Reconfigurable intelligent surface assisted positioning

Abstract

Techniques for wireless communications, and in particular, techniques for reconfigurable intelligent surface (RIS) assisted positioning, are disclosed. In some aspects, a base station (BS) can transmit a first positioning reference signal (PRS) to a user equipment (UE). The BS can transmit a second PRS to a RIS configured to reflect received signals to the UE. The BS can receive, from the UE, a downlink reference signal time difference (RSTD) measurement for the first PRS and the second PRS.

Description

[0001] Cross-reference to related applications

[0002] This patent application claims priority to Greek patent application No. 20200100736, filed on December 17, 2020, entitled “RECONFIGURABLE INTELLIGENTSURFACE AIDED POSITIONING”, which has been assigned to the assignee of this application and is hereby expressly incorporated herein by reference in its entirety.

[0003] Public background

[0004] 1. Public domain

[0005] The various aspects of this disclosure generally relate to wireless communications.

[0006] 2. Relevant Technical Descriptions

[0007] Wireless communication systems have undergone several generations of development, including first-generation analog radiotelephone service (1G), second-generation (2G) digital radiotelephone service (including transitional 2.5G and 2.75G networks), third-generation (3G) high-speed data radio service with Internet capabilities, and fourth-generation (4G) service (e.g., Long Term Evolution (LTE) or WiMax). Currently, many different types of wireless communication systems are in use, including cellular and Personal Communication Services (PCS) systems. Known examples of cellular systems include cellular analog Advanced Mobile Phone Systems (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.

[0008] The fifth-generation (5G) wireless standard (known as New Radio (NR)) demands higher data transmission speeds, a greater number of connections, better coverage, and other improvements. According to the Next Generation Mobile Networks Alliance (NGC), the 5G standard is designed to provide tens of megabits per second (Mbps) of data rate to each of tens of thousands of users, and 1 gigabits per second (Gbps) to dozens of employees on an office floor. It should support hundreds of thousands of simultaneous connections to support large-scale sensor deployments. Therefore, 5G mobile communication should have significantly improved spectral efficiency compared to the current 4G standard. Furthermore, signaling efficiency should be improved and latency significantly reduced compared to the current standard. Summary of the Invention

[0009] The following is a simplified overview relating to one or more aspects disclosed herein. Therefore, this overview should not be considered an exhaustive overview relating to all aspects of the conception, nor should it be considered to identify key or decisive elements relating to all aspects of the conception or to depict the scope associated with any particular aspect. Accordingly, the sole purpose of the following overview is to present, in a simplified form, certain concepts relating to one or more aspects of the mechanism disclosed herein before the detailed description given below.

[0010] In some aspects, a wireless communication method performed by a base station includes: transmitting a first positioning reference signal (PRS) to a user equipment (UE), transmitting a second PRS to a reconfigurable smart surface (RIS) configured to reflect the received signal to the UE, and receiving downlink reference signal time difference (RSTD) measurements from the UE for the first PRS and the second PRS.

[0011] In some aspects, a wireless communication method performed by a UE includes: receiving a first PRS from a base station (BS), receiving a second PRS from a RIS configured to reflect the received signal to the UE, and transmitting downlink RSTD measurements for the first and second PRS to the BS.

[0012] In some aspects, a wireless communication method performed by a RIS includes: receiving configuration information for configuring the RIS to reflect a received signal, receiving a PRS or probe reference signal (SRS), and reflecting the PRS or SRS according to the configuration information.

[0013] In some aspects, a BS includes: one or more memories; one or more processors communicatively coupled to the one or more memories, the one or more processors being configured to: transmit a first PRS to a UE; transmit a second PRS to a RIS configured to reflect a received signal back to the UE; and receive downlink RSTD measurements from the UE for the first PRS and the second PRS.

[0014] In some aspects, a UE includes: one or more memories; one or more processors communicatively coupled to the one or more memories, the one or more processors being configured to: receive a first PRS from a BS, receive a second PRS from a RIS configured to reflect the received signal to the UE, and transmit downlink RSTD measurements for the first PRS and the second PRS to the BS.

[0015] In some aspects, a RIS includes: one or more memories; one or more processors communicatively coupled to the one or more memories, the one or more processors being configured to: receive configuration information for configuring the RIS to reflect received signals, receive a PRS or SRS, and reflect the PRS or SRS according to the configuration information.

[0016] In some aspects, a BS includes: means for transmitting a first PRS to a UE; means for transmitting a second PRS to a RIS configured to reflect a received signal to the UE; and means for receiving downlink RSTD measurements from the UE for the first PRS and the second PRS.

[0017] In some aspects, a UE includes: means for receiving a first PRS from a BS, means for receiving a second PRS from a RIS configured to reflect the received signal to the UE, and means for transmitting downlink RSTD measurements for the first PRS and the second PRS to the BS.

[0018] In some aspects, a RIS includes: means for receiving configuration information for configuring the RIS to reflect a received signal; means for receiving a PRS or SRS; and means for reflecting the PRS or SRS according to the configuration information.

[0019] In some aspects, a non-transient computer-readable medium storing an instruction set comprising one or more instructions that, when executed by one or more processors of a BS, cause the base station to: transmit a first PRS to a UE; transmit a second PRS to a RIS configured to reflect received signals back to the UE; and receive downlink RSTD measurements from the UE for the first and second PRS.

[0020] In some aspects, a non-transient computer-readable medium storing an instruction set comprising one or more instructions that, when executed by one or more processors of a UE, cause the UE to: receive a first PRS from a BS, receive a second PRS from a RIS configured to reflect the received signal back to the UE, and transmit downlink RSTD measurements for the first and second PRS to the BS.

[0021] In some aspects, a non-transient computer-readable medium storing an instruction set comprising one or more instructions that, when executed by one or more processors of a RIS, cause the RIS to: receive configuration information for configuring the RIS to reflect received signals, receive a PRS or SRS, and reflect the PRS or SRS according to the configuration information.

[0022] Other objectives and advantages associated with the aspects disclosed herein will be apparent to those skilled in the art based on the accompanying drawings and detailed description. Brief description of the attached diagram

[0024] The accompanying drawings are provided to help describe various aspects of this disclosure, and the drawings are provided for illustrative purposes only and not for limiting the aspects.

[0025] Figure 1 Example wireless communication systems based on various aspects of this disclosure are explained.

[0026] Figure 2A and 2B Example wireless network architectures based on various aspects of this disclosure are explained.

[0027] Figures 3A to 3C It is a simplified block diagram of several sample aspects of components that can be adopted in user equipment (UE), base stations, and network entities and configured to support communications as taught herein.

[0028] Figures 4A to 4D This is a diagram illustrating example frame structures and channels within these frame structures according to various aspects of this disclosure.

[0029] Figure 5 This is a diagram illustrating the communication between an example base station and an example UE according to various aspects of this disclosure.

[0030] Figure 6 An example of positioning based on conventional deep learning time difference of arrival (TDoA) is explained.

[0031] Figure 7 The system describes a reconfigurable smart surface (RIS) for wireless communication based on various uses.

[0032] Figure 8 The system for RIS-assisted RSTD measurement was explained based on several aspects.

[0033] Figures 9 to 11 This is a flowchart of an example process associated with RIS-assisted localization based on some aspects.

[0034] Detailed description

[0035] Various aspects of this disclosure are provided below in the description and accompanying drawings of various examples provided for illustrative purposes. Alternative aspects may be designed without departing from the scope of this disclosure. Furthermore, elements well-known in this disclosure will not be described in detail or will be omitted so as not to obscure the relevant details of this disclosure.

[0036] The terms “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 superior to or better than the others. Similarly, the term “aspects of this disclosure” does not require that all aspects of this disclosure include the features, advantages, or modes of operation discussed.

[0037] Those skilled in the art will appreciate that the information and signals described below can be represented using any of a variety of different techniques and arts. For example, the data, instructions, commands, information, signals, bits, symbols, and chips that may be referred to throughout the following description may be represented by voltage, current, electromagnetic waves, magnetic fields or magnetic particles, optical fields or optical particles, or any combination thereof, depending in part on the specific application, in part on the desired design, in part on the corresponding technology, etc.

[0038] Furthermore, many aspects are described in the form of sequences of actions performed by elements of, for example, computing devices. It will be appreciated that the various actions described herein can be performed by special-purpose circuitry (e.g., application-specific integrated circuits (ASICs)), by program instructions being executed by one or more processors, or by a combination of both. Additionally, the sequences of actions described herein can be considered to be fully embodied in any form of non-transient computer-readable storage medium storing a corresponding set of computer instructions that, upon execution, will cause an associated processor of the device to perform the functions described herein. Thus, various aspects of this disclosure can be embodied in several different forms, all of which are contemplated to fall within the scope of the claimed subject matter. Furthermore, for each aspect described herein, a corresponding form of any such aspect may be described herein as, for example, "logic configured to perform the described actions."

[0039] As used herein, the terms “User Equipment” (UE) and “Base Station” are not intended to be specific to or otherwise limited to any particular Radio Access Technology (RAT) unless otherwise stated. Generally, a UE can be any wireless communication device used by a user to communicate over a wireless communication network (e.g., mobile phone, router, tablet computer, laptop computer, consumer asset tracking device, wearable device (e.g., smartwatch, glasses, augmented reality (AR) / virtual reality (VR) headset, etc.), vehicle (e.g., car, motorcycle, bicycle, etc.), Internet of Things (IoT) device, etc.). A UE can be mobile or can (e.g., at certain times) be stationary and can communicate with a Radio Access Network (RAN). As used herein, the term “UE” can be interchangeably referred to as “Access Terminal” or “AT”, “Client Equipment”, “Wireless Equipment”, “Subscriber Equipment”, “Subscriber Terminal”, “Subscriber Station”, “User Terminal” or “UT”, “Mobile Equipment”, “Mobile Terminal”, “Mobile Station”, or variations thereof. Generally, a UE can communicate with the core network via the RAN, and through the core network, the UE can connect to external networks (such as the Internet) and other UEs. Of course, other mechanisms for connecting to the core network and / or the Internet are also possible for the UE, such as through a wired access network, a wireless local area network (WLAN) (e.g., based on the IEEE 802.11 standard), and so on.

[0040] A base station may operate according to one of several RATs to communicate with a UE, depending on the network in which it is deployed, and may be alternatively referred to as an Access Point (AP), Network Node, B-Node, Evolved B-Node (eNB), Next Generation eNB (ng-eNB), New Radio (NR) B-Node (also referred to as gNB or gNodeB), etc. A base station may primarily be used to support radio access by the UE, including supporting data, voice, and / or signaling connections with the supported UE. In some systems, the base station may provide purely edge node signaling functions, while in others, it may provide additional control and / or network management functions. The communication link through which the UE can signal to the base station is called an uplink (UL) channel (e.g., reverse traffic channel, reverse control channel, access channel, etc.). The communication link through which the base station can signal to the UE is called a downlink (DL) or forward link channel (e.g., paging channel, control channel, broadcast channel, forward traffic channel, etc.). As used herein, the term traffic channel (TCH) may refer to an uplink / reverse traffic channel or a downlink / forward traffic channel.

[0041] The term "base station" can refer to a single physical transmit / receive point (TRP) or multiple physical TRPs that may or may not be located in the same place. For example, when the term "base station" refers to a single physical TRP, the physical TRP may be a base station antenna corresponding to a cell (or several cell sectors) of the base station. When the term "base station" refers to multiple physical TRPs located in the same place, the physical TRP may be an antenna array of the base station (e.g., in a multiple-input multiple-output (MIMO) system or in the case of beamforming at the base station). When the term "base station" refers to multiple physical TRPs not located in the same place, the physical TRP may be a distributed antenna system (DAS) (a network of spatially separated antennas connected to a common source via a transmission medium) or a remote radio headend (RRH) (a remote base station connected to a serving base station). Alternatively, non-co-located physical TRPs may be the serving base station from which the UE receives measurement reports and a neighboring base station from which the UE is measuring its reference RF signal. Since a TRP is the point from which a base station transmits and receives wireless signals, as used herein, references to transmissions from or receptions at a base station should be understood as references to the specific TRP of that base station.

[0042] In some implementations that support UE positioning, the base station may not support the UE's radio access (e.g., it may not support data, voice, and / or signaling connections regarding the UE), but may instead transmit reference signals to the UE for measurement, and / or receive and measure signals transmitted by the UE. Such a base station may be referred to as a positioning tower (e.g., in the case of transmitting signals to the UE) and / or as a location measurement unit (e.g., in the case of receiving and measuring signals from the UE).

[0043] An “RF signal” refers to an electromagnetic wave of a given frequency that transmits information across the 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 individual RF signals through a multipath channel, a receiver may receive multiple “RF signals” corresponding to each transmitted RF signal. The same RF signal transmitted on different paths between the transmitter and receiver can be referred to as a “multipath” RF signal.

[0044] Figure 1An example wireless communication system 100 has been described. The wireless communication system 100 (also referred to as a wireless wide area network (WWAN)) may include individual base stations 102 and individual UEs 104. Base station 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, macrocell base stations may include eNBs and / or ng-eNBs (where wireless communication system 100 corresponds to an LTE network), or gNBs (where wireless communication system 100 corresponds to an NR network), or a combination of both, and small cell base stations may include femtocells, picocells, microcells, etc.

[0045] Each base station 102 can collectively form a RAN and interface with a core network 170 (e.g., an evolved packet core (EPC) or a 5G core (5GC)) via a backhaul link 122, and connect to one or more location servers 172 (which may be part of the core network 170 or external to it) via the core network 170. Among other functions, base stations 102 can also perform functions related to one or more of the following: transmitting user data, radio channel cryptography and decoding, integrity protection, header compression, mobility control functions (e.g., handover, dual connectivity), inter-cell interference coordination, connection establishment and release, load balancing, distribution of non-access stratum (NAS) messages, NAS node selection, synchronization, RAN sharing, multimedia broadcast multicast service (MBMS), subscriber and equipment tracking, RAN information management (RIM), paging, location, and delivery of alarm messages. Base stations 102 can communicate with each other directly or indirectly (e.g., via EPC / 5GC) via a backhaul link 134 (which may be wired or wireless).

[0046] Base station 102 can wirelessly communicate with UE 104. Each base station 102 can provide communication coverage for its respective geographical coverage area 110. In one aspect, one or more cells can be supported by base station 102 in each coverage area 110. A “cell” is a logical communication entity used to communicate with a base station (e.g., on a frequency resource, referred to as a carrier frequency, component carrier, carrier, frequency band, etc.) and can be associated with an identifier (e.g., Physical Cell Identifier (PCI), Virtual Cell Identifier (VCI), Cell Global Identifier (CGI)) to distinguish cells operating via the same or different carrier frequencies. In some cases, different cells can be configured according to different protocol types that can provide access to different types of UEs (e.g., Machine Type Communication (MTC), Narrowband IoT (NB-IoT), Enhanced Mobile Broadband (eMBB), or others). Since cells are supported by specific base stations, the term “cell” can refer to either or both of the logical communication entity and the base station supporting that logical communication entity, depending on the context. In some contexts, the term "cellular" can also refer to the geographical coverage area (e.g., sector) of a base station, in the sense that the carrier frequency can be detected and used for communication within a portion of the geographic coverage area 110.

