Positioning technique using positioning reference signaling

Abstract

In some implementations, a method of wireless communication includes transmitting an indication of access to a wireless channel for a positioning reference signal (PRS) group from an initiator of the PRS group to other members of the PRS group. The method further includes broadcasting a first PRS via each antenna beam of a plurality of antenna beams. An antenna array of the initiator is configured to communicate via the plurality of antenna beams. Other aspects and features are also claimed and described.

Description

Priority claims

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application claims the benefit of U.S. patent application Ser. No. 17 / 345,183, entitled "POSITIONING TECHNIQUES USING POSITIONING REFERENCE SIGNALING," filed June 11, 2021, and U.S. provisional patent application Ser. No. 63 / 047,211, entitled "POSITIONING TECHNIQUES USING POSITIONING REFERENCE SIGNALING," filed July 1, 2020, both of which are expressly incorporated by reference in their entireties into this specification. [Technical Field]

[0002] Aspects of the present disclosure relate generally to wireless communication systems, and more particularly to positioning techniques using positioning references or other similar signaling. [Background technology]

[0003]

[0003] Wireless communication networks are widely deployed to provide various communication services such as voice, video, packet data, messaging, broadcast, etc. These wireless networks may be multiple-access networks capable of supporting multiple users by sharing available network resources. Such networks may be multiple-access networks that support communication for multiple users by sharing available network resources.

[0004] A wireless communication network may include several components. These components may include wireless communication devices such as base stations (or Node Bs) that can support communication for several user equipments (UEs). The UEs may communicate with the base stations via a downlink and an uplink. The downlink (or forward link) refers to the communication link from the base station to the UE, and the uplink (or reverse link) refers to the communication link from the UE to the base station.

[0005] A base station may transmit data and control information to a UE on the downlink or receive data and control information from a UE on the uplink. On the downlink, transmissions from a base station may encounter interference due to transmissions from neighboring base stations or other wireless radio frequency (RF) transmitters. On the uplink, transmissions from a UE may encounter interference from uplink transmissions from other UEs communicating with neighboring base stations or from other wireless RF transmitters. This interference may degrade performance on both the downlink and the uplink.

[0006]

[0006] As the demand for mobile broadband access continues to increase, the potential for interference and congested networks increases, more UEs access long-range wireless communication networks, and more short-range wireless systems are deployed within communities. Research and development continues to advance wireless technologies not only to meet the growing demand for mobile broadband access, but also to evolve and improve the user experience of mobile communications.

[0007]

[0007] One technology area gaining popularity is wireless communication network access for vehicles. For example, a UE may be incorporated into a vehicle (or a component thereof), such as a "smart car," to support vehicle functions such as autonomous driving, navigation assistance, and remote device control. To enable positioning services in a vehicle that may be in motion, the vehicle may exchange one or more wireless signals (e.g., a positioning reference signal (PRS)) with a nearby wireless device, such as a roadside unit (RSU). As wireless communication networks evolve, many wireless communication networks are configured for communication in the millimeter wave (mmWave) spectrum. Due to the differences between the mmWave spectrum and lower frequencies, traditional positioning techniques (e.g., for vehicles) may be less successful when signaling is implemented in the mmWave spectrum. Summary of the Invention

[0008] The following summarizes some aspects of the present disclosure to provide a basic understanding of the described technology. This summary is not an extensive overview of all contemplated features of the present disclosure, and is not intended to identify key or critical elements of all aspects of the present disclosure, nor to delineate the scope of any or all aspects of the present disclosure. Its sole purpose is to present some concepts of one or more aspects of the present disclosure in summary form as a prelude to the more detailed description that is presented later.

[0009] In one aspect of the present disclosure, a method of wireless communication includes transmitting an indication of access to a wireless channel for a positioning reference signal (PRS) group from an initiator of the PRS group to other members of the PRS group. The method further includes broadcasting a first PRS via each antenna beam of a plurality of antenna beams. An antenna array of the initiator is configured to communicate via the plurality of antenna beams.

[0010] In an additional aspect of the present disclosure, an apparatus configured for wireless communication is disclosed. The apparatus includes at least one processor and a memory coupled to the at least one processor. The at least one processor is configured to transmit an indication of access to a wireless channel for a positioning reference signal (PRS) group from an initiator of the PRS group to other members of the PRS group. The at least one processor is further configured to broadcast a first PRS via each antenna beam of a plurality of antenna beams. An antenna array of the initiator is configured to communicate via the plurality of antenna beams.

[0011] In an additional aspect of the present disclosure, an apparatus configured for wireless communication is disclosed. The apparatus includes means for transmitting an indication of access to a wireless channel for a positioning reference signal (PRS) group from an initiator of the PRS group to other members of the PRS group. The apparatus further includes means for broadcasting a first PRS via each antenna beam of a plurality of antenna beams. An antenna array of the initiator is configured to communicate via the plurality of antenna beams.

[0012] In an additional aspect of the present disclosure, a non-transitory computer-readable medium stores instructions that, when executed by a processor, cause the processor to perform operations. The operations include transmitting an indication of access to a wireless channel for a positioning reference signal (PRS) group from an initiator of the PRS group to other members of the PRS group. The operations further include broadcasting a first PRS via each antenna beam of a plurality of antenna beams. The antenna array of the initiator is configured to communicate via the plurality of antenna beams.

[0013] In an additional aspect of the present disclosure, a method of wireless communication includes receiving, at a responder of a positioning reference signal (PRS) group, from an initiator of the PRS group, an indication of access to a wireless channel for the PRS group. The method also includes receiving a broadcast of a first PRS from the initiator. The method includes determining whether any other members of the PRS group are scheduled for PRS broadcast before the responder. The method further includes broadcasting a second PRS via each antenna beam of the one or more antenna beams based on a determination that no other members of the PRS group are scheduled for broadcast before the responder. An antenna array of the responder is configured to communicate via the one or more antenna beams.

[0014] In an additional aspect of the present disclosure, an apparatus configured for wireless communication is disclosed. The apparatus includes at least one processor and a memory coupled to the at least one processor. The at least one processor is configured to receive, at a responder of the positioning reference signal (PRS) group, an indication of access to a wireless channel for the PRS group from an initiator of the PRS group. The at least one processor is also configured to receive a broadcast of a first PRS from the initiator. The at least one processor is configured to determine whether any other members of the PRS group are scheduled for PRS broadcast before the responder. The at least one processor is further configured to broadcast a second PRS via each antenna beam of the one or more antenna beams based on a determination that no other members of the PRS group are scheduled for broadcast before the responder. An antenna array of the responder is configured to communicate via the one or more antenna beams.

[0015] In an additional aspect of the present disclosure, an apparatus configured for wireless communication is disclosed. The apparatus includes means for receiving, at a responder of a positioning reference signal (PRS) group, an indication of access to a wireless channel for the PRS group from an initiator of the PRS group. The apparatus also includes means for receiving a broadcast of a first PRS from the initiator. The apparatus includes means for determining whether any other members of the PRS group are scheduled for PRS broadcast before the responder. The apparatus further includes means for broadcasting a second PRS via each antenna beam of the one or more antenna beams based on a determination that no other members of the PRS group are scheduled for broadcast before the responder. An antenna array of the responder is configured to communicate via the one or more antenna beams.

[0016] In an additional aspect of the present disclosure, a non-transitory computer-readable medium stores instructions that, when executed by a processor, cause the processor to perform operations. The operations include receiving, at a responder of a positioning reference signal (PRS) group, from an initiator of the PRS group, an indication of access to a wireless channel for the PRS group. The operations also include receiving a broadcast of a first PRS from the initiator. The operations include determining whether any other members of the PRS group are scheduled for PRS broadcast before the responder. The operations further include broadcasting a second PRS via each antenna beam of the one or more antenna beams based on a determination that no other members of the PRS group are scheduled for broadcast before the responder. An antenna array of the responder is configured to communicate via the one or more antenna beams.

[0017] The foregoing has outlined rather broadly the features and technical advantages of examples according to the present disclosure in order that the detailed description that follows may be better understood. Additional features and advantages are described below. The concepts and specific examples disclosed may be readily utilized as a basis for modifying or designing other structures for carrying out the same purposes of the present disclosure. Such equivalent constructions do not depart from the scope of the appended claims. The nature of the concepts disclosed herein, both their organization and method of operation, together with associated advantages, will be better understood from the following description when considered in conjunction with the accompanying figures. Each of the figures is provided for the purpose of illustration and description, and not as a definition of the limits of the claims.

[0018] While aspects and implementations are described in this application by way of example, those skilled in the art will appreciate that additional implementations and use cases may occur in many different configurations and scenarios. The innovations described herein may be implemented across many different platform types, devices, systems, shapes, sizes, and packaging configurations. For example, aspects or uses may occur via integrated chip implementations and other non-modular component-based devices (e.g., end-user devices, vehicles, communications devices, computing devices, industrial equipment, retail devices, purchasing devices, medical devices, artificial intelligence (AI)-enabled devices, etc.). Some examples may or may not be directed to a particular use case or application, but broad combination applicability of the described innovations may arise. Implementations may range across a spectrum from chip-level or modular components to non-modular, non-chip-level implementations, and even to aggregated, distributed, or original equipment manufacturer (OEM) devices or systems incorporating one or more aspects of the described innovations. In some practical settings, devices incorporating the described aspects and features may also necessarily include additional components and features for implementing and practicing the claimed and described aspects. For example, transmitting and receiving wireless signals necessarily includes several components for analog and digital purposes (e.g., hardware components including antennas, radio frequency (RF) chains, power amplifiers, modulators, buffers, processors, interleavers, adders, summers, etc.). It is intended that the innovations described herein may be practiced in a wide variety of devices, chip-level components, systems, distributed configurations, end-user devices, etc., of various sizes, shapes, and configurations.

[0019] A further understanding of the nature and advantages of the present disclosure may be realized with reference to the following drawings. In the accompanying figures, similar components or features may have the same reference label. Furthermore, various components of the same type may be distinguished by following the reference label with a dash and a second label that distinguishes among those similar components. When only a first reference label is used herein, the description is applicable to any of the similar components having the same first reference label, regardless of the second reference label. [Brief explanation of the drawings]

[0020] [Figure 1]

[0020] FIG. 1 is a block diagram illustrating details of an example wireless communication system according to some aspects of the present disclosure. [Figure 2]

[0021] FIG. 1 is a block diagram conceptually illustrating an example design of a base station and a UE configured in accordance with certain aspects of the present disclosure. [Figure 3]

[0022] 1A-1C are multiple diagrams illustrating a first example of determining a vehicle's position using a positioning reference signal (PRS) method, in accordance with some aspects of the present disclosure. [Figure 4]

[0023] 10 is a ladder diagram illustrating a second example of determining a vehicle's position using a PRS method, according to some embodiments of the present disclosure. [Figure 5]

[0024] FIG. 1 is a block diagram illustrating an example of a system for enabling determination of a vehicle's position using a PRS communicated in the millimeter wave band, in accordance with certain aspects of the present disclosure. [Figure 6]

[0025] 1A-1C are multiple diagrams illustrating examples of broadcasting PRS via different antenna beams in accordance with certain aspects of the present disclosure. [Figure 7]

[0026] 1 is a flowchart of an example method for continuously broadcasting a PRS via multiple antenna beams of a roadside unit (RSU), according to certain aspects of the present disclosure. [Figure 8]

[0027] 1 is a block diagram of an example of an RSU configured to continuously broadcast a PRS via multiple antenna beams, in accordance with certain aspects of the present disclosure. [Figure 9]

[0028] 1 is a flowchart of an example method for continuously broadcasting a PRS via multiple antenna beams of a UE, in accordance with certain aspects of the present disclosure. [Figure 10]

[0029] 1 is a block diagram of an example UE configured to continuously broadcast a PRS via multiple antenna beams, in accordance with certain aspects of the present disclosure. DETAILED DESCRIPTION OF THE INVENTION

[0021]

[0030] The detailed description set forth below in connection with the accompanying drawings is intended as a description of various configurations and is not intended to limit the scope of the present disclosure. Rather, the detailed description includes specific details for the purpose of providing a thorough understanding of the subject matter of the present invention. Those skilled in the art will appreciate that these specific details are not required in every instance, and in some instances, well-known structures and components are shown in block diagram form for clarity of presentation.

[0022]

[0031] The electromagnetic spectrum is often subdivided into various classes, bands, channels, etc. based on frequency / wavelength. In fifth-generation (5G) new radio (NR), two initial operating bands are identified as frequency range designations FR1 (410 MHz to 7.125 GHz) and FR2 (24.25 GHz to 52.6 GHz). Frequencies between FR1 and FR2 are often referred to as mid-band frequencies. Although portions of FR1 are greater than 6 GHz, FR1 is often referred to (interchangeably) as the "sub-6 GHz" band in various documents and articles. A similar nomenclature issue sometimes arises regarding FR2, which is often referred to (interchangeably) as the "millimeter wave" band or spectrum in documents and articles, even though it is distinct from the extremely high frequency (EHF) band (30 GHz to 300 GHz) identified as the "millimeter wave" band by the International Telecommunications Union (ITU). With the above aspects in mind, it should be understood that unless otherwise specified, terms such as "sub-6 GHz," as used herein, may broadly refer to frequencies that may be less than 6 GHz, may be within FR1, or may include mid-band frequencies. Additionally, it should be understood that unless otherwise specified, terms such as "millimeter wave," as used herein, may broadly refer to frequencies that may include mid-band frequencies, may be within FR2, or may be within the EHF band.

[0023]

[0032] The present disclosure provides systems, apparatus, methods, and computer-readable media for supporting positioning reference signal (PRS)-based positioning using directional communication beams. For example, the present disclosure describes a PRS-based positioning process design, including group formation, listen-before-transmit (LBT) sequencing, and PRS broadcast ordering and timing, that may be implemented by devices communicating using directional communication beams (as compared to omnidirectional communication beams). The techniques of the present disclosure may support PRS-based positioning by vehicles configured for wireless communication in, for example, sub-6 GHz spectrum, millimeter wave (mmWave) spectrum (e.g., at frequencies greater than 30 gigahertz (GHz), such as between 30 and 300 GHz), or both.

[0024]

[0033] To illustrate, in an example implementation, one or more vehicles (e.g., user equipment (UE) embedded within each vehicle or component thereof) and one or more roadside units (RSUs) may form a PRS group based on geographic proximity. One member of the group may be assigned the role of initiator or may assume the role of initiator by forming a PRS group. Other group members are assigned the role of responder. As described further herein, roles within a PRS group may be assigned in various manners, such as by higher-level signaling, based on the fixed location of each device, based on the accuracy of the determined or estimated position of each device, or based on other characteristics. The initiator may perform an LBT procedure to gain access to a wireless communication channel for the PRS group and may indicate channel access to other members of the group. The responder devices may each transmit the number of antenna beams (e.g., directional antenna beams) supported at the respective responder devices, and the initiator may determine a PRS broadcast sequence and a channel occupancy time (CoT) for the PRS group. The PRS broadcast sequence may indicate the sequence (e.g., order) in which members of the PRS group are scheduled to broadcast their respective PRSs, and the CoT may be based on the total number of antenna beams supported by the PRS group. The initiator may transmit the PRS broadcast sequence, the CoT, and the number of antenna beams supported by each member of the PRS group to other members of the PRS group.

[0025]

[0034] An RSU in a PRS group may receive the indicator of channel access and other PRS group information and, based on being identified as the first in the PRS broadcast sequence, broadcast the first PRS via each antenna beam among multiple antenna beams supported by the RSU (e.g., the RSU includes an antenna array configured to communicate via multiple antenna beams). In some implementations, the RSU may sequentially broadcast the first PRS via each antenna beam among multiple antenna beams. For example, the RSU may broadcast the first PRS via the first antenna beam, followed by broadcasting (e.g., rebroadcasting) the first PRS via the second antenna beam, followed by broadcasting the first PRS via each remaining antenna beam in succession. The RSU may be configured to broadcast the first PRS via each of the antenna beams using the same sequence but different cyclic shifts so that a receiving device can identify which broadcast (or rebroadcast) of the first PRS has been received based on the cyclic shift of the received broadcast. As used herein, broadcasting may refer to the transmission of a signal or information to all wireless communication devices within a particular communication range or within a broadcast group, such as a PRS group, and transmitting may refer to the transmission of a signal or information to a particular wireless communication device or a particular number of wireless communication devices.

[0026]

[0035] Each vehicle (e.g., each UE) and any other RSUs in the PRS group may then continuously broadcast the corresponding PRS via one or more antenna beams based on the order associated with the vehicle in the PRS broadcast sequence. For example, the vehicle (e.g., UE) may receive an indication of channel availability and additional channel information from the initiator and then receive the broadcast of the first PRS from the RSU. The vehicle may wait until it determines that no other members of the PRS group are scheduled for PRS broadcast before the vehicle. For example, the vehicle may determine whether the most recently received PRS broadcast (e.g., the broadcast of the first PRS) was received from a PRS group member that immediately precedes the vehicle in the PRS broadcast sequence, and if so, determine that the PRS group member has completed PRS broadcasting based on the cyclic shift associated with the most recently received PRS broadcast and the number of antenna beams associated with the PRS group member. After such a determination, the vehicle may continuously broadcast the second PRS via one or more antenna beams supported by the vehicle's antenna array. The remaining PRS group members may similarly broadcast their respective PRSs continuously via one or more respective antenna beams. Although the RSU is described as being first in the PRS broadcast sequence in this example, in other implementations, the vehicle may be first in the PRS broadcast sequence, such as when a PRS group is formed without any RSUs.

[0027]

[0036] After completion of PRS broadcasts by all members of the PRS group, timing data may be exchanged between the RSU and the vehicle to enable estimation of the vehicle's position. In some implementations, the RSU may receive timing information from the vehicle, estimate the vehicle's position based on the timing information and timing measured at the RSU, and transmit the estimated position to the vehicle. In some other implementations, the vehicles may receive timing information from the RSU and estimate their respective relative positions based on the timing information and timing measured at the vehicle. The RSU (or vehicle) may provide timing information for each broadcast of the respective PRS so that the vehicle (or RSU) may estimate its position based on accurate timing information.

[0028]

[0037] Particular implementations of the subject matter described in this disclosure may be implemented to achieve one or more of the following potential advantages: In some aspects, the present disclosure provides techniques for supporting PRS-based positioning using directional communication beams. For example, devices may be grouped into PRS groups and may take turns continuously broadcasting their respective PRSs via one or more antenna beams supported by each device. After completion of all scheduled PRS broadcasts, the devices may exchange timing information indicating the timing of each broadcast of their respective PRSs, which may enable position estimation based on the accurate timing information. In this manner, PRS penetration or coverage issues due to beam directionality are compensated for by the techniques disclosed herein. Thus, the disclosed techniques may enable PRS-based positioning by vehicles configured to communicate in the mmWave spectrum.

