 100 may be configured to implement directional PRS transmission and reception. Herein, the communication system 100 includes a user equipment (UE) 105, and components of a fifth generation (5G) network including a next generation (NG) radio access network (RAN) (NG-RAN) 135 and a 5G core network (5GC) 140. A 5G network may also be referred to as a new radio (NR) network; the NG-RAN 135 may be referred to as a 5G RAN or an NR RAN; and the 5GC 140 may be referred to as an NG core network (NGC). Standardization of the NG-RAN and the 5GC is performed in 3GPP. Therefore, the NG-RAN 135 and the 5GC 140 may conform to current or future standards for 5G support from 3GPP. The communication system 100 may further utilize information from a satellite vehicle (SV) 190 of a global navigation satellite system (GNSS), such as GPS, GLONASS, Galileo, or BeiDou, or some other regional or regional satellite positioning system (SPS), such as IRNSS, EGNOS, or WAAS. Additional components of the communication system 100 are described below. The communication system 100 may include additional or alternative components.

[0033] It should be noted that Figure 1 Only a general description of the various components is provided, any or all of which may be utilized as appropriate and each of which may be duplicated or omitted as necessary. In particular, although only one UE 105 is illustrated, it should be understood that many UEs (e.g., hundreds, thousands, millions, etc.) may utilize the communication system 100. Similarly, the communication system 100 may include a greater (or smaller) number of SVs 190, gNBs 110, ng-eNBs 114, AMFs 115, external clients 130, and / or other components. The illustrated connections of the various components in the communication system 100 include data and signaling connections, which may include additional (intermediate) components, direct or indirect physical and / or wireless connections, and / or additional networks. Furthermore, components may be rearranged, combined, separated, replaced, and / or omitted, depending on the desired functionality.

[0034] Although Figure 1A 5G-based network is described, but similar network implementations and configurations may be used for other communication technologies, such as 3G, Long Term Evolution (LTE), etc. The implementations described herein (implementations for 5G technology or for other communication technologies and protocols) may be used to transmit (or broadcast) a directional PRS from a base station (e.g., gNB 110, ng-eNB 114), receive and measure the directional PRS at a UE (e.g., UE 105), and calculate the position of UE 105 at a device with positioning capability (e.g., UE 105, gNB 110, or LMF 120) based on the measurement results for the directional PRS at UE 105.

[0035] UE 105 may include and / or may be referred to as a device, a mobile device, a wireless device, a mobile terminal, a terminal, a mobile station (MS), a secure user plane location (SUPL) enabled terminal (SET), or use some other name. In addition, UE 105 may correspond to a cellular phone, a smart phone, a laptop computer, a tablet computer, a PDA, a tracking device, a navigation device, an Internet of Things (IoT) device, or some other portable or movable device. Typically, but not necessarily, UE 105 supports wireless communications using one or more radio access technologies (RATs), such as Global System for Mobile Communications (GSM), Code Division Multiple Access (CDMA), Wideband CDMA (WCDMA), LTE, High Rate Packet Data (HRPD), IEEE 802.11 WiFi (also known as Wi-Fi), (BT), Worldwide Interoperability for Microwave Access (WiMAX), 5G New Radio (NR) (e.g., using NG-RAN 135 and 5GC 140), etc. UE 105 may also support wireless communications using a wireless local area network (WLAN), which may be connected to other networks (e.g., the Internet) using, for example, a digital subscriber line (DSL) or a package cable. The use of one or more of these RATs may allow UE 105 to communicate with external clients 130 (e.g., via Figure 1 Elements of the 5GC 140 not shown in the figure may communicate via a gateway mobile location center (GMLC) 125) and / or allow the external client 130 to receive (e.g., via the GMLC 125) location information about the UE 105.

[0036] UE 105 may comprise a single entity or may comprise multiple entities, such as in a personal area network where a user may employ audio, video and / or data I / O devices and / or body sensors and separate wired or wireless modems. The estimate of the location of UE 105 may be referred to as location, location estimate, location fix, fix, position, position estimate or position fix, and may be geographic, thus providing location coordinates (e.g., latitude and longitude) of UE 105, which may or may not include an altitude component (e.g., height above sea level, height above ground level or depth below, floor level or basement level). Alternatively, the location of UE 105 may be expressed as an urban location (e.g., a postal address or the name of a certain point or small area (e.g., a specific room or floor) in a building). The location of UE 105 may also be expressed as an area or volume (defined geographically or in the form of a city), within which UE 105 is expected to be located with a certain probability or confidence level (e.g., 67%, 95%, etc.). The location of the UE 105 may further be a relative location, including, for example, distance and direction or relative X, Y (and Z) coordinates defined relative to a certain starting point at a known location, which may be defined geographically or in urban terms or with reference to a point, area, or three-dimensional space indicated on a map, floor plan, or building plan. In the description contained herein, unless otherwise indicated, the use of the term location may include any of these variations. When calculating the location of the UE, the regional x-coordinate, y-coordinate, and possibly z-coordinate are typically solved, and then (if necessary) the regional coordinates are converted to absolute coordinates (e.g., latitude, longitude, and altitude above or below mean sea level).

[0037] Shown in Figure 1 The base stations (BSs) in the NG-RAN 135 in the NG-RAN 135 include NR Node Bs also referred to as gNBs 110-1 and 110-2 (collectively and generally referred to herein as gNB 110). The number of gNBs 110 in the NG-RAN 135 may be, for example, Figure 1 105 are directly or indirectly connected to each other via other gNBs 110 as shown in FIG. 106 . Access to the 5G network is provided to UE 105 via wireless communications between UE 105 and one or more of gNBs 110, which can provide wireless communication access to the 5G GC using 5G on behalf of UE 105. Figure 1 , the serving gNB for UE 105 is assumed to be gNB 110-1, but other gNBs (e.g., gNB 110-2) may act as serving gNBs when UE 105 moves to another location or they may act as secondary gNBs to provide additional throughput and bandwidth to UE 105.

[0038] Figure 1The base stations (BS) in the NG-RAN 135 shown in FIG. 1 may also include a next generation evolved Node B, also referred to as ng-eNB 114. Ng-eNB 114 may be, for example, Figure 1 105. The ng-eNB 114 is shown as being connected to one or more gNBs 110 in the NG-RAN 135 directly or indirectly via other gNBs 110 and / or other ng-eNBs. The ng-eNB 114 can provide LTE radio access and / or evolved LTE (eLTE) radio access to the UE 105. Figure 1 Some gNBs 110 (e.g., gNB 110-2) and / or ng-eNBs 114 may be configured to act as positioning-only beacons, which may transmit signals (e.g., directional PRS) to assist in positioning of UE 105 but may not receive signals from UE 105 or from other UEs.

[0039] As mentioned, although Figure 1 Nodes configured to communicate according to a 5G communication protocol are depicted, but nodes configured to communicate according to other communication protocols (e.g., an LTE protocol or an IEEE 802.11x protocol) may be used. For example, in an evolved packet system (EPS) that provides LTE radio access to UE 105, the RAN may include an evolved universal mobile telecommunications system (UMTS) terrestrial radio access network (E-UTRAN), which may include base stations including evolved Node Bs (eNBs). The core network for the EPS may include an evolved packet core (EPC). The EPS may then include the E-UTRAN plus the EPC, where Figure 1 E-UTRAN corresponds to NG-RAN 135 and EPC corresponds to 5GC 140. The methods and techniques described herein for supporting UE 105 positioning using directional PRS may be applicable to such other networks, such as for directional PRS transmissions from eNBs and / or from WiFi IEEE 802.11 access points (APs).

[0040] The gNB 110 and ng-eNB 114 may communicate with an access and mobility management function (AMF) 115, which in turn communicates with a location management function (LMF) 120 for positioning functionality. The AMF 115 may support mobility of the UE 105, including cell changes and handovers, and may participate in supporting signaling connections to the UE 105 and possibly data and voice bearers for the UE 105. The LMF 120 may support positioning of the UE 105 while the UE accesses the NG-RAN 135, and may support positioning procedures / methods such as Assisted GNSS (A-GNSS), Observed Time Difference of Arrival (OTDOA), Real Time Kinematic (RTK), Precise Point Positioning (PPP), Differential GNSS (DGNSS), Enhanced Cell ID (ECID), Angle of Arrival (AOA), Angle of Departure (AOD), and / or other positioning methods. LMF 120 may also process location service requests for UE 105, such as those received from AMF 115 or from GMLC 125. LMF 120 may be connected to AMF 115 and / or GMLC 125. LMF 120 may be referred to by other names, such as location manager (LM), location function (LF), commercial LMF (CLMF), or value-added LMF (VLMF). In some embodiments, a node / system implementing LMF 120 may additionally or alternatively implement other types of location support modules, such as an enhanced serving mobile location center (E-SMLC) or a secure user plane location (SUPL) location platform (SLP). It should be noted that in some embodiments, at least part of the positioning functionality (including derivation of the location of UE 105) may be performed at UE 105 (e.g., using signal measurements obtained by UE 105 for signals transmitted by wireless nodes (e.g., gNB 110 and ng-eNB 114), and assistance data provided to UE 105, such as by LMF 120).

[0041] A gateway mobile location center (GMLC) 125 may support location requests for UE 105 received from an external client 130, and may forward such location requests to AMF 115 for forwarding to LMF 120 through AMF 115, or may forward the location requests directly to LMF 120. A location response (e.g., containing a location estimate for UE 105) from LMF 120 may similarly be transmitted back to GMLC 125 directly or via AMF 115, and GMLC 125 may then transmit back a location response (e.g., containing a location estimate) to the external client 130. GMLC 125 is shown as being connected to both AMF 115 and LMF 120, but only one of such connections may be supported by 5GC 140 in some implementations.

[0042] like Figure 1 As further described in , LMF 120 may communicate with gNB 110 and / or ng-eNB 114 using a new radio position protocol A (which may be referred to as NPPa or NRPPa), which may be defined in 3GPP Technical Specification (TS) 38.455. NRPPa may be the same as, similar to, or an extension of LTE Positioning Protocol A (LPPa) defined in 3GPP TS 36.455, where NRPPa messages are transferred between gNB 110 and LMF 120 and / or between ng-eNB 114 and LMF 120 via AMF 115. Figure 1 As further described in 3GPP TS 36.355, LMF 120 and UE 105 may communicate using the LTE Positioning Protocol (LPP), which may be defined in 3GPP TS 36.355. LMF 120 and UE 105 may also or may actually communicate using a new radio positioning protocol (which may be referred to as NPP or NRPP), which may be the same as, similar to, or an extension of LPP. Herein, LPP and / or NPP messages may be transferred between UE 105 and LMF 120 via AMF 115 and serving gNB 110-1 or serving ng-eNB 114 for UE 105. For example, LPP and / or NPP messages may be transferred between LMF 120 and AMF 115 using a 5G Location Services Application Protocol (LCS AP) and may be transferred between AMF 115 and UE 105 using a 5G Non-Access Stratum (NAS) protocol. The LPP and / or NPP protocols may be used to support positioning of UE 105 using UE-assisted and / or UE-based positioning methods (e.g., A-GNSS, RTK, OTDOA, and / or ECID). The NRPPa protocol may be used to support positioning of UE 105 using network-based positioning methods (e.g., ECID) (e.g., when used with measurements obtained by gNB 110 or ng-eNB 114) and / or may be used by LMF 120 to obtain location-related information from gNB 110 and / or ng-eNB 114, such as parameters defining PRS transmissions from gNB 110 and / or ng-eNB 114.

[0043] Using the UE-assisted positioning method, UE 105 may obtain location measurements and send the measurements to a location server (e.g., LMF 120) for use in calculating a location estimate of UE 105. For example, the location measurements may include one or more of a received signal strength indication (RSSI), a round trip signal propagation time (RTT), a reference signal time difference (RSTD), a reference signal received power (RSRP), and / or a reference signal received quality (RSRQ) for gNB 110, ng-eNB 114, and / or WLAN AP. The location measurements may also or may actually include measurements of GNSS pseudoranges, code phase, and / or carrier phase for SV 190. Using the UE-based positioning method, UE 105 may obtain location measurements (e.g., which may be the same or similar to location measurements of the UE-assisted positioning method) and may calculate the location of UE 105 (e.g., with the aid of assistance data received from a location server (e.g., LMF 120) or broadcast by gNB 110, ng-eNB 114, or other base stations or APs). Using a network-based positioning method, one or more base stations (e.g., gNB 110 and / or ng-eNB 114) or APs may obtain location measurement results (e.g., measurements of RSSI, RTT, RSRP, RSRQ, or time of arrival (TOA) of a signal transmitted by UE 105) and / or may receive measurement results obtained by UE 105, and may send the measurement results to a location server (e.g., LMF 120) for calculating a location estimate of UE 105.

