Transmitter pre-equalization for power reduction of XR device receivers

Abstract

A method and related apparatus for wireless communication at a user equipment (UE) are provided. In the method, the UE obtains channel information of a sidelink channel between the UE and a receiving device, and performs a pre-equalization process on a signal to be transmitted to the receiving device based on the channel information to obtain a pre-equalized signal. The UE then sends the pre-equalized signal to the receiving device over the sidelink channel.

Description

[0001] Cross-reference to related applications

[0002] This application claims the benefit of U.S. non-provisional patent application No. 18 / 499,915, filed November 1, 2023, entitled “TRANSMITTER PRE-EQUALIZATION FOR POWER REDUCTION OF XR DEVICE RECEIVER”, the entire contents of which are expressly incorporated herein by reference. Technical Field

[0003] This disclosure relates generally to communication systems, and more specifically to equalization for wireless communication with a receiver of an extended reality (XR) device. Background Technology

[0004] 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 may employ multiple access technologies capable of supporting communication with multiple users by sharing available system resources. Examples of such multiple access technologies include Code Division Multiple Access (CDMA) systems, Time Division Multiple Access (TDMA) systems, Frequency Division Multiple Access (FDMA) systems, Orthogonal Frequency Division Multiple Access (OFDMA) systems, Single Carrier Frequency Division Multiple Access (SC-FDMA) systems, and Time Division Synchronous Code Division Multiple Access (TD-SCDMA) systems.

[0005] These multiple access technologies have been adopted in various telecommunications standards to provide a common protocol that enables different wireless devices to communicate at the city, national, regional, and even global levels. An example telecommunications standard is 5G New Radio (NR). 5G NR is part of the Continuous Evolution of Mobile Broadband (CEM) program issued by the 3rd Generation Partnership Project (3GPP) to meet new requirements associated with latency, reliability, security, scalability (e.g., with the Internet of Things (IoT),) and other requirements. 5G NR includes services associated with enhanced mobile broadband (eMBB), massive machine-type communications (mMTC), and ultra-reliable low-latency communications (URLLC). Some aspects of 5G NR can be based on the 4G Long Term Evolution (LTE) standard. Further improvements to 5G NR technology are needed. Furthermore, these improvements can also be applied to other multiple access technologies and telecommunications standards that adopt these technologies. Summary of the Invention

[0006] The following is a simplified summary of one or more aspects to provide a basic understanding of these aspects. This summary is not a comprehensive overview of all conceived aspects. It neither identifies key or essential elements of all aspects nor describes the scope of any or all aspects. Its sole purpose is to present some concepts of one or more aspects in a simplified form as a prelude to the more detailed descriptions that follow.

[0007] In one aspect of this disclosure, methods, computer-readable media, and apparatus for wireless communication at a user equipment (UE) are provided. The apparatus may include at least one memory and at least one processor coupled to the at least one memory. Based at least in part on information stored in the at least one memory, the at least one processor may be configured, individually or in any combination, to: obtain channel information of a sidelink channel between the UE and a receiving device; perform a pre-equalization process on a signal to be transmitted to the receiving device based on the channel information to obtain a pre-equalized signal; and transmit the pre-equalized signal to the receiving device via the sidelink channel.

[0008] In one aspect of this disclosure, a method, computer-readable medium, and apparatus for wireless communication at a receiving device are provided. The apparatus may include at least one memory and at least one processor coupled to the at least one memory. Based at least in part on information stored in the at least one memory, the at least one processor may be configured, individually or in any combination, to: receive a dedicated reference signal from a UE; transmit channel information of a sidelink channel between the UE and the receiving device to the UE based on the dedicated reference signal; receive a pre-equalized signal from the UE; and process the pre-equalized signal using a simplified reception procedure. The simplified reception procedure skips the equalization process for the pre-equalized signal.

[0009] To achieve the foregoing and related objectives, one or more aspects may include the features fully described below and specifically pointed out in the claims. The following description and drawings set forth some exemplary features of one or more aspects in detail. However, these features indicate only a few of the various ways in which the principles of the various aspects may be employed. Attached Figure Description

[0010] Figure 1 This is a diagram illustrating an example of a wireless communication system and an access network.

[0011] Figure 2A This is an illustration of an example of the first frame according to various aspects of this disclosure.

[0012] Figure 2B This is a diagram illustrating examples of downlink (DL) channels within a subframe according to various aspects of this disclosure.

[0013] Figure 2C This is an illustration of an example of a second frame according to various aspects of this disclosure.

[0014] Figure 2D This is a diagram illustrating examples of uplink (UL) channels within a subframe according to various aspects of this disclosure.

[0015] Figure 3 This is a diagram illustrating examples of base stations and user equipment (UEs) in an access network.

[0016] Figure 4 An example of an extended reality (XR) business flow is shown.

[0017] Figure 5 This is a diagram illustrating an example of the split XR method.

[0018] Figure 6 This is a diagram illustrating the physical (PHY) layer receiver (Rx) architecture.

[0019] Figure 7A This is a diagram illustrating an example linear pre-equilibrium scheme on the Tx side according to various aspects of this disclosure.

[0020] Figure 7B This is a diagram illustrating examples of nonlinear pre-equalization schemes on the Tx side according to various aspects of this disclosure.

[0021] Figure 8 This is a block diagram illustrating an example Tx pre-equalization process according to various aspects of this disclosure.

[0022] Figure 9 This is an illustration of example transmission of channel information from an XR device to a UE according to various aspects of this disclosure.

[0023] Figure 10 This is a call flowchart illustrating various aspects of wireless communication methods according to this disclosure.

[0024] Figure 11 This is a flowchart illustrating various methods of wireless communication at a UE according to various aspects of this disclosure.

[0025] Figure 12 This is a flowchart illustrating various methods of wireless communication at a UE according to various aspects of this disclosure.

[0026] Figure 13 This is a flowchart illustrating various methods of wireless communication at a receiving device according to various aspects of this disclosure.

[0027] Figure 14This is a flowchart illustrating various methods of wireless communication at a receiving device according to various aspects of this disclosure.

[0028] Figure 15 These are illustrations illustrating specific hardware implementations used for example devices and / or network entities.

[0029] Figure 16 This is a diagram illustrating an example of a hardware implementation used for an example network entity.

[0030] Figure 17 These are illustrations illustrating example XR service characteristics and examples of processing at XR servers and XR devices according to various aspects of this disclosure.

[0031] Figure 18 This is a diagram illustrating a split XR architecture according to various aspects of this disclosure. Detailed Implementation

[0032] Extended Reality (XR) is emerging as a promising technology for applications such as personal electronics. XR technology faces challenges, including the tension between the computational demands of XR applications and the physical constraints of XR devices, such as weight, power consumption, and head dissipation. XR applications may involve significant processing power to deliver the best user experience, such as high frame rates (e.g., fps). (e.g., 120Hz) and high-quality video formats (e.g., 8K). However, the portability and compactness of XR devices prioritize lower weight, power consumption, and heat dissipation. Balancing such computational power with lower weight, lower power consumption, and reduced heat dissipation can be challenging. In some aspects, a split-XR approach can be used to offload some XR-related processing tasks to the companion device to reduce the processing load on the XR device. However, due to various end-to-end (E2E) considerations (such as photon-to-motion latency requirements and the capacity of the wireless link connecting the XR device and the companion device), a split-XR approach may retain many processing components on the XR device. Therefore, even with a split-XR approach, the power consumption of the XR device may be excessive for video quality / user experience benchmarks. The example aspects presented in this paper provide methods and apparatus for reducing, eliminating, or removing receiver complexity associated with receiver (Rx) equalization, which can be one of the major contributors to modem complexity, by performing a pre-equalization process for the XR device at the user equipment (UE) or companion device.

[0033] Various aspects are involved in wireless communication as a whole. Some aspects are more specifically related to transmitter pre-equalization to achieve power reduction and reduce the complexity of the XR device receiver while maintaining the quality of user experience. In some examples, the UE (e.g., as a companion device to the XR device) first obtains channel information of the sidelink channel between the UE and the receiving device (XR device). Then, based on the channel information, the UE performs a pre-equalization process on the signal to be sent to the receiving device to obtain a pre-equalized signal, and sends the pre-equalized signal to the receiving device through the sidelink channel. In some aspects, the channel information may include Received (Rx) Channel State Information (CSI) associated with the sidelink channel, and in some examples, the channel information may also include channel noise information, which includes the noise covariance matrix associated with the sidelink channel. In some examples, the UE may obtain the channel information directly from the receiving device. In some examples, the UE may obtain the channel information based on a set of received samples received from the receiving device.

[0034] 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 applying a pre-equalization process at the UE (accompanying device) rather than the XR receiving device, the described techniques allow for a reduction in equalization-related complexity at the XR device, thereby allowing for simpler and more portable / wearable hardware designs for the XR device while maintaining the user experience. In some examples, by employing pre-equalization on the transmitter side (e.g., on the accompanying device side or the UE side), the described techniques enable the communication channel between the UE and the XR receiving device to be treated as an additive white Gaussian noise (AWGN) channel and allow the XR device to skip multiple processing steps that would otherwise be performed by the XR device, thereby reducing the computational burden on the XR device. In some examples, by providing multiple pre-equalization options on the transmitter side, the described techniques provide the flexibility to select an appropriate method based on variable conditions.

[0035] The detailed descriptions following, illustrated with reference to the accompanying drawings, describe various configurations and do not represent the only configurations in which the concepts described herein can be practiced. To provide a thorough understanding of the various concepts, the detailed descriptions include specific details. However, these concepts can be practiced without these specific details. In some instances, well-known structures and components are shown in block diagram form to avoid obscuring these concepts.

[0036] Various apparatuses and methods are presented with reference to several aspects of a telecommunications system. These apparatuses and methods are described in detail below and illustrated in the accompanying drawings by various blocks, components, circuits, processes, algorithms, etc. (collectively, “elements”). These elements may be implemented using electronic hardware, computer software, or any combination thereof. Whether these elements are implemented as hardware or software depends on the specific application and the design constraints imposed on the system as a whole.

[0037] As an example, an element, any part of an element, or any combination of elements may be implemented as a "processing system" including one or more processors. When multiple processors are implemented, the multiple processors may perform functions individually or in combination. Examples of processors include microprocessors, microcontrollers, graphics processing units (GPUs), central processing units (CPUs), application processors, digital signal processors (DSPs), reduced instruction set computing (RISC) processors, system-on-a-chip (SoCs), baseband processors, field-programmable gate arrays (FPGAs), programmable logic devices (PLDs), state machines, gate logic, discrete hardware circuits, and other suitable hardware configured to perform the various functionalities described throughout this disclosure. One or more processors in the processing system can execute software. Whether referred to as software, firmware, middleware, microcode, hardware description language, or other terms, software should be broadly interpreted as instructions, instruction sets, code, code segments, program code, programs, subroutines, software components, applications, software applications, software packages, routines, subroutines, objects, executable files, threads of execution, procedures, functions, or any combination thereof.

[0038] Therefore, in one or more example aspects, specific implementations, and / or use cases, the described functionality may be implemented in hardware, software, or any combination thereof. If implemented in software, the functionality may be stored or encoded as one or more instructions or code on a computer-readable medium. Computer-readable media include computer storage media. Storage media may be any available medium accessible to a computer. By way of example, such computer-readable media may include random access memory (RAM), read-only memory (ROM), electrically erasable programmable ROM (EEPROM), optical disc storage devices, magnetic disk storage devices, other magnetic storage devices, combinations of these types of computer-readable media, or any other medium that can be used to store computer-executable code in the form of instructions or data structures accessible to a computer.

[0039] While aspects, implementations, and / or use cases are described herein by way of example, additional or different aspects, implementations, and / or use cases may arise in many different arrangements and scenarios. The aspects, implementations, and / or use cases described herein can be implemented across many different platform types, devices, systems, shapes, sizes, and package arrangements. For example, aspects, implementations, and / or use cases may arise via integrated chip implementations and other devices based on non-modular components (e.g., end-user devices, vehicles, communication devices, computing devices, industrial equipment, retail / purchasing devices, medical devices, AI-enabled devices, etc.). While some examples may or may not be specific to a use case or application, the described examples may exhibit broad applicability. Aspects, implementations, and / or use cases can range from chip-level or modular components to non-modular, non-chip-level implementations, and further to aggregated, distributed, or original equipment manufacturer (OEM) devices or systems incorporating one or more of the technologies described herein. In some practical settings, devices incorporating the described aspects and features may also include additional components and features for implementing and practicing the claimed and described aspects. For example, the transmission and reception of wireless signals necessarily involve multiple components for analog and digital purposes (e.g., hardware components including antennas, RF chains, power amplifiers, modulators, buffers, processors, interleavers, adders / summers, etc.). The techniques described herein can be practiced in a wide variety of devices, chip-level components, systems, distributed arrangements, aggregated or decomposed components, end-user equipment, etc., of various sizes, shapes, and configurations.

[0040] The deployment of communication systems such as 5G NR systems can be arranged in a variety of ways using various components or parts. In a 5G NR system or network, network nodes, network entities, network mobility elements, radio access network (RAN) nodes, core network nodes, network elements or network equipment (such as base stations (BS)), or one or more units (or components) performing base station functionality can be implemented in aggregated or decomposed architectures. For example, BSs (such as Node B (NB), evolved NB (eNB), NR BS, 5G NB, access point (AP), transmit / receive point (TRP), or cell, etc.) can be implemented as aggregated base stations (also known as standalone BS or monolithic BS) or decomposed base stations.

[0041] Aggregated base stations can be configured to utilize a radio protocol stack that is physically or logically integrated within a single RAN node. Decentralized base stations can be configured to utilize a protocol stack that is physically or logically distributed across two or more units, such as one or more central or centralized units (CUs), one or more distributed units (DUs), or one or more radio units (RUs). In some aspects, the CU may be implemented within a RAN node, and one or more DUs may co-located with the CU, or alternatively, may be geographically or virtually distributed across one or more other RAN nodes. DUs may be implemented to communicate with one or more RUs. Each of the CU, DU, and RU may be implemented as a virtual unit, namely a virtual central unit (VCU), a virtual distributed unit (VDU), or a virtual radio unit (VRU).

[0042] Base station operation or network design can take into account the aggregation characteristics of base station functionality. For example, decomposed base stations can be utilized in Integrated Access Backhaul (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)). Decomposition can include distributing functionality across two or more units in various physical locations, as well as virtually distributing the functionality of at least one unit, which enables flexibility in network design. The various units of a decomposed base station or decomposed RAN architecture can be configured to communicate wirelessly with at least one other unit.

[0043] Figure 1 Figure 100 illustrates an example of a wireless communication system and access network. The illustrated wireless communication system includes a decomposed base station architecture. The decomposed base station architecture may include one or more CUs 110, which may communicate directly with the core network 120 via a backhaul link, or indirectly with the core network 120 via one or more decomposed base station units, such as a near real-time (near-RT) RAN Intelligent Controller (RIC) 125 via an E2 link, or a non-real-time (non-RT) RIC 115 associated with a Service Management and Orchestration (SMO) framework 105, or both. CUs 110 may communicate with one or more DUs 130 via a corresponding midhaul link (such as an F1 interface). DUs 130 may communicate with one or more RUs 140 via a corresponding fronthaul link. RUs 140 may communicate with a corresponding UE 104 via one or more radio frequency (RF) access links. In some implementations, a UE 104 may be served simultaneously by multiple RUs 140.

