Differential Angle of Arrival (AOA) for Low-Power Mobile Device Positioning

Abstract

Techniques are disclosed for enabling low power positioning of a first mobile device using differential angle of arrival (AoA). A differential AoA between a first AoA of a first wireless reference signal at a second mobile device and a second AoA of a second wireless reference signal at the second mobile device is obtained, the first wireless reference signal being transmitted by a wireless network node, and the second wireless reference signal being transmitted by the first mobile device. A location of the first mobile device is determined based at least in part on the differential AoA. The location of the first mobile device is then provided.

Description

[Technical field]

[0001] Related Applications

[0001] This application claims the benefit of Greek Application No. 20210100145, entitled "DIFFERENTIAL ANGLE OF ARRIVAL (AOA) FOR LOW POWER MOBILE DEVICE POSITIONING," filed on March 10, 2021, which is assigned to the assignee of this application and is incorporated by reference in its entirety herein.

[0002] The present invention relates generally to the field of wireless communications, and more particularly to determining the location (or position) of user equipment (UE) using radio frequency (RF) signals. [Background technology]

[0003]

[0003] In data communication networks, various positioning techniques may be used to determine the position of a mobile device (referred to herein as user equipment or UE). Some of these positioning techniques may involve the use of an "anchor" UE to help determine the location of a "target" UE, where the anchor UE may take measurements of RF signals to determine distance and / or angle information of the target UE. One way in which the anchor UE may obtain angle information is through angle of arrival (AoA) measurements, but making accurate AoA measurements may be difficult if the orientation of the anchor UE is unknown. Summary of the Invention

[0004] An example method for enabling low power positioning of a first mobile device using differential angle of arrival (AoA) according to the present disclosure comprises obtaining a differential AoA between a first AoA of a first wireless reference signal at a second mobile device and a second AoA of a second wireless reference signal at the second mobile device, where the first wireless reference signal is transmitted by a first wireless network node (e.g., a transmit / receive point (TRP) or a network-connected UE) and the second wireless reference signal is transmitted by the first mobile device. The method also comprises determining a location of the first mobile device based at least in part on the differential AoA. The method also comprises providing a location of the first mobile device.

[0005]

[0005] An exemplary device enabling low power positioning of a first mobile device using differential angle of arrival (AoA) according to the present disclosure comprises a transceiver, a memory, and one or more processing units communicatively coupled to the transceiver and the memory. The one or more processing units are configured to obtain, via the transceiver, a differential AoA between a first AoA of a first wireless reference signal at a second mobile device and a second AoA of a second wireless reference signal at the second mobile device, the first wireless reference signal being transmitted by a first wireless network node and the second wireless reference signal being transmitted by the first mobile device. The one or more processing units are also configured to determine a location of the first mobile device based at least in part on the differential AoA. The one or more processing units are also configured to provide a location of the first mobile device.

[0006] Another exemplary device for enabling low power positioning of a first mobile device using differential angle of arrival (AoA) according to the present disclosure comprises means for obtaining a differential AoA between a first AoA of a first wireless reference signal at a second mobile device and a second AoA of a second wireless reference signal at the second mobile device, the first wireless reference signal being transmitted by a first wireless network node and the second wireless reference signal being transmitted by the first mobile device. The device also comprises means for determining a location of the first mobile device based at least in part on the differential AoA. The device also comprises means for providing a location of the first mobile device.

[0007] An exemplary non-transitory computer-readable medium according to the present disclosure stores instructions for enabling low power positioning of a first mobile device using differential angle of arrival (AoA). The instructions include code for obtaining a differential AoA between a first AoA of a first wireless reference signal at a second mobile device and a second AoA of a second wireless reference signal at the second mobile device, the first wireless reference signal being transmitted by a first wireless network node and the second wireless reference signal being transmitted by the first mobile device. The instructions also include code for determining a location of the first mobile device based at least in part on the differential AoA. The instructions also include code for providing a location of the first mobile device. [Brief description of the drawings]

[0008] [Figure 1] 1 is a diagram of a positioning system, according to one embodiment. [Diagram 2]

[0009] FIG. 5 is a diagram of a fifth generation (5G) new radio (NR) positioning system illustrating one embodiment of a positioning system implemented within a 5G NR communication system (e.g., the positioning system of FIG. 1). [Diagram 3]

[0010] Diagram showing beamforming in a 5G NR positioning system. [Figure 4]

[0011] 1 is a simplified diagram illustrating how network-based location determination of a target user equipment (UE) may be performed, according to one embodiment. [Figure 5A]

[0012] FIG. 11 is a diagram of a wireless network node, a target UE, and an anchor UE provided to illustrate how beams may be used differently in different embodiments and / or situations depending on the desired functionality. [Figure 5B] FIG. 11 is a diagram of a wireless network node, a target UE, and an anchor UE provided to illustrate how beams may be used differently in different embodiments and / or situations depending on the desired functionality. [Figure 6]

[0013] 2 illustrates a configuration for resolving ambiguity in the location determination of a target UE, according to one embodiment. [Figure 7]

[0014] 1 is a simplified diagram illustrating how multiple anchor UEs may be used to resolve ambiguity in the location of a target UE, according to one embodiment. [Figure 8]

[0015] 4 is a call flow diagram of a process for performing location determination of a target UE, according to some embodiments. [Figure 9] 4 is a call flow diagram of a process for performing location determination of a target UE, according to some embodiments. [Figure 10]

[0016] 4 is a flow diagram of a method for enabling low power positioning of a first mobile device using differential AoA, according to one embodiment. [Figure 11]

[0017] 1 is a block diagram of one embodiment of a mobile device that can be utilized in the embodiments described herein. [Figure 12]

[0018] FIG. 1 is a block diagram of one embodiment of a computer system that may be utilized in the embodiments described herein. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009]

[0019] The same reference numbers in various figures refer to the same elements according to some exemplary implementations. In addition, multiple instances of an element may be indicated by a first number of the element followed by a letter or a hyphen and a second number. For example, multiple instances of element 110 may be indicated as 110-1, 110-2, 110-3, etc., or as 110a, 110b, 110c, etc. When referring to such an element using only the first number, it should be understood as any instance of the element (e.g., element 110 in the previous example would refer to elements 110-1, 110-2, and 110-3, or elements 110a, 110b, and 110c).

[0010]

[0020] Several illustrative embodiments will now be described with reference to the accompanying drawings, which form a part of this specification. Some embodiments in which one or more aspects of the present disclosure may be implemented may be implemented as described below, although other embodiments may be used and various modifications may be made without departing from the scope of the present disclosure.

[0011]

[0021] As used herein, an "RF signal" or "reference signal" comprises an electromagnetic wave that transports information through space between a transmitter (or transmitting device) and a receiver (or receiving device). As used herein, a transmitter may transmit a single RF / reference signal or multiple RF / reference signals to a receiver. However, a receiver (or different receivers) may receive multiple RF / reference signals corresponding to each transmitted RF signal due to the propagation characteristics of RF signals through a multipath channel. The same transmitted RF signal on different paths between a transmitter and a receiver may be referred to as a "multipath RF signal."

[0012]

[0022] 1 is a simplified illustration of a positioning system 100 according to one embodiment, in which a UE 105, a location server 160, and / or other components of the positioning system 100 can use techniques provided herein for determining a differential angle of arrival (AoA) for low power mobile device positioning of the UE 105. The techniques described herein may be implemented by one or more components of the positioning system 100. The positioning system 100 can include a UE 105, one or more satellites 110 (also referred to as space vehicles (SVs)) for a global navigation satellite system (GNSS), such as Global Positioning System (GPS), GLONASS, Galileo or Beidou, a base station 120, an access point (AP) 130, a location server 160, a network 170, and an external client 180. Generally speaking, the positioning system 100 can estimate the location of the UE 105 based on RF signals received by and / or sent from the UE 105 and known locations of other components (e.g., GNSS satellites 110, base stations 120, APs 130) that are transmitting and / or receiving the RF signals. Further details regarding specific location estimation techniques are discussed in more detail with respect to FIG.

[0013]

[0023] It should be noted that FIG. 1 provides only a generalized view of the various components, any or all of which may be utilized as appropriate, and each of which may be replicated as necessary. In particular, while only one UE 105 is shown, it will be understood that many UEs (e.g., hundreds, thousands, millions, etc.) may utilize the positioning system 100. Similarly, the positioning system 100 may include a greater or lesser number of base stations 120 and / or APs 130 than those shown in FIG. 1. The illustrated connections connecting the various components in the positioning system 100 comprise data and signaling connections that may include additional (intermediate) components, direct or indirect physical and / or wireless connections, and / or additional networks. Furthermore, components may be rearranged, combined, separated, substituted, and / or omitted depending on the desired functionality. In some embodiments, for example, the external client 180 may be directly connected to the location server 160. Those skilled in the art will recognize many modifications to the illustrated components.

[0014]

[0024] Depending on the desired functionality, network 170 may comprise any of a variety of wireless and / or wireline networks. Network 170 may comprise any combination of, for example, public and / or private networks, local and / or wide area networks, and the like. Additionally, network 170 may utilize one or more wired and / or wireless communication technologies. In some embodiments, network 170 may comprise, for example, a cellular or other mobile network, a wireless local area network (WLAN), a wireless wide area network (WWAN), and / or the Internet. Examples of network 170 include a Long Term Evolution (LTE) wireless network, a fifth generation (5G) wireless network (also referred to as a New Radio (NR) wireless network or a 5G NR wireless network), a Wi-Fi WLAN, and the Internet. LTE, 5G, and NR are wireless technologies defined or being defined by the 3rd Generation Partnership Project (3GPP). Network 170 may also include two or more networks and / or two or more types of networks.

[0015]

[0025] The base station 120 and the access point (AP) 130 are communicatively coupled to the network 170. In some embodiments, the base station 120 may be owned, maintained, and / or operated by a cellular network provider and may employ any of a variety of wireless technologies, as described herein below. Depending on the technology of the network 170, the base station 120 may comprise a Node B, an evolved Node B (eNode B or eNB), a base transceiver station (BTS), a radio base station (RBS), an NR Node B (gNB), a next generation eNB (ng-eNB), etc. A base station 120 that is a gNB or ng-eNB may be part of a next generation radio access network (NG-RAN) that may connect to a 5G core network (5GC) if the network 170 is a 5G network. The AP 130 may comprise, for example, a Wi-Fi AP or a Bluetooth AP. Thus, the UE 105 may send and receive information to and from a network-connected device, such as the location server 160, by accessing the network 170 via the base station 120 using the first communication link 133. Additionally or alternatively, the AP 130 may also be communicatively coupled to the network 170 so that the UE 105 may use the second communications link 135 to communicate with network- and Internet-connected devices, including a location server 160 .

[0016]

[0026] The term "base station" as used herein may generally refer to a single physical transmission point or multiple co-located physical transmission points that may be located at a base station 120. A transmit / receive point (TRP) (also known as a transmit / receive point) corresponds to this type of transmission point, and the term "TRP" may be used interchangeably with the terms "gNB", "ng-eNB", and "base station" herein. In some cases, a base station 120 may comprise multiple TRPs, e.g., each TRP associated with a different antenna or different antenna array for the base station 120. A physical transmission point may comprise an array of antennas at the base station 120 (e.g., as in a multiple-input multiple-output (MIMO) system and / or when the base station employs beamforming). The term "base station" may further refer to multiple non-co-located physical transmission points, which may be a distributed antenna system (DAS) (a network of spatially separated antennas connected to a common source via a transport medium) or a remote radio head (RRH) (a remote base station connected to a serving base station).

[0017]

[0027] The term "cell" as used herein may generally refer to a logical communication entity used for communication with base station 120 and may be associated with an identifier (e.g., physical cell identifier (PCID), virtual cell identifier (VCID)) to distinguish neighboring cells operating over the same or different carriers. In some examples, a carrier may support multiple cells, and different cells may be configured according to different protocol types (e.g., machine type communications (MTC), narrowband Internet of Things (NB-IoT), enhanced mobile broadband (eMBB), etc.) that may provide access to different types of devices. In some cases, the term "cell" may refer to a portion (e.g., a sector) of a geographic coverage area over which a logical entity operates.

[0018]

[0028] The location server 160 may comprise a server and / or other computing devices configured to determine an estimated location of the UE 105 and / or provide data (e.g., “assistance data”) to the UE 105 for facilitating location measurements and / or location determination by the UE 105. According to some embodiments, the location server 160 may comprise a Home SUPL Location Platform (H-SLP) that may support a Secure User Plane Location (SUPL) User Plane (UP) location solution defined by the Open Mobile Alliance (OMA) and may support location services for the UE 105 based on subscription information of the UE 105 stored in the location server 160. In some embodiments, the location server 160 may comprise a Discovery SLP (D-SLP) or an Emergency SLP (E-SLP). The location server 160 may also comprise an Enhanced Serving Mobile Location Center (E-SMLC) that supports the location of the UE 105 using a Control Plane (CP) location solution for LTE radio access by the UE 105. The location server 160 may further comprise a location management function (LMF) that supports the location of the UE 105 using a control plane (CP) location solution for NR or LTE radio access by the UE 105.

[0019]

[0029] In a CP location solution, signaling for controlling and managing the location of the UE 105 may be exchanged between elements of the network 170 and with the UE 105 using existing network interfaces and protocols, and as signaling from the perspective of the network 170. In a UP location solution, signaling for controlling and managing the location of the UE 105 may be exchanged between the location server 160 and the UE 105 as data from the perspective of the network 170 (e.g., data transported using Internet Protocol (IP) and / or Transmission Control Protocol (TCP)).