[0044] The information provided to LMF 120 using NRPPa by gNB 110 and / or ng-eNB 114 may include timing and configuration information and location coordinates for directional PRS transmissions. LMF 120 may then provide some or all of this information to UE 105 via NG-RAN 135 and 5GC 140 as assistance data in LPP and / or NPP messages.

[0045] Depending on the desired functionality, the LPP or NPP message sent from LMF 120 to UE 105 may direct UE 105 to perform any of a variety of things. For example, the LPP or NPP message may contain instructions for UE 105 to obtain measurements for GNSS (or A-GNSS), WLAN, and / or OTDOA (or some other positioning method). In the case of OTDOA, the LPP or NPP message may direct UE 105 to obtain one or more measurements (e.g., RSTD measurements) of PRS signals and / or directional PRS signals transmitted within a particular cell supported by a particular gNB 110 and / or ng-eNB 114 (or supported by some other type of base station, such as an eNB or WiFi AP). UE 105 may send the measurements back to LMF 120 in an LPP or NPP message (e.g., inside a 5G NAS message) via serving gNB 110-1 (or serving ng-eNB 114) and AMF 115.

[0046] As mentioned, although the communication system 100 is described with respect to 5G technology, the communication system 100 may be implemented to support other communication technologies for supporting mobile devices (e.g., UE 105) and interacting with the mobile devices (e.g., to implement voice, data, positioning, and other functionalities), such as GSM, WCDMA, LTE, etc. In some such embodiments, the 5GC 140 may be configured to control different air interfaces. For example, in some embodiments, the 5GC 140 may use the non-3GPP interworking function (N3IWF, Figure 1115). The 5GC 140 may be connected to the WLAN by the NG-RAN 135 (not shown). For example, the WLAN may support IEEE 802.11 WiFi access for the UE 105 and may include one or more WiFi APs. In this document, the N3IWF may be connected to the WLAN and other elements in the 5GC 150 (e.g., AMF 115). In some other embodiments, both the NG-RAN 135 and the 5GC 140 may be replaced by other RANs and other core networks. For example, in the EPS, the NG-RAN 135 may be replaced by an E-UTRAN containing eNBs and the 5GC 140 may be replaced by an EPC containing a mobility management entity (MME) instead of the AMF 115, an E-SMLC instead of the LMF 120, and a GMLC that may be similar to the GMLC 125. In this EPS, the E-SMLC may use LPPa instead of NRPPa to send location information to and receive location information from the eNBs in the E-UTRAN and may use LPP to support positioning of the UE 105. In these other embodiments, positioning of UE 105 using directional PRS may be supported in a manner similar to that described herein for 5G networks, where the differences in functionality and procedures described herein for gNB 110, ng-eNB 114, AMF 115, and LMF 120 may in some cases actually be applied to other network elements, such as eNBs, WiFi APs, MMEs, and E-SMLCs.

[0047] As mentioned, in some embodiments, positioning functionality may be implemented at least in part using PRS transmissions and / or directional PRS transmissions sent by a base station (e.g., gNB 110 and / or ng-eNB 114) within the range of a UE, the UE (e.g., Figure 1 The location of the UE 105) will be determined. In some cases, the UE may use the difference in arrival time of downlink radio signals (e.g., directional PRS transmissions) from multiple base stations (e.g., gNB 110, ng-eNB 114, etc.) to calculate the location of the UE. For example, if the signal from one base station arrives at time t 1 and the signal from another base station is received at time t 2 If it is received at 2 -t 1 Calculate OTDOA or RSTD.

[0048] Figure 2 An example configuration 200 illustrates directional PRS transmission (or PRS beamforming) at a base station 202 (represented by small solid circles) supporting three (3) cell sectors A (labeled as sector 210), B (labeled as sector 220), and C (labeled as sector 230). The base station 202 may communicate with Figure 1Any of the gNB 110 or ng-eNB 114 in the UE may be similar or identical thereto, or may be some other base station (e.g., eNB) or a WiFi AP. Each cell sector (also referred to herein as a cell) has a coverage area. Figure 2 In the example description of , the coverage area is a circular sector with a central angle of 120 degrees. Figure 2 In the example of , within each cell sector, six (6) separate directional PRS signals may be broadcast on (approximately) non-overlapping circular sectors at a center angle of 20 degrees each. Other sector configurations and proportional allocations for directional PRS signals may be implemented, with controllable beamwidth and beam shape characteristics based on the antenna configuration implemented for base station 202. Figure 2 The individual directional PRS signals in are labeled An, Bn, and Cn, where in this example 1≤n≤6. To distinguish the individual directional PRS signals An, Bn, and Cn (e.g., so that the UE and / or location server can determine which directional PRS signal the UE is measuring) and / or to reduce interference, the directional PRS signals may be orthogonalized in various ways as previously described (e.g., by assigning a different (or unique) vshift value, a different (or unique) PRS code sequence, a different (or unique) muting pattern, a different (or unique) set of transmission times, or a different (or unique) combination of two or more of such signal characteristics to each directional PRS).

[0049] Figure 2 The directional PRSs shown in each span a continuous horizontal angle (or horizontal direction) range within each circular sector with a coverage of 20 degrees in the horizontal plane. Figure 2 Each directional PRS shown in may also span a continuous but finite range of vertical angles (or vertical directions), such as angles ranging from zero degrees (which may coincide with the horizontal direction) to 20 degrees (which may coincide with the direction rising to the horizontal at 20 degrees). In addition, there may be shareable Figure 2 Other directional PRS signals with the same horizontal angle range shown in FIG. 1 but with different vertical angle ranges, Figure 2 As an example, for Figure 2 For each directional PRS shown in , there may be one directional PRS with an elevation angle between zero and 20 degrees ( Figure 2 ), another directional PRS with an elevation angle between 20 and 40 degrees ( Figure 2 ) and a third directional PRS (not shown) having an elevation angle between 40 and 60 degrees Figure 22 (not shown), where each of these directional PRSs has the same horizontal angle range. In another example, the directional PRS signals may not be horizontal (e.g., may be transmitted throughout the coverage area of ​​a particular cell) but may have a different vertical angle range. Control of the directional PRS signals transmitted by the antenna array for base station 202 may be performed by, for example, selecting individual antennas (or individual antenna elements) of the antenna array of base station 202 to transmit signals, controlling the relative phases and amplitudes of the signals directed through the various selected antennas (or antenna elements) of the array, etc.

[0050] Processing of directional PRS signal Pn in any cell sector P (eg, where P represents Figure 2 A convenient way to process each directional PRS signal as corresponding to a different transmitter or a different cell (e.g., one of A, B, or C in ), for example, as if each directional PRS signal Pn was transmitted through a different antenna (e.g., an antenna associated with a different remote radio device head for cell sector P). The directional PRS signal Pn may then be assigned a different PRS ID associated with a different PRS code sequence and / or a different vshift for the directional PRS signal Pn. In some embodiments, the directional PRS signal may be assigned a different transmission point ID. For LTE access by UE 105, this would allow a location server (e.g., E-SMLC, SUPL SLP, or LMF, such as LMF 120) to provide assistance data to UE 105 using existing capabilities in the LPP for directional PRS signal Pn. The assistance data may make the UE 105 aware of the presence of directional PRS signals and signal characteristics and other parameters for each directional PRS signal (e.g., PRSID, transmission point ID, carrier frequency, bandwidth, number of positioning epochs and subframes, muting pattern, expected RSTD measurement results, etc.) and allow the UE 105 to perform RSTD measurements for OTDOA positioning. This support may not require any changes to the LPP (or NPP) since the location server may treat each directional PRS Pn as the same as the PRS transmitted by a different radio head or a different distributed antenna system (DAS) antenna for a cell sector P (as already supported in the LPP).

[0051] In some embodiments, two or more different directional PRS signals Pn may be transmitted by base station 202 simultaneously but in a manner that allows any PRS signal Pi to be distinguished from any other PRS signal Pj by UE 105 (e.g., by using different frequencies, different frequency offsets, or different PRS code sequences). In another embodiment, one PRS signal may be transmitted by base station 202 in a cell (e.g., cell A, B, or C) at different non-overlapping times in different directions using beamforming. For example, for Figure 2The base station 202 of cell sector A in the cell sector A may use beamforming to transmit a directional PRS signal in time interval T1 in a direction that coincides with directional PRS A1, then may change the direction of the PRS signal transmission in time interval T2 to coincide with directional PRS A2, and may then change the direction of the directional PRS signal transmission in time intervals T3, T4, T5, and T6 to coincide with directional PRS signals A3, A4, A5, and A6, respectively. If the time intervals T1, T2, ... T6 do not substantially overlap, then there may be no ambiguity about which directional PRS signal the UE 105 has measured if the time intervals during which the directional PRS signals are measured can be obtained and compared with the known transmission intervals T1, T2, ... Tn. In addition, the order in which the angles of the directional PRS transmissions are changed in the cell may vary, for example, any transformation of the angles (transmitted relative to a reference point or reference line) that are changed to correspond to different PRS signals A1, A2, ... A6. For example, in one embodiment, the base station 202 may change the angle of the directional PRS transmission in a cyclic manner (e.g., by transmitting the directional PRS signal in the order of A1, A2, ... A6 or in the reverse order) and / or may rotate the directional PRS transmission in a circular manner (e.g., by transmitting the directional PRS signal in the order of A1, A2, ... A6 followed by B1, B2, ... B6 and then followed by C1, C2, ... C6). The UE 105 measuring the PRS signal of cell sector A may use the timing information included as one party of the directional PRS signal or use the timing information sent independently via another signal (e.g., an omnidirectional cell-specific reference signal) transmitted for cell sector A, or by using the timing information transmitted via different cells S (e.g., Figure 2 The measurement time may be determined based on the timing acquisition time provided by the serving cell for UE 105 (e.g., cell sector B or cell sector C in the example above) or the serving cell for UE 105 (in the case different from cell sectors A, B, and C). In the latter case, if the timing difference between cells A and S is known (e.g., due to synchronizing the transmit timing of cells A and S using GPS or GNSS, or determining the transmit timing of cells A and S with respect to GPS or GNSS), then the measurement time with respect to the directional PRS signal of cell S may be used to determine the measurement time with respect to cell sector A, and therefore which directional PRS signal to measure.

[0052] There are several ways by which directional PRS signals can be used for position determination (e.g., to perform OTDOA positioning) of UE 105. In a first example, directional PRS signals can be used to obtain guidance information about the location of UE 105. For example, if UE 105 is able to receive and measure Figure 2 If directional PRS A5 is located in cell sector A, then UE 105 is determined to be within the coverage area of ​​directional PRS A5 and not elsewhere in the coverage area of ​​cell sector A. This can be used to improve the accuracy of the UE location.

[0053] Figure 3A A diagram 300 is shown illustrating the use of directional (beamforming) PRS signals for position determination functionality. In this example, a UE 105 (not shown) measures or detects, for example, Figure 2 UE 105 can measure / detect another directional PRS signal, namely PRS D2 transmitted from another cell D having an antenna position different from that of cell sector A. For example, cell D can be detected by Figure 1 104 is supported by a gNB 110 (or ng-eNB 114) in cell sector A, which may be different from the gNB 110 supporting cell sector A. UE 105 may then infer that Figure 3A 3. Within the intersection region 310 of the two directional PRS beams shown in FIG. Figure 3A The example in may be referred to as positioning based on the angle of departure (AOD) positioning method.

[0054] according to Figure 3A The position determination may be performed at a positioning-capable device that knows the positions of the base station antennas of cells A and D and the precise directions of the directional PRSs A5 and D2. For example, the positioning-capable device may be a base station of cell A, a base station of cell D, LMF 120, or UE 105 (e.g., when UE 105 is provided with the positions of the base station antennas of cells A and D and the precise directions of the directional PRSs by another entity (e.g., a serving base station or LMF 120).