[0044] Each of the units (i.e., CU 110, DU 130, RU 140, and near-RT RIC 125, non-RT RIC 115, and SMO frame 105) 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 of the units, or an associated processor or controller providing instructions to the communication interfaces of these units, may be configured to communicate with one or more other units via transmission media. For example, these units may include wired interfaces configured to receive signals or transmit signals to one or more other units via wired transmission media. Additionally, these units may include wireless interfaces that may include receivers, transmitters, or transceivers (such as RF transceivers) configured to receive signals via wireless transmission media and / or transmit signals to one or more other units.

[0045] In some aspects, the CU 110 can host one or more higher-level control functions. Such control functions may include Radio Resource Control (RRC), Packet Data Convergence Protocol (PDCP), Serving Data Adaptation Protocol (SDAP), etc. Each control function can be implemented using an interface configured to signal to other control functions hosted by the CU 110. The CU 110 can be configured to handle user plane functionality (i.e., Central Unit-User Plane (CU-UP)), control plane functionality (i.e., Central Unit-Control Plane (CU-CP)), or a combination thereof. In some implementations, the CU 110 can be logically divided 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 can communicate bidirectionally with the CU-CP units via an interface such as an E1 interface. The CU 110 can be implemented to communicate with the DU 130 for network control and signaling, as needed.

[0046] DU 130 may correspond to a logical unit that includes one or more base station functions for controlling the operation of one or more RU 140s. In some aspects, DU 130 may at least partially host one or more of the Radio Link Control (RLC) layer, Media Access Control (MAC) layer, and one or more high physical (PHY) layers (such as modules for forward error correction (FEC) encoding and decoding, scrambling, modulation, demodulation, etc.) according to functional splits (such as those defined by 3GPP). In some aspects, DU 130 may also host one or more low PHY layers. Each layer (or module) may be implemented using an interface configured to communicate signals with other layers (and modules) hosted by DU 130 or with control functions hosted by CU 110.

[0047] Lower-layer functionality can be implemented by one or more RU 140s. In some deployments, an RU140 controlled by a DU 130 may correspond to a logical node that at least partially hosts RF processing functions or low-PHY layer functions (such as performing Fast Fourier Transform (FFT), Inverse FFT (iFFT), digital beamforming, Physical Random Access Channel (PRACH) extraction and filtering, etc.) based on functional decomposition such as lower-layer functional decomposition, or both. In this architecture, the RU 140 can be implemented to handle over-the-air (OTA) communications with one or more UEs 104. In some specific implementations, the real-time and non-real-time aspects of control plane and user plane communications with the RU 140 may be controlled by the corresponding DU 130. In some scenarios, this configuration allows the DU 130 and CU 110 to be implemented in cloud-based RAN architectures such as vRAN architectures.

[0048] SMO framework 105 can be configured to support RAN deployment and provisioning of both non-virtualized and virtualized network elements. For non-virtualized network elements, SMO framework 105 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, SMO framework 105 can be configured to interact with a cloud computing platform such as Open Cloud (O-Cloud) 190 to perform network element lifecycle management (such as instantiating virtualized network elements) via a cloud computing platform interface such as the O2 interface. Such virtualized network elements may include, but are not limited to, CU 110, DU 130, RU 140, and near-RT RIC 125. In some implementations, SMO framework 105 can communicate with hardware aspects of the 4G RAN, such as Open eNB (O-eNB) 111, via the O1 interface. Additionally, in some implementations, SMO framework 105 can communicate directly with one or more RU 140s via the O1 interface. SMO framework 105 may also include a non-RT RIC 115 configured to support the functionality of SMO framework 105.

[0049] The non-RT RIC 115 can be configured to include logical functions enabling non-real-time control and optimization of RAN elements and resources, including artificial intelligence (AI) / machine learning (ML) workflows for model training and updates, or policy-based guidance for applications / features in the near-RT RIC 125. The non-RT RIC 115 can be coupled to or communicate with the near-RT RIC 125, such as via an A1 interface. The near-RT RIC 125 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 110s, one or more DU 130s, or both, and O-eNBs to the near-RT RIC 125.

[0050] In some implementations, to generate AI / ML models to be deployed in the near-RT RIC 125, the non-RT RIC 115 may receive parameters or external enrichment information from an external server. This information can be utilized by the near-RT RIC 125 and may be received from non-network data sources or network functions at the SMO framework 105 or the non-RT RIC 115. In some examples, the non-RT RIC 115 or the near-RT RIC 125 may be configured to tune RAN behavior or performance. For example, the non-RT RIC 115 may monitor long-term trends and patterns in performance and employ AI / ML models to perform corrective actions via the SMO framework 105 (such as reconfiguration via O1) or by creating RAN management policies (such as A1 policies).

[0051] At least one of CU 110, DU 130, and RU 140 may be referred to as base station 102. Therefore, base station 102 may include one or more of CU 110, DU 130, and RU 140 (each component is indicated by a dashed line to indicate that each component may or may not be included in base station 102). Base station 102 provides UE 104 with an access point to core network 120. Base station 102 may include macro cells (high-power cellular base stations) and / or small cells (low-power cellular base stations). Small cells include femtocells, picocells, and microcells. A network that includes both small cells and macro cells may be referred to as a heterogeneous network. A heterogeneous network may also include an evolved home node B (eNB) (HeNB), which can provide service to a restricted group referred to as a closed subscriber group (CSG). The communication link between RU 140 and UE 104 may include uplink (UL) transmission (also known as reverse link) from UE 104 to RU 140 and / or downlink (DL) transmission (also known as forward link) transmission from RU 140 to UE 104. The communication link may utilize multiple-input multiple-output (MIMO) antenna techniques, including spatial multiplexing, beamforming, and / or transmit diversity. The communication link may use one or more carriers. For each direction, the total number of carriers used for transmission can be up to [number missing]. Yx MHz ( x For each carrier allocated in carrier aggregation (of component carriers), base station 102 / UE 104 can use up to [number] carriers. Y A spectrum with a bandwidth of MHz (e.g., 5MHz, 10MHz, 15MHz, 20MHz, 100MHz, 400MHz, etc.). Carriers may be adjacent to each other or may not be adjacent to each other. Carrier allocation may be asymmetric with respect to DL and UL (e.g., more or fewer carriers may be allocated to DL compared to UL). Component carriers may include primary component carriers and one or more secondary component carriers. The primary component carrier may be referred to as the primary cell (PCell) and the secondary component carrier may be referred to as the secondary cell (SCell).

[0052] Some UEs 104 can communicate with each other using device-to-device (D2D) communication link 158. D2D communication link 158 can use DL / UL wireless wide area network (WWAN) spectrum. D2D communication link 158 can use one or more sidelink channels, such as Physical Sidelink Broadcast Channel (PSBCH), Physical Sidelink Discovery Channel (PSDCH), Physical Sidelink Shared Channel (PSSCH), and Physical Sidelink Control Channel (PSCCH). D2D communication can be achieved through various wireless D2D communication systems, such as Bluetooth. ™ (Bluetooth is a trademark of the Bluetooth Special Interest Group (SIG), and is based on the IEEE 802.11 standard for Wi-Fi.)™ (Wi-Fi is a trademark of the Wi-Fi Alliance, LTE or NR)

[0053] The wireless communication system may also include a Wi-Fi AP 150, which communicates with the UE 104 (also referred to as a Wi-Fi station (STA)) via a communication link 154, for example, in an unlicensed spectrum such as 5 GHz. When communicating in unlicensed spectrum, the UE 104 / AP 150 may perform a free channel assessment (CCA) to determine whether the channel is available before communication.

[0054] The electromagnetic spectrum is typically subdivided into various categories, bands, channels, etc., based on frequency / wavelength. In 5G NR, two initial operating bands have been designated as frequency ranges FR1 (410MHz to 7.125GHz) and FR2 (24.25GHz to 52.6GHz). Although a portion of FR1 is greater than 6GHz, in various documents and articles, FR1 is often (interchangeably) referred to as the "sub-6GHz" band. Similar naming issues sometimes occur with FR2, which is often (interchangeably) referred to as the "millimeter wave" band in documents and articles, although this is distinct from the Extremely High Frequency (EHF) band (30GHz to 300GHz) designated as "millimeter wave" by the International Telecommunication Union (ITU).

[0055] 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, thus effectively extending 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 bands have been identified as the frequency range designations FR2-2 (52.6 GHz to 71 GHz), FR4 (71 GHz to 114.25 GHz), and FR5 (114.25 GHz to 300 GHz). Each of these higher frequency bands falls within the EHF band.

[0056] In view of the above, unless otherwise specifically stated, the term "below 6 GHz" as used herein can broadly refer to frequencies less than 6 GHz, within FR1, or including intermediate frequency band frequencies. Furthermore, unless otherwise specifically stated, the term "millimeter wave" as used herein can broadly refer to frequencies that can include intermediate frequency band frequencies, within FR2, FR4, FR2-2 and / or FR5, or within the EHF band.

[0057] Base station 102 and UE 104 may each include multiple antennas (such as antenna elements, antenna panels, and / or antenna arrays) to facilitate beamforming. Base station 102 may transmit beamformed signals 182 to UE 104 in one or more transmit directions. UE 104 may receive beamformed signals from base station 102 in one or more receive directions. UE 104 may also transmit beamformed signals 184 to base station 102 in one or more transmit directions. Base station 102 may receive beamformed signals from UE 104 in one or more receive directions. Base station 102 / UE 104 may perform beamforming training to determine the optimal receive and transmit directions for each of base station 102 / UE 104. The transmit and receive directions of base station 102 may be the same or different. The transmit and receive directions of UE 104 may be the same or different.

[0058] Base station 102 may include and / or be referred to as gNB, Node B, eNB, access point, transceiver base station, radio base station, radio transceiver, transceiver function, basic service set (BSS), extended service set (ESS), TRP, network node, network entity, network equipment, or some other suitable terminology. Base station 102 may be implemented as an integrated access and backhaul (IAB) node, relay node, sidelink node, aggregated (monolithic) base station with baseband units (BBU) (including CU and DU) and RU, or may be implemented as a decomposed base station including one or more of CU, DU, and / or RU. A collection of base stations that may include decomposed base stations and / or aggregated base stations may be referred to as Next Generation (NG) RAN (NG-RAN).

[0059] The core network 120 may include Access and Mobility Management Function (AMF) 161, Session Management Function (SMF) 162, User Plane Function (UPF) 163, Unified Data Management (UDM) 164, one or more location servers 168, and other functional entities. AMF 161 is the control node that handles signaling between UE 104 and the core network 120. AMF 161 supports registration management, connection management, mobility management, and other functions. SMF 162 supports session management and other functions. UPF 163 supports packet routing, packet forwarding, and other functions. UDM 164 supports authentication and key agreement (AKA) credential generation, user identity processing, access authorization, and subscription management. One or more location servers 168 are exemplified as including a Gateway Mobile Location Center (GMLC) 165 and a Location Management Function (LMF) 166. However, generally, one or more location servers 168 may include one or more location / positioning servers, which may include one or more of GMLC 165, LMF 166, Position Determination Entity (PDE), Serving Mobile Location Center (SMLC), Mobile Location Center (MPC), etc. GMLC 165 and LMF 166 support UE location services. GMLC 165 provides an interface for clients / applications (e.g., emergency services) to access UE location information. LMF 166 receives measurement and auxiliary information from NG-RAN and UE 104 via AMF 161 to calculate the location of UE 104. NG-RAN may use one or more positioning methods to determine the location of UE 104. Positioning UE 104 may involve signal measurement, location estimation, and optional speed calculation based on these measurements. Signal measurement may be performed by UE 104 and / or base station 102 serving UE 104. The measured signals may be based on one or more of the following systems / signals / sensors: Satellite Positioning System (SPS) 170 (e.g., one or more of Global Navigation Satellite System (GNSS), Global Positioning System (GPS), Non-Terrestrial Network (NTN) or other position / location systems), LTE signals, Wireless Local Area Network (WLAN) signals, Bluetooth signals, Terrestrial Beacon System (TBS), sensor-based information (e.g., barometric pressure sensor, motion sensor), NR Enhanced Cell ID (NR E-CID) method, NR signals (e.g., multiple round-trip time (multiple RTT), DL departure angle (DL-AoD), DL time difference of arrival (DL-TDOA), UL time difference of arrival (UL-TDOA), and UL angle of arrival (UL-AoA) positioning) and / or other systems / signals / sensors.

[0060] Examples of UE 104 include cellular phones, smartphones, Session Initiation Protocol (SIP) phones, laptops, personal digital assistants (PDAs), satellite radios, GPS devices, multimedia devices, video devices, digital audio players (e.g., MP3 players), cameras, game consoles, tablet devices, smart devices, wearable devices, vehicles, electricity meters, air pumps, large or small kitchen appliances, healthcare devices, implants, sensors / actuators, displays, or any other similarly functional device. Some UEs in UE 104 may be referred to as IoT devices (e.g., parking meters, air pumps, toasters, vehicles, heart monitors, etc.). UE 104 may also be referred to as a station, mobile station, subscriber station, mobile unit, subscriber unit, wireless unit, remote unit, mobile device, wireless device, wireless communication device, remote device, mobile subscriber station, access terminal, mobile terminal, wireless terminal, remote terminal, mobile phone, user agent, mobile client, client, or some other suitable terminology. In some scenarios, the term UE may also be applied to one or more companion devices, such as in a device constellation arrangement. One or more of these devices may access the network together and / or individually.

[0061] Refer again Figure 1 In some respects, UE 104 may support operation as an accessory device to one or more XR devices 107. UE 104 may include a transmitter pre-equalization component 198. The transmitter pre-equalization component 198 may be configured to: obtain channel information of a sidelink channel between the UE and a receiving device (e.g., 107); perform a pre-equalization process on the signal to be transmitted to the receiving device based on the channel information to obtain a pre-equalized signal; and transmit the pre-equalized signal to the receiving device through the sidelink channel. While the following description may focus on 5G NR, the concepts described herein may be applicable to other similar domains, such as LTE, LTE-A, CDMA, GSM, and other wireless technologies.

[0062] Figure 2A Figure 200 illustrates an example of the first subframe within a 5G NR frame structure. Figure 2B Figure 230 illustrates an example of a DL channel within a 5G NR subframe. Figure 2C Figure 250 is an example of a second subframe within a 5G NR frame structure. Figure 2DFigure 280 illustrates an example of a UL channel within a 5G NR subframe. The 5G NR frame structure can be Frequency Division Duplex (FDD) (where subframes within a specific set of subcarriers (carrier system bandwidth) are dedicated to either DL or UL) or Time Division Duplex (TDD) (where subframes within a specific set of subcarriers (carrier system bandwidth) are dedicated to both DL and UL). Figure 2A , Figure 2C In the provided example, the 5G NR frame structure is assumed to be TDD, where subframe 4 is configured using slot format 28 (most of which are DL), where D is DL, U is UL, and F is flexible and can be used between DL / UL, and subframe 3 is configured using slot format 1 (all of which are UL). Although subframes 3 and 4 are shown as having slot formats 1 and 28 respectively, any particular subframe can be configured using any of the various available slot formats 0-61. Slot formats 0 and 1 are both DL and UL, respectively. Other slot formats 2-61 include a mixture of DL, UL, and flexible symbols. The UE is configured using the slot format via the received Slot Format Indicator (SFI) (dynamically configured via DL Control Information (DCI) or semi-statically / statically configured via Radio Resource Control (RRC) signaling). Note that the following description also applies to the 5G NR frame structure as TDD.

