Doppler frequency estimation for reconfigurable smart surface communication links

Abstract

Various aspects of the present disclosure generally relate to wireless communications. In some aspects, a user equipment (UE) may receive, from a network node, indications of time domain twiddle factors associated with respective ones of one or more reconfigurable smart surfaces (RISs). The UE may receive respective reference signals during the time domain measurement occasion via a direct link with the network node and via one or more indirect links associated with the one or more RISs. The UE may send a report to the network node indicating estimated Doppler frequencies for respective links, including the direct link and one or more indirect links, in association with measurements of respective reference signals, the estimated Doppler frequencies being estimated using time domain twiddle factors associated with the respective RISs. Numerous other aspects are described.

Description

Technical Field

[0001] All aspects of this disclosure relate to wireless communication in general, and to techniques and apparatus for Doppler frequency estimation for reconfigurable smart surface (RIS) communication links. Background Technology

[0002] Wireless communication systems are widely deployed to provide a variety of telecommunications services, such as telephone, video, data, messaging, and broadcasting. Typical wireless communication systems employ multiple access technologies that enable communication with multiple users by sharing available system resources (e.g., bandwidth, transmit power, etc.). 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, Time Division Synchronous Code Division Multiple Access (TD-SCDMA) systems, and Long Term Evolution (LTE). LTE / LTE-Advanced is a set of enhancements to the Universal Mobile Telecommunications System (UMTS) mobile standard issued by the 3rd Generation Partnership Project (3GPP).

[0003] A wireless network may include one or more network nodes that support communication for wireless communication devices, such as user equipment (UE) or multiple UEs. A UE may communicate with network nodes via downlink and uplink communication. A “downlink” (or “DL”) refers to the communication link from the network node to the UE, and an “uplink” (or “UL”) refers to the communication link from the UE to the network node. Some wireless networks may support device-to-device communication, such as via local links (e.g., sidelinks (SL), wireless local area network (WLAN) links, and / or wireless personal area network (WPAN) links, among other examples).

[0004] The aforementioned multiple access technologies have been adopted in various telecommunications standards to provide a common protocol that enables different UEs to communicate at the city, country, region, and / or global levels. New Radio (NR) (which may be referred to as 5G) is a set of enhancements to the LTE mobile standard issued by 3GPP. NR is designed to better support mobile broadband internet access by: improving spectrum efficiency; reducing costs; improving service; utilizing new spectrum; and better integrating with other open standards by using Orthogonal Frequency Division Multiplexing (OFDM) with Cyclic Prefix (CP) on the downlink (CP-OFDM), and CP-OFDM and / or Single Carrier Frequency Division Multiplexing (SC-FDM) (also known as Discrete Fourier Transform Extended OFDM (DFT-s-OFDM)) on the uplink; and supporting beamforming, Multiple-Input Multiple-Output (MIMO) antenna technologies and carrier aggregation. Further improvements to LTE, NR, and other radio access technologies remain useful as the demand for mobile broadband access continues to increase. Summary of the Invention

[0005] Some aspects described herein relate to a user equipment (UE) for wireless communication. The UE may include memory and one or more processors coupled to the memory. One or more processors may be configured to receive from a network node an indication of a time-domain rotation factor associated with a corresponding RIS in one or more reconfigurable smart surfaces (RIS). One or more processors may be configured to receive a corresponding reference signal during a time-domain measurement event via a direct link to the network node and via one or more indirect links associated with the one or more RIS. One or more processors may be configured to send a report to the network node, in association with the measurement of these corresponding reference signals, indicating estimated Doppler frequencies of the corresponding links, including the direct links and one or more indirect links, which are estimated using these time-domain rotation factors associated with the corresponding RIS.

[0006] Some aspects described herein relate to a network node for wireless communication. The network node may include memory and one or more processors coupled to that memory. One or more processors may be configured to transmit, to a UE and one or more RIS, an indication of a time-domain rotation factor associated with a respective RIS among the one or more RIS. One or more processors may be configured to transmit a reference signal during a time-domain measurement event via a direct link to the UE and via one or more indirect links associated with the one or more RIS. One or more processors may be configured to receive a report associated with the UE, indicating, in connection with the measurement of the reference signal, estimated Doppler frequencies of the respective links, including the direct link and one or more indirect links, which are estimated using these time-domain rotation factors associated with the respective RIS.

[0007] Some aspects described herein relate to a method for wireless communication performed by a UE. The method may include receiving from a network node an indication of a time-domain rotation factor associated with a respective RIS in one or more RISs. The method may include receiving a respective reference signal during a time-domain measurement period via a direct link to the network node and via one or more indirect links associated with the one or more RISs. The method may include sending a report to the network node, in association with measurements of these respective reference signals, indicating estimated Doppler frequencies of the respective links, including the direct link and one or more indirect links, which are estimated using these time-domain rotation factors associated with the respective RISs.

[0008] Some aspects described herein relate to a method for wireless communication performed by a network node. The method may include transmitting, to a UE and one or more RIS, an indication of a time-domain rotation factor associated with a respective RIS among the one or more RIS. The method may include transmitting a reference signal during a time-domain measurement period via a direct link to the UE and via one or more indirect links associated with the one or more RIS. The method may include receiving a report associated with the UE, which, in connection with a measurement of the reference signal, indicates estimated Doppler frequencies of the respective links, including the direct link and one or more indirect links, which are estimated using these time-domain rotation factors associated with the respective RIS.

[0009] Some aspects described herein relate to a Reference Array (RIS) for wireless communication. The RIS may include memory and one or more processors coupled to the memory. The one or more processors may be configured to receive from a network node an indication of a time-domain rotation factor associated with the RIS. The one or more processors may be configured to reflect a reference signal associated with the network node using reflection coefficients based on the time-domain rotation factor.

[0010] Some aspects described herein relate to a method for wireless communication performed by a RIS (Reference Signal Array). The method may include receiving an indication from a network node of a time-domain rotation factor associated with the RIS. The method may also include using reflection coefficients based on the time-domain rotation factor to reflect a reference signal associated with the network node.

[0011] Some aspects described herein relate to a non-transitory computer-readable medium storing a set of instructions for wireless communication by a UE. When executed by one or more processors of the UE, the set of instructions enables the UE to: receive from a network node an indication of a time-domain rotation factor associated with a respective RIS in one or more RISs. When executed by one or more processors of the UE, the set of instructions enables the UE to: receive a corresponding reference signal during a time-domain measurement opportunity via a direct link to the network node and via one or more indirect links associated with the one or more RISs. When executed by one or more processors of the UE, the set of instructions enables the UE to: send a report to the network node indicating, in association with the measurement of these corresponding reference signals, estimated Doppler frequencies of the corresponding links, including the direct link and one or more indirect links, which are estimated using these time-domain rotation factors associated with these corresponding RISs.

[0012] Some aspects described herein relate to a non-transitory computer-readable medium storing a set of instructions for wireless communication by a network node. When executed by one or more processors of the network node, the set of instructions enables the network node to: send indications to a UE and one or more RIS (Reference Components) of time-domain rotation factors associated with a respective RIS. When executed by one or more processors of the network node, the set of instructions enables the network node to: transmit a reference signal during a time-domain measurement event via a direct link to the UE and via one or more indirect links associated with the one or more RIS. When executed by one or more processors of the network node, the set of instructions enables the network node to: receive a report associated with the UE indicating, in connection with the measurement of the reference signal, estimated Doppler frequencies of the respective links, including the direct link and one or more indirect links, which are estimated using these time-domain rotation factors associated with these respective RIS.

[0013] Some aspects described herein relate to a non-transitory computer-readable medium storing an instruction set for wireless communication by a RIS. When executed by one or more processors of the RIS, the instruction set enables the RIS to: receive from a network node an indication of a time-domain rotation factor associated with the RIS. When executed by one or more processors of the RIS, the instruction set enables the RIS to: reflect a reference signal associated with the network node using reflection coefficients based on the time-domain rotation factor.

[0014] Some aspects described herein relate to an apparatus for wireless communication. The apparatus may include components for receiving from a network node an indication of a time-domain rotation factor associated with a respective RIS in one or more RIS. The apparatus may include components for receiving a respective reference signal during a time-domain measurement, via a direct link to the network node and via one or more indirect links associated with the one or more RIS. The apparatus may include components for sending a report to the network node, the report indicating, in association with the measurement of these respective reference signals, estimated Doppler frequencies of the respective links, including the direct link and one or more indirect links, which are estimated using these time-domain rotation factors associated with the respective RIS.

[0015] Some aspects described herein relate to an apparatus for wireless communication. The apparatus may include components for transmitting, to a UE and one or more RIS, an indication of a time-domain rotation factor associated with a respective RIS among the one or more RIS. The apparatus may include components for transmitting a reference signal during a time-domain measurement event via a direct link to the UE and via one or more indirect links associated with the one or more RIS. The apparatus may include components for receiving a report associated with the UE, which, in connection with the measurement of the reference signal, indicates estimated Doppler frequencies of the respective links, including the direct link and one or more indirect links, which are estimated using the time-domain rotation factors associated with these respective RIS.

[0016] Some aspects described herein relate to an apparatus for wireless communication. The apparatus may include components for receiving from a network node an indication of a time-domain rotation factor associated with the apparatus. The apparatus may include components for reflecting a reference signal associated with the network node using a reflection coefficient based on the time-domain rotation factor.

[0017] The entirety of the terms includes methods, apparatus, systems, computer program products, non-transitory computer-readable media, user equipment, base stations, network entities, network nodes, wireless communication devices and / or processing systems as fully described herein with reference to the accompanying drawings and description and illustrated as illustrated in the drawings and description.

[0018] The features and technical advantages of the examples according to this disclosure have been summarized rather extensively above in order to provide a better understanding of the detailed description that follows. Additional features and advantages will be described below. The disclosed concepts and specific examples can be readily used as the basis for modifying or designing other structures for achieving the same purpose of this disclosure. Such equivalent constructions do not depart from the scope of the appended claims. The characteristics of the concepts disclosed herein, in both their organization and manner of operation, and the associated advantages, will be better understood by considering the following description in conjunction with the accompanying drawings. Each of the drawings provided is for illustrative and descriptive purposes and not as a definition of limitation of the claims.

[0019] While aspects are described herein by way of example, those skilled in the art will understand that such aspects can be implemented in many different arrangements and scenarios. The techniques described herein can be implemented using different platform types, devices, systems, shapes, sizes, and / or package arrangements. For example, some aspects can be implemented via integrated chip implementations or other devices based on non-modular components (e.g., end-user equipment, vehicles, communication equipment, computing devices, industrial equipment, retail / shopping devices, medical devices, and / or artificial intelligence devices). Aspects can be implemented in chip-level components, modular components, non-modular components, non-chip-level components, device-level components, and / or system-level components. Devices incorporating the described aspects and features may include additional components and features for implementing and practicing the claimed and described aspects. For example, the transmission and reception of wireless signals may include one or more components for analog and digital purposes (e.g., hardware components including antennas, radio frequency (RF) chains, power amplifiers, modulators, buffers, processors, interleavers, adders, and / or summers). The aspects described herein are intended to be practiced in a wide variety of devices, components, systems, distributed arrangements, and / or end-user equipment of various sizes, shapes, and configurations. Attached Figure Description

[0020] To gain a full understanding of the foregoing features of this disclosure, a more specific description of the brief overview can be obtained by referring to various aspects, some of which are illustrated in the accompanying drawings. However, it should be noted that the drawings illustrate only certain typical aspects of this disclosure and are therefore not to be considered as limiting its scope, as other equally valid aspects may be acknowledged in this description. The same reference numerals in different drawings may identify the same or similar elements.

[0021] Figure 1 This is a diagram illustrating an example of a wireless network according to the present disclosure.

[0022] Figure 2 This is a diagram illustrating an example of communication between a network node and a user equipment (UE) in a wireless network according to the present disclosure.

[0023] Figure 3 This is a diagram illustrating an example decomposed base station architecture according to this disclosure.

[0024] Figure 4 This is a diagram illustrating an example of communication using a device with forwarding capabilities according to this disclosure.

[0025] Figure 5 This is a diagram illustrating an example of a communication link in a wireless network including a reconfigurable smart surface (RIS) according to the present disclosure.

[0026] Figure 6This is a diagram illustrating an example of Doppler frequency estimation for a RIS communication link, based on this disclosure.

[0027] Figure 7 This is a diagram illustrating an example of Doppler frequency estimation for a RIS communication link, based on this disclosure.

[0028] Figure 8 This is a diagram illustrating an example procedure performed by a UE according to this disclosure, for example.

[0029] Figure 9 This is a diagram illustrating an example process performed, for example, by a network node according to this disclosure.

[0030] Figure 10 This is a diagram illustrating an example process performed, for example, by a RIS, according to this disclosure.

[0031] Figure 11 This is a diagram of an example device for wireless communication according to the present disclosure.

[0032] Figure 12 This is a diagram of an example device for wireless communication according to the present disclosure.

[0033] Figure 13 This is a diagram of an example device for wireless communication according to the present disclosure. Detailed Implementation

[0034] A transmitting device can send signals reflected by a beam reflector to a receiving device. The beam reflector can be a reconfigurable smart surface (RIS) with an array of passive and reconfigurable reflective elements, which can improve coverage and spectral efficiency at low deployment cost. The reconfigurability of the RIS allows transmitting devices such as network nodes (or user equipment (UE)) to implement multiple anomalous reflections, which are reflections with altered reflection angles (e.g., violating Snell's law). Each reflection can be specified by the target incident direction and the reflection direction. The ability to select multiple anomalous reflections gives network nodes more options or greater flexibility in UE selection and enhances the end-to-end channel to the UE.

[0035] In some cases, the UE can measure and / or estimate the Doppler frequencies of the direct and / or indirect links associated with the UE. The Doppler effect is the phenomenon where the frequency of a wave changes as the source and observer of a wave move relative to each other. In the context of wireless communication, the source is the transmitting antenna, and the observer is the receiving antenna. The Doppler effect can cause a drift in the frequency of the received signal relative to the frequency of the transmitted signal, which can affect the accuracy of signal detection and decoding. In high-speed scenarios, the relative motion between the transmitter and receiver can cause Doppler drift in the frequency of the transmitted signal. This drift can cause the received signal to fall outside the expected frequency band, leading to errors in signal detection and decoding. Estimating the Doppler frequency allows network nodes and / or the UE to mitigate the effects of Doppler drift. By knowing the Doppler frequency, network nodes and / or the UE can adjust the transmitting frequency to compensate for Doppler drift and keep the received signal within the expected frequency band. This allows for more reliable and accurate signal detection and decoding, which improves the performance of the wireless communication system.

[0036] In some cases, the UE can measure each link associated with it individually to facilitate Doppler frequency estimation. For example, the UE can use a first time-domain timing to measure the direct link between the UE and the network node to facilitate Doppler frequency estimation for the direct link. In other time-domain timings, the UE can measure the corresponding indirect link between the UE and the network node to facilitate Doppler frequency estimation for the indirect link. The UE can perform measurement and / or Doppler frequency estimation at different time-domain timings, allowing the UE to reliably identify and measure each link. The network node can receive reports of measurement and / or Doppler frequency estimation. In some examples, the network node can estimate or determine the Doppler frequency of each link based on or in response to reports of measurement and / or Doppler frequency estimation. The network node can configure (e.g., associated with indirect links) each device with forwarding capabilities based on the estimated Doppler frequencies. For example, the network node can configure each device with forwarding capabilities (e.g., each RIS) such that zero or only one Doppler frequency exists in the signal received by the UE. This allows the UE to mitigate Doppler frequencies in the received signal (for example, if there are multiple Doppler frequencies in the received signal, the UE may not be able to mitigate all of them, resulting in a degradation in signal detection and decoding).

[0037] However, measuring different links at appropriate time-domain times (e.g., to mitigate interference and / or measurement confusion between different links) can consume radio resources (e.g., time-domain, frequency-domain, and / or spatial-domain resources) and / or introduce delays associated with performing measurements on different links. For example, the total radio resource consumption and / or processing delay can be significant when using different radio resources to measure each link (e.g., for Doppler frequency estimation) (e.g., when the UE and network nodes are communicating using a large number of indirect links and / or devices with forwarding capabilities). If fewer radio resources and / or time-domain times are used to measure each link (e.g., for Doppler frequency estimation), fewer time-domain resources can be used to measure each link, resulting in less accurate and / or less reliable measurements. Therefore, the performance of Doppler frequency estimation (e.g., measurement-based) can be degraded.

[0038] Various aspects are involved in Doppler frequency estimation as a whole. Some aspects are more specifically involved in Doppler frequency estimation for RIS communication links. In some aspects, the UE may use shared or public radio resources to perform simultaneous Doppler frequency measurements on direct links and (e.g., associated with RIS reflections) one or more indirect links. For example, the UE may receive an indication of a time-domain rotation factor associated with a corresponding RIS in one or more RISs. The UE may receive a corresponding reference signal via a direct link to a network node and via one or more indirect links associated with one or more RISs during a time-domain measurement. The UE may send a report associated with the measurement of the corresponding reference signal, indicating the estimated Doppler frequencies of the corresponding links, including the direct link and one or more indirect links, wherein these estimated Doppler frequencies are estimated using the time-domain rotation factor associated with the corresponding RIS.

