Location Assistance Data for Reconfigurable Intelligent Surface-Aided Positioning

Abstract

Techniques for communication are disclosed. In one aspect, a network component determines location assistance data comprising information associated with one or more reconfigurable intelligent surfaces (RISs). The network component transmits the location assistance data to a user equipment (UE) to facilitate one or more location procedures based on the location assistance data. The UE receives the location assistance data and performs one or more location procedures based on the location assistance data.

Description

[Technical Field]

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS This patent application claims the benefit of Greek Application No. 20210100169, entitled "LOCATION ASSISTANCE DATA FOR RECONFIGURABLE INTELLIGENT SURFACE AIDED POSITIONING," filed March 17, 2021, which is assigned to the assignee of the present application and is expressly incorporated herein by reference in its entirety.

[0002] Aspects of the present disclosure relate generally to wireless communications. [Background technology]

[0003] Wireless communication systems have evolved through various generations, including first-generation analog wireless telephone service (1G), second-generation (2G) digital wireless telephone service (including interim 2.5G and 2.75G networks), third-generation (3G) high-speed data, Internet-enabled wireless service, and fourth-generation (4G) service (e.g., Long Term Evolution (LTE) or WiMax). Currently, there are many different types of wireless communication systems in use, including cellular systems and personal communications services (PCS) systems. Examples of known cellular systems include the Cellular Analog Advanced Mobile Phone System (AMPS), and digital cellular systems based on code division multiple access (CDMA), frequency division multiple access (FDMA), time division multiple access (TDMA), Global System for Mobile Communications (GSM), etc.

[0004] The fifth-generation (5G) wireless standard, known as New Radio (NR), promises higher data rates, more connections, and better coverage, among other improvements. According to the Next Generation Mobile Network Alliance, the 5G standard is designed to provide data rates of tens of megabits per second to each of tens of thousands of users, delivering 1 gigabit per second to dozens of workers on an office floor. To support large-scale sensor deployments, hundreds of thousands of simultaneous connections should be supported. Therefore, the spectral efficiency of 5G mobile communications should be significantly enhanced compared to the current 4G standard. Furthermore, signaling efficiency should be enhanced and latency significantly reduced compared to current standards. Summary of the Invention [Means for solving the problem]

[0005] The following presents a simplified summary related to one or more aspects disclosed herein. As such, the following summary is not intended to be an extensive overview related to all contemplated aspects, nor is it intended to identify key or critical elements related to all contemplated aspects or to delineate the scope related to any particular aspect. As such, the following summary has the sole purpose of presenting some concepts related to one or more aspects related to the mechanisms disclosed herein in a simplified form prior to the detailed description presented below.

[0006] In one aspect, a method of operating a user equipment (UE) includes receiving location assistance data from a network component, the location assistance data comprising information related to one or more reconfigurable intelligent surfaces (RISs), and performing one or more location procedures based on the location assistance data.

[0007] In one aspect, a method of operating a network component includes determining location assistance data comprising information associated with one or more reconfigurable intelligent surfaces (RISs) and transmitting the location assistance data to a user equipment (UE) to facilitate one or more location procedures based on the location assistance data.

[0008] In one aspect, a user equipment (UE) includes a memory, at least one transceiver, and at least one processor communicatively coupled to the memory and the at least one transceiver, wherein the at least one processor is configured to receive location assistance data from a network component, the location assistance data comprising information related to one or more reconfigurable intelligent surfaces (RISs), and to perform one or more location procedures based on the location assistance data.

[0009] In one aspect, the network component includes a memory, at least one transceiver, and at least one processor communicatively coupled to the memory and the at least one transceiver, wherein the at least one processor is configured to determine location assistance data comprising information associated with one or more reconfigurable intelligent surfaces (RISs) and transmit the location assistance data to a user equipment (UE) to facilitate one or more location procedures based on the location assistance data.

[0010] In one aspect, a user equipment (UE) includes means for receiving location assistance data from a network component, the location assistance data comprising information related to one or more reconfigurable intelligent surfaces (RISs), and means for performing one or more location procedures based on the location assistance data.

[0011] In one aspect, a network component includes means for determining location assistance data comprising information related to one or more reconfigurable intelligent surfaces (RISs) and means for transmitting the location assistance data to a user equipment (UE) to facilitate one or more location procedures based on the location assistance data.

[0012] In one aspect, a non-transitory computer-readable medium storing computer-executable instructions that, when executed by a user equipment (UE), cause the UE to receive location assistance data from a network component, the location assistance data comprising information related to one or more reconfigurable intelligent surfaces (RISs), and perform one or more location procedures based on the location assistance data.

[0013] In one aspect, a non-transitory computer-readable medium storing computer-executable instructions that, when executed by a network component, cause the network component to determine location assistance data comprising information associated with one or more reconfigurable intelligent surfaces (RISs) and transmit the location assistance data to a user equipment (UE) to facilitate one or more location procedures based on the location assistance data.

[0014] Other objects and advantages associated with the embodiments disclosed herein will become apparent to those skilled in the art based on the accompanying drawings and detailed description.

[0015] The accompanying drawings are presented to aid in the explanation of various aspects of the present disclosure and are provided solely for the purpose of illustrating the aspects and not for the purpose of limiting the aspects. [Brief explanation of the drawings]

[0016] [Figure 1] FIG. 1 illustrates an exemplary wireless communication system according to aspects of the present disclosure. [Figure 2A] FIG. 1 illustrates an exemplary wireless network structure according to aspects of the present disclosure. [Figure 2B] FIG. 1 illustrates an exemplary wireless network structure according to aspects of the present disclosure. [Figure 3A] 1 is a simplified block diagram of several sample aspects of components that may be employed in a user equipment (UE) and configured to support communication as taught herein; [Figure 3B] 1 is a simplified block diagram of several sample aspects of components that may be employed in a base station and configured to support communication as taught herein; [Figure 3C] 1 is a simplified block diagram of several sample aspects of components that may be employed in a network entity and configured to support communications as taught herein; [Figure 4A] FIG. 2 illustrates an exemplary frame structure according to aspects of the present disclosure. [Figure 4B] FIG. 1 illustrates an example channel within a frame structure according to an aspect of the present disclosure. [Figure 4C] FIG. 2 illustrates an exemplary frame structure according to aspects of the present disclosure. [Figure 4D] FIG. 1 illustrates an example channel within a frame structure according to an aspect of the present disclosure. [Figure 5] FIG. 1 illustrates an exemplary base station communicating with an exemplary UE, according to aspects of the present disclosure. [Figure 6] FIG. 1 illustrates an example system for wireless communication using a reconfigurable intelligent surface (RIS), according to aspects of the present disclosure. [Figure 7] FIG. 2 is a diagram of an example architecture of a RIS, according to an aspect of the present disclosure. [Figure 8] FIG. 1 illustrates an exemplary process for communication according to an aspect of the present disclosure. [Figure 9] FIG. 10 illustrates an exemplary process for communication according to another aspect of the present disclosure. [Figure 10] FIG. 1 illustrates a configuration by which boresight may be derived, according to one aspect of the present disclosure. DETAILED DESCRIPTION OF THE INVENTION

[0017] Aspects of the present disclosure are provided in the following description and related drawings, directed to various examples provided for illustrative purposes. Alternative aspects may be devised without departing from the scope of the present disclosure. Additionally, well-known elements of the present disclosure will not be described in detail or will be omitted so as not to obscure the relevant details of the present disclosure.

[0018] The words "exemplary" and / or "example" are used herein to mean "serving as an example, instance, or illustration." Any aspect described herein as "exemplary" and / or "example" is not necessarily to be construed as preferred or advantageous over other aspects. Likewise, the term "aspects of the present disclosure" does not require that all aspects of the present disclosure include the discussed feature, advantage or mode of operation.

[0019] Those skilled in the art will appreciate that the information and signals described below 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 referenced throughout the following description may be represented by voltages, currents, electromagnetic waves, magnetic fields or particles, optical fields or particles, or any combination thereof, depending in part on the particular application, in part on the desired design, in part on the corresponding technology, etc.

[0020] Further, many aspects are described in terms of sequences of actions to be performed by, for example, elements of a computing device. It will be recognized that the various actions described herein may be performed by specific circuitry (e.g., an application-specific integrated circuit (ASIC)), by program instructions executed by one or more processors, or a combination of both. Additionally, the sequences of actions described herein may be considered to be embodied entirely in any form of non-transitory computer-readable storage medium storing a corresponding set of computer instructions that, when executed, cause or instruct the associated processor(s) of the device to perform the functionality described herein. Accordingly, various aspects of the present disclosure may be embodied in a number of different forms, all of which are contemplated to be within the scope of the claimed subject matter. Additionally, for each aspect described herein, the corresponding form of any such aspect may be described herein, for example, as “logic configured to” perform the described actions.

[0021] The terms “user equipment” (UE) and “base station,” as used herein, are not intended to be specific to or otherwise limited to any particular radio access technology (RAT) unless otherwise specified. In general, a UE may be any wireless communication device (e.g., a mobile phone, a router, a tablet computer, a laptop computer, a consumer asset tracking device, a wearable (e.g., a smart watch, smart glasses, an augmented reality (AR) / virtual reality (VR) headset, etc.), a vehicle (e.g., an automobile, a motorcycle, a bicycle, etc.), an Internet of Things (IoT) device, etc.) used by a user to communicate over a wireless communication network. A UE may be mobile or may be stationary (e.g., at some times) and may communicate with a radio access network (RAN). As used herein, the term “UE” may be referred to interchangeably as an “access terminal” or “AT,” a “client device,” a “wireless device,” a “subscriber device,” a “subscriber terminal,” a “subscriber station,” a “user terminal” or “UT,” a “mobile device,” a “mobile terminal,” a “mobile station,” or variations thereof. Generally, a UE can communicate with a core network via a RAN, through which the UE can be connected to external networks such as the Internet and to other UEs. Of course, other mechanisms for connecting to the core network and / or the Internet are also possible for a UE, such as via a wired access network, a wireless local area network (WLAN) network (e.g., based on the Institute of Electrical and Electronics Engineers (IEEE) 802.11 specifications, etc.), etc.

[0022] A base station may operate according to one of several RATs with which it communicates with the UE, depending on the network in which the UE is deployed, and may alternatively be referred to as an access point (AP), network node, Node B, evolved Node B (eNB), next-generation eNB (ng-eNB), New Radio (NR) Node B (also referred to as gNB or gNode B), etc. Base stations may be used primarily to support wireless access by UEs, including supporting data, voice, and / or signaling connections for supported UEs. In some systems, base stations may provide purely edge node signaling functionality, while in other systems, base stations may provide additional control and / or network management functions. A communication link through which a UE can send signals to a base station is called an uplink (UL) channel (e.g., a reverse traffic channel, a reverse control channel, an access channel, etc.). A communication link through which a base station can send signals to a UE is called a downlink (DL) channel or a forward link channel (e.g., a paging channel, a control channel, a broadcast channel, a forward traffic channel, etc.). As used herein, the term Traffic Channel (TCH) can refer to either an uplink / reverse traffic channel or a downlink / forward traffic channel.

[0023] The term "base station" can refer to a single physical transmit / receive point (TRP) or multiple physical TRPs, which may or may not be collocated. For example, when the term "base station" refers to a single physical TRP, the physical TRP may be an antenna of the base station corresponding to the base station's cell (or several cell sectors). When the term "base station" refers to multiple collocated physical TRPs, the physical TRPs may be an array of antennas of the base station (e.g., as in a multiple-input multiple-output (MIMO) system or when the base station employs beamforming). When the term "base station" refers to multiple non-collocated physical TRPs, the physical TRPs may be a distributed antenna system (DAS) (a network of spatially separated antennas connected to a common source via a transport medium) or a remote radio head (RRH) (a remote base station connected to a serving base station). Alternatively, a non-co-located physical TRP may be a serving base station that receives measurement reports from the UE and neighboring base stations whose reference radio frequency (RF) signals the UE is measuring. Because a TRP is a point from which a base station transmits and receives wireless signals, as used herein, references to transmission from or reception at a base station should be understood as references to a particular TRP of the base station.

[0024] In some implementations that support UE positioning, a base station may not support wireless access by the UE (e.g., may not support data, voice, and / or signaling connections for the UE), but instead may transmit reference signals to the UE to be measured by the UE and / or may receive and measure signals transmitted by the UE. Such a base station may be referred to as a positioning beacon (e.g., when transmitting signals to the UE) and / or a location measurement unit (e.g., when receiving and measuring signals from the UE).

[0025] An "RF signal" comprises electromagnetic waves of a given frequency that transport information through space between a transmitter and a receiver. As used herein, a transmitter may transmit a single "RF signal" or multiple "RF signals" to a receiver. However, due to the propagation characteristics of RF signals through a multipath channel, the receiver may receive multiple "RF signals" corresponding to each transmitted RF signal. The same transmitted RF signal over different paths between the transmitter and receiver is sometimes referred to as a "multipath" RF signal.

[0026] 1 illustrates an exemplary wireless communication system 100 according to an aspect of the present disclosure. The wireless communication system 100 (sometimes referred to as a wireless wide area network (WWAN)) may include various base stations 102 (labeled “BS”) and various UEs 104. The base stations 102 may include macrocell base stations (high-power cellular base stations) and / or small cell base stations (low-power cellular base stations). In one aspect, the macrocell base stations may include eNBs and / or ng-eNBs, where the wireless communication system 100 corresponds to an LTE network, or gNBs, where the wireless communication system 100 corresponds to an NR network, or a combination of both, and the small cell base stations may include femtocells, picocells, microcells, etc.

[0027] The base stations 102 may collectively form a RAN and may interface with a core network 170 (e.g., Evolved Packet Core (EPC) or 5G Core (5GC)) through backhaul links 122 and to one or more location servers 172 (e.g., a Location Management Function (LMF) or a Secure User Plane Localization (SUPL) Location Platform (SLP)) through the core network 170. The location servers 172 may be part of the core network 170 or may be external to the core network 170. In addition to other functions, the base stations 102 may perform functions related to one or more of the following: forwarding user data, radio channel encryption and decryption, integrity protection, header compression, mobility control functions (e.g., handover, dual connectivity), inter-cell interference coordination, connection setup and release, load balancing, distribution for non-access stratum (NAS) messages, NAS node selection, synchronization, RAN sharing, Multimedia Broadcast Multicast Service (MBMS), subscriber and equipment tracing, RAN Information Management (RIM), paging, positioning, and distribution of alert messages. The base stations 102 may communicate with each other directly or indirectly (e.g., through EPC / 5GC) via backhaul links 134, which may be wired or wireless.

