Patent ID: 12200657

Elements are indicated by numeric labels in the figures with like numbered elements in different figures representing the same element or similar elements. Different instances of a common element are indicated by following a numeric label for the common element with a distinct numeric suffix. In this case, a reference to the numeric label without a suffix indicates any instance of the common element. For example,FIG.1contains four distinct network cells, labelled110a,110b,110c, and110d. A reference to a cell110then corresponds to any of the cells110a,110b,110c, and110d.

DETAILED DESCRIPTION

The terms “mobile device”, “mobile stations” (MS), “user equipment” (UE) and “target” are used interchangeably herein and may refer to a device such as a cellular or other wireless communication device, personal communication system (PCS) device, personal navigation device (PND), Personal Information Manager (PIM), Personal Digital Assistant (PDA), laptop, smartphone, tablet or other suitable mobile device which is capable of receiving wireless communication and/or navigation signals. The terms are also intended to include devices which communicate with a personal navigation device (PND), such as by short-range wireless, infrared, wireline connection, or other connection—regardless of whether satellite signal reception, assistance data reception, and/or position-related processing occurs at the device or at the PND.

In addition, the terms MS, UE, “mobile device” or “target” are intended to include all devices, including wireless and wireline communication devices, computers, laptops, etc., which are capable of communication with a server, such as via the Internet, WiFi, cellular wireless network, Digital Subscriber Line (DSL) network, packet cable network or other network, and regardless of whether satellite signal reception, assistance data reception, and/or position-related processing occurs at the device, at a server, or at another device associated with the network. Any operable combination of the above are also considered a “mobile device.”

The detailed description set forth below, in connection with the appended drawings, is intended as a description of various configurations and is not intended to represent the only configurations in which the concepts described herein may be practiced. The detailed description includes specific details for the purpose of providing a thorough understanding of the various concepts. However, it will be apparent to those skilled in the art that these concepts may be practiced without these specific details. In some instances, well-known structures and components are shown in block diagram form in order to avoid obscuring such concepts.

The techniques described herein may be used for various wireless communication networks such as code-division multiple access (CDMA), time-division multiple access (TDMA), frequency-division multiple access (FDMA), orthogonal frequency-division multiple access (OFDMA), single-carrier FDMA (SC-FDMA) and other networks. The terms “network” and “system” are often used interchangeably. A CDMA network may implement a radio technology such as Universal Terrestrial Radio Access (UTRA), cdma2000, etc. UTRA includes Wideband CDMA (WCDMA) and other variants of CDMA. cdma2000 covers IS-2000, IS-95 and IS-856 standards. A TDMA network may implement a radio technology such as Global System for Mobile Communications (GSM). An OFDMA network may implement a radio technology such as Evolved UTRA (E-UTRA), Ultra Mobile Broadband (UMB), IEEE 802.11 (Wi-Fi), IEEE 802.16 (WiMAX), IEEE 802.20, Flash-OFDMA, etc. UTRA and E-UTRA are part of Universal Mobile Telecommunication System (UMTS). 3GPP Long Term Evolution (LTE) and LTE-Advanced (LTE-A) are new releases of UMTS that use E-UTRA. UTRA, E-UTRA, UMTS, LTE, LTE-A and GSM are described in documents from an organization named “3rd Generation Partnership Project” (3GPP). CDMA2000 and UMB are described in documents from an organization named “3rd Generation Partnership Project 2” (3GPP2). The techniques described herein may be used for the wireless networks and radio technologies mentioned above as well as other wireless networks and radio technologies, such as a next generation (e.g., 5th Generation (5G) new radio (NR) operating in mmWave bands) network.

Beamformed transmissions are expected to be widespread deployed in 5G NR deployments using spectrum under 6 GHz, e.g., sub-6, and mmWave, which operates using a spectrum above 24 GHz. For example, a base station with a large number of antenna elements may beamform to transmit beams in a sets of beams over a range of horizontal (azimuthal) angles and vertical (elevation) angles to form a spatial grid of beams.

A UE may adopt a signaling/report according to a “Time of First Detected”/“Time of Arrival” metric, instead of L1-Reference Signal Received Power (RSRP) metric. Thus, a beam of interest to a UE are the beams from a base station with the first detected channel tap that is the earliest and beams whose first detected channel tap is within a predetermined delay from the first detected tap of the beam with earliest first tap.

In 5G NR a base stations may transmit a downlink (DL) positioning reference signal (PRS) that is processed and measured by a UE for determining a location estimate of the UE. For example, a UE may generate positioning measurements from the DL PRS such as Reference Signal Time Difference (RSTD), Reference Signal Received Power (RSRP), and reception and transmission (RX-TX) time difference measurements, which may be used to determine a location estimate for the UE using various positioning methods, such as Time Difference of Arrival (TDOA), Angle of Departure (AoD), and multi-cell Round Trip Time (RTT). In some implementations, the UE may generate positioning measurements using DL PRS which may be sent to a remote location server to calculate a location estimate for the UE in UE assisted positioning process or the UE may calculate its own location estimate in a UE based positioning process.

In 5G NR, PRS signals have been provided with expanded flexibility with respect to LTE. For example, in 5G NR, PRS may be transmitted with multiple symbol and Comb options per subframe and may be transmitted on multiple subframes, i.e., repeated in the time domain for each positioning occasion. Moreover, multiple beams may transmit each PRS and the beams may be repeated to improve performance. Further, multiple PRS occasions may be used.

The expanded PRS flexibility, however, results in significantly increased power and processing requirements for receiving PRS. Improvements are needed to reduce memory and processing requirement for PRS reception using 5G NR.

Accordingly, in one implementation, positioning of a mobile device may be supported by dividing the PRS processing into two separate modes, e.g., an acquisition mode and a tracking mode. In the acquisition mode, the mobile device performs a fast scan of all of the beams from a base station transmitting PRS using less than the full set of resources for the PRS. For example, the mobile device may acquire the PRS in each beam using less than the full bandwidth of the PRS, less than the full number of repetitions of the PRS, or a combination thereof. Using less than the full set of resources for the PRS for each beam, the mobile device may select a predetermined number of beams to be used in the tracking mode. For example, the mobile device may use signal strength metrics, such as one or more of Signal to Noise Ratio (SNR), Reference Signal Received Power (RSRP), or Reference Signal Received Quality (RSRQ), to select beams to be used in the tracking mode. In tracking mode, the mobile device tracks the PRS from the selected beams using the full set of resources for the PRS produced by each selected beam. The mobile device may perform the desired positioning measurements using the PRS from the selected beams while in tracking mode.

By using less than the full set of resources for the PRS from each beam during the acquisition mode, and using the full set of resources for the PRS only after a reduced number of beams have been selected for tracking, the mobile device may significantly reduce the power and processing requirements needed to process PRS for positioning.

FIG.1illustrates an exemplary wireless communications system100. The wireless communications system100(which may also be referred to as a wireless wide area network (WWAN)) may include various base stations102and various UEs104. The base stations102may include macro cell base stations (high power cellular base stations) and/or small cell base stations (low power cellular base stations). In an aspect, the macro cell base station may include eNBs where the wireless communications system100corresponds to an LTE network, or gNBs where the wireless communications system100corresponds to a 5G network, or a combination of both, and the small cell base stations may include femtocells, picocells, microcells, etc.

The base stations102may collectively form a RAN and interface with a core network170(e.g., an evolved packet core (EPC) or next generation core (NGC)) through backhaul links122, and through the core network170to one or more location servers172. Location server172may be internal or external to the core network170. In some implementations, the location server172may be an E-SMLC in the case of LTE access, a standalone SMLC (SAS) in the case of UMTS access, an SMLC in the case of GSM access, a SUPL Location Platform (SLP), or a Location Management Function (LMF) in the case of 5G NR access. Additionally, or alternatively, the location server may be within the RAN and may be co-located with or part of a serving base station102, which is sometimes referred to as a Location Server Surrogate (LSS)117. The LSS117may replace the location server172or may operate in conjunction with the location server172, e.g., performing some functions that would be otherwise be performed by location server172, e.g., to improve latency. In addition to other functions, the base stations102may perform functions that relate to one or more of transferring user data, radio channel ciphering and deciphering, integrity protection, header compression, mobility control functions (e.g., handover, dual connectivity), inter-cell interference coordination, connection setup and release, load balancing, distribution for non-access stratum (NAS) messages, NAS node selection, synchronization, RAN sharing, multimedia broadcast multicast service (MBMS), subscriber and equipment trace, RAN information management (RIM), paging, positioning, and delivery of warning messages. The base stations102may communicate with each other directly or indirectly (e.g., through the EPC/NGC) over backhaul links134, which may be wired or wireless.

The base stations102may wirelessly communicate with the UEs104. Each of the base stations102may provide communication coverage for a respective geographic coverage area110. In an aspect, one or more cells may be supported by a base station102in each coverage area110. A “cell” is a logical communication entity used for communication with a base station (e.g., over some frequency resource, referred to as a carrier frequency, component carrier, carrier, band, or the like), and may be associated with an identifier (e.g., a physical cell identifier (PCID), a virtual cell identifier (VCID)) for distinguishing cells operating via the same or a different carrier frequency. In some cases, different cells may be configured according to different protocol types (e.g., machine-type communication (MTC), narrowband IoT (NB-IoT), enhanced mobile broadband (eMBB), or others) that may provide access for different types of UEs. In some cases, the term “cell” may also refer to a geographic coverage area of a base station (e.g., a sector), insofar as a carrier frequency can be detected and used for communication within some portion of geographic coverage areas110.

While neighboring macro cell base station102geographic coverage areas110may partially overlap (e.g., in a handover region), some of the geographic coverage areas110may be substantially overlapped by a larger geographic coverage area110. For example, a small cell base station102′ may have a coverage area110′ that substantially overlaps with the coverage area110of one or more macro cell base stations102. A network that includes both small cell and macro cell base stations may be known as a heterogeneous network. A heterogeneous network may also include home eNBs (HeNBs), which may provide service to a restricted group known as a closed subscriber group (CSG).

The communication links120between the base stations102and the UEs104may include UL (also referred to as reverse link) transmissions from a UE104to a base station102and/or downlink (DL) (also referred to as forward link) transmissions from a base station102to a UE104. The communication links120may use MIMO antenna technology, including spatial multiplexing, beamforming, and/or transmit diversity. The communication links120may be through one or more carrier frequencies. Allocation of carriers may be asymmetric with respect to DL and UL (e.g., more or less carriers may be allocated for DL than for UL).

The wireless communications system100may further include a wireless local area network (WLAN) access point (AP)150in communication with WLAN stations (STAs)152via communication links154in an unlicensed frequency spectrum (e.g., 5 GHz). When communicating in an unlicensed frequency spectrum, the WLAN STAs152and/or the WLAN AP150may perform a clear channel assessment (CCA) prior to communicating in order to determine whether the channel is available.

The small cell base station102′ may operate in a licensed and/or an unlicensed frequency spectrum. When operating in an unlicensed frequency spectrum, the small cell base station102′ may employ LTE or 5G technology and use the same 5 GHz unlicensed frequency spectrum as used by the WLAN AP150. The small cell base station102′, employing LTE/5G in an unlicensed frequency spectrum, may boost coverage to and/or increase capacity of the access network. LTE in an unlicensed spectrum may be referred to as LTE-unlicensed (LTE-U), licensed assisted access (LAA), or MulteFire.