[0020]

[0030] As mentioned above (and discussed in more detail below), the estimated location of the UE 105 may be based on measurements of RF signals sent from and / or received by the UE 105. In particular, these measurements may provide information regarding the relative distance and / or angle of the UE 105 from one or more components (e.g., GNSS satellites 110, AP 130, base station 120) in the positioning system 100. The estimated location of the UE 105 may be estimated geometrically (e.g., using multi-angulation and / or multi-lateration) based on the distance and / or angle measurements along with the known positions of the one or more components.

[0021]

[0031] Terrestrial components such as APs 130 and base stations 120 may be fixed, although embodiments are not so limited. Mobile components may be used. For example, in some embodiments, the location of the UE 105 may be estimated based at least in part on measurements of RF signals 140 communicated between the UE 105 and one or more other UEs 145, which may be mobile or fixed. When one or more other UEs 145 are used in position determination of a particular UE 105, the UE 105 whose position is to be determined may be referred to as a "target UE" and each of the one or more other UEs 145 used may be referred to as an "anchor UE." For purposes of position determination of a target UE, the respective positions of the one or more anchor UEs may be known and / or may be determined together with the target UE. Direct communication between the one or more other UEs 145 and the UE 105 may comprise sidelink and / or similar device-to-device (D2D) communication techniques. Sidelink, as defined by 3GPP, is a form of D2D communication under cellular-based LTE and NR standards.

[0022]

[0032] The estimated location of the UE 105 may be used in various applications, such as, for example, to assist a user of the UE 105 in direction finding or navigation, or to assist another user (e.g., associated with the external client 180) in locating the UE 105. "Location" may also be referred to herein as a "location estimate," "estimated location," "location," "position," "position estimate," "position fix," "estimated position," "location fix," or "fix." The process of determining a location may be referred to as "positioning," "position determination," "location determination," or the like. The location of the UE 105 may comprise the absolute location of the UE 105 (e.g., latitude and longitude and possibly an altitude) or the relative location of the UE 105 (e.g., a location expressed as a distance north or south, east or west, and possibly up or down from some other location, such as some other known fixed location, or the location of the UE 105 at some known prior time). A location may be specified as a geodetic location with coordinates that may be absolute (e.g., latitude, longitude and possibly altitude), relative (e.g., relative to some known absolute location), or local (e.g., X, Y and possibly Z coordinates according to a coordinate system defined for a local area such as a factory, warehouse, university campus, shopping mall, sports stadium or convention center). A location may instead be a civic location, in which case it may comprise one or more of a street address (including, e.g., a country, state, county, city, road and / or street name or label, and / or road or street number), and / or a label or name of a place, building, part of a building, floor of a building, and / or room within a building, etc.The location may further include an uncertainty or error indication, such as the horizontal and possibly vertical distance by which the location is expected to be incorrect, or an indication of an area or volume (e.g., a circle or ellipse) within which the UE 105 is expected to be located with some confidence level (e.g., 95% confidence).

[0023]

[0033] The external client 180 may be a web server or remote application that may have some association with the UE 105 (e.g., that may be accessed by a user of the UE 105), or may be a server, application, or computer system that provides location services to some other user or users that may include obtaining and providing the location of the UE 105 (e.g., to enable services such as a friend or relative finder, asset tracking, or child or pet location). Additionally or alternatively, the external client 180 may obtain and provide the location of the UE 105 to an emergency service provider, a government agency, or the like.

[0024]

[0034] As previously mentioned, the exemplary positioning system 100 may be implemented using a wireless communication network, such as an LTE-based or 5G NR-based network. FIG. 2 shows a diagram of a 5G NR positioning system 200 illustrating one embodiment of a positioning system (e.g., the positioning system 100) implementing 5G NR. The 5G NR positioning system 200 may be configured to determine the location of the UE 105 using access nodes 210, 214, 216 (which may correspond to the base stations 120 and access points 130 of FIG. 1 ) and (optionally) an LMF 220 (which may correspond to the location server 160) to implement one or more positioning methods. Here, the 5G NR positioning system 200 comprises the UE 105 and components of a 5G NR network, including a Next Generation (NG) Radio Access Network (RAN) (NG-RAN) 235 and a 5G Core Network (5G CN) 240. The 5G network may be referred to as an NR network, the NG-RAN 235 may be referred to as a 5G RAN or NR RAN, and the 5G CN 240 may be referred to as an NG core network. The 5G NR positioning system 200 may further utilize information from GNSS satellites 110 from a GNSS system such as the Global Positioning System (GPS) or similar systems (e.g., GLONASS, Galileo, Beidou, IRNSS). Additional components of the 5G NR positioning system 200 are described below. The 5G NR positioning system 200 may include additional or alternative components.

[0025]

[0035] It should be noted that FIG. 2 provides only a generalized view of the various components, any or all of which may be utilized as appropriate, and each of which may be duplicated or omitted as necessary. In particular, while only one UE 105 is shown, it will be understood that many UEs (e.g., hundreds, thousands, millions, etc.) may utilize the 5G NR positioning system 200. Similarly, the 5G NR positioning system 200 may include a greater (or lesser) number of GNSS satellites 110, gNBs 210, ng-eNBs 214, wireless local area networks (WLANs) 216, access and mobility management functions (AMFs) 215, external clients 230, and / or other components. The illustrated connections connecting the various components in the 5G NR positioning system 200 include data and signaling connections, which may include additional (intermediate) components, direct or indirect physical and / or wireless connections, and / or additional networks. Additionally, components may be rearranged, combined, separated, substituted, and / or omitted depending on the desired functionality.

[0026]

[0036] The UE 105 may comprise and / or 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 by some other name. Moreover, the UE 105 may correspond to a cell phone, a smartphone, a laptop, a tablet, a personal digital assistant (PDA), a tracking device, a navigation device, an Internet of Things (IoT) device, or some other portable or mobile device. Typically, but not necessarily, the UE 105 may support wireless communications using one or more radio access technologies (RATs), such as using GSM, Code Division Multiple Access (CDMA), Wideband CDMA (W-CDMA), LTE, High Rate Packet Data (HRPD), IEEE 802.11 Wi-Fi, Bluetooth, Worldwide Interoperability for Microwave Access (WiMAX), 5G NR (e.g., using NG-RAN 235 and 5G CN 240), and the like. The UE 105 may also support wireless communications using a WLAN 216, which may connect to other networks, such as the Internet (as one or more RATs and as described above with respect to FIG. 1). Use of one or more of these RATs may enable the UE 105 to communicate with and / or receive location information regarding the UE 105 (e.g., via elements of the 5G CN 240 not shown in FIG. 2 or possibly via a Gateway Mobile Location Center (GMLC) 225) external clients 230. The external clients 230 of FIG. 2 may correspond to the external clients 180 of FIG. 1 implemented in or communicatively coupled to a 5G NR network.

[0027]

[0037] The UE 105 may include a single entity or 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 a separate wireline or wireless modem. An estimate of the location of the UE 105 may be referred to as a location, location estimate, location fix, fix, position, position estimate, or position fix, and may be geodetic and thus provide location coordinates (e.g., latitude and longitude) of the UE 105 that may or may not include an altitude component (e.g., height above sea level, height above or below ground level, floor level or basement level). Alternatively, the location of the UE 105 may be expressed as a civic location (e.g., as a postal address or a designation of some point or small area in a building such as a particular room or floor). The location of the UE 105 may also be expressed as an area or volume (defined geodesically or in urban terms) within which the UE 105 is expected to be located with some probability or confidence level (e.g., 67%, 95%, etc.). The location of the UE 105 may further be a relative location with distance and direction or relative X, Y (and Z) coordinates defined relative to some origin in a known location, which may be defined, for example, geodesically, in urban terms, or by reference to a point, area, or volume shown on a map, floor plan, or building plan. In the description contained herein, use of the term location may include any of these variations unless otherwise specified. When calculating the location of a UE, it is customary to solve for local X, Y, and possibly Z coordinates and then convert the local coordinates to absolute coordinates if necessary (e.g., for latitude, longitude, and altitude below or above mean sea level).

[0028]

[0038] The base stations in the NG-RAN 235 shown in FIG. 2 may correspond to the base stations 120 in FIG. 1 and may include NR NodeBs (gNBs) 210-1 and 210-2 (collectively and generically referred to herein as gNBs 210). Pairs of gNBs 210 in the NG-RAN 235 may be connected to one another (e.g., directly as shown in FIG. 2 or indirectly via other gNBs 210). Access to the 5G network is provided to the UE 105 via wireless communications between the UE 105 and one or more of the gNBs 210, which may provide wireless communications access to the 5G CN 240 for the UE 105 using 5G NR. 5G NR radio access may also be referred to as NR radio access or 5G radio access. In FIG. 2, it is assumed that the serving gNB for UE 105 is gNB 210-1, but other gNBs (e.g., gNB 210-2) may act as serving gNBs if UE 105 moves to another location or as secondary gNBs to provide additional throughput and bandwidth to UE 105.

[0029]

[0039] The base stations in the NG-RAN 235 shown in FIG. 2 may also or instead include a next generation evolved node B 214, also referred to as an ng-eNB. The ng-eNB 214 may be connected to one or more gNBs 210 in the NG-RAN 235, e.g., directly or indirectly via other gNBs 210 and / or other ng-eNBs. The ng-eNB 214 may provide LTE wireless access and / or evolved LTE (eLTE) wireless access to the UE 105. Some gNBs 210 (e.g., gNB 210-2) and / or ng-eNBs 214 in FIG. 2 may be configured to function as positioning-only beacons that may transmit signals (e.g., positioning reference signals (PRS)) and / or broadcast assistance data to assist in positioning the UE 105, but may not receive signals from the UE 105 or other UEs. It should be noted that while only one ng-eNB 214 is shown in FIG. 2, some embodiments may include multiple ng-eNBs 214. The base stations 210, 214 may communicate directly with each other via an Xn communication interface. Additionally or alternatively, the base stations 210, 214 may communicate directly or indirectly with other components of the 5G NR positioning system 200, such as the LMF 220 and the AMF 215.

[0030]

[0040] The 5G NR positioning system 200 may also include one or more WLANs 216 that may connect to a non-3GPP interworking function (N3IWF) 250 in the 5G CN 240 (e.g., in case of an untrusted WLAN 216). For example, the WLAN 216 may support IEEE 802.11 Wi-Fi access for the UE 105 and may comprise one or more Wi-Fi APs (e.g., AP 130 of FIG. 1). Here, the N3IWF 250 may connect to other elements in the 5G CN 240, such as the AMF 215. In some embodiments, the WLAN 216 may support another RAT, such as Bluetooth. The N3IWF 250 may provide support for secure access by the UE 105 to other elements in the 5G CN 240 and / or support interworking of one or more protocols used by the WLAN 216 and the UE 105 to one or more protocols used by other elements of the 5G CN 240, such as the AMF 215. For example, the N3IWF 250 may support IPSec tunnel establishment with the UE 105, termination of IKEv2 / IPSec protocols with the UE 105, termination of the N2 and N3 interfaces to the 5G CN 240 for the control plane and user plane, respectively, relaying uplink (UL) and downlink (DL) control plane non-access stratum (NAS) signaling between the UE 105 and the AMF 215 via the N1 interface. In some other embodiments, the WLAN 216 may directly connect to an element in the 5G CN 240 (e.g., the AMF 215 as shown by the dashed line in FIG. 2) without going through the N3IWF 250. For example, a direct connection of the WLAN 216 to the 5G CN 240 may be made if the WLAN 216 is a trusted WLAN for the 5G CN 240 and may be enabled using a trusted WLAN interworking function (TWIF) (not shown in FIG. 2), which may be an element within the WLAN 216. It should be noted that although only one WLAN 216 is shown in FIG. 2, some embodiments may include multiple WLANs 216.

[0031]

[0041] An access node may comprise any of a variety of network entities that enable communication between the UE 105 and the AMF 215. This may include a gNB 210, an ng-eNB 214, a WLAN 216, and / or other types of cellular base stations. However, an access node providing the functionality described herein may additionally or alternatively include entities that enable communication to any of a variety of RATs not shown in FIG. 2, which may include non-cellular technologies. Thus, the term "access node" as used in the embodiments described herein below may include, but is not necessarily limited to, a gNB 210, an ng-eNB 214, or a WLAN 216.

[0032]

[0042] In some embodiments, an access node such as the gNB 210, ng-eNB 214, or WLAN 216 (alone or in combination with other components of the 5G NR positioning system 200) may be configured to obtain location measurements of uplink (UL) signals received from the UE 105, and / or obtain downlink (DL) location measurements from the UE 105 for DL ​​signals received by the UE 105 from one or more ANs, in response to receiving a request for location information from the LMF 220. As mentioned, although FIG. 2 illustrates access nodes 210, 214, and 216 configured to communicate according to 5G NR, LTE, and Wi-Fi communication protocols, respectively, access nodes configured to communicate according to other communication protocols may be used, such as, for example, a Node B using a WCDMA protocol for a Universal Mobile Telecommunications Service (UMTS) Terrestrial Radio Access Network (UTRAN), an eNB using an LTE protocol for an Evolved UTRAN (E-UTRAN), or Bluetooth Beacons using a Bluetooth protocol for a WLAN. For example, in a 4G Evolved Packet System (EPS) providing LTE wireless access to the UE 105, the RAN may comprise an E-UTRAN, which may comprise base stations with eNBs supporting LTE wireless access. The core network of the EPS may comprise an Evolved Packet Core (EPC). The EPS may then comprise an E-UTRAN+EPC, where the E-UTRAN corresponds to the NG-RAN 235 and the EPC corresponds to the 5GCN 240 of FIG. 2. The methods and techniques described herein for obtaining the urban location of the UE 105 may be applicable to such other networks.

