UE passive RF sensing with cellular-based bistatic/multistatic radar

Techniques are disclosed for determining the location of an object using RF sensing. More specifically, an object may be detected in a wireless data communication network using radar techniques in which one or more base stations act as a transmitter and a mobile device (e.g., a user equipment (UE)) acts as a receiver in a bistatic or multi-static radar configuration. By comparing the time a line-of-sight (LOS) signal is received by the mobile device with that of an echo signal from a reflection of an RF signal from the object, a position of the object can be determined. Depending on desired functionality, this position can be determined by the UE, or by a network entity.

BACKGROUND

1. Field of Invention

The present invention relates generally to the field of wireless communications, and more specifically to determining the location or position of an object with radiofrequency (RF) signals using bistatic or multi-static radar techniques.

2. Description of Related Art

In a wireless communication network, RF sensing techniques can be used to determine the position of an object. Some of these positioning techniques may involve determining distance and/or angular information of RF signals transmitted by one or more base stations of the wireless communication network. These determinations, however, typically require active communications between a mobile device base stations. As such, position determination in a wireless communication network of objects that do not communicate with base stations has been limited.

An example of performing radio frequency (RF) sensing with a mobile device in a wireless communications network, according to this disclosure, comprises receiving, at the mobile device, a configuration from a server, where the configuration includes timing information for each of one or more wireless reference signals transmitted by a network entity of the wireless communications network. The method also comprises determining, with the mobile device and based on the configuration: a first time of arrival (TOA) of a line-of-sight (LOS) wireless signal at the mobile device, where the LOS wireless signal may comprise a first wireless reference signal of the one or more wireless reference signals; and a second TOA of an echo signal at the mobile device, where the echo signal may comprise a reflection, from an object, of the first wireless reference signal or a second wireless reference signal of the one or more wireless reference signals. The method also comprises determining, with the mobile device, a position of the mobile device relative to the network entity. The method also comprises determining, with the mobile device, a position of the object based on: a time difference between the first TOA and the second TOA, and the position of the mobile device relative to the network entity. The method also comprises providing the position of the object with the mobile device.

An example method of performing radio frequency (RF) sensing with a mobile device in a wireless communications network, according to this disclosure, comprises receiving, by the mobile device, a request from a server to conduct RF sensing. The method also comprises subsequent to receiving the request, receiving, at the mobile device, a configuration from a server, where the configuration includes timing information for each of one or more wireless reference signals transmitted by a network entity of the wireless communications network. The method also comprises determining, with the mobile device and based on the configuration: a first time of arrival (TOA) of a line-of-sight (LOS) wireless signal at the mobile device, where the LOS wireless signal may comprise a first wireless reference signal of the one or more wireless reference signals; and a second TOA of an echo signal at the mobile device, where the echo signal may comprise a reflection, from an object, of the first wireless reference signal or a second wireless reference signal of the one or more wireless reference signals. The method also comprises sending, from the mobile device to the server, information indicative of a time difference between the first TOA and the second TOA.

An example method of performing radio frequency (RF) sensing of an object in a wireless communications network, according to this disclosure, comprises sending a configuration from a server to a mobile device, where the configuration includes timing information for each of one or more wireless reference signals transmitted by a network entity of the wireless communications network. The method also comprises subsequent to sending the configuration, receiving, with the server, information indicative of a time difference between a first time of arrival (TOA) and a second TOA, where: the first TOA may comprise a TOA of a line-of-sight (LOS) wireless signal at the mobile device, where the LOS wireless signal may comprise a first wireless reference signal of the one or more wireless reference signals; and the second TOA may comprise a TOA of an echo signal at the mobile device, where the echo signal may comprise a reflection, from the object, of the first wireless reference signal or a second wireless reference signal of the one or more wireless reference signals. The method also comprises determining, with the server, a position of the mobile device relative to the network entity. The method also comprises determining, with the server, the position of the object based on: a time difference between the first TOA and the second TOA, and the position of the mobile device relative to the network entity. The method also comprises sending the position of the object to a device.

An example mobile device, according to this disclosure, comprises a wireless communication interface, a memory, and one or more processing units communicatively coupled with the wireless communication interface and the memory. The one or more processing units are configured to receive, via the wireless communication interface, a configuration from a server, where the configuration includes timing information for each of one or more wireless reference signals transmitted by a network entity of a wireless communications network; determine, based on the configuration: a first time of arrival (TOA) of a line-of-sight (LOS) wireless signal at the mobile device, where the LOS wireless signal may comprise a first wireless reference signal of the one or more wireless reference signals; and a second TOA of an echo signal at the mobile device, where the echo signal may comprise a reflection, from an object, of the first wireless reference signal or a second wireless reference signal of the one or more wireless reference signals. The one or more processing units are also configured to: determine a position of the mobile device relative to the network entity; determine a position of the object based on: a time difference between the first TOA and the second TOA, and the position of the mobile device relative to the network entity. The one or more processing units are also configured to provide the position of the object with the mobile device.

Another example mobile device, according to this disclosure, comprises a wireless communication interface, a memory, and one or more processing units communicatively coupled with the wireless communication interface and the memory. The one or more processing units are configured to receive, via the wireless communication interface, a request from a server to conduct radio frequency (RF) sensing. The one or more processing units are also configured to receive, via the wireless communication interface and subsequent to receiving the request, a configuration from a server, where the configuration includes timing information for each of one or more wireless reference signals transmitted by a network entity of a wireless communications network. The one or more processing units are also configured to determine, based on the configuration: a first time of arrival (TOA) of a line-of-sight (LOS) wireless signal at the mobile device, where the LOS wireless signal may comprise a first wireless reference signal of the one or more wireless reference signals; and a second TOA of an echo signal at the mobile device, where the echo signal may comprise a reflection, from an object, of the first wireless reference signal or a second wireless reference signal of the one or more wireless reference signals. The one or more processing units are also configured to send, to the server via the wireless communication interface, information indicative of a time difference between the first TOA and the second TOA.

An example server, according to this disclosure, comprises a communication interface, a memory, and one or more processing units communicatively coupled with the communication interface and the memory. The one or more processing units are configured to send, via the communication interface, a configuration to a mobile device, where the configuration includes timing information for each of one or more wireless reference signals transmitted by a network entity of a wireless communications network; subsequent to sending the configuration, receive, via the communication interface, information indicative of a time difference between a first time of arrival (TOA) and a second TOA, where: the first TOA may comprise a TOA of a line-of-sight (LOS) wireless signal at the mobile device, where the LOS wireless signal may comprise a first wireless reference signal of the one or more wireless reference signals; and the second TOA may comprise a TOA of an echo signal at the mobile device, where the echo signal may comprise a reflection, from an object, of the first wireless reference signal or a second wireless reference signal of the one or more wireless reference signals. The one or more processing units are also configured to determine a position of the mobile device relative to the network entity; determine the position of the object based on: a time difference between the first TOA and the second TOA, and the position of the mobile device relative to the network entity. The one or more processing units are also configured to send, via the communication interface, the position of the object to a device.

An example device, according to this disclosure, comprises means for receiving a configuration from a server, where the configuration includes timing information for each of one or more wireless reference signals transmitted by a network entity of a wireless communications network. The device also comprises means for determining, based on the configuration: a first time of arrival (TOA) of a line-of-sight (LOS) wireless signal at the device, where the LOS wireless signal may comprise a first wireless reference signal of the one or more wireless reference signals; and a second TOA of an echo signal at the device, where the echo signal may comprise a reflection, from an object, of the first wireless reference signal or a second wireless reference signal of the one or more wireless reference signals. The device also comprises means for determining a position of the device relative to the network entity. The device also comprises means for determining a position of the object based on: a time difference between the first TOA and the second TOA, and the position of the device relative to the network entity. The device also comprises means for providing the position of the object with the device.

Another example device, according to this disclosure, comprises means for receiving a request from a server to conduct radio frequency (RF) sensing. The device also comprises means for receiving, subsequent to receiving the request, a configuration from a server, where the configuration includes timing information for each of one or more wireless reference signals transmitted by a network entity of a wireless communications network. The device also comprises means for determining, with the device and based on the configuration: a first time of arrival (TOA) of a line-of-sight (LOS) wireless signal at the device, where the LOS wireless signal may comprise a first wireless reference signal of the one or more wireless reference signals; and a second TOA of an echo signal at the device, where the echo signal may comprise a reflection, from an object, of the first wireless reference signal or a second wireless reference signal of the one or more wireless reference signals. The device also comprises means for sending, from the device to the server, information indicative of a time difference between the first TOA and the second TOA.

Yet another example device, according to this disclosure, comprises means for sending a configuration from a device to a mobile device, where the configuration includes timing information for each of one or more wireless reference signals transmitted by a network entity of a wireless communications network. The device also comprises means for receiving, subsequent to sending the configuration, information indicative of a time difference between a first time of arrival (TOA) and a second TOA, where: the first TOA may comprise a TOA of a line-of-sight (LOS) wireless signal at the mobile device, where the LOS wireless signal may comprise a first wireless reference signal of the one or more wireless reference signals; and the second TOA may comprise a TOA of an echo signal at the mobile device, where the echo signal may comprise a reflection, from an object, of the first wireless reference signal or a second wireless reference signal of the one or more wireless reference signals. The device also comprises means for determining a position of the mobile device relative to the network entity. The device also comprises means for determining the position of the object based on: a time difference between the first TOA and the second TOA, and the position of the mobile device relative to the network entity. The device also comprises means for sending the position of the object to a device.

An example non-transitory computer-readable medium, according to this disclosure, comprises a storing instructions for performing radio frequency (RF) sensing with a mobile device in a wireless communications network. The instructions comprise code for receiving a configuration from a server, where the configuration includes timing information for each of one or more wireless reference signals transmitted by a network entity of the wireless communications network. The instructions also comprise code for determining, based on the configuration: a first time of arrival (TOA) of a line-of-sight (LOS) wireless signal at the mobile device, where the LOS wireless signal may comprise a first wireless reference signal of the one or more wireless reference signals; and a second TOA of an echo signal at the mobile device, where the echo signal may comprise a reflection, from an object, of the first wireless reference signal or a second wireless reference signal of the one or more wireless reference signals. The instructions also comprise code for determining a position of the mobile device relative to the network entity. The instructions also comprise code for determining a position of the object based on: a time difference between the first TOA and the second TOA, and the position of the mobile device relative to the network entity. The instructions also comprise code for providing the position of the object with the mobile device.