In 5G, the frequency spectrum in which wireless nodes (e.g., base stations102, UEs104) operate is divided into multiple frequency ranges, FR1 (from 4.1 GHz to 7.125 GHz), FR2 (from 24.25 GHz to 52.6 GHz), and FR4 (between 52.6 GHz-114.25 GHz bands). The wireless communications system100may further include a millimeter wave (mmW) base station102, which may be a small cell base station, that may operate in mmW frequencies and/or near mmW frequencies in communication with a UE104. Extremely high frequency (EHF) is part of the RF in the electromagnetic spectrum. EHF has a range of 30 GHz to 300 GHz and a wavelength between 1 millimeter and 10 millimeters. Radio waves in this band may be referred to as a millimeter wave. Near mmW may extend down to a frequency of 3 GHz with a wavelength of 100 millimeters. The super high frequency (SHF) band extends between 3 GHz and 30 GHz, also referred to as centimeter wave. Communications using the mmW/near mmW radio frequency band have high path loss and a relatively short range. The mmW base station102and the UE104may utilize beamforming (transmit and/or receive) over a mmW communication link120to compensate for the extremely high path loss and short range. Further, it will be appreciated that in alternative configurations, one or more base stations102may also transmit using mmW or near mmW and beamforming. Moreover, the mmW base station may operate in upper millimeter wave bands) e.g., between 24 GHz to 114 GHz, or some frequency allocation within that range, e.g., 24.25 GHz to 52.6 GHz or other ranges. Alternately, ultra wide bandwidth operation can also be in sub-THz frequencies (beyond either 100 GHz or 275 GHz or 300 GHz depending on how the sub-THz regime is defined). Accordingly, it will be appreciated that the foregoing illustrations are merely examples and should not be construed to limit the various aspects disclosed herein.

Transmit beamforming is a technique for focusing an RF signal in a specific direction. Traditionally, when a network node (e.g., a base station) broadcasts an RF signal, it broadcasts the signal in all directions (omni-directionally). With transmit beamforming, the network node determines where a given target device (e.g., a UE) is located (relative to the transmitting network node) and projects a stronger downlink RF signal in that specific direction, thereby providing a faster (in terms of data rate) and stronger RF signal for the receiving device(s). To change the directionality of the RF signal when transmitting, a network node can control the phase and relative amplitude of the RF signal at each of the one or more transmitters that are broadcasting the RF signal. For example, a network node may use an array of antennas (referred to as a “phased array” or an “antenna array”) that creates a beam of RF waves that can be “steered” to point in different directions, without actually moving the antennas. Specifically, the RF current from the transmitter is fed to the individual antennas with the correct phase relationship so that the radio waves from the separate antennas add together to increase the radiation in a desired direction, while cancelling to suppress radiation in undesired directions.

In receive beamforming, the receiver uses a receive beam to amplify RF signals detected on a given channel. For example, the receiver can increase the gain setting and/or adjust the phase setting of an array of antennas in a particular direction to amplify (e.g., to increase the gain level of) the RF signals received from that direction. Thus, when a receiver is said to beamform in a certain direction, it means the beam gain in that direction is high relative to the beam gain along other directions, or the beam gain in that direction is the highest compared to the beam gain in that direction of all other receive beams available to the receiver. This results in a stronger received signal strength (e.g., reference signal received power (RSRP), reference signal received quality (RSRQ), signal-to-interference-plus-noise ratio (SINR), etc.) of the RF signals received from that direction.

The wireless communications system100may further include one or more UEs, such as UE190, that connects indirectly to one or more communication networks via one or more device-to-device (D2D) peer-to-peer (P2P) links. In the example ofFIG.1, UE190has a D2D P2P link192with one of the UEs104connected to one of the base stations102(e.g., through which UE190may indirectly obtain cellular connectivity) and a D2D P2P link194with WLAN STA152connected to the WLAN AP150(through which UE190may indirectly obtain WLAN-based Internet connectivity). In an example, the D2D P2P links192and194may be supported with any well-known D2D RAT, such as LTE Direct (LTE-D), WiFi Direct (WiFi-D), Bluetooth®, and so on.

The wireless communications system100may further include a UE104that may communicate with a macro cell base station102over a communication link120and/or the mmW base station102over a mmW communication link120. For example, the macro cell base station102may support a PCell and one or more SCells for a UE and the mmW base station102may support one or more SCells for a UE.

FIG.2Aillustrates an example wireless network structure200. For example, an NGC210(also referred to as a “5GC”) can be viewed functionally as control plane functions214(e.g., UE registration, authentication, network access, gateway selection, etc.) and user plane functions212, (e.g., UE gateway function, access to data networks, IP routing, etc.) which operate cooperatively to form the core network. User plane interface (NG-U)213and control plane interface (NG-C)215connect the gNB222to the NGC210and specifically to the control plane functions214and user plane functions212. In an additional configuration, an eNB224may also be connected to the NGC210via NG-C215to the control plane functions214and NG-U213to user plane functions212. Further, eNB224may directly communicate with gNB222via a backhaul connection223. In some configurations, the New RAN220may only have one or more gNBs222, while other configurations include one or more of both eNBs224and gNBs222. Either gNB222or eNB224may communicate with UEs204(e.g., any of the UEs depicted inFIG.1). Another optional aspect may include one or more location servers230a,230b(sometimes collectively referred to as location server230) (which may correspond to location server172), which may be in communication with the control plane functions214and user plane functions212, respectively, in the NGC210to provide location assistance for UEs204. The location server230can be implemented as a plurality of separate servers (e.g., physically separate servers, different software modules on a single server, different software modules spread across multiple physical servers, etc.), or alternately may each correspond to a single server. The location server230can be configured to support one or more location services for UEs204that can connect to the location server230via the core network, NGC210, and/or via the Internet (not illustrated). Further, the location server230may be integrated into a component of the core network, or alternatively may be external to the core network, e.g., in the RAN220. Additionally, a Location Server Surrogate (LSS) (such as LSS117shown inFIG.1) may be located in the RAN220, e.g., co-located with a gNB222, and may perform one or more location management functions.

FIG.2Billustrates another example wireless network structure250. For example, an NGC260(also referred to as a “5GC”) can be viewed functionally as control plane functions, provided by an access and mobility management function (AMF)264, user plane function (UPF)262, a session management function (SMF)266, SLP268, and an LMF270, which operate cooperatively to form the core network (i.e., NGC260). User plane interface263and control plane interface265connect the ng-eNB224to the NGC260and specifically to UPF262and AMF264, respectively. In an additional configuration, a gNB222may also be connected to the NGC260via control plane interface265to AMF264and user plane interface263to UPF262. Further, eNB224may directly communicate with gNB222via the backhaul connection223, with or without gNB direct connectivity to the NGC260. In some configurations, the New RAN220may only have one or more gNB s222, while other configurations include one or more of both ng-eNB s224and gNB s222. Either ng-gNB222or eNB224may communicate with UEs204(e.g., any of the UEs depicted inFIG.1). The base stations of the New RAN220communicate with the AMF264over the N2 interface and the UPF262over the N3 interface.

The functions of the AMF include registration management, connection management, reachability management, mobility management, lawful interception, transport for session management (SM) messages between the UE204and the SMF266, transparent proxy services for routing SM messages, access authentication and access authorization, transport for short message service (SMS) messages between the UE204and the short message service function (SMSF) (not shown), and security anchor functionality (SEAF). The AMF also interacts with the authentication server function (AUSF) (not shown) and the UE204, and receives the intermediate key that was established as a result of the UE204authentication process. In the case of authentication based on a UMTS (universal mobile telecommunications system) subscriber identity module (USIM), the AMF retrieves the security material from the AUSF. The functions of the AMF also include security context management (SCM). The SCM receives a key from the SEAF that it uses to derive access-network specific keys. The functionality of the AMF also includes location services management for regulatory services, transport for location services messages between the UE204and the location management function (LMF)270(which may correspond to location server172), as well as between the New RAN220and the LMF270, evolved packet system (EPS) bearer identifier allocation for interworking with the EPS, and UE204mobility event notification. In addition, the AMF also supports functionalities for non-Third Generation Partnership Project (3GPP) access networks.

Functions of the UPF include acting as an anchor point for intra-/inter-RAT mobility (when applicable), acting as an external protocol data unit (PDU) session point of interconnect to the data network (not shown), providing packet routing and forwarding, packet inspection, user plane policy rule enforcement (e.g., gating, redirection, traffic steering), lawful interception (user plane collection), traffic usage reporting, quality of service (QoS) handling for the user plane (e.g., UL/DL rate enforcement, reflective QoS marking in the DL), UL traffic verification (service data flow (SDF) to QoS flow mapping), transport level packet marking in the UL and DL, DL packet buffering and DL data notification triggering, and sending and forwarding of one or more “end markers” to the source RAN node.

The functions of the SMF266include session management, UE Internet protocol (IP) address allocation and management, selection and control of user plane functions, configuration of traffic steering at the UPF to route traffic to the proper destination, control of part of policy enforcement and QoS, and downlink data notification. The interface over which the SMF266communicates with the AMF264is referred to as the N11 interface.

Another optional aspect may include an LMF270, which may be in communication with the NGC260to provide location assistance for UEs204. The LMF270can be implemented as a plurality of separate servers (e.g., physically separate servers, different software modules on a single server, different software modules spread across multiple physical servers, etc.), or alternately may each correspond to a single server. The LMF270can be configured to support one or more location services for UEs204that can connect to the LMF270via the core network, NGC260, and/or via the Internet (not illustrated).

FIG.3shows a block diagram of a design300of base station102and UE104, which may be one of the base stations and one of the UEs inFIG.1. Base station102may be equipped with T antennas334athrough334t, and UE104may be equipped with R antennas352athrough352r, where in general T≥1 and R≥1.

At base station102, a transmit processor320may receive data from a data source312for one or more UEs, select one or more modulation and coding schemes (MCS) for each UE based at least in part on channel quality indicators (CQIs) received from the UE, process (e.g., encode and modulate) the data for each UE based at least in part on the MCS(s) selected for the UE, and provide data symbols for all UEs. Transmit processor320may also process system information (e.g., for semi-static resource partitioning information (SRPI) and/or the like) and control information (e.g., CQI requests, grants, upper layer signaling, and/or the like) and provide overhead symbols and control symbols. Transmit processor320may also generate reference symbols for reference signals (e.g., the cell-specific reference signal (CRS)) and synchronization signals (e.g., the primary synchronization signal (PSS) and secondary synchronization signal (SSS)). A transmit (TX) multiple-input multiple-output (MIMO) processor330may perform spatial processing (e.g., precoding) on the data symbols, the control symbols, the overhead symbols, and/or the reference symbols, if applicable, and may provide T output symbol streams to T modulators (MODs)332athrough332t. Each modulator332may process a respective output symbol stream (e.g., for OFDM and/or the like) to obtain an output sample stream. Each modulator332may further process (e.g., convert to analog, amplify, filter, and upconvert) the output sample stream to obtain a downlink signal. T downlink signals from modulators332athrough332tmay be transmitted via T antennas334athrough334t, respectively. According to various aspects described in more detail below, the synchronization signals can be generated with location encoding to convey additional information.

At UE104, antennas352athrough352rmay receive the downlink signals from base station102and/or other base stations and may provide received signals to demodulators (DEMODs)354athrough354r, respectively. Each demodulator354may condition (e.g., filter, amplify, down convert, and digitize) a received signal to obtain input samples. Each demodulator354may further process the input samples (e.g., for OFDM and/or the like) to obtain received symbols. A MIMO detector356may obtain received symbols from all R demodulators354athrough354r, perform MIMO detection on the received symbols if applicable, and provide detected symbols. A receive processor358may process (e.g., demodulate and decode) the detected symbols, provide decoded data for UE104to a data sink360, and provide decoded control information and system information to a controller/processor380. A channel processor may determine reference signal received power (RSRP), received signal strength indicator (RSSI), reference signal received quality (RSRQ), channel quality indicator (CQI), and/or the like. In some aspects, one or more components of UE104may be included in a housing.

On the uplink, at UE104, a transmit processor364may receive and process data from a data source362and control information (e.g., for reports comprising RSRP, RSSI, RSRQ, CQI, and/or the like) from controller/processor380. Transmit processor364may also generate reference symbols for one or more reference signals. The symbols from transmit processor364may be precoded by a TX MIMO processor366if applicable, further processed by modulators354athrough354r(e.g., for DFT-s-OFDM, CP-OFDM, and/or the like), and transmitted to base station102. At base station102, the uplink signals from UE104and other UEs may be received by antennas334, processed by demodulators332, detected by a MIMO detector336if applicable, and further processed by a receive processor338to obtain decoded data and control information sent by UE104. Receive processor338may provide the decoded data to a data sink339and the decoded control information to controller/processor340. Base station102may include communication unit344and communicate to a network controller, such as location server172via communication unit344, which may include one or more intervening elements. Location server172may include communication unit394, controller/processor390, and memory392.