[0047] While the geographic coverage areas 110 of adjacent macrocell base stations 102 may partially overlap (e.g., in handover areas), some geographic coverage areas 110 may substantially overlap with larger geographic coverage areas 110. For example, a small cell base station 102' may have a coverage area 110' that substantially overlaps with the coverage areas 110 of one or more macrocell base stations 102. A network that includes 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 provide service to a restricted group known as a Closed Subscriber Group (CSG).

[0048] The communication link 120 between base station 102 and UE 104 may include uplink (also known as reverse link) transmission from UE 104 to base station 102 and / or downlink (also known as forward link) transmission from base station 102 to UE 104. The communication link 120 may use MIMO antenna technologies, including spatial multiplexing, beamforming, and / or transmit diversity. The communication link 120 may use one or more carrier frequencies. Carrier allocation may be asymmetric with respect to the downlink and uplink (e.g., more or fewer carriers may be allocated to the downlink compared to the uplink).

[0049] 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 unlicensed spectrum (e.g., 5 GHz). When communicating in unlicensed spectrum, the WLAN STA 152 and / or WLAN AP 150 may perform a clear channel assessment (CCA) or listen-before-speak (LBT) procedure to determine channel availability before communication.

[0050] Small cell base station 102' can operate in licensed and / or unlicensed spectrum. When operating in unlicensed spectrum, small cell base station 102' can employ LTE or NR technology and use the same 5 GHz unlicensed spectrum as used by WLAN AP 150. Small cell base station 102' employing LTE / 5G in unlicensed spectrum can enhance access network coverage and / or increase access network capacity. NR in unlicensed spectrum may be referred to as NR-U. LTE in unlicensed spectrum may be referred to as LTE-U, Licensed Assisted Access (LAA), or MulteFire.

[0051] The wireless communication system 100 may further include a millimeter-wave (mmW) base station 180, which can operate in mmW and / or near-mmW frequencies to communicate with the UE 182. Extremely high frequency (EHF) is a portion of the electromagnetic spectrum that contains radio frequency (RF). EHF has a range of 30 GHz to 300 GHz and wavelengths between 1 mm and 10 mm. Radio waves in this band are referred to as millimeter waves. Near-mmW extends down to a 3 GHz frequency with a 100 mm wavelength. Ultra-high frequency (SHF) bands extend between 3 GHz and 30 GHz, and are also referred to as centimeter waves. Communication using mmW / near-mmW RF bands has high path loss and relatively short range. The mmW base station 180 and the UE 182 can utilize beamforming (transmit and / or receive) on the mmW communication link 184 to compensate for the extremely high path loss and short range. Furthermore, it will be appreciated that in alternative configurations, one or more base stations 102 may also use mmW or near-mmW and beamforming for transmission. Accordingly, it will be understood that the foregoing explanations are merely illustrative and should not be construed as limiting the aspects disclosed herein.

[0052] Transmit beamforming is a technique for focusing RF signals in a specific direction. Conventionally, when a network node (e.g., a base station) broadcasts an RF signal, it broadcasts the signal in all directions (omnidirectionally). Using transmit beamforming, the network node determines where a given target device (e.g., a UE) is located (relative to the transmitting network node) and projects a stronger downlink RF signal in that specific direction, thus providing the receiving device with a faster (in terms of data rate) and stronger RF signal. To change the directivity of the RF signal during transmission, 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 can use an antenna array (referred to as a "phased array" or "antenna array") that generates a beam of RF waves, which can be "guided" to different directions without actually moving the antennas. Specifically, RF currents from the transmitters are fed to the individual antennas with the correct phase relationship so that radio waves from the separate antennas add together in the desired direction to increase radiation, while simultaneously canceling each other out in the undesired direction to suppress radiation.

[0053] Transmit beams can be quasi-co-located, meaning they appear to the receiver (e.g., the UE) with identical parameters, regardless of whether the network node's transmit antennas are physically co-located. In NR, there are four types of quasi-co-location (QCL) relationships. Specifically, a given type of QCL relationship means that certain parameters of the target reference RF signal on the target beam can be derived from information about the source reference RF signal on the 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, average 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 average delay of the target reference RF signal transmitted on the same channel. If the source reference RF signal is of type QCL D, the receiver can use the source reference RF signal to estimate the spatial reception parameters of the target reference RF signal transmitted on the same channel.

[0054] In receive beamforming, a receiver uses a receive beam to amplify an RF signal detected on a given channel. For example, a receiver may increase the gain setting of an antenna array and / or adjust the phase setting of the antenna array in a specific direction to amplify the RF signal received from that direction (e.g., increase its gain level). Thus, when a receiver is referred to as beamforming in a certain direction, it means that the beam gain in that direction is higher than the beam gain in other directions, or that the beam gain in that direction is the highest compared to the beam gain of all other receive beams available to the receiver in that direction. This results in a stronger received signal strength (e.g., Reference Signal Received Power (RSRP), Reference Signal Received Quality (RSRQ), Signal-to-Interference-plus-Noise Ratio (SINR), etc.) of the RF signal received from that direction.

[0055] The receive beam can be spatially dependent. Spatial dependency means that the parameters of the transmit beam used for the second reference signal can be derived from information about the receive beam of the first reference signal. For example, the UE can use a specific receive beam to receive one or more reference downlink reference signals (e.g., Position Reference Signal (PRS), Tracking Reference Signal (TRS), Phase Tracking Reference Signal (PTRS), Cell-Specific Reference Signal (CRS), Channel State Information Reference Signal (CSI-RS), Primary Synchronization Signal (PSS), Secondary Synchronization Signal (SSS), Synchronization Block (SSB), etc.) from the base station. The UE can then form a transmit beam based on the parameters of the receive beam to transmit one or more uplink reference signals (e.g., Uplink Position Reference Signal (UL-PRS), Probe Reference Signal (SRS), Demodulation Reference Signal (DMRS), PTRS, etc.) to the base station.

[0056] Note that, depending on the entity forming the "downlink" beam, the beam can be either a transmit beam or a receive beam. For example, if a base station is forming a downlink beam to transmit a reference signal to a UE, then the downlink beam is a transmit beam. However, if a UE is forming a downlink beam, then the downlink beam is a receive beam for receiving downlink reference signals. Similarly, depending on the entity forming the "uplink" beam, the beam can be either a transmit beam or a receive beam. For example, if a base station is forming an uplink beam, then the uplink beam is an uplink receive beam, while if a UE is forming an uplink beam, then the uplink beam is an uplink transmit beam.

[0057] In 5G, the spectrum in which radio nodes (e.g., base stations 102 / 180, UE 104 / 182) operate is divided into multiple frequency ranges: FR1 (from 450 to 6000 MHz), FR2 (from 24250 to 52600 MHz), FR3 (above 52600 MHz), and FR4 (between FR1 and FR2). In multi-carrier systems (such as 5G), one of the carrier frequencies is referred to as the “primary carrier” or “anchor carrier” or “primary serving cell” or “PCell,” and the remaining carrier frequencies are referred to as “secondary carriers” or “secondary serving cells” or “SCell.” In carrier aggregation, the anchor carrier is the carrier operating on the primary frequency (e.g., FR1) utilized by UE 104 / 182 and on the cell in which UE 104 / 182 performs an initial radio resource control (RRC) connection establishment procedure or initiates an RRC connection re-establishment procedure. The primary carrier carries all shared control channels as well as UE-specific control channels, and can be a carrier on a licensed frequency (however, this is not always the case). The secondary carrier is a carrier operating on a second frequency (e.g., FR2), which can be configured once an RRC connection is established between UE 104 and the anchor carrier, and can be used to provide additional radio resources. In some cases, the secondary carrier can be a carrier on an unlicensed frequency. The secondary carrier may contain only the necessary signaling information and signals; for example, UE-specific signaling information and signals may not be present on the secondary carrier, since both the primary uplink and downlink carriers are typically UE-specific. This means that different UEs 104 / 182 in a cell can have different downlink primary carriers. The same applies to the uplink primary carrier. The network can change the primary carrier of any UE 104 / 182 at any time. For example, this is done to balance the load on different carriers. Since a “serving cell” (whether PCell or SCell) corresponds to the carrier frequency / component carrier that a base station is using for communication, the terms “cell,” “serving cell,” “component carrier,” “carrier frequency,” etc., can be used interchangeably.

[0058] For example, still refer to Figure 1 One of the frequencies utilized by the macrocell base station 102 can be an anchor carrier (or "PCell"), and other frequencies utilized by the macrocell base station 102 and / or mmW base station 180 can be secondary carriers ("SCell"). Simultaneous transmission and / or reception on multiple carriers allows the UE 104 / 182 to significantly increase its data transmission and / or reception rates. For example, two 20MHz aggregated carriers in a multi-carrier system would theoretically result in twice the data rate (i.e., 40MHz) compared to the data rate obtained from a single 20MHz carrier.

[0059] The wireless communication system 100 may further include a UE 164, which can communicate with the macrocell base station 102 on the communication link 120 and / or with the mmW base station 180 on the mmW communication link 184. For example, the macrocell base station 102 may support PCell and one or more SCells for the UE 164, and the mmW base station 180 may support one or more SCells for the UE 164.

[0060] exist Figure 1 In the example, one or more Earth-orbiting Satellite Positioning System (SPS) spacecraft (SV) 112 (e.g., satellites) can be used as any of the explained UEs (for simplicity, in...). Figure 1 A standalone source of location information (shown as a single UE 104). UE 104 may include one or more dedicated SPS receivers specifically designed to receive signal 124 to derive geographic location information from SV 112. The SPS typically includes a transmitter system (e.g., SV 112) positioned such that receivers (e.g., UE 104) can determine their location on or above the earth based at least in part on signals received from the transmitter. Such transmitters typically transmit signals marked with a set number of repeating pseudo-random noise (PN) codes. While transmitters are typically located in SV 112, they may sometimes be located at a terrestrial control station, base station 102, and / or other UE 104.

[0061] The use of SPS signals can be amplified through various satellite-based augmentation systems (SBAS), which may be associated with or otherwise enabled to work with one or more global and / or regional navigation satellite systems. For example, SBAS may include augmentation systems that provide integrity information, differential correction, etc., such as Wide Area Augmentation System (WAAS), European Geostationary Navigation Coverage Service (EGNOS), Multifunctional Satellite Augmentation System (MSAS), GPS-assisted Geographic Augmentation Navigation or GPS and Geographic Augmentation Navigation System (GAGAN), etc. Therefore, 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 may include SPS, SPS-like systems, and / or other signals associated with one or more such SPS.

[0062] The wireless communication system 100 may further include one or more UEs (such as UE 190) that are indirectly connected to one or more communication networks via one or more device-to-device (D2D) peer-to-peer (P2P) links (referred to as “side links”). Figure 1In the example, UE 190 has a D2D P2P link 192 with a UE 104 connected to a base station 102 (e.g., through which UE 190 indirectly obtains cellular connectivity), and a D2D P2P link 194 with a WLANSTA 152 connected to a WLAN AP 150 (through which UE 190 indirectly obtains WLAN-based Internet connectivity). In one example, D2D P2P links 192 and 194 can use any known D2D RAT (such as LTE Direct (LTE-D), WiFi Direct (WiFi-D)). (etc.) to support.

[0063] Figure 2A Example wireless network architecture 200 is explained. For example, 5GC 210 (also referred to as Next Generation Core (NGC)) can be functionally considered as control plane functions 214 (e.g., UE registration, authentication, network access, gateway selection, etc.) and user plane functions 212 (e.g., UE gateway functions, access to data networks, IP routing, etc.), which operate collaboratively to form the core network. User plane interface (NG-U) 213 and control plane interface (NG-C) 215 connect gNB 222 to 5GC 210, specifically to control plane functions 214 and user plane functions 212. In an additional configuration, ng-eNB 224 can also connect to 5GC 210 via NG-C 215 to control plane function 214 and NG-U 213 to user plane function 212. Furthermore, ng-eNB 224 can communicate directly with gNB 222 via backhaul connection 223. In some configurations, the new RAN 220 may have only one or more gNB 222s, while other configurations include both one or more ng-eNB 224s and one or more gNB 222s. The gNB 222 or ng-eNB 224 can be used with UE 204 (e.g., Figure 1 The UE 204 can communicate with any UE depicted herein. Another optional aspect may include a location server 230, which may communicate with the 5GC 210 to provide location assistance to the UE 204. The location server 230 may be implemented as multiple separate servers (e.g., physically separate servers, different software modules on a single server, different software modules extending 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 the UE 204, which can connect to the location server 230 via the core network, the 5GC 210, and / or via the Internet (not described). Furthermore, the location server 230 may be integrated into a component of the core network, or alternatively, may be external to the core network.

[0064] Figure 2B Another example wireless network architecture 250 is described. For example, 5GC 260 can be functionally considered as a control plane function (provided by Access and Mobility Management Function (AMF) 264) and a user plane function (provided by User Plane Function (UPF) 262), which operate cooperatively to form the core network (i.e., 5GC 260). User plane interface 263 and control plane interface 265 connect ng-eNB 224 to 5GC 260, specifically to UPF 262 and AMF 264, respectively. In an additional configuration, gNB 222 can also connect to 5GC 260 via control plane interface 265 to AMF 264 and user plane interface 263 to UPF 262. Furthermore, ng-eNB 224 can communicate directly with gNB 222 via backhaul connection 223, with or without gNB direct connectivity to 5GC 260. In some configurations, the new RAN 220 may have only one or more gNB 222s, while other configurations include both one or more ng-eNB 224s and one or more gNB 222s. The gNB 222 or ng-eNB 224 can be used with UE 204 (e.g., Figure 1 The base station of the new RAN 220 communicates with the AMF 264 via the N2 interface and with the UPF 262 via the N3 interface.

[0065] The functions of AMF 264 include registration management, connection management, reachability management, mobility management, lawful interception, transmission of Session Management (SM) messages between UE 204 and Session Management Function (SMF) 266, transparent proxy service for routing SM messages, access authentication and access authorization, transmission of Short Message Service (SMS) messages between UE 204 and Short Message Service Function (SMSF) (not shown), and Security Anchor Functionality (SEAF). AMF 264 also interacts with Authentication Server Function (AUSF) (not shown) and UE 204, and receives an intermediate key established as a result of the UE 204 authentication process. In the case of authentication based on the UMTS (Universal Mobile Telecommunications System) Subscriber Identity Module (USIM), AMF 264 retrieves security material from the AUSSF. The functions of AMF 264 also include Security Context Management (SCM). The SCM receives a key from the SEAF, which is used by the SCM to derive a key that varies depending on the access network. The functionality of AMF 264 also includes: location service management for regulatory services, transmission of location service messages between UE 204 and Location Management Function (LMF) 270 (which acts as location server 230), transmission of location service messages between the new RAN 220 and LMF 270, allocation of EPS bearer identifiers for interoperability with Evolved Packet Systems (EPS), and UE 204 mobility event notification. Additionally, AMF 264 supports functionality in non-3GPP (3rd Generation Partnership Project) access networks.