[0039] Specific aspects of the subject matter described in this disclosure can be implemented to achieve one or more of the following potential advantages. In some examples, by using a time-domain rotation factor associated with Doppler frequency estimation for indirect links, the described techniques can be used to reduce the amount of radio resources consumed and / or delay associated with estimating (e.g., associated with RIS) the Doppler frequencies of indirect links. For example, it can enable the UE to identify the Doppler spectrum of a corresponding indirect link based on the time-domain rotation factor, thereby enabling the UE to perform measurements of the corresponding indirect link using shared radio resources (e.g., the Doppler spectrum of the indirect link can be separated due to the use of the time-domain rotation factor, thereby reducing the possibility of inter-link interference and / or confusion at the UE regarding which measurement corresponds to which link). Furthermore, because the links use shared radio resources, the received signal-to-noise ratio (SNR) of each link can be improved.

[0040] For example, one or more indirect links are associated with reflection coefficients applied by a corresponding RIS (Reflection Component) associated with a time-domain rotation factor. At a given time-domain timing, each RIS can reflect a signal using a reflection coefficient based on the time-domain rotation factor associated with that RIS. This makes it possible to separate the Doppler spectrum of the received signal at the UE. Therefore, the UE can estimate the Doppler frequency of each link using the corresponding Doppler spectrum (e.g., identified based on a signaling notification or configured time-domain rotation factor). For example, for an indirect link associated with a given RIS, the Doppler spectrum associated with that RIS can be a drifted version of the channel Doppler spectrum associated with the channel response, where the drift associated with the Doppler spectrum is based on the time-domain rotation factor associated with the RIS. This allows the UE to accurately identify the Doppler spectrum of each indirect link and / or each RIS, thereby improving the performance and / or efficiency of Doppler frequency estimation.

[0041] Various aspects of this disclosure are described more fully below with reference to the accompanying drawings. However, this disclosure may be embodied in many different forms and should not be construed as limited to any particular structure or function presented throughout this disclosure. Rather, these aspects are provided so that this disclosure will be comprehensive and complete, and will fully convey the scope of this disclosure to those skilled in the art. Those skilled in the art will appreciate that the scope of this disclosure is intended to cover any aspect of this disclosure disclosed herein, whether implemented independently of or in combination with any other aspect of this disclosure. For example, any number of aspects set forth herein may be used to implement an apparatus or practice. Furthermore, the scope of this disclosure is intended to cover such apparatus or methods practiced using structures, functions, or structures and functions other than those set forth herein or different from the various aspects of the disclosure set forth herein. It should be understood that any aspect of this disclosure disclosed herein may be embodied by one or more elements of the present claims.

[0042] Various devices and techniques will now be used to illustrate several aspects of a telecommunications system. These devices and techniques will be described in detail below and illustrated in the accompanying drawings by various boxes, modules, components, circuits, steps, processes, or algorithms (collectively, “elements”). These elements can be implemented using hardware, software, or a combination thereof. Whether such elements are implemented as hardware or software depends on the specific application and the design constraints imposed on the system as a whole.

[0043] Although terms generally associated with 5G or New Radio (NR) Radio Access Technology (RAT) may be used herein to describe aspects, aspects of this disclosure may be applied to other RATs, such as 3G RAT, 4G RAT and / or 5G and later (e.g., 6G) RATs.

[0044] Figure 1 This is a diagram illustrating an example of a wireless network 100 according to the present disclosure. The wireless network 100 may be a 5G (e.g., NR) network and / or a 4G (e.g., Long Term Evolution (LTE)) network, or may include elements of a 5G (e.g., NR) network and / or elements of a 4G (e.g., LTE) network, among other examples. The wireless network 100 may include one or more network nodes 110 (shown as network node 110a, network node 110b, network node 110c, and network node 110d), one or more UEs 120 (shown as UE 120a, UE 120b, UE 120c, and UE 120d), and / or other entities. Network node 110 is a network node that communicates with UE 120. As shown, network node 110 may include one or more network nodes. For example, network node 110 can be an aggregated network node, meaning that the aggregated network node is configured to utilize a radio protocol stack that is physically or logically integrated within a single radio access network (RAN) node (e.g., within a single device or unit). As another example, network node 110 can be a decomposed network node (sometimes referred to as a decomposed base station), meaning that network node 110 is configured to utilize a protocol stack that is physically or logically distributed among two or more nodes (such as one or more central units (CUs), one or more distributed units (DUs), or one or more radio units (RUs)).

[0045] In some examples, network node 110 is or includes network nodes (such as RUs) that communicate with UE 120 via a radio access link. In some examples, network node 110 is or includes network nodes (such as DUs) that communicate with other network nodes 110 via a fronthaul or midhaul link. In some examples, network node 110 is or includes network nodes (such as CUs) that communicate with other network nodes 110 via a midhaul link or with the core network via a backhaul link. In some examples, network node 110 (such as aggregated network node 110 or decomposed network node 110) may include multiple network nodes, such as one or more RUs, one or more CUs, and / or one or more DUs. Network node 110 may include, for example, NR base stations, LTE base stations, Node Bs, eNBs (e.g., in 4G), gNBs (e.g., in 5G), access points, Transmit / Receive Points (TRPs), DUs, RUs, CUs, network mobility elements, core network nodes, network elements, network equipment, RAN nodes, or combinations thereof. In some examples, network nodes 110 can interconnect with each other or with one or more other network nodes 110 in the wireless network 100 using any suitable transport network through various types of fronthaul interfaces, midhaul interfaces, and / or backhaul interfaces (such as direct physical connections, air interfaces, or virtual networks).

[0046] In some examples, network node 110 may provide communication coverage for a specific geographic area. In the 3rd Generation Partnership Project (3GPP), depending on the context in which the term is used, the term "cell" may refer to the coverage area of ​​network node 110 and / or the network node subsystem serving that coverage area. Network node 110 may provide communication coverage for macrocells, picocells, femtocells, and / or another type of cell. A macrocell may cover a relatively large geographic area (e.g., a radius of several kilometers) and may allow unrestricted access by UE 120 with a service subscription. A picocell may cover a relatively small geographic area and may allow unrestricted access by UE 120 with a service subscription. A femtocell may cover a relatively small geographic area (e.g., a home) and may allow restricted access by UE 120 associated with the femtocell (e.g., UE 120 in a Closed Subscriber Group (CSG)). Network node 110 used for macrocells may be referred to as a macro network node. Network node 110 used for picocells may be referred to as a pico network node. The network node 110 used for femtocells can be referred to as a femtocell network node or a home network node. Figure 1In the example shown, network node 110a can be a macro network node for macro cell 102a, network node 110b can be a pico network node for pico cell 102b, and network node 110c can be a femto network node for femto cell 102c. Network nodes can support one or more (e.g., three) cells. In some examples, the cells may not necessarily be stationary, and the geographical area of ​​the cells may move depending on the location of the mobile network node 110 (e.g., a mobile network node).

[0047] In some aspects, the term "base station" or "network node" may refer to an aggregated base station, a decomposed base station, an integrated access and backhaul (IAB) node, a relay node, or one or more components thereof. For example, in some aspects, "base station" or "network node" may refer to a CU, DU, RU, a near real-time (near RT) RAN intelligent controller (RIC), or a non-real-time (non-RT) RIC, or a combination thereof. In some aspects, the term "base station" or "network node" may refer to a device configured to perform one or more functions (such as those described herein in conjunction with network node 110). In some aspects, the term "base station" or "network node" may refer to multiple devices configured to perform one or more functions. For example, in some distributed systems, each of multiple different devices (which may be located in the same geographical location or different geographical locations) may be configured to perform at least a portion of a function, or to repeatedly perform at least a portion of that function, and the term "base station" or "network node" may refer to any one or more of these different devices. In some aspects, the term "base station" or "network node" may refer to one or more virtual base stations or one or more virtual base station functions. For example, in some aspects, two or more base station functions can be instantiated on a single device. In some aspects, the term "base station" or "network node" may refer to one base station function rather than another. In this way, a single device may include more than one base station.

[0048] Wireless network 100 may include one or more relay stations. A relay station is a network node that can receive data transmissions from upstream nodes (e.g., network node 110 or UE 120) and transmit data to downstream nodes (e.g., UE 120 or network node 110). A relay station may be a UE 120 that can relay transmissions for other UE 120s. Figure 1 In the example shown, network node 110d (e.g., a relay network node) can communicate with network node 110a (e.g., a macro network node) and UE 120d to facilitate communication between network node 110a and UE 120d. The network node 110 for relay communication may be referred to as a relay station, relay base station, relay network node, relay node, repeater, etc.

[0049] Wireless network 100 can be a heterogeneous network, comprising different types of network nodes 110, such as macro network nodes, pico network nodes, femto network nodes, relay network nodes, etc. These different types of network nodes 110 may have different transmit power levels, different coverage areas, and / or different effects on interference in wireless network 100. For example, macro network nodes may have high transmit power levels (e.g., 5 watts to 40 watts), while pico network nodes, femto network nodes, and relay network nodes may have lower transmit power levels (e.g., 0.1 watts to 2 watts).

[0050] Network controller 130 may be coupled to or communicate with a group of network nodes 110, and may provide coordination and control for these network nodes 110. Network controller 130 may communicate with network nodes 110 via a backhaul or midhaul link. Network nodes 110 may also communicate directly with each other, or indirectly via a wireless or wired backhaul link. In some aspects, network controller 130 may be a CU or a core network device, or may include a CU or a core network device.

[0051] UE 120 may be distributed throughout the wireless network 100, and each UE 120 may be stationary or mobile. UE 120 may include, for example, access terminals, terminals, mobile stations, and / or subscriber units. UE 120 may be a cellular phone (e.g., a smartphone), a personal digital assistant (PDA), a wireless modem, a wireless communication device, a handheld device, a laptop computer, a cordless phone, a wireless local loop (WLL) station, a tablet computer, a camera, a gaming device, a netbook, a smartbook, an ultrabook, a medical device, a biometric device, a wearable device (e.g., a smartwatch, smart clothing, smart glasses, a smart wristband, smart jewelry (e.g., a smart ring or smart bracelet)), an entertainment device (e.g., a music device, a video device, and / or a satellite radio), a vehicle component or sensor, a smart meter / sensor, industrial manufacturing equipment, a GPS device, a UE function of a network node, and / or any other suitable device configured to communicate via wireless or wired media.

[0052] Some UEs 120 may be considered machine-type communication (MTC) or evolved or enhanced machine-type communication (eMTC) UEs. MTC UEs and / or eMTC UEs may include, for example, robots, drones, remote devices, sensors, meters, monitors, and / or location tags that can communicate with network nodes, another device (e.g., a remote device), or some other entity. Some UEs 120 may be considered Internet of Things (IoT) devices and / or may be implemented as NB-IoT (Narrowband IoT) devices. Some UEs 120 may be considered customer premises equipment. UEs 120 may be included within a housing that houses the components of the UE 120, such as processor components and / or memory components. In some examples, the processor components and memory components may be coupled together. For example, the processor components (e.g., one or more processors) and memory components (e.g., memory) may be operatively coupled, communicatively coupled, electronically coupled, and / or electrically coupled.

[0053] Generally, any number of wireless networks 100 can be deployed in a given geographical area. Each wireless network 100 can support a specific RAT and can operate on one or more frequencies. A RAT may be referred to as a radio technology, air interface, etc. A frequency may be referred to as a carrier, frequency channel, etc. Each frequency in a given geographical area can support a single RAT to avoid interference between wireless networks using different RATs. In some cases, NR or 5G RAT networks can be deployed.

[0054] In some examples, two or more UEs 120 may communicate directly using one or more sidelink channels (e.g., without using network node 110 as an intermediary for communication with each other). For example, UEs 120 may communicate using peer-to-peer (P2P) communication, device-to-device (D2D) communication, vehicle-to-everything (V2X) protocols (e.g., which may include vehicle-to-vehicle (V2V), vehicle-to-infrastructure (V2I), or vehicle-to-pedestrian (V2P) protocols) and / or mesh networks. In such examples, UEs 120 may perform scheduling operations, resource selection operations, and / or other operations described elsewhere herein as being performed by network node 110.

[0055] Devices in Wireless Network 100 can communicate using the electromagnetic spectrum, which can be subdivided into various categories, bands, channels, etc., based on frequency or wavelength. For example, devices in Wireless Network 100 can communicate using one or more operating frequency bands. In 5G NR, two initial operating frequency bands have been designated as frequency ranges FR1 (410MHz to 7.125GHz) and FR2 (24.25GHz to 52.6GHz). It should be understood that although a portion of FR1 is greater than 6GHz, FR1 is generally (interchangeably) referred to as the “sub-6GHz” band in various documents and articles. Similar naming issues sometimes occur with FR2, which is generally (interchangeably) referred to as the “millimeter wave” band in documents and articles, although this is different from the Extremely High Frequency (EHF) band (30GHz to 300GHz) designated as a “millimeter wave” band by the International Telecommunication Union (ITU).

[0056] The frequencies between FR1 and FR2 are generally referred to as mid-band frequencies. Recent 5G NR studies have identified the operating bands used for these mid-band frequencies as the frequency range designation FR3 (7.125 GHz to 24.25 GHz). Bands falling within FR3 can inherit FR1 and / or FR2 characteristics, and thus can effectively extend the features of FR1 and / or FR2 to mid-band frequencies. Furthermore, higher frequency bands are currently being explored to extend 5G NR operation beyond 52.6 GHz. For example, three higher operating frequency bands have been identified as the frequency range designations FR4a or FR4-1 (52.6 GHz to 71 GHz), FR4 (52.6 GHz to 114.25 GHz), and FR5 (114.25 GHz to 300 GHz). Each of these higher frequency bands falls within the EHF band.

[0057] Considering the examples above, unless otherwise specifically stated, it should be understood that when the term "below 6 GHz" is used herein, it can broadly refer to frequencies below 6 GHz, within FR1, or including intermediate frequency band frequencies. Furthermore, unless otherwise specifically stated, it should be understood that when the term "millimeter wave" is used herein, it can broadly refer to frequencies that can include intermediate frequency band frequencies, within FR2, FR4, FR4-a, or FR4-1 and / or FR5, or within the EHF band. Modifications to frequencies included in these operating frequency bands (e.g., FR1, FR2, FR3, FR4, FR4-a, FR4-1, and / or FR5) are contemplated, and the techniques described herein are applicable to those modified frequency ranges.

[0058] like Figure 1As shown, the wireless network 100 may include a device 160 with forwarding capabilities. A first device (e.g., UE 120a, network node 110) may communicate with a second device (e.g., network node 110, UE 120a) directly or by reflecting signals via the device 160 with forwarding capabilities (e.g., RIS or another device). The first device may be a transmitting device (e.g., network node 110 or UE 120), and the second device may be a receiving device (e.g., UE 120 or network node 110) because the transmitting device is sending signals to the receiving device.

[0059] In some aspects, UE 120 may include a communication manager 140. As described in more detail elsewhere herein, the communication manager 140 may receive from a network node an indication of a time-domain rotation factor associated with a corresponding RIS in one or more RIS; receive a corresponding reference signal during a time-domain measurement opportunity via a direct link to the network node and via one or more indirect links associated with the one or more RIS; and send a report to the network node indicating, in association with the measurement of the corresponding reference signal, estimated Doppler frequencies of the corresponding links, including the direct links and one or more indirect links, which are estimated using the time-domain rotation factor associated with the corresponding RIS. Additionally or alternatively, the communication manager 140 may perform one or more other operations described herein.

[0060] In some aspects, network node 110 may include communication manager 150. As described in more detail elsewhere herein, communication manager 150 may send indications to the UE and one or more RIS of a time-domain rotation factor associated with a respective RIS; transmit reference signals during time-domain measurement times via a direct link to the UE and via one or more indirect links associated with the one or more RIS; and receive reports associated with the UE indicating, in connection with the measurement of the reference signals, estimated Doppler frequencies of the respective links, including the direct links and one or more indirect links, which are estimated using the time-domain rotation factor associated with the respective RIS. Additionally or alternatively, communication manager 150 may perform one or more other operations described herein.

[0061] In some aspects, the forwarding-capable device 160 may include a communication manager 170. As described in more detail elsewhere herein, the communication manager 170 may receive from a network node an indication of a time-domain rotation factor associated with the forwarding-capable device 160; and may use reflection coefficients based on the time-domain rotation factor to reflect a reference signal associated with the network node. Additionally or alternatively, the communication manager 170 may perform one or more other operations described herein.

[0062] As indicated above, Figure 1 This is provided as an example. Other examples are available with reference to [the relevant information]. Figure 1 The examples described are different.

[0063] Figure 2 This is a diagram illustrating example 200 of communication between network node 110 and UE 120 in a wireless network 100 according to this disclosure. Network node 110 may be equipped with a set of antennas 234a to 234t, such as... T One antenna ( T ≥1). The UE 120 may be equipped with a set of antennas 252a to 252r, such as R One antenna ( R ≥1). Network node 110 of Example 200 includes one or more radio frequency components, such as antenna 234 and modem 232. In some examples, network node 110 may include an interface, communication components, or another component that facilitates communication with UE 120 or another network node. Some network node 110 may not include radio frequency components that facilitate direct communication with UE 120, such as one or more CUs or one or more DUs.