[0063] Figures 2A to 2D The frame structure is illustrated, and aspects of this disclosure are applicable to other wireless communication technologies that may have different frame structures and / or different channels. A frame (10 ms) can be divided into 10 equal-sized subframes (1 ms). Each subframe may include one or more time slots. Subframes may also include micro-time slots, which may include 7, 4, or 2 symbols. Each time slot may include 14 or 12 symbols, depending on whether the cyclic prefix (CP) is normal or extended. For normal CP, each time slot may include 14 symbols, and for extended CP, each time slot may include 12 symbols. Symbols on the DL may be CP Orthogonal Frequency Division Multiplexing (OFDM) (CP-OFDM) symbols. Symbols on the UL may be CP-OFDM symbols (for high-throughput scenarios) or Discrete Fourier Transform (DFT) Extended OFDM (DFT-s-OFDM) symbols (for power-constrained scenarios; limited to single-stream transmission). The number of time slots within a subframe is based on the CP and a parameter set. The parameter set defines the subcarrier spacing (SCS) (see Table 1). Symbol length / duration can be scaled by 1 / SCS.

[0064]

[0065] Table 1: Parameter Set, SCS, and CP

[0066] For a normal CP (14 symbols / slot), different parameter sets µ 0 through 4 allow 1, 2, 4, 8, and 16 slots per subframe, respectively. For an extended CP, parameter set 2 allows 4 slots per subframe. Therefore, for a normal CP and parameter set µ, there are 14 symbols / slot and 2... µ One time slot / subframe. Subcarrier spacing can be equal to ,in The parameter sets are 0 to 4. Therefore, the subcarrier spacing is 15 kHz for parameter set µ=0 and 240 kHz for parameter set µ=4. The symbol length / duration is negatively correlated with the subcarrier spacing. Figures 2A to 2D Examples of a normal frequency division multiplexing (CP) with 14 symbols per time slot and a parameter set of µ=2 with 4 time slots per subframe are provided. The time slot duration is 0.25 ms, the subcarrier spacing is 60 kHz, and the symbol duration is approximately 16.67 μs. Within the frame set, there may be one or more distinct bandwidth portions (BWPs) of frequency division multiplexing (see [link to relevant documentation]). Figure 2B Each BWP can have a specific set of parameters and CP (normal or extended).

[0067] A resource grid can be used to represent the frame structure. Each time slot consists of a resource block (RB) extending for 12 consecutive subcarriers (also known as a physical RB (PRB)). The resource grid is divided into multiple resource elements (REs). The number of bits carried by each RE depends on the modulation scheme.

[0068] like Figure 2A As illustrated, some of the REs carry reference (pilot) signals (RS) for the UE. RS may include demodulation RS (DM-RS) (indicated as R for a particular configuration, but other DM-RS configurations are possible) and channel state information reference signals (CSI-RS) for channel estimation at the UE. RS may also include beam measurement RS (BRS), beam refinement RS (BRRS), and phase tracking RS (PT-RS).

[0069] Figure 2BExamples of various DL channels within a subframe of a frame are illustrated. The Physical Downlink Control Channel (PDCCH) carries the DCI within one or more Control Channel Elements (CCEs) (e.g., 1, 2, 4, 8, or 16 CCEs), each CCE comprising six RE Groups (REGs), each REG comprising 12 consecutive REs in the OFDM symbol of the RB. A PDCCH within a BWP can be referred to as a Control Resource Set (CORESET). The UE is configured to monitor PDCCH candidates in the PDCCH search space (e.g., the common search space, the UE-specific search space) during PDCCH monitoring timing on the CORESET, where the PDCCH candidates have different DCI formats and different aggregation levels. Additional BWPs may be located at higher and / or lower frequencies on the channel bandwidth. The Primary Synchronization Signal (PSS) may be located within symbol 2 of a specific subframe of the frame. The PSS is used by the UE 104 to determine subframe / symbol timing and physical layer identification. The Secondary Synchronization Signal (SSS) may be located within symbol 4 of a specific subframe of the frame. The SSS is used by the UE to determine the Physical Layer Cell Identifier Group Number and radio frame timing. Based on the Physical Layer Identifier and the Physical Layer Cell Identifier Group Number, the UE can determine the Physical Cell Identifier (PCI). Based on the PCI, the UE can determine the location of the DM-RS. The Physical Broadcast Channel (PBCH), carrying the Master Information Block (MIB), can be logically grouped with the PSS and SSS to form a Synchronization Signal (SS) / PBCH block (also known as an SS block (SSB)). The MIB provides the System Frame Number (SFN) and the number of Restricted Blocks (RBs) in the system bandwidth. The Physical Downlink Shared Channel (PDSCH) carries user data, broadcast system information not transmitted via the PBCH (such as System Information Blocks (SIBs)), and paging messages.

[0070] like Figure 2C As illustrated, some REs in the REs carry DM-RS (indicated as R for one particular configuration, but other DM-RS configurations are possible) for channel estimation at the base station. The UE can transmit DM-RS for the Physical Uplink Control Channel (PUCCH) and DM-RS for the Physical Uplink Shared Channel (PUSCH). The PUSCH DM-RS can be transmitted in the first or first two symbols of the PUSCH. Depending on whether a short or long PUCCH is transmitted and depending on the specific PUCCH format used, the PUCCH DM-RS can be transmitted in different configurations. The UE can transmit a Sounding Reference Signal (SRS). The SRS can be transmitted in the last symbol of a subframe. The SRS can have a comb structure, and the UE can transmit the SRS on one of the comb teeth. The SRS can be used by the base station for channel quality estimation to enable frequency-dependent scheduling of the UL.

[0071] Figure 2DExamples of various UL channels within a subframe of a frame are illustrated. The PUCCH may be located as indicated in one configuration. The PUCCH carries uplink control information (UCI), such as scheduling requests, channel quality indicators (CQI), pre-decoding matrix indicators (PMI), rank indicators (RI), and hybrid automatic repeat request (HARQ) acknowledgment (ACK) (HARQ-ACK) feedback (i.e., one or more HARQ ACK bits indicating one or more ACKs and / or negative ACKs (NACKs)). The PUCCH carries data and may additionally be used to carry buffer status reports (BSR), power clearance reports (PHR), and / or UCIs.

[0072] Figure 3 This is a block diagram illustrating communication between base station 310 and UE 350 in the access network. In the DL, Internet Protocol (IP) packets can be provided to controller / processor 375. Controller / processor 375 implements Layer 3 and Layer 2 functionality. Layer 3 includes the Radio Resource Control (RRC) layer, and Layer 2 includes the Service Data Adaptation Protocol (SDAP) layer, Packet Data Convergence Protocol (PDCP) layer, Radio Link Control (RLC) layer, and Media Access Control (MAC) layer. The controller / processor 375 provides RRC layer functionality associated with broadcasting system information (e.g., MIB, SIB), RRC connection control (e.g., RRC connection paging, RRC connection establishment, RRC connection modification, and RRC connection release), inter-Radio Access Technology (RAT) mobility, and measurement configuration for UE measurement reporting; PDCP layer functionality associated with header compression / decompression, security (encryption, decryption, integrity protection, integrity verification), and handover support functions; RLC layer functionality associated with the delivery of upper-layer packet data units (PDUs), error correction via ARQ, concatenation, segmentation, and reassembly of RLC service data units (SDUs), resegmentation of RLC data PDUs, and reordering of RLC data PDUs; and MAC layer functionality associated with mapping between logical channels and transport channels, multiplexing of MAC SDUs onto transport blocks (TBs), demultiplexing of MAC SDUs from TBs, scheduling information reporting, error correction via HARQ, priority handling, and logical channel priority ordering.

[0073] Transmit (TX) processor 316 and receive (RX) processor 370 implement Layer 1 functionality associated with various signal processing functions. Layer 1 (which includes the physical (PHY) layer) may include error detection on the transport channel, forward error correction (FEC) decoding / decoding of the transport channel, interleaving, rate matching, mapping to the physical channel, modulation / demodulation of the physical channel, and MIMO antenna processing. TX processor 316 processes the mapping to the signal constellation based on various modulation schemes (e.g., binary phase shift keying (BPSK), quadrature phase shift keying (QPSK), M-order phase shift keying (M-PSK), M-order quadrature amplitude modulation (M-QAM)). The decoded and modulated symbols can then be split into parallel streams. Each stream can then be mapped to OFDM subcarriers, multiplexed with a reference signal (e.g., a pilot) in the time and / or frequency domains, and subsequently combined using inverse fast Fourier transform (IFFT) to produce a physical channel carrying a stream of time-domain OFDM symbols. The OFDM stream is spatially pre-decoded to generate multiple spatial streams. Channel estimates from channel estimator 374 can be used to determine the decoding and modulation scheme, as well as for spatial processing. Channel estimates can be derived from reference signals transmitted by UE 350 and / or channel condition feedback. Each spatial stream can then be provided to different antennas 320 via a separate transmitter 318Tx. Each transmitter 318Tx can use the corresponding spatial stream to modulate a radio frequency (RF) carrier for transmission.

[0074] At UE 350, each receiver 354Rx receives signals via its corresponding antenna 352. Each receiver 354Rx recovers the information modulated onto the RF carrier and provides that information to the receive (RX) processor 356. The TX processor 368 and RX processor 356 implement Layer 1 functionality associated with various signal processing functions. The RX processor 356 can perform spatial processing on the information to recover any spatial stream destined for UE 350. If multiple spatial streams are destined for UE 350, the RX processor 356 can combine them into a single OFDM symbol stream. The RX processor 356 then uses a Fast Fourier Transform (FFT) to transform the OFDM symbol stream from the time domain to the frequency domain. The frequency domain signal consists of a separate OFDM symbol stream for each subcarrier of the OFDM signal. The symbols on each subcarrier, along with the reference signal, are recovered and demodulated by determining the most probable signal constellation point transmitted by base station 310. These soft decisions can be based on a channel estimate calculated by channel estimator 358. Subsequently, the soft decision is decoded and deinterleaved to recover the data and control signals originally transmitted by base station 310 on the physical channel. The data and control signals are then provided to controller / processor 359, which implements layer 3 and layer 2 functionality.

[0075] The controller / processor 359 may be associated with at least one memory 360 storing program code and data. The at least one memory 360 may be referred to as a computer-readable medium. In the UL, the controller / processor 359 provides demultiplexing, packet reassembly, decryption, header decompression, and control signal processing between transport and logical channels to recover IP packets. The controller / processor 359 is also responsible for error detection using ACK and / or NACK protocols to support HARQ operation.

[0076] Similar to the functionality described in conjunction with DL transmission performed by base station 310, controller / processor 359 provides RRC layer functionality associated with system information (e.g., MIB, SIB) acquisition, RRC connectivity, and measurement reporting; PDCP layer functionality associated with header compression / decompression and security (encryption, decryption, integrity protection, integrity verification); RLC layer functionality associated with upper-layer PDU delivery, error correction via ARQ, concatenation, segmentation, and reassembly of RLC SDUs, resegmentation of RLC data PDUs, and reordering of RLC data PDUs; and MAC layer functionality associated with mapping between logical channels and transport channels, multiplexing of MAC SDUs onto TBs, demultiplexing of MAC SDUs from TBs, scheduling information reporting, error correction via HARQ, priority handling, and logical channel priority ordering.

[0077] The TX processor 368 can use the channel estimate derived from the reference signal or feedback transmitted by the channel estimator 358 from the base station 310 to select an appropriate decoding and modulation scheme and facilitate spatial processing. The spatial stream generated by the TX processor 368 can be provided to different antennas 352 via individual transmitters 354Tx. Each transmitter 354Tx can use the corresponding spatial stream to modulate an RF carrier for transmission.

[0078] UL transmission is processed at base station 310 in a manner similar to that described in conjunction with the receiver function at UE 350. Each receiver 318Rx receives signals via its corresponding antenna 320. Each receiver 318Rx recovers the information modulated onto the RF carrier and provides that information to RX processor 370.

[0079] The controller / processor 375 may be associated with at least one memory 376 storing program code and data. The at least one memory 376 may be referred to as a computer-readable medium. In the UL, the controller / processor 375 provides demultiplexing, packet reassembly, decryption, header decompression, and control signal processing to recover IP packets between transport and logical channels. The controller / processor 375 is also responsible for error detection using ACK and / or NACK protocols to support HARQ operation.

[0080] At least one of the TX processor 368, RX processor 356, and controller / processor 359 can be configured to combine Figure 1 The transmitter pre-equalization component 198 performs various aspects to, for example, equalize the transmissions to one or more receiving devices (e.g., 107).

[0081] The example aspects presented herein propose techniques for reducing processing at the receiving device (e.g., the receiving device may be referred to as an Rx UE, XR device, etc.) by delegating processing at the receiving device to an adjoining device (e.g., a UE for communication exchange between the auxiliary network and the receiving device), thereby enabling power savings at the receiving device. The aspects presented herein include performing pre-equalization at the adjoining Tx device to reduce receiver complexity at the Rx device.

[0082] XR services can refer to wireless communications used in technologies such as Virtual Reality (VR), Mixed Reality (MR), and / or Augmented Reality (AR). VR can refer to a technology that immerses a user in a simulated experience similar to or different from the real world. Users can interact with a VR system through VR headsets or multi-projection environments that generate realistic images, sounds, and other sensations simulating the user's physical presence in the virtual environment. MR can refer to a technology that blends aspects of virtual and real environments. AR can refer to a technology that uses computer-generated perceptual information to enhance objects residing in the real world (sometimes across multiple sensory modalities such as vision, hearing, touch, somatosensory, and / or olfaction). An AR system can combine real and virtual worlds, real-time interaction, and accurate 3D registration of virtual and real objects. In an example, an AR system can overlay sensory information (e.g., images) onto a natural environment and / or mask real objects from within a natural environment. XR services can include video and / or audio data. XR services can be transmitted by a base station and received by a UE, or XR services can be transmitted by a UE and received by a base station.

[0083] XR services can arrive in periodic service bursts (“XR service bursts”). XR service bursts can vary in terms of the number of packets in each burst and / or the size of each packet in a burst. Figure 4Figure 400 illustrates a first XR stream 402 including a first XR service burst 404 and a second XR service burst 406. As illustrated in Figure 400, the service bursts may include different numbers of packets; for example, the first XR service burst 404 is shown as having three packets (represented as rectangles in Figure 400), and the second XR service burst 406 is shown as having two packets. Furthermore, as illustrated in Figure 400, the three packets in the first XR service burst 404 and the two packets in the second XR service burst 406 may differ in size; that is, the packets within the first XR service burst 404 and the second XR service burst 406 may include different amounts of data.

[0084] XR bursts can arrive in non-integer periods (i.e., within non-integer cycles). The period can differ from an integer number of symbols, time slots, etc. In the example, for 60 frames per second (FPS) video data, an XR burst can arrive in a period of 1 / 60 = 16.67 ms. In another example, for 120 FPS video data, an XR burst can arrive in a period of 1 / 120 = 8.33 ms.

[0085] The arrival time of XR services can vary. For example, an XR service burst may arrive earlier or later than the time the UE (or base station) expects the XR service burst to arrive and be available for transmission. The variability of packet arrival relative to the period (e.g., 16.76ms period, 8.33ms period, etc.) can be referred to as "jitter". In the example, the XR service jitter can range from -4ms (arriving earlier than expected) to +4ms (arriving later than expected). For example, referring to the first XR stream 402, the UE can expect the first packet of the first XR service burst 404 to arrive at time t0, but the first packet of the first XR service burst 404 arrives at time t1.