[0066] The functions of UPF 262 include: acting as an anchor point for intra / inter-RAT mobility (where applicable), acting as an external Protocol Data Unit (PDU) session point interconnecting to a data network (not shown), providing packet routing and forwarding, packet inspection, user plane policy rule enforcement (e.g., strobing, redirection, traffic steering), lawful interception (user plane collection), traffic usage reporting, quality of service (QoS) handling for user plane (e.g., uplink / downlink rate enforcement, reflective QoS marking in the downlink), uplink traffic verification (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. UPF 262 may also support the transmission of location service messages on the user plane between UE 204 and a location server (such as Secure User Plane Positioning (SUPL) Location Platform (SLP) 272).

[0067] The functions of SMF 266 include session management, UE Internet Protocol (IP) address allocation and management, selection and control of user plane functions, traffic bootstrapping configuration at UPF 262 for routing traffic to the correct destination, partial control of policy enforcement and QoS, and downlink data notification. The interface used by SMF 266 to communicate with AMF 264 is called the N11 interface.

[0068] Another optional aspect may include LMF 270, which can communicate with 5GC 260 to provide location assistance to UE 204. LMF 270 can be implemented as multiple separate servers (e.g., physically separate servers, different software modules on a single server, different software modules extending across multiple physical servers, etc.), or alternatively, each may correspond to a single server. LMF 270 can be configured to support one or more location services for UE 204, which can connect to LMF 270 via the core network, 5GC 260, and / or via the Internet (not explained). SLP 272 supports similar functionality to LMF 270, but while LMF 270 can communicate with AMF 264, the new RAN 220, and UE 204 on the control plane (e.g., using interfaces and protocols designed to convey signaling messages rather than voice or data), SLP 272 can communicate with UE 204 and external clients on the user plane (e.g., using protocols designed to carry voice and / or data, such as Transmission Control Protocol (TCP) and / or IP). Figure 2B (Not shown in the image) communicates.

[0069] Figure 3A , 3B The document describes several example components (represented by corresponding boxes) that can be incorporated into UE 302 (which may correspond to any UE described herein), base station 304 (which may correspond to any base station described herein), and network entity 306 (which may correspond to or embody any network function described herein, including location server 230 and LMF 270) to support file transfer operations as taught herein. It will be appreciated that these components can be implemented in different types of devices (e.g., in ASICs, in system-on-chips (SoCs), etc.) in different implementations. The described components can also be incorporated into other devices in a communication system. For example, other devices in the system may include components similar to those described to provide similar functionality. Furthermore, a given device may include one or more of these 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.

[0070] UE 302 and base station 304 each include wireless wide area network (WWAN) transceivers 310 and 350, respectively, providing means (e.g., means for transmitting, means for receiving, means for measuring, means for tuning, means for suppressing transmission, etc.) for communication via one or more wireless communication networks (not shown) (such as NR networks, LTE networks, GSM networks, etc.). WWAN transceivers 310 and 350 may be connected to one or more antennas 316 and 356, respectively, for communication with other network nodes (such as other UEs, access points, base stations (e.g., eNB, gNB), etc.) on a wireless communication medium of interest (e.g., a time / frequency resource set in a specific spectrum) via at least one designated RAT (e.g., NR, LTE, GSM, etc.). WWAN transceivers 310 and 350 can be configured, according to a specified RAT, in various ways to transmit and encode signals 318 and 358 (e.g., messages, indications, information, etc.), and conversely, to receive and decode signals 318 and 358 (e.g., messages, indications, information, pilots, etc.). Specifically, WWAN transceivers 310 and 350 each include one or more transmitters 314 and 354 for transmitting and encoding signals 318 and 358, respectively, and each includes one or more receivers 312 and 352 for receiving and decoding signals 318 and 358, respectively.

[0071] In at least some cases, UE 302 and base station 304 also include wireless local area network (WLAN) transceivers 320 and 360, respectively. WLAN transceivers 320 and 360 can be connected to one or more antennas 326 and 366, respectively, and provide connectivity via at least one designated RAT (e.g., WiFi, LTE-D, etc.). A means for communicating with other network nodes (such as other UEs, access points, base stations, etc.) over a wireless communication medium of interest (e.g., means for transmitting, means for receiving, means for measuring, means for tuning, means for suppressing transmission, etc.). WLAN transceivers 320 and 360 can be configured, according to a specified RAT, in various ways to transmit and encode signals 328 and 368 (e.g., messages, indications, information, etc.), and conversely, to receive and decode signals 328 and 368 (e.g., messages, indications, information, pilots, etc.). Specifically, WLAN transceivers 320 and 360 each include one or more transmitters 324 and 364 for transmitting and encoding signals 328 and 368, respectively, and each includes one or more receivers 322 and 362 for receiving and decoding signals 328 and 368, respectively.

[0072] A transceiver circuit system including at least one transmitter and at least one receiver may, in some implementations, include integrated devices (e.g., transmitter and receiver circuitry implemented as a single communication device), in some implementations, include separate transmitter and receiver devices, or in other implementations, may be implemented in a different manner. In one aspect, the transmitter may include or be coupled to multiple antennas (e.g., antennas 316, 326, 356, 366), such as an antenna array, which allows the corresponding device to perform transmit "beamforming," as described herein. Similarly, the receiver may include or be coupled to multiple antennas (e.g., antennas 316, 326, 356, 366), such as an antenna array, which allows the corresponding device to perform receive beamforming, as described herein. In another aspect, the transmitter and receiver may share the same multiple antennas (e.g., antennas 316, 326, 356, 366) such that the corresponding device can only receive or transmit at a given time, rather than both simultaneously. The wireless communication equipment of UE 302 and / or base station 304 (e.g., one or both of transceivers 310 and 320 and / or one or both of transceivers 350 and 360) may also include a network eavesdropping module (NLM) for performing various measurements, etc.

[0073] In at least some cases, UE 302 and base station 304 also include Satellite Positioning System (SPS) receivers 330 and 370. SPS receivers 330 and 370 may be connected to one or more antennas 336 and 376, respectively, and may be provided with means for receiving and / or measuring SPS signals 338 and 378, such as Global Positioning System (GPS) signals, Global Navigation Satellite System (GLONASS) signals, Galileo signals, BeiDou signals, Indian Regional Navigation Satellite System (NAVIC), Quasi-Zenith Satellite System (QZSS), etc. SPS receivers 330 and 370 may each include any suitable hardware and / or software for receiving and processing SPS signals 338 and 378. SPS receivers 330 and 370 request information and operation from other systems as appropriate and perform necessary calculations to determine the positioning of UE 302 and base station 304 using measurements obtained by any suitable SPS algorithm.

[0074] Base station 304 and network entity 306 each include at least one network interface 380 and 390, providing means for communicating with other network entities (e.g., means for transmitting, means for receiving, etc.). For example, 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 wired or wireless backhaul connection. In some aspects, network interfaces 380 and 390 may be implemented as transceivers configured to support wired or wireless signal communication. This communication may involve, for example, sending and receiving messages, parameters, and / or other types of information.

[0075] UE 302, base station 304, and network entity 306 also include other components that can be used in conjunction with operations disclosed herein. UE 302 includes a processor circuitry that implements a processing system 332 for providing, for example, functionality related to wireless positioning, and for providing other processing functionality. Base station 304 includes a processing system 384 for providing, for example, functionality related to wireless positioning as disclosed herein, and for providing other processing functionality. Network entity 306 includes a processing system 394 for providing, for example, functionality related to wireless positioning as disclosed herein, and for providing other processing functionality. Processing systems 332, 384, and 394 can therefore 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, for example, one or more general-purpose processors, multi-core processors, ASICs, digital signal processors (DSPs), field-programmable gate arrays (FPGAs), or other programmable logic devices or processing circuitry.

[0076] UE 302, base station 304, and network entity 306 include memory circuitry that implements memory components 340, 386, and 396 (e.g., each including a memory device and which may be referred to as a memory) for maintaining information (e.g., information indicating reserved resources, thresholds, parameters, etc.). Memory components 340, 386, and 396 thus provide means for storage, means for retrieval, means for maintenance, etc. In some cases, UE 302, base station 304, and network entity 306 may include positioning modules 342, 388, and 398, respectively. Positioning modules 342, 388, and 398 may be hardware circuitry as part of or coupled to processing systems 332, 384, and 394, which, when executed, cause UE 302, base station 304, and network entity 306 to perform the functionality described herein. In other respects, positioning modules 342, 388, and 398 may be external to processing systems 332, 384, and 394 (e.g., part of a modem processing system, integrated with another processing system, etc.). Alternatively, positioning modules 342, 388, and 398 may be memory modules stored in memory components 340, 386, and 396, respectively, which, when executed by processing systems 332, 384, and 394 (or a modem processing system, another processing system, etc.), enable UE 302, base station 304, and network entity 306 to perform the functionality described herein. Figure 3A The possible locations of the positioning module 342 are described. The positioning module 342 may be part of the WWAN transceiver 310, memory component 340, processing system 332, or any combination thereof, or it may be a stand-alone component. Figure 3B The possible locations of the positioning module 388 are described. The positioning module 388 may be part of the WWAN transceiver 350, the memory component 386, the processing system 384, or any combination thereof, or it may be a stand-alone component. Figure 3C The possible locations of the positioning module 398 are described. The positioning module 398 may be part of (a) network interface 390, memory component 396, processing system 394, or any combination thereof, or may be a stand-alone component.

[0077] UE 302 may include one or more sensors 344 coupled to processing system 332 to provide means for sensing or detecting motion and / or orientation information independent of motion data derived from signals received by WWAN transceiver 310, WLAN transceiver 320, and / or SPS receiver 330. As an example, sensor 344 may include accelerometers (e.g., microelectromechanical systems (MEMS) devices), gyroscopes, geomagnetic sensors (e.g., compasses), altimeters (e.g., barometric altimeters), and / or any other type of motion detection sensor. Furthermore, sensor 344 may include multiple different types of devices and combine their outputs to provide motion information. For example, sensor 344 may use a combination of multi-axis accelerometers and orientation sensors to provide the ability to calculate positioning in 2D and / or 3D coordinate systems.

[0078] Additionally, UE 302 includes a user interface 346, which provides means for providing instructions to the user (e.g., audible and / or visual instructions) and / or for receiving user input (e.g., when the user actuates a sensing device (such as a keypad, touchscreen, microphone, etc.)). Although not shown, base station 304 and network entity 306 may also include user interfaces.

[0079] Referring more specifically to processing system 384, in the downlink, IP packets from network entity 306 can be provided to processing system 384. Processing system 384 can implement functionality for the RRC layer, Packet Data Convergence Protocol (PDCP) layer, Radio Link Control (RLC) layer, and Media Access Control (MAC) layer. The processing system 384 can provide RRC layer functionality associated with broadcast 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 of UE measurement reports; PDCP layer functionality associated with header compression / decompression, security (cryptography, cryptographic decoding, integrity protection, integrity verification), and handover support functions; RLC layer functionality associated with upper-layer PDU delivery, error correction via 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 associated with mapping between logical channels and transport channels, scheduling information reporting, error correction, priority handling, and logical channel priority ordering.

[0080] Transmitter 354 and receiver 352 implement Layer 1 (L1) functionality associated with various signal processing functions. Layer-1, including the physical (PHY) layer, may include error detection on the transport channel, forward error correction (FEC) decoding / decoding of the transport channel, interleaving, rate matching, mapping to the physical channel, modulation / demodulation of the physical channel, and MIMO antenna processing. Transmitter 354 processes the mapping to the signal constellation based on various modulation schemes (e.g., binary phase shift keying (BPSK), quadrature phase shift keying (QPSK), M-phase shift keying (M-PSK), M-quadrature amplitude modulation (M-QAM)). The decoded and modulated symbols can then be split into parallel streams. Each stream can 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 domains, and subsequently combined using an inverse fast Fourier transform (IFFT) to produce 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 the channel estimator can be used to determine the coding and modulation schemes, as well as for spatial processing. The channel estimates can be derived from reference signals transmitted by UE 302 and / or channel condition feedback. Each spatial stream can then be provided to one or more different antennas 356. Transmitter 354 can use the corresponding spatial stream to modulate an RF carrier for transmission.

[0081] At UE 302, receiver 312 receives signals via its corresponding antenna 316. Receiver 312 recovers the information modulated onto the RF carrier and provides this information to processing system 332. Transmitter 314 and receiver 312 implement Layer 1 functionality associated with various signal processing functions. Receiver 312 can perform spatial processing on this information to recover any spatial stream destined for UE 302. If multiple spatial streams are destined for UE 302, they can be combined by receiver 312 into a single OFDM symbol stream. Receiver 312 then uses a Fast Fourier Transform (FFT) to transform the OFDM symbol stream from the time domain to the frequency domain. The frequency domain signal consists of a separate OFDM symbol stream for each subcarrier of the OFDM signal. Symbols on each subcarrier, along with a reference signal, are recovered and demodulated by determining the signal constellation points most likely to be transmitted by base station 304. These soft decisions can be based on a channel estimate calculated by a channel estimator. These soft decisions are then decoded and deinterleaved to recover the original data and control signals transmitted by base station 304 on the physical channel. These data and control signals are then provided to processing system 332, which implements Layer 3 (L3) and Layer 2 (L2) functionality.

[0082] In the uplink, processing system 332 provides demultiplexing, packet reassembly, cipher decoding, header decompression, and control signal processing between the transport and logical channels to recover IP packets from the core network. Processing system 332 is also responsible for error detection.

[0083] Similar to the functionality described in conjunction with downlink transmissions performed by base station 304, processing system 332 provides RRC layer functionality associated with system information (e.g., MIB, SIB) capture, RRC connectivity, and measurement reporting; PDCP layer functionality associated with header compression / decompression and security (cryptography, cryptographic decoding, integrity protection, integrity verification); RLC layer functionality associated with upper-layer PDU delivery, 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 associated with mapping between logical channels and transport channels, multiplexing MAC SDUs onto transport blocks (TBs), demultiplexing MAC SDUs from TBs, scheduling information reporting, error correction via Hybrid Automatic Repeat Request (HARQ), priority handling, and logical channel priority ordering.

[0084] The channel estimate derived by the channel estimator from the reference signal or feedback transmitted by the base station 304 can be used by the transmitter 314 to select an appropriate coding and modulation scheme and to facilitate spatial processing. The spatial stream generated by the transmitter 314 can be provided to different antennas 316. The transmitter 314 can use the corresponding spatial stream to modulate the RF carrier for transmission.

[0085] Uplink transmissions are processed at base station 304 in a manner similar to that described in conjunction with the receiver function at UE 302. Receiver 352 receives signals via its corresponding antenna 356. Receiver 352 recovers the information modulated onto the RF carrier and provides this information to processing system 384.