[0033]

[0043] The gNB 210 and ng-eNB 214 may communicate with an AMF 215, which communicates with the LMF 220 for positioning functions. The AMF 215 may support mobility of the UE 105, including cell changes and handovers of the UE 105 from a first RAT access node 210, 214, or 216 to a second RAT access node 210, 214, or 216. The AMF 215 may also be responsible for supporting signaling connections to the UE 105 and possibly data and voice bearers for the UE 105. The LMF 220 may support positioning of the UE 105 using a CP location solution when the UE 105 accesses the NG-RAN 235 or the WLAN 216, and may support position procedures and methods including UE-assisted / UE-based and / or network-based procedures / methods, such as Aided GNSS (A-GNSS), Observed Time Difference of Arrival (OTDOA) (sometimes referred to as DL Time Difference of Arrival (DL-TDOA) in NR), Real Time Kinematic (RTK), Precise Point Positioning (PPP), Differential GNSS (DGNSS), Enhanced Cell ID (ECID), Angle of Arrival (AOA), Angle of Departure (AOD), WLAN positioning, Round Trip Signal Propagation Delay (RTT), Multi-cell RTT, and / or other positioning procedures and methods. The LMF 220 may also process location service requests for the UE 105, for example, received from the AMF 215 or the GMLC 225. The LMF 220 may be connected to the AMF 215 and / or the GMLC 225. In some embodiments, a network such as 5GCN240 may additionally or alternatively implement other types of location support modules, such as an Evolved Serving Mobile Location Center (E-SMLC) or a SUPL Location Platform (SLP).It should be noted that in some embodiments, at least a portion of the positioning functions (including determining the location of the UE 105) may be performed in the UE 105 (e.g., by measuring downlink PRS (DL-PRS) signals transmitted by wireless nodes such as the gNB 210, the ng-eNB 214 and / or the WLAN 216 and / or using assistance data provided to the UE 105 by, for example, the LMF 220).

[0034]

[0044] The gateway mobile location center (GMLC) 225 may support location requests for the UE 105 received from the external client 230 and may forward such location requests to the AMF 215 for forwarding by the AMF 215 to the LMF 220. A location response from the LMF 220 (e.g., including a location estimate for the UE 105) may similarly be returned to the GMLC 225 directly or via the AMF 215, which may then return a location response (e.g., including the location estimate) to the external client 230.

[0035]

[0045] A network exposure function (NEF) 245 may be included in the 5GCN 240. The NEF 245 may support secure exposure of capabilities and events related to the 5GCN 240 and the UE 105 to the external client 230, which may then be referred to as an access function (AF), and may enable secure provision of information from the external client 230 to the 5GCN 240. The NEF 245 may be connected to the AMF 215 and / or the GMLC 225 for the purposes of obtaining the location (e.g., a civic location) of the UE 105 and providing the location to the external client 230.

[0036]

[0046] As further shown in FIG. 2, the LMF 220 may communicate with the gNB 210 and / or the ng-eNB 214 using NR Positioning Protocol A (NRPPa) defined in 3GPP Technical Specification (TS) 38.455. NRPPa messages may be transferred between the gNB 210 and the LMF 220 and / or between the ng-eNB 214 and the LMF 220 via the AMF 215. As further shown in FIG. 2, the LMF 220 and the UE 105 may communicate using the LTE Positioning Protocol (LPP) defined in 3GPP TS 37.355. Here, LPP messages may be transferred between the UE 105 and the LMF 220 via the AMF 215 and the serving gNB 210-1 or the serving ng-eNB 214 for the UE 105. For example, LPP messages may be transferred between the LMF 220 and the AMF 215 using service-based operation messages (e.g., based on HyperText Transfer Protocol (HTTP)) and between the AMF 215 and the UE 105 using 5G NAS protocols. The LPP protocol may be used to support positioning of the UE 105 using UE-assisted and / or UE-based position methods such as A-GNSS, RTK, OTDOA, multi-cell RTT, AOD, and / or ECID. The NRPPa protocol may be used to support positioning of the UE 105 using network-based position methods such as ECID, AOA, Uplink TDOA (UL-TDOA), and / or may be used by the LMF 220 to obtain location related information from the gNB 210 and / or ng-eNB 214, such as parameters defining DL-PRS transmissions from the gNB 210 and / or ng-eNB 214.

[0037]

[0047] In the case of UE 105 access to WLAN 216, LMF 220 may use NRPPa and / or LPP to obtain the location of UE 105 in a similar manner as just described for UE 105 access to gNB 210 or ng-eNB 214. Thus, NRPPa messages may be forwarded between WLAN 216 and LMF 220 via AMF 215 and N3IWF 250 to support network-based positioning of UE 105 and / or forwarding of other location information from WLAN 216 to LMF 220. Alternatively, NRPPa messages may be forwarded between N3IWF 250 and LMF 220 via AMF 215 to support network-based positioning of UE 105 based on location related information and / or location measurements known to or accessible to N3IWF 250 and forwarded from N3IWF 250 to LMF 220 using NRPPa. Similarly, LPP and / or LPP messages may be transferred between the UE 105 and the LMF 220 via the AMF 215, the N3IWF 250, and the serving WLAN 216 for the UE 105 to support UE-assisted or UE-based positioning of the UE 105 by the LMF 220.

[0038]

[0048] In a 5G NR positioning system 200, positioning methods may be categorized as being "UE-assisted" or "UE-based". This may depend on where the request to determine the position of the UE 105 originates. For example, if the request originates at the UE (e.g., from an application, or "app," executed by the UE), the positioning method may be categorized as being UE-based. On the other hand, if the request originates from an external client or the AF 230, the LMF 220, or other devices or services in the 5G network, the positioning method may be categorized as being UE-assisted (or "network-based").

[0039]

[0049] With the UE-assisted location method, the UE 105 may obtain location measurements and send the measurements to a location server (e.g., the LMF 220) for calculation of a location estimate of the UE 105. In the RAT-dependent location method, the location measurements may include one or more of the following: received signal strength indicator (RSSI), round-trip signal propagation time (RTT), reference signal received power (RSRP), reference signal received quality (RSRQ), reference signal time difference (RSTD), time of arrival (ToA), AoA, received time-transmitted time difference (Rx-Tx), differential AoA, AoD, or timing advance (TA) of one or more access points for the gNB 210, the ng-eNB 214, and / or the WLAN 216. Additionally or alternatively, if the locations of other UEs are known, similar measurements of sidelink signals transmitted by these other UEs may be made, which may serve as anchor points for the positioning of the UE 105. The location measurements may also or instead include measurements of RAT-independent positioning methods, such as GNSS (e.g., GNSS pseudorange, GNSS code phase, and / or GNSS carrier phase of GNSS satellites 110), WLAN, etc.

[0040]

[0050] Using the UE-based location method, the UE 105 may obtain location measurements (which may, for example, be the same as or similar to the location measurements of the UE-assisted location method) and may further calculate the location of the UE 105 (e.g., with the help of assistance data received from a location server such as the LMF 220, an SLP, or broadcast by the gNB 210, the ng-eNB 214, or the WLAN 216).

[0041]

[0051] Using network-based location methods, one or more base stations (e.g., gNB210 and / or ng-eNB214), one or more APs (e.g., in WLAN216), or N3IWF250 may obtain location measurements (e.g., RSSI, RTT, RSRP, RSRQ, AoA, or ToA measurements) of signals transmitted by UE105 and / or receive measurements obtained by UE105 or, in the case of N3IWF250, by APs in WLAN216 and send the measurements to a location server (e.g., LMF220) for calculation of a location estimate for UE105.

[0042]

[0052] The positioning of the UE 105 may also be categorized as UL, DL, or DL-UL based depending on the type of signal used for positioning. For example, if the positioning is based only on signals received at the UE 105 (e.g., from a base station or other UE), the positioning may be categorized as DL based. On the other hand, if the positioning is based only on signals transmitted by the UE 105 (e.g., may be received by a base station or other UE), the positioning may be categorized as UL based. Positioning that is DL-UL based includes positioning that is based on signals both transmitted and received by the UE 105, such as RTT-based positioning.

[0043]

[0053] Depending on the type of positioning (e.g., UL, DL, or DL-UL based), the type of reference signal used may vary. For example, in DL-based positioning, these signals may comprise PRS (e.g., DL-PRS transmitted by the base station or SL-PRS transmitted by other UEs) that may be used for OTDOA, AOD, and RTT measurements. Other reference signals that may be used for positioning (UL, DL, or DL-UL) may include sounding reference signals (SRS), channel state information reference signals (CSI-RS), synchronization signals (e.g., synchronization signal block (SSB) synchronization signal (SS)), physical uplink control channel (PUCCH), physical uplink shared channel (PUSCH), physical sidelink shared channel (PSSCH), demodulation reference signal (DMRS), etc. Moreover, reference signals may be transmitted in the Tx beam and / or received in the Rx beam (e.g., using beamforming techniques), which may affect angle measurements such as AOD and / or AOA.

[0044]

[0054] 3 is a diagram illustrating a simplified environment 300 that includes two base stations 120-1 and 120-2 (which may correspond to base stations 120 of FIG. 1 and / or gNB 210 and / or ng-eNB 214 of FIG. 2) that generate directional beams for transmitting RF reference signals, and a UE 105. Each of the directional beams is rotated, for example, through 120 degrees or 360 degrees for each beam sweep, which may be repeated periodically. Each directional beam may include an RF reference signal (e.g., PRS resource), with base station 120-1 generating a set of RF reference signals including Tx beams 305-a, 305-b, 305-c, 305-d, 305-e, 305-f, 305-g, and 305-h, and base station 120-2 generating a set of RF reference signals including Tx beams 309-a, 309-b, 309-c, 309-d, 309-e, 309-f, 309-g, and 309-h. Because UE 105 may also include an antenna array, UE 105 may receive RF reference signals transmitted by base stations 120-1 and 120-2 using beamforming to form respective receive beams (Rx beams) 311-a and 311-b. Using such a scheme of beamforming (by base station 120 and optionally UE 105), communications may be made more efficient. They may also be used for other purposes, including taking AoD and AoA measurements for position determination.

[0045]

[0055] Network-based positioning of a UE may often require the UE to communicate with multiple base stations. In RTT-based positioning, for example, RTT measurements may involve transmitting and receiving wireless reference signals to and from multiple base stations, and also reporting Rx-Tx time difference measurements to the serving base station. For some types of UEs, such as mobile phones, the power requirements of RTT-based positioning may not be an issue. However, for "lite" UEs, which typically have a much tighter power budget, these types of communications may be problematic.

[0046]

[0056] As used herein, the term "lite" or "low tier" UE or device refers to a wireless device that has a relatively low operating bandwidth compared to a "premium" UE or device that has a relatively high operating bandwidth. A lite UE may also be referred to as a "reduced capability" UE. For reduced capability devices in 5G NR, 3GPP is developing an "NR Light" standard that allows NR devices with reduced complexity and energy consumption to meet higher latency and data rate acquisition in a 5G NR environment (compared to narrowband IoT (NB-IoT) or LTE-M in an LTE environment). Thus, references herein to a lite or low tier UE or device may refer to a 5G NR device that uses NR Light, and references herein to a premium UE or device may refer to a 5G NR device that uses standard NR. Examples of lite UEs may include wearable devices (e.g., smart watches), mitigated / narrowband IoT devices, low-end mobile phones, and the like. Current operating bandwidths for these devices are approximately 5-20 megahertz (MHz), although some low tier UEs may have higher or lower operating bandwidths. Examples of premium UEs may include high-end mobile phones (e.g., smartphones), tablets, vehicles, etc. Premium UEs currently operate at bandwidths of 100 MHz or greater. Generally speaking, lite UEs have relatively lower bandwidths (e.g., less than 100 MHz), lower processing capabilities, and / or lower power budgets than premium UEs.

[0047]

[0057] As mentioned, network-based positioning often requires communication with multiple base stations. For example, high accuracy (e.g., accuracy of 3 m or less) positioning determination often requires multi-RTT, where RTT measurements are made between the UE and multiple base stations. However, the power requirements of communication with multiple base stations can often be burdensome for a lite UE. Moreover, a lite UE may not be able to obtain reference signals (e.g., PRS) from multiple base stations due to antenna losses, low bandwidth, fewer antennas, and reduced baseband capabilities compared to a premium UE. In addition, a lite UE has reduced transmit power, which may result in lower quality uplink (UL) measurements at the base station of RF signals transmitted by the lite UE.

[0048]

[0058] With this in mind, low power positioning techniques have been developed to allow a target UE (e.g., a lite UE) to be determined with high accuracy using a single base station and using the relatively low power used by the target UE. This can be accomplished by leveraging an anchor UE 420 (e.g., a premium UE), also called a "relay," that has a known location relative to the base station. Techniques for UE-assisted positioning and UE-based positioning can be used. Figure 4 helps illustrate that such low power UE positioning can be performed.

[0049]

[0059] It may be noted that operations for positioning of a target UE, such as performing beamforming, reference signal transmission, and signal measurements, are described herein with respect to a base station / TRP, but are not so limited. Alternative embodiments may utilize other wireless network nodes in addition to or as an alternative to a base station / TRP. This may include, for example, a device having a known location (e.g., either a permanent location or a temporary location) communicatively coupled to a location server. Thus, as used herein, the term "wireless network node" may refer to a base station / TRP, a network-connected mobile device (e.g., UE), a network-connected stationary device (e.g., wireless access point), etc., or combinations thereof. Subsequent embodiments describe the use of one or more "wireless network nodes," which may include, for example, any of these device types. Communications between a wireless network node and a location server may be relayed via other devices. For example, a wireless network node comprising a UE may communicate with a location server via a base station / TRP or other wireless access point. Additionally, in embodiments in which the wireless network node comprises a UE, the UE may transmit a reference signal, for example, via a side link (SL) interface.