[0086] XR services may include multiple streams arriving at the UE (or base station) concurrently with each other (or within a threshold time period). For example, Figure 400 includes a second XR stream 408. The second XR stream 408 may have different characteristics from the first XR stream 402. For example, the second XR stream 408 may have XR service bursts with different numbers of packets, different packet sizes, etc. In one example, the first XR stream 402 may include video data, and the second XR stream 408 may include audio data for the video data. In another example, the first XR stream 402 may include internally decoded picture frames (I-frames) containing the complete image, and the second XR stream 408 may include predicted picture frames (P-frames) containing changes from previous images.

[0087] XR is emerging as a promising technology for applications such as personal electronics. XR technology faces challenges, including the tension between the computational demands of XR applications and the physical constraints of XR devices, such as weight, power consumption, and head dissipation. One challenge is creating devices that are lightweight enough for extended mobile use. For example, XR devices could weigh as little as conventional glasses, typically weighing around 30 to 40 grams. Achieving this weight necessitates incorporating lightweight batteries. Another challenge is balancing processing complexity and power consumption. XR devices (such as glasses or goggles) have a smaller surface area compared to other user interfaces (UEs), reducing their heat dissipation capabilities. For wearable XR goggles, this can translate into power consumption limits of only a few watts.

[0088] Figure 17 Figure 1700 is an example illustration of XR service characteristics and their processing at the XR server and XR device. (See Figure 1700.) Figure 17 As shown, Figure 1700 includes a first XR service flow 1710 corresponding to downlink video from base station 1702 to UE 1704. Packets of the first XR service flow 1710 may be associated with periodic nominal time of arrival, may be associated with jitter, may have random packet sizes, and / or may be associated with packet delay limits (PDB). Figure 1700 also includes a second XR service flow 1720 and a third XR service flow 1730, which correspond to uplink traffic from UE 1704 to base station 1702. Figure 17 In the example provided, the second XR traffic flow 1720 corresponds to gesture information and can be associated with the frequency of the small packets. Figure 17 The third XR service flow 1730 corresponds to video or audio data and may be associated with heavy uplink traffic (e.g., larger packets).

[0089] These constraints pose challenges to XR devices, especially when considering the intensive processing required for many XR applications. Standalone XR products offer the flexibility required for “mobility” and can be adapted to specific, static, short-term use scenarios, assuming use in head-mounted displays (HMDs) with higher form factor.

[0090] High form factor HMDs may be inconvenient for some applications. The aspects presented in this paper enable at least a portion of XR processing to be offloaded to a separate companion device. A split-feature XR approach can alleviate some of the burden on the XR device. This approach offloads rendering-related processing to the companion device. However, due to various end-to-end (E2E) considerations, including photon-to-motion latency requirements and the capacity of the wireless link between the XR and the companion device, some processing components may remain on the XR device. Even for applications with lower video quality or user experience benchmarks and less demanding requirements, power consumption on the XR device can remain high.

[0091] Figure 18 This is an example of a split XR architecture as presented in this article, illustrated in Figure 1800. Figure 18 In the illustrated example, Figure 1800 includes an XR device 1802 and an XR server 1804. Figure 18 In the illustrated example, user gesture information and input information are sent by XR device 1802 and received by XR server 1804. XR server 1804 can then send rendered video frames, which are received by XR device 1802 for display. The rate at which user gesture information and controller input are sent can be synchronized with the video frame rate (such as 90Hz). The same applies. XR server 1804 can render video frames based on the latest (or most recent) user pose information available to XR server 1804. To provide a good user experience, the latency from user motion (e.g., at XR device 1802) to server rendering (e.g., at XR server 1804) to device display (e.g., at XR device 1802) can be minimized. This latency can also be referred to as the user motion to server rendering to device display (photon) (M2R2P) latency. In some aspects, the M2R2P latency can vary based on RTT and multimedia processing time at the client (e.g., XR device 1802) and server (e.g., XR server 1804). Additionally, RTT can be based on uplink latency and downlink latency.

[0092] The various aspects presented further address the inherent technical limitations of XR, while improving support for more demanding advanced applications, such as those with fps ≥ 120Hz and video formats ≥ 8k.

[0093] Split-based XR approaches can assume long-distance communication links on licensed spectrum and tight scheduling and interleaving among different served XR users. To manage the capacity allocated to each user, XR devices can locally employ some sensor processing to reduce uplink (UL) data volume (e.g., for 6DoF tracking and eye tracking for field-of-view derivation). Additional sensor or camera data from the XR (on the uplink) and video rendered for the XR device (on the downlink) can be compressed at high compression rates to fit the link capacity per user. Preprocessing of sensor data on the XR device and video compression with high compression rates (e.g., high profile H.264) can be computationally intensive, especially on the encoder side, and both the transmit (Tx) and receive (Rx) paths for video processing require significant double data rate (DDR) usage, a heavy power consumption item. Additionally, due to photon-to-motion latency requirements and the latency associated with the base station-based split-processing, Rx-side processing on XR devices can include asynchronous time warp (ATW) to ensure that the latest moment image is aligned with the most recent pose information. Therefore, the power consumption figures for a split-processing XR approach that focuses primarily on downlink-related XR processing can exceed the expected levels for lightweight, small form factor XR wearable smart glasses (ranging from approximately 1.5 watts to 3 watts).

[0094] Other split-processing XR methods may involve offloading processing to a relatively close companion device (e.g., a UE) or splitting processing between the XR device, the companion UE, and the base station (e.g., a gNB). From the XR device's perspective, this splitting can be based on similar processing loads and local coverage functionality on the XR device side. Utilizing local short-range communication links with the associated UE (via a 5G NR sidelink or WiFi), this method helps reduce modem-related power consumption. Figure 5 Figure 500 illustrates an example of a split-type XR method. Figure 5 In this process, the XR device 506 (which may be, for example, augmented reality (AR) glasses) can offload the process to various components connected to it, such as the UE 502, the base station 504, and the cloud server 508.

[0095] Another split-type XR approach involves offloading processing from the XR device to its companion device (e.g., a companion UE or a combination of a UE and a base station). This approach aims to transform the XR device into a primary input / output (I / O) unit that can share local sensor information with the UE without preprocessing and receive rendered video to be directly displayed from the UE without post-processing. Compared to the split-type XR approach, this method can reduce the power consumption of the XR device (e.g., by approximately 50%). As an example, by transforming the XR glasses into something closer to a pure I / O device, the complexity associated with both transmission (Tx) and reception (Rx) in the XR device can be largely transferred to the companion device or the UE. This goal can be followed across all functional components of the XR device, including PHY / modem-related complexities.

[0096] Much of the complexity in a modem is related to Rx-side processing. Low-complexity, low-power, and low-latency XR-side link designs and waveforms can be achieved through complexity reduction methods for different PHY Rx components. Figure 6 This is a diagram 600 illustrating an example physical (PHY) layer Rx architecture. Figure 6 In this context, it can be assumed that the use of “continuous” uplink (UL) and downlink (DL) channels utilizing subband full-duplex (SBFD) or frequency division duplex (FDD) allows for a PHY method in which most of the complexity associated with Rx baseband (BB) processing can be offloaded to the transmit (Tx) side, significantly reducing XR device complexity and power consumption. For example, in... Figure 6 In this process, one or more RX PHY modules can be downgraded or effectively moved from the XR Rx side to the Tx side. This move allows XR devices to undergo minimal processing, resulting in a significant reduction in Rx modem complexity and power consumption. Figure 6 A transmitter 650 is illustrated in which a signal is transmitted to a receiver on channel 651, and example aspects of the processing occurring at the receiver for receiving the signal from the transmitter are illustrated. For example, digital front-end (FE) 612 and Fast Fourier Transform (FFT) 614 processing are performed. For example, in Figure 6In this process, loop management for carrier frequency offset (CFO) and symbol timing offset (STO) estimation and synchronization (at 602) for XR can be performed on the UE side, where correction updates indicated by the UE to the paired XR device are applied locally. Processing for channel estimation 604 can be distributed between the Rx and Tx sides for non-reciprocal channels (e.g., FDD / SBFD), where "channel sampling" (which can be indicated to the Tx side) is performed only on the Rx side. For channel equalization 606, spatial-frequency equalization can be moved to the Tx side (using nonlinear or linear Tx pre-equalization). For noise estimation 608, with channel equalization 606 moved to the Tx side, local noise / interference filtering / interference suppression combination (IRC) may not be used on the Rx side, and the log-likelihood ratio (LLR) scaled reference signal (RS) used for peak-to-peak error vector magnitude (pp EVM) measurement can be used to dynamically track interference for decoding. For example, Figure 6 An example LLR calculation at 609 is illustrated. STO, CFO estimation (e.g., 602), and channel equalization can consume significant power at the receiver. As the complexity of one or more of the STO, CFO estimation 602, channel estimation 604, channel equalization 606, or noise estimation 608 decreases, lower-complexity decoding 610 can be employed on the Rx side, as presented herein.

[0097] exist Figure 6 In this context, some PHY module transfers can assume "quasi-continuous" channel state information (CSI) knowledge of the channel. For scenarios lacking channel reciprocity, this can be achieved by incorporating SBFD or FDD transmission techniques into the XR sidelink.

[0098] The example aspects presented herein provide methods and apparatus for reducing, eliminating, or removing receiver complexity associated with Rx equalization, which is one of the key complexity contributors at the modem, from XR devices. This reduction in complexity on the modem side of the XR device can be achieved by applying a Tx pre-equalizer on the UE or companion device side instead of applying Rx equalization on the XR device side (i.e., shifting equalization complexity from the receiver to the transmitter).

[0099] Using spatial-frequency Tx pre-equalization allows for effective channel inversion from the transmitter side. Therefore, as seen from the receiver's perspective, the communication channel becomes an almost additive white Gaussian noise (AWGN) channel with a predefined orthogonal multiple-input multiple-output (MIMO) layer (this can be pre-assumed by defining it when using Tx pre-equalization). This simplifies the receiver or XR device, as several resource-intensive processing stages can be skipped. In some respects, the use of spatial-frequency Tx pre-equalization is suitable for orthogonal frequency division multiplexing (OFDM) waveforms (with some adjustments), and the channel information or CSI of the UE-to-XR link may be known to the transmitter side (UE) for channel inversion / pre-equalization and inter-layer interference pre-cancellation.

[0100] The use of a Tx pre-equalizer helps reduce the equalization complexity on the Rx side by applying signal pre-equalization at the transmitter device. In some respects, several pre-equalizations may exist as alternative options that can be used in the Tx pre-equalizer.

[0101] In some examples, the Tx pre-equalizer can be a linear Tx pre-equalizer that uses both Tx zero-forcing (ZF) and Tx minimum mean square error (MMSE) pre-equalization. The ZF pre-equalization method eliminates channel and interference effects by applying channel inversion. On the other hand, MMSE pre-equalization minimizes the mean square error between the transmitted and received signals, while optimally preserving the trade-off between residual channel distortion and noise enhancement. Therefore, MMSE pre-equalization can provide better results than ZF pre-equalization. Figure 7A Figure 700 illustrates an example linear pre-equilibrium scheme on the Tx side according to various aspects of this disclosure. Figure 7A In the Tx side, it can be the input data of the source bitstream. b 702 can obtain the source symbol by mapping each layer through constellations 704. s 706. Source symbol s 706 can undergo Tx pre-equalization P 708 and inverse fast Fourier transform (IFFT) 710. The resulting pre-equalized signal x 712 can be experienced 1 / g 714 and channel transmission H 716 has been sent to the receiver side. Noise can be added during transmission to the receiver side. n 718. In Figure 7A In the middle, as shown at positions 714 and 716, g H represents the TX scaling factor, which can conform to either the total Tx power limit or the daily antenna Tx power limit, and H represents the channel. At the receiver side, the received signal can undergo... g 720, FFT 722 to obtain the estimated sign 724, and the estimated number of bits can be obtained after LLR calculation of 726. 728 (decoder output). Figure 7A The examples in the examples are applicable to OFDM waveforms, and similar schemes can be defined for other waveforms, such as DFT extended orthogonal frequency division multiplexing (DFT-S-OFDM) waveforms (and for true single-carrier applications).

[0102] In some examples, the Tx pre-equalizer can be a nonlinear pre-equalizer, which can use either the Tomlinson-Harashima pre-decoder ZF (THP-ZF) pre-equalization or the THP-MMSE pre-equalization. The THP method is a practical and approximate implementation of "dirty paper decoding," optimized to achieve maximum capacity on the channel. Its principle involves using a feedback filter on the Tx side for known interference (spatial inter-layer interference or multipath-related inter-symbol interference (ISI)) pre-cancellation, followed by channel pre-equalization using a feedforward filter. The potential power boost from the feedback filter may be limited by the modulus operator applied on the Tx side and the corresponding module on the Rx side. Figure 7B Figure 750 illustrates examples of nonlinear pre-equalization schemes on the Tx side according to various aspects of this disclosure. Figure 7B Input data b 752 (which can be the source bitstream) can undergo constellation mapping 754 at each layer to obtain the source symbol. s 756. Source Symbol s 756 can undergo a feedback loop including cross-layer interference cancellation (BI 758) and modulo operation (MOD 760), per-layer scaling (G 762) and feedforward equalization (F 764) to obtain a pre-equalized signal. x 766. Pre-equalized signal x 766 can undergo IFFT 768, 1 / g 770 and channel transmission H 772 is transmitted to the receiver side. Noise can be added during transmission to the receiver side. n 774. In Figure 7B In this context, g represents the TX scaling factor, which can conform to either the total Tx power limit or the daily antenna Tx power limit, and H represents the channel as shown at 772. At the receiver side, the received signal can undergo... g 776, FFT 778, and Modulo operation (MOD 780) are used to obtain the estimated sign. 784. In scenarios employing THP-MMSE pre-equalization, cyclic soft sign extension 782 can be used after the modulo operation (MOD 780) to mitigate modulo-dependent losses on the Rx side. The estimated bit depth can be obtained after LLR computation 786. 788 (decoder output). Figure 7B The examples in the examples are applicable to OFDM waveforms, and similar schemes can be defined for other waveforms, such as DFT-S-OFDM waveforms (and for true single-carrier waveforms).

[0103] Two transmit (Tx) scaling options are available to preserve the allowed transmit power. The first option involves scaling the total power across all antennas, while the second option involves limiting or scaling the maximum power of each antenna. Tx scaling can lead to increased Rx noise, and Tx pre-equalization methods associated with less Tx scaling can result in a higher total signal-to-noise ratio (SNR). Due to modulo operations, THP pre-equalization may be unaffected by any increase in Tx power and therefore has better inter-layer interference mitigation capabilities when used as a continuous interference cancellation (SIC) pre-equalizer on the Tx side, although THP pre-equalization may suffer modulo loss under low SNR conditions.

[0104] In some respects, various types of Tx pre-equalization require not only knowledge of channel state information (CSI) but also of static noise statistics on the Rx side. These static noise statistics include both thermal noise statistics and static interference characteristics, which can be derived from the noise covariance matrix (…). R nn )express.

[0105] In some aspects, Tx pre-equalization can be employed to accommodate the corresponding capabilities of the paired UE side and XR device side. For example, the UE can support Tx pre-equalization and provide some indications or side information to the paired XR device to support a simplified Rx process on the XR device side.