An example non-transitory computer-readable medium, according to this disclosure, stores instructions for performing radio frequency (RF) sensing with a mobile device in a wireless communications network. The instructions comprise code for receiving, by the mobile device, a request from a server to conduct RF sensing. The instructions also comprise code for, subsequent to receiving the request, receiving, at the mobile device, a configuration from a server, where the configuration includes timing information for each of one or more wireless reference signals transmitted by a network entity of the wireless communications network. The instructions also comprise code for determining, based on the configuration: a first time of arrival (TOA) of a line-of-sight (LOS) wireless signal at the mobile device, where the LOS wireless signal may comprise a first wireless reference signal of the one or more wireless reference signals; and a second TOA of an echo signal at the mobile device, where the echo signal may comprise a reflection, from an object, of the first wireless reference signal or a second wireless reference signal of the one or more wireless reference signals. The instructions also comprise code for sending, from the mobile device to the server, information indicative of a time difference between the first TOA and the second TOA.

An example non-transitory computer-readable medium, according to this disclosure, stores instructions for performing radio frequency (RF) sensing of an object in a wireless communications network. The instructions comprise code for sending a configuration from a server to a mobile device, where the configuration includes timing information for each of one or more wireless reference signals transmitted by a network entity of the wireless communications network. The instructions also comprise code for, subsequent to sending the configuration, receiving, with the server, information indicative of a time difference between a first time of arrival (TOA) and a second TOA, where: the first TOA may comprise a TOA of a line-of-sight (LOS) wireless signal at the mobile device, where the LOS wireless signal may comprise a first wireless reference signal of the one or more wireless reference signals; and the second TOA may comprise a TOA of an echo signal at the mobile device, where the echo signal may comprise a reflection, from the object, of the first wireless reference signal or a second wireless reference signal of the one or more wireless reference signals. The instructions also comprise code for determining a position of the mobile device relative to the network entity. The instructions also comprise code for determining the position of the object based on: a time difference between the first TOA and the second TOA, and the position of the mobile device relative to the network entity. The instructions also comprise code for sending the position of the object to a device.

BRIEF SUMMARY

Embodiments described herein provide for the determination of the location of an object using RF sensing. More specifically, an object may be detected in a wireless data communication network using radar techniques in which one or more base stations act as a transmitter and a mobile device (e.g., UE) acts as a receiver in a bistatic or multi-static radar configuration. By comparing the time a line-of-sight (LOS) signal is received by the mobile device with that of an echo signal from a reflection of an RF signal from the object, a position of the object can be determined. Depending on desired functionality, this position can be determined by the UE, or by a network entity.

Like reference symbols in the various drawings indicate like elements, in accordance with certain example implementations. In addition, multiple instances of an element may be indicated by following a first number for the element with a letter or a hyphen and a second number. For example, multiple instances of an element110may be indicated as110-1,110-2,110-3etc. or as110a,110b,110c, etc. When referring to such an element using only the first number, any instance of the element is to be understood (e.g., element110in the previous example would refer to elements110-1,110-2, and110-3or to elements110a,110b, and110c).

DETAILED DESCRIPTION

Several illustrative embodiments will now be described with respect to the accompanying drawings, which form a part hereof. While some embodiments in which one or more aspects of the disclosure may be implemented as described below, other embodiments may be used, and various modifications may be made without departing from the scope of the disclosure.

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

FIG.1is a simplified illustration of a positioning system100in which a UE105, location server160, and/or other components of the positioning system100can use the techniques provided herein for performing passive RF sensing as described herein, according to an embodiment. It can be noted, however, that techniques described herein are not necessarily limited to a positioning system100. The techniques described herein may be implemented by one or more components of the positioning system100. The positioning system100can include a UE105, one or more satellites110(also referred to as space vehicles (SVs)) for a Global Navigation Satellite System (GNSS) such as the Global Positioning System (GPS), base stations120, access points (APs)130, location server160, network170, and external client180. Generally put, the positioning system100can estimate location of the UE105based on RF signals received by and/or sent from the UE105and known locations of other components (e.g., GNSS satellites110, base stations120, APs130) transmitting and/or receiving the RF signals. Additional details regarding particular location estimation techniques are discussed in more detail with regard toFIG.2.

It should be noted thatFIG.1provides only a generalized illustration of various components, any or all of which may be utilized as appropriate, and each of which may be duplicated as necessary. Specifically, although only one UE105is illustrated, it will be understood that many UEs (e.g., hundreds, thousands, millions, etc.) may utilize the positioning system100. Similarly, the positioning system100may include a larger or smaller number of base stations120and/or APs130than illustrated inFIG.1. The illustrated connections that connect the various components in the positioning system100comprise data and signaling connections which may include additional (intermediary) 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 desired functionality. In some embodiments, for example, the external client180may be directly connected to location server160. A person of ordinary skill in the art will recognize many modifications to the components illustrated.

Depending on desired functionality, the network170may comprise any of a variety of wireless and/or wireline networks. The network170can, for example, comprise any combination of public and/or private networks, local and/or wide-area networks, and the like. Furthermore, the network170may utilize one or more wired and/or wireless communication technologies. In some embodiments, the network170may comprise a cellular or other mobile network, a wireless local area network (WLAN), a wireless wide-area network (WWAN), and/or the Internet, for example. Examples of network170include a Long-Term Evolution (LTE) wireless network, a Fifth Generation (5G) wireless network (also referred to as New Radio (NR) wireless network or 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). Network170may also include more than one network and/or more than one type of network.

The base stations120and access points (APs)130are communicatively coupled to the network170. In some embodiments, the base station120smay 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 network170, a base station120may comprise a node B, an Evolved Node B (eNodeB or eNB), a base transceiver station (BTS), a radio base station (RBS), an NR NodeB (gNB), a Next Generation eNB (ng-eNB), or the like. A base station120that is a gNB or ng-eNB may be part of a Next Generation Radio Access Network (NG-RAN) which may connect to a 5G Core Network (5GC) in the case that Network170is a 5G network. An AP130may comprise a Wi-Fi AP or a Bluetooth® AP, for example. Thus, UE105can send and receive information with network-connected devices, such as location server160, by accessing the network170via a base station120using a first communication link133. Additionally or alternatively, because APs130also may be communicatively coupled with the network170, UE105may communicate with Internet-connected devices, including location server160, using a second communication link135.

As used herein, the term “base station” may generically refer to a single physical transmission point, or multiple co-located physical transmission points, which may be located at a base station120. A Transmission Reception Point (TRP) (also known as transmit/receive point) corresponds to this type of transmission point, and the term “TRP” may be used interchangeably herein with the terms “gNB,” “ng-eNB,” and “base station.” Physical transmission points may comprise an array of antennas (e.g., as in a Multiple Input-Multiple Output (MIMO) system and/or where the base station employs beamforming) of the base station. The term “base station” may additionally refer to multiple non-co-located physical transmission points, the physical transmission points 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). Alternatively, the non-co-located physical transmission points may be the serving base station receiving the measurement report from the UE105and a neighbor base station whose reference RF signals the UE105is measuring.

The location server160may comprise a server and/or other computing device configured to determine an estimated location of UE105and/or provide data (e.g., “assistance data”) to UE105to facilitate the location determination. According to some embodiments, location server160may comprise a Home Secure User Plane Location (SUPL) Location Platform (H-SLP), which may support the SUPL user plane (UP) location solution defined by the Open Mobile Alliance (OMA) and may support location services for UE105based on subscription information for UE105stored in location server160. In some embodiments, the location server160may comprise, a Discovered SLP (D-SLP) or an Emergency SLP (E-SLP). The location server160may also comprise an Enhanced Serving Mobile Location Center (E-SMLC) that supports location of UE105using a control plane (CP) location solution for LTE radio access by UE105. The location server160may further comprise a Location Management Function (LMF) that supports location of UE105using a control plane (CP) location solution for NR radio access by UE105. In a CP location solution, signaling to control and manage the location of UE105may be exchanged between elements of network170and with UE105using existing network interfaces and protocols and as signaling from the perspective of network170. In a UP location solution, signaling to control and manage the location of UE105may be exchanged between location server160and UE105as data (e.g. data transported using the Internet Protocol (IP) and/or Transmission Control Protocol (TCP)) from the perspective of network170.

As previously noted (and discussed in more detail below), the estimated location of UE105may be based on measurements of RF signals sent from and/or received by the UE105. In particular, these measurements can provide information regarding the relative distance and/or angle of the UE105from one or more components in the positioning system100(e.g., GNSS satellites110, APs130, base stations120). The estimated location of the UE105can be estimated geometrically (e.g., using multiangulation and/or multilateration), based on the distance and/or angle measurements, along with known position of the one or more components.

Although terrestrial components such as APs130and base stations120may be fixed, embodiments are not so limited. Mobile components may be used. Moreover, in some embodiments, location of the UE105estimated at least in part based on measurements of RF signals communicated between the UE105and one or more other UEs (not shown inFIG.1), which may be mobile. Direct communication between UEs in this manner may comprise sidelink and/or similar Device-to-Device (D2D) communication technologies. Sidelink, which is defined by 3GPP, is a form of D2D communication under the cellular-based LTE and NR standards.