Controller/processor340of base station102, controller/processor380of UE104, controller390of location server172, which may be location server172, and/or any other component(s) ofFIG.3may perform one or more techniques as described in more detail elsewhere herein. For example, controller/processor380of UE104, controller390of location server172, controller/processor340of base station102, and/or any other component(s) ofFIG.3may perform or direct operations of, for example, processes900and1600ofFIGS.9and16, and/or other processes as described herein. Memories342,382, and392may store data and program codes for base station102, UE104, and location server172, respectively. In some aspects, memory342and/or memory382and/or memory392may comprise a non-transitory computer-readable medium storing one or more instructions for wireless communication. For example, the one or more instructions, when executed by one or more processors of the UE104, location server172, and/or base station102, may perform or direct operations of, for example, processes900and1600ofFIGS.9and16and/or other processes as described herein. A scheduler346may schedule UEs for data transmission on the downlink and/or uplink.

As indicated above,FIG.3is provided as an example. Other examples may differ from what is described with regard toFIG.3.

In particular implementations, the UE104may have circuitry and processing resources capable of obtaining location related measurements (also referred to as location measurements), such as measurements for signals received from GPS or other Satellite Positioning Systems (SPS's), measurements for cellular transceivers such as base stations102, and/or measurements for local transceivers. UE104may further have circuitry and processing resources capable of computing a position fix or estimated location of UE104based on these location related measurements. In some implementations, location related measurements obtained by UE104may be transferred to a location server, such as the location server172, location servers230a,230b, or LMF270, after which the location server may estimate or determine a location for UE104based on the measurements.

Location related measurements obtained by UE104may include measurements of signals received from satellite vehicles (SVs) that are part of an SPS or Global Navigation Satellite System (GNSS) such as GPS, GLONASS, Galileo or Beidou and/or may include measurements of signals received from terrestrial transmitters fixed at known locations (e.g., such as base station102or other local transceivers). UE104or a separate location server (e.g. location server172) may then obtain a location estimate for the UE104based on these location related measurements using any one of several position methods such as, for example, GNSS, Assisted GNSS (A-GNSS), Advanced Forward Link Trilateration (AFLT), Time Difference Of Arrival (TDOA), Enhanced Cell ID (ECID), TDOA, AoA, AoD, multi-RTT, or combinations thereof. In some of these techniques (e.g. A-GNSS, AFLT and TDOA), pseudoranges or timing differences may be measured by UE104relative to three or more terrestrial transmitters fixed at known locations or relative to four or more SVs with accurately known orbital data, or combinations thereof, based at least in part, on pilot signals, positioning reference signals (PRS) or other positioning related signals transmitted by the transmitters or SVs and received at the UE104. Here, location servers, such as location server172, location servers230a,230b, or LMF270may be capable of providing positioning assistance data to UE104including, for example, information regarding signals to be measured by UE104(e.g., expected signal timing, signal coding, signal frequencies, signal Doppler), locations and/or identities of terrestrial transmitters, and/or signal, timing and orbital information for GNSS SVs to facilitate positioning techniques such as A-GNSS, AFLT, TDOA, AoA, AoD, multi-RTT, and ECID. The facilitation may include improving signal acquisition and measurement accuracy by UE104and/or, in some cases, enabling UE104to compute its estimated location based on the location measurements. For example, a location server may comprise an almanac (e.g., a Base Station Almanac (BSA)) which indicates the locations and identities of cellular transceivers and transmitters (e.g. base stations102) and/or local transceivers and transmitters in a particular region or regions such as a particular venue, and may further contain information descriptive of signals transmitted by these transceivers and transmitters such as signal power, signal timing, signal bandwidth, signal coding and/or signal frequency. In the case of ECID, a UE104may obtain measurements of signal strength (e.g. received signal strength indication (RSSI) or reference signal received power (RSRP)) for signals received from cellular transceivers (e.g., base stations102) and/or local transceivers and/or may obtain a signal to noise ratio (S/N), a reference signal received quality (RSRQ), or a round trip signal propagation time (RTT) between UE104and a cellular transceiver (e.g., base stations102) or a local transceiver. A UE104may transfer these measurements to a location server, to determine a location for UE104, or in some implementations, UE104may use these measurements together with positioning assistance data (e.g. terrestrial almanac data or GNSS SV data such as GNSS Almanac and/or GNSS Ephemeris information) received from the location server to determine a location for UE104.

An estimate of a location of a UE104may be referred to as a location, location estimate, location fix, fix, position, position estimate or position fix, and may be geodetic, thereby providing location coordinates for the UE104(e.g., latitude and longitude) which may or may not include an altitude component (e.g., height above sea level, height above or depth below ground level, floor level or basement level). Alternatively, a location of the UE104may be expressed as a civic location (e.g., as a postal address or the designation of some point or small area in a building such as a particular room or floor). A location of a UE104may also include an uncertainty and may then be expressed as an area or volume (defined either geodetically or in civic form) within which the UE104is expected to be located with some given or default probability or confidence level (e.g., 67% or 95%). A location of a UE104may further be an absolute location (e.g. defined in terms of a latitude, longitude and possibly altitude and/or uncertainty) or may be a relative location comprising, for example, a distance and direction or relative X, Y (and Z) coordinates defined relative to some origin at a known absolute location. In the description contained herein, the use of the term location may comprise any of these variants unless indicated otherwise. Measurements (e.g. obtained by UE104or by another entity such as base station102) that are used to determine (e.g. calculate) a location estimate for UE104may be referred to as measurements, location measurements, location related measurements, positioning measurements or position measurements and the act of determining a location for the UE104may be referred to as positioning of the UE104or locating the UE104.

FIG.4shows a structure of an exemplary subframe sequence400with positioning reference signal (PRS) positioning occasions. Subframe sequence400may be applicable to the broadcast of PRS signals from a base station (e.g., any of the base stations described herein) or other network node. The subframe sequence400may be used in LTE systems, and the same or similar subframe sequence may be used in other communication technologies/protocols, such as 5G NR. For example, with 5G NR, the resource grid is nearly identical to that used with LTE, but the physical dimensions, e.g., subcarrier spacing, number of OFDM symbols within a radio frame) varies in NR depending on the numerology.

InFIG.4, time is represented horizontally (e.g., on the X axis) with time increasing from left to right, while frequency is represented vertically (e.g., on the Y axis) with frequency increasing (or decreasing) from bottom to top. As shown inFIG.4, downlink and uplink radio frames410may be of 10 millisecond (ms) duration each. For downlink frequency division duplex (FDD) mode, radio frames410are organized, in the illustrated example, into ten subframes412of 1 ms duration each. Each subframe412comprises two slots414, each of, for example, 0.5 ms duration.

In the frequency domain, the available bandwidth may be divided into uniformly spaced orthogonal subcarriers416(also referred to as “tones” or “bins”). For example, for a normal length cyclic prefix (CP) using, for example, 15 kHz spacing, subcarriers416may be grouped into a group of twelve (12) subcarriers. A resource of one OFDM symbol length in the time domain and one subcarrier in the frequency domain (represented as a block of subframe412) is referred to as a resource element (RE). Each grouping of the 12 subcarriers416and the 14 OFDM symbols is termed a resource block (RB) and, in the example above, the number of subcarriers in the resource block may be written as NSCRB=12. For a given channel bandwidth, the number of available resource blocks on each channel422, which is also called the transmission bandwidth configuration422, is indicated as NRBDL. For example, for a 3 MHz channel bandwidth in the above example, the number of available resource blocks on each channel422is given by NRBDL=15. Note that the frequency component of a resource block (e.g., the 12 subcarriers) is referred to as a physical resource block (PRB).

A base station may transmit radio frames (e.g., radio frames410), or other physical layer signaling sequences, supporting PRS signals (i.e. a downlink (DL) PRS) according to frame configurations either similar to, or the same as that, shown inFIG.4, which may be measured and used for a UE (e.g., any of the UEs described herein) position estimation. Other types of wireless nodes (e.g., a distributed antenna system (DAS), remote radio head (RRH), UE, AP, etc.) in a wireless communications network may also be configured to transmit PRS signals configured in a manner similar to (or the same as) that depicted inFIG.4.

A collection of resource elements that are used for transmission of PRS signals is referred to as a “PRS resource.” The collection of resource elements can span multiple PRBs in the frequency domain and N (e.g., 1 or more) consecutive symbol(s) within a slot414in the time domain. For example, the cross-hatched resource elements in the slots414may be examples of two PRS resources. A “PRS resource set” is a set of PRS resources used for the transmission of PRS signals, where each PRS resource has a PRS resource identifier (ID). In addition, the PRS resources in a PRS resource set are associated with the same transmission-reception point (TRP). A PRS resource ID in a PRS resource set is associated with a single beam transmitted from a single TRP (where a TRP may transmit one or more beams). Note that this does not have any implications on whether the TRPs and beams from which signals are transmitted are known to the UE.

PRS may be transmitted in special positioning subframes that are grouped into positioning occasions. A PRS occasion is one instance of a periodically repeated time window (e.g., consecutive slot(s)) where PRS are expected to be transmitted. Each periodically repeated time window can include a group of one or more consecutive PRS occasions. Each PRS occasion can comprise a number NPRSof consecutive positioning subframes. The PRS positioning occasions for a cell supported by a base station may occur periodically at intervals, denoted by a number TPRSof milliseconds or subframes. As an example,FIG.4illustrates a periodicity of positioning occasions where NPRSequals 4418and TPRSis greater than or equal to 20420. In some aspects, TPRSmay be measured in terms of the number of subframes between the start of consecutive positioning occasions. Multiple PRS occasions may be associated with the same PRS resource configuration, in which case, each such occasion is referred to as an “occasion of the PRS resource” or the like.

A PRS may be transmitted with a constant power. A PRS can also be transmitted with zero power (i.e., muted). Muting, which turns off a regularly scheduled PRS transmission, may be useful when PRS signals between different cells overlap by occurring at the same or almost the same time. In this case, the PRS signals from some cells may be muted while PRS signals from other cells are transmitted (e.g., at a constant power). Muting may aid signal acquisition and time of arrival (TOA) and reference signal time difference (RSTD) measurement, by UEs, of PRS signals that are not muted (by avoiding interference from PRS signals that have been muted). Muting may be viewed as the non-transmission of a PRS for a given positioning occasion for a particular cell. Muting patterns (also referred to as muting sequences) may be signaled (e.g., using the LTE positioning protocol (LPP)) to a UE using bit strings. For example, in a bit string signaled to indicate a muting pattern, if a bit at position j is set to ‘0’, then the UE may infer that the PRS is muted for a jthpositioning occasion.

To further improve hearability of PRS, positioning subframes may be low-interference subframes that are transmitted without user data channels. As a result, in ideally synchronized networks, PRS may be interfered with by other cells' PRS with the same PRS pattern index (i.e., with the same frequency shift), but not from data transmissions. The frequency shift may be defined as a function of a PRS ID for a cell or other transmission point (TP) (denoted as NIDPRS) or as a function of a physical cell identifier (PCI) (denoted as NIDcell) if no PRS ID is assigned, which results in an effective frequency re-use factor of six (6).

To also improve hearability of a PRS (e.g., when PRS bandwidth is limited, such as with only six resource blocks corresponding to 1.4 MHz bandwidth), the frequency band for consecutive PRS positioning occasions (or consecutive PRS subframes) may be changed in a known and predictable manner via frequency hopping. In addition, a cell supported by a base station may support more than one PRS configuration, where each PRS configuration may comprise a distinct frequency offset (vshift), a distinct carrier frequency, a distinct bandwidth, a distinct code sequence, and/or a distinct sequence of PRS positioning occasions with a particular number of subframes (NPRS) per positioning occasion and a particular periodicity (TPRS) In some implementation, one or more of the PRS configurations supported in a cell may be for a directional PRS and may then have additional distinct characteristics, such as a distinct direction of transmission, a distinct range of horizontal angles, and/or a distinct range of vertical angles.

A PRS configuration, as described above, including the PRS transmission/muting schedule, is signaled to the UE to enable the UE to perform PRS positioning measurements. The UE is not expected to blindly perform detection of PRS configurations.