[0064] At network node 110, transmitting processor 220 may receive data from data source 212 intended for use by UE 120 (or a group of UEs 120). Transmitting processor 220 may select one or more modulation and decoding schemes (MCS) for UE 120 based at least in part on one or more Channel Quality Indicators (CQIs) received from UE 120. Network node 110 may process (e.g., encode and modulate) the data for UE 120 based at least in part on the MCS selected for UE 120 and may provide data symbols for UE 120. Transmitting processor 220 may process system information (e.g., for Semi-Static Resource Allocation Information (SRPI)) and control information (e.g., CQI requests, grants, and / or upper-layer signaling) and provide overhead symbols and control symbols. Transmitting processor 220 may generate reference symbols for reference signals (e.g., Cell-Specific Reference Signal (CRS) or Demodulation Reference Signal (DMRS)) and synchronization signals (e.g., Primary Synchronization Signal (PSS) or Secondary Synchronization Signal (SSS)). The transmit (TX) multiple-input multiple-output (MIMO) processor 230 can perform spatial processing (e.g., pre-decoding) on ​​data symbols, control symbols, overhead symbols, and / or reference symbols where applicable, and can transmit a set of output symbol streams (e.g., T Each output symbol stream is provided to a corresponding set of modems 232 (e.g., ...). TEach modem 232 (shown as modems 232a to 232t) may be used. For example, each output symbol stream may be provided to a modulator component (shown as MOD) of modem 232. Each modem 232 may use a corresponding modulator component to process the corresponding output symbol stream (e.g., for OFDM) to obtain an output sample stream. Each modem 232 may also use a corresponding modulator component to process (e.g., convert to analog, amplify, filter, and / or upconvert) the output sample stream to obtain a downlink signal. Modems 232a to 232t may be used via a corresponding set of antennas 234 (e.g., T Each antenna (shown as antennas 234a to 234t) is used to transmit a set of downlink signals (e.g., T (One downlink signal).

[0065] At UE 120, a set of antennas 252 (shown as antennas 252a to 252r) can receive downlink signals from network node 110 and / or other network nodes 110 and can transmit a set of received signals (e.g., R (one received signal) is provided to a group of modems 254 (e.g., R Each modem 254 (shown as modems 254a to 254r) may be used. For example, each received signal may be provided to a demodulator component (shown as DEMOD) of modem 254. Each modem 254 may use a corresponding demodulator component to condition the received signal (e.g., filter, amplify, down-convert, and / or digitize) to obtain an input sample. Each modem 254 may use a demodulator component to further process the input sample (e.g., for OFDM) to obtain a received symbol. MIMO detector 256 may obtain the received symbols from modem 254, perform MIMO detection on the received symbols where applicable, and provide the detected symbols. Receiver processor 258 may process (e.g., demodulate and decode) the detected symbols, provide data for decoding for UE 120 to data sink 260, and provide decoded control information and system information to controller / processor 280. The term "controller / processor" may refer to one or more controllers, one or more processors, or a combination thereof. The channel processor can determine the Reference Signal Received Power (RSRP) parameter, Received Signal Strength Indicator (RSSI) parameter, Reference Signal Received Quality (RSRQ) parameter, and / or CQI parameter, among others. In some examples, one or more components of the UE 120 may be included in the housing 284.

[0066] Network controller 130 may include communication unit 294, controller / processor 290, and memory 292. Network controller 130 may include one or more devices, for example, in a core network. Network controller 130 may communicate with network node 110 via communication unit 294.

[0067] One or more antennas (e.g., antennas 234a to 234t and / or antennas 252a to 252r) may include one or more antenna panels, one or more antenna groups, one or more sets of antenna elements and / or one or more antenna arrays, and other examples, or may be included within one or more antenna panels, one or more antenna groups, one or more sets of antenna elements and / or one or more antenna arrays, and other examples. Antenna panels, antenna groups, sets of antenna elements and / or antenna arrays may include one or more antenna elements (within a single housing or multiple housings), a set of coplanar antenna elements, a set of non-coplanar antenna elements and / or be coupled to one or more transmitting and / or receiving components (such as...). Figure 2 One or more antenna elements (one or more components in a )

[0068] On the uplink, at UE 120, the transmit processor 264 can receive and process data from data source 262 and control information from controller / processor 280 (e.g., for reporting including RSRP, RSSI, RSRQ, and / or CQI). The transmit processor 264 can generate reference symbols for one or more reference signals. The symbols from the transmit processor 264 can be pre-decoded by the TX MIMO processor 266 where applicable, further processed by the modem 254 (e.g., for DFT-s-OFDM or CP-OFDM), and transmitted to network node 110. In some examples, the modem 254 of UE 120 may include a modulator and demodulator. In some examples, UE 120 includes a transceiver. The transceiver may include any combination of antenna 252, modem 254, MIMO detector 256, receive processor 258, transmit processor 264, and / or TX MIMO processor 266. The transceiver may be used by a processor (e.g., controller / processor 280) and memory 282 to execute this document (e.g., reference). Figures 6 to 13 ( ) any aspect of the methods described in the method.

[0069] At network node 110, uplink signals from UE 120 and / or other UEs may be received by antenna 234, processed by modem 232 (e.g., demodulator component of modem 232 (shown as DEMOD)), detected by MIMO detector 236 where applicable, and further processed by receive processor 238 to obtain decoded data and control information transmitted by UE 120. Receive processor 238 may provide the decoded data to data sink 239 and the decoded control information to controller / processor 240. Network node 110 may include communication unit 244 and may communicate with network controller 130 via communication unit 244. Network node 110 may include scheduler 246 to schedule one or more UEs 120 for downlink and / or uplink communication. In some examples, modem 232 of network node 110 may include modulator and demodulator. In some examples, network node 110 includes transceiver. The transceiver may include any combination of antenna 234, modem 232, MIMO detector 236, receive processor 238, transmit processor 220, and / or TX MIMO processor 230. The transceiver may be used by a processor (e.g., controller / processor 240) and memory 242 to execute this document (e.g., reference). Figures 6 to 13 ( ) any aspect of the methods described in the method.

[0070] The controller / processor 240 of network node 110, the controller / processor 280 of UE 120 and / or Figure 2 Any other component may perform one or more techniques associated with Doppler frequency estimation for the RIS communication link, as described in more detail elsewhere herein. In some respects, the forwarding-capable device 160 and / or RIS described herein is a network node 110, included in, or comprising Figure 2 One or more components of the network node 110 shown.

[0071] For example, the controller / processor 240 of network node 110, the controller / processor 280 of UE 120, and / or Figure 2 Any other component that can be executed or booted, for example Figure 8 The process 800 Figure 9 The process 900 Figure 10The operation of process 1000 and / or other processes as described herein. Memory 242 and memory 282 may store data and program code for network node 110 and UE 120, respectively. In some examples, memory 242 and / or memory 282 may include a non-transitory computer-readable medium storing one or more instructions (e.g., code and / or program code) for wireless communication. For example, one or more instructions, when executed by one or more processors of network node 110 and / or UE 120 (e.g., directly executed, or executed after compilation, transformation, and / or interpretation), may cause the one or more processors, UE 120, and / or network node 110 to execute or guide, for example... Figure 8 The process 800 Figure 9 The process 900 Figure 10 The operation of process 1000 and / or other processes as described herein. In some examples, execution instructions may include run instructions, transform instructions, compile instructions and / or interpret instructions, among others.

[0072] In some aspects, UE 120 includes: components for receiving from a network node an indication of a time-domain rotation factor associated with a corresponding RIS in one or more RISs; components for receiving a corresponding reference signal during a time-domain measurement opportunity via a direct link to the network node and via one or more indirect links associated with one or more RISs; and / or components for sending a report to the network node, the report indicating, in association with a measurement of the corresponding reference signal, estimated Doppler frequencies of the corresponding link, including the direct link and one or more indirect links, which are estimated using the time-domain rotation factor associated with the corresponding RIS. Components for enabling UE 120 to perform the operations described herein may include, for example, one or more of a communication manager 140, an antenna 252, a modem 254, a MIMO detector 256, a receive processor 258, a transmit processor 264, a TX MIMO processor 266, a controller / processor 280, or a memory 282.

[0073] In some aspects, network node 110 includes: components for transmitting an indication of a time-domain rotation factor associated with a corresponding RIS among the one or more RIS to a UE and one or more RIS; components for transmitting a reference signal during a time-domain measurement opportunity via a direct link with the UE and via one or more indirect links associated with the one or more RIS; and / or components for receiving a report associated with the UE, the report indicating, in connection with the measurement of the reference signal, estimated Doppler frequencies of the corresponding links including the direct link and one or more indirect links, the estimated Doppler frequencies being estimated using the time-domain rotation factor associated with the corresponding RIS. Components for enabling network node 110 to perform the operations described herein may include, for example, one or more of a communication manager 150, a transmit processor 220, a TX MIMO processor 230, a modem 232, an antenna 234, a MIMO detector 236, a receive processor 238, a controller / processor 240, a memory 242, or a scheduler 246.

[0074] In some aspects, the forwarding-capable device 160 (e.g., RIS) includes: components for receiving from a network node an indication of a time-domain rotation factor associated with the RIS; and / or components for reflecting a reference signal associated with the network node using a reflection coefficient based on the time-domain rotation factor. In some aspects, components for enabling the forwarding-capable device 160 to perform the operations described herein may include, for example, a communication manager 170, a processor, a controller, and / or one or more reconfigurable elements (or super-components), and one or more of the other examples.

[0075] Although Figure 2 The boxes in the diagram are illustrated as different components, but the functions described above with respect to these boxes may be implemented in a single hardware, software, or combined component, or in various combinations of components. For example, the functions described with respect to transmit processor 264, receive processor 258, and / or TX MIMO processor 266 may be performed by or under the control of controller / processor 280.

[0076] As indicated above, Figure 2 This is provided as an example. Other examples are available with reference to [the relevant information]. Figure 2 The examples described are different.

[0077] Communication systems, such as 5G NR systems, can be deployed in various ways with a variety of components or parts. In a 5G NR system or network, network nodes, network entities, network mobility elements, RAN nodes, core network nodes, network elements, base stations, or network equipment can be implemented in either a converged or decomposed architecture. For example, a base station (such as a Node B (NB), evolved NB (eNB), NR base station, 5G NB, access point (AP), TRP, or cell, and other examples) or one or more units (or components) performing base station functionality can be implemented as a converged base station (also known as a standalone base station or monolithic base station) or a decomposed base station. A “network entity” or “network node” can refer to a decomposed base station or one or more units of a decomposed base station (such as one or more CUs, one or more DUs, one or more RUs, or combinations thereof).

[0078] Aggregated base stations (e.g., aggregated network nodes) can be configured to utilize a radio protocol stack that is physically or logically integrated within a single RAN node (e.g., within a single device or cell). Decomposed base stations (e.g., decomposed network nodes) can be configured to utilize a protocol stack that is physically or logically distributed across two or more cells (such as one or more CUs, one or more DUs, or one or more RUs). In some examples, the CU may be implemented within a network node, and one or more DUs may be co-located with the CU, or alternatively, may be geographically or virtually distributed across one or more other network nodes. DUs may be implemented to communicate with one or more RUs. Each of the CU, DU, and RU may also be implemented as a virtual cell, such as a Virtual Central Unit (VCU), a Virtual Distributed Unit (VDU), or a Virtual Radio Unit (VRU), among other examples.

[0079] Base station type operation or network design can take into account the aggregation characteristics of base station functionality. For example, decomposed base stations can be utilized in IAB networks, Open Radio Access Networks (O-RAN (such as network configurations initiated by the O-RAN Alliance)), or Virtualized Radio Access Networks (vRAN, also known as Cloud Radio Access Networks (C-RAN)) to facilitate the scaling of communication systems by separating base station functionality into one or more units that can be deployed independently. Decomposed base stations can include functionality implemented across two or more units at various physical locations, as well as functionality virtually implemented for at least one unit, which enables flexibility in network design. Each unit of a decomposed base station can be configured for wired or wireless communication with at least one other unit of the decomposed base station.

[0080] As used herein, "outputting" or "transmitting" communication from network node 110 to UE 120 can refer to direct transmission (e.g., from network node 110 to UE 120) or indirect transmission via one or more other network nodes or devices. For example, if network node 110 is a DU, indirect transmission to UE 120 may include the DU outputting or transmitting communication to an RU and the RU transmitting communication to UE 120, or may include causing the RU to transmit communication (e.g., triggering the transmission of a physical layer reference signal). Similarly, "transmitting" communication from UE 120 to network node 110 can refer to direct transmission (e.g., from UE 120 to network node 110) or indirect transmission via one or more other network nodes or devices. For example, if network node 110 is a DU, indirect transmission to network node 110 may include UE 120 transmitting communication to an RU and the RU transmitting communication to the DU. Similarly, network node 110 “receiving” communication may refer to directly receiving a transmission carrying communication (e.g., from UE 120 to network node 110) or receiving communication (or information derived from receiving communication) via one or more other network nodes or devices.

[0081] Figure 3 This is an illustration of an example disaggregated base station architecture 300 according to the present disclosure. The disaggregated base station architecture 300 may include a CU 310, which may communicate directly with the core network 320 via a backhaul link, or indirectly with the core network 320 via one or more disaggregated control units (such as near-RT RIC 325 via an E2 link, or a non-RT RIC 315 associated with a Service Management and Orchestration (SMO) framework 305, or both). The CU 310 may communicate with one or more DUs 330 via a corresponding midhaul link (such as via an F1 interface). Each DU 330 may communicate with one or more RUs 340 via a corresponding fronthaul link. Each RU 340 may communicate with one or more UEs 120 via a corresponding radio frequency (RF) access link. In some implementations, a UE 120 may be served simultaneously by multiple RUs 340.

[0082] Each unit in the cells (including CU 310, DU 330, RU 340), as well as the near-RT RIC 325, non-RT RIC 315, and SMO frame 305, may include or be coupled to one or more interfaces configured to receive or transmit signals, data, or information (collectively, signals) via wired or wireless transmission media. Each unit in the cell, or an associated processor or controller providing instructions to one or more communication interfaces of the corresponding unit, may be configured to communicate with one or more units in other cells via transmission media. In some examples, each unit in the cell may include a wired interface and a wireless interface configured to receive signals or transmit signals to one or more units in other cells via a wired transmission media, and the wireless interface may include a receiver, transmitter, or transceiver (such as an RF transceiver) configured to receive signals or transmit signals to one or more units in other cells via a wireless transmission media, or both.

[0083] In some aspects, the CU 310 can host one or more higher-level control functions. Such control functions may include Radio Resource Control (RRC) functions, Packet Data Convergence Protocol (PDCP) functions, or Service Data Adaptation Protocol (SDAP) functions, among others. Each control function may be implemented using an interface configured to signal to other control functions hosted by the CU 310. The CU 310 may be configured to handle user plane functionalities (e.g., Central Unit-User Plane (CU-UP) functionalities), control plane functionalities (e.g., Central Unit-Control Plane (CU-CP) functionalities), or combinations thereof. In some specific implementations, the CU 310 may be logically split into one or more CU-UP units and one or more CU-CP units. When implemented in an O-RAN configuration, the CU-UP units may communicate bidirectionally with the CU-CP units via an interface such as an E1 interface. The CU 310 may be implemented to communicate with the DU 330 for network control and signaling purposes, as needed.

[0084] Each DU 330 may correspond to a logical unit comprising one or more base station functions for controlling the operation of one or more RU 340s. In some aspects, the DU 330 may host one or more of the Radio Link Control (RLC) layer, the Medium Access Control (MAC) layer, and one or more high physical (PHY) layers, at least in part, according to functional splits (such as those defined by 3GPP). In some aspects, one or more high PHY layers may be implemented by one or more modules for forward error correction (FEC) encoding and decoding, scrambling, and modulation and demodulation, among other examples. In some aspects, the DU 330 may also host one or more low PHY layers, such as those implemented by one or more modules for Fast Fourier Transform (FFT), Inverse FFT (iFFT), Digital Beamforming, or Physical Random Access Channel (PRACH) extraction and filtering, among other examples. Each layer (which may also be referred to as a module) may be implemented using an interface configured to communicate signals with other layers (and modules) hosted by the DU 330 or with control functions hosted by the CU 310.

[0085] Each RU 340 can implement lower-layer functionality. In some deployments, an RU 340 controlled by a DU 330 can correspond to a logical node that hosts RF processing functions or low-PHY layer functions, such as performing FFT, performing iFFT, digital beamforming, or PRACH extraction and filtering, and other examples, based on function splits (e.g., function splits defined by 3GPP) (such as lower-layer function splits). In this architecture, each RU 340 can be operated to handle over-the-air (OTA) communications with one or more UEs 120. In some specific implementations, the real-time and non-real-time aspects of control plane and user plane communications with the RU 340 can be controlled by the corresponding DU 330. In some scenarios, this configuration allows each DU 330 and CU 310 to be implemented in a cloud-based RAN architecture, such as a vRAN architecture.

[0086] The SMO framework 305 can be configured to support RAN deployment and provisioning of both non-virtualized and virtualized network elements. For non-virtualized network elements, the SMO framework 305 can be configured to support the deployment of dedicated physical resources for RAN coverage requirements, which can be managed via operation and maintenance interfaces such as the O1 interface. For virtualized network elements, the SMO framework 305 can be configured to interact with cloud computing platforms such as the Open Cloud (O-Cloud) platform 390 to perform network element lifecycle management (such as instantiating virtualized network elements) via cloud computing platform interfaces such as the O2 interface. Such virtualized network elements may include, but are not limited to, CU 310, DU 330, RU 340, non-RT RIC 315, and near-RTTRIC 325. In some specific implementations, the SMO framework 305 may communicate with 4G RAN hardware aspects such as the Open eNB (O-eNB) 311 via the O1 interface. Additionally, in some implementations, the SMO framework 305 can communicate directly with each of one or more RUs 340 via a corresponding O1 interface. The SMO framework 305 may also include a non-RT RIC 315 configured to support the functionality of the SMO framework 305.