[0050]

[0060] FIG. 4 is a simplified diagram illustrating how network-based position determination of a target UE 410 may be performed using a single wireless network node 405 (e.g., a serving base station of the target UE 410 and / or anchor UE 420), according to one embodiment. Here, positioning of the target UE 410 is accomplished using communication with an anchor UE 420 or relay, and both the target UE 410 and anchor UE 420 receive reference signals 450, 460 from the wireless network node 405. Use of a location server 160 may facilitate coordinating the transmission and measurement of the reference signals 450 and 460. Although multiple devices are shown as wireless network nodes 405, it may be noted that only a single device may be used. (These devices shown in FIG. 4 and subsequent figures are provided to illustrate various exemplary device types of wireless network nodes 405.)

[0051]

[0061] The location of the target UE 410 is determined by the distance R of the target UE 410 from the wireless network node 405. T , as well as the angle φ1. It may be noted that the baseline from which the angle φ1 is measured may be measured from true north or based on any coordinate system used by the network for positioning (e.g., geographic coordinates, East-North-Up (ENU), etc.). Determining these two variables may be achieved with the aid of the anchor UE 420, which may measure the reference signal 460 as well as the sidelink signal 470 provided by the target UE 410 in response to the target UE 410 receiving the reference signal 450.

[0052]

[0062] Distance R T may be determined based on the time difference between receipt of the reference signal 460 and receipt of the sidelink signal 470 at the anchor UE 420. Tand the distance R between the target UE 410 and the anchor UE 420. R The bond distance with R sum Then, R T To find this, we use the following formula:

[0053]

number

[0054]

[0063] If L is defined as the distance between the wireless network node 405 and the anchor UE 420, then equation (1) may be modified as follows:

[0055]

number

[0056]

[0064] Since the location of the anchor UE 420 is known (or can be determined in advance), the distance L can be obtained based on this anchor UE location and the known location of the wireless network node 405. (For example, in the case of a wireless network node 405 comprising a base station, this location can be obtained from an almanac of base station locations stored by the location server 160 and / or the anchor UE 420. For other types of wireless network nodes, the location server may store a similar almanac / database containing known locations of wireless network nodes (fixed and / or mobile).) Furthermore, R sum may be determined from the timing of transmission and reception of the reference signals 450, 460 and the sidelink signal 470. In particular, R sum can be calculated as follows:

[0057]

number

[0058] Here, T Rx,SL,relayis the time of arrival (ToA) of the sidelink signal 470 at the anchor UE 420, and T Rx,Uu,relay is the ToA of the reference signal 460 at the anchor UE 420, and T Tx,SL,UE is the time at which the target UE 410 transmits the sidelink signal 470, and T Rx,Uu,UE is the time when the reference signal 450 is received at the target UE 410, and c is the speed of the RF signal (e.g., the speed of light). Rx,SL,relay -T Rx,Uu,relay The target UE 410 can measure T Tx,SL,UE -T Rx,Uu,UE may be measured and provided to the anchor UE 420 for calculation of the position of the target UE 410. Alternatively, the anchor UE 420 may forward measurements taken by both the target UE 410 and the anchor UE 420 to the location server 160 for calculation of the location of the target UE 410.

[0059]

[0065] Returning to equation (2), the final variable needed to determine the location of the target UE 410 is the angle φ1. The angle φ1 can be determined from an AoD measurement of the reference signal 450 transmitted by the wireless network node 405. However, the AoD measurement may result in an undesirable amount of power being consumed by the target UE 410.

[0060]

[0066] Briefly, the AoD can be measured when the wireless network node 405 transmits a reference signal in each of a plurality of directions using beam sweeping, using a respective plurality of beams (e.g., as shown by beams 309-a to 309-f in FIG. 3). Using RSRP measurements of each beam at the target UE 410, the beam that is best aligned to the UE 105 (as having the highest value) can be identified. Additional techniques may be implemented to determine an accurate AoD based on the alignment. In the case of UE-based positioning, information about each beam (e.g., beam width and boresight) may be provided to the target UE 410 to enable the UE to calculate the AoD. Alternatively, in the case of UE-assisted positioning, the target UE 410 may provide the RSRP measurements to the location server 160, and the location server 160 may use the RSRP measurements and the beam information to calculate the AoD. Because the UE 105 may measure a large number of beams to perform AoD measurements (beam sweeping may involve, for example, 8 or 64 beams), these AoD measurements may consume a relatively large amount of power. Moreover, communicating the beam information for each of the beams to the target UE 410 may require a large amount of signaling overhead.

[0061]

[0067] Embodiments herein address these and other concerns by providing a differential AoA measurement that can be used in the low power positioning in FIG. 4. That is, rather than the target UE 410 making an AoD measurement or making an RSRP measurement for AoD estimation to determine the φ1 angle, the anchor UE 420 can make a differential AoA measurement to determine the angle θ1, i.e., the angle at the anchor UE 420 between the wireless network node 405 and the target UE 410. (For clarity, a differential AoA measurement comprises making two AoA measurements and determining the difference. When determining the angle θ1, the anchor UE 420 can make measurements of the sidelink signal 470 and the reference signal 460 and then take the difference.) The angle of arrival θ1 can then be used in a manner similar to the angle φ1 as previously described to determine the location of the target UE 410. In particular, the angle φ1 can be used in equation (2) to determine the distance R T Similarly, the distance R can be calculated using the angle θ1 using the following formula: R may be required.

[0062]

number

[0063]

[0068] This can save a lot of power at the target UE 410 because the target UE 410 can make a single measurement (e.g., the ToA at which the reference signal 450 arrives at the target UE 410 (e.g., T Rx,Uu,UE)). Moreover, the reference signal 450 may be transmitted by the wireless network node 405 using a wider beam. Furthermore, because the anchor UE 420 measures the differential AoA, if the signals 460 and 470 are received close in time, then a precise orientation of the anchor UE 420 at the time the measurement is made is not required. That is, if the angle ε corresponds to the orientation of the anchor UE, then if the change in the orientation of the anchor UE between the reception of the signal 460 and the reception of the signal 470 is negligible, then the angle ε can be assumed to represent a common offset of the measurements by the anchor UE 420 for both θ1 and θ2 (e.g., the anchor UE 420 measures θ1+ε and θ2+ε). As will be discussed in more detail later, embodiments may therefore ensure that the signals 460 and 470 are received close in time to help ensure negligible changes in the orientation of the UE. In that case, by ensuring that angle ε is common to both θ1 and θ2, ε can be cancelled out when calculating the difference θ2-θ1 (e.g., (θ1+ε)-(θ2+ε)) in equation (4). It can further be noted that reference signal 450 and reference signal 460 can comprise the same or different reference signals. Figures 5A and 5B show examples of this.

[0064]

[0069] 5A and 5B are diagrams of a wireless network node 405, a target UE 410, and an anchor UE 420 similar to that shown in FIG. 4, provided to illustrate how beams may be used differently in different embodiments and / or situations depending on the desired functionality. In FIG. 5A, for example, a single reference signal beam 510 is wide enough to be received by both the target UE 410 and the anchor UE 420, such that the reference signal beam 510 can be used in the position determination of the target UE 410 previously described. As can be seen, whether the reference signal beam 510 is wide enough may depend not only on the width of the reference signal beam, but also on how close the target UE 410 and the anchor UE 420 are to each other. (In some cases, for example, the target UE 410 and the anchor UE 420 may be close enough that a relatively narrow beam, such as that shown in FIG. 5B, may be used by both the target UE 410 and the anchor UE 420.) However, in FIG. 5B, the target UE 410 is aligned with the first reference signal beam 520 and the anchor UE 420 is more aligned with the second reference signal beam 530. In such cases, even if the anchor UE 420 can detect both the first reference signal beam 520 and the second reference signal beam 530, it may be preferable for the anchor UE 420 to take ToA measurements of the second reference signal beam 530 rather than the first reference signal beam 520 (e.g., due to a better SNR value for taking the ToA measurements). Although the reference signal beams 520, 530 may be transmitted at different times, since the time difference between the transmission of the first reference signal beam 520 and the second reference signal beam 530 is known, this time difference can be reflected in equation (3), such that R R It becomes possible to determine.

[0065]

[0070] It may be noted that when using a single wireless network node 405 for positioning, ambiguities may arise as a result of the differential AoA measurement since it is not an absolute measurement. For example, when determining the two-dimensional location of the target UE 410, the target UE 410 may have two possible locations (e.g., on the horizontal plane). An example of such ambiguity is shown in FIG. 6.

[0066]

[0071] FIG. 6 is a diagram similar to FIG. 4 and illustrates a simple configuration that may be used by a positioning system to determine the location of the target UE 410. (For simplicity, the location server 160 and other components are not shown.) Using the techniques described above, the anchor UE 420 can take the ToA and differential AoA measurements of reference signals transmitted by the first wireless network node 405-1 and the target UE 410 to solve for the variables in equations (3) and (4) above to determine the location of the target UE 410. However, in the absence of other data, a two-dimensional solution results in two possible locations: the actual location of the target UE 410 and the mirror position 610-1. Embodiments may resolve this ambiguity in any of a variety of manners.

[0067]

[0072] According to some embodiments, for example, the second wireless network node 405-2 can be used to resolve the ambiguity. In such an embodiment, the second wireless network node 405-2 and the target UE 410 can transmit reference signals, and the anchor UE 420 can use these reference signals to take ToA and differential AoA measurements. This again results in two possible solutions for the two-dimensional location of the target UE 410: the actual location and the mirror position 610-2. Using a common solution for the location of the target UE 410 based on reference signals from both wireless network nodes 405-1 and 405-2, the ambiguity can be resolved and the actual location of the target UE 410 can be determined.

[0068]

[0073] Although it is possible for the ambiguity to be resolved using additional wireless network nodes, other techniques may also be used depending on the desired capabilities, available data, and / or other factors. For example, according to some embodiments, the ambiguity may be resolved using tracking data, historical location data, etc. Additionally or alternatively, location data from additional anchor UEs may be leveraged (e.g., utilizing one or more additional anchor UEs as detailed above to find a common solution), as shown in more detail in FIG. 7, discussed below. The ambiguity may also be resolved using data from other positioning techniques, such as GNSS-based positioning or sensor / image-based positioning, as an additional or alternative method. Such data may come from the target UE 410, which may provide this information to the anchor UE 420 and / or the location server 160, i.e., whichever determines the location of the target UE.

[0069]

[0074] 7 is a simplified diagram illustrating a scenario in which location data from additional anchor UEs may be leveraged to resolve ambiguity, according to an embodiment, where multiple anchor UEs 420-1, 420-2, and 420-3 (collectively and generically referred to herein as simply anchor UEs 420) are used instead of a single anchor UE 420.

[0070]

[0075] The process of determining the location of the target UE 410 may be generally similar to the process shown in FIG. 4 and described herein. However, because multiple anchor UEs 420 are used, angle information may not be required. That is, the distance R T and angle θ T 4) from the wireless network node 405, and calculates the respective R sum (To reduce clutter, the direct reference signal is not shown in FIG. 7.) R sum is R T and each R R Since it is the sum of R sumUsing the values ​​of , a respective ellipse 780 for each anchor UE 420 may be formed, with the wireless network node 405 and the anchor UE 420 being the foci of the respective ellipse. (Again, to reduce clutter, only the applicable portion of the ellipse 780 is shown in FIG. 7.) Thus, resolving the location ambiguity of the target UE 410 may comprise determining the point to which the ellipses 780 converge. This technique may be used in addition to, or as an alternative to, other ambiguity resolution techniques. The number of anchor UEs 420 used to resolve the location ambiguity of the target UE 410 in this manner may vary depending on the circumstances. For example, more or fewer anchor UEs 420 than shown in FIG. 7 may be used.

[0071]

[0076] It may be noted that depending on the desired functionality, the reference signal and the sidelink signal may be the same or different. For example, a single reference signal 450 may be sent to the target UE 410, which may then send a respective sidelink signal 470 to each of the anchor UEs 420. In another example, the target UE 410 may receive a single reference signal 450 and send a single sidelink signal 470 to all or a subset of the anchor UEs 420. Alternatively, a different reference signal 450 may be used for each anchor UE 420, such that for each anchor UE, the target UE 410 receives a respective reference signal 450 and sends a corresponding respective sidelink signal 470 to the anchor UE. Different embodiments may employ different combinations of reference signals. Similarly, one or more reference signals (not shown in FIG. 7 but corresponding to the reference signal 460 in FIG. 4) from the wireless network node 405 to the anchor UE 420 may be used. (For example, if all anchor UEs 420 are in a single beam, a single reference signal may be used. Alternatively, different reference signals may be sent to different anchor UEs 420).

[0072]

[0077] The position and / or distance R of the target UE 410 R The determination of the values ​​of θ1 and θ2 may be performed by different entities depending on the desired functionality. This may depend, for example, on whether the positioning of the target UE 410 is UE-based (e.g., when a request for the location of the target UE 410 comes from the target UE 410 itself) or UE-assisted (e.g., when a request for the location of the target UE 410 comes from the network or from another entity outside the target UE, such as the external client 180 of FIG. 1 or the external client 230 of FIG. 2). Thus, the location of the target UE 410 may be determined using different processes. Additional details are provided below with respect to FIGS. 8-10, which illustrate some example processes.