FIG.5illustrates nine different DL positioning reference signal (PRS) frame structure options available in 5G NR, where each PRS frame structure inFIG.5illustrates the transmission of a DL PRS with a shaded square. A DL PRS resource may span within a slot 2, 4, 6, 12 consecutive symbols with a staggered pattern of 2, 4, 6, or 12 in the frequency-domain. The PRS frame structures are identified with the number of symbols of the subframe in each sub-carrier, during which PRS are transmitted. The term “symbol” is well defined in LTE and NR as a collection of sub-carriers transmitted over some common and fixed time duration. The PRS frame structures are further identified with the staggering of the frequency of transmission in each symbol, referred to as Comb. For example, the top left PRS frame structure uses 2 symbols (with a DL-PRS-ResourceSymbolOffset of 3), where only every other sub-carrier is utilized within each symbol, i.e., Comb-2. The bottom left PRS frame structure uses 6 symbols (DL-PRS-ResourceSymbolOffset of 2), and only every sixth sub-carrier is utilized within each symbol, i.e., Comb-6. Thus, the top row ofFIG.5illustrate three PRS frame structures with 2, 4, and 6 symbols, all of which have a Comb 2 structure, the middle row illustrates three PRS frame structures having 12, 4, and 12 symbols and having Comb-2, Comb-4 and Comb-4 structures, respectively, and the bottom row illustrates three PRS frame structures with 6, 12, and 12 symbols having Comb-6, Comb-6, and Comb-12 structures, respectively.

Thus, for each transmitted PRS, the PRS is repeated over a number of subframes in each positioning occasion. Additionally, the PRS is transmitted with a bandwidth that is the full frequency spectrum, e.g., all subcarrier frequencies. During reception of the PRS, the UE104tunes the radio signal receiver to the bandwidth of the PRS and receives, processes, and integrates over all repetitions of the PRS to produce the PRS measurement for the sub-frame or frame.

FIG.6illustrates an example of narrow beams that may be produced by an antenna panel602for a base station102. The antenna panel602includes a number of separate antennas which are provided RF current from the transmitter with the correct phase relationship so that the radio waves from the separate antennas add together to increase the radiation in a desired direction, while cancelling to suppress radiation in undesired directions, to produce a beam. The beam can be steered to point in different directions, e.g., changing the azimuth angle and elevation angle, without moving the antenna panel602.FIG.6, for example, illustrates the antenna panel602in the center of a sphere600showing azimuth angles from 0°, ±90°, to 180°, and elevation angles from 0°, ±90°, to 180°. The antenna panel602may be controlled to produce beams at various angles, illustrated as beams604,606, and608. In general, the antenna panel602may produce an azimuth span of 120° and an elevation span of 60°. By increasing the number of individual antennas present in the antenna panel602, the width of the beams produced may be reduced. Initial link acquisition at base stations may be performed over beamformed transmissions in Secondary Synchronization Blocks (SSBs). Beam refinement beyond the SSB stage is either performed over channel state information reference signals (CSI-RSs) or sounding reference signals (SRSs). These stages lead to refined beams at both the base station and user ends. Each beam transmitted by a base station may include PRS.

FIG.7, by way of example, illustrates a positioning procedure700performed by a UE104and a base station102using PRS in transmit beams. The base station102, which may be a gNB, transmits PRS resources in a beam-sweeping manner, illustrated as beams702,704, and706, labeled as PRS #1, PRS #2, and PRS #3, respectively. The UE104may receive one or more PRS resource in beams702,704, and706, using a beamformed receive beam712. For example, in time based positioning procedures, such as TDOA, RTT, etc., the UE104may use PRS received in a plurality of beams, while angle based measurements, such as AoD, the PRS706most closely aligned with the line of sight (LOS)710between the base station102and the UE104may be used. During positioning measurements, PRS received from more than one base station may be used.

In UE-assisted mode, the UE104may report the positioning measurement for one or more received PRS through LPP protocol to the location server, e.g., location server172, which may calculate an estimated position of the UE104. In UE-based mode, the UE104may use assistance data provided by the location server172, which may include positioning information such as the positions of base stations, along with the positioning measurements, to calculate an estimated position of the UE104.

Relative to LTE PRS implementations, the flexibility in PRS signaling provided in 5G NR, including multiple symbol and Comb options per subframe, repetitions of the PRS transmission in multiple subframes, and on multiple beams, significantly increases the processing, e.g., million instructions per second (MIPS), memory, and power requirements. For example, Table 1 below illustrates the processing requirements for once cell for different technologies that use different configurations, e.g., illustrated as resource blocks (RBs), Inverse Fourier Fast Transform (IFFT) operations, and number of beams.

Multiplier-Accumulator(MAC)TechnologyoperationsNormalizedConfigurationLTE203601100 RB, IFFT = 20485G-FR163027230.9272 RB, IFFT = 8192,beam = 85G-FR24954112243.3264 RB, IFFT = 8192,beam = 64TABLE 1

As can be seen in Table 1, the requirements for processing PRS, and thus, the required power, for 5G FR1 or 5G FR2 is significantly greater than processing PRS with LTE.

FIG.8, by way of example, is a graph800illustrating8transmission beams B1, B2, B3, B4, B5, B6, B7, and B8produced by a base station in FR1. Each beam includes PRS provided over multiple positioning occasions, e.g., at 0, 160, 320, 480, 640, and 800 ms. Each PRS occasion includes 1 subframe (NPRS=1) of PRS and two repetitions, i.e., the number of times the PRS resource (subframe) is transmitted (which may be between, e.g., 1 and 32), illustrated as two bars in each positioning occasion. By way of example, the PRS may use the two symbols with Comb-2 option and may have 272 resource blocks (RBs), and require 4 k, 8 k, or 16 k operations, depending on the performance requirements. With this configuration, for a single cell, the UE needs to decode 2 symbol*8 beam*beam repetitions*NPRS, over the full bandwidth of the PRS, which is a large processing requirement, particularly if the PRS BW is high.

As illustrated inFIG.8in the first positioning occasion, the UE104may process all 8 beams over the full set of resources used by the PRS on each beam, including the full bandwidth and the full number of repetitions. The UE104may select the best beams amongst the 8 beams and in future positioning occasions may process only the selected beams, e.g., beams B1, B5, and B6, for the remaining positioning occasions, e.g., at 160, 320, 480, 640, and 800 ms. Even though a reduced number of beams are processed in subsequent positioning occasions, the processor and power requirements for processing the PRS over the full set of resources available for the PRS on each beam may be exceedingly large and it is desirable to reduce the processing requirements.

Accordingly, in one implementation, the UE104may divide the PRS processing into two separate modes, e.g., an acquisition mode and a tracking mode. During the acquisition mode, the UE104performs a fast scan of all of the beams from a base station102transmitting PRS using less than the full set of resources for the PRS, while in the tracking mode the UE104processes the full set of resources for the PRS, but for a reduced number of beams.

FIG.9is a flow chart illustrating a positioning process900that may be employed by the UE104in which the PRS processing is divided into two separate modes, e.g., an acquisition mode and a tracking mode.

As illustrated at block902, a determination is made whether the UE104is in acquisition mode or tracking mode. Acquisition mode901, for example, is performed during an initial positioning occasion or after being in tracking mode for a predetermined number of occasions or there is an indication that the selection of beams from the initial acquisition may no longer be valid, e.g., if there is an indication that the UE104may have moved or conditions have changed.

At block904, the UE104initializes the set of resources that will be used for processing the PRS for each beam in the acquisition mode901. The set of resources used in acquisition mode901is less than the full set of resources for the PRS produced by each beam. The UE104, for example, may be aware of the full set of resources for the PRS for each beam, including the full bandwidth and full number of repetitions, through assistance data received from the location server172. The UE104may initialize the set of resources by selecting a fraction of the full bandwidth, a fraction of the full number of repetitions, or a combination thereof, to be used for receiving and processing the PRS. By way of example, the UE104may select to use ½, ¼, ⅛, 1/16, etc., of the full bandwidth. The receiver, for example may be tuned to receive a fraction of the full bandwidth of the PRS while in acquisition mode. Similarly, the UE104may additionally or alternatively select to use a fraction or some portion of the full number of repetitions, e.g., ½, ⅓, ⅔, ¼, ¾ etc., as long as at least one repetition (e.g., one PRS resource) is transmitted. For example, where there are 2 repetitions, i.e., the PRS resource is transmitted two times, the UE104may select to use 1 repetition (only the initial PRS resource is transmitted) or 2 repetitions, while if there are 4 repetitions, the UE104may select to use 1, 2, 3, or 4 repetitions, where the resulting number of transmitted PRS resources is a whole number, i.e., in the time domain, at least one complete PRS resource (subframe) is transmitted. The processors in the UE104, thus, may be configured to receive and integrate over less than the full number of repetitions of the PRS while in acquisition mode.

At block906, the UE104receives and processes the PRS signals according to the initialized set of resources and determines a signal strength metric for each beam in the plurality of beams. For example, the UE104may receive the PRS by tuning the radio signal receiver to the initialized fraction of the full bandwidth for the PRS on each beam, e.g., ¼ of the full bandwidth of the PRS. The UE104may additionally or alternatively receive and integrate over the fraction of the full number of repetitions for the PRS on each beam, e.g., 1, ½, ⅓, or ¼ of the full number of repetitions in the PRS. The UE104may measure one or more signal strength metrics, such as SNR, RSRP, or RSRQ for the received PRS for each beam. For example, in one implementation, the channel energy response may be calculated and used to determine the peak SNR.

FIG.10, by way of example, illustrates a graph1000of a simulated channel energy response (CER) for PRS that is processed using different fractions of the full set of resources (different fractions of the full bandwidth). For example, graph1000illustrates the CER1002for a PRS with 68 RBs and 2048 IFFT (corresponding to a ¼ of the bandwidth), a CER1004for a PRS with 138 RB and 4096 IFFT (corresponding to a ½ of the bandwidth), and a CER1006for a PRS with 272 RB and 8192 IFFT (corresponding to the full bandwidth). The noise floors1012,1014and1016associated with each of the CERs1002,1004, and1006, respectively is also illustrated. The peak SNR is determined based on the difference between the CER value at tap 0 and the noise floor. For example, CER1002has a peak SNR of 29 dB, CER1004has a peak SNR of 32 dB, and CER1006has a peak SNR of 35 dB. Thus, as can be seen, by reducing the set of resources used to process the PRS, there is a measurable performance loss in the peak SNR. For example, there is an approximate 3 dB loss for every half bandwidth reduction. Similarly, reducing the set of resources used to process the PRS results in a measurable performance loss in other signal strength metrics, such as RSRP, or RSRQ.

Referring back toFIG.9, at block908, the one or more signal strength metrics for each beam (i) may be compared to predetermined thresholds corresponding to the one or more signal strength metrics to determine if a predetermined number M of beams have signal strength metrics that exceed the predetermined thresholds and whether less than the full set of resources were used to process the PRS. The predetermined threshold used for the comparison to the signal strength metrics may be empirically selected based on the sensitivity of the radio signal receiver. For example, referring toFIG.10, in some implementations, an SNR threshold of 25 dB may be used with some devices, but other thresholds may be used, e.g., in a range of 15 to 25. The beams having signal strength metrics that exceed the predetermined thresholds are considered the best beams and are selected to be used for positioning and to be used during the tracking mode. The number M of beams selected may be based on the type of positioning measurement being performed. For example, a timing based measurement may use multiple beams, e.g., 3 beams, while an angle based measurement may use a single beam, e.g., the beam presumably closest so the line of sight.

If in block908, it is determined that the predetermined number M of beams have signal strength metrics that meet the requisite threshold(s), then the process flows to block910and the PRS from the selected beams are processed for positioning, before returning to block902.

In block908, however, it may be determined that fewer than (or more than) the predetermined number M of beams have signal strength metrics that meet the requisite threshold(s), and the fraction of the full set of resources used in the acquisition mode to process the PRS may be increased (or decreased) accordingly. For example, if in block908it is determined that less than the predetermined number M of beams may be selected, e.g., fewer than the predetermined number of beams have signal strength metrics that exceed the predetermined threshold(s), the process flows to block912and the fraction of the full set of resources for the PRS is increased, e.g., doubled or otherwise increased, and the acquisition mode is repeated. For example, in the next positioning occasion the increased set of resources is used to process the PRS from each beam and one or more signal strength metrics are determined (906) and compared to corresponding thresholds. The process is repeated until the predetermined number M of beams have signal strength metrics that meet the requisite threshold(s) or the full set of resources were used, and thus, a further increase in resources used to process the PRS is not possible.