[0028] The base stations 102 may communicate wirelessly with the UEs 104. Each of the base stations 102 may provide communication coverage for a respective geographic coverage area 110. In one aspect, one or more cells may be supported by the base stations 102 in each geographic coverage area 110. A “cell” is a logical communication entity used for communication with a base station (e.g., over some frequency resources referred to as a carrier frequency, component carrier, carrier, band, etc.) and may be associated with an identifier (e.g., a physical cell identifier (PCI), a virtual cell identifier (VCI), a cell global identifier (CGI)) to distinguish between cells operating over the same or different carrier frequencies. In some cases, different cells may be configured according to different protocol types (e.g., machine type communication (MTC), narrowband IoT (NB-IoT), enhanced mobile broadband (eMBB), or others) that may provide access to different types of UEs. Because a cell is supported by a particular base station, the term “cell” can refer to one or both of the logical communication entity and its supporting base station, depending on the context. In some cases, the term "cell" may refer to the geographic coverage area (e.g., sector) of a base station, so long as the carrier frequency can be detected and used for communication within some portion of the geographic coverage area 110.

[0029] While adjacent to macrocell base stations 102, the geographic coverage areas 110 may partially overlap (e.g., within handover regions), and some of the geographic coverage areas 110 may be significantly overlapped by larger geographic coverage areas 110. For example, a small cell (SC) base station 102' may have a geographic coverage area 110' that significantly overlaps with the geographic coverage area 110 of one or more macrocell base stations 102. A network including both small cell and macrocell base stations may be referred to as a heterogeneous network. A heterogeneous network may also include Home eNBs (HeNBs) that may serve restricted groups called closed subscriber groups (CSGs).

[0030] The communication link 120 between the base station 102 and the UE 104 may include uplink (also called reverse link) transmissions from the UE 104 to the base station 102, and / or downlink (also called forward link) transmissions from the base station 102 to the UE 104. The communication link 120 may use MIMO antenna techniques, including spatial multiplexing, beamforming, and / or transmit diversity. The communication link 120 may be over one or more carrier frequencies. The allocation of carriers may be asymmetric for the downlink and uplink (e.g., more or fewer carriers may be allocated for the downlink than for the uplink).

[0031] The wireless communication system 100 may further include a wireless local area network (WLAN) access point (AP) 150 communicating with a WLAN station (STA) 152 via a communication link 154 in an unlicensed frequency spectrum (e.g., 5 GHz). When communicating in the unlicensed frequency spectrum, the WLAN STA 152 and / or the WLAN AP 150 may perform a clear channel assessment (CCA) or listen-before-talk (LBT) procedure before communicating to determine whether a channel is available.

[0032] The small cell base station 102' may operate in a licensed and / or unlicensed frequency spectrum. When operating in an unlicensed frequency spectrum, the small cell base station 102' may employ LTE or NR technology and may use the same 5 GHz unlicensed frequency spectrum used by the WLAN AP 150. A small cell base station 102' employing LTE / 5G in an unlicensed frequency spectrum may extend coverage to and / or increase the capacity of an access network. NR in an unlicensed spectrum may be referred to as NR-U. LTE in an unlicensed spectrum may be referred to as LTE-U, licensed assisted access (LAA), or MultiFire.

[0033] The wireless communication system 100 may further include a millimeter-wave (mmW) base station 180 in communication with the UE 182 and capable of operating within mmW and / or quasi-mmW frequencies. Extremely high frequency (EHF) is the RF portion of the electromagnetic spectrum. EHF ranges from 30 GHz to 300 GHz and has wavelengths between 1 and 10 millimeters. Radio waves in this band are sometimes referred to as millimeter waves. Sub-mmW may extend down to frequencies of 3 GHz, with wavelengths of 100 millimeters. The very high frequency (SHF) band extends between 3 GHz and 30 GHz, also known as centimeter waves. Communications using the mmW / quasi-mmW radio frequency bands have high path loss and relatively short distances. The mmW base station 180 and the UE 182 may utilize beamforming (transmit and / or receive) over the mmW communication link 184 to compensate for the significant path loss and short distances. It will be appreciated that in alternative configurations, one or more base stations 102 may also transmit using mmW or quasi-mmW and beamforming. Therefore, it will be appreciated that the above illustrations are merely exemplary and should not be construed as limiting the various aspects disclosed herein.

[0034] Transmit beamforming is a technique for focusing an RF signal in a particular direction. Traditionally, when a network node (e.g., a base station) broadcasts an RF signal, it broadcasts the signal in all directions (omnidirectionally). With transmit beamforming, the network node determines where a given target device (e.g., UE) is located (relative to the transmitting network node) and projects a stronger downlink RF signal in that particular direction, thereby providing a faster and more powerful RF signal (in terms of data rate) to the receiving device. To change the directionality of the RF signal when transmitting, the network node can control the phase and relative amplitude of the RF signal at each of one or more transmitters broadcasting the RF signal. For example, the network node may use an array of antennas (called a “phased array” or “antenna array”) that creates a beam of RF waves that can be “steered” to points in different directions without actually moving the antennas. Specifically, RF currents from the transmitter are fed to individual antennas with the appropriate phase relationship so that the radio waves from the separate antennas add together to enhance radiation in desired directions while suppressing or eliminating radiation in undesired directions.

[0035] A transmit beam may be quasi-colocated, meaning that the transmit beam appears to a receiver (e.g., a UE) to have the same parameters regardless of whether the network node's own transmit antennas are physically colocated. In NR, there are four types of quasi-colocation (QCL) relationships. In particular, a given type of QCL relationship means that some parameters for a target reference RF signal on a target beam can be derived from information about a source reference RF signal on a source beam. If the source reference RF signal is QCL Type A, the receiver can use the source reference RF signal to estimate the Doppler shift, Doppler spread, mean delay, and delay spread of the target reference RF signal transmitted on the same channel. If the source reference RF signal is QCL Type B, the receiver can use the source reference RF signal to estimate the Doppler shift and Doppler spread of the target reference RF signal transmitted on the same channel. If the source reference RF signal is QCL Type C, the receiver can use the source reference RF signal to estimate the Doppler shift and mean delay of the target reference RF signal transmitted on the same channel. If the source reference RF signal is QCL Type D, the receiver can use the source reference RF signal to estimate spatial reception parameters of a target reference RF signal transmitted on the same channel.

[0036] In receive beamforming, a receiver uses receive beams to amplify RF signals detected on a given channel. For example, the receiver can increase the gain setting and / or adjust the phase setting of an antenna array in a particular direction to amplify (e.g., increase the gain level of) RF signals received from that direction. Thus, when a receiver is said to beamform in a direction, it means that the beam gain in that direction is greater than the beam gains along other directions, or that the beam gain in that direction is greatest compared to the beam gains in that direction of all other receive beams available to the receiver. This results in a stronger received signal strength (e.g., reference signal received power (RSRP), reference signal received quality (RSRQ), signal-to-interference-plus-noise ratio (SINR), etc.) of RF signals received from that direction.

[0037] The receive beams may be spatially related. Spatial relationship means that parameters for a transmit beam for a second reference signal may be derived from information about the receive beam for the first reference signal. For example, a UE may use a particular receive beam to receive one or more reference downlink reference signals (e.g., a positioning reference signal (PRS), a tracking reference signal (TRS), a phase tracking reference signal (PTRS), a cell-specific reference signal (CRS), a channel state information reference signal (CSI-RS), a primary synchronization signal (PSS), a secondary synchronization signal (SSS), a synchronization signal block (SSB), etc.) from a base station. The UE can then form a transmit beam for sending one or more uplink reference signals (e.g., an uplink positioning reference signal (UL-PRS), a sounding reference signal (SRS), a demodulation reference signal (DMRS), a PTRS, etc.) to that base station based on the parameters of the receive beam.

[0038] Note that a "downlink" beam may be either a transmit beam or a receive beam, depending on the entity that forms it. For example, if a base station forms a downlink beam to transmit a reference signal to a UE, the downlink beam is a transmit beam. However, if the UE forms a downlink beam, the downlink beam is a receive beam for receiving a downlink reference signal. Similarly, an "uplink" beam may be either a transmit beam or a receive beam, depending on the entity that forms it. For example, if a base station forms an uplink beam, the uplink beam is an uplink receive beam, and if the UE forms an uplink beam, the uplink beam is an uplink transmit beam.

[0039] In 5G, the frequency spectrum in which wireless nodes (e.g., base station 102 / 180, UE 104 / 182) operate is divided into multiple frequency ranges: FR1 (450 MHz to 6000 MHz), FR2 (24250 MHz to 52600 MHz), FR3 (above 52600 MHz), and FR4 (between FR1 and FR2). In a multi-carrier system such as 5G, one of the carrier frequencies is called the “primary carrier” or “anchor carrier” or “primary serving cell” or “PCell,” and the remaining carrier frequencies are called “secondary carriers” or “secondary serving cells” or “SCells.” In carrier aggregation, the anchor carrier is the carrier operating on the primary frequency (e.g., FR1) utilized by the UE 104 / 182 and the cell on which the UE 104 / 182 either performs an initial radio resource control (RRC) connection establishment procedure or initiates an RRC connection re-establishment procedure. The primary carrier carries all common and UE-specific control channels and may be a carrier among licensed frequencies (although this is not always the case). The secondary carrier is a carrier operating on a second frequency (e.g., FR2) that may be configured once an RRC connection is established between the UE 104 and the anchor carrier and may be used to provide additional radio resources. In some cases, the secondary carrier may be a carrier among unlicensed frequencies. Because both the primary uplink carrier and the primary downlink carrier are typically UE-specific, the secondary carrier may contain only necessary signaling information and signals; for example, UE-specific signaling information and signals may not be present in the secondary carrier. This means that different UEs 104 / 182 in a cell may have different downlink primary carriers. The same is true for the uplink primary carrier. The network can change the primary carrier of any UE 104 / 182 at any time. This is done, for example, to balance the load on different carriers.Since a "serving cell" (whether PCell or SCell) corresponds to a carrier frequency / component carrier over which several base stations are communicating, terms such as "cell," "serving cell," "component carrier," and "carrier frequency" may be used interchangeably.

[0040] For example, still referring to FIG. 1 , one of the frequencies utilized by the macrocell base station 102 may be an anchor carrier (i.e., “PCell”), and other frequencies utilized by the macrocell base station 102 and / or the mmW base station 180 may be secondary carriers (“SCells”). Simultaneous transmission and / or reception of multiple carriers allows the UE 104 / 182 to significantly increase its data transmission and / or data reception rates. For example, two aggregated 20 MHz carriers in a multi-carrier system would theoretically lead to a two-fold increase in data rate (i.e., 40 MHz) compared to that achieved with a single 20 MHz carrier.

[0041] Wireless communications system 100 may further include a UE 164, which may communicate with macrocell base station 102 via communications link 120 and / or with mmW base station 180 via mmW communications link 184. For example, macrocell base station 102 may support a PCell and one or more SCells for UE 164, and mmW base station 180 may support one or more SCells for UE 164.

[0042] In the example of FIG. 1 , one or more Earth-orbiting satellite positioning system (SPS) space vehicles (SVs) 112 (e.g., satellites) may be used as independent sources of location information for any of the illustrated UEs (shown in FIG. 1 as a single UE 104 for simplicity). The UE 104 may include one or more dedicated SPS receivers specifically designed to receive SPS signals 124 to derive geolocation information from the SVs 112. An SPS typically includes a system of transmitters (e.g., SVs 112) positioned to enable receivers (e.g., UEs 104) to determine their location on or above the Earth based, at least in part, on signals received from the transmitters (e.g., SPS signals 124). Such transmitters typically transmit signals marked with a repeating pseudorandom noise (PN) code of a set number of chips. While typically located within the SVs 112, transmitters may sometimes be located on ground-based control stations, base stations 102, and / or other UEs 104.

[0043] Use of SPS signals 124 may be augmented by various satellite-based augmentation systems (SBAS) that may be associated with or otherwise enabled for use with one or more global and / or regional navigation satellite systems. For example, SBAS may include augmentation systems that provide integrity information, differential corrections, and the like, such as the Wide Area Augmentation System (WAAS), the European Geostationary Navigation Overlay Service (EGNOS), the Multifunction Satellite Augmentation System (MSAS), the Global Positioning System (GPS)-Aided Geo-Augmented Navigation, or the GPS and Geo-Augmented Navigation System (GAGAN). Thus, as used herein, SPS may include any combination of one or more global and / or regional navigation satellite systems and / or augmentation systems, and SPS signals 124 may include SPS, SPS-like signals, and / or other signals associated with such one or more SPSs.

[0044] The wireless communication system 100 may further include one or more UEs, such as a UE 190, that indirectly connect to one or more communication networks via one or more device-to-device (D2D) peer-to-peer (P2P) links (referred to as “sidelinks”). In the example of FIG. 1, the UE 190 has a D2D P2P link 192 with one of the UEs 104 connected to one of the base stations 102 (e.g., through which the UE 190 may indirectly obtain cellular connectivity), and a D2D P2P link 194 with a WLAN STA 152 connected to a WLAN AP 150 (through which the UE 190 may indirectly obtain WLAN-based Internet connectivity). In one example, the D2D P2P links 192 and 194 may be supported using any well-known D2D RAT, such as LTE Direct (LTE-D), WiFi Direct (WiFi-D), Bluetooth®, etc.

[0045] 2A shows an exemplary wireless network structure 200. For example, a 5GC 210 (also referred to as a Next Generation Core (NGC)) can be viewed functionally as a control plane function 214 (e.g., UE registration, authentication, network access, gateway selection, etc.) and a user plane function 212 (e.g., UE gateway function, access to data network, IP routing, etc.), which operate cooperatively to form a core network. A user plane interface (NG-U) 213 and a control plane interface (NG-C) 215 connect a gNB 222 to the 5GC 210, specifically to the control plane function 214 and the user plane function 212. In an additional configuration, an ng-eNB 224 may also be connected to the 5GC 210 via the NG-C 215 to the control plane function 214 and the NG-U 213 to the user plane function 212. Additionally, the ng-eNB 224 may communicate directly with the gNB 222 via a backhaul connection 223. In some configurations, the Next Generation RAN (NG-RAN) 220 may have only one or more gNBs 222, while other configurations include one or more of both an ng-eNB 224 and a gNB 222. Either the gNB 222 or the ng-eNB 224 may be in communication with the UE 204 (e.g., any of the UEs shown in FIG. 1). Another optional aspect may include a location server 230, which may be in communication with the 5GC 210 to provide location assistance to the UE 204. The location servers 230 may be implemented as multiple separate servers (e.g., physically separate servers, different software modules on a single server, different software modules spread across multiple physical servers, etc.), or alternatively, each may correspond to a single server. The location server 230 may be configured to support one or more location services for UEs 204 that can connect to the location server 230 via the core network 5GC 210 and / or via the Internet (not shown). Furthermore, the location server 230 may be integrated into a component of the core network, or alternatively, may be external to the core network.