[0086] In the uplink, processing system 384 provides demultiplexing, packet reassembly, cipher decoding, header decompression, and control signal processing between the transport and logical channels to recover IP packets from UE 302. IP packets from processing system 384 can then be provided to the core network. Processing system 384 is also responsible for error detection.

[0087] For convenience, UE 302, base station 304 and / or network entity 306 are in Figures 3A to 3C The box is shown as including various components that can be configured according to the various examples described herein. However, it will be understood that the illustrated box may have different functionalities in different designs.

[0088] Various components of UE 302, base station 304 and network entity 306 can communicate with each other on data buses 334, 382 and 392 respectively. Figures 3A-3C Components can be implemented in various ways. In some implementations, Figures 3A-3C The components can be implemented in one or more circuits (for example, such as one or more processors and / or one or more ASICs (which may include one or more processors)). Here, each circuit may use and / or incorporate at least one memory component for storing information or executable code used by that circuit to provide this functionality. For example, some or all of the functionality represented by blocks 310 to 346 may be implemented by the processor and memory components of UE 302 (e.g., by executing appropriate code and / or by appropriately configuring the processor components). Similarly, some or all of the functionality represented by blocks 350 to 388 may be implemented by the processor and memory components of base station 304 (e.g., by executing appropriate code and / or by appropriately configuring the processor components). Furthermore, some or all of the functionality represented by blocks 390 to 398 may be implemented by the processor and memory components of network entity 306 (e.g., by executing appropriate code and / or by appropriately configuring the processor components). For simplicity, various operations, actions, and / or functions are described herein as being performed "by the UE," "by the base station," "by the positioning entity," etc. However, as will be appreciated, such operations, actions, and / or functions may actually be performed by specific 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, positioning modules 342, 388, and 398, etc.

[0089] Various frame structures can be used to support downlink and uplink transmissions between network nodes (e.g., base stations and UEs).

[0090] Figure 4A Figure 400 illustrates an example of a downlink frame structure according to various aspects of this disclosure.

[0091] LTE, and in some cases NR, utilizes OFDM on the downlink and single-carrier frequency division multiplexing (SC-FDM) on the uplink. However, unlike LTE, NR also has the option to use OFDM on the uplink. OFDM and SC-FDM divide the system bandwidth into multiple (K) orthogonal subcarriers, which are often referred to as frequency modulation, frequency slots, etc. Each subcarrier can be modulated with data. Generally, modulation symbols are transmitted in the frequency domain for OFDM and in the time domain for SC-FDM. The spacing between adjacent subcarriers can be fixed, and the total number of subcarriers (K) can depend on the system bandwidth. For example, the subcarrier spacing can be 15 kHz, and the minimum resource allocation (resource block) can be 12 subcarriers (or 180 kHz). Therefore, for system bandwidths of 1.25, 2.5, 5, 10, or 20 MHz, the nominal FFT size can be equal to 128, 256, 512, 1024, or 2048, respectively. The system bandwidth can also be divided into subbands. For example, a subband can cover 1.08MHz (i.e., 6 resource blocks), and for system bandwidths of 1.25, 2.5, 5, 10, or 20MHz, there can be 1, 2, 4, 8, or 16 subbands, respectively.

[0092] LTE supports single-parameter design (subcarrier spacing (SCS), symbol length, etc.). In contrast, NR supports multiple parameter designs (μ), for example, subcarrier spacings of 15kHz (μ=0), 30kHz (μ=1), 60kHz (μ=2), 120kHz (μ=3), and 240kHz (μ=4) or larger can be available. Within each subcarrier spacing, there are 14 symbols per time slot. For a 15kHz SCS (μ=0), there is one time slot per subframe, 10 time slots per frame, a time slot duration of 1 millisecond (ms), a symbol duration of 66.7 microseconds (μs), and a maximum nominal system bandwidth (in MHz) of 4K FFT size is 50. For a 30kHz SCS (μ=1), there are two time slots per subframe, 20 time slots per frame, a time slot duration of 0.5ms, a symbol duration of 33.3μs, and a maximum nominal system bandwidth (in MHz) of 4K FFT size of 100. For a 60kHz SCS (μ=2), there are four time slots per subframe, 40 time slots per frame, a time slot duration of 0.25ms, a symbol duration of 16.7μs, and a maximum nominal system bandwidth (in MHz) of 4K FFT size of 200. For a 120kHz SCS (μ=3), there are eight time slots per subframe, 80 time slots per frame, a time slot duration of 0.125ms, a symbol duration of 8.33μs, and a maximum nominal system bandwidth (in MHz) of 4K FFT size of 400. For a 240kHz SCS (μ=4), there are 16 time slots per subframe and 160 time slots per frame. The time slot duration is 0.0625ms, the symbol duration is 4.17μs, and the maximum nominal system bandwidth (in MHz) with a size of 4KFFT is 800.

[0093] exist Figures 4A to 4D In the example, a 15kHz parameter design is used. Therefore, in the time domain, a 10ms frame is divided into 10 equal-sized subframes, each 1ms in size, and each subframe includes one time slot. Figures 4A to 4D In the diagram, time is represented horizontally (on the X-axis), where time increases from left to right, while frequency is represented vertically (on the Y-axis), where frequency increases (or decreases) from bottom to top.

[0094] A resource grid can be used to represent time slots, each time slot comprising one or more concurrent resource blocks (RBs) (also known as physical RBs (PRBs)) in the frequency domain. The resource grid is further divided into multiple resource elements (REs). An RE corresponds to one symbol length in the time domain and one subcarrier in the frequency domain. Figures 4A to 4DIn the parameter design, for a normal cyclic prefix, the RB can contain 12 consecutive subcarriers in the frequency domain and 7 consecutive symbols in the time domain, for a total of 84 REs. For an extended cyclic prefix, the RB can contain 12 consecutive subcarriers in the frequency domain and 6 consecutive symbols in the time domain, for a total of 72 REs. The number of bits carried by each RE depends on the modulation scheme.

[0095] Some REs carry downlink reference (pilot) signals (DL-RS). DL-RS may include PRS, TRS, PTRS, CRS, CSI-RS, DMRS, PSS, SSS, SSB, etc. Figure 4A The example location of the RE carrying PRS (labeled "R") is explained.

[0096] The set of resource elements (REs) used for PRS transmission is called a "PRS resource". The resource element set can span multiple PRBs in the frequency domain and 'N' (such as one or more) consecutive symbols within a time slot in the time domain. In a given OFDM symbol in the time domain, the PRS resource occupies a consecutive PRB in the frequency domain.

[0097] The transmission of PRS resources within a given PRB has a specific comb tooth size (also known as "comb tooth density"). The comb tooth size 'N' represents the subcarrier spacing (or frequency / frequency modulation spacing) within each symbol of the PRS resource configuration. Specifically, for a comb tooth size 'N', the PRS is transmitted in every Nth subcarrier of a symbol in the PRB. For example, for comb tooth-4, for each symbol of the PRS resource configuration, the RE corresponding to every fourth subcarrier (such as subcarriers 0, 4, 8) is used to transmit the PRS resource. Currently, comb tooth sizes of comb tooth-2, comb tooth-4, comb tooth-6, and comb tooth-12 are supported by DL-PRS. Figure 4A An example PRS resource configuration for comb tooth 6 (which spans 6 symbols) is explained. That is, the position of the shaded RE (marked as "R") indicates the PRS resource configuration for comb tooth 6.

[0098] Currently, DL-PRS resources can span 2, 4, 6, or 12 consecutive symbols within a single time slot using a full-frequency interleaved mode. DL-PRS resources can be configured in any downlink or flexible (FL) symbol configured by a higher layer within a time slot. For all REs of a given DL-PRS resource, there may be a constant energy per resource element (EPRE). The following are the symbol-by-symbol frequency offsets for comb sizes 2, 4, 6, and 12 symbols. 2-symbol comb-2: {0,1}; 4-symbol comb-2: {0,1,0,1}; 6-symbol comb-2: {0,1,0,1,0,1}; 12-symbol comb-2: {0,1,0,1,0,1,0,1,0,1,0,1}; 4-symbol comb-4: {0,2,1,3}; 12-symbol comb-4: { 0,2,1,3,0,2,1,3,0,2,1,3}; 6-code comb-6: {0,3,1,4,2,5}; 12-code comb-6: {0,3,1,4,2,5,0,3,1,4,2,5}; and 12-code comb-12: {0,6,3,9,1,7,4,10,2,8,5,11}.

[0099] A “PRS resource set” is a collection of PRS resources used to transmit PRS signals, where each PRS resource has a PRS resource identifier (ID). Furthermore, PRS resources within a PRS resource set are associated with the same TRP. A PRS resource set is identified by its PRS resource set ID and associated with a specific TRP (identified by its TRP ID). Additionally, PRS resources within a PRS resource set share the same periodicity, a common silent mode configuration, and the same repetition factor (such as “PRS-ResourceRepetitionFactor”) across time slots. Periodicity is the time from the first repetition of a first PRS resource in a first PRS instance to the same first repetition of the same first PRS resource in the next PRS instance. The periodicity can have a length chosen from the following: 2^μ*{4,5,8,10,16,20,32,40,64,80,160,320,640,1280,2560,5120,10240} time slots, where μ=0,1,2,3. The repetition factor can have a length chosen from {1,2,4,6,8,16,32} time slots.

[0100] In a PRS resource set, a PRS resource ID is associated with a single beam (or beam ID) transmitted from a single TRP (where a TRP can transmit one or more beams). That is, each PRS resource in a PRS resource set can be transmitted on a different beam, and thus, a "PRS resource" (or simply a "resource") can also be referred to as a "beam". Note that this does not imply whether the UE is aware of the TRP and beam transmitting the PRS.

[0101] A “PRS instance” or “PRS timing” is an instance of a periodically repeating time window (such as a group of one or more consecutive time slots) in which a PRS is expected to be transmitted. A PRS timing may also be referred to as a “PRS positioning timing,” “PRS positioning instance,” “positioning timing,” “positioning instance,” “positioning repetition,” or simply “timing,” “instance,” or “repetition.”

[0102] A “positioning frequency layer” (also simply “frequency layer”) is a collection of one or more PRS resource sets with identical values ​​for certain parameters across one or more TRPs. Specifically, the collection of PRS resource sets has the same subcarrier spacing and cyclic prefix (CP) type (meaning all parameter designs supported by PDSCH are also supported by PRS), the same point A, the same downlink PRS bandwidth, the same starting PRB (and center frequency), and the same comb size. The point A parameter uses the value of the parameter “ARFCN-ValueNR” (where “ARFCN” stands for “Absolute Radio Channel Number”) and is an identifier / code specifying a pair of physical radio channels used for transmission and reception. The downlink PRS bandwidth can have a granularity of 4 PRBs, with a minimum of 24 PRBs and a maximum of 272 PRBs. Currently, up to four frequency layers have been defined, and up to two PRS resource sets can be configured per frequency layer per TRP.

[0103] The concept of a frequency layer is somewhat similar to that of component carriers and bandwidth portions (BWPs), but the difference is that component carriers and BWPs are used by a single base station (or macrocell base station and small cell base station) to transmit data channels, while a frequency layer is used by several (often three or more) base stations to transmit PRS (Positioning Signals). A UE can indicate the number of frequency layers it can support when sending its positioning capabilities to the network (such as during an LTE Positioning Protocol (LPP) session). For example, a UE can indicate whether it can support one or four positioning frequency layers.

[0104] Figure 4B Figure 430 illustrates an example of a channel within a downlink frame structure according to various aspects of this disclosure. Figure 4BExamples of various channels within the downlink time slot of a radio frame are explained. In NR, the channel bandwidth, or system bandwidth, is divided into multiple BWPs. A BWP is a set of adjacent PRBs selected from a subset of shared RBs designed for a given carrier with given parameters. Generally, a maximum of four BWPs can be specified in both the downlink and uplink. That is, a UE can be configured to have up to four BWPs in the downlink and up to four BWPs in the uplink. Only one BWP (uplink or downlink) can be active at a given time, meaning that the UE can only receive or transmit on one BWP at a time. In the downlink, the bandwidth of each BWP should be equal to or greater than the bandwidth of the SSB, but it may or may not contain an SSB.

[0105] Reference Figure 4B The Primary Synchronization Signal (PSS) is used by the UE to determine subframe / symbol timing and physical layer identity. The Secondary Synchronization Signal (SSS) is used by the UE to determine the physical layer cell identity group number and radio frame timing. Based on the physical layer identity and physical layer cell identity group number, the UE can determine the PCI. Based on the PCI, the UE can determine the location of the aforementioned DL-RS. The Physical Broadcast Channel (PBCH) carrying the MIB can be logically grouped with the PSS and SSS to form the SSB (also known as SS / PBCH). The MIB provides the number of RBs in the downlink system bandwidth and the System Frame Number (SFN). The Physical Downlink Shared Channel (PDSCH) carries user data, broadcast system information (such as System Information Blocks (SIBs)) not transmitted through the PBCH, and paging messages.

[0106] The Physical Downlink Control Channel (PDCCH) carries downlink control information (DCI) within one or more Control Channel Elements (CCEs). Each CCE includes one or more RE Group (REG) bundles (which can span multiple symbols in the time domain). Each REG bundle includes 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 physical resource set used to carry the PDCCH / DCI is called the Control Resource Set (CORESET) in NR. In NR, the PDCCH is confined to a single CORESET and transmitted along with its own DMRS. This enables UE-specific beamforming for the PDCCH.

[0107] exist Figure 4BIn the example, each BWP has one CORESET, and this CORESET spans three symbols in the time domain (although it can be only one or two symbols). Unlike the LTE control channel, which occupies the entire system bandwidth, in NR, the PDCCH channel is localized to a specific region in the frequency domain (i.e., the CORESET). Therefore, Figure 4B The frequency components of the PDCCH shown are interpreted in the frequency domain as fewer than a single BWP. Note that although the interpreted CORESETs are contiguous in the frequency domain, they do not need to be contiguous. Additionally, a CORESET can span fewer than three symbols in the time domain.

[0108] The DCI within the PDCCH carries information about uplink resource allocation (persistent and non-persistent) and a description of the downlink data transmitted to the UE (referred to as uplink grant and downlink grant, respectively). More specifically, the DCI indicates the resources scheduled for downlink data channels (e.g., PDSCH) and uplink data channels (e.g., PUSCH). Multiple (e.g., up to eight) DCIs can be configured in the PDCCH, and these DCIs can have one of several formats. For example, different DCI formats exist for uplink scheduling, downlink scheduling, uplink transmit power control (TPC), etc. The PDCCH can be transmitted by 1, 2, 4, 8, or 16 CCEs to accommodate different DCI payload sizes or coding rates.