An estimated location of UE105can be used in a variety of applications—e.g. to assist direction finding or navigation for a user of UE105or to assist another user (e.g. associated with external client180) to locate UE105. A “location” is also referred to herein as a “location estimate”, “estimated location”, “location”, “position”, “position estimate”, “position fix”, “estimated position”, “location fix” or “fix”. A location of UE105may comprise an absolute location of UE105(e.g. a latitude and longitude and possibly altitude) or a relative location of UE105(e.g. a location expressed as distances north or south, east or west and possibly above or below some other known fixed location or some other location such as a location for UE105at some known previous time). A location may also be specified as a geodetic location (as a latitude and longitude) or as a civic location (e.g. in terms of a street address or using other location related names and labels). A location may further include an uncertainty or error indication, such as a horizontal and possibly vertical distance by which the location is expected to be in error or an indication of an area or volume (e.g. a circle or ellipse) within which UE105is expected to be located with some level of confidence (e.g. 95% confidence).

The external client180may be a web server or remote application that may have some association with UE105(e.g. may be accessed by a user of UE105) or may be a server, application, or computer system providing a location service to some other user or users which may include obtaining and providing the location of UE105(e.g. to enable a service such as friend or relative finder, asset tracking or child or pet location). Additionally or alternatively, the external client180may obtain and provide the location of UE105to an emergency services provider, government agency, etc.

As previously noted, the example positioning system100can be implemented using a wireless communication network, such as an LTE-based or 5G NR-based network. 5G NR is a wireless RF interface undergoing standardization by the 3rd Generation Partnership Project (3GPP). 5G NR is poised to offer enhanced functionality over previous generation (LTE) technologies, such as significantly faster and more responsive mobile broadband, enhanced conductivity through Internet of Things (IoT) devices, and more. Additionally, 5G NR enables new positioning techniques for UEs, including Angle of Arrival (AoA)/Angle of Departure (AoD) positioning, UE-based positioning, and multi-cell Round Trip signal propagation Time (RTT) positioning. With regard to RTT positioning, this involves taking RTT measurements between the UE and multiple base stations.

FIG.2shows a diagram of a 5G NR positioning system200, illustrating an embodiment of a positioning system (e.g., positioning system100) implementing 5G NR. The 5G NR positioning system200may be configured to determine the location of a UE105by using access nodes210,214,216(which may correspond with base stations120and access points130ofFIG.1) and (optionally) an LMF220(which may correspond with location server160) to implement one or more positioning methods. Here, the 5G NR positioning system200comprises a UE105, and components 5G NR network comprising a Next Generation (NG) Radio Access Network (RAN) (NG-RAN)235and a 5G Core Network (5G CN)240. A 5G network may also be referred to as an NR network; NG-RAN235may be referred to as a 5G RAN or as an NR RAN; and 5G CN240may be referred to as an NG Core network. Standardization of an NG-RAN and 5G CN is ongoing in 3GPP. Accordingly, NG-RAN235and 5G CN240may conform to current or future standards for 5G support from 3GPP. The 5G NR positioning system200may further utilize information from GNSS satellites110from a GNSS system like Global Positioning System (GPS) or similar system. Additional components of the 5G NR positioning system200are described below. The 5G NR positioning system200may include additional or alternative components.

It should be noted thatFIG.2provides only a generalized illustration of various components, any or all of which may be utilized as appropriate, and each of which may be duplicated or omitted as necessary. Specifically, although only one UE105is illustrated, it will be understood that many UEs (e.g., hundreds, thousands, millions, etc.) may utilize the 5G NR positioning system200. Similarly, the 5G NR positioning system200may include a larger (or smaller) number of GNSS satellites110, gNBs210, ng-eNBs214, Wireless Local Area Networks (WLANs)216, Access and Mobility Functions (AMF)s215, external clients230, and/or other components. The illustrated connections that connect the various components in the 5G NR positioning system200include data and signaling connections which may include additional (intermediary) 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 desired functionality.

The UE105may 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, UE105may correspond to a cellphone, smartphone, laptop, tablet, personal data assistant (PDA), tracking device, navigation device, Internet of Things (IoT) device, or some other portable or moveable device. Typically, though not necessarily, the UE105may support wireless communication using one or more Radio Access Technologies (RATs) such as using Global System for Mobile Communications (GSM), Code Division Multiple Access (CDMA), Wideband CDMA (WCDMA), Long-Term Evolution (LTE), High Rate Packet Data (HRPD), IEEE 802.11 Wi-Fi®, Bluetooth, Worldwide Interoperability for Microwave Access (WiMAX™), 5G NR (e.g., using the NG-RAN235and 5G CN240), etc. The UE105may also support wireless communication using a WLAN216which (like the one or more RATs, and as previously noted with respect toFIG.1) may connect to other networks, such as the Internet. The use of one or more of these RATs may allow the UE105to communicate with an external client230(e.g., via elements of 5G CN240not shown inFIG.2, or possibly via a Gateway Mobile Location Center (GMLC)225) and/or allow the external client230to receive location information regarding the UE105(e.g., via the GMLC225).

Base stations in the NG-RAN235shown inFIG.2may correspond to base stations120inFIG.1and may include NR NodeB (gNB)210-1and210-2(collectively and generically referred to herein as gNBs210) and/or an antenna of a gNB. Pairs of gNBs210in NG-RAN235may be connected to one another (e.g., directly as shown inFIG.2or indirectly via other gNBs210). Access to the 5G network is provided to UE105via wireless communication between the UE105and one or more of the gNBs210, which may provide wireless communications access to the 5G CN240on behalf of the UE105using 5G NR. 5G NR radio access may also be referred to as NR radio access or as 5G radio access. InFIG.2, the serving gNB for UE105is assumed to be gNB210-1, although other gNBs (e.g. gNB210-2) may act as a serving gNB if UE105moves to another location or may act as a secondary gNB to provide additional throughput and bandwidth to UE105.

Base stations in the NG-RAN235shown inFIG.2may also or instead include a next generation evolved Node B, also referred to as an ng-eNB,214. Ng-eNB214may be connected to one or more gNBs210in NG-RAN235—e.g. directly or indirectly via other gNBs210and/or other ng-eNBs. An ng-eNB214may provide LTE wireless access and/or evolved LTE (eLTE) wireless access to UE105. Some gNBs210(e.g. gNB210-2) and/or ng-eNB214inFIG.2may be configured to function as positioning-only beacons which may transmit signals (e.g., Positioning Reference Signal (PRS)) and/or may broadcast assistance data to assist positioning of UE105but may not receive signals from UE105or from other UEs. It is noted that while only one ng-eNB214is shown inFIG.2, some embodiments may include multiple ng-eNBs214. Base stations210,214may communicate directly with one another via an Xn communication interface. Additionally or alternatively, base stations210,214may communicate indirectly via another component of the 5G NR positioning system200, such as the LMF220.

5G NR positioning system200may also include one or more WLANs216which may connect to a Non-3GPP InterWorking Function (N3IWF)250in the 5G CN240(e.g., in the case of an untrusted WLAN216). For example, the WLAN216may support IEEE 802.11 Wi-Fi access for UE105and may comprise one or more Wi-Fi APs (e.g., APs130ofFIG.1). Here, the N3IWF250may connect to other elements in the 5G CN240such as AMF215. In some embodiments, WLAN216may support another RAT such as Bluetooth. The N3IWF250may provide support for secure access by UE105to other elements in 5G CN240and/or may support interworking of one or more protocols used by WLAN216and UE105to one or more protocols used by other elements of 5G CN240such as AMF215. For example, N3IWF250may support IPSec tunnel establishment with UE105, termination of IKEv2/IPSec protocols with UE105, termination of N2 and N3 interfaces to 5G CN240for control plane and user plane, respectively, relaying of uplink and downlink control plane Non-Access Stratum (NAS) signaling between UE105and AMF215across an N1 interface. In some other embodiments, WLAN216may connect directly to elements in 5G CN240(e.g. AMF215as shown by the dashed line inFIG.2) and not via N3IWF250—e.g. if WLAN216is a trusted WLAN for 5G CN240. It is noted that while only one WLAN216is shown inFIG.2, some embodiments may include multiple WLANs216.

Access nodes may comprise any of a variety of network entities enabling communication between the UE105and the AMF215. This can include gNBs210, ng-eNB214, WLAN216, and/or other types of cellular base stations. However, access nodes providing the functionality described herein may additionally or alternatively include entities enabling communications to any of a variety of RATs not illustrated inFIG.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 gNB210, ng-eNB214or WLAN216.

In some embodiments, an access node, such as a gNB210, ng-eNB214, or WLAN216(alone or in combination with other components of the 5G NR positioning system200), may be configured to, in response to receiving a request for location information for multiple RATs from the LMF220, take measurements for one of the multiple RATs (e.g., measurements of the UE105) and/or obtain measurements from the UE105that are transferred to the access node using one or more of the multiple RATs. As noted, whileFIG.2depicts access nodes210,214, and216configured 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 a Bluetooth® beacon using a Bluetooth protocol for a WLAN. For example, in a 4G Evolved Packet System (EPS) providing LTE wireless access to UE105, a RAN may comprise an E-UTRAN, which may comprise base stations comprising eNBs supporting LTE wireless access. A core network for EPS may comprise an Evolved Packet Core (EPC). An EPS may then comprise an E-UTRAN plus an EPC, where the E-UTRAN corresponds to NG-RAN235and the EPC corresponds to 5G CN240inFIG.2. The methods and techniques described herein for UE105positioning using common or generic positioning procedures may be applicable to such other networks.