[0073]

[0078] FIG. 8 is a call flow diagram illustrating an embodiment of a process for performing UE-based position determination of a target UE 410. As with other figures provided herein, FIG. 8 is provided as a non-limiting example. Additionally, alternative embodiments may perform some functions (e.g., exchange of pre-positioning data, ToA measurements, etc.) in a different order, simultaneously, etc. It may be noted that the arrows between the various components shown in FIG. 8 indicate messages or information being sent from one component to another. However, it will be understood that there may be any number of intervening devices, servers, etc. that may relay such messages, including other components in FIG. 8. (E.g., a message from the target UE 410 to the location server 160 may pass through the wireless network node 405 and possibly the anchor UE 420.) Additionally, although the wireless reference signals are referred to as PRSs (e.g., DL-PRS transmitted by the wireless network node 405 and SL-PRS transmitted by the target UE 410), alternative embodiments may utilize other wireless reference signal types.

[0074]

[0079] At block 805, the target UE 410 obtains a location request. This location request may come, for example, from an application (or app) executed by the target UE 410. It may be the result of a user interaction with the target UE 410, based on a determined schedule, or based on other triggers. Additionally or alternatively, the location request may come from a separate device (e.g., the anchor UE 420 or another device in communication with the target UE 410) requesting the location of the target UE 410.

[0075]

[0080] In response, the target UE 410 may generate a location request notification. As indicated by arrow 810, the request may be sent to the location server 160, which may coordinate the functionality of the various components illustrated in FIG. 8 to determine the location of the target UE 410. According to some embodiments, additional communication may occur between the target UE 410 and the location server 160 to determine the capabilities of the target UE 410 (e.g., including the capability of the target UE 410 to communicate with the anchor UE 420). In some embodiments, communication between the location server 160 and the target UE 410 may occur via an LPP positioning session.

[0076]

[0081] As shown, according to some embodiments, a location request notification may additionally be sent to the anchor UE 420. This may inform the anchor UE 420 of the location request received by the target UE 410 (at block 805) and may optionally trigger the anchor UE 420 to obtain the location of the anchor UE 420 at block 815 (as indicated by the dashed box). Again, the location request notification provided to the anchor UE 420 may be part of a larger communication exchange in case positioning capabilities are shared between the target UE 410 and the anchor UE 420. According to some embodiments, location may be performed between the target UE 410 and the anchor UE 420 over an existing sidelink connection. Alternatively, a new sidelink connection may be created in response to the location request received at block 805. According to some embodiments, the notification may be provided by the location server 160 in response to the location request notification received at arrow 810 by the location server 160, rather than the target UE 410 providing the location request notification at arrow 810.

[0077]

[0082] Selection of an anchor UE 420 for use in determining the position of a target UE 410 may be done in any of a variety of manners, depending on the desired functionality. For example, as mentioned, the target UE 410 may have an existing sidelink communication channel with the anchor UE 420 that can be leveraged for positioning purposes. In such cases, the anchor UE 420 may be selected based on the existing sidelink channel. Additionally or alternatively, the anchor UE 420 may be selected by the target UE 410 based on scanning for nearby anchor UEs and based on a confirmed ability to perform positioning in this manner. In some embodiments, a signal quality metric, such as, for example, SNR and / or RSSI, may be used to select the anchor UE 420. Using the signal quality measurements, an anchor UE 420 may be selected that has adequate signal quality to perform the functions described herein, but is not too close to the target UE 410 to cause positioning errors in determining the position of the target UE 410. Thus, in such embodiments, a range of SNR and / or RSSI values ​​may be selected to balance these considerations, and anchor UEs having SNR and / or RSSI values ​​that fall within this range may be selected in preference to other anchor UEs having SNR and / or RSSI values ​​that fall outside of this range. Other embodiments may utilize additional or alternative techniques for anchor UE selection.

[0078]

[0083] As mentioned, at block 815, the anchor UE 420 may optionally determine its position and / or motion data. As previously mentioned, the position of the anchor UE 420 may be used in determining the position of the target UE 410. Obtaining the position data may be performed in any of a variety of manners, including GNSS, dead reckoning, and / or other non-network means. Additionally or alternatively, the position determination for the anchor UE 420 may be network-based and may involve a location server 160 (not shown). In some embodiments, the anchor UE 420 may obtain a high-precision position determination based on, for example, a multi-RTT positioning based on communications with multiple wireless network nodes (which may include communications with the wireless network node 405). In the case of a multi-RTT positioning, the assistance data may include the location of each wireless network node for which RTT measurements are made.

[0079]

[0084] The motion data may be used to determine a time window for which the DL-PRS and SL-PRS are transmitted, which may be determined in any of a variety of manners. The anchor UE 420 may include a motion sensor, for example, that may be used to determine the movements that the anchor UE 420 makes.

[0080]

[0085] As shown by arrow 820, location server 160 and anchor UE 420 may exchange pre-positioning data in preparation for determining a position for target UE 410. This may include, for example, anchor UE 420 providing information to location server 160 regarding the capabilities of anchor UE 420 to perform AoA measurements. That is, anchor UE 420 may provide a capability report to location server 160 to indicate whether anchor UE 420 can perform differential AoA measurements.

[0081]

[0086] It may be noted that the capabilities of the anchor UE 420 in this regard may vary depending on the device type and other factors. As previously indicated, taking differential AoA measurements may be simpler for the anchor UE 420 to implement than taking absolute AoA measurements, since absolute AoA measurements may require real-time antenna orientation calibration for the anchor UE 420. On the other hand, differential AoA measurements are based on the difference between the first and second AoA measurements, rather than on the absolute orientation of either one of these measurements. Thus, some devices may only be able to take differential AoA measurements, rather than absolute AoA measurements. Other devices (e.g., devices with only a single antenna, etc.) may not be able to take either differential or absolute AoA measurements.

[0082]

[0087] It may further be noted that the device's capability of taking differential AoA measurements may be dynamic. To help ensure accurate differential AoA measurements, the anchor UE 420 should experience little or no motion between taking the first and second AoA measurements. Thus, according to some embodiments, the pre-positioning data provided at arrow 820 may further include motion data (e.g., indications of current or expected motion, motion status, etc.) that may affect the accuracy of the differential AoA measurements. This motion data may comprise the motion data obtained at block 815. The location server 160 may then take this motion information into account when coordinating the transmission of PRS resources for position determination of the target UE 410. The faster the motion (e.g., change in location and / or orientation of the anchor UE 420), the less accurate the differential AoA measurements may be.

[0083]

[0088] As a location server, the location server can help minimize any adverse effect that motion may have on the differential AoA measurements taken by the anchor UE 420 by ensuring the time-domain proximity of the positioning reference signals. In other words, if the location server 160 can schedule the transmission of DL-PRS by the wireless network node 405 and the transmission of SL-PRS by the target UE 410 to fall within the time-domain proximity, then motion by the anchor UE 420 may have little effect on the accuracy of the differential AoA measurements. The time window in which these reference signals are scheduled may depend on the accuracy requirements of the position request in block 805 as well as any motion of the anchor UE 420. Thus, the location server 160 can balance the impact of any motion of the anchor UE with the accuracy requirements when scheduling the transmission of the positioning reference signals. According to some embodiments, the time-domain proximity of the reference signals can be quantified based on the motion status of the anchor UE 420. According to some embodiments, a look-up table may be used to map different types of motion, speed, rotation speed, etc., to different time-domain proximity requirements. If the anchor UE's motion is static or its orientation is fixed, the requirements may be relaxed. Such time-domain proximity may also be explicitly indicated by the network, through associating one or more DL-PRS resources transmitted by the wireless network node with one or more SL-PRS resources transmitted by the target UE 410.

[0084]

[0089] Depending on the desired functionality, the time domain proximity of the first and second reference signals for the differential AoA measurements may be defined using various levels of granularity. For example, embodiments may define the time window for the measurements in terms of frames, subframes, slots, symbols, or other features (including sub-symbol features / times) of the Orthogonal Frequency Division Multiplexing (OFDM) regime utilized in NR or LTE communications. Because these features may occur on the scale of microseconds, the reference signals used within these described time windows can help ensure that minimal movement occurs between the first and second AoA measurements.

[0085]

[0090] Since there may be a time delay of milliseconds or seconds (or more) between the exchange of pre-positioning data at arrow 820 and the transmission / measurement of PRS resources, there may be variations in the motion of the anchor UE 420. That is, the motion, if any, reported in the pre-positioning data at arrow 820 may not precisely match the motion of the anchor UE 420 at the time of the AoA measurements of the DL-PRS and SL-PRS for the differential AoA measurements. With this in mind, some embodiments may further provide post-hoc reporting of the motion / motion status of the anchor UE 420. Just as the motion of the anchor UE 420 reported in the pre-positioning data may be used to determine the time window for performing the differential AoA measurements, the accuracy of the differential AoA may be determined using post-hoc motion data regarding the motion of the anchor UE 420 during the differential AoA measurements.

[0086]

[0091] According to some embodiments, location server 160 may schedule PRS resources (e.g., DL-PRS and SL-PRS) with a default time-domain proximity, i.e., if anchor UE 420 is unable to provide motion / motion status or (in some cases) regardless of the type of motion / motion status provided by anchor UE, location server 160 may schedule PRS resources to have sufficient time-domain proximity (e.g., around 20 ms, 11 ms, 5 ms, or less) to help ensure minimal motion during differential AoA measurements.

[0087]

[0092] At arrow 830, the location server 160 schedules the transmission and measurement of PRS resources. This may include providing the wireless network node 405 with a configuration for transmitting DL-PRS, providing the target UE 410 with a configuration for transmitting SL-PRS, and / or providing the target UE 420 with a configuration for measuring DL-PRS and SL-PRS. However, it may be noted that alternative embodiments may allow the anchor UE 420 or another UE (not shown) to schedule the transmission of SL-PRS by the target UE 410. For example, in some embodiments, the anchor UE 420 may configure a resource pool for positioning (RP-P) for the target UE 410. This may include configuring the target UE 410 with specific SL-PRS resources (subset of symbols, bandwidth, comb size, sequence ID, port number) within the configured RP-P. According to some embodiments, the location server 160 may configure the anchor UE 420 by indicating when the wireless network node 405 is scheduled to transmit DL-PRS, and the anchor UE 420 can then configure the target UE 410 with one or more SL-PRS resources, taking into account the time domain proximity considerations previously described.

[0088]

[0093] At arrow 840, the wireless network node 405 transmits the DL-PRS. As shown in Figures 5A and 5B, the DL-PRS (e.g., reference signal 460 of Figure 4) transmitted to the anchor UE 420 may be the same or different from the DL-PRS (e.g., reference signal 450) transmitted to the target UE 410. In either case, the anchor UE 420 takes ToA and AoA measurements of the DL-PRS at block 845, and the target UE 410 takes ToA measurements of the DL-PRS at block 850. As mentioned above, the ToA measurements can be used in positioning the target UE 410, for example, to solve equation (3) above. The AoA measurements of the DL-PRS by the anchor UE 420 at block 845 can be part of a differential AoA measurement taken by the anchor UE 420, which is later used to solve equation (4) above. Some embodiments may use separate DL-PRS for ToA and AoA measurements by the anchor UE 420, while other embodiments may choose to take both types of measurements of the same DL-PRS to help increase signaling efficiency.

[0089]

[0094] After measuring the ToA of the DL-PRS in block 850, the target UE 410 then measures the Rx-Tx time difference (e.g., the time difference T Tx,SL,UE -T Rx,Uu,UE ) may be determined. In particular, the Rx-Tx time difference is the time difference between the time the DL-PRS is received at the target UE 410 and the time the target UE 410 transmits (at arrow 860) the SL-PRS to be received by the anchor UE 420. Further at arrow 860, the target UE 410 then sends the SL-PRS to the anchor UE 420 along with the Rx-Tx time difference. As previously described, the SL-PRS may comprise a signal sent over a sidelink communication channel (e.g., sidelink signal 470).

[0090]

[0095] At block 865, the anchor UE 420 measures the ToA and AoA of the SL-PRS, which may be used to determine the location of the target UE 410, for example using equations (3) and (4). This may include, for example, the functionality at block 870, where the anchor UE 420 determines a differential AoA between the SL-PRS received from the target UE 410 and the DL-PRS received from the wireless network node 405.

[0091]

[0096] In addition, as shown in block 865, the anchor UE 420 may further take a time difference (RSTD) measurement between the SL-PRS and the DL-PRS. The RSTD measurement may be used to indicate, for example, the measurement quality of the differential AoA determined in block 870. According to some embodiments, this may be combined with motion data taken by the anchor UE 410 during the time period between receipt of the DL-PRS and receipt of the SL-PRS. A large amount of motion and / or a large RSTD measurement may result in an inaccurate differential AoA determination. According to some embodiments, this measurement quality indication may be reflected in the target UE's position determination (e.g., as a reduced level of accuracy of the determined position). Additionally or alternatively, if the motion and / or RSTD measurement exceeds a threshold (e.g., may exceed a threshold tolerance of inaccuracy for the target UE's position determination), the anchor UE 420 may abort the process of determining the target UE's position altogether.

[0092]

[0097] At block 875, the anchor UE 420 determines the location of the target UE 410. More specifically, the anchor UE 420 can use the differential AoA determined at block 870, the time difference of the ToA measurements taken at blocks 845 and 865, and the Rx-Tx time difference obtained from the target UE 410 to determine the relative location of the target UE 410 from the anchor UE 420 using equations (3) and (4). Additionally, the anchor UE 420 can use the known location of the anchor UE 420 (which may have been obtained at block 815) to determine the location of the target UE 410. This determined location can then be sent to the target UE 410 as indicated by arrow 880.

