Beam adaptation for reconfigurable smart surface assisted UE positioning

Abstract

Aspects presented herein may improve performance and accuracy of RIS-based UE positioning, such as when the RIS has a limited number of sets of available control voltages. In one aspect, a UE obtains an indication of beam pattern information for a set of DL beams for a network entity, where the set of DL beams is associated with an RIS. The UE adjusts a first transmit angle of a set of UL beams based on the beam pattern information and measurements for the set of DL beams, wherein the first transmit angle of the set of UL beams is adjusted to approximately align with a second transmit angle of the set of DL beams from the RIS. The UE transmits the UL beam set to the network entity via the RIS based on the adjusted first transmit angle.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims the benefit of U.S. patent application serial number 17 / 813,456, filed on July 19, 2022, entitled “BEAM ADAPTATION FOR RECONFIGURABLE INTELLIGENT SURFACE AIDED UE POSITIONING,” which is expressly incorporated herein by reference in its entirety. Technical Field

[0003] The present disclosure relates generally to positioning systems, and more particularly to positioning systems related to reconfigurable smart surfaces (RIS). Background Art

[0004] Wireless communication systems are widely deployed to provide a variety of telecommunication services, such as telephony, video, data, messaging, and broadcast. Typical wireless communication systems may employ multiple access technologies capable of supporting communication with multiple users by sharing available system resources. Examples of such multiple access technologies include code division multiple access (CDMA) systems, time division multiple access (TDMA) systems, frequency division multiple access (FDMA) systems, orthogonal frequency division multiple access (OFDMA) systems, single carrier frequency division multiple access (SC-FDMA) systems, and time division synchronous code division multiple access (TD-SCDMA) systems.

[0005] These multiple access technologies have been adopted in various telecommunication standards to provide a common protocol that enables different wireless devices to communicate at a city, country, region, and even global level. An example telecommunication standard is 5G New Radio (NR). 5G NR is part of the continuous mobile broadband evolution promulgated by the Third Generation Partnership Project (3GPP) to meet new requirements associated with latency, reliability, security, scalability (e.g., with the Internet of Things (IoT)) and other requirements. 5GNR includes services associated with enhanced mobile broadband (eMBB), massive machine type communication (mMTC), and ultra-reliable low latency communication (URLLC). Certain aspects of 5G NR may be based on 4G Long Term Evolution (LTE) standards. It is necessary to further improve 5G NR technology. In addition, these improvements may also be applicable to other multiple access technologies and telecommunication standards that employ these technologies. Summary of the invention

[0006] A simplified summary of one or more aspects is presented below to provide a basic understanding of these aspects. This summary is not an extensive review of all contemplated aspects. This summary neither identifies the key or important elements of all aspects, nor describes the scope of any or all aspects. Its sole purpose is to present some concepts of one or more aspects in a simplified form as a prelude to a more detailed description presented later.

[0007] In one aspect of the present disclosure, a method, a computer-readable medium, and an apparatus are provided. The apparatus obtains an indication of beam pattern information for a downlink (DL) beam set for a network entity, wherein the DL beam set is associated with a reconfigurable smart surface (RIS). The apparatus adjusts a first transmit angle of an uplink (UL) beam set based on the beam pattern information and measurements for the DL beam set, wherein the first transmit angle of the UL beam set is adjusted to be approximately aligned with a second transmit angle of the DL beam set from the RIS. Based on the adjusted first transmit angle, the UL beam set is transmitted to the network entity via the RIS.

[0008] In one aspect of the present disclosure, a method, a computer-readable medium, and an apparatus are provided. The apparatus sends an indication of beam pattern information for a DL beam set to a UE, wherein the DL beam set is associated with a RIS. The apparatus receives a UL beam set from the UE based on an adjusted transmit angle derived from the beam pattern information for the DL beam set and a measurement, wherein the UL beam set is received from the UE via the RIS.

[0009] In one aspect of the present disclosure, a method, a computer-readable medium, and an apparatus are provided. The apparatus receives a plurality of SRS transmissions from a UE via at least one UE UL beam. The apparatus forwards the plurality of SRS transmissions to a network entity via a RIS UL beam set, wherein each RIS UL beam in the RIS UL beam set is associated with one UL control voltage in a UL control voltage set, and wherein each UL control voltage in the UL control voltage set is associated with a reflection angle of the at least one UE UL beam. The apparatus receives an indication from the network entity indicating a RIS UL beam from the RIS UL beam set, wherein the RIS UL beam is selected from the RIS UL beam set based on one or more measurements associated with the plurality of SRS transmissions. The apparatus forwards subsequent communications between the UE and the network entity based on a control voltage pair, the control voltage pair comprising a DL control voltage and a UL control voltage from the UL control voltage set corresponding to the RIS UL beam indicated by the network entity.

[0010] To achieve the aforementioned and related purposes, one or more aspects include the features fully described below and particularly pointed out in the claims. The following description and the accompanying drawings set forth in detail some exemplary features of one or more aspects. However, these features indicate only some of the various ways in which the principles of the various aspects can be employed. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] Figure 1 is a diagram illustrating an example of a wireless communication system and an access network.

[0012] Figure 2A is a diagram illustrating an example of a first frame according to various aspects of the present disclosure.

[0013] Figure 2B is a diagram illustrating an example of downlink (DL) channels within a subframe according to various aspects of the present disclosure.

[0014] Figure 2C is a diagram illustrating an example of a second frame according to various aspects of the present disclosure.

[0015] Figure 2D is a diagram illustrating an example of uplink (UL) channels within a subframe according to various aspects of the present disclosure.

[0016] Figure 3 is a diagram illustrating an example of a base station and a user equipment (UE) in an access network.

[0017] Figure 4 is a diagram illustrating an example of UE positioning based on reference signal measurement.

[0018] Figure 5 is a diagram illustrating example communications between wireless devices on line-of-sight (LOS) and non-line-of-sight (NLOS) channels in accordance with various aspects of the present disclosure.

[0019] Figure 6 is a diagram illustrating an example reconfigurable smart surface according to various aspects of the present disclosure.

[0020] Figure 7 is a diagram illustrating an example of a reconfigurable smart surface (RIS) angular reciprocity between two wireless transmissions in accordance with various aspects of the present disclosure.

[0021] Figure 8 is a diagram illustrating example communications between a base station and a UE via a RIS according to various aspects of the present disclosure.

[0022] Fig. 9is a communication flow illustrating an example in which a UE estimates and adjusts its UL beam to align with a DL beam of a RIS based on beam pattern information associated with the RIS in accordance with various aspects of the present disclosure.

[0023] Fig.10 is a communication flow illustrating an example in which a UE estimates and adjusts its UL beam to align with a DL beam of a RIS based on beam pattern information associated with the RIS in accordance with various aspects of the present disclosure.

[0024] Fig.11 is a communication flow illustrating an example of a RIS performing RIS beam adaptation for beam refinement according to various aspects of the present disclosure.

[0025] Fig.12 is a flow chart of a method of wireless communication.

[0026] Fig.13 is a flow chart of a method of wireless communication.

[0027] Fig.14 are diagrams illustrating examples of hardware implementations for example apparatuses and / or network entities.

[0028] Fig.15 is a flow chart of a method of wireless communication.

[0029] Fig.16 is a flow chart of a method of wireless communication.

[0030] Fig.17 are diagrams illustrating examples of hardware implementations for example apparatuses and / or network entities.

[0031] Fig.18 is a flow chart of a method of wireless communication.

[0032] Fig.19 are diagrams illustrating examples of hardware implementations for example apparatuses and / or network entities. DETAILED DESCRIPTION

[0033] Various aspects presented herein can improve the performance and accuracy of RIS-based UE positioning, such as when the RIS has a limited number of available control voltage sets. Various aspects presented herein can also improve beam correspondence between a base station and a UE when the base station and the UE are communicating with each other via the RIS.

[0034] The specific embodiments described below in conjunction with the accompanying drawings are descriptions of various configurations and do not represent the only configurations in which the concepts described herein can be practiced. In order to provide a thorough understanding of the various concepts, the specific embodiments include specific details. However, these concepts can be practiced without these specific details. In some cases, well-known structures and components are shown in block diagram form to avoid blurring such concepts.

[0035] Several aspects of telecommunication systems are presented with reference to various apparatuses and methods. These apparatuses and methods are described in the following detailed description and illustrated in the accompanying drawings by various blocks, components, circuits, processes, algorithms, etc. (collectively referred to as "elements"). These elements may be implemented using electronic hardware, computer software, or any combination thereof. Whether these elements are implemented as hardware or software depends on the specific application and the design constraints imposed on the overall system.

[0036] As an example, an element, or any part of an element, or any combination of elements can be implemented as a "processing system", which includes one or more processors. Examples of processors include microprocessors, microcontrollers, graphics processing units (GPUs), central processing units (CPUs), application processors, digital signal processors (DSPs), reduced instruction set computing (RISC) processors, systems on chip (SoCs), baseband processors, field programmable gate arrays (FPGAs), programmable logic devices (PLDs), state machines, gated logic components, discrete hardware circuits, and other suitable hardware configured to perform various functionalities described throughout the present disclosure. One or more processors in a processing system can execute software. Whether referred to as software, firmware, middleware, microcode, hardware description language, or other terms, software should be broadly interpreted as meaning instructions, instruction sets, codes, code segments, program codes, programs, subroutines, software components, applications, software applications, software packages, routines, subroutines, objects, executables, threads of execution, procedures, functions, or any combination thereof.

[0037] Thus, in one or more example aspects, specific implementations and / or use cases, the described functionality may be implemented in hardware, software, or any combination thereof. If implemented in software, the functionality may be stored or encoded as one or more instructions or codes on a computer-readable medium. Computer-readable media include computer storage media. Storage media may be any available media that can be accessed by a computer. As an example, such computer-readable media may include random access memory (RAM), read-only memory (ROM), electrically erasable programmable ROM (EEPROM), optical disk storage, magnetic disk storage, other magnetic storage devices, combinations of these types of computer-readable media, or any other medium that can be used to store computer-executable code in the form of instructions or data structures that can be accessed by a computer.

[0038] Although various aspects, specific implementations and / or use cases are described in this application by the illustration of some examples, additional or different aspects, specific implementations and use cases may be generated in many different arrangements and scenarios. The various aspects, specific implementations and / or use cases described herein can be implemented across many different platform types, devices, systems, shapes, sizes and packaging arrangements. For example, various aspects, specific implementations and / or use cases can be generated via integrated chip specific implementations and other devices based on non-module components (e.g., end-user devices, vehicles, communication equipment, computing equipment, industrial equipment, retail / purchase equipment, medical equipment, artificial intelligence (AI) enabled devices, etc.). Although some examples may or may not be specifically for use cases or applications, the described examples may have a wide range of applicability. Various aspects, specific implementations and / or use cases can be in the range from chip-level or modular components to non-modular, non-chip-level specific implementations, and further to the range of aggregated, distributed or original equipment manufacturer (OEM) devices or systems in conjunction with one or more technologies herein. In some actual settings, the equipment combined with the various aspects and features described may also include additional components and features for implementing and practicing the claimed and described aspects. For example, the transmission and reception of wireless signals necessarily include multiple components for analog and digital purposes (e.g., hardware components including antennas, RF chains, power amplifiers, modulators, buffers, processors, interleavers, adders / summers, etc.) The techniques described herein can be practiced in a wide variety of devices of various sizes, shapes, and configurations, chip-level components, systems, distributed arrangements, aggregated or disaggregated components, end-user devices, etc.

[0039] The deployment of a communication system (such as a 5G NR system) can be arranged with various components or constituent parts in a variety of ways. In a 5G NR system or network, a network node, a network entity, a mobility element of a network, a radio access network (RAN) node, a core network node, a network element or a network equipment (such as a base station (BS) or one or more units (or one or more components) that perform base station functionality) can be implemented in an aggregated or decomposed architecture. For example, a BS (such as a Node B (NB), an evolved NB (eNB), an NR BS, a 5G NB, an access point (AP), a transmit receive point (TRP) or a cell, etc.) can be implemented as an aggregated base station (also referred to as an independent BS or a monolithic BS) or a decomposed base station.

[0040] A converged base station may be configured to utilize a radio protocol stack that is physically or logically integrated within a single RAN node. A decomposed base station may be configured to utilize a protocol stack that is physically or logically distributed between two or more units, such as one or more central or centralized units (CUs), one or more distributed units (DUs), or one or more radio units (RUs). In some aspects, a CU may be implemented within a RAN node, and one or more DUs may be co-located with the CU, or alternatively, may be geographically or virtually distributed in one or more other RAN nodes. A DU may be implemented to communicate with one or more RUs. Each of a CU, a DU, and a RU may be implemented as a virtual unit, i.e., a virtual central unit (VCU), a virtual distributed unit (VDU), or a virtual radio unit.

[0041] Base station operation or network design may take into account the aggregated nature of base station functionality. For example, a disaggregated base station may be used in an integrated access and backhaul (IAB) network, an open radio access network (O-RAN (network configuration such as that initiated by the O-RAN Alliance)), or a virtualized radio access network (vRAN, also known as a cloud radio access network (C-RAN)). Decomposition may include distributing functionality across two or more units at various physical locations, as well as virtually distributing functionality of at least one unit, which may enable flexibility in network design. Individual units of a disaggregated base station or disaggregated RAN architecture may be configured for wired or wireless communication with at least one other unit.

[0042] Figure 1 1 is a diagram 100 illustrating an example of a wireless communication system and an access network. The illustrated wireless communication system includes a disaggregated base station architecture. The disaggregated base station architecture may include one or more CUs 110 that may communicate directly with a core network 120 via a backhaul link, or indirectly with the core network 120 through one or more disaggregated base station units, such as a near real-time (near RT) RAN intelligent controller (RIC) 125 via an E2 link, or a non-real-time (non-RT) RIC 115 associated with a service management and orchestration (SMO) framework 105, or both. The CU 110 may communicate with one or more DUs 130 via corresponding midhaul links, such as an F1 interface. The DU 130 may communicate with one or more RUs 140 via corresponding fronthaul links. The RU 140 may communicate with corresponding UEs 104 via one or more radio frequency (RF) access links. In some implementations, a UE 104 may be served simultaneously by multiple RUs 140.

[0043] Each of the units (i.e., CU 110, DU 130, RU 140, and near-RT RIC 125, non-RT RIC 115, and SMO framework 105) may include or be coupled to one or more interfaces configured to receive or send signals, data, or information (collectively, signals) via a wired or wireless transmission medium. Each of the units or an associated processor or controller that provides instructions to the communication interfaces of these units may be configured to communicate with one or more of the other units via a transmission medium. For example, these units may include a wired interface that is configured to receive signals or send signals to one or more of the other units via a wired transmission medium. Additionally, these units may include a wireless interface that may include a receiver, transmitter, or transceiver (such as an RF transceiver) configured to receive and / or send signals to one or more of the other units via a wireless transmission medium.

[0044] In some aspects, CU 110 may host one or more higher layer control functions. Such control functions may include radio resource control (RRC), packet data convergence protocol (PDCP), service data adaptation protocol (SDAP), etc. Each control function may be implemented using an interface that is configured to communicate signals with other control functions hosted by CU 110. CU 110 may be configured to handle user plane functionality (i.e., central unit-user plane (CU-UP)), control plane functionality (i.e., central unit-control plane (CU-CP)), or a combination thereof. In some specific implementations, CU 110 may be logically split into one or more CU-UP units and one or more CU-CP units. When implemented in an O-RA configuration, the CU-UP unit may communicate bidirectionally with the CU-CP unit via an interface (such as an E1 interface). As needed, CU 110 may be implemented to communicate with DU 130 for network control and signaling.

[0045] DU 130 may correspond to a logical unit that includes one or more base station functions for controlling the operation of one or more RUs 140. In some aspects, DU 130 may host one or more of a radio link control (RLC) layer, a medium access control (MAC) layer, and one or more high physical (PHY) layers (such as modules for forward error correction (FEC) encoding and decoding, scrambling, modulation and demodulation, etc.) at least in part according to a functional split such as those defined by 3GPP. In some aspects, DU 130 may also host one or more low PHY layers. Each layer (or module) may be implemented using an interface that is configured to communicate signals with other layers (and modules) hosted by DU 130 or with control functions hosted by CU 110.

