Ue with backscatter radio

Abstract

Apparatus, methods, and computer program products are included for backscatter communication (BC). An example method may include sending an indication of backscatter radio (BR) capability to a network entity. The example method may also include receiving, from the network entity, a first message indicating that the UE will remain in a master radio (MR) state or transition to a BR state.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims the benefit of U.S. non-provisional patent application serial number 17 / 664,624, filed on May 23, 2022, entitled “UE WITH BACKSCATTERING RADIO,” which is expressly incorporated herein by reference in its entirety. Technical Field

[0003] The present disclosure relates generally to communication systems, and more particularly to wireless communication systems having backscatter radio (BR). Background Art

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

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

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

[0007] In one aspect of the present disclosure, a method, a computer-readable medium, and an apparatus at a user equipment (UE) are provided. The apparatus may include a memory and at least one processor coupled to the memory. The memory and the at least one processor coupled to the memory may be configured to send an indication of backscatter radio (BR) capabilities to a network entity. The memory and the at least one processor coupled to the memory may be further configured to receive a first message from the network entity indicating that the UE will remain in a primary radio (MR) state or transition to a BR state.

[0008] In another aspect of the present disclosure, a method, a computer-readable medium, and an apparatus at a network entity are provided. The apparatus may include a memory and at least one processor coupled to the memory. The memory and the at least one processor coupled to the memory may be configured to receive an indication of a backscatter radio (BR) capability associated with a user equipment (UE). The memory and the at least one processor coupled to the memory may be further configured to send a first message to the UE, the first message indicating that the UE will remain in a primary radio (MR) state or transition to a BR state.

[0009] To achieve the aforementioned and related purposes, one or more aspects include the features fully described below and particularly pointed out in the claims. The following description and the accompanying drawings set forth in detail some exemplary features of one or more aspects. However, these features are only indicative of only some of the various ways in which the principles of the various aspects can be employed. BRIEF DESCRIPTION OF THE DRAWINGS

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

[0011] Figure 2A is a diagram illustrating an example of a first frame according to various aspects of the present disclosure.

[0012] Figure 2B is a diagram illustrating an example of DL channels within a subframe according to various aspects of the present disclosure.

[0013] Figure 2C is a diagram illustrating an example of a second frame according to various aspects of the present disclosure.

[0014] Figure 2D is a diagram illustrating an example of UL channels within a subframe according to various aspects of the present disclosure.

[0015] Figure 3 is a diagram illustrating an example of a base station and a user equipment (UE) in an access network.

[0016] Figure 4 is a diagram illustrating an example radio frequency identification (RFID).

[0017] Figure 5 is a diagram illustrating an example passive device in communication with a network entity.

[0018] Figure 6 is a diagram illustrating an example low power wake-up radio (LP-WUR) receiver and a main radio (MR).

[0019] Figure 7 is a diagram illustrating example communications between network entities and a UE.

[0020] Fig. 8A is a diagram illustrating example communications using a BR and waking up an MR.

[0021] Figure 8B is a diagram illustrating example communications using a BR and waking up an MR.

[0022] Fig. 9 is a flow chart of a method of wireless communication.

[0023] Fig.10 is a flow chart of a method of wireless communication.

[0024] Fig.11 is a flow chart of a method of wireless communication.

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

[0026] Fig.13 are diagrams illustrating examples of hardware implementations of example devices and / or network entities.

[0027] Fig.14 is a diagram illustrating an example of a hardware implementation of an example network entity. DETAILED DESCRIPTION

[0028] The detailed description set forth below in conjunction with the accompanying drawings is a description of various configurations and does not represent the only configurations with which the concepts described herein can be practiced. In order to provide a thorough understanding of the various concepts, the specific embodiments include specific details. However, these concepts can be practiced without these specific details. In some cases, well-known structures and components are shown in block diagram form to avoid blurring these concepts.

[0029] Several aspects of telecommunication systems are presented with reference to various apparatus and methods. These apparatus and methods are described in the following detailed description and illustrated in the accompanying drawings by various blocks, components, circuits, processes, algorithms, etc. (collectively referred to as "elements"). These elements may be implemented using electronic hardware, computer software, or any combination thereof. Whether these elements are implemented as hardware or software depends on the specific application and the design constraints imposed on the overall system.

[0030] For example, an element, or any part of an element, or any combination of elements can be implemented as a "processing system", which includes one or more processors. Examples of processors include microprocessors, microcontrollers, graphics processing units (GPUs), central processing units (CPUs), application processors, digital signal processors (DSPs), reduced instruction set computing (RISC) processors, systems on chip (SoCs), baseband processors, field programmable gate arrays (FPGAs), programmable logic devices (PLDs), state machines, gating logic, discrete hardware circuits, and other suitable hardware configured to perform various functionalities described in this disclosure. One or more processors in a processing system can execute software. Whether referred to as software, firmware, middleware, microcode, hardware description language, or other terms, software should be broadly interpreted as meaning instructions, instruction sets, codes, code segments, program codes, programs, subroutines, software components, applications, software applications, software packages, routines, subroutines, objects, executable files, threads of execution, procedures, functions, or any combination thereof.

[0031] Therefore, in one or more example aspects, specific implementations and / or use cases, the described functions may be implemented with hardware, software, or any combination thereof. If implemented in software, the functions may be stored or encoded as one or more instructions or codes on a computer-readable medium. Computer-readable media include computer storage media. Storage media may be any available medium that can be accessed by 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 disk storage, magnetic disk storage, other magnetic storage devices, combinations of these types of computer-readable media, or any other medium that can be used to store computer-executable code in the form of instructions or data structures that can be accessed by a computer.

[0032] Although various aspects, specific implementations and / or use cases are described in this application by the illustration of some examples, additional or different aspects, specific implementations and use cases may be generated in many different arrangements and scenarios. The various aspects, specific implementations and / or use cases described herein can be implemented across many different platform types, devices, systems, shapes, sizes and packaging arrangements. For example, various aspects, specific implementations and / or use cases can be generated via integrated chip specific implementations and other devices based on non-module components (e.g., end-user devices, vehicles, communication equipment, computing equipment, industrial equipment, retail / purchase equipment, medical equipment, devices that enable artificial intelligence (AI), etc.). Although some examples may or may not be specifically for use cases or applications, the described examples may have wide applicability. Various aspects, specific implementations and / or use cases can be in the range from chip-level or modular components to non-modular, non-chip-level specific implementations, and further to the range of aggregated, distributed or original equipment manufacturer (OEM) equipment or systems in conjunction with one or more technologies herein. In some actual settings, the equipment combined with the various aspects and features described may also include additional components and features for implementing and practicing the claimed and described aspects. For example, the transmission and reception of wireless signals necessarily include several components for analog and digital purposes (e.g., hardware components including antennas, RF chains, power amplifiers, modulators, buffers, processors, interleavers, adders / summers, etc.) The techniques described herein can be practiced in a wide variety of devices of various sizes, shapes, and configurations, chip-level components, systems, distributed arrangements, clustered or disaggregated components, end-user devices, etc.

[0033] The deployment of a communication system (such as a 5G NR system) can be arranged with various components or components in a variety of ways. In a 5G NR system or network, a network node, a network entity, a mobility element of a network, a radio access network (RAN) node, a core network node, a network element or a network equipment (such as a base station (BS) or one or more units (or one or more components) that perform base station functionality) can be implemented in a clustered or decomposed architecture. For example, a BS (such as a Node B (NB), an evolved NB (eNB), an NR BS, a 5G NB, an access point (AP), a transmit receive point (TRP) or a cell, etc.) can be implemented as a clustered base station (also referred to as an independent BS or a monolithic BS) or a decomposed base station.

[0034] A clustered base station may be configured to utilize a radio protocol stack physically or logically integrated within a single RAN node. A decomposed base station may be configured to utilize a protocol stack physically or logically distributed between two or more units, such as one or more central or centralized units (CUs), one or more distributed units (DUs), or one or more radio units (RUs). In some aspects, a CU may be implemented within a RAN node, and one or more DUs may be co-located with the CU, or alternatively, may be geographically or virtually distributed in one or more other RAN nodes. A DU may be implemented to communicate with one or more RUs. Each of a CU, a DU, and a RU may be implemented as a virtual unit, i.e., a virtual central unit (VCU), a virtual distributed unit (VDU), or a virtual radio unit (VRU).