[0055] Figure 3B Included is a diagram 320 showing another example implementation of using directional PRS signals to facilitate position determination functionality. Figure 3B In the example, UE 105 (not shown) measures / detects Figure 2 PRS A5. In this article, UE 105 and / or gNB 110 (or some other wireless node, such as ng-eNB 114) for cell A measures the signal propagation time or round-trip signal propagation time (RTT) between UE 105 and the antenna of cell A. If RTT has a measurement value of 2T plus or minus uncertainty U, then the distance between the UE and the antenna for cell A will be given by (Tc) with uncertainty (Uc), where c is the speed of light and line of sight (LOS) transmission is assumed. In this example, the UE 105 can be determined to be located at a certain location based on the identity of the specific directional PRS detected by UE 105 and the measured timing information (such as RTT). Figure 3B In the area 330 depicted in FIG. Figure 3B The example in may be referred to as enhanced cell ID (ECID) based positioning.

[0056] according to Figure 3B The position determination may be performed at a device with positioning capabilities that knows the position of the base station antenna for cell A, the precise direction of the directional PRS A5, and the measured RTT and its uncertainty. For example, the device with positioning capabilities may be the base station for cell A, LMF 120, or UE 105 (e.g., when UE 105 is provided with the position of the base station antenna for cell A, the precise direction of the directional PRS A5, and optionally information that assists in RTT determination by another entity (e.g., another entity of the base station for cell A)).

[0057] In another example implementation, directional (beamforming) PRS may be used to reduce erroneous / inaccurate positioning due to measurements of multipath signals. In multipath situations, signals transmitted in a cell may experience reflection, refraction, and / or scattering from one or more surfaces, objects (e.g., walls and roofs of buildings), or materials (e.g., water, air) such that the signal received by a UE may not be a line-of-sight (LOS) signal, but rather some redirection of a signal transmitted from a source that may or may not be in the UE's LOS. This will generally increase the signal propagation time to the UE compared to any LOS signal resulting in errors for time-based positioning methods (e.g., OTDOA).

[0058] Figure 4 4 includes diagram 400 illustrating two signals, namely S1 (labeled as signal 412) and S2 (labeled as signal 414) arriving at a UE 420 in a cell supported by a base station 410. The UE 420 may communicate with Figure 1 The base station 410 may be similar or identical to the UE 105 of FIG. Figure 1 The LTE-enabled gNB 110 or ng-eNB 114 may be similar or identical to any of the gNBs 110 or ng-eNB 114, or some other base station (e.g., an eNB supporting LTE communications), or some other node or access point. Figure 4 In the example depicted in FIG. 4 , signal S1 is a LOS signal received directly from base station 410, while signal S2 is a multipath signal (also referred to as a non-LOS (NLOS) signal) caused by reflections of signal 416 originating from base station 410. Since multipath (NLOS) signal S2 does not travel completely in a straight line to the UE, it will typically initially travel from a cell antenna in a different direction than signal S1, such as Figure 4 Thus, if a cell uses directional PRS, then signals S1 and S2 will typically correspond to different directional PRS signals (e.g., if the beam angle is narrow enough). For example, if the cell served by base station 410 corresponds to Figure 2The location server (or UE 420) knowing the estimated location of UE 420 can thus guide UE 420 to measure signal S1 (e.g., signal S2) by providing assistance data only for signal S1. Figure 2 Directional PRSA3 in the example) without directing UE 420 to measure signal S2 (e.g. Figure 2 directional PRS A2 or A4 in the directional PRS. This will prevent or inhibit UE 420 from measuring multipath signals and improve the chance of measuring LOS signals. Because different directional PRS signals may be associated with different (or unique) signal characteristics (e.g., different PRS IDs, different frequency offsets (vshift), different PRS code sequences, different muting patterns, different transmission times, etc.) in some embodiments, UE 420 may therefore be configured to measure a particular signal characteristic value (e.g., a particular PRS code sequence or a particular vshift value) or a particular combination of signal characteristic values ​​(e.g., a particular PRS code sequence value and a particular vshift value) that is consistent with an expected LOS directional PRS signal (e.g., Figure 4 The signal S1 412 or Figure 2 However, UE 420 may not be configured to measure (or may be configured not to measure) a LOS that is not expected to be associated with some other signal characteristic value or some other combination of signal characteristic values ​​(e.g., Figure 2 Directional PRS signal in A2 or A4).

[0059] In another aspect, the UE 105 may have multiple antennas (e.g., antenna arrays) that allow the UE 105 to selectively receive and measure signals arriving from a particular direction and filter out and ignore signals arriving from other directions. The location server (e.g., LMF 120) may provide the transmission direction for the LOS signal S1 412 to the UE 105 but may not provide information for the NLOS signal S2 414 / 416. The UE 105 may then use multiple antennas (e.g., antenna arrays) to receive and measure signals having the same transmission direction as the signal S1, which may enable the UE 105 to measure the TOA or RSTD (or other signal characteristics) of the signal S1. Using multiple antennas or antenna arrays at the UE 105 to tune to reception of a particular transmission direction may reduce interference from other signals (e.g., signal S2) to the signal S1 and may enable improved acquisition and higher measurement accuracy of the signal S1 by the UE 105.

[0060] Directional (beamforming) PRS signals may also be used to reduce multipath effects in situations where the location server (or UE 420) may not have an estimated location of UE 420, or may not provide information for only LOS signals to UE 420. In this case, the location server (or UE 420) may receive (or obtain) multipath signals (e.g., Figure 4 Some measurement results of the signal S2414 in (such as OTDOARSTD measurement results) and LOS signals (such as Figure 4 The location server (or UE 420) may use all the measurement results provided (or obtained) by the UE 420 to obtain the initial location of the UE 420. The location server (or UE 420) may then identify the directional PRS signals whose coverage area does not include the determined location and tentatively identify these signals as multipath signals. The location server (or UE 420) may then use the measurement results of only the signals that are not identified as multipath signals to re-determine the UE 420 location. The process may be repeated by again identifying the directional PRS signals whose coverage area does not include the new location and processing these as multipath signals. The directional PRS signals that were initially tentatively identified as multipath signals may no longer need to be identified as multipath signals if the new UE 420 location is now within its coverage area. A variation of this example procedure may also be used in the case where the location determination procedure uses the direction information as well as the RSTD measurement results to determine the initial (and any subsequent) UE 420 location.

[0061] In another aspect, UE 420 may measure the angle of arrival (AOA) of the directional PRS and other characteristics such as TOA and / or RSTD. If the AOA measured by UE 420 is consistent with (e.g., equal to or approximately equal to) the transmission direction of the measured directional PRS, then UE 420 or a device with positioning capabilities (e.g., E-SMLC or LMF 120) may assume that the directional PRS measured by UE 420 is LOS (e.g., is Figure 4 In contrast, if the AOA measured by the UE 420 is not consistent with the transmission direction of the measured directional PRS (e.g., not equal to or approximately equal to the transmission direction of the measured directional PRS), the UE 420 or a device with positioning capabilities (e.g., an E-SMLC or LMF 120) may assume that the directional PRS measured by the UE 420 is NLOS or multipath (e.g., Figure 4 signal S2 414 / 416 in ).

[0062] When, for example, UE 105 provides measurement results of directional PRS to a device with positioning capabilities (e.g., gNB 110, ng-eNB 114, or LMF 120) for determining the position of UE 105, reference is made to Figure 3A , 3B The above example embodiments discussed in part 4 and 4 may be used to improve the position determination of UE 105 with respect to UE-assisted OTDOA. Embodiments may also be used to improve the position determination of UE 105 with respect to UE-based OTDOA when, for example, a network (e.g., gNB 110 or ng-eNB 114) or a location server (e.g., LMF 120) provides information about directional PRS (e.g., directional PRS transmission direction and signal characteristics) as well as base station coordinates and other PRS parameters to UE 105. For example, for UE-assisted OTDOA or UE-based OTDOA, Figure 1 A gNB 110 or ng-eNB 114 in the communication system 100 may broadcast information about a directional PRS transmitted by this gNB 110 or ng-eNB 114 and possible directional PRS transmitted by other neighboring gNBs 110 and / or ng-eNBs 114.

[0063] Figure 5 And further reading Figure 1 A signaling flow 500 is shown that illustrates a signaling flow between a UE 105 and a location server corresponding to an LMF 120 during a location session using LPP and / or NPP (also referred to as an LPP / NPP session) over a communication network (e.g., Figure 1 Various messages sent between components of the communication system 100 depicted in . When discussing the signaling process 500, for ease of explanation, with respect to a 5G communication network implementation, similar messaging may be implemented for other communication technologies or protocols (e.g., EPS or WLAN). In addition, in some embodiments, the UE 105 itself may be configured to determine its position using, for example, auxiliary data provided to the UE 105 (e.g., by the LMF 120 or by the serving gNB 110-1). The positioning protocol used for the signaling process 500 may be LPP, NPP, or LPP combined with NPP (e.g., where the LPP message includes an embedded NPP message). Messages for the positioning protocol are therefore referred to below as LPP / NPP messages to indicate that the messages are for LPP, NPP, or LPP combined with NPP. However, other positioning protocols are also possible, such as the LPP extension (LPPe) protocol defined by the Open Mobile Alliance (OMA).

[0064] In some embodiments, when LMF 120 receives a location request for UE 105 at action 501, a location session for UE 105 may be triggered. Depending on the situation, the location request to LMF 120 may come from AMF 115 or from Figure 1 105. The LMF 120 may then query the AMF 115 for information about the UE 105. The AMF 115 may then send the information about the UE 105 to the LMF 120 ( Figure 5 The information may indicate that the UE 105 has 5G (or LTE or eLTE) radio access capability (for Figure 5 105) and may provide the current 5G serving cell for UE 105 (e.g., cells supported by gNB 110-1, which may be a serving gNB for UE 105) and / or may indicate that UE 105 supports location using LPP and / or NPP. For example, some or all of this information may have been obtained from UE 105 and / or from gNB 110-1 via AMF 115 when UE 105 attached to and registered with 5GC 140.

[0065] To start an LPP / NPP session (e.g., and based on an indication that UE 105 supports LPP and / or NPP using a 5G radio access), LMF 120 sends an LPP / NPP request capability message to AMF 115 serving UE 105 (e.g., using a 5G LCS AP) at action 502. AMF 115 may include the LPP / NPP request capability message in a 5G NAS transport message, which is sent to UE 105 (e.g., via a NAS communication path in NG-RAN 135, such as 5G NAS transport message) at action 503. Figure 1). At action 504, the UE 105 responds to the AMF 115 with an LPP / NPP Provide Capability message also within the 5G NAS transport message. The AMF 115 extracts the LPP / NPP Provide Capability message from the 5G NAS transport message and relays the LPP / NPP Provide Capability message to the LMF 120 (e.g., using a 5G LCS AP) at action 505. Herein, the LPP / NPP Provide Capability message sent at actions 504 and 505 may indicate the positioning capabilities of the UE 105 when accessing the 5G network, for example, the positioning methods and associated assistance data supported by the UE 105 (e.g., A-GNSS positioning, OTDOA positioning, ECID positioning, WLAN positioning, etc.). In the case of some positioning methods (e.g., OTDOA positioning), the capability may indicate whether the UE 105 is capable of measuring or improving the measurement results of directional PRS signals. For example, the capability may indicate that the UE 105 is capable of using multiple antennas to adjust to PRS reception of a specific expected direction of arrival of the directional PRS. However, in an aspect, the UE 105 may acquire and measure directional PRS in the same manner as non-directional PRS (e.g., PRS transmitted throughout the entire cell coverage area) and may not need to know whether the PRS is directional PRS or non-directional PRS. In this aspect, the capability may not indicate that the UE supports directional PRS.

[0066] Based on the positioning capabilities of UE 105 received at act 505 and possibly based on the location request received at act 501 (e.g., the location accuracy requirement included in the location request received at act 501), LMF 120 may select one or more positioning methods at act 506 to locate UE 105. For example, LMF may select OTDOA and / or ECID at act 506 in conjunction with a directional PRS transmitted from gNB 110 and / or from ng-eNB 114.