Alternatively, if in block908it is determined that more than the predetermined number of beams have signal strength metrics that meet the requisite threshold(s), then only the predetermined number M of beams are selected (e.g., the first M beams having signal strength metrics that meet the requisite threshold(s)) and the process flows to block910. The next time the UE104is in acquisition mode901, which may be after a predetermined number of positioning occasions or an indication that the initial selection of beams is no longer valid, or in some implementations, in the next positioning occasion, the fraction of the full set of resources for the PRS may be decreased (e.g., halved) and the acquisition mode901repeated until only the predetermined number M of beams have signal strength metrics that meet the requisite threshold(s).

Once the predetermined number M of beams have been selected during the acquisition mode, at the next positioning occasion, the process900goes into tracking mode903via block902. In tracking mode903, the UE104receives and processes the PRS from the selected beams using the full set of resources for the PRS produced by each selected beam. For example, at block920in the tracking mode, the UE104selects the best M beams for tracking, as determined in the acquisition mode901. At block922, the PRS from the selected beams are received and processed for positioning using the full set of resources for the PRS in each selected beam. Thus, the receiver may be tuned to receive the full bandwidth of the PRS while in tracking mode and the processors may be configured to receive and integrate over the full number of repetitions of the PRS while in tracking mode.

The UE104may return to the acquisition mode901after a predetermined number of positioning occasions in tracking mode903. The UE104may also or alternatively return to the acquisition mode if a difference in the signal strength metrics for the selected beams over multiple positioning occasions indicates that the selection of beams from the initial acquisition mode901is no longer valid, e.g., the UE104has significantly moved and/or conditions have changed. For example, at each positioning occasion, one or more signal strength metrics, e.g., SNR, RSRP, RSRQ, etc., for the selected beams may be compared to measured signal strength metrics from one or more preceding positioning occasions, e.g., the measured signal strength metrics from the immediately preceding positioning occasion, the measured signal strength metrics from the first positioning occasion used in tracking mode903, or an average (or other (statistical combination) of the measured signal strength metrics from a plurality of positioning occasions used in tracking mode903. If the difference between the signal strength metrics exceeds a predetermined threshold, the UE104may have moved or conditions may have changed and the initially selected beams may no longer be the best beams. Accordingly, the process900may then return to the acquisition mode901at block902.

FIGS.11A and11B, by way of example, are graphs1100and1150that illustrate8transmission beams B1, B2, B3, B4, B5, B6, B7, and B8produced by a base station in FR1. Similar toFIG.8, each beam includes PRS provided over multiple positioning occasions, e.g., at 0, 160, 320, 480, 640, and 800 ms. Each PRS occasion includes 1 subframe (NPRS=1) of PRS and two repetitions, illustrated as two bars in each positioning occasion. The PRS may use the two symbols with Comb-2 option and may have 272 resource blocks (RBs), and may require 4 k, 8 k, or 16 k operations, depending on the performance requirements. UnlikeFIG.8, inFIGS.11A and11B, the UE104operates in an acquisition mode (block901ofFIG.9) during the first positioning occasion, e.g., at 0 ms, during which the UE104receives and processes the PRS for each beam using less than the full set of resources, and operates in a tracking mode (block903ofFIG.9) during the remaining positioning occasions, e.g., 160, 320, 480, 640, and 800 ms, during which the UE104receives and processes the PRS for each beam using the full set of resources. Two sets of acquisition and tracking are illustrated inFIGS.11A and11B.

InFIG.11Athe UE104operates in acquisition mode (block901ofFIG.9) by receiving and processing the PRS for each beam using half of the full bandwidth of the PRS for each beam, which is illustrated by the relatively shorter bars in the positioning occasion at 0 ms. By way of example, beams B1, B5, and B6may be selected as the best beams for positioning measurements during the acquisition mode in the first positioning occasion, e.g., based on one or more signal strength metrics that meet the requisite threshold(s). In the tracking mode (block903ofFIG.9) in subsequent positioning occasions, e.g., at 160, 320, 480, 640, and 800 ms, the PRS from beams B1, B5, and B6are received and processed using the full set of resources, e.g., the full bandwidth of the PRS for each beam, as illustrated by the relatively longer bars, for the positioning measurements.

FIG.11Bthe UE104operates in acquisition mode (block901ofFIG.9) by receiving and processing the PRS for each beam using 1 repetition of the PRS for each beam at 0 ms, which is illustrated by the presence of only 1 bar in the positioning occasion at 0 ms. By way of example, beams B1, B5, and B6may be selected as the best beams for positioning measurements during the acquisition mode during the first positioning occasion, e.g., based on one or more signal strength metrics that meet the requisite threshold(s). In the tracking mode (block903ofFIG.9) in subsequent positioning occasions, e.g., at 160, 320, 480, 640, and 800 ms, the PRS from beams B1, B5, and B6are received and processed using the full set of resources, e.g., the full number of repetitions of the PRS for each beam, as illustrated by the presence of two bars, for the positioning measurements.

FIGS.11A and11Billustrate a second set of acquisition and tracking modes, where the first positioning occasion (e.g., 0 ms) uses less than the full set of resources during acquisition mode and the remaining positioning occasions use the full set of resources during tracking mode. By way of example, the UE104may return to acquisition mode (block901ofFIG.9), after a predetermined number of positioning occasions or if the signal strength metrics for one or more of the beams B1, B5, and B6in the positioning occasion at 800 ms changes by more than a predetermined threshold, e.g., relative to one or more preceding positioning occasions during the tracking mode. After the second acquisition mode,FIGS.11A and11Billustrate that beams B2, B5and B7are selected for positioning measurements, e.g., based on one or more signal strength metrics that meet the requisite threshold(s).

FIG.12, by way of example, is a graph1200that illustrates8transmission beams B1, B2, B3, B4, B5, B6, B7, and B8produced by a base station in FR1. Similar toFIG.11A, each beam includes PRS provided over multiple positioning occasions, e.g., at 0, 160, 320, 480, 640, and 800 ms. Each PRS occasion includes 1 subframe (NPRS=1) of PRS and two repetitions, illustrated as two bars in each positioning occasion. The PRS may use the two symbols with Comb-2 option and may have 272 resource blocks (RBs), and require 4 k, 8 k, or 16 k operations, depending on the performance requirements. Two sets of acquisition and tracking are illustrated inFIG.12.

InFIG.12, the UE104operates in acquisition mode (block901ofFIG.9) by receiving and processing the PRS for each beam using a quarter of the full bandwidth of the PRS for each beam, which is illustrated by the relatively shorter bars in the positioning occasion at 0 ms. In this example, fewer than the predetermined number of beams (3) have signal strength metrics that exceed the predetermined thresholds (block908ofFIG.9), illustrated with the dashed boxes around beams B1and B4. Accordingly, the fraction of the full set of resources for the PRS is increased, e.g., doubled, in the next positioning occasion (block912ofFIG.9). In the second positioning occasion at 160 ms, the acquisition mode is repeated using half of the full bandwidth of the PRS for each beam. With half of the full bandwidth of the PRS for each beam used the predetermined number (3) of beams have signal strength metrics that exceed the predetermined thresholds, as illustrated with the dashed boxes for beams B1, B4, and B6during the second positioning occasion at 160 ms. Accordingly, the UE104may select the beams B1, B4, and B6for the positioning measurements. During the tracking mode (block903ofFIG.9) in the subsequent positioning occasions, e.g., at 320, 480, 640, and 800 ms, the PRS from beams B1, B4, and B6are received and processed using the full set of resources, e.g., the full bandwidth of the PRS for each beam, for the positioning measurements. In an implementation where a reduced number of repetitions is used during acquisition mode (e.g., as illustrated inFIG.11B), if fewer than the predetermined number of beams (3) have signal strength metrics that exceed the predetermined thresholds the number of repetitions may be increased, e.g., doubled, increased incrementally, or otherwise increased, in the next positioning occasion (block912ofFIG.9).

In a subsequent set of acquisition and tracking, e.g., after a predetermined number of positioning occasions during the tracking mode or an indication that the UE104has moved or conditions have changed, the UE104may use the set of resources that successfully identified the predetermined number (3) beams, i.e., half of the full bandwidth of the PRS for each beam.

FIG.13, by way of example, is a graph1300that illustrates8transmission beams B1, B2, B3, B4, B5, B6, B7, and B8produced by a base station in FR1. Similar toFIG.11A, each beam includes PRS provided over multiple positioning occasions, e.g., at 0, 160, 320, 480, 640, and 800 ms. Each PRS occasion includes 1 subframe (NPRS=1) of PRS and two repetitions, illustrated as two bars in each positioning occasion. The PRS may use the two symbols with Comb-2 option and may have 272 resource blocks (RBs), and require 4 k, 8 k, or 16 k operations, depending on the performance requirements. Two sets of acquisition and tracking are illustrated inFIG.13.

InFIG.13, the UE104operates in acquisition mode (block901ofFIG.9) by receiving and processing the PRS for each beam using half of the full bandwidth of the PRS for each beam. In this example, more than the predetermined number of beams (3) have signal strength metrics that exceed the predetermined thresholds (block908ofFIG.9), illustrated with the dashed boxes on beams B1, B4, B5, and B6. Accordingly, a predetermined number of beams (e.g., the first M beams), illustrated as beams B1, B2, and B5, may be selected as the best beams for the positioning measurements and are used in the tracking mode in positioning occasions 160, 320, 480, 640, 800 ms.

In the next acquisition mode, e.g., as illustrated at 0 ms in the second set of positioning occasions, the UE104decreases the resources used to receive and process the PRS for each beam, e.g., as illustrated as using a quarter of the full bandwidth of the PRS for each beam. In this example, using reduced resources in the second acquisition mode, the predetermined number of beams (3) have signal strength metrics that exceed the predetermined thresholds (block908ofFIG.9), illustrated with the dashed boxes on beams B1, B4, and B6. The selected beams may then be used for the positioning measurements and the tracking mode in positioning occasions 160, 320, 480, 640, 800 ms.

FIGS.14A and14Billustrate graphs1400and1450showing the savings in multiplier—accumulator (MAC) operations for a cell transmitting 8 beams in FR1, and a cell transmitting 64 beams in FR2, respectively. As illustrated inFIG.14A, as illustrated with bars1402, the total MACs used to acquire PRS for RSTD over 272 RB (e.g., the full set of resources over all 8 beams) vs MACs used to acquire PRS for RSTD over 272 RB (e.g., the full set of resources over 3 beams) drops from 630,272 to 241,472. As illustrated with bars1404, the total MACs used to acquire PRS for RSTD over 136 RB (e.g., half of the resources over all 8 beams) vs MACs used to acquire PRS for RSTD over 272 RB (e.g., the full set of resources over 3 beams) drops from 298,752 to 241,472. As illustrated with bars1406, the total MACs used to acquire PRS for RSTD over 68 RB (e.g., a quarter of the resources over all 8 beams) vs MACs used to acquire PRS for RSTD over 272 RB (e.g., the full set of resources over 3 beams) increases from 141,184 to 241,472. The processing savings (power savings) for the acquisition mode are illustrated in Table 2.

TABLE 2272 RB136 RB68 RBMAC Operations630,272298,752141,184Percent Savings100%47.4%22.4%

As illustrated inFIG.14A, as illustrated with bars1452, the total MACs used to acquire PRS for RSTD over 264 RB (e.g., the full set of resources over all 64 beams) vs MACs used to acquire PRS for RSTD over 264 RB (e.g., the full set of resources over 3 beams) drops from 4,954,112 to 708,032. As illustrated with bars1454, the total MACs used to acquire PRS for RSTD over 132 RB (e.g., half of the resources over all 64 beams) vs MACs used to acquire PRS for RSTD over 264 RB (e.g., the full set of resources over 3 beams) drops from 2,345,984 to 708,032. As illustrated with bars1456, the total MACs used to acquire PRS for RSTD over 68 RB (e.g., a quarter of the resources over all 64 beams) vs MACs used to acquire PRS for RSTD over 264 RB (e.g., the full set of resources over 3 beams) decreases from 1,115,136 to 708,032. The processing savings (power savings) for the acquisition mode are illustrated in Table 3.