[0109] Figure 4C Figure 450 illustrates an example of an uplink frame structure according to various aspects of this disclosure. For example... Figure 4C As explained, some REs (denoted as "R") carry DMRS for channel estimation at the receiver (e.g., a base station, another UE, etc.). The UE may, for example, additionally transmit SRS in the last symbol of the time slot. The SRS may have a comb structure, and the UE may transmit the SRS on one of the comb teeth. Figure 4C In the example, the SRS described is a comb tooth-2 on a symbol. The SRS can be used by the base station to obtain Channel State Information (CSI) for each UE. CSI describes how the RF signal propagates from the UE to the base station and represents the combined effects of scattering, fading, and power attenuation over distance. The system uses SRS for resource scheduling, link adaptation, massive MIMO, beam management, etc.

[0110] Currently, SRS resources with comb tooth sizes of 2, 4, or 8 can span 1, 2, 4, 8, or 12 consecutive symbols within a time slot. The following are the symbol-by-symbol frequency offsets for the currently supported SRS comb tooth patterns. 1-code element comb-2: {0}; 2-code element comb-2: {0,1}; 4-code element comb-2: {0,1,0,1}; 4-code element comb-4: {0,2,1,3}; 8-code element comb-4: {0,2,1,3,0,2,1,3}; 12-code element comb-4: {0,2,1,3,0,2,1,3,0,2,1,3}; 4-code element comb-8: {0,4,2,6}; 8-code element comb-8: {0,4,2,6,1,5,3,7}; and 12-code element comb-8: {0,4,2,6,1,5,3,7,0,4,2,6}.

[0111] The set of resource elements used for SRS transmission is called an "SRS resource" and is identified by the parameter "SRS-ResourceId (SRS-ResourceId)". The resource element set can span multiple PRBs in the frequency domain and N (e.g., one or more) consecutive symbols within a time slot in the time domain. In a given OFDM symbol, an SRS resource occupies a consecutive PRB. An "SRS resource set" is a group of SRS resources used for SRS signal transmission and is identified by the SRS resource set ID ("SRS-ResourceSetId").

[0112] Generally, the UE transmits the SRS so that the receiving base station (serving base station or neighboring base station) can measure the channel quality between the UE and the base station. However, the SRS can also be used as an uplink positioning reference signal for uplink positioning procedures (such as UL-TDOA, multiple RTT, DL-AoA, etc.).

[0113] Several enhancements to the previously defined SRS have been proposed for “SRS for Positioning” (also known as “UL-PRS”), such as new interleaving patterns within SRS resources (other than a single symbol / comb-2), new comb types for SRS, new sequences of SRS, larger sets of SRS resources per component carrier, and larger numbers of SRS resources per component carrier. Additionally, the parameters “SpatialRelationInfo” and “PathLossReference” are configured based on downlink reference signals or SSBs from adjacent TRPs. Furthermore, an SRS resource can be transmitted outside the active BWP, and an SRS resource can span multiple component carriers. Moreover, SRS can be configured in RRC connected states and transmitted only within the active BWP. Furthermore, frequency hopping, repetition factors, single antenna ports, and new SRS lengths (e.g., 8 and 12 symbols) may not be present. It is also possible to have open-loop power control but no closed-loop power control, and to use comb-8 (i.e., SRS transmitted every eighth subcarrier in the same symbol). Finally, the UE can transmit from multiple SRS resources through the same transmit beam for UL-AoA. All of these are features outside the current SRS framework, which is configured via higher-layer RRC signaling (and potentially triggered or activated via MAC control elements (CE) or DCI).

[0114] Figure 4D Figure 470 illustrates an example of a channel within an uplink frame structure according to various aspects of this disclosure. A random access channel (RACH) (also referred to as a physical random access channel (PRACH)) may be configured based on the PRACH within one or more time slots within a frame. The PRACH may include six consecutive RB pairs within a time slot. The PRACH allows the UE to perform initial system access and achieve uplink synchronization. The physical uplink control channel (PUCCH) may be located at the edge of the uplink system bandwidth. The PUCCH carries uplink control information (UCI), such as scheduling requests, CSI reports, channel quality indicators (CQI), precoding matrix indicators (PMI), rank indicators (RI), and HARQ ACK / NACK feedback. The physical uplink shared channel (PUSCH) carries data and may additionally be used to carry buffer status reports (BSR), power clearance reports (PHR), and / or UCI.

[0115] Other wireless communication technologies may have different frame structures and / or different channels. Note that the terms “location reference signal” and “PRS” generally refer to specific reference signals used for positioning in NR and LTE systems. However, as used herein, the terms “location reference signal” and “PRS” can 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, etc., as defined in LTE and NR. Additionally, the terms “location reference signal” and “PRS” can refer to downlink or uplink positioning reference signals, unless otherwise indicated by the context. If further distinction of the type of PRS is required, downlink positioning reference signals may be referred to as “DL-PRS”, while uplink positioning reference signals (e.g., positioning SRS, PTRS) may be referred to as “UL-PRS”. Furthermore, for signals that can be transmitted in both uplink and downlink (e.g., DMRS, PTRS), these signals may be prefixed with “UL” or “DL” to distinguish direction. For example, “UL-DMRS” can be distinguished from “DL-DMRS”.

[0116] Figure 5 This is a diagram 500 illustrating communication between base station (BS) 502 (which may correspond to any base station described herein) and UE 504 (which may correspond to any UE described herein). See also... Figure 5 Base station 502 can transmit beamformed signals to UE 504 on one or more transmit beams 502a, 502b, 502c, 502d, 502e, 502f, 502g, 502h, each of which has a beam identifier that can be used by UE 504 to identify the corresponding beam. When base station 502 uses a single antenna array (e.g., a single TRP / cell) to beamform towards UE 504, base station 502 can perform "beam sweeping" by transmitting a first beam 502a, then beam 502b, etc., until finally transmitting beam 502h. Alternatively, base station 502 can transmit beams 502a–502h in a pattern, such as beam 502a, then beam 502h, then beam 502b, then beam 502g, etc. In the case where base station 502 uses multiple antenna arrays (e.g., multiple TRPs / cells) to beamform toward UE 504, each antenna array can perform beam sweeping of a subset of beams 502a–502h. Alternatively, each beam in beams 502a–502h can correspond to a single antenna or antenna array.

[0117] Figure 5Further explanation is provided regarding the paths 506c, 506d, 506e, 506f, and 506g followed by the beamformed signals transmitted on beams 502c, 502d, 502e, 502f, and 502g, respectively. Each path 506c, 506d, 506e, 506f, and 506g may correspond to a single "multipath," or may include multiple "multipaths" ("multipath" clusters) due to the propagation characteristics of radio frequency (RF) signals through the environment. Note that although only the paths for beams 502c-502g are shown, this is for simplicity, and the signals transmitted on each beam 502a-502h will follow several paths. In the example shown, paths 506c, 506d, 506e, and 506f are straight lines, while path 506g is reflected away from obstacle 508 (e.g., buildings, vehicles, terrain features, etc.).

[0118] UE 504 can receive beamformed signals from base station 502 on one or more receive beams 504a, 502b, 504c, 504d. Note that, for simplicity, Figure 5 The beams described herein refer to either the transmit beam or the receive beam, depending on which of the base station 502 and the UE 504 is transmitting and which is receiving. Therefore, the UE 504 may also transmit beam-shaped signals to the base station 502 on one or more beams 504a–504d, and the base station 502 may receive beam-shaped signals from the UE 504 on one or more beams 502a–502h.

[0119] On one hand, base station 502 and UE 504 can perform beam training to align their transmit and receive beams. For example, depending on environmental conditions and other factors, base station 502 and UE 504 can determine optimal transmit and receive beams as 502d and 504b, or as 502e and 504c, respectively. The direction of the optimal transmit beam for base station 502 can be the same as or different from the direction of the optimal receive beam, and similarly, the direction of the optimal receive beam for UE 504 can be the same as or different from the direction of the optimal transmit beam.

[0120] To execute the DL-AoD positioning procedure, base station 502 can transmit reference signals (e.g., PRS, CRS, TRS, CSI-RS, PSS, SSS, etc.) to UE 504 on one or more of the beams 502a-502h, where each beam has a different transmission angle. The different transmission angles of beams 502a-502h will result in different received signal strengths (e.g., RSRP, RSRQ, SINR, etc.) at UE 504. For transmit beams 502a-502h that are further away from the line-of-sight (LOS) path 510 between base station 502 and UE 504, the received signal strength will be lower than that of transmit beams 502a-502h that are closer to the LOS path 510.

[0121] exist Figure 5 In the example, if base station 502 transmits reference signals to UE 504 on beams 502c, 502d, 502e, 502f, and 502g, then transmit beam 502e is optimally aligned with LOS path 510, while transmit beams 502c, 502d, 502f, and 502g are not. Therefore, beam 502e may have a higher received signal strength at UE 504 than beams 502c, 502d, 502f, and 502g. Note that reference signals transmitted on some beams (e.g., beams 502c and / or 502f) may not reach UE 504, or the energy reaching UE 504 from these beams may be so low that the energy may be undetectable or at least negligible.

[0122] UE 504 may report to base station 502 the received signal strength of each measured transmit beam 502c-502g, and optionally, the associated measurement quality, or alternatively, the identity of the transmit beam with the highest received signal strength. Figure 5 (e.g., beam 502e in the example). Additionally or alternatively, where UE 504 also participates in a round-trip time (RTT) or time difference of arrival (TDOA) positioning session with at least one base station 502 or multiple base stations 502, UE 504 may report received transmission (Rx-Tx) or reference signal time difference (RSTD) measurements (and optionally associated measurement quality) to the serving base station 502 or other positioning entity. In any case, the positioning entity (e.g., base station 502, positioning server, third-party client, UE 504, etc.) may estimate the angle from base station 502 to UE 504 as the AoD of the transmit beam (here, transmit beam 502e) with the highest received signal strength (and, if reported, the strongest channel impulse response and / or earliest ToA) at UE 504.

[0123] Figure 6This section explains a typical example of positioning based on DL (Depth-of-Arrival) Time Difference of Arrival (TDoA). In DL-TDoA, synchronous cells (e.g., Figure 6 The ToA difference between gNB1, gNB2, and gNB3 provides a distance estimate along the hyperbola. Multiple ToA measurements are used for triangulation, for example, four or more cells. Network synchronization errors between gNBs are a major obstacle to high-precision positioning. Potential timing differences τ1, τ2, and τ3 along each hyperbola introduce measurement uncertainty.

[0124] Figure 7 A system 700 for wireless communication using a reconfigurable smart surface (RIS) 702 is described. The RIS is an artificial structure with engineered electromagnetic (EM) properties that can collect wireless signals from a transmitter and passively beam-shape them to a desired receiver. The RIS can be configured to reflect incident waves in a desired direction. Figure 7 In the illustrated example, the first BS 102a controls the RIS 702, but the second BS 102b does not control the RIS 702. The enhanced functionality of the system 700 can provide technical advantages in several scenarios.

[0125] For example, in Figure 7 In this scenario, the first BS 102a is attempting to communicate with the first UE 104a behind an obstacle 704 (e.g., a building, hill, or other obstacle) and therefore cannot receive a beam that is otherwise a LOS beam, i.e., transmit beam 2, from the first BS 102a. In this scenario, the first BS 102a can alternatively use transmit beam 1 to direct the signal towards the RIS 702, which is configured to reflect the incoming transmit beam 1 towards the first UE 104a and the area around the obstacle 704. It should be noted that the first BS 102a can configure the RIS 702 for use by the UE in UL, for example, so that the first UE 104a can use the RIS 702 to bounce UL signals back to the first BS 102a, thereby bypassing the obstacle 704.

[0126] In another scenario, the first BS 102a might be aware of obstacles (such as...) Figure 7 Obstacles 704 in the BS 102a may create blind spots (e.g., geographical areas where signals from BS 102a are attenuated), making it difficult for UEs within these blind spots to detect the signal. In this scenario, BS 102a can bounce signals leaving BS 702 back into the blind spot to provide coverage for devices that may be there (including devices that BS 102a is currently unaware of).

[0127] Another scenario where System 700 offers a technological advantage is one involving low-level (e.g., low-power, low-bandwidth, low-antenna-count, low-baseband-processing-capability) UEs, such as “NR Light” or “NR RedCap” UEs, which may be unable to hear or detect PRS transmitted from a non-serving gNB, especially for gNBs located far from the UE. Similarly, SRS measurements of SRS from low-level UEs by non-serving gNBs may be poor. In some environments, the same problem may exist for non-low-level UEs. Regardless of the reason, when a UE cannot detect a sufficient number of location signals from different TRPs, the use of RIS 702 can provide one or more additional location signals from a single TRP. When multiple location signals are provided by the same TRP, network synchronization error issues between TRPs become irrelevant, and obstacles to high-precision positioning are avoided. An example of this specific scenario is... Figure 8 As shown in the image.

[0128] Figure 8 The system 800 for RIS-assisted RSTD measurement is explained in terms of some aspects. Figure 8 The upper part shows the geographical locations of the entities involved in the example scenario, and Figure 8 The lower part explains the timing of signal transmission and reflection in this example scenario.

[0129] exist Figure 8 In this process, the serving gNB (SgNB) or other type of serving base station sends a set of location reference signals to the target UE. The first PRS 802 points to the first RIS (RIS1), the second PRS 804 points to the second RIS (RIS2), and the third PRS 806 points to the target UE. Figure 8 In the example explained, RIS1 is closer to the UE than RIS2. Now refer to Figure 8 In the lower part of the PRS, the third PRS 806 arrives at the UE first at time ToA (SgNB). The first PRS 802 arrives at RIS1 at time Tprop (SgNB → RIS1), and RIS1 transmits the reflected PRS signal 808, which arrives at the UE at time ToA (RIS1). The second PRS 804 arrives at RIS2 at time Tprop (SgNB → RIS2), and RIS2 transmits the reflected PRS signal 810, which arrives at the UE at time ToA (RIS2). The UE measures the arrival time (Rx) of each of the PRS signals 806, 808, and 810. It provides the UE with the PRS real-time difference (PRTD) between the PRS transmission pairs.

[0130] RSTD is the difference between the time it takes for a reference signal to reach the UE and the time it takes for another reference signal to reach the UE. Therefore, RSTD is the difference between a reference ToA and another reference ToA.

[0131] exist Figure 8 In the example shown, the UE can calculate the value of ToA (=Rx-Tx) for each of the third PRS 806, the reflected PRS signal 808, and the reflected PRS signal 810, namely ToA(SgNB), ToA(RIS1), and ToA(RIS2), as well as the RSTD value for each pair. For example, the UE can use the following formula to calculate the RSTD between SgNB and RIS1:

[0132] RSTD(SgNB,RIS1)

[0133] =ToA(SgNB)–ToA(RIS1)

[0134] =(Rx(SgNB)–Tx(SgNB))–((Rx(RIS1)–Tx(RIS1))

[0135] =Rx(SgNB)–Rx(RIS1)–PRTD+Tprop(SgNBàRIS1)

[0136] in

[0137] Rx(SgNB) is the time when the UE receives PRS 806.