[0106] On the other hand, the XR device can provide all necessary indications to the paired UE to achieve Tx pre-equalization, which may include all or part of the CSI-side information and Rx-side information. R nn Measurement. Furthermore, the XR device may be able to receive certain side information or indications from the UE (or Tx side) for use in Rx side processing employing Tx pre-equalization. Examples of side information or indications may include Rx sample scaling, spatial layer unbiased scaling, and LLR scaling. The XR device may combine this side information or indication with local measurements before utilizing it in a simplified Rx processing flow. For example, LLR scaling may be performed based on local Rx side noise and interference measurements, as well as residual equalization and channel estimation error components, which can be evaluated on the Tx side and indicated to the Rx side to improve performance.

[0107] In some respects, applying Tx pre-equalization on the UE side allows for a significant reduction in complexity on the XR device side (e.g., the complexity of the Rx modem) while maintaining roughly the same performance as achieved using conventional Rx-side equalization. In some examples, Tx pre-equalization can lead to performance improvements, although support for Tx pre-equalization may require low-latency signaling between the Tx and Rx sides.

[0108] Figure 8 This is a block diagram 800 illustrating an example Tx pre-equalization process according to various aspects of this disclosure. For example... Figure 8 As shown, equalization 802 and CFO estimation 804 can be processes that can be transferred from the Rx side 860 to the Tx side 810. By transferring equalization 802 to the Tx side 810, the complexity on the Rx side can be reduced. When performing equalization on the Tx side, Tx power constraints (e.g., total power constraints for all antennas, daily antenna power constraints, or FCC power constraints for ultra-wideband (UWB)) can be considered, and the Rx CSI information can be known on the Tx side. On the Rx side 860, when using a THP pre-equalization scheme (such as THP-ZF pre-equalization or THP-MMSE pre-equalization), a modulo operation (Mod 852) can be added. LLR scaling estimation 854 can improve robustness against interference and CSI aging with a small (e.g., <1.5%) overhead. In some examples, when using modulo operation (Mod 852), cyclic constellation extensions (such as the cyclic constellation extension in 782) can be utilized to enhance LLR calculation 856 to mitigate modulo-dependent losses on the Rx side. With equalization 802 shifted to the Tx side 810, the received signal can be decoded using low-complexity decoder 858 on the Rx side 860.

[0109] In some respects, to support Tx pre-equalization, XR devices can report their capabilities so that they can utilize Tx-side pre-equalization for receiving and processing transmissions at the UE or accompanying equipment.

[0110] For example, if both the XR and the UE are capable of supporting Tx pre-equalization and related procedures, the UE (which can act as a transmitter device for the XR sidelink) can indicate the selected Tx pre-equalization method and transmission scheme (Tx or Rx equalization) to the XR device. Pre-equalization can refer to equalization performed at the transmitter before transmission to the receiver, in order to reduce or avoid equalization processing at the receiver. After capability negotiation, before the transmission of application data with pre-equalization begins, the UE can indicate the transmission scheme or Tx pre-equalization method to the XR device via RRC configuration.

[0111] After receiving Rx CSI information on the Tx side, for example, after the supporting equipment receives CSI from the XR equipment, Tx pre-equalization can be used. If updated CSI information is not available from the receiving equipment, the transmitting equipment may decide to fall back to equalization at the receiver (e.g., in the absence of pre-equalization at the transmitter) until updated CSI information is obtained, thus ensuring a robust communication link. To allow for maximum flexibility, robustness, and dynamic adaptation, DCI, Media Access Control (MAC)-Control Element (MAC-CE), or some other control signaling mechanism can be used to dynamically indicate the transmission scheme adopted or the choice between Tx-side equalization and Rx-side equalization based on synchronization layer 1 (L1) or layer 2 (L2) signaling.

[0112] CSI acquisition for Tx pre-equalization can be performed differently depending on channel reciprocity. In the absence of channel reciprocity, such as in SBFD or FDD, the XR device can signal CSI-related information (or partial CSI) to the UE (e.g., as a companion device). In some examples, signaling for CSI-related information can be performed more efficiently by signaling the original Rx signal samples or channel samples to the UE or companion device, achieving lower complexity at the XR device. The UE can then perform Rx-side channel and noise estimation on the original samples locally (e.g., at the UE), thereby reducing the complexity of the XR device to enable the UE to understand the CSI.

[0113] In some respects, several Tx pre-equalization techniques (such as those based on the MMSE standard) can be based on the Tx / UE side's statistics on Rx noise from the XR device (e.g., R nn This relates to the understanding of noise on the Rx side. In some examples, Rx-side noise information can be derived based on the indicated raw Rx-side data or channel samples given to the Tx side by the Rx side. In these cases, the XR device may not provide additional noise-related indications.

[0114] In some respects, the TX pre-equalization process can be applied to scenarios where channel reciprocity is absent (SBFD / FDD transmission schemes). In such scenarios, uplink (UL) channel estimation cannot be used to obtain CSI for Tx pre-equalization because the UL channel and downlink (DL) channel may operate on different frequency bands or ranges, and channel reciprocity may not exist. In these cases, CSI-side information or indications can be sent from the XR device to the UE.

[0115] CSI-side information can be transmitted in various ways. In some examples, transmission can be implicit, where the XR device can indicate or report raw data or channel samples (referred to as "sampled channels") to the UE. In this scenario, the UE can evaluate Rx-side noise statistics or... R nn (Channel and noise can be separated along the channel estimation process on the UE side). In some examples, transmission can be explicit, where the XR device can directly indicate the estimated CSI to the UE. To facilitate this, the XR device can perform local channel estimation based on a dedicated pilot (e.g., a reference signal) in the DL, and the XR device can signal the obtained channel estimate to the UE. In this scenario, Rx-side noise statistics or R nn It can also be measured locally by the XR device and subsequently indicated to the UE. For both implicit and explicit transmission of CSI-side information, there may be no reciprocity between Tx and Rx noise characteristics, and the Rx-side noise information ( R nn The XR signal can be sent to the UE.

[0116] Figure 9 Figure 900 illustrates an example transmission of channel information from an XR device to a UE according to various aspects of this disclosure. Figure 9 In this process, XR device 904 receives DL RS transmission 920 from, for example, UE 902. XR device 904 can perform various processes based on the DL RS, including DL RS sampling (e.g., at 906) and quantization (e.g., at 908), scrambling and CRC insertion (e.g., at 910), encoding and modulation (e.g., at 912). XR device 904 can then transmit the processed data to UE 902 via UL transmission 930. On the UE side, UE 902 can process the data received from XR device 904. This process may include decoding and demodulation (e.g., at 932), descrambling CRC check (e.g., at 934), and IQ sample reconstruction (e.g., at 936). Based on the received data, UE 902 can perform various evaluations or estimates related to the pre-equalization process, including STO estimation (e.g., at 938), channel estimation (e.g., at 940), noise estimation, and so on. R nnAn estimation is performed (e.g., at 942). Based on the evaluation and estimation, UE 902 may apply a pre-equalization process (at 950) to the signal to be transmitted to XR device 904, and transmit the pre-equalized signal to XR device 904 (e.g., at 960). As used herein, the terms “DL” or “UL” are used to describe communication between the UE and the associated XR device, and these terms may indicate the direction of communication without specifying the characteristics of the channel. For example, “DL” may indicate transmission from the UE to the XR device, and “UL” may indicate transmission from the XR device to the UE. Communication between the UE and the XR device may be transmitted via a sidelink channel.

[0117] Figure 10 This is a call flowchart 1000 illustrating a wireless communication method according to various aspects of this disclosure. Various aspects are described in conjunction with a UE 1002, a base station 1004, and a receiving device 1006 (which may be an XR device). [The remaining text appears to be incomplete and requires further context.] Figure 10 The aspects performed by base station 1004 in the aggregation may be performed by base stations in the aggregation and / or by one or more components of base station 1004 (e.g., such as CU110, DU 130, and / or RU 140). In some aspects, base station 1004 or one or more components of base station 1004 may be referred to as network nodes or network entities. Although this document (e.g., in Figure 10 as well as Figures 5 to 9 The present invention describes aspects of an example XR device as receiving device 1006, but these aspects can be implemented by any receiver to reduce the complexity at the receiver. Although this document (e.g., in Figure 10 as well as Figures 5 to 9 The text describes aspects of UE 1002 used to facilitate the exchange of communication between the network and the receiving device, but these aspects can be performed by another device that acts as a transmitter to the receiving device, and UE 1002 can be referred to as an accessory device or transmitter device.

[0118] like Figure 10 As shown, at 1008, the UE can receive communication from base station 1004 and can generate a pre-equalized signal based on the communication to provide to the XR device. For example, the pre-equalized signal from UE 1002 to receiving device 1006 may include communication from base station 1004 to receiving device 1006.

[0119] At 1010, UE 1002 can perform pairing and establish an initial link with receiving device 1006. The link (or channel) between UE 1002 and receiving device 1006 can be, for example, a sidelink channel.

[0120] At 1012, UE 1002 may communicate a capability indication to receiving device 1006. This capability indication may indicate support for the pre-equalization process. In some examples, UE 1002 may send a capability indication to receiving device 1006 indicating UE 1002's support for the pre-equalization process. In some examples, UE 1002 may receive a capability indication from receiving device 1006 indicating receiving device 1006's support for the pre-equalization process. UE 1002 and receiving device 1006 may communicate RRC configuration.

[0121] In box 1014, UE 1002 may send a DL reference signal (RS) to the receiving device. The DL RS may not be pre-equalized at UE 1002.

[0122] At 1016, upon receiving an RS, receiving device 1006 can process the received RS. For example, receiving device 1006 can perform sampling and quantization on the DL RS at 1006.

[0123] In some examples, at 1018, receiving device 1006 may estimate the Rx CSI of the channel between UE 1002 and receiving device 1006 based on the received DL RS.

[0124] In some examples, at 1020, receiving device 1006 can estimate channel noise information, such as the noise covariance matrix, of the channel between UE 1002 and receiving device 1006.

[0125] At 1022, receiving device 1006 may send UL data and DL RS sample indication to UE 1002. UL data may include, for example, channel information of the channel between UE 1002 and receiving device 1006. As an example, channel information may include the Rx CSI estimated at 1018 and channel noise information estimated at 1020. The DL RS sampling indication may include a set of samples based on DL RS.

[0126] At 1024, UE 1002 can process the received UL data and DL RS sample indication. For example, at 1026, UE 1002 can perform UL demodulation and decoding on the received UL data. At 1028, the UE can obtain DLCSI based on DL RS samples. At 1030, UE 1002 can obtain DL noise based on DL RS samples.

[0127] At 1032, based on channel information such as CSI (obtained at 1028) or channel noise (obtained at 1030), UE 1002 can assess whether it is feasible to perform pre-equalization on the UE side (Tx side).

[0128] If UE 1002 determines that performing pre-equalization on the UE side (Tx side) is not feasible, UE 1002 may transmit a signal at 1034 without pre-equalization on the UE side. In this case, receiving device 1006 may perform a regular equalization process on the received signal on the receiver side.

[0129] If UE 1002 determines that it is feasible to perform pre-equalization on the UE side (Tx side), then UE 1002 may perform the pre-equalization process on the signal to be sent to receiving device 1006.

[0130] At 1038, UE 1002 may send a pre-equalization indicator to receiving device 1006. The pre-equalization indicator may instruct receiving device 1006 to use a simplified reception procedure (e.g., skip the equalization procedure) for the pre-equalized signal received at 1038. In some examples, the pre-equalization indicator may further indicate the pre-equalization method used in the pre-equalization process at 1036 (e.g., ZF, ZF-MMSE, THP-ZF, or THP-MMSE).

[0131] At 1040, base station 1004 can send a pre-equalized signal to receiving device 1006. Receiving device 1006 can perform DL data decoding at 1042. Since the signal has already been pre-equalized on the UE side, receiving device 1006 can use a simplified scheme for decoding (e.g., low-complexity decoding 858), thereby reducing power consumption on receiving device 1006.

[0132] In some examples, at 1040, in addition to the pre-equalized signal, UE 1002 may transmit another DL RS, which allows receiving device 1006 to provide UE 1002 with closer channel information. Upon receiving the DL RS at 1040, the XR device may repeat steps similar to those used for the earlier DL RS. For example, receiving device 1006 may perform DL RS sampling and quantization on the new DL RS (at 1044) and send a DL RS sampling indication to UE 1002 (at 1046).

[0133] At 1048, UE 1002 can process received data (such as DL RS sample indication) to obtain closer channel information.

[0134] Figure 11 This is a flowchart 1100 illustrating a method for wireless communication at a UE according to various aspects of this disclosure. The method can be performed by the UE. The UE can be UE 104, 350, 902, 1002, or... Figure 15The hardware implementation of the apparatus 1504 allows the UE to perform a transmitter-side pre-equalization process on the signal before sending the pre-equalized signal to the XR device. This method shifts the complexity related to equalization from the XR device to the UE, thereby reducing the computational burden on the XR device and allowing for simpler and more portable / wearable hardware designs for the XR device.

[0135] like Figure 11 As shown, at 1102, the UE can obtain channel information of the sidelink channel between the UE and the receiving device. The receiving device can be an XR device, such as XR device 506, 904 or receiving device 1006. Figure 9 and Figure 10 Various aspects of the steps combined with flowchart 1100 are illustrated. For example, refer to... Figure 10 UE 1002 can obtain channel information (e.g., DL RS sample indication) of the sidelink channel between UE 1002 and the receiving device (e.g., 1006) at 1022. (See reference...) Figure 9 UE 902 can obtain channel information (UL transmission 930) from XR device 904. The channel information may include channel estimation and noise estimation for the sidelink channel between UE 1002 and receiving device (e.g., 1006). In some examples, 1102 may be performed by transmitter pre-equalization component 198.

[0136] At 1104, the UE can perform a pre-equalization process on the signal to be transmitted to the receiving device based on channel information to obtain a pre-equalized signal. For example, refer to Figure 10 UE 1002 can perform a pre-equalization process at 1036 based on channel information on the signal to be transmitted to the receiving device (1006) to obtain a pre-equalized signal. (See reference...) Figure 9 UE 902 may perform a pre-equalization process on the signal at 950 to obtain a pre-equalized signal for XR device 904 (at 960). In some examples, 1104 may be performed by transmitter pre-equalization component 198.

[0137] At position 1106, the UE can transmit a pre-equalized signal to the receiving device via the sidelink channel. For example, refer to... Figure 10 UE 1002 can transmit a pre-equalized signal (1006) to the receiving device via the sidelink channel at position 1040. (See reference) Figure 9 UE902 can send a pre-equalization signal to the receiving device (XR device 904) at 960. In some examples, 1106 can be performed by the transmitter pre-equalization component 198.

[0138] Figure 12This is a flowchart 1200 illustrating a method for wireless communication at a UE according to various aspects of this disclosure. The method can be performed by the UE. The UE can be UE 104, 350, 902, 1002, or... Figure 15 The hardware implementation of the apparatus 1504 allows the UE to perform a transmitter-side pre-equalization process on the signal before sending the pre-equalized signal to the XR device. This method shifts the complexity related to equalization from the XR device to the UE, thereby reducing the computational burden on the XR device and allowing for simpler and more portable / wearable hardware designs for the XR device.