[0046] The lower layer functionality may be implemented by one or more RUs 140. In some deployments, the RU 140 controlled by the DU 130 may correspond to a logical node that hosts RF processing functions or low PHY layer functions (such as performing fast Fourier transform (FFT), inverse FFT (iFFT), digital beamforming, physical random access channel (PRACH) extraction and filtering, etc.), or both, based at least in part on a functional split (such as a lower layer functional split). In such an architecture, the RU 140 may be implemented to handle over-the-air (OTA) communications with one or more UEs 104. In some implementations, real-time and non-real-time aspects of control and user plane communications with the RU 140 may be controlled by the corresponding DU 130. In some scenarios, this configuration may enable the DU 130 and the CU 110 to be implemented in a cloud-based RAN architecture (such as a vRAN architecture).

[0047] The SMO framework 105 may be configured to support RAN deployment and provisioning of non-virtualized network elements and virtualized network elements. For non-virtualized network elements, the SMO framework 105 may be configured to support the deployment of dedicated physical resources for RAN coverage requirements, which may be managed via an operation and maintenance interface (such as an O1 interface). For virtualized network elements, the SMO framework 105 may be configured to interact with a cloud computing platform (such as an open cloud (O-Cloud) 190) to perform network element lifecycle management (such as instantiating virtualized network elements) via a cloud computing platform interface (such as an O2 interface). Such virtualized network elements may include, but are not limited to, CU 110, DU 130, RU 140, and near-RT RIC 125. In some specific implementations, the SMO framework 105 may communicate with hardware aspects of the 4G RAN (such as an open eNB (O-eNB) 111) via the O1 interface. Additionally, in some specific implementations, the SMO framework 105 may communicate directly with one or more RUs 140 via the O1 interface. The SMO framework 105 may also include a non-RT RIC 115 configured to support the functionality of the SMO framework 105 .

[0048] The non-RT RIC 115 may be configured to include logic functions that enable non-real-time control and optimization of RAN elements and resources, artificial intelligence (AI) / machine learning (ML) (AI / ML) workflows including model training and updating, or policy-based guidance of applications / features in the near-RT RIC 125. The non-RT RIC 115 may be coupled to or in communication with the near-RT RIC 125 (such as via an A1 interface). The near-RT RIC 125 may be configured to include logic functions that enable near-real-time control and optimization of RAN elements and resources via data collection and actions through an interface (such as via an E2 interface) that connects one or more CUs 110, one or more DUs 130, or both, and the O-eNB with the near-RT RIC 125.

[0049] In some implementations, in order to generate an AI / ML model to be deployed in the near-RT RIC 125, the non-RT RIC 115 may receive parameters or external enrichment information from an external server. Such information may be utilized by the near-RT RIC 125 and may be received from a non-network data source or from a network function at the SMO framework 105 or the non-RT RIC 115. In some examples, the non-RT RIC 115 or the near-RT RIC 125 may be configured to tune RAN behavior or performance. For example, the non-RT RIC 115 may monitor long-term trends and patterns of performance and employ AI / ML models to perform corrective actions through the SMO framework 105 (such as via reconfiguration of O1) or via the creation of RAN management policies (such as A1 policies).

[0050] At least one of the CU 110, the DU 130, and the RU 140 may be referred to as a base station 102. Therefore, the base station 102 may include one or more of the CU 110, the DU 130, and the RU 140 (each component is indicated by a dotted line to indicate that each component may be included in the base station 102 or may not be included in the base station). The base station 102 provides an access point to the core network 120 for the UE 104. The base station 102 may include a macro cell (a high-power cellular base station) and / or a small cell (a low-power cellular base station). Small cells include femto cells, pico cells, and micro cells. A network including both small cells and macro cells may be referred to as a heterogeneous network. A heterogeneous network may also include a home evolved Node B (eNB) (HeNB), which may provide services to a restricted group referred to as a closed subscriber group (CSG). The communication link between RU 140 and UE 104 may include uplink (UL) (also known as reverse link) transmission from UE 104 to RU 140 and / or downlink (DL) (also known as forward link) transmission from RU 140 to UE 104. The communication link may use multiple-input multiple-output (MIMO) antenna technology, including spatial multiplexing, beamforming and / or transmit diversity. The communication link may be through one or more carriers. For each carrier allocated in a carrier aggregation of up to YxMHz (x component carriers) for transmission in each direction, the base station 102 / UE 104 may use a spectrum of up to YMHz (e.g., 5MHz, 10MHz, 15MHz, 20MHz, 100MHz, 400MHz, etc.) bandwidth. These carriers may or may not be adjacent to each other. The allocation of carriers may be asymmetric with respect to DL and UL (e.g., more or fewer carriers may be allocated to DL than to UL). Component carriers may include a primary component carrier and one or more secondary component carriers. The primary component carrier may be referred to as a primary cell (PCell) and the secondary component carrier may be referred to as a secondary cell (SCell).

[0051] Some UEs 104 may communicate with each other using a device-to-device (D2D) communication link 158. The D2D communication link 158 may use DL / UL wireless wide area network (WWAN) spectrum. The D2D communication link 158 may use one or more sidelink channels, such as a physical sidelink broadcast channel (PSBCH), a physical sidelink discovery channel (PSDCH), a physical sidelink shared channel (PSSCH), and a physical sidelink control channel (PSCCH). The D2D communication may be through a variety of wireless D2D communication systems, such as, for example, Bluetooth, Wi-Fi based on the Institute of Electrical and Electronics Engineers (IEEE) 802.11 standard, LTE, or NR.

[0052] The wireless communication system may also include a Wi-Fi AP 150 that communicates with a UE 104 (also referred to as a Wi-Fi station (STA)) via a communication link 154, for example, in a 5 GHz unlicensed spectrum, etc. When communicating in an unlicensed spectrum, the UE 104 / AP 150 may perform a clear channel assessment (CCA) to determine whether a channel is available prior to communication.

[0053] The electromagnetic spectrum is typically subdivided into various categories, bands, channels, etc. based on frequency / wavelength. In 5GNR, two initial operating bands have been identified as frequency range designations FR1 (410 MHz-7.125 GHz) and FR2 (24.25 GHz-52.6 GHz). Although a portion of FR1 is greater than 6 GHz, FR1 is often referred to (interchangeably) as the "below 6 GHz" band in various documents and articles. A similar naming problem sometimes occurs with respect to FR2, which is often (interchangeably) referred to as the "millimeter wave" band in documents and articles, although it is different from the extremely high frequency (EHF) band (30 GHz-300 GHz) identified as the "millimeter wave" band by the International Telecommunication Union (ITU).

[0054] Frequencies between FR1 and FR2 are generally referred to as mid-band frequencies. Recent 5G NR research has identified the operating bands for these mid-band frequencies as frequency range designation FR3 (7.125GHz-24.25GHz). The bands falling within FR3 can inherit FR1 characteristics and / or FR2 characteristics, and therefore the features of FR1 and / or FR2 can be effectively extended to mid-band frequencies. In addition, higher frequency bands are currently being explored to extend 5G NR operations to more than 52.6GHz. For example, three higher operating bands have been identified as frequency range designations FR2-2 (52.6GHz-71GHz), FR4 (71GHz-114.25GHz) and FR5 (114.25GHz-300GHz). Each of these higher frequency bands falls within the EHF band.

[0055] In view of the above, unless otherwise specified, if the term "6 GHz or less" is used herein, it may broadly refer to frequencies that may be less than 6 GHz, may be within FR1, or may include mid-band frequencies. In addition, unless otherwise specified, if the term "millimeter wave" is used herein, it may broadly refer to frequencies that may include mid-band frequencies, may be within FR2, FR4, FR2-2, and / or FR5, or may be within the EHF band.

[0056] The base station 102 and the UE 104 may each include multiple antennas (such as antenna elements, antenna panels, and / or antenna arrays) to facilitate beamforming. The base station 102 may send a beamformed signal 182 to the UE 104 in one or more transmit directions. The UE 104 may receive the beamformed signal from the base station 102 in one or more receive directions. The UE 104 may also send a beamformed signal 184 to the base station 102 in one or more transmit directions. The base station 102 may receive the beamformed signal from the UE 104 in one or more receive directions. The base station 102 / UE 104 may perform beam training to determine the optimal receive direction and transmit direction for each of the base station 102 / UE 104. The transmit direction and receive direction of the base station 102 may be the same or different. The transmit direction and receive direction of the UE 104 may be the same or different.

[0057] The base station 102 may include and / or be referred to as a gNB, a Node B, an eNB, an access point, a base transceiver station, a radio base station, a radio transceiver, a transceiver function, a basic service set (BSS), an extended service set (ESS), a transmit receive point (TRP), a network node, a network entity, a network equipment, or some other suitable term. The base station 102 may be implemented as an integrated access and backhaul (IAB) node, a relay node, a sidelink node, an aggregated (monolithic) base station with a baseband unit (BBU) (including a CU and a DU) and a RU, or as a decomposed base station including one or more of a CU, a DU, and / or a RU. A set of base stations that may include decomposed base stations and / or aggregated base stations may be referred to as a next generation (NG) RAN (NG-RAN).

[0058] The core network 120 may include an access and mobility management function (AMF) 161, a session management function (SMF) 162, a user plane function (UPF) 163, a unified data management (UDM) 164, one or more location servers 168, and other functional entities. AMF 161 is a control node that handles signaling between UE 104 and the core network 120. AMF 161 supports registration management, connection management, mobility management, and other functions. SMF 162 supports session management and other functions. UPF 163 supports packet routing, packet forwarding, and other functions. UDM 164 supports the generation of authentication and key agreement (AKA) credentials, user identity handling, access authorization, and subscription management. One or more location servers 168 are illustrated as including a gateway mobile location center (GMLC) 165 and a location management function (LMF) 166. However, in general, the one or more location servers 168 may include one or more location / positioning servers, which may include one or more of the GMLC 165, LMF 166, position determination entity (PDE), serving mobile location center (SMLC), mobile positioning center (MPC), etc. GMLC 165 and LMF 166 support UE location services. GMLC 165 provides an interface for clients / applications (e.g., emergency services) to access UE positioning information. LMF 166 receives measurement and assistance information from NG-RAN and UE 104 via AMF 161 to calculate the location of UE 104. NG-RAN may determine the location of UE 104 using one or more positioning methods. Positioning UE 104 may involve signal measurements, position estimation, and optional speed calculation based on these measurements. Signal measurements may be performed by UE 104 and / or serving base station 102. The measured signals may be based on a satellite positioning system (SPS) 170 (e.g., one or more of a global navigation satellite system (GNSS), a global positioning system (GPS), a non-terrestrial network (NTN), or other satellite positioning / positioning systems), LTE signals, wireless local area network (WLAN) signals, Bluetooth signals, a terrestrial beacon system (TBS), sensor-based information (e.g., an atmospheric pressure sensor, a motion sensor), an NR enhanced cell ID (NR E-CID) method, NR signals (e.g., multi-round trip time (multi-RTT), DL angle of departure (DL-AoD), DL time difference of arrival (DL-TDOA), UL time difference of arrival (UL-TDOA), and UL angle of arrival (UL-AoA) positioning), and / or one or more of other systems / signals / sensors.

[0059] Examples of UE 104 include cellular phones, smart phones, session initiation protocol (SIP) phones, laptops, personal digital assistants (PDAs), satellite radios, global positioning systems, multimedia devices, video devices, digital audio players (e.g., MP3 players), cameras, game consoles, tablet computers, smart devices, wearable devices, vehicles, electric meters, gas pumps, large or small kitchen appliances, healthcare equipment, implants, sensors / actuators, displays, or any other similarly functional devices. Some of the UEs 104 may be referred to as IoT devices (e.g., parking meters, gas pumps, toasters, vehicles, heart monitors, etc.). UE 104 may also be referred to as stations, mobile stations, subscriber stations, mobile units, subscriber units, wireless units, remote units, mobile devices, wireless devices, wireless communication devices, remote devices, mobile subscriber stations, access terminals, mobile terminals, wireless terminals, remote terminals, mobile phones, user agents, mobile clients, clients, or some other suitable terminology. In some scenarios, the term "UE" may also be applied to one or more supporting devices, such as in a device constellation arrangement. One or more of these devices may access the network collectively and / or individually.

[0060] Reference again Figure 1In some aspects, the UE 104 may be configured to obtain an indication of beam pattern information for a DL beam set for a network entity, wherein the DL beam set is associated with a RIS; adjust a first transmit angle of a UL beam set based on the beam pattern information and measurements for the DL beam set, wherein the first transmit angle of the UL beam set is adjusted to be approximately aligned with a second transmit angle of the DL beam set from the RIS; and send the UL beam set to the network entity via the RIS (e.g., via the RIS communication component 198) based on the adjusted first transmit angle. In some aspects, the base station 102 may be configured to send an indication of beam pattern information for a DL beam set to a UE, wherein the DL beam set is associated with a RIS; and receive the UL beam set from the UE based on the adjusted transmit angle derived from the beam pattern information and measurements for the DL beam set, wherein the UL beam set is received from the UE via the RIS (e.g., via the RIS communication component 199). In certain aspects, RIS 103 may be configured to receive multiple SRS transmissions from a UE via at least one UE UL beam; forward the multiple SRS transmissions to a network entity via a RIS UL beam set, wherein each RIS UL beam in the RIS UL beam set is associated with one UL control voltage in a UL control voltage set, and wherein each UL control voltage in the UL control voltage set is associated with a reflection angle of the at least one UE UL beam; receive an indication from the network entity indicating a RIS UL beam from the RIS UL beam set, wherein the RIS UL beam is selected from the RIS UL beam set based on one or more measurements associated with the multiple SRS transmissions; and forward subsequent communications between the UE and the network entity based on a control voltage pair, the control voltage pair comprising a DL control voltage and a UL control voltage from the UL control voltage set corresponding to the RIS UL beam indicated by the network entity (e.g., via RIS communication component 197).

[0061] Figure 2A FIG200 is a diagram illustrating an example of a first subframe within a 5G NR frame structure. Figure 2B FIG230 is a diagram illustrating an example of DL channels within a 5G NR subframe. Figure 2C FIG250 is a diagram illustrating an example of a second subframe within a 5G NR frame structure. Figure 2D FIG280 is a diagram illustrating an example of UL channels within a 5G NR subframe. The 5G NR frame structure may be frequency division duplex (FDD) (wherein for a particular set of subcarriers (carrier system bandwidth), subframes within that subcarrier set are dedicated to either DL or UL), or may be time division duplex (TDD) (wherein for a particular set of subcarriers (carrier system bandwidth), subframes within that subcarrier set are dedicated to both DL and UL). Figure 2A , Figure 2C In the example provided, the 5G NR frame structure is assumed to be TDD, where subframe 4 is configured with slot format 28 (most of which are DL), where D is DL, U is UL, and F is flexible between DL / UL, and subframe 3 is configured with slot format 1 (all of which are UL). Although subframes 3 and 4 are shown as having slot formats 1 and 28, respectively, any particular subframe can be configured with any of the various available slot formats 0 to 61. Slot formats 0 and 1 are full DL and full UL, respectively. Other slot formats 2 to 61 include a mix of DL, UL and flexible symbols. The UE is configured with the slot format through the received slot format indicator (SFI) (dynamically configured through DL control information (DCI) or semi-statically / statically configured through radio resource control (RRC) signaling). Note that the following description also applies to the 5GNR frame structure as TDD.

[0062] FIG. 2A to FIG. 2D The frame structure is illustrated, and various aspects of the present disclosure may be applicable to other wireless communication technologies that may have different frame structures and / or different channels. A frame (10ms) may be divided into 10 subframes of equal size (1ms). Each subframe may include one or more time slots. A subframe may also include a microslot, which may include 7, 4, or 2 symbols. Each time slot may include 14 or 12 symbols, depending on whether the cyclic prefix (CP) is normal or extended. For a normal CP, each time slot may include 14 symbols, and for an extended CP, each time slot may include 12 symbols. The symbol on the DL may be a CP orthogonal frequency division multiplexing (OFDM) (CP-OFDM) symbol. The symbol on the UL may be a CP-OFDM symbol (for high throughput scenarios) or a discrete Fourier transform (DFT) extended OFDM (DFT-s-OFDM) symbol (also known as a single carrier frequency division multiple access (SC-FDMA) symbol) (for power-limited scenarios; limited to single-stream transmission). The number of slots within a subframe is based on the CP and the parameter set. The parameter set defines the subcarrier spacing (SCS) and effectively defines the symbol length / duration, which is equal to 1 / SCS.

