WO2017164925A1 - Method of positioning for 5g systems - Google Patents

Abstract

A method is disclosed to obtain the position of an User Equipment (UE) with a high degree of accuracy in a cellular network. Operable within the UE, the positioning method performs Observed Time Difference of Arrival (OTDOA) or Enhanced Cellular Identification (E-CID) measurements using received beamformed Positioning Reference Signals (PRSs), using both the measurement information and novel beam information. The novel beam information includes an index of the beam(s), beam pointing angles (in both elevation and azimuth domains) relative to the bore-sight of the antenna of the transmitting device, and the relative orientation of the device antenna, whether of the UE or of an enhanced Node B base station (eNB), where the relative orientation is obtained using position sensors. The beam information, along with time of arrival measurements, is used to determine the position or improve the position accuracy of the UE.

Description

METHOD OF POSITIONING FOR 5G SYSTEMS

CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application claims priority to United States Provisional Patent Application No. 62/312,952, filed on March 24, 2016, which is incorporated herein by reference in its entirety.

TECHNICAL FIELD

[0002] This application relates to beams, location positioning, Observed Time Difference of Arrival, sensors, and other enhanced 911 issues under the Third Generation Partnership Project (3GPP).

BACKGROUND

[0003] The Evolved Packet Core (EPC) is the core network of advanced mobile communication systems. The EPC allows different radio access technologies (RATs) to operate in an integrated manner. These radio access technologies include first generation wireless Local Area Networks (LANs), second generation (2G) systems, such as Global System for Mobile communication, or GSM, third generation (3G) systems, such as the Universal Mobile Telecommunication System (UMTS), and fourth generation (4G) systems, such as Long Term Evolution (LTE). LTE continues to evolve (e.g., LTE-Advanced, or LTE-A) and many new features are referred to as fifth generation (5G) technology.

[0004] Figure 1 is a basic architecture of an Evolved Packet System (EPS) 80. An User Equipment (UE) 50, also known as a terminal, connects to the EPC 70 over the LTE access network known as E-UTRAN (short for Evolved UMTS Terrestrial Radio Access Network) 44 and communicates with a base station known as the Evolved Node B (eNB) 40, where the eNB may refer collectively to one or more base stations and/or radio heads. The EPS 80 generally refers to a complete system consisting of the UE 50, the E-UTRAN 44, and the core network (EPC) 70. The EPC 70 is a packet-switched network in which the Internet Protocol (IP) is used for all transport services. The EPC is part of the 3^rd Generation Partnership Project (3GPP) specification. [0005] The EPC 70 consists of a Serving Gateway (S-GW) 30, a Packet Data Network Gateway (P-GW) 32, a Mobility Management Entity (MME) 34, and a Home Subscriber Server (HSS) 36. The EPC 70 connects to external networks 38, in this case, including an Internet protocol Multimedia Subsystem (IMS) 42. User data and signaling are independent, with user data occupying a user plane (solid lines) and signaling occupying a control plane (dashed lines).

[0006] In the United States and Canada, the "91 1 " telephone number, designed for emergency use, was developed in 1968, and became widespread in the 1970s and 1980s. A person dials "911 " on his/her telephone and a dispatcher services the call, which may include sending police, fire, or other emergency personnel to the location of the calling individual. "Enhanced 91 1 " or "E911 " refers to the feature in which the 91 1 dispatcher automatically receives location information of the caller, if available. Typically, for landline phones, the location information is available, while, for mobile devices, no location information is provided to the dispatcher.

[0007] The Federal Communications Commission (FCC) requires all mobile operators in the United States to comply with the following E91 1 location requirements for outdoor locations:

• 67% of emergency calls should be located with an accuracy of 50 meters (m)

• 80% of emergency calls should be located with an accuracy of 150 m (increasing to 90% in six years)

[0008] Location Based Services (LBS) involves determining the location of a device, and may be useful to 91 1 dispatchers. One satellite- based LBS is known as Global Navigation Satellite System (GNSS). Global Positioning System (GPS) and GLObal NAvigation Satellite System (GLONASS) are two GNSS-based systems. GNSS-based capability is available in most LTE devices.

[0009] GNSS-based LBS, however, only works well when the UE has a good line-of-sight to the satellite. Where the satellite signals are blocked, GNSS will not work. GNSS thus fails in dense urban environments and inside buildings. [0010] The FCC is now proposing to extend E91 1 to automatically supply location information to dispatchers when calls are received from indoor locations. In addition, the FCC requires that vertical location information (z axis) be provided within 3 meters of the caller for 67% of indoor locations (increasing to 80% in five years). Since Radio Access Technology (RAT) signals have higher received power relative to GNSS signals, RAT-based location services are starting to receive higher attention in the industry to meet these requirements. GNSS alone is insufficient to satisfy the new FCC requirements.

[0011] Thus, a mechanism is desired to overcome the shortcomings of the prior art.

BRIEF DESCRIPTION OF THE DRAWINGS

[0012] The foregoing aspects and many of the attendant advantages of this document will become more readily appreciated as the same becomes better understood by reference to the following detailed description, when taken in conjunction with the accompanying drawings, wherein like reference numerals refer to like parts throughout the various views, unless otherwise specified.

[0013] Figure 1 is a diagram of an Evolved Packet System architecture with E-UTRAN access;

[0014] Figure 2 illustrates the mapping of position reference signals with one or two PBCH ports and with four PBCH ports, for both normal and extended cyclic prefix;

[0015] Figure 3 illustrates an Observed Time Difference of Arrival (OTDOA) technique for determining position of a device using three devices of known positions;

[0016] Figure 4 is a simplified diagram illustrating how E-CID is improved by using multiple measurements;

[0017] Figure 5 illustrates an architecture for network positioning under the Long-Term Evolution standard;

[0018] Figure 6 illustrates the multiple links established between an enhanced base station and a user equipment when beamforming is employed; [0019] Figure 7 is a simplified block diagram of a positioning method to facilitate position location of a user equipment, according to some embodiments;

[0020] Figure 8 is an illustration of the difference between elevation and azimuth, used to calculate position location of a user equipment relative to an enhanced base station in the positioning method of Figure 7, according to some embodiments;

[0021] Figure 9 is an illustration of a distance calculation between a user equipment and an enhanced base station used by the positioning method of Figure 7, according to some embodiments;

[0022] Figure 10 illustrates how multiple communication links and beam directions between the user equipment and a single enhanced base station are exploited by the positioning method of Figure 7, according to some embodiments;

[0023] Figure 1 1 is a simplified block diagram of a UE capable of implementing the positioning method of Figure 7, according to some embodiments.