[0067] Based on the positioning method selected at action 506 and the assistance data indicated as supported by UE 105 at action 505, LMF 120 may determine that the assistance data for UE 105 supports the selected positioning method. LMF 120 may then send an NRPPa information request message at action 507, which may be relayed to serving node gNB 110-1 (at action 508) via AMF 115. The NRPPa information request may request location-related information for gNB 110-1, such as the location of gNB 110-1, PRS configuration parameters for gNB 110-1, and / or information about broadcasting of assistance data by gNB 110-1. The NRPPa information request sent at actions 507 and 508 may include a request for configuration parameters related to directional PRSs (e.g., a request for a transmission direction, horizontal angle range, vertical angle range, and / or other signal characteristics of each directional PRS transmitted by gNB 110-1). The serving node gNB 110-1 responds at action 509 with an NRPPa information response message, which may be relayed to the LMF 120 via the AMF 115 at action 510. The NRPPa information response may provide some or all of the location-related information requested at actions 507 and 508. For example, when configuration parameters for PRS and / or directional PRS are requested at actions 507 and 508, the NRPPa information response may provide signal characteristics and other configuration information for each PRS and / or each directional PRS supported by the gNB 110-1. In the case of directional PRS, the provided information may include transmission direction, horizontal angle range, vertical angle range, and / or other signal characteristics (e.g., carrier frequency, frequency offset (or vshift), bandwidth, code sequence, period of a fix epoch, duration of a fix epoch, and / or muting sequence). Actions 507 to 510 may be repeated by LMF 120 to obtain the UE 105 from other gNBs 110 and / or ng-eNBs (e.g., gNB 110-2 and ng-eNB 114) adjacent to UE 105. Figure 5 (not shown)) obtain location-related information (such as configuration parameters for directional PRS).

[0068] In some implementations, serving gNB 110-1 and / or other gNBs 110 and ng-eNBs (e.g., gNB 110-2 and ng-eNB 114 ( Figure 5 5G access protocol (not shown)) may broadcast the assistance data to UE 105 (and to other UEs) at action 511 and / or may be provided in a point-to-point manner (e.g., using the radio resource control protocol (RRC) for 5G access) ( Figure 5512 and 513). In some embodiments, the broadcast may use a system information block (SIB) for the RRC protocol. The assistance data may include configuration parameters and signal characteristics for PRS signals and / or directional PRS signals transmitted by the sending gNB 110 and / or transmitted by other neighboring gNBs 110 and / or ng-eNBs 114. The configuration parameters and signal characteristics for the PRS signals and / or directional PRS signals broadcast by gNB 110-1 (and / or by other gNBs 110 and / or ng-eNBs 114) may be the same as the configuration parameters and signal characteristics for the PRS signals and / or directional PRS signals further described below for the location-related information sent at actions 512 and 513. In some embodiments, for example, where all location-related information may be broadcast to UEs by gNB 110-1 and / or by other gNBs 110 and / or ng-eNBs 114, actions 512 and 513 as described below may not occur.

[0069] LMF 120 may send some or all of the assistance data received at action 510 and possible other assistance data already known to LMF 120 to UE 105 via an LPP / NPP Provide Assistance Data message sent to AMF 115 at action 512 and relayed by AMF 115 to UE 105 in a 5G NAS Transport message at action 513. In the case of OTDOA positioning, the assistance data may include identification codes of reference cells and neighboring cells supported by gNB 110 and / or by ng-eNB 114 and may include information for each cell, such as the cell carrier frequency, and configuration parameters for each PRS transmitted within the cell. The assistance data may also include configuration parameters and signal characteristics associated with different directional PRS signals that may be beamformed by the antenna arrays of gNB 110 and / or ng-eNB 114. For example, in such embodiments, the assistance data may include information for each directional PRS transmitted by a reference cell or a neighboring cell, such as a PRS ID, a transmission point ID, a physical cell ID, a code sequence, a muting pattern, a frequency offset (vshift), a period and duration of a positioning epoch, etc. The information for each directional PRS included in the assistance data sent at actions 512 and 513 may be the same as the information included for a non-directional PRS, in which case the assistance data may not identify the directional PRS or provide any different assistance data. However, in one aspect, the assistance data sent by LMF 120 at actions 512 and 513 may include different information for a directional PRS, such as identification of the directional PRS, a transmission direction, a horizontal angle range, and / or a vertical angle range. In some implementations, when the positioning method selected at action 506 includes ECID, OTDOA, and / or other positioning methods (e.g., AOA, AOD, WLAN) measured by UE 105 utilizing directional PRS, information for directional PRS (e.g., the information just described) may be sent by LMF 120 at actions 512 and 513.

[0070] The NAS transport message transmitted at action 513 may be followed by an LPP / NPP request location information message sent again from LMF 120 to AMF 115 at action 514, which is relayed to UE 105 in a 5G NAS transport message by AMF 115 at action 515. The LPP / NPP request location information message may request one or more location measurements from UE 105 and / or a location estimate according to, for example, the positioning method selected at action 506 and / or the positioning capability of UE 105 sent to LMF 120 at actions 504 and 505. The positioning measurement results may, for example, include TOA measurement results for OTDOA or ECID, RSTD measurement results for OTDOA, measurement results of AOA, RTT, RSRP, RSRQ, and / or one-way signal propagation delay for ECID, etc. Some of the positioning measurements may be further specified or allowed to be measured for directional PRS (eg, directional PRS whose configuration parameters and signal characteristics may have been provided as previously described for actions 511, 512, and 513).

[0071] At act 516, the UE 105 may then obtain some or all of the location measurements (and other information) requested at acts 514 and 515. The location measurements may be obtained based in part on directional PRS transmitted by the serving gNB 110-1 and / or by other neighboring gNBs 110 and / or ng-eNBs 114. For example, for OTDOA, the directional PRS may be transmitted by gNBs 110 and / or ng-eNBs 114 within the reference cell and / or neighboring cells. If act 515 requests a location estimate from the UE 105, the measurements obtained at act 516 may include some or all of the measurements requested at act 515 or implied at act 515. The UE 105 may measure the directional PRS (e.g., for a reference cell or neighboring cell in the case of OTDOA, or for a serving cell or neighboring cell in the case of ECID) based on the configuration parameters and signal characteristics provided for the directional PRS in the location-related information received at act 511 and / or act 513. For example, the UE 105 may use one or more of the PRS ID, the transmission point ID, the physical cell ID, the code sequence, the muting pattern, the frequency offset (vshift), the period and duration of the positioning occurrence time for the directional PRS to acquire the directional PRS and measure characteristics, such as AOA, TOA, RSTD, RSSI, RSRP, RSRQ, RTT, etc. In some aspects, the UE 105 may also or actually use different (or unique) information for the directional PRS (if received at action 511 and / or at action 513) to acquire and measure the directional PRS. The different (or unique) information may include the identification of the directional PRS, the transmission direction, the horizontal angle range and / or the vertical angle range. For example, as described with respect to Figure 4 As described, in some implementations, the UE 105 may selectively measure directional PRSs that are expected to be LOS and ignore directional PRSs that are expected to be not received or to be NLOS (or multipath). Additionally, or in practice, the UE 105 may use multiple antennas or antenna arrays to selectively receive and measure directional PRSs received for a particular transmit direction and filter out and ignore any signals including directional PRSs received for other transmit directions.

[0072] In some embodiments, at least some of the location measurements obtained at act 516 are provided in an LPP / NPP Provide Location Information message, which is sent from the UE 105 to the AMF 115 in a 5G NAS transport message at act 517. The AMF 115 extracts the LPP / NPP Provide Location Information message from the 5G NAS transport message and relays it to the LMF 120 (e.g., using a 5G LCS AP) at act 518. Using this information, the LMF 120 may then determine the UE 105 location at act 519. The LMF 120 may employ a combination of the LPP / NPP Provide Location Information message and the 5G NAS Transport Message. Figure 3A , 3B 4 and 518 to determine the location of UE 105. For example, when the location measurement results returned by UE 105 at actions 517 and 518 include measurement results for one or more directional PRSs (e.g., measurements of TOA, RSRP, RSRQ, RSTD, RTT), LMF 120 can identify the directional PRS for which the measurement results are provided using a PRS ID or TP ID (e.g., which may be associated with a specific code sequence and / or frequency offset (vshift)) or the time of measurement (e.g., TOA measurement results) and can then use the measurement results for Figures 3A to 4 One or more of the described techniques (eg, ECID, AOA, or OTDOA).

[0073] After the location determination at act 519 , LMF 120 may send the determined location at act 520 to the entity (eg, GMLC 125 or AMF 115 ) that sent the location request at act 501 .

[0074] In some embodiments, UE 105 may determine the location of UE 105 after action 516 ( Figure 5 The location may be determined by UE 105 using a combination of Figures 3A to 4 The position determination by UE 105 may be based on the position-related information received by UE 105 at action 511 and / or at actions 512 and 513, which includes the previously described position-related information and other information (e.g., the positions of the antennas for gNB 110 and / or ng-eNB 114 and any transmission timing differences for gNB 110 and / or ng-eNB 114). UE 105 may then transmit the determined position back to LMF 120 at actions 517 and 518 instead of returning the position measurement result. In this embodiment, action 519 may not occur.

[0075] Figure 6The structure of an example LTE subframe sequence 600 is shown for the case where PRS positioning occurs. The subframe sequence 600 may be suitable for broadcasting PRS and directional PRS from ng-eNB 114 in communication system 100. Figure 6 An example of a subframe sequence for LTE is provided, but similar subframe sequence implementations for other communication technologies / protocols (e.g., 5G and NR) may be implemented. For example, gNB 110 in communication system 100 may broadcast a PRS, directional PRS, or other type of reference signal (RS) or directional RS (e.g., tracking reference signal (TRS)) similar to subframe sequence 600. Figure 6 In FIG. 1 , time is represented horizontally (e.g., on the X-axis), where time increases from left to right, and frequency is represented vertically (e.g., on the Y-axis), where frequency increases (or decreases) from bottom to top. Figure 6 As shown in , downlink and uplink LTE radio frames 610 may each have a 10 millisecond duration. For downlink frequency division duplex (FDD) mode, in the illustrated embodiment, the radio frame 610 is organized into ten subframes 612 of 1 millisecond duration each. Each subframe 612 includes two time slots 614, each of which is 0.5 milliseconds in duration, for example.

[0076] In the frequency domain, the available bandwidth can be divided into evenly spaced subcarriers 616. For example, for a normal length cyclic prefix using, for example, 15 kHz spacing, the subcarriers 616 can be grouped into groups of twelve (12) subcarriers. Each group of 12 subcarriers 616 is referred to as a resource block, and in the above example, the number of subcarriers in a resource block can be written as For a given channel bandwidth, the number of available resource blocks on each channel 622 (also referred to as transmit bandwidth configuration 622) is expressed as For example, for the 3 MHz channel bandwidth in the above example, the number of available resource blocks on each channel 622 is calculated by Given.

[0077] exist Figure 1 In the communication system 100 illustrated in FIG. 1 , ng-eNB 114 or gNB 110 (e.g., either gNB 110-1 or 110-2) may transmit frames or other physical layer signaling sequences to support the use of the same in accordance with the embodiment of the present invention. Figure 6 105 and (as described later) 7, which may be measured and used for UE (e.g., UE 105) position determination. As mentioned, other types of wireless nodes and base stations (e.g., eNBs or WiFi APs) may also be configured to transmit PRS signals (i.e., downlink (DL) PRS) that are similar to or (e.g., in the case of ng-eNB 114) identical to the frame configuration shown in FIG. 7 and (as described later) in FIG. 7, which may be measured and used for UE (e.g., UE 105) position determination. Figure 6 and7 . Since the transmission of PRS by a wireless node or base station involves all UEs within the radio range, the wireless node or base station can also be regarded as transmitting (or broadcasting) PRS. In addition, in some embodiments, such as with respect to Figures 1 to 5 The directional PRS described may have the same Figure 6 and 7 The frame configurations shown and described are similar or identical to the frame configurations.

[0078] The PRS, which has been defined in 3GPP LTE Release 9 and later, may be transmitted by a wireless node (e.g., eNB, ng-eNB 114) after appropriate configuration (e.g., by an operations and maintenance (O&M) server). The PRS may be transmitted in specific positioning subframes grouped into positioning occurrences. For example, in LTE, the PRS positioning occurrence may include a number N of consecutive positioning subframes. PRS , where the number N PRS The PRS positioning occurrence time of the cells supported by the wireless node may be spaced at intervals of milliseconds (or subframes) (represented by the number T). PRS represents) appears periodically, where T PRS can be equal to 5, 10, 20, 40, 80, 160, 320, 640, or 1280 (or any other suitable value). As an example, Figure 6 Indicates the period of positioning occurrence, where N PRS is equal to 4 618 and T PRS Greater than or equal to 20 620. In some embodiments, T PRS It may be measured in terms of the number of subframes between the start of consecutive positioning epochs.