[0063]

[0064] For normal CP (14 symbols / slot), different parameter sets μ0 to 4 allow 1, 2, 4, 8, and 16 slots per subframe, respectively. For extended CP, parameter set 2 allows 4 slots per subframe. Thus, for normal CP and parameter set μ, there are 14 symbols / slot and 2 μ timeslots / subframe. The subcarrier spacing can be equal to 2 μ*15kHz, where μ is parameter set 0 to 4. Therefore, the subcarrier spacing for parameter set μ=0 is 15kHz, and the subcarrier spacing for parameter set μ=4 is 240kHz. The symbol length / duration is inversely related to the subcarrier spacing. FIG. 2A to FIG. 2D An example of a parameter set μ=2 with a normal CP of 14 symbols per slot and 4 slots per subframe is provided. The slot duration is 0.25 ms, the subcarrier spacing is 60 kHz, and the symbol duration is about 16.67 μs. Within a frame set, there may be one or more different bandwidth parts (BWPs) that are frequency-division multiplexed (see Figure 2B ). Each BWP may have a specific parameter set and CP (normal or extended).

[0065] A resource grid may be used to represent a frame structure. Each slot includes a resource block (RB) (also referred to as a physical RB (PRB)) extending over 12 consecutive subcarriers. The resource grid is divided into a number of resource elements (REs). The number of bits carried by each RE depends on the modulation scheme.

[0066] like Figure 2A As illustrated, some of the REs carry reference (pilot) signals (RS) for the UE. The RS may include a demodulation RS (DM-RS) (indicated as R for a particular configuration, but other DM-RS configurations are possible) and a channel state information reference signal (CSI-RS) for channel estimation at the UE. The RS may also include a beam measurement RS (BRS), a beam refinement RS (BRRS), and a phase tracking RS (PT-RS).

[0067] Figure 2BExamples of various DL channels within a subframe of a frame are illustrated. A physical downlink control channel (PDCCH) carries DCI within one or more control channel elements (CCEs) (e.g., 1, 2, 4, 8, or 16 CCEs), each CCE including six RE groups (REGs), each REG including 12 consecutive REs in an OFDM symbol of an RB. A PDCCH within a BWP may be referred to as a control resource set (CORESET). The UE is configured to monitor PDCCH candidates in a PDCCH search space (e.g., a common search space, a UE-specific search space) during a PDCCH monitoring opportunity on a CORESET, wherein the PDCCH candidates have different DCI formats and different aggregation levels. Additional BWPs may be located at higher and / or lower frequencies on the channel bandwidth. A primary synchronization signal (PSS) may be within symbol 2 of a particular subframe of a frame. The PSS is used by UE 104 to determine subframe / symbol timing and physical layer identification. A secondary synchronization signal (SSS) may be within symbol 4 of a particular subframe of a frame. The SSS is used by the UE to determine the physical layer cell identity group number and the radio frame timing. Based on the physical layer identity and the physical layer cell identity group number, the UE can determine the physical cell identifier (PCI). Based on the PCI, the UE can determine the location of the DM-RS. The physical broadcast channel (PBCH) carrying the master information block (MIB) can be logically grouped with the PSS and SSS to form a synchronization signal (SS) / PBCH block (also referred to as an SS block (SSB)). The MIB provides the number of RBs in the system bandwidth and the system frame number (SFN). The physical downlink shared channel (PDSCH) carries user data, broadcast system information not sent via the PBCH (such as a system information block (SIB)), and paging messages.

[0068] like Figure 2C As illustrated, some of the REs carry DM-RS (indicated as R for a particular configuration, but other DM-RS configurations are possible) for channel estimation at the base station. The UE may send a DM-RS for a physical uplink control channel (PUCCH) and a DM-RS for a physical uplink shared channel (PUSCH). The PUSCH DM-RS may be sent in the first or first two symbols of the PUSCH. Depending on whether a short PUCCH or a long PUCCH is sent and depending on the specific PUCCH format used, the PUCCH DM-RS may be sent in different configurations. The UE may send a sounding reference signal (SRS). The SRS may be sent in the last symbol of a subframe. The SRS may have a comb structure, and the UE may send the SRS on one of the teeth of the comb. The SRS may be used by the base station for channel quality estimation to achieve frequency-dependent scheduling of the UL.

[0069] Figure 2DExamples of various UL channels within a subframe of a frame are illustrated. The PUCCH may be located at a position as indicated in one configuration. The PUCCH carries uplink control information (UCI), such as scheduling requests, channel quality indicators (CQI), precoding matrix indicators (PMI), rank indicators (RI), and hybrid automatic repeat request (HARQ) acknowledgement (ACK) (HARQ-ACK) feedback (i.e., one or more HARQ ACK bits indicating one or more ACKs and / or negative ACKs (NACKs)). The PUSCH carries data and may be used to carry, among other things, a buffer status report (BSR), a power headroom report (PHR), and / or UCI.

[0070] Figure 3 370 is a block diagram of a base station 310 in an access network communicating with a UE 350. In the DL, Internet Protocol (IP) packets may be provided to a controller / processor 375. The controller / processor 375 implements layer 3 and layer 2 functionality. Layer 3 includes a radio resource control (RRC) layer, and layer 2 includes a service data adaptation protocol (SDAP) layer, a packet data convergence protocol (PDCP) layer, a radio link control (RLC) layer, and a medium access control (MAC) layer. The controller / processor 375 provides RRC layer functionality associated with broadcasting of system information (e.g., MIB, SIB), RRC connection control (e.g., RRC connection paging, RRC connection establishment, RRC connection modification, and RRC connection release), inter-radio access technology (RAT) mobility, and measurement configuration for UE measurement reporting; PDCP layer functionality associated with header compression / decompression, security (encryption, decryption, integrity protection, integrity verification), and handover support functions; RLC layer functionality associated with delivery of upper layer packet data units (PDUs), error correction through ARQ, concatenation, segmentation and reassembly of RLC service data units (SDUs), re-segmentation of RLC data PDUs, and reordering of RLC data PDUs; and MAC layer functionality associated with mapping between logical channels and transport channels, multiplexing of MAC SDUs onto transport blocks (TBs), demultiplexing of MAC SDUs from TBs, scheduling information reporting, error correction through HARQ, priority handling, and logical channel prioritization.

[0071] The transmit (TX) processor 316 and receive (RX) processor 370 implement layer 1 functionality associated with various signal processing functions. Layer 1 (which includes the physical (PHY) layer) may include error detection on the transport channel, forward error correction (FEC) coding / decoding of the transport channel, interleaving, rate matching, mapping to the physical channel, modulation / demodulation of the physical channel, and MIMO antenna processing. The TX processor 316 handles the mapping to the signal constellation based on various modulation schemes (e.g., binary phase shift keying (BPSK), quadrature phase shift keying (QPSK), M-order phase shift keying (M-PSK), M-order quadrature amplitude modulation (M-QAM)). The coded and modulated symbols can then be split into parallel streams. Each stream can then be mapped to an OFDM subcarrier, multiplexed with a reference signal (e.g., pilot) in the time and / or frequency domain, and then combined using an inverse fast Fourier transform (IFFT) to produce a physical channel carrying a time domain OFDM symbol stream. The OFDM stream is spatially pre-coded to generate multiple spatial streams. Channel estimates from a channel estimator 374 may be used to determine the coding and modulation schemes, as well as for spatial processing. Channel estimates may be derived from reference signals and / or channel condition feedback sent by the UE 350. Each spatial stream may then be provided to a different antenna 320 via a separate transmitter 318Tx. Each transmitter 318Tx may modulate a radio frequency (RF) carrier with a corresponding spatial stream for transmission.

[0072] At the UE 350, each receiver 354Rx receives a signal through its corresponding antenna 352. Each receiver 354Rx recovers the information modulated onto the RF carrier and provides the information to a receive (RX) processor 356. The TX processor 368 and the RX processor 356 implement layer 1 functionality associated with various signal processing functions. The RX processor 356 can perform spatial processing on the information to recover any spatial stream destined for the UE 350. If multiple spatial streams are destined for the UE 350, they can be combined into a single OFDM symbol stream by the RX processor 356. The RX processor 356 then uses a fast Fourier transform (FFT) to convert the OFDM symbol stream from the time domain to the frequency domain. The frequency domain signal includes a separate OFDM symbol stream for each subcarrier of the OFDM signal. The symbols on each subcarrier and the reference signal are recovered and demodulated by determining the signal constellation point most likely to be sent by the base station 310. These soft decisions can be based on channel estimates calculated by the channel estimator 358. The soft decisions are then decoded and deinterleaved to recover the data and control signals originally sent on the physical channel by the base station 310. The data and control signals are then provided to a controller / processor 359, which implements layer 3 and layer 2 functionality.

[0073] The controller / processor 359 may be associated with a memory 360 that stores program codes and data. The memory 360 may be referred to as a computer readable medium. In the UL, the controller / processor 359 provides demultiplexing between transport channels and logical channels, packet reassembly, decryption, header decompression, and control signal processing to recover IP packets. The controller / processor 359 is also responsible for error detection using ACK and / or NACK protocols to support HARQ operations.

[0074] Similar to the functionality described in conjunction with DL transmissions performed by the base station 310, the controller / processor 359 provides RRC layer functionality associated with system information (e.g., MIB, SIB) acquisition, RRC connection, and measurement reporting; PDCP layer functionality associated with header compression / decompression and security (encryption, decryption, integrity protection, integrity verification); RLC layer functionality associated with delivery of upper layer PDUs, error correction through 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 of MAC SDUs onto TBs, demultiplexing of MAC SDUs from TBs, scheduling information reporting, error correction through HARQ, priority handling, and logical channel prioritization.

[0075] Channel estimates derived by the channel estimator 358 based on a reference signal or feedback sent by the base station 310 may be used by the TX processor 368 to select appropriate coding and modulation schemes and to facilitate spatial processing. The spatial streams generated by the TX processor 368 may be provided to different antennas 352 via separate transmitters 354Tx. Each transmitter 354Tx may modulate an RF carrier with a corresponding spatial stream for transmission.

[0076] UL transmissions are processed at the base station 310 in a manner similar to that described in conjunction with the receiver functionality at the UE 350. Each receiver 318Rx receives a signal through its respective antenna 320. Each receiver 318Rx recovers information modulated onto an RF carrier and provides the information to the RX processor 370.

[0077] The controller / processor 375 may be associated with a memory 376 that stores program codes and data. The memory 376 may be referred to as a computer readable medium. In the UL, the controller / processor 375 provides demultiplexing between transport channels and logical channels, packet reassembly, decryption, header decompression, control signal processing to recover IP packets. The controller / processor 375 is also responsible for error detection using ACK and / or NACK protocols to support HARQ operations.

[0078] At least one of the TX processor 368, the RX processor 356, and the controller / processor 359 may be configured to perform operations related to Figure 1 Various aspects related to the RIS communication component 198.

[0079] At least one of the TX processor 316, the RX processor 370, and the controller / processor 375 may be configured to perform operations related to Figure 1 The triggering of the RIS communication component 199 is related to various aspects.

[0080] Figure 4 4 is a diagram illustrating an example of UE positioning based on reference signal measurements (which may also be referred to as “network-based positioning”) according to various aspects of the present disclosure. UE 404 may be at time T SRS_TX UL-SRS 412 is sent and at time T PRS_RX A DL positioning reference signal (PRS) (DL-PRS) 410 is received. TRP 406 may be at time T SRS_RX Receive UL-SRS 412 and at time T PRS_TX 410. UE 404 may receive DL-PRS 410 before transmitting UL-SRS 412, or may transmit UL-SRS 412 before receiving DL-PRS 410. In both cases, a positioning server (e.g., location server 168) or UE 404 may determine the UL-SRS 412 based on ||T SRS_RX -T PRS_TX |-|T SRS_TX -T PRS_RX || determines RTT 414. Thus, multi-RTT positioning may utilize UE Rx-Tx time difference measurements (i.e., |T SRS_TX -T PRS_RX |) and DL-PRS reference signal received power (RSRP) (DL-PRS-RSRP), and the measured TRP Rx-Tx time difference measurement (ie, |T SRS_RX -T PRS_TX|) and UL-SRS-RSRP. UE 404 measures UE Rx-Tx time difference measurement (and / or DL-PRS-RSRP of received signals) using assistance data received from the positioning server, and TRP 402, 406 measures gNB Rx-Tx time difference measurement (and / or UL-SRS-RSRP of received signals) using assistance data received from the positioning server. These measurements may be used at the positioning server or UE 404 to determine RTT, which is used to estimate the position of UE 404. Other methods for determining RTT are possible, such as, for example, using DL-TDOA and / or UL-TDOA measurements.

[0081] DL-AoD positioning may utilize the measured DL-PRS-RSRP of downlink signals received from multiple TRPs 402, 406 at the UE 404. The UE 404 measures the DL-PRS-RSRP of the received signals using assistance data received from a positioning server, and the resulting measurements, along with the departure azimuth angle (A-AoD), departure zenith angle (Z-AoD), and other configuration information, are used to position the UE 404 relative to neighboring TRPs 402, 406.

[0082] DL-TDOA positioning may utilize DL reference signal time difference (RSTD) (and / or DL-PRS-RSRP) of downlink signals received from multiple TRPs 402, 406 at the UE 404. The UE 404 measures the DL RSTD (and / or DL-PRS-RSRP) of the received signals using assistance data received from a positioning server, and the resulting measurements are used along with other configuration information to position the UE 404 relative to neighboring TRPs 402, 406.

[0083] UL-TDOA positioning may utilize the UL relative time of arrival (RTOA) (and / or UL-SRS-RSRP) of uplink signals sent from UE 404 at multiple TRPs 402, 406. TRPs 402, 406 measure the UL-RTOA (and / or UL-SRS-RSRP) of received signals using assistance data received from a positioning server, and the resulting measurements are used along with other configuration information to estimate the position of UE 404.

[0084] UL-AoA positioning may utilize the measured azimuth angle of arrival (A-AoA) and zenith angle of arrival (Z-AoA) of uplink signals sent from the UE 404 at multiple TRPs 402, 406. The TRPs 402, 406 measure the A-AoA and Z-AoA of the received signals using assistance data received from a positioning server, and the resulting measurements are used along with other configuration information to estimate the position of the UE 404.

[0085] Additional positioning methods may be used to estimate the position of the UE 404, such as, for example, UE-side UL-AoD and / or DL-AoA. Note that data / measurements from various techniques may be combined in various ways to increase accuracy, determine and / or enhance certainty, supplement / complement measurements, and / or replace / provide missing information. For the purposes of this disclosure, the suffixes "based on" and "assisted" may refer to a node responsible for performing positioning calculations (and may also provide measurements) and a node providing measurements (but may not perform positioning calculations), respectively. For example, operations in which a UE provides measurements to a base station / positioning entity for use in calculating a position estimate may be described as "UE-assisted", "UE-assisted positioning", and / or "UE-assisted position calculation", while operations in which a UE calculates its own position may be described as "UE-based", "UE-based positioning", and / or "UE-based position calculation". In addition, when UE positioning involves a reconfigurable smart surface (RIS), UE positioning may also be referred to as RIS-based UE positioning. For example, during RIS-based UE positioning, a UE may send an SRS to a base station via a RIS and / or receive a PRS from a base station via a RIS, etc.

[0086] In some scenarios, for UL-based positioning, the UE may be configured to perform UL beam management on the SRS, such as by performing beam selection on the SRS based on measurements of other reference signals. For example, there may be a spatial relationship between the SRS and a DL-PRS, SSB, or another SRS used for positioning, where the UE may perform measurements on these reference signals and select one or more beams for sending the SRS based on the measurements. In some examples, the spatial relationship may be configured for the UE (e.g., by a serving base station, a location server, or an LMF, etc.). For example, a base station or an LMF may configure the UE with a spatial relationship between a reference DLRS from a serving cell and a target SRS for positioning of the UE, where the reference DL RS may include an SSB, a CSI-RS (e.g., NZP-CSI-RS-ResourceId), or a PRS used for positioning, etc. In another example, the base station or the LMF configures the UE with a spatial relationship between two SRSs for positioning. If the spatial relationship is associated with the SSB (for example, the SSB is used as a DL RS for UL beam management), the SSB may be configured to include one or more of the following items: the PCI of the cell; ssbFrequency, value: ARFCN-ValueNR; halfFrameIndex, value: 0 or 1; SSB-periodicity, value: ServingCellConfigCommon IE; ssbSubcarrierSpacing, value: SubcarrierSpacing IE; SFN-SSBoffset, value: {0,1,2,…15}; Smtc for each SSB frequency layer, value: SSB-MTC; SFN0 Offset for each physical cell ID: the time offset of SFN0 time slot 0 of a given cell relative to the serving PCell; SSB index; SS-PBCH-BlockPower (at least when the SSB is used as the pathlossReferenceRS of the SRS), etc.