[0024] DETAILED DESCRIPTION

[0025] In accordance with the embodiments described herein, a method is disclosed to obtain the position of an User Equipment (UE) with a high degree of accuracy in a cellular network. Operable within the UE, the positioning method performs Observed Time Difference of Arrival (OTDOA) or Enhanced Cellular Identification (E-CID) measurements using received beamformed Positioning Reference Signals (PRSs), using both the measurement information and novel beam information. The novel beam information includes an index of the beam(s), beam pointing angles (in both elevation and azimuth domains) relative to the bore-sight of the antenna of the transmitting device, and the relative orientation of the device antenna, whether of the UE or of an enhanced Node B base station (eNB), where the relative orientation is obtained using position sensors. The beam information, along with time of arrival measurements, is used to determine the position or improve the position accuracy of the UE. Measurements taken from multiple communication links between the UE and the eNB enable the position of the UE to be obtained more accurately

[0026] In the following detailed description, reference is made to the accompanying drawings, which show by way of illustration specific embodiments in which the subject matter described herein may be practiced. However, it is to be understood that other embodiments will become apparent to those of ordinary skill in the art upon reading this disclosure. In other instances, well-known structures, materials, or operations are not shown or described in detail to avoid obscuring aspects of the invention. The following detailed description is, therefore, not to be construed in a limiting sense, as the scope of the subject matter is defined by the claims.

[0027] LTE-based location services

[0028] Location Based Services (LBS) are familiar to many mobile device users, used for map services, finding friends nearby, and other features. LBS enable the location, or position, of the mobile device, to be obtained by the software providing these features.

[0029] Some LBS employ multilateration, a navigation technique based on measuring the difference in distance to two objects at known locations that broadcast signals at known times. The resulting locations form a hyperbolic curve. Additional measurements taken with additional objects cause a second hyperbolic curve, which intersects with the first hyperbolic curve, resulting in a fix of the location.

[0030] The current LTE standard supports three independent positioning techniques: Assisted Global Navigation Satellite Systems (A- GNSS), Observed Time Difference of Arrival (OTDOA), and Enhanced Cell Identifier (E-CID). Combinations of these techniques may also be used.

[0031] Assisted Global Navigation Satellite Systems (A- GNSS)

[0032] Global Navigation Satellite Systems (GNSS), such as GPS, are based on satellite-based position estimation. Most mobile devices include an integrated GNSS receiver. At least four satellites, each with an unobstructed line-of-sight to the UE, enable estimation of the UE's position. Using its GPS chip (GNSS receiver), the UE makes a connection to the satellites. GPS operations are time-consuming and are unavailable in dense urban environments or inside buildings.

[0033] Assisted GNSS (A-GNSS) improves the receipt of location information by the UE because the serving eNB makes the initial connection with the satellites and stores the information obtained. The eNB then provides the data to the GNSS receiver. This data includes Almanac and/or Ephemeris data. Almanac data contains coarse orbital parameters from all global navigation satellites, and is updated infrequently. Ephemeris data, by contrast, uses clock correction to obtain very precise location information, which is broadcast by each satellite every 30 seconds. The position calculations, based on the assistance data, can be made by other network entities besides the UE. Nevertheless, A-GNSS is problematic inside buildings and in dense urban environments, due to the unavailability of a line- of-sight satellite signal at the UE.

[0034] Positioning Reference Signals (PRS)

[0035] In LTE Release 9, positioning functionality is enhanced by the introduction of Positioning Reference Signals (PRS). Figure 2 is a diagram showing the mapping of PRS in a resource block, for both normal and extended cyclic prefix, for one or two Physical Broadcast Channel (PBCH) antenna ports, and for four PBCH antenna ports, respectively (taken from 3GPP TS 36.211 version 10.0.0 Release 10, Section 6.10.4). PRS are transmitted on antenna port 6, in downlink subframes configured for positioning reference signal transmission. The PRS enable the terminal (UE) to perform measurements on one or more LTE cells (eNBs) to estimate the geographical position of the terminal.

[0036] PRS are defined by bandwidth, offset, duration (the number of consecutive subframes), and periodicity. The PRS are configured to the UE via higher layer signaling by providing these characteristics: the carrier index where PRS is transmitted, the PRS bandwidth, the number of consecutive subframes for PRS transmissions, PRS transmission periodicity/subframe offset, and the PRS muting sequence. The PRS bandwidth is smaller than the system bandwidth, and PRS are mapped around the carrier frequency. Typically, no PDSCH is transmitted in a subframe where PRS are configured. PRS can be muted to reduce inter-cell interference as needed.

[0037] A-GNSS described above predates the implementation of positioning reference signals, but PRS are used for both OTDOA and E-CID location services, as described below.

[0038] Observed Time Difference of Arrival (OTDOA)

[0039] OTDOA is similar to GPS and other A-GNSS-based location services, but, instead of taking measurements from satellites, the UE obtains measurements from eNBs in its proximity, including the base station communicating with the UE (known as its serving eNB), as well as neighboring eNBs.

[0040] Under the OTDOA positioning technique, the UE measures the time difference between PRS transmitted by its serving eNB, and those of at least two neighboring eNBs. The UE calculates a Reference Signal Time Difference (RSTD) by measuring a time difference between the PRS of a neighboring cell and the PRS of its serving cell; a second time difference is measured between the PRS of a second neighboring cell and the PRS of its serving cell. Unlike the GPS satellites orbiting the earth at high speed used to calculate location, the network knows the location of the eNBs and this enables the UE location to be obtained, relative to the eNBs, using these RSTDs.

[0041] Figure 3 illustrates the OTDOA positioning technique. A UE 50 is located closest to its serving eNB 40, but neighboring eNBs 40A and 40B are within range of the UE. The UE calculates a first RSTD (RSTD_Ni ) by measuring the time difference between receipt of PRS from neighboring cell A (TRX NA) and the serving cell (T_Rx__Serving); the UE calculates a second RSTD (RSTDN2) by measuring the time difference between receipt of PRS from neighboring cell B (T_RX__NB) and the serving cell (T_Rx__Serving)- Both measurements are reported to a location server, which calculates the UE position based on the received measurements, RSTDNI and RSTDN2-

[0042] The network assists the UE by providing the relative transmission time differences of each neighbor cell relative to the serving cell. Location servers in the network know the exact position of each eNB transmit antenna, and can provide candidate neighboring cells to the UE, thus limiting the search space and increasing the speed of measurements taken.