[0139] like Figure 12 As shown, at 1208, the UE can obtain channel information of the sidelink channel between the UE and the receiving device. The receiving device can be an XR device, such as XR device 506, 904, or receiving device 1006. Figure 9 and Figure 10 Various aspects of the steps combined with flowchart 1200 are illustrated. For example, refer to... Figure 10 UE 1002 can obtain channel information (e.g., DL RS sample indication) of the sidelink channel between UE 1002 and receiving device (1006) at 1022. (See reference...) Figure 9 UE 902 can obtain channel information (UL transmission 930) from XR device 904. In some examples, the channel information may include channel estimation (at 1018) and noise estimation (at 1020) for the sidelink channel between UE 1002 and receiving device (1006). In some examples, 1208 may be performed by transmitter pre-equalization component 198.

[0140] At point 1216, the UE can perform a pre-equalization process on the signal to be transmitted to the receiving device based on channel information to obtain a pre-equalized signal. For example, refer to Figure 10 UE 1002 can perform a pre-equalization process at 1036 based on channel information on the signal to be transmitted to the receiving device (1006) to obtain a pre-equalized signal. (See reference...) Figure 9 UE 902 may perform a pre-equalization process on the signal at 950 to obtain a pre-equalized signal for XR device 904 (at 960). In some examples, 1216 may be performed by transmitter pre-equalization component 198.

[0141] At position 1220, the UE can transmit a pre-equalized signal to the receiving device via the sidelink channel. For example, refer to... Figure 10 UE 1002 can transmit a pre-equalized signal (1006) to the receiving device via the sidelink channel at position 1040. (See reference) Figure 9UE902 can send a pre-equalization signal to the receiving device (XR device 904) at 960. In some examples, 1220 can be performed by the transmitter pre-equalization component 198.

[0142] In some respects, to transmit the pre-equalized signal (at 1220), the UE can use either the SBFD scheme or the FDD scheme to transmit the pre-equalized signal via a set of OFDM symbols. For example, refer to Figure 10 UE 1002 can use the SBFD or FDD scheme at 1040 to transmit pre-equalized signals via a set of OFDM symbols.

[0143] In some aspects, at 1218, the UE may send a pre-equalization indicator to the receiving device, which instructs the receiving device to process the pre-equalized signal using a simplified reception procedure. The simplified reception procedure may skip the equalization process for the pre-equalized signal, and the pre-equalization indicator may also include a method indicator indicating the pre-equalization procedure and side information for the simplified reception procedure. For example, refer to... Figure 10 UE 1002 may send a pre-equalization indicator to receiving device (1006) at 1038. The pre-equalization indicator may instruct receiving device (1006) to process the pre-equalized signal using a simplified reception procedure. The simplified reception procedure may skip the equalization process for the pre-equalized signal, and the pre-equalization indicator may also include a method indicator indicating the pre-equalization procedure and side information for the simplified reception procedure. In some examples, 1218 may be performed by transmitter pre-equalization component 198.

[0144] In some respects, the pre-equalization indicator can be sent via one or more of the following (at 1218): RRC configuration, DCI, or MAC-CE. For example, see reference... Figure 10 The pre-equalization indicator can be sent via one or more of the following (at 1038): RRC configuration, DCI, or MAC-CE.

[0145] In some respects, at 1204, the UE may receive from the receiving device a receiver capability indicator indicating the receiving device's support for the pre-equalization procedure. To perform the pre-equalization procedure (at 1216), the UE may perform the pre-equalization procedure in response to the receiver capability indicator. For example, refer to... Figure 10 At 1012, UE 1002 may receive a receiver capability indicator indicating that the receiving device (1006) supports the pre-equalization process. UE 1002 may perform the pre-equalization process based on the receiver capability indicator (at 1036). In some examples, 1204 may be performed by the transmitter pre-equalization component 198.

[0146] In some respects, at 1206, the UE can transmit a dedicated reference signal to the receiving device. Channel information (at 1208) can be based on the dedicated reference signal. For example, reference... Figure 10 UE 1002 can transmit a dedicated reference signal (DL RS) to the receiving device (1006) at 1014. Reference Figure 9 UE 902 may transmit a dedicated reference signal (DL RS transmission 920) (1006) to the receiving device. Channel information (e.g., UL transmission at 930) may be based on the dedicated reference signal. In some examples, 1206 may be performed by the transmitter pre-equalization component 198.

[0147] In some respects, channel information (at 1208) may include Rx CSI associated with the sidelink channel. For example, refer to Figure 10 Channel information (received by UE 1002 at 1022) may include Rx CSI associated with the sidelink channel.

[0148] In some respects, to obtain channel information (at 1208), the UE can receive a set of received samples based on a dedicated reference signal (transmitted at 1206) from the receiving device at 1222, and identify the Rx CSI associated with the sidelink channel based on this set of received samples. For example, the reference... Figure 10 At 1022, UE 1002 may receive a set of received samples based on a dedicated reference signal from the receiving device (1006). At 1028, UE 1002 may identify the Rx CSI associated with the sidelink channel based on this set of received samples. In some examples, 1222 may be performed by the transmitter pre-equalization component 198.

[0149] In some respects, to obtain channel information (at 1208), the UE can receive the Rx CSI associated with the sidelink channel from the receiving device at 1224. The Rx CSI can be based on a dedicated reference signal (at 1206). For example, the reference... Figure 10 The receiving device 1006 can estimate the Rx CSI at 1018 and send the Rx CSI to the UE 1002 at 1022. In some examples, 1224 can be performed by the transmitter pre-equalization component 198.

[0150] In some aspects, channel information may also include channel noise information, which includes the noise covariance matrix associated with the sidelink channel. For example, refer to Figure 10 The channel information (received by UE 1002 at 1022) may also include channel noise information, which includes the noise covariance matrix associated with the sidelink channel.

[0151] In some respects, to obtain channel information (at 1208), the UE can receive a set of received samples based on a dedicated reference signal from the receiving device at 1222; and identify channel noise information based on this set of received samples. For example, the reference... Figure 10 UE 1002 can receive a set of received samples based on a dedicated reference signal at 1022. UE 1002 can use this set of received samples to identify channel noise information (at 1030).

[0152] In some respects, in order to obtain channel information (at 1208), the UE can receive channel noise information from the receiving device at 1226. For example, refer to Figure 10 The receiving device 1006 can estimate the channel noise information at 1020 and transmit the channel noise information to the UE 1002 at 1022. In some examples, 1226 can be performed by the transmitter pre-equalization component 198.

[0153] In some respects, the pre-equalization process (at 1216) may include a linear pre-equalization process, which includes one or more of the following: ZF pre-equalization, or MMSE pre-equalization. For example, refer to Figure 10 The pre-equilibrium process (at 1036) may include a linear pre-equilibrium process, which includes one or more of the following: ZF pre-equilibrium or MMSE pre-equilibrium.

[0154] In some aspects, the pre-equalization process (at 1216) may include a nonlinear pre-equalization process, which includes one or more of the following: THP-ZF pre-equalization, or THP-MMSE pre-equalization. For example, refer to Figure 10 The pre-equalization process (at 1036) may include a nonlinear pre-equalization process, which includes one or more of the following: THP-ZF pre-equalization or THP-MMSE pre-equalization.

[0155] In some respects, at 1210, the UE can evaluate the validity of the channel information used to perform the pre-equalization process (at 1216). If the channel information is valid for performing the pre-equalization process, the UE can perform the pre-equalization process (at 1216). Based on whether the channel information is valid for performing the pre-equalization process (at 1212), the UE can skip the pre-equalization process for the signal on the UE side at 1214 (if the channel information is invalid for performing the pre-equalization process) and send the signal to the receiving device for the receiving device to perform a regular equalization process on the received signal. For example, refer to Figure 10At 1032, UE 1002 may evaluate the validity of the channel information used to perform the pre-equalization process (at 1036). If the channel information is valid for performing the pre-equalization process, UE 1002 may perform the pre-equalization process (at 1036). If the channel information is invalid for performing the pre-equalization process at UE 1002, UE 1002 may skip the pre-equalization process for the signal on UE 1002 and send a signal to the receiving device (1006) at 1034 for the receiving device (1006) to perform a regular equalization process on the signal. In some examples, 1212 and 1214 may be performed by the transmitter pre-equalization component 198.

[0156] In some respects, at point 1202, the UE can receive communication for the receiving device from a network entity. The pre-equalization signal from the UE to the receiving device may include communication for the receiving device from the network entity. This network entity may be... Figure 1 The base station or base station component in the access network, or core network component (e.g., base station 102, 310, 1004; or Figure 15 (Network entity 1502 in the specific hardware implementation). For example, refer to... Figure 10 UE 1002 can receive communication for receiving device (1006) from network entity (base station 1004). The pre-equalization signal from UE 1002 to receiving device (XR device 1006) (at 1040) can include communication from network entity (base station 1004) for receiving device (1006). In some examples, 1202 can be performed by transmitter pre-equalization component 198.

[0157] Figure 13 This is a flowchart 1300 illustrating a method for wireless communication at a receiving device according to various aspects of this disclosure. The method can be performed by the receiving device. The receiving device can be an XR device, such as XR device 506, 904, or receiving device 1006. This method allows the UE to perform a transmitter-side pre-equalization process on the signal before sending the pre-equalized signal to the XR device. This method shifts the complexity associated with equalization from the XR device to the UE, thereby reducing the computational burden on the XR device and allowing for simpler and more portable / wearable hardware designs for the XR device.

[0158] like Figure 13 As shown, at position 1302, the receiving device can receive a dedicated reference signal from the UE. The UE can be UE 104, 350, 902, 1002, or... Figure 15 The hardware implementation of the device 1504. Figure 9 and Figure 10 Various aspects of the steps combined with flowchart 1300 are illustrated. For example, refer to... Figure 10The receiving device (1006) can receive a dedicated reference signal (DL RS) from UE 1002 at point 1014. Reference Figure 9 The receiving device (XR device 904) can receive a dedicated reference signal (e.g., DLRS transmission 920) from the UE 902.

[0159] At 1304, the receiving device can transmit channel information of the sidelink channel between the UE and the receiving device to the UE based on a dedicated reference signal. For example, the reference... Figure 10 The receiving device (1006) can transmit channel information of the sidelink channel between the UE and the receiving device to the UE 1002 at point 1022 based on a dedicated reference signal. Reference Figure 9 The receiving device (1006) can send channel information to UE902 (e.g., UL sends 930).

[0160] At 1306, the receiving device can receive the pre-equalized signal from the UE. For example, refer to Figure 9 and Figure 10 The receiving device (XR device 904 or receiving device 1006) can receive pre-equalized signals (960, 1040) from UE 902, 1002.

[0161] At 1308, the receiving device can use a simplified reception procedure to process the pre-equalized signal. The simplified reception procedure skips the equalization process for the pre-equalized signal. For example, refer to... Figure 10 The receiving device (1006) can use a simplified receiving process (e.g., low-complexity decoding 858) at 1042 to process the pre-equalized signal.

[0162] Figure 14 This is a flowchart 1400 illustrating a method for wireless communication at a receiving device according to various aspects of this disclosure. The method can be performed by the receiving device. The receiving device can be an XR device, such as XR device 506, 904, or receiving device 1006. This method allows the UE to perform a transmitter-side pre-equalization process on the signal before sending the pre-equalized signal to the XR device. This method shifts the complexity associated with equalization from the XR device to the UE, thereby reducing the computational burden on the XR device and allowing for simpler and more portable / wearable hardware designs for the XR device.

[0163] like Figure 14 As shown, at position 1404, the network entity can receive a dedicated reference signal from the UE. The UE can be UE 104, 350, 902, 1002, or... Figure 15 The hardware implementation of the device 1504. Figure 9 and Figure 10 Various aspects of the steps combined with flowchart 1400 are illustrated. For example, refer to... Figure 10 The receiving device (1006) can receive a dedicated reference signal (DL RS) from UE 1002 at point 1014. Reference Figure 9 The receiving device (XR device 904) can receive a dedicated reference signal (e.g., DLRS transmission 920) from the UE 902.

[0164] At point 1412, the receiving device can transmit channel information of the sidelink channel between the UE and the receiving device to the UE based on a dedicated reference signal. For example, the reference... Figure 10 The receiving device (1006) can transmit channel information of the sidelink channel between the UE and the receiving device to the UE 1002 at point 1022 based on a dedicated reference signal. Reference Figure 9 The receiving device (1006) can send channel information to UE902 (e.g., UL sends 930).

[0165] At position 1416, the receiving device can receive the pre-equalized signal from the UE. For example, refer to... Figure 9 and Figure 10 The receiving device (XR device 904 or receiving device 1006) can receive pre-equalized signals (960, 1040) from UE 902, 1002.

[0166] At 1418, the receiving device can use a simplified reception procedure to process the pre-equalized signal. The simplified reception procedure skips the equalization process for the pre-equalized signal. For example, refer to... Figure 10 The receiving device (1006) can use a simplified receiving process (e.g., low-complexity decoding 858) at 1042 to process the pre-equalized signal.

[0167] In some respects, to receive the pre-equalized signal (at 1416), the receiving device can use either the SBFD or FDD scheme to receive the pre-equalized signal via a set of OFDM symbols. For example, see reference... Figure 10 The receiving device (1006) can use the SBFD or FDD scheme at 1040 to receive the pre-equalized signal via a set of OFDM symbols.

[0168] In some aspects, at 1414, the receiving device may receive from the UE a pre-equalization indicator that indicates a simplified reception procedure for the pre-equalization signal. The pre-equalization indicator may also include a method indicator indicating the pre-equalization procedure performed on the pre-equalized signal and side information for the simplified reception procedure. For example, refer to... Figure 10At 1038, the receiving device (1006) may receive a pre-equalization indicator from the UE 1002. The pre-equalization indicator may instruct the receiving device (1006) to process the pre-equalized signal using a simplified receiving procedure. The simplified receiving procedure may skip the equalization process for the pre-equalized signal, and the pre-equalization indicator may also include a method indicator indicating the pre-equalization process and side information for the simplified receiving procedure.

[0169] In some respects, the pre-equalization indicator can be received via one or more of the following (at 1414): RRC configuration, DCI, or MAC-CE. For example, see reference... Figure 10 The pre-equalization indicator can be received via one or more of the following (at 1038): RRC configuration, DCI, or MAC-CE.

[0170] In some respects, at 1402, the receiving device may send a receiver capability indicator to the UE indicating support for the pre-equalization process. For example, refer to Figure 10 The receiving device (1006) may send a receiver capability indicator at 1012 indicating support for the pre-equalization process.

[0171] In some respects, channel information includes Rx CSI associated with the sidelink channel. For example, refer to Figure 10 Channel information (transmitted by receiving device 1006 at 1022) may include Rx CSI associated with the sidelink channel.

[0172] In some respects, at 1406, the receiving device can obtain a set of received samples based on a dedicated reference signal (at 1404). To transmit channel information (at 1412), the receiving device can send a set of received samples to the UE. For example, the reference... Figure 10 The receiving device (1006) can obtain a set of received samples at 1016 and send the set of received samples (DL RS sample indication) to UE 1002 at 1022.

[0173] In some respects, at 1408, the receiving device can estimate the Rx CSI associated with the sidelink channel based on a dedicated reference signal. To transmit channel information (at 1412), the receiving device can send the Rx CSI to the UE. For example, the reference... Figure 10 The receiving device (1006) can estimate the Rx CSI at 1018 and send the Rx CSI to the UE 1002 at 1022.