[0046] 2B shows another exemplary wireless network structure 250. The 5GC 260 (which may correspond to the 5GC 210 in FIG. 2A ) may be viewed functionally as a control plane function provided by an access and mobility management function (AMF) 264 and a user plane function provided by a user plane function (UPF) 262, which operate cooperatively to form a core network (i.e., the 5GC 260). A user plane interface 263 and a control plane interface 265 connect the ng-eNB 224 to the 5GC 260, specifically to the UPF 262 and the AMF 264, respectively. In an additional configuration, the gNB 222 may also be connected to the 5GC 260 via the control plane interface 265 to the AMF 264 and the user plane interface 263 to the UPF 262. Furthermore, the ng-eNB 224 may communicate directly with the gNB 222 via the backhaul connection 223, with or without gNB direct connectivity to the 5GC 260. In some configurations, the NG-RAN 220 may have only one or more gNBs 222, while other configurations include one or more of both an ng-eNB 224 and a gNB 222. Either the gNB 222 or the ng-eNB 224 may communicate with the UE 204 (e.g., any of the UEs shown in FIG. 1). The base stations of the NG-RAN 220 communicate with the AMF 264 over an N2 interface and with the UPF 262 over an N3 interface.

[0047] The AMF 264 functions include registration management, connection management, reachability management, mobility management, lawful intercept, transport for session management (SM) messages between the UE 204 and a session management function (SMF) 266, a transparent proxy service for routing SM messages, access authentication and access authorization, transport for short message service (SMS) messages between the UE 204 and a short message service function (SMSF) (not shown), and a security anchor functionality (SEAF). The AMF 264 also interacts with an authentication server function (AUSF) (not shown) and the UE 204 to receive intermediate keys established as a result of the UE 204 authentication process. In the case of UMTS (Universal Mobile Telecommunications System) subscriber identity module (USIM)-based authentication, the AMF 264 retrieves security material from the AUSF. The AMF 264 functions also include security context management (SCM). The SCM receives keys from the SEAF that the SCM uses to derive access network-specific keys. The functionality of the AMF 264 also includes location service management for regulatory services, transport for location service messages between the UE 204 and the LMF 270 (acting as the location server 230), transport for location service messages between the NG-RAN 220 and the LMF 270, Evolved Packet System (EPS) bearer identifier allocation for interworking with EPS, and UE 204 mobility event notification. In addition, the AMF 264 also supports functionality for non-3GPP (Third Generation Partnership Project) access networks.

[0048] The functions of the UPF 262 include acting as an anchor point for intra- / inter-RAT mobility (when applicable), acting as an outer protocol data unit (PDU) session point for interconnection to a data network (not shown), routing and forwarding packets, packet inspection, user plane policy rule enforcement (e.g., gating, redirection, traffic steering), lawful interception (user plane collection), traffic usage reporting, quality of service (QoS) processing for the user plane (e.g., uplink / downlink rate enforcement, reflective QoS marking in the downlink), uplink traffic validation (service data flow (SDF) to QoS flow mapping), transport-level packet marking in the uplink and downlink, downlink packet buffering and downlink data notification triggering, and sending and forwarding one or more "end markers" to the source RAN node. The UPF 262 may also support the transfer of location service messages over the user plane between the UE 204 and a location server such as the SLP 272.

[0049] The functions of the SMF 266 include session management, UE Internet Protocol (IP) address allocation and management, selection and control of user plane functions, configuration of traffic steering in the UPF 262 to route traffic to the appropriate destination, control of policy enforcement and part of QoS, and downlink data notification. The interface through which the SMF 266 communicates with the AMF 264 is called the N11 interface.

[0050] Another optional aspect may include an LMF 270, which may be in communication with the 5GC 260 to provide location assistance to the UE 204. The LMF 270 may be implemented as multiple separate servers (e.g., physically separate servers, different software modules on a single server, different software modules spread across multiple physical servers, etc.), or alternatively, each may correspond to a single server. The LMF 270 may be configured to support one or more location services for UEs 204 that can connect to the LMF 270 via the core network 5GC 260 and / or via the Internet (not shown). The SLP 272 may support similar functions as the LMF 270, while the LMF 270 may communicate with the AMF 264, the NG-RAN 220, and the UE 204 via the control plane (e.g., using interfaces and protocols intended to convey signaling messages rather than voice or data), and the SLP 272 may communicate with the UE 204 and external clients (not shown in FIG. 2B) via the user plane (e.g., using protocols intended to carry voice and / or data, such as Transmission Control Protocol (TCP) and / or IP).

[0051] 3A, 3B, and 3C illustrate several example components (represented by corresponding blocks) that may be incorporated within a UE 302 (which may correspond to any of the UEs described herein), a base station 304 (which may correspond to any of the base stations described herein), and a network entity 306 (which may correspond to or embody any of the network functions described herein, including location server 230 and LMF 270) to support file transmission operations as taught herein. It will be appreciated that these components may be implemented in different types of devices in different implementations (e.g., in an ASIC, in a system-on-chip (SoC), etc.). The illustrated components may also be incorporated into other devices in a communication system. For example, other devices in the system may include components similar to the illustrated components to provide similar functionality. Also, a given device may include one or more of the components. For example, a device may include multiple transceiver components that enable the device to operate on multiple carriers and / or communicate via different technologies.

[0052] The UE 302 and base station 304 each include a wireless wide area network (WWAN) transceiver 310 and 350, respectively, that provides means for communicating (e.g., means for transmitting, means for receiving, means for measuring, means for tuning, means for refraining from transmitting, etc.) over one or more wireless communications networks (not shown), such as an NR network, an LTE network, a GSM network, etc. The WWAN transceivers 310 and 350 may be connected to one or more antennas 316 and 356, respectively, for communicating with other network nodes, such as other UEs, access points, base stations (e.g., eNBs, gNBs), etc., via at least one designated RAT (e.g., NR, LTE, GSM, etc.) over a wireless communications medium of interest (e.g., some set of time / frequency resources within a particular frequency spectrum). The WWAN transceivers 310 and 350 may be variously configured to transmit and encode signals 318 and 358 (e.g., messages, indications, information, etc.), respectively, and conversely, to receive and decode signals 318 and 358 (e.g., messages, indications, information, pilots, etc.), respectively, in accordance with a designated RAT. In particular, the WWAN transceivers 310 and 350 include one or more transmitters 314 and 354, respectively, for transmitting and encoding signals 318 and 358, respectively, and one or more receivers 312 and 352, respectively, for receiving and decoding signals 318 and 358, respectively.

[0053] The UE 302 and base station 304 also, at least in some cases, include one or more short-range wireless transceivers 320 and 360, respectively. The short-range wireless transceivers 320 and 360 may be connected to one or more antennas 326 and 366, respectively, and may provide means for communicating (e.g., means for transmitting, means for receiving, means for measuring, means for tuning, means for refraining from transmitting, etc.) with other network nodes, such as other UEs, access points, base stations, etc., via at least one designated RAT (e.g., WiFi, LTE-D, Bluetooth, Zigbee, Z-Wave, PC5, dedicated short-range communications (DSRC), wireless access for vehicular environments (WAVE), near field communications (NFC), etc.) over a target wireless communications medium. The short-range wireless transceivers 320 and 360 may be variously configured to transmit and encode signals 328 and 368 (e.g., messages, indications, information, etc.), respectively, and conversely, to receive and decode signals 328 and 368 (e.g., messages, indications, information, pilots, etc.), respectively, in accordance with a designated RAT. In particular, the short-range wireless transceivers 320 and 360 include one or more transmitters 324 and 364, respectively, to transmit and encode signals 328 and 368, respectively, and one or more receivers 322 and 362, respectively, to receive and decode signals 328 and 368, respectively. As specific examples, the short-range wireless transceivers 320 and 360 may be WiFi transceivers, Bluetooth® transceivers, Zigbee® and / or Z-Wave® transceivers, NFC transceivers, or vehicle-to-vehicle (V2V) and / or vehicle-to-everything (V2X) transceivers.

[0054] Transceiver circuitry including at least one transmitter and at least one receiver may in some implementations comprise an integrated device (e.g., embodied as transmitter and receiver circuitry in a single communications device), in some implementations comprise separate transmitter and receiver devices, or in other implementations may be embodied in other ways. In one aspect, a transmitter may include or be coupled to multiple antennas (e.g., antennas 316, 326, 356, 366), such as an antenna array that enables each device to perform transmit “beamforming” as described herein. Similarly, a receiver may include or be coupled to multiple antennas (e.g., antennas 316, 326, 356, 366), such as an antenna array that enables each device to perform receive beamforming as described herein. In one aspect, transmitters and receivers may share multiple identical antennas (e.g., antennas 316, 326, 356, 366), such that each device can only receive or transmit at a given time, but not both at the same time. The wireless communication device of the UE 302 and / or base station 304 (e.g., one or both of the transceivers 310 and 320 and / or 350 and 360) may also include a network listen module (NLM) or the like for performing various measurements.

[0055] The UE 302 and base station 304 also, at least in some cases, include satellite positioning system (SPS) receivers 330 and 370. The SPS receivers 330 and 370 may be connected to one or more antennas 336 and 376, respectively, and may provide a means for receiving and / or measuring SPS signals 338 and 378, respectively, such as Global Positioning System (GPS) signals, Global Navigation Satellite System (GLONASS) signals, Galileo signals, Beidou signals, Navigation Satellite System of India (NAVIC), Quasi-Zenith Satellite System (QZSS), etc. The SPS receivers 330 and 370 may comprise any suitable hardware and / or software for receiving and processing the SPS signals 338 and 378, respectively. The SPS receivers 330 and 370 request information and actions from other systems as appropriate and perform the necessary calculations to determine the position of the UE 302 and base station 304 using the obtained measurements, via any suitable SPS algorithms.

[0056] The base station 304 and the network entity 306 each include at least one network interface 380 and 390, respectively, that provide means for communicating (e.g., means for transmitting, means for receiving, etc.) with other network entities. For example, the network interfaces 380 and 390 (e.g., one or more network access ports) may be configured to communicate with one or more network entities via a wire-based or wireless backhaul connection. In some aspects, the network interfaces 380 and 390 may be implemented as transceivers configured to support wire-based or wireless signal communication. This communication may involve, for example, sending and receiving messages, parameters, and / or other types of information.

[0057] The UE 302, base station 304, and network entity 306 also include other components that may be used in conjunction with operations as disclosed herein. The UE 302 includes processor circuitry implementing a processing system 332, e.g., for providing functionality related to wireless positioning and for providing other processing functionality. The base station 304 includes a processing system 384, e.g., for providing functionality related to wireless positioning and for providing other processing functionality. The network entity 306 includes a processing system 394, e.g., for providing functionality related to wireless positioning and for providing other processing functionality. Thus, the processing systems 332, 384, and 394 may provide means for processing, such as means for determining, means for calculating, means for receiving, means for transmitting, means for indicating, etc. In one aspect, processing systems 332, 384, and 394 may include one or more processors, such as, for example, one or more general-purpose processors, multi-core processors, ASICs, digital signal processors (DSPs), field programmable gate arrays (FPGAs), other programmable logic devices or processing circuitry, or various combinations thereof.

[0058] The UE 302, the base station 304, and the network entity 306 include memory circuitry implementing memory components 340, 386, and 396, respectively (e.g., each including a memory device) for maintaining information (e.g., information indicative of reserved resources, thresholds, parameters, etc.). Thus, the memory components 340, 386, and 396 may provide means for storing, means for retrieving, means for retaining, etc. In some cases, the UE 302, the base station 304, and the network entity 306 may include RIS modules 342, 388, and 398, respectively. The RIS modules 342, 388, and 398 may be hardware circuits that are part of or coupled to the processing systems 332, 384, and 394, respectively, that, when executed, cause the UE 302, the base station 304, and the network entity 306 to perform the functionality described herein. In other aspects, RIS modules 342, 388, and 398 may be external to processing systems 332, 384, and 394 (e.g., may be part of a modem processing system, may be integrated with another processing system, etc.). Alternatively, RIS modules 342, 388, and 398 may be memory modules stored in memory components 340, 386, and 396, respectively, that, when executed by processing systems 332, 384, and 394 (or modem processing system, another processing system, etc.), cause UE 302, base station 304, and network entity 306 to perform the functionality described herein. FIG. 3A shows possible locations for RIS module 342, which may be part of WWAN transceiver 310, memory component 340, processing system 332, or any combination thereof, or may be a stand-alone component. FIG. 3B illustrates possible locations for a RIS module 388, which may be part of the WWAN transceiver 350, memory component 386, processing system 384, or any combination thereof, or may be a stand-alone component.FIG. 3C illustrates possible locations for a RIS module 398, which may be part of the network interface 390, memory component 396, processing system 394, or any combination thereof, or may be a stand-alone component.

[0059] The UE 302 may include one or more sensors 344 coupled to the processing system 332 to provide a means for sensing or detecting motion and / or orientation information that is independent of motion data derived from signals received by the WWAN transceiver 310, the short-range wireless transceiver 320, and / or the SPS receiver 330. By way of example, the sensors 344 may include an accelerometer (e.g., a microelectromechanical system (MEMS) device), a gyroscope, a geomagnetic sensor (e.g., a compass), an altimeter (e.g., a barometric altimeter), and / or any other type of motion detection sensor. Moreover, the sensors 344 may include multiple different types of devices and combine their outputs to provide motion information. For example, the sensors 344 may use a combination of a multi-axis accelerometer and an orientation sensor to provide the ability to calculate a position in a 2D and / or 3D coordinate system.

[0060] Additionally, the UE 302 includes a user interface 346 that provides a means for providing an indication to a user (e.g., an audio and / or visual indication) and / or receiving user input (e.g., upon user actuation of a sensing device such as a keypad, touch screen, microphone, etc.). Although not shown, the base station 304 and the network entity 306 may also include user interfaces.

[0061] Referring more particularly to the processing system 384, on the downlink, IP packets from the network entity 306 may be provided to the processing system 384. The processing system 384 may implement functionality for an RRC layer, a Packet Data Convergence Protocol (PDCP) layer, a Radio Link Control (RLC) layer, and a Medium Access Control (MAC) layer. The processing system 384 may provide RRC layer functionality related to broadcasting of system information (e.g., Master Information Block (MIB), System Information Block (SIB)), RRC connection control (e.g., RRC connection paging, RRC connection establishment, RRC connection modification, and RRC connection release), inter-RAT mobility, and measurement configuration for UE measurement reporting; PDCP layer functionality related to header compression / decompression, security (encryption, decryption, integrity protection, integrity verification), and handover support functions; RLC layer functionality related to transfer of upper layer PDUs, error correction through automatic repeat request (ARQ), concatenation, segmentation, and reassembly of RLC service data units (SDUs), resegmentation of RLC data PDUs, and reordering of RLC data PDUs; and MAC layer functionality related to mapping between logical channels and transport channels, scheduling information reporting, error correction, priority handling, and logical channel prioritization.

[0062] The transmitter 354 and receiver 352 may implement Layer 1 (L1) functionality related to various signal processing functions. Layer 1, which includes the physical (PHY) layer, may include error detection on transport channels, forward error correction (FEC) coding / decoding of transport channels, interleaving, rate matching, mapping onto physical channels, modulation / demodulation of physical channels, and MIMO antenna processing. The transmitter 354 handles mapping to signal constellations based on various modulation schemes (e.g., binary phase shift keying (BPSK), quadrature phase shift keying (QPSK), M-phase shift keying (M-PSK), M-ary quadrature amplitude modulation (M-QAM)). The coded and modulated symbols may then be split into parallel streams. Each stream may then be mapped to an orthogonal frequency division multiplexing (OFDM) subcarrier, multiplexed with a reference signal (e.g., a pilot) in the time and / or frequency domain, and then combined together using an inverse fast Fourier transform (IFFT) to generate a physical channel carrying a time-domain OFDM symbol stream. The OFDM symbol stream is spatially precoded to generate multiple spatial streams. Channel estimates from a channel estimator may be used to determine coding and modulation schemes and for spatial processing. The channel estimates may be derived from a reference signal and / or channel condition feedback transmitted by the UE 302. Each spatial stream may then be provided to one or more different antennas 356. The transmitter 354 may modulate an RF carrier with the respective spatial stream for transmission.