[0043] Enhanced Cell Identifier (E-CID)

[0044] Another method for position estimation in LTE is Enhanced Cell ID (E-CID). Under this method, the position of the UE is estimated based on the location of its serving eNB, which can be obtained by executing a tracking area update or by paging. Thus, the position of the UE is known relative to the eNB and is linked to the size of the cell coverage area of the eNB. To get more accurate information, additional measurements can be obtained as follows:

• E-CID with estimating the distance from a single base station

• E-CID with measuring the distance from three base stations

• E-CID by measuring the Angle-of-Arrival (AoA) from at least two (or three) base stations

[0045] The measurements help to find the location of the UE within the cell with more precision. The measurements may consist of a Reference Signal Received Power (RSRP), a Time Difference of Arrival (TDOA) and the measurement of the Timing Advance (TA), or a Round Trip Time (RTT), from the serving eNB. RSRP is the average power of Resource Elements (REs) that carry PRS over the entire bandwidth. TDOA is obtained by measuring the time of arrival of synchronized signals (such as the PRS) at physically separate locations. TA is the length of time a signal takes to reach the eNB from the UE. Commonly used TA measurements are type 1 , summing the eNB and UE receive-transmit time differences, and type 2, a measurement taken by the eNB during a UE Random Access procedure.

[0046] The TA type 1 measurement corresponds to the RTT. With type 1 TA measurements, for example, the sum of the receive-transmit timing difference at the eNB (positive or negative value) and the receive- transmit timing difference at the UE (always a positive value) is taken. The measurement is reported to the location server, where the distance between the UE and the eNB is half the RTT multiplied by the speed of light.

[0047] In the first E-CID option, the position of the UE is obtained by estimating the distance of the UE from the serving eNB (whose location is known by the network). The estimate measures a RSRP, a TA, or an RTT, from the serving eNB. Thus, the first E-CID option results in a circle around the eNB (coarse position).

[0048] In the second E-CID option, the RSRP, TA, or the RTT from each of three eNBs is measured (where the location of each eNB is known to the network). For the second E-CID option, the position accuracy is much finer than a circle around the eNB and is instead a point within the cell.

[0049] The third option is distinguishable from the first two in that measurements are taken by the eNBs, rather than the UE. Two (or three) eNBs, including the serving eNB, obtain an Angle-of Arrival (AoA) measurement to the network, where a location server, the serving eNB, or a combination of eNBs performs the calculations, resulting in the location of the UE being obtained. Each of the two or three eNBs estimates the direction from which the UE is transmitting using a linear array of equally spaced antenna elements. The PRS received from the UE at any two adjacent elements are phase rotated by an amount that depends on the angle of arrival, the carrier frequency, and the element spacing.

[0050] In the first and second options, the measurements are taken by the UE and based on RSRP, TA, or RTT estimations. In the third option, the measurements are taken directly by the eNB.

[0051] Figure 4 is a simplified diagram illustrating how E-CID is improved by using multiple measurements. For simplicity, just one base station is shown. Where basic E-CID is used, the position of all UEs in the cell area is coarsely known, and is essentially a circle around the eNB; with E- CID plus RTT, UEs that are a measured distance from the eNB are located; with E-CID plus RTT plus AoA, the position of the UE can be obtained with the most precision.

[0052] LTE architecture for Location Based Services

[0053] Figure 5 shows the high-level LTE location architecture 200 for location services. Many of the entities of the EPS 80 in Figure 1 , such as the S-GW 30, the P-GW 32, the MME 34, the eNB 40, and the UE 50 are similarly found in the LTE location architecture 200. Additionally, a location server 90 includes an Evolved Serving Mobile Location Center (E-SMLC) 52 and a Secure User Plane Location (SULP) Location Platform (SLP) 54, connects to the eNB 40 either through the MME 34 or through the Serving Gateway (S-GW) 30 and Packet Data Network Gateway (P-GW) 32.

[0054] The UE 50 and eNB 40 can communicate with the location server 90 in one of two ways, via a User Plane (U-Plane, solid lines) or a Control Plane (C-Plane, dotted lines). In the C-Plane, an LBS session is established and assistance data message exchange is performed over the control channels. C-Plane signaling is considered more reliable and robust than U-Plane signaling, and may overcome network congestion in an emergency situation. LTE Positioning Protocol (LPP) is the protocol used for C-Plane LBS sessions. In the C-Plane, the E-SMLC is the location server.

[0055] In the U-Plane, the data link is used as the bearer for handling LBS sessions and for transport of the assistance data messages. Map services, for example, use the U-Plane, due to the large amount of data transfer, as control channels do not typically support large volumes of data. For the U-Plane, the SLP 54 provides location services. SUPL is a positioning protocol defined by the Open Mobile Alliance. The location server 90 is a physical or logical entity that collects measurement data and other location information from the UE 50 and/or the eNB 40, and assists with measurements and estimation of the UE's position.

[0056] 5G MIMO

[0057] The 5G Multiple-lnput-Multiple-Output (MIMO) systems will rely on the beamforming concept for signal transmission and reception. Beamforming is the shaping of the overall antenna beam in the direction of the receiver. Beamforming uses multiple antennas (such as an antenna array) to control the direction of a signal by weighing the magnitude and phase of individual antenna signals. The reference signals transmitted by the eNB are likely to be beamformed using multiple antennas to provide sufficient coverage of the transmission in a certain beam direction. The beamforming can be performed in the digital and/or analog domains.

[0058] The UE may also apply beamforming on the receiving antennas and, based on the measurements from the received reference signal, may choose and indicate to the eNB the most dominant beams set, which are preferred from the communication perspective. As a result, multiple possible communication links can be established between the UE and the eNB, where each communication link can be associated with the pair of transmit and receive beams.