[0029]

[0038] The present disclosure generally relates to providing or participating in authorized shared access between two or more wireless devices in one or more wireless communication systems, also referred to as wireless communication networks. In various implementations, the techniques and apparatus may be used for wireless communication networks such as Code Division Multiple Access (CDMA) networks, Time Division Multiple Access (TDMA) networks, Frequency Division Multiple Access (FDMA) networks, Orthogonal FDMA (OFDMA) networks, Single Carrier FDMA (SC-FDMA) networks, LTE networks, GSM networks, Fifth Generation (5G) or New Radio (NR) networks (sometimes referred to as “5G NR” networks, systems, or devices), and other communication networks. The terms “network” and “system” described herein may be used interchangeably.

[0030]

[0039] For example, a CDMA network may implement a radio technology such as Universal Terrestrial Radio Access (UTRA), cdma2000, etc. UTRA includes Wideband CDMA (W-CDMA®) and Low Chip Rate (LCR). CDMA2000 covers IS-2000, IS-95, and IS-856 standards.

[0031]

[0040] A TDMA network may implement a radio technology such as Global System for Mobile Communications (GSM). The Third Generation Partnership Project (3GPP®) is defining standards for the GSM EDGE (Enhanced Data Rates for GSM Evolution) Radio Access Network (RAN), also referred to as GERAN. GERAN, along with the network joining base stations (e.g., Ater and Abis interfaces) and base station controllers (interfaces, etc.), is the radio component of GSM / EDGE. The radio access network represents the component of a GSM network through which calls and packet data are routed between the public switched telephone network (PSTN) and the Internet and subscriber handsets, also known as user terminals or user equipment (UE). A mobile phone operator's network may comprise one or more GERANs, which in the case of a UMTS / GSM network may be coupled to a Universal Terrestrial Radio Access Network (UTRAN). Furthermore, the operator network may also include one or more LTE networks, or one or more other networks. Various different network types may use different radio access technologies (RATs) and radio access networks (RANs).

[0032]

[0041] An OFDMA network may implement radio technologies such as Evolved UTRA (E-UTRA), Institute of Electrical and Electronics Engineers (IEEE) 802.11, IEEE 802.16, IEEE 802.20, and Flash OFDM. UTRA, E-UTRA, and Global System for Mobile Communications (GSM) are parts of the Universal Mobile Telecommunications System (UMTS). In particular, Long Term Evolution (LTE) is a release of UMTS that uses E-UTRA. UTRA, E-UTRA, GSM, UMTS, and LTE are described in documents from an organization named "3rd Generation Partnership Project" (3GPP), and cdma2000 is described in documents from an organization named "3rd Generation Partnership Project 2" (3GPP2). These various radio technologies and standards are known or under development. For example, 3GPP is a collaboration among groups of telecommunications associations aimed at defining broadly applicable third-generation (3G) mobile phone specifications. 3GPP LTE is a 3GPP project aimed at improving the UMTS mobile phone standard. 3GPP may define specifications for next-generation mobile networks, mobile systems, and mobile devices. While this disclosure may describe some aspects with reference to LTE, 4G, or 5G NR technology, it will be understood that this specification is not intended to be limited to a particular technology or application, and one or more aspects described with respect to one technology may be applicable to another technology. Furthermore, one or more aspects of the present disclosure may relate to shared access to a wireless spectrum between networks using different radio access technologies or radio air interfaces.

[0033]

[0042] 5G networks contemplate diverse deployments, diverse spectrum, and diverse services and devices that can be implemented using an OFDM-based unified air interface. To achieve these goals, further enhancements to LTE and LTE-A are being considered, in addition to the development of new radio technologies for 5G NR networks. 5G NR is expected to achieve the following: (1) ultra-high density (e.g., approximately 1M nodes / km); 2 ), ultra-low complexity (e.g., about 10 bits per second), ultra-low energy (e.g., about 10+ years battery life), and deep coverage with the ability to reach difficult locations; (2) for the Internet of Things (IoT), including mission-critical control, with strong security to protect sensitive personal, financial, or confidential information, ultra-high reliability (e.g., about 99.9999% reliability), ultra-low latency (e.g., about 1 millisecond (ms)), and users with or without widespread mobility; and (3) for ultra-high capacity (e.g., about 10 Tbps / km 2 ), scaling to provide coverage with enhanced mobile broadband including extreme data rates (e.g., multi-Gbps rates, 100+ Mbps user experience rates), and deep awareness with advanced discovery and optimization.

[0034]

[0043] Devices, networks, and systems may be configured to communicate over one or more portions of the electromagnetic spectrum. The electromagnetic spectrum is often subdivided into various classes, bands, channels, etc. based on frequency or wavelength. In 5G NR, two initial operating bands have been identified as frequency range designations FR1 (410 MHz to 7.125 GHz) and FR2 (24.25 GHz to 52.6 GHz). Frequencies between FR1 and FR2 are often referred to as mid-band frequencies. Although portions of FR1 are greater than 6 GHz, FR1 is often referred to (interchangeably) as the "sub-6 GHz" band in various documents and articles. A similar nomenclature issue sometimes arises regarding FR2, which is often referred to (interchangeably) as the "millimeter wave" (mmWave) band in documents and articles, despite being distinct from the extremely high frequency (EHF) band (30 GHz to 300 GHz) identified by the International Telecommunications Union (ITU) as the "mmWave" band.

[0035]

[0044] With the above aspects in mind, it should be understood that unless otherwise specified, terms such as "sub-6 GHz," as used herein, may broadly refer to frequencies that may be less than 6 GHz, may be within FR1, or may include mid-band frequencies. Additionally, it should be understood that unless otherwise specified, terms such as "mmWave," as used herein, may broadly refer to frequencies that may include mid-band frequencies, may be within FR2, or may be within the EHF band.

[0036]

[0045] 5G NR devices, networks, and systems may be implemented using optimized OFDM-based waveform features. These features may include scalable numerology and transmission time intervals (TTIs), a common, flexible framework for efficiently multiplexing services and features in dynamic, low-latency time division duplex (TDD) or frequency division duplex (FDD) designs, and advanced wireless technologies such as massive multiple-input multiple-output (MIMO), robust mmWave transmission, advanced channel coding, and device-centric mobility. Numerology scalability in 5G NR with scaling subcarrier spacing can efficiently accommodate operating diverse services across diverse spectrum and deployments. For example, in various outdoor and macro-coverage deployments of FDD or TDD implementations below 3 GHz, subcarrier spacing with 15 kHz may occur over bandwidths of, for example, 1, 5, 10, 20 MHz, etc. In various other outdoor and small cell coverage deployments of TDD above 3 GHz, subcarrier spacing with 30 kHz may occur over 80 / 100 MHz bandwidths. In various other indoor wideband implementations using TDD in the unlicensed portion of the 5 GHz band, subcarrier spacing with 60 kHz may occur over 160 MHz bandwidths. Finally, in various deployments transmitting with mmWave components at 28 GHz TDD, subcarrier spacing with 120 kHz may occur over 500 MHz bandwidths.

[0037]

[0046] 5G NR's scalable numerology facilitates scalable TTIs for diverse latency and quality of service (QoS) requirements. For example, shorter TTIs can be used for low latency and high reliability, while longer TTIs can be used for higher spectral efficiency. Efficient multiplexing of long and short TTIs allows transmissions to start on symbol boundaries. 5G NR also contemplates a self-contained integrated subframe design with uplink or downlink scheduling information, data, and acknowledgments in the same subframe. Self-contained integrated subframes support communication in unlicensed or contention-based shared spectrum, and an adaptive uplink or downlink that can be flexibly configured per cell to dynamically switch between uplink and downlink to meet current traffic needs.

[0038]

[0047] For clarity, some aspects of the apparatus and techniques may be described below with respect to an example 5G NR implementation or in a 5G-centric manner, and 5G terminology may be used as an illustrative example in parts of the description below. However, the description is not intended to be limited to 5G applications.

[0039]

[0048] Moreover, it should be understood that, in operation, a wireless communications network adapted in accordance with the concepts herein may operate in any combination of licensed or unlicensed spectrum depending on loading and availability. Accordingly, it will be apparent to those skilled in the art that the systems, apparatus, and methods described herein may be applied to other communications systems and applications beyond the specific examples provided.

[0040]

[0049] Although aspects and implementations are described in this application by way of illustration with respect to several examples, those skilled in the art will understand that additional implementations and use cases may occur in many different configurations and scenarios. The innovations described herein may be implemented across many different platform types, devices, systems, shapes, sizes, and packaging configurations. For example, implementations or uses may occur via integrated chip implementations or other non-modular component-based devices (e.g., end-user devices, vehicles, communications devices, computing devices, industrial equipment, retail devices, purchasing devices, medical devices, AI-enabled devices, etc.). Some examples may or may not be directed to a particular use case or application, but broad combination applicability of the described innovations may arise. Implementations may range from chip-level or modular components to non-modular, non-chip-level implementations, and even to aggregated, distributed, or original equipment manufacturer (OEM) devices or systems incorporating one or more described aspects. In some practical settings, devices incorporating the described aspects and features may also include additional components and features necessary to implement and practice the claimed and described aspects. It is contemplated that the innovations described herein may be practiced in a wide variety of implementations, including both large and small devices of various sizes, shapes, and configurations, chip-level components, multi-component systems (e.g., radio frequency (RF) chains, communication interfaces, processors), distributed configurations, end-user devices, etc.

[0041]

[0050] 1 is a block diagram illustrating details of an exemplary wireless communication system. The wireless communication system may include a wireless network 100. The wireless network 100 may include, for example, a 5G wireless network. As will be appreciated by those skilled in the art, the components appearing in FIG. 1 may have related counterparts in other network configurations, including, for example, cellular-style network configurations and non-cellular-style network configurations (e.g., device-to-device or peer-to-peer or ad-hoc network configurations, etc.).

[0042]

[0051] The wireless network 100 shown in FIG. 1 includes several base stations 105 and other network entities. A base station may be a station that communicates with UEs and may also be referred to as an evolved Node B (eNB), next-generation eNB (gNB), access point, etc. Each base station 105 may provide communication coverage for a particular geographic area. In 3GPP, the term “cell” can refer to this particular geographic coverage area of the base station or base station subsystem serving the coverage area, depending on the context in which the term is used. In implementations of the wireless network 100 herein, the base stations 105 may be associated with the same operator or different operators (e.g., the wireless network 100 may include a multi-operator wireless network). Furthermore, in implementations of the wireless network 100 herein, the base station 105 may provide wireless communications using one or more of the same frequencies as neighboring cells (e.g., one or more frequency bands in a licensed spectrum, an unlicensed spectrum, or a combination thereof). In some examples, an individual base station 105 or UE 115 may be operated by more than one network operating entity. In some other examples, each base station 105 and UE 115 may be operated by a single network operating entity.

[0043]

[0052] A base station may provide communication coverage for a macro cell, or a small cell such as a pico cell or femto cell, or other type of cell. A macro cell generally covers a relatively large geographic area (e.g., a few kilometers in radius) and may allow unrestricted access by UEs that have a service subscription with the network provider. A small cell such as a pico cell generally covers a relatively smaller geographic area and may allow unrestricted access by UEs that have a service subscription with the network provider. A small cell such as a femto cell also generally covers a relatively small geographic area (e.g., a home) and may provide restricted access by UEs that have an association with the femto cell (e.g., UEs in a Closed Subscriber Group (CSG), UEs for home users, etc.) in addition to unrestricted access. A base station for a macro cell may be referred to as a macro base station. A base station for a small cell may be referred to as a small cell base station, pico base station, femto base station, or home base station. In the example shown in FIG. 1, base stations 105d and 105e are conventional macro base stations, while base stations 105a-105c are macro base stations enabled with one of three-dimensional (3D), full-dimensional (FD), or massive MIMO. Base stations 105a-105c utilize their higher-dimensional MIMO capabilities to increase coverage and capacity by leveraging 3D beamforming in both elevation and azimuth beamforming. Base station 105f is a small cell base station that may be a home node or a portable access point. A base station may support one or multiple (e.g., two, three, four, etc.) cells.

[0044]

[0053] The wireless network 100 may support synchronous or asynchronous operation. In synchronous operation, the base stations may have similar frame timing, and transmissions from different base stations may be approximately aligned in time. In asynchronous operation, the base stations may have different frame timing, and transmissions from different base stations may not be aligned in time. In some scenarios, the network may be enabled or configured to handle dynamic switching between synchronous or asynchronous operation.

[0045]

[0054] UEs 115 are dispersed throughout wireless network 100, and each UE may be stationary or mobile. While mobile devices are commonly referred to as UEs in standards and specifications promulgated by 3GPP, it should be appreciated that such devices may additionally or otherwise be referred to by those skilled in the art as mobile stations (MS), subscriber stations, mobile units, subscriber units, wireless units, remote units, mobile devices, wireless devices, wireless communication devices, remote devices, mobile subscriber stations, access terminals (ATs), mobile terminals, wireless terminals, remote terminals, handsets, terminals, user agents, mobile clients, clients, gaming devices, augmented reality devices, vehicle components, vehicle devices, or vehicle modules, or some other suitable terminology. Within this document, a "mobile" device or UE does not necessarily have the ability to move and may be stationary. For example, some non-limiting examples of mobile devices that may include one or more implementations of UE 115 include mobile, cellular (cell) phones, smartphones, session initiation protocol (SIP) phones, wireless local loop (WLL) stations, laptops, personal computers (PCs), notebooks, netbooks, smartbooks, tablets, and personal digital assistants (PDAs).Mobile devices may additionally be automobiles or other transportation vehicles, satellite radios, global positioning system (GPS) devices, global navigation satellite system (GNSS) devices, logistics controllers, drones, multicopters, quadcopters, smart energy or security devices, "Internet of Things" (IoT) or "Internet of Everything" (IoE) devices such as solar panels or solar arrays, municipal lighting, water, or other infrastructure, industrial automation and enterprise devices, consumer and wearable devices such as eyewear, wearable cameras, smart watches, health or fitness trackers, mammalian implantable devices, gesture tracking devices, medical devices, digital audio players (e.g., MP3 players), cameras, game consoles, and digital home or smart home devices such as home audio, video, and multimedia devices, appliances, sensors, vending machines, intelligent lighting, home security systems, smart meters, etc. In one aspect, a UE may be a device that includes a Universal Integrated Circuit Card (UICC). In another aspect, a UE may be a device that does not include a UICC. In some aspects, a UE that does not include a UICC may also be referred to as an IoE device. 1 are examples of mobile smartphone-type devices accessing wireless network 100. A UE may also be a machine specifically configured for connected communications, including machine-type communications (MTC), enhanced MTC (eMTC), narrowband IoT (NB-IoT), etc. UEs 115e through 115k shown in FIG. 1 are examples of various machines configured for communications accessing wireless network 100.

[0046]

[0055] A mobile device, such as the UE 115, may be capable of communicating with any type of base station, whether a macro base station, pico base station, femto base station, relay, etc. In FIG. 1, the communication links (represented as lightning bolts) indicate wireless transmissions between the UE and a serving base station, which is a base station designated to serve the UE on the downlink or uplink, or desired transmissions between base stations, and backhaul transmissions between base stations. The UE may act as a base station or other network node in some scenarios. Backhaul communication between base stations in the wireless network 100 may occur using wired or wireless communication links.

[0047]

[0056] During operation in wireless network 100, base stations 105a-105c serve UEs 115a and 115b using cooperative spatial techniques such as 3D beamforming and coordinated multipoint (CoMP) or multi-connectivity. Macro base station 105d performs backhaul communications with base stations 105a-105c, as well as small cell, base station 105f. Macro base station 105d also transmits multicast services to UEs 115c and 115d, which are subscribed to and received by them. Such multicast services may include mobile television or stream video, or other services for providing community information, such as weather emergencies or alerts, such as amber or grey alerts.

[0048]

[0057] Wireless network 100 of an implementation supports mission-critical communications with ultra-reliable and redundant links for mission-critical devices such as drone UE 115e. Redundant communication links with UE 115e include from macro base stations 105d and 105e and small cell base station 105f. Other machine-type devices such as UE 115f (thermometer), UE 115g (smart meter), and UE 115h (wearable device) may communicate through wireless network 100 directly with base stations such as small cell base station 105f and macro base station 105e, or in a multi-hop configuration by communicating with another user device that relays its information to the network, e.g., UE 115f communicating temperature measurement information to smart meter UE 115g, which is then reported to the network through small cell base station 105f. The wireless network 100 may also provide additional network efficiency through dynamic low-latency TDD or low-latency FDD communications, such as in a vehicle-to-vehicle (V2V) mesh network between the UEs 115i-115k communicating with the macro base station 105e.

[0049]

[0058] 2 shows a block diagram conceptually illustrating an exemplary design of a base station 105 and a UE 115 according to one or more aspects, which may be any of the base stations and one of the UEs of FIG. 1. In a restricted association scenario (as described above), the base station 105 may be the small cell base station 105f of FIG. 1, and the UE 115 may be a UE 115c or 115d operating in the coverage area of the base station 105f that would be included in the list of accessible UEs of the small cell base station 105f to access the small cell base station 105f. The base station 105 may also be some other type of base station. As shown in FIG. 2, the base station 105 may be equipped with antennas 234a-234t, and the UE 115 may be equipped with antennas 252a-252r to facilitate wireless communication.

[0050]

[0059] In the base station 105, the transmit processor 220 may receive data from the data source 212 and control information from a controller 240, such as a processor. The control information may be for a Physical Broadcast Channel (PBCH), a Physical Control Format Indicator Channel (PCFICH), a Physical Hybrid ARQ (Automatic Repeat Request) Indicator Channel (PHICH), a Physical Downlink Control Channel (PDCCH), an Enhanced Physical Downlink Control Channel (EPDCCH), an MTC Physical Downlink Control Channel (MPDCCH), etc. The data may be for a Physical Downlink Shared Channel (PDSCH), etc. Further, the transmit processor 220 may process (e.g., encode and symbol map) the data and control information to obtain data symbols and control symbols, respectively. The transmit processor 220 may also generate reference symbols and cell-specific reference signals, e.g., for a primary synchronization signal (PSS) and a secondary synchronization signal (SSS). The transmit (TX) multiple-input multiple-output (MIMO) processor 230 may perform spatial processing (e.g., precoding) on the data symbols, control symbols, or reference symbols, if applicable, and may provide output symbol streams to the modulators (MODs) 232a through 232t. For example, the spatial processing performed on the data symbols, control symbols, or reference symbols may include precoding. Each modulator 232 may process a respective output symbol stream (e.g., for OFDM, etc.) to obtain an output sample stream. Each modulator 232 may additionally or alternatively process (e.g., convert to analog, amplify, filter, and upconvert) the output sample stream to obtain a downlink signal. The downlink signals from the modulators 232a through 232t may be transmitted via the antennas 234a through 234t, respectively.