[0063] At the UE 302, the receiver 312 receives signals through its respective antenna 316. The receiver 312 recovers the information modulated onto the RF carriers and provides the information to the processing system 332. The transmitter 314 and receiver 312 perform Layer 1 functionality related to various signal processing functions. The receiver 312 may perform spatial processing on the information to recover any spatial streams destined for the UE 302. If multiple spatial streams are destined for the UE 302, they may be combined into a single OFDM symbol stream by the receiver 312. The receiver 312 then converts the OFDM symbol stream from the time domain to the frequency domain using a fast Fourier transform (FFT). The frequency domain signal comprises a separate OFDM symbol stream for each subcarrier of the OFDM signal. The symbols on each subcarrier, as well as the reference signal, are recovered and demodulated by determining the signal constellation point that was most likely transmitted by the base station 304. These soft decisions may be based on channel estimates calculated by a channel estimator. The soft decisions are then decoded and deinterleaved to recover the data and control signals originally transmitted on the physical channel by the base station 304. The data and control signals are then provided to a processing system 332 that performs Layer 3 (L3) and Layer 2 (L2) functionality.

[0064] In the uplink, the processing system 332 performs demultiplexing between transport and logical channels, packet reassembly, decryption, header decompression, and control signal processing to recover IP packets from the core network. The processing system 332 is also responsible for error detection.

[0065] Similar to the functionality described with respect to downlink transmissions by the base station 304, the processing system 332 provides RRC layer functionality related to system information (e.g., MIB, SIB) acquisition, RRC connection, and measurement reporting; PDCP layer functionality related to header compression / decompression and security (encryption, decryption, integrity protection, integrity verification); RLC layer functionality related to transfer of upper layer PDUs, error correction via ARQ, concatenation, segmentation, and reassembly of RLC SDUs, resegmentation of RLC data PDUs, and reordering of RLC data PDUs; and MAC layer functionality related to mapping between logical channels and transport channels, multiplexing of MAC SDUs onto transport blocks (TBs), demultiplexing of MAC SDUs from TBs, scheduling information reporting, error correction via hybrid automatic repeat request (HARQ), priority handling, and logical channel prioritization.

[0066] Channel estimates derived by the channel estimator from a reference signal or feedback transmitted by the base station 304 may be used by the transmitter 314 to select an appropriate coding and modulation scheme and to facilitate spatial processing. The spatial streams generated by the transmitter 314 may be provided to different antennas 316. The transmitter 314 may modulate an RF carrier with each spatial stream for transmission.

[0067] Uplink transmissions are processed at the base station 304 in a manner similar to that described with respect to the receiver function at the UE 302. The receiver 352 receives the signal through its respective antenna 356. The receiver 352 recovers the information modulated onto the RF carrier and provides the information to the processing system 384.

[0068] In the uplink, the processing system 384 performs demultiplexing between transport and logical channels, packet reassembly, decryption, header decompression, and control signal processing to recover IP packets from the UE 302. The IP packets from the processing system 384 may be provided to the core network. The processing system 384 is also responsible for error detection.

[0069] For convenience, the UE 302, the base station 304, and / or the network entity 306 are illustrated in Figures 3A-3C as including various components that may be configured in accordance with various examples described herein. However, it will be appreciated that the illustrated blocks may have different functionality in different designs.

[0070] The various components of the UE 302, the base station 304, and the network entity 306 may communicate with each other via data buses 334, 382, ​​and 392, respectively. The components of FIGS. 3A-3C may be implemented in various ways. In some implementations, the components of FIGS. 3A-3C may be implemented in one or more circuits, such as, for example, one or more processors and / or one or more ASICs (which may include one or more processors), where each circuit may use and / or incorporate at least one memory component for storing information or executable code used by the circuit to provide its functionality. For example, some or all of the functionality represented by blocks 310-346 may be performed by the processor and memory components of the UE 302 (e.g., by execution of appropriate code and / or by appropriate configuration of the processor components). Similarly, some or all of the functionality represented by blocks 350-388 may be performed by the processor and memory components of the base station 304 (e.g., by execution of appropriate code and / or by appropriate configuration of the processor components). Additionally, some or all of the functionality represented by blocks 390-398 may be implemented by the processor and memory components of the network entity 306 (e.g., by execution of appropriate code and / or by appropriate configuration of the processor components). For simplicity, various operations, acts, and / or functions are described herein as being performed "by the UE," "by the base station," "by the network entity," etc. However, it will be appreciated that such operations, acts, and / or functions may actually be performed by particular components or combinations of components of the UE 302, base station 304, network entity 306, etc., such as processing systems 332, 384, 394, transceivers 310, 320, 350, and 360, memory components 340, 386, and 396, RIS modules 342, 388, and 398, etc.

[0071] Various frame structures may be used to support downlink and uplink transmissions between network nodes (e.g., base stations and UEs). Figure 4A is a diagram 400 illustrating an example of a downlink frame structure according to an embodiment of the present disclosure. Figure 4B is a diagram 430 illustrating an example of channels within a downlink frame structure according to an embodiment of the present disclosure. Figure 4C is a diagram 450 illustrating an example of an uplink frame structure according to an embodiment of the present disclosure. Figure 4D is a diagram 480 illustrating an example of channels within an uplink frame structure according to an embodiment of the present disclosure. Other wireless communication technologies may have different frame structures and / or different channels.

[0072] LTE, and possibly NR, utilizes OFDM on the downlink and single-carrier frequency division multiplexing (SC-FDM) on the uplink. However, unlike LTE, NR has the option to also use OFDM on the uplink. OFDM and SC-FDM partition the system bandwidth into multiple (K) orthogonal subcarriers, also commonly referred to as tones, bins, etc. Each subcarrier may be modulated with data. Generally, modulation symbols are sent in the frequency domain with OFDM and in the time domain with SC-FDM. The spacing between adjacent subcarriers may be fixed, and the total number of subcarriers (K) may depend on the system bandwidth. For example, the subcarrier spacing may be 15 kilohertz (kHz), and the minimum resource allocation (resource block) may be 12 subcarriers (i.e., 180 kHz). Thus, the nominal FFT size may be equal to 128, 256, 512, 1024, or 2048 for a system bandwidth of 1.25, 2.5, 5, 10, or 20 megahertz (MHz), respectively. The system bandwidth may also be partitioned into subbands. For example, a subband may cover 1.08 MHz (i.e., 6 resource blocks), and there may be 1, 2, 4, 8, or 16 subbands for a system bandwidth of 1.25, 2.5, 5, 10, or 20 MHz, respectively.

[0073] LTE supports a single numerology (subcarrier spacing (SCS), symbol length, etc.). In contrast, NR may support multiple numerologies (μ), e.g., subcarrier spacings of 15 kHz (μ=0), 30 kHz (μ=1), 60 kHz (μ=2), 120 kHz (μ=3), and 240 kHz (μ=4) or greater may be available. At each subcarrier spacing, there are 14 symbols per slot. For a 15 kHz SCS (μ=0), there is one slot per subframe, i.e., 10 slots per frame, with a slot duration of 1 millisecond (ms), a symbol duration of 66.7 microseconds (μs), and a maximum nominal system bandwidth (in MHz) of 50 with an FFT size of 4K. For a 30 kHz SCS (μ=1), there are two slots per subframe, i.e., 20 slots per frame, with a slot duration of 0.5 ms, a symbol duration of 33.3 μs, and a maximum nominal system bandwidth (in MHz) of 100 for a 4K FFT size. For a 60 kHz SCS (μ=2), there are four slots per subframe, i.e., 40 slots per frame, with a slot duration of 0.25 ms, a symbol duration of 16.7 μs, and a maximum nominal system bandwidth (in MHz) of 200 for a 4K FFT size. For a 120 kHz SCS (μ=3), there are eight slots per subframe, i.e., 80 slots per frame, with a slot duration of 0.125 ms, a symbol duration of 8.33 μs, and a maximum nominal system bandwidth (in MHz) of 400 for a 4K FFT size. For a 240 kHz SCS (μ=4), there are 16 slots per subframe, i.e., 160 slots per frame, the slot duration is 0.0625 ms, the symbol duration is 4.17 μs, and the maximum nominal system bandwidth (in MHz) with an FFT size of 4K is 800.

[0074] In the example of Figures 4A-4D, a 15 kHz numerology is used. Thus, in the time domain, a 10 ms frame is divided into 10 equal-sized subframes of 1 ms each, with each subframe containing one time slot. In Figures 4A-4D, time is represented horizontally (on the x-axis) with time increasing from left to right, and frequency is represented vertically (on the y-axis) with frequency increasing (or decreasing) from bottom to top.

[0075] A resource grid may be used to represent a time slot, and each time slot includes one or more time-parallel resource blocks (RBs) (also called physical RBs (PRBs)) in the frequency domain. The resource grid is further divided into multiple resource elements (REs). An RE may correspond to one symbol length in the time domain and one subcarrier in the frequency domain. In the numerology of FIGS. 4A-4D, for a normal cyclic prefix, an RB may include 12 consecutive subcarriers in the frequency domain and 7 consecutive symbols in the time domain to obtain a total of 84 REs. For an extended cyclic prefix, an RB may include 12 consecutive subcarriers in the frequency domain and 6 consecutive symbols in the time domain to obtain a total of 72 REs. The number of bits carried by each RE depends on the modulation scheme.

[0076] Some of the REs carry downlink reference (pilot) signals (DL-RS), which may include PRS, TRS, PTRS, CRS, CSI-RS, DMRS, PSS, SSS, SSB, etc. Figure 4A shows example locations of REs (labeled "R") carrying PRS.

[0077] A set of resource elements (REs) used for transmitting a PRS is called a "PRS resource." A set of resource elements can span multiple PRBs in the frequency domain and "N" (e.g., one or more) consecutive symbols within a slot in the time domain. Within a given OFDM symbol in the time domain, PRS resources occupy consecutive PRBs in the frequency domain.

[0078] The transmission of PRS resources within a given PRB has a particular comb size (also called "comb density"). The comb size "N" represents the subcarrier spacing (or frequency / tone spacing) within each symbol of the PRS resource configuration. Specifically, for comb size "N," a PRS is transmitted in every Nth subcarrier of a symbol of the PRB. For example, for comb 4, for each symbol of the PRS resource configuration, REs corresponding to every fourth subcarrier (subcarriers 0, 4, 8, etc.) are used to transmit the PRS of the PRS resource. Currently, the following comb sizes are supported for DL-PRS: comb 2, comb 4, comb 6, and comb 12. Figure 4A shows an example PRS resource configuration for comb 6 (spanning six symbols). That is, the location of the shaded REs (labeled "R") indicates the comb 6 PRS resource configuration.

[0079] Currently, DL-PRS resources can span 2, 4, 6, or 12 consecutive symbols within a slot with a staggered pattern across the frequency domain. DL-PRS resources can be configured within any higher layer configured downlink or flexible (FL) symbols of a slot. There can be a constant energy per resource element (EPRE) for all REs of a given DL-PRS resource. Below are the symbol-to-symbol frequency offsets for comb sizes 2, 4, 6, and 12 across 2, 4, 6, and 12 symbols: 2-symbol-comb2: {0, 1}, 4-symbol-comb2: {0, 1, 0, 1}, 6-symbol-comb2: {0, 1, 0, 1, 0, 1}, 12-symbol-comb2: {0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1}, 4-symbol-comb4: {0, 2, 1, 3}, 12-symbol-comb4: {0, 2, 1, 3, 0, 2, 1, 3, 0, 2, 1, 3}, 6-symbol-comb6: {0, 3, 1, 4, 2, 5}, 12-symbol-comb6: {0, 3, 1, 4, 2, 5, 0, 3, 1, 4, 2, 5}, and 12-symbol-comb12: {0, 6, 3, 9, 1, 7, 4,10, 2, 8, 5,11}.

[0080] A "PRS resource set" is a set of PRS resources used for transmitting PRS signals, where each PRS resource has a PRS resource ID. In addition, PRS resources within a PRS resource set are associated with the same TRP. A PRS resource set is identified by a PRS resource set ID and associated with a specific TRP (identified by a TRP ID). In addition, PRS resources within a PRS resource set have the same periodicity across slots, a common muting pattern configuration, and the same repetition factor (e.g., "PRS-ResourceRepetitionFactor"). Periodicity is the time from the first repetition of the first PRS resource of the first PRS instance to the same first repetition of the same first PRS resource of the next PRS instance. The periodicity may have a length selected from 2^μ*{4, 5, 8, 10, 16, 20, 32, 40, 64, 80, 160, 320, 640, 1280, 2560, 5120, 10240} slots with μ=0, 1, 2, 3. The repetition factor may have a length selected from {1, 2, 4, 6, 8, 16, 32} slots.

[0081] A PRS resource ID in a PRS resource set is associated with a single beam (or beam ID) transmitted from a single TRP (where a TRP may transmit one or more beams). That is, each PRS resource in a PRS resource set may be transmitted on a different beam, and thus a "PRS resource" or simply a "resource" may also be referred to as a "beam." Note that this does not have any implications as to whether the TRP and the beam on which the PRS is transmitted are known to the UE.

[0082] A "PRS instance" or "PRS occasion" is one instance of a periodically repeating time window (e.g., a group of one or more contiguous slots) during which a PRS is expected to be transmitted. A PRS occasion may also be referred to as a "PRS positioning occasion," "PRS positioning instance," "positioning occasion," "positioning instance," "positioning repetition," or simply an "occasion," "instance," or "repetition."

[0083] A "positioning frequency layer" (also simply referred to as a "frequency layer") is a collection of one or more PRS resource sets across one or more TRPs with the same values ​​for several parameters. In particular, the collection of PRS resource sets has the same subcarrier spacing and cyclic prefix (CP) type (meaning that all numerologies supported for PDSCH are also supported for PRS), the same Point A, the same value of downlink PRS bandwidth, the same starting PRB (and center frequency), and the same comb size. The Point A parameter takes the value of the parameter "ARFCN-ValueNR" (where "ARFCN" stands for "absolute radio frequency channel number"), which is an identifier / code that specifies a pair of physical radio channels used for transmission and reception. The downlink PRS bandwidth may have a granularity of four PRBs, with a minimum of 24 PRBs and a maximum of 272 PRBs. Currently, up to four frequency layers are defined, and up to two PRS resource sets per TRP per frequency layer can be configured.