[0093]

[0098] As mentioned above, the DL-PRS transmitted at arrow 840 may be measured by both the anchor UE 420 and the target UE 410. In such cases, the SL-PRS is then transmitted by the target UE 410 at arrow 860, as shown in FIG. 8. However, there may be some cases or embodiments in which the DL-PRS and the SL-PRS are measured by the anchor UE 420 at substantially the same time. This may be done to reduce the time domain proximity of these signals to essentially zero. For example, in cases where the anchor UE 420 is experiencing a large amount of motion or is unable to provide the location server 160 with motion data for determining the time domain proximity of the signals, the location server 160 may schedule the DL-PRS and the SL-PRS at substantially the same time (e.g., using the same symbol in an OFDM communication). In such cases, the anchor UE 420 may thus be capable of processing the DL-PRS and the SL-PRS simultaneously. This capability of the anchor UE 420 may be provided to the location server 160, for example, as part of the pre-positioning data exchanged at arrow 820.

[0094]

[0099] Figure 9 is a call flow diagram illustrating an embodiment of a process for performing UE-assisted position determination of a target UE 410, where calculation and position determination are performed in a location server 160 based on information received from the anchor UE 420 and the target UE 410. Many of the operations performed in the process of Figure 9 may be similar to the operations performed in the process of Figure 8 previously described.

[0095]

[0100] The process may begin with a location request being obtained at location server 160, as shown in block 905. As previously indicated, UE-assisted positioning may be based on a request from an external client (e.g., external client 180 of FIG. 1 and / or external client 230 of FIG. 2). Additionally or alternatively, the request may come from a service within the wireless network that may require the location of the target UE 410 to provide certain functionality.

[0096]

[0101] In response to the position request, the location server 160 may notify the target UE 410 and (optionally) the anchor UE 420 of the position request via a position request notification, as shown by arrow 910. In some embodiments, this may comprise initiating a communications session between the location server 160 and the target UE 410 and / or between the location server 160 and the anchor UE 420.

[0097]

[0102] Elements 915-970 may be similar to the corresponding features in FIG. 8 previously described. However, subsequent elements may differ. For example, rather than the anchor UE 420 determining the location of the target UE 410, the anchor UE 420 provides measurement information to the location server 160, as indicated by arrow 973. This information may include measurement information (e.g., Rx-Tx time difference, ToA measurements, differential AoA measurements, etc.) used by the anchor UE 420 to determine the location of the target UE 410 in the process in FIG. 8. However, in the process of FIG. 9, the location server determines the location of the target UE in block 975. In addition, the location server 160 may provide the location of the target UE to the entity from which the location request received in block 905 originated.

[0098]

[0103] Sending measurement information from the anchor UE 420 to the location server at arrow 973 may be facilitated through new types of reports and / or information elements. For example, according to some embodiments, new location information elements (e.g., "NR-DL-Differential-AoA Location Information Elements") may be defined to enable reporting of differential AoA measurements by the anchor UE 420 to the location server 160. According to some embodiments, the AoA measurement report may include an ID pair comprising (i) a target UE ID and (ii) a wireless network node (e.g., a base station or TRP) ID. This new location information element may additionally or alternatively be applied to embodiments where differential AoA measurements of reference signals from two different wireless network nodes are performed by the UE, where each wireless network node is associated with a reference signal, the UE measures the differential AoA based on the two reference signals, and a determination of the UE's location may be based on the differential AoA. Additionally or alternatively, the AoA measurement report sent at arrow 973 may include a resource ID, a timestamp, and / or a measurement quality (eg, an RSTD measurement of time domain proximity between the SL-PRS and the DL-PRS).

[0099]

[0104] FIG. 10 is a flow diagram of a method 1000 for enabling low power positioning of a first mobile device using differential AoA, according to one embodiment. Here, the first mobile device may correspond to a target UE 410 and the second mobile device may correspond to an anchor UE 420, as described in FIGS. 4-8. Furthermore, as illustrated in the exemplary processes of FIGS. 8 and 9 and the description of FIGS. 4 and 9, the operations performed by different devices may vary depending on whether the positioning is UE-assisted or UE-based and / or other factors. Thus, the means for performing the functions illustrated in one or more of the blocks illustrated in FIG. 10 may be implemented by hardware and / or software components of the anchor UE 420 or the location server 160. Exemplary components of the anchor UE 420 are illustrated in FIG. 11 and described in more detail below. Exemplary components of the location server are illustrated in FIG. 12 and described in more detail below.

[0100]

[0105] At block 1010, the function comprises obtaining a differential AoA between a first AoA of a first wireless reference signal at a second mobile device and a second AoA of a second wireless reference signal at the second mobile device, where the first wireless reference signal is transmitted by a first wireless network node and the second wireless reference signal is transmitted by the first mobile device. Implementation of the function at block 1010 may vary depending on the type of device performing the function. For example, a location server may obtain the differential AoA by receiving the differential AoA from an anchor UE. On the other hand, the anchor UE itself may obtain the differential AoA as shown in FIG. 8 and FIG. 9 by taking the difference between AoA measurements of the first and second wireless reference signals. As mentioned in the above embodiments, the reference signals may comprise PRS reference signals (e.g., DL-PRS and SL-PRS), although the embodiments are not so limited. According to some embodiments, the first wireless reference signal may comprise a PRS, an SSB, a tracking reference signal (TRS), a channel state information reference signal (CSIRS), or a DMRS, or any combination thereof. Additionally or alternatively, the first wireless reference signal may comprise an SRS, to the extent that SRS may be used for SL communications. Additionally or alternatively, the second wireless reference signal may comprise an SL-PRS, a DMRS, or a CSIRS, or any combination thereof. The first and second wireless reference signals may be frequency domain multiplexed. Thus, according to some embodiments, the first wireless reference signal may be on a first wireless frequency band and the second wireless reference signal may be on a second frequency band.

[0101]

[0106] The means for performing the functions in block 1010 may comprise a bus 1105, a wireless communication interface 1130, a digital signal processor (DSP) 1120, a processing unit 1110, a memory 1160, and / or other components of a mobile device, as shown in Figure 11. Additionally or alternatively, the means for performing the functions in block 1010 may comprise a bus 1205, a communication subsystem 1230, a processing unit 1210, a working memory 1235, and / or other components of a computer system, as shown in Figure 12.

[0102]

[0107] At block 1020, the function comprises determining a location of the first mobile device based at least in part on the differential AoA. As shown in previously described embodiments, the determining may be further based on ToA measurements (e.g., to determine distance based on equation (3)). Accordingly, some embodiments may further comprise determining a first time difference, the first time difference comprising a time difference between (i) a time at which the third wireless reference signal transmitted by the network entity arrives at the first mobile device and (ii) a time at which the first mobile device transmits the second wireless reference signal. These embodiments further comprise determining a second time difference, the second time difference comprising a time difference between (i) a time at which the first wireless reference signal transmitted by the transmitting / receiving point arrives at the second mobile device and (ii) a time at which the second wireless reference signal arrives at the second mobile device. In such embodiments, determining the location of the first mobile device is further based on the first time difference and the second time difference. As mentioned, the reference signal used to measure the ToA at the anchor UE may be the same or a different reference signal as the reference signal used to measure the ToA at the target UE. Thus, according to some embodiments, the first wireless reference signal and the third wireless reference signal comprise the same signal. Alternatively, the first wireless reference signal and the third wireless reference signal may comprise different signals, and determining the location of the first mobile device is further based on a time difference between the transmission of the first wireless reference signal and the transmission of the third wireless reference signal.

[0103]

[0108] As mentioned, embodiments may further involve taking additional measurements and / or resolving the ambiguity. For example, according to some embodiments, method 1000 may further comprise obtaining an RSTD measurement indicative of a time difference between a time the first wireless reference signal is received at the second mobile device and a time the second wireless reference signal is received at the second mobile device, and determining the location of the first mobile device is performed based on determining that the time difference is less than a threshold. According to some embodiments, determining the location of the first mobile device may comprise resolving the location ambiguity of the first mobile device based on a second differential AoA indicative of an angle at the second mobile device between the second wireless network node and the first mobile device, historical location or tracking information for the first mobile device, or location information for the first mobile device obtained from the first mobile device, or any combination thereof.

[0104]

[0109] The means for performing the functions in block 1020 may comprise a bus 1105, a DSP 1120, a processing unit 1110, a memory 1160, and / or other components of a mobile device, as shown in Figure 11. Additionally or alternatively, the means for performing the functions in block 1020 may comprise a bus 1205, a processing unit 1210, a working memory 1235, and / or other components of a computer system, as shown in Figure 12.

[0105]

[0110] At block 1030, the function comprises providing a location of the first mobile device. As with other functions described herein, details of this function may vary depending on the type of device performing method 1000. For example, according to some embodiments, method 1000 is performed by a second mobile device. In such embodiments, providing the location of the first mobile device may comprise sending the location of the first mobile device from the second mobile device to the first mobile device. Additionally or alternatively, providing the location of the first mobile device may comprise providing the location of the first mobile device to an application executed by the second mobile device. Furthermore, for embodiments in which method 1000 is performed by a second mobile device, the method may further comprise obtaining motion data relating to the movement of the second mobile device prior to obtaining the differential AoA, and sending information indicative of the motion data to a location server. According to some embodiments, method 1000 may further comprise sending information indicative of the capability of the second mobile device to determine the differential AoA from the second mobile device to a location server.

[0106]

[0111] When method 1000 is implemented by a location server, a different set of functions may be implemented. For example, in such an embodiment, obtaining the differential AoA comprises obtaining the differential AoA from a second mobile device. Such an embodiment may further comprise receiving motion data relating to motion of the second mobile device, determining a time domain proximity for the first wireless reference signal and the second wireless reference signal based at least in part on the motion data, and configuring the first wireless network node to send the first wireless signal, configuring the first mobile device to send the second wireless signal, or both based at least in part on the time domain proximity. Additionally or alternatively, an embodiment may comprise receiving a request for a position of the first mobile device from a requesting entity at the location server, and providing the position of the first mobile device comprises sending the position of the first mobile device from the location server to the requesting entity.

[0107]

[0112] The means for performing the functions in block 1030 may comprise the bus 1105, the wireless communication interface 1130, the DSP 1120, the processing unit 1110, the memory 1160, and / or other components of a mobile device, as shown in Figure 11. Additionally or alternatively, the means for performing the functions in block 1030 may comprise the bus 1205, the communication subsystem 1230, the processing unit 1210, the working memory 1235, and / or other components of a computer system, as shown in Figure 12.

[0108]

[0113] FIG. 11 illustrates one embodiment of a mobile device 1100, which may be utilized as a target UE, anchor UE, or other UE described hereinabove (e.g., in conjunction with FIGS. 1-9), including a UE operating as a wireless network node. For example, the mobile device 1100 may perform one or more of the functions of the method illustrated in FIG. 10. It should be noted that FIG. 11 is intended to provide only a generalized illustration of various components, and any or all of these components may be utilized as appropriate. It may be noted that in some instances, the components illustrated by FIG. 11 may be localized in a single physical device and / or distributed among various networked devices that may be disposed in different physical locations. Additionally, as previously described, the functions of the UE discussed in the previously described embodiments may be performed by one or more of the hardware and / or software components illustrated in FIG. 11.

[0109]

[0114] The mobile device 1100 is shown with hardware elements that may be electrically coupled (or in other communication, as appropriate) via a bus 1105. The hardware elements may include a processing unit 1110, which may include, but is not limited to, one or more general-purpose processors, one or more special-purpose processors (DSP chips, graphics acceleration processors, application specific integrated circuits (ASICs), etc.), and / or other processing structures or means. As shown in FIG. 11, some embodiments may have a separate DSP 1120 depending on the desired functionality. Location determination and / or other determinations based on wireless communication may be provided in the processing unit 1110 and / or the wireless communication interface 1130 (discussed below). The mobile device 1100 may also include one or more input devices 1170, which may include, but is not limited to, one or more keyboards, touch screens, touch pads, microphones, buttons, dials, switches, etc., and one or more output devices 1115, which may include, but is not limited to, one or more displays (e.g., touch screens), light emitting diodes (LEDs), speakers, etc.

[0110]

[0115] The mobile device 1100 may also include a wireless communication interface 1130, which may comprise, but is not limited to, a modem, a network card, an infrared communication device, a wireless communication device, and / or a chipset (such as a Bluetooth device, an IEEE 802.11 device, an IEEE 802.15.4 device, a Wi-Fi device, a WiMAX device, a WAN device, and / or various cellular devices), etc., that may enable the mobile device 1100 to communicate with other devices as described in the above embodiments. The wireless communication interface 1130 may enable data and signaling to be communicated (e.g., transmitted and received) with wireless network nodes of the network, such as via eNBs, gNBs, ng-eNBs, TRPs, access points, various base stations and / or other access node types, and / or other network components, computer systems, and / or any other electronic devices (such as UEs / mobile devices) communicatively coupled to the wireless network nodes, as described herein. The communication may occur via one or more wireless communication antennas 1132 that send and / or receive wireless signals 1134. According to some embodiments, the wireless communication antenna 1132 may comprise multiple individual antennas, an antenna array, or any combination thereof.