[0079] During each positioning occurrence, the PRS may be transmitted at a constant power. The PRS may also be transmitted at zero power (i.e., muting). Muting (which disconnects regularly scheduled PRS transmissions) may be applicable when PRS signals between different cells overlap by occurring at the same or nearly the same time. In this case, the PRS signals from some cells may be muted while the PRS signals from other cells are transmitted (e.g., at a constant power). Muting may assist in signal acquisition and in determining the location of the PRS by a UE (e.g., Figure 1 and 5 The UE 105 and Figure 4The TOA and RSTD measurements of PRS signals (which are not muted (by avoiding interference from muted PRS signals)) made by the UE 420 in the UE 420 are shown in Figure 4. Muting can be considered as the non-transmission of PRS at a given positioning occurrence for a particular cell. The muting pattern (also called muting sequence) can be signaled to the UE using a bit string (e.g., using LPP or NPP). For example, in the bit string signaled to indicate the muting pattern, if the bit at positioning j is set to "0", then the UE can infer that the PRS is muted at the jth positioning occurrence.

[0080] To further improve the audibility of the PRS, the positioning subframe may be a low-interference subframe transmitted without using the user data channel. As a result, in an ideal synchronized network, the PRS may receive interference from other cell PRSs with the same PRS pattern index (i.e., with the same frequency offset) but not from data transmissions. In LTE, the frequency offset is defined, for example, as a function of the PRS ID of the cell or TP (expressed as ) or defined as a function of the physical cell identifier (PCI) when no PRS ID is assigned (expressed as ), which results in an effective frequency reuse factor of 6.

[0081] To further improve the audibility of the PRS (e.g., when the PRS bandwidth is limited, e.g., with only 6 resource blocks corresponding to a 1.4 MHz bandwidth), the frequency band used for consecutive PRS positioning occurrences (or consecutive PRS subframes) may be changed in a known and predictable manner via frequency hopping. In addition, a cell supported by a wireless node may support more than one PRS configuration, wherein each PRS configuration may include a different frequency offset (vshift), a different carrier frequency, a different bandwidth, a different code sequence, and / or a subframe number (N) specific to each positioning occurrence. PRS ) and specific period (T PRS ) of the PRS positioning occurrence time. In a certain implementation, one or more of the PRS configurations supported in the cell may be for directional PRS and may then have additional different characteristics, such as different transmission directions, different horizontal angle ranges, and / or different vertical angle ranges. Other enhancements to PRS may also be supported by the wireless node.

[0082] As discussed herein (e.g., with respect to actions 511, 512, and 513 of signaling flow 500), in some embodiments, OTDOA assistance data may be provided by a location server (e.g., Figure 1 The assistance data may be provided to the UE 105 by the LMF 120, E-SMLC, etc. of the UE 105. For example, the assistance data may provide the center channel frequency of each cell, various PRS configuration parameters (e.g., NPRS , T PRS , muting sequence, frequency transition sequence, PRS ID, PRS bandwidth), cell shared ID, PRS signal characteristics associated with directional PRS, and / or other cell-related parameters applicable to OTDOA or some other positioning method (e.g., ECID).

[0083] PRS-based positioning by UE 105 may be facilitated by indicating a serving cell for UE 105 in the OTDOA assistance data (e.g., where the reference cell is indicated as the serving cell). In the case of a UE 105 with 5G radio access, the reference cell may be selected by LMF 120 as a cell (e.g., supported by gNB 110) with good coverage at the expected estimated location of UE 105 (e.g., as indicated by a known 5G serving cell for UE 105).

[0084] In some embodiments, the OTDOA assistance data may also include an "expected RSTD" parameter and an uncertainty in the expected RSTD parameter, which provides information to the UE 105 about the RSTD value that the UE 105 is expected to measure between the reference cell and each neighboring cell at its current location. The expected RSTD and the associated uncertainty may define a search window for the UE 105 within which the UE 105 is expected to measure RSTD values. The OTDOA assistance information may also include a PRS configuration information parameter that allows the UE 105 to determine when the PRS positioning epoch occurs relative to the PRS positioning epoch of the reference cell on signals received from various neighboring cells, and to determine the PRS sequences transmitted from the various cells in order to measure signal arrival time (TOA) or RSTD.

[0085] Using the RSTD measurements, the known absolute or relative transmit timing for each cell, and the known locations of the physical transmit antennas of the wireless nodes of the reference and neighboring cells, the location of UE 105 may be calculated (e.g., by UE 105, by LMF 120, or by some other node such as gNB 110 or ng-eNB 114). More specifically, the RSTD of neighbor cell "k" relative to reference cell "Ref" may be given as (TOA k -TOA Ref), where the TOA value may be measured modulo one subframe duration (1 millisecond) to remove the effect of measuring different subframes at different times. The TOA measurements of different cells may then be converted into RSTD measurements (e.g., as defined in 3GPP TS 36.214 entitled "Physical layer; Measurements") and sent to a location server (e.g., LMF 120 or E-SMLC) by UE 105. Using (i) RSTD measurements, (ii) known absolute or relative transmit timing for each cell, (iii) known locations of physical transmit antennas of the reference cell and neighboring cells, and / or (iv) directional PRS characteristics such as transmit direction, the location of UE 105 may be determined.

[0086] Figure 7 Other aspects of PRS transmission for a cell supported by a wireless node (e.g., ng-eNB 114 or gNB 110) are described. Figure 7 It is assumed that PRS transmission is used for LTE, but the PRS transmission is different from Figure 7 Display and targeting Figure 7 Aspects the same or similar to those described may apply to 5G, NR and / or other wireless technologies. Figure 7 Shows how the PRS positioning occurs at the time of the system frame number (SFN), cell-specific subframe offset (Δ PRS ) and PRS period (T PRS )720. Typically, the cell-specific PRS subframe configuration is determined by a “PRS configuration index” contained in the OTDOA assistance data. PRS Definition. PRS period (T PRS )720 and cell-specific subframe deviation (Δ PRS ) is based on PRS configuration index I PRS It is defined in 3GPP TS 36.211 entitled “Physical channels and modulation” as illustrated in Table 1 below.

[0087]

[0088] Table 1

[0089] The PRS configuration is defined with reference to the system frame number (SFN) of the cell transmitting the PRS. PRS In the first subframe of a downlink subframe, the PRS instance may satisfy:

[0090]

[0091] where nf is SFN, where 0≤n f ≤1023, n s Because f The timeslot number within a defined radio frame, where 0 ≤ n s ≤19, T PRS is the PRS period, and Δ PRS is the cell-specific subframe offset.

[0092] like Figure 7 As shown in PRS 752 may be defined by the number of subframes transmitted starting from system frame number 0 (time slot "number 0", denoted as time slot 750) to the start of the first (subsequent) PRS positioning occurrence. Figure 7 In the example, the number of consecutive positioning subframes 718 (N PRS ) is equal to 4.

[0093] In some embodiments, when UE 105 receives the PRS configuration index I in the OTDOA assistance data for a particular cell, PRS When UE 105 can use Table 1 to determine the PRS period T PRS and PRS subframe deviation Δ PRS UE 105 may then determine the radio frame, subframe, and time slot when the PRS is scheduled in the cell (e.g., using equation (1)). OTDOA assistance data may be determined, for example, by LMF 120 or E-SMLC and include assistance data for a reference cell and numbers of neighboring cells supported by various wireless nodes.

[0094] Typically, the PRS occurrence times from all cells in the network using the same frequency are aligned in time and may have a fixed known time offset relative to other cells in the network using different frequencies. In a SFN synchronous network, all wireless nodes (e.g., gNB, ng-eNB, eNB, etc.) may be aligned on both frame boundaries and system frame numbers. Thus, in a SFN synchronous network, all cells supported by various wireless nodes may use the same PRS configuration index for any particular frequency for PRS transmission. On the other hand, in a SFN asynchronous network, various wireless nodes may be aligned on frame boundaries but not on system frame numbers. Thus, in a SFN asynchronous network, the PRS configuration index for each cell may be independently configured by the network so that the PRS occurrence times are aligned in time.

[0095] If UE 105 can obtain the cell timing (e.g., SFN or frame number) of at least one of the cells (e.g., reference cell or serving cell) (e.g., it can be performed as Figure 5516 in the example above), UE 105 may determine the timing of the PRS occurrence times of the reference and neighboring cells (e.g., in an LTE network or a 5G network (e.g., a network in communication system 100) for OTDOA positioning. The timing of other cells may then be derived by UE 105 based on the assumption that, for example, the PRS occurrence times from different cells overlap.

[0096] As defined by 3GPP (e.g., in 3GPP TS 36.211), for LTE systems, the sequence of subframes used to transmit PRS (e.g., for OTDOA positioning) may be characterized and defined by several parameters as previously described, including: (i) a reserved block of bandwidth (BW); (ii) a configuration index I; PRS (iii) Duration N PRS ; (iv) optional silent mode; and (v) silent sequence period T REP , which may be implicitly included as part of the silent mode in (iv) (when present). In some cases, at very low PRS duty cycles, N PRS =1,T PRS = 160 subframes (equivalent to 160 milliseconds) and BW = 1.4 MHz, 3 MHz, 5 MHz, 10 MHz, 15 MHz or 20 MHz. To increase the PRS duty cycle, N PRS The value increases to six (i.e., N PRS =6) and the bandwidth (BW) value can be increased to the system bandwidth (ie, in the case of LTE, BW = LTE system bandwidth). PRS (e.g., greater than six) and / or shorter T PRS (e.g., less than 160 milliseconds) to more than the full duty cycle (i.e., N PRS =T PRS ) can also be used in later versions of LPP according to 3GPP TS 36.355. Directional PRS (e.g., as combined with Figures 1 to 5 ) may be configured as just described according to 3GPP TS, and may, for example, use a low PRS duty cycle (e.g., N PRS =1,T PRS =160 subframes) or high duty cycle.

[0097] Figure 8 A flow chart is shown of an example process 800 performed at a first base station configured to transmit signaling (e.g., according to an LTE, NR, or 5G protocol) to support and facilitate positioning of a mobile device (e.g., UE 105 or UE 420). Process 800 may be performed by a base station (e.g., Figure 4 Base station 410, Figure 2The base station 202 in the example, eNB for LTE, gNB for 5G or NR (e.g. Figure 1 gNB 110 in , or ng-eNB for 5G (e.g. Figure 1 Procedure 800 may also be supported by a positioning-only beacon that transmits signals (e.g., NR or LTE signals) but does not receive signals.

[0098] Process 800 includes generating (by a first base station) a plurality of directional positioning reference signals (PRS) for at least one cell of the first base station at block 810, wherein each of the plurality of directional PRSs comprises at least one signal characteristic and a transmission direction. The at least one cell may be a serving cell of the mobile device. In an embodiment, at least one of the at least one signal characteristic and the transmission direction may be unique (e.g., may be different from the corresponding at least one signal characteristic and / or the corresponding transmission direction of any other directional PRS transmitted by the first base station or by other neighboring base stations for at least one cell, respectively).

[0099] The process 800 further includes transmitting each of the plurality of directional PRSs within the at least one cell at block 820, wherein each of the plurality of directional PRSs is transmitted in the transmit direction. The at least one signal characteristic of any one of the plurality of directional PRSs may indicate a transmit direction for that directional PRS. For example, the at least one signal characteristic may identify a directional PRS and, due to being different from the corresponding at least one signal characteristic for any other directional PRS in the plurality of directional PRSs, may thereby indicate a known transmit direction for this directional PRS. Thus, the at least one signal characteristic may be used to reduce or remove, for example, multipath interference, or otherwise facilitate, for example, Figures 3A to 4 The position of the mobile device is determined as described in.

[0100] At least one signal characteristic may include, for example, frequency (e.g., carrier frequency), frequency offset, code sequence, muting pattern, transmission time or a set of transmission times, or some combination thereof. In some embodiments, transmitting the plurality of directional PRSs at block 820 may include directing the plurality of directional PRSs via a controllable antenna array (of a base station) configured to beamform each directional PRS in a respective transmission direction. In some embodiments, the transmission direction (for a particular directional PRS) may include a first angle from a continuous horizontal angle range and / or a second angle from a continuous vertical angle range. In some embodiments, the transmission direction of a particular directional PRS may include a continuous horizontal angle range, a continuous vertical angle range, or a combination thereof. In some embodiments, the transmission direction for a particular directional PRS may be selected from a set of discrete transmission directions (e.g., represented as one angle or multiple angles). The directional PRSs may be transmitted in substantially non-overlapping directions, each of which is associated with at least one signal characteristic, the at least one signal characteristic allowing identification of each directional PRS (and thus determination of the transmission direction of each directional PRS).