[0051]

[0060] At the UE 115, the antennas 252a through 252r may receive downlink signals from the base station 105 and may provide received signals to demodulators (DEMODs) 254a through 254r, respectively. Each demodulator 254 may condition (e.g., filter, amplify, downconvert, and digitize) its respective received signal to obtain input samples. Each demodulator 254 may further process the input samples (e.g., for OFDM, etc.) to obtain received symbols. A MIMO detector 256 may obtain received symbols from the demodulators 254a through 254r, perform MIMO detection on the received symbols, if applicable, and provide detected symbols. A receive processor 258 may process (e.g., demodulate, deinterleave, and decode) the detected symbols and provide decoded data for the UE 115 to a data sink 260 and decoded control information to a controller 280, such as a processor.

[0052]

[0061] On the uplink, at the UE 115, a transmit processor 264 may receive and process data from a data source 262 (e.g., on a physical uplink shared channel (PUSCH)) and may receive control information from a controller 280 (e.g., on a physical uplink control channel (PUCCH)). Additionally, the transmit processor 264 may also generate reference symbols for a reference signal. The symbols from the transmit processor 264 may be precoded by a TX MIMO processor 266 if applicable, further processed by modulators 254a through 254r (e.g., for SC-FDM, etc.), and transmitted to the base station 105. At the base station 105, uplink signals from the UE 115 may be received by antennas 234, processed by a demodulator 232, detected by a MIMO detector 236 if applicable, and further processed by a receive processor 238 to obtain decoded data and control information sent by the UE 115. The receive processor 238 may provide the decoded data to a data sink 239 and the decoded control information to a controller 240 .

[0053]

[0062] The controllers 240 and 280 may direct operation at the base station 105 and the UE 115, respectively. The controller 240 or other processors and modules at the base station 105 or the controller 280 or other processors and modules at the UE 115 may perform or direct the execution of various processes of the techniques described herein, such as for performing or directing the execution shown in FIG. 7 and FIG. 9 or other processes of the techniques described herein. The memories 242 and 282 may store data and program codes for the base station 105 and the UE 115, respectively. The scheduler 244 may schedule UEs for data transmission on the downlink or uplink.

[0054]

[0063] In some cases, the UE 115 and the base station 105 may operate in a shared radio frequency spectrum band, which may include licensed or unlicensed (e.g., contention-based) frequency spectrum. In the unlicensed frequency portion of a shared radio frequency spectrum band, the UE 115 or the base station 105 may traditionally perform a medium sensing procedure to contend for access to the frequency spectrum. For example, the UE 115 or the base station 105 may perform a listen-before-talk or listen-before-transmitting (LBT) procedure, such as clear channel assessment (CCA), before communicating to determine whether a shared channel is available. In some implementations, CCA may include an energy detection procedure to determine whether there are any other active transmissions. For example, a device may infer that a change in the received signal strength indicator (RSSI) of a power meter indicates that the channel is occupied. In particular, signal power centered in a certain bandwidth and above a predetermined noise floor may indicate another wireless transmitter. CCA may also include detection of a specific sequence that indicates channel use. For example, another device may transmit a specific preamble before transmitting a data sequence. In some cases, the LBT procedure may involve a wireless node adjusting its own backoff window based on the amount of energy detected on the channel or acknowledgement / negative acknowledgement (ACK / NACK) feedback for its own transmitted packets as a proxy for collisions.

[0055]

[0064] 3 illustrates multiple diagrams illustrating a first example of determining vehicle position using a positioning reference signal (PRS) scheme according to some aspects of the present disclosure. The example described with respect to FIG. 3 corresponds to a sidelink (SL)-based (SL-b) positioning scheme in which each vehicle estimates or calculates its position (e.g., location) in a distributed manner. The example described with respect to FIG. 4 corresponds to a sidelink-assisted (SL-a) positioning scheme in which a fixed device, such as a roadside unit (RSU) or server, estimates or calculates the vehicle's position on their behalf.

[0056]

[0065] Both types of SL positioning schemes use a round-trip time (RTT)-based approach that includes three stages. In stage 1, RSUs and vehicles are grouped. In some implementations, the grouping may be performed at a higher layer (e.g., by higher layer signaling). In stage 2, the RSUs and vehicles may perform a listen-before-transmit (LBT) procedure and broadcast their respective PRSs. In some implementations, such as when devices are communicating in an unlicensed spectrum, group LBT may be performed. For example, the initiator of the group (either an RSU or a UE) performs an LBT procedure to gain access to a wireless communication channel for the group. After the LBT procedure, the RSUs and vehicles each broadcast their respective PRSs. In stage 3, post-PRS messaging may be communicated between the RSUs and vehicles. The post-PRS message may include, for example, timing information, a measured clock error noise standard deviation, the vehicle's speed, the clock drift standard deviation, innovation measurements, location data, clock data, or a combination thereof. Either the RSU or the vehicle shares timing information, and the other device estimates or calculates the vehicle's position based on whether SL-b or SL-a positioning is performed. For example, in the SL-b positioning mode, the RSU may transmit timing information including the departure time of the RSU PRS and the arrival time of the vehicle PRS to the vehicle, and the vehicle may estimate or calculate the vehicle's position. Alternatively, in the SL-a positioning mode, the vehicle may transmit timing information including the departure time of the vehicle PRS and the arrival time of the RSU PRS to the RSU, and the RSU may estimate or calculate the vehicle's position and transmit the position data to the vehicle.

[0057]

[0066] 3 includes a ladder diagram 300 illustrating operations performed by a roadside unit (RSU) 302 and a vehicle 304 according to the SL-b positioning scheme. While an RSU 302 is described in FIG. 3, in other implementations, the RSU 302 may be replaced with a server, such as a Server Location Client Function (S-LCF).

[0058]

[0067] The RSU 302 may broadcast a first PRS (e.g., an RSU PRS) to the vehicle 304 at 306. The RSU 302 may measure a departure time t1 of the first PRS from the RSU 302, and the vehicle 304 may measure an arrival time t2 of the first PRS at the vehicle 304. Based on receiving the first PRS, the vehicle 304 may broadcast a second PRS (e.g., a vehicle PRS) to the RSU 302 at 308. The vehicle 304 may measure a departure time t3 of the second PRS from the vehicle 304, and the RSU 302 may measure an arrival time t4 of the second PRS at the RSU 302. In some implementations, the first PRS and the second PRS may be broadcast over an unlicensed spectrum. After the PRS broadcast is completed, the RSU 302 may transmit timing information to the vehicle 304 at 310. The timing information may include t1 (e.g., a departure time of the first PRS from the RSU 302) and t4 (e.g., an arrival time of the second PRS at the RSU 302). In some implementations, the timing information is communicated via vehicle-to-everything (V2X) communication or intelligent transportation system (ITS)-G5 communication, as non-limiting examples. The vehicle 304 may estimate or calculate a position, and in some implementations, a clock error, based on the timing information. For example, the vehicle 304 may estimate a position using a Kalman filter or another time-series-based technique, as non-limiting examples. In some implementations, the vehicle 304 may estimate a position based on the following equation:

[0059]

number

[0060] where zn is the round-trip time, and x(t n ) is the position at time n, and v light is the speed of light and α is a constant weighting factor.

[0061]

[0068] 3 also includes a block diagram 320 of messages communicated between each of a first RSU 322 (“RSU1”), a second RSU 324 (“RSU2”), and a third RSU 326 (“RSU3”) and a vehicle 328 according to the SL-b positioning scheme. To illustrate, the first RSU 322 may broadcast a first PRS (“1”) to the vehicle 328, the second RSU 324 may broadcast a second PRS (“2”) to the vehicle 328, and the third RSU 326 may broadcast a third PRS (“3”) to the vehicle 328. After receiving PRSs 1-3, the vehicle 328 may broadcast a fourth PRS (“4”) to each of the first RSU 322, the second RSU 324, and the third RSU 326. Each RSU may then transmit timing information including the respective t1 and t4 measurements to the vehicle 328. For example, the first RSU 322 may transmit first timing information (“6”) to the vehicle 328, the second RSU 324 may transmit second timing information (“7”) to the vehicle 328, and the third RSU 326 may transmit third timing information (“8”) to the vehicle 328. The vehicle 328 may estimate or calculate a position based on the timing information 6-8 as described above.

[0062]

[0069] 3 also includes a timing diagram 330 illustrating the timing of signals 1-8 described with respect to block diagram 320. In the SL-b positioning scheme, PRS broadcasting may be performed by each device in sequence. For example, the first RSU 322 may broadcast a first PRS (“1”), followed by the second RSU 324 broadcasting a second PRS (“2”), followed by the third RSU 326 broadcasting a third PRS (“3”), followed by the vehicle 328 broadcasting a fourth PRS (“4”). After receiving the fourth PRS, each of the RSUs 322-326 may transmit their respective timing information to the vehicle 328 in the same sequence.

[0063]

[0070] 4 is a ladder diagram 400 illustrating a second example of determining a vehicle's position using a PRS scheme, in accordance with certain aspects of the present disclosure. The example described with respect to FIG. 4 corresponds to a sidelink-assisted (SL-a) positioning scheme, in which a fixed device, such as an RSU or a server, estimates or calculates the vehicle's position on their behalf.

[0064]

[0071] The ladder diagram 400 illustrates operations performed by a roadside unit (RSU) 402 and a vehicle 404 according to the SL-a positioning method. While an RSU 402 is described in FIG. 4, in other implementations, the RSU 402 may be replaced with a server, such as an S-LCF.

[0065]

[0072] The RSU 402 may broadcast 406 a first PRS (e.g., an RSU PRS) to the vehicle 404. The RSU 402 may measure a departure time t1 of the first PRS from the RSU 402, and the vehicle 404 may measure an arrival time t2 of the first PRS at the vehicle 404. Based on receiving the first PRS, the vehicle 404 may broadcast 408 a second PRS (e.g., a vehicle PRS) to the RSU 402. The vehicle 404 may measure a departure time t3 of the second PRS from the vehicle 404, and the RSU 402 may measure an arrival time t4 of the second PRS at the RSU 402. In some implementations, the first PRS and the second PRS are broadcast over an unlicensed spectrum. After the PRS broadcast is completed, the vehicle 404 may transmit timing information to the RSU 402 at 410. The timing information may include t2 (e.g., an arrival time of the first PRS at the vehicle 404) and t3 (e.g., a departure time of the second PRS from the vehicle 404). In some implementations, the timing information is communicated via V2X or ITS-G5 communication, as non-limiting examples. The RSU 402 may estimate or calculate a position of the vehicle 404 and, in some implementations, a clock error based on the timing information and may transmit the position data (and clock data) to the vehicle 404.

[0066]

[0073] The present disclosure provides systems, apparatus, methods, and computer-readable media for supporting PRS-based positioning using directional communication beams. For example, the present disclosure describes designs for PRS-based positioning processes, including group formation, LBT sequencing, and PRS broadcast ordering and timing, that may be implemented by devices communicating using directional communication beams (as compared to omnidirectional communication beams). The techniques of the present disclosure may support PRS-based positioning by vehicles configured for wireless communication in, for example, sub-6 GHz spectrum, mmWave spectrum (e.g., at frequencies greater than 30 GHz, such as between 30 and 300 GHz), or both.

[0067]

[0074] To illustrate, in an example implementation, one or more vehicles (e.g., UEs embedded in each vehicle or component thereof) and one or more RSUs may form a PRS group based on geographic proximity. One member of the group may be assigned the role of initiator or may assume the initiator role by forming a PRS group. Other group members are assigned the role of responder. As described further herein, roles within a PRS group may be assigned in various manners, such as by higher-level signaling, based on the fixed location of each device, based on the accuracy of the determined or estimated location of each device, or based on other characteristics. The initiator may perform an LBT procedure to gain access to a wireless communication channel for the PRS group and may indicate channel access to other members of the group. The responder devices may each transmit the number of antenna beams (e.g., directional antenna beams) supported at each responder device, and the initiator may determine the PRS broadcast sequence and channel occupancy time (CoT) for the PRS group. The PRS broadcast sequence may indicate the sequence (e.g., order) in which members of the PRS group are scheduled to broadcast their respective PRSs, and the CoT may be based on the total number of antenna beams supported by the PRS group. The initiator may transmit the PRS broadcast sequence, the CoT, and the number of antenna beams supported by each member of the PRS group to other members of the PRS group.

[0068]

[0075] An RSU in a PRS group may receive the channel access and other PRS group information indicators and, based on being identified as the first in the PRS broadcast sequence, broadcast the first PRS via each antenna beam among multiple antenna beams supported by the RSU (e.g., the RSU includes an antenna array configured to communicate via multiple antenna beams). In some implementations, the RSU may sequentially broadcast the first PRS via each antenna beam among multiple antenna beams. For example, the RSU may broadcast the first PRS via the first antenna beam, followed by broadcasting (e.g., rebroadcasting) the first PRS via the second antenna beam, followed by broadcasting the first PRS via each remaining antenna beam in succession. The RSU may be configured to broadcast the first PRS via each of the antenna beams using the same sequence but different cyclic shifts so that a receiving device can identify which broadcast (or rebroadcast) of the first PRS has been received based on the cyclic shift of the received broadcast. As used herein, broadcasting may refer to the transmission of a signal or information to all wireless communication devices within a particular communication range or within a broadcast group, such as a PRS group, and transmitting may refer to the transmission of a signal or information to a particular wireless communication device or a particular number of wireless communication devices.

[0069]

[0076] Each vehicle (e.g., each UE) and any other RSUs in the PRS group may then continuously broadcast the corresponding PRS via one or more antenna beams based on the order associated with the vehicle in the PRS broadcast sequence. For example, the vehicle (e.g., UE) may receive an indication of channel availability and additional channel information from the initiator and then receive the broadcast of the first PRS from the RSU. The vehicle may wait until it determines that no other members of the PRS group are scheduled for PRS broadcast before the vehicle. For example, the vehicle may determine whether the most recently received PRS broadcast (e.g., the broadcast of the first PRS) was received from a PRS group member that immediately precedes the vehicle in the PRS broadcast sequence, and if so, determine that the PRS group member has completed PRS broadcasting based on the cyclic shift associated with the most recently received PRS broadcast and the number of antenna beams associated with the PRS group member. After such a determination, the vehicle may continuously broadcast the second PRS via one or more antenna beams supported by the vehicle's antenna array. The remaining PRS group members may similarly broadcast their respective PRSs continuously via one or more respective antenna beams. Although the RSU is described as being first in the PRS broadcast sequence in this example, in other implementations, the vehicle may be first in the PRS broadcast sequence, such as when a PRS group is formed without any RSUs.

[0070]

[0077] After completion of PRS broadcasts by all members of the PRS group, timing data may be exchanged between the RSU and the vehicle to enable estimation of the vehicle's position. In some implementations, the RSU may receive timing information from the vehicle, estimate the vehicle's position based on the timing information and timing measured at the RSU, and transmit the estimated position to the vehicle. In some other implementations, the vehicles may receive timing information from the RSU and estimate their respective relative positions based on the timing information and timing measured at the vehicle. The RSU (or vehicle) may provide timing information for each broadcast of the respective PRS so that the vehicle (or RSU) may estimate its position based on accurate timing information.

[0071]

[0078] Particular implementations of the subject matter described in this disclosure may be implemented to achieve one or more of the following potential advantages: In some aspects, the present disclosure provides techniques for supporting PRS-based positioning using directional communication beams. For example, devices may be grouped into PRS groups and may take turns continuously broadcasting their respective PRSs via one or more antenna beams supported by each device. After completion of all scheduled PRS broadcasts, the devices may exchange timing information indicating the timing of each broadcast of their respective PRSs, which may enable position estimation based on the accurate timing information. In this manner, PRS penetration or coverage issues due to beam directionality are compensated for by the techniques disclosed herein. Thus, the disclosed techniques may enable PRS-based positioning by vehicles configured to communicate in the mmWave spectrum.

[0072]

[0079] 5 is a block diagram of an example wireless communication system 500 for enabling vehicle position determination using a PRS communicated in the mmWave band in accordance with some aspects of the present disclosure. In some implementations, the wireless communication system 500 may implement aspects of the wireless network 100. The wireless communication system 500 includes a UE 115, one or more UEs 530, an initiator 540, and a roadside unit (RSU) 550. Each of the UE 115 and the UE 530 may be a vehicle (or a component thereof). The vehicle may include a car, truck, motorcycle, other type of landcraft, aircraft, watercraft, or a combination thereof. The vehicle may be at least partially operated by a user or may be autonomous or semi-autonomous, such as an unmanned aerial vehicle (UAV) (e.g., a drone), an unmanned land vehicle, or an unmanned water vehicle. Additionally or alternatively, the UE 115 and one or more UEs 530 may include or correspond to other mobile devices, such as a wearable (e.g., a watch for a pedestrian or user in a non-network-enabled vehicle, a biological monitor, a fitness device, etc.), a UE-enabled bicycle, a UE-enabled skateboard, a UE-enabled personal mobility device, etc. The RSU 550 may include or correspond to a network device having a fixed location and configured to wirelessly communicate with one or more vehicles (e.g., UEs). In some implementations, the RSU 550 may function similarly to or include a base station, such as the base station 105. Although described herein as an RSU, in some other implementations, the RSU 550 may be replaced with a server, such as an S-LCF, or other network device having a fixed location. The initiator 540 may include or correspond to an RSU or UE (e.g., a vehicle) currently acting as an initiator for a group that includes the UE 115, the UE 530, the initiator 540, and the RSU 550, as further described herein. Although two UEs and one RSU 550 are shown, in some other implementations, the wireless communication system 500 may generally include more than two UEs and may include more than two RSUs 550.