[0035] Base station operation or network design may take into account the aggregated nature of base station functionality. For example, a disaggregated base station may be used in an integrated access backhaul (IAB) network, an open radio access network (O-RAN (network configuration such as that initiated by the O-RAN Alliance)), or a virtualized radio access network (vRAN, also known as a cloud radio access network (C-RAN)). Decomposition may include distributing functionality across two or more units at various physical locations, as well as virtually distributing functionality of at least one unit, which may enable flexibility in network design. Individual units of a disaggregated base station or disaggregated RAN architecture may be configured for wired or wireless communication with at least one other unit.

[0036] Figure 1 1 is a diagram 100 illustrating an example of a wireless communication system and an access network. The illustrated wireless communication system includes a disaggregated base station architecture. The disaggregated base station architecture may include one or more CUs 110 that may communicate directly with a core network 120 via a backhaul link, or indirectly with the core network 120 through one or more disaggregated base station units, such as a near real-time (near RT) RAN intelligent controller (RIC) 125 via an E2 link, or a non-real-time (non-RT) RIC 115 associated with a service management and orchestration (SMO) framework 105, or both. The CU 110 may communicate with one or more DUs 130 via corresponding midhaul links, such as an F1 interface. The DU 130 may communicate with one or more RUs 140 via corresponding fronthaul links. The RU 140 may communicate with corresponding UEs 104 via one or more radio frequency (RF) access links. In some implementations, a UE 104 may be served simultaneously by multiple RUs 140.

[0037] Each of the units (i.e., CU 110, DU 130, RU 140, and near-RT RIC 125, non-RT RIC 115, and SMO framework 105) may include or be coupled to one or more interfaces configured to receive or transmit signals, data, or information (collectively, signals) via a wired or wireless transmission medium. Each of the units or an associated processor or controller that provides instructions to the communication interface of the unit may be configured to communicate with one or more of the other units via a transmission medium. For example, the units may include a wired interface configured to receive signals or transmit signals to one or more of the other units via a wired transmission medium. Additionally, the units may include a wireless interface that may include a receiver, transmitter, or transceiver (such as an RF transceiver) configured to receive signals or transmit signals to one or more of the other units via a wireless transmission medium, or both.

[0038] In some aspects, CU 110 may host one or more higher layer control functions. Such control functions may include radio resource control (RRC), packet data convergence protocol (PDCP), service data adaptation protocol (SDAP), etc. Each control function may be implemented using an interface configured to communicate signals with other control functions hosted by CU 110. CU110 may be configured to handle user plane functionality (i.e., central unit-user plane (CU-UP)), control plane functionality (i.e., central unit-control plane (CU-CP)), or a combination thereof. In some specific implementations, CU 110 may be logically split into one or more CU-UP units and one or more CU-CP units. When implemented in an O-RAN configuration, the CU-UP unit may communicate bidirectionally with the CU-CP unit via an interface (such as an E1 interface). As needed, CU 110 may be implemented to communicate with DU 130 for network control and signaling.

[0039] DU 130 may correspond to a logical unit that includes one or more base station functions for controlling the operation of one or more RUs 140. In some aspects, DU 130 may host one or more of a radio link control (RLC) layer, a medium access control (MAC) layer, and one or more high physical (PHY) layers (such as modules for forward error correction (FEC) encoding and decoding, scrambling, modulation and demodulation, etc.) at least in part according to a functional split such as those defined by 3GPP. In some aspects, DU 130 may also host one or more low PHY layers. Each layer (or module) may be implemented using an interface that is configured to communicate signals with other layers (and modules) hosted by DU 130 or with control functions hosted by CU 110.

[0040] The lower layer functionality may be implemented by one or more RUs 140. In some deployments, the RU 140 controlled by the DU 130 may correspond to a logical node that hosts RF processing functions or low PHY layer functions (such as performing fast Fourier transform (FFT), inverse FFT (iFFT), digital beamforming, physical random access channel (PRACH) extraction and filtering, etc.), or both, based at least in part on functional splitting (such as lower layer functional splitting). In such an architecture, the RU 140 may be implemented to handle over-the-air (OTA) communications with one or more UEs 104. In some specific implementations, 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 may enable the implementation of the DU 130 and the CU 110 in a cloud-based RAN architecture (such as a vRAN architecture).

[0041] The SMO framework 105 may be configured to support RAN deployment and provisioning of non-virtualized network elements and virtualized network elements. For non-virtualized network elements, the SMO framework 105 may be configured to support the deployment of dedicated physical resources for RAN coverage requirements, which may be managed via an operation and maintenance interface (such as an O1 interface). For virtualized network elements, the SMO framework 105 may be configured to interact with a cloud computing platform (such as an open cloud (O-Cloud) 190) to perform network element lifecycle management (such as instantiating virtualized network elements) via a cloud computing platform interface (such as an O2 interface). Such virtualized network elements may include, but are not limited to, CU 110, DU 130, RU 140, and near-RT RIC 125. In some specific implementations, the SMO framework 105 may communicate with hardware aspects of the 4G RAN (such as an open eNB (O-eNB) 111) via the O1 interface. Additionally, in some specific implementations, the SMO framework 105 may communicate directly with one or more RUs 140 via the O1 interface. The SMO framework 105 may also include a non-RT RIC 115 configured to support the functionality of the SMO framework 105 .

[0042] The non-RT RIC 115 may be configured to include logic functions that enable non-real-time control and optimization of RAN elements and resources, artificial intelligence (AI) / machine learning (ML) (AI / ML) workflows including model training and updating, or policy-based guidance of applications / features in the near-RT RIC 125. The non-RT RIC 115 may be coupled to or in communication with the near-RT RIC 125 (such as via an A1 interface). The near-RT RIC 125 may be configured to include logic functions that enable near-real-time control and optimization of RAN elements and resources via data collection and actions through an interface (such as via an E2 interface) that connects one or more CUs 110, one or more DUs 130, or both, and the O-eNB with the near-RT RIC 125.

[0043] In some implementations, in order to generate an AI / ML model to be deployed in the near-RT RIC 125, the non-RT RIC 115 may receive parameters or external enrichment information from an external server. Such information may be utilized by the near-RT RIC 125 and may be received from a non-network data source or from a network function at the SMO framework 105 or the non-RT RIC 115. In some examples, the non-RT RIC 115 or the near-RT RIC 125 may be configured to tune RAN behavior or performance. For example, the non-RT RIC 115 may monitor long-term trends and patterns of performance and employ AI / ML models to perform corrective actions through the SMO framework 105 (such as via reconfiguration of O1) or via the creation of RAN management policies (such as A1 policies).

[0044] At least one of the CU 110, the DU 130, and the RU 140 may be referred to as a base station 102. Therefore, the base station 102 may include one or more of the CU 110, the DU 130, and the RU 140 (each component is indicated by a dotted line to indicate that each component may be included in the base station 102 or may not be included in the base station). The base station 102 provides an access point to the core network 120 for the UE 104. The base station 102 may include a macro cell (a high-power cellular base station) and / or a small cell (a low-power cellular base station). Small cells include femto cells, pico cells, and micro cells. A network including both small cells and macro cells may be referred to as a heterogeneous network. A heterogeneous network may also include a home evolved Node B (eNB) (HeNB), which may provide services to a restricted group referred to as a closed subscriber group (CSG). The communication link between RU 140 and UE 104 may include uplink (UL) (also known as reverse link) transmission from UE 104 to RU 140 and / or downlink (DL) (also known as forward link) transmission from RU 140 to UE 104. The communication link may use multiple-input multiple-output (MIMO) antenna technology, including spatial multiplexing, beamforming and / or transmit diversity. The communication link may be through one or more carriers. For each carrier allocated in a carrier aggregation of up to Yx MHz (x component carriers) for transmission in each direction, the base station 102 / UE 104 may use a spectrum of up to Y MHz (e.g., 5MHz, 10MHz, 15MHz, 20MHz, 100MHz, 400MHz, etc.) bandwidth. The carriers may or may not be adjacent to each other. The allocation of carriers may be asymmetric with respect to DL and UL (e.g., more or fewer carriers may be allocated to DL compared to UL). The component carrier may include a primary component carrier and one or more secondary component carriers. The primary component carrier may be referred to as a primary cell (PCell), and the secondary component carrier may be referred to as a secondary cell (SCell).