TABLE 3264 RB132 RB68 RBMAC Operations4,954,1122,345,9841,115,136Percent Savings100%47.3%22.5%

Thus, as can be seen inFIGS.14A and14Band Tables 2 and 3, the UE104may receive a significant processing/power savings in acquisition mode using less than all of the resources for the PRS and the gains are more pronounced using smaller fractions of the full set of resources.

FIG.15shows a schematic block diagram illustrating certain exemplary features of a UE1500, e.g., which may be UE104shown inFIG.1, enabled to support positioning using an acquisition mode in which less than the full set of resources are used for PRS processing for all beams and a tracking mode in which the full set of resources are used for selected beams, as described herein. The UE1500may perform the process flow shown inFIGS.9and16and algorithms described herein. UE1500may, for example, include one or more processors1502, memory1504, an external interface such as a transceiver1510(e.g., wireless network interface), which may be operatively coupled with one or more connections1506(e.g., buses, lines, fibers, links, etc.) to non-transitory computer readable medium1520and memory1504. The UE1500may further include additional items, which are not shown, such as a user interface that may include e.g., a display, a keypad or other input device, such as virtual keypad on the display, through which a user may interface with the UE, or a satellite positioning system receiver. In certain example implementations, all or part of UE1500may take the form of a chipset, and/or the like. Transceiver1510may, for example, include a transmitter1512enabled to transmit one or more signals over one or more types of wireless communication networks and a receiver1514to receive one or more signals transmitted over the one or more types of wireless communication networks.

In some embodiments, UE1500may include antenna1511, which may be internal or external. UE antenna1511may be used to transmit and/or receive signals processed by transceiver1510. In some embodiments, UE antenna1511may be coupled to transceiver1510. The antenna1511may include more than one antenna element, and may be capable of dual polarization, MIMO-capable, beam forming, beam steering, and beam tracking. In some implementations, the antenna1511may include a plurality of panels, and each panel may include a multiple antenna array elements. In some embodiments, measurements of signals received (transmitted) by UE1500may be performed at the point of connection of the UE antenna1511and transceiver1510. For example, the measurement point of reference for received (transmitted) RF signal measurements may be an input (output) terminal of the receiver1514(transmitter1512) and an output (input) terminal of the UE antenna1511. In a UE1500with multiple UE antennas1511or antenna arrays, the antenna connector may be viewed as a virtual point representing the aggregate output (input) of multiple UE antennas. In some embodiments, UE1500may measure received signals including signal strength metrics, e.g., SNR, RSRP, RSRQ, and positioning measurements may be processed by the one or more processors1502. For example, the UE104may measure the signal strength metrics of each transmitted beam to determine the best beam(s) received by the UE104. For example, transmitted beams with signal strength metrics that are above predetermined thresholds may be treated as the best beam(s). The number of beams selected as the best beams may be based on the type of positioning measurements to be performed, e.g., time based measurements or angle based measurements.

The one or more processors1502may be implemented using a combination of hardware, firmware, and software. For example, the one or more processors1502may be configured to perform the functions discussed herein by implementing one or more instructions or program code1508on a non-transitory computer readable medium, such as medium1520and/or memory1504. In some embodiments, the one or more processors1502may represent one or more circuits configurable to perform at least a portion of a data signal computing procedure or process related to the operation of UE1500.

The medium1520and/or memory1504may store instructions or program code1508that contain executable code or software instructions that when executed by the one or more processors1502cause the one or more processors1502to operate as a special purpose computer programmed to perform the techniques disclosed herein. As illustrated in UE1500, the medium1520and/or memory1504may include one or more components or modules that may be implemented by the one or more processors1502to perform the methodologies described herein. While the components or modules are illustrated as software in medium1520that is executable by the one or more processors1502, it should be understood that the components or modules may be stored in memory1504or may be dedicated hardware either in the one or more processors1502or off the processors. A number of software modules and data tables may reside in the medium1520and/or memory1504and be utilized by the one or more processors1502in order to manage both communications and the functionality described herein. It should be appreciated that the organization of the contents of the medium1520and/or memory1504as shown in UE1500is merely exemplary, and as such the functionality of the modules and/or data structures may be combined, separated, and/or be structured in different ways depending upon the implementation of the UE1500.

The medium1520and/or memory1504may include a positioning session module1522that when implemented by the one or more processors1502configures the one or more processors1502to engage in a positioning session with a location server through a serving base station, via the wireless transceiver1510, including receiving a request for capability information and sending a response for capability information, receiving assistance data, receiving a request to provide location information, performing positioning measurements by receiving and measuring DL reference signals, transmitting UL references signals, estimating a position, sending a provide location information response, which may include positioning measurements and/or a position estimate.

The medium1520and/or memory1504may include a resource module1524that when implemented by the one or more processors1502configures the one or more processors1502to select resources to be used for receiving and processing PRS. For example, during acquisition mode, the one or more processors1502may be configured to initialize the set of resources that will be used for processing the PRS for each beam based on a fraction of the full set of resources available. For example, the one or more processors1502may be configured to tune the receiver1514to receive a fraction of the full bandwidth of the PRS while in acquisition mode, and to tune the receiver1514to the full bandwidth of the PRS while in tracking mode. In another example, during acquisition mode, the one or more processors1502may be configured to initialize the set of resources that will be used for processing the PRS for each beam based on a fraction or reduced number of repetitions of the PRS. For example, the one or more processors1502may be configured to receive and integrate over less than the full number of repetitions of the PRS while in acquisition mode, and to receive and integrate over the full number of repetitions of the PRS while in tracking mode. The one or more processors1502may be configured to increase or decrease the fraction of the full set of resources used to process PRS in subsequent positioning occasions, e.g., if less than or more than a predetermined number of beams have signal strength metrics that meet a requisite threshold. During tracking mode, the one or more processors1502may be configured to use the full set of resources for the PRS for selected beams.

The medium1520and/or memory1504may include a signal strength module1526that when implemented by the one or more processors1502configures the one or more processors1502to determine a signal strength metric for the PRS received in each beam, e.g., during acquisition mode or tracking mode. The signal strength metrics, for example, may be SNR, RSRP, RSRQ, or other types of measurements. While in acquisition mode, the one or more processors1502may be configured to compare the signal strength metrics to predetermined thresholds to determine if the PRS received from each beam exceeds the threshold. In tracking mode, the one or more processors1502may be configured to compare the signal strength metrics to signal strength metrics generated in one or more previous positioning occasions, e.g., the immediately preceding positioning occasion, the first positioning occasion of the tracking mode, or an average or combination of signal strength metrics from a plurality of proceeding positioning occasions.

The medium1520and/or memory1504may include a beam selection module1528that when implemented by the one or more processors1502configures the one or more processors1502to select a predetermined number of best beams for PRS based on the comparison of the signal strength metrics to the corresponding thresholds during the acquisition mode. The predetermined number of beams may be based on the type of positioning measurement being performed, e.g., timing based, which may use multiple beams, or angle based, which may use a single beam. The one or more processors1502may be configured to determined when fewer or a greater number than the predetermined number of beams may be selected, which may prompt an increase or decrease in the resources used to process the PRS. The one or more processors1502may be further configured to determine when the selection of beams from a previous acquisition mode may no longer be valid, e.g., after operating in tracking mode for a predetermined number of positioning occasions or when the difference between the signal strength metrics between positioning occasions in the tracking mode is greater than a threshold, and prompting a return to the acquisition mode.

The medium1520and/or memory1504may include a tracking module1530that when implemented by the one or more processors1502configures the one or more processors1502to operate in tracking mode in which PRS from a selected number of beams are processed using the full resources for the PRS and positioning measurements are performed.

The methodologies described herein may be implemented by various means depending upon the application. For example, these methodologies may be implemented in hardware, firmware, software, or any combination thereof. For a hardware implementation, the one or more processors1502may be implemented within one or more application specific integrated circuits (ASICs), digital signal processors (DSPs), digital signal processing devices (DSPDs), programmable logic devices (PLDs), field programmable gate arrays (FPGAs), processors, controllers, micro-controllers, microprocessors, electronic devices, other electronic units designed to perform the functions described herein, or a combination thereof.

For a firmware and/or software implementation, the methodologies may be implemented with modules (e.g., procedures, functions, and so on) that perform the functions described herein. Any machine readable medium tangibly embodying instructions may be used in implementing the methodologies described herein. For example, software codes may be stored in a non-transitory computer readable medium1520or memory1504that is connected to and executed by the one or more processors1502. Memory may be implemented within the one or more processors or external to the one or more processors. As used herein the term “memory” refers to any type of long term, short term, volatile, nonvolatile, or other memory and is not to be limited to any particular type of memory or number of memories, or type of media upon which memory is stored.

If implemented in firmware and/or software, the functions may be stored as one or more instructions or program code1508on a non-transitory computer readable medium, such as medium1520and/or memory1504. Examples include computer readable media encoded with a data structure and computer readable media encoded with a computer program1508. For example, the non-transitory computer readable medium including program code1508stored thereon may include program code1508to support positioning using array gain distribution variation as a function of angle and frequency in a manner consistent with disclosed embodiments. Non-transitory computer readable medium1520includes physical computer storage media. A storage medium may be any available medium that can be accessed by a computer. By way of example, and not limitation, such non-transitory computer readable media can comprise RAM, ROM, EEPROM, CD-ROM or other optical disk storage, magnetic disk storage or other magnetic storage devices, or any other medium that can be used to store desired program code1508in the form of instructions or data structures and that can be accessed by a computer; disk and disc, as used herein, includes compact disc (CD), laser disc, optical disc, digital versatile disc (DVD), floppy disk and Blu-ray disc where disks usually reproduce data magnetically, while discs reproduce data optically with lasers. Combinations of the above should also be included within the scope of computer readable media.

In addition to storage on computer readable medium1520, instructions and/or data may be provided as signals on transmission media included in a communication apparatus. For example, a communication apparatus may include a transceiver1510having signals indicative of instructions and data. The instructions and data are configured to cause one or more processors to implement the functions outlined in the claims. That is, the communication apparatus includes transmission media with signals indicative of information to perform disclosed functions.

Memory1504may represent any data storage mechanism. Memory1504may include, for example, a primary memory and/or a secondary memory. Primary memory may include, for example, a random access memory, read only memory, etc. While illustrated in this example as being separate from one or more processors1502, it should be understood that all or part of a primary memory may be provided within or otherwise co-located/coupled with the one or more processors1502. Secondary memory may include, for example, the same or similar type of memory as primary memory and/or one or more data storage devices or systems, such as, for example, a disk drive, an optical disc drive, a tape drive, a solid state memory drive, etc.

In certain implementations, secondary memory may be operatively receptive of, or otherwise configurable to couple to a non-transitory computer readable medium1520. As such, in certain example implementations, the methods and/or apparatuses presented herein may take the form in whole or part of a computer readable medium1520that may include computer implementable code1508stored thereon, which if executed by one or more processors1502may be operatively enabled to perform all or portions of the example operations as described herein. Computer readable medium1520may be a part of memory1504.

FIG.16shows a flowchart for an exemplary method1600for supporting positioning of a mobile device in a wireless network performed by the mobile device, such as UE104, in a manner consistent with disclosed implementation.

At block1602, the mobile device receives positioning reference signals (PRS) transmitted in a plurality of beams from a base station using less than a full set of resources for the PRS produced by each beam, wherein less than the full set of resources for the PRS comprises less than a full bandwidth, less than a full number of repetitions in a positioning occasion, or a combination thereof, e.g., as discussed at blocks904and906ofFIG.9andFIGS.11A,11B,12, and13. A means for receiving positioning reference signals (PRS) transmitted in a plurality of beams from a base station using less than a full set of resources for the PRS produced by each beam, wherein less than the full set of resources for the PRS comprises less than a full bandwidth, less than a full number of repetitions in a positioning occasion, or a combination thereof may include, e.g., the wireless transceiver1510and one or more processors1502with dedicated hardware or implementing executable code or software instructions in memory1504and/or medium1520such as the positioning session module1522, and the resource module1524in UE1500shown inFIG.15.