[0087] The non-RT RIC 315 can be configured to include logical functions enabling non-real-time control and optimization of RAN elements and resources, including artificial intelligence / machine learning (AI / ML) workflows for model training and updates, or policy-based guidance for applications / features in the near-RT RIC 325. The non-RT RIC 315 can be coupled to or communicate with the near-RT RIC 325, such as via an A1 interface. The near-RT RIC 325 can be configured to include logical functions enabling near real-time control and optimization of RAN elements and resources via data collection and actions through an interface such as an E2 interface, connecting one or more CU 310s, one or more DU 330s, or both, and O-eNBs to the near-RT RIC 325.

[0088] In some implementations, to generate AI / ML models to be deployed in the near-RT RIC 325, the non-RT RIC 315 may receive parameters or external enrichment information from an external server. This information can be utilized by the near-RT RIC 325 and can be received from non-network data sources or network functions at the SMO framework 305 or the non-RT RIC 315. In some examples, the non-RT RIC 315 or the near-RT RIC 325 may be configured to tune RAN behavior or performance. For example, the non-RT RIC 315 may monitor long-term trends and patterns in performance and employ AI / ML models to perform corrective actions via the SMO framework 305 (such as reconfiguration via the O1 interface) or via the creation of RAN management policies (such as A1 interface policies).

[0089] As indicated above, Figure 3 This is provided as an example. Other examples are available with reference to [the relevant information]. Figure 3 The examples described are different.

[0090] Figure 4 This is a diagram illustrating example 400 of communication using a device with forwarding capabilities according to this disclosure. For example... Figure 4 As shown, network node 110 can communicate with UE 120 in a wireless network (such as wireless network 100). Network node 110 and UE 120 can communicate with each other using a device 160 with forwarding capabilities. For example, the device 160 with forwarding capabilities can reflect, refract, or redirect signals to network node 110 and / or UE 120. The device 160 with forwarding capabilities may also be referred to as a smart reflective surface or a software-controlled metasurface. In some examples, the device 160 with forwarding capabilities can be a RIS, a repeater, a relay, an amplification and forwarding device, a decoding and forwarding device, or another device capable of forwarding, reflecting, and / or refracting wireless communication signals.

[0091] The network may have antennas grouped together at the transmitter or receiver to increase throughput. This grouping of antennas may be referred to as “massive MIMO”. Massive MIMO can achieve high beamforming gain using active antenna units (AAUs). An AAU can functionally combine antennas, radio components, tower-mounted amplifiers, feed lines, and / or jumpers into a single unit. An AAU may include a separate RF chain for each antenna port. Obstacles may exist for massive MIMO. Signal transmission may be blocked by buildings, natural topography, or other obstructions. To address transmission problems caused by obstructions, the network may use a device 160 with forwarding capabilities. As another example, the network may use a device 160 with forwarding capabilities to improve the reliability of a UE 120 that is moving at high speed (e.g., to implement multiple links for the high-speed UE 120).

[0092] A RIS (Radio Reflector Array) can be a two-dimensional surface of an engineered material whose properties are reconfigurable rather than static. The engineered material may contain integrated circuits and software that enable control of the wireless medium by changing the impedance of the surface or a portion of the surface. Changes in impedance can alter the phase shift and / or reflection angle. Scattering, absorption, reflection, or diffraction characteristics can change over time and are controlled by software. The RIS can act as a reflective lens. In one example, the RIS may comprise a large array of inexpensive antennas spaced half a wavelength apart. In another example, the RIS may comprise a planar or conformal large surface based on a metamaterial, whose elements (e.g., square elements) have a size and spacing smaller than the wavelength. Each element may have a configured impedance or other surface characteristics controlled by a voltage applied to the element.

[0093] The transponderable device 160 may be or may include a planar or two-dimensional structure or surface designed to have characteristics that enable dynamic control over signals or electromagnetic waves reflected and / or redirected by the transponderable device 160. The transponderable device 160 may include one or more reconfigurable elements. For example, the transponderable device 160 may include an array of reconfigurable elements (e.g., an array of uniformly distributed reconfigurable elements). The reconfigurable elements may be elements with reconfigurable electromagnetic properties. For example, electromagnetic properties may include reflection properties (e.g., reflection coefficient), scattering properties, absorption properties, and / or diffraction properties. The electromagnetic properties of each reconfigurable element can be controlled independently and changed over time. The electromagnetic properties of each reconfigurable element can be configured independently such that combinations of configuration states of the reconfigurable elements reflect incident signals or waveforms in a controlled manner. For example, the reconfigurable elements may be configured to reflect or redirect irradiated signals in a controlled manner, such as by reflecting irradiated signals in a desired direction, with a desired beamwidth, with a desired phase, with a desired amplitude, and / or with a desired polarization, and other examples. In other words, the repeater-enabled device 160 may be able to modify one or more characteristics of the illumination signal (e.g., direction, beamwidth, phase, amplitude, and / or polarization).

[0094] The transponderable device 160, when configured to operate as a RIS (Reference Signal Reflection) system, may not have an antenna or RF chain, but may include a large number of small, low-cost components on its surface to passively reflect or refract incident signals transmitted from network node 110. The controller 410 of the transponderable device 160 can control the components on the surface, and the surface can act as a phased array. The transponderable device 160 may be a smart device configured to use a specific reflection angle for the signal. As part of the reflection configuration, network node 110 can use the controller 410 to control the reflection angle (angle of arrival of the incident wave) of the components of the transponderable device 160 by controlling the voltage to each component. θi , departure angle of the reflected wave θ r The reflection configuration may also correspond to the analog beamforming weights or coefficients provided by the repeater-capable device 160 when reflecting a signal from one device to another. The reflection configuration may also be referred to as a “repeater configuration,” “RIS reflection configuration,” “RIS reflection matrix,” or “P-MIMO configuration.” In summary, the repeater-capable device 160 helps control the propagation environment with less power consumption than an AAU.

[0095] The reconfigurable elements of the forwarding-capable device 160 can be controlled and / or configured by a controller 410 (e.g., a RIS controller). The controller 410 can be a control module (e.g., a controller and / or a processor) capable of configuring the electromagnetic characteristics of each reconfigurable element of the forwarding-capable device 160. The controller 410 can be a communication manager 170 or can be included in a communication manager. Alternatively, the communication manager 170 can be included in the controller 410. The controller 410 can be combined with similar... Figure 2 This is associated with certain components described in conjunction with UE 120, such as modem 254 and / or similar components for communicating with network node 110. Controller 410 may receive control communications (e.g., from network node 110 and / or UE 120) indicating one or more characteristics of the reflected signal (e.g., indicating desired direction, desired beamwidth, desired phase, desired amplitude, and / or desired polarization). Thus, in some examples, device 160 with forwarding capability may be able to receive communications (e.g., via device 160 with forwarding capability and / or controller 410). In some examples, device 160 with forwarding capability and / or controller 410 may not have transmitting capability (e.g., device 160 with forwarding capability may be able to reflect and / or redirect illumination signals via reconfigurable elements, but may not be able to generate and / or transmit signals). Alternatively, in some examples, the device 160 and / or controller 410 with forwarding capability may have transmitting capability (e.g., the device 160 with forwarding capability may be able to reflect and / or redirect illumination signals via reconfigurable elements, and may be able to generate and / or transmit signals). For example, the device 160 and / or controller 410 with forwarding capability may include one or more antennas and / or antenna elements for receiving and / or transmitting signals.

[0096] For example, such as Figure 4As shown, network node 110 can transmit signal 415. Signal 415 can be transmitted in a spatial direction toward device 160 with forwarding capability. Device 160 with forwarding capability can configure its reconfigurable elements to reflect and / or redirect signal 415 in a desired spatial direction and / or with one or more desired signal characteristics (e.g., beamwidth, phase, amplitude, frequency, and / or polarization).

[0097] In some examples, the reconfigurable elements (e.g., super-element) of the transponderable device 160 can be configured to reflect and / or redirect signal 415 using a reflection coefficient. For example, for incident waves in the reconfigurable elements of the transponderable device 160 n Angle of arrival θ i，n , departure angle of the reflected wave θ r，n The reflection gain of device 160 with forwarding capability can be expressed as ,in N This refers to the number of reconfigurable elements in the 160 devices with forwarding capabilities. It is the first reconfigurable element and the reconfigurable element associated with the incident wave. n The distance between them It is the first reconfigurable element and the reconfigurable element associated with the reflected wave. n The distance between them, where λ is the wavelength. j The imaginary number represents the imaginary or complex number, and It is a reconfigurable component n The reflection coefficient (e.g., where) It is the magnitude of the reflection coefficient, and (This refers to the phase of the reflection coefficient). The above equation can be associated with a general model of reflection beamforming performed by the transponder-capable device 160. For the far-field model of reflection beamforming performed by the transponder-capable device 160, the reflection gain of the transponder-capable device 160 can be expressed as... ,in d It is the distance between the reconfigurable elements of device 160 with forwarding capabilities.

[0098] As indicated by reference numeral 420, the transponder-capable device 160 may be able to reflect signal 415 in one or more spatial directions. Although in Figure 4The diagram illustrates multiple beams representing different beam states or beam directions of the forwarding-capable device 160, but the forwarding-capable device 160 may be able to reflect a signal using only one beam state or one beam direction at a time. For example, in one case, as indicated by reference numeral 425, the forwarding-capable device 160 may be configured to reflect signal 415 using a first beam state (e.g., beam state 1). "Beam state" may refer to the spatial direction and / or beam of the reflected signal (e.g., the signal reflected by the forwarding-capable device 160). The first beam state may cause signal 415 to be reflected in a spatial direction toward a first UE 120 (e.g., UE 1). As indicated by reference numeral 430, in another case, the forwarding-capable device 160 may be configured to reflect signal 415 using a second beam state (e.g., beam state 2). The second beam state may cause signal 415 to be reflected in a spatial direction toward a second UE 120 (e.g., UE 2).

[0099] A forwarding-capable device 160 can be deployed in a wireless network (such as wireless network 100) to improve communication performance and efficiency. For example, the forwarding-capable device 160 enables a transmitter (e.g., network node 110 or UE 120) to control the scattering, reflection, and refraction characteristics of the signal transmitted by the transmitter to overcome the negative effects of wireless propagation. For example, the forwarding-capable device 160 can effectively control the signal characteristics of the illuminating signal (e.g., spatial orientation, beamwidth, phase, amplitude, frequency, and / or polarization) without requiring complex decoding, encoding, and RF processing operations. Therefore, the forwarding-capable device 160 can provide increased channel diversity for signal propagation in a wireless network. Increased channel diversity provides robustness against channel fading and / or blocking, such as when network node 110 and / or UE 120 use higher frequencies (e.g., millimeter wave frequencies and / or Asia-Pacific Hertz frequencies). Furthermore, since the forwarding-capable device 160 does not need to perform complex decoding, encoding, and radio frequency processing operations, the forwarding-capable device 160 can provide a more cost- and energy-efficient way to reflect and / or redirect signals in a wireless network (e.g., compared to other mechanisms used for reflecting and / or redirecting signals, such as relay devices).

[0100] As indicated above, Figure 4 This is provided as an example. Other examples are available with reference to [the relevant information]. Figure 4 The examples described are different.

[0101] Figure 5This is a diagram illustrating an example 500 of a communication link in a wireless network including a RIS according to the present disclosure. As shown, example 500 includes a network node 110, a UE 120, and a forwarding-capable device 160. The forwarding-capable device 160 may be controlled and / or configured by a controller 410.

[0102] like Figure 5 As shown, UE 120 can directly receive communication (e.g., data and / or control information) from network node 110 as downlink communication. Alternatively or additionally, UE 120 can indirectly receive communication (e.g., data and / or control information) from network node 110 via a forwarding-capable device 160. For example, network node 110 can transmit communication in a spatial direction toward the forwarding-capable device 160, and the forwarding-capable device 160 can redirect or reflect the communication to UE 120.

[0103] In some examples, UE 120 may communicate directly with network node 110 via direct link 505. For example, communication may be sent via direct link 505. Communication sent via direct link 505 between UE 120 and network node 110 does not pass through forwarding device 160 and is not reflected, refracted, or redirected by that forwarding device. In some examples, UE 120 may communicate indirectly with network node 110 via indirect link 510 (also referred to as the RIS communication link). For example, communication may be sent via different segments of indirect link 510. Communication sent via indirect link 510 between UE 120 and network node 110 is reflected, refracted, and / or redirected by forwarding device 160. Figure 5 As shown, and as indicated by reference numeral 515, network node 110 can communicate with forwarding-capable device 160 (e.g., with controller 410) via a control channel. For example, network node 110 may indicate the spatial direction and / or signal characteristics of a signal reflected by forwarding-capable device 160 in a RIS control message. Controller 410 may configure reconfigurable elements of forwarding-capable device 160 based on the RIS control message. In some examples, the RIS control message may indicate information associated with the wireless network, such as frame structure, time synchronization information, and / or time slot boundaries, among other examples. Figure 5 The communication scheme shown can improve network performance and increase reliability by providing UE 120 with link diversity for communicating with network node 110.

[0104] In some cases, UE 120 may receive communication from network node 110 via both direct link 505 and indirect link 510 (e.g., the same communication). In some examples, UE 120 may receive communication via multiple indirect links (e.g., with or without direct link 505) associated with corresponding forwarding-capable devices 160. In other cases, network node 110 may select one of these links (e.g., direct link 505 or indirect link 510) and may use only the selected link to send communication to UE 120. Alternatively, network node 110 may receive an indication of one of these links (e.g., direct link 505 or indirect link 510) and may use only the indicated link to send communication to UE 120. UE 120 and / or forwarding-capable device 160 may send this indication. In some examples, this selection and / or indication may be based at least in part on channel conditions and / or link reliability.

[0105] In some cases, UE 120 can measure and / or estimate the Doppler frequencies of the direct and / or indirect links associated with UE 120. The Doppler effect is the phenomenon where the frequency of a wave changes as the source and observer of a wave move relative to each other. In the context of wireless communication, the source is the transmitting antenna, and the observer is the receiving antenna. The Doppler effect can cause a drift in the frequency of the received signal relative to the frequency of the transmitted signal, which can affect the accuracy of signal detection and decoding. In high-speed scenarios, the relative motion between the transmitter and receiver can cause Doppler drift in the frequency of the transmitted signal. This drift can cause the received signal to fall outside the expected frequency band, leading to errors in signal detection and decoding. Estimating the Doppler frequency allows network node 110 and / or UE 120 to mitigate the effects of Doppler drift. By knowing the Doppler frequency, network node 110 and / or UE 120 can adjust the transmitting frequency to compensate for Doppler drift and keep the received signal within the expected frequency band. This allows for more reliable and accurate signal detection and decoding, which improves the performance of the wireless communication system.

[0106] In some cases, UE 120 may individually measure each link associated with UE 120 to facilitate Doppler frequency estimation. For example, UE 120 may use a first time-domain timing to measure the direct link between UE 120 and network node 110 to facilitate Doppler frequency estimation for the direct link. In other time-domain timings, UE 120 measures the corresponding indirect link between UE 120 and network node 110 to facilitate Doppler frequency estimation for the indirect link. UE 120 may perform measurement and / or Doppler frequency estimation in different time-domain timings, allowing UE 120 to reliably identify and measure each link. Network node 110 may receive reports of measurement and / or Doppler frequency estimation. In some examples, network node 110 may estimate or determine the Doppler frequency of each link based on or in response to reports of measurement and / or Doppler frequency estimation. Network node 110 may configure (e.g., associated with indirect links) each device 160 with forwarding capabilities based on the estimated Doppler frequencies. For example, network node 110 may be configured for each device 160 with forwarding capability (e.g., each RIS) such that there are zero or only one Doppler frequency in the signal received by UE 120. This allows UE 120 to mitigate Doppler frequencies in the received signal (e.g., if multiple Doppler frequencies are present in the received signal, UE 120 may not be able to mitigate all Doppler frequencies, resulting in degraded signal detection and decoding).

[0107] However, measuring different links at appropriate time-domain times (e.g., to mitigate interference and / or measurement confusion between different links) can consume radio resources (e.g., time-domain, frequency-domain, and / or spatial-domain resources) and / or introduce delays associated with performing measurements on different links. For example, the total radio resource consumption and / or processing delay can be significant when using different radio resources to measure each link (e.g., for Doppler frequency estimation) (e.g., when UE 120 and network node 110 are communicating using numerous indirect links and / or devices with forwarding capabilities). If fewer radio resources and / or time-domain times are used to measure each link (e.g., for Doppler frequency estimation), fewer time-domain resources can be used to measure each link, resulting in less accurate and / or less reliable measurements. Therefore, the performance of Doppler frequency estimation (e.g., measurement-based) can be degraded.

[0108] Some of the techniques and apparatus described herein implement Doppler frequency estimation for RIS communication links. In some aspects, UE 120 may use shared or public radio resources to perform simultaneous Doppler frequency measurements on direct links and (e.g., those associated with RIS reflections) one or more indirect links. For example, UE 120 may receive an indication of a time-domain rotation factor associated with a corresponding RIS in one or more RISs. UE 120 may receive a corresponding reference signal via a direct link to a network node and via one or more indirect links associated with one or more RISs during a time-domain measurement. UE 120 may send a report in association with the measurement of the corresponding reference signal, indicating the estimated Doppler frequencies of the corresponding links, including the direct link and one or more indirect links, which are estimated using the time-domain rotation factor associated with the corresponding RIS.