[0101] In some embodiments, at least one of the multiple directional PRSs transmitted at block 820 may be detected by a mobile device to facilitate position determination of the mobile device at a device with positioning capabilities based on an observed time difference of arrival (OTDOA) positioning method, an angle of departure (AOD) positioning method, and / or an enhanced cell ID (ECID) positioning method. Other positioning methods that utilize the transmission of directional PRS signals may also be used. As mentioned, the position determination operation at the device with positioning capabilities may be performed at one or more of, for example, a first base station (transmitting the directional PRS), a second base station different from the first base station, a mobile device, a location server (e.g., LMF 120, SLP, or E-SMLC), and / or other types of devices. In these embodiments, for example, as in actions 509 and 510 in the signaling process 500 when LMF 120 is a device with positioning capabilities, or as in action 511 when UE 105 is a device with positioning capabilities, the first base station may send a transmission direction for at least one of the multiple directional PRSs and / or other configuration parameters and signal characteristics of at least one of the multiple directional PRSs to the device with positioning capabilities.

[0102] In embodiments where at least one of the plurality of directional PRSs transmitted at block 820 is detectable by a mobile device to facilitate position determination of the mobile device at a device with positioning capabilities, the at least one of the plurality of directional PRSs may be detectable by the mobile device based on a transmit direction for the at least one of the plurality of directional PRSs, at least one signal characteristic of the at least one of the plurality of directional PRSs, or a combination thereof. For example, the at least one signal characteristic for the at least one of the plurality of directional PRSs may be used by the mobile device to acquire and measure the at least one of the plurality of directional PRSs. For example, the mobile device may integrate the directional PRS signal using coherent or non-coherent integration over a period of time (e.g., the duration of one positioning epoch), and may compare or correlate the integrated signal with an expected signal having the same at least one first signal characteristic, which may enable the mobile device to detect and measure the directional PRS. In some of these embodiments, the at least one signal characteristic may include a single signal characteristic that is different from a corresponding single signal characteristic of other PRSs and / or other directional PRS signals that may be received by the mobile device. Alternatively, in some of these embodiments, the at least one signal characteristic may include a combination of two or more signal characteristics that are collectively different from corresponding combinations of two or more signal characteristics of other PRS and / or other directional PRS signals that may be received by the mobile device. In some of these embodiments, the mobile device may use the transmit direction of the at least one of the plurality of directional PRSs detectable by the mobile device to detect such directional PRS by using multiple antennas or antenna arrays, such as in combination with Figure 4 The description selectively receives a signal transmitted only in the transmission direction of this directional PRS.

[0103] In some embodiments, the process 800 may further include sending at least one of the transmission direction or at least one signal characteristic of the at least one of the plurality of directional PRSs to the mobile device. The sending may be based on a broadcast within the at least one cell or based on a point-to-point transfer, such as described for action 511 in the signaling process 500 in the case of a broadcast.

[0104] In embodiments where at least one of the plurality of directional PRSs transmitted at block 820 is detectable by a mobile device to facilitate position determination of the mobile device at a positioning-capable device, the position determination operation at the positioning-capable device may include determining the presence or absence of a multipath for at least one of the plurality of directional PRSs based on an associated transmission direction of the at least one of the plurality of directional PRSs and an estimated position of the mobile device. In this context, determining the position of the mobile device at the positioning-capable device may be based at least in part on the determined presence or absence of a multipath. For example, and as for Figure 4As described, when determining the presence of multipath, determining the location of the mobile device may include not considering (eg, ignoring) at least one of the plurality of directional PRSs transmitted at block 820. Figure 4 As described, when it is determined that multipath does not exist, determining the position of the mobile device may include using at least one of the multiple directional PRSs transmitted at block 820 (e.g., using measurements of at least one of the multiple directional PRSs obtained by the mobile device). The estimated position of the mobile device may be based at least in part on a serving cell of the mobile device or on a previous determination of the position of the mobile device. For example, the previous determination may be based at least in part on at least one of the multiple directional PRSs transmitted at block 820 and detectable by the mobile device (e.g., based on measurements of at least one of the multiple directional PRSs obtained by the mobile device).

[0105] Fig. 9 Displays are usually displayed on mobile devices (such as Figure 1 and 5 UE 105 or Figure 4 Flowchart of an example process 900 for supporting positioning of a mobile device performed at a UE (e.g., a UE of UE 420 in FIG. 1 ). The process 900 includes receiving, at block 910, at a mobile device, a first directional positioning reference signal (PRS) transmitted by a first base station (e.g., gNB 110, ng-eNB 114, or eNB) within at least one cell of the first base station, wherein the first directional PRS includes at least one first signal characteristic and a first transmission direction. The at least one cell may be a serving cell for the mobile device, e.g., a cell at the first base station serving the mobile device. Figure 1 1 and the mobile device is UE 105. As mentioned, at least one first signal characteristic may include, for example, one or more of a carrier frequency, a frequency offset (e.g., vshift), a code sequence (e.g., a PRS code sequence), a muting pattern, a bandwidth, and / or a transmission time (or a set of transmission times). In some embodiments, the first directional PRS is transmitted from the first base station via a controllable antenna array configured to beamform the first directional PRS in the first transmission direction. As also mentioned, the first transmission direction may include (or be defined by) a direction having a continuous horizontal angle range and / or a continuous vertical angle range.

[0106] Continue to view Fig. 9, the process 900 further includes obtaining at least one first measurement result of the first directional PRS based at least in part on the at least one first signal characteristic at block 920. Block 920 may correspond to action 516 or a portion of action 516 in the signaling flow 500. The at least one first measurement result of the first directional PRS obtained at block 920 may include, for example, time of arrival (TOA), reference signal time difference (RSTD), received signal strength indication (RSSI), reference signal received power (RSRP), reference signal received quality (RSRQ), angle of arrival (AOA), signal propagation time, round trip signal propagation time (RTT), detection of at least one first signal characteristic, and / or any combination thereof. At block 920, the at least one first signal characteristic of the first directional PRS may be used by the mobile device to acquire and measure the first directional PRS signal. For example, the mobile device may integrate the first directional PRS and other received signals using coherent or incoherent integration over a period of time (e.g., the duration of one PRS fix epoch), and may compare or correlate the integrated signal with an expected signal having the same at least one first signal characteristic, which may enable the mobile device to detect and measure the first directional PRS. In some embodiments, the at least one first signal characteristic may include a single signal characteristic that is different from a corresponding single signal characteristic of other PRS and / or other directional PRS signals that may also be received by the mobile device. In other embodiments, the at least one first signal characteristic may include a combination of two or more signal characteristics that are collectively different from corresponding combinations of two or more signal characteristics of other PRS and / or other directional PRS signals that may be received by the mobile device. In some embodiments, the mobile device may use the first transmit direction of the first directional PRS to acquire and measure the first directional PRS at block 920 by using multiple antennas or antenna arrays to, for example, combine Figure 4 In some embodiments, at least one first signal characteristic of the first directional PRS may be received by the mobile device (e.g., before executing block 920) from a first base station (e.g., as described for action 511 of the signaling process 500) or from a location server such as an E-SMLC, SLP, or LMF 120 (e.g., as described for actions 512 and 513 of the signaling process 500).

[0107] Process 900 further includes facilitating, at a location-capable device, location determination of a mobile device based at least in part on the at least one first measurement result, at block 930. The location determination for block 930 may correspond to act 519 in signaling flow 500. As discussed herein, a location-capable device (in which at least some of the location determination operations may be performed) may include, for example, a mobile device, a first base station, some other base station, and / or a location server (e.g., Figure 1 The location determination of the mobile device at the device with positioning capability can be based on, for example, an observed time difference of arrival (OTDOA) positioning method, an angle of departure (AOD) positioning method, an enhanced cell ID (ECID) positioning method, or a combination of these methods, and can be adopted in combination with the present invention. Figure 3A , 3B When the positioning-capable device corresponds to a first base station or location server (e.g., E-SMLC, SLP, or LMF 120), facilitating determining the location in block 930 may include sending at least one first measurement result of a first directional PRS to the positioning-capable device, such as at actions 517 and 518 in the signaling flow 500 when the positioning-capable device is LMF 120.

[0108] In some embodiments, determining a position of a mobile device at a positioning-capable device may include determining the presence or absence of a multipath of the first directional PRS based on a first transmit direction of the first directional PRS and an estimated position of the mobile device. In this context, determining the position of the mobile device may be based at least in part on the determined presence or absence of a multipath. For example, and as for Figure 4 As described, when determining the presence of multipath, determining the location of the mobile device may include not considering (eg, ignoring) at least one first measurement result obtained at block 920. Figure 4 As described, when it is determined that multipath does not exist, determining the position of the mobile device may include using in the position determination at least one first measurement result obtained at block 920. The estimated position of the mobile device may be based at least in part on a serving cell of the mobile device or on a previous determination of the position of the mobile device based at least in part on the at least one first measurement result.

[0109] In some embodiments, location determination of a mobile device may be implemented by the mobile device based on measurements of a plurality of directional PRS signals. Thus, in such embodiments, procedure 900 may further include receiving at the mobile device a second directional PRS transmitted by a second base station within at least one cell for the second base station, wherein the second directional PRS includes at least one second signal characteristic and a second transmission direction, and wherein the at least one second signal characteristic and the second transmission direction of the second directional PRS are different from at least one first signal characteristic and the first transmission direction of the first directional PRS, respectively. In such embodiments, procedure 900 may also include obtaining at least one second measurement of the second directional PRS based at least in part on the at least one second signal characteristic of the second directional PRS, and facilitating location determination of the mobile device based at least in part on the at least one first measurement and the at least one second measurement at a device with positioning capabilities.

[0110] In some embodiments of process 900, at least one of the at least one first signal characteristic and the first transmission direction may be unique (e.g., may be different from the corresponding signal characteristic and / or the corresponding transmission direction of any other directional PRS transmitted by the first base station or by some other neighboring base station within at least one cell, respectively).

[0111] Fig.10 The display is generally performed at a device with positioning capability to support mobile devices (such as Figure 1 and 5 UE105 or Figure 4 4. The present invention is a flow chart of an example procedure 1000 for determining the location of a UE 420). Procedure 1000 may be performed by a mobile device, by a base station (e.g., an eNB, ng-eNB 114, or gNB 110), or by a location server (e.g., an E-SMLC, an SLP, or an LMF 120).

[0112] Procedure 1000 includes obtaining, at block 1010, from a mobile device at least one first measurement result of a first directional positioning reference signal (PRS) transmitted by a first base station in at least one cell of the first base station, wherein the first directional PRS includes at least one first signal characteristic and a first transmission direction. For example, in the case where the first base station corresponds to gNB 110-1 and the mobile device corresponds to UE 105, the at least one cell may be a serving cell for the mobile device. If the positioning-capable device is a mobile device, then the at least one first measurement result may be obtained directly at block 1010, or if the positioning-capable device is a base station (e.g., the first base station) or a location server (e.g., LMF 120), then the at least one first measurement result may be obtained at block 1010 by receiving from the mobile device at the positioning-capable device. For example, if the device with positioning capability is a base station, then at least one first measurement result may be received from the mobile device in a radio resource control (RRC) message, or if the device with positioning capability is a location server, then at least one first measurement result may be received from the mobile device in an LPP, NPP or NRPP message (for example, as described in actions 517 and 518 of the signaling process 500 for the location server corresponding to LMF 120).

[0113] Process 1000 further includes determining a location of the mobile device based at least in part on the at least one first measurement result and the first transmission direction at block 1020. In some embodiments where the device with positioning capability is a location server (e.g., LMF 120), block 1020 may correspond to action 519 in signaling flow 500.

[0114] As discussed herein, at least one first signal characteristic may include a carrier frequency, a frequency offset (e.g., vshift), a code sequence (e.g., a PRS code sequence), a muting pattern, a bandwidth, a transmission time (or a set of transmission times), or some combination thereof. The transmission direction may include a continuous horizontal angle range and / or a continuous vertical angle range. In some embodiments, the first directional PRS may be transmitted from the first base station via a controllable antenna array configured to beamform the first directional PRS in the first transmission direction. At least one first measurement result of the first directional PRS may include a time of arrival (TOA), a reference signal time difference (RSTD), a received signal strength indication (RSSI), a reference signal received power (RSRP), a reference signal received quality (RSRQ), an angle of arrival (AOA), a signal propagation time, a round trip signal propagation time (RTT), a detection of at least one first signal characteristic, and / or some combination thereof.