The gNBs210and ng-eNB214can communicate with an AMF215, which, for positioning functionality, communicates with an LMF220. The AMF215may support mobility of the UE105, including cell change and handover of UE105from an access node210,214, or216of a first RAT to an access node210,214, or216of a second RAT. The AMF215may also participate in supporting a signaling connection to the UE105and possibly data and voice bearers for the UE105. The LMF220may support positioning of the UE105when UE105accesses the NG-RAN235or WLAN216and may support position procedures and methods, including UE assisted/UE based and/or network based procedures/methods, such as Assisted GNSS (A-GNSS), Observed Time Difference Of Arrival (OTDOA) (which may be referred to in NR as Time Difference Of Arrival (TDOA)), Real Time Kinematics (RTK), Precise Point Positioning (PPP), Differential GNSS (DGNSS), ECID, angle of arrival (AoA), angle of departure (AoD), WLAN positioning, and/or other positioning procedures and methods. The LMF220may also process location services requests for the UE105, e.g., received from the AMF215or from the GMLC225. The LMF220may be connected to AMF215and/or to GMLC225. The LMF220may be referred to by other names such as a Location Manager (LM), Location Function (LF), commercial LMF (CLMF), or value added LMF (VLMF). In some embodiments, a node/system that implements the LMF220may additionally or alternatively implement other types of location-support modules, such as an Evolved Serving Mobile Location Center (E-SMLC) or Service Location Protocol (SLP). It is noted that in some embodiments, at least part of the positioning functionality (including determination of a UE's location) may be performed at the UE105(e.g., by processing downlink PRS (DL-PRS) signals transmitted by wireless nodes such as gNBs210, ng-eNB214and/or WLAN216, and/or using assistance data provided to the UE105, e.g., by LMF220).

The Gateway Mobile Location Center (GMLC)225may support a location request for the UE105received from an external client230and may forward such a location request to the AMF215for forwarding by the AMF215to the LMF220or may forward the location request directly to the LMF220. A location response from the LMF220(e.g., containing a location estimate for the UE105) may be similarly returned to the GMLC225either directly or via the AMF215, and the GMLC225may then return the location response (e.g., containing the location estimate) to the external client230. The GMLC225is shown connected to both the AMF215and LMF220inFIG.2though only one of these connections may be supported by 5G CN240in some implementations.

As further illustrated inFIG.2, the LMF220may communicate with the gNBs210and/or with the ng-eNB214using the LPPa protocol (which also may be referred to as NRPPa or NPPa). LPPa protocol in NR may be the same as, similar to, or an extension of the LPPa protocol in LTE (related to LTE Positioning Protocol (LPP)), with LPPa messages being transferred between a gNB210and the LMF220, and/or between an ng-eNB214and the LMF220, via the AMF215. As further illustrated inFIG.2, LMF220and UE105may communicate using the LPP protocol. LMF220and UE105may also or instead communicate using an LPP protocol (which, in NR, also may be referred to as NRPP or NPP). Here, LPP messages may be transferred between the UE105and the LMF220via the AMF215and a serving gNB210-1or serving ng-eNB214for UE105. For example, LPP and/or LPP messages may be transferred between the LMF220and the AMF215using messages for service-based operations (e.g., based on the Hypertext Transfer Protocol (HTTP)) and may be transferred between the AMF215and the UE105using a 5G NAS protocol. The LPP and/or LPP protocol may be used to support positioning of UE105using UE assisted and/or UE based position methods such as A-GNSS, RTK, OTDOA and/or Enhanced Cell ID (ECID). The LPPa protocol may be used to support positioning of UE105using network based position methods such as ECID (e.g., when used with measurements obtained by a gNB210or ng-eNB214) and/or may be used by LMF220to obtain location related information from gNBs210and/or ng-eNB214, such as parameters defining DL-PRS transmission from gNBs210and/or ng-eNB214.

In the case of UE105access to WLAN216, LMF220may use LPPa and/or LPP to obtain a location of UE105in a similar manner to that just described for UE105access to a gNB210or ng-eNB214. Thus, LPPa messages may be transferred between a WLAN216and the LMF220, via the AMF215and N3IWF250to support network-based positioning of UE105and/or transfer of other location information from WLAN216to LMF220. Alternatively, LPPa messages may be transferred between N3IWF250and the LMF220, via the AMF215, to support network-based positioning of UE105based on location related information and/or location measurements known to or accessible to N3IWF250and transferred from N3IWF250to LMF220using LPPa. Similarly, LPP and/or LPP messages may be transferred between the UE105and the LMF220via the AMF215, N3IWF250, and serving WLAN216for UE105to support UE assisted or UE based positioning of UE105by LMF220.

With a UE-assisted position method, UE105may obtain location measurements and send the measurements to a location server (e.g., LMF220) for computation of a location estimate for UE105. Location measurements may include one or more of a Received Signal Strength Indication (RSSI), RTT, Reference Signal Receive Power (RSRP), Reference Signal Received Quality (RSRQ), Time of Arrival (ToA), AoA, Differential AoA (DAoA), AoD, or Timing Advance (TA) for gNBs210, ng-eNB214, and/or one or more access points for WLAN216. 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 for GNSS satellites110), WLAN, etc. With a UE-based position method, UE105may obtain location measurements (e.g., which may be the same as or similar to location measurements for a UE assisted position method) and may further compute a location of UE105(e.g., with the help of assistance data received from a location server such as LMF220or broadcast by gNBs210, ng-eNB214, or WLAN216). With a network based position method, one or more base stations (e.g., gNBs210and/or ng-eNB214), one or more APs (e.g., in WLAN216), or N3IWF250may obtain location measurements (e.g., measurements of RSSI, RTT, RSRP, RSRQ, AoA, or ToA) for signals transmitted by UE105, and/or may receive measurements obtained by UE105or by an AP in WLAN216in the case of N3IWF250, and may send the measurements to a location server (e.g., LMF220) for computation of a location estimate for UE105.

In a 5G NR positioning system200, some location measurements taken by the UE105(e.g., AoA, AoD, ToA) may use RF reference signals received from base stations210and214. These signals may comprise PRS, which can be used, for example, to execute OTDOA, AoD, and RTT-based positioning of the UE105. Other reference signals that can be used for positioning may include Cell-specific Reference Signal (CRS), Channel State Information Reference Signal (CSI-RS), synchronization signals (e.g., synchronization signal block (SSB) Synchronizations Signal (SS)), etc. Moreover, the signals may be transmitted in a Tx beam (e.g., using beamforming techniques), which may impact angular measurements, such as AoD.

FIG.3is a diagram illustrating a simplified environment300including two base stations120-1and120-2(which may correspond to base stations120ofFIG.1and/or gNBs210and/or ng-eNB214ofFIG.2) producing directional beams for transmitting RF reference signals, and a UE105. Each of the directional beams is rotated, e.g., through 120 or 360 degrees, for each beam sweep, which may be periodically repeated. Each direction beam can include an RF reference signal (e.g., a PRS resource), where base station120-1produces a set of RF reference signals that includes Tx beams305-a,305-b,305-c,305-d,305-e,305-f,305-g, and305-h, and the base station120-2produces a set of RF reference signals that includes Tx beams309-a,309-b,309-c,309-d,309-e,309-f,309-g, and309-h. Because UE105may also include an antenna array, it can receive RF reference signals transmitted by base stations120-1and120-2using beamforming to form respective receive beams (Rx beams)311-aand311-b. Beamforming in this manner (by base stations120and optionally by UEs105) can be used to make communications more efficient. It can also be used for other purposes, such as transmitting reference signals for RF sensing of an object. (An object detected using the radar techniques described herein is also referred to herein as a “target.”)

As previously noted, network-based positioning of a target traditionally requires measurements and/or communications by the target. RTT-based positioning, for example, requires a target to transmit and receive signals. AoD-based positioning requires a target to make a RSRP measurement for AoD determination. As such, network-based positioning was traditionally limited to a UE105, which is capable of taking measurements and communicating with base stations.

Embodiments described herein provide for determining the location of a target using RF sensing in a wireless communication network, in which one or more base stations can act as a transmitter and one or more UEs can as a receiver in a bistatic or multi-static radar configuration. By comparing the time a line-of-sight (LOS) signal is received by a UE with that of an echo signal from a reflection of an RF signal from the target, a position of the target can be determined. Depending on desired functionality, this position can be determined by the UE, or by a network entity.FIG.4helps illustrated how this is accomplished.

FIG.4is a simplified diagram illustrating how RF sensing can be used to determine the position of a target410, according to an embodiment. Here, RF sensing is performed using a bistatic radar configuration, where the base station120(which may comprise a serving base station for the UE105) performs the function of a radar transmitter and the UE105performs the function of a radar receiver. Here, positioning of the target410is accomplished by transmitting one or more reference signals450,460from a base station120, receiving an LOS reference signal460and echo signal470at the UE105, and calculating the position of the target410based on a difference in time at which these signals are received at the UE105, along with known positions of the UE105and base station120. This process may be facilitated with the use of a location server160. As discussed in more detail below, the UE105or location server160may determine the position of the target410, depending on desired functionality.

It can be noted that, although a bistatic configuration is illustrated inFIG.4, embodiments are not so limited. According to some embodiments, multi-static configurations may be used in which there are a plurality of base stations120(transmitters) and/or a plurality of UEs105(receivers). In such configurations, a position of the target410can be determined as described herein for each transmitter/receiver pair, then determinations for all transmitter/receiver pairs can be combined. In such configurations, this can increase accuracy and/or reliability of position determination of the target410.

The position of the target410can be determined mathematically by solving for the distance, RR, of the target410from t UE105, as well as angle, θR. It can be noted that the reference direction from which the angle θR(and angle θT) is measured may be measured from true north or based on any coordinate system used by the network for positioning (e.g., geographical coordinates, East-North-Up (ENU), etc.). As noted hereafter, solving for RRand θRcan be accomplished based on a known position of the UE105relative to base station120(to determine distance L). This position can be determined using any of the positioning techniques previously described with regard toFIGS.1-3, including GNSS-based decisioning and/or network-based positioning (e.g., positioning using multi-RTT, DL-TDOA, and/or AoD measurements etc.).

The distance RRcan be determined based on a time difference at the UE105of receiving the LOS reference signal460and echo signal470. Rsummay be defined as follows:
Rsum=RT+RR(1)
where RTis the distance between the base station120and target410, and RRis the distance between the target410and UE105. Using equation (1) and the geometry illustrated inFIG.4, RRmay then be determined as follows:

Rsumcan be determined using (i) the time difference between the LOS reference signal460and echo signal470, and (ii) the known distance between the base station120and UE105. This can be expressed mathematically as:
Rsum=(TRx_echo−TRxLOS−Δ)*c+L(3)
where L is the distance between the base station120and UE105, TRX_echois the time (e.g., ToA) at which the echo signal470is received at the UE105, TRx_LOSis the time (e.g., ToA) at which the LOS reference signal460is received at the UE105, and c is the speed of RF signals450,460, and470(e.g., the speed of light). Again, because the location of the UE105is known (or can be determined beforehand), distance L can be determined based on the UE location and the known location of the base station120(e.g., from an almanac of base station locations stored by the location server160and/or UE105).