[0109] Therefore, the amount of radio resources consumed and / or the delay associated with estimating (e.g., with RIS) the Doppler frequencies of indirect links can be reduced. For example, UE 120 can be enabled to identify the Doppler spectrum of the corresponding indirect link based on a time-domain rotation factor, thereby enabling UE 120 to use shared radio resources to perform measurements of the corresponding indirect link (e.g., the Doppler spectrum of the indirect link can be separated due to the use of the time-domain rotation factor, thereby reducing the possibility of inter-link interference and / or confusion at UE 120 regarding which measurement corresponds to which link). Furthermore, because the links use shared radio resources, the received SNR of each link can be improved.

[0110] For example, one or more indirect links are associated with reflection coefficients applied by a corresponding RIS (Reflection Spectrum Component) associated with a time-domain rotation factor. At a given time-domain timing, each RIS can reflect a signal using a reflection coefficient based on the time-domain rotation factor associated with that RIS. This allows the Doppler spectrum of the received signal at UE 120 to be separated. Therefore, UE 120 can use the corresponding Doppler spectrum (e.g., identified based on a signaling notification or configured time-domain rotation factor) to estimate the Doppler frequency of each link. For example, for an indirect link associated with a given RIS, the Doppler spectrum associated with that RIS can be a drifted version of the channel Doppler spectrum associated with the channel response, where the drift associated with the Doppler spectrum is based on the time-domain rotation factor associated with the RIS. This allows UE 120 to accurately identify the Doppler spectrum of each indirect link and / or each RIS, thereby improving the performance and / or efficiency of Doppler frequency estimation.

[0111] As indicated above, Figure 5 This is provided as an example. Other examples are available with reference to [the relevant information]. Figure 5 The examples described are different.

[0112] Figure 6 This is a diagram of Example 600 related to Doppler frequency estimation for a RIS communication link, based on this disclosure. Figure 6 As shown, one or more network nodes 110 (e.g., base stations, CUs, DUs, and / or RUs) can communicate with UE 120. In some aspects, network nodes 110 and UE 120 can communicate via one or more indirect links (e.g., associated with corresponding RISs (shown as RIS 605 and RIS 610)). In some aspects, network nodes 110, UE 120, RIS 605, and RIS 610 can be part of a wireless network (e.g., wireless network 100). UE 120 and network nodes 110 can... Figure 6 The operation shown has been performed after a wireless connection has been established.

[0113] Two RIS (e.g., RIS 605 and RIS 610) are shown as examples. The techniques and operations described herein are applicable to scenarios where network node 110 and UE 120 communicate using any number of indirect links (e.g., via one RIS, three RIS, four RIS, or another number of RIS). Additionally, a RIS is provided as an example of a device 160 with forwarding capabilities. The techniques and operations described herein are applicable to other devices 160 with forwarding capabilities and / or devices with reconfigurable elements.

[0114] As indicated by reference numeral 615 in the accompanying drawings, UE 120 may transmit a capability report associated with UE 120, and network node 110 may receive this capability report. UE 120 may transmit the capability report via UE capability signaling, UE auxiliary information (UAI) communication, uplink control information communication, RRC communication, physical uplink shared channel (PUSCH) and / or physical uplink control channel (PUCCH), and other examples. The capability report may indicate UE support for one or more operations described herein. For example, the capability report may indicate whether UE 120 supports Doppler frequency estimation for one or more links (e.g., direct links and one or more indirect links) using shared or public radio resources, as described herein.

[0115] In some aspects, the capability report may indicate whether UE 120 supports communication via a RIS or another device with forwarding capabilities. In some aspects, the capability report may indicate whether UE 120 is able to estimate the Doppler spectrum associated with the RIS and / or indirect links via channel response and time-domain rotation factors associated with the RIS and / or indirect links, as described herein. For example, the capability report may indicate whether UE 120 supports and / or is able to drift the measured or estimated channel response based on one or more configured time-domain rotation factors associated with the RIS and / or indirect links to estimate the Doppler frequency associated with the corresponding RIS and / or corresponding indirect link. In some aspects, the capability report may indicate the permissible speed associated with UE 120.

[0116] Network node 110 can configure UE 120 based on a capability report. For example, network node 110 can configure or trigger UE 120 to perform one or more operations based on, in response to, or otherwise associated with a capability report indicating that UE 120 supports one or more operations.

[0117] As indicated by reference numeral 620, network node 110 may send configuration information, and UE 120 may receive configuration information. In some aspects, UE 120 may receive configuration information via system information signaling, RRC signaling, one or more MAC control elements (MAC-CE) and / or downlink control information (DCI), and one or more other examples. In some aspects, configuration information may include indications of one or more configuration parameters for UE 120 to select and / or explicit configuration information for UE 120 to configure itself, and other examples.

[0118] In some aspects, the configuration information may instruct UE 120 to use appropriate time-domain rotation factors to estimate the Doppler frequencies of indirect links and / or RIS. In other aspects, the configuration information may instruct UE 120 to use shared or public radio resources (e.g., using public time-domain timing and / or public channel measurement resources) to estimate the Doppler frequencies of direct links and one or more indirect links. The configuration information may instruct UE 120 to use appropriate time-domain rotation factors to separate the Doppler spectra of the respective indirect links and / or RIS to estimate the Doppler frequency of each indirect link and / or each RIS.

[0119] In some aspects, configuration information may indicate one or more time-domain timings associated with Doppler frequency estimation. Time-domain timings may include one or more time-domain resources. Time-domain timings may be configured to repeat periodically over time. In some aspects, one or more time-domain timings may be associated with downlink reference signals, such as Channel State Information (CSI) Reference Signals (CSI-RS) or Tracking Reference Signals (TRS), and other examples. For example, configuration information may include a reference signal configuration (e.g., a CSI-RS resource configuration or as a TRS resource configuration) indicating one or more time-domain timings. The reference signal configuration may indicate the configuration of resources (e.g., CSI-RS resources or as TRS resources) associated with Doppler frequency measurement or estimation.

[0120] In some aspects, the configuration information may indicate a time-domain rotation factor associated with a corresponding RIS in one or more RISes (e.g., RIS 605 and RIS 610). For example, the configuration information may indicate a first time-domain rotation factor associated with RIS 605 and a second time-domain rotation factor associated with RIS 610. In other words, the configuration information may indicate a time-domain rotation factor associated with a corresponding indirect link between UE 120 and network node 110. The time-domain rotation factor may be an element or variable used by a given RIS to compute a multiplication factor to be applied to the reflection coefficients used by the given RIS. The multiplication factor may be based on the time-domain rotation factor, the index of the current time-domain timing, and / or the duration of the time-domain timing (e.g., interval length or amount of time), or otherwise associated with the time-domain rotation factor, the index of the current time-domain timing, and / or the duration of the time-domain timing (e.g., interval length or amount of time). The time-domain rotation factor and / or multiplication factor enable the Doppler spectra of different indirect links to be separated in the Doppler domain, thereby enabling UE 120 to separate and measure or estimate the Doppler frequency of each indirect link (e.g., using a reference signal transmitted by network node 110).

[0121] UE 120 can configure itself at least in part based on configuration information. In some aspects, UE 120 can be configured to perform one or more operations described herein, at least in part based on configuration information.

[0122] As indicated by reference numeral 625, network node 110 may determine one or more time-domain rotation factors. For example, network node 110 may determine the time-domain rotation factor for each RIS used by network node 110 and / or for each RIS associated with UE 120. In some aspects, network node 110 may determine the time-domain rotation factor for each indirect link (e.g., via RIS) associated with UE 120 and network node 110. For example, network node 110 may determine a first time-domain rotation factor for RIS 605 and a second time-domain rotation factor for RIS 610.

[0123] Network node 110 may determine one or more time-domain rotation factors based on or otherwise associated with the maximum Doppler frequency associated with UE 120. The maximum Doppler frequency may be the maximum value among the Doppler frequencies of all indirect links associated with UE 120 and network node 110. Network node 110 may determine the maximum Doppler frequency based on or otherwise associated with an allowed speed (e.g., maximum allowed speed) associated with UE 120. For example, the maximum Doppler frequency may be represented as... ,in It is the allowed speed (e.g., maximum allowed speed) associated with UE 120. c It is a constant (e.g., the speed of light in a vacuum), and This is the center frequency or carrier frequency. In some respects, network node 110 can determine the permissible measurable Doppler frequency (e.g., to ensure that the Doppler spectra of the direct link and each indirect link do not overlap). The permissible measurable Doppler frequency can be based on the duration of the timing of the downlink reference signal to be used for Doppler frequency estimation. T ) and the number of RIS or indirect links associated with Doppler frequency estimation ( M ), or otherwise the duration of the timing of the downlink reference signal to be used for Doppler frequency estimation. T ) and the number of RIS or indirect links associated with Doppler frequency estimation ( M This is related to the following: For example, network node 110 can determine the permissible measurable Doppler frequencies such that the permissible measurable Doppler frequencies satisfy... .

[0124] Network node 110 can be based on permissible measurable Doppler frequencies. Or it can be determined by otherwise relating it to the permissible measurable Doppler frequency. M One or more time-domain rotation factors for a RIS. For example, the time-domain rotation factor of a given RIS may be based on the RIS's index (or other identifier), the duration of the time event (…). T The number of RIS or indirect links ( M and permissible measurable Doppler frequencies Or in other ways related to the RIS index (or other identifier), the duration of the time event ( T The number of RIS or indirect links ( M This is associated with the permissible measurable Doppler frequency. For example, network node 110 can associate RIS with the permissible measurable Doppler frequency. m The time-domain rotation factor is determined as follows ,in It has an index m The time-domain twitch factor of RIS, and It is the fundamental time-domain rotation factor. Network node 110 can be based on an allowable, measurable Doppler frequency. The duration of the timing ( T The number of RIS or indirect links ( M Or in other ways with the permissible measurable Doppler frequency, the duration of the timing ( T The number of RIS or indirect links ( M The fundamental time-domain rotation factor is determined by associating these factors. For example, the fundamental time-domain rotation factor can be expressed as... Network node 110 can determine the time-domain rotation factor for each RIS and / or each indirect link in a similar manner.

[0125] As indicated by reference numeral 630 in the attached figure, network node 110 can send a first time-domain rotation factor associated with RIS 605 ( Assuming the index of RIS 605 is 1, an instruction is sent, and RIS 605 can receive (or the controller of RIS 605 can receive) this instruction. Similarly, as indicated by reference numeral 635, network node 110 can send a second time-domain rotation factor associated with RIS 610 (…). Assuming the index of RIS 605 is 2), and RIS 610 can receive (or the controller of RIS 610 can receive) this instruction. In other words, network node 110 can configure each RIS to use a different time-domain rotation factor. As described elsewhere in this document, a given RIS can use the configured time-domain rotation factor to determine the multiplication factor to be applied to the reflection coefficients used by the given RIS.

[0126] The RIS configuration can indicate the actual value of the time-domain twitch factor. For example, the RIS 605 configuration can indicate... The actual value, and the configuration of the RIS 605 can indicate. The actual value. In some other respects, the RIS configuration can indicate information that can be used to compute the time-domain twiddle factor. For example, the RIS 605 configuration can indicate the duration of a timing event ( T The number of RIS or indirect links ( M The values ​​of the indexes of RIS 605 and RIS 605. RIS 605 can be based on information indicated by network node 110 (e.g., T , M and mThe value of the first time-domain twitch factor can be determined by associating it with this information in some other way. Similarly, the RIS610 can be configured to indicate the duration of a timing event. T The number of RIS or indirect links ( M The values ​​of the indexes of RIS 610 and RIS 610. RIS 610 can be based on information indicated by network node 110 (e.g., T , M and m The actual value of the second time-domain rotation factor can be determined by associating it with the information in any other way. The indication of the time-domain rotation factor of the RIS can be conveyed via RRC signaling, MAC-CE signaling, DCI signaling, and / or combinations of signaling, as well as other examples. For example, some parameters (e.g., ...) can be indicated via RRC signaling. T The value), and some other parameters (e.g.,) can be indicated by another type of signaling (e.g., MAC-CE signaling or DCI signaling). M (value).

[0127] As shown by reference numeral 640, network node 110 may send an indication of a time-domain rotation factor associated with a corresponding RIS in one or more RISs associated with one or more indirect links between UE 120 and network node 110, and UE 120 may receive the indication. In some aspects, the indication of the time-domain rotation factor may be included in the configuration information described above. In some aspects, the indication of the time-domain rotation factor includes an indication of the value (e.g., actual value) of a corresponding time-domain rotation factor. For example, the indication of the time-domain rotation factor may include the actual value of the time-domain rotation factor. In other aspects, the indication of the time-domain rotation factor includes information that can be used to calculate the time-domain rotation factor. For example, the indication of the time-domain rotation factor may include the duration of the time-domain measurement timing (…). T ), number of one or more RIS ( M The UE 120 may calculate the time-domain rotation factor of the RIS and / or indirect links based on information indicated by the network node 110 or otherwise associated with that information (e.g., using one or more of the formulas described herein). The UE 120's indication of the time-domain rotation factor may be conveyed via RRC signaling, MAC-CE signaling, DCI signaling and / or combinations of signaling, and other examples. For example, some parameters (e.g., T The value of ( ) can be indicated to UE 120 via RRC signaling, while some other parameters (e.g., M The value can be indicated to the UE 120 by another type of signaling (e.g., MAC-CE signaling or DCI signaling).

[0128] As indicated by reference numeral 645, network node 110 may transmit a reference signal (e.g., CSI-RS, TRS, or another reference signal) during time-domain timing (e.g., measurement time-domain timing or channel measurement time-domain timing). Network node 110 may transmit the reference signal to UE 120 via a direct link and via one or more indirect links (e.g., a first indirect link associated with RIS 605 and a second indirect link associated with RIS 610). Figure 8 As shown, reference signals can be transmitted using shared or public radio resources via a direct link and via one or more indirect links. For example, reference signals can be transmitted via a direct link and via one or more indirect links during the same time-domain period.

[0129] As indicated by reference numeral 650 in the accompanying drawings, the RIS 605 may reflect, redirect, and / or refract a reference signal to the UE 120. For example, the RIS 605 may use a first time-domain rotation factor (e.g., It can reflect, redirect, refract, and / or otherwise forward reference signals. For example, the RIS 605 can be used for time-domain timing. l (For example, where) l This is an index of the time-domain timing (which is used to operate on or determine the multiplication factor to be used in the operation of the reflection coefficients used by the RIS 605). For example, the RIS 605 can be based on the current time-domain timing. l First time-domain rotation factor and / or the duration of time-domain measurement opportunities T Or in other ways related to the current time domain timing l The duration of the first time-domain rotation factor and / or the timing of the time-domain measurement. T The correlation is used to calculate or determine the multiplication factor. For example, the RIS 605's correlation with time-domain timing. l The associated multiplication factor can be represented as More generally, RIS m and timing l The associated multiplication factor can be represented as The RIS 605 may multiply the reflection coefficients (e.g., the reflection coefficients associated with the angle of incidence from network node 110 to RIS 605 and the angle of reflection from RIS 605 to UE 120) by a multiplication factor or otherwise modify the reflection coefficients, either by the RIS 605 operation or configured for the RIS.

[0130] For example, the RIS 605 can modify the reflection coefficient as follows: ,in It is a reconfigurable component (or a super-component). n The modified reflection coefficient, and It is a reconfigurable component (or a super-component). n The reflection coefficient. As described elsewhere in this document, the original reflection coefficient of each reconfigurable element. It can be derived based on the angle of incidence and the angle of reflection, as described elsewhere in this document. The original reflection coefficient can be obtained during the measurement duration associated with the Doppler frequency estimation (e.g., The RIS remains constant during this period (e.g., to ensure the reference signal is correctly reflected in the spatial direction toward UE 120). More generally, RIS m The modified reflection coefficient can be expressed as .

[0131] As indicated by reference numeral 655 in the accompanying drawings, the RIS 610 can reflect, redirect, and / or refract a reference signal to the UE 120. For example, the RIS 610 may use a second time-domain rotation factor (e.g., It can reflect, redirect, refract, and / or otherwise forward the reference signal. For example, the RIS 610 can be tailored to time-domain timing. l The calculation or determination of the multiplication factor to be used in the calculation of the reflection coefficients used by the RIS 610. For example, the RIS 610 may base its calculation on the current time-domain timing. l Second time-domain rotation factor and / or the duration of time-domain measurement opportunities T Or in other ways related to the current time domain timing l The duration of the second time-domain rotation factor and / or the timing of time-domain measurements. T The correlation is used to calculate or determine the multiplication factor. For example, the RIS 610's correlation with time-domain timing. l The associated multiplication factor can be represented as The RIS 610 may modify the reflection coefficients (e.g., the reflection coefficients associated with the angle of incidence from network node 110 to RIS 610 and the angle of reflection from RIS 610 to UE 120, using the formula described elsewhere herein) by multiplying by a multiplication factor or otherwise. For example, the RIS 610 may modify the reflection coefficients as follows: ,in It is a reconfigurable component (or a super-component). n The modified reflection coefficient, and It is a reconfigurable component (or a super-component). n The reflection coefficient. As described elsewhere in this document, the original reflection coefficient of each reconfigurable element. It can be derived based on the angle of incidence and the angle of reflection as described elsewhere in this article.