At block1604, the mobile device selects a predetermined number of beams from the plurality of beams, e.g., as discussed at blocks906and908ofFIG.9andFIGS.11A,11B,12, and13. A means for selecting a predetermined number of beams from the plurality of beams may include, e.g., the one or more processors1502with dedicated hardware or implementing executable code or software instructions in memory1504and/or medium1520such as the signal strength module1526, and the beam selection module1528in UE1500shown inFIG.15.

At block1606, the mobile device receives the PRS from the selected beams using the full set of resources for the PRS produced by each selected beam, e.g., as discussed at blocks920and922ofFIG.9andFIGS.11A,11B,12, and13. A means for receiving the PRS from the selected beams using the full set of resources for the PRS produced by each selected beam may include, e.g., the wireless transceiver1510and one or more processors1502with dedicated hardware or implementing executable code or software instructions in memory1504and/or medium1520such as the positioning session module1522, the resource module1524, and the receiving module1530in UE1500shown inFIG.15.

In one implementation, the mobile device may perform positioning of the mobile device using the received PRS from the selected beams, e.g., as discussed at block922ofFIG.9andFIGS.11A,11B,12, and13. A means for performing positioning of the mobile device using the received PRS from the selected beams may include, e.g., the wireless transceiver1510and one or more processors1502with dedicated hardware or implementing executable code or software instructions in memory1504and/or medium1520such as the positioning session module1522and the receiving module1530in UE1500shown inFIG.15.

In one implementation, the mobile device may receive the PRS using less than the full set of resources for the PRS produced by each beam by selecting a fraction of the full bandwidth and tuning to receive radio signals on the fraction of the full bandwidth, and may receive the PRS from the selected beams using the full set of resources for the PRS produced by each selected beam by tuning to receive radio signals on the full bandwidth, e.g., as discussed at blocks904and906ofFIG.9.

In one implementation, the mobile device may receive the PRS using less than the full set of resources for the PRS produced by each beam by selecting a fraction of the full number of repetitions for the PRS and integrating over only the fraction of the full number of repetitions to receive the PRS, and may receive the PRS from the selected beams using the full set of resources for the PRS produced by each selected beam by integrating over the full number of repetitions to receive the PRS, e.g., as discussed at blocks904and906ofFIG.9.

In one implementation, the mobile device may select the predetermined number of beams by determining at least one signal strength metric for each beam in the plurality of beams, e.g., as discussed at block906ofFIG.9. The mobile device may compare the at least one signal strength metric to a corresponding at least one predetermined threshold, e.g., as discussed at block908ofFIG.9. The mobile device may select the predetermined number of beams based on the comparison of the at least one signal strength metric to the corresponding at least one predetermined threshold, e.g., as discussed at blocks908and910ofFIG.9. For example, the at least one signal strength metric comprises Signal to Noise Ratio (SNR), Reference Signal Received Power (RSRP), or Reference Signal Received Quality (RSRQ). A means for selecting the predetermined number of beams by determining at least one signal strength metric for each beam in the plurality of beams, a means for comparing the at least one signal strength metric to a corresponding at least one predetermined threshold, and a means for selecting the predetermined number of beams based on the comparison of the at least one signal strength metric to the corresponding at least one predetermined threshold may include, e.g., the one or more processors1502with dedicated hardware or implementing executable code or software instructions in memory1504and/or medium1520such as the signal strength module1526, and the beam selection module1528in UE1500shown inFIG.15.

In one implementation, the mobile device may select the predetermined number of beams based on at least one signal strength metric of each beam by selecting at least one of a fraction of the full bandwidth or a fraction of the full number of repetitions to receive the PRS, e.g., as discussed at block904ofFIG.9. The mobile device may determine whether the at least one signal strength metric exceeds a corresponding at least one predetermined threshold, e.g., as discussed at blocks906and908ofFIG.9. The mobile device may increase the at least one of the fraction of the full bandwidth or the fraction of the full number of repetitions to receive the PRS when the at least one signal strength metric does not exceed the corresponding at least one predetermined threshold for the predetermined number of beams, e.g., as discussed at block912ofFIG.9. For example, the mobile device may iteratively increase the at least one of the fraction of the full bandwidth or the fraction of the full number of repetitions to receive the PRS and determining whether the at least one signal strength metric exceeds the corresponding at least one predetermined threshold until the at least one signal strength metric exceeds the corresponding at least one predetermined threshold for the predetermined number of beams. A means for selecting at least one of a fraction of the full bandwidth or a fraction of the full number of repetitions to receive the PRS, a means for determining whether the at least one signal strength metric exceeds a corresponding at least one predetermined threshold, and a means for increasing the at least one of the fraction of the full bandwidth or the fraction of the full number of repetitions to receive the PRS when the at least one signal strength metric does not exceed the corresponding at least one predetermined threshold for the predetermined number of beams may include, e.g., the wireless transceiver1510and one or more processors1502with dedicated hardware or implementing executable code or software instructions in memory1504and/or medium1520such as the signal strength module1526, and the beam selection module1528and the resource module1524in UE1500shown inFIG.15.

In one implementation, the mobile device may select the predetermined number of beams based on at least one signal strength metric of each beam by selecting at least one of a fraction of the full bandwidth or a fraction of the full number of repetitions to receive the PRS, e.g., as discussed at block904ofFIG.9. The mobile device may determine whether the at least one signal strength metric exceeds a corresponding at least one predetermined threshold, e.g., as discussed at blocks906and908ofFIG.9. The mobile device may select the predetermined number of beams for receiving when the at least one signal strength metric exceeds the corresponding at least one predetermined threshold for more than the predetermined number of beams, e.g., as discussed at block908and910ofFIG.9. The mobile device may decrease the at least one of the fraction of the full bandwidth or the fraction of the full number of repetitions to receive the PRS in a subsequent positioning occasion. A means for selecting at least one of a fraction of the full bandwidth or a fraction of the full number of repetitions to receive the PRS, a means for determining whether the at least one signal strength metric exceeds a corresponding at least one predetermined threshold, and a means for selecting the predetermined number of beams for receiving when the at least one signal strength metric exceeds the corresponding at least one predetermined threshold for more than the predetermined number of beams may include, e.g., the wireless transceiver1510and one or more processors1502with dedicated hardware or implementing executable code or software instructions in memory1504and/or medium1520such as the signal strength module1526, and the beam selection module1528and the resource module1524in UE1500shown inFIG.15.

In one embodiment, the mobile device may receive the PRS from the selected beams using the full set of resources for the PRS produce by each selected beam for multiple positioning occasions, e.g., as discussed at blocks920and922ofFIG.9andFIGS.11A,11B,12, and13. The mobile device may determine a difference in at least one signal strength metric between two positioning occasions for one or more selected beams is below a predetermined threshold, e.g., as discussed at block922ofFIG.9. The mobile device may receive the PRS transmitted in the plurality of beams using less than the full set of resources for the PRS produced by each beam after determining the difference is below the predetermined threshold, e.g., as discussed at blocks922and902ofFIG.9andFIGS.11A,11B,12, and13. A means for receiving the PRS from the selected beams using the full set of resources for the PRS produce by each selected beam for multiple positioning occasions may include, e.g., the wireless transceiver1510and one or more processors1502with dedicated hardware or implementing executable code or software instructions in memory1504and/or medium1520such as the positioning session module1522, the resource module1524, and the receiving module1530in UE1500shown inFIG.15. A means for determining a difference in at least one signal strength metric between two positioning occasions for one or more selected beams is below a predetermined threshold may include, e.g., the one or more processors1502with dedicated hardware or implementing executable code or software instructions in memory1504and/or medium1520such as the positioning session module1522, the signal strength module1526, and the beam selection module1528in UE1500shown inFIG.15. A means for receiving the PRS transmitted in the plurality of beams using less than the full set of resources for the PRS produced by each beam after determining the difference is below the predetermined threshold may include, e.g., the wireless transceiver1510and one or more processors1502with dedicated hardware or implementing executable code or software instructions in memory1504and/or medium1520such as the positioning session module1522, the resource module1524, and the beam selection module1528in UE1500shown inFIG.15.

In one embodiment, the mobile device may receive the PRS from the selected beams using the full set of resources for the PRS produce by each selected beam for multiple positioning occasions, e.g., as discussed at blocks920and922ofFIG.9andFIGS.11A,11B,12, and13. The mobile device may receive the PRS transmitted in the plurality of beams using less than the full set of resources for the PRS produced by each beam after the predetermined number of positioning occasions, e.g., as discussed at blocks922and902ofFIG.9andFIGS.11A,11B,12, and13. A means for receiving the PRS from the selected beams using the full set of resources for the PRS produce by each selected beam for a predetermined number of positioning occasions may include, e.g., the wireless transceiver1510and one or more processors1502with dedicated hardware or implementing executable code or software instructions in memory1504and/or medium1520such as the positioning session module1522, the resource module1524, and the receiving module1530in UE1500shown inFIG.15. A means for receiving the PRS transmitted in the plurality of beams using less than the full set of resources for the PRS produced by each beam after the predetermined number of positioning occasions may include, e.g., the wireless transceiver1510and one or more processors1502with dedicated hardware or implementing executable code or software instructions in memory1504and/or medium1520such as the positioning session module1522, the resource module1524, and the beam selection module1526in UE1500shown inFIG.15.

Reference throughout this specification to “one example”, “an example”, “certain examples”, or “exemplary implementation” means that a particular feature, structure, or characteristic described in connection with the feature and/or example may be included in at least one feature and/or example of claimed subject matter. Thus, the appearances of the phrase “in one example”, “an example”, “in certain examples” or “in certain implementations” or other like phrases in various places throughout this specification are not necessarily all referring to the same feature, example, and/or limitation. Furthermore, the particular features, structures, or characteristics may be combined in one or more examples and/or features.

Some portions of the detailed description included herein are presented in terms of algorithms or symbolic representations of operations on binary digital signals stored within a memory of a specific apparatus or special purpose computing device or platform. In the context of this particular specification, the term specific apparatus or the like includes a general purpose computer once it is programmed to perform particular operations pursuant to instructions from program software. Algorithmic descriptions or symbolic representations are examples of techniques used by those of ordinary skill in the signal processing or related arts to convey the substance of their work to others skilled in the art. An algorithm is here, and generally, is considered to be a self-consistent sequence of operations or similar signal processing leading to a desired result. In this context, operations or processing involve physical manipulation of physical quantities. Typically, although not necessarily, such quantities may take the form of electrical or magnetic signals capable of being stored, transferred, combined, compared or otherwise manipulated. It has proven convenient at times, principally for reasons of common usage, to refer to such signals as bits, data, values, elements, symbols, characters, terms, numbers, numerals, or the like. It should be understood, however, that all of these or similar terms are to be associated with appropriate physical quantities and are merely convenient labels. Unless specifically stated otherwise, as apparent from the discussion herein, it is appreciated that throughout this specification discussions utilizing terms such as “processing,” “computing,” “calculating,” “determining” or the like refer to actions or processes of a specific apparatus, such as a special purpose computer, special purpose computing apparatus or a similar special purpose electronic computing device. In the context of this specification, therefore, a special purpose computer or a similar special purpose electronic computing device is capable of manipulating or transforming signals, typically represented as physical electronic or magnetic quantities within memories, registers, or other information storage devices, transmission devices, or display devices of the special purpose computer or similar special purpose electronic computing device.

In the preceding detailed description, numerous specific details have been set forth to provide a thorough understanding of claimed subject matter. However, it will be understood by those skilled in the art that claimed subject matter may be practiced without these specific details. In other instances, methods and apparatuses that would be known by one of ordinary skill have not been described in detail so as not to obscure claimed subject matter.

The terms, “and”, “or”, and “and/or” as used herein may include a variety of meanings that also are expected to depend at least in part upon the context in which such terms are used. Typically, “or” if used to associate a list, such as A, B or C, is intended to mean A, B, and C, here used in the inclusive sense, as well as A, B or C, here used in the exclusive sense. In addition, the term “one or more” as used herein may be used to describe any feature, structure, or characteristic in the singular or may be used to describe a plurality or some other combination of features, structures or characteristics. Though, it should be noted that this is merely an illustrative example and claimed subject matter is not limited to this example.