The term Δ represents a time gap (if any) between the transmission of the LOS reference signal460and the transmission of the radar reference signal450. As discussed in more detail below, in some instances the LOS reference signal460and radar reference signal450may be the same RF signal, in which case the value for time gap Δ would be zero. In embodiments where the UE105determines the difference TRx_echo−TRxLOS, timing of LOS reference signal460and radar reference signal450may be provided to the UE105beforehand (e.g., in a communication session with the location server160or in a configuration provided to the UE105by the serving base station120). Because this difference is dependent solely on when signals arrive, rather than when they are transmitted, no synchronizations needed between the transmitter (base station120) and receiver (UE105). This can be advantageous in many circumstances.

Returning to equation (2), to solve for θRembodiments can use different techniques, depending on desired functionality and other factors. Because θRis an AoA at the UE105, the UE105may simply take an AoA measurement of the echo signal470. An AoA measurement can comprise determining which receive beam (e.g., as illustrated inFIG.3) has the highest RSRP value, and (optionally) performing super resolution/interpolation techniques to determine an accurate AoA. Additionally or alternatively, such as in instances where a UE105may not be capable of measuring AoA, multiple receivers (e.g., multiple UEs105) can be used (or a single UE105at multiple locations (if target410is static)) to determine θRusing multilateration. (Multilateration may be used in other ways to determine the location of target410, as discussed hereafter with regard toFIG.10.)

Having determined the values of L, Rsum, and θR, the value for RRcan be determined using equation (2), and the location of the target410(relative to the UE105) can be determined using RRand θR. Further, if the absolute position of the UE105is known, the absolute position of the target410can be determined.

According to some embodiments, a Doppler frequency for the target410can be determined in cases where the transmitter (base station120) and receiver (UE105) are both static. (Where UE105comprises a mobile device this may mean the UE105is temporarily immobile or has limited/low mobility (e.g., movement of several m/s or less)—at least for the duration of the radar measurements. Movement at the UE105can be determined using sensor information, GNSS or other positioning measurements, etc.) Target bistatic Doppler frequency fDcan be determined as:

fD=2⁢vc*cos⁢⁢δ*cos⁡(β/2),(4)
where velocity v and angles β and δ are related to the target410, radar reference signal450, and echo signal470as illustrated inFIG.4. Thus, techniques provided herein may enable RF sensing of a target410that can be used to determine location and velocity of the target.

As previously noted, embodiments may use a single reference signal or different reference signals for the radar reference signal450and LOS reference signal460.FIGS.5A and5Band the following description provide additional details.

FIGS.5A and5Bare diagrams of configurations of a base station120, target410, and UE105similar the configuration shown inFIG.4, provided to illustrate how beams may be used differently in different embodiments and/or situations, depending on desired functionality. InFIG.5A, for example, a single reference signal beam510is wide enough to be reflected from the target410and received by the UE105, allowing it to be used in the previously-described process regarding determining Rsum. As can be seen, whether the reference signal beam510is sufficiently wide may depend not only on the width of the reference signal beam, but also how close the target410and the UE105are to each other. (In some instances, for example, the target410and UE105may be sufficiently close such that a relatively narrow beam—as illustrated inFIG.5B, for example—may be both reflected from the target410and received by the UE105.) InFIG.5B, however, the target410is aligned with a first reference signal beam520, and a UE105is more aligned with a second reference signal beam530. In such instances, even if the UE105is capable of detecting both first reference signal beam520and a second reference signal beam530, it may be preferable for the UE105to take a ToA measurement of the second reference signal beam530, rather than the first reference signal beam520(e.g., due to more favorable SNR values to take a ToA measurement).

As noted, although reference signals using reference signal beams520,530may be transmitted at different times, because the time difference in the transmission of first reference signal beam520and the second reference signal beam530is known, this time difference can be accounted for by time gap Δ in equation (3), allowing for the determination of Rsumin cases where different reference signal beams transmitted at different times are used.FIGS.6and7are provided to help illustrate how embodiments may determine Rsumwhen a time gap Δ is or is not present.

FIG.6is a time-distance diagram illustrating how timing can be used to determine Rsumin the configuration shown inFIG.4, according to an embodiment. Here, a base station120transmits the LOS reference signal460and radar reference signal450at the same time. Thus, in this case, the LOS reference signal460and radar reference signal450may comprise the same signal (e.g., a DL-PRS), which may be transmitted using a single reference signal beam, as illustrated inFIG.5A. The different angles of reference signals450and460illustrated inFIG.5reflect the different paths of reference signals450and460inFIG.4.

As noted, the location server160may coordinate the transmission and measurement of the reference signals450and460by providing information to the base station120regarding how to transmit the reference signals450and460, as well as information to the UE105regarding when to measure the reference signals450and460. Further, depending on desired functionality, a single reference beam may be used for the determination of distance Rsumas described in relation toFIGS.4and5A.

FIG.7is a time-distance diagram, similar toFIG.6, providing another illustration of how timing can be used to determine Rsumin the configuration shown inFIG.4, according to an embodiment. In this case, the base station120transmits the LOS reference signal460and radar reference signal450different times: the radar reference signal450is transmitted after LOS reference signal460. As illustrated inFIG.5B, these reference signals may be transmitted using two beams. A time gap Δ represents the amount of time between the transmission of the radar reference signal450and the transmission of LOS reference signal460. Again, the location server160may coordinate the transmission and measurement of the reference signals450and460by providing information to the base station120regarding how to transmit the reference signals450and460, as well as information to the UE105regarding when to measure the reference signals450and460. Thus, the time gap Δ may be determined by the UE105based on the configuration received from the location server, which may be relayed to the UE105by the base station120.

The calculation of the position of the target410and/or values distance RTand angle θRmay be performed by different entities, depending on desired functionality. This may depend, for example, on whether a request for the position of the target410comes from the UE105or whether the request for the position of the target410comes from the network or other entity (such as the external client180ofFIG.1or external client230ofFIG.2). Accordingly, different processes can be used to determine the position of the target410.FIGS.8and9illustrate two example processes. It can be noted, however, that embodiments are not limited to the “positioning” of an object per se. RF sensing in the manner described herein may be conducted to obtain additional or alternative types of information regarding one or more objects/targets (e.g., object detection, identification, movement/object tracking, etc.)

FIG.8is a call-flow diagram illustrating an embodiment of a process of performing UE-based (or UE-initiated) RF sensing of a target410. As with the other figures provided herein,FIG.8is provided as a nonlimiting example. As discussed in more detail below, alternative embodiments may perform certain functions (e.g., the determination of the UE position, the AoD measurement, the ToA measurements, etc.) in a different order, simultaneously, etc. It can be noted that arrows between the various components illustrated inFIG.8illustrate messages or information sent from one component to another. It will be understood, however, that there may be any number of intervening devices, servers, etc. that may relay such messages, including other components inFIG.8. (E.g., a message from the UE105to the location server160may pass through the base station120, which may be the serving base station for the UE105.) Additionally, although wireless reference signals are referred to as PRS resources (e.g., DL-PRS transmitted by the base station120), alternative embodiments may utilize other wireless reference signal types. As noted, in some embodiments, a radar reference signal (e.g., radar reference signal450) may be a reference signal specialized to facilitate radar detection.

At block805, the target410receives a position request. This position request may come, for example, from an application (or app) executed by the target410. This may be a result from user interaction with the target410, based on a determined schedule, or based on other triggers (including user input). Additionally or alternatively, a position request may come from a separate device. In some instances, for example, the target410itself may be capable of communicating with the UE105and requesting its position.

In response, the target410may generate a position request notification. As indicated at arrow810, the request can be sent to the location server160, which can coordinate the transmission of the PRS resources (or other reference signals) by the base station120to determine of the position of the target410. According to some embodiments, additional communications between the target410and location server160may occur to determine capabilities of the target410(including, for example, the capability of the UE105to detect the location of the target410). In some embodiments, communication between the location server160and target410may occur via an LPP positioning session.

At block815, the UE105determines its position. This can be performed in any of a variety of ways, including GNSS and/or other non-network means. Additionally or alternatively, position determination for the UE105can be network-based and may involve the location server160. In such instances, the UE105and a location server160may engage in a positioning session as shown by arrow820. Depending on desired functionality, this may be a positioning session separate from an earlier positioning session initiated to determine the location of the target410or may be incorporated into the earlier positioning session. In some embodiments, the UE105may obtain a high-accuracy position determination based on, for example, multi-RTT positioning based on communication with a plurality of base stations (which may include communication with the base station120). For multi-RTT positioning, assistance data may be obtained from the location server160(e.g., in positioning session at arrow820) may include a location of each base station with which RTT measurements are made.

As indicated by arrow835, the location server can then schedule the transmission and receipt of PRS resources by the base station120and UE105. More specifically, the scheduling of PRS resources may involve the location server160configuring the base station120to transmit the one or more PRS resources, and/or the location server160or base station120configuring the UE105to measure the one or more PRS resources.

At block845, the base station120transmits the one or more PRS resources. As described in the earlier embodiments, the one or more PRS resources may comprise a single RF signal transmitted using a wide beam (e.g., as shown inFIG.5A) or separate RF signals transmitted using separate names (e.g., as shown inFIG.5B). In either case, the UE105can measure the ToA of both the LOS reference signal460and echo signal470. The measurement of these ToAs is shown at block850. As mentioned, the UE105may also take an AoA measurement of the echo signal470to determine the angle θRof the target.