[0059] The most preferred communication links may correspond to the line-of-sight path of the channel or to the first order reflection path. Figure 6 illustrates one scenario of possible communication links between the eNB 40 and the UE 50. Beams 1 , 2, and 3, are transmitted by the eNB in the general direction of the UE, with receive beams 4, 5, and 6 at the UE to receive the PRS signal. Objects 58 and 68, which may be buildings, walls, or other solid objects off which a signal may be reflected. Link 1 is a line-of-sight (LOS) path in which the PRS signal transmitted via beam 1 at the eNB 40 is received at beam 4 at the UE 50. The PRS signal transmitted via beam 2 at the eNB is deflected off object 58, resulting in a first order reflection path (link 2) received via beam 5 at the UE. The PRS signal transmitted via beam 3 at the eNB is deflected off object 68, resulting also in a first order reflection path (link 3) received via beam 6 at the UE.

[0060] Positioning Method 100

[0061] Figure 7 is a simplified block diagram of a positioning method 100 to enable a UE in a cellular network to coordinate with other entities in obtaining and communicating position information of the UE. In some embodiments, the positioning method 100 is suitable for UEs that include New Radio features (e.g., 5G-capable mobile devices). The positioning method 100 involves the processing at the serving eNB 40, the UE 50, and the location server 90, all of which are part of a cellular network.

[0062] Further, in some embodiments, the positioning method 100 is part of a global coordinate system. The global coordinate system is a coordinate system that is common to the UE and all eNBs that are involved in the positioning of the UE. The global coordinate system is thus used in the beam direction context. This enables the beam direction and beam angles to be defined in terms of a common coordinate system.

[0063] For example, all beam directions can be measured in the azimuth domain relative to the north direction (which is common for the relevant eNBs and the UE). Similarly, the elevation direction can be measured relative to the zenith direction (which should also be common for the relevant eNBs and the UE). In order to get the beam orientation for such global coordinate system, the device should know the orientation of the antenna array in the global coordinate system and the orientation of the beam in a local coordinate system of the antenna array. The beam orientation in the local coordinate system of the antenna array is typically known from the beamforming weights. The antenna array orientation in the global coordinate system can be obtained from sensor measurements (at the UE) or known in advance (e.g., at a fixed location in the eNBs).

[0064] The positioning method 100 commences once the eNB 40 transmits positioning reference signals with beamforming 56 over one or more communication links. The UE implementing the positioning method 100 includes a beam information calculation unit 60 and a measurement information calculation unit 74 In some embodiments, the UE uses the received beamformed PRS 56, along with position sensors 64, to supply beam information 62 and measurement information 72 to the location server 90.

[0065] In some embodiments, the beam information 62 includes the index of the beam, beam pointing angles (in both the elevation and azimuth domains) of the links relative to the bore-sight of the antenna of the device (either the UE or the eNB(s)), and the bore-sight direction of the antenna in the global coordinate system. In some embodiments, the position sensors 64 provide orientation of the antenna array in the global coordinate system.

[0066] Figure 8 illustrates the difference between elevation and azimuth. Elevation and azimuth define the position of an object, relative to another object, at a particular time. Elevation, also known as altitude, is a measure of the angle between an object and the observer's location horizon. In Figure 8, the elevation is the angle between the top of the eNB 40 relative to the horizon of the UE 50. Azimuth is the angle of the object around the horizon measured relative to the north position, measured clockwise around the observer's horizon. In Figure 8, the azimuth is obtained by drawing a line between the eNB 40 and the UE 50, then measuring the angle of this line relative to north (N). These two angles, elevation and azimuth, are part of the beam information 62 provided to the location server 90 by the UE 50.

[0067] The beam information may also include the relative orientation of the device antenna in the global coordinate system. Position sensors 64 in the UE 50 are able to obtain the relative orientation of the antenna. A position sensor is a device that enables a position of an object to be measured. Position sensors, which may include orientation sensors and/or magnetometers, measure the physical position of a device and therefore may provide information to the location server 90 about pointing directions of the beams in the global coordinate systems. Magnetometers measure the direction of the magnetic field at a point in space. The beam direction information, along with time of arrival measurements, can be used to determine or improve the position accuracy of the UE. The orientation of the antenna of the eNB(s) is usually fixed and can be determined during the deployment.

[0068] The physical position of the device along with beam direction corresponding to the link relative to the device can be used to improve the positioning accuracy in various ways. For example, the estimation of the distance to the transmitting device can be improved by taking into account the beam angles of the link.

[0069] Such an improvement is illustrated with the simplified diagram of Figure 9, consisting of the UE 50 and the eNB 40, as before. A communication link, d, where d = a + b, is a first order reflection path resulting from the presence of a solid object (see Figure 6), and is indicated with a thick black line. For simplicity, a two-dimensional case is considered. However, the positioning method 100 as described herein can be extended to three dimensions.

[0070] Based on the time of arrival measurements using the reference signal transmitted over the link, the propagation length, d, of the link can be estimated. By using the beam pointing angles β and γ corresponding to the link, the actual distance, x, between the UE and the eNB can be estimated as follows:

[0072] Thus, in situations where the beam directions at the eNB

40 and the UE 50 are known, the distance, x, between the UE and the eNB can be calculated more accurately in spite of the reflection of the channel paths.

[0073] In other embodiments, the multiple communication links and beam directions can be also used to constructively increase the effective number of measured sources. Thus, each communication link may be considered as an additional transmission source. Three communication links are illustrated in Figure 10, a line-of-sight link (link 1 ), a first order reflection path caused by object 58 (link 2), and a second first order reflection path caused by object 68 (link 3). The positioning method 100 treats the three links as though they came from three transmitting base stations, known as effective eNBs or virtual eNBs. In some embodiments, the position of each effective base station (eNB 40A and eNB 40B) is obtained from the time arrival measurements and angular information of the beams.

[0074] The exploitation of the first order reflection paths by the positioning method 100 is useful particularly in rural environments, where the deployment of base stations is costly and thus the distance between base stations may be long and therefore cells tend to be larger and neighboring cells may not be detected by the UE.

[0075] Thus, the position method 100 enables the position of the UE 50 to be obtained by the location server 90 using PRS transmission from a single transmission point over multiple communication links.