[0045] Some UEs 104 may communicate with each other using a device-to-device (D2D) communication link 158. The D2D communication link 158 may use DL / UL wireless wide area network (WWAN) spectrum. The D2D communication link 158 may use one or more sidelink channels, such as a physical sidelink broadcast channel (PSBCH), a physical sidelink discovery channel (PSDCH), a physical sidelink shared channel (PSSCH), and a physical sidelink control channel (PSCCH). The D2D communication may be through a variety of wireless D2D communication systems, such as, for example, Bluetooth, Wi-Fi based on the Institute of Electrical and Electronics Engineers (IEEE) 802.11 standard, LTE, or NR.

[0046] The wireless communication system may also include a Wi-Fi AP 150 that communicates with a UE 104 (also referred to as a Wi-Fi station (STA)) via a communication link 154, for example, in a 5 GHz unlicensed spectrum, etc. When communicating in an unlicensed spectrum, the UE 104 / AP 150 may perform a clear channel assessment (CCA) to determine whether a channel is available prior to communication.

[0047] 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 identified as frequency range designations FR1 (410 MHz-7.125 GHz) and FR2 (24.25 GHz-52.6 GHz). Although a portion of FR1 is greater than 6 GHz, FR1 is often (interchangeably) referred to as the "sub-6 GHz" band in various documents and articles. A similar naming issue sometimes occurs with respect to FR2, which is often (interchangeably) referred to as the "millimeter wave" band in documents and articles, although different from the extremely high frequency (EHF) band (30 GHz-300 GHz) identified as the "millimeter wave" band by the International Telecommunication Union (ITU).

[0048] Frequencies between FR1 and FR2 are generally referred to as mid-band frequencies. Recent 5G NR research has identified the operating bands for these mid-band frequencies as frequency range designation FR3 (7.125GHz-24.25GHz). The bands falling within FR3 can inherit FR1 characteristics and / or FR2 characteristics, and therefore the features of FR1 and / or FR2 can be effectively extended to mid-band frequencies. In addition, higher frequency bands are currently being explored to extend 5G NR operations to more than 52.6GHz. For example, three higher operating bands have been identified as frequency range designations FR2-2 (52.6GHz-71GHz), FR4 (71GHz-114.25GHz) and FR5 (114.25GHz-300GHz). Each of these higher frequency bands falls within the EHF band.

[0049] In view of the above, unless otherwise specified, if the term "6 GHz or less" is used herein, it may broadly refer to frequencies that may be less than 6 GHz, may be within FR1, or may include mid-band frequencies. In addition, unless otherwise specified, if the term "millimeter wave" is used herein, it may broadly refer to frequencies that may include mid-band frequencies, may be within FR2, FR4, FR2-2, and / or FR5, or may be within the EHF band.

[0050] The base station 102 and the UE 104 may each include multiple antennas (such as antenna elements, antenna panels, and / or antenna arrays) to facilitate beamforming. The base station 102 may send a beamformed signal 182 to the UE 104 in one or more transmit directions. The UE 104 may receive the beamformed signal from the base station 102 in one or more receive directions. The UE 104 may also send a beamformed signal 184 to the base station 102 in one or more transmit directions. The base station 102 may receive the beamformed signal from the UE 104 in one or more receive directions. The base station 102 / UE 104 may perform beam training to determine the best receive direction and transmit direction for each of the base station 102 / UE 104. The transmit direction and receive direction of the base station 102 may be the same or different. The transmit direction and receive direction of the UE 104 may be the same or different.

[0051] The base station 102 may include and / or be referred to as a gNB, a Node B, an eNB, an access point, a base transceiver station, a radio base station, a radio transceiver, a transceiver function, a basic service set (BSS), an extended service set (ESS), a TRP, a network node, a network entity, a network equipment, or some other suitable term. The base station 102 may be implemented as an integrated access and backhaul (IAB) node, a relay node, a sidelink node, a clustered (monolithic) base station with a baseband unit (BBU) (including a CU and a DU) and a RU, or as a disaggregated base station including one or more of a CU, a DU, and / or a RU.

[0052] The core network 120 may include an access and mobility management function (AMF) 161, a session management function (SMF) 162, a user plane function (UPF) 163, a unified data management (UDM) 164, one or more location servers 168, and other functional entities. AMF 161 is a control node that handles signaling between UE 104 and the core network 120. AMF 161 supports registration management, connection management, mobility management, and other functions. SMF 162 supports session management and other functions. UPF 163 supports packet routing, packet forwarding, and other functions. UDM 164 supports the generation of authentication and key agreement (AKA) credentials, user identity handling, access authorization, and subscription management. One or more location servers 168 are illustrated as including a gateway mobile location center (GMLC) 165 and a location management function (LMF) 166. However, in general, the one or more location servers 168 may include one or more location / positioning servers, which may include one or more of the GMLC 165, LMF 166, positioning determination entity (PDE), serving mobile location center (SMLC), mobile positioning center (MPC), etc. GMLC 165 and LMF 166 support UE location services. GMLC 165 provides an interface for clients / applications (e.g., emergency services) to access UE positioning information. LMF 166 receives measurement and assistance information from NG-RAN and UE 104 via AMF 161 to calculate the positioning of UE 104. NG-RAN may determine the positioning of UE 104 using one or more positioning methods. Positioning UE 104 may involve signal measurements, position estimation, and optional speed calculations based on these measurements. Signal measurements may be performed by UE 104 and / or serving base station 102. The measured signals may be based on a satellite positioning system (SPS) 170 (e.g., one or more of a global navigation satellite system (GNSS), a global positioning system (GPS), a non-terrestrial network (NTN), or other satellite positioning / location systems), LTE signals, wireless local area network (WLAN) signals, Bluetooth signals, a terrestrial beacon system (TBS), sensor-based information (e.g., an atmospheric pressure sensor, a motion sensor), an NR enhanced cell ID (NR E-CID) method, NR signals (e.g., multi-round trip time (multi-RTT), DL angle of departure (DL-AoD), DL time difference of arrival (DL-TDOA), UL time difference of arrival (UL-TDOA), and UL angle of arrival (UL-AoA) positioning), and / or one or more of other systems / signals / sensors.

[0053] Examples of UE 104 include cellular phones, smart phones, session initiation protocol (SIP) phones, laptops, personal digital assistants (PDAs), satellite radios, global positioning systems, multimedia devices, video devices, digital audio players (e.g., MP3 players), cameras, game consoles, tablet devices, smart devices, wearable devices, vehicles, electric meters, gas pumps, large or small kitchen appliances, healthcare equipment, implants, sensors / actuators, displays, or any other similarly functional devices. Some of the UEs 104 may be referred to as IoT devices (e.g., parking meters, gas pumps, toasters, vehicles, heart monitors, etc.). UE 104 may also be referred to as stations, mobile stations, subscriber stations, mobile units, subscriber units, wireless units, remote units, mobile devices, wireless devices, wireless communication devices, remote devices, mobile subscriber stations, access terminals, mobile terminals, wireless terminals, remote terminals, mobile phones, user agents, mobile clients, clients, or some other suitable terminology. In some scenarios, the term UE may also be applied to one or more supporting devices, such as in a device cluster arrangement. One or more of these devices may access the network collectively and / or individually.

[0054] Reference again Figure 1 In some aspects, the UE 104 may include a BC component 198. In some aspects, the BC component 198 may be configured to send an indication of backscatter radio (BR) capability to a network entity. In some aspects, the BC component 198 may be further configured to receive a first message from the network entity indicating that the UE will remain in a primary radio (MR) state or transition to a BR state.

[0055] In certain aspects, the base station 102 may include a BC component 199. In some aspects, the BC component 199 may be configured to receive an indication of a BR capability associated with the UE. In some aspects, the BC component 199 may be further configured to send a first message to the UE indicating that the UE will remain in the MR state or transition to the BR state.

[0056] Although the following description may focus on 5G NR, the concepts described herein may be applicable to other similar areas such as LTE, LTE-A, CDMA, GSM, and other wireless technologies.