[0132] As indicated by reference numeral 660 in the accompanying figure, UE 120 can estimate the Doppler frequencies of the direct link and one or more indirect links. UE 120 can estimate the Doppler frequencies of one or more indirect links based on or otherwise associated with a corresponding time-domain rotation factor. For example, UE 120 can estimate the channel response associated with a corresponding reference signal (e.g., transmitted by network node 110 and / or reflected by RIS) and the corresponding link. For example, UE 120 can estimate the channel response based on the original reference symbol associated with the reference signal. Alternatively, the channel response can be estimated by associating it with the original reference symbol in other ways, where k It is a subcarrier, and l This refers to the current time domain timing. The estimated channel response may include information associated with direct links and one or more indirect links. For example, the resulting overall equivalent channel response (e.g., by measuring the original reference symbol) The estimated value can be expressed as: ,in and Subcarriers k and RIS m Timing l The original channel response and the equivalent channel response at the location. This is because of the rotation of the reflection coefficients applied by RIS (e.g., in the time domain), as described in more detail elsewhere in this document. UE 120 can estimate the reflection coefficients at all subcarriers and at the appropriate time points. l The channel response during the period. For example, the combined or summed channel response can be represented as... ,in K It is the number of subcarriers associated with the reference signal.

[0133] UE 120 can estimate the Doppler spectrum associated with each RIS and / or each indirect link via the channel response and the time-domain rotation factor associated with that RIS and / or the indirect link. For example, UE 120 can compute the Doppler frequencies of the direct link and each indirect link at their respective equivalent Doppler spectra. UE 120 can estimate or derive the Doppler spectrum of the estimated channel response at multiple (L) time-domain moments for each link by performing an FFT operation on the overall equivalent channel response vector (e.g., a vector comprising estimated channel responses at multiple time-domain moments). For example, the overall equivalent channel response vector could be... or .

[0134] For indirect links, UE 120 can determine the connection with RIS. m Multiple timings of related indirect links L and subcarriersk The original channel response vector at is UE 120 can be identified as related to RIS. m Multiple timings of related indirect links L and multiple subcarriers K The original channel response vector at is UE 120 can determine its relationship with RIS. m Multiple timings of related indirect links L and subcarriers k The equivalent channel response vector at is Similarly, UE 120 can determine the relationship with RIS. m Multiple timings of related indirect links L and multiple subcarriers K The equivalent channel response vector at is .

[0135] UE 120 can determine that, for RIS m Related indirect links, Doppler spectrum or It is the Doppler spectrum or A drifting version. In other words, UE 120 can estimate or determine the Doppler spectrum. or UE 120 can drift the estimated or determined Doppler spectrum (e.g., where the drift is based on RIS). m (Associated with the time-domain rotation factor or otherwise associated with it) to obtain the relationship with RIS. m The associated indirect link is associated with the Doppler spectrum. For example, the Doppler spectrum. It can be represented as Doppler spectrum It can be represented as Doppler spectrum It can be represented as Similarly, the Doppler spectrum It can be represented as Frequency domain elements l It can be represented as and In other words, the Doppler spectrum of the indirect link associated with RIS m can be a value (or length). Drift. UE 120 can determine that the Doppler spectrum of the direct link is not drifted (e.g., because no time-domain rotation factor is applied to the transmission of the reference signal via the direct link).

[0136] because Furthermore, because different RIS apply different time-domain rotation factors (e.g., with different lengths or values ​​of Doppler spectrum shift), the Doppler spectra of the corresponding links (e.g., direct links and one or more indirect links) can be non-overlapping. Therefore, when RIS simultaneously reflect the reference signal using different time-domain rotation factors, interference in the corresponding Doppler spectra can be mitigated or eliminated. Additionally, because the derived Doppler spectrum of the estimated channel response can be of varying lengths... The cascading allows UE 120 to identify the Doppler spectrum of both the direct and indirect links from the derived Doppler spectrum.

[0137] UE 120 can estimate the Doppler frequency based on the corresponding Doppler spectrum. For example, the estimated Doppler frequency associated with the RIS is based on the Doppler spectrum associated with the RIS (e.g., derived from the estimated channel response Doppler spectrum as described above). For example, the Doppler frequency of the corresponding indirect link can be associated with the highest received power within the corresponding Doppler spectrum. For example, UE 120 can determine that the Doppler frequency associated with a given indirect link (e.g., and a given RIS associated with the given indirect link) is a frequency value with the highest power in the Doppler spectrum associated with the given indirect link. As another example, the Doppler frequency of the indirect link associated with the RIS can be based on, or otherwise associated with, the inverse discrete Fourier transform (iDFT) of the drifted version of the Doppler spectrum associated with the indirect link. The drift associated with the drifted version of the Doppler spectrum can be associated with a time-domain rotation factor associated with the RIS. For example, UE 120 can value The Doppler spectrum of the drift RIS m. UE 120 can perform an iDFT operation associated with the drifter's Doppler spectrum to obtain an interference-free time-domain signal. The estimated Doppler frequency can be associated with the slope value of the phase of the time-domain signal.

[0138] As shown by reference numeral 665, UE 120 may send an indication of the estimated Doppler frequencies of a direct link and one or more indirect links, and network node 110 may receive the indication. For example, UE 120 may send a report indicating the estimated Doppler frequencies of the respective links including the direct link and one or more indirect links, and network node 110 may receive the report. Network node 110 may configure RIS (e.g., RIS 605 and / or RIS 610) based on, in response to, or otherwise associated with these estimated Doppler frequencies (e.g., such that zero or only one Doppler frequency exists in the signal received by UE 120).

[0139] As indicated above, Figure 6 This is provided as an example. Other examples are available with reference to [the relevant information]. Figure 6 The examples described are different.

[0140] Figure 7 This is a diagram of Example 700 related to Doppler frequency estimation for a RIS communication link, based on this disclosure. Figure 7 As shown, different RIS can apply different multiplication factors to the reflection coefficient at a given time-domain timing to facilitate efficient Doppler frequency estimation of UE 120.

[0141] For example, UE 120 can G Doppler frequency estimation is performed at each time-domain opportunity. For example... Figure 7 As shown, the multiplication factor applied by a given RIS during a given time-domain timing period can be based on the index of the time-domain timing and the time-domain rotation factor associated with the given RIS, or otherwise associated with the index of the time-domain timing and the time-domain rotation factor associated with the given RIS. For example, RIS 605 can apply the multiplication factor during time timing 1. Apply during time slot 2 Apply during time opportunity 3 Apply during time slot 4 And at the right time G Application during period Similarly, the RIS 610 can apply the multiplication factor during timing 1. Apply during time slot 2 Apply during time opportunity 3 Apply during time slot 4 And at the right time G Application during period .

[0142] Therefore, the received signal at UE 120 can be associated with the drifting, non-overlapping Doppler spectrum of the corresponding link (e.g., including direct links and one or more indirect links). For example, as Figure 7 As shown, the received signal can be associated with the Doppler spectrum 705 of the direct link, the Doppler spectrum 710 of indirect link 1 (e.g., associated with RIS 605), and the Doppler spectrum 715 of indirect link 2 (e.g., associated with RIS 610). The Doppler spectrum 710 can be derived from the Doppler frequency... Crossing to (For example, a reference center or reference Doppler frequency). The Doppler spectrum 710 can be obtained from the Doppler frequency. Crossing to The Doppler spectrum 715 can be obtained from the Doppler frequency. Crossing to UE 120 may (e.g., using Doppler spectrum 705) estimate or determine that Doppler frequency 720 is associated with a direct link. UE 120 may (e.g., using Doppler spectrum 710) estimate or determine that Doppler frequency 725 is associated with indirect link 1. Similarly, UE 120 may (e.g., using Doppler spectrum 715) estimate or determine that Doppler frequency 730 is associated with indirect link 2.

[0143] As indicated above, Figure 7 This is provided as an example. Other examples are available with reference to [the relevant information]. Figure 7 The examples described are different.

[0144] Figure 8 This is a diagram illustrating an example procedure 800 performed by a UE according to this disclosure. Example procedure 800 is an example in which a UE (e.g., UE 120) performs operations associated with Doppler frequency estimation for a RIS communication link.

[0145] like Figure 8 As shown, in some aspects, process 800 may include receiving from a network node an indication of a time-domain rotation factor associated with a respective RIS in one or more RISes (box 810). For example, the UE (e.g., using...) Figure 11 The depicted receiving component 1102 and / or communication manager 1106 can receive from the network node an indication of the time-domain rotation factor associated with a corresponding RIS in one or more RIS, as described above.

[0146] like Figure 8 As further shown, in some aspects, process 800 may include receiving a corresponding reference signal (block 820) during a time-domain measurement opportunity via a direct link to a network node and via one or more indirect links associated with one or more RIS. For example, the UE (e.g., using...) Figure 11 The described receiving component 1102 and / or communication manager 1106 can receive the corresponding reference signal during time-domain measurement opportunities via a direct link to a network node and via one or more indirect links associated with one or more RIS, as described above.

[0147] like Figure 8 Further, as shown, in some aspects, process 800 may include sending a report to a network node that, in association with measurements of a corresponding reference signal, indicates estimated Doppler frequencies of a corresponding link, including a direct link and one or more indirect links, which are estimated using a time-domain rotation factor associated with the corresponding RIS (box 830). For example, the UE (e.g., using...) Figure 11The depicted transmitting component 1104 and / or communication manager 1106 can send a report to a network node that, in association with a measurement of the corresponding reference signal, indicates the estimated Doppler frequencies of the corresponding links, including direct links and one or more indirect links, which are estimated using a time-domain rotation factor associated with the corresponding RIS, as described above.

[0148] Process 800 may include additional aspects, such as any single aspect or any combination of aspects described below and / or in conjunction with one or more other process descriptions elsewhere herein.

[0149] In the first aspect, one or more indirect links are associated with the reflection coefficient of a corresponding RIS application associated with a time-domain rotation factor.

[0150] In the second aspect, either alone or in combination with the first aspect, the time-domain rotation factor is based on the number of one or more RIS and the maximum Doppler frequency associated with the direct link and one or more indirect links.

[0151] In the third aspect, either alone or in combination with one or more of the first and second aspects, the time-domain rotation factor is based on the number of one or more RIS, the duration of the time-domain measurement timing, and the index value of the corresponding RIS.

[0152] In the fourth aspect, either alone or in combination with one or more of the first to third aspects, the indication of the time-domain rotation factor includes the indication of the value of the corresponding time-domain rotation factor in the time-domain rotation factors.

[0153] In the fifth aspect, either alone or in combination with one or more of the first to fourth aspects, the indication of the time-domain rotation factor includes the duration of the time-domain measurement timing, the number of one or more RIS, and the index value of one or more RIS.

[0154] In the sixth aspect, either alone or in combination with one or more of the first to fifth aspects, the indication of the time-domain rotation factor is included in at least one of radio resource control communications, MAC-CE communications, or downlink control information communications.

[0155] In the seventh aspect, either alone or in combination with one or more of the first to sixth aspects, process 800 includes: estimating the channel response associated with the corresponding reference signal and the corresponding link; and for one or more RIS, estimating the Doppler spectrum associated with the RIS via the channel response and a time-domain rotation factor associated with the RIS, wherein the estimated Doppler frequencies associated with the RIS are based on the Doppler spectrum associated with the RIS.

[0156] In the eighth aspect, either alone or in combination with one or more of the first to seventh aspects, the Doppler spectrum associated with RIS is a drifted version of the channel Doppler spectrum associated with the channel response, wherein the drift associated with the Doppler spectrum is based on the time-domain rotation factor associated with RIS.

[0157] In the ninth aspect, either alone or in combination with one or more of the first to eighth aspects, one or more indirect links are associated with corresponding Doppler spectra that reflect the corresponding reference signals without overlap using a time-domain rotation factor based on one or more RIS, and wherein the Doppler frequency of the corresponding indirect link in the estimated Doppler frequency is associated with the corresponding Doppler spectrum.

[0158] In the tenth aspect, alone or in combination with one or more of the first to ninth aspects, one or more indirect links are associated with the corresponding Doppler spectrum, and wherein the Doppler frequency of the corresponding indirect link in the estimated Doppler frequency is associated with the highest received power within the corresponding Doppler spectrum.

[0159] In the eleventh aspect, individually or in combination with one or more of the first to tenth aspects, one or more indirect links are associated with a corresponding Doppler spectrum, wherein the Doppler frequency of the indirect link associated with the RIS in one or more RIS is estimated based on the inverse discrete Fourier transform of a drift version of the Doppler spectrum associated with the indirect link in the corresponding Doppler spectrum, and wherein the drift associated with the drift version of the Doppler spectrum is associated with a time-domain rotation factor associated with the RIS in the time-domain rotation factor.

[0160] In the twelfth aspect, individually or in combination with one or more of the first to eleventh aspects, each of the corresponding reference signals includes a tracking reference signal or a channel state information reference signal.

[0161] although Figure 8 An example box of process 800 is shown, but in some respects, process 800 may include... Figure 8 The boxes depicted may be fewer, different, or arranged differently compared to additional boxes. Alternatively, two or more boxes in the process 800 may be executed in parallel.

[0162] Figure 9 This is a diagram illustrating an example process 900 performed, for example, by a network node according to this disclosure. Example process 900 is an example in which a network node (e.g., network node 110) performs operations associated with Doppler frequency estimation for a RIS communication link.

[0163] like Figure 9As shown, in some aspects, process 900 may include sending an indication (box 910) to the UE and one or more RIS of a time-domain rotation factor associated with a corresponding RIS among the one or more RIS. For example, a network node (e.g., using...) Figure 12 The depicted transmitting component 1204 and / or communication manager 1206 can transmit instructions to the UE and one or more RIS regarding the time-domain rotation factor associated with the corresponding RIS in one or more RIS, as described above.

[0164] like Figure 9 As further shown, in some aspects, process 900 may include transmitting a reference signal (block 920) during a time-domain measurement opportunity via a direct link to the UE and via one or more indirect links associated with one or more RIS. For example, a network node (e.g., using...) Figure 12 The transmission component 1204 and / or communication manager 1206 depicted may transmit reference signals during time-domain measurement opportunities via a direct link to the UE and via one or more indirect links associated with one or more RIS, as described above.

[0165] like Figure 9 Further, as shown, in some aspects, process 900 may include receiving a report associated with the UE, which, in association with measurements of a reference signal, indicates estimated Doppler frequencies of corresponding links, including direct links and one or more indirect links, which are estimated using a time-domain rotation factor associated with the corresponding RIS (box 930). For example, network nodes (e.g., using...) Figure 12 The depicted receiving component 1202 and / or communication manager 1206 can receive a report associated with the UE, which, in association with a measurement of the reference signal, indicates the estimated Doppler frequencies of the respective links, including direct links and one or more indirect links, which are estimated using a time-domain rotation factor associated with the respective RIS, as described above.

[0166] Process 900 may include additional aspects, such as any single aspect or any combination of aspects described below and / or in conjunction with one or more other process descriptions elsewhere herein.

[0167] In the first aspect, one or more indirect links are associated with the reflection coefficient of a corresponding RIS application associated with a time-domain rotation factor.

[0168] In the second aspect, either alone or in combination with the first aspect, the time-domain rotation factor is based on the number of one or more RIS and the maximum Doppler frequency associated with the direct link and one or more indirect links.

[0169] In the third aspect, either alone or in combination with one or more of the first and second aspects, the maximum Doppler frequency is associated with the permissible speed of the UE.

[0170] In the fourth aspect, either alone or in combination with one or more of the first to third aspects, the time-domain rotation factor is based on the number of one or more RIS, the duration of the time-domain measurement timing, and the index value of the corresponding RIS.

[0171] In the fifth aspect, either alone or in combination with one or more of the first to fourth aspects, the indication of the time-domain rotation factor includes the indication of the value of the corresponding time-domain rotation factor in the time-domain rotation factors.

[0172] In the sixth aspect, either alone or in combination with one or more of the first to fifth aspects, the indication of the time-domain rotation factor includes the duration of the time-domain measurement timing, the number of one or more RIS, and the index value of one or more RIS.

[0173] In the seventh aspect, either alone or in combination with one or more of the first to sixth aspects, the indication of the time-domain rotation factor is included in at least one of radio resource control communications, MAC-CE communications, or downlink control information communications.

[0174] In the eighth aspect, either alone or in combination with one or more of the first to seventh aspects, the corresponding reference signal includes a tracking reference signal or a channel state information reference signal.

[0175] although Figure 9 An example box of process 900 is shown, but in some respects, process 900 may include... Figure 9 The boxes depicted may be fewer, different, or arranged differently compared to additional boxes. Alternatively, two or more boxes in the process 900 may be executed in parallel.

[0176] Figure 10 This is a diagram illustrating an example process 1000 performed, for example, by a RIS according to this disclosure. Example process 1000 is an example in which a RIS (e.g., RIS 605, RIS 610, a forwarding device 160, or a controller of the RIS) performs operations associated with Doppler frequency estimation for a RIS communication link.

[0177] like Figure 10 As shown, in some aspects, process 1000 may include receiving an indication from a network node of a time-domain rotation factor associated with the RIS (box 1010). For example, the RIS (e.g., using...) Figure 13The depicted receiving component 1302 and / or communication manager 1306 can receive an indication of the time-domain rotation factor associated with the RIS from the network node, as described above.