[0111]

[0116] Depending on the desired functionality, the wireless communication interface 1130 may comprise separate receivers and transmitters, or any combination of transceivers, transmitters, and / or receivers, for communicating with base stations (e.g., ng-eNBs and gNBs) and other terrestrial transceivers, such as wireless devices and access points. The mobile device 1100 may communicate with various data networks, which may comprise various network types. For example, a wireless wide area network (WWAN) may be a CDMA network, a time division multiple access (TDMA) network, a frequency division multiple access (FDMA) network, an orthogonal frequency division multiple access (OFDMA) network, a single carrier frequency division multiple access (SC-FDMA) network, a WiMAX (IEEE 802.16) network, etc. The CDMA network may implement one or more RATs, such as CDMA2000, WCDMA, etc. CDMA2000 includes IS-95, IS-2000, and / or IS-856 standards. The TDMA network may implement Global System for Mobile Communications (GSM), Digital Advanced Mobile Phone System (D-AMPS), or some other RAT. The OFDMA network may employ LTE, LTE Advanced, 5G NR, etc. 5G NR, LTE, LTE Advanced, GSM, and WCDMA are described in documents from 3GPP. CDMA2000 is described in documents from an organization named "3rd Generation Partnership Project X3" (3GPP2). 3GPP and 3GPP2 documents are publicly available. The wireless local area network (WLAN) may also be an IEEE 802.11x network, and the wireless personal area network (WPAN) may be a Bluetooth network, an IEEE 802.15x, or some other type of network. The techniques described herein may also be used for any combination of WWAN, WLAN, and / or WPAN.

[0112]

[0117] The mobile device 1100 may further include sensors 1140. The sensors 1140 may comprise, without limitation, one or more inertial sensors and / or other sensors (e.g., accelerometers, gyroscopes, cameras, magnetometers, altimeters, microphones, proximity sensors, light sensors, barometers, etc.), some of which may be used to obtain positional relationships measurements and / or other information.

[0113]

[0118] An embodiment of the mobile device 1100 may also include a GNSS receiver 1180 capable of receiving signals 1184 from one or more Global Navigation Satellite System (GNSS) satellites using an antenna 1182 (which may be similar to antenna 1132). Positioning based on GNSS signal measurements may be utilized to supplement and / or incorporate the techniques described herein. The GNSS receiver 1180 may extract a position of the mobile device 1100 using conventional techniques from GNSS satellites 110 of a GNSS system, such as Global Positioning System (GPS), Galileo, GLONASS, Japan's Quasi-Zenith Satellite System (QZSS), Indian Regional Navigation Satellite System (IRNSS), China's Beidou Navigation Satellite System (BDS), etc. Moreover, the GNSS receiver 1180 may be used with various augmentation systems (e.g., Satellite-Based Augmentation Systems (SBAS)) that may be associated with or otherwise enabled for use with one or more global and / or regional navigation satellite systems, such as, for example, the Wide Area Augmentation System (WAAS), the European Geostationary Navigation Overlay Service (EGNOS), the Multifunction Satellite Augmentation System (MSAS), and the Geo-Augmented Navigation System (GAGAN).

[0114]

[0119] It may be noted that although the GNSS receiver 1180 is shown as a separate component in FIG. 11, the embodiments are not so limited. The term "GNSS receiver" as used herein may comprise hardware and / or software components configured to obtain GNSS measurements (measurements from GNSS satellites). In some embodiments, the GNSS receiver may thus comprise a measurement engine executed (as software) by one or more processing units, such as the processing unit 1110, the DSP 1120, and / or a processing unit (e.g., in a modem) within the wireless communication interface 1130. The GNSS receiver may also include a positioning engine, which in some cases may use the GNSS measurements from the measurement engine to determine the position of the GNSS receiver using an extended Kalman filter (EKF), weighted least squares (WLS), a hatch filter, a particle filter, etc. The positioning engine may also be executed by one or more processing units, such as the processing unit 1110 or the DSP 1120.

[0115]

[0120] The mobile device 1100 may further include and / or be in communication with memory 1160. The memory 1160 may include local and / or network accessible storage, disk drives, drive arrays, optical storage devices, solid-state storage devices, such as, but not limited to, random access memory (RAM) and / or read-only memory (ROM), which may be programmable, flash updatable, etc. Such storage devices may be configured to implement any suitable data store, including, but not limited to, various file systems, database structures, etc.

[0116]

[0121] The memory 1160 of the mobile device 1100 may also comprise software elements (not shown in FIG. 11 ) including an operating system, device drivers, executable libraries, and / or other code such as one or more application programs that may comprise computer programs provided by various embodiments and / or that may be designed to implement methods and / or configure systems provided by other embodiments as described herein. By way of example only, one or more procedures described with respect to the methods discussed above may be implemented as code and / or instructions in the memory 1160 executable by the mobile device 1100 (and / or the processing unit 1110 or DSP 1120 within the mobile device 1100). In one aspect, then, such code and / or instructions may be used to configure and / or adapt a general-purpose computer (or other device) to perform one or more operations in accordance with the described methods.

[0117]

[0122] FIG. 12 is a block diagram of an embodiment of a computer system 1200 that may be used in whole or in part to provide the functionality of one or more network components described in the embodiments herein (e.g., the location server 160 of FIGS. 1, 4, 8, and 9, and / or the LMF of FIG. 2). It should be noted that FIG. 12 is intended only to provide a generalized illustration of the various components, and any or all of these components may be utilized as appropriate. FIG. 12 thus broadly illustrates how individual system elements may be implemented in a relatively separated or more relatively integrated manner. In addition, it may be noted that the components illustrated by FIG. 12 may be localized in a single device and / or distributed among various networked devices that may be disposed in different geographic locations.

[0118]

[0123] A computer system 1200 is shown comprising hardware elements that may be electrically coupled (or in other suitable communication) via a bus 1205. The hardware elements may include a processing unit 1210, which may comprise, but is not limited to, one or more general purpose processors, one or more special purpose processors (digital signal processing chips, graphics acceleration processors, etc.), and / or other processing structures that may be configured to perform one or more of the methods described herein. The computer system 1200 may also comprise one or more input devices 1215, which may comprise, but is not limited to, a mouse, keyboard, camera, microphone, etc., and one or more output devices 1220, which may comprise, but is not limited to, a display device, printer, etc.

[0119]

[0124] Computer system 1200 may further include (and / or be in communication with) one or more non-transitory storage devices 1225, which may comprise, but are not limited to, local and / or network accessible storage and / or solid-state storage devices, such as, but not limited to, disk drives, drive arrays, optical storage devices, RAM and / or ROM, which may be programmable, flash updatable, etc. Such storage devices may be configured to implement any suitable data store, including, but not limited to, various file systems, database structures, etc. Such data stores may include databases and / or other data structures used to store and manage messages and / or other information to be sent to one or more devices via the hub, as described herein.

[0120]

[0125] The computer system 1200 may also include a communication subsystem 1230, which may comprise wireless communication technologies managed and controlled by a wireless communication interface 1233, as well as wired technologies (Ethernet, coaxial communication, Universal Serial Bus (USB), etc.). The wireless communication interface 1233 may comprise wireless signals 1255 (e.g., signals according to 5G NR or LTE) via a wireless antenna 1250. Thus, the communication subsystem 1230 may comprise a modem, a network card (wireless or wired), an infrared communication device, a wireless communication device, and / or a chipset, etc., that may enable the computer system 1200 to communicate over any or all of the communication networks described herein to any device on the respective network, including UEs / mobile devices, base stations and / or other wireless network nodes, and / or any other electronic device described herein. Thus, the communication subsystem 1230 may be used to receive and transmit data as described in the embodiments herein.

[0121]

[0126] In many embodiments, computer system 1200 further comprises working memory 1235, which may comprise a RAM or ROM device, as described above. Software elements shown as being located within working memory 1235 may comprise computer programs provided by various embodiments, as described herein, and / or may comprise other code, such as an operating system 1240, device drivers, executable libraries, and / or one or more applications 1245, which may be designed to implement methods and / or configure systems provided by other embodiments. By way of example only, one or more procedures described with respect to the methods discussed above may be implemented as code and / or instructions executable by a computer (and / or a processing unit within a computer), in one aspect, where such code and / or instructions may be used to configure and / or adapt a general-purpose computer (or other device) to perform one or more operations in accordance with the methods described.

[0122]

[0127] A set of these instructions and / or code may be stored on a non-transitory computer-readable storage medium, such as storage device 1225 described above. In some cases, the storage medium may be incorporated within a computer system, such as computer system 1200. In other embodiments, the storage medium may be separate from the computer system (e.g., a removable medium such as an optical disk) and / or may be provided in an installation package such that the storage medium may be used to program, configure, and / or adapt a general-purpose computer with the instructions / code stored thereon. These instructions may take the form of executable code that is executable by computer system 1200 and / or may take the form of source code and / or installable code that takes the form of executable code when compiled and / or installed on computer system 1200 (e.g., using any of a variety of commonly available compilers, installation programs, compression / decompression utilities, etc.).

[0123]

[0128] It will be apparent to those skilled in the art that substantial variations may be made according to particular requirements. For example, customized hardware may be used and / or particular elements may be implemented in hardware, software (including portable software such as applets), or both. Furthermore, connection to other computing devices, such as network I / O devices, may be employed.

[0124]

[0129] With respect to the accompanying figures, components that may include memory may include non-transitory machine-readable media. As used herein, the terms "machine-readable media" and "computer-readable media" refer to any storage medium that participates in providing data that causes a machine to operate in a specific manner. In the embodiments provided above, various machine-readable media may participate in providing instructions / code to a processing unit and / or other devices for execution. Additionally or alternatively, machine-readable media may be used to store and / or transport such instructions / code. In many implementations, the computer-readable media is a physical and / or tangible storage medium. Such media may take many forms, including, but not limited to, non-volatile media and volatile media. Common forms of computer-readable media include, for example, magnetic and / or optical media, any other physical media with a pattern of holes, RAM, programmable ROM (PROM), erasable PROM (EPROM), flash EPROM, any other memory chip or cartridge, or any other medium from which a computer can read instructions and / or code.

[0125]

[0130] The methods, systems, and devices discussed herein are examples. Various embodiments may omit, substitute, or add various procedures or components as appropriate. For example, features described with respect to some embodiments may be combined in various other embodiments. Various aspects and elements of the embodiments may be combined in a similar manner. Various components of the diagrams provided herein may be implemented in hardware and / or software. Also, because technology evolves, many of the elements are examples that do not limit the scope of the disclosure to those particular examples.

[0126]

[0131] It has proven convenient at times, primarily for reasons of common usage, to refer to such signals as bits, information, values, elements, symbols, characters, variables, terms, numbers, numerals, or the like. It should be understood, however, that all of these or similar terms are to be associated with appropriate physical quantities and are merely convenient labels. Unless otherwise indicated, and as is clear from the above discussion, it should be appreciated that throughout this specification discussions utilizing terms such as "processing," "calculating," "calculating," "determining," "ascertaining," "identifying," "associating," "measuring," "performing," and the like refer to acts or processes of a particular apparatus, such as a special purpose computer or similar special purpose electronic computing device. In the context of this specification, therefore, a special purpose computer or similar special purpose electronic computing device is capable of manipulating or transforming signals that are commonly represented as physical electronic, electrical, or magnetic quantities within memories, registers, or other information storage, transmission, or display devices of the special purpose computer or similar special purpose electronic computing device.

[0127]

[0132] The terms "and" and "or" as used herein may include a variety of meanings that are also expected to depend, at least in part, on the context in which such terms are used. In general, "or," when used to associate a list, such as A, B, or C, is intended to mean A, B, and C, used herein in an inclusive sense, as well as A, B, or C, used herein in an exclusive sense. In addition, the term "one or more" as used herein may be used to describe any feature, structure, or characteristic in the singular, or may be used to describe any combination of features, structures, or characteristics. However, it should be noted that this is merely an illustrative example, and claimed subject matter is not limited to this example. Furthermore, the term "at least one of," when used to associate a list, such as A, B, or C, may be interpreted to mean any combination of A, B, and / or C, such as A, AB, AA, AAB, AABBCCC, etc.

[0128]

[0133] Although several embodiments have been described, various modifications, alternative configurations, and equivalents may be used without departing from the spirit of the present disclosure. For example, the above elements may only be components of a larger system, where other rules may take precedence over or otherwise modify the application of the various embodiments. Also, some steps may be performed before, during, or after the above elements are considered. Thus, the above description does not limit the scope of the present disclosure.

[0129]

[0134] In view of this description, embodiments may include various combinations of features. Example implementations are described in the following numbered clauses.

[0130] Clause 1: A method for enabling low power positioning of a first mobile device using differential angle of arrival (AoA), the method comprising: obtaining a differential AoA between a first AoA of a first wireless reference signal at a second mobile device and a second AoA of a second wireless reference signal at the second mobile device, where the first wireless reference signal is transmitted by a first wireless network node and the second wireless reference signal is transmitted by the first mobile device; determining a location of the first mobile device based at least in part on the differential AoA; and providing a location of the first mobile device.

[0131] Clause 2: The method of clause 1, further comprising obtaining a reference signal time difference (RSTD) measurement indicative of a time difference between a time when the first wireless reference signal is received at the second mobile device and a time when the second wireless reference signal is received at the second mobile device, and determining the location of the first mobile device based on determining that the time difference is less than a threshold.

[0132] Clause 3: The method of clause 1 or 2, wherein determining a location of the first mobile device comprises resolving ambiguity of a location of the first mobile device based on a second differential AoA indicating an angle at the second mobile device between the second wireless network node and the first mobile device, historical location information or tracking information for the first mobile device, or location information for the first mobile device obtained from the first mobile device, or any combination thereof.

[0133] Clause 4: Any of the methods of clauses 1 to 3, implemented by a second mobile device.

[0134] Clause 5: The method of clause 4, wherein providing the location of the first mobile device comprises sending the location of the first mobile device from the second mobile device to the first mobile device.

[0135] Clause 6: The method of clause 4 or 5, wherein providing the location of the first mobile device comprises providing the location of the first mobile device to an application executed by the second mobile device.

[0136] Clause 7: The method of any of clauses 4 to 6, further comprising: before obtaining the differential AoA, obtaining motion data relating to a motion of the second mobile device; and sending information indicative of the motion data to the location server.