[0073]

[0080] The UE 115 may include various components (e.g., structural hardware components) used to perform one or more functions described herein. For example, these components may include a processor 502, a memory 504, an antenna array 506, a transmitter 508, and a receiver 510. The processor 502 may be configured to execute instructions stored in the memory 504 to perform the operations described herein. In some implementations, the processor 502 includes or corresponds to the controller 280, and the memory 504 includes or corresponds to the memory 282.

[0074]

[0081] The antenna array 506 (of multiple antenna panels) may include multiple antenna elements configured to conduct wireless communications with other devices, such as the UE 530, the initiator 540, and the RSU 550. In some implementations, the antenna array 506 may be configured to conduct directional wireless communications. To illustrate, each antenna element (or set of antenna elements) of the antenna array 506 may be configured to communicate using a different corresponding antenna beam having at least a different corresponding direction. For example, a first antenna element (or a first set of antenna elements) of the antenna array 506 may be configured to communicate via a first antenna beam having a first direction, a second antenna element (or a second set of antenna elements) of the antenna array 506 may be configured to communicate via a second antenna beam having a second direction, and an Nth antenna element (or an Nth set of antenna elements) of the antenna array 506 may be configured to communicate via an Nth antenna beam having an Nth direction, where N is any positive integer. The direction of the antenna beam may include or correspond to, by way of non-limiting example, the departure angle of the center of the main lobe of the antenna beam.

[0075]

[0082] The transmitter 508 is configured to transmit reference signals, control information, and data to one or more other devices, and the receiver 510 is configured to receive reference signals, synchronization signals, control information, and data from one or more other devices. For example, the transmitter 508 may transmit signaling, control information, and data, and the receiver 510 may receive signaling, control information, and data, via a network such as a wired network, a wireless network, or a combination thereof. For example, the UE 115 may be configured to transmit or receive signaling, control information, and data via a direct device-to-device connection, a local area network (LAN), a wide area network (WAN), a modem-to-modem connection, the Internet, an intranet, an extranet, a cable transmission system, a cellular communication network, any combination of the above, or any other communication network now known or later developed that enables two or more electronic devices to communicate. In some implementations, the transmitter 508 and the receiver 510 may be integrated into a transceiver. Additionally or alternatively, the transmitter 508, the receiver 510, or both may include or correspond to one or more components of the UE 115 described with reference to FIG.

[0076]

[0083] The RSU 550 may include various components (such as structural hardware components) used to perform one or more functions described herein. For example, these components may include a processor 552, a memory 554, a transmitter 556, a receiver 558, and an antenna array 559. The processor 552 may be configured to execute instructions stored in the memory 554 to perform the operations described herein. In some implementations, the processor 552 includes or corresponds to the controller 240, and the memory 554 includes or corresponds to the memory 242.

[0077]

[0084] The transmitter 556 is configured to transmit a reference signal, a synchronization signal, control information, and data to one or more other devices, and the receiver 558 is configured to receive the reference signal, the control information, and the data from one or more other devices. For example, the transmitter 556 may transmit the signaling, the control information, and the data, and the receiver 558 may receive the signaling, the control information, and the data, via a network such as a wired network, a wireless network, or a combination thereof. For example, the RSU 550 may be configured to transmit or receive data via a direct device-to-device connection, a LAN, a WAN, a modem-to-modem connection, the Internet, an intranet, an extranet, a cable transmission system, a cellular communication network, any combination of the above, or any other communication network now known or later developed that enables two or more electronic devices to communicate. In some implementations, the transmitter 556 and the receiver 558 may be integrated into a transceiver. Additionally or alternatively, the transmitter 556, the receiver 558, or both, may include or correspond to one or more components of the base station 105 described with reference to FIG.

[0078]

[0085] The antenna array 559 (or multiple antenna panels) may include multiple antenna elements configured to conduct wireless communications with other devices, such as the UE 115, the UE 530, and the initiator 540. In some implementations, the antenna array 559 may be configured to conduct directional wireless communications. To illustrate, each antenna element (or set of antenna elements) of the antenna array 559 may be configured to communicate using a different corresponding antenna beam having a different corresponding direction. For example, a first antenna element (or a first set of antenna elements) of the antenna array 559 may be configured to communicate via a first antenna beam having a first direction, a second antenna element (or a second set of antenna elements) of the antenna array 559 may be configured to communicate via a second antenna beam having a second direction, and an Mth antenna element (or an Mth set of antenna elements) of the antenna array 559 may be configured to communicate via an Mth antenna beam having an Mth direction, where M is any positive integer.

[0079]

[0086] The UEs 530 may be similar to the UEs 115. For example, each of the UEs 530 may include components similar to those described with respect to the UEs 115. The initiator 540 may be another UE or another RSU and may include components similar to those described with respect to the UEs 115 or the RSUs 550.

[0080]

[0087] In some implementations, the wireless communication system 500 implements a 5G NR network. For example, the wireless communication system 500 may include multiple 5G-capable UEs 115 and 530, such as UEs and RSUs configured to operate in accordance with a 5G NR network protocol, such as that defined by 3GPP, and multiple 5G-capable RSUs 550. In some implementations, the wireless communication system 500 is configured to support wireless communication in the mmWave spectrum.

[0081]

[0088] During operation of the wireless communication system 500, the UE 115, the UE 530, the initiator 540, and the RSU 550 may be configured into a PRS group. Devices may be included in a PRS group to enable scheduled broadcasting of PRSs over wireless communication channels, as described further herein. The PRS group may be configured at a higher layer (e.g., based on higher layer signaling). In some implementations, the PRS group may be configured based on geographic proximity. For example, the RSU 550 may have a coverage area corresponding to a portion of a road, and other devices may be included in the PRS group when they move into or are otherwise located within the portion of the road covered by the RSU 550. In some other implementations where the RSUs are not included in a PRS group, the UE 115, the UE 530, and the initiator 540 may be included in the PRS group based on their location within the coverage area of a device supporting the PRS group, such as the initiator 540, which may be a PRS anchor vehicle.

[0082]

[0089] Forming a PRS group includes assigning roles within the PRS group. For example, the initiator 540 may be assigned the role of initiator (also referred to as a group leader), and the UE 115, the UE 530, and the RSU 550 may each be assigned the role of responder. Roles within a PRS group may be assigned from a higher layer (e.g., via higher layer signaling between members of the PRS group). In some implementations, the initiator role is assigned to an RSU at a specific location. For example, the initiator role may be assigned to an RSU located approximately in the center of a portion of a road corresponding to the PRS group or to an RSU located at an intersection, as non-limiting examples. In some other implementations, the initiator role may be assigned to a particular member of a PRS group based on the particular member having a fixed location or “perfect knowledge” of the location. For example, the initiator role may be assigned to an RSU, a server, or another network device with a fixed location. Alternatively, the initiator role may be assigned to a device whose location is “perfectly known” (e.g., a device having a fixed location or a location that is determinable via external means with high precision and accuracy, such as via GPS or another positioning technique), such as an RSU (e.g., for vehicle-to-infrastructure (V2I) positioning) or a PRS anchor vehicle (e.g., for vehicle-to-vehicle (V2V) positioning). In some other implementations, the initiator role may be assigned to a particular member of a PRS group that has the largest coverage area within the PRS group. In some other implementations, the initiator role may be assigned to a particular member of a PRS group based on the particular member's determined location having the highest accuracy within the PRS group. For example, in V2V positioning, the initiator role may be assigned to the vehicle with the most accurate determined location for all members of the PRS group, such as a location determined based on an external source.In some other implementations, the initiator role may be assigned to a particular member in a PRS group based on the particular member's estimated location having the highest accuracy within the PRS group. For example, the accuracy of a location estimate may be determined or inferred based on innovation from measurements used to estimate the location. As used herein, "innovation" refers to the difference between the observed value of a variable at time t and the best prediction of that value based on information available prior to time t. In other implementations, the initiator role may be assigned based on other characteristics or parameters.

[0083]

[0090] The initiator 540 (e.g., a device assigned the initiator role for a PRS group) may be configured to organize and maintain the PRS group. In some implementations, the initiator 540 may be configured to communicate with other initiators (e.g., group leaders) of other PRS groups, e.g., to share group membership information, group membership changes, etc. To enable wireless communication for the PRS group, the initiator 540 may be configured to perform an LBT procedure on behalf of the PRS group to obtain access to a wireless communication channel. The LBT procedure may be similar to the LBT procedure performed by wireless devices communicating in lower frequency bands (e.g., at frequencies lower than those of the mmWave spectrum).

[0084]

[0091] To determine the channel occupation time (CoT) of a PRS group with respect to a wireless communication channel, the initiator 540 needs to know the total number of antenna beams (also called “sidelobes”) used by the members of the PRS group to communicate. Accordingly, each member of the PRS group may transmit to the initiator 540 the number of antenna beams supported at the respective device (e.g., the number of analog beams that may be generated or used to receive data or signaling at each member of the PRS group). For example, the RSU 550 may transmit the number of antenna beams 596 to the initiator 540, where the number of antenna beams 596 indicates the total number of antenna beams supported or otherwise used for communication by the antenna array 559 of the RSU 550. As another example, the UE 115 may transmit the number of antenna beams 598 to the initiator 540, where the number of antenna beams 598 indicates the total number of antenna beams supported or otherwise used for communication by the antenna array 506 of the UE 115. The UEs 530 may each similarly transmit the respective number of antenna beams supported at the UE to the initiator 540. In some implementations, each member of a PRS group may support the same number of antenna beams. In some other implementations, the number of antenna beams supported by at least one member of a PRS group may differ from the number of antenna beams supported by one or more other members of the PRS group.

[0085]

[0092] The initiator 540 may determine the total number of antenna beams 599 as the sum of all antenna beams supported by other members of the PRS group and the number of antenna beams supported by the initiator 540. The initiator 540 may determine a CoT for the PRS group based at least on the total number of antenna beams 599 and the PRS broadcast duration. For example, the CoT for the PRS group may be equal to the product of the total number of antenna beams 599 and the PRS broadcast duration. Alternatively, the CoT may also include additional time associated with conducting post-PRS communication, such as communication of timing information, rate information, error measurements, innovations, other information, or a combination thereof, as further described herein. In some implementations, the maximum CoT for a PRS group is less than approximately 5 ms.

[0086]

[0093] After performing the LBT procedure and gaining access to the wireless communication channel, the initiator 540 may transmit a channel access indicator 560 to the UE 115, the UE 530, and the RSU 550 (e.g., other members of the PRS group). The channel access indicator 560 may indicate access to the wireless communication channel for the PRS group, one or more parameters related to the wireless communication channel, additional information, or a combination thereof. For example, the channel access indicator 560 may identify a channel identifier associated with the wireless communication channel, a start time of access to the wireless communication channel for the PRS group, resources (e.g., time resources, frequency resources, or both) related to the access, etc. Additionally, the initiator 540 may transmit a CoT indicator 563 and a total number of antenna beams 599 to the UE 115, the UE 530, and the RSU 550. The CoT indicator 563 may indicate the duration of the CoT reserved for the PRS group with respect to the wireless communication channel. The total number of antenna beams 599 may indicate the total number of antenna beams supported by all members of the PRS group, and in some implementations may also indicate the number of antenna beams supported by each member of the PRS group. Although shown as separate transmissions in FIG. 5, in some other implementations, one or more of the channel access indicator 560, the CoT indicator 563, and the total number of antenna beams 599 may be included in the same message or transmission.

[0087]

[0094] To prevent collisions during PRS broadcast, the initiator 540 may determine a PRS broadcast sequence 561. The PRS broadcast sequence 561 may indicate a sequence (e.g., order) in which members of a PRS group are designated to broadcast corresponding PRS signals. In some implementations, RSUs (or other devices with fixed locations) are scheduled before vehicles (e.g., UEs) in the PRS broadcast sequence 561. In some other implementations, the initiator 540 may be scheduled first in the PRS broadcast sequence 561. Other orders are possible. After determining the PRS broadcast sequence 561, the initiator 540 transmits the PRS broadcast sequence 561 to the UE 115, the UE 530, and the RSUs 550 (e.g., other members of the PRS group). Although shown as a separate transmission in FIG. 5, in some other implementations, the PRS broadcast sequence 561 may be included in the same message or transmission with one or more of the channel access indicator 560, the CoT indicator 563, and the total number of antenna beams 599.

[0088]

[0095] After receiving the channel access indicator 560 and additional PRS group information (e.g., the PRS broadcast sequence 561, the CoT indicator 563, and the total number of antenna beams 599), the members of the PRS group may begin broadcasting their respective PRS signals based on the PRS broadcast sequence 561. Upon determining it is their turn (e.g., based on the PRS broadcast sequence 561), each member of the PRS group may successively broadcast their respective PRS via one or more antenna beams supported by the member of the PRS group.

[0089]

[0096] For illustration, the RSU 550 may receive the channel access indicator 560 and additional PRS group information (e.g., a PRS broadcast sequence 561, a CoT indicator 563, and a total number of antenna beams 599). Based on a determination that the RSU 550 is scheduled first in the PRS broadcast sequence 561, the RSU 550 may successively broadcast a first PRS via each antenna beam among a plurality of antenna beams supported or used for communication by the antenna array 559. An antenna beam (e.g., an analog beam), which may also be referred to as a side lobe or lobe, may correspond to a different direction in which the antenna array 559 is configured to communicate. For illustration, the RSU 550 may broadcast the first PRS one by one via each antenna beam among a plurality of antenna beams supported by the antenna array 559. Each antenna beam may be generated by a different antenna element or a subset of antenna elements of the antenna array 559. In some implementations, each antenna beam may be associated with a different direction and associated with different beamforming coefficients. In some implementations, the PRS is associated with a bandwidth of at least 40 MHz, or at least 100 MHz.

[0090]

[0097] To illustrate, the RSU 550 may broadcast a first PRS via a first antenna beam as a first PRS broadcast 562. After completing the first PRS broadcast 562, the RSU 550 may broadcast (e.g., rebroadcast) the first PRS via a second antenna beam as a first PRS broadcast 568. The first antenna beam is associated with a first direction that is different from a second direction associated with the second antenna beam (e.g., the antenna beams are generated using different antenna elements of the antenna array 559). If the antenna array 559 supports three or more antenna beams, the RSU 550 may successively broadcast the first PRS via each remaining antenna beam, similar to the first PRS broadcast 562 and the first PRS broadcast 568. Successively broadcasting a PRS via multiple antenna beams is further described with reference to FIG. 6 .

[0091]

[0098] The RSU 550 may broadcast the first PRS via each antenna beam using the same sequence. For example, in each broadcast, the first PRS may have the same pseudorandom quadrature phase shift keying (QPSK) sequence mapped in a diagonal pattern with a shift in frequency and time to avoid collisions with cell-specific reference signals and overlaps with control channels such as the physical downlink control channel (PDCCH). By way of example, the RSU 550 may use sequence 564 for the first PRS broadcast 562 and for the first PRS broadcast 568.

[0092]

[0099] To allow other members of the PRS group to determine which antenna beam is being used to broadcast the first PRS and, therefore, when the RSU 550 completes the PRS broadcasting, the RSU 550 may broadcast the first PRS via each antenna beam using a different cyclic shift. For example, the RSU 550 may delay the space-time stream by a different time reference when broadcasting the first PRS via different antenna beams. By way of illustration, the RSU 550 may apply a cyclic shift 566 to the first PRS broadcast 562 and a cyclic shift 570 to the first PRS broadcast 568. The cyclic shift 566 may differ from the cyclic shift 570 such that the cyclic shift 570 results in a longer delay than the cyclic shift 566. Because the cyclic shifts associated with each broadcast of the first PRS are different, each broadcast of the first PRS may be individually distinguishable to other members of the PRS group based at least on the cyclic shift.

[0093]

[0100] After the RSU 550 completes broadcasting the first PRS (e.g., completes each broadcast of the first PRS via each antenna beam of the multiple antenna beams supported by the antenna array 559), the other members of the PRS group may each successively broadcast their respective PRS via one or more supported antenna beams in an order indicated by the PRS broadcast sequence 561. For ease of explanation, the operations are described with respect to the UE 115. Similar operations may be performed by either the UE 530 or the initiator 540.

[0094]

[0101] The UE 115 may receive a broadcast of the first PRS from the RSU 550. For example, the UE 115 may receive the first PRS broadcast 562, the first PRS broadcast 568, or another broadcast of the first PRS from the RSU 550. After receiving the broadcast of the first PRS from the RSU 550, the UE 115 may determine whether any other members of the PRS group are scheduled for a PRS broadcast before the UE 115. Determining whether any other members of the PRS group are scheduled for a PRS broadcast before the UE 115 may include determining whether a most recently received PRS broadcast was received from a particular member of the PRS group that immediately precedes the UE 115 in the PRS broadcast sequence 561. For example, if the first PRS broadcast 562 is the most recently received PRS broadcast at the UE 115, the UE 115 may determine whether the RSU 550 immediately precedes the UE 115 in the PRS broadcast sequence 561 (e.g., whether there are no intervening members of the PRS group scheduled for a PRS broadcast). If the UE 115 determines that the RSU 550 is not immediately precedes the UE 115 in the PRS broadcast sequence 561, the UE 115 may continue to wait until receiving a broadcast of the respective PRS from a member of the PRS group that immediately precedes the UE 115 in the PRS broadcast sequence 561. For example, if the RSU 550 is first in the PRS broadcast sequence 561 and the UE 115 is third (or later) in the PRS broadcast sequence 561, the UE 115 may wait until receiving a broadcast of the respective PRS from a member of the PRS group that the UE 115 is second (or later) in the PRS broadcast sequence 561.

[0095]

[0102] If the UE 115 determines that the RSU 550 immediately precedes the UE 115 in the PRS broadcast sequence 561 (e.g., the RSU 550 is first and the UE 115 is second, or the RSU 550 and the UE 115 are adjacent at a later position in the PRS broadcast sequence 561), determining whether any other members of the PRS group are scheduled for PRS broadcast before the UE 115 may further include determining whether a particular member (e.g., a member before the UE 115 in the PRS broadcast sequence 561) has completed PRS broadcasting based on a cyclic shift associated with the most recently received PRS broadcast and the number of antenna beams associated with the particular member. For example, if the first PRS broadcast 562 is the most recently received PRS broadcast at the UE 115, the UE 115 may determine what number corresponds to the first PRS broadcast 562 in the sequence of PRS broadcasts by the RSU 550 based on a cyclic shift 566 associated with the first PRS broadcast 562. To illustrate, the UE 115 may have received the number of antenna beams associated with the RSU 550 (e.g., included in the total number of antenna beams 599 received from the initiator 540 or other PRS group information), and the UE 115 may determine the position of the first PRS broadcast 562 in the sequence of PRS broadcasts over each antenna element associated with the RSU 550 based on the cyclic shift 566. Based on this determination, the UE 115 may determine whether there are any remaining PRS broadcasts to be performed by the RSU 550.For example, if the RSU 550 is associated with four antenna beams and the UE 115 receives the first PRS broadcast 562, the UE 115 may determine, based on the cyclic shift 566 indicating that the received PRS broadcast is the first PRS broadcast performed by the RSU 550, that there are three remaining PRS broadcasts to be completed by the RSU 550 before the UE 115 can initiate the PRS broadcast. As another example, if the RSU 550 is associated with two antenna beams and the UE 115 receives the first PRS broadcast 568, the UE 115 may determine, based on the cyclic shift 570 indicating that the received PRS broadcast is the second PRS broadcast performed by the RSU 550, that there are no remaining PRS broadcasts to be completed by the RSU 550 before the UE 115 can initiate the PRS broadcast.