At block855, the UE105determines the distance and angle of the target. This can be done using the processes described above for determining distance (RR) and angle (θR). Again, the angle of the target410may be determined using an AoA measurement or using multilateration. In the case of multilateration, additional measurements (e.g. ToA measurements of the echo signal from the PRS resource transmitted at arrow845, or from another PRS resource) may be obtained from other UEs, or (if the target410is static) may be obtained by the UE105itself, at different times and in different locations.

At block860, the UE105determines the position of the target410. This can be done by using equations (1)-(3) in the manner previously described. More specifically, using the angle and distance of the target410as determined at block855, and a known location for the UE105, the UE105can determine the position of the target410. This determined position can then be provided by the UE105, as indicated at block865.

The way in which the position of the target410is provided at block865may be dependent on the way in which the position was requested at block805. If, for example, the position of the target410was requested by an application executed at the UE105, providing the position may therefore comprise providing the position to an application layer (e.g., from a lower layer that determined the position of the target). If requested by a user of the UE105, the UE105can provide the position visibly and/or audibly (e.g., using a display and/or speakers of the UE105). If the position of the target410was requested by the target410itself, the UE105can communicate the position back to the target410.

FIG.9is call-flow diagram illustrating an embodiment of a process of performing UE-assisted (or network-initiated) RF sensing of a target410. Here, calculations and position determination are performed at the location server160, based on information received from the UE105and target410. Many of the operations performed in the process ofFIG.9may be similar to the operations performed in the process ofFIG.8, as previously described.

This process may begin with a position request obtained at the location server160, as indicated at block905. As indicated previously, UE-assisted (or network-based) positioning can be based on a request from an external client (e.g., external client180ofFIG.1and/or external client230ofFIG.2). Additionally or alternatively, the request may come from a service within the wireless network that may need the position of the target410to provide particular functionality.

In response to the position request, the location server160may notify the UE105of the position request via position request notification, as indicated at arrow910. In some embodiments, this may comprise initiating a communication session between the location server160and UE105.

The determination of the UE position at block915is made by the location server, in which case a positioning session920may be conducted to determine the location of the UE105using network-based positioning. Alternatively, if the UE105knows or can obtain its position separate from the network (e.g., using GNSS positioning), the UE105may provide its position to the location server160. Elements935-950may be similar to corresponding features inFIG.8, as previously described.

Once the UE105measures the ToAs at block950, it can send positioning information to the location server160, as indicated at action953. This positioning information may comprise the measurements themselves and/or information indicative of a time difference between the ToAs.

Elements955-965may be similar to corresponding elements inFIG.8. The difference inFIG.9, however, is that these operations are performed at the location server160. That is, using the positioning information sent by the UE105at action953, the location server can determine the distance and angle of the target410and, ultimately, determine the position of the target410, using the techniques described above or similar thereto. Providing the position of the target410at block965may comprise communicating the position to a requesting entity (e.g., the entity providing the position request at block905).

FIG.10is a simplified diagram illustrating a variation to the configuration illustrated inFIG.4, which may be performed according to embodiments. Here, rather than a single UE105, multiple UEs105-1,105-2, and105-3(collectively and generically referred to herein simply as UEs105) are used. To reduce clutter, the location server160has been removed fromFIG.10, although, as indicated below, a location server160may be used in a manner similar to the manner described with respect toFIG.4.

The process of determining the location of the target410may be generally similar to the process illustrated inFIG.4and described in conjunction withFIGS.4-9. However, because multiple UEs105are used, angle information may not be needed. That is, rather than (or in addition to) determining the position of the target410using distance RRand angle θR, the position may be determined instead using multi-lateration. To do so, each UE105may receive a respective echo signal470from the target410, as well as a direct reference signal from the base station120(similar to LOS reference signal460inFIG.4) to determine a respective determine Rsumusing equation (3). (To reduce clutter, direct reference signals are not illustrated inFIG.10.) Because Rsumis the sum of RTand the respective RRfor each UE105, the value of Rsumcan be used to form a respective ellipse480for each UE105, in which the base station120and UE105are foci of the respective ellipse. (Again, to reduce clutter, only applicable portions of ellipses480are illustrated inFIG.10) The device determining the location of the target410(e.g., any/all of the UEs105and/or the location server160(not illustrated inFIG.10)) may do so by determining the point at which the ellipses480converge. As such, no AoA or other angular determinations may be needed to determine the location of the target410.

The number of UEs105used to determine the position of the target410in this manner may vary, depending on the situation. A larger or smaller number of UEs105than illustrated inFIG.10, for example, can be used. In some circumstances, such as when two UEs105are used, there may be ambiguities (e.g., multiple convergence points) in the position of the target410. In such instances, other data can be leveraged to resolve the ambiguities. This other data can include, for example, tracking information for the target410, other (previous and/or simultaneous) position determinations for the target410, or the like.

It can be noted that embodiments for determining the location of the target410in the manner illustrated inFIG.10may follow a similar process as those illustrated inFIGS.8-9. Because multiple UEs105are used, the functionality of the UE105illustrated inFIGS.8-9may be replicated for all UEs105. That said, the determination of the position of the target at block860ofFIG.8may be performed by a single UE105, if desired. To do so, the UE105may perform multilateration calculations based on positioning information (e.g., ToA measurements and/or time-difference determinations) received from the other UEs. This information may be received directly from the other UEs (e.g., using sidelink communications) or indirectly via the location server160and/or base station120.

FIG.11is a flow diagram of a method1100of performing RF sensing with a mobile device in a wireless communication network, according to an embodiment. Here, the mobile device may correspond with the UE105, as described inFIGS.4-10. Further, the position of the object is determined by the mobile device. And thus, the method1100may be similar to the functionality of the UE105as illustrated inFIG.8and described above. Means for performing the functionality illustrated in one or more of the blocks shown inFIG.11may be performed by hardware and/or software components of a UE105. Example components of a UE105are illustrated inFIG.14and described in more detail below.

At block1110, the functionality comprises receiving, at the mobile device, a configuration from a server, wherein the configuration includes timing information for each of one or more wireless reference signals transmitted by a network entity of the wireless communications network. As noted in the previously-described embodiments, a UE105may be configured to measure one or more reference signals. This configuration may be received by the location server. Further, as indicated in the above-described embodiments, the network entity may comprise a base station. More broadly, the network entity may comprise any type of base station or TRP (including a gNB or eNB, for example). In some embodiments, a network entity may alternatively comprise another UE having a known location and capable of performing the operations of a base station as indicated in the previously-described embodiments. Where the network entity comprises a base station or TRP, the wireless reference signals may comprise a downlink (DL) reference signal such as a PRS, SSB, Tracking Reference Signal (TRS), Channel State Information Reference Signal (CSIRS), Demodulation Reference Signal (DMRS), etc. Where the network entity comprises another UE, the wireless reference signal may comprise a sidelink (SL) reference signal, such as an SL-PRS, DMRS, CSIRS, etc.

As indicated in the embodiments above, the configuration itself may include various types of information regarding the one or more wireless reference signals. Thus, according to some embodiments of the method1100, for each of the one or more wireless reference signals, the configuration may comprise a signal type of the respective wireless reference signal, a duration of the respective wireless reference signal, a center frequency and bandwidth of the respective wireless reference signal, or a period and prepetition factor of the respective wireless reference signal, or any combination thereof. Additionally or alternatively, for each of the one or more wireless reference signals, the timing information may comprise a time at which the respective reference signal is transmitted by the network entity, or a time at which the respective reference signal is expected to be received at the mobile device, or any combination thereof.

According to some embodiments, the operations illustrated inFIG.11may be performed in response to a request at the mobile device for the position of an object or target. As indicated with arrow810ofFIG.8, the mobile device can then respond by sending a position request to the location server160. Accordingly, some embodiments of the method1100may comprise, prior to receiving the configuration from the server, sending a request to the server to perform the RF sensing.

Means for performing functionality at block1110may comprise a bus1405, wireless communication interface1430, digital signal processor (DSP)1420, processing unit(s)1410, memory1460, and/or other components of a mobile device, as illustrated inFIG.14.

At block1120, the functionality comprises determining, with the mobile device and based on the configuration, (i) a first ToA of an LOS wireless signal at the mobile device, wherein the LOS wireless signal comprises a first wireless reference signal of the one or more wireless reference signals, and (ii) a second ToA of an echo signal at the mobile device, wherein the echo signal comprises a reflection, from an object, of the first wireless reference signal or a second wireless reference signal of the one or more wireless reference signals. An example time difference is provided in equation (3) as TRx_echo−TRxLOS. As noted, Doppler for the object, too, may be measured. Thus, according to some embodiments of the method1100, the echo signal comprises a reflection of the first wireless reference signal from the object, and the mobile device further estimates Doppler from the echo signal.

As described in the embodiments above, if ToA measurements are of different wireless signals (e.g., the first wireless reference signal and the second wireless reference signal) transmitted at different times, a time delay (e.g., time gap Δ) can be accounted for. Thus, according to some embodiments of the method1100, the echo signal comprises a reflection of the second wireless reference signal from the object, and determining the position of the object may be further based on a difference between a time the network entity transmits the first wireless reference signal and a time the network entity transmits the second reference signal. In some embodiments, determining the difference between the time the network entity transmits the first wireless reference signal and the time the network entity transmits the second reference signal based on the timing information in the configuration.

Means for performing functionality at block1120may comprise a bus1405, wireless communication interface1430, digital signal processor (DSP)1420, processing unit1410, memory1460, and/or other components of a mobile device, as illustrated inFIG.14.

At block1130, the functionality comprises determining, with the mobile device, a position of the mobile device relative to the network entity. As illustrated in the embodiments above, a distance L between the mobile device and network entity can be used to determine Rsumand ultimately RR. According to some embodiments, this distance may be determined by a location server or mobile device and may be derived from determined positions of the network entity and mobile device. For immobile network entities (e.g., base stations), an almanac or index of such network entities may be accessed and/or maintained by the location server, and further may be provided to the mobile device. Such embodiments may comprise receiving a location of the network entity from the server, wherein determining the position of the mobile device relative to the network entity is based, at least in part, on the location of the network entity. In some embodiments, the first wireless reference signal may be used not only to determine the position of the object, but also the position of the mobile device. For example, in some embodiments the first wireless reference signal may comprise a PRS. In such embodiments, this PRS may further be used in network-based positioning of the mobile device. A such, in some embodiments of the method1100, determining the position of the mobile device relative to the network entity is based, at least in part, on the PRS.