[0174] In some aspects, channel information may also include channel noise information, which includes the noise covariance matrix associated with the sidelink channel. For example, refer to Figure 10The channel information (transmitted by receiving device 1006 at 1022) may also include channel noise information, which includes the noise covariance matrix associated with the sidelink channel. R nn ).

[0175] In some respects, at 1410, the receiving device can estimate channel noise information based on a dedicated reference signal. For example, the reference... Figure 10 The receiving device (receiving device 1006) can estimate the channel noise information at 1020.

[0176] Figure 15Figure 1500 illustrates an example of a hardware implementation for device 1504. Device 1504 may be a UE, a component of a UE, or implement UE functionality. In some aspects, device 1504 may include at least one cellular baseband processor (or processing circuitry) 1524 (also referred to as a modem) coupled to one or more transceivers 1522 (e.g., cellular RF transceivers). Cellular baseband processor (or processing circuitry) 1524 may include at least one on-chip memory (or memory circuitry) 1524'. In some aspects, device 1504 may also include one or more Subscriber Identity Module (SIM) cards 1520, and at least one application processor (or processing circuitry) 1506 coupled to a Secure Digital Card (SD) card 1508 and a screen 1510. Application processor (or processing circuitry) 1506 may include on-chip memory (or memory circuitry) 1506'. In some aspects, device 1504 may also include a Bluetooth module 1512, a WLAN module 1514, an SPS module 1516 (e.g., a GNSS module), one or more sensor modules 1518 (e.g., a barometric pressure sensor / altimeter; motion sensors such as an inertial measurement unit (IMU), gyroscope, and / or accelerometer; light detection and ranging (LIDAR), radio-assisted detection and ranging (RADAR), sound navigation and ranging (SONAR), magnetometer, audio, and / or other technologies for positioning), an additional memory module 1526, a power supply 1530, and / or a camera 1532. Bluetooth module 1512, WLAN module 1514, and SPS module 1516 may include an on-chip transceiver (TRX) (or in some cases, only a receiver (RX)). Bluetooth module 1512, WLAN module 1514, and SPS module 1516 may include their own dedicated antennas and / or communicate using antenna 1580. Cellular baseband processor (or processing circuitry) 1524 communicates with UE 104 and / or RU associated with network entity 1502 via transceiver 1522 through one or more antennas 1580. Cellular baseband processor (or processing circuitry) 1524 and application processor (or processing circuitry) 1506 may each include computer-readable medium / memory (or memory circuitry) 1524', 1506' respectively. An additional memory module 1526 may also be considered as computer-readable medium / memory (or memory circuitry). Each computer-readable medium / memory (or memory circuitry) 1524', 1506', 1526 may be non-transitory. Cellular baseband processor (or processing circuitry) 1524 and application processor (or processing circuitry) 1506 are each responsible for general processing, including executing software stored on the computer-readable medium / memory (or memory circuitry).When executed by the cellular baseband processor (or processing circuit) 1524 / application processor (or processing circuit) 1506, the software causes the cellular baseband processor (or processing circuit) 1524 / application processor (or processing circuit) 1506 to perform the various functions described above. The cellular baseband processor (or processing circuit) 1524 and the application processor (or processing circuit) 1506 are configured to perform the various functions described above based at least in part on information stored in a memory (or memory circuit). That is, the cellular baseband processor (or processing circuit) 1524 and the application processor (or processing circuit) 1506 can be configured to perform a first subset of the various functions described above without information stored in the memory, and can be configured to perform a second subset of the various functions described above based on information stored in the memory. The computer-readable medium / memory (or memory circuit) can also be used to store data manipulated by the cellular baseband processor (or processing circuit) 1524 / application processor (or processing circuit) 1506 during software execution. The cellular baseband processor (or processing circuitry) 1524 / application processor (or processing circuitry) 1506 may be a component of the UE 350 and may include at least one of a memory 360 and / or a TX processor 368, an RX processor 356, and a controller / processor 359. In one configuration, the device 1504 may be at least one processor chip (modem and / or application) and may only include the cellular baseband processor (or processing circuitry) 1524 and / or the application processor (or processing circuitry) 1506, while in another configuration, the device 1504 may be the entire UE (see, for example, see below). Figure 3 The UE 350 includes an additional module of the device 1504.

[0177] As discussed above, component 198 can be configured to: obtain channel information of the sidelink channel between the UE and the receiving device; perform a pre-equalization process on the signal to be transmitted to the receiving device based on the channel information to obtain a pre-equalized signal; and transmit the pre-equalized signal to the receiving device through the sidelink channel. Component 198 can also be configured to perform combination Figure 11 and Figure 12 The flowchart described and / or by Figure 10Component 198 may be any aspect of the UE 1002's execution. Component 198 may be within the cellular baseband processor (or processing circuitry) 1524, the application processor (or processing circuitry) 1506, or both. Component 198 may be one or more hardware components specifically configured to execute the stated process / algorithm, implemented by one or more processors configured to execute the stated process / algorithm, stored in a computer-readable medium for implementation by one or more processors, or some combination thereof. When multiple processors are implemented, the multiple processors may execute the stated process / algorithm individually or in combination. As shown, apparatus 1504 may include a variety of components configured for various functions. In one configuration, apparatus 1504, and specifically cellular baseband processor (or processing circuit) 1524 and / or application processor (or processing circuit) 1506, includes: components for obtaining channel information of a sidelink channel between the UE and a receiving device; components for performing a pre-equalization process on a signal to be transmitted to the receiving device based on the channel information to obtain a pre-equalized signal; and components for transmitting the pre-equalized signal to the receiving device via the sidelink channel. Apparatus 1504 may also include components for performing a combination... Figure 11 and Figure 12 The flowchart in the document describes the aspects and / or is composed of Figure 10 The component can be any of the aspects performed by UE 1002. The component can be a component 198 of device 1504 configured to perform the functions described therein. As described above, device 1504 may include a TX processor 368, an RX processor 356, and a controller / processor 359. Therefore, in one configuration, these components can be the TX processor 368, the RX processor 356, and / or the controller / processor 359 configured to perform the functions described therein.

[0178] Figure 16Figure 1600 illustrates an example of a hardware implementation for network entity 1602. Network entity 1602 may be a BS, a component of a BS, or implement BS functionality. Network entity 1602 may include at least one of CU 1610, DU 1630, or RU 1640. For example, depending on the layer functionality processed by component 199, network entity 1602 may include: CU 1610; both CU 1610 and DU 1630; each of CU 1610, DU 1630, and RU 1640; DU 1630; both DU 1630 and RU 1640; or RU 1640. CU 1610 may include at least one CU processor (or processing circuitry) 1612. CU processor (or processing circuitry) 1612 may include on-chip memory (or memory circuitry) 1612'. In some aspects, CU 1610 may also include an additional memory module 1614 and a communication interface 1618. CU 1610 communicates with DU 1630 via a midhaul link such as an F1 interface. DU 1630 may include at least one DU processor (or processing circuitry) 1632. DU processor (or processing circuitry) 1632 may include on-chip memory (or memory circuitry) 1632'. In some aspects, DU 1630 may also include an additional memory module 1634 and a communication interface 1638. DU 1630 communicates with RU 1640 via a fronthaul link. RU 1640 may include at least one RU processor (or processing circuitry) 1642. RU processor (or processing circuitry) 1642 may include on-chip memory (or memory circuitry) 1642'. In some aspects, RU 1640 may also include an additional memory module 1644, one or more transceivers 1646, an antenna 1680, and a communication interface 1648. RU 1640 communicates with UE 104. On-chip memories (or memory circuits) 1612', 1632', 1642' and additional memory modules 1614, 1634, 1644 can each be considered as computer-readable media / memory (or memory circuits). Each computer-readable medium / memory (or memory circuit) can be non-transitory. Each of the processors (or processing circuits) 1612, 1632, 1642 is responsible for general processing, including executing software stored on the computer-readable medium / memory (or memory circuit). This software, when executed by the corresponding processor (or processing circuit), causes the processor (or processing circuit) to perform the various functions described above. The computer-readable medium / memory (or memory circuit) can also be used to store data manipulated by the processor (or processing circuit) during software execution.

[0179] As discussed above, component 199 can be configured to perform union. Figure 10The base station 1004 is described in any of the aspects. Component 199 may be located within one or more processors (or processing circuitry) of one or more of CU 1610, DU 1630, and RU 1640. Component 199 may be one or more hardware components specifically configured to execute the stated process / algorithm, implemented by one or more processors configured to execute the stated process / algorithm, stored in a computer-readable medium for implementation by one or more processors, or some combination thereof. When multiple processors are implemented, the multiple processors may execute the stated process / algorithm individually or in combination. Network entity 1602 may include a variety of components configured for various functions. In one configuration, network entity 1602 includes components for executing the process / algorithm by one or more processors. Figure 10 The components of the base station 1004 can be any of the components in various aspects of the operation. A component can be a component 199 of network entity 1602 configured to perform the functions described therein. As described above, network entity 1602 may include a TX processor 316, an RX processor 370, and a controller / processor 375. Therefore, in one configuration, these components can be the TX processor 316, the RX processor 370, and / or the controller / processor 375 configured to perform the functions described therein.

[0180] This disclosure provides a method for wireless communication at a UE. The method may include: obtaining channel information of a sidelink channel between the UE and a receiving device; performing a pre-equalization process on a signal to be transmitted to the receiving device based on the channel information to obtain a pre-equalized signal; and transmitting the pre-equalized signal to the receiving device via the sidelink channel. This method allows the UE to perform a transmitter-side pre-equalization process on the signal before transmitting the pre-equalized signal to an XR device. This method shifts the equalization-related complexity from the XR device to the UE, thereby reducing the computational burden on the XR device and allowing for simpler and more portable / wearable hardware designs for the XR device.

[0181] It should be understood that the specific order or hierarchy of the boxes in the disclosed process / flowcharts is merely an example of the exemplary method. It should be understood that the specific order or hierarchy of the boxes in the process / flowcharts may be rearranged based on design preferences. Furthermore, some boxes may be combined or omitted. The appended method claims present the elements of various boxes in a sample order, but are not limited to the given specific order or hierarchy.

[0182] The foregoing description is provided to enable any person skilled in the art to practice the various aspects described herein. Various modifications to these aspects will be apparent to those skilled in the art, and the general principles defined herein may be applied to other aspects. Therefore, the claims are not limited to the aspects described herein but should be given the full scope consistent with the language of the claims. Unless specifically stated otherwise, references to elements in the singular form do not mean “one and only one” but rather “one or more.” Terms such as “if,” “when,” and “simultaneously” do not imply a direct temporal relationship or reaction. That is, these phrases, such as “when…”, do not imply an immediate action in response to the occurrence of an action or during the occurrence of an action, but simply suggest that if a condition is met, then the action will occur, without requiring a specific or immediate time limit for the occurrence of the action. The word “exemplary” is used herein to mean “serving as an example, instance, or illustration.” Any aspect described herein as “exemplary” is not necessarily to be construed as preferred or superior to other aspects. Unless specifically stated otherwise, the term “some” refers to one or more. Combinations such as "at least one of A, B, or C", "one or more of A, B, or C", "at least one of A, B, and C", "one or more of A, B, and C", and "A, B, C, or any combination thereof" include any combination of A, B, and / or C, and may include multiple A, multiple B, or multiple C. Specifically, combinations such as "at least one of A, B, or C", "one or more of A, B, or C", "at least one of A, B, and C", "one or more of A, B, and C", and "A, B, C, or any combination thereof" may be only A, only B, only C, A and B, A and C, B and C, or A and B and C, wherein any such combination may contain one or more members of A, B, or C. A set should be interpreted as a collection of elements in which the number of elements is one or more. Therefore, for a set of X, X will include one or more elements. When at least one processor is configured to execute a set of functions, the at least one processor is configured to execute the set of functions individually or in any combination. Therefore, each processor in at least one processor can be configured to perform a specific subset of the set of functions, wherein the subset is the complete set, a suitable subset of the set, or an empty subset of the set. A processor may be referred to as a processor circuit. A memory / memory module may be referred to as a memory circuit. If a first device receives data from or sends data to a second device, data can be received / sent directly between the first and second devices, or indirectly between the first and second devices through a set of devices. A device configured to "output" or "provide" data (such as transmission, signaling, or messaging) may, for example, transmit data using a transceiver, or may transmit the data to the device that sent the data.A device configured to "acquire" data (such as, transmit, signal, or message) may, for example, receive the data using a transceiver, or may obtain the data from a device that receives the data. Information stored in memory includes instructions and / or data. All structural and functional equivalents of the elements throughout the various aspects described herein that are known to those skilled in the art or will later be known are expressly incorporated herein by reference and are covered by the claims. Furthermore, nothing disclosed herein is intended to be offered to the public, whether or not such disclosure is expressly recited in the claims. The words "module," "mechanism," "element," "device," etc., cannot replace the word "component." Therefore, no claim element will be construed as a functional component unless the element is expressly recited using the phrase "component for..."

[0183] As used in this article, the phrase “based on” should not be interpreted as referring to a closed set of information, one or more conditions, one or more factors, etc. In other words, the phrase “based on A” (where “A” can be information, conditions, factors, etc.) should be interpreted as “based on at least A”, unless specifically stated differently.

[0184] The following aspects are merely illustrative and may be combined with other aspects or teachings described herein without limitation.

[0185] Aspect 1 is a method for wireless communication at a UE. The method includes: obtaining channel information of a sidelink channel between the UE and a receiving device; performing a pre-equalization process on a signal to be transmitted to the receiving device based on the channel information to obtain a pre-equalized signal; and transmitting the pre-equalized signal to the receiving device through the sidelink channel.

[0186] Aspect 2 is the method according to aspect 1, wherein transmitting the pre-equalized signal comprises: transmitting the pre-equalized signal via a set of orthogonal frequency division multiplexing (OFDM) symbols using a sub-band full-duplex (SBFD) scheme or a frequency division duplex (FDD) scheme.

[0187] Aspect 3 is a method according to any one of Aspects 1 to 2, wherein the method further comprises: sending a pre-equalization indicator to the receiving device, the pre-equalization indicator instructing the receiving device to process the pre-equalized signal using a simplified receiving procedure, wherein the simplified receiving procedure skips the equalization process for the pre-equalized signal, and the pre-equalization indicator further comprises a method indicator indicating the pre-equalization process and side information for the simplified receiving procedure.

[0188] Aspect 4 is the method according to aspect 3, wherein the pre-equalization indicator is transmitted via one or more of the following: Radio Resource Control (RRC) configuration, Downlink Control Information (DCI), or Media Access Control (MAC) - Control Element (MAC-CE).

[0189] Aspect 5 is a method according to any one of aspects 1 to 3, wherein the method further comprises: receiving from the receiving device a receiver capability indicator indicating the receiving device's support for the pre-equalization process, and wherein performing the pre-equalization process comprises: performing the pre-equalization process in response to the receiver capability indicator.

[0190] Aspect 6 is a method according to any one of Aspects 1 to 2, wherein the method further comprises: transmitting a dedicated reference signal to the receiving device, wherein the channel information is based on the dedicated reference signal.

[0191] Aspect 7 is the method according to aspect 6, wherein the channel information includes receive (Rx) channel state information (CSI) associated with the sidelink channel.

[0192] Aspect 8 is the method according to aspect 7, wherein obtaining the channel information includes: receiving a set of received samples based on the dedicated reference signal from the receiving device; and identifying the Rx CSI associated with the sidelink channel based on the set of received samples.