[0138] Rx(RIS1) is the time when the UE receives PRS 808.

[0139] PRTD is the transmission time offset between PRS 806 and PRS 808, and

[0140] Tprop(SgNBàRIS1) is the time it takes for PRS 802 to reach RIS1.

[0141] Please note that the transmission time for each PRS is not required. In this example, the formula will calculate the difference between the time it takes for PRS 806 to reach the UE from SgNB and the time it takes for PRS 808 to reach the UE from RIS1.

[0142] For UE-assisted positioning, the UE can report the RSTD without including the PRTD, and the network will calculate the UE's location based on PRTD data known to the network but unknown to the UE. However, for the UE to perform UE-based positioning (the opposite of UE-assisted positioning), the calculation of the RSTD requires knowledge of the PRTD value. In some aspects, the PRTD value is signaled to the UE via auxiliary data provided by a location server. In some aspects, the UE can use the received PRTD as a "desired RSTD," which can inform the UE where it can search for the PRS. In some aspects, a "PRTD uncertainty" value can be provided to the UE, which the UE can use to assist in selecting its PRS search window. In some aspects, Tprop (SgNBàRIS1) can be estimated using Radio Access Technology (RAT) techniques (e.g., NR-based positioning) or RAT-independent methods (e.g., high-precision PRS or other hybrid positioning methods).

[0143] In some respects, the UE can know the geographical locations of RIS1 and RIS2. In this case, the UE can estimate its own location using the RSTD values ​​of the SgNB, RIS1, and RIS2 pairs via triangulation techniques.

[0144] exist Figure 8 In the illustrated example, the SgNB may have a RIS1 configured to reflect the incoming PRS signal 802 in a desired direction (e.g., via link 812 between the SgNB and RIS1). In some environments, RIS1 may not need to be configured for this purpose, for example, because RIS1 is already properly configured to reflect the incoming PRS signal in the desired direction, because RIS1 cannot be configured by the SgNB but provides a suitable reflected signal anyway, or because RIS1 is configured by an entity other than the SgNB. The same may be true for RIS2, for example, via link 814 between the SgNB and RIS2. The desired direction of the reflected signal can be selected for various reasons, such as to get the signal to a target UE at a known location, to get the signal to a target area (e.g., where the LOS signal from the SgNB is blocked by a known obstacle) regardless of whether the target UE is in that area, for other reasons, or some combination thereof. The SgNB may not know the location of the target UE and may not know whether there are any UEs in the target area. The SgNB relies on the UE to measure the RIS reflected signal.

[0145] The signal received by the RIS from the serving base station can be omnidirectional or beamformed, and the reflected beam generated by the RIS can also be similarly omnidirectional or beamformed. When the RIS receives a signal from the serving base station, it can generate a reflected signal that is wider, narrower, or the same width in the transmission profile. For example, the SgNB can transmit a narrow beamformed PRS to the RIS1, and the RIS1 can reflect a more widely dispersed signal to the UE, such as when the UE's location is not precisely known. Similarly, the RIS1 can reflect a more concentrated signal to the target UE, such as when the UE's location has been estimated with some confidence and a narrower beam will provide a better signal-to-noise ratio to the target UE.

[0146] In some respects, the SgNB can dynamically control the behavior of the RIS under its control during the transmission of multiple PRS signals. For example, in Figure 8 In the described scenario, the SgNB can control RIS2 to disable it when the SgNB is transmitting PRS signal 802 toward RIS1, control RIS1 to disable it when the SgNB is transmitting PRS signal 804 toward RIS2, and control both RIS1 and RIS2 to disable them when the SgNB is transmitting PRS signal 806 directly toward the UE. In this way, when reflection is not desired, the SgNB can reduce or eliminate the possibility that the target UE will receive reflected signals from the RIS, for example, so that the PRS signal 806 does not reflect from RIS1 or RIS2 and reach the target UE. It should be noted that the transmission order of the PRS signals is illustrative and not restrictive: for example, in some respects, the SgNB can transmit the PRS first toward the target UE, then toward RIS2, then toward RIS1, or in any other order. It should also be noted that although... Figure 8 An example using two RIS was explained, but the same concept can be applied to any number of RIS greater than zero.

[0147] Because the aforementioned techniques allow positioning to be performed using only a single SgNB, they are suitable for use by lower-level UEs where measurements of neighboring cells are not desired. Since network synchronization errors are not a problem for single-cell positioning methods (such as those disclosed herein), these methods have the potential to achieve higher accuracy than conventional methods that require measurements of neighboring cells. It should be noted that, in some respects, these techniques can also be used in conjunction with conventional techniques that require measurements of neighboring cells.

[0148] Figure 9 This is a flowchart of an example process 900 associated with RIS-assisted localization, based on some aspects. In some implementations, Figure 9 One or more process frames can be executed by a BS (e.g., BS 102). In some implementations, Figure 9One or more process frames can be executed by another device or a group of devices that are separate from or include the BS. Additionally or alternatively, Figure 9 One or more process frames may be executed by one or more components of device 304, such as processing system 384, memory 386, WWAN transceiver 350, WLAN transceiver 360, and / or network interface 380.

[0149] like Figure 9 As shown, process 900 may include transmitting a first PRS to the UE (block 910). For example, as described above, the BS may transmit a first PRS to the UE.

[0150] like Figure 9 As further shown, process 900 may include transmitting a second PRS to a reconfigurable smart surface (RIS) configured to reflect the received signal to the UE (block 920). For example, as described above, the BS may transmit the second PRS to a reconfigurable smart surface (RIS) configured to reflect the received signal to the UE.

[0151] like Figure 9 As further shown, process 900 may include receiving downlink reference signal time difference (RSTD) measurements for the first PRS and the second PRS from the UE (block 930). For example, as described above, the BS may receive downlink RSTD measurements for the first PRS and the second PRS from the UE. In some aspects, the RSTD measurement is the difference between the ToA for the first PRS and the ToA for the second PRS, which may or may not take into account the transmission time offset between the first PRS and the second PRS.

[0152] Process 900 may include additional implementations, such as any single implementation or any combination of implementations described below and / or in conjunction with one or more other processes described elsewhere in this document.

[0153] In the first implementation, process 900 includes: calculating the estimated location of the UE based on RSTD measurements.

[0154] In the second implementation, either alone or in combination with the first implementation, process 900 includes: receiving the estimated location of the UE from the UE.

[0155] In the third implementation, indicating the transmission time offset between the first PRS and the second PRS, either alone or in combination with one or more of the first and second implementations, includes providing the transmission time offset via explicit signaling, indicating the transmission time offset based on the PRS mapping, or a combination thereof.

[0156] In the fourth implementation, receiving downlink RSTD measurements for the first PRS and the second PRS, either alone or in combination with one or more of the first to third implementations, includes receiving the reception time, arrival time, or a combination thereof for the first PRS and the second PRS.

[0157] In the fifth implementation, either alone or in combination with one or more of the first to fourth implementations, the RIS is configured to reflect the received signal to the UE before transmitting the second PRS.

[0158] In the sixth implementation, either alone or in combination with one or more of the first to fifth implementations, the RIS is configured not to reflect the received signal to the UE before transmitting the first PRS.

[0159] In the seventh implementation, either alone or in combination with one or more of the first to sixth implementations, the transmission time offset between the first PRS and the second PRS is indicated to the UE before receiving the RSTD measurement.

[0160] although Figure 9 The example box for process 900 is shown, but in some implementations, process 900 may include... Figure 9 The boxes depicted in the diagram may be fewer, different, or arranged differently compared to additional boxes. Alternatively, two or more boxes in process 900 may be executed in parallel.

[0161] Figure 10 A flowchart of an example process 1000 associated with RIS-assisted localization. In some implementations, Figure 10 One or more process blocks can be executed by a user equipment (UE) (e.g., UE 104). In some implementations, Figure 10 One or more process frames can be executed by another device or a group of devices separate from or including the UE. Additionally or alternatively, Figure 10 One or more process frames may be executed by one or more components of device 302, such as processing system 332, memory 340, WWAN transceiver 310, WLAN transceiver 320, and / or user interface 346.

[0162] like Figure 10 As shown, process 1000 may include receiving a first PRS from the BS (block 1010). For example, as described above, the UE may receive a first PRS from the BS.

[0163] like Figure 10As further shown, process 1000 may include receiving a second PRS from a RIS configured to reflect a received signal back to the UE (block 1020). For example, as described above, the UE may receive a second PRS from a RIS configured to reflect a received signal back to the UE.

[0164] like Figure 10 As further shown, process 1000 may include transmitting downlink RSTD measurements for the first PRS and the second PRS to the BS (block 1030). For example, as described above, the UE may transmit downlink RSTD measurements for the first PRS and the second PRS to the BS.

[0165] Process 1000 may include additional implementations, such as any single implementation or any combination of implementations described below and / or in conjunction with one or more other processes described elsewhere herein.

[0166] In a first aspect, process 1000 includes: determining the transmission time offset between a first PRS and a second PRS, calculating the estimated location of the UE based on RSTD measurements and the transmission time offset between the first PRS and the second PRS, and transmitting the estimated location of the UE to the BS.

[0167] In the second implementation, determining the transmission time offset between the first PRS and the second PRS, either alone or in conjunction with the first implementation, includes receiving the transmission time offset via explicit signaling, determining the transmission time offset based on the PRS mapping, or a combination thereof.

[0168] In the third implementation, transmitting downlink RSTD measurements for the first PRS and the second PRS, either alone or in combination with one or more of the first and second implementations, includes transmitting the reception time, arrival time, or a combination thereof for the first PRS and the second PRS.

[0169] although Figure 10 An example box of process 1000 is shown, but in some implementations, process 1000 may include... Figure 10 The boxes depicted in the process are compared to additional boxes, fewer boxes, different boxes, or boxes arranged differently. Additionally or alternatively, two or more boxes of process 1000 can be executed in parallel.

[0170] Figure 11 A flowchart of an example process 1100 associated with RIS-assisted localization. In some implementations, Figure 11 One or more process blocks can be executed by a RIS (e.g., RIS 702). In some implementations, Figure 11 One or more process frames can be executed by another device or a group of devices separate from or including the RIS.

[0171] like Figure 11 As shown, process 1100 may include receiving configuration information for configuring the RIS to reflect the received signal (block 1110). For example, as described above, the RIS may receive configuration information for configuring the RIS to reflect the received signal.

[0172] like Figure 11 As further shown, process 1100 may include receiving PRS or SRS from the BS (block 1120). For example, as described above, the RIS may receive PRS from the BS. In some aspects, the RIS may receive SRS from the UE.

[0173] like Figure 11 As further shown, process 1100 may include reflecting PRS or SRS based on configuration information (block 1130). For example, as described above, the RIS may reflect PRS to the target UE based on configuration information. In some aspects, as described above, the RIS may reflect SRS to the target BS based on configuration information.

[0174] Process 1100 may include additional implementations, such as any single implementation or any combination of implementations described below and / or in conjunction with one or more other processes described elsewhere herein.

[0175] In the first implementation, reflecting PRS or SRS according to configuration information includes reflecting PRS or SRS in a specified direction.

[0176] In the second implementation, either alone or in conjunction with the first implementation, reflecting PRS or SRS in a specified direction includes reflecting PRS toward the target UE or reflecting SRS toward the target BS.

[0177] In the third implementation, reflecting the PRS or SRS according to configuration information, either alone or in combination with one or more of the first and second implementations, includes reflecting the PRS or SRS as a beam with a specified beamwidth.

[0178] In the fourth implementation, either alone or in combination with one or more of the first to third implementations, reflecting a PRS or SRS into a beam of a specified beamwidth includes reflecting a PRS or SRS into a beam that is wider than the reflected PRS or SRS, the same width as the reflected PRS or SRS, or narrower than the reflected PRS or SRS.

[0179] In the fifth implementation, the configuration information is received from the BS, either alone or in combination with one or more of the first to fourth implementations.

[0180] although Figure 11An example box of process 1100 is shown, but in some implementations, process 1100 may include... Figure 11 The boxes depicted in the process are compared to additional boxes, fewer boxes, different boxes, or boxes arranged differently. Additionally or alternatively, two or more boxes in process 1100 can be executed in parallel.

[0181] In the detailed description above, it can be seen that different features are grouped together in the examples. This manner of disclosure should not be construed as an intention to have more features than those explicitly mentioned in each clause. Rather, aspects of this disclosure may include fewer features than those of the individual example clauses disclosed. Therefore, the appended clauses should thus be considered as incorporated into this description, where each clause may be a separate example. Although each dependent clause may refer in its respective clause to a specific combination with one of the other clauses, the aspects of that dependent clause are not limited to that specific combination. It will be appreciated that other example clauses may also include combinations of aspects of the dependent clause with the subject matter of any other dependent or independent clause, or any feature combined with other dependent and independent clauses. The aspects disclosed herein expressly include these combinations unless explicitly stated or readily inferred that a particular combination is not intended (e.g., contradictory aspects, such as defining an element as both an electrical insulator and an electrical conductor). Furthermore, it is intended that aspects of a clause may be included in any other independent clause, even if that clause is not directly subordinate to that independent clause.

[0182] Examples of implementations are described in the following numbered clauses:

[0183] Clause 1. A wireless communication method performed by a base station, the method comprising: transmitting a first positioning reference signal (PRS) to a user equipment (UE); transmitting a second PRS to a reconfigurable smart surface (RIS) configured to reflect a received signal to the UE; and receiving downlink reference signal time difference (RSTD) measurements from the UE for the first PRS and the second PRS.

[0184] Clause 2. The method of Clause 1 further includes: calculating the estimated location of the UE based on RSTD measurements.

[0185] Clause 3. The method of any of Clauses 1 to 2 further includes: receiving the estimated location of the UE from the UE.

[0186] Clause 4. The method of any of Clauses 1 to 3 further includes configuring the RIS to reflect the received signal to the UE before transmitting the second PRS.

[0187] Clause 5. The method of Clause 4 further includes configuring the RIS to not reflect the received signal to the UE before transmitting the first PRS.

[0188] Clause 6. The method of any of Clauses 1 to 5 further includes, prior to receiving RSTD measurements, indicating to the UE the transmission time offset between the first PRS and the second PRS.

[0189] Clause 7. The method of Clause 6, wherein indicating the transmission time offset between the first PRS and the second PRS includes providing the transmission time offset via explicit signaling, indicating the transmission time offset based on PRS mapping, or a combination thereof.

[0190] Clause 8. The method of any of Clauses 1 to 7, wherein receiving downlink reference signal time difference (RSTD) measurements for the first PRS and the second PRS includes receiving the reception time, arrival time, or a combination thereof for the first PRS and the second PRS.

[0191] Clause 9. A wireless communication method performed by a user equipment (UE), the method comprising: receiving a first positioning reference signal (PRS) from a base station (BS); receiving a second PRS from a reconfigurable smart surface (RIS) configured to reflect the received signal to the UE; and transmitting downlink reference signal time difference (RSTD) measurements for the first PRS and the second PRS to the BS.