Means for performing functionality at block1130may comprise a bus1405, wireless communication interface1430, digital signal processor (DSP)1420, processing unit1410, memory1460, and/or other components of a mobile device, as illustrated inFIG.14.

At block1140, the functionality comprises determining with the mobile device, a position of the object based on (i) a time difference between the first ToA and the second ToA, and (ii) the position of the mobile device relative to the network entity. Again, the time difference and position of the mobile device relative to the network entity can be used to solve for equations (2) and (3). As noted, according to some embodiments, and AoA measurement at the mobile device may be used to determine angle θRof equation (2). Alternatively, as indicated inFIG.10, the mobile device may be one of multiple mobile devices making ToA measurements of the one or more wireless reference signals. In such instances, Rsumcan be determined (e.g., using equation (3)) for each mobile device, and the position of the object can be determined using multilateration (e.g., by identifying a point at which ellipses derived from each Rsumconverge with one another.)

Means for performing functionality at block1140may comprise a bus1405, wireless communication interface1430, digital signal processor (DSP)1420, processing unit1410, memory1460, and/or other components of a mobile device, as illustrated inFIG.14.

At block1150, the functionality comprises providing the position of the object with the mobile device. As previously noted, the way in which the position is provided can vary depending on circumstance. According to some embodiments, the determination of the position of the object may be carried out using a specialized application or lower-level function, in which case providing the position of the object may comprise providing the position of the object to an application executed by the mobile device.

Means for performing functionality at block1150may comprise a bus1405, wireless communication interface1430, digital signal processor (DSP)1420, processing unit1410, memory1460, and/or other components of a mobile device, as illustrated inFIG.14.

FIG.12is a flow diagram of another method1200of performing RF sensing with a mobile device in a wireless communication network, according to an embodiment. Again, the mobile device may correspond with the UE105, as described inFIGS.4-10. Here, however, the method1200may be similar to the functionality of the UE105as illustrated inFIG.9and described above, in which the position of the object may be determined by a server. Means for performing the functionality illustrated in one or more of the blocks shown inFIG.12may be performed by hardware and/or software components of a UE105. Example components of a UE105are illustrated inFIG.14and described in more detail below.

At block1210, the functionality comprises receiving, by the mobile device, a request from a server to conduct RF sensing. As discussed above in relation toFIG.9, a location server may receive a position request (e.g., from within the wireless communication network or from an external entity) for an object/target and, in turn, send a position request notification to the mobile device to conduct RF sensing as described herein. Other triggers and sources for the position request may exist. Embodiments are not limited to the positioning of an object, for example, and requests for RF sensing in the manner described herein may be requests for other types of information (e.g., object detection, identification, movement/object tracking, etc.). The positioning request notification, according to some embodiments, may be part of a larger positioning or communication session between the server and mobile device. Means for performing functionality at block1210may comprise a bus1405, wireless communication interface1430, digital signal processor (DSP)1420, processing unit1410, memory1460, and/or other components of a mobile device, as illustrated inFIG.14.

At block1220, the functionality comprises, subsequent to receiving the request, receiving, at the mobile device, a configuration from a server, wherein the configuration includes timing information for each of one or more wireless reference signals transmitted by a network entity of the wireless communications network. Similar to the functionality of block1110inFIG.11, the configuration at block1220may enable the mobile device to measure one or more reference signals transmitted by a network entity. Again, according to some embodiments, for each of the one or more wireless reference signals, the configuration may comprise a signal type of the respective wireless reference signal, a duration of the respective wireless reference signal, a center frequency and bandwidth of the respective wireless reference signal, or a period and prepetition factor of the respective wireless reference signal, or any combination thereof. Additionally or alternatively, for each of the one or more wireless reference signals, the timing information may comprise a time at which the respective reference signal is transmitted by the network entity, or a time at which the respective reference signal is expected to be received at the mobile device, or any combination thereof. Means for performing functionality at block1220may comprise a bus1405, wireless communication interface1430, digital signal processor (DSP)1420, processing unit1410, memory1460, and/or other components of a mobile device, as illustrated inFIG.14.

At block1230, the functionality comprises determining, with the mobile device and based on the configuration, (i) a first Time of Arrival (ToA) of a Line-Of-Sight (LOS) wireless signal at the mobile device, wherein the LOS wireless signal comprises a first wireless reference signal of the one or more wireless reference signals, and (ii) a second ToA of an echo signal at the mobile device, wherein the echo signal comprises a reflection, from an object, of the first wireless reference signal or a second wireless reference signal of the one or more wireless reference signals. As noted, a determined time difference between these ToAs can be used can be used to determine Rsumand ultimately the location of the object. According to some embodiments, the first wireless reference signal comprises a PRS (e.g., DL-PRS transmitted by a base station). Means for performing functionality at block1230may comprise a bus1405, wireless communication interface1430, digital signal processor (DSP)1420, processing unit1410, memory1460, and/or other components of a mobile device, as illustrated inFIG.14.

At block1240, the functionality comprises sending, from the mobile device to the server, information indicative of a time difference between the first ToA and the second ToA. According to some embodiments, the information provided by the mobile device at block1240may vary. For example, according to some embodiments, the method1200may further comprise determining a position of the mobile device and sending information indicative of the position of the mobile device to the server. Additionally or alternatively, in embodiments in which the echo signal comprises a reflection of the first wireless reference signal from the object, and the method1200may further comprise estimating, with the mobile device, Doppler from the echo signal and sending the estimated Doppler from the mobile device to the server.

Means for performing functionality at block1240may comprise a bus1405, wireless communication interface1430, digital signal processor (DSP)1420, processing unit1410, memory1460, and/or other components of a mobile device, as illustrated inFIG.14.

FIG.13is a flow diagram of method1300of performing RF sensing in a wireless communication network, according to an embodiment. Again, the mobile device may correspond with the UE105, as described inFIGS.4-10. The method1300may be similar to the functionality of the location server160as illustrated inFIG.9and described above, in which the position of the object may be determined by the location server. Means for performing the functionality illustrated in one or more of the blocks shown inFIG.13may be performed by hardware and/or software components of a computer system. Example components of a computer system are illustrated inFIG.15and described in more detail below.

At block1310, the functionality comprises sending a configuration from the server to the mobile device, wherein the configuration includes timing information for each of one or more wireless reference signals transmitted by a network entity of the wireless communications network. Similar to the configuration described in the methods shown inFIGS.11-12, the configuration at block1310may enable the mobile device to measure one or more reference signals transmitted by a network entity. Again, according to some embodiments, for each of the one or more wireless reference signals, the configuration may comprise a signal type of the respective wireless reference signal, a duration of the respective wireless reference signal, a center frequency and bandwidth of the respective wireless reference signal, or a period and prepetition factor of the respective wireless reference signal, or any combination thereof. Additionally or alternatively, for each of the one or more wireless reference signals, the timing information may comprise a time at which the respective reference signal is transmitted by the network entity, or a time at which the respective reference signal is expected to be received at the mobile device, or any combination thereof.

Means for performing functionality at block1310may comprise a bus1505, communication interface1530, processing unit(s)1510, working memory1535, and/or other components of a computer system, as illustrated inFIG.15.

At block1320, the functionality comprises, subsequent to sending the configuration, receiving, with the server, information indicative of a time difference between a first ToA and a second ToA, wherein the first ToA comprises a ToA of a Line-Of-Sight (LOS) wireless signal at the mobile device, wherein the LOS wireless signal comprises a first wireless reference signal of the one or more wireless reference signals, and the second ToA comprises a ToA of an echo signal at the mobile device, wherein the echo signal comprises a reflection, from the object, of the first wireless reference signal or a second wireless reference signal of the one or more wireless reference signals. Again, this time difference between ToAs can be used can be used to determine Rsumand ultimately the location of the object. According to some embodiments, the first wireless reference signal comprises a PRS (e.g., DL-PRS transmitted by a base station). As noted, Doppler may also be sent from the mobile device to the server. In such embodiments, the echo signal may comprise a reflection of the first wireless reference signal from the object and the method1300may further comprise receiving, at the server, an estimated Doppler from the mobile device.

Means for performing functionality at block1320may comprise a bus1505, communication interface1530, processing unit(s)1510, working memory1535, and/or other components of a computer system, as illustrated inFIG.15.

At block1330, the functionality comprises determining, with the server, a position of the mobile device relative to the network entity. As described in the embodiments above, the determination can be made based on a determination of the location of the mobile device itself (e.g., using network-based positioning of the mobile device, a GNSS position provided by the mobile device, etc.) and a location of the network entity. Again, an almanac or directory of the locations of network entities such as base stations and other TRPs may be accessible and/or maintained by the server. Means for performing functionality at block1330may comprise a bus1505, processing unit(s)1510, working memory1535, and/or other components of a computer system, as illustrated inFIG.15.

At block1340, the functionality comprises determining, with the server, the position of the object based on (i) a time difference between the first ToA and the second ToA, and (ii) the position of the mobile device relative to the network entity. Again, the time difference and position of the mobile device relative to the network entity can be used to solve for equations (2) and (3). As noted, according to some embodiments, and AoA measurement at the mobile device may be used to determine angle θRof equation (2). Alternatively, as indicated inFIG.10, the mobile device may be one of multiple mobile devices making ToA measurements of the one or more wireless reference signals. In such instances, Rsumcan be determined (e.g., using equation (3)) for each mobile device, and the position of the object can be determined using multilateration (e.g., by identifying a point at which ellipses derived from each Rsumconverge with one another.) In such embodiments, the server may therefore perform the operations of blocks1310-1330or multiple mobile devices, making the determination of the position of the object at block1340based on information received from the mobile devices.