[0057] As described herein, a node (which may be referred to as a node, a network node, a network entity, or a wireless node) may include, may be, or may be included in (e.g., as a component of) a base station (e.g., any base station described herein), a UE (e.g., any UE described herein), a network controller, an apparatus, a device, a computing system, an integrated access and backhaul (IAB) node, a distributed unit (DU), a central unit (CU), a remote unit (RU), and / or another processing entity configured to perform any of the techniques described herein. For example, the network node may be a UE. For another example, the network node may be a base station or a network entity. For another example, a first network node may be configured to communicate with a second network node or a third network node. In one aspect of this example, the first network node may be a UE, the second network node may be a base station, and the third network node may be a UE. In another aspect of this example, the first network node may be a UE, the second network node may be a base station, and the third network node may be a base station. In yet other aspects of this example, the first network node, the second network node, and the third network node may be different relative to these examples. Similarly, references to UE, base station, device, equipment, computing system, etc. may include disclosure of UE, base station, device, equipment, computing system, etc. as a network node. For example, a disclosure that a UE is configured to receive information from a base station also discloses that a first network node is configured to receive information from a second network node. Consistent with the present disclosure, once a specific example is expanded according to the present disclosure (e.g., a UE is configured to receive information from a base station also discloses that a first network node is configured to receive information from a second network node), a broader example of a narrower example may be interpreted in reverse, but in a broad, open-ended manner. In the above example where a UE is configured to receive information from a base station also discloses that a first network node is configured to receive information from a second network node, the first network node may refer to a first UE configured to receive information, a first base station, a first device, a first device, a first computing system, a first group of one or more components, a first processing entity, etc.; and the second network node may refer to a second UE, a second base station, a second device, a second device, a second computing system, a second group of one or more components, a second processing entity, etc.

[0058] As described herein, different terms may be used in various aspects to describe the communication of information (e.g., any information, signal, etc.). Disclosure of one communication term includes disclosure of other communication terms. For example, a first network node may be described as being configured to send information to a second network node. In this example and consistent with the present disclosure, disclosure that the first network node is configured to send information to the second network node includes disclosure that the first network node is configured to provide, transmit, output, communicate, or send information to the second network node. Similarly, in this example and consistent with the present disclosure, disclosure that the first network node is configured to send information to the second network node includes disclosure that the second network node is configured to receive, obtain, or decode information provided, transmitted, output, communicated, or sent by the first network node.

[0059] Figure 2A FIG200 is a diagram illustrating an example of a first subframe within a 5G NR frame structure. Figure 2B FIG230 is a diagram illustrating an example of DL channels within a 5G NR subframe. Figure 2C FIG250 is a diagram illustrating an example of a second subframe within a 5G NR frame structure. Figure 2D FIG280 is a diagram illustrating an example of UL channels within a 5G NR subframe. The 5G NR frame structure may be frequency division duplex (FDD), where for a particular set of subcarriers (carrier system bandwidth), subframes within that subcarrier set are dedicated to either DL or UL, or may be time division duplex (TDD), where for a particular set of subcarriers (carrier system bandwidth), subframes within that subcarrier set are dedicated to both DL and UL. Figure 2A , Figure 2C In the example provided, the 5G NR frame structure is assumed to be TDD, where subframe 4 is configured with slot format 28 (most of which are DL), where D is DL, U is UL, and F is flexible between DL / UL, and subframe 3 is configured with slot format 1 (all of which are UL). Although subframes 3 and 4 are shown as having slot formats 1 and 28, respectively, any particular subframe may be configured with any of the various available slot formats 0-61. Slot formats 0 and 1 are all DL and all UL, respectively. Other slot formats 2-61 include a mix of DL, UL, and flexible symbols. The slot format is configured for the UE via a received slot format indicator (SFI) (dynamically configured via DL control information (DCI) or semi-statically / statically configured via radio resource control (RRC) signaling).

[0060] FIG. 2A to FIG. 2DThe frame structure is illustrated, and various aspects of the present disclosure may be applicable to other wireless communication technologies that may have different frame structures and / or different channels. A frame (10ms) may be divided into 10 subframes of equal size (1ms). Each subframe may include one or more time slots. A subframe may also include a microslot, which may include 7, 4, or 2 symbols. Each time slot may include 14 or 12 symbols, depending on whether the cyclic prefix (CP) is normal or extended. For a normal CP, each time slot may include 14 symbols, and for an extended CP, each time slot may include 12 symbols. The symbol on the DL may be a CP orthogonal frequency division multiplexing (OFDM) (CP-OFDM) symbol. The symbol on the UL may be a CP-OFDM symbol (for high throughput scenarios) or a discrete Fourier transform (DFT) extended OFDM (DFT-s-OFDM) symbol (also known as a single carrier frequency division multiple access (SC-FDMA) symbol) (for power-limited scenarios; limited to single-stream transmission). The number of slots within a subframe is based on the CP and the parameter set. The parameter set defines the subcarrier spacing (SCS) and effectively defines the symbol length / duration, which is equal to 1 / SCS.

[0061]

[0062] For normal CP (14 symbols / slot), different parameter sets μ0 to 4 allow 1, 2, 4, 8, and 16 slots per subframe, respectively. For extended CP, parameter set 2 allows 4 slots per subframe. Thus, for normal CP and parameter set μ, there are 14 symbols / slot and 2 μ timeslots / subframe. The subcarrier spacing can be equal to 2 μ *15kHz, where μ is parameter set 0 to 4. Therefore, parameter set μ=0 has a subcarrier spacing of 15kHz, and parameter set μ=4 has a subcarrier spacing of 240kHz. The symbol length / duration is inversely related to the subcarrier spacing. FIG. 2A to FIG. 2D An example of a parameter set μ=2 with a normal CP of 14 symbols per slot and 4 slots per subframe is provided. The slot duration is 0.25 ms, the subcarrier spacing is 60 kHz, and the symbol duration is about 16.67 μs. Within a frame set, there may be one or more different bandwidth parts (BWPs) that are frequency-division multiplexed (see Figure 2B ). Each BWP may have a specific parameter set and CP (normal or extended).

[0063] A resource grid may be used to represent the frame structure. Each slot includes a resource block (RB) (also called a physical RB (PRB)) extending over 12 consecutive subcarriers. The resource grid is divided into a number of resource elements (REs). The number of bits carried by each RE depends on the modulation scheme.

[0064] like Figure 2A As illustrated, some of the REs carry reference (pilot) signals (RS) for the UE. The RS may include a demodulation RS (DM-RS) (indicated as R for one particular configuration, but other DM-RS configurations are possible) and a channel state information reference signal (CSI-RS) for channel estimation at the UE. The RS may also include a beam measurement RS (BRS), a beam refinement RS (BRRS), and a phase tracking RS (PT-RS).

[0065] Figure 2B Examples of various DL channels within a subframe of a frame are illustrated. A physical downlink control channel (PDCCH) carries DCI within one or more control channel elements (CCEs) (e.g., 1, 2, 4, 8, or 16 CCEs), each CCE including six RE groups (REGs), each REG including 12 consecutive REs in an OFDM symbol of an RB. A PDCCH within a BWP may be referred to as a control resource set (CORESET). The UE is configured to monitor PDCCH candidates in a PDCCH search space (e.g., a common search space, a UE-specific search space) during a PDCCH monitoring opportunity on a CORESET, wherein the PDCCH candidates have different DCI formats and different aggregation levels. Additional BWPs may be located at higher and / or lower frequencies on the channel bandwidth. A primary synchronization signal (PSS) may be within symbol 2 of a particular subframe of a frame. The PSS is used by UE 104 to determine subframe / symbol timing and physical layer identification. A secondary synchronization signal (SSS) may be within symbol 4 of a particular subframe of a frame. The SSS is used by the UE to determine the physical layer cell identity group number and the radio frame timing. Based on the physical layer identity and the physical layer cell identity group number, the UE can determine the physical cell identifier (PCI). Based on the PCI, the UE can determine the location of the DM-RS. The physical broadcast channel (PBCH) carrying the master information block (MIB) can be logically grouped with the PSS and SSS to form a synchronization signal (SS) / PBCH block (also called SS block (SSB)). The MIB provides the number of RBs in the system bandwidth and the system frame number (SFN). The physical downlink shared channel (PDSCH) carries user data, broadcast system information not sent via the PBCH (such as the system information block (SIB)), and paging messages.