[0192] Clause 10. The method as described in Clause 9 further includes: determining the transmission time offset between the first PRS and the second PRS; calculating the estimated location of the UE based on RSTD measurements and the transmission time offset between the first PRS and the second PRS; and transmitting the estimated location of the UE to the BS.

[0193] Clause 11. The method of Clause 10, wherein determining the transmission time offset between the first PRS and the second PRS includes receiving the transmission time offset via explicit signaling, determining the transmission time offset based on the PRS mapping, or a combination thereof.

[0194] Clause 12. The method of any of Clauses 9 to 11, wherein transmitting downlink reference signal time difference (RSTD) measurements for the first PRS and the second PRS includes transmitting the reception time, arrival time, or a combination thereof for the first PRS and the second PRS.

[0195] Clause 13. A wireless communication method performed by a reconfigurable smart surface (RIS), the method comprising: receiving configuration information for configuring the RIS to reflect a received signal; receiving a positioning reference signal (PRS) or a probe reference signal (SRS); and reflecting the PRS or SRS according to the configuration information.

[0196] Clause 14. The method of Clause 13, wherein reflecting PRS or SRS according to configuration information includes reflecting PRS or SRS in a specified direction.

[0197] Clause 15. The method of Clause 14, wherein reflecting PRS or SRS in a specified direction includes reflecting PRS toward the target user equipment (UE).

[0198] Clause 16. The method of any of Clauses 14 to 15, wherein reflecting PRS or SRS in the specified direction includes reflecting SRS toward the target base station (BS).

[0199] Clause 17. The method of any of Clauses 13 to 16, wherein reflecting the PRS or SRS according to configuration information includes reflecting the PRS or SRS as a beam of a specified beamwidth.

[0200] Clause 18. The method of Clause 17, wherein reflecting a PRS or SRS into a beam of a specified beamwidth includes reflecting a PRS or SRS into a beam that is wider than the PRS or SRS being reflected, the same width as the PRS or SRS being reflected, or narrower than the PRS or SRS being reflected.

[0201] Clause 19. The method of any of Clauses 13 to 18, wherein the configuration information is received from a base station (BS).

[0202] Clause 20. A base station (BS) includes: one or more memories; one or more processors communicatively coupled to the one or more memories, the one or more processors being configured to: cause the BS to transmit a first positioning reference signal (PRS) to a user equipment (UE); cause the BS to transmit a second PRS to a reconfigurable smart surface (RIS) configured to reflect received signals to the UE; and receive downlink reference signal time difference (RSTD) measurements from the UE for the first PRS and the second PRS.

[0203] Clause 21. The BS as in Clause 20, wherein the one or more processors are further configured to: calculate the estimated location of the UE based on RSTD measurements.

[0204] Clause 22. The BS of any of Clauses 20 to 21, wherein the one or more processors are further configured to: receive the estimated location of the UE from the UE.

[0205] Clause 23. The BS of any of Clauses 20 to 22, wherein the one or more processors are further configured to, prior to transmitting the second PRS, configure the RIS to reflect the received signal to the UE.

[0206] Clause 24. The BS as in Clause 23, wherein the one or more processors are further configured to configure the RIS not to reflect the received signal to the UE prior to transmitting the first PRS.

[0207] Clause 25. A BS as in any of Clauses 20 to 24, wherein the one or more processors are further configured to indicate to the UE the transmission time offset between the first PRS and the second PRS before receiving RSTD measurements.

[0208] Clause 26. The BS of Clause 25, wherein when indicating the transmission time offset between the first PRS and the second PRS, the one or more processors are configured to provide the transmission time offset via explicit signaling, indicate the transmission time offset based on the PRS mapping, or a combination thereof.

[0209] Clause 27. The BS of any of Clauses 20 to 26, wherein when receiving downlink reference signal time difference (RSTD) measurements for the first PRS and the second PRS, the one or more processors are configured to receive the reception time, arrival time, or a combination thereof for the first PRS and the second PRS.

[0210] Clause 28. A user equipment (UE) comprising: one or more memories; one or more processors communicatively coupled to the one or more memories, the one or more processors being configured to: receive a first positioning reference signal (PRS) from a base station (BS); receive a second PRS from a reconfigurable smart surface (RIS) configured to reflect the received signal to the UE; and cause the UE to transmit downlink reference signal time difference (RSTD) measurements for the first PRS and the second PRS to the BS.

[0211] Clause 29. The UE as described in Clause 28, wherein the one or more processors are further configured to: determine the transmission time offset between the first PRS and the second PRS; calculate the estimated location of the UE based on the RSTD measurement and the transmission time offset between the first PRS and the second PRS; and transmit the estimated location of the UE to the BS.

[0212] Clause 30. The UE as in Clause 29, wherein when determining the transmission time offset between the first PRS and the second PRS, the one or more processors are configured to receive the transmission time offset via explicit signaling, determine the transmission time offset based on the PRS mapping, or a combination thereof.

[0213] Clause 31. For any UE of Clauses 28 to 30, wherein when transmitting downlink reference signal time difference (RSTD) measurements for the first PRS and the second PRS, the one or more processors are configured to transmit the reception time, arrival time, or a combination thereof for the first PRS and the second PRS.

[0214] Clause 32. A reconfigurable smart surface (RIS) comprising: one or more memories; one or more processors communicatively coupled to the one or more memories, the one or more processors being configured to: receive configuration information for configuring the RIS to reflect received signals; receive a positioning reference signal (PRS) or a probe reference signal (SRS); and cause the RIS to reflect the PRS or SRS according to the configuration information.

[0215] Clause 33. The RIS as in Clause 32, wherein when reflecting the PRS or SRS according to configuration information, the one or more processors are configured to reflect the PRS or SRS in a specified direction.

[0216] Clause 34. The RIS as in Clause 33, wherein when reflecting the PRS or SRS in a specified direction, the one or more processors are configured to reflect the PRS toward the target user equipment (UE).

[0217] Clause 35. The RIS of any of Clauses 33 to 34, wherein when reflecting PRS or SRS in a specified direction, the one or more processors are configured to reflect SRS toward the target base station (BS).

[0218] Clause 36. The RIS of any of Clauses 32 to 35, wherein when reflecting the PRS or SRS according to configuration information, the one or more processors are configured to reflect the PRS or SRS as a beam of a specified beamwidth.

[0219] Clause 37. The RIS of Clause 36, wherein when reflecting a PRS or SRS into a beam of a specified beamwidth, the one or more processors are configured to reflect a PRS or SRS into a beam that is wider than, the same as, or narrower than the PRS or SRS being reflected.

[0220] Clause 38. The RIS of any of Clauses 32 to 37, wherein the configuration information is received from a base station (BS).

[0221] Clause 39. A base station (BS) includes: means for transmitting a first positioning reference signal (PRS) to a user equipment (UE); means for transmitting a second PRS to a reconfigurable smart surface (RIS) configured to reflect a received signal to the UE; and means for receiving downlink reference signal time difference (RSTD) measurements from the UE for the first PRS and the second PRS.

[0222] Clause 40. A user equipment (UE) comprising: means for receiving a first positioning reference signal (PRS) from a base station (BS); means for receiving a second PRS from a reconfigurable smart surface (RIS) configured to reflect the received signal to the UE; and means for transmitting downlink reference signal time difference (RSTD) measurements for the first PRS and the second PRS to the BS.

[0223] Clause 41. A reconfigurable smart surface (RIS) comprising: means for receiving configuration information for configuring the RIS to reflect a received signal; means for receiving a positioning reference signal (PRS) or a probe reference signal (SRS); and means for reflecting the PRS or SRS according to the configuration information.

[0224] Clause 42. A non-transient computer-readable medium storing an instruction set comprising one or more instructions that, when executed by one or more processors of a base station (BS), cause the base station to: transmit a first positioning reference signal (PRS) to a user equipment (UE); transmit a second PRS to a reconfigurable smart surface (RIS) configured to reflect received signals to the UE; and receive downlink reference signal time difference (RSTD) measurements from the UE for the first and second PRS.

[0225] Clause 43. A non-transient computer-readable medium storing a set of instructions, the set of instructions comprising one or more instructions which, when executed by one or more processors of a user equipment (UE), cause the UE to: receive a first positioning reference signal (PRS) from a base station (BS); receive a second PRS from a reconfigurable smart surface (RIS) configured to reflect the received signal to the UE; and transmit downlink reference signal time difference (RSTD) measurements for the first PRS and the second PRS to the BS.

[0226] Clause 44. A non-transient computer-readable medium storing an instruction set comprising one or more instructions that, when executed by one or more processors of a reconfigurable intelligent surface (RIS), cause the RIS to: receive configuration information for configuring the RIS to reflect received signals; receive a positioning reference signal (PRS) or a probe reference signal (SRS); and reflect the PRS or SRS according to the configuration information.

[0227] Clause 39. An apparatus comprising: a memory, a transceiver, and a processor communicatively coupled to the memory and the transceiver, the memory, the transceiver, and the processor being configured to perform a method according to any one of Clauses 1 to 19.

[0228] Clause 40. An apparatus comprising means for performing a method as described in any of Clauses 1 to 19.

[0229] Clause 41. A non-transient computer-readable medium storing computer-executable instructions, including at least one instruction for causing a computer or processor to perform a method as described in any of Clauses 1 to 19.

[0230] Additional aspects include at least the following:

[0231] In one aspect, a wireless communication method performed by a base station includes: transmitting a first positioning reference signal (PRS) to a user equipment (UE), transmitting a second PRS to a reconfigurable smart surface (RIS) configured to reflect the received signal to the UE, and receiving downlink reference signal time difference (RSTD) measurements from the UE for the first PRS and the second PRS.

[0232] In some respects, the method includes calculating the estimated location of the UE based on RSTD measurements.

[0233] In some aspects, the method includes receiving the estimated location of the UE from the UE.

[0234] In some respects, the method includes configuring the RIS to reflect the received signal to the UE before transmitting the second PRS.

[0235] In some respects, the method includes configuring the RIS to not reflect the received signal to the UE before transmitting the first PRS.

[0236] In some aspects, the method includes instructing the UE on the transmission time offset between the first PRS and the second PRS before receiving the RSTD measurement.

[0237] In some respects, indicating the transmission time offset between the first PRS and the second PRS includes providing the transmission time offset via explicit signaling, indicating the transmission time offset based on the PRS mapping, or a combination thereof.

[0238] In some respects, receiving downlink reference signal time difference (RSTD) measurements for the first PRS and the second PRS includes receiving the reception time, arrival time, or a combination thereof for the first PRS and the second PRS.

[0239] In one aspect, a wireless communication method performed by a user equipment (UE) includes: receiving a first positioning reference signal (PRS) from a base station (BS), receiving a second PRS from a reconfigurable smart surface (RIS) configured to reflect the received signal to the UE, and transmitting downlink reference signal time difference (RSTD) measurements for the first PRS and the second PRS to the BS.

[0240] In some aspects, the method includes determining the transmission time offset between a first PRS and a second PRS, calculating the estimated location of the UE based on RSTD measurements and the transmission time offset between the first PRS and the second PRS, and transmitting the estimated location of the UE to the BS.

[0241] In some respects, determining the transmission time offset between the first PRS and the second PRS includes receiving the transmission time offset via explicit signaling, determining the transmission time offset based on the PRS mapping, or a combination thereof.

[0242] In some respects, transmitting downlink reference signal time difference (RSTD) measurements for the first PRS and the second PRS includes transmitting the reception time, arrival time, or a combination thereof for the first PRS and the second PRS.

[0243] In one aspect, a wireless communication method performed by a reconfigurable smart surface (RIS) includes: receiving configuration information for configuring the RIS to reflect a received signal, receiving a positioning reference signal (PRS) or a probe reference signal (SRS), and reflecting the PRS or SRS according to the configuration information.

[0244] In some aspects, reflecting PRS or SRS based on configuration information includes reflecting PRS or SRS in a specified direction.

[0245] In some respects, reflecting PRS or SRS in a specified direction includes reflecting PRS toward the target user equipment (UE).

[0246] In some respects, reflecting PRS or SRS in a specified direction includes reflecting SRS toward the target base station (BS).

[0247] In some respects, reflecting a PRS or SRS based on configuration information includes reflecting the PRS or SRS as a beam with a specified beamwidth.

[0248] In some respects, reflecting a PRS or SRS into a beam of a specified beamwidth includes reflecting a PRS or SRS into a beam that is wider than the PRS or SRS being reflected, the same width as the PRS or SRS being reflected, or narrower than the PRS or SRS being reflected.

[0249] In some aspects, this configuration information is received from a base station (BS). In one aspect, a base station (BS) includes: one or more memories; one or more processors communicatively coupled to the one or more memories, the one or more processors being configured to: cause the BS to transmit a first positioning reference signal (PRS) to a user equipment (UE), cause the BS to transmit a second PRS to a reconfigurable smart surface (RIS) configured to reflect received signals to the UE, and receive downlink reference signal time difference (RSTD) measurements from the UE for the first PRS and the second PRS.

[0250] In some respects, the one or more processors are further configured to calculate the estimated location of the UE based on RSTD measurements.

[0251] In some respects, the one or more processors are further configured to receive the estimated location of the UE from the UE.

[0252] In some respects, the one or more processors are further configured to, prior to transmitting the second PRS, configure the RIS to reflect the received signal to the UE.

[0253] In some respects, the one or more processors are further configured to configure the RIS not to reflect the received signal to the UE before transmitting the first PRS.

[0254] In some respects, the one or more processors are further configured to indicate to the UE the transmission time offset between the first PRS and the second PRS before receiving the RSTD measurement.

[0255] In some respects, when indicating the transmission time offset between the first PRS and the second PRS, the one or more processors are configured to provide the transmission time offset via explicit signaling, indicate the transmission time offset based on the PRS mapping, or a combination thereof.

[0256] In some respects, when receiving downlink reference signal time difference (RSTD) measurements for a first PRS and a second PRS, the one or more processors are configured to receive the reception time, arrival time, or a combination thereof for the first PRS and the second PRS.

[0257] In one aspect, a user equipment (UE) includes: one or more memories; one or more processors communicatively coupled to the one or more memories, the one or more processors being configured to: receive a first positioning reference signal (PRS) from a base station (BS), receive a second PRS from a reconfigurable smart surface (RIS) configured to reflect the received signal to the UE, and cause the UE to transmit downlink reference signal time difference (RSTD) measurements for the first PRS and the second PRS to the BS.

[0258] In some aspects, the one or more processors are further configured to: determine the transmission time offset between the first PRS and the second PRS, calculate the estimated location of the UE based on the RSTD measurement and the transmission time offset between the first PRS and the second PRS, and transmit the estimated location of the UE to the BS.

[0259] In some respects, when determining the transmission time offset between the first PRS and the second PRS, the one or more processors are configured to receive the transmission time offset via explicit signaling, determine the transmission time offset based on the PRS mapping, or a combination thereof.