[0096]

[0103] Based on a determination that other members of the PRS group are not scheduled for broadcast before the UE 115, the UE 115 may successively broadcast the second PRS via each antenna beam of one or more antenna beams supported or used for communication by the antenna array 506. An antenna beam, also sometimes referred to as a sidelobe or lobe, may correspond to a different direction in which the antenna array 506 is configured to communicate. By way of example, the UE 115 may broadcast the second PRS via each antenna beam of one or more antenna beams supported by the antenna array 506. Each antenna beam may be generated by a different antenna element or a subset of antenna elements of the antenna array 506. In some implementations, each antenna beam may be associated with a different direction and associated with different beamforming coefficients. In some implementations, the antenna array 506 is configured to support multiple (e.g., two or more) antenna beams.

[0097]

[0104] To illustrate, the UE 115 may broadcast a second PRS via a first antenna beam as a second PRS broadcast 572. After completion of the second PRS broadcast 572, the UE 115 may broadcast (e.g., rebroadcast) the second PRS via a second antenna beam as a second PRS broadcast 578. The first antenna beam is associated with a first direction that is different from a second direction associated with the second antenna beam (e.g., the antenna beams are generated using different antenna elements of the antenna array 506). If the antenna array 506 supports three or more antenna beams, the UE 115 may successively broadcast the second PRS via each remaining antenna beam, similar to the second PRS broadcast 572 and the second PRS broadcast 578.

[0098]

[0105] The UE 115 may broadcast the second PRS via each antenna beam using the same sequence. For example, in each broadcast, the second PRS may have the same pseudo-random QPSK sequence mapped in a diagonal pattern with a shift in frequency and time to avoid collisions with cell-specific reference signals and overlaps with control channels such as the PDCCH. By way of example, the UE 115 may use sequence 574 for the second PRS broadcast 572 and for the second PRS broadcast 578.

[0099]

[0106] To allow other members of the PRS group to determine which antenna beam is being used to broadcast the second PRS and, therefore, when the UE 115 completes the PRS broadcasting, the UE 115 may broadcast the second PRS via each antenna beam using a different cyclic shift. For example, the UE 115 may delay the space-time stream by a different time reference when broadcasting the second PRS via different antenna beams. By way of example, the UE 115 may apply a cyclic shift 576 to the second PRS broadcast 572 and a cyclic shift 580 to the second PRS broadcast 578. The cyclic shift 576 may differ from the cyclic shift 580 such that the cyclic shift 580 results in a longer delay than the cyclic shift 576. Because the cyclic shifts associated with each broadcast of the second PRS are different, each broadcast of the second PRS may be individually distinguishable to other members of the PRS group based at least on the cyclic shift.

[0100]

[0107] After the UE 115 completes broadcasting the second first PRS (e.g., completes each broadcast of the second PRS via each antenna beam of the one or more antenna beams supported by the antenna array 506), the other members of the PRS group may each successively broadcast their respective PRS via one or more supported antenna beams in the order indicated by the PRS broadcast sequence 561. For example, each of the UEs 530 may wait until a determination that no other member of the PRS group is scheduled for a PRS broadcast before broadcasting their respective PRS as a PRS broadcast 582. If any of the UEs 530 support multiple antenna beams, broadcasting the respective PRS includes successively broadcasting the respective PRS via each antenna beam supported by the UE 530, as described with respect to the RSU 550 and the UE 115. The initiator 540 may perform similar operations to broadcast their respective PRS via one or more antenna beams supported by the initiator 540.

[0101]

[0108] After all PRS broadcasts by the PRS group are completed, the post-PRS information may be shared among the members of the PRS group. In some implementations, the post-PRS information is shared according to the SL-b method, as described with reference to Figure 3. In some other implementations, the post-PRS information is shared according to the SL-a method, as described with reference to Figure 4.

[0102]

[0109] For illustration, in an SL-b implementation, the RSU 550 may transmit timing information 584 to the UE 115. The timing information 584 may include a transmission time (e.g., a departure time) of each broadcast of the first PRS at the RSU 550, first antenna beam information indicating an antenna beam corresponding to each broadcast of the first PRS, a reception time (e.g., an arrival time) of a received broadcast of the second PRS at the RSU 550, and second antenna beam information indicating an antenna beam corresponding to the reception of the broadcast of the second PRS. For example, the timing information 584 may include a departure time (e.g., similar to the departure time t1 described with reference to FIGS. 3-4) of each broadcast of the first PRS measured by the RSU 550 and an arrival time (e.g., similar to the arrival time t4 described with reference to FIGS. 3-4) of a received broadcast of the second PRS from the UE 115 measured at the RSU 550. The first antenna beam information may indicate an identifier, a cyclic shift, or both associated with each of the departure times (e.g., to enable UE 115 to determine which departure time corresponds to the broadcast of the first PRS received at UE 115), and the second antenna beam information may indicate an identifier, a cyclic shift, or both associated with the received broadcast of the second PRS at RSU 550 (e.g., to enable UE 115 to determine which broadcast of the second PRS was received by RSU 550).

[0103]

[0110] In some implementations, the RSU 550 may transmit additional information 588 to the UE 115. For example, the RSU 550 may determine a clock error noise standard deviation, a clock drift standard deviation, or both, and the additional information 588 may include the clock error noise standard deviation, the clock drift standard deviation, or both. As another example, the RSU 550 may determine an innovation measure associated with the PRS measurements at the RSU 550, and the additional information 588 may include the innovation measure. In some implementations, the innovation measure may include or be based on the difference between an observed value of a variable at time t and a best guess of that value based on information available prior to time t.

[0104]

[0111] After receiving the timing information 584, the UE 115 may determine location data 586 indicating an estimated location of the UE 115. The location data 586 (and any other location data or estimated location data described herein) may include or indicate information that can be used to determine a location or relative location (or triangulation), such as, by way of non-limiting example, location coordinates such as latitude or longitude coordinates or Global Positioning System (GPS) coordinates, or further relative location information such as distance between each device and other devices, or, by way of non-limiting example, angle-of-arrival data. The UE 115 may determine the location data 586 based on the timing information 584, a reception time (e.g., arrival time) of the received broadcast of the first PRS from the RSU 550 measured at the UE 115 (e.g., corresponding to the arrival time t2 described with reference to FIGS. 3-4), and a transmission time (e.g., departure time) of the broadcast of the second PRS by a particular antenna beam indicated by the second antenna beam information included in the timing information 584 (e.g., corresponding to the departure time t3 described with reference to FIGS. 3-4). For example, the UE 115 may determine the location data 586 as described above with reference to FIG. 3. In some implementations, the UE 115 may also receive additional information 588 from the RSU 550, and the UE 115 may determine the location data 586 further based on the additional information 588. After determining the location data 586, the UE 115 may transmit the location data 586 to the RSU 550. In some implementations, the UE 115 may determine clock information or adjust a clock signal based on the timing information 584 and the additional information 588.

[0105]

[0112] In some implementations according to the SL-a scheme, the UE 115 may transmit timing information 590 to the RSU 550. The timing information 590 may include a reception time (e.g., an arrival time) of a received broadcast of a first PRS at the UE 115, first antenna beam information indicating an antenna beam corresponding to the received broadcast of the first PRS, a transmission time (e.g., a departure time) of each broadcast of a second PRS at the UE 115, and second antenna beam information indicating an antenna beam corresponding to each broadcast of the second PRS. For example, the timing information 590 may include an arrival time (e.g., similar to the arrival time t2 described with reference to FIGS. 3-4) of the received broadcast of the first PRS from the RSU 550 measured at the UE 115 and a departure time (e.g., similar to the departure time t3 described with reference to FIGS. 3-4) of each broadcast of the second PRS measured by the UE 115. The first antenna beam information may indicate an identifier, a cyclic shift, or both associated with a received broadcast of the first PRS at the UE 115 (e.g., to enable the RSU 550 to determine which broadcast of the first PRS was received by the UE 115), and the second antenna beam information may indicate an identifier, a cyclic shift, or both associated with each of the departure times (e.g., to enable the RSU 550 to determine which departure time corresponds to the broadcast of the second PRS received at the RSU 550).

[0106]

[0113] In some implementations, the UE 115 may transmit additional information 594 to the RSU 550. For example, the UE 115 may determine velocity information associated with the UE 115 (e.g., information indicative of one or more velocity measurements or estimates of the UE 115), and the additional information 594 may include this velocity information. Although referred to as velocity information, in other examples, the velocity information may include or be replaced with other information, such as speed information, Doppler-related information, flight information (e.g., for a UAV), etc. As another example, the UE 115 may determine a clock error noise standard deviation, a clock drift standard deviation, or both, and the additional information 594 may include the clock error noise standard deviation, the clock drift standard deviation, or both. As another example, the UE 115 may determine an innovation measurement associated with a PRS measurement at the UE 115, and the additional information 594 may include this innovation measurement.

[0107]

[0114] After receiving the timing information 590, the RSU 550 may determine location data 592 indicating an estimated location of the UE 115. The RSU 550 may determine the location data 592 based on the timing information 590, a transmission time (e.g., a departure time) of a broadcast of the first PRS by a particular antenna beam indicated by the first antenna beam information included in the timing information 590 (e.g., corresponding to the departure time t1 described with reference to FIGS. 3-4), and a reception time (e.g., an arrival time) of a received broadcast of the second PRS from the UE 115 measured at the RSU 550 (e.g., corresponding to the arrival time t4 described with reference to FIGS. 3-4). For example, the RSU 550 may determine the location data 592 as described above with reference to FIG. 3. In some implementations, the RSU 550 may also receive additional information 594 from the UE 115, and the RSU 550 may determine the location data 592 further based on the additional information 594. After determining the location data 592, the RSU 550 may transmit the location data 592 to the UE 115. In some implementations, the RSU 550 may determine clock information for the UE 115 based on the clock signal of the RSU 550, the timing information 590, the corresponding departure time t1, and the corresponding arrival time t4 (and possibly additional information 594), similar to determining the location data 592. The RSU 550 may transmit the clock information to the UE 115 for use in generating or adjusting a clock signal at the UE 115.

[0108]

[0115] As described above with respect to the RSU 550 and the UE 115, the RSU 550, the UE 530, and the initiator 540 may similarly share timing information and determine location data according to either the SL-b scheme or the SL-a scheme. Although the RSU 550 and the UE 115 have been described as being assigned the responder role in a PRS group, in other implementations, the RSU 550 or the UE 115 may be assigned the initiator role (and the initiator 540 may be absent). In such implementations, the RSU 550 or the UE 115 may perform operations to manage the PRS group, such as performing an LBT procedure and sharing a channel access indicator 560, a PRS broadcast sequence 561, a CoT indicator 563, and a total number of antenna beams 599, in addition to the operations described above with respect to the RSU 550 or the UE 115. Additionally or alternatively, although RSU 550 has been described as being scheduled first for PRS broadcasting, in other implementations, initiator 540 (or any member of a PRS group assigned the initiator role) may schedule any member of the PRS group, including initiator 540, to be first to perform PRS broadcasting.

[0109]

[0116] As described with reference to FIG. 5 , the wireless communication system 500 may support PRS-based positioning using directional communication beams. For example, each member of a PRS group may continuously broadcast its respective PRS via one or more antenna beams supported by the PRS group member. Each broadcast by a particular group member may have a different cyclic shift to enable identification of the individual broadcast by other members of the PRS group. Based on the PRS broadcast sequence 561 and the total number of antenna beams 599, each member of a PRS group may determine when all group members scheduled before it have completed their PRS broadcasts and may begin their own PRS broadcast. Furthermore, timing information shared by members of a PRS group may include antenna beam-specific timing information and information for identifying which broadcasts (e.g., corresponding to which antenna beams) have been received by other members of the PRS group. In this manner, PRS-based positioning may be supported for communications in high frequency bands, such as the mmWave spectrum.

[0110]

[0117] 6 includes multiple diagrams illustrating examples of broadcasting PRSs via different antenna beams according to some aspects of the present disclosure. For example, FIG. 6 includes a first diagram 600 of an antenna beam used to broadcast a first PRS by an initiator of a PRS group (“initiator”), a second diagram 610 of an antenna beam used to broadcast a second PRS by a first responder device of the PRS group (“responder 1”), and a third diagram 620 of an antenna beam used to broadcast a third PRS by a second responder device of the PRS group (“responder 2”). Each of initiator, responder 1, and responder 2 may include or correspond to an RSU (or other device having a fixed location, such as a server), or a vehicle (e.g., a UE incorporated in the vehicle or a component thereof). In some implementations, the initiator, responder 1, and responder 2 may include or correspond to the initiator 540 (or RSU 550 if RSU 550 is assigned the initiator role), UE 115, and UE 530, respectively, of FIG. 5.

[0111]

[0118] Each of the initiator, responder 1, and responder 2 may continuously broadcast a respective PRS via each antenna beam (e.g., a lobe or side lobe) of one or more antenna beams supported by the respective device, such as by the antenna array of the respective device. For example, the initiator may continuously broadcast a first PRS via the first antenna beam I_0, the second antenna beam I_1, the third antenna beam I_2, the fourth antenna beam I_3, the fifth antenna beam I_4, the sixth antenna beam I_5, the seventh antenna beam I_6, and the eighth antenna beam I_7. Similarly, responder 1 may continuously broadcast a second PRS via antenna beams R1_0 through R1_7, and responder 2 may continuously broadcast a third PRS via antenna beams R2_0 through R2_7. 6 as broadcasting their respective PRSs via eight antenna beams (e.g., lobes or side lobes), in other implementations, Initiator, Responder 1, and Responder 2 may each broadcast their respective PRSs via fewer than eight or more than eight antenna beams. Furthermore, while Initiator, Responder 1, and Responder 2 are shown in FIG. 6 as supporting the same number of antenna beams (e.g., eight), in other implementations, one or more of Initiator, Responder 1, and Responder 2 may support a different number of antenna beams than the others of Initiator, Responder 1, and Responder 2.

[0112]

[0119] As shown in FIG. 6, each antenna beam (e.g., lobe or side lobe) used by a device to broadcast a respective PRS may have a different direction from other antenna beams used by the same device for other PRS broadcasts. For example, the first antenna beam I_0 may have a different direction from antenna beams I_1 through I_7, the second antenna beam I_1 may have a different direction from antenna beams I_0 and I_2 through I_7, the third antenna beam I_2 may have a different direction from antenna beams I_0 through I_1 and I_3 through I_7, etc. Similarly, the antenna beams R1_0 through R1_7 may each have a different direction, and the antenna beams R2_0 through R2_7 may each have a different direction. Each of the antenna beams I_0 through I_7, R1_0 through R1_7, and R2_0 through R2_7 may be generated by a different antenna element (or a subset of antenna elements) of the antenna array of the respective device, as described with reference to FIG. 5.

[0113]

[0120] To enable differentiation or identification of which PRS broadcasts (or rebroadcasts) are received by other members of the PRS group, each PRS broadcast by a device may have a different cyclic shift than other PRS broadcasts by the same device. For example, a first PRS broadcast via a first antenna beam I_0 may have a first cyclic shift, a first PRS broadcast via a second antenna beam I_1 may have a second cyclic shift, a first PRS broadcast via a third antenna beam I_2 may have a third cyclic shift, a first PRS broadcast via a fourth antenna beam I_3 may have a fourth cyclic shift, a first PRS broadcast via a fifth antenna beam I_4 may have a fifth cyclic shift, a first PRS broadcast via a sixth antenna beam I_5 may have a sixth cyclic shift, a first PRS broadcast via a seventh antenna beam I_7 may have a seventh cyclic shift, and a first PRS broadcast via an eighth antenna beam I_7 may have an eighth cyclic shift. Similarly, each second PRS broadcast via antenna beams R1_0 through R1_7 may have a different cyclic shift, and each third PRS broadcast via antenna beams R2_0 through R2_7 may have a different cyclic shift.

[0114]

[0121] FIG. 6 also includes a timing diagram 630. The timing diagram 630 illustrates the timing of PRS broadcasts between the initiator, responder 1, and responder 2. The timing diagram 630 also illustrates a PRS group CoT, which includes the time of all PRS broadcasts within the PRS group. The PRS group CoT may indicate the duration for which access to the wireless communication channel is reserved by the initiator of the PRS group. The PRS group CoT may include an amount of time sufficient for all PRS broadcasts by all members of the PRS group. For example, the PRS group CoT may be the product of the total number of antenna beams supported by all members of the PRS group (e.g., 24 in the example of FIG. 6) and the PRS broadcast duration, which may be the same for all PRS broadcasts by all members of the PRS group. In other implementations, the PRS group CoT may include additional time for post-PRS communication, as described with reference to FIG. 5. As shown in timing diagram 630, Initiator, Responder 1, and Responder 2 each sequentially broadcast their respective PRS over all supported antenna elements in turn. The order may be indicated by a PRS group sequence determined by the initiator. While the initiator is shown as being first to perform the PRS broadcast in the example of Figure 6, in other implementations, the initiator may schedule any member of the PRS group to be first. As shown in FIG. 6, the initiator continuously broadcasts a first PRS via antenna elements I_0 to I_7 at times t_I to t_I+7T, followed by the responder 1 continuously broadcasting a second PRS via antenna elements R1_0 to R1_7 at times t_R1 to t_R1+7T, followed by the responder 2 continuously broadcasting a third PRS via antenna elements R2_0 to R2_7 at times t_R2 to t_R2+7T, where T is the PRS broadcast duration.