[0076] Operating Environment

[0077] Various techniques, or certain aspects or portions thereof, may take the form of program code (i.e., instructions) embodied in tangible media, such as floppy diskettes, CD-ROMs, hard drives, non- transitory computer readable storage medium, or any other machine-readable storage medium wherein, when the program code is loaded into and executed by a machine, such as a computer, the machine becomes an apparatus for practicing the various techniques. A non-transitory computer-readable storage medium can be a computer-readable storage medium that does not include a signal. In the case of program code execution on programmable computers, the computing device may include a processor, a storage medium readable by the processor (including volatile and non-volatile memory and/or storage elements), at least one input device, and at least one output device. The volatile and non-volatile memory and/or storage elements may be a RAM, EPROM, flash drive, optical drive, magnetic hard drive, solid state drive, or other medium for storing electronic data. The node and wireless device may also include a transceiver module, a computer module, a processing module, and/or a clock module or timer module. One or more programs that may implement or utilize the various techniques described herein may use an application programming interface (API), reusable controls, and the like. Such programs may be implemented in a high-level procedure or object-oriented programming language to communicate with a computer system. However, the program(s) may be implemented in assembly or machine language, if desired. In any case, the language may be a compiled or interpreted language, and combined with hardware implementations.

[0078] It should be understood that many of the functional units described in the specification have been labeled as modules, in order to more particularly emphasize their implementation independence. For example, a module may be implemented as a hardware circuit comprising custom VLSI circuits or gate arrays, off-the-shelf semiconductors such as logic chips, transistors, or other discrete components. A module may also be implemented in programmable hardware devices such as field programmable gate arrays, programmable array logic, programmable logic devices, or the like.

[0079] Modules may also be implemented in software for execution by various types of processors. An identified module of executable code may, for instance, comprise one or more physical or logical blocks of computer instructions, which may, for instance, be organized as an object, procedure, or function. Nevertheless, the executables of an identified module need not be physically located together, but may comprise disparate instructions stored in different locations which, when joined logically together, comprise the module and achieve the stated purpose for the module. [0080] Indeed, a module of executable code may be a single instruction, or many instructions, and may even be distributed over several different code segments, among different programs, and across several memory devices. Similarly, operational data may be identified and illustrated herein within modules, and may be embodied in any suitable form and organized within any suitable type of data structure. The operational data may be collected as a single data set, or may be distributed over different locations including over different storage devices, and may exist, at least partially, merely as electronic signals on a system or network. The modules may be passive or active, including agents operable to perform desired functions.

[0081] Reference throughout this specification to "an example" means that a particular feature, structure, or characteristic described in connection with the example is included in at least one embodiment of the present invention. Thus, appearances of the phrases, "in an example" or "in some embodiments" in various places throughout this specification are not necessarily all referring to the same embodiment.

[0082] As used herein, a plurality of items, structural elements, compositional elements, and/or materials may be presented in a common list for convenience. However, these lists should be construed as though each member of the list is individually identified as a separate and unique member. Thus, no individual member of such list should be construed as a de facto equivalent of any other member of the same list solely based on their presentation in a common group without indications to the contrary. In addition, various embodiments and examples of the present invention may be referred to herein along with alternatives for the various components thereof. It is understood that such embodiments, examples, and alternatives are not to be construed as de facto equivalents of one another, but are to be considered as separate and autonomous representations of the present invention. Furthermore, the described features, structures, or characteristics may be combined in any suitable manner in one or more embodiments.

[0083] As used herein, the term "circuitry" may refer to, be part of, or include an ASIC, an electronic circuit, a processor (shared, dedicated, or group), and/or memory (shared, dedicated, or group) that execute one or more software or firmware programs, a combinational logic circuit, and/or other suitable hardware components that provide the described functionality. In some embodiments, the circuitry may be implemented in, or functions associated with the circuitry may be implemented by, one or more software or firmware modules. In some embodiments, circuitry may include logic, at least partially operable in hardware.

[0084] Embodiments described herein may be implemented into a system using any suitably configured hardware and/or software. Figure 1 1 illustrates, for one embodiment, example components of a User Equipment (UE) device 800 that may implement the positioning method 100 described above. In some embodiments, the UE device 800 may include application circuitry 802, baseband circuitry 804, Radio Frequency (RF) circuitry 806, front-end module (FEM) circuitry 808 and one or more antennas 810, coupled together at least as shown.

[0085] The application circuitry 802 may include one or more application processors. For example, the application circuitry 802 may include circuitry such as, but not limited to, one or more single-core or multi- core processors. The processor(s) may include any combination of general- purpose processors and dedicated processors (e.g., graphics processors, application processors, etc.). The processors may be coupled with and/or may include a storage medium 812 or other type of memory/storage and may be configured to execute instructions stored in the memory/storage to enable various applications and/or operating systems to run on the system.

[0086] The baseband circuitry 804 may include circuitry such as, but not limited to, one or more single-core or multi-core processors. The baseband circuitry 804 may include one or more baseband processors and/or control logic to process baseband signals received from a receive signal path of the RF circuitry 806 and to generate baseband signals for a transmit signal path of the RF circuitry 806. Baseband processing circuity 804 may interface with the application circuitry 802 for generation and processing of the baseband signals and for controlling operations of the RF circuitry 806. For example, in some embodiments, the baseband circuitry 804 may include a second generation (2G) baseband processor 804A, third generation (3G) baseband processor 804B, fourth generation (4G) baseband processor 804C, and/or other baseband processor(s) 804D for other existing generations, generations in development, or to be developed in the future (e.g., fifth generation (5G), 6G, etc.). The baseband circuitry 804 (e.g., one or more of baseband processors 804A - D) may handle various radio control functions that enable communication with one or more radio networks via the RF circuitry 806. The radio control functions may include, but are not limited to, signal modulation/demodulation, encoding/decoding, radio frequency shifting, etc. In some embodiments, modulation/demodulation circuitry of the baseband circuitry 804 may include Fast-Fourier Transform (FFT), precoding, and/or constellation mapping/demapping functionality. In some embodiments, encoding/decoding circuitry of the baseband circuitry 804 may include convolution, tail-biting convolution, turbo, Viterbi, and/or Low Density Parity Check (LDPC) encoder/decoder functionality. Embodiments of modulation/demodulation and encoder/decoder functionality are not limited to these examples and may include other suitable functionality in other embodiments.