[0066] like Figure 2CAs illustrated, some of the REs carry DM-RS (indicated as R for a particular configuration, but other DM-RS configurations are possible) for channel estimation at the base station. The UE may send a DM-RS for a physical uplink control channel (PUCCH) and a DM-RS for a physical uplink shared channel (PUSCH). The PUSCH DM-RS may be sent in the first or first two symbols of the PUSCH. Depending on whether a short PUCCH or a long PUCCH is sent and depending on the specific PUCCH format used, the PUCCH DM-RS can be sent in different configurations. The UE may send a sounding reference signal (SRS). The SRS may be sent in the last symbol of a subframe. The SRS may have a comb structure, and the UE may send the SRS on one of the combs in the comb. The SRS may be used by the base station for channel quality estimation to achieve frequency-dependent scheduling of the UL.

[0067] Figure 2D Examples of various UL channels within a subframe of a frame are illustrated. The PUCCH may be located at a position as indicated in one configuration. The PUCCH carries uplink control information (UCI), such as scheduling requests, channel quality indicators (CQI), precoding matrix indicators (PMI), rank indicators (RI), and hybrid automatic repeat request (HARQ) acknowledgement (ACK) (HARQ-ACK) feedback (i.e., one or more HARQ ACK bits indicating one or more ACKs and / or negative ACKs (NACKs)). The PUSCH carries data and may additionally be used to carry a buffer status report (BSR), a power headroom report (PHR), and / or UCI.

[0068] Figure 3375. The Controller / Processor 375 is a block diagram of a base station 310 communicating with a UE 350 in an access network. In the DL, Internet Protocol (IP) packets may be provided to a controller / processor 375. The controller / processor 375 implements layer 3 and layer 2 functionality. Layer 3 includes a radio resource control (RRC) layer, and layer 2 includes a service data adaptation protocol (SDAP) layer, a packet data convergence protocol (PDCP) layer, a radio link control (RLC) layer, and a medium access control (MAC) layer. The controller / processor 375 provides RRC layer functionality associated with broadcasting of system information (e.g., MIB, SIB), RRC connection control (e.g., RRC connection paging, RRC connection establishment, RRC connection modification, and RRC connection release), inter-radio access technology (RAT) mobility, and measurement configuration for UE measurement reporting; PDCP layer functionality associated with header compression / decompression, security (encryption, decryption, integrity protection, integrity verification), and handover support functions; RLC layer functionality associated with delivery of upper layer packet data units (PDUs), error correction through ARQ, concatenation, segmentation and reassembly of RLC service data units (SDUs), re-segmentation of RLC data PDUs, and reordering of RLC data PDUs; and MAC layer functionality associated with mapping between logical channels and transport channels, multiplexing of MAC SDUs onto transport blocks (TBs), demultiplexing of MAC SDUs from TBs, scheduling information reporting, error correction through HARQ, priority handling, and logical channel prioritization.

[0069] The transmit (TX) processor 316 and receive (RX) processor 370 implement layer 1 functionality associated with various signal processing functions. Layer 1 (which includes the physical (PHY) layer) may include error detection on the transport channel, forward error correction (FEC) coding / decoding of the transport channel, interleaving, rate matching, mapping to the physical channel, modulation / demodulation of the physical channel, and MIMO antenna processing. The TX processor 316 handles the mapping to the signal constellation based on various modulation schemes (e.g., binary phase shift keying (BPSK), quadrature phase shift keying (QPSK), M-order phase shift keying (M-PSK), M-order quadrature amplitude modulation (M-QAM)). The coded and modulated symbols can then be divided into parallel streams. Each stream can then be mapped to an OFDM subcarrier, multiplexed with a reference signal (e.g., pilot) in the time and / or frequency domain, and then combined using an inverse fast Fourier transform (IFFT) to produce a physical channel carrying a time domain OFDM symbol stream. The OFDM stream is spatially precoded to generate multiple spatial streams. Channel estimates from a channel estimator 374 may be used to determine the coding and modulation schemes, as well as for spatial processing. Channel estimates may be derived from reference signals and / or channel state feedback sent by the UE 350. Each spatial stream may then be provided to a different antenna 320 via a separate transmitter 318Tx. Each transmitter 318Tx may modulate a radio frequency (RF) carrier with a corresponding spatial stream for transmission.

[0070] At the UE 350, each receiver 354Rx receives a signal through its corresponding antenna 352. Each receiver 354Rx recovers the information modulated onto the RF carrier and provides the information to a receive (RX) processor 356. The TX processor 368 and the RX processor 356 implement layer 1 functionality associated with various signal processing functions. The RX processor 356 can perform spatial processing on the information to recover any spatial stream destined for the UE 350. If multiple spatial streams are destined for the UE 350, they can be combined into a single OFDM symbol stream by the RX processor 356. The RX processor 356 then converts the OFDM symbol stream from the time domain to the frequency domain using a fast Fourier transform (FFT). The frequency domain signal includes a separate OFDM symbol stream for each subcarrier of the OFDM signal. The reference signal and the symbol on each subcarrier are recovered and demodulated by determining the signal constellation point most likely to be sent by the base station 310. These soft decisions can be based on channel estimates calculated by the channel estimator 358. The soft decisions are then decoded and deinterleaved to recover the data and control signals originally sent on the physical channel by the base station 310. The data and control signals are then provided to the controller / processor 359, which implements layer 3 and layer 2 functionality.

[0071] The controller / processor 359 may be associated with a memory 360 that stores program codes and data. The memory 360 may be referred to as a computer-readable medium. In the UL, the controller / processor 359 provides demultiplexing between transport channels and logical channels, packet reassembly, decryption, header decompression, and control signal processing to recover IP packets. The controller / processor 359 is also responsible for error detection using ACK and / or NACK protocols to support HARQ operations.

[0072] Similar to the functionality described in conjunction with DL transmissions performed by the base station 310, the controller / processor 359 provides RRC layer functionality associated with system information (e.g., MIB, SIB) acquisition, RRC connection, and measurement reporting; PDCP layer functionality associated with header compression / decompression and security (encryption, decryption, integrity protection, integrity verification); RLC layer functionality associated with delivery of upper layer PDUs, error correction through ARQ, concatenation, segmentation and reassembly of RLC SDUs, resegmentation of RLC data PDUs, and reordering of RLC data PDUs; and MAC layer functionality associated with mapping between logical channels and transport channels, multiplexing of MAC SDUs onto TBs, demultiplexing of MAC SDUs from TBs, scheduling information reporting, error correction through HARQ, priority handling, and logical channel prioritization.

[0073] Channel estimates derived by the channel estimator 358 from a reference signal or feedback sent by the base station 310 may be used by the TX processor 368 to select the appropriate coding and modulation schemes and to facilitate spatial processing. The spatial streams generated by the TX processor 368 may be provided to different antennas 352 via corresponding transmitters 354Tx. Each transmitter 354Tx may modulate an RF carrier with a corresponding spatial stream for transmission.

[0074] UL transmissions are processed at the base station 310 in a manner similar to that described in conjunction with the receiver functionality at the UE 350. Each receiver 318Rx receives a signal through its corresponding antenna 320. Each receiver 318Rx recovers information modulated onto an RF carrier and provides the information to the RX processor 370.

[0075] The controller / processor 375 may be associated with a memory 376 that stores program codes and data. The memory 376 may be referred to as a computer readable medium. In the UL, the controller / processor 375 provides demultiplexing between transport channels and logical channels, packet reassembly, decryption, header decompression, control signal processing to recover IP packets. The controller / processor 375 is also responsible for error detection using ACK and / or NACK protocols to support HARQ operations.

[0076] At least one of the TX processor 368, the RX processor 356, and the controller / processor 359 may be configured to combine Figure 1 The BC component 198 is used to perform various aspects.

[0077] At least one of the TX processor 316, the RX processor 370, and the controller / processor 375 may be configured to combine Figure 1 BC Component 199 is used to perform various aspects.

[0078] In addition to devices with higher capabilities, wireless communications may also support devices with reduced capabilities (RedCap). In other examples, examples of devices with higher capabilities include advanced smart phones, V2X devices, URLLC devices, eMBB devices, etc. In other examples, devices with reduced capabilities may include wearable devices (e.g., such as smart watches, augmented reality glasses, virtual reality glasses, health and medical monitoring devices, etc.), industrial wireless sensor networks (IWSNs) (e.g., such as pressure sensors, humidity sensors, motion sensors, thermal sensors, accelerometers, actuators, etc.), surveillance cameras, low-end smart phones, etc. For example, the NR communication system may support both devices with higher capabilities and devices with reduced capabilities. Devices with reduced capabilities may be referred to as NR light devices, low-layer devices, lower-layer devices, etc. UEs with reduced capabilities may communicate based on various types of wireless communications. For example, smart wearable devices may send or receive communications based on low power wide area networks (LPWA) / mMTC, loose IoT devices may send or receive communications based on URLLC, sensors / cameras may send or receive communications based on eMBB, and the like.