[0115]

[0122] A device receiving a PRS broadcast may identify the PRS broadcast based on the cyclic shift and determine whether the device can begin PRS broadcasting based on the received PRS broadcast, the PRS broadcast sequence, and the number of antenna beams associated with each other member of the PRS group. For example, if responder 1 receives a first PRS broadcast via the third antenna beam I_3, responder 1 may determine, based on the cyclic shift of the received PRS broadcast, that the received PRS broadcast is the third PRS broadcast performed by the initiator. Responder 1 may also determine, based on the initiator immediately preceding responder 1 in the PRS broadcast sequence and associated with eight antenna beams, that responder 1 should wait five additional PRS broadcast durations before beginning its own PRS broadcast. As another example, if responder 2 receives a second PRS broadcast via antenna beam R1_5, responder 2 may determine, based on the cyclic shift of the received PRS broadcast, that the received PRS broadcast is the sixth PRS broadcast conducted by responder 1. Responder 2 may also determine, based on responder 1 immediately preceding responder 2 in the PRS broadcast sequence and being associated with eight antenna beams, that responder 2 should wait two additional PRS broadcast durations before initiating its own PRS broadcast. In this manner, consecutively broadcasting PRSs using different cyclic shifts allows other members of the PRS group to determine when to initiate their respective PRS broadcasts, thereby enabling each member of the PRS group to conduct one or more consecutive PRS broadcasts without collisions during the PRS group CoT.

[0116]

[0123] FIG. 7 is a flow diagram of an example process 700 of RSU operation for continuously broadcasting PRSs via multiple antenna beams of the RSU in accordance with some aspects of the present disclosure. In some implementations, process 700 may be performed by an RSU 550 or the RSU shown in FIG. 8. In some other implementations, process 700 may be performed by an apparatus configured for wireless communication. For example, the apparatus may include at least one processor and a memory coupled to the processor. The processor may be configured to perform the operations of process 700. In some other implementations, process 700 may be implemented or executed using a non-transitory computer-readable medium having program code recorded thereon. The program code may be program code executable by a computer to cause the computer to perform the operations of process 700. In some implementations, the RSU operation is performed by an RSU assigned an initiator role for a PRS group.

[0117]

[0124] Example operations (also referred to as "blocks") of process 700 will also be described with reference to the RSU 800 shown in FIG. 8. FIG. 8 is a block diagram illustrating an example of an RSU 800 configured to continuously broadcast a PRS via multiple antenna beams, according to certain aspects of the present disclosure. The RSU 800 may include the RSU 550 of FIG. 5, as an illustrative and non-limiting example. The RSU 800 includes the structure, hardware, and components as shown for the base station 105 of FIGS. 1 and 2, the RSU 550 of FIG. 5, or a combination thereof. For example, the RSU 800 may include a controller 240 that operates to execute logic or computer instructions stored in the memory 242 and to control the components of the RSU 800 that provide the features and functionality of the RSU 800. The RSU 800 transmits and receives signals via wireless radios 801a-t and antennas 234a-t under the control of the controller 240. The wireless radios 801a-t include various components and hardware shown in FIG. 2 for the base station 105, including the modulators / demodulators 232a-t, the transmit processor 220, the TX MIMO processor 230, the MIMO detector 236, and the receive processor 238.

[0118]

[0125] As shown, the memory 242 may include a transmitting logic 802, a PRS logic 803, and a broadcasting logic 804. The transmitting logic 802 may be configured to enable transmission of information or signals, such as a PRS, to other devices. The PRS logic 803 may be configured to generate a PRS for broadcasting to other devices. The broadcasting logic 804 may be configured to initiate broadcast of information or signals, such as a PRS, to other devices. The RSU 800 may receive signals from or transmit signals to one or more UEs, such as the UE 115 of FIGS. 1-2 and 5, the UE 530 of FIG. 5, or a UE described with reference to FIG. 10, or another RSU.

[0119]

[0126] 7, the RSU 800 transmits an indication of access to a wireless channel for a PRS group from the initiator of the PRS group to other members of the PRS group, as shown in block 702. As an example of block 702, the RSU 800 may transmit the indication of wireless channel access using the wireless radios 801a-t and the antennas 252a-t and using the transmitting logic 802. For example, the RSU 800 may execute the transmitting logic 802 stored in the memory 282 under the control of the controller 280. An execution environment of the transmitting logic 802 provides functionality for transmitting an indication of access to a wireless channel for a PRS group from the initiator of the PRS group (e.g., the RSU 800) to other members of the PRS group.

[0120]

[0127] In block 704, the RSU 800 broadcasts the first PRS via each antenna beam of the multiple antenna beams. The antenna array of the RSU 800 is configured to communicate via the multiple antenna beams. For illustration, the RSU 800 may broadcast the first PRS using the wireless radios 801a-t and the antennas 252a-t (e.g., antenna arrays). For further illustration, the RSU 800 may execute the PRS logic 803 and the broadcast logic 804 stored in the memory 282 under the control of the controller 280. The execution environment of the PRS logic 803 provides functionality for generating the first PRS for broadcasting and setting parameters of each broadcast, such as a sequence and a cyclic shift, as a non-limiting example. The execution environment of the broadcast logic 804 provides functionality for broadcasting the first PRS via each antenna beam of the multiple antenna beams supported by the RSU 800.

[0121]

[0128] In some implementations, the initiator includes or corresponds to an RSU. Alternatively, the initiator may include or correspond to a UE. Additionally or alternatively, broadcasting the first PRS via each antenna beam of the multiple antenna beams may include consecutively broadcasting the first PRS via each antenna beam of the multiple antenna beams. Additionally or alternatively, process 700 may also include using the same sequence for each broadcast of the first PRS. Additionally or alternatively, process 700 may include applying a different cyclic shift to each broadcast of the first PRS. Additionally or alternatively, broadcasting the first PRS may include communicating in an mmWave band. Additionally or alternatively, each antenna beam of the multiple antenna beams may be associated with at least a partially different direction.

[0122]

[0129] In some implementations, process 700 further includes receiving a broadcast of the second PRS from a wireless communication device assigned a responder role in the PRS group. In some such implementations, the wireless communication device includes a vehicle or a component of a vehicle. Additionally or alternatively, process 700 may also include transmitting timing information to the wireless communication device after receiving a corresponding PRS broadcast from each remaining member included in the PRS group. In some such implementations, the timing information may include a transmission time of each broadcast of the first PRS, first antenna beam information indicating an antenna beam corresponding to each broadcast of the first PRS, a reception time of the broadcast of the second PRS, and second antenna beam information indicating an antenna beam corresponding to the reception of the broadcast of the second PRS. Additionally or alternatively, process 700 may further include receiving location data from the wireless communication device. The location data may be based at least in part on the timing information. In some such implementations, process 700 may also include determining a measured clock error noise standard deviation, a clock drift standard deviation, or both at the initiator and transmitting the measured clock error noise standard deviation, the clock drift standard deviation, or both at the initiator to the UE prior to receiving the location data. Additionally or alternatively, process 700 may also include determining an innovation measurement associated with the PRS measurement at the RSU and transmitting the innovation measurement to the wireless communication device prior to receiving the location data.

[0123]

[0130] In some implementations where process 700 further includes receiving a broadcast of a second PRS from a wireless communication device, process 700 may also include receiving timing information from the wireless communication device after receiving a corresponding PRS broadcast from each remaining member of the PRS group, determining location data indicating an estimated location of the UE based on the timing information, a transmission time of the broadcast of the first PRS via the antenna beam indicated by the timing information, and a reception time of the broadcast of the second PRS, and transmitting the location data to the wireless communication device. In some such implementations, process 700 may further include determining clock information for the wireless communication device based on the clock signal and the timing information of the initiator, and transmitting the clock information to the wireless communication device. Additionally or alternatively, the timing information from the wireless communication device may include a reception time of a broadcast of a first PRS at the wireless communication device, antenna beam information indicating an antenna beam corresponding to the reception of the broadcast of the first PRS at the wireless communication device, a transmission time of one or more broadcasts of a second PRS by the wireless communication device, and second antenna beam information indicating at least one antenna beam corresponding to the broadcast of the second PRS. Additionally or alternatively, process 700 may also include receiving speed information from the wireless communication device. The location data may be further based on the speed information. Additionally or alternatively, process 700 may also include receiving, from the wireless communication device, a measured clock error noise standard deviation at the wireless communication device, a clock drift standard deviation at the wireless communication device, or both. The location data may be further based on the measured clock error noise standard deviation, the clock drift standard deviation, or both. Additionally or alternatively, process 700 may also include receiving, from the wireless communication device, an innovation measurement associated with the PRS measurement at the wireless communication device. The location data may be further based on the innovation measurement.

[0124]

[0131] In some implementations, process 700 further includes transmitting a PRS broadcast sequence associated with the PRS group to other members of the PRS group. The PRS broadcast sequence may indicate a sequence in which the members of the PRS group are designated to broadcast corresponding PRS signals. Additionally or alternatively, process 700 may also include receiving, from the members of the PRS group, the number of antenna beams used by the members of the PRS group. In some such implementations, process 700 may further include transmitting, over the wireless channel, an indication of the CoT of the PRS group to the other members of the PRS group. The CoT may be based on the total number of antenna beams used by all members of the PRS group.

[0125]

[0132] In some implementations, roles within a PRS group are assigned via higher layer signaling between members of the PRS group. Additionally or alternatively, the initiator role within a PRS group may be assigned to an RSU located at a specific location. Additionally or alternatively, the initiator role within a PRS group may be assigned to a specific member of the PRS group based on the specific member having a fixed location or complete knowledge of the location. In some such implementations, the initiator includes an RSU or a PRS anchor vehicle. Additionally or alternatively, the initiator role within a PRS group may be assigned to a specific member of the PRS group that has the largest coverage area within the PRS group. Additionally or alternatively, the initiator role within a PRS group may be assigned to a specific member within the PRS group based on the specific member's determined location having the highest accuracy within the PRS group. Additionally or alternatively, the initiator role within a PRS group may be assigned to a specific member within the PRS group based on the specific member's estimated location having the highest accuracy within the PRS group.

[0126]

[0133] FIG. 9 is a flow diagram of an example process 900 of a UE operation for continuously broadcasting a PRS via multiple antenna beams of the UE in accordance with some aspects of the present disclosure. In some implementations, the process 900 may be performed by the UE 115 of FIGS. 1-2 and 5 or the UE described with reference to FIG. 10 . In some other implementations, the process 900 may be performed by an apparatus configured for wireless communication. For example, the apparatus may include at least one processor and a memory coupled to the processor. The processor may be configured to perform the operations of the process 900. In some other implementations, the process 900 may be implemented or executed using a non-transitory computer-readable medium having program code recorded thereon. The program code may be program code executable by a computer to cause the computer to perform the operations of the process 900. In some implementations, the UE operation may be performed by a UE assigned a responder role in a PRS group.

[0127]

[0134] Example blocks of process 900 will also be described with reference to UE 1000 shown in FIG. 10. FIG. 10 is a block diagram illustrating an example UE 1000 configured to continuously broadcast a PRS via multiple antenna beams, according to certain aspects of the present disclosure. While described as a UE, UE 1000 may include (or be incorporated within) a vehicle (or components thereof). UE 1000 includes the structure, hardware, and components as illustrated for UE 115 of FIGS. 1-2 or 5. For example, UE 1000 includes controller 280 that operates to execute logic or computer instructions stored in memory 282 and to control components of UE 1000 that provide the features and functionality of UE 1000. Under the control of controller 280, UE 1000 transmits and receives signals via wireless radios 1001a-r and antennas 252a-r. The wireless radios 1001a-r include various components and hardware shown in FIG. 2 for the UE 115, including the modulator / demodulators 254a-r, the MIMO detector 256, the receive processor 258, the transmit processor 264, and the TX MIMO processor 266.

[0128]

[0135] As shown, the memory 282 may include receiving logic 1002, PRS logic 1003, and broadcast logic 1004. The receiving logic 1002 may be configured to receive information or signaling from other devices, such as PRS group information or PRSs. The PRS logic 1003 may be configured to generate PRS signals for broadcasting to other devices. The broadcast logic 1004 may be configured to enable broadcast of signaling or messages to other devices, such as PRSs. The UE 1000 may receive signals from or transmit signals to one or more UEs, such as the UE 530 of FIG. 5, or one or more RSUs, such as the RSU 550 of FIG. 5 or the RSU 800 of FIG. 8.

[0129]

[0136] 9 , the UE 1000 receives an indication of access to the wireless channel for the PRS group from the initiator of the PRS group at a responder of the PRS group, as shown in block 902. For illustrative purposes, the UE 1000 may receive the indication using the wireless radios 1001a-r and antennas 252a-r and the receiving logic 1002. For further illustrative purposes, the UE 1000 may execute the receiving logic 1002 stored in the memory 282 under control of the controller 280. The execution environment of the receiving logic 1002 provides functionality for receiving an indication of access to the wireless channel for the PRS group from the initiator of the PRS group.

[0130]

[0137] At block 904, the UE 1000 receives the broadcast of the first PRS from the initiator. For illustrative purposes, the UE 1000 may receive the broadcast of the first PRS using the wireless radios 1001a-r and antennas 252a-r and the receiving logic 1002. For further illustrative purposes, the UE 1000 may execute the receiving logic 1002 stored in the memory 282 under control of the controller 280. The execution environment of the receiving logic 1002 provides functionality for receiving the broadcast of the first PRS from the initiator.

[0131]

[0138] In block 906, the UE 1000 determines whether any other members of the PRS group are scheduled for PRS broadcast before the UE 1000 (e.g., a responder). As an example of block 906, the UE 1000 may execute PRS logic 1003 stored in memory 282 under control of the controller 280. The execution environment of the PRS logic 1003 provides functionality for determining PRS broadcast scheduling, such as determining whether any other members of the PRS group are scheduled for PRS broadcast before the UE 1000.

[0132]

[0139] In block 908, the UE 1000 broadcasts the second PRS via each antenna beam of the one or more antenna beams based on determining that other members of the PRS group are not scheduled for broadcast before the UE 1000 (e.g., a responder). The antenna array of the UE 1000 is configured to communicate via the one or more antenna beams. For illustration, the UE 1000 may broadcast the second PRS using the wireless radios 1001a-r and antennas 252a-r (e.g., antenna arrays), as well as the PRS logic 1003 and the broadcast logic 1004. For further illustration, the UE 1000 may execute the PRS logic 1003 and the broadcast logic 1004 stored in the memory 282 under the control of the controller 280. The execution environment of the PRS logic 1003 provides functionality for generating the second PRS for broadcasting and setting one or more parameters related to the broadcasting, such as a sequence and a cyclic shift, as a non-limiting example. The execution environment of the broadcast logic 1004 provides functionality for broadcasting the second PRS via each antenna beam of the one or more antenna beams based on a determination that other members of the PRS group are not scheduled for broadcast before the UE 1000.

[0133]

[0140] In some implementations, the responder may include or correspond to a UE. Alternatively, the responder may include or correspond to an RSU. Additionally or alternatively, broadcasting the second PRS via each antenna beam of the one or more antenna beams may include consecutively broadcasting the second PRS via each antenna beam of the one or more antenna beams. Additionally or alternatively, process 900 may also include using the same sequence for each broadcast of the second PRS. Additionally or alternatively, process 900 may further include applying a different cyclic shift to each broadcast of the second PRS. Additionally or alternatively, broadcasting the second PRS may include communicating in an mmWave band. Additionally or alternatively, each antenna beam of the one or more antenna beams may be associated with at least a partially different direction. Additionally or alternatively, UE 1000 may include a vehicle or a component of a vehicle.

[0134]

[0141] In some implementations, the process 900 further includes receiving, from the initiator, a PRS broadcast sequence associated with the PRS group and the number of antenna beams corresponding to each member of the PRS group. The PRS broadcast sequence may indicate a sequence in which members of the PRS group are designated to broadcast corresponding PRS signals. In some such implementations, determining whether any other members of the PRS group are scheduled for PRS broadcast before the UE 1000 may include determining whether a most recently received PRS broadcast was received from a particular member of the PRS group that immediately precedes the UE 1000 in the PRS broadcast sequence. In some such implementations, determining whether any other members of the PRS group are scheduled for PRS broadcast before the UE 1000 may further include determining whether the particular member has completed PRS broadcasting based on a cyclic shift associated with the most recently received PRS broadcast and the number of antenna beams associated with the particular member.

[0135]

[0142] In some implementations, process 900 also includes receiving timing information from the initiator after receiving a corresponding PRS broadcast from each remaining member of the PRS group. In some such implementations, the timing information from the initiator may include a transmission time of each broadcast of the first PRS, first antenna beam information indicating an antenna beam of the initiator corresponding to each broadcast of the second PRS, a reception time of the broadcast of the second PRS at the initiator, and second antenna beam information indicating an antenna beam corresponding to reception of the broadcast of the second PRS at the initiator. In some such implementations, process 900 may further include determining location data indicating an estimated location of the UE 1000 based on the timing information, the reception time of the broadcast of the first PRS, and the transmission time of the broadcast of the second PRS via the antenna beam indicated by the second antenna beam information, and transmitting the location data to the initiator. Additionally or alternatively, process 900 may also include determining a measured clock error noise standard deviation at UE 1000, a clock drift standard deviation at UE 1000, or both, and transmitting the measured clock error noise standard deviation, the clock drift standard deviation, or both to the initiator. Additionally or alternatively, process 900 may also include determining an innovation measurement associated with the PRS measurement at UE 1000, and transmitting the innovation measurement to the initiator.

[0136]

[0143] In some implementations, the process 900 further includes transmitting timing information to the initiator after receiving a corresponding PRS broadcast from each remaining member of the PRS group. The timing information may indicate a reception time of the broadcast of the first PRS, antenna beam information indicating an antenna beam corresponding to the broadcast of the first PRS, a transmission time of the broadcast of the second PRS, and second antenna beam information indicating an antenna beam corresponding to the broadcast of the second PRS. In some such implementations, the process 900 may also include receiving location data from the initiator. The location data may indicate an estimated location of the UE 1000. In some such implementations, the process 900 may also include determining velocity information associated with the UE 1000 and transmitting the velocity information to the initiator prior to receiving the location data. Additionally or alternatively, process 900 may also include determining a measured clock error noise standard deviation at UE 1000, a clock drift standard deviation at UE 1000, or both, and transmitting the measured clock error noise standard deviation, the clock drift standard deviation, or both to the initiator prior to receiving the location data. Additionally or alternatively, process 900 may also include determining an innovation measurement associated with a PRS measurement at UE 1000, and transmitting the innovation measurement to the initiator prior to receiving the location data. Additionally or alternatively, process 900 may also include receiving clock information from the initiator. The clock information may indicate a clock signal to be used by UE 1000.