[0087] The accuracy of UE positioning may be affected by whether the positioning entities (eg, UE, base station, sidelink device, etc.) are in line-of-sight (LOS) or non-line-of-sight (NLOS) conditions with respect to each other. Figure 55 is a diagram illustrating an example communication between wireless devices regarding LOS and NLOS channels according to various aspects of the present disclosure. A transmitting entity 502 (e.g., a first UE or a first base station, etc.) may be configured or scheduled to transmit a data signal or a reference signal (RS) (e.g., a positioning reference signal) to a receiving entity 504 (e.g., a second UE or a second base station, etc.). In some scenarios, as shown at 508, the data / RS transmitted from the transmitting entity 502 may directly reach the receiving entity 504 without being blocked by obstacles. In other scenarios, as shown at 510, the data / RS transmitted from the transmitting entity 502 may indirectly reach the receiving entity 504 via reflection, refraction, and / or penetration, etc. (e.g., one or more objects 512 may block the transmission path of the data or may be within the transmission path of the data). The time for signals traveling via NLOS paths / channels may also be longer because signals traveling via NLOS paths / channels, such as shown at 510, may arrive at the receiving entity 504 later and / or with less power than signals traveling via LOS paths / channels (e.g., paths / channels without obstacles), such as shown at 508. Therefore, if the calculation or estimate of the distance between the sending entity 502 and the receiving entity 504 is based on NLOS measurements, the calculation or estimate of the distance may be inaccurate.

[0088] For purposes of this disclosure, signal / data transmission that is not obstructed by an obstacle may be referred to as "LOS transmission," "LOS signal / data," "signal / data transmitted via a LOS path / channel," etc., and signal / data transmission that is obstructed by an obstacle may be referred to as "NLOS transmission," "NLOS signal / data," "signal / data transmitted via a NLOS path / channel," etc. (e.g., signal / data transmission with respect to reflection, refraction, and / or penetration, etc.). Signal reflection may refer to a signal sent from a transmitter in a signal / beam path that bounces off one or more objects before reaching a receiver. Signal refraction may refer to a signal sent from a transmitter in a signal / beam path and that changes its direction when it passes through an obstacle (e.g., a material or medium that the signal is able to pass / penetrate) before reaching a receiver. Signal penetration may refer to a signal sent from a transmitter in a signal / beam path and that penetrates an object or medium before reaching a receiver.

[0089] To improve communication between wireless devices in NLOS conditions (or not in LOS conditions), the wireless devices may use a reconfigurable smart surface (RIS) (which may also be referred to as a "reflective smart surface") to assist in their signal transmission / reception (or relaying). Figure 6600 is a diagram illustrating an example reconfigurable smart surface according to various aspects of the present disclosure. As shown at 602, a RIS may be a planar structure engineered / configured to have properties that enable dynamic control of electromagnetic waves. For example, a RIS may be a node that can receive a signal from a first wireless device (e.g., a transmitter) and then reradiate or reflect the signal to a second wireless device (e.g., a receiver) with a controllable time delay. In another example, a RIS may be an artificial structure with engineered electromagnetic (EM) properties that can collect wireless signals from a transmitter and passively beamform them to a desired receiver.

[0090] The RIS may include a phased array without a transceiver, and the RIS may be designed based on antennas or metamaterials, where the RIS may be configured to reflect or reradiate signals to one or more directions. For example, phase shift control may be integrated with an antenna panel to control the phase shift of the antenna panel. The RIS may include multiple small elements associated with different time delays, so that the RIS may be able to synthesize the scattering behavior of arbitrarily shaped objects of the same size. For example, this feature may be used to beamform signals toward a receiving wireless device.

[0091] In some examples, as shown at 604, the RIS may also be associated with a RIS controller, where the RIS controller may control one or more antenna arrays to receive signals / reflect signals toward one or more directions. In one example, control of the RIS may be based on a defined set of control voltages, where each control voltage may correspond to a particular reflection angle (which may be referred to as a "control voltage set"). For example, a first control voltage set may include a first control voltage (e.g., 0.25V) corresponding to a first reflection angle (e.g., 30°) or a first reflection coefficient, and a second control voltage set may include a second control voltage (e.g., 0.5V) corresponding to a second reflection angle (e.g., 45°) or a second reflection coefficient, etc. The number of control voltage sets available for each RIS may be limited. For example, the RIS may be limited to a maximum of ten or fifteen control voltage sets (e.g., for the purpose of reducing manufacturing costs).

[0092] The RIS controller may be able to communicate with other wireless nodes (e.g., UE, base station, RSU, etc.). Thus, the RIS may be used to extend the coverage of a cellular system with negligible power consumption. In addition, the RIS may be a nearly passive device that reflects an incident wave to a desired direction, wherein the reflection direction is controlled by a base station. For example, in a cellular network, a network node (e.g., a base station) may control the RIS, wherein the network node may determine / configure one or more parameters of the RIS, such as activation / deactivation time, phase, beam direction, and / or beamforming weights used by the RIS, etc. The base station may indicate the determined / configured parameters to one or more UEs, and the UE may use the RIS to assist in the transmission and / or reception of signals with other UEs based at least in part on the determined / configured parameters. The communication link between the base station and the RIS may be wired or wireless. In some examples, the RIS may be used as a UE (e.g., the RIS includes hardware components and / or functions of the UE). In other examples, the RIS may be co-located or associated with the UE so that the RIS may communicate with the base station or another UE via the UE.

[0093] Since the RIS may be able to reflect or reradiate signals to different directions, wireless devices may use the RIS to transform the NLOS path / channel to a path / channel close to or similar to the LOS path / channel by reflecting / relaying signals sent between wireless devices. Figure 6 As shown at 606 of , when the first wireless device and the second wireless device are in a NLOS condition (e.g., the wireless devices are not in a LOS condition between the first wireless device and the third wireless device), the first wireless device may use RIS to improve its communication with the second wireless device, wherein the first wireless device may send a signal to the second wireless device via RIS, and vice versa. The wireless devices may also use RIS to improve network coverage / throughput and reduce power consumption. For example, RIS may be configured to reflect a signal sent from a sending device toward a direction or area not covered by the signal (e.g., a coverage blind spot, etc.) with less power than increasing the transmission power of the sending device.

[0094] Figure 7 700 is a diagram illustrating an example of RIS angle reciprocity between two signal transmissions in accordance with various aspects of the present disclosure. In some scenarios, when two wireless nodes (e.g., UEs, base stations, RSUs, sidelink devices, or combinations thereof) are communicating with each other via RIS, RIS angle reciprocity may not hold between the signal transmissions of the two wireless nodes. For example, as shown at 702, a first wireless node may transmit a signal from an incident angle of 0 degrees relative to RIS (e.g., θ inc =0°) to the RIS, and the RIS may transmit a first signal (which may be referred to as an incident signal) to the RIS via a reflection angle (eg, θref =30°) reflects the first signal (which may be referred to as the reflected signal) to the second wireless node, where the RIS may be operating at a first control voltage (eg, ) operation, the first control voltage corresponding to the first reflection angle / coefficient (e.g., a first control voltage set).

[0095] As shown at 704, in response to receiving the first signal, the second wireless node may send a second signal to the RIS via the direction in which the second wireless node received the first signal, for example, the second wireless node transmits a second signal at an incident angle of 30 degrees relative to the RIS (e.g., θ inc =30°). However, the second signal may not be reflected from the RIS at the same reflection angle as the first signal's angle of incidence relative to the RIS. In other words, if the RIS is transmitting a second signal at a first control voltage corresponding to a first reflection angle / coefficient (e.g., ) operation, the second signal can be reflected to a different angle (e.g., θ ref ≠0°). Therefore, the first wireless node may not receive the second signal, or may receive a degraded second signal.

[0096] As shown at 706, for the RIS, in order to reflect the image at a reflection angle of 0 degrees relative to the RIS (e.g., θ ref =0°) to reflect a second signal (e.g., to maintain angular reciprocity), RIS may be specified to reflect a second signal at a second control voltage (e.g., ) operation, the second control voltage corresponds to a second, different reflection coefficient (e.g., a second set of control voltages). Therefore, in order for the first wireless node and the second wireless node to maintain beam correspondence for their communication, a pair of control voltage sets (e.g., for θ inc →θ ref The first control voltage set and for θ ref →θ inc The second control voltage set ). Beam correspondence may refer to two wireless nodes communicating with each other using the same beam set or beam direction for transmission and reception. For example, beam correspondence between a base station and a UE may refer to a beam selected for downlink transmission and reception that can also be used for uplink transmission and reception.

[0097] Figure 8800 is a diagram illustrating example communications between a base station 802 (e.g., a first wireless node) and a UE 804 (e.g., a second wireless node) via a RIS 806 in accordance with various aspects of the present disclosure. For purposes of the present disclosure, a beam used by the base station 802 to transmit signals to the UE 804 (or to the UE 804 via the RIS 806) as shown at 808 may be referred to as a base station DL beam. A beam used by the UE 804 to transmit signals to the base station 802 (or to the base station 802 via the RIS 806) as shown at 810 may be referred to as a UE UL beam. As shown at 812, the beam used by RIS 806 to send signals to base station 802 (e.g., for reflecting signals from UE 804 to base station 802) may be referred to as a RIS UL beam or a RIS UL transmit beam, and as shown at 814, the beam used by RIS 806 to send signals to UE 804 (e.g., for reflecting signals from base station 802 to UE 804) may be referred to as a RIS DL beam or a RIS DL transmit beam.

[0098] In some scenarios, beams or beam pairs between base station 802 and RIS 806 (e.g., between base station DL beams and RIS UL beams) may be maintained or fixed to provide the best link quality between base station 802 and RIS 806 because they are more likely to be in a fixed position. For example, a RIS UL receive beam set (e.g., a RIS beam used to receive signals from a UE UL beam) of RIS 806 may be configured to be fixed and mapped to one or more pairs of control voltage sets. For example, a RIS UL receive beam may be pointing in a first direction relative to the RIS and may correspond to a first pair of control voltage sets, for example, one control voltage set for reflecting signals received from base station 802 to a specific angle (e.g., 45°) and one control voltage for reflecting signals received at a specific angle (e.g., 45°) back to base station 802, etc.

[0099] In one example, as shown at 816, when there is a mismatch between a RIS DL / UL beam (e.g., a fixed beam) and a UE UL beam (e.g., not fixed in most cases), the quality (e.g., SNR) of UL communication may be significantly degraded, especially when UE 804 is in a blocked area (e.g., base station 802 and UE 804 are not in a LOS condition). A mismatch of beams may refer to a UE UL beam not being aligned with a corresponding RIS DL beam. For example, a mismatch of beams may occur when RIS 806 transmits / reflects a signal to UE 804 via a RIS DL beam at an angle of 30° relative to RIS 806, and in response, UE 804 transmits a signal to RIS 806 via a UE UL beam at an angle of 0° relative to RIS 806. Therefore, although the RIS UL beam control voltage may be fixed, due to the mobility of UE 804, in many instances, the UE UL beam may not perfectly match the RIS UL receive beam. In some scenarios, such a mismatch between the RIS UL receive beam and the UE UL beam may cause the UE UL beam to be reflected to a blocked area or not directed to an area of ​​the base station 802, such as shown at 816. Figure 6 As discussed, in some scenarios, there may be a limited number of control voltage sets available for RIS. For example, in a typical implementation, there may only be a limited pair of control voltage sets configured for a limited number of beam correspondences (e.g., in DL and UL). Therefore, when a mismatch between a RIS DL / UL beam and a UE UL beam occurs, it may be difficult for the base station 802 and the UE 804 to maintain beam correspondence.

[0100] Various aspects presented herein can improve the performance and accuracy of RIS-based UE positioning, such as when the RIS has a limited number of available control voltage sets. Various aspects presented herein can also improve beam correspondence between a base station and a UE when the base station and the UE are communicating with each other via the RIS.

[0101] In one aspect of the present disclosure, a UE may utilize the high accuracy of the UE DL-AoD estimate / calculation, and the UE may adjust the direction of its UL beam (e.g., UE UL beam) to align with the RIS DL beam based on the DL-AoD estimate / calculation, thereby achieving beam correspondence with the base station. Such a configuration may enable the RIS to use only a pair of control voltage sets. Since the DL-AoD for the RIS DL beam does not rely on the UE UL reception (e.g., the reception of the UE UL beam at the RIS), it may avoid the loss of UE UL beam quality due to beam mismatch. It should be noted that methods based on UL-AoA (e.g., the angle of arrival of the UE UL beam at the RIS) may not be well suited for calculating the DL-AoD of the RIS DL beam because it may rely on the UE UL reception (which may become inaccurate in the event of beam mismatch). For example, a network node (e.g., a base station, a location server, an LMF, etc.) may signal beam pattern information associated with a RISDL beam of a RIS to a UE, where the UE may be performing UE positioning with the base station or communicating with the base station via the RIS. The beam pattern information may include beam patterns and / or information related to the RISDL beam of the RIS, such as the angle, intensity, number of arrays, beam width (e.g., 3dB beam width), and / or line-of-sight direction of the RISDL beam, etc. In some examples, the beam pattern information may also include beam patterns / information for various DL beams / signals, such as beam patterns / information for PRS, SSB, and / or CSI-RS, etc. (e.g., which beams are sending which DL signals, the periodicity of the DL signals, the resources used by the DL signals, etc.). For example, if the beam patterns of one or more DL signals are quasi-co-located (QCL) with the SRS sent from the UE, these beam patterns may be signaled to the UE. The UE may then determine / calculate the AoD of one or more RISDL beams based on the beam pattern information (eg, such as for UE-based AoD positioning).

[0102] In one example, the UE may calculate / estimate the direction for sending one or more UL beams based on RSRP measurement (which may be referred to as RSRP-based direction estimation). For example, the UE may measure the RSRP of a PRS / RISDL beam set (or all PRS / RISDL beams). Based on the knowledge of the beam patterns of all PRS / RISDL beams, the UE may match the relative RSRP between different beams with a database formulated based on the PRS / RISDL beam patterns. Therefore, there is a mapping between the direction for sending one or more UL beams and the database formulated by all PRS / RISDL beam patterns. Such RSRP-based direction estimation methods may specify that the base station includes additional information in the beam pattern information in addition to the line of sight information of the RISDL beam, such as information associated with the DL signal sent from the RISDL beam. Therefore, additional signaling may be specified / configured between the base station and the UE. For the purposes of this disclosure, line of sight information may refer to information that enables a transmitting device / node such as a UE or a base station to adjust its transmit (Tx) beam (or send a signal) to a specified direction. For example, the line of sight information may include the azimuth and elevation of the RISDL beam. In addition, when two beams are aligned, this may indicate that the two beams have close (e.g., within a threshold) or identical Tx / Rx angles relative to each other or relative to a reference point. For example, when the RIS transmits / reflects a signal to the UE via the RIS DL beam at an angle of 30° relative to the RIS, and in response, the UE also transmits a signal to the RIS via the UE UL beam at an angle of 30° (or 30°+ / -X° for more flexible deployment), the UE UL beam may be considered to be aligned with the RIS DL beam. In other examples, the two beams may be aligned when they are parallel to or pointing toward each other. For example, if a Tx beam of a first wireless device and an Rx beam of a second wireless device are pointing toward each other to establish a communication link, the two beams may be aligned.

[0103] In another example, the UE may use a method based on Rx digital beamforming to calculate / estimate the direction for sending one or more UE UL beams. For example, the UE may capture a set of samples sent from another wireless device / node, and then the UE may apply different Rx beams (referred to as digital Rx beamforming) to the sample sets to find the Rx beam that is closest to the direction from the RIS to the UE. Such a direction calculation / estimation method may specify only the line of sight information of the RIS DL beam, which may use less signaling overhead between the UE and the base station (but may also specify higher UE capabilities) compared to RSRP-based direction estimation.