[0079] In addition to devices with reduced capabilities, devices with lower capabilities than devices with reduced capabilities, including lower power consumption and less complex structures, may also be included in the wireless communication system. In some wireless communication systems, passive wireless devices (such as zero-power passive IoT wireless devices) may be included. Such passive wireless devices may not have active RF components, and may perform transmission based on backscatter communication, and may perform reception based on envelope detection or envelope detectors. Backscatter communication can modulate information on an incoming RF signal (which may be a carrier that can carry communications between other devices) by adapting the antenna load impedance. Passive wireless devices may be battery-free or battery-assisted. For example, a passive wireless device may operate based on energy harvesting from incoming radio waves with or without a battery as an additional power source. Passive wireless devices may have low power consumption, such as between 1 microwatt and 1000 microwatts. Such passive wireless devices may be devices for inventory management, wireless sensors, etc. Passive devices may use backscatter communication to communicate with another network entity (such as a base station).

[0080] Backscatter communication can realize radio frequency identification (RFID). For example, a reader can transmit a continuous waveform signal and an inquiry command. An RF tag (which is a passive wireless device) can harvest energy from a continuous waveform signal and can respond to inquiries by changing its input impedance (e.g., between a conjugate match and a strong mismatch), thereby modulating the backscatter signal. RFID is a rapidly developing technology that affects many industries due to its potential for inventory / asset management inside and outside warehouses, IoT, sustainable sensor networks in factories and / or agriculture, and smart homes. RFID may include a small transponder that transmits an information-bearing signal when a signal is received, which may be referred to as a tag. RFID can operate with low operating expenditure (OPEX) without a battery and can use a small amount of resources. RFID can use less maintenance and can have a long life cycle. Figure 4 4 is a diagram illustrating an example RFID. Figure 4 As illustrated, an RFID reader 402 may transmit an energy signal 406 to a passive device, such as an RFID tag 404. The RFID tag 404 may harvest the energy signal 406 in the air and power the transmit / receive circuitry on the RFID tag 404. By harvesting the energy signal 406, the RFID tag 404 may transmit a signal 408 that may be backscatter modulated. In some aspects, semi-passive or active RFID may be used instead of passive RFID.

[0081] Figure 5 5 is a diagram illustrating an example passive device communicating with a network entity. Figure 5 As illustrated, in some aspects, the network entity 506 may transmit energy signals to one or more passive devices 502 and receive backscattered modulated information signals from the one or more passive devices 502. To efficiently support passive devices in many use cases (e.g., asset management, logistics, warehousing, and manufacturing), in some aspects, the network entity 506 may read / write information stored on the one or more passive devices 502, provide energy to the one or more passive devices 502, receive information-bearing signals (e.g., based on harvesting energy and reflected backscattered modulated signals from signals transmitted by the network entity 506), and read reflected information-bearing signals to decode information transmitted by the one or more passive devices 502.

[0082] Figure 6600 is a diagram illustrating an example low power wake-up radio (LP-WUR) receiver and a main radio (MR). The LP-WUR 604 is a companion receiver that monitors a wake-up signal (WUS) at very low power when the MR 606 is in a deep sleep state. The LP-WUR 604 may wake up the main radio when data communication may occur. For example, the LP-WUR 604 may monitor for WUS at opportunity 662. Based on the absence of receiving the WUS, the MR 606 may not wake up at opportunity 652. The LP-WUR 604 may monitor for WUS at opportunity 664. Based on the receipt of the WUS, the MR 606 may wake up at opportunity 654. The LP-WUR 604 may consume low power and may be powered separately from the MR 606. The LP-WUR 604 may not be used for two-way communication with a network entity (such as a base station) and may be used to monitor paging information so that the MR 606 may be woken up for communication.

[0083] In some aspects, to further reduce the energy consumed (eg, transition energy used to wake up the MR), in some aspects, backscatter radio (BR) may be used instead of LP-WUR.

[0084] Figure 7 700 is a diagram illustrating an example communication between a network entity 704 and a UE 702. In some aspects, the network entity 704 may be referred to as a network node. In some aspects, the network node may be implemented as a converged base station, a component of a decomposed base station, an integrated access and backhaul (IAB) node, a relay node, a sidelink node, etc. In some aspects, the network entity 704 may be implemented in a converged or monolithic base station architecture, or alternatively in a decomposed base station architecture, and may include one or more of a CU, a DU, a RU, a near real-time (near-RT) RAN intelligent controller (RIC), or a non-real-time (non-RT) RIC.

[0085] In some aspects, UE 702 may include MR 756 and BR 754 with LP-WUR. In some aspects, BR 754 may be used to receive and send data. In some aspects, BR 754 with LP-WUR may be ultra-low power, with passive components for both receiving and sending, thereby achieving a longer sleep time for MR. In some aspects, the state of UE 702 in which MR 756 is asleep (and MR 756 is not sending or receiving data) may be referred to as a "BR state". In some aspects, the state of UE 702 in which MR 756 is awake (for sending or receiving data) may be referred to as a "MR state". By using BR 754, low data rate communication using BR 754 may be possible, thereby achieving lower latency for low data rate data transmission (because it may take time to wake up MR 756 for low data rate data transmission). Based on the various aspects described herein, BR 754 with LP-WUR may wake up MR 756 in different situations.

[0086] In some aspects, the BR 754 may include a transceiver with envelope detection based reception. In some aspects, the transceiver may not have an LNA low noise amplifier and may use a power amplifier (PA). In some aspects, the transceiver may use load modulation based transmission, for example, absorbing or reflecting an incoming EM wave (which may be otherwise referred to as a "carrier"). In some aspects, the transceiver included as part of the BR 754 may be associated with integrated circuit (IC) support for processing UL and DL data (e.g., reading memory, calculating cyclic redundancy check (CRC), waking up MR or staying in BR, etc.). In some aspects, the BR 754 may be equipped with power harvesting circuitry that enables wireless power harvesting in idle mode and charges the battery.

[0087] like Figure 7As illustrated, the UE 702 may report BR capability 708 to the network entity 704. The term "BR capability" may refer to a capability associated with using BR instead of MR for communication (such as receiving / transmitting) with a base station. In some aspects, the network entity 704 may announce (e.g., in a MIB / SIB) in an announcement 706 that backscatter communication (BC) is supported or not supported; one or more bits in the MIB / SIB may indicate the cell's support for BC. In some aspects, the BR capability 708 may be reported based on the announcement 706 indicating support for BC by the network entity 704. In some aspects, a BC configuration 709 may be sent to the UE 702 using broadcast or dedicated signaling (e.g., BC-BWP). In some aspects, the BC configuration 709 may be sent to the UE 702 based on receiving the BR capability 708. In some aspects, the UE 702 may send a request 710 to request a transition to a BR state. For example, the UE 702 may determine a deep sleep opportunity based on traffic arrival (e.g., downlink traffic pattern), battery status, etc., and send a request 710 accordingly. In some aspects, the request 710 may be a message request to transition to a BR state to save power. In some aspects, the request 710 may also indicate the UE 702's recommendation for a minimum BR duration, a transition time to a wake-up MR, etc.

[0088] In some aspects, the network entity 704 may send an indication 711 to the UE 702 indicating to enter sleep (transition to BR state) or remain in MR. At 712, the UE 702 may accordingly transition to the BR state (e.g., put the MR 756 into sleep state) or remain in MR 756 (MR 756 remains active). In some aspects, the indication 711 may be sent in response to the request 710. In some aspects, the network entity 704 may determine that the UE 702 may transition to the BR state based on the request 710 of the UE 702 (e.g., and associated downlink traffic pattern, power state, etc.), and accordingly send the indication 711 indicating to enter sleep (transition to BR state). In some aspects, the network entity 704 may configure (e.g., as part of the indication 711) a monitoring opportunity for the UE 702 (e.g., such as the BR 754) to monitor a paging signal or WUS, so that the UE 702 may wake up the MR 756 based on the signaling from the network entity 704. In some aspects, the network entity 704 may configure (e.g., as part of the indication 711) an UL triggering opportunity for the UE 702 to send a radio transition signal indicating that the UE 702 wants to wake up the MR 756 based on UL traffic that may not be efficiently sent using the BR 754 (e.g., a UL packet size exceeding a threshold).