[0137]

[0144] In some implementations, process 900 further includes transmitting to the initiator the number of antenna beams included in the one or more antenna beams. Additionally or alternatively, process 900 may also include receiving, from the initiator, an indication of a CoT of the PRS group over the wireless channel. The CoT may be based on the total number of antenna beams used by all members of the PRS group.

[0138]

[0145] In some implementations, roles within a PRS group are assigned via higher layer signaling between members of the PRS group. Additionally or alternatively, the initiator role within a PRS group may be assigned to an RSU located at a specific location. Additionally or alternatively, the initiator role within a PRS group may be assigned to a specific member of the PRS group based on the specific member having a fixed location or complete knowledge of the location. In some such implementations, the initiator includes an RSU or a PRS anchor vehicle. Additionally or alternatively, the initiator role within a PRS group may be assigned to a specific member of the PRS group that has the largest coverage area within the PRS group. Additionally or alternatively, the initiator role within a PRS group may be assigned to a specific member within the PRS group based on the specific member's determined location having the highest accuracy within the PRS group. Additionally or alternatively, the initiator role within a PRS group may be assigned to a specific member within the PRS group based on the specific member's estimated location having the highest accuracy within the PRS group.

[0139]

[0146] It should be noted that one or more blocks (or operations) described with reference to Figures 7 and 9 may be combined with one or more blocks (or operations) of another figure. For example, one or more blocks (or operations) of Figure 7 may be combined with one or more blocks (or operations) of Figure 9. As another example, one or more blocks of Figure 7 or Figure 9 may be combined with one or more blocks (or operations) of another one of Figures 2, 3, or 5. Additionally or alternatively, one or more operations described above with reference to Figures 1-9 may be combined with one or more operations described with reference to Figure 10.

[0140]

[0147] In some aspects of the present disclosure, techniques for enabling vehicle positioning using mmWave PRS may include additional aspects, such as any single aspect or any combination of aspects described with respect to one or more other processes or devices described below or elsewhere herein. In some aspects of the present disclosure, enabling vehicle positioning using mmWave PRS may include an apparatus transmitting, from an initiator of a PRS group to other members of the PRS group, an indication of access to a wireless channel for the PRS group. The apparatus may also broadcast a first PRS via each antenna beam of multiple antenna beams. The initiator's antenna array may be configured to communicate via the multiple antenna beams. In some implementations, the apparatus (e.g., the initiator) includes a wireless device such as an RSU or a UE. In some implementations, the apparatus may include at least one processor and a memory coupled to the processor. The processor may be configured to perform operations described herein with respect to the wireless device. In some other implementations, an apparatus may include a non-transitory computer-readable medium having program code recorded thereon, the program code being executable by a computer to cause the computer to perform the operations described herein with respect to the wireless device. In some implementations, an apparatus may include one or more means configured to perform the operations described herein.

[0141]

[0148] In a first aspect, the initiator includes an RSU.

[0142]

[0149] In a second aspect, the initiator includes a UE.

[0143]

[0150] In a third aspect, broadcasting the first PRS via each antenna beam of the plurality of antenna beams includes consecutively broadcasting the first PRS via each antenna beam of the plurality of antenna beams.

[0144]

[0151] In a fourth aspect, alone or in combination with one or more of the first through third aspects, the device uses the same sequence for each broadcast of the first PRS.

[0145]

[0152] In a fifth aspect, alone or in combination with one or more of the first through fourth aspects, the apparatus applies a different cyclic shift to each broadcast of the first PRS.

[0146]

[0153] In a sixth aspect, alone or in combination with one or more of the first through fifth aspects, broadcasting the first PRS comprises communicating in an mmWave band.

[0147]

[0154] In a seventh aspect, either alone or in combination with one or more of the first to sixth aspects, each antenna beam of the plurality of antenna beams is associated with an at least partially different direction.

[0148]

[0155] In an eighth aspect, alone or in combination with one or more of the first through seventh aspects, an apparatus receives a broadcast of a second PRS from a wireless communication device assigned a responder role in a PRS group.

[0149]

[0156] In a ninth aspect, in combination with the eighth aspect, the wireless communication device comprises a vehicle or a component of a vehicle.

[0150]

[0157] In a tenth aspect, alone or in combination with one or more of the eighth through ninth aspects, the apparatus transmits timing information to a wireless communication device after receiving a corresponding PRS broadcast from each remaining member included in the PRS group.

[0151]

[0158] In an eleventh aspect, in combination with the tenth aspect, the timing information comprises first antenna beam information indicating a transmission time of each broadcast of the first PRS and an antenna beam corresponding to each broadcast of the first PRS, and second antenna beam information indicating a reception time of the broadcast of the second PRS and an antenna beam corresponding to reception of the broadcast of the second PRS.

[0152]

[0159] In a twelfth aspect, alone or in combination with one or more of the tenth through eleventh aspects, an apparatus receives location data from a wireless communication device, the location data being based at least in part on timing information.

[0153]

[0160] In a thirteenth aspect, in combination with the twelfth aspect, the apparatus determines a measured clock error noise standard deviation at the initiator, a clock drift standard deviation at the initiator, or both, and transmits the measured clock error noise standard deviation, the clock drift standard deviation, or both to the wireless communication device prior to receiving the location data.

[0154]

[0161] In a fourteenth aspect, alone or in combination with one or more of the twelfth to thirteenth aspects, the apparatus determines an innovation measurement associated with a PRS measurement at the initiator and transmits the innovation measurement to the wireless communication device prior to receiving the location data.

[0155]

[0162] In a fifteenth aspect, alone or in combination with one or more of the eighth to ninth aspects, the apparatus receives timing information from a wireless communication device after receiving a corresponding PRS broadcast from each remaining member of the PRS group, determines location data indicating an estimated location of the wireless communication device based on the timing information, a transmission time of the broadcast of the first PRS via the antenna beam indicated by the timing information, and a reception time of the broadcast of the second PRS, and transmits the location data to the wireless communication device.

[0156]

[0163] In a sixteenth aspect, in combination with the fifteenth aspect, the apparatus determines clock information for the wireless communication device based on the initiator's clock signal and timing information, and transmits the clock information to the wireless communication device.

[0157]

[0164] In a seventeenth aspect, alone or in combination with one or more of the fifteenth to sixteenth aspects, the timing information from the wireless communication device comprises: a reception time of a broadcast of a first PRS at the wireless communication device; antenna beam information indicating an antenna beam corresponding to the reception of the broadcast of the first PRS at the wireless communication device; and second antenna beam information indicating a transmission time of one or more broadcasts of a second PRS by the wireless communication device; and antenna beam information indicating an antenna beam corresponding to the broadcast of the second PRS.

[0158]

[0165] In an eighteenth aspect, alone or in combination with one or more of the fifteenth to seventeenth aspects, the apparatus receives velocity information from the wireless communication device, and the location data is further based on the velocity information.

[0159]

[0166] In a nineteenth aspect, alone or in combination with one or more of the fifteenth through eighteenth aspects, an apparatus receives, from a wireless communication device, a measured clock error noise standard deviation at the wireless communication device, a clock drift standard deviation at the wireless communication device, or both, and the location data is further based on the measured clock error noise standard deviation, the clock drift standard deviation, or both.

[0160]

[0167] In a twentieth aspect, alone or in combination with one or more of the fifteenth through nineteenth aspects, an apparatus receives, from a wireless communication device, innovation measurements related to PRS measurements at the wireless communication device, and the location data is further based on the innovation measurements.

[0161]

[0168] In a 21st aspect, alone or in combination with one or more of the first to 20th aspects, a device transmits a PRS broadcast sequence associated with a PRS group to other members of the PRS group, the PRS broadcast sequence indicating a sequence designated for members of the PRS group to broadcast corresponding PRS signals.

[0162]

[0169] In a twenty-second aspect, alone or in combination with one or more of the first to twenty-first aspects, an apparatus receives, from a member of a PRS group, the number of antenna beams used by the member of the PRS group.

[0163]

[0170] In a twenty-third aspect, in combination with the twenty-second aspect, the apparatus transmits, to other members of the PRS group, an indication of a CoT of the PRS group over a wireless channel, the CoT being based on a total number of antenna beams used by all members of the PRS group.

[0164]

[0171] In a twenty-fourth aspect, alone or in combination with one or more of the first to twenty-third aspects, roles within a PRS group are assigned via higher layer signaling between members of the PRS group.

[0165]

[0172] In a twenty-fifth aspect, alone or in combination with one or more of the first to twenty-fourth aspects, an initiator role in a PRS group is assigned to an RSU located at a specific location.

[0166]

[0173] In a twenty-sixth aspect, alone or in combination with one or more of the first through twenty-fifth aspects, the initiator role in a PRS group is assigned to a particular member of the PRS group based on the particular member having a fixed location or complete knowledge of the location.

[0167]

[0174] In a twenty-seventh aspect, in combination with the twenty-sixth aspect, the initiator comprises an RSU or a PRS anchor vehicle.

[0168]

[0175] In a 28th aspect, either alone or in combination with one or more of the first to twenty-seventh aspects, the initiator role in a PRS group is assigned to a particular member of the PRS group that has the largest coverage area within the PRS group.

[0169]

[0176] In a 29th aspect, alone or in combination with one or more of the first through 28th aspects, the initiator role in the PRS group is assigned to a particular member in the PRS group based on the particular member's determined position having the highest accuracy within the PRS group.

[0170]

[0177] In a thirtieth aspect, alone or in combination with one or more of the first to twenty-ninth aspects, the initiator role in a PRS group is assigned to a particular member in the PRS group based on the particular member's estimated location having the highest accuracy within the PRS group.

[0171]

[0178] In some aspects of the present disclosure, an apparatus configured for wireless communication is configured to receive, at a responder of the PRS group, an indication of access to a wireless channel for the PRS group from an initiator of the PRS group. The apparatus is also configured to receive a broadcast of a first PRS from the initiator. The apparatus is also configured to determine whether any other members of the PRS group are scheduled for PRS broadcast before the responder. The apparatus is further configured to broadcast a second PRS via each antenna beam of the one or more antenna beams based on a determination that no other members of the PRS group are scheduled for broadcast before the responder. The antenna array of the responder may be configured to communicate via the one or more antenna beams. In some implementations, the apparatus (e.g., the responder) includes a wireless device such as a UE or an RSU. In some implementations, the apparatus may include at least one processor and a memory coupled to the processor. The processor may be configured to perform operations described herein with respect to the wireless device. In some other implementations, an apparatus may include a non-transitory computer-readable medium having program code recorded thereon, the program code being executable by a computer to cause the computer to perform the operations described herein with respect to the wireless device. In some implementations, an apparatus may include one or more means configured to perform the operations described herein.

[0172]

[0179] In a thirty-first aspect, the responder includes a UE.

[0173]

[0180] In a thirty-second aspect, the responder includes an RSU.

[0174]

[0181] In a 33rd aspect, alone or in combination with one or more of the 31st to 32nd aspects, broadcasting the second PRS via each antenna beam of the one or more antenna beams includes continuously broadcasting the second PRS via each antenna beam of the one or more antenna beams.

[0175]

[0182] In a thirty-fourth aspect, alone or in combination with one or more of the thirty-first to thirty-third aspects, the apparatus uses the same sequence for each broadcast of the second PRS.

[0176]

[0183] In a thirty-fifth aspect, alone or in combination with one or more of the thirty-first through thirty-fourth aspects, the apparatus applies a different cyclic shift to each broadcast of the second PRS.

[0177]

[0184] In a thirty-sixth aspect, alone or in combination with one or more of the thirty-first through thirty-fifth aspects, broadcasting the second PRS comprises communicating in an mmWave band.

[0178]

[0185] In a 37th aspect, alone or in combination with one or more of the 31st to 36th aspects, each antenna beam of the one or more antenna beams is associated with at least a partially different direction.

[0179]

[0186] In a thirty-eighth aspect, alone or in combination with one or more of the thirty-first to thirty-seventh aspects, the initiator comprises an RSU.

[0180]

[0187] In a thirty-ninth aspect, alone or in combination with one or more of the thirty-first to thirty-eighth aspects, an apparatus receives, from an initiator, a PRS broadcast sequence associated with a PRS group and a number of antenna beams corresponding to each member of the PRS group, wherein the PRS broadcast sequence indicates a sequence in which members of the PRS group are designated to broadcast corresponding PRS signals.

[0181]

[0188] In a fortieth aspect, in combination with the thirty-ninth aspect, determining whether any other members of the PRS group are scheduled for a PRS broadcast before the responder comprises determining whether the most recently received PRS broadcast was received from a particular member of the PRS group that immediately precedes the responder in the PRS broadcast sequence.

[0182]

[0189] In a forty-first aspect, in combination with the fortieth aspect, determining whether any other members of the PRS group are scheduled for PRS broadcast before the responder further comprises determining whether the particular member has completed PRS broadcasting based on a cyclic shift associated with a most recently received PRS broadcast and the number of antenna beams associated with the particular member.

[0183]

[0190] In a forty-second aspect, alone or in combination with one or more of the thirty-first to forty-first aspects, the device receives timing information from the initiator after receiving a corresponding PRS broadcast from each remaining member of the PRS group.

[0184]

[0191] In a 43rd aspect, in combination with the 42nd aspect, the timing information from the initiator comprises first antenna beam information indicating a transmission time of each broadcast of the first PRS and an antenna beam of the initiator corresponding to each broadcast of the second PRS, and second antenna beam information indicating a reception time of the broadcast of the second PRS at the initiator and an antenna beam corresponding to reception of the broadcast of the second PRS at the initiator.

[0185]

[0192] In a 44th aspect, in combination with the 43rd aspect, the device determines location data indicating an estimated location of the responder based on the timing information, the reception time of the broadcast of the first PRS, and the transmission time of the broadcast of the second PRS via the antenna beam indicated by the second antenna beam information, and transmits the location data to the initiator.

[0186]

[0193] In a 45th aspect, alone or in combination with one or more of the 43rd to 44th aspects, the device determines a measured clock error noise standard deviation at the responder, a clock drift standard deviation at the responder, or both, and transmits the measured clock error noise standard deviation, the clock drift standard deviation, or both to the initiator.

[0187]

[0194] In a 46th aspect, alone or in combination with one or more of aspects 43 to 45, the device determines an innovation measurement associated with the PRS measurement at the responder and transmits the innovation measurement to the initiator.

[0188]

[0195] In a forty-seventh aspect, alone or in combination with one or more of the thirty-first to forty-first aspects, the device transmits timing information to the initiator after receiving a corresponding PRS broadcast from each remaining member of the PRS group, the timing information indicating a reception time of the broadcast of the first PRS and antenna beam information indicating an antenna beam corresponding to the broadcast of the first PRS, and a transmission time of the broadcast of the second PRS and second antenna beam information indicating an antenna beam corresponding to the broadcast of the second PRS.

[0189]

[0196] In a forty-eighth aspect, in combination with the forty-seventh aspect, the device receives location data from the initiator, the location data indicating an estimated location of the responder.

[0190]

[0197] In a forty-ninth aspect, in combination with the forty-eighth aspect, the device determines velocity information associated with the transponder and transmits the velocity information to the initiator prior to receiving the location data.

[0191]

[0198] In a 50th aspect, alone or in combination with one or more of the 48th to 49th aspects, the device determines a measured clock error noise standard deviation at the responder, a clock drift standard deviation at the responder, or both, and transmits the measured clock error noise standard deviation, the clock drift standard deviation, or both, to the initiator prior to receiving the location data.

[0192]

[0199] In a 51st aspect, alone or in combination with one or more of aspects 48 to 50, the device determines an innovation measurement associated with a PRS measurement at the responder and transmits the innovation measurement to the initiator prior to receiving the location data.

[0193]

[0200] In a 52nd aspect, alone or in combination with one or more of the 48th to 51st aspects, an apparatus receives clock information from an initiator, the clock information indicating a clock signal to be used by a responder.

[0194]

[0201] In a 53rd aspect, either alone or in combination with one or more of the 31st to 52nd aspects, the device transmits to the initiator the number of antenna beams included in the one or more antenna beams.

[0195]

[0202] In a fifty-fourth aspect, in combination with the fifty-third aspect, an apparatus receives, from an initiator, an indication of a CoT of a PRS group over a wireless channel, the CoT being based on a total number of antenna beams used by all members of the PRS group.

[0196]

[0203] In a 55th aspect, alone or in combination with one or more of the 31st to 54th aspects, roles within a PRS group are assigned via higher layer signaling between members of the PRS group.

[0197]

[0204] In a 56th aspect, alone or in combination with one or more of the 31st to 55th aspects, an initiator role in a PRS group is assigned to an RSU located at a specific location.

[0198]

[0205] In a 57th aspect, alone or in combination with one or more of the 31st to 56th aspects, the initiator role in a PRS group is assigned to a particular member of the PRS group based on the particular member having a fixed location or complete knowledge of the location.

[0199]

[0206] In a 58th aspect, in combination with the 57th aspect, the initiator comprises an RSU or a PRS anchor vehicle.

[0200]

[0207] In a 59th aspect, alone or in combination with one or more of the 31st to 58th aspects, the initiator role in a PRS group is assigned to a particular member of the PRS group that has the largest coverage area within the PRS group.

[0201]

[0208] In a 60th aspect, alone or in combination with one or more of the 31st to 59th aspects, the initiator role in the PRS group is assigned to a particular member in the PRS group based on the particular member's determined position having the highest accuracy within the PRS group.

[0202]

[0209] In a 61st aspect, alone or in combination with one or more of the 31st to 60th aspects, the initiator role in a PRS group is assigned to a particular member in the PRS group based on the particular member's estimated location having the highest accuracy within the PRS group.

[0203]

[0210] Those skilled in the art will understand that information and signals may be represented using any of a variety of different technologies and techniques. For example, data, instructions, commands, information, signals, bits, symbols, and chips that may be referred to throughout the above description may be represented by voltages, currents, electromagnetic waves, magnetic fields or particles, optical fields or particles, or any combination thereof. Furthermore, use of "positioning reference signal" or "PRS" herein, unless otherwise specified, is intended to represent all or part of one or more signals that may be used, at least in part, for positioning purposes, such as position determination or estimation, or other examples. Thus, those skilled in the art will recognize that, unless otherwise specified, PRS as used herein need not necessarily be limited to representing a particular signal or message scheme in a given communications standard, etc.