Means for performing functionality at block1340may comprise a bus1505, communication interface1530, processing unit(s)1510, working memory1535, and/or other components of a computer system, as illustrated inFIG.15.

The functionality at block1350comprises sending, to the requesting entity, the position of the object to a device. As noted, the device may comprise a requesting entity internal or external to the mobile communication network. In such embodiments, the method1300may further comprise receiving, at a server, a request from a requesting entity for the position of an object, and responsive to receiving the request for the position of the object, sending a request from the server to the mobile device to conduct RF sensing. In such embodiments, sending the configuration may be subsequent to sending the request to the mobile device, and sending the position of the object to the device may comprise sending the position of the object to the requesting entity.

Means for performing functionality at block1350may comprise a bus1505, communication interface1530, processing unit(s)1510, working memory1535, and/or other components of a computer system, as illustrated inFIG.15.

FIG.14illustrates an embodiment of a mobile device1400, which can be utilized as a target, UE, or other UE as described herein above (e.g., in association withFIGS.1-13). For example, the mobile device1400can perform one or more of the functions of the methods shown inFIGS.11-12. It should be noted thatFIG.14is meant only to provide a generalized illustration of various components, any or all of which may be utilized as appropriate. It can be noted that, in some instances, components illustrated byFIG.14can be localized to a single physical device and/or distributed among various networked devices, which may be disposed at different physical locations. Furthermore, as previously noted, the functionality of the UE discussed in the previously described embodiments may be executed by one or more of the hardware and/or software components illustrated inFIG.14.

The mobile device1400is shown comprising hardware elements that can be electrically coupled via a bus1405(or may otherwise be in communication, as appropriate). The hardware elements may include a processing unit(s)1410which can include without limitation one or more general-purpose processors, one or more special-purpose processors (such as DSP chips, graphics acceleration processors, application specific integrated circuits (ASICs), and/or the like), and/or other processing structures or means. As shown inFIG.14, some embodiments may have a separate DSP1420, depending on desired functionality. Location determination and/or other determinations based on wireless communication may be provided in the processing unit(s)1410and/or wireless communication interface1430(discussed below). The mobile device1400also can include one or more input devices1470, which can include without limitation one or more keyboards, touch screens, touch pads, microphones, buttons, dials, switches, and/or the like; and one or more output devices1415, which can include without limitation one or more displays (e.g., touch screens), light emitting diodes (LEDs), speakers, and/or the like.

The mobile device1400may also include a wireless communication interface1430, which may comprise without limitation 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.), and/or the like, which may enable the mobile device1400to communicate with other devices as described in the embodiments above. The wireless communication interface1430may permit data and signaling to be communicated (e.g., transmitted and received) with TRPs of a network, (e.g., including eNBs, gNBs, ng-eNBs), access points, various base stations and/or other access node types, and/or other network components, computer systems, and/or any other electronic devices (UEs/mobile devices, etc.) communicatively coupled with TRPs, as described herein. The communication can be carried out via one or more wireless communication antenna(s)1432that send and/or receive wireless signals1434. According to some embodiments, the wireless communication antenna(s)1432may comprise a plurality of discrete antennas, antenna arrays, or any combination thereof.

Depending on desired functionality, the wireless communication interface1430may comprise a separate receiver and transmitter, or any combination of transceivers, transmitters, and/or receivers to communicate with TRPs (e.g., ng-eNBs and gNBs) and other terrestrial transceivers, such as wireless devices and access points. The mobile device1400may communicate with different data networks that 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, and so on. A CDMA network may implement one or more RATs such as CDMA2000, WCDMA, and so on. CDMA2000 includes IS-95, IS-2000 and/or IS-856 standards. A TDMA network may implement GSM, Digital Advanced Mobile Phone System (D-AMPS), or some other RAT. An OFDMA network may employ LTE, LTE Advanced, 5G NR, and so on. 5G NR, LTE, LTE Advanced, GSM, and WCDMA are described in documents from 3GPP. Cdma2000 is described in documents from a consortium named “3rd Generation Partnership Project X3” (3GPP2). 3GPP and 3GPP2 documents are publicly available. A wireless local area network (WLAN) may also be an IEEE 802.11x network, and a 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.

The mobile device1400can further include sensor(s)1440. Sensors1440may comprise, without limitation, one or more inertial sensors and/or other sensors (e.g., accelerometer(s), gyroscope(s), camera(s), magnetometer(s), altimeter(s), microphone(s), proximity sensor(s), light sensor(s), barometer(s), and the like), some of which may be used to obtain position-related measurements and/or other information.

Embodiments of the mobile device1400may also include a Global Navigation Satellite System (GNSS) receiver1480capable of receiving signals1484from one or more GNSS satellites using an antenna1482(which could be the same as antenna1432). Positioning based on GNSS signal measurement can be utilized to complement and/or incorporate the techniques described herein. The GNSS receiver1480can extract a position of the mobile device1400, using conventional techniques, from GNSS satellites140of a GNSS system, such as Global Positioning System (GPS), Galileo, GLONASS, Quasi-Zenith Satellite System (QZSS) over Japan, Indian Regional Navigational Satellite System (IRNSS) over India, BeiDou Navigation Satellite System (BDS) over China, and/or the like. Moreover, the GNSS receiver1480can be used with various augmentation systems (e.g., a Satellite Based Augmentation System (SBAS)) that may be associated with or otherwise enabled for use with one or more global and/or regional navigation satellite systems, such as, e.g., Wide Area Augmentation System (WAAS), European Geostationary Navigation Overlay Service (EGNOS), Multi-functional Satellite Augmentation System (MSAS), and Geo Augmented Navigation system (GAGAN), and/or the like.

It can be noted that, although GNSS receiver1480is illustrated inFIG.14as a distinct component, embodiments are not so limited. As used herein, the term “GNSS receiver” may comprise hardware and/or software components configured to obtain GNSS measurements (measurements from GNSS satellites). In some embodiments, therefore, the GNSS receiver may comprise a measurement engine executed (as software) by one or more processing units, such as processing unit(s)1410, DSP1420, and/or a processing unit within the wireless communication interface1430(e.g., in a modem). A GNSS receiver may optionally also include a positioning engine, which can use GNSS measurements from the measurement engine to determine a position of the GNSS receiver using an Extended Kalman Filter (EKF), Weighted Least Squares (WLS), a hatch filter, particle filter, or the like. The positioning engine may also be executed by one or more processing units, such as processing unit(s)1410or DSP1420.

The memory1460of the mobile device1400also can comprise software elements (not shown inFIG.14), including an operating system, device drivers, executable libraries, and/or other code, such as one or more application programs, which may comprise computer programs provided by various embodiments, and/or may be designed to implement methods, and/or configure systems, provided by other embodiments, as described herein. Merely by way of example, one or more procedures described with respect to the method(s) discussed above may be implemented as code and/or instructions in memory1460that are executable by the mobile device1400(and/or processing unit(s)1410or DSP1420within mobile device1400). In an aspect, then such code and/or instructions can 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.

FIG.15is a block diagram of an embodiment of a computer system1500, which may be used, in whole or in part, to provide the functions of one or more network components as described in the embodiments herein (e.g., location server160ofFIGS.1,4,8, and9). It should be noted thatFIG.15is meant only to provide a generalized illustration of various components, any or all of which may be utilized as appropriate.FIG.15, therefore, broadly illustrates how individual system elements may be implemented in a relatively separated or relatively more integrated manner. In addition, it can be noted that components illustrated byFIG.15can be localized to a single device and/or distributed among various networked devices, which may be disposed at different geographical locations.

The computer system1500is shown comprising hardware elements that can be electrically coupled via a bus1505(or may otherwise be in communication, as appropriate). The hardware elements may include processing unit(s)1510, which may comprise without limitation one or more general-purpose processors, one or more special-purpose processors (such as digital signal processing chips, graphics acceleration processors, and/or the like), and/or other processing structure, which can be configured to perform one or more of the methods described herein. The computer system1500also may comprise one or more input devices1515, which may comprise without limitation a mouse, a keyboard, a camera, a microphone, and/or the like; and one or more output devices1520, which may comprise without limitation a display device, a printer, and/or the like.

The computer system1500may further include (and/or be in communication with) one or more non-transitory storage devices1525, which can comprise, without limitation, local and/or network accessible storage, and/or may comprise, without limitation, a disk drive, a drive array, an optical storage device, a solid-state storage device, such as a RAM and/or ROM, which can be programmable, flash-updateable, and/or the like. Such storage devices may be configured to implement any appropriate data stores, including without limitation, various file systems, database structures, and/or the like. Such data stores may include database(s) and/or other data structures used store and administer messages and/or other information to be sent to one or more devices via hubs, as described herein.

The computer system1500may also include a communications subsystem1530, which may comprise wireless communication technologies managed and controlled by a wireless communication interface1533, as well as wired technologies (such as Ethernet, coaxial communications, universal serial bus (USB), and the like). The wireless communication interface1533may send and receive wireless signals1555(e.g., signals according to 5G NR or LTE) via wireless antenna(s)1550. Thus the communications subsystem1530may comprise a modem, a network card (wireless or wired), an infrared communication device, a wireless communication device, and/or a chipset, and/or the like, which may enable the computer system1500to communicate on any or all of the communication networks described herein to any device on the respective network, including a UE/mobile device, base stations and/or other TRPs, and/or any other electronic devices described herein. Hence, the communications subsystem1530may be used to receive and send data as described in the embodiments herein.

In many embodiments, the computer system1500will further comprise a working memory1535, which may comprise a RAM or ROM device, as described above. Software elements, shown as being located within the working memory1535, may comprise an operating system1540, device drivers, executable libraries, and/or other code, such as one or more applications1545, which may comprise computer programs provided by various embodiments, and/or may be designed to implement methods, and/or configure systems, provided by other embodiments, as described herein. Merely by way of example, one or more procedures described with respect to the method(s) discussed above might be implemented as code and/or instructions executable by a computer (and/or a processing unit within a computer); in an aspect, then, such code and/or instructions can 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.