[0178] like Figure 10 Further shown, in some aspects, process 1000 may include using a reflection coefficient to reflect a reference signal associated with a network node, the reflection coefficient being based on a time-domain rotation factor (box 1020). For example, RIS (e.g., using...) Figure 13 The depicted communication manager 1306 can use a reflection coefficient to reflect a reference signal associated with a network node, which is based on a time-domain rotation factor, as described above.

[0179] Process 1000 may include additional aspects, such as any single aspect or any combination of aspects described below and / or in conjunction with one or more other process descriptions elsewhere herein.

[0180] In the first aspect, the time-domain rotation factor is based on the number of one or more RIS including RIS and the maximum Doppler frequency associated with the network node.

[0181] In the second aspect, either alone or in combination with the first aspect, the time-domain rotation factor is based on the number of one or more RIS including the reflected reference signal of the RIS, the duration of the time-domain measurement timing, and the index value of the RIS.

[0182] In the third aspect, either alone or in combination with one or more of the first and second aspects, the indication of the time-domain rotation factor includes the indication of the value of the time-domain rotation factor.

[0183] In the fourth aspect, either alone or in combination with one or more of the first to third aspects, the indication of the time-domain rotation factor includes an indication of the duration of the time-domain measurement timing, the number of one or more RIS of the reflected reference signal, and the index value of the RIS.

[0184] In the fifth aspect, either alone or in combination with one or more of the first to fourth aspects, the indication of the time-domain rotation factor is included in at least one of radio resource control communications, MAC control element communications, or downlink control information communications.

[0185] In the sixth aspect, alone or in combination with one or more of the first to fifth aspects, the reference signal includes a tracking reference signal or a channel state information reference signal.

[0186] although Figure 10 An example box of process 1000 is shown, but in some respects, process 1000 may include... Figure 10The boxes depicted may be fewer, different, or arranged differently compared to additional boxes. Alternatively, two or more boxes in the process 1000 may be executed in parallel.

[0187] Figure 11 This is a diagram of an example device 1100 for wireless communication according to the present disclosure. Device 1100 may be a UE, or a UE may include device 1100. In some aspects, device 1100 includes a receiving component 1102, a transmitting component 1104, and / or a communication manager 1106 that can communicate with each other (e.g., via one or more buses and / or one or more other components). In some aspects, communication manager 1106 is combined with... Figure 1 The described communication manager 140. As shown, device 1100 can communicate with another device 1108 (such as a UE or a network node (such as a CU, DU, RU or base station)) using receiving component 1102 and transmitting component 1104.

[0188] In some respects, device 1100 can be configured to perform the functions described herein. Figure 6 and Figure 7 One or more operations as described herein. Additionally or alternatively, device 1100 may be configured to perform one or more processes as described herein, such as Figure 8 The process 800 or a combination thereof. In some respects, Figure 11 The illustrated device 1100 and / or one or more components may include a combination Figure 2 One or more components of the described UE. Additionally or alternatively, may be combined... Figure 2 The described implementation within one or more components Figure 11 One or more components are shown. Additionally or alternatively, one or more of the components in a set may be implemented at least partially as software stored in memory. For example, a component (or a portion of a component) may be implemented as instructions or code stored in a non-transitory computer-readable medium and executable by a controller or processor to perform the function or operation of the component.

[0189] Receiver 1102 may receive communications from device 1108, such as reference signals, control information, data communications, or combinations thereof. Receiver 1102 may provide the received communications to one or more other components of device 1100. In some aspects, receiver 1102 may perform signal processing on the received communications (such as filtering, amplification, demodulation, analog-to-digital conversion, demultiplexing, deinterleaving, demapping, equalization, interference cancellation, or decoding, and other examples), and may provide the processed signals to one or more other components of device 1100. In some aspects, receiver 1102 may include combinations of... Figure 2The described UE includes one or more antennas, modems, demodulators, MIMO detectors, receiver processors, controllers / processors, memory, or combinations thereof.

[0190] Transmitting component 1104 may transmit communications, such as reference signals, control information, data communications, or combinations thereof, to device 1108. In some aspects, one or more other components of device 1100 may generate communications and provide the generated communications to transmitting component 1104 for transmission to device 1108. In some aspects, transmitting component 1104 may perform signal processing (such as filtering, amplification, modulation, digital-to-analog conversion, multiplexing, interleaving, mapping, or encoding, and other examples) on the generated communications and may transmit the processed signals to device 1108. In some aspects, transmitting component 1104 may include combinations of... Figure 2 The described UE includes one or more antennas, modems, modulators, transmit MIMO processors, transmit processors, controllers / processors, memory, or combinations thereof. In some aspects, transmit component 1104 may be co-located with receive component 1102 in a transceiver.

[0191] The communication manager 1106 may support the operation of the receiving component 1102 and / or the transmitting component 1104. For example, the communication manager 1106 may receive information associated with configuring the reception of communications by the receiving component 1102 and / or the transmission of communications by the transmitting component 1104. Additionally or alternatively, the communication manager 1106 may generate control information and / or provide control information to the receiving component 1102 and / or the transmitting component 1104 to control the reception and / or transmission of communications.

[0192] The receiving component 1102 can receive from the network node an indication of a time-domain rotation factor associated with a corresponding RIS in one or more RISs. The receiving component 1102 can receive a corresponding reference signal during a time-domain measurement opportunity via a direct link to the network node and via one or more indirect links associated with the one or more RISs. The transmitting component 1104 can send a report to the network node in association with a measurement of the corresponding reference signal, indicating estimated Doppler frequencies of the corresponding links, including the direct links and one or more indirect links, which are estimated using the time-domain rotation factor associated with the corresponding RIS.

[0193] The communication manager 1106 can estimate the channel response associated with the corresponding reference signal and the corresponding link.

[0194] The communication manager 1106 can estimate the Doppler spectrum associated with one or more RISs via the channel response and the time-domain rotation factor associated with the RIS, wherein the estimated Doppler frequencies associated with the RIS are based on the Doppler spectrum associated with the RIS.

[0195] Figure 11 The number and arrangement of components shown are provided as an example. In reality, they can exist in... Figure 11 The components shown are compared to additional components, fewer components, different components, or components arranged in a different manner. Furthermore, Figure 11 The two or more components shown can be implemented within a single component, or Figure 11 The single component shown can be implemented as multiple distributed components. Additionally or alternatively, Figure 11 The set (one or more) components shown are executable and described as being composed of Figure 11 The other set of components shown performs one or more functions.

[0196] Figure 12 This is a diagram of an example device 1200 for wireless communication according to the present disclosure. Device 1200 may be a network node, or a network node may include device 1200. In some aspects, device 1200 includes a receiving component 1202, a transmitting component 1204, and / or a communication manager 1206 that can communicate with each other (e.g., via one or more buses and / or one or more other components). In some aspects, communication manager 1206 is combined with... Figure 1 The described communication manager 150. As shown, device 1200 can communicate with another device 1208 (such as a UE or a network node (such as a CU, DU, RU or base station)) using receiving component 1202 and transmitting component 1204.

[0197] In some respects, device 1200 can be configured to perform the functions described herein. Figure 6 and Figure 7 One or more operations as described herein. Additionally or alternatively, the apparatus 1200 may be configured to perform one or more processes as described herein, such as Figure 9 The process 900 or a combination thereof. In some respects, Figure 12 The illustrated device 1200 and / or one or more components may include a combination Figure 2 One or more components of the described network node. Additionally or alternatively, they may be combined... Figure 2 The described implementation within one or more components Figure 12One or more components are shown. Additionally or alternatively, one or more of the components in a set may be implemented at least partially as software stored in memory. For example, a component (or a portion of a component) may be implemented as instructions or code stored in a non-transitory computer-readable medium and executable by a controller or processor to perform the function or operation of the component.

[0198] Receiver 1202 may receive communications from device 1208, such as reference signals, control information, data communications, or combinations thereof. Receiver 1202 may provide the received communications to one or more other components of device 1200. In some aspects, receiver 1202 may perform signal processing on the received communications (such as filtering, amplification, demodulation, analog-to-digital conversion, demultiplexing, deinterleaving, demapping, equalization, interference cancellation, or decoding, and other examples), and may provide the processed signals to one or more other components of device 1200. In some aspects, receiver 1202 may include combinations of... Figure 2 The described network node includes one or more antennas, modems, demodulators, MIMO detectors, receiver processors, controllers / processors, memory, or combinations thereof. In some aspects, receiver component 1202 and / or transmitter component 1204 may include or be included in a network interface. The network interface may be configured to acquire and / or output signals for device 1200 via one or more communication links, such as backhaul links, midhaul links, and / or fronthaul links.

[0199] Transmitting component 1204 may transmit communications, such as reference signals, control information, data communications, or combinations thereof, to device 1208. In some aspects, one or more other components of device 1200 may generate communications and provide the generated communications to transmitting component 1204 for transmission to device 1208. In some aspects, transmitting component 1204 may perform signal processing (such as filtering, amplification, modulation, digital-to-analog conversion, multiplexing, interleaving, mapping, or encoding, and other examples) on the generated communications and may transmit the processed signals to device 1208. In some aspects, transmitting component 1204 may include combinations of... Figure 2 The described network node includes one or more antennas, modems, modulators, transmit MIMO processors, transmit processors, controllers / processors, memory, or combinations thereof. In some aspects, the transmit component 1204 may be co-located with the receive component 1202 in a transceiver.

[0200] The communication manager 1206 may support the operation of the receiving component 1202 and / or the transmitting component 1204. For example, the communication manager 1206 may receive information associated with configuring the reception of communications by the receiving component 1202 and / or the transmission of communications by the transmitting component 1204. Additionally or alternatively, the communication manager 1206 may generate control information and / or provide control information to the receiving component 1202 and / or the transmitting component 1204 to control the reception and / or transmission of communications.

[0201] Transmitting component 1204 can transmit an indication of a time-domain rotation factor associated with a corresponding RIS in the one or more RISs to the UE and one or more RISs. Transmitting component 1204 can transmit a reference signal during a time-domain measurement opportunity via a direct link to the UE and via one or more indirect links associated with the one or more RISs. Receiving component 1202 can receive a report associated with the UE that, in connection with the measurement of the reference signal, indicates estimated Doppler frequencies of the corresponding links, including the direct link and one or more indirect links, which are estimated using the time-domain rotation factor associated with the corresponding RIS.

[0202] Figure 12 The number and arrangement of components shown are provided as an example. In reality, they can exist in... Figure 12 The components shown are compared to additional components, fewer components, different components, or components arranged in a different manner. Furthermore, Figure 12 The two or more components shown can be implemented within a single component, or Figure 12 The single component shown can be implemented as multiple distributed components. Additionally or alternatively, Figure 12 The set (one or more) components shown are executable and described as being composed of Figure 12 The other set of components shown performs one or more functions.

[0203] Figure 13 This is a diagram of an example device 1300 for wireless communication according to the present disclosure. Device 1300 may be a RIS (or another device with forwarding capability), or a RIS (e.g., or another device with forwarding capability) may include device 1300. In some aspects, device 1300 includes a receiving component 1302, a transmitting component 1304, and / or a communication manager 1306 that can communicate with each other (e.g., via one or more buses and / or one or more other components). In some aspects, the communication manager 1306 is combined with... Figure 1 The described communication manager 170. As shown, device 1300 can communicate with another device 1308 (such as a UE or a network node (such as a CU, DU, RU or base station)) using receiving component 1302 and transmitting component 1304.

[0204] In some respects, device 1300 can be configured to perform the functions described herein. Figure 6 and Figure 7 One or more operations as described herein. Additionally or alternatively, device 1300 may be configured to perform one or more processes described herein, such as Figure 10 The process 1000 or a combination thereof. In some respects, Figure 13 The illustrated device 1300 and / or one or more components may include a combination Figure 2 One or more components of the described RIS. Additionally or alternatively, may be combined... Figure 2 The described implementation within one or more components Figure 13 One or more components are shown. Additionally or alternatively, one or more of the components in a set may be implemented at least partially as software stored in memory. For example, a component (or a portion of a component) may be implemented as instructions or code stored in a non-transitory computer-readable medium and executable by a controller or processor to perform the function or operation of the component.

[0205] Receiver 1302 may receive communications from device 1308, such as reference signals, control information, data communications, or combinations thereof. Receiver 1302 may provide the received communications to one or more other components of device 1300. In some aspects, receiver 1302 may perform signal processing on the received communications (such as filtering, amplification, demodulation, analog-to-digital conversion, demultiplexing, deinterleaving, demapping, equalization, interference cancellation, or decoding, and other examples), and may provide the processed signals to one or more other components of device 1300. In some aspects, receiver 1302 may include combinations of... Figure 2 The described RIS (e.g., a device with forwarding capability) includes one or more antennas, modems, demodulators, MIMO detectors, receiver processors, controllers / processors, memory, or combinations thereof.

[0206] Transmitting component 1304 may transmit communications, such as reference signals, control information, data communications, or combinations thereof, to device 1308. In some aspects, one or more other components of device 1300 may generate communications and provide the generated communications to transmitting component 1304 for transmission to device 1308. In some aspects, transmitting component 1304 may perform signal processing (such as filtering, amplification, modulation, digital-to-analog conversion, multiplexing, interleaving, mapping, or encoding, and other examples) on the generated communications and may transmit the processed signals to device 1308. In some aspects, transmitting component 1304 may include combinations of... Figure 2The described RIS (e.g., a device with repeater capability) includes one or more antennas, modems, modulators, transmit MIMO processors, transmit processors, controllers / processors, memories, or combinations thereof. In some aspects, the transmit component 1304 may be co-located with the receive component 1302 in a transceiver.

[0207] The communication manager 1306 may support the operation of the receiving component 1302 and / or the transmitting component 1304. For example, the communication manager 1306 may receive information associated with configuring the reception of communications by the receiving component 1302 and / or the transmission of communications by the transmitting component 1304. Additionally or alternatively, the communication manager 1306 may generate control information and / or provide control information to the receiving component 1302 and / or the transmitting component 1304 to control the reception and / or transmission of communications.

[0208] The receiving component 1302 can receive an indication of the time-domain rotation factor associated with the RIS from the network node. The communication manager 1306 can use a reflection coefficient based on the time-domain rotation factor to reflect the reference signal associated with the network node.

[0209] Figure 13 The number and arrangement of components shown are provided as an example. In reality, they can exist in... Figure 13 The components shown are compared to additional components, fewer components, different components, or components arranged in a different manner. Furthermore, Figure 13 The two or more components shown can be implemented within a single component, or Figure 13 The single component shown can be implemented as multiple distributed components. Additionally or alternatively, Figure 13 The set (one or more) components shown are executable and described as being composed of Figure 13 The other set of components shown performs one or more functions.

[0210] The following provides an overview of some aspects of this disclosure: Aspect 1: A method of wireless communication performed by a user equipment (UE), the method comprising: receiving from a network node an indication of a time-domain rotation factor associated with a respective RIS in one or more reconfigurable smart surfaces (RIS); receiving a respective reference signal during a time-domain measurement opportunity via a direct link with the network node and via one or more indirect links associated with the one or more RIS; and sending a report to the network node, the report indicating, in association with a measurement of the respective reference signal, an estimated Doppler frequency of the respective link including the direct link and the one or more indirect links, the estimated Doppler frequency being estimated using the time-domain rotation factor associated with the respective RIS.

[0211] Aspect 2: According to the method of aspect 1, wherein the one or more indirect links are associated with the reflection coefficient of the corresponding RIS application associated with the time-domain rotation factor.

[0212] Aspect 3: The method according to any one of Aspects 1 to 2, wherein the time-domain rotation factor is based on the number of the one or more RIS and the maximum Doppler frequency associated with the direct link and the one or more indirect links.

[0213] Aspect 4: The method according to any one of Aspects 1 to 3, wherein the time-domain rotation factor is based on the number of the one or more RIS, the duration of the time-domain measurement timing, and the index value of the corresponding RIS.

[0214] Aspect 5: The method according to any one of Aspects 1 to 4, wherein the indication of the time-domain rotation factor includes an indication of the value of a corresponding time-domain rotation factor among the time-domain rotation factors.

[0215] Aspect 6: The method according to any one of Aspects 1 to 5, wherein the indication of the time-domain rotation factor includes an indication of the duration of the time-domain measurement timing, the number of the one or more RIS, and the index value of the one or more RIS.

[0216] Aspect 7: The method according to any one of Aspects 1 to 6, wherein the indication of the time-domain rotation factor is included in at least one of radio resource control communication, medium access control (MAC) control element communication, or downlink control information communication.

[0217] Aspect 8: The method according to any one of Aspects 1 to 7, the method further comprising: estimating a channel response associated with the corresponding reference signal and the corresponding link; and estimating, for a RIS among the one or more RIS, a Doppler spectrum associated with the RIS via the channel response and a time-domain rotation factor associated with the RIS among the time-domain rotation factors, wherein the estimated Doppler frequencies associated with the RIS among the estimated Doppler frequencies are based on the Doppler spectrum associated with the RIS.

[0218] Aspect 9: The method according to aspect 8, wherein the Doppler spectrum associated with the RIS is a drifted version of the channel Doppler spectrum associated with the channel response, wherein the drift associated with the Doppler spectrum is based on the time-domain rotation factor associated with the RIS.