[0084] The concept of a frequency layer is somewhat similar to that of a component carrier and bandwidth portion (BWP), but differs in that a component carrier and BWP are used by one base station (or a macrocell base station and a small cell base station) to transmit a data channel, while a frequency layer is used by several (usually three or more) base stations to transmit a PRS. A UE may indicate the number of frequency layers it can support when it sends its positioning capabilities to the network, such as during an LTE Positioning Protocol (LPP) session. For example, the UE may indicate whether it can support one positioning frequency layer or four positioning frequency layers.

[0085] Figure 4B shows an example of various channels within a downlink slot of a radio frame. In NR, the channel bandwidth or system bandwidth is divided into multiple BWPs. A BWP is a contiguous set of PRBs selected from a contiguous subset of common RBs for a given numerology on a given carrier. Generally, up to four BWPs can be specified in the downlink and uplink. That is, a UE can be configured with up to four BWPs on the downlink and up to four BWPs on the uplink. Only one BWP (uplink or downlink) can be active at a given time, meaning that a UE can only receive or transmit via one BWP at a time. On the downlink, the bandwidth of each BWP should be equal to or greater than the bandwidth of an SSB, but each BWP may or may not include an SSB.

[0086] Referring to FIG. 4B, a primary synchronization signal (PSS) is used by a UE to determine subframe / symbol timing and physical layer identity. A secondary synchronization signal (SSS) is used by a UE to determine a physical layer cell identity group number and radio frame timing. Based on the physical layer identity and the physical layer cell identity group number, the UE can determine the PCI. Based on the PCI, the UE can determine the location of the DL-RS mentioned above. A physical broadcast channel (PBCH) carrying an MIB may be logically grouped with the PSS and SSS to form an SSB (also referred to as SS / PBCH). The MIB provides the number of RBs in the downlink system bandwidth and the system frame number (SFN). A physical downlink shared channel (PDSCH) carries user data, broadcast system information not transmitted over the PBCH, such as system information blocks (SIBs), and paging messages.

[0087] The physical downlink control channel (PDCCH) carries downlink control information (DCI) in one or more control channel elements (CCEs), each of which contains one or more RE group (REG) bundles (which may span multiple symbols in the time domain). Each REG bundle contains one or more REGs, and each REG corresponds to 12 resource elements (one resource block) in the frequency domain and one OFDM symbol in the time domain. The set of physical resources used to carry the PDCCH / DCI is called a control resource set (core set (CORESET)) in NR. In NR, the PDCCH is confined to a single core set and transmitted with its own DMRS. This enables UE-specific beamforming for the PDCCH.

[0088] In the example of Figure 4B, there is one core set per BWP, and the core set spans three symbols in the time domain (although it could be only one or two symbols). Unlike LTE control channels, which occupy the entire system bandwidth, in NR, the PDCCH channel is localized to a specific region (i.e., a core set) in the frequency domain. Therefore, the frequency components of the PDCCH shown in Figure 4B are illustrated as being smaller than a single BWP in the frequency domain. Note that while the illustrated core sets are contiguous in the frequency domain, this is not required. Additionally, the core sets may span less than three symbols in the time domain.

[0089] The DCI in the PDCCH carries information about uplink resource allocations (persistent and non-persistent), called uplink grants and downlink grants, respectively, and a description of the downlink data to be transmitted to the UE. More specifically, the DCI indicates the resources scheduled for the downlink data channel (e.g., PDSCH) and the uplink data channel (e.g., PUSCH). Multiple (e.g., up to eight) DCIs may be configured in the PDCCH, and these DCIs may have one of multiple formats. For example, there are various DCI formats for uplink scheduling, for downlink scheduling, for uplink transmit power control (TPC), etc. The PDCCH may be transported by 1, 2, 4, 8, or 16 CCEs to accommodate different DCI payload sizes or coding rates.

[0090] As shown in FIG. 4C , some of the REs (labeled “R”) carry DMRS for channel estimation at a receiver (e.g., a base station, another UE, etc.). The UE may additionally transmit an SRS, for example, in the last symbol of a slot. The SRS may have a comb structure, and the UE may transmit the SRS in one of the combs. In the example of FIG. 4C , the illustrated SRS is comb 2 spanning one symbol. The SRS may be used by the base station to obtain channel state information (CSI) for each UE. The CSI describes how an RF signal propagates from the UE to the base station and represents the combined effects of scattering, fading, and power attenuation with distance. The system uses the SRS for resource scheduling, link adaptation, massive MIMO, beam management, etc.

[0091] Currently, an SRS resource can span 1, 2, 4, 8, or 12 consecutive symbols within a slot with comb sizes Comb 2, Comb 4, or Comb 8. Below are the symbol-to-symbol frequency offsets for the currently supported SRS comb patterns: 1 Symbol Com2: {0}, 2 Symbol Com2: {0, 1}, 4 Symbol Com2: {0, 1, 0, 1}, 4 Symbol Com4: {0, 2, 1, 3}, 8 Symbol Com4: {0, 2, 1, 3, 0, 2, 1, 3}, 12 Symbol Com4: {0, 2, 1, 3, 0, 2, 1, 3, 0, 2, 1, 3}, 4 Symbol Com8: {0, 4, 2, 6}, 8 Symbol Com8: {0, 4, 2, 6, 1, 5, 3, 7}, and 12 Symbol Com8: {0, 4, 2, 6, 1, 5, 3, 7, 0, 4, 2, 6}.

[0092] A set of resource elements used for transmitting an SRS is called an "SRS resource" and may be identified by a parameter "SRS-ResourceId." The set of resource elements may span multiple PRBs in the frequency domain and N (e.g., one or more) consecutive symbols within a slot in the time domain. Within a given OFDM symbol, SRS resources occupy consecutive PRBs. An "SRS resource set" is a set of SRS resources used for transmitting an SRS signal and is identified by an SRS resource set ID ("SRS-ResourceSetId").

[0093] Generally, a UE transmits an SRS to enable a receiving base station (either a serving base station or a neighboring base station) to measure the channel quality between the UE and the base station. However, the SRS may also be specifically configured as an uplink positioning reference signal for uplink-based positioning procedures such as uplink time difference of arrival (UL-TDOA), round-trip time (RTT), and uplink angle-of-arrival (UL-AoA). As used herein, the term “SRS” may refer to an SRS configured for channel quality measurement or an SRS configured for positioning purposes. When it is necessary to distinguish between the two types of SRS, the former may be referred to herein as a “communication SRS” and / or the latter as a “positioning SRS.”

[0094] Several extensions beyond the previous definition of SRS have been proposed for positioning SRS (also called "UL-PRS"), such as a new staggered pattern in SRS resources (except for single symbol / comb2), a new comb type for SRS, a new sequence for SRS, more SRS resource sets per component carrier, and more SRS resources per component carrier. In addition, the parameters "SpatialRelationInfo" and "PathLossReference" will be configured based on downlink reference signals or SSBs from neighboring TRPs. Still further, one SRS resource may be transmitted outside the active BWP, and one SRS resource may span multiple component carriers. Also, the SRS may be configured in the RRC connected state and may only be transmitted within the active BWP. Furthermore, there may be no frequency hopping, no repetition factor, a single antenna port, and new lengths for the SRS (e.g., 8 and 12 symbols). Also, there may be open-loop power control rather than closed-loop power control, and Com8 (i.e., SRS transmitted on every 8th subcarrier in the same symbol) may be used. Finally, the UE may transmit from multiple SRS resources over the same transmit beam for UL-AoA. All of these are additional features to the current SRS framework, configured through RRC higher layer signaling (and potentially triggered or activated through the MAC Control Element (CE) or DCI).

[0095] FIG. 4D illustrates an example of various channels within an uplink slot of a frame according to an aspect of the present disclosure. A random access channel (RACH), also referred to as a physical random access channel (PRACH), may be present within one or more slots within a frame based on a PRACH configuration. The PRACH may include six consecutive RB pairs within a slot. The PRACH enables a UE to perform initial system access and achieve uplink synchronization. A physical uplink control channel (PUCCH) may be located on the edge of the uplink system bandwidth. The PUCCH carries uplink control information (UCI), such as scheduling requests, CSI reports, channel quality indicators (CQIs), precoding matrix indicators (PMIs), rank indicators (RIs), and HARQ ACK / NACK feedback. The physical uplink shared channel (PUSCH) carries data and may additionally be used to carry buffer status reports (BSRs), power headroom reports (PHRs), and / or UCI.

[0096] It should be noted that the terms "positioning reference signal" and "PRS" generally refer to specific reference signals used for positioning in NR and LTE systems. However, as used herein, the terms "positioning reference signal" and "PRS" may also refer to any type of reference signal that can be used for positioning, such as, but not limited to, PRS, TRS, PTRS, CRS, CSI-RS, DMRS, PSS, SSS, SSB, SRS, UL-PRS, as defined in LTE and NR. In addition, the terms "positioning reference signal" and "PRS" may refer to downlink or uplink positioning reference signals, unless otherwise specified by the context. If necessary to further distinguish between types of PRS, downlink positioning reference signals may be referred to as "DL-PRS," and uplink positioning reference signals (e.g., SRS, PTRS for positioning) may be referred to as "UL-PRS." Additionally, for signals that can be transmitted in both the uplink and downlink (e.g., DMRS, PTRS), "UL" or "DL" may be prepended to the signal to distinguish the direction. For example, "UL-DMRS" may be distinguished from "DL-DMRS."

[0097] NR supports several cellular network-based positioning techniques, including downlink-based positioning methods, uplink-based positioning methods, and downlink- and uplink-based positioning methods. Downlink-based positioning methods include observed time difference of arrival (OTDOA) in LTE, downlink time difference of arrival (DL-TDOA) in NR, and downlink angle-of-departure (DL-AoD) in NR. In an OTDOA or DL-TDOA positioning procedure, a UE measures the differences between the times of arrival (ToA) of reference signals (e.g., PRS, TRS, CSI-RS, SSB, etc.) received from pairs of base stations, called reference signal time difference (RSTD) or time difference of arrival (TDOA) measurements, and reports them to a positioning entity. More specifically, the UE receives identifiers (IDs) of a reference base station (e.g., a serving base station) and multiple non-reference base stations in assistance data. The UE then measures RSTD between the reference base station and each of the non-reference base stations. Based on the known locations of the involved base stations and the RSTD measurements, the positioning entity can estimate the location of the UE.

[0098] For DL-AoD positioning, the positioning entity uses beam reports from the UE of received signal strength measurements of multiple downlink transmit beams to determine the angle between the UE and the transmitting base station. The positioning entity can then estimate the location of the UE based on the determined angle and the known location of the transmitting base station.

[0099] Uplink-based positioning methods include uplink time difference of arrival (UL-TDOA) and uplink angle-of-arrival (UL-AoA). UL-TDOA is similar to DL-TDOA, but is based on uplink reference signals (e.g., SRS) transmitted by the UE. For UL-AoA positioning, one or more base stations measure the received signal strength of one or more uplink reference signals (e.g., SRS) received from the UE on one or more uplink receive beams. The positioning entity uses the signal strength measurements and the angles of the receive beams to determine the angle between the UE and the base station. Based on the determined angle and the known location of the base station, the positioning entity can then estimate the location of the UE.

[0100] Downlink and uplink-based positioning methods include extended cell ID (E-CID) positioning and multi-round trip time (RTT) positioning (also called "multi-cell RTT"). In the RTT procedure, an initiator (base station or UE) transmits an RTT measurement signal (e.g., PRS or SRS) to a responder (UE or base station), and the responder transmits an RTT response signal (e.g., SRS or PRS) back to the initiator. The RTT response signal includes the difference between the ToA of the RTT measurement signal and the transmission time of the RTT response signal, called the receive-to-transmit (Rx-Tx) time difference. The initiator calculates the difference between the transmission time of the RTT measurement signal and the ToA of the RTT response signal, called the transmit-to-receive (Tx-Rx) time difference. The propagation time (also called "time of flight") between the initiator and the responder can be calculated from the Tx-Rx time difference and the Rx-Tx time difference. Based on the propagation time and the known speed of light, the distance between the initiator and responder may be determined. For multi-RTT positioning, the UE performs RTT procedures with multiple base stations to allow the UE's location to be determined (e.g., using multilateration) based on the known locations of the base stations. RTT and multi-RTT methods may be combined with other positioning techniques, such as UL-AoA and DL-AoD, to improve location accuracy.

[0101] The E-CID positioning method is based on radio resource management (RRM) measurements. In E-CID, the UE reports the serving cell ID, timing advance (TA), and the identities, estimated timing, and signal strength of detected neighboring base stations. The UE's location is then estimated based on this information and the known locations of the base stations.

[0102] To assist in positioning operations, a location server (e.g., location server 230, LMF 270, SLP 272) may provide assistance data to the UE. For example, the assistance data may include identifiers of base stations (or base station cells / TRPs) from which to measure reference signals, reference signal configuration parameters (e.g., number of consecutive positioning subframes, periodicity of positioning subframes, muting sequence, frequency hopping sequence, reference signal identifier, reference signal bandwidth, etc.), and / or other parameters applicable to a particular positioning method. Alternatively, the assistance data may originate directly from the base station itself (e.g., in periodically broadcast overhead messages, etc.), and in some cases, the UE may be able to detect neighboring network nodes itself without using the assistance data.

[0103] In the case of OTDOA or DL-TDOA positioning procedures, the assistance data may further include an expected RSTD value and an associated uncertainty around the expected RSTD, i.e., a search window. In some cases, the value range for the expected RSTD may be + / - 500 microseconds (μs). In some cases, when any of the resources used for positioning measurements are in FR1, the value range for the expected RSTD uncertainty may be + / - 32 μs. In other cases, when all of the resources used for positioning measurements are in FR2, the value range for the expected RSTD uncertainty may be + / - 8 μs.

[0104] A location estimate may be referred to by other names, such as a position estimate, location, position, position fix, fix, etc. A location estimate may be geodetic and comprise coordinates (e.g., latitude, longitude, and possibly altitude), or may be urban and comprise a street address, postal address, or some other linguistic description of the location. A location estimate may also be specified relative to some other known location or may be specified in absolute terms (e.g., using latitude, longitude, and possibly altitude). A location estimate may include an expected error or uncertainty (e.g., by including an area or volume that the location is expected to fall within, with some specified or default level of confidence).

[0105] 5 is a diagram 500 illustrating a base station (BS) 502 (which may correspond to any of the base stations described herein) communicating with a UE 504 (which may correspond to any of the UEs described herein). Referring to FIG. 5, the base station 502 may transmit beamformed signals to the UE 504 in one or more transmit beams 502a, 502b, 502c, 502d, 502e, 502f, 502g, 502h, each having a beam identifier that may be used by the UE 504 to identify the respective beam. If the base station 502 is beamforming toward the UE 504 with a single array of antennas (e.g., a single TRP / cell), the base station 502 may perform “beam sweeping” by transmitting a first beam 502a, then a beam 502b, etc., until finally transmitting beam 502h. Alternatively, the base station 502 may transmit the beams 502a-502h in several patterns, such as beam 502a, then beam 502h, then beam 502b, then beam 502g, etc. If the base station 502 is beamforming towards the UE 504 using multiple arrays of antennas (e.g., multiple TRPs / cells), each antenna array may perform beam sweeping of a subset of the beams 502a-502h. Alternatively, each of the beams 502a-502h may correspond to a single antenna or antenna array.