While there has been illustrated and described what are presently considered to be example features, it will be understood by those skilled in the art that various other modifications may be made, and equivalents may be substituted, without departing from claimed subject matter. Additionally, many modifications may be made to adapt a particular situation to the teachings of claimed subject matter without departing from the central concept described herein.

Implementation examples are described in the following numbered clauses:

1. A method for supporting positioning of a mobile device in a wireless network performed by the mobile device, the method comprising:

receiving positioning reference signals (PRS) transmitted in a plurality of beams from a base station using less than a full set of resources for the PRS produced by each beam, wherein less than the full set of resources for the PRS comprises less than a full bandwidth, less than a full number of repetitions in a positioning occasion, or a combination thereof;

selecting a predetermined number of beams from the plurality of beams; and

receiving the PRS from the selected beams using the full set of resources for the PRS produced by each selected beam.

2. The method of clause 1, further comprising performing positioning of the mobile device using the received PRS from the selected beams.

3. The method of either of clauses 1 or 2, wherein receiving the PRS using less than the full set of resources for the PRS produced by each beam comprises selecting a fraction of the full bandwidth and tuning to receive radio signals on the fraction of the full bandwidth, and wherein receiving the PRS from the selected beams using the full set of resources for the PRS produced by each selected beam comprises tuning to receive radio signals on the full bandwidth.

4. The method of any of clauses 1-3, wherein receiving the PRS using less than the full set of resources for the PRS produced by each beam comprises selecting a fraction of the full number of repetitions for the PRS and integrating over only the fraction of the full number of repetitions to receive the PRS, and wherein receiving the PRS from the selected beams using the full set of resources for the PRS produced by each selected beam comprises integrating over the full number of repetitions to receive the PRS.

5. The method of any of clauses 1-4, wherein selecting the predetermined number of beams comprises:

determining at least one signal strength metric for each beam in the plurality of beams;

comparing the at least one signal strength metric to a corresponding at least one predetermined threshold; and

selecting the predetermined number of beams based on the comparison of the at least one signal strength metric to the corresponding at least one predetermined threshold.

6. The method of clause 5, wherein the at least one signal strength metric comprises Signal to Noise Ratio (SNR), Reference Signal Received Power (RSRP), or Reference Signal Received Quality (RSRQ).

7. The method of any of clauses 1-6, wherein the predetermined number of beams are selected based on at least one signal strength metric of each beam, and wherein the method further comprises:

selecting at least one of a fraction of the full bandwidth or a fraction of the full number of repetitions to receive the PRS;

determining whether the at least one signal strength metric exceeds a corresponding at least one predetermined threshold; and

increasing the at least one of the fraction of the full bandwidth or the fraction of the full number of repetitions to receive the PRS when the at least one signal strength metric does not exceed the corresponding at least one predetermined threshold for the predetermined number of beams.

8. The method of clause 7, further comprising iteratively increasing the at least one of the fraction of the full bandwidth or the fraction of the full number of repetitions to receive the PRS and determining whether the at least one signal strength metric exceeds the corresponding at least one predetermined threshold until the at least one signal strength metric exceeds the corresponding at least one predetermined threshold for the predetermined number of beams.

9. The method of any of clauses 1-6, wherein the predetermined number of beams are selected based on at least one signal strength metric of each beam, and wherein the method further comprises:

selecting at least one of a fraction of the full bandwidth or a fraction of the full number of repetitions to receive the PRS;

determining whether the at least one signal strength metric exceeds a corresponding at least one predetermined threshold; and

selecting the predetermined number of beams for receiving when the at least one signal strength metric exceeds the corresponding at least one predetermined threshold for more than the predetermined number of beams.

10. The method of clause 9, the method further comprising decreasing the at least one of the fraction of the full bandwidth or the fraction of the full number of repetitions to receive the PRS in a subsequent positioning occasion.

11. The method of any of clauses 1-10, further comprising:

receiving the PRS from the selected beams using the full set of resources for the PRS produce by each selected beam for multiple positioning occasions;

determining a difference in at least one signal strength metric between two positioning occasions for one or more selected beams is below a predetermined threshold; and

receiving the PRS transmitted in the plurality of beams using less than the full set of resources for the PRS produced by each beam after determining the difference is below the predetermined threshold.

12. The method of any of clauses 1-10, further comprising:

receiving the PRS from the selected beams using the full set of resources for the PRS produce by each selected beam for a predetermined number of positioning occasions; and

receiving the PRS transmitted in the plurality of beams using less than the full set of resources for the PRS produced by each beam after the predetermined number of positioning occasions.

13. A mobile device configured for supporting positioning of the mobile device in a wireless network, comprising:

a wireless transceiver configured to wirelessly communicate in the wireless network;

at least one memory;

at least one processor coupled to the wireless transceiver and the at least one memory, wherein the at least one processor is configured to:

receive, using the wireless transceiver, positioning reference signals (PRS) transmitted in a plurality of beams from a base station using less than a full set of resources for the PRS produced by each beam, wherein less than the full set of resources for the PRS comprises less than a full bandwidth, less than a full number of repetitions in a positioning occasion, or a combination thereof;

select a predetermined number of beams from the plurality of beams; and

receive, using the wireless transceiver, the PRS from the selected beams using the full set of resources for the PRS produced by each selected beam.

14. The mobile device of clause 13, wherein the at least one processor is further configured to perform positioning of the mobile device using the received PRS from the selected beams.

15. The mobile device of any of clauses 13 or 14, wherein the at least one processor is configured to receive the PRS using less than the full set of resources for the PRS produced by each beam by being configured to select a fraction of the full bandwidth and tune the wireless transceiver to receive radio signals on the fraction of the full bandwidth, and wherein the at least one processor is configured to receive the PRS from the selected beams using the full set of resources for the PRS produced by each selected beam by being configured to tune the wireless transceiver to receive radio signals on the full bandwidth.

16. The mobile device of any of clauses 13-15, wherein the at least one processor is configured to receive the PRS using less than the full set of resources for the PRS produced by each beam by being configured to select a fraction of the full number of repetitions for the PRS and integrate over only the fraction of the full number of repetitions to receive the PRS, and wherein the at least one processor is configured to receive the PRS from the selected beams using the full set of resources for the PRS produced by each selected beam by being configured to integrate over the full number of repetitions to receive the PRS.

17. The mobile device of any of clauses 13-16, wherein the at least one processor is configured to select the predetermined number of beams by being configured to:

determine at least one signal strength metric for each beam in the plurality of beams;

compare the at least one signal strength metric to a corresponding at least one predetermined threshold; and

select the predetermined number of beams based on the comparison of the at least one signal strength metric to the corresponding at least one predetermined threshold.

18. The mobile device of clause 17, wherein the at least one signal strength metric comprises Signal to Noise Ratio (SNR), Reference Signal Received Power (RSRP), or Reference Signal Received Quality (RSRQ).

19. The mobile device of any of clauses 13-18, wherein the predetermined number of beams are selected based on at least one signal strength metric of each beam, and wherein the at least one processor is further configured to:

select at least one of a fraction of the full bandwidth or a fraction of the full number of repetitions to receive the PRS;

determine whether the at least one signal strength metric exceeds a corresponding at least one predetermined threshold; and

increase the at least one of the fraction of the full bandwidth or the fraction of the full number of repetitions to receive the PRS when the at least one signal strength metric does not exceed the corresponding at least one predetermined threshold for the predetermined number of beams.

20. The mobile device of clause 19, wherein the at least one processor is further configured to iteratively increase the at least one of the fraction of the full bandwidth or the fraction of the full number of repetitions to receive the PRS and determine whether the at least one signal strength metric exceeds the corresponding at least one predetermined threshold until the at least one signal strength metric exceeds the corresponding at least one predetermined threshold for the predetermined number of beams.

21. The mobile device of any of clauses 13-18, wherein the predetermined number of beams are selected based on at least one signal strength metric of each beam, and wherein the at least one processor is further configured to:

select at least one of a fraction of the full bandwidth or a fraction of the full number of repetitions to receive the PRS;

determine whether the at least one signal strength metric exceeds a corresponding at least one predetermined threshold; and

select the predetermined number of beams for receiving when the at least one signal strength metric exceeds the corresponding at least one predetermined threshold for more than the predetermined number of beams.

22. The mobile device of clause 21, wherein the at least one processor is further configured to decrease the at least one of the fraction of the full bandwidth or the fraction of the full number of repetitions to receive the PRS in a subsequent positioning occasion.

23. The mobile device of any of clauses 13-22, wherein the at least one processor is further configured to:

receive, using the wireless transceiver, the PRS from the selected beams using the full set of resources for the PRS produce by each selected beam for multiple positioning occasions;

determine a difference in at least one signal strength metric between two positioning occasions for one or more selected beams is below a predetermined threshold; and

receive, using the wireless transceiver, the PRS transmitted in the plurality of beams using less than the full set of resources for the PRS produced by each beam after determining the difference is below the predetermined threshold.

24. The mobile device of any of clauses 13-22, wherein the at least one processor is further configured to:

receive, using the wireless transceiver, the PRS from the selected beams using the full set of resources for the PRS produce by each selected beam for a predetermined number of positioning occasions; and

receive, using the wireless transceiver, the PRS transmitted in the plurality of beams using less than the full set of resources for the PRS produced by each beam after the predetermined number of positioning occasions.

25. A mobile device configured for supporting positioning of the mobile device in a wireless network, comprising:

means for receiving positioning reference signals (PRS) transmitted in a plurality of beams from a base station using less than a full set of resources for the PRS produced by each beam, wherein less than the full set of resources for the PRS comprises less than a full bandwidth, less than a full number of repetitions in a positioning occasion, or a combination thereof;

means for selecting a predetermined number of beams from the plurality of beams; and

means for receiving the PRS from the selected beams using the full set of resources for the PRS produced by each selected beam.

26. The mobile device of clause 25, wherein the means for receiving the PRS using less than the full set of resources for the PRS produced by each beam comprises a means for selecting a fraction of the full bandwidth and means for tuning to receive radio signals on the fraction of the full bandwidth, and wherein the means for receiving the PRS from the selected beams using the full set of resources for the PRS produced by each selected beam comprises means for tuning to receive radio signals on the full bandwidth.

27. The mobile device of either of clauses 25 or 26, wherein the means for receiving the PRS using less than the full set of resources for the PRS produced by each beam comprises means for selecting a fraction of the full number of repetitions for the PRS and means for integrating over only the fraction of the full number of repetitions to receive the PRS, and wherein the means for receiving the PRS from the selected beams using the full set of resources for the PRS produced by each selected beam comprises means for integrating over full number of repetitions to receive the PRS.

28. A non-transitory computer readable storage medium including program code stored thereon, the program code is operable to configure at least one processor in a mobile device for supporting positioning of the mobile device in a wireless network, comprising:

program code to receive positioning reference signals (PRS) transmitted in a plurality of beams from a base station using less than a full set of resources for the PRS produced by each beam, wherein less than the full set of resources for the PRS comprises less than a full bandwidth, less than a full number of repetitions in a positioning occasion, or a combination thereof;

program code to select a predetermined number of beams from the plurality of beams; and

program code to receive the PRS from the selected beams using the full set of resources for the PRS produced by each selected beam.

29. The non-transitory computer readable storage medium of clause 28, wherein the program code to receive the PRS using less than the full set of resources for the PRS produced by each beam selects a fraction of the full bandwidth and tunes a wireless transceiver to receive radio signals on the fraction of the full bandwidth, and wherein the program code to receive the PRS from the selected beams using the full set of resources for the PRS produced by each selected beam tunes the wireless transceiver to receive radio signals on the full bandwidth.

30. The non-transitory computer readable storage medium of either of clauses 28 or 29, wherein the program code to receive the PRS using less than the full set of resources for the PRS produced by each beam selects a fraction of the full number of repetitions for the PRS and integrates over only the fraction of the full number of repetitions to receive the PRS, and wherein the program code to receive the PRS from the selected beams using the full set of resources for the PRS produced by each selected beam integrates over full number of repetitions to receive the PRS.

Although the present disclosure is described in connection with specific embodiments for instructional purposes, the disclosure is not limited thereto. Various adaptations and modifications may be made to the disclosure without departing from the scope. Therefore, the spirit and scope of the appended claims should not be limited to the foregoing description.