[0115] In some embodiments, the positioning-capable device may include a mobile device, and in such embodiments, the process 1000 may further include receiving at least one first signal characteristic and / or a first transmission direction from a first base station or from a location server, such as an E-SMLC, an SLP, or an LMF, such as LMF 120. The at least one first signal characteristic and / or the first transmission direction may be received from the first base station by receiving a broadcast signal from the first base station, such as described for action 511 in the signaling process 500. The at least one first signal characteristic and / or the first transmission direction may be received from the location server, such as LMF 120, by receiving an LPP or NPP message from the location server, such as described for actions 512 and 513 in the signaling process 500.

[0116] In some embodiments, the positioning-capable device may include a first base station or a location server (e.g., E-SMLC, SLP, or LMF 120), and in such embodiments, the process 1000 may further include sending at least one first signal characteristic and / or a first transmission direction to the mobile device. For example, when the positioning-capable device includes a first base station, the at least one first signal characteristic and / or the first transmission direction may be sent to the mobile station using a broadcast, such as described for action 511 in the signaling process 500. For example, when the positioning-capable device includes a location server (e.g., LMF 120), the at least one first signal characteristic and / or the first transmission direction may be sent to the mobile device in an LPP or NPP message, such as described for actions 512 and 513 in the signaling process 500.

[0117] In some embodiments, and as previously described herein, at least one first signal characteristic and / or first transmission direction may enable or assist the mobile device to acquire and measure the first directional PRS and obtain at least one first measurement result of the first directional PRS (e.g., at block 1010 if the mobile device is a positioning-capable device, or before block 1010 if the positioning-capable device includes a first base station or location server). For example, the mobile device may integrate the first directional PRS and other received signals using coherent or incoherent integration over a period of time (e.g., the duration of one PRS fix epoch), and may compare or correlate the integrated signal with an expected signal having the same at least one first signal characteristic, which may enable the mobile device to detect and measure the first directional PRS.

[0118] In some embodiments, determining the location of the mobile device at block 1020 may be based on an observed time difference of arrival (OTDOA) positioning method, an angle of departure (AOD) positioning method, or an enhanced cell ID (ECID) positioning method, or some combination thereof. In such embodiments, process 1000 may also include determining the presence or absence of a multipath for the first directional PRS based on the first transmit direction and the estimated location of the mobile device, wherein determining the location of the mobile device is based at least in part on the determined presence or absence of a multipath. For example, and as for Figure 4 As described, when determining the presence of multipath, determining the location of the mobile device at block 1020 may include not considering (eg, ignoring) at least one first measurement result obtained at block 1010. Figure 4 As described, when the absence of multipath is determined, determining the position of the mobile device at block 1020 may include using at least one first measurement result obtained at block 1010 in the position determination at block 1020. The estimated position of the mobile device may be based at least in part on a serving cell of the mobile device or on a previous determination of the position of the mobile device based at least in part on the at least one first measurement result obtained at block 1010.

[0119] In some embodiments, the location determination of the mobile device at block 1020 may be implemented by the mobile device based on measurement results of multiple directional PRS signals. Therefore, in such embodiments, the procedure 1000 may further include obtaining from the mobile device at least one second measurement result of a second directional PRS transmitted by a second base station in at least one cell of the second base station, wherein the second directional PRS includes at least one second signal characteristic and a second transmission direction, and wherein the at least one second signal characteristic and the second transmission direction of the second directional PRS are different from the at least one first signal characteristic and the first transmission direction of the first directional PRS, respectively. In such embodiments, the procedure 1000 may also include determining the location of the mobile device based at least in part on the at least one first measurement result, the at least one second measurement result, the first transmission direction of the first directional PRS, and the second transmission direction of the second directional PRS.

[0120] In some embodiments of process 1000, at least one of the at least one first signal characteristic of the first directional PRS and the first transmission direction may be unique (e.g., may be different from the corresponding signal characteristic and / or the corresponding transmission direction of any other directional PRS transmitted by the first base station or by some other neighboring base station within at least one cell, respectively).

[0121] Fig.11A schematic diagram showing an example wireless node 1100 (eg, a base station, access point, or server) that may be similar to, for example, Figure 1 , 2 , 4 and 5 (e.g., components of gNBs 110-1 and 110-2, ng-eNB 114, base station 202, base station 410, LMF 120, 5GC 140) or any of the various nodes discussed otherwise herein (e.g., E-SMLC or SLP), and configured to have functionality similar to that of any of the various nodes. Wireless node 1100 may include one or more communication modules 1110a to 1110n, which may be electrically coupled to one or more antennas 1116a to 1116n for communicating with wireless devices (e.g., Figure 1 and 5 105). Each of the communication modules 1110a to 1110n may include a respective transmitter 1112a to 1112n for sending signals (e.g., downlink messages, which may be arranged in frames and may include directional positioning reference signals such as those described herein), and optionally, a respective receiver 1114a to 1114n (e.g., for a node configured to receive and process uplink communications). In embodiments in which an implemented node includes both a transmitter and a receiver, a communication module including a transmitter and a receiver may be referred to as a transceiver. Node 1100 may also include a network interface 1120 for communicating with other network nodes via wired means (e.g., by sending and receiving queries and responses). For example, node 1100 may be configured to communicate with a gateway or other suitable device of a network (e.g., via wired or wireless backhaul communications) to facilitate communication with one or more core network nodes (e.g., Figure 1 and 5 Additionally and / or alternatively, communication modules 1110a to 1110n and / or respective antennas 1116a to 1116n may also be used to perform communications with other network nodes.

[0122] The node 1100 may also include other components that may be used with the embodiments described herein. For example, in some embodiments, the node 1100 may include a processor (also referred to as a controller) 1130 to manage communications with other nodes (e.g., sending and receiving messages), generate communication signals (including generating directional PRS signals), and provide other related functionality, including functionality for implementing the various processes and methods described herein. Thus, for example, in combination with other modules / units of the node 1100, the processor may be configured to cause the node 1100 to generate a plurality of directional positioning reference signals (PRS) for at least one cell of the base station when acting as a base station (e.g., gNB 110 or ng-eNB 114), wherein each of the plurality of directional PRSs includes at least one signal characteristic and a transmission direction, and each of the plurality of directional PRSs is transmitted within the at least one cell, wherein each of the plurality of directional PRSs is transmitted in the transmission direction. Similarly, for example, in combination with other modules / units of node 1100, the processor may be configured to cause node 1110, when acting as a device with positioning capabilities, to obtain, from a mobile device, at least one first measurement result of a first directional positioning reference signal (PRS) transmitted by a base station in at least one cell for the base station (wherein the first directional PRS includes at least one first signal characteristic and a first transmission direction), and to determine the position of the mobile device based at least in part on the at least one first measurement result and the first transmission direction.

[0123] The processor 1130 may be coupled to (or otherwise in communication with) a memory 1140, which may include one or more modules (implemented in hardware in software) to facilitate controlling the operation of the node 1100. For example, the memory 1140 may include an application module 1146 having computer program code required for various applications to perform the operation of the node 1100. For example, the processor 1130 may be configured (e.g., using program code provided via the application module 1146 or some other module in the memory 1140) to control the operation of the antennas 1116a-1116n so as to adjustably control antenna transmit power and phase, gain mode, antenna direction (e.g., the direction in which the resulting radiated beam propagates from the antennas 1116a-1116n), antenna diversity, and other adjustable antenna parameters of the antennas 1116a-1116n of the node 1100. Control of the antennas 1116a to 1116n of the node 1100 (which together constitute the antenna array of the node 1100) may allow, for example, directional PRS signals to be beamformed and transmitted in a particular direction characterized in part by a directional angle and a beam width. In some embodiments, the configuration of the antennas may be controlled according to pre-stored configuration data provided when the node 1100 is manufactured or deployed, or according to data obtained from a remote device (e.g., a central server that sends data representing the antenna configuration and other operating parameters to be used for the node 1100). In some implementations, the wireless node 1100 may also be configured to perform location data services or perform other types of services for multiple wireless devices (clients) communicating with the wireless node 1100 (or communicating with a server coupled to the wireless node 1100), and provide location data and / or assistance data to such multiple wireless devices.

[0124] In addition, in some embodiments, the memory 1140 may also include a neighbor cell relationship controller (e.g., a neighbor cell discovery module) 1142 to manage neighbor cell relations (e.g., maintain a neighbor cell list 1144) and provide other related functionality. In some embodiments, the node 1110 may also include one or more sensors (not shown) and other devices (e.g., cameras).

[0125] Fig.12 1200 that can utilize the various procedures and techniques described herein. In terms of implementation and / or functionality, UE 1200 can be similar to other UEs described herein (including Figure 1 and 5 The UE 105 and Figure 4 In addition, Fig.12The implementations described in the specification may also be used to at least partially implement some of the nodes and devices described throughout the present invention, including such nodes and devices as base stations (e.g., gNB 110, ng-eNB 114, eNB, etc.), location servers (e.g., LMF 120), and Figures 1 to 10 Described in and for Figures 1 to 10 Other components and devices described.

[0126] UE 1200 includes a processor 1211 (or processor core) and a memory 1240. As described herein, UE 1200 is configured to detect and process directional positioning reference signals (PRS) used to facilitate position determination operations. UE 1200 may optionally include a trusted environment operably connected to memory 1240 via a public bus 1201 or a private bus (not shown). UE 1200 may also include a communication interface 1220 and a processor configured to communicate with the user via a wireless network (e.g., a wireless antenna 1222). Figure 1 The UE 1200 may include a wireless transceiver 1221 that sends and receives wireless signals 1223 (which may include LTE or NR frames including directional PRS signals) to and from the NG-RAN 135 and 5GC 140 of the UE 1200. The wireless transceiver 1221 is connected to the bus 1201 via a communication interface 1220. In this document, the UE 1200 is illustrated as having a single wireless transceiver 1221. However, the UE 1200 may alternatively have multiple wireless transceivers 1221 and / or multiple wireless antennas 1222 to support multiple communication standards, such as WiFi, CDMA, Wideband CDMA (WCDMA), Long Term Evolution (LTE), 5G, NR, Short-range wireless communication technology, etc.

[0127] The communication interface 1220 and / or the wireless transceiver 1221 may support operation on multiple carriers (waveform signals of different frequencies). A multi-carrier transmitter may transmit modulated signals simultaneously on the multiple carriers. Each modulated signal may be a code division multiple access (CDMA) signal, a time division multiple access (TDMA) signal, an orthogonal frequency division multiple access (OFDMA) signal, a single carrier frequency division multiple access (SC-FDMA) signal, etc. Each modulated signal may be sent on a different carrier and may carry pilots, control information, overhead information, data, etc.

[0128] UE 1200 may also include a user interface 1250 (e.g., a display, keyboard, touch screen, graphical user interface (GUI)), and a satellite positioning system (SPS) receiver 1255 that receives SPS signals 1259 (e.g., from SPS satellites) via an SPS antenna 1258 (which may be the same antenna as wireless antenna 1222 or may be different). SPS receiver 1255 may communicate with a single global navigation satellite system (GNSS) or multiple such systems. GNSS may include, but is not limited to, a global positioning system (GPS), Galileo, Glonass, Beidou (Compass), etc. SPS satellites are also referred to as satellites, space vehicles (SV), etc. SPS receiver 1255 measures SPS signals 1259, and may use the measurements of SPS signals 1259 to determine the location of UE 1200. The processor 1211, the memory 1240, the digital signal processor (DSP) 1212 and / or a dedicated processor (not shown) may also be used to process the SPS signal 1259 in whole or in part, and / or in conjunction with the SPS receiver 1255 to calculate (approximately or more accurately) the position of the UE 1200. Alternatively, the UE 1200 may forward the SPS measurement results to a location server (e.g., E-SMLC, LMF (e.g., Figure 1 The storage of information from the SPS signal 1259 or other position signals is performed using a memory 1240 or registers (not shown). Although only one processor 1211, one DSP 1212, and one memory 1240 are shown in FIG. Fig.12 In the embodiment of the present invention, any, a pair or all of these components may be used by the UE 1200, but more than one, a pair or all of these components may be used by the UE 1200. The processor 1211 and the DSP 1212 associated with the UE 1200 are connected to the bus 1201.