[0089] In some aspects, the network entity 704 may send an indication 711 indicating to enter sleep (transition to BR state) without receiving the request 710, based on the load of the cell and the capabilities of one or more UEs in the area associated with the network entity 704. In some aspects, the network entity 704 may receive a response from the UE 702 indicating whether the UE 702 may transition to the BR state (e.g., determined based on a UL buffer at the UE 702, which may represent UL packets to be sent by the UE 702). If the UL buffer at the UE 702 is greater than a threshold, the UE 702 may respond by not transitioning to the BR state. If the UL buffer at the UE 702 is less than a threshold, the UE 702 may respond by transitioning to the BR state.

[0090] In some aspects, after the UE 702 remains in the MR state or transitions to the BR state at 712, the UE 702 and the network entity 704 may exchange communications 714. In some aspects, if the UE 702 remains in the MR state, the UE 702 may exchange communications 714 using the BR 754. For example, the UE 702 may backscatter a waveform (which may otherwise be referred to as a "carrier") sent by the network entity 704 by absorbing / reflecting an indicator bit in the carrier. In some aspects, communications based on the BR 754 may have a smaller range than communications based on the MR 756.

[0091] In some aspects, the BR 754 may be powered by the network entity 704. For example, the BR 754 may be passive, and the UE 702 may indicate to the network entity 704 that the BR 754 may operate based on the transmission energy of the network entity 704 (e.g., energy in a carrier) without other power sources. In some aspects, the network entity 704 may send one or more sounding signals 716. In some aspects, the one or more sounding signals 716 may be sent before the UE 702 transitions to the BR state (puts the MR 756 in a sleep state). In some aspects, the one or more sounding signals 716 may be sent after the UE 702 transitions to the BR state (puts the MR 756 in a sleep state). In some aspects, the term "sounding signal" may refer to a signal (such as a pulse signal) sent by a network entity to check for operations associated with a BR on a UE. The sounding signal may be a continuous "carrier" of beamforming that provides energy to one UE or a group of UEs. The UE may provide feedback so that the network entity may select a transmit beam based on the feedback; the sounding signal may be a power-optimized waveform in which an energy signal is transmitted at a favorable frequency, power level, and shape (e.g., a pulse with a high peak or a continuous wave); similarly, a power-optimized waveform may be selected based on UE feedback.

[0092] In some aspects, upon receiving the one or more sounding signals 716, the UE 702 may provide feedback to the network entity 704, such as measurements 718. The measurements 718 may represent BR measurements and may represent whether the coverage from the network entity 704 (based on the transmit energy associated with the one or more sounding signals 716) may be sufficient for the UE 702 to operate in a BR state (using BR 754). In some aspects, the network entity 704 may adjust (such as increase) transmit power or adjust precoding / beams used to transmit carriers to the BR 754 based on the measurements 718 (e.g., at 722). In some aspects, after adjusting the transmit power or adjusting the precoding / beams (e.g., at 722), the UE 702 and the network entity 704 may further exchange communications 724.

[0093] In some aspects, the UE 702 or the network entity 704 may determine whether the BR 754 powered by the network entity 704 is sufficient, for example, using a UE-side measurement 718 of the BR exceeding an input power threshold (which may be determined by the network entity 704 based on UE-BR sensitivity plus a shadow margin) may indicate that the BR 754 powered by the network entity 704 is sufficient. In some aspects, using a UE-side measurement 718 of the BR not exceeding an input power threshold (which may be determined by the network entity 704 based on UE-BR sensitivity plus a shadow margin) may indicate that the BR 754 powered by the network entity 704 is not sufficient. In some aspects, if the BR 754 cannot be powered by the network entity 704, the UE 702 may also be configured (such as by the network entity 704 in an indication 711 or separate signaling) with periodic occasions for waking up the MR 756. In some aspects, the network entity 704 may power up the BR 754 at one or more occasions (which may be referred to as "check BR" occasions) by transmitting a carrier 726. In some aspects, one or more of the opportunities (and the time for transmitting the carrier 726) may be earlier than the opportunity to wake up the MR (associated with waking up the MR 756) by T1, where T1 may be a time and may be based on the time taken to wake up the MR 756. In some aspects, if the BR 754 cannot be powered up by the carrier 726 at 728, the UE 702 may wake up the MR 756 (and switch to the MR state) at 732.

[0094] Fig. 8A FIG. 8 is a diagram illustrating an example communication using a BR and waking up a MR. Fig. 8AAs illustrated, the UE 702 may perform BR measurements and provide feedback at 802, which may correspond to receiving the sounding signal 716 and sending the measurement 718. In some aspects, the UE 702 may also communicate with the network entity 704 at 804, which may correspond to communication 724. In some aspects, at the check BR ​​opportunity 806, which may correspond to receiving the carrier 726, the UE 702 may determine that the BR 754 is not powered and accordingly wake up at the WU-MR opportunity 808, which may be T1 after the check BR ​​opportunity 806.

[0095] In some aspects, the BR 754 may be powered by a battery at the UE 702. For example, the BR 754 may be semi-passive, and the UE 702 may indicate to the network entity 704 that the BR 754 may operate based on the transmit energy of the network entity 704 (e.g., energy in the carrier) and the battery. In some aspects, the network entity 704 may send one or more sounding signals 716. In some aspects, the one or more sounding signals 716 may be sent before the UE 702 transitions to the BR state (putting the MR 756 in the sleep state). In some aspects, the one or more sounding signals 716 may be sent after the UE 702 transitions to the BR state (putting the MR 756 in the sleep state).

[0096] In some aspects, upon receiving the one or more sounding signals 716, the UE 702 may provide feedback to the network entity 704, such as measurement 718. The measurement 718 may represent a BR measurement and may represent whether the coverage from the network entity 704 (based on the transmit energy associated with the one or more sounding signals 716) may be sufficient for the UE 702 to operate in a BR state (using the BR 754, which may be semi-passive and powered by both battery and carrier energy). In some aspects, the network entity 704 may adjust (such as increase) the transmit power or adjust the precoding / beam used to transmit the carrier to the BR 754 based on the measurement 718 (e.g., at 722). In some aspects, after adjusting the transmit power or adjusting the precoding / beam (e.g., at 722), the UE 702 and the network entity 704 may further exchange communications 724. In some aspects, the UE 702 may also adjust the PA to adjust the BC based on the measurement 718 at 720. In some aspects, the information may be sent to or by the UE 702 using the BR 754. In some aspects, the data size may be small, such as less than 1,000 bits. In some aspects, the UE 702 may use the BR 754 to perform a CRC without forward error correction (FEC) for the BC when the MR 756 is asleep.

[0097] In some aspects, if the network entity 704 can page the UE 702, the network entity 704 can send the WUS 730 to the UE 702. For example, the WUS 730 can be based on information associated with a buffer at the network entity 704, which can buffer data for the UE 702. For example, if the data is associated with a voice call, associated with a payload size above a threshold, or associated with a high reliability low latency specification, the WUS 730 can be sent. After receiving the WUS 730, the UE 702 can wake up the MR 756 at 732 accordingly.

[0098] Figure 8B 850 is a diagram illustrating an example communication using a BR and waking up a MR. Figure 8B As illustrated, the UE 702 may perform BR measurements and provide feedback at 852, which may correspond to receiving the sounding signal 716 and sending the measurement 718. In some aspects, the UE 702 may also communicate with the network entity 704 at 854, which may correspond to the communication 724. In some aspects, upon receiving the WUS 856, which may correspond to the WUS 730, the UE 702 may wake up at the WU-MR opportunity 858.

[0099] Fig. 9 900 is a flow chart of a method of wireless communication. The method may be performed by a UE (eg, UE 104, UE 702; device 1304).

[0100] At 902, the UE may send an indication of BR capability to a network entity. For example, UE 702 may send an indication of BR capability to network entity 704 (eg, 706). In some aspects, 902 may be performed by BC component 198.