[0204]

[0211] The components, functional blocks, and modules described herein (e.g., the components, functional blocks, and modules of FIGS. 2, 5, 8, and 10) may comprise processors, electronics devices, hardware devices, electronics components, logic circuits, memory, software code, firmware code, etc., or any combination thereof. Additionally, the features discussed herein in connection with FIGS. 1-10 may be implemented via dedicated processor circuitry, via executable instructions, or a combination thereof.

[0205]

[0212] Those skilled in the art will further appreciate that the various illustrative logic blocks, modules, circuits, and algorithm steps described in connection with the disclosure herein (e.g., the logic blocks of FIGS. 7 and 9 ) can be implemented as electronic hardware, computer software, or a combination of both. To clearly illustrate this interchangeability of hardware and software, various illustrative components, blocks, modules, circuits, and steps have been described above generally in terms of their functionality. Whether such functionality is implemented as hardware or software depends on the particular application and design constraints imposed on the overall system. Those skilled in the art may implement the described functionality in varying ways for each particular application, but such implementation decisions should not be interpreted as causing a departure from the scope of the present disclosure. Those skilled in the art will also readily recognize that the ordering or combination of components, methods, or interactions described herein are merely examples, and that the components, methods, or interactions of various aspects of the disclosure can be combined or performed in ways other than those illustrated and described herein.

[0206]

[0213] The various example logic blocks, modules, and circuits described in connection with the disclosure herein may be implemented or performed using a general-purpose processor, a digital signal processor (DSP), an application-specific integrated circuit (ASIC), a field-programmable gate array (FPGA) or other programmable logic device, discrete gate or transistor logic, discrete hardware components, or any combination thereof designed to perform the functions described herein. A general-purpose processor may be a microprocessor, but alternatively, the processor may be any conventional processor, controller, microcontroller, or state machine. A processor may also be implemented as a combination of computing devices, e.g., a combination of a DSP and a microprocessor, multiple microprocessors, one or more microprocessors in conjunction with a DSP core, or any other such configuration.

[0207]

[0214] The steps of a method or algorithm described in connection with the disclosure herein may be embodied directly in hardware, in a software module executed by a processor, or in a combination of the two. A software module may reside in RAM memory, flash memory, ROM memory, EPROM memory, EEPROM memory, registers, a hard disk, a removable disk, a CD-ROM, or any other form of storage medium known in the art. An exemplary storage medium is coupled to the processor such that the processor can read information from, and write information to, the storage medium. Alternatively, the storage medium may be integral to the processor. The processor and the storage medium may reside in an ASIC. The ASIC may reside in a user terminal. Alternatively, the processor and the storage medium may reside as discrete components in a user terminal.

[0208]

[0215] In one or more exemplary designs, the functions described may be implemented in hardware, software, firmware, or any combination thereof. If implemented in software, the functions may be stored on or transmitted over as one or more instructions or code on a computer-readable medium. Computer-readable media includes both computer storage media and communication media, including any medium that facilitates transfer of a computer program from one place to another. Computer-readable storage media may be any available medium that can be accessed by a general-purpose or special-purpose computer. By way of example, and not limitation, such computer-readable media may 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 carry or store desired program code means in the form of instructions or data structures and that can be accessed by a general-purpose or special-purpose computer or a general-purpose or special-purpose processor. As used herein, disk and disc include compact discs (CDs), laser discs, optical discs, digital versatile discs (DVDs), hard disks, solid state disks, and Blu-ray discs, where disks typically reproduce data magnetically and discs reproduce data optically with lasers. Combinations of the above should also be included within the scope of computer-readable media.

[0209]

[0216] As used herein, including the claims, the term "and / or," when used in a list of two or more items, means that any one of the listed items may be employed alone, or that any combination of two or more of the listed items may be employed. For example, if a composition is described as including components A, B, and / or C, the composition may include A only, B only, C only, a combination of A and B, a combination of A and C, a combination of B and C, or a combination of A, B, and C. Also, as used herein, including the claims, "or" used in a list of items ending with "at least one of" indicates a disjunctive list, such as, for example, a list of "at least one of A, B, or C" means any of A or B or C or AB or AC or BC or ABC (i.e., A and B and C), or any of these in any combination thereof.

[0210]

[0217] The previous description of the disclosure is provided to enable any person skilled in the art to make or use the disclosure. Various modifications to the disclosure will be readily apparent to those skilled in the art, and the general principles defined herein may be applied to other variations without departing from the spirit or scope of the disclosure. Thus, the disclosure is not intended to be limited to the examples and designs described herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein. The inventions described in the claims of the present application as originally filed are set forth below. [C1] 1. A method of wireless communication, comprising: transmitting an indication from an initiator of a positioning reference signal (PRS) group to other members of the PRS group of access to a wireless channel for the PRS group; broadcasting a first PRS via each antenna beam of a plurality of antenna beams, wherein an antenna array of the initiator is configured to communicate via the plurality of antenna beams; A method comprising: [C2] The method of C1, wherein broadcasting the first PRS via each antenna beam of the plurality of antenna beams comprises continuously broadcasting the first PRS via each antenna beam of the plurality of antenna beams. [C3] The method of C1, further comprising using the same sequence for each broadcast of the first PRS. [C4] The method of C1, further comprising applying a different cyclic shift to each broadcast of the first PRS. [C5] receiving a broadcast of a second PRS from a wireless communication device assigned a responder role in the PRS group, the wireless communication device comprising a vehicle or a component of a vehicle; transmitting timing information to the wireless communication device after receiving a corresponding PRS broadcast from each remaining member of the PRS group; The method of C1, further comprising: [C6] The method of C5, wherein the timing information comprises a transmission time of each broadcast of the first PRS, first antenna beam information indicating the antenna beam corresponding to each broadcast of the first PRS, a reception time of the broadcast of the second PRS, and second antenna beam information indicating the antenna beam corresponding to reception of the broadcast of the second PRS. [C7] The method of C5, further comprising receiving location data from the wireless communication device, the location data based at least in part on the timing information. [C8] determining a measured clock error noise standard deviation at the initiator, a clock drift standard deviation at the initiator, or both; transmitting the measured clock error noise standard deviation, the clock drift standard deviation, or both to the wireless communication device prior to receiving the location data; The method of C7, further comprising: [C9] determining an innovation measure associated with a PRS measure at the initiator; transmitting the innovation measurements to the wireless communication device prior to receiving the location data; The method of C7, further comprising: [C10] 5. The method of claim 1, further comprising transmitting to the other members of the PRS group a PRS broadcast sequence associated with the PRS group, the PRS broadcast sequence indicating an order in which members of the PRS group are designated to broadcast corresponding PRS signals. [C11] receiving from a member of the PRS group the number of antenna beams used by the member of the PRS group; transmitting to the other members of the PRS group an indication of a channel occupation time (CoT) of the PRS group on the wireless channel, the CoT being based on a total number of antenna beams used by all members of the PRS group; The method of C1, further comprising: [C12] The initiator role in the PRS group is assigned to a particular member of the PRS group: The particular member is a roadside unit (RSU) located at a particular location; The particular member has a fixed location or complete knowledge of the location; the particular member has the largest coverage area within the PRS group; the determined position of said particular member has the highest accuracy within said PRS group; or the estimated location of the particular member has the highest accuracy within the PRS group; The method according to C1, which is assigned based on [C13] 1. An apparatus configured for wireless communication, comprising: at least one processor; a memory coupled to the at least one processor; wherein the at least one processor: transmitting an indication from an initiator of a positioning reference signal (PRS) group to other members of the PRS group of access to a wireless channel for the PRS group; broadcasting a first PRS via each antenna beam of a plurality of antenna beams, wherein an antenna array of the initiator is configured to communicate via the plurality of antenna beams; An apparatus configured to: [C14] The apparatus of C13, wherein each antenna beam of the plurality of antenna beams is associated with at least a partially different direction. [C15] The at least one processor: receiving a broadcast of a second PRS from a wireless communication device assigned a responder role in the PRS group; receiving timing information from the wireless communication device after receiving a corresponding PRS broadcast from each remaining member of the PRS group; determining location data indicative of an estimated location of the wireless communication device based on the timing information, a transmission time of the broadcast of the first PRS, and a reception time of the broadcast of the second PRS via an antenna beam indicated by the timing information; transmitting the location data to the wireless communication device; The apparatus of C13, further configured to: [C16] The at least one processor: determining clock information for the wireless communication device based on the initiator's clock signal and the timing information; transmitting the clock information to the wireless communication device; The apparatus of C15, further configured to: [C17] 16. The apparatus of claim 15, wherein the timing information from the wireless communication device comprises: a reception time of a broadcast of the first PRS at the wireless communication device; antenna beam information indicating the antenna beam corresponding to the reception of the broadcast of the first PRS at the wireless communication device; and second antenna beam information indicating a transmission time of one or more broadcasts of the second PRS by the wireless communication device and at least one antenna beam corresponding to the broadcast of the second PRS. [C18] The apparatus of C15, wherein the at least one processor is further configured to receive speed information from the wireless communication device, and the location data is further based on the speed information. [C19] The apparatus of C15, wherein the at least one processor is further configured to receive from the wireless communication device a measured clock error noise standard deviation at the wireless communication device, a clock drift standard deviation at the wireless communication device, or both, and the location data is further based on the measured clock error noise standard deviation, the clock drift standard deviation, or both. [C20] The apparatus of C15, wherein the at least one processor is further configured to receive from the wireless communication device an innovation measurement associated with a PRS measurement at the wireless communication device, and the location data is further based on the innovation measurement. [C21] 1. A method of wireless communication, comprising: receiving, at a transponder of a positioning reference signal (PRS) group, from an initiator of the PRS group, an indication of access to a wireless channel for the PRS group; receiving a broadcast of a first PRS from the initiator; determining whether any other members of the PRS group are scheduled for PRS broadcast before the responder; broadcasting a second PRS via each antenna beam of one or more antenna beams based on a determination that other members of the PRS group are not scheduled for broadcast before the transponder, wherein an antenna array of the transponder is configured to communicate via the one or more antenna beams. A method comprising: [C22] The method of C21, wherein broadcasting the second PRS via each antenna beam of the one or more antenna beams comprises continuously broadcasting the second PRS via each antenna beam of the one or more antenna beams, and broadcasting the second PRS comprises communicating in a millimeter wave (mmWave) band. [C23] using the same sequence for each broadcast of said second PRS; or The method of C21, further comprising: applying a different cyclic shift to each broadcast of the second PRS. [C24] 2. The method of claim 1, further comprising receiving from the initiator a PRS broadcast sequence associated with the PRS group and a number of antenna beams corresponding to each member of the PRS group, the PRS broadcast sequence indicating an order in which members of the PRS group are designated to broadcast corresponding PRS signals. [C25] Determining whether any other members of the PRS group are scheduled for PRS broadcast before the responder includes: determining whether a most recently received PRS broadcast was received from a particular member of the PRS group that immediately precedes the responder in the PRS broadcast sequence; determining whether the particular member has completed PRS broadcasting based on a cyclic shift associated with the most recently received PRS broadcast and a number of antenna beams associated with the particular member; The method of claim C24, comprising: [C26] 1. An apparatus configured for wireless communication, comprising: at least one processor; a memory coupled to the at least one processor; wherein the at least one processor: receiving, at a transponder of a positioning reference signal (PRS) group, from an initiator of the PRS group, an indication of access to a wireless channel for the PRS group; receiving a broadcast of a first PRS from the initiator; determining whether any other members of the PRS group are scheduled for PRS broadcast before the responder; broadcasting a second PRS via each antenna beam of one or more antenna beams based on a determination that other members of the PRS group are not scheduled for broadcast before the transponder, wherein an antenna array of the transponder is configured to communicate via the one or more antenna beams. An apparatus configured to: [C27] The at least one processor: receiving timing information from the initiator after receiving a corresponding PRS broadcast from each remaining member of the PRS group, the timing information from the initiator comprising: a transmission time of each broadcast of the first PRS, first antenna beam information indicating an antenna beam of the initiator corresponding to each broadcast of the second PRS, a reception time at the initiator of the broadcast of the second PRS, and second antenna beam information indicating the antenna beam corresponding to reception of the broadcast of the second PRS at the initiator; determining location data indicative of an estimated location of the transponder based on the timing information, a reception time of the broadcast of the first PRS, and a transmission time of the broadcast of the second PRS via the antenna beam indicated by the second antenna beam information; transmitting the location data to the initiator; The apparatus of C26, further configured to: [C28] The at least one processor: commencing transmission of timing information to the initiator after receiving a corresponding PRS broadcast from each remaining member of the PRS group, the timing information indicating a reception time of the broadcast of the first PRS, antenna beam information indicating an antenna beam corresponding to the broadcast of the first PRS, a transmission time of the broadcast of the second PRS, and second antenna beam information indicating the antenna beam corresponding to the broadcast of the second PRS. receiving location data from the initiator, the location data indicating an estimated location of the responder; The apparatus of C26, further configured to: [C29] The at least one processor: determining rate information associated with the responder, a measured clock error noise standard deviation at the responder, a clock drift standard deviation at the responder, an innovation measurement associated with a PRS measurement at the responder, or a combination thereof; Initiating transmission of the speed information, the measured clock error noise standard deviation, the clock drift standard deviation, the innovation measurement, or a combination thereof to the initiator prior to receiving position data from the initiator; The apparatus of C28, further configured to: [C30] The at least one processor: initiating transmission of a number of antenna beams included in the one or more antenna beams to the initiator; receiving, from the initiator, an indication of a channel occupation time (CoT) of the PRS group on the wireless channel, the CoT being based on a total number of antenna beams used by all members of the PRS group; The apparatus of C26, further configured to:

Claims

1. 1. A method of wireless communication, comprising: transmitting an indication of access to a wireless channel for the positioning reference signal (PRS) group from an initiator of the PRS group to other members of the PRS group, wherein the indication of access indicates information related to access to the wireless channel for the members of the PRS group to perform PRS broadcasts on the wireless channel; broadcasting a first PRS over the wireless channel via each antenna beam of a plurality of antenna beams, wherein an antenna array of the initiator is configured to communicate via the plurality of antenna beams; A method comprising:

2. 2. The method of claim 1, wherein broadcasting the first PRS via each antenna beam of the plurality of antenna beams comprises consecutively broadcasting the first PRS via each antenna beam of the plurality of antenna beams.

3. The method of claim 1 , further comprising using the same sequence for each broadcast of the first PRS.

4. 10. The method of claim 1, further comprising applying a different cyclic shift to each broadcast of the first PRS.

5. receiving a broadcast of a second PRS from a wireless communication device assigned a responder role in the PRS group, the wireless communication device comprising a vehicle or a component of a vehicle; transmitting timing information to the wireless communication device after receiving a corresponding PRS broadcast from each remaining member of the PRS group; The method of claim 1 further comprising:

6. 6. The method of claim 5, wherein the timing information comprises: a transmission time of each broadcast of the first PRS; first antenna beam information indicating the antenna beam corresponding to each broadcast of the first PRS; a reception time of the broadcast of the second PRS; and second antenna beam information indicating the antenna beam corresponding to reception of the broadcast of the second PRS.

7. 6. The method of claim 5, further comprising receiving location data from the wireless communication device, the location data based at least in part on the timing information.

8. determining a measured clock error noise standard deviation at the initiator, a clock drift standard deviation at the initiator, or both; transmitting the measured clock error noise standard deviation, the clock drift standard deviation, or both to the wireless communication device prior to receiving the location data; The method of claim 7 further comprising:

9. determining an innovation measurement associated with a PRS measurement at the initiator; transmitting the innovation measurements to the wireless communication device prior to receiving the location data; The method of claim 7 further comprising:

10. 1. An apparatus configured for wireless communication, comprising: at least one processor; a memory coupled to the at least one processor; wherein the at least one processor transmitting an indication of access to a wireless channel for the positioning reference signal (PRS) group from an initiator of the PRS group to other members of the PRS group, wherein the indication of access indicates information related to access to the wireless channel for the members of the PRS group to perform PRS broadcasts on the wireless channel; broadcasting a first PRS over the wireless channel via each antenna beam of a plurality of antenna beams, wherein an antenna array of the initiator is configured to communicate via the plurality of antenna beams; An apparatus configured to:

11. The apparatus of claim 10 , wherein each antenna beam of the plurality of antenna beams is associated with at least a partially different direction.

12. The at least one processor receiving a broadcast of a second PRS from a wireless communication device assigned a responder role in the PRS group; receiving timing information from the wireless communication device after receiving a corresponding PRS broadcast from each remaining member of the PRS group; determining location data indicative of an estimated location of the wireless communication device based on the timing information, a transmission time of the broadcast of the first PRS and a reception time of the broadcast of the second PRS via an antenna beam indicated by the timing information; transmitting the location data to the wireless communication device; The apparatus of claim 10 , further configured to:

13. 1. A method of wireless communication, comprising: receiving, at a positioning reference signal (PRS) group responder, from an initiator of the PRS group, an indication of access to a wireless channel for the PRS group, wherein the indication of access indicates information related to access to the wireless channel for members of the PRS group to conduct PRS broadcasts on the wireless channel; receiving a broadcast of a first PRS over the wireless channel from the initiator; determining whether any other members of the PRS group are scheduled for PRS broadcast before the responder on the wireless channel; broadcasting a second PRS over the wireless channel via each antenna beam of one or more antenna beams based on a determination that other members of the PRS group are not scheduled for broadcast before the responder, wherein an antenna array of the responder is configured to communicate via the one or more antenna beams. A method comprising:

14. 1. An apparatus configured for wireless communication, comprising: at least one processor; a memory coupled to the at least one processor; wherein the at least one processor receiving, at a positioning reference signal (PRS) group responder, from an initiator of the PRS group, an indication of access to a wireless channel for the PRS group, wherein the indication of access indicates information related to access to the wireless channel for members of the PRS group to conduct PRS broadcasts on the wireless channel; receiving a broadcast of a first PRS over the wireless channel from the initiator; determining whether any other members of the PRS group are scheduled for PRS broadcast before the responder on the wireless channel; broadcasting a second PRS over the wireless channel via each antenna beam of one or more antenna beams based on a determination that other members of the PRS group are not scheduled for broadcast before the responder, wherein an antenna array of the responder is configured to communicate via the one or more antenna beams. An apparatus configured to:

15. 10. A non-transitory computer readable medium configured to store instructions that, when executed by a processor, cause the processor to perform the steps of the method of any one of claims 1 to 9.

16. A non-transitory computer-readable medium configured to store instructions that, when executed by a processor, cause the processor to perform the steps of the method of claim 13.

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