[0260] In some respects, when transmitting downlink reference signal time difference (RSTD) measurements for the first PRS and the second PRS, the one or more processors are configured to transmit the reception time, arrival time, or a combination thereof for the first PRS and the second PRS.

[0261] In one aspect, a reconfigurable smart surface (RIS) includes: one or more memories; one or more processors communicatively coupled to the one or more memories, the one or more processors being configured to: receive configuration information for configuring the RIS to reflect received signals, receive a positioning reference signal (PRS) or a probe reference signal (SRS), and cause the RIS to reflect the PRS or SRS according to the configuration information.

[0262] In some respects, when reflecting PRS or SRS according to configuration information, the one or more processors are configured to reflect PRS or SRS in a specified direction.

[0263] In some respects, when reflecting PRS or SRS in a specified direction, the one or more processors are configured to reflect PRS toward the target user equipment (UE).

[0264] In some respects, when reflecting PRS or SRS in a specified direction, the one or more processors are configured to reflect SRS toward the target base station (BS).

[0265] In some respects, when reflecting a PRS or SRS according to configuration information, the one or more processors are configured to reflect the PRS or SRS as a beam of a specified beamwidth.

[0266] In some respects, when reflecting a PRS or SRS into a beam of a specified beamwidth, the one or more processors are configured to reflect the PRS or SRS into a beam that is wider than the PRS or SRS being reflected, the same width as the PRS or SRS being reflected, or narrower than the PRS or SRS being reflected.

[0267] In some respects, this configuration information is received from the base station (BS).

[0268] In one aspect, a base station (BS) includes: means for transmitting a first positioning reference signal (PRS) to a user equipment (UE); means for transmitting a second PRS to a reconfigurable smart surface (RIS) configured to reflect the received signal to the UE; and means for receiving downlink reference signal time difference (RSTD) measurements from the UE for the first PRS and the second PRS.

[0269] In one aspect, a user equipment (UE) includes: means for receiving a first positioning reference signal (PRS) from a base station (BS); means for receiving a second PRS from a reconfigurable smart surface (RIS) configured to reflect the received signal to the UE; and means for transmitting downlink reference signal time difference (RSTD) measurements for the first PRS and the second PRS to the BS.

[0270] In one aspect, a reconfigurable smart surface (RIS) includes: means for receiving configuration information for configuring the RIS to reflect received signals; means for receiving a positioning reference signal (PRS) or a probe reference signal (SRS); and means for reflecting the PRS or SRS according to the configuration information.

[0271] In one aspect, a non-transient computer-readable medium storing an instruction set comprising one or more instructions that, when executed by one or more processors of a base station (BS), cause the base station to: transmit a first positioning reference signal (PRS) to a user equipment (UE); transmit a second PRS to a reconfigurable smart surface (RIS) configured to reflect received signals to the UE; and receive downlink reference signal time difference (RSTD) measurements from the UE for the first and second PRS.

[0272] In one aspect, a non-transient computer-readable medium storing an instruction set comprising one or more instructions that, when executed by one or more processors of a user equipment (UE), cause the UE to: receive a first positioning reference signal (PRS) from a base station (BS), receive a second PRS from a reconfigurable smart surface (RIS) configured to reflect the received signal back to the UE, and transmit downlink reference signal time difference (RSTD) measurements for the first and second PRS to the BS.

[0273] In one aspect, a non-transient computer-readable medium storing an instruction set comprising one or more instructions that, when executed by one or more processors of a reconfigurable smart surface (RIS), cause the RIS to: receive configuration information for configuring the RIS to reflect received signals, receive a positioning reference signal (PRS) or a probe reference signal (SRS), and reflect the PRS or SRS according to the configuration information.

[0274] Those skilled in the art will appreciate that information and signals can be represented using any of a variety of different techniques and skills. For example, data, instructions, commands, information, signals, bits, symbols, and chips that may be referred to throughout the above description can be represented by voltage, current, electromagnetic waves, magnetic fields or magnetic particles, light fields or light particles, or any combination thereof.

[0275] Furthermore, those skilled in the art will appreciate that the various illustrative logic blocks, modules, circuits, and algorithmic steps described in connection with the aspects disclosed herein can be implemented as electronic hardware, computer software, or a combination of both. To clearly illustrate this interchangeability between hardware and software, the various illustrative components, blocks, modules, circuits, and steps are described above in a generalized manner in terms of their functionality. Whether such functionality is implemented as hardware or software depends on the specific application and the design constraints imposed on the overall system. Those skilled in the art may implement the described functionality in different ways for each specific application, but such implementation decisions should not be construed as departing from the scope of this disclosure.

[0276] The various illustrative logic blocks, modules, and circuits described in conjunction with the aspects disclosed herein can be implemented or executed using a general-purpose processor, DSP, ASIC, 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. The general-purpose processor may be a microprocessor, but in alternatives, it may be any conventional processor, controller, microcontroller, or state machine. The processor can also be implemented as a combination of computing devices, such as a combination of a DSP and a microprocessor, multiple microprocessors, one or more microprocessors cooperating with a DSP core, or any other such configuration.

[0277] The methods, sequences, and / or algorithms described in conjunction with the aspects disclosed herein may be embodied directly in hardware, in a software module executed by a processor, or in a combination of both. The software module may reside in random access memory (RAM), flash memory, read-only memory (ROM), erasable programmable ROM (EPROM), electrically erasable programmable ROM (EEPROM), registers, hard disks, removable disks, CD-ROMs, or any other form of storage medium known in the art. Example storage media are coupled to a processor so that the processor can read and write information from / to the storage medium. In alternatives, the storage medium may be integrated into the processor. The processor and storage medium may reside in an ASIC. The ASIC may reside in a user terminal (e.g., a UE). In alternatives, the processor and storage medium may reside as discrete components in the user terminal.

[0278] In one or more examples, the described functionality may be implemented in hardware, software, firmware, or any combination thereof. If implemented in software, the functionality may be stored or transmitted as one or more instructions or codes on or through a computer-readable medium. A computer-readable medium includes both computer storage media and communication media, including any medium that facilitates the transfer of a computer program from one location to another. A storage medium may be any available medium accessible to a computer. By way of example and not limitation, such computer-readable media may include RAM, ROM, EEPROM, CD-ROM or other optical disc storage, 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 is accessible to a computer. Similarly, any connection is also legitimately referred to as a computer-readable medium. For example, if the 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, then such coaxial cable, fiber optic cable, twisted pair, DSL, or wireless technologies such as infrared, radio, and microwave are included in the definition of medium. As used in this article, disks and discs include compact discs (CDs), laser discs, optical discs, digital multi-purpose discs (DVDs), floppy disks, and Blu-ray discs. Disks typically reproduce data magnetically, while discs reproduce data optically using lasers. Combinations of these should also be included within the scope of computer-readable media.

[0279] While the foregoing disclosure has illustrated illustrative aspects of this disclosure, it should be noted that various changes and modifications may be made therein without departing from the scope of this disclosure as defined by the appended claims. The functions, steps, and / or actions in the method claims according to the aspects of this disclosure described herein need not be performed in any particular order. Furthermore, although elements of this disclosure may be described or claimed in the singular, pluralism is also contemplated unless explicitly stated to be limited to the singular.

Claims

1. A wireless communication method performed by a network node, the method comprising: Transmit the first positioning reference signal (PRS) to the user equipment (UE); The second PRS is transmitted to the reconfigurable smart surface RIS configured to reflect the received signal to the UE; as well as The UE receives downlink reference signal time difference (RSTD) measurements for the first PRS and the second PRS, wherein, before receiving the RSTD measurements, the UE is indicated with a transmission time offset between the first PRS and the second PRS, wherein the transmission time offset is used to calculate the estimated position of the UE.

2. The method of claim 1, further comprising calculating the estimated location of the UE based on the RSTD measurement.

3. The method of claim 1, further comprising receiving the estimated location of the UE from the UE.

4. The method of claim 1, further comprising configuring the RIS to reflect the received signal to the UE before transmitting the second PRS.

5. The method of claim 4, further comprising configuring the RIS to not reflect the received signal to the UE before transmitting the first PRS.

6. The method of claim 1, wherein indicating the transmission time offset between the first PRS and the second PRS comprises providing the transmission time offset via explicit signaling, indicating the transmission time offset based on a PRS mapping, or a combination thereof.

7. The method of claim 1, wherein receiving the downlink reference signal time difference (RSTD) measurement for the first PRS and the second PRS includes receiving the reception time, arrival time, or a combination thereof for the first PRS and the second PRS.

8. A wireless communication method performed by a user equipment (UE), the method comprising: Receive the first positioning reference signal (PRS) from the network node; The second PRS is received from the reconfigurable smart surface RIS configured to reflect the received signal back to the UE; Transmit downlink reference signal time difference (RSTD) measurements for the first PRS and the second PRS to the network node; Determine the transmission time offset between the first PRS and the second PRS; The estimated location of the UE is calculated based on the RSTD measurement and the transmission time offset; as well as The estimated location of the UE is transmitted to the network node.

9. The method of claim 8, wherein determining the transmission time offset between the first PRS and the second PRS comprises receiving the transmission time offset via explicit signaling, determining the transmission time offset based on a PRS mapping, or a combination thereof.

10. The method of claim 8, wherein transmitting the downlink reference signal time difference (RSTD) measurement for the first PRS and the second PRS includes transmitting the reception time, arrival time, or a combination thereof for the first PRS and the second PRS.

11. A wireless communication method performed by a reconfigurable smart surface (RIS), the method comprising: Receive configuration information for configuring the RIS to reflect the received signal; Receive positioning reference signal (PRS) or detection reference signal (SRS); as well as The PRS or SRS is reflected according to the configuration information, wherein, when received, the PRS is a second PRS transmitted from the network node to the RIS for measuring the downlink reference signal time difference (RSTD) with a first PRS transmitted from the network node to the user equipment (UE), wherein the transmission time offset between the first PRS and the second PRS is indicated by the network node for calculating the estimated location of the UE.

12. The method of claim 11, wherein reflecting the PRS or SRS according to the configuration information includes reflecting the PRS or SRS in a specified direction.

13. The method of claim 12, wherein reflecting the PRS or SRS in the designated direction includes reflecting the PRS toward the target user equipment (UE).

14. The method of claim 12, wherein reflecting the PRS or SRS in the designated direction includes reflecting the SRS toward the target network node.

15. The method of claim 11, wherein reflecting the PRS or SRS according to the configuration information includes reflecting the PRS or SRS as a beam with a specified beamwidth.

16. The method of claim 15, wherein reflecting the PRS or SRS into a beam of a specified beamwidth comprises reflecting the PRS or SRS into a beam that is wider than the PRS or SRS being reflected, has the same width as the PRS or SRS being reflected, or is narrower than the PRS or SRS being reflected.

17. The method of claim 11, wherein the configuration information is received from a network node.

18. A network node, comprising: One or more memory units; One or more processors communicatively coupled to the one or more memories, the one or more processors being configured to: This enables the network node to transmit a first positioning reference signal (PRS) to the user equipment (UE). This causes the network node to transmit a second PRS to the reconfigurable smart surface RIS, which is configured to reflect the received signal to the UE. as well as The UE receives downlink reference signal time difference (RSTD) measurements for the first PRS and the second PRS, wherein one or more processors are further configured to indicate to the UE a transmission time offset between the first PRS and the second PRS before receiving the RSTD measurements, wherein the transmission time offset is used to calculate the estimated location of the UE.

19. The network node of claim 18, wherein the one or more processors are further configured to calculate the estimated location of the UE based on the RSTD measurement.

20. The network node of claim 18, wherein the one or more processors are further configured to receive the estimated location of the UE from the UE.

21. The network node of claim 18, wherein the one or more processors are further configured to, prior to transmitting the second PRS, configure the RIS to reflect the received signal to the UE.

22. The network node of claim 21, wherein the one or more processors are further configured to configure the RIS not to reflect the received signal to the UE before transmitting the first PRS.

23. The network node of claim 18, wherein when indicating a transmission time offset between the first PRS and the second PRS, the one or more processors are configured to provide the transmission time offset via explicit signaling, indicate the transmission time offset based on a PRS mapping, or a combination thereof.

24. The network node of claim 18, wherein when receiving the downlink reference signal time difference (RSTD) measurement for the first PRS and the second PRS, the one or more processors are configured to receive the reception time, arrival time, or a combination thereof for the first PRS and the second PRS.

25. A user equipment (UE), comprising: One or more memory units; One or more processors communicatively coupled to the one or more memories, the one or more processors being configured to: Receive the first positioning reference signal (PRS) from the network node; The second PRS is received from the reconfigurable smart surface RIS configured to reflect the received signal back to the UE; This enables the UE to transmit downlink reference signal time difference (RSTD) measurements for the first PRS and the second PRS to the network node; Determine the transmission time offset between the first PRS and the second PRS; The estimated location of the UE is calculated based on the RSTD measurement and the transmission time offset; as well as The estimated location of the UE is transmitted to the network node.

26. The UE of claim 25, wherein when determining the transmission time offset between the first PRS and the second PRS, the one or more processors are configured to receive the transmission time offset via explicit signaling, determine the transmission time offset based on the PRS mapping, or a combination thereof.

27. The UE of claim 25, wherein when transmitting the downlink reference signal time difference (RSTD) measurement for the first PRS and the second PRS, the one or more processors are configured to transmit the reception time, arrival time, or a combination thereof for the first PRS and the second PRS.

28. A reconfigurable smart surface RIS, comprising: One or more memory units; One or more processors communicatively coupled to the one or more memories, the one or more processors being configured to: Receive configuration information for configuring the RIS to reflect the received signal; Receive positioning reference signal (PRS) or detection reference signal (SRS); as well as The RIS reflects the PRS or SRS according to the configuration information, wherein, when received, the PRS is a second PRS transmitted from the network node to the RIS, used to perform downlink reference signal time difference (RSTD) measurement with a first PRS transmitted from the network node to the user equipment (UE), wherein the transmission time offset between the first PRS and the second PRS is indicated by the network node for calculating the estimated location of the UE.

29. The RIS of claim 28, wherein when reflecting the PRS or SRS according to the configuration information, the one or more processors are configured to reflect the PRS or SRS in a specified direction.

30. The RIS of claim 29, wherein when the PRS or SRS is reflected in the designated direction, the one or more processors are configured to reflect the PRS toward the target user equipment (UE).

31. The RIS of claim 29, wherein when the PRS or SRS is reflected in the designated direction, the one or more processors are configured to reflect the SRS toward the target network node.

32. The RIS of claim 28, wherein when reflecting the PRS or SRS according to the configuration information, the one or more processors are configured to reflect the PRS or SRS as a beam of a specified beamwidth.

33. The RIS of claim 32, wherein when the PRS or SRS is reflected as a beam of a specified beamwidth, the one or more processors are configured to reflect the PRS or SRS as a beam that is wider than the PRS or SRS being reflected, the same width as the PRS or SRS being reflected, or narrower than the PRS or SRS being reflected.

34. The RIS of claim 28, wherein the configuration information is received from a network node.

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