[0104] In one aspect, the UE may indicate which direction calculation / estimation method the UE uses or recommends, and the UE may receive corresponding beam pattern information based on the indication. For example, the UE may indicate a method for calculating / estimating the direction for sending its UL beam to a network (e.g., a base station, a location server, or an LMF, etc.) via a UE capability report or via dedicated signaling (e.g., RRC signaling), and the UE may then receive corresponding beam pattern information from the network (e.g., via assistance data), which beam pattern information may be used to calculate / estimate the direction for sending its UL beam. In some scenarios, the UE may also be specified to support a specific method / mechanism for calculating / estimating the direction for sending its UL beam. For example, the UE may be specified to support the capability of an Rx digital beamforming-based method for calculating the direction for sending its UL beam (e.g., antenna array capabilities for Rx beamforming and array orientation calibration). If the UE does not support such a direction calculation / estimation method, the UE may be prevented from estimating the direction for sending its UL beam.

[0105] In another example, unless the UE indicates otherwise, it may be assumed by default that the UE is using one of the direction estimation / calculation methods. For example, it may be assumed by default that the UE uses RSRP-based direction estimation because such methods / mechanisms may have lower specifications on the UE side than Rx digital beamforming-based methods (e.g., RSRP-based direction estimation is more likely to be performed by UEs that do not have high capabilities). However, if the UE indicates that it has the capability to support the digital Rx beamforming-based method, the assistance data signaling may be greatly reduced because only the beam boresight information may be specified for the UE.

[0106] Based on the direction estimated / calculated by the UE for transmitting its UL beam, the UE may adjust its UE UL beam or beam transmission to align with the boresight direction of one or more RISDL beams (e.g., RISDL beams used to reflect signals from base stations). In some examples, the UE may specify real-time antenna panel / UE orientation calibration to maintain beam alignment between the UE and the RIS.

[0107] By enabling the UE to estimate the direction for transmitting its UL beam based on beam pattern information and measurements associated with the RIS for the RIS DL beam, the UE may be able to maintain beam correspondence with the base station via the RIS without specifying a large number of control voltage sets at the RIS. For example, only one pair of control voltage sets may be specified at the RIS, which may include a first control voltage set for reflecting a signal received from the base station to the UE via the RIS DL beam and a second control voltage set for reflecting a signal received from the UE back to the base station, such as in Figure 7 As shown at 706. Therefore, the positioning of the UE and / or the RIS-based communication between the base station and the UE can be improved.

[0108] In another aspect of the present disclosure, the network may not be specified to signal beam pattern information associated with the RIS DL beam to the UE. Instead, the UE may report RSRP measurements for one or more RIS DL beams to the network. The network may then derive the angular difference between the RIS DL beam and the UE's AoD based on the RSRP measurements, and the network may signal the derived angular difference to the UE. The UE may then adjust its UE UL beam or beam transmission to align with the RIS DL beam based on the angular difference. This configuration may be appropriate when the base station cannot provide beam pattern information for the RIS (e.g., the beam pattern information associated with the RIS is proprietary).

[0109] Fig. 9 900 is a communication flow illustrating an example in which a UE estimates and adjusts its UL beam to align with a DL beam of a RIS based on beam pattern information associated with the RIS according to various aspects of the present disclosure. The numbers associated with the communication flow 900 do not specify a particular time sequence and are merely used as a reference for the communication flow 900. Various aspects presented herein may enable a UE to maintain beam correspondence with a base station via a RIS having a limited number of control voltage sets (e.g., having a pair of control voltage sets).

[0110] At 920, base station 902 may be communicating with UE 904 via RIS 906, such as in conjunction with Figure 8 As described, the base station 902 may send beam pattern information 908 associated with the RISDL beam set 910 of the RIS 906 to the UE 904 (eg, directly or via the RIS 906).

[0111] At 922, based on the beam pattern information 908 and the measurement for the RISDL beam set 910 (e.g., the UE 904 may perform the measurement on the RISDL beam set 910 before 922), the UE 904 may calculate the direction 912 for transmitting the UL beam (i.e., the UE UL beam) set 914. In one example, in order for the UE 904 to calculate the direction 912, the beam pattern information 908 may include the beam pattern of one or more DL signals, such as the beam pattern of the PRS, SSB, and / or CSI-RS. As described above, the UE 904 may measure the RISDL beam set 910 using the Rx digital beamforming-based method and / or the RSRP-based direction estimation method to calculate the direction 912 for transmitting the UL beam set 914.

[0112] In one example, as shown at 928, the UE 904 may indicate the method it will use to calculate the direction 912 or the method it recommends to use to calculate the direction 912. In one example, the indication may be based on the capabilities of the UE 904 (e.g., whether the UE 904 supports the specified method for calculating the direction 912). Based on the indication, the base station 902 may include corresponding information in the beam pattern information 908 that may be used by the UE 904 to calculate the direction 912 using the method specified by the UE 904. For example, if the UE 904 specifies that it is using an RSRP-based direction estimate to calculate the direction 912, the base station 902 may include a beam pattern of one or more DL reference signals in the beam pattern information 908.

[0113] At 924, after calculating the direction 912 for transmitting the UL beam set 914, the UE 904 may adjust the Tx angle of the UL beam set 914 (e.g., the beam used for communicating with the base station 902) based on the calculated direction 912 (e.g., based on the beam pattern information 908 and the measurement for the RISDL beam set 910). For example, the UE 904 may adjust the Tx angle of the UL beam set 914 based on the calculated direction 912 for transmitting the UL beam set 914 to align or approximately align with the transmit angle of the RISDL beam set 910 (e.g., within a certain range, such as X°+ / −Y°).

[0114] At 926, the UE 904 may signal / transmit from the UL beam set 914 to the base station 902 via the RIS 906 based on the adjusted Tx angle. Thus, the UE 904 may be able to maintain beam correspondence with the base station 902 via the RIS 906 using a pair of control voltage sets at the RIS 906.

[0115] Fig.10 1000 is an example communication flow illustrating that a UE estimates and adjusts its UL beam to align with a DL beam of a RIS based on beam pattern information associated with the RIS according to various aspects of the present disclosure. The numbers associated with the communication flow 1000 do not specify a particular time sequence and are merely used as a reference for the communication flow 1000. Various aspects presented herein may enable a UE to maintain beam correspondence with a base station via a RIS having a limited number of control voltage sets (e.g., having a pair of control voltage sets).

[0116] At 1020 , the UE 1004 may measure the RSRP of the RISDL beam set 1010 from the RIS 1006 , where the UE 1004 may be communicating with the base station 1002 via the RIS 1006 .

[0117] At 1022, UE 1004 may report RSRP measurements for RISDL beam set 1010 to the base station.

[0118] At 1024 , after receiving the RSRP measurement for the RISDL beam set 1010 , the base station 1002 may calculate and derive the angular difference 1012 between the RISDL beam 1010 and the AoD of the UE 1004 based on the RSRP measurement.

[0119] At 1026 , the base station 1002 may indicate the derived angle difference 1012 to the UE 1004 .

[0120] At 1028, after receiving the angle difference 1012 indication, the UE 1004 may adjust the Tx angle of the UE UL beam set 1014 based on the angle difference 1012. For example, the UE 1004 may adjust the Tx angle of the UE UL beam set 1014 based on the angle difference 1012 to approximately align with the transmit angle of the DL beam set 1010.

[0121] At 1030, UE 1004 may signal / transmit from UE UL beam set 1014 to base station 1002 via RIS 1006 based on the adjusted Tx angle. Thus, UE 1004 may be able to maintain beam correspondence with base station 1002 via RIS 1006 using a pair of control voltage sets at RIS 1006.

[0122] Combination Fig. 9 and Fig.10 The described aspects may not specify the RIS to perform any adaptation, but may specify UL beam adaptation at the UE. In other words, most configurations may be specified on the UE side rather than on the RIS side. However, in some scenarios, the UE may not be able to perform the combined Fig. 9 and Fig.10 UL beam adaptation is described, such as when the UE is unable to calculate or estimate the direction of its UE UL beam, or the UE is configured to follow the specified UL beam management procedure without specifying additional beam refinement.

[0123] Various aspects presented herein may enable a RIS to perform RIS beam adaptation for RIS UL beam refinement such that beam correspondence may be maintained between a UE and a base station without specifying that the UE perform UE UL beam adaptation / management. For example, in one example, the RIS may be configured to optimize its control voltage to maintain best UL quality or maintain UL quality above a quality threshold.

[0124] Fig.111 is a communication flow 1100 illustrating an example of a RIS performing RIS beam adaptation for beam refinement according to various aspects of the present disclosure. The numbers associated with the communication flow 1100 do not specify a particular time sequence and are merely used as a reference for the communication flow 1100. Various aspects presented herein may enable the RIS to maintain beam correspondence between a base station and a UE based on RIS training / adaptation.

[0125] At 1120 , base station 1102 may send a DL RS set to RIS 1106 , which will be forwarded to UE 1104 .

[0126] At 1122, the RIS 1106 may forward the DL RS to the UE based on the first DL control voltage (eg, based on the first reflection angle or the first RIS DL beam).

[0127] At 1124, after receiving the DL RS from the RIS 1106, the UE 1104 may measure the DL RS using the UE receive beam set. For example, the UE 1104 may measure the RSRP or signal to interference plus noise ratio (SINR) of the DL RS using the UE receive beam set.

[0128] At 1126, the UE 1104 may select one or more SRS beams (e.g., UL beams for transmitting SRS) for communicating with the base station 1102 via the RIS 1106. For example, the UE 1104 may measure the RSRP of the DL RS transmitted / reflected from the RIS 1106, and the UE 1104 may select the SRS beam corresponding to the UE receive beam having the highest RSRP measurement.

[0129] At 1128, after selecting an SRS beam based on the DL RS measurement, the UE 1104 may use the selected SRS beam for RIS training to repeat the SRS transmission to the RIS 1106. In one example, the UE 1104 may be specified to maintain the same SRS beam for repeatedly transmitting the SRS for a specified duration during the RIS training phase. Therefore, the UE 1104 may be configured to report to the base station 1102, the location server, or the LMF its capabilities in terms of the longest duration for which the SRS beam can be maintained, where the capabilities may be in units of time slots (e.g., X time slots). In addition, the repetition factor for repeatedly transmitting the SRS may be determined by the UE 1104, the base station 1102, the location server, and / or the LMF based on the capabilities of the UE and / or the RIS (e.g., the RIS may be able to support only a limited number of control voltages).

[0130] At 1130, after receiving the SRS transmission from UE 1104, for each SRS reflection (e.g., a reflection of the SRS transmission received from UE 1104 to base station 1102), RIS 1106 may use a different control voltage (e.g., a UL control voltage) to achieve a different reflection coefficient (e.g., reflecting the SRS transmission toward base station 1102 at a different reflection angle).

[0131] At 1132, based on the received reflected SRS transmission, the base station 1102 may evaluate which RIS UL beam provides the best / highest UL quality based on beam measurements (e.g., RSRP or SINR measurements), and the base station may select the best RIS UL beam that provides the best / highest UL quality and indicate the selected RIS UL beam to RIS 1106.

[0132] At 1132, in response to the RIS UL beam indication from the base station 1102, the RIS 1106 may update a pair of control voltage sets that are mapped to the corresponding beam correspondence. For example, the RIS 1106 may update the pair of control voltage sets between the base station 1102 and the UE 1104 based on the DL control voltage (e.g., obtained at 1122) and the control voltage associated with the RIS UL beam (e.g., obtained at 1130).

[0133] At 1134, beam correspondence between base station 1102 and UE 1104 may be maintained by adjusting control voltages at the RIS for RIS reflection. For example, RIS 1106 may forward subsequent transmissions between base station 1102 and UE 1104 based on the updated control voltage pair to maintain beam correspondence.

[0134] In some examples, the RIS may include several default control voltage sets, and the base station may trigger RIS training / adaptation through cable-based control or over-the-air (OTA) control (e.g., such as DCI-based triggering). In another example, the UE may request RIS training / adaptation on demand (e.g., the training / adaptation is triggered by the UE).

[0135] Fig.12 1200 is a flow chart of a method of wireless communication. The method may be performed by a UE (e.g., UE 104, 404, 804, 904, 1004, 1104; device 1404). The method may enable the UE to maintain beam correspondence with a base station via a RIS having a limited number of control voltage sets (e.g., having a pair of control voltage sets).

[0136] At 1202, the UE may obtain an indication of beam pattern information for a DL beam set for a network entity, wherein the DL beam set is associated with a RIS, such as in conjunction with Figures 9 and 10 For example, in Fig. 9 At 920, UE 904 may receive beam pattern information 908 associated with a RISDL beam set from base station 902. Receipt of an indication of the beam pattern information may be performed by, for example, Fig.14 The RIS communication component 198, cellular baseband processor 1424 and / or transceiver 1422 of the device 1404 are executed.

[0137] In one example, at 1204, to obtain an indication of the beam pattern information, the UE may receive, from the network entity via the RIS, the indication of the beam pattern information for the DL beam set associated with the RIS, such as in conjunction with Figures 9 and 10 For example, in Fig. 9 At 920, UE 904 may receive beam pattern information 908 associated with a RISDL beam set from base station 902. Receipt of an indication of the beam pattern information may be performed by, for example, RIS communication component 198, cellular baseband processor 1424, and / or transceiver 1422 of device 1404 in the figure.

[0138] At 1206, the UE may calculate a direction for transmitting the UL beam set based on the beam pattern information, wherein based on the calculated direction, the first transmit angle of the UL beam set is adjusted to be approximately aligned with the second transmit angle of the DL beam set from the RIS, such as in combination with Figures 9 and 10 For example, in Fig. 9 At 922, the UE 904 may calculate a direction 912 for transmitting the UL beam set 914 based on the beam pattern information 908 and the measurement for the RISDL beam set 910. The calculation of the direction may be performed by, for example Fig.14 The RIS communication component 198, the cellular baseband processor 1424 and / or the transceiver 1422 of the device 1404 in the embodiment of the present invention are executed. In such examples, the beam pattern information includes: a first beam pattern of a PRS, a second beam pattern of a SSB, a third beam pattern of a CSI-RS, or a combination thereof. In another example, the direction is calculated based on calculating the RSRP of the DL beam set or using an Rx digital beamforming-based method to calculate the direction for sending the UL beam set.

[0139] At 1208, the UE may indicate a method for calculating the direction for sending the UL beam set to the network entity, wherein the method for calculating the direction is based on the capabilities of the UE, such as in conjunction with Figures 9 and 10 For example, in Fig. 9 At 928, UE 904 may send an indication of a method for calculating direction 912 to base station 902. The indication of the method for calculating direction may be provided by, for example Fig.14 The RIS communication component 198, cellular baseband processor 1424 and / or transceiver 1422 of the device 1404 are executed.

[0140] In another example, at 1210, the UE may measure the RSRP of each DL beam in the set of DL beams from the RIS, and send a report of the RSRP measurement for each DL beam in the set of DL beams to the network entity, such as in conjunction with Figures 9 and 10 For example, in Fig.10 At 1020, UE 1004 may measure the RSRP of RISDL beam set 1010. The measurement of RSRP may be performed by, for example Fig.14 The RIS communication component 198, cellular baseband processor 1424 and / or transceiver 1422 of the device 1404 are executed.

[0141] At 1212, the UE may receive second information from the network entity indicating a difference between the angle of the DL beam set from the RIS and the AoD of the UE, such as in conjunction with Figures 9 and 10 For example, in Fig.10 At 1020, UE 1004 may receive an angle difference 1012 indication from base station 1002 indicating a difference between an angle of RISDL beam set 1010 and an AoD of UE 1004. The reception of the second information may be performed by, for example Fig.14 The RIS communication component 198, the cellular baseband processor 1424 and / or the transceiver 1422 of the device 1404 in the embodiment of the present invention are performed. In such examples, based on the difference, the first transmit angle of the UL beam set is adjusted to be approximately aligned with the second transmit angle of the DL beam set from the RIS.

[0142] At 1214, the UE may adjust a first transmit angle of a UL beam set based on the beam pattern information and the measurement for the DL beam set, wherein the first transmit angle of the UL beam set is adjusted to be approximately aligned with a second transmit angle of the DL beam set from the RIS, such as in combination with Figures 9 and 10 For example, in Fig. 9 At 924, the UE 904 may adjust the Tx angle of the UL beam set 914 based on the beam pattern information 908 (e.g., based on the calculated direction 912, the Tx angle of the UL beam set 914 is adjusted to be approximately aligned with the transmit angle of the RISDL beam set 910). The adjustment of the transmit angle may be performed by, for example Fig.14 The RIS communication component 198, cellular baseband processor 1424 and / or transceiver 1422 of the device 1404 are executed.