[0106] 5 further illustrates paths 512c, 512d, 512e, 512f, and 512g followed by beamformed signals transmitted on beams 502c, 502d, 502e, 502f, and 502g, respectively. Each path 512c, 512d, 512e, 512f, and 512g may correspond to a single “multipath” or may be composed of multiple (clusters of) “multipaths” due to the propagation characteristics of radio frequency (RF) signals through the environment. While only the paths for beams 502c-502g are shown, this is for simplicity's sake; note that the signals transmitted in each of beams 502a-502h follow several paths. In the illustrated example, paths 512c, 512d, 512e, and 512f are straight lines, while path 512g reflects off an obstacle 520 (e.g., a building, a vehicle, a terrain feature, etc.).

[0107] The UE 504 may receive beamformed signals from the base station 502 in one or more receive beams 504a, 504b, 504c, 504d. Note that for simplicity, the beams shown in FIG. 5 represent either transmit or receive beams, depending on which of the base station 502 and the UE 504 is transmitting and which is receiving. Thus, the UE 504 may also transmit beamformed signals to the base station 502 in one or more of the beams 504a-504d, and the base station 502 may receive beamformed signals from the UE 504 in one or more of the beams 502a-502h.

[0108] In one aspect, the base station 502 and the UE 504 may perform beam training to align the transmit and receive beams of the base station 502 and the UE 504. For example, depending on environmental conditions and other factors, the base station 502 and the UE 504 may determine that the best transmit and receive beams are 502d and 504b, respectively, or beams 502e and 504c, respectively. The direction of the best transmit beam for the base station 502 may or may not be the same as the direction of the best receive beam, and similarly, the direction of the best receive beam for the UE 504 may or may not be the same as the direction of the best transmit beam. However, it should be noted that the transmit and receive beams do not need to be aligned to perform downlink angle-of-departure (DL-AoD) or uplink angle-of-arrival (UL-AoA) positioning procedures.

[0109] To perform the DL-AoD positioning procedure, the base station 502 may transmit reference signals (e.g., PRS, CRS, TRS, CSI-RS, PSS, SSS, etc.) to the UE 504 in one or more of the beams 502a-502h, with each beam having a different transmit angle. The different transmit angles of the beams result in different received signal strengths (e.g., RSRP, RSRQ, SINR, etc.) at the UE 504. In particular, the received signal strength is smaller for transmit beams 502a-502h that are farther from the line-of-sight (LOS) path 510 between the base station 502 and the UE 504 than for transmit beams 502a-502h that are closer to the LOS path 510.

[0110] 5, when the base station 502 transmits reference signals to the UE 504 on beams 502c, 502d, 502e, 502f, and 502g, the transmit beam 502e is best aligned with the LOS path 510, but the transmit beams 502c, 502d, 502f, and 502g are not. Thus, the beam 502e may have a greater received signal strength at the UE 504 than the beams 502c, 502d, 502f, and 502g. Note that the reference signals transmitted on some beams (e.g., beams 502c and / or 502f) may not reach the UE 504, or the energy reaching the UE 504 from these beams may be so low that the energy may not be detectable or at least may be ignored.

[0111] The UE 504 may report the received signal strength of each measured transmit beam 502c-502g and, optionally, the associated measurement quality to the base station 502, or alternatively, the identity of the transmit beam with the greatest received signal strength (beam 502e in the example of FIG. 5). Alternatively or additionally, if the UE 504 is also involved in a round-trip time (RTT) or time difference of arrival (TDOA) positioning session with at least one or multiple base stations 502, respectively, the UE 504 may report receive-to-transmit (Rx-Tx) time difference or reference signal time difference (RSTD) measurements (and, optionally, the associated measurement quality) to the serving base station 502 or other positioning entity, respectively. In either case, the positioning entity (e.g., base station 502, location server, third-party client, UE 504, etc.) can estimate the angle from base station 502 to UE 504 as the AoD of the transmit beam with the greatest received signal strength at UE 504, here transmit beam 502e.

[0112] In one aspect of DL-AoD-based positioning, where only one base station 502 is involved, the base station 502 and the UE 504 may perform a round-trip time (RTT) procedure to determine the distance between the base station 502 and the UE 504. Thus, the positioning entity may determine both the direction to the UE 504 (using DL-AoD positioning) and the distance to the UE 504 (using RTT positioning) to estimate the location of the UE 504. Note that the AoD of the transmit beam with the greatest received signal strength does not necessarily lie along the LOS path 510 as shown in FIG. 5 . However, for DL-AoD-based positioning purposes, this is assumed to be the case.

[0113] In another aspect of DL-AoD-based positioning where there are multiple base stations 502 involved, each participating base station 502 can report the determined AoD or RSRP measurements from its respective base station 502 to the UE 504 to the serving base station 502. The serving base station 502 may then report the AoD or RSRP measurements from the other participating base stations 502 to a positioning entity (e.g., the UE 504 in the case of UE-based positioning, or a location server in the case of UE-assisted positioning). Using this information and knowledge of the geographic locations of the base stations 502, the positioning entity can estimate the location of the UE 504 as the intersection of the determined AoDs. For a two-dimensional (2D) location solution, there should be at least two base stations 502 involved, but as will be appreciated, the more base stations 502 involved in the positioning procedure, the more accurate the estimated location of the UE 504 will be.

[0114] To perform the UL-AoA positioning procedure, the UE 504 transmits uplink reference signals (e.g., UL-PRS, SRS, DMRS, etc.) to the base station 502 in one or more of the uplink transmit beams 504a-504d. The base station 502 receives the uplink reference signals in one or more of the uplink receive beams 502a-502h. The base station 502 determines the angle of the best receive beam 502a-502h used to receive one or more reference signals from the UE 504 as the AoA from the UE 504 to itself. In particular, each of the receive beams 502a-502h results in a different received signal strength (e.g., RSRP, RSRQ, SINR, etc.) of one or more reference signals at the base station 502. Furthermore, the channel impulse response of one or more reference signals is smaller for receive beams 502a-502h that are farther from the actual LOS path between the base station 502 and the UE 504 than for receive beams 502a-502h that are closer to the LOS path. Similarly, the received signal strength is smaller for receive beams 502a-502h that are farther from the LOS path than for receive beams 502a-502h that are closer to the LOS path. Thus, the base station 502 identifies the receive beam 502a-502h that provides the greatest received signal strength, and optionally the strongest channel impulse response, and estimates the angle from itself to the UE 504 as the AoA of that receive beam 502a-502h. Note that, as in the DL-AoD-based case, the AoA of the receive beam 502a-502h that provides the greatest received signal strength (and, if measured, the strongest channel impulse response) is not necessarily along the LOS path 510. However, for UL-AoA based positioning purposes in FR2, this may be assumed to be the case.

[0115] Note that while the UE 504 is shown as being capable of beamforming, this is not required for DL-AoD and UL-AoA positioning procedures. Rather, the UE 504 may receive and transmit on an omni-directional antenna.

[0116] If the UE 504 is estimating its location (i.e., the UE is a positioning entity), it needs to obtain the geographic location of the base station 502. The UE 504 may obtain the location, for example, from the base station 502 itself or from a location server (e.g., location server 230, LMF 270, SLP 272). With knowledge of the distance to the base station 502 (based on the RTT or timing advance), the angle between the base station 502 and the UE 504 (based on the UL-AoA of the best received beam 502a-502h), and the known geographic location of the base station 502, the UE 504 can estimate its location.

[0117] Alternatively, if a positioning entity, such as the base station 502 or a location server, is estimating the location of the UE 504, the base station 502 reports the AoA of the receive beams 502a-502h that results in the greatest received signal strength (and optionally the strongest channel impulse response) of the reference signal received from the UE 504, or all received signal strengths and channel impulse responses for all receive beams 502 (allowing the positioning entity to determine the best receive beam 502a-502h). The base station 502 may additionally report the Rx-Tx time difference to the UE 504. The positioning entity can then estimate the location of the UE 504 based on the distance of the UE 504 to the base station 502, the AoA of the identified receive beams 502a-502h, and the known geographic location of the base station 502.

[0118] FIG. 6 illustrates an example system 600 for wireless communications using a reconfigurable intelligent surface (RIS) 610 according to an embodiment of the present disclosure. The RIS (e.g., RIS 610) is a two-dimensional surface comprising a large number of low-cost, low-power, and mostly passive reflective elements whose characteristics are not static but are reconfigurable (by software). For example, by carefully adjusting the phase shifts of the reflective elements (using software), the scattering, absorption, reflection, and diffraction properties of the RIS can be altered over time. In that way, the electromagnetic (EM) properties of the RIS can be designed to collect wireless signals from a transmitter (e.g., a base station, a UE, etc.) and passively beamform them toward a target receiver (e.g., another base station, another UE, etc.). In the example of FIG. 6, a first base station 602-1 controls the reflective properties of the RIS 610 to communicate with a first UE 604-1.

[0119] The goal of RIS technology is to create a smart radio environment where wireless propagation conditions are co-designed with physical layer signaling. This expanded functionality of system 600 can provide technical benefits in several scenarios.

[0120] 6, a first base station 602-1 (e.g., any of the base stations described herein) is attempting to transmit downlink wireless signals to a first UE 604-1 and a second UE 604-2 (e.g., any two of the UEs described herein, collectively UEs 604) on multiple downlink transmit beams labeled “0,” “1,” “2,” and “3.” However, unlike the second UE 604-2, the first UE 604-1 is behind an obstruction 620 (e.g., a building, a hill, or another type of obstruction) and is therefore unable to receive wireless signals on what would otherwise be a line-of-sight (LOS) beam from the first base station 602-1, i.e., the downlink transmit beam labeled “2.” In this scenario, the first base station 602-1 may instead use a downlink transmit beam labeled "1" to transmit wireless signals to the RIS 610, and may configure the RIS 610 to reflect / beamform the incident wireless signals toward the first UE 604-1. The first base station 602-1 may thereby transmit wireless signals around the obstacle 620.

[0121] It should be noted that the first base station 602-1 may also configure the RIS 610 for use by the first UE 604-1 in the uplink. In that case, the first base station 602-1 may configure the RIS 610 to reflect an uplink signal from the first UE 604-1 to the first base station 602-1, thereby allowing the first UE 604-1 to transmit the uplink signal around the obstacle 620.

[0122] As another example scenario in which the system 600 may provide a technical advantage, the first base station 602-1 may be aware that an obstacle 620 may create a "dead zone," i.e., a geographic area where downlink wireless signals from the first base station 602-1 are so attenuated that they cannot be reliably detected by UEs (e.g., the first UE 604-1) within that area. In this scenario, the first base station 602-1 may configure the RIS 610 to reflect downlink wireless signals into the dead zone to provide coverage to UEs that may be located in the dead zone, including UEs that the first base station 602-1 is unaware of.

[0123] 6 also shows a second base station 602-2 that may transmit downlink wireless signals to one or both of the UEs 604. As an example, the first base station 602-1 may be a serving base station for the UEs 604, and the second base station 602-2 may be a neighboring base station. The second base station 602-2 may transmit downlink positioning reference signals to one or both of the UEs 604 as part of a positioning procedure involving the UEs 604. Alternatively or additionally, the second base station 602-2 may be a secondary cell for one or both of the UEs 604. In some cases, the second base station 602-2 may also be able to reconfigure the RIS 610, provided that the RIS 610 is not then controlled by the first base station 602-1.

[0124] Referring to FIG. 6 , the RIS 610 may be either a Mode 1 RIS, which is essentially a reconfigurable mirror, or a Mode 2 RIS, which is more extended and supports repeater mode operation (amplify and forward). For a Mode 1 RIS, it is assumed that the hardware group delay at the RIS is negligible. For a Mode 2 RIS, in some designs, it may be assumed that the hardware group delay of each RIS is not negligible. In this case, each gNB may further indicate whether each Mode 2 RIS supports baseband processing and may calculate and / or report the associated Rx-Tx time difference. In some designs, the gNB may also report whether the RIS can calculate / report its Rx-Tx time difference.

[0125] FIG. 7 is a diagram of an exemplary architecture of a RIS 700 according to an embodiment of the present disclosure. As shown in FIG. 7, the RIS 700 (which may correspond to the RIS 610 in FIG. 6) mainly consists of a flat surface 710 and a controller 720. The flat surface 710 may be constructed of one or more layers of material. In the example of FIG. 7, the flat surface 710 may consist of three layers. In this case, the outer layer has multiple reflective elements 712 printed on a dielectric substrate to directly act on the incident signal. The middle layer is a copper panel to avoid signal / energy leakage. The final layer is a circuit board used to adjust the reflection coefficient of the reflective elements 712 and is operated by a controller 720. The controller 720 may be a low-power processor such as a field-programmable gate array (FPGA).

[0126] In a typical operating scenario, the optimal reflection coefficients for the RIS 700 are calculated at a base station (e.g., the first base station 602-1 in FIG. 6) and then sent to the controller 720 over a dedicated feedback link. The design of the reflection coefficients relies on channel state information (CSI), which is updated only when the CSI changes, which is on a timescale much longer than the data symbol duration. Therefore, a low rate of information exchange is sufficient for the dedicated control link, which can be implemented using low-cost copper wire or a simple, cost-effective wireless transceiver.

[0127] Each reflective element 712 is coupled to a p-type intrinsic n-type (PIN) positive-intrinsic negative diode 714. In addition, bias lines 716 connect each reflective element 712 in a row to a controller 720. By controlling the voltage through the bias lines 716, the PIN diodes 714 can be switched between an "on" mode and an "off" mode. This can achieve a phase shift difference of π (pi) in radians. To increase the number of phase shift levels, more PIN diodes 714 can be coupled to each reflective element 712.

[0128] A RIS such as the RIS700 has important advantages for practical implementation. For example, the reflective element 712 merely passively reflects the incident signal without any sophisticated signal processing operations that would require RF transceiver hardware. Therefore, compared to conventional active transmitters, the RIS700 can operate at orders of magnitude lower costs in terms of hardware and power consumption. Additionally, due to the passive nature of the reflective element 712, the RIS700 can be fabricated with low weight and limited layer thickness, and thus can be easily installed on walls, ceilings, signs, streetlights, and the like. Furthermore, the RIS700 operates naturally in full-duplex (FD) mode without self-interference or introducing thermal noise. Therefore, the RIS700 can achieve higher spectral efficiency than active half-duplex (HD) relays, despite the signal processing complexity of the RIS700 being less than that of active FD relays, which require sophisticated self-interference cancellation.