[0193] Aspect 9 is the method according to aspect 7, wherein obtaining the channel information includes: receiving from the receiving device the Rx CSI associated with the sidelink channel, wherein the Rx CSI is based on the dedicated reference signal.

[0194] Aspect 10 is the method according to aspect 7, wherein the channel information further includes channel noise information, the channel noise information including a noise covariance matrix associated with the sidelink channel.

[0195] Aspect 11 is the method according to aspect 10, wherein obtaining the channel information further includes: receiving a set of received samples based on the dedicated reference signal from the receiving device; and identifying the channel noise information based on the set of received samples.

[0196] Aspect 12 is the method according to aspect 10, wherein obtaining the channel information further includes: receiving the channel noise information from the receiving device.

[0197] Aspect 13 is a method according to any one of Aspects 1 to 2, wherein the pre-equalization process includes a linear pre-equalization process, which includes one or more of the following: zero-forcing (ZF) pre-equalization, or minimum mean square error (MMSE) pre-equalization.

[0198] Aspect 14 is the method according to any one of Aspects 1 to 2, wherein the pre-equalization process includes a nonlinear pre-equalization process, the nonlinear pre-equalization process including one or more of the following: Thomlinson-Harashima (THP) zero-forcing (THP-ZF) pre-equalization, or THP-minimum mean square error (THP-MMSE) pre-equalization.

[0199] Aspect 15 is a method according to any one of Aspects 1 to 2, wherein the method further includes evaluating the validity of the channel information for performing the pre-equalization process, wherein performing the pre-equalization process includes: performing the pre-equalization process in response to the channel information being valid for performing the pre-equalization process, and wherein the method further includes: skipping the pre-equalization process for the signal in response to the channel information being invalid for performing the pre-equalization process; and transmitting the signal to the receiving device in response to the channel information being invalid for performing the pre-equalization process, so that the receiving device performs a regular equalization process on the signal.

[0200] Aspect 16 is a method according to any one of Aspects 1 to 15, wherein the method further comprises: receiving communication for the receiving device from a network entity, wherein the pre-equalization signal from the UE to the receiving device includes the communication for the receiving device from the network entity.

[0201] Aspect 17 is an apparatus for wireless communication at a UE, the apparatus comprising: a processing system including processor circuitry and memory circuitry storing code and coupled to the processor circuitry, the processing system being configured to cause the UE to perform one or more of the methods described in aspects 1 to 16.

[0202] Aspect 18 is an apparatus for wireless communication at a UE, the apparatus comprising: at least one memory; and at least one processor coupled to the at least one memory, wherein the at least one processor is configured individually or in any combination to perform the method according to any one of aspects 1 to 16.

[0203] Aspect 19 is an apparatus for wireless communication at a UE, the apparatus comprising components for performing each step of the method according to any one of aspects 1 to 16.

[0204] Aspect 20 is an apparatus according to any one of aspects 17 to 19, the apparatus further comprising a transceiver configured to receive or transmit in association with the method according to any one of aspects 1 to 16.

[0205] Aspect 21 is a computer-readable medium (e.g., a non-transitory computer-readable medium) storing computer-executable code at a UE, said code, when executed by at least one processor, causing said at least one processor to perform the method according to any one of aspects 1 to 16, either alone or in any combination.

[0206] Aspect 22 is a method for wireless communication at a receiving device. The method includes: receiving a dedicated reference signal from a user equipment (UE); transmitting channel information of a sidelink channel between the UE and the receiving device to the UE based on the dedicated reference signal; receiving a pre-equalized signal from the UE; and processing the pre-equalized signal using a simplified reception procedure, wherein the simplified reception procedure skips the equalization process for the pre-equalized signal.

[0207] Aspect 23 is the method according to aspect 22, wherein receiving the pre-equalized signal includes: receiving the pre-equalized signal via a set of orthogonal frequency division multiplexing (OFDM) symbols using a sub-band full-duplex (SBFD) scheme or a frequency division duplex (FDD) scheme.

[0208] Aspect 24 is a method according to any one of aspects 22 to 23, wherein the method further comprises: receiving from the UE a pre-equalization indicator indicating a simplified reception procedure for the pre-equalization signal, wherein the pre-equalization indicator further comprises a method indicator indicating a pre-equalization procedure performed on the pre-equalization signal and side information for the simplified reception procedure.

[0209] Aspect 25 is the method according to aspect 24, wherein the pre-equalization indicator is received via one or more of the following: Radio Resource Control (RRC) configuration, Downlink Control Information (DCI), or Media Access Control (MAC) - Control Element (MAC-CE).

[0210] Aspect 26 is the method according to aspect 24, wherein the method further includes: sending a receiver capability indicator to the UE indicating support for the pre-equalization process.

[0211] Aspect 27 is the method according to aspect 23, wherein the channel information includes receive (Rx) channel state information (CSI) associated with the sidelink channel.

[0212] Aspect 28 is the method according to aspect 27, wherein the method further includes: obtaining a set of received samples based on the dedicated reference signal, wherein transmitting the channel information includes: transmitting the set of received samples to the UE.

[0213] Aspect 29 is the method according to aspect 27, wherein the method further comprises: estimating the Rx CSI associated with the sidelink channel based on the dedicated reference signal, wherein transmitting the channel information comprises: transmitting the Rx CSI to the UE.

[0214] Aspect 30 is the method according to aspect 27, wherein the channel information further includes channel noise information, the channel noise information including a noise covariance matrix associated with the sidelink channel.

[0215] Aspect 31 is the method according to aspect 30, wherein the method further includes: estimating the channel noise information based on the dedicated reference signal.

[0216] Aspect 32 is an apparatus for wireless communication at a receiving device, the apparatus comprising: a processing system including processor circuitry and memory circuitry storing code and coupled to the processor circuitry, the processing system being configured to cause the receiving device to perform the method according to one or more of aspects 22 to 31.

[0217] Aspect 33 is an apparatus for wireless communication at a receiving device, the apparatus comprising: at least one memory; and at least one processor coupled to the at least one memory, wherein the at least one processor is configured individually or in any combination to perform the method according to any one of aspects 22 to 31.

[0218] Aspect 34 is an apparatus for wireless communication at a receiving device, the apparatus comprising components for performing each step of the method according to any one of aspects 22 to 31.

[0219] Aspect 35 is an apparatus according to any one of aspects 32 to 34, the apparatus further comprising a transceiver configured to receive or transmit in association with the method according to any one of aspects 22 to 31.

[0220] Aspect 36 is a computer-readable medium (e.g., a non-transitory computer-readable medium) storing computer-executable code at a receiving device, said code, when executed by at least one processor, causing said at least one processor to perform the method according to any one of aspects 22 to 31, either alone or in any combination.

Claims

1. An apparatus for wireless communication at a user equipment (UE), the apparatus comprising: At least one memory; and At least one processor, coupled to at least one memory, and configured individually or in any combination, based at least in part on information stored in the at least one memory, to cause the UE to: Obtain channel information of the sidelink channel between the UE and the receiving device; Based on the channel information, a pre-equalization process is performed on the signal to be sent to the receiving device to obtain a pre-equalized signal; as well as The pre-equalized signal is sent to the receiving device through the side link channel.

2. The apparatus according to claim 1, further comprising: A transceiver coupled to the at least one processor, wherein, in order to obtain the channel information, the at least one processor is configured individually or in any combination to obtain the channel information via the transceiver, and wherein, in order to transmit the pre-equalized signal, the at least one processor is configured individually or in combination to cause the UE to: The pre-equalized signal is transmitted using a sub-band full-duplex (SBFD) scheme or a frequency division duplex (FDD) scheme via a set of orthogonal frequency division multiplexing (OFDM) symbols.

3. The apparatus of claim 2, wherein the at least one processor is further configured, individually or in combination, to cause the UE to: A pre-equalization indicator is sent to the receiving device, the pre-equalization indicator instructing the receiving device to process the pre-equalized signal using a simplified receiving procedure, wherein the simplified receiving procedure skips the equalization process for the pre-equalized signal, and the pre-equalization indicator also includes a method indicator for the pre-equalization process and side information for the simplified receiving procedure.

4. The apparatus of claim 3, wherein the pre-equalization indicator is transmitted via one or more of the following: Radio Resource Control (RRC) configuration, Downlink Control Information (DCI), or Media Access Control (MAC) - Control Element (MAC-CE).

5. The apparatus of claim 3, wherein the at least one processor is further configured, individually or in combination, to cause the UE to: The receiving device receives a receiver capability indicator indicating the receiving device's support for the pre-equalization process, and wherein, in order to perform the pre-equalization process, the at least one processor is configured individually or in combination to cause the UE to: The pre-equalization process is performed in response to the receiver capability indicator.

6. The apparatus of claim 2, wherein the at least one processor is configured individually or in combination to cause the UE to: A dedicated reference signal is sent to the receiving device, wherein the channel information is based on the dedicated reference signal.

7. The apparatus of claim 6, wherein the channel information includes receive (Rx) channel state information (CSI) associated with the sidelink channel.

8. The apparatus of claim 7, wherein, in order to obtain the channel information, the at least one processor is configured individually or in combination to cause the UE to: Receive a set of received samples based on the dedicated reference signal from the receiving device; and The Rx CSI associated with the sidelink channel is identified based on the set of received samples.

9. The apparatus of claim 7, wherein, in order to obtain the channel information, the at least one processor is configured individually or in combination to cause the UE to: The receiving device receives the Rx CSI associated with the sidelink channel, wherein the Rx CSI is based on the dedicated reference signal.

10. The apparatus of claim 7, wherein the channel information further comprises channel noise information, the channel noise information comprising a noise covariance matrix associated with the sidelink channel.

11. The apparatus of claim 10, wherein, in order to obtain the channel information, the at least one processor is further configured, individually or in combination, to cause the UE to: Receive a set of received samples based on the dedicated reference signal from the receiving device; and The channel noise information is identified based on the set of received samples.

12. The apparatus of claim 10, wherein, in order to obtain the channel information, the at least one processor is further configured, individually or in combination, to cause the UE to: The channel noise information is received from the receiving device.

13. The apparatus of claim 2, wherein the pre-equalization process comprises a linear pre-equalization process, the linear pre-equalization process comprising one or more of the following: Zero-forcing (ZF) pre-equilibrium, or Minimum mean square error (MMSE) pre-equilibrium.

14. The apparatus of claim 2, wherein the pre-equalization process includes a nonlinear pre-equalization process, the nonlinear pre-equalization process including one or more of the following: Tomlinson-Harahima (THP) zero-forcing (THP-ZF) pre-equilibrium, or THP-Minimum Mean Square Error (THP-MMSE) pre-equilibration.

15. The apparatus of claim 2, wherein the at least one processor is further configured, individually or in combination, to cause the UE to: The effectiveness of the channel information used to perform the pre-equalization process is evaluated, wherein, in order to perform the pre-equalization process, the at least one processor is configured individually or in combination to cause the UE to: The pre-equalization process is performed in response to the channel information being valid for performing the pre-equalization process, and wherein the at least one processor is further configured, individually or in combination, to cause the UE to: In response to the channel information being invalid for performing the pre-equalization process, the pre-equalization process for the signal is skipped; and In response to the channel information being invalid for performing the pre-equalization process, the signal is sent to the receiving device so that the receiving device can perform a regular equalization process on the signal.

16. The apparatus of claim 1, wherein the at least one processor is further configured, individually or in combination, to cause the UE to: The communication received from the network entity for the receiving device includes the communication from the network entity for the receiving device.

17. An apparatus for wireless communication at a receiving device, the apparatus comprising: At least one memory; and At least one processor, coupled to the at least one memory, and configured individually or in any combination, based at least in part on information stored in the at least one memory, to enable the receiving device to: Receive dedicated reference signals from user equipment (UE); Based on the dedicated reference signal, channel information of the side link channel between the UE and the receiving device is sent to the UE; Receive the pre-equalized signal from the UE; as well as The pre-equalized signal is processed using a simplified receiving procedure, wherein the simplified receiving procedure skips the equalization process for the pre-equalized signal.

18. The apparatus of claim 17, further comprising: A transceiver coupled to the at least one processor, wherein, in order to receive the dedicated reference signal, the at least one processor is configured individually or in any combination to receive the dedicated reference signal via the transceiver, and wherein, in order to receive the pre-equalized signal, the at least one processor is configured individually or in combination to enable the receiving device to: The pre-equalized signal is received using a sub-band full-duplex (SBFD) scheme or a frequency division duplex (FDD) scheme via a set of orthogonal frequency division multiplexing (OFDM) symbols.

19. The apparatus of claim 18, wherein the at least one processor is configured individually or in combination to cause the receiving device to: The UE receives a pre-equalization indicator that indicates a simplified reception procedure for the pre-equalized signal, wherein the pre-equalization indicator further includes a method indicator indicating the pre-equalization procedure performed on the pre-equalized signal and side information for the simplified reception procedure.

20. The apparatus of claim 19, wherein the pre-equalization indicator is received via one or more of the following: Radio Resource Control (RRC) configuration, Downlink Control Information (DCI), or Media Access Control (MAC) - Control Element (MAC-CE).

21. The apparatus of claim 19, wherein the at least one processor is further configured, individually or in combination, to cause the receiving device to: Send a receiver capability indicator to the UE indicating support for the pre-equalization process.

22. The apparatus of claim 18, wherein the channel information includes receive (Rx) channel state information (CSI) associated with the sidelink channel.

23. The apparatus of claim 22, wherein the at least one processor is further configured, individually or in combination, to cause the receiving device to: A set of received samples is obtained based on the dedicated reference signal, wherein, in order to transmit the channel information, the at least one processor is configured individually or in combination to enable the receiving device to: The set of received samples is sent to the UE.

24. The apparatus of claim 22, wherein the at least one processor is configured individually or in combination to cause the receiving device to: The Rx CSI associated with the sidelink channel is estimated based on the dedicated reference signal, wherein, in order to transmit the channel information, the at least one processor is configured individually or in combination to cause the receiving device to: Send the Rx CSI to the UE.

25. The apparatus of claim 22, wherein the channel information further comprises channel noise information, the channel noise information comprising a noise covariance matrix associated with the sidelink channel.

26. The apparatus of claim 25, wherein the at least one processor is further configured, individually or in combination, to cause the receiving device to: The channel noise information is estimated based on the dedicated reference signal.

27. A method for conducting wireless communication at a user equipment (UE), the method comprising: Obtain channel information of the sidelink channel between the UE and the receiving device; Based on the channel information, a pre-equalization process is performed on the signal to be sent to the receiving device to obtain a pre-equalized signal; as well as The pre-equalized signal is sent to the receiving device through the side link channel.

28. The method of claim 27, wherein sending the pre-equalization signal comprises: The pre-equalized signal is transmitted using a sub-band full-duplex (SBFD) scheme or a frequency division duplex (FDD) scheme via a set of orthogonal frequency division multiplexing (OFDM) symbols.

29. A method for wireless communication at a receiving device, the method comprising: Receive dedicated reference signals from user equipment (UE); Based on the dedicated reference signal, channel information of the side link channel between the UE and the receiving device is sent to the UE; Receive the pre-equalized signal from the UE; as well as The pre-equalized signal is processed using a simplified receiving procedure, wherein the simplified receiving procedure skips the equalization process for the pre-equalized signal.

30. The method of claim 29, wherein receiving the pre-equalized signal comprises: The pre-equalized signal is received using a sub-band full-duplex (SBFD) scheme or a frequency division duplex (FDD) scheme via a set of orthogonal frequency division multiplexing (OFDM) symbols.

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