[0087] In some embodiments, the baseband circuitry 804 may include elements of a protocol stack such as, for example, elements of an EUTRAN protocol including, for example, physical (PHY), media access control (MAC), radio link control (RLC), packet data convergence protocol (PDCP), and/or radio resource control (RRC) elements. A central processing unit (CPU) 804E of the baseband circuitry 804 may be configured to run elements of the protocol stack for signaling of the PHY, MAC, RLC, PDCP, and/or RRC layers. In some embodiments, the baseband circuitry may include one or more audio digital signal processor(s) (DSP) 804F. The audio DSP(s) 804F may include elements for compression/decompression and echo cancellation and may include other suitable processing elements in other embodiments. Components of the baseband circuitry may be suitably combined in a single chip, a single chipset, or disposed on a same circuit board in some embodiments. In some embodiments, some or all of the constituent components of the baseband circuitry 804 and the application circuitry 802 may be implemented together such as, for example, on a system on a chip (SOC).

[0088] In some embodiments, the baseband circuitry 804 may provide for communication compatible with one or more radio technologies. For example, in some embodiments, the baseband circuitry 804 may support communication with an EUTRAN and/or other wireless metropolitan area networks (WMAN), a wireless local area network (WLAN), or a wireless personal area network (WPAN). Embodiments in which the baseband circuitry 804 is configured to support radio communications of more than one wireless protocol may be referred to as multi-mode baseband circuitry.

[0089] RF circuitry 806 may enable communication with wireless networks using modulated electromagnetic radiation through a non-solid medium. In various embodiments, the RF circuitry 806 may include switches, filters, amplifiers, etc., to facilitate the communication with the wireless network. RF circuitry 806 may include a receive signal path which may include circuitry to down-convert RF signals received from the FEM circuitry 808 and provide baseband signals to the baseband circuitry 804. RF circuitry 806 may also include a transmit signal path which may include circuitry to up- convert baseband signals provided by the baseband circuitry 804 and provide RF output signals to the FEM circuitry 808 for transmission.

[0090] In some embodiments, the RF circuitry 806 may include a receive signal path and a transmit signal path. The receive signal path of the RF circuitry 806 may include mixer circuitry 806A, amplifier circuitry 806B and filter circuitry 806C. The transmit signal path of the RF circuitry 806 may include filter circuitry 806C and mixer circuitry 806A. RF circuitry 806 may also include synthesizer circuitry 806D for synthesizing a frequency for use by the mixer circuitry 806A of the receive signal path and the transmit signal path. In some embodiments, the mixer circuitry 806A of the receive signal path may be configured to down-convert RF signals received from the FEM circuitry 808 based on the synthesized frequency provided by synthesizer circuitry 806D. The amplifier circuitry 806B may be configured to amplify the down-converted signals and the filter circuitry 806C may be a low-pass filter (LPF) or band-pass filter (BPF) configured to remove unwanted signals from the down-converted signals to generate output baseband signals. Output baseband signals may be provided to the baseband circuitry 804 for further processing. In some embodiments, the output baseband signals may be zero-frequency baseband signals, although this is not a requirement. In some embodiments, mixer circuitry 806A of the receive signal path may comprise passive mixers, although the scope of the embodiments is not limited in this respect.

[0091] In some embodiments, the mixer circuitry 806A of the transmit signal path may be configured to up-convert input baseband signals based on the synthesized frequency provided by the synthesizer circuitry 806D to generate RF output signals for the FEM circuitry 808. The baseband signals may be provided by the baseband circuitry 804 and may be filtered by filter circuitry 806C. The filter circuitry 806C may include a low-pass filter (LPF), although the scope of the embodiments is not limited in this respect.

[0092] In some embodiments, the mixer circuitry 806A of the receive signal path and the mixer circuitry 806A of the transmit signal path may include two or more mixers and may be arranged for quadrature downconversion and/or upconversion, respectively. In some embodiments, the mixer circuitry 806A of the receive signal path and the mixer circuitry 806A of the transmit signal path may include two or more mixers and may be arranged for image rejection (e.g., Hartley image rejection). In some embodiments, the mixer circuitry 806A of the receive signal path and the mixer circuitry may be arranged for direct downconversion and/or direct upconversion, respectively. In some embodiments, the mixer circuitry 806A of the receive signal path and the mixer circuitry of the transmit signal path may be configured for super-heterodyne operation.

[0093] In some embodiments, the output baseband signals and the input baseband signals may be analog baseband signals, although the scope of the embodiments is not limited in this respect. In some alternate embodiments, the output baseband signals and the input baseband signals may be digital baseband signals. In these alternate embodiments, the RF circuitry 806 may include analog-to-digital converter (ADC) and digital-to- analog converter (DAC) circuitry and the baseband circuitry 804 may include a digital baseband interface to communicate with the RF circuitry 806.

[0094] In some dual-mode embodiments, a separate radio IC circuitry may be provided for processing signals for each spectrum, although the scope of the embodiments is not limited in this respect.

[0095] In some embodiments, the synthesizer circuitry 806D may be a fractional-N synthesizer or a fractional N/N+1 synthesizer, although the scope of the embodiments is not limited in this respect as other types of frequency synthesizers may be suitable. For example, synthesizer circuitry 806D may be a delta-sigma synthesizer, a frequency multiplier, or a synthesizer comprising a phase-locked loop with a frequency divider.

[0096] The synthesizer circuitry 806D may be configured to synthesize an output frequency for use by the mixer circuitry 806A of the RF circuitry 806 based on a frequency input and a divider control input. In some embodiments, the synthesizer circuitry 806D may be a fractional N/N+1 synthesizer.

[0097] In some embodiments, frequency input may be provided by a voltage controlled oscillator (VCO), although that is not a requirement. Divider control input may be provided by either the baseband circuitry 804 or the applications processor 802 depending on the desired output frequency. In some embodiments, a divider control input (e.g., N) may be determined from a look-up table based on a channel indicated by the applications processor 802.

[0098] Synthesizer circuitry 806D of the RF circuitry 806 may include a divider, a delay-locked loop (DLL), a multiplexer, and a phase accumulator. In some embodiments, the divider may be a dual modulus divider (DMD) and the phase accumulator may be a digital phase accumulator (DPA). In some embodiments, the DMD may be configured to divide the input signal by either N or N+1 (e.g., based on a carry out) to provide a fractional division ratio. In some example embodiments, the DLL may include a set of cascaded, tunable, delay elements, a phase detector, a charge pump, and a D-type flip-flop. In these embodiments, the delay elements may be configured to break a VCO period up into N_d equal packets of phase, where N_d is the number of delay elements in the delay line. In this way, the DLL provides negative feedback to help ensure that the total delay through the delay line is one VCO cycle.