[0129] As mentioned above, various device types may be characterized as UEs. Starting with 3GPP® Rel. 17, some of these UE types (so-called low-tier UEs) are being assigned a new UE classification, denoted as reduced capabilities ("RedCap") or "NR-Light." Examples of UE types that fall under the RedCap classification include wearable devices (e.g., smart watches, etc.), industrial sensors, video cameras (e.g., surveillance cameras, etc.). Generally, UE types grouped under the RedCap classification are associated with smaller communication capacities. For example, compared to "normal" UEs (e.g., UEs not classified as RedCap), RedCap UEs may be limited in terms of maximum bandwidth (e.g., 5 MHz, 10 MHz, 20 MHz, etc.), maximum transmit power (e.g., 20 dBm, 14 dBm, etc.), number of receive antennas (e.g., one receive antenna, two receive antennas, etc.), etc. Some RedCap UEs may also be sensitive to power consumption (e.g., requiring a long battery life, such as several years) and may be highly mobile. Moreover, in some designs, it is generally desirable for RedCap UEs to coexist with UEs implementing protocols such as eMBB, URLLC, and LTE NB-IoT / MTC.

[0130] Due to its limited capabilities, a RedCap UE may have difficulty hearing or detecting PRS (e.g., due to limited receive bandwidth, Rx antennas, baseband processing capabilities, etc.), especially from non-serving gNBs that may be farther away from the RedCap UE than the serving gNB. Similarly, a RedCap UE may be associated with poor SRS measurements (e.g., limited ability to measure UL-SRS-P at one or more neighboring gNBs, limited ability to measure UL-SRS-P reflections from the RIS by the UE itself, etc.). In some designs, a low-power UE positioning scheme may be implemented for a RedCap UE. However, such implementations generally require the RedCap UE to be within the coverage (e.g., UL and DL coverage) of the serving and non-serving gNBs. In some designs, the RIS can be treated as a positioning anchor for RIS-assisted positioning of the UE (e.g., particularly for indoor scenarios).

[0131] Aspects of the present disclosure are thereby directed to location assistance data for RIS-assisted positioning. Such aspects may provide various technical advantages, such as improved positioning accuracy, particularly for indoor positioning, positioning of RedCap UEs, etc.

[0132] 8 illustrates an example process 800 of communication according to one aspect of the present disclosure. The process 800 of FIG. 8 is performed by a UE, which may correspond to the UE 302 as an example.

[0133] 8, at 810, the UE 302 (e.g., receiver 312 or 322, etc.) receives location assistance data from a network component (e.g., a base station) including information related to one or more RISs. In some designs, the network component may correspond to a serving gNB for the UE 302. In other designs, the network component may correspond to an LMF or a location server. In one example, the location assistance data may be broadcast location assistance data (e.g., sent within a particular location area to any listening UEs) or unicast location assistance data (e.g., sent to a specific UE based on UE-specific information). As described in more detail below, various types of information related to the RISs may be sent. In one example, the means for performing the receiving at 810 may include the receiver 312 or 322 of the UE 302.

[0134] 8, at 820, the UE 302 (e.g., receiver 312 or 322, transmitter 314 or 324, processing system 332, RIS module 342, etc.) performs one or more location procedures based on the location assistance data. As will be described in more detail, various types of location procedures may be performed at 820, such as transmitting an UL or SL SRS-P via reflection from the RIS, measuring a DL-PRS or SL-PRS reflected from the RIS (e.g., ToA, RSRP, DL-AoD, etc.). In one example, the means for performing the location procedures at 820 may include the receiver 312 or 322, the transmitter 314 or 324, the processing system 332, the RIS module 342, etc.

[0135] 9 illustrates an example process 900 of communication according to one aspect of the present disclosure. The process 900 of FIG. 9 is performed by a network component, which may correspond to the BS 304, an LMF, or a location server (e.g., integrated with the BS 304 or at a network entity 306, such as a core network component or a remote server).

[0136] 9, at 910, a network component (e.g., processing system 384 or 394, RIS module 388 or 398, etc.) determines location assistance data comprising information related to one or more RISs. As described in more detail below, various types of information may be sent related to a RIS. In one example, the means for performing the determination of 910 may include processing system 384 or 394, RIS module 388 or 398, etc., of BS 304 or network entity 306.

[0137] 9 , at 920, a network component (e.g., transmitter 354 or 364, network interface 390, etc.) transmits location assistance data to the UE to facilitate one or more location procedures based on the location assistance data. In one example, the location assistance data may be broadcast location assistance data (e.g., sent within a specific location area to any listening UEs) or unicast location assistance data (e.g., sent to a specific UE based on UE-specific information). As will be described in more detail, various types of location procedures may be performed based on the location assistance data, such as transmitting an UL or SL SRS-P via reflection from a RIS, measuring a DL-PRS or SL-PRS reflected from a RIS (e.g., ToA, RSRP, DL-AoD, etc.). In one example, the means for performing the transmission of 920 may include a transmitter 354 or 364, a network interface 390, etc., of the BS 304 or the network entity 306.

[0138] 8-9 , in some designs, the information may include notification of the presence of one or more RISs within an area. In some designs, the area corresponds to a cell (e.g., if the network does not have any history of the UE 302's location, the network may provide cell-level RIS notification), or the area is based on the UE's position estimate (e.g., if the network has a recent positioning fix for the UE 302, such as within a threshold number of times or x seconds, the network may provide the UE with notification of RIS locations within a threshold distance of the UE 302, such as y meters, i.e., UE location-level notification), or a combination thereof. In some designs, if notification is provided for multiple RISs within a location region, the information in the location assistance data may include a respective RIS identifier for each of the multiple RISs.

[0139] 8-9 , in some designs, one or more location procedures may be associated with a UE-based position estimation of the UE, and the information may include a respective location associated with each of one or more RISs. In contrast, for UE-assisted positioning, the UE 302 need not know the actual RIS location. In other words, in some designs, the RIS location may be known to a position estimation entity but not to all devices associated with transmitting and / or measuring positioning reference signals (RS-Ps), such as DL-PRS, SL-PRS, UL-SRS-P, and SL-SRS-P.

[0140] 8-9 , in some designs, for each of one or more RISs, the information may include an indication of whether the respective RIS is a passive RIS (e.g., a Mode 1 RIS) or a relay RIS (e.g., a Mode 2 RIS capable of amplifying and forwarding RS-P). In some designs, at least one of the one or more RISs is designated as a relay RIS, and the information further includes, for the at least one RIS, an indication of the RIS reflection gain, group delay, or a combination thereof (e.g., for UE-based positioning). For UE-assisted positioning, such information may be omitted from the location assistance data and may instead be known at the position estimation entity, i.e., the LMF. In some designs, the group delay may be calibrated when the RIS is set up and then assumed to be fixed. In other designs, the group delay for the RIS may be measured periodically or more dynamically and updated time-wise (e.g., for each positioning session, etc.).

[0141] 8-9 , in some designs, the one or more location procedures are associated with at least one RS-P communicated between the UE and a wireless node (e.g., a serving gNB or a non-serving gNB, a UE such as a reference UE or anchor UE with a known location from a recent positioning fix, etc.) via reflection from one or more RISs. For example, the at least one RS-P comprises at least one uplink (UL) or sidelink (SL) SRS-P transmitted by the UE, or the at least one RS-P comprises at least one DL-PRS or SL-PRS transmitted by the wireless node, or a combination thereof. In one example, one or more PRSs may be associated with one or more specific RISs (e.g., a network may signal an associated RIS ID when configuring a PRS). Similarly, in another example, one or more SRSs may be associated with one or more specific RISs (e.g., a network may signal an associated RIS ID when configuring an SRS). In some designs, the information may include an association between the at least one RS-P and one or more RISs.

[0142] 8-9 , in some designs, at least one RS-P may include (or may correspond to) at least one DL or SL PRS transmitted by the wireless node. In this case, the information may include first quasi-co-location (QCL) information associated with the downlink or sidelink PRS transmitted by the wireless node, and the information may include second QCL information associated with the at least one RS-P as reflected from one or more RISs. In some designs, the QCL source associated with the first QCL information, the second QCL information, or both may correspond to another RS-P, a signal synchronization block (SSB), or a channel state information reference signal (CSI-RS). For example, in some scenarios, a UE may be expected to conduct positioning measurements using the same positioning RS, both transmitted by the gNB and reflected by the RIS. To improve measurement quality, two sets of QCLs may be configured (e.g., a first set of QCLs related to the gNB's transmissions and a second set of QCLs related to the RIS's reflections). In this case, the QCL source may be another positioning RS or SSB / CSIRS. The RIS may reflect the SSB / CSIRS transmitted by the gNB, and thus the UE can find the reference Rx beam for receiving the signal reflected by the RIS through measuring the reflected SSB / CSIRS.

[0143] 8-9 , in some legacy NR positioning systems, location assistance data includes nr-DL-PRS-ExpectedRSTD and nr-DL-PRS-ExpectedRSTD-Uncertainty for each pair of DL PRS resource sets (target gNB and reference gNB). For example, a UE may be configured with higher layer parameters nr-DL-PRS-ExpectedRSTD, which specifies a time difference relative to the received DL subframe timing at which the UE is expected to receive the DL PRS, and nr-DL-PRS-ExpectedRSTD-Uncertainty, which specifies a search window around the expected RSTD. In some designs, at least one RS-P communicated between the UE 302 and the wireless node via the RIS may include one or more PRS search window parameters. In some designs, the one or more PRS search window parameters may include an expected reference signal time difference (RSTD) or expected RSTD uncertainty associated with the arrival of at least one downlink or sidelink PRS to the UE. In a more detailed example, the new timing uncertainty parameters may be named "nr-RIS-DL-PRS-ExpectedRSTD" and "nr-RIS-DL-PRS-ExpectedRSTD-Uncertainty," and they are derived based on the location of the RIS. "nr-RIS-DL-PRS-ExpectedRSTD" may specify a time difference relative to the received DL subframe timing at which the UE expects to receive the DL-PRS reflected by a particular RIS. "nr-RIS-DL-PRS-ExpectedRSTD-Uncertainty" may specify a search window around "nr-RIS-DL-PRS-ExpectedRSTD." The UE may be guided to optimize reception of the PRS reflected at the RIS based on "nr-RIS-DL-PRS-ExpectedRSTD" and "nr-RIS-DL-PRS-ExpectedRSTD-Uncertainty."

[0144] 8-9 , in some designs, the one or more location procedures may include a downlink angle-of-departure (DL-AoD) positioning session for the UE. In a further example, the information may include beam information for each positioning reference signal (PRS) for one or more RISs. Some of the beam information may be associated with boresight, as shown in configuration 1000 of FIG. 10 . More specifically, in some designs, the beam information may include: PRS identifiers and associated RIS identifiers, or RIS orientation (e.g., to calculate the boresight direction, e.g., azimuth angle α, downtilt angle β, and tilt angle γ, which can be used to transform the RIS orientation from a location coordinate system (LCS) to a group coordinate system (GCS)); or Azimuth and altitude of each PRS beam, or the beamwidth of each PRS beam (e.g., the beamwidth may be 3 dB / 6 dB / 12 dB beamwidth, and the beamwidth may be labeled with its beam spatial dimensions, e.g., azimuth and elevation), or Boresight direction or beamwidth uncertainty (e.g., boresight / beamwidth uncertainty may be a 0.5dB / 1dB / 3dB-based measurement, e.g., beamwidth uncertainty should be labeled with its beam space dimension) or One or more sidelobe or backlobe power levels relative to the boresight (e.g., -20 dB); or · A combination of these may include:

[0145] In the above detailed description, it can be seen that various features are grouped together in the examples. This manner of disclosure should not be understood as an intention that the example clauses have more features than are expressly recited in each clause. Rather, various aspects of the present disclosure may include fewer than all features of each example clause disclosed. Accordingly, the following clauses are hereby considered to be incorporated into this description, and each clause may stand alone as a separate example. Although each dependent clause may refer to a specific combination with one of the other clauses within that clause, the aspects of that dependent clause are not limited to that specific combination. It will be appreciated that other example clauses can also include combinations of aspects of that dependent clause with the subject matter of any other dependent clause or independent clause, or combinations of any features with other dependent clauses and independent clauses. The various aspects disclosed herein expressly include combinations of these combinations unless a particular combination is expressly expressed or can be readily inferred (e.g., contradictory aspects, such as defining an element as both an insulator and a conductor). It is further contemplated that aspects of a clause may be included within any other independent clause, even if the clause is not directly dependent on the independent clause.

[0146] Example implementations are described in the following numbered clauses.

[0147] Clause 1. A method of operating a user equipment (UE), comprising receiving location assistance data from a network component, the location assistance data comprising information relating to one or more reconfigurable intelligent surfaces (RISs), and performing one or more location procedures based on the location assistance data.

[0148] Clause 2. The method of clause 1, wherein the information comprises notification of the presence of one or more RISs in the area.

[0149] Clause 3. The method of clause 2, wherein the area corresponds to a cell, or the area is based on a location estimate of the UE, or a combination thereof.

[0150] Clause 4. The method of any of clauses 2-3, wherein the one or more RISs include a plurality of RISs, and the information comprises a respective RIS identifier for each of the plurality of RISs.

[0151] Clause 5. The method of any of clauses 1-4, wherein the one or more location procedures are associated with a UE-based position estimation of the UE, and the information comprises a respective location associated with each of the one or more RISs.

[0152] Clause 6. The method of any of clauses 1-5, wherein, for each of the one or more RISs, the information comprises an indication of whether the respective RIS is a passive RIS or a relay RIS.

[0153] Clause 7. The method of clause 6, wherein at least one of the one or more RISs is designated as a relay RIS, and the information further includes, for the at least one RIS, an indication of the gain, group delay, or a combination thereof, of the RIS reflection.

[0154] Clause 8. The method of any of clauses 1-7, wherein the one or more location procedures are associated with at least one positioning reference signal (RS-P) communicated between the UE and the wireless node via reflections from one or more RISs.

[0155] Clause 9. The method of clause 8, wherein the at least one RS-P comprises at least one uplink or sidelink sounding reference signal for positioning (SRS-P) transmitted by the UE, or the at least one RS-P comprises at least one downlink or sidelink positioning reference signal (PRS) transmitted by the wireless node, or a combination thereof.

[0156] Clause 10. The method of clause 9, wherein the at least one RS-P comprises at least one downlink or sidelink PRS transmitted by the wireless node, the information comprises first quasi-co-location (QCL) information associated with the at least one downlink or sidelink PRS transmitted by the wireless node, and the information comprises second QCL information associated with the at least one RS-P as reflected from one or more RISs.

[0157] Clause 11. The method of clause 10, wherein the QCL source associated with the first QCL information, the second QCL information, or both, corresponds to another RS-P, a signal synchronization block (SSB), or a channel state information reference signal (CSI-RS).

[0158] Clause 12. The method of any of clauses 9-11, wherein the at least one RS-P comprises at least one PRS transmitted by the wireless node, and the information comprises one or more PRS search window parameters.

[0159] Clause 13. The method of clause 12, wherein the one or more PRS search window parameters comprise an expected reference signal time difference (RSTD) or expected RSTD uncertainty associated with arrival of at least one downlink or sidelink PRS to the UE.

[0160] Clause 14. The method of any of clauses 8-13, wherein the information comprises an association between at least one RS-P and one or more RISs.