[0143] At 1216, the UE may send the UL beam set to the network entity via the RIS based on the adjusted first transmission angle, such as in combination with Figures 9 and 10 For example, in Fig. 9 At 926, UE 904 may transmit a signal at the adjusted Tx angle via UL beam set 914. Receipt of an indication of beam pattern information may be performed by, for example Fig.14 The RIS communication component 198, cellular baseband processor 1424 and / or transceiver 1422 of the device 1404 are executed.

[0144] Fig.13 1300 is a flow chart of a method of wireless communication. The method may be performed by a UE (e.g., UE 104, 404, 804, 904, 1004, 1104; device 1404). The method may enable the UE to maintain beam correspondence with a base station via a RIS having a limited number of control voltage sets (e.g., having a pair of control voltage sets).

[0145] At 1302, the UE may obtain an indication of beam pattern information for a DL beam set for a network entity, wherein the DL beam set is associated with a RIS, such as in conjunction with Figures 9 and 10 For example, in Fig. 9 At 920, UE 904 may receive beam pattern information 908 associated with a RISDL beam set from base station 902. Receipt of an indication of the beam pattern information may be performed by, for example, Fig.14 The RIS communication component 198, cellular baseband processor 1424 and / or transceiver 1422 of the device 1404 are executed.

[0146] At 1314, the UE may adjust a first transmit angle of a UL beam set based on the beam pattern information and the measurement for the DL beam set, wherein the first transmit angle of the UL beam set is adjusted to be approximately aligned with a second transmit angle of the DL beam set from the RIS, such as in combination with Figures 9 and 10 For example, in Fig. 9 At 924, the UE 904 may adjust the Tx angle of the UL beam set 914 based on the beam pattern information 908 (e.g., based on the calculated direction 912, the Tx angle of the UL beam set 914 is adjusted to be approximately aligned with the transmit angle of the RISDL beam set 910). The adjustment of the transmit angle may be performed by, for example Fig.14 The RIS communication component 198, cellular baseband processor 1424 and / or transceiver 1422 of the device 1404 are executed.

[0147] At 1316, the UE may send the UL beam set to the network entity via the RIS based on the adjusted first transmission angle, such as in combination with Figures 9 and 10 For example, in Fig. 9 At 926, UE 904 may transmit a signal at the adjusted Tx angle via UL beam set 914. Receipt of an indication of beam pattern information may be performed by, for example Fig.14 The RIS communication component 198, cellular baseband processor 1424 and / or transceiver 1422 of the device 1404 are executed.

[0148] In one example, to obtain an indication of the beam pattern information, the UE may receive the indication of the beam pattern information for the DL beam set associated with the RIS from the network entity via the RIS, such as in conjunction with Figures 9 and 10 For example, in Fig. 9 At 920, UE 904 may receive beam pattern information 908 associated with a RISDL beam set from base station 902. Receipt of an indication of the beam pattern information may be performed by, for example, RIS communication component 198, cellular baseband processor 1424, and / or transceiver 1422 of device 1404 in the figure.

[0149] In another example, the UE may calculate a direction for transmitting the UL beam set based on the beam pattern information, wherein based on the calculated direction, the first transmit angle of the UL beam set is adjusted to be approximately aligned with the second transmit angle of the DL beam set from the RIS, such as in combination with Figures 9 and 10 For example, in Fig. 9 At 922, the UE 904 may calculate a direction 912 for transmitting the UL beam set 914 based on the beam pattern information 908 and the measurement for the RISDL beam set 910. The calculation of the direction may be performed by, for example Fig.14 The RIS communication component 198, the cellular baseband processor 1424 and / or the transceiver 1422 of the device 1404 in the embodiment of the present invention are executed. In such examples, the beam pattern information includes: a first beam pattern of a PRS, a second beam pattern of a SSB, a third beam pattern of a CSI-RS, or a combination thereof. In another example, the direction is calculated based on calculating the RSRP of the DL beam set or using an Rx digital beamforming-based method to calculate the direction for sending the UL beam set.

[0150] In another example, the UE may indicate a method for calculating the direction for sending the UL beam set to the network entity, wherein the method for calculating the direction is based on the capabilities of the UE, such as in combination with Figures 9 and 10 For example, in Fig. 9 At 928, UE 904 may send an indication of a method for calculating direction 912 to base station 902. The indication of the method for calculating direction may be provided by, for example Fig.14The RIS communication component 198, cellular baseband processor 1424 and / or transceiver 1422 of the device 1404 are executed.

[0151] In another example, the UE may measure the RSRP of each DL beam in the DL beam set from the RIS, and send a report of the RSRP measurement for each DL beam in the DL beam set to the network entity, such as in conjunction with Figures 9 and 10 For example, in Fig.10 At 1020, UE 1004 may measure the RSRP of RISDL beam set 1010. The measurement of RSRP may be performed by, for example Fig.14 The RIS communication component 198, cellular baseband processor 1424 and / or transceiver 1422 of the device 1404 are executed.

[0152] In another example, the UE may receive second information from the network entity indicating a difference between the angle of the DL beam set from the RIS and the AoD of the UE, such as in conjunction with Figures 9 and 10 For example, in Fig.10 At 1020, UE 1004 may receive an angle difference 1012 indication from base station 1002 indicating a difference between an angle of RIS DL beam set 1010 and an AoD of UE 1004. Receipt of the second information may be performed by, for example Fig.14 The RIS communication component 198, the cellular baseband processor 1424 and / or the transceiver 1422 of the device 1404 in the embodiment of the present invention are performed. In such examples, based on the difference, the first transmit angle of the UL beam set is adjusted to be approximately aligned with the second transmit angle of the DL beam set from the RIS.

[0153] Fig.141400 is a diagram illustrating an example of a hardware implementation for an apparatus 1404. The apparatus 1404 may be a UE, a component of a UE, or may implement UE functionality. In some aspects, the apparatus 1404 may include a cellular baseband processor 1424 (also referred to as a modem) coupled to one or more transceivers 1422 (e.g., a cellular RF transceiver). The cellular baseband processor 1424 may include on-chip memory 1424'. In some aspects, the apparatus 1404 may also include one or more subscriber identity module (SIM) cards 1420 and an application processor 1406 coupled to a secure digital (SD) card 1408 and a screen 1410. The application processor 1406 may include on-chip memory 1406'. In some aspects, the device 1404 may also include a Bluetooth module 1412, a WLAN module 1414, an SPS module 1416 (e.g., a GNSS module), one or more sensor modules 1418 (e.g., an atmospheric pressure sensor / altimeter; a motion sensor (such as an inertial management unit (IMU), a gyroscope and / or an accelerometer, a magnetometer, audio, and / or other technologies for positioning), an additional memory module 1426, a power source 1430, and / or a camera 1432. The Bluetooth module 1412, the WLAN module 1414, and the SPS module 1416 may include an on-chip transceiver (TRX) (or in some cases, only a receiver (RX)). The Bluetooth module 1412, the WLAN module 1414, and the SPS module 1416 may include their own dedicated antennas and / or communicate using an antenna 1480. The cellular baseband processor 1424 communicates with the UE 104 and / or the UE 104 through the transceiver 1422 via one or more antennas 1480. Communicate with the RU associated with the network entity 1402. The cellular baseband processor 1424 and the application processor 1406 may each include a computer-readable medium / memory 1424', 1406', respectively. The additional memory module 1426 may also be considered a computer-readable medium / memory. Each computer-readable medium / memory 1424', 1406', 1426 may be non-transitory. The cellular baseband processor 1424 and the application processor 1406 are each responsible for general processing, including executing software stored on the computer-readable medium / memory. The software, when executed by the cellular baseband processor 1424 / application processor 1406, enables the cellular baseband processor 1424 / application processor 1406 to perform the various functions described above. The computer-readable medium / memory may also be used to store data manipulated by the cellular baseband processor 1424 / application processor 1406 when executing the software. The cellular baseband processor 1424 / application processor 1406 may be a UE 350 and may include memory 360 and / or at least one of TX processor 368, RX processor 356, and controller / processor 359.In one configuration, the device 1404 may be a processor chip (modem and / or applications) and include only the cellular baseband processor 1424 and / or the application processor 1406, and in another configuration, the device 1404 may be an entire UE (eg, see. Figure 3 350) and includes additional modules of device 1404.

[0154] As discussed above, the RIS communication component 198 may be configured to obtain an indication of beam pattern information for a DL beam set for a network entity, wherein the DL beam set is associated with the RIS. The RIS communication component 198 may also be configured to adjust a first transmit angle of a UL beam set based on the beam pattern information and measurements for the DL beam set, wherein the first transmit angle of the UL beam set is adjusted to be approximately aligned with a second transmit angle of the DL beam set from the RIS. The RIS communication component 198 may also be configured to transmit the UL beam set to the network entity via the RIS based on the adjusted first transmit angle. The RIS communication component 198 may be within the cellular baseband processor 1424, the application processor 1406, or both the cellular baseband processor 1424 and the application processor 1406. The RIS communication component 198 may be one or more hardware components specifically configured to perform the process / algorithm, implemented by one or more processors configured to perform the process / algorithm, stored in a computer-readable medium for implementation by one or more processors, or some combination of the foregoing. As shown, the device 1404 may include a variety of components configured for various functions. In one configuration, the device 1404 (and in particular the cellular baseband processor 1424 and / or the application processor 1406) may include a component for obtaining an indication of beam pattern information for a DL beam set for a network entity, wherein the DL beam set is associated with a RIS. The device 1404 may also include a component for adjusting a first transmit angle of a UL beam set based on the beam pattern information and measurements for the DL beam set, wherein the first transmit angle of the UL beam set is adjusted to be approximately aligned with a second transmit angle of the DL beam set from the RIS. The device 1404 may also include a component for transmitting the UL beam set to the network entity via the RIS based on the adjusted first transmit angle.

[0155] In one configuration, to obtain the indication of the beam pattern information, the apparatus 1404 is configured to receive, from the network entity via the RIS, the indication of the beam pattern information for the DL beam set associated with the RIS.

[0156] In another configuration, the device 1404 may also include a component for calculating a direction for transmitting the UL beam set based on the beam pattern information, and wherein based on the calculated direction, the first transmit angle of the UL beam set is adjusted to be approximately aligned with the second transmit angle of the DL beam set from the RIS. In such a configuration, the beam pattern information includes: a first beam pattern for PRS, a second beam pattern for SSB, a third beam pattern for CSI-RS, or a combination thereof. In another configuration, the direction for transmitting the UL beam set is calculated based on calculating the RSRP of the DL beam set or using an Rx digital beamforming-based method to calculate the direction.

[0157] In another configuration, the apparatus 1404 may further include means for instructing a method of calculating the direction for transmitting the UL beam set to the network entity, wherein the method of calculating the direction is based on a capability of the UE.

[0158] In another configuration, to obtain an indication of the beam pattern information, the apparatus 1404 is configured to receive, from the network entity, second information indicating a difference between an angle of the DL beam set from the RIS and the AoD of the UE.

[0159] In another configuration, based on the difference, the first transmit angle of the UL set of beams is adjusted to be approximately aligned with the second transmit angle of the DL set of beams from the RIS.

[0160] In another configuration, the apparatus 1404 may further include means for measuring the RSRP of each DL beam in the set of DL beams from the RIS and means for sending a report of the RSRP measurement for each DL beam in the set of DL beams to the network entity.

[0161] These components may be the RIS communication component 198 of the device 1404 configured to perform the functions recited by the components. As described above, the device 1404 may include the TX processor 368, the RX processor 356, and the controller / processor 359. Thus, in one configuration, these components may be the TX processor 368, the RX processor 356, and / or the controller / processor 359 configured to perform the functions recited by the components.

[0162] Fig.15 1500 is a flow chart of a method of wireless communication. The method may be performed by a base station (e.g., base station 102, 902, 1002, 1102; network entity 1702). The method may enable the base station to maintain beam correspondence with a UE via a RIS having a limited number of control voltage sets (e.g., having a pair of control voltage sets).

[0163] At 1502, the base station may receive a report of RSRP measurements for each DL beam in the set of DL beams from the RIS, wherein the report is received from the UE, and the base station may calculate the difference between the angle of the set of DL beams from the RIS and the AoD of the UE based on the RSRP measurements for each DL beam in the set of DL beams from the RIS, such as in combination with Fig.10 For example, in Fig.10 At 1022 and 1024 of FIG. 1 , the base station 1002 may receive an RSRP measurement report for the RISDL beam set 1010 from the UE 1004, and the base station 1002 may derive an angle difference 1012 between the RISDL beam 1010 and the AoD of the UE 1004 based on the RSRP measurement. The reception of the RSRP measurement and / or the calculation of the difference between the angles may be performed by, for example Fig.17 The RIS communication component 199 and / or the transceiver 1746 of the network entity 1702 may be implemented.

[0164] At 1504, the base station may send an indication of beam pattern information for a DL beam set to the UE, wherein the DL beam set is associated with the RIS, such as in conjunction with Fig. 9 and Fig.10 For example, in Fig. 9 At 908, the base station 1002 may send beam pattern information 908 for the RISDL beam set to the UE 904. The sending of the indication of the beam pattern information may be performed by, for example, Fig.17 The RIS communication component 199 and / or the transceiver 1746 of the network entity 1702 in the embodiment of the present invention are executed. In one example, the beam pattern information includes: a first beam pattern of a PRS, a second beam pattern of a SSB, a third beam pattern of a CSI-RS, or a combination thereof.

[0165] At 1506, the base station may send second information indicating a difference between the angle of the DL beam set from the RIS and the AoD of the UE, wherein the second information is sent to the UE, such as in conjunction with Fig. 9 and Fig.10 For example, in Fig.10 At 1012, base station 1002 may send to UE 1004 an angle difference 1012 between RISDL beam 1010 and the AoD of UE 1004. The sending of information indicating the difference between the angles may be performed by, for example Fig.17 The RIS communication component 199 and / or the transceiver 1746 of the network entity 1702 may be implemented.

[0166] At 1508, the base station may receive a second indication indicating a method for calculating a direction for transmitting the UL beam set, wherein the second indication is received from the UE, wherein one or more parameters in the beam pattern information are determined based on the method for calculating the direction, such as in combination with Fig. 9 For example, in Fig. 9 At 928, base station 902 may receive an indication of a method for calculating direction 912 from UE 904. Receipt of a second indication indicating a method for calculating direction may be performed by, for example Fig.17 The RIS communication component 199 and / or the transceiver 1746 of the network entity 1702 may be implemented.

[0167] At 1510, the base station may receive a UL beam set from the UE based on the adjusted transmit angle derived from the beam pattern information and measurements for the DL beam set, wherein the UL beam set is received from the UE via the RIS, such as in conjunction with Fig. 9 and Fig.10 For example, in Fig.10 At 926, the base station 1002 may receive a signal from the UE 904 via the UL beam set 914 at the adjusted Tx angle. The reception of the UL beam set may be performed by, for example Fig.17 The RIS communication component 199 and / or the transceiver 1746 of the network entity 1702 may be implemented.

[0168] Fig.16 1600 is a flow chart of a method of wireless communication. The method may be performed by a base station (e.g., base station 102, 902, 1002, 1102; network entity 1702). The method may enable the base station to maintain beam correspondence with a UE via a RIS having a limited number of control voltage sets (e.g., having a pair of control voltage sets).

[0169] At 1604, the base station may send an indication of beam pattern information for a DL beam set to the UE, wherein the DL beam set is associated with the RIS, such as in conjunction with Fig. 9 and Fig.10 For example, in Fig. 9 At 908, the base station 1002 may send beam pattern information 908 for the RISDL beam set to the UE 904. The sending of the indication of the beam pattern information may be performed by, for example, Fig.17 The RIS communication component 199 and / or the transceiver 1746 of the network entity 1702 in the embodiment of the present invention are executed. In one example, the beam pattern information includes: a first beam pattern of a PRS, a second beam pattern of a SSB, a third beam pattern of a CSI-RS, or a combination thereof.

[0170] At 1610, the base station may receive a UL beam set from the UE based on the adjusted transmit angle derived from the beam pattern information and measurements for the DL beam set, wherein the UL beam set is received from the UE via the RIS, such as in conjunction with Fig. 9 and Fig.10 For example, in Fig.10 At 926, the base station 1002 may receive a signal from the UE 904 via the UL beam set 914 at the adjusted Tx angle. The reception of the UL beam set may be performed by, for example Fig.17 The RIS communication component 199 and / or the transceiver 1746 of the network entity 1702 may be implemented.