[0099] In some embodiments, synthesizer circuitry 806D may be configured to generate a carrier frequency as the output frequency, while in other embodiments, the output frequency may be a multiple of the carrier frequency (e.g., twice the carrier frequency, four times the carrier frequency), and used in conjunction with quadrature generator and divider circuitry to generate multiple signals at the carrier frequency with multiple different phases with respect to each other. In some embodiments, the output frequency may be a LO frequency (fi_o)- In some embodiments, the RF circuitry 806 may include an IQ/polar converter.

[00100] FEM circuitry 808 may include a receive signal path which may include circuitry configured to operate on RF signals received from one or more antennas 810, amplify the received signals and provide the amplified versions of the received signals to the RF circuitry 806 for further processing. FEM circuitry 808 may also include a transmit signal path which may include circuitry configured to amplify signals for transmission provided by the RF circuitry 806 for transmission by one or more of the one or more antennas 810.

[00101] In some embodiments, the FEM circuitry 808 may include a TX/RX switch to switch between transmit mode and receive mode operation. The FEM circuitry may include a receive signal path and a transmit signal path. The receive signal path of the FEM circuitry may include a low- noise amplifier (LNA) to amplify received RF signals and provide the amplified received RF signals as an output (e.g., to the RF circuitry 806). The transmit signal path of the FEM circuitry 808 may include a power amplifier (PA) to amplify input RF signals (e.g., provided by RF circuitry 806), and one or more filters to generate RF signals for subsequent transmission (e.g., by one or more of the one or more antennas 810.

[00102] In some embodiments, the UE device 800 may include additional elements such as, for example, memory/storage, display, camera, sensor, and/or input/output (I/O) interface. [00103] In summary, the positioning method 100 of Figure 7 may be implemented in a first example by a computer-readable medium comprising instructions to cause a User Equipment (UE), upon execution of instructions by one or more processors of the UE, to establish, between the UE and an enhanced Node B (eNB), one or more communication links, wherein each link is associated with a pair of beams at the UE and the eNB, receive beamformed positioning reference signals (PRS) over the one or more established communication links, estimate the beam directions of the UE and the eNB for each of the one or more established communication links, obtain a time-of-arrival measurement for the beamformed PRS for each of the one or more established communication links, and communicate the beam directions and time-of-arrival measurements to a location server.

[00104] Further to the first example or any other example discussed herein, in a second example, the beam direction estimation comprises estimation of an orientation of the UE in a global coordinate system.

[00105] Further to the second example or any other example discussed herein, in a third example, the beam direction estimation comprises estimation of an orientation of the eNB in a global coordinate system.

[00106] Further to the second example or any other example discussed herein, in a fourth example, the orientation is obtained using sensors disposed on the UE.

[00107] Further to the fourth example or any other example discussed herein, in a fifth example, the orientation comprises azimuth and elevation orientation information of the beams obtained at a time interval on which the time-of-arrival measurements for location were performed.

[00108] Further to the first, second, or third examples or any other example discussed herein, in a sixth example, the beam direction estimation comprises an estimation of a beam orientation relative to the UE.

[00109] Further to any of the first through sixth examples or any other example discussed herein, in a seventh example, the beam directions comprise azimuth and elevation angles of the beams for each communication link in the global coordinate system. [00110] Further to the first example or any other example discussed herein, in a eighth example, wherein time-of-arrival measurements are selected from a group consisting of observed time difference of arrival (OTDOA), timing (TA) advance, round trip time (RTT), OTDOA plus TA, OTDOA plus RTT, TA plus RTT, and OTDOA plus TA plus RTT.

[00111] Further, the positioning method 100 of Figure 7 may be implemented in a ninth example by an apparatus of a User Equipment (UE), the UE being capable of processing beamformed positioning reference signals (PRS), the apparatus comprising one or more antennas to receive the beamformed PRS over one or more communication links, a beam information calculation unit, to estimate beam information comprising a beam direction of each of the one or more communication links, and transmit the beam information to a location server, a measurement information calculation unit to calculate measurement information comprising time-of-arrival of the beamformed PRS of each of the one or more communication links, and transmit the measurement information to the location server, wherein the UE receives a location of the UE based on the beam information and the measurement information from the location server.

[00112] Further to the ninth example or any other example discussed herein, in a tenth example, the beam information comprises a beam index for each of the one or more communication links.

[00113] Further to the ninth or tenth examples or any other example discussed herein, in an eleventh example, the beam information comprises a beam pointing angle in an azimuth direction.

[00114] Further to any of the ninth through eleventh examples or any other example discussed herein, in a twelfth example, the beam information comprises a beam pointing angle in an elevation direction.

[00115] Further to any of the ninth through twelfth examples or any other example discussed herein, in a thirteenth example, the beam information comprises a relative orientation of the one or more antennas for each of the one or more communication links. [00116] Further to the ninth example or any other example discussed herein, in a fourteenth example, the apparatus of the UE comprises one or more position sensors to calculate beam information.

[00117] Further to the fourteenth example or any other example discussed herein, in a fifteenth example, the position sensors comprise orientation sensors.

[00118] Further to the fourteenth example or any other example discussed herein, in a sixteenth example, the position sensors comprise magnetometers.

[00119] Further to the ninth example or any other example discussed herein, in a seventeenth example, the one or more communication links comprises a line-of sight communication path, a first order reflection communication path, and a second first order reflection communication path.

[00120] Further to the thirteenth example or any other example discussed herein, in an eighteenth example, the one or more communication links comprises a first order reflection communication path, wherein a distance, x, between the UE and an enhanced Node B is calculated using the following formula: x = ^{Sm{r + /3)} d

sin( ) + sin( ?)

wherein beam pointing angles β and γ correspond to the communication link and d is a first order reflection path of the communication link.

[00121] Further, the positioning method 100 of Figure 7 may be implemented in a nineteenth example by a machine-readable storage including machine-readable instructions to realize an apparatus as in any one of the ninth through eighteenth examples or any other example discussed herein.

[00122] Further, the positioning method 100 of Figure 7 may be implemented in a twentieth by a machine-readable storage including machine- readable instructions, when executed, to implement a method or realize an apparatus as claimed in any example discussed herein.