[0161] Clause 15. The method of any of clauses 1-14, wherein the one or more location procedures comprise a downlink angle-of-departure (DL-AoD) positioning session of the UE.

[0162] Clause 16. The method of clause 15, wherein the information comprises beam information for each positioning reference signal (PRS) for one or more RISs.

[0163] Clause 17. The method of clause 16, wherein the beam information includes a PRS identifier and associated RIS identifier, or a RIS orientation, or an azimuth and elevation of each PRS beam, or a beamwidth of each PRS beam, or a boresight direction or beamwidth uncertainty, or a power level of one or more sidelobes or backlobes relative to the boresight, or a combination thereof.

[0164] Clause 18. A method of operating a network component, comprising: determining location assistance data comprising information relating to one or more reconfigurable intelligent surfaces (RISs); and transmitting the location assistance data to a user equipment (UE) to facilitate one or more location procedures based on the location assistance data.

[0165] Clause 19. The method of clause 18, wherein the information comprises notification of the presence of one or more RISs in the area.

[0166] Clause 20. The method of clause 19, wherein the area corresponds to a cell, or the area is based on a location estimate of the UE, or a combination thereof.

[0167] Clause 21. The method of any of clauses 19-20, wherein the one or more RISs include a plurality of RISs, and the information comprises a respective RIS identifier for each of the plurality of RISs.

[0168] Clause 22. The method of any of clauses 18-21, wherein the one or more location procedures are associated with a UE-based position estimation of the UE, and the information comprises a respective location associated with each of the one or more RISs.

[0169] Clause 23. The method of any of clauses 18-22, wherein, for each of the one or more RISs, the information comprises an indication of whether the respective RIS is a passive RIS or a relay RIS.

[0170] Clause 24. The method of clause 23, wherein at least one of the one or more RISs is designated as a relay RIS, and the information further includes, for the at least one RIS, an indication of the gain, group delay, or a combination thereof, of the RIS reflection.

[0171] Clause 25. The method of any of clauses 18 to 24, wherein the one or more location procedures are associated with at least one positioning reference signal (RS-P) communicated between the UE and the wireless node via reflections from one or more RISs.

[0172] Clause 26. The method of clause 25, wherein the at least one RS-P comprises at least one uplink or sidelink positioning sounding reference signal (SRS-P) transmitted by the UE, or the at least one RS-P comprises at least one downlink or sidelink positioning reference signal (PRS) transmitted by the wireless node, or a combination thereof.

[0173] Clause 27. The method of clause 26, wherein the at least one RS-P comprises at least one downlink or sidelink PRS transmitted by the wireless node, the information comprises first quasi-co-location (QCL) information associated with the at least one downlink or sidelink PRS transmitted by the wireless node, and the information comprises second QCL information associated with the at least one RS-P as reflected from one or more RISs.

[0174] Clause 28. The method of clause 27, wherein the QCL source associated with the first QCL information, the second QCL information, or both, corresponds to another RS-P, a signal synchronization block (SSB), or a channel state information reference signal (CSI-RS).

[0175] Clause 29. The method of any of clauses 26-28, wherein the at least one RS-P comprises at least one downlink or sidelink PRS transmitted by the wireless node, and the information comprises one or more PRS search window parameters.

[0176] Clause 30. The method of clause 29, wherein the one or more PRS search window parameters comprise an expected reference signal time difference (RSTD) or expected RSTD uncertainty associated with arrival of at least one downlink or sidelink PRS to the UE.

[0177] Clause 31. The method of any of clauses 25-30, wherein the information comprises an association between at least one RS-P and one or more RISs.

[0178] Clause 32. The method of any of clauses 18 to 31, wherein the one or more location procedures comprise a downlink angle-of-departure (DL-AoD) positioning session of the UE.

[0179] Clause 33. The method of clause 32, wherein the information comprises beam information for each positioning reference signal (PRS) for one or more RISs.

[0180] Clause 34. The method of clause 33, wherein the beam information includes a PRS identifier and an associated RIS identifier, or a RIS orientation, or an orientation and elevation of each PRS beam, or a beamwidth of each PRS beam, or a boresight direction or beamwidth uncertainty, or a power level of one or more sidelobes or backlobes relative to the boresight, or a combination thereof.

[0181] Clause 35. An apparatus comprising a memory and at least one processor communicatively coupled to the memory, wherein the memory and the at least one processor are configured to perform a method according to any of clauses 1 to 34.

[0182] Clause 36. Apparatus comprising means for carrying out the method according to any of clauses 1 to 34.

[0183] Clause 37. A non-transitory computer-readable medium storing computer-executable instructions, the computer-executable instructions comprising at least one instruction for causing a computer or processor to perform a method according to any of clauses 1 to 34.

[0184] Those skilled in the art will appreciate that information and signals may be represented using any of a variety of different technologies and techniques. For example, the data, instructions, commands, information, signals, bits, symbols, and chips that may be referenced throughout the above description may be represented by voltages, currents, electromagnetic waves, magnetic fields or particles, optical fields or particles, or any combination thereof.

[0185] Furthermore, those skilled in the art will appreciate that the various illustrative logical blocks, modules, circuits, and algorithm steps described in connection with the aspects disclosed herein may 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.

[0186] The various illustrative logic blocks, modules, and circuits described in connection with the aspects disclosed herein may be implemented or performed using a general-purpose processor, a digital signal processor (DSP), an 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.

[0187] The methods, sequences, and / or algorithms described in connection with the aspects disclosed herein may be embodied directly in hardware, in software modules executed by a processor, or in a combination of the two. The software modules may reside in random access memory (RAM), flash memory, read-only memory (ROM), erasable programmable ROM (EPROM), electrically erasable programmable ROM (EEPROM), registers, hard disk, removable disk, 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 (e.g., UE). Alternatively, the processor and the storage medium may reside as discrete components in the user terminal.

[0188] In one or more exemplary aspects, 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. Storage media may be any available medium that can be accessed by a 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 in the form of instructions or data structures and that can be accessed by a computer. Also, any connection is properly termed a computer-readable medium. For example, if software is transmitted from a website, server, or other remote source using coaxial cable, fiber optic cable, twisted pair, digital subscriber line (DSL), or wireless technologies such as infrared, radio, and microwave, the coaxial cable, fiber optic cable, twisted pair, DSL, or wireless technologies such as infrared, radio, and microwave are included within the definition of medium. Disk and disc, as used herein, include compact discs (CDs), laser discs, optical discs, digital versatile discs (DVDs), floppy disks, and Blu-ray discs, where disks typically reproduce data magnetically and discs reproduce data optically using lasers. Combinations of the above should also be included within the scope of computer-readable media.

[0189] While the above disclosure illustrates exemplary aspects of the present disclosure, it should be noted that various changes and modifications can be made herein without departing from the scope of the present disclosure as defined by the appended claims. The functions, steps, and / or actions of the method claims in accordance with the aspects of the present disclosure described herein need not be performed in any particular order. Furthermore, although elements of the present disclosure may be described or claimed in the singular, the plural is contemplated unless limitation to the singular is explicitly stated. [Explanation of symbols]

[0190] 100 Wireless Communication System 102 Base station (BS) 104 User Equipment (UE) 110 Coverage Area 112 Space Vehicle (SV) 120 Communication Links 122 backhaul links 124 SPS signals 134 backhaul links 150 Wireless Local Area Network (WLAN) Access Points (APs) 152 Wireless Local Area Network (WLAN) Station (STA) 154 communication links 164 User Equipment (UE) 170 Core Network 172 Location Server 180 mmW base station 182 User Equipment (UE) 184 Millimeter Wave (mmW) Communication Link 190 User Equipment (UE) 192, 194 Device-to-Device (D2D) Peer-to-Peer (P2P) Links 200 Wireless Network Structure 204 User Equipment (UE) 210 5G Core (5GC) 212 User Plane Functions 213 User Plane Interface (NG-U) 214 Control Plane Functions 215 Control Plane Interface (NG-C) 220 Next Generation RAN (NG-RAN) 222 gNB 223 Backhaul Connection 224 ng-eNB 230 Location Server 250 Wireless Network Structure 260 5G Core (5GC) 262 User Plane Function (UPF) 263 User Plane Interface 264 Access and Mobility Management Function (AMF) 265 Control Plane Interface 266 Session Management Facility (SMF) 270 Location Management Function (LMF) 272 Secure User Plane Location (SUPL) Location Platform (SLP) 302 User Equipment (UE) 304 Base Station (BS) 306 Network Entity 310 Wireless Wide Area Network (WWAN) Transceiver 312 Receiver 314 Transmitter 316 Antenna 318 Signal 320 Short-Range Wireless Transceiver 322 Receiver 324 Transmitter 326 Antenna 328 signal 330 Satellite Positioning System (SPS) Receiver 332 Processing System 334 Data Bus 336 Antenna 338 Satellite Positioning System (SPS) signals 340 Memory Components 342 RIS module 344 Sensors 346 User Interface 350 Wireless Wide Area Network (WWAN) Transceiver 352 receiver 354 Transmitter 356 Antenna 358 Signal 360 Short Range Wireless Transceiver 362 Receiver 364 Transmitter 366 Antenna 368 signals 370 Satellite Positioning System (SPS) Receiver 376 Antenna 378 Satellite Positioning System (SPS) signals 380 Network Interface 382 Data Bus 384 Processing Systems 386 Memory Components 388 RIS module 390 Network Interface 392 Data Bus 394 Processing Systems 396 Memory Components 398 RIS module 502 Base Station (BS), Serving Base Station 502a, 502b, 502c, 502d, 502e, 502f, 502g, 502h transmit beams 504 User Equipment (UE) 504a, 504b, 504c, 504d receive beams 510 Line of Sight (LOS) Route 512c, 512d, 512e, 512f, 512g Routes 520 Obstacles 600 System 602-1 First base station 602-2 Second base station 604-1 First UE 604-2 Second UE 610 Reconfigurable Intelligent Surface (RIS) 620 Obstacles 700 RIS 710 Flat surface 712 Reflective Elements 714 p-type intrinsic n-type (PIN) diode 716 Bias Wire 720 Controller

Claims

1. 1. A method of operating a user equipment (UE), comprising: receiving location assistance data from a network component, the location assistance data comprising information related to one or more reconfigurable intelligent surfaces (RISs); performing one or more location procedures based on the location assistance data; Equipped with the one or more location procedures are associated with at least one positioning reference signal (RS-P) communicated between the UE and a wireless node via reflections from the one or more RIS; the at least one RS-P comprises at least one downlink or sidelink PRS transmitted by the wireless node; 10. The method of claim 1, wherein the information comprises first quasi-co-location (QCL) information associated with the at least one downlink or sidelink PRS transmitted by the wireless node and second QCL information associated with the at least one RS-P as reflected from the one or more RISs.

2. The method of claim 1 , wherein the information comprises notification of the presence of the one or more RISs in an area.

3. the area corresponds to a cell, or the area is based on a location estimate of the UE, or It is a combination of these, The method of claim 2.

4. wherein said one or more RIS comprises a plurality of RIS; the information comprising a respective RIS identifier for each of the plurality of RISs; The method of claim 2.

5. the one or more location procedures are associated with a UE-based position estimation of the UE; the information comprising a respective location associated with each of the one or more RISs; The method of claim 1.

6. for each of the one or more RISs, the information comprising an indication of whether the respective RIS is a passive RIS or a relay RIS; at least one of the one or more RISs is designated as a relay RIS; The method of claim 1 , wherein the information further comprises, for the at least one RIS, an indication of a gain, a group delay, or a combination thereof, of a RIS reflection.

7. 2. The method of claim 1, wherein a QCL source associated with the first QCL information, the second QCL information, or both corresponds to another RS-P, a signal synchronization block (SSB), or a channel state information reference signal (CSI-RS).

8. the at least one RS-P comprises at least one PRS transmitted by the wireless node; the information comprises one or more PRS search window parameters, the one or more PRS search window parameters comprising an expected reference signal time difference (RSTD) or an expected RSTD uncertainty associated with arrival of the at least one downlink or sidelink PRS at the UE. The method of claim 1.

9. The method of claim 1 , wherein the information comprises an association between the at least one RS-P and the one or more RISs.

10. The one or more location procedures comprise a Downlink Angle of Departure (DL-AoD) positioning session of the UE, the information comprising beam information for each Positioning Reference Signal (PRS) for the one or more RISs, the beam information comprising: PRS identifier and associated RIS identifier, or RIS heading, or Azimuth and altitude of each PRS beam, or the beamwidth of each of said PRS beams; or Boresight direction or beamwidth uncertainty, or the power level of one or more side lobes or back lobes relative to the boresight, or The method of claim 1, including combinations thereof.

11. 1. A method of operating a network element, comprising: determining location assistance data comprising information associated with one or more reconfigurable intelligent surfaces (RISs); transmitting the location assistance data to a user equipment (UE) to facilitate one or more location procedures based on the location assistance data; Equipped with the one or more location procedures are associated with at least one positioning reference signal (RS-P) communicated between the UE and a wireless node via reflections from the one or more RIS; the at least one RS-P comprises at least one downlink or sidelink PRS transmitted by the wireless node; 10. The method of claim 1, wherein the information comprises first quasi-co-location (QCL) information associated with the at least one downlink or sidelink PRS transmitted by the wireless node and second QCL information associated with the at least one RS-P as reflected from the one or more RISs.

12. A user equipment (UE), Memory and at least one transceiver; and at least one processor communicatively coupled to the memory and the at least one transceiver, the at least one processor: receiving location assistance data from a network component via the at least one transceiver, the location assistance data comprising information related to one or more reconfigurable intelligent surfaces (RISs); configured to perform one or more location procedures based on the location assistance data; the one or more location procedures are associated with at least one positioning reference signal (RS-P) communicated between the UE and a wireless node via reflections from the one or more RIS; the at least one RS-P comprises at least one downlink or sidelink PRS transmitted by the wireless node; the information comprising first quasi-co-location (QCL) information associated with the at least one downlink or sidelink PRS transmitted by the wireless node, and second QCL information associated with the at least one RS-P as reflected from the one or more RISs. User Equipment (UE).

13. A UE as described in claim 12, wherein the processor is further configured to execute a method described in any one of claims 2 to 10.

14. 1. A network element comprising: Memory and at least one transceiver; and at least one processor communicatively coupled to the memory and the at least one transceiver, the at least one processor: determining location assistance data comprising information associated with one or more reconfigurable intelligent surfaces (RISs); configured to cause the at least one transceiver to transmit the location assistance data to a user equipment (UE) to facilitate one or more location procedures based on the location assistance data; the one or more location procedures are associated with at least one positioning reference signal (RS-P) communicated between the UE and a wireless node via reflections from the one or more RIS; the at least one RS-P comprises at least one downlink or sidelink PRS transmitted by the wireless node; the information comprising first quasi-co-location (QCL) information associated with the at least one downlink or sidelink PRS transmitted by the wireless node and second QCL information associated with the at least one RS-P as reflected from the one or more RISs. Network components.

15. A non-transitory computer-readable medium having stored thereon computer-executable instructions that, when executed by a processor, cause the processor to perform the method of any one of claims 1 to 11.

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