[0137] Clause 8: The method of any of clauses 4-7, further comprising sending information from the second mobile device to the location server indicating a capability of the second mobile device for determining the differential AoA.

[0138] Clause 9: The method of any of clauses 1-3, wherein the method is performed by a location server and obtaining the differential AoA comprises receiving the differential AoA from the second mobile device.

[0139] Clause 10: The method of clause 9, further comprising receiving motion data relating to motion of a second mobile device, determining a time domain proximity for the first wireless reference signal and the second wireless reference signal based at least in part on the motion data, and configuring the first wireless network node to send the first wireless reference signal or configuring the first mobile device to send the second wireless reference signal, or both, based at least in part on the time domain proximity.

[0140] Clause 11: The method of clause 9 or 10, further comprising receiving a request for a location of the first mobile device from a requesting entity at the location server, and providing the location of the first mobile device comprises sending the location of the first mobile device from the location server to the requesting entity.

[0141] Clause 12: The method of any of clauses 1 to 11, wherein the first wireless reference signal comprises a positioning reference signal (PRS), a synchronization signal block (SSB), a tracking reference signal (TRS), a channel state information reference signal (CSIRS), or a demodulation reference signal (DMRS), or any combination thereof.

[0142] Clause 13: The method of any of clauses 1-12, wherein the second wireless reference signal comprises a sidelink PRS (SL-PRS), a DMRS, or a CSIRS, or any combination thereof.

[0143] Clause 14: The method of any of clauses 1-13, wherein the first wireless reference signal is on a first wireless frequency band and the second wireless reference signal is on a second frequency band.

[0144] Clause 15: The method of any of clauses 1-14, further comprising: determining a first time difference, where the first time difference comprises a time difference between a time when a third wireless reference signal transmitted by the network entity arrives at the first mobile device and a time when the first mobile device transmits the second wireless reference signal; and determining a second time difference, where the second time difference comprises a time difference between a time when the first wireless reference signal transmitted by the transmitting / receiving point arrives at the second mobile device and a time when the second wireless reference signal arrives at the second mobile device; and determining a location of the first mobile device is further based on the first time difference and the second time difference.

[0145] Clause 16: The method of any of clauses 1-15, wherein the first wireless reference signal and the third wireless reference signal comprise the same signal.

[0146] Clause 17: The method of any of clauses 1-15, wherein the first wireless reference signal and the third wireless reference signal comprise different signals, and determining the location of the first mobile device is further based on a time difference between transmission of the first wireless reference signal and transmission of the third wireless reference signal.

[0147] Clause 18: A device that enables low power positioning of a first mobile device using differential angle of arrival (AoA), comprising: a transceiver; a memory; and one or more processing units communicatively coupled to the transceiver and the memory, wherein the one or more processing units are configured to: obtain, via the transceiver, a differential AoA between a first AoA of a first wireless reference signal at a second mobile device and a second AoA of a second wireless reference signal at the second mobile device, where the first wireless reference signal is transmitted by a first wireless network node and the second wireless reference signal is transmitted by the first mobile device; determine a location of the first mobile device based at least in part on the differential AoA; and provide a location of the first mobile device.

[0148] Clause 19: The device of clause 18, wherein the one or more processing units are further configured to obtain a reference signal time difference (RSTD) measurement indicative of a time difference between a time when the first wireless reference signal is received at the second mobile device and a time when the second wireless reference signal is received at the second mobile device, and the one or more processing units are configured to determine a location of the first mobile device based on determining that the time difference is less than a threshold.

[0149] Clause 20: The device of clause 18 or 19, wherein to determine a position of the first mobile device, the one or more processing units are configured to resolve ambiguity in a position of the first mobile device based on a second differential AoA indicating an angle at the second mobile device between a second wireless network node and the first mobile device, historical location information or tracking information for the first mobile device, or location information for the first mobile device obtained from the first mobile device, or any combination thereof.

[0150] Clause 21: A device according to any one of clauses 18 to 20, comprising a second mobile device.

[0151] Clause 22: The device of clause 21, wherein the one or more processing units are configured to send a location of the first mobile device from the second mobile device to the first mobile device via the transceiver to provide a location of the first mobile device.

[0152] Clause 23: The device of clause 21 or 22, wherein to provide the location of the first mobile device, the one or more processing units are configured to provide the location of the first mobile device to an application executed by the second mobile device.

[0153] Clause 24: A device of any of clauses 21 to 23, wherein the one or more processing units are further configured to, before obtaining the differential AoA, obtain motion data relating to a movement of the second mobile device, and send information indicative of the motion data to the location server via the transceiver.

[0154] Clause 25: The device of any of clauses 21 to 24, wherein the one or more processing units are further configured to send, via the transceiver, information indicating a capability of the second mobile device to determine the differential AoA to the location server.

[0155] Clause 26: The device of any of clauses 18 to 20, wherein the device comprises a location server, and wherein the one or more processing units are configured to receive the differential AoA from the second mobile device to obtain the differential AoA.

[0156] Clause 27: The device of clause 26, wherein the one or more processing units are further configured to: receive motion data relating to motion of the second mobile device; determine a time-domain proximity for the first wireless reference signal and the second wireless reference signal based at least in part on the motion data; and configure the first wireless network node to send the first wireless reference signal or configure the first mobile device to send the second wireless reference signal, or both, based at least in part on the time-domain proximity.

[0157] Clause 28: The device of clause 26 or 27, wherein the one or more processing units are further configured to receive a request for a location of the first mobile device from a requesting entity via the transceiver, and wherein the one or more processing units are configured to send the location of the first mobile device to the requesting entity via the transceiver to provide the location of the first mobile device.

[0158] Clause 29: The device of any of clauses 18 to 28, wherein the first wireless reference signal comprises a positioning reference signal (PRS), a synchronization signal block (SSB), a tracking reference signal (TRS), a channel state information reference signal (CSIRS), or a demodulation reference signal (DMRS), or any combination thereof.

[0159] Clause 30: The second wireless reference signal is a sidelink PRS (SL-PRS), a DMRS, or a CSIRS, or any combination thereof. A device according to any of clauses 18 to 29 comprising:

[0160] Clause 31: A device of any of clauses 18 to 30, wherein the first wireless reference signal is on a first wireless frequency band and the second wireless reference signal is on a second frequency band.

[0161] Clause 32: The device of any of clauses 18-31, wherein the one or more processing units are further configured to: determine a first time difference, where the first time difference comprises a time difference between a time when a third wireless reference signal transmitted by the network entity arrives at the first mobile device and a time when the first mobile device transmits the second wireless reference signal; and determine a second time difference, where the second time difference comprises a time difference between a time when the first wireless reference signal transmitted by the transmitting / receiving point arrives at the second mobile device and a time when the second wireless reference signal arrives at the second mobile device; and wherein determining a location of the first mobile device is further based on the first time difference and the second time difference.

[0162] Clause 33: The device of any of clauses 18 to 32, wherein the first wireless reference signal and the third wireless reference signal comprise the same signal.

[0163] Clause 34: The device of any of clauses 18 to 32, wherein the first wireless reference signal and the third wireless reference signal comprise different signals, and the one or more processing units are further configured to determine a location of the first mobile device further based on a time difference between transmission of the first wireless reference signal and transmission of the third wireless reference signal.

[0164] Clause 35: A device that enables low power positioning of a first mobile device using differential angle of arrival (AoA), comprising: means for obtaining a differential AoA between a first AoA of a first wireless reference signal at a second mobile device and a second AoA of a second wireless reference signal at the second mobile device, where the first wireless reference signal is transmitted by a first wireless network node and the second wireless reference signal is transmitted by the first mobile device; means for determining a location of the first mobile device based at least in part on the differential AoA; and means for providing a location of the first mobile device.

[0165] Clause 36: The device of clause 35, further comprising means for obtaining a reference signal time difference (RSTD) measurement indicative of a time difference between a time when the first wireless reference signal is received at the second mobile device and a time when the second wireless reference signal is received at the second mobile device, wherein the means for determining a location of the first mobile device is configured to determine a location of the first mobile device based on determining that the time difference is less than a threshold.

[0166] Clause 37: The device of clause 35 or 36, wherein the means for determining a position of the first mobile device comprises means for resolving ambiguity of a position of the first mobile device based on a second differential AoA indicating an angle at the second mobile device between the second wireless network node and the first mobile device, historical location information or tracking information for the first mobile device, or location information for the first mobile device obtained from the first mobile device, or any combination thereof.

[0167] Clause 38: A device according to any one of clauses 35 to 37, comprising a second mobile device.

[0168] Clause 39: The device of clause 38, wherein the device comprises a location server, and wherein the means for obtaining the differential AoA comprises means for receiving the differential AoA from the second mobile device.

[0169] Clause 40: A non-transitory computer-readable medium storing instructions for enabling low power positioning of a first mobile device using differential angle of arrival (AoA), the instructions comprising: code for obtaining a differential AoA between a first AoA of a first wireless reference signal at a second mobile device and a second AoA of a second wireless reference signal at the second mobile device, where the first wireless reference signal is transmitted by a wireless network node and the second wireless reference signal is transmitted by the first mobile device; code for determining a location of the first mobile device based at least in part on the differential AoA; and code for providing a location of the first mobile device.

Claims

1. 1. A method for enabling low power positioning of a first mobile device using differential angle of arrival (AoA), comprising: obtaining a differential AoA between a first AoA of a first wireless reference signal at a second mobile device and a second AoA of a second wireless reference signal at the second mobile device, wherein: the first wireless reference signal is transmitted by a first wireless network node; the second wireless reference signal being transmitted by the first mobile device; determining a location of the first mobile device based at least in part on the differential AoA; and Providing a location of the first mobile device; and A method for providing the above.

2. 2. The method of claim 1, further comprising obtaining a reference signal time difference (RSTD) measurement indicative of a time difference between a time when the first wireless reference signal is received at the second mobile device and a time when the second wireless reference signal is received at the second mobile device, and determining a location of the first mobile device based on determining that the time difference is less than a threshold.

3. Determining a location of the first mobile device includes: a second differential AoA indicative of an angle at the second mobile device between a second wireless network node and the first mobile device; historical location or tracking information for the first mobile device; or location information about the first mobile device obtained from the first mobile device; or Any combination of these 2. The method of claim 1, comprising resolving the location ambiguity of the first mobile device based on:

4. The method of claim 1 , wherein the method is performed by the second mobile device.

5. The method of claim 4 , wherein providing the location of the first mobile device comprises sending the location of the first mobile device from the second mobile device to the first mobile device.

6. The method of claim 4 , wherein providing the location of the first mobile device comprises providing the location of the first mobile device to an application executed by the second mobile device.

7. Before obtaining the differential AoA, acquiring motion data relating to a motion of the second mobile device; sending information indicative of the motion data to a location server; The method of claim 4 further comprising:

8. 5. The method of claim 4, further comprising sending information from the second mobile device to a location server indicative of a capability of the second mobile device to determine the differential AoA.

9. The method of claim 1 , wherein the method is performed by a location server and obtaining the differential AoA comprises receiving the differential AoA from the second mobile device.

10. receiving motion data relating to a movement of the second mobile device; determining a time domain proximity for the first wireless reference signal and the second wireless reference signal based at least in part on the motion data; configuring the first wireless network node to transmit the first wireless reference signal, configuring the first mobile device to transmit the second wireless reference signal, or both, based at least in part on the time domain proximity; The method of claim 9 further comprising:

11. 10. The method of claim 9, further comprising receiving a request for the location of the first mobile device from a requesting entity at the location server, and wherein providing the location of the first mobile device comprises sending the location of the first mobile device from the location server to the requesting entity.

12. determining a first time difference, wherein the first time difference is: a time at which a third wireless reference signal transmitted by a network entity arrives at the first mobile device; a time when the first mobile device transmits a second wireless reference signal; With a time difference between determining a second time difference, wherein the second time difference is: a time at which the first wireless reference signal transmitted by the first wireless network node arrives at the second mobile device; a time when the second wireless reference signal arrives at the second mobile device; With a time difference between Further equipped with determining a location of the first mobile device is further based on the first time difference and the second time difference, and optionally, the first wireless reference signal and the third wireless reference signal comprise the same signal, or the first wireless reference signal and the third wireless reference signal comprise different signals, and determining a location of the first mobile device is further based on a time difference between transmission of the first wireless reference signal and transmission of the third wireless reference signal. The method of claim 1.

13. 1. A device for enabling low power positioning of a first mobile device using differential angle of arrival (AoA), comprising: A transceiver; Memory, one or more processing units communicatively coupled to the transceiver and the memory; wherein the one or more processing units: obtaining, via the transceiver, a differential AoA between a first AoA of a first wireless reference signal at a second mobile device and a second AoA of a second wireless reference signal at the second mobile device, wherein: the first wireless reference signal is transmitted by a first wireless network node; the second wireless reference signal being transmitted by the first mobile device; determining a location of the first mobile device based at least in part on the differential AoA; and Providing a location of the first mobile device; and A device configured to:

14. The device of claim 13, further comprising means for performing a method according to any one of claims 2 to 12.

15. 1. A non-transitory computer-readable medium having stored thereon instructions for enabling low power positioning of a first mobile device using differential angle of arrival (AoA), the instructions comprising: code for obtaining a differential AoA between a first AoA of a first wireless reference signal at a second mobile device and a second AoA of a second wireless reference signal at the second mobile device, wherein: the first wireless reference signal is transmitted by a wireless network node; the second wireless reference signal being transmitted by the first mobile device; code for determining a location of the first mobile device based at least in part on the differential AoA; and code for providing a location of the first mobile device; 1. A non-transitory computer-readable medium comprising:

Images