[0171] In one example, the base station may receive a report of RSRP measurements for each DL beam in the set of DL beams from the RIS, wherein the report is received from the UE, and the base station may calculate the difference between the angle of the set of DL beams from the RIS and the AoD of the UE based on the RSRP measurements for each DL beam in the set of DL beams from the RIS, such as in combination with Fig.10 For example, in Fig.10 At 1022 and 1024 of FIG. 1 , the base station 1002 may receive an RSRP measurement report for the RISDL beam set 1010 from the UE 1004, and the base station 1002 may derive an angle difference 1012 between the RISDL beam 1010 and the AoD of the UE 1004 based on the RSRP measurement. The reception of the RSRP measurement and / or the calculation of the difference between the angles may be performed by, for example Fig.17 The RIS communication component 199 and / or the transceiver 1746 of the network entity 1702 may be implemented.

[0172] In another example, the base station may send second information indicating a difference between the angle of the DL beam set from the RIS and the AoD of the UE, wherein the second information is sent to the UE, such as in conjunction with Fig. 9 and Fig.10 For example, in Fig.10 At 1012, base station 1002 may send to UE 1004 an angle difference 1012 between RISDL beam 1010 and the AoD of UE 1004. The sending of information indicating the difference between the angles may be performed by, for example Fig.17 The RIS communication component 199 and / or the transceiver 1746 of the network entity 1702 may be implemented.

[0173] In another example, the base station may receive a second indication indicating a method for calculating a direction for transmitting the UL beam set, wherein the second indication is received from the UE, wherein one or more parameters in the beam pattern information are determined based on the method for calculating the direction, such as in combination with Fig. 9 For example, in Fig. 9 At 928, base station 902 may receive an indication of a method for calculating direction 912 from UE 904. Receipt of a second indication indicating a method for calculating direction may be performed by, for example Fig.17 The RIS communication component 199 and / or the transceiver 1746 of the network entity 1702 may be implemented.

[0174] Fig.171700 is a diagram illustrating an example of a hardware implementation for a network entity 1702. The network entity 1702 may be a BS, a component of a BS, or may implement BS functionality. The network entity 1702 may include at least one of a CU 1710, a DU 1730, or a RU 1740. For example, depending on the layer functionality handled by the RIS communication component 199, the network entity 1702 may include a CU 1710; both the CU 1710 and the DU 1730; each of the CU 1710, the DU 1730, and the RU 1740; the DU 1730; both the DU 1730 and the RU 1740; or the RU 1740. The CU 1710 may include a CU processor 1712. The CU processor 1712 may include an on-chip memory 1712'. In some aspects, the CU 1710 may also include an additional memory module 1714 and a communication interface 1718. CU 1710 communicates with DU 1730 via a midhaul link such as an F1 interface. DU 1730 may include a DU processor 1732. DU processor 1732 may include on-chip memory 1732'. In some aspects, DU 1730 may also include an additional memory module 1734 and a communication interface 1738. DU 1730 communicates with RU 1740 via a fronthaul link. RU 1740 may include a RU processor 1742. RU processor 1742 may include on-chip memory 1742'. In some aspects, RU 1740 may also include an additional memory module 1744, one or more transceivers 1746, an antenna 1780, and a communication interface 1748. RU 1740 communicates with UE 104. On-chip memory 1712', 1732', 1742' and additional memory modules 1714, 1734, 1744 may each be considered a computer-readable medium / memory. Each computer readable medium / memory may be non-transitory. Each of processors 1712, 1732, 1742 is responsible for general processing, including executing software stored on the computer readable medium / memory. The software, when executed by the corresponding processor, causes the processor to perform the various functions described above. The computer readable medium / memory may also be used to store data manipulated by the processor when executing the software.

[0175] As discussed above, the RIS communication component 199 may be configured to send an indication of beam pattern information for a DL beam set to a UE, wherein the DL beam set is associated with the RIS. The RIS communication component 199 may also be configured to receive a UL beam set from the UE based on the adjusted transmit angle derived from the beam pattern information and measurements for the DL beam set, wherein the UL beam set is received from the UE via the RIS. The RIS communication component 199 may be within one or more processors of one or more of the CU 1710, DU 1730, and RU 1740. The RIS communication component 199 may be one or more hardware components specifically configured to perform the process / algorithm, implemented by one or more processors configured to perform the process / algorithm, stored in a computer-readable medium for implementation by one or more processors, or some combination of the foregoing. The network entity 1702 may include a variety of components configured for various functions. In one configuration, the network entity 1702 may include means for sending an indication of beam pattern information for a DL beam set to a UE, wherein the DL beam set is associated with a RIS. The network entity 1702 may also include means for receiving a UL beam set from the UE based on an adjusted transmit angle derived from the beam pattern information for the DL beam set and measurements, wherein the UL beam set is received from the UE via the RIS.

[0176] In one configuration, the beam pattern information includes: a first beam pattern for PRS, a second beam pattern for SSB, a third beam pattern for CSI-RS, or a combination thereof.

[0177] In another configuration, the network entity 1702 may also include a component for receiving a second indication indicating a method for calculating a direction for sending the UL beam set, wherein the second indication is received from the UE, wherein one or more parameters in the beam pattern information are determined based on the method for calculating the direction.

[0178] In another configuration, the means for sending an indication of the beam pattern information further comprises configuring the network entity 1702 to send second information indicating a difference between an angle of the DL beam set from the RIS and the AoD of the UE, wherein the second information is sent to the UE.

[0179] In another configuration, the network entity 1702 may also include a component for receiving a report of RSRP measurement for each DL beam in the DL beam set from the RIS, wherein the report is received from the UE; and a component for calculating the difference between the angle of the DL beam set from the RIS and the AoD of the UE based on the RSRP measurement for each DL beam in the DL beam set from the RIS.

[0180] These components may be the RIS communication components 199 of the network entity 1702 configured to perform the functions recited by the components. As described above, the network entity 1702 may include the TX processor 316, the RX processor 370, and the controller / processor 375. Thus, in one configuration, these components may be the TX processor 316, the RX processor 370, and / or the controller / processor 375 configured to perform the functions recited by the components.

[0181] Fig.18 1800 is a flow chart of a method of wireless communication. The method may be performed by a RIS (eg, RIS 103, 906, 1006, 1106; device 1904). The method may enable the RIS to maintain beam correspondence between a base station and a UE using a limited number of control voltage sets.

[0182] At 1802, the RIS may receive a plurality of SRS transmissions from a UE via at least one UE UL beam, such as in combination with Fig.11 For example, in Fig.11 At 1128, RIS 1106 may receive an SRS transmission from UE 1104. Reception of the SRS transmission may be performed by, for example Fig.19 The RIS communication component 197, cellular baseband processor 1924 and / or transceiver 1922 of the device 1904 are executed.

[0183] At 1804, the RIS may forward the plurality of SRS transmissions to a network entity via a RIS UL beam set, wherein each RIS UL beam in the RIS UL beam set is associated with one UL control voltage in a UL control voltage set, and each UL control voltage in the UL control voltage set is associated with a reflection angle of the at least one UE UL beam, such as in combination with Fig.11 For example, in Fig.11 At 1130, RIS 1106 may forward multiple SRS transmissions to base station 1102 via the RIS UL beam set. The forwarding of the SRS transmissions may be performed by, for example, Fig.19 The RIS communication component 197, cellular baseband processor 1924 and / or transceiver 1922 of the device 1904 are executed.

[0184] At 1806, the RIS may receive from the network entity an indication of a RIS UL beam from the RIS UL beam set, wherein the RIS UL beam is selected from the RIS UL beam set based on one or more measurements associated with the plurality of SRS transmissions, such as in conjunction with Fig.11 For example, in Fig.11At 1132, RIS 1106 may receive a RIS UL beam indication from base station 1102. Receipt of the indication may be performed by, for example, Fig.19 The RIS communication component 197, cellular baseband processor 1924 and / or transceiver 1922 of the device 1904 are executed.

[0185] At 1808, the RIS may forward subsequent communications between the UE and the network entity based on a control voltage pair including a DL control voltage and a UL control voltage from the UL control voltage set corresponding to the RIS UL beam indicated by the network entity, such as in combination with Fig.11 For example, in Fig.11 At 1134, RIS 1106 may forward subsequent transmissions between base station 1102 and UE 1104 based on the updated control voltage pair. Forwarding of communications may be performed by, for example, Fig.19 The RIS communication component 197, cellular baseband processor 1924 and / or transceiver 1922 of the device 1904 are executed.

[0186] In one example, the RIS may receive a plurality of DL RS transmissions from a network entity, and the RIS may forward the plurality of DL RS transmissions to the UE using the DL control voltage, and wherein the at least one UE UL beam is determined based on a measurement set associated with the plurality of DL RS transmissions. In such examples, the measurement set associated with the plurality of DL RS transmissions includes RSRP or SINR of the DL RS transmissions.

[0187] In another example, the RIS UL beam indicated by the network entity is a beam with a best beam measurement or a most suitable beam measurement from the RIS UL beam set.

[0188] Fig.191900 is a diagram illustrating an example of a hardware implementation for an apparatus 1904. The apparatus 1904 may be a RIS, a component of a RIS, or may implement RIS functionality. In some aspects, the apparatus 1904 may include a cellular baseband processor 1924 (also referred to as a modem) coupled to one or more transceivers 1922 (e.g., a cellular RF transceiver). The cellular baseband processor 1924 may include on-chip memory 1924'. In some aspects, the apparatus 1904 may also include one or more subscriber identity module (SIM) cards 1920 and an application processor 1906 coupled to a secure digital (SD) card 1908 and a screen 1910. The application processor 1906 may include on-chip memory 1906'. In some aspects, the device 1904 may also include a Bluetooth module 1912, a WLAN module 1914, an SPS module 1916 (e.g., a GNSS module), one or more sensor modules 1918 (e.g., an atmospheric pressure sensor / altimeter; a motion sensor (such as an inertial management unit (IMU), a gyroscope and / or an accelerometer, a magnetometer, audio, and / or other technologies for positioning), an additional memory module 1926, a power source 1930, and / or a camera 1932. The Bluetooth module 1912, the WLAN module 1914, and the SPS module 1916 may include an on-chip transceiver (TRX) (or in some cases, only a receiver (RX)). The Bluetooth module 1912, the WLAN module 1914, and the SPS module 1916 may include their own dedicated antennas and / or communicate using antennas 1980. The cellular baseband processor 1924 communicates with the UE 104 and / or with the UE 104 through the transceiver 1922 via one or more antennas 1980. Communicate with RUs associated with the network entity 1902. The cellular baseband processor 1924 and the application processor 1906 may each include a computer-readable medium / memory 1924', 1906', respectively. The additional memory module 1926 may also be considered a computer-readable medium / memory. Each computer-readable medium / memory 1924', 1906', 1926 may be non-transitory. The cellular baseband processor 1924 and the application processor 1906 are each responsible for general processing, including executing software stored on a computer-readable medium / memory. The software, when executed by the cellular baseband processor 1924 / application processor 1906, enables the cellular baseband processor 1924 / application processor 1906 to perform the various functions described above. The computer-readable medium / memory may also be used to store data manipulated by the cellular baseband processor 1924 / application processor 1906 when executing the software. The cellular baseband processor 1924 / application processor 1906 may be a UE 350 and may include memory 360 and / or at least one of TX processor 368, RX processor 356, and controller / processor 359.In one configuration, the device 1904 may be a processor chip (modem and / or applications) and include only the cellular baseband processor 1924 and / or the application processor 1906, and in another configuration, the device 1904 may be an entire UE (eg, see. Figure 3 350) and includes additional modules of device 1904.

[0189] As discussed above, the RIS communication component 197 may be configured to receive a plurality of SRS transmissions from a UE via at least one UE UL beam. The RIS communication component 197 may also be configured to forward the plurality of SRS transmissions to a network entity via a RIS UL beam set, wherein each RIS UL beam in the RIS UL beam set is associated with one UL control voltage in a UL control voltage set, and wherein each UL control voltage in the UL control voltage set is associated with a reflection angle of the at least one UE UL beam. The RIS communication component 197 may also be configured to receive an indication from the network entity indicating a RIS UL beam from the RIS UL beam set, wherein the RIS UL beam is selected from the RIS UL beam set based on one or more measurements associated with the plurality of SRS transmissions. The RIS communication component 197 may also be configured to forward subsequent communications between the UE and the network entity based on a control voltage pair, the control voltage pair comprising a DL control voltage and a UL control voltage from the UL control voltage set corresponding to the RIS UL beam indicated by the network entity. The RIS communication component 197 may be within the cellular baseband processor 1924, the application processor 1906, or both the cellular baseband processor 1924 and the application processor 1906. The RIS communication component 197 may be one or more hardware components specifically configured to perform the process / algorithm, implemented by one or more processors configured to perform the process / algorithm, stored in a computer-readable medium for implementation by one or more processors, or some combination of the above. As shown, the device 1904 may include a variety of components configured for various functions. In one configuration, the device 1904 (and in particular the cellular baseband processor 1924 and / or the application processor 1906) may include a component for receiving a plurality of SRS transmissions from a UE via at least one UE UL beam. The device 1904 may also include a component for forwarding the plurality of SRS transmissions to a network entity via a RIS UL beam set, wherein each RIS UL beam in the RIS UL beam set is associated with one UL control voltage in a UL control voltage set, and wherein each UL control voltage in the UL control voltage set is associated with a reflection angle of the at least one UE UL beam. The apparatus 1904 may also include means for receiving, from the network entity, an indication of a RIS UL beam from the RIS UL beam set, wherein the RIS UL beam is selected from the RIS UL beam set based on one or more measurements associated with the plurality of SRS transmissions. The apparatus 1904 may also include means for forwarding subsequent communications between the UE and the network entity based on a control voltage pair, the control voltage pair comprising a DL control voltage and a UL control voltage from the UL control voltage set corresponding to the RIS UL beam indicated by the network entity.

[0190] In one configuration, the RIS may receive a plurality of DL RS transmissions from a network entity, and the RIS may forward the plurality of DL RS transmissions to the UE using the DL control voltage, and wherein the at least one UE UL beam is determined based on a measurement set associated with the plurality of DL RS transmissions. In such a configuration, the measurement set associated with the plurality of DL RS transmissions includes RSRP or SINR of the DL RS transmissions.

[0191] In another configuration, the RIS UL beam indicated by the network entity is the beam from the RIS UL beam set having the best beam measurement or the most suitable beam measurement.

[0192] These components may be the RIS communication component 197 of the device 1904 configured to perform the functions recited by the components. As described above, the device 1904 may include the TX processor 368, the RX processor 356, and the controller / processor 359. Thus, in one configuration, these components may be the TX processor 368, the RX processor 356, and / or the controller / processor 359 configured to perform the functions recited by the components.

[0193] It should be understood that the specific order or hierarchy of the blocks in the disclosed process / flowchart is merely an illustration of the exemplary method. It should be understood that the specific order or hierarchy of the blocks in the process / flowchart may be rearranged based on design preferences. Further, some blocks may be combined or omitted. The attached method claims provide the elements of the various blocks in a sample order, but are not limited to the specific order or hierarchy provided.

[0194] The foregoing description is provided to enable any person skilled in the art to practice the various aspects described herein. Various modifications to these aspects will be apparent to those skilled in the art, and the general principles defined herein can be applied to other aspects. Therefore, the claims are not limited to the various aspects described herein, but should be given the full scope consistent with the language claims. Unless otherwise specified, reference to an element in the singular form does not mean "one and only one", but "one or more". Terms such as "if", "when" and "while" do not mean a direct temporal relationship or reaction. That is, these phrases, such as "when ...", do not mean an immediate action in response to the occurrence of an action or during the occurrence of an action, but simply imply that if the conditions are met, then the action will occur, but no specific or immediate time limit is required for the occurrence of the action. The word "exemplary" is used herein to mean "used as an example, instance or illustration". Any aspect described as "exemplary" herein is not necessarily interpreted as being preferred or having advantages over other aspects. Unless otherwise specified, the term "some" refers to one or more. Combinations such as "at least one of A, B, or C", "one or more of A, B, or C", "at least one of A, B and C", "one or more of A, B, and C", and "A, B, C, or any combination thereof" include any combination of A, B, and / or C, which may include multiple A, multiple B, or multiple C. Specifically, combinations such as "at least one of A, B, or C", "one or more of A, B, or C", "at least one of A, B, and C", "one or more of A, B, and C", and "A, B, C, or any combination thereof" may be only A, only B, only C, A and B, A and C, B and C, or A and B and C, where any such combination may contain one or more members of A, B, or C. A set should be interpreted as a set of elements, where the number of elements is one or more. Thus, for a set of X, X will include one or more elements. If the first device receives data from the second device or sends data to the second device, the data may be directly received / sent between the first device and the second device, or indirectly received / sent between the first device and the second device through a collection of devices. All structural and functional equivalents of the elements throughout the various aspects described in this disclosure that are known or will later be known to a person of ordinary skill in the art are expressly incorporated herein by reference and are covered by the claims. In addition, nothing disclosed herein is intended to be dedicated to the public, regardless of whether such disclosure is explicitly stated in the claims. Words such as "module", "mechanism", "element", "device" cannot replace the word "component". Therefore, no claim element will be understood as a component plus function unless the element is explicitly stated using the phrase "component for..."