[0219] Aspect 10: The method according to any one of Aspects 1 to 9, wherein the one or more indirect links are associated with a corresponding Doppler spectrum that reflects the corresponding reference signal without overlap using the time-domain rotation factor based on the one or more RIS, and wherein the Doppler frequency of the corresponding indirect link in the estimated Doppler frequency is associated with the corresponding Doppler spectrum.

[0220] Aspect 11: The method according to any one of Aspects 1 to 10, wherein the one or more indirect links are associated with a corresponding Doppler spectrum, and wherein the Doppler frequency of the corresponding indirect link in the estimated Doppler frequency is associated with the highest received power within the corresponding Doppler spectrum.

[0221] Aspect 12: The method according to any one of Aspects 1 to 11, wherein the one or more indirect links are associated with a corresponding Doppler spectrum, wherein the Doppler frequency of the indirect link associated with the RIS in the one or more RIS in the estimated Doppler frequency is based on the inverse discrete Fourier transform of a drift version of the Doppler spectrum associated with the indirect link in the corresponding Doppler spectrum, and wherein the drift associated with the drift version of the Doppler spectrum is associated with a time-domain rotation factor associated with the RIS in the time-domain rotation factor.

[0222] Aspect 13: The method according to any one of Aspects 1 to 12, wherein each of the respective reference signals includes a tracking reference signal or a channel state information reference signal.

[0223] Aspect 14: A method of wireless communication performed by a network node, the method comprising: transmitting, for a user equipment (UE) and one or more reconfigurable smart surfaces (RIS), an indication of a time-domain rotation factor associated with a respective RIS of the one or more RIS; transmitting a reference signal during a time-domain measurement opportunity via a direct link with the UE and via one or more indirect links associated with the one or more RIS; and receiving a report associated with the UE, the report indicating, in association with a measurement of the reference signal, an estimated Doppler frequency of the respective link including the direct link and the one or more indirect links, the estimated Doppler frequency being estimated using the time-domain rotation factor associated with the respective RIS.

[0224] Aspect 15: According to the method of aspect 14, wherein the one or more indirect links are associated with the reflection coefficient of the corresponding RIS application associated with the time-domain rotation factor.

[0225] Aspect 16: The method according to any one of Aspects 14 to 15, wherein the time-domain rotation factor is based on the number of the one or more RIS and the maximum Doppler frequency associated with the direct link and the one or more indirect links.

[0226] Aspect 17: According to the method of aspect 16, wherein the maximum Doppler frequency is associated with the permissible speed of the UE.

[0227] Aspect 18: The method according to any one of Aspects 14 to 17, wherein the time-domain rotation factor is based on the number of the one or more RIS, the duration of the time-domain measurement timing, and the index value of the corresponding RIS.

[0228] Aspect 19: The method according to any one of aspects 14 to 18, wherein the indication of the time-domain rotation factor includes an indication of the value of a corresponding time-domain rotation factor among the time-domain rotation factors.

[0229] Aspect 20: The method according to any one of aspects 14 to 19, wherein the indication of the time-domain rotation factor includes an indication of the duration of the time-domain measurement timing, the number of the one or more RIS, and the index value of the one or more RIS.

[0230] Aspect 21: The method according to any one of aspects 14 to 20, wherein the indication of the time-domain rotation factor is included in at least one of radio resource control communication, medium access control (MAC) control element communication, or downlink control information communication.

[0231] Aspect 22: The method according to any one of aspects 14 to 21, wherein the corresponding reference signal includes a tracking reference signal or a channel state information reference signal.

[0232] Aspect 23: A method for wireless communication performed by a reconfigurable smart surface (RIS), the method comprising: receiving from a network node an indication of a time-domain rotation factor associated with the RIS; and using a reflection coefficient to reflect a reference signal associated with the network node, the reflection coefficient being based on the time-domain rotation factor.

[0233] Aspect 24: According to the method of aspect 23, wherein the time-domain rotation factor is based on the number of one or more RIS including the RIS and the maximum Doppler frequency associated with the network node.

[0234] Aspect 25: The method according to any one of Aspects 23 to 24, wherein the time-domain rotation factor is based on the number of one or more RIS including the RIS reflecting the reference signal, the duration of the time-domain measurement timing, and the index value of the RIS.

[0235] Aspect 26: The method according to any one of aspects 23 to 25, wherein the indication of the time-domain rotation factor includes an indication of the value of the time-domain rotation factor.

[0236] Aspect 27: The method according to any one of Aspects 23 to 26, wherein the indication of the time-domain rotation factor includes an indication of the duration of the time-domain measurement timing, the number of one or more RIS reflecting the reference signal, and the index value of the RIS.

[0237] Aspect 28: The method according to any one of Aspects 23 to 27, wherein the indication of the time-domain rotation factor is included in at least one of radio resource control communication, medium access control (MAC) control element communication, or downlink control information communication.

[0238] Aspect 29: The method according to any one of Aspects 23 to 28, wherein the reference signal includes a tracking reference signal or a channel state information reference signal.

[0239] Aspect 30: An apparatus for wireless communication at a device, the apparatus comprising: a processor; a memory coupled to the processor; and instructions stored in the memory and executable by the processor to cause the apparatus to perform the method according to one or more of aspects 1 to 29.

[0240] Aspect 31: A device for wireless communication, the device comprising: a memory; and one or more processors coupled to the memory, the one or more processors being configured to perform the method according to one or more of aspects 1 to 29.

[0241] Aspect 32: An apparatus for wireless communication, the apparatus comprising at least one component for performing the method according to one or more of aspects 1 to 29.

[0242] Aspect 33: A non-transitory computer-readable medium storing code for wireless communication, said code including instructions executable by a processor to perform the methods described in one or more of aspects 1 to 29.

[0243] Aspect 34: A non-transitory computer-readable medium storing a set of instructions for wireless communication, the set of instructions comprising one or more instructions that, when executed by one or more processors of a device, cause the device to perform the method according to one or more of aspects 1 to 29.

[0244] While the foregoing disclosure provides examples and descriptions, it is not intended to be exhaustive or to limit aspects to the precise form disclosed. Modifications and variations can be made based on the foregoing disclosure, or from various aspects of practice.

[0245] As used herein, the term "component" is intended to be interpreted broadly as hardware and / or a combination of hardware and software. Whether referred to as software, firmware, middleware, microcode, hardware description language, or other names, "software" should be interpreted broadly as meaning instructions, instruction sets, code, code segments, program code, programs, subroutines, software modules, applications, software applications, software packages, routines, subroutines, objects, executable files, threads of execution, procedures and / or functions, and other examples. As used herein, a "processor" is implemented in hardware and / or a combination of hardware and software. It will be apparent that the systems and / or methods described herein can be implemented through various forms of hardware and / or combinations of hardware and software. The actual dedicated control hardware or software code used to implement these systems and / or methods is not limiting in any way. Therefore, no specific software code is referred to in this document to describe the operation and behavior of the systems and / or methods, as those skilled in the art will understand that the software and hardware can be designed, at least in part, based on the descriptions herein, to implement the systems and / or methods.

[0246] As used herein, the term "determine" encompasses a wide variety of actions, and therefore, "determine" can include operations, calculations, processing, derivation, investigation, lookup (such as by searching in a table, database, or other data structure), reasoning, probing, and / or measurement, among others. Additionally, "determine" can include receiving (such as receiving information), accessing (such as accessing data stored in memory), and / or sending (such as sending information), among others. Furthermore, "determine" can include parsing, selecting, obtaining, choosing, building, and / or other similar actions.

[0247] As used in this article, depending on the context, "meeting the threshold" can mean a value greater than the threshold, greater than or equal to the threshold, less than the threshold, less than or equal to the threshold, equal to the threshold, not equal to the threshold, etc.

[0248] Although specific combinations of features are set forth in the claims and / or disclosed in the specification, these combinations are not intended to limit the disclosure of various aspects. Many of these features may be combined in ways not specifically set forth in the claims and / or not disclosed in the specification. The disclosure of various aspects includes each dependent claim in combination with each other claim in the set of claims. As used herein, the phrase referring to “at least one of” in the list of entries means any combination of these entries, including a single member. As an example, “at least one of a, b, or c” is intended to cover a, b, c, a+b, a+c, b+c, and a+b+c, as well as any combination with multiple of the same element (e.g., a+a, a+a+a, a+a+b, a+a+c, a+b+b, a+c+c, b+b, b+b+b, b+b+c, c+c, and c+c+c, or any other ordering of a, b, and c).

[0249] No element, action, or instruction used herein should be construed as essential or necessary unless explicitly stated otherwise. Furthermore, as used herein, the articles “a” and “an” are intended to include one or more items and are interchangeable with “one or more.” Furthermore, as used herein, the article “described” is intended to include one or more items mentioned in connection with the article “described” and is interchangeable with “one or more.” Furthermore, as used herein, the terms “group” and “cluster” are intended to include one or more items and are interchangeable with “one or more.” If only one item is desired, the phrase “only one” or similar terminology will be used. Furthermore, as used herein, the terms “having” and the like are intended to be open-ended terms that do not limit the elements they modify (e.g., an element “having” A may also have B). Furthermore, as used herein, “based on” is intended to be interpreted in an inclusive sense unless otherwise explicitly indicated. For example, unless otherwise explicitly indicated, “based on” is interchangeable with “at least partially based on,” “associated with,” or “according to.” Specifically, unless the phrase in the context refers to "based on 'one' only" or an equivalent, it can be based solely on "one" or on a combination of "one" and one or more other factors, conditions, or information, whether it is "based on 'one'" or "at least partially based on 'one'". Furthermore, as used herein, the term "or" is intended to be open-ended when used in a series and can be used interchangeably with "and / or" unless otherwise explicitly stated (e.g., if used in conjunction with "any" or "only one").

Claims

1. A user equipment (UE) for wireless communication, the user equipment (UE) comprising: Memory; and One or more processors, said one or more processors being coupled to the memory and configured to: Receive from network nodes an indication of the time-domain rotation factor associated with a corresponding RIS in one or more reconfigurable smart surfaces (RIS); During time-domain measurement, the corresponding reference signal is received via a direct link to the network node and via one or more indirect links associated with the one or more RIS; as well as A report is sent to the network node, the report indicating, in association with the measurement of the corresponding reference signal, the estimated Doppler frequency of the corresponding link, including the direct link and the one or more indirect links, the estimated Doppler frequency being estimated using the time-domain rotation factor associated with the corresponding RIS.

2. The UE of claim 1, wherein the one or more indirect links are associated with a reflection coefficient of the corresponding RIS application associated with the time-domain rotation factor.

3. The UE of claim 1, wherein the time-domain rotation factor is based on the number of the one or more RIS and the maximum Doppler frequency associated with the direct link and the one or more indirect links.

4. The UE of claim 1, wherein the time-domain rotation factor is based on the number of the one or more RIS, the duration of the time-domain measurement timing, and the index value of the corresponding RIS.

5. The UE of claim 1, wherein the indication of the time-domain rotation factor includes an indication of the value of a corresponding time-domain rotation factor among the time-domain rotation factors.

6. The UE of claim 1, wherein the indication of the time-domain rotation factor includes an indication of the duration of the time-domain measurement timing, the number of the one or more RIS, and the index value of the one or more RIS.

7. The UE of claim 1, wherein the indication of the time-domain rotation factor is included in at least one of radio resource control communication, medium access control (MAC) control element communication, or downlink control information communication.

8. The UE of claim 1, wherein the one or more processors are further configured to: Estimate the channel response associated with the corresponding reference signal and the corresponding link; and For one or more RIS, the Doppler spectrum associated with the RIS is estimated via the channel response and the time-domain rotation factor associated with the RIS in the time-domain rotation factor. The estimated Doppler frequencies associated with the RIS are based on the Doppler spectrum associated with the RIS.

9. The UE of claim 8, wherein the Doppler spectrum associated with the RIS is a drifted version of the channel Doppler spectrum associated with the channel response, wherein the drift associated with the Doppler spectrum is based on the time-domain rotation factor associated with the RIS.

10. A network node for wireless communication, the network node comprising: Memory; and One or more processors, said one or more processors being coupled to the memory and configured to: Send an indication of the time-domain rotation factor associated with the corresponding RIS among the one or more RIS for the user equipment (UE) and one or more reconfigurable smart surfaces (RIS); Reference signals are transmitted during time-domain measurement opportunities via a direct link to the UE and via one or more indirect links associated with the one or more RIS. as well as The system receives a report associated with the UE, the report indicating, in connection with a measurement of the reference signal, an estimated Doppler frequency for a corresponding link including the direct link and one or more indirect links, the estimated Doppler frequency being estimated using the time-domain rotation factor associated with the corresponding RIS.

11. The network node of claim 10, wherein the one or more indirect links are associated with a reflection coefficient of the corresponding RIS application associated with the time-domain rotation factor.

12. The network node of claim 10, wherein the time-domain rotation factor is based on the number of the one or more RIS and the maximum Doppler frequency associated with the direct link and the one or more indirect links.

13. The network node of claim 12, wherein the maximum Doppler frequency is associated with the permissible speed of the UE.

14. The network node of claim 10, wherein the time-domain rotation factor is based on the number of the one or more RIS, the duration of the time-domain measurement timing, and the index value of the corresponding RIS.

15. The network node of claim 10, wherein the indication of the time-domain rotation factor includes an indication of the value of a corresponding time-domain rotation factor among the time-domain rotation factors.

16. A method for wireless communication performed by a user equipment (UE), the method comprising: Receive from network nodes an indication of the time-domain rotation factor associated with a corresponding RIS in one or more reconfigurable smart surfaces (RIS); During time-domain measurement, the corresponding reference signal is received via a direct link to the network node and via one or more indirect links associated with the one or more RIS; as well as A report is sent to the network node, the report indicating, in association with the measurement of the corresponding reference signal, the estimated Doppler frequency of the corresponding link, including the direct link and the one or more indirect links, the estimated Doppler frequency being estimated using the time-domain rotation factor associated with the corresponding RIS.

17. The method of claim 16, wherein the one or more indirect links are associated with the reflection coefficient of the corresponding RIS application associated with the time-domain rotation factor.

18. The method of claim 16, wherein the time-domain rotation factor is based on the number of the one or more RIS and the maximum Doppler frequency associated with the direct link and the one or more indirect links.

19. The method of claim 16, wherein the time-domain rotation factor is based on the number of the one or more RIS, the duration of the time-domain measurement timing, and the index value of the corresponding RIS.

20. The method of claim 16, wherein the indication of the time-domain rotation factor includes an indication of the value of a corresponding time-domain rotation factor among the time-domain rotation factors.

21. The method of claim 16, wherein the indication of the time-domain rotation factor includes an indication of the duration of the time-domain measurement timing, the number of the one or more RIS, and the index value of the one or more RIS.

22. The method of claim 16, further comprising: Estimate the channel response associated with the corresponding reference signal and the corresponding link; as well as For one or more RIS, the Doppler spectrum associated with the RIS is estimated via the channel response and the time-domain rotation factor associated with the RIS in the time-domain rotation factor. The estimated Doppler frequencies associated with the RIS are based on the Doppler spectrum associated with the RIS.

23. The method of claim 22, wherein the Doppler spectrum associated with the RIS is a drifted version of the channel Doppler spectrum associated with the channel response, wherein the drift associated with the Doppler spectrum is based on the time-domain rotation factor associated with the RIS.

24. The method of claim 16, wherein the one or more indirect links are associated with corresponding Doppler spectra that reflect the corresponding reference signal without overlap using the time-domain rotation factor based on the one or more RIS, and The Doppler frequencies of the corresponding indirect links in the estimated Doppler frequencies are associated with the corresponding Doppler spectrum.

25. The method of claim 16, wherein the one or more indirect links are associated with a corresponding Doppler spectrum, and The Doppler frequency of the corresponding indirect link in the estimated Doppler frequency is associated with the highest received power within the corresponding Doppler spectrum.

26. The method of claim 16, wherein the one or more indirect links are associated with a corresponding Doppler spectrum. The estimated Doppler frequencies of the indirect links associated with the RIS in one or more RIS are based on the inverse discrete Fourier transform of a drifted version of the Doppler spectrum associated with the indirect links in the corresponding Doppler spectrum, and The drift associated with the drift version of the Doppler spectrum is associated with the time-domain rotation factor associated with the RIS in the time-domain rotation factor.

27. A method for wireless communication performed by a network node, the method comprising: Send an indication of the time-domain rotation factor associated with the corresponding RIS among the one or more RIS for the user equipment (UE) and one or more reconfigurable smart surfaces (RIS); Reference signals are transmitted during time-domain measurement opportunities via a direct link to the UE and via one or more indirect links associated with the one or more RIS. as well as The system receives a report associated with the UE, the report indicating, in connection with a measurement of the reference signal, an estimated Doppler frequency for a corresponding link including the direct link and one or more indirect links, the estimated Doppler frequency being estimated using the time-domain rotation factor associated with the corresponding RIS.

28. The method of claim 27, wherein the indication of the time-domain rotation factor includes an indication of the value of a corresponding time-domain rotation factor among the time-domain rotation factors.

29. The method of claim 27, wherein the indication of the time-domain rotation factor includes an indication of the duration of the time-domain measurement timing, the number of the one or more RIS, and the index value of the one or more RIS.

30. The method of claim 27, wherein the indication of the time-domain rotation factor is included in at least one of radio resource control communication, medium access control (MAC) control element communication, or downlink control information communication.

Images