[00123] Further, the positioning method 100 of Figure 7 may be implemented in a twenty-first example by a computer-readable medium comprising instructions to cause an enhanced Node B (eNB), upon execution of instructions by one or more processors of the eNB, to establish, between an User Equipment (UE) and the eNB, one or more communication links, wherein each link is associated with a pair of beams at the UE and the eNB, receive the beamformed positioning reference signals over the one or more established communication links, estimate the beam directions of the UE and the eNB for each of the one or more established communication links, measure Time of Arrival (ToA) of the beamformed positioning reference signals for each of the one or more established communication links, and communicate the beam directions and ToA measurements to a location server.

[00124] Further to the twenty-first example or any other example discussed herein, in a twenty-second example, the instructions cause the eNB to estimate an orientation of the UE that transmitted the beamformed positioning reference signals.

[00125] Further to the twenty-second example or any other example discussed herein, in a twenty-third example, the instructions cause the eNB to estimate the orientation in both azimuth and elevation domains.

[00126] Further to the twenty-third example or any other example discussed herein, in a twenty-fourth example, the instructions cause the eNB to measure ToA using one or more of the following: observed time difference of arrival (OTDOA), timing (TA) advance, and round trip time (RTT).

[00127] While the foregoing examples are illustrative of the principles of the present invention in one or more particular applications, it will be apparent to those of ordinary skill in the art that numerous modifications in form, usage, and details of implementation can be made without the exercise of inventive faculty, and without departing from the principles and concepts of the invention. will appreciate numerous modifications and variations therefrom. It is intended that the appended claims cover all such modifications and variations as fall within the true spirit and scope of the invention.

Claims

I claim:

1 . A computer-readable medium comprising instructions to cause a User Equipment (UE), upon execution of instructions by one or more processors of the UE, to:

establish, between the UE and an enhanced Node B (eNB), one or more communication links, wherein each link is associated with a pair of beams at the UE and the eNB;

receive beamformed positioning reference signals (PRS) over the one or more established communication links;

estimate the beam directions of the UE and the eNB for each of the one or more established communication links;

obtain a time-of-arrival measurement for the beamformed PRS for each of the one or more established communication links; and

communicate the beam directions and time-of-arrival measurements to a location server.

2. The computer-readable medium of claim 1 , wherein the beam direction estimation comprises estimation of an orientation of the UE in a global coordinate system.

3. The computer-readable medium of claim 1 , wherein the beam direction estimation comprises estimation of an orientation of the eNB in a global coordinate system.

4. The computer-readable medium of claim 2, wherein the orientation is obtained using sensors disposed on the UE.

5. The computer-readable medium of claim 4, wherein the orientation comprises azimuth and elevation orientation information of the beams obtained at a time interval on which the time-of-arrival measurements for location were performed.

6. The computer-readable medium of claims 1 , 2, or 3, wherein the beam direction estimation comprises an estimation of a beam orientation relative to the UE.

7. The computer-readable medium of any of claims 1 - 6, wherein the beam directions comprise azimuth and elevation angles of the beams for each communication link in the global coordinate system.

8. The computer-readable medium of claim 1 , wherein time-of-arrival measurements are selected from a group consisting of observed time difference of arrival (OTDOA), timing (TA) advance, round trip time (RTT), OTDOA plus TA, OTDOA plus RTT, TA plus RTT, and OTDOA plus TA plus RTT.

9. An apparatus of a User Equipment (UE), the UE being capable of processing beamformed positioning reference signals (PRS), the apparatus comprising:

one or more antennas to receive the beamformed PRS over one or more communication links;

a beam information calculation unit, to:

estimate beam information comprising a beam direction of each of the one or more communication links; and

transmit the beam information to a location server; a measurement information calculation unit to:

calculate measurement information comprising time-of-arrival of the beamformed PRS of each of the one or more communication links; and

transmit the measurement information to the location server; wherein the UE receives a location of the UE based on the beam information and the measurement information from the location server.

10. The apparatus of the UE of claim 9, wherein the beam information comprises a beam index for each of the one or more communication links.

1 1 . The apparatus of the UE of claims 9 or 10, wherein the beam information comprises a beam pointing angle in an azimuth direction.

12. The apparatus of the UE of any of claims 9 - 1 1 , wherein the beam information comprises a beam pointing angle in an elevation direction.

13. The apparatus of the UE of any of claims 9 - 12, wherein the beam information comprises a relative orientation of the one or more antennas for each of the one or more communication links.

14. The apparatus of the UE of claim 9, further comprising:

one or more position sensors to calculate beam information.

15. The apparatus of the UE of claim 14, wherein the position sensors comprise orientation sensors.

16. The apparatus of the UE of claim 14, wherein the position sensors comprise magnetometers.

17. The apparatus of the UE of claim 9, wherein the one or more communication links comprises:

a line-of sight communication path;

a first order reflection communication path; and

a second first order reflection communication path.

18. The apparatus of the UE of claim 13, wherein the one or more communication links comprises:

a first order reflection communication path;

wherein a distance, x, between the UE and an enhanced Node B is calculated using the following formula: x = ^{Sm{r + /3)} d

sin( ) + sin( ?)

wherein beam pointing angles β and γ correspond to the communication link and d is a first order reflection path of the communication link.

19. A machine-readable storage including machine-readable instructions to realize an apparatus as in any one of claims 9 - 18.

20. A machine-readable storage including machine-readable instructions, when executed, to implement a method or realize an apparatus as claimed in any preceding claim.

21 . A computer-readable medium comprising instructions to cause an enhanced Node B (eNB), upon execution of instructions by one or more processors of the eNB, to:

establish, between an User Equipment (UE) and the eNB, one or more communication links, wherein each link is associated with a pair of beams at the UE and the eNB;

receive the beamformed positioning reference signals over the one or more established communication links;

estimate the beam directions of the UE and the eNB for each of the one or more established communication links;

measure Time of Arrival (ToA) of the beamformed positioning reference signals for each of the one or more established communication links; and

communicate the beam directions and ToA measurements to a location server.

22. The computer-readable medium of claim 21 , further comprising instructions to cause the eNB to:

estimate an orientation of the UE that transmitted the beamformed positioning reference signals.

23. The computer-readable medium of claim 22, further comprising instructions to cause the eNB to:

estimate the orientation in both azimuth and elevation domains.

24. The computer-readable medium of claim 22, further comprising instructions to cause the eNB to:

measure ToA using one or more of the following:

observed time difference of arrival (OTDOA);

timing (TA) advance; and

round trip time (RTT).