[0195] As used herein, the phrase "based on" should not be interpreted as referring to a closed set of information, one or more conditions, one or more factors, etc. In other words, the phrase "based on A" (where "A" can be information, conditions, factors, etc.) should be interpreted as "based at least on A" unless specifically stated differently.

[0196] The following aspects are merely illustrative and may be combined with other aspects or teachings described herein without limitation.

[0197] Aspect 1 is a method for wireless communication at a UE, the method comprising: obtaining an indication of beam pattern information for a DL beam set for a network entity, wherein the DL beam set is associated with a RIS; adjusting a first transmit angle of a UL beam set based on the beam pattern information and measurements for the DL beam set, wherein the first transmit angle of the UL beam set is adjusted to be approximately aligned with a second transmit angle of the DL beam set from the RIS; and sending the UL beam set to the network entity via the RIS based on the adjusted first transmit angle.

[0198] Aspect 2 is a method according to aspect 1, the method further comprising: receiving the indication of the beam pattern information for the DL beam set associated with the RIS from the network entity via the RIS.

[0199] Aspect 3 is a method according to any one of Aspects 1 or 2, the method further comprising: calculating a direction for transmitting the UL beam set based on the beam pattern information, and wherein based on the calculated direction, the first transmission angle of the UL beam set is adjusted to be approximately aligned with the second transmission angle of the DL beam set from the RIS.

[0200] Aspect 4 is a method according to aspect 3, wherein the beam pattern information includes: a first beam pattern of PRS, a second beam pattern of SSB, a third beam pattern of CSI-RS, or a combination thereof.

[0201] Aspect 5 is a method according to aspect 3, wherein the direction is calculated based on calculating the RSRP of the DL beam set or using a method based on Rx digital beamforming to calculate the direction for sending the UL beam set.

[0202] Aspect 6 is a method according to aspect 3, the method further comprising: indicating a method for calculating the direction for sending the UL beam set to the network entity, wherein the method for calculating the direction is based on the capability of the UE.

[0203] Aspect 7 is a method according to any one of aspects 1 to 6, the method further comprising: receiving second information indicating a difference between an angle of the DL beam set from the RIS and an AoD of the UE from the network entity.

[0204] Aspect 8 is a method according to aspect 7, wherein based on the difference, the first transmit angle of the UL beam set is adjusted to be approximately aligned with the second transmit angle of the DL beam set from the RIS.

[0205] Aspect 9 is a method according to Aspect 7, the method further comprising: measuring the RSRP of each DL beam in the DL beam set from the RIS; and sending a report of the RSRP measurement for each DL beam in the DL beam set to the network entity.

[0206] Aspect 10 is an apparatus for performing wireless communication at a UE, the apparatus comprising: a memory; and at least one processor, the at least one processor being coupled to the memory and being configured to implement any one of aspects 1 to 9 based at least in part on information stored in the memory.

[0207] Aspect 11 is the apparatus of aspect 10, further comprising at least one of a transceiver or an antenna coupled to the at least one processor.

[0208] Aspect 12 is an apparatus for wireless communication, the apparatus comprising means for implementing any one of aspects 1 to 9.

[0209] Aspect 13 is a computer-readable medium (eg, non-transitory computer-readable medium) storing computer-executable code, wherein the code, when executed by a processor, causes the processor to implement any one of aspects 1 to 9.

[0210] Aspect 14 is a method for wireless communication at a base station, the method comprising: sending an indication of beam pattern information for a DL beam set to a UE, wherein the DL beam set is associated with a RIS; and receiving a UL beam set from the UE based on an adjusted transmit angle derived from the beam pattern information and measurements for the DL beam set, wherein the UL beam set is received from the UE via the RIS.

[0211] Aspect 15 is a method according to aspect 14, wherein the beam pattern information includes: a first beam pattern of a PRS, a second beam pattern of an SSB, a third beam pattern of a CSI-RS, or a combination thereof.

[0212] Aspect 16 is a method according to Aspect 14 or 15, the method further comprising: receiving a second indication indicating a method for calculating a direction for sending the UL beam set, wherein the second indication is received from the UE, and wherein one or more parameters in the beam pattern information are determined based on the method for calculating the direction.

[0213] Aspect 17 is a method according to any one of aspects 14 to 16, the method further comprising: sending second information indicating a difference between an angle of the DL beam set from the RIS and an AoD of the UE, wherein the second information is sent to the UE.

[0214] Aspect 18 is a method according to Aspect 17, the method further comprising: receiving a report of RSRP measurement for each DL beam in the DL beam set from the RIS, wherein the report is received from the UE; and calculating the difference between the angle of the DL beam set from the RIS and the AoD of the UE based on the RSRP measurement for each DL beam in the DL beam set from the RIS.

[0215] Aspect 19 is an apparatus for performing wireless communications at a base station, the apparatus comprising: a memory; and at least one processor, the at least one processor being coupled to the memory and being configured to implement any one of Aspects 14 to 18 based at least in part on information stored in the memory.

[0216] Aspect 20 is the apparatus of aspect 19, further comprising at least one of a transceiver or an antenna coupled to the at least one processor.

[0217] Aspect 21 is an apparatus for wireless communication, the apparatus comprising means for implementing any one of aspects 14 to 18.

[0218] Aspect 22 is a computer-readable medium (eg, non-transitory computer-readable medium) storing computer-executable code, wherein the code, when executed by a processor, causes the processor to implement any one of aspects 14 to 18 .

[0219] Aspect 23 is a method for wireless communication at a RIS, the method comprising: receiving multiple SRS transmissions from a UE via at least one UE UL beam; forwarding the multiple SRS transmissions to a network entity via a RIS UL beam set, wherein each RIS UL beam in the RIS UL beam set is associated with one UL control voltage in a UL control voltage set, and wherein each UL control voltage in the UL control voltage set is associated with a reflection angle of the at least one UE UL beam; receiving an indication from the network entity indicating a RIS UL beam from the RIS UL beam set, wherein the RIS UL beam is selected from the RIS UL beam set based on one or more measurements associated with the multiple SRS transmissions; and forwarding subsequent communications between the UE and the network entity based on a control voltage pair, the control voltage pair comprising a DL control voltage and a UL control voltage from the UL control voltage set corresponding to the RIS UL beam indicated by the network entity.

[0220] Aspect 24 is a method according to Aspect 23, the method also including: receiving multiple DL RS transmissions from the network entity; and using the DL control voltage to forward the multiple DL RS transmissions to the UE, and wherein the at least one UE UL beam is determined based on a measurement set associated with the multiple DL RS transmissions.

[0221] Aspect 25 is a method according to aspect 24, wherein the measurement set associated with the plurality of DL RS transmissions comprises RSRP or SINR of the DL RS transmissions.

[0222] Aspect 26 is a method according to any one of aspects 23 to 25, wherein the RIS UL beam indicated by the network entity is a beam with the best beam measurement or the most suitable beam measurement from the RIS UL beam set.

[0223] Aspect 27 is an apparatus for wireless communication at a RIS, the apparatus comprising: a memory; and at least one processor, the at least one processor being coupled to the memory and being configured to implement any one of aspects 23 to 26 based at least in part on information stored in the memory.

[0224] Aspect 28 is the apparatus of aspect 27, further comprising at least one of a transceiver or an antenna coupled to the at least one processor.

[0225] Aspect 29 is an apparatus for wireless communication, the apparatus comprising means for implementing any one of aspects 23 to 26.

[0226] Aspect 30 is a computer-readable medium (eg, non-transitory computer-readable medium) storing computer-executable code, wherein the code, when executed by a processor, causes the processor to implement any one of aspects 23 to 26.

Claims

1. An apparatus for wireless communication at a user equipment (UE), the apparatus comprising: Memory; and at least one processor coupled to the memory and based at least in part on the information stored in the memory, the at least one processor configured to: obtaining an indication of beam pattern information for a downlink (DL) beam set for a network entity, wherein the DL beam set is associated with a reconfigurable intelligent surface (RIS); adjusting a first transmit angle of an uplink (UL) beam set based on the beam pattern information and measurements for the DL beam set, wherein the first transmit angle of the UL beam set is adjusted to be approximately aligned with a second transmit angle of the DL beam set from the RIS; and Based on the adjusted first transmission angle, the UL beam set is transmitted to the network entity via the RIS.

2. The apparatus of claim 1 , wherein to obtain the indication of the beam pattern information, the at least one processor is configured to: The indication of the beam pattern information for the DL beam set associated with the RIS is received from the network entity via the RIS.

3. The apparatus of claim 1 , wherein the at least one processor is further configured to: A direction for transmitting the UL beam set is calculated based on the beam pattern information, and wherein based on the calculated direction, the first transmit angle of the UL beam set is adjusted to be approximately aligned with the second transmit angle of the DL beam set from the RIS.

4. The apparatus according to claim 3, wherein the beam pattern information comprises: a first beam pattern of a positioning reference signal (PRS), a second beam pattern of a synchronization signal block (SSB), a third beam pattern of a channel state information reference signal (CSI-RS), or A combination of them.

5. The apparatus according to claim 3, wherein the direction for sending the UL beam set is calculated based on calculating a reference signal received power (RSRP) of the DL beam set or using a receive (Rx) digital beamforming-based method to calculate the direction.

6. The apparatus of claim 3, wherein the at least one processor is further configured to: Indicating a method of calculating the direction for sending the UL beam set to the network entity, wherein the method of calculating the direction is based on the capabilities of the UE.

7. The apparatus of claim 1 , wherein to obtain the indication of the beam pattern information, the at least one processor is further configured to: Second information indicating a difference between an angle of the set of DL beams from the RIS and an angle of departure (AoD) of the UE is received from the network entity.

8. The apparatus of claim 7, wherein based on the difference, the first transmit angle of the UL beam set is adjusted to be approximately aligned with the second transmit angle of the DL beam set from the RIS.

9. The apparatus of claim 7, wherein the at least one processor is further configured to: measuring a reference signal received power (RSRP) of each DL beam in the set of DL beams from the RIS; and A report of the RSRP measurement for each DL beam in the set of DL beams is sent to the network entity.

10. The apparatus of claim 1, further comprising at least one of a transceiver or an antenna coupled to the at least one processor.

11. A method of wireless communication at a user equipment (UE), the method comprising: obtaining an indication of beam pattern information for a downlink (DL) beam set for a network entity, wherein the DL beam set is associated with a reconfigurable intelligent surface (RIS); adjusting a first transmit angle of an uplink (UL) beam set based on the beam pattern information and measurements for the DL beam set, wherein the first transmit angle of the UL beam set is adjusted to be approximately aligned with a second transmit angle of the DL beam set from the RIS; and Based on the adjusted first transmission angle, the UL beam set is transmitted to the network entity via the RIS.

12. The method according to claim 11, further comprising: The indication of the beam pattern information for the DL beam set associated with the RIS is received from the network entity via the RIS.

13. The method according to claim 11, further comprising: A direction for transmitting the UL beam set is calculated based on the beam pattern information, and wherein based on the calculated direction, the first transmit angle of the UL beam set is adjusted to be approximately aligned with the second transmit angle of the DL beam set from the RIS.

14. The method of claim 13, wherein the beam pattern information comprises: a first beam pattern of a positioning reference signal (PRS), a second beam pattern of a synchronization signal block (SSB), a third beam pattern of a channel state information reference signal (CSI-RS), or A combination of them.

15. The method of claim 13, wherein the direction for sending the UL beam set is calculated based on calculating a reference signal received power (RSRP) of the DL beam set or using a receive (Rx) digital beamforming-based method to calculate the direction.

16. The method according to claim 13, further comprising: Indicating a method of calculating the direction for sending the UL beam set to the network entity, wherein the method of calculating the direction is based on the capabilities of the UE.

17. The method according to claim 11, further comprising: Second information indicating a difference between an angle of the set of DL beams from the RIS and an angle of departure (AoD) of the UE is received from the network entity.

18. The method of claim 17, wherein based on the difference, the first transmit angle of the UL beam set is adjusted to be approximately aligned with the second transmit angle of the DL beam set from the RIS.

19. The method according to claim 17, further comprising: measuring a reference signal received power (RSRP) of each DL beam in the set of DL beams from the RIS; as well as A report of the RSRP measurement for each DL beam in the set of DL beams is sent to the network entity.

20. An apparatus for wireless communication at a network entity, the apparatus comprising: Memory; and at least one processor coupled to the memory and based at least in part on the information stored in the memory, the at least one processor configured to: sending an indication of beam pattern information for a downlink (DL) beam set to a user equipment (UE), wherein the DL beam set is associated with a reconfigurable smart surface (RIS); and An uplink (UL) beam set is received from the UE based on the adjusted transmit angle derived from the beam pattern information and measurements for the DL beam set, wherein the UL beam set is received from the UE via the RIS.

21. The apparatus of claim 20, wherein the beam pattern information comprises: a first beam pattern of a positioning reference signal (PRS), a second beam pattern of a synchronization signal block (SSB), a third beam pattern of a channel state information reference signal (CSI-RS), or A combination of them.

22. The apparatus of claim 20, wherein the at least one processor is further configured to: Receive a second indication indicating a method for calculating a direction for transmitting the UL beam set, wherein the second indication is received from the UE, and wherein one or more parameters in the beam pattern information are determined based on the method for calculating the direction.

23. The apparatus of claim 20, wherein to send the indication of the beam pattern information, the at least one processor is configured to: Second information is transmitted indicating a difference between an angle of the DL beam set from the RIS and an angle of departure (AoD) of the UE, wherein the second information is transmitted to the UE.

24. The apparatus of claim 23, wherein the at least one processor is further configured to: receiving a report of a reference signal received power (RSRP) measurement for each DL beam in the set of DL beams from the RIS, wherein the report is received from the UE; and The difference between the angle of the set of DL beams from the RIS and the AoD of the UE is calculated based on the RSRP measurement for each DL beam in the set of DL beams from the RIS.

25. The apparatus of claim 24, further comprising at least one of a transceiver or an antenna coupled to the at least one processor.

26. An apparatus for wireless communication at a reconfigurable smart surface (RIS), the apparatus comprising: Memory; and at least one processor coupled to the memory and based at least in part on the information stored in the memory, the at least one processor configured to: receiving a plurality of sounding reference signal (SRS) transmissions from a user equipment (UE) via at least one UE uplink (UL) beam; forwarding the plurality of SRS transmissions to a network entity via a RIS UL beam set, wherein each RIS UL beam in the set of RIS UL beams is associated with one UL control voltage in a set of UL control voltages, and wherein each UL control voltage in the set of UL control voltages is associated with a reflection angle of the at least one UE UL beam; receiving, from the network entity, an indication indicating a RIS UL beam from the set of RIS UL beams, wherein the RIS UL beam is selected from the set of RIS UL beams based on one or more measurements associated with the plurality of SRS transmissions; and Subsequent communications between the UE and the network entity are forwarded based on a control voltage pair including a downlink (DL) control voltage and an UL control voltage from the UL control voltage set corresponding to the RIS UL beam indicated by the network entity.

27. The apparatus of claim 26, wherein the at least one processor is further configured to: receiving a plurality of DL reference signal (RS) transmissions from the network entity; and The plurality of DL RS transmissions are forwarded to the UE using the DL control voltage, and wherein the at least one UE UL beam is determined based on a measurement set associated with the plurality of DL RS transmissions.

28. The apparatus of claim 27, wherein the measurement set associated with the plurality of DL RS transmissions comprises a reference signal received power (RSRP) or a signal to interference plus noise ratio (SINR) of the DL RS transmissions.

29. The apparatus of claim 26, wherein the RIS UL beam indicated by the network entity is a beam having a best beam measurement or a most suitable beam measurement from the set of RIS UL beams.

30. The apparatus of claim 26, further comprising at least one of a transceiver or an antenna coupled to the at least one processor.

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