[0129] The memory 1240 may include a non-transitory computer-readable storage medium (or media) that stores functions as one or more instructions or program codes. The media that may constitute the memory 1240 include (but are not limited to) RAM, ROM, FLASH, optical disk drives, etc. In general, the functions stored by the memory 1240 are executed by a general-purpose processor such as the processor 1211, a dedicated processor such as the DSP 1212, etc. Therefore, the memory 1240 is a processor-readable memory and / or a computer-readable memory that stores software (program code, instructions, etc.) configured to cause the processor 1211 and / or the DSP 1212 to perform the described functions. Alternatively, one or more functions of the UE 1200 may be performed in whole or in part in hardware.

[0130] UE 1200 may use various techniques to estimate its current position within the associated system based on other communicating entities in view and / or information available to UE 1200. For example, UE 1200 may use information from a base station (e.g., gNB, ng-eNB), an access point (AP) associated with one or more wireless local area networks (WLANs), a short-range wireless communication technology (e.g., Wireless technology or The UE 1200 may estimate its position based on information obtained from a personal area network (PAN) of a wireless communication network (WLAN), a global navigation satellite system (GNSS), or other satellite positioning system (SPS) satellite, and / or map data obtained from a map server or other server (e.g., an LMF, an E-SMLC, or an SLP). In some cases, a location server, which may be an E-SMLC, an SLP, a standalone serving mobile location center (SAS), or an LMF, may provide assistance data to the UE 1200 to allow or assist the UE 1200 to acquire signals (e.g., signals from a WLAN AP, signals from a cellular base station (including directional PRS signals), signals from GNSS satellites, etc.) and use these signals to make position-related measurements. UE 1200 may then provide the measurement results to a location server to compute a position estimate based on the measurement results and possibly also based on other assistance data provided by the location server (e.g., orbit and timing data for GNSS satellites, configuration parameters for directional PRS signals, precise location coordinates of WLAN APs and / or cellular base stations for use in OTDOA, AOD and / or ECID positioning, etc.) (which may be referred to as "UE-assisted" positioning) or may compute the position estimate itself (which may be referred to as "UE-based" positioning).

[0131] In one embodiment, UE 1200 may include a camera 1230 (e.g., front and / or back facing), such as a complementary metal oxide semiconductor (CMOS) image sensor with an appropriate lens configuration. Other imaging technologies such as charge coupled devices (CCDs) and back side emitting CMOS may be used. Camera 1230 may be configured to obtain and provide image information to assist in positioning of UE 1200. In an example, one or more external image processing servers (e.g., remote servers) may be used to perform image recognition and provide position estimation processing. UE 1200 may include other sensors 1235 that may also be used to calculate or to assist in calculating the position of UE 1200. Other sensors 1235 may include inertial sensors (e.g., accelerometers, gyroscopes, magnetometers, compasses, any of which may be implemented based on microelectromechanical systems (MEMS) or based on some other technology) as well as barometers, thermometers, hygrometers, and other sensors.

[0132] As mentioned, in some embodiments, UE 1200 may be configured to receive (e.g., via wireless transceiver 1221) a first directional positioning reference signal (PRS) transmitted by a first base station within at least one cell of the first base station, wherein the first directional PRS includes at least one signal characteristic and a transmission direction. In these embodiments, UE 1200 may be further configured to obtain at least one first measurement result of the first directional PRS based at least in part on the at least one signal characteristic, and facilitate position determination of UE 1200 based at least in part on the at least one first measurement result at a device with positioning capabilities (which may include UE 1200, and / or may further include the first base station, some other base station, a remote location server, etc.).

[0133] Substantial changes may be made depending on specific requirements. For example, customized hardware may also be used, and / or specific elements may be implemented in hardware, software (including portable software, such as applets, etc.), or both. In addition, connections to other computing devices (such as network input / output devices) may be employed.

[0134] A configuration may be described as a process depicted as a flow chart or block diagram. Although each may describe the operations as a sequential process, many of the operations may be performed in parallel or simultaneously. In addition, the order of the operations may be rearranged. The process may have additional steps not included in the figure. Furthermore, examples of the methods may be implemented by hardware, software, firmware, middleware, microcode, hardware description language, or any combination thereof. When implemented in software, firmware, middleware, or microcode, the program code or code segments to perform the necessary tasks may be stored in a non-transitory computer-readable medium, such as a storage medium. The processor may perform the described tasks.

[0135] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly or conventionally understood. As used herein, the article "a / an" refers to one or more than one (i.e., at least one) grammatical object of the article. By way of example, "an element" means one element or more than one element. When referring to measurable results such as amount, temporary duration and the like, "about" and / or "approximately" as used herein encompass changes compared to a specified value of ±20% or ±10%, ±5%, or +0.1%, because such changes are suitable for the context of systems, devices, circuits, methods and other implementations described herein. When referring to measurable results such as temporary duration, physical properties (e.g., frequency) and the like, "substantially" as used herein also encompasses changes compared to a specified value of ±20% or ±10%, ±5% or +0.1%, because such changes are suitable for the context of systems, devices, circuits, methods and other implementations described herein.

[0136] As used herein, "or" used in a list of items beginning with "at least one of" or "one or more of" as included in the claims indicates a disjunctive list, so that, for example, a list of "at least one of A, B, or C" means A or B or C or AB or AC or BC or ABC (i.e., A and B and C), or a combination of more than one feature (e.g., AA, AAB, ABBC, etc.). In addition, as used herein, unless otherwise stated, a statement that a function or operation is "based on" an item or condition means that the function or operation is based on the stated item or condition and may be based on one or more items and / or conditions other than the stated item or condition.

[0137] As used herein, a mobile device or station (MS) refers to a device, such as a cellular or other wireless communication device, a smart phone, a tablet computer, a personal communication system (PCS) device, a personal navigation device (PND), a personal information manager (PIM), a personal digital assistant (PDA), a laptop computer, or other suitable mobile devices capable of receiving wireless communication and / or navigation signals (e.g., navigation positioning signals). The term "mobile station" (or "mobile device" or "wireless device") is also intended to include devices that communicate with a personal navigation device (PND), such as through short-range wireless, infrared, wired connection, or other connection, regardless of whether satellite signal reception, auxiliary data reception, and / or positioning-related processing occurs at the device or at the PND. In addition, "mobile station" is intended to include all of the following devices, including wireless communication devices, computers, laptop computers, tablet computer devices, etc., which are capable of communicating with a server (e.g., via the Internet, WiFi, or other networks) and communicating with one or more types of nodes, regardless of whether satellite signal reception, auxiliary data reception, and / or positioning-related processing occurs at the device, at the server, or at another device or node associated with the network. Any operable combination of the above is also considered a "mobile station." A mobile device may also be referred to as a mobile terminal, terminal, user equipment (UE), device, secure user plane location enabled terminal (SET), target device, target or some other name.

[0138] Although some techniques, processes, and / or implementations presented herein may comply with all or part of one or more standards, in some embodiments, such techniques, processes, and / or implementations may not comply with part or all of such one or more standards.

[0139] Although specific embodiments have been disclosed in detail herein, this is done by way of example only for the purpose of illustration and is not intended to be limiting with respect to the scope of the following claims. In particular, it is contemplated that various substitutions, changes and modifications may be made without departing from the spirit and scope of the invention as defined by the claims. Other aspects, advantages and modifications should be considered to be within the scope of the following claims. The claims presented represent the embodiments and features disclosed herein. Other unclaimed embodiments and features are also covered. Therefore, other embodiments are within the scope of the following claims.

Claims

1. A mobile device, comprising: Memory; Transceiver; at least one processor operably coupled to the memory and the transceiver and configured to: receiving assistance data for a plurality of directional positioning reference signals, the assistance data comprising an identification and a transmit direction for each of the directional positioning reference signals, wherein a first directional positioning reference signal and a second directional positioning reference signal from the plurality of directional positioning reference signals are from a single cell and have different directions, wherein each direction corresponds to a different muting sequence; identifying one or more directional positioning reference signals to measure based at least in part on the respective identifications and transmit directions for the plurality of directional positioning reference signals; as well as One or more position measurements are determined based on the assistance data corresponding to the identified directional positioning reference signal and corresponding muting sequence. The mobile device of claim 1 , wherein the emission direction comprises a horizontal angle range. The mobile device of claim 1 , wherein the emission direction comprises a vertical angle range. 4 . The mobile device of claim 1 , wherein the at least one processor is further configured to receive a request for location information, wherein the request includes an identification of at least one of the one or more location measurements.

5. The mobile device of claim 1, wherein at least one of the one or more position measurements is a round trip time measurement.

6. The mobile device of claim 1, wherein at least one of the one or more location measurements comprises a cell identification.

7. The mobile device of claim 1, wherein at least one of the one or more location measurements comprises at least one of angle of arrival (AOA), time of arrival (TOA), reference signal time difference (RSTD), received signal strength indication (RSSI), reference signal received power (RSRP), and reference signal received quality (RSRQ).

8. The mobile device of claim 1, wherein the assistance data is received at the mobile device via a point-to-point protocol.

9. The mobile device of claim 1, wherein the at least one processor is further configured to provide at least one of the one or more location measurements to a server.

10. The mobile device of claim 1, wherein the at least one processor is further configured to select the one or more directional positioning reference signals based on a line of sight between a base station transmitting the one or more directional positioning reference signals and an expected location of the mobile device.

11. The mobile device of claim 1, wherein the transceiver comprises an antenna array, and the at least one processor is further configured to determine the one or more measurements utilizing the antenna array.

12. A method at a mobile device for supporting positioning of the mobile device, the method comprising: receiving assistance data for a plurality of directional positioning reference signals, the assistance data comprising an identification and a transmit direction for each of the directional positioning reference signals, wherein a first directional positioning reference signal and a second directional positioning reference signal from the plurality of directional positioning reference signals are from a single cell and have different directions, wherein each direction corresponds to a different muting sequence; identifying one or more directional positioning reference signals to measure based at least in part on the respective identifications and transmit directions for the plurality of directional positioning reference signals; as well as One or more position measurements are determined based on the assistance data corresponding to the identified directional positioning reference signal and corresponding muting sequence. The method of claim 12 , wherein the emission direction comprises a horizontal angle range. The method of claim 12 , wherein the emission direction comprises a vertical angular range.

15. The method of claim 12, further comprising receiving a request for location information, wherein the request comprises an identification of at least one of the one or more location measurements.

16. The method of claim 12, wherein at least one of the one or more position measurements is a round trip time measurement.

17. The method of claim 12, wherein at least one of the one or more location measurements comprises a cell identification.

18. The method of claim 12, wherein at least one of the one or more location measurements comprises at least one of angle of arrival (AOA), time of arrival (TOA), reference signal time difference (RSTD), received signal strength indication (RSSI), reference signal received power (RSRP), and reference signal received quality (RSRQ).

19. The method of claim 12, wherein the assistance data is received at the mobile device via a point-to-point protocol.

20. An apparatus for supporting positioning of a mobile device, comprising: means for receiving assistance data for a plurality of directional positioning reference signals, the assistance data comprising an identification and a transmit direction for each of the directional positioning reference signals, wherein a first directional positioning reference signal and a second directional positioning reference signal from the plurality of directional positioning reference signals are from a single cell and have different directions, wherein each direction corresponds to a different muting sequence; means for identifying one or more directional positioning reference signals to measure based at least in part on respective identifications and transmission directions for the plurality of directional positioning reference signals; as well as Means for determining one or more position measurements based on the assistance data corresponding to the identified directional positioning reference signal and corresponding muting sequence.

21. A non-transitory processor-readable storage medium comprising processor-readable instructions configured to cause one or more processors to support positioning of a mobile device, comprising: code for receiving assistance data for a plurality of directional positioning reference signals, the assistance data comprising an identification and a transmit direction for each of the directional positioning reference signals, wherein a first directional positioning reference signal and a second directional positioning reference signal from the plurality of directional positioning reference signals are from a single cell and have different directions, wherein each direction corresponds to a different muting sequence; code for identifying one or more directional positioning reference signals to measure based at least in part on respective identifications and transmission directions for the plurality of directional positioning reference signals; as well as Code for determining one or more position measurements based on the assistance data corresponding to the identified directional positioning reference signal and corresponding muting sequence.

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