[0101] At 904, the UE may receive a first message from the network entity indicating that the UE will remain in the MR state or transition to the BR state. For example, the UE 702 may receive a first message (e.g., 711) from the network entity 704 indicating that the UE will remain in the MR state or transition to the BR state. In some aspects, 904 may be performed by the BC component 198.

[0102] Fig.10 1000 is a flow chart of a method of wireless communication. The method may be performed by a UE (eg, UE 104, UE 702; device 1304).

[0103] In some aspects, at 1001, the UE may receive a notification indicating support for BC from a network entity, wherein the indication of BR capability is sent based on the notification. For example, the UE 702 may receive a notification 706 indicating support for BC from the network entity 704, wherein the indication of BR capability is sent based on the notification. In some aspects, 1001 may be performed by the BC component 198.

[0104] At 1002, the UE may send an indication of BR capability to a network entity. For example, the UE 702 may send an indication of BR capability to the network entity 704 (eg, 706). In some aspects, 1002 may be performed by the BC component 198.

[0105] At 1003, the UE may send a second message to the network entity, wherein the second message may indicate a request to transition from the MR state to the BR state. For example, the UE 702 may send a second message to the network entity, wherein the second message may indicate a request 710 to transition from the MR state to the BR state. In some aspects, 1003 may be performed by the BC component 198.

[0106] At 1004, the UE may receive a first message from a network entity indicating that the UE will remain in the MR state or transition to the BR state. For example, the UE 702 may receive a first message (e.g., 711) from the network entity 704 indicating that the UE will remain in the MR state or transition to the BR state. In some aspects, 1004 may be performed by the BC component 198. In some aspects, the first message may be based on the second message and the downlink traffic mode associated with the UE. In some aspects, the first message may be received before sending the second message. In some aspects, the second message may be sent before receiving the first message. In some aspects, the second message may indicate a minimum duration associated with the BR state or a transition time to wake-up. In some aspects, the second message may be based on at least one of a traffic arrival or a battery state.

[0107] At 1006, the UE may remain in the MR state or transition to the BR state based on the first message. For example, the UE 702 may remain in the MR state or transition to the BR state based on the first message (e.g., at 712). In some aspects, 1006 may be performed by the BC component 198.

[0108] At 1007, the UE may receive a third message from the network entity, wherein the third message indicates that the UE will transition from the MR state to the BR state. For example, the UE 702 may receive a third message (such as WUS 730) from the network entity, wherein the third message indicates that the UE will transition from the MR state to the BR state. In some aspects, 1007 may be performed by the BC component 198.

[0109] At 1008, the UE may communicate with the network entity based on remaining in the MR state or transitioning to the BR state, wherein the communication with the network entity may be based on the received first message. For example, the UE 702 may communicate (e.g., 714 or 724) with the network entity 704 based on remaining in the MR state or transitioning to the BR state, wherein the communication with the network entity is based on the received first message. In some aspects, 1008 may be performed by the BC component 198. In some aspects, the communication is based on transitioning to the BR state, wherein the BR state is based on a passive BR and is powered by a first carrier associated with the network entity, and the UE may receive one or more sounding signals 716 from the network entity 704 before transitioning to the BR state, and send measurements 718 associated with the one or more sounding signals before transitioning to the BR state or after transitioning to the BR state.

[0110] In some aspects, at 1032, the UE may receive a second carrier for powering the passive BR at a first opportunity before a second opportunity, wherein the second opportunity is configured for transitioning back to the MR state. For example, the UE 702 may receive a second carrier (e.g., 726) for powering the passive BR at a first opportunity (e.g., 806) before a second opportunity (e.g., 808), wherein the second opportunity may be configured for transitioning back to the MR state. In some aspects, 1032 may be performed by the BC component 198.

[0111] In some aspects, at 1034, the UE may transition back to the MR state based on a failure to power the passive BR from the second carrier. For example, the UE 702 may transition back to the MR state (e.g., at 732) based on a failure to power the passive BR from the second carrier (e.g., at 728). In some aspects, 1034 may be performed by the BC component 198.

[0112] In some aspects, the communication may be based on transitioning to a BR state, wherein the BR state is based on a semi-passive BR and is powered by a battery associated with the UE. At 1012, the UE may receive one or more sounding signals from a network entity before transitioning to the BR state. For example, the UE 702 may receive one or more sounding signals 716 from the network entity 704 before transitioning to the BR state. In some aspects, 1012 may be performed by the BC component 198.

[0113] At 1014, the UE may send measurements associated with one or more sounding signals before transitioning to the BR state or after transitioning to the BR state. For example, the UE 702 may send measurements associated with one or more sounding signals 718 before transitioning to the BR state or after transitioning to the BR state. In some aspects, 1014 may be performed by the BC component 198.

[0114] At 1020, the UE may adjust a power amplifier (PA) associated with the UE based on the measurement. For example, UE 702 may adjust a PA associated with UE 702 based on measurement 718 (eg, at 720). In some aspects, 1020 may be performed by BC component 198.

[0115] At 1022, the UE may receive a WUS from the network entity, wherein the WUS indicates transitioning back to the MR state. For example, the UE 702 may receive a WUS 730 from the network entity 704, wherein the WUS may indicate transitioning back to the MR state (e.g., at 732). In some aspects, 1022 may be performed by the BC component 198.

[0116] Fig.11 1100 is a flow chart of a method of wireless communication. The method may be performed by a network entity (eg, base station 102, network entity 704, network entity 1302, network entity 1402).

[0117] At 1102, a network entity may receive an indication of BR capabilities associated with a UE. For example, the network entity 704 may receive an indication of BR capabilities (eg, 708) associated with the UE 702. In some aspects, 1102 may be performed by the BC component 199.

[0118] At 1104, the network entity may send a first message to the UE, the first message indicating that the UE will remain in the MR state or transition to the BR state. For example, the network entity 704 may send a first message (e.g., 711) to the UE 702, the first message indicating that the UE will remain in the MR state or transition to the BR state. In some aspects, 1104 may be performed by the BC component 199.

[0119] Fig.12 1200 is a flow chart of a method of wireless communication. The method may be performed by a network entity (eg, base station 102, network entity 704, network entity 1302, network entity 1402).

[0120] At 1201, a network entity may send an advertisement indicating support for backscatter communication (BC), wherein the indication of BR capability is received based on the advertisement. For example, the network entity 704 may send an advertisement 706 indicating support for backscatter communication (BC), wherein the indication of BR capability is received based on the advertisement. In some aspects, 1201 may be performed by the BC component 199.

[0121] At 1202, a network entity may receive an indication of BR capabilities associated with a UE. For example, the network entity 704 may receive an indication of BR capabilities (eg, 708) associated with the UE 702. In some aspects, 1202 may be performed by the BC component 199.

[0122] At 1203, the network entity may receive a second message from the UE, wherein the second message indicates a request to transition from the MR state to the BR state. For example, the network entity 704 may receive a second message from the UE, wherein the second message indicates a request 710 to transition from the MR state to the BR state. In some aspects, 1203 may be performed by the BC component 199.

[0123] At 1204, the network entity may send a first message to the UE, indicating that the UE will remain in the MR state or transition to the BR state. For example, the network entity 704 may send a first message (e.g., 711) to the UE 702, indicating that the UE will remain in the MR state or transition to the BR state. In some aspects, 1204 may be performed by the BC component 199. In some aspects, the first message may be based on the second message and the downlink traffic mode associated with the UE. In some aspects, the first message may be sent before receiving the second message. In some aspects, the second message may be received before sending the first message. In some aspects, the second message may also indicate the minimum duration associated with the BR state or the transition time to wake-up. In some aspects, the second message may be based on at least one of the traffic arrival or the battery state.

[0124] At 1207, the network entity may send a third message to the UE, wherein the third message indicates that the UE will transition from the MR state to the BR state. For example, the network entity 704 may send a third message (e.g., WUS 730) to the UE 702, wherein the third message indicates that the UE will transition from the MR state to the BR state. In some aspects, 1207 may be performed by the BC component 199.

[0125] At 1208, the network entity may communicate with the UE based on the MR state or the BR state, wherein the communication with the UE is based on the first message sent. For example, the network entity 704 may communicate with the UE 702 based on the MR state or the BR state (e.g., 714 or 724), wherein the communication with the UE is based on the first message sent. In some aspects, 1208 may be performed by the BC component 199. In some aspects, the communication may be based on the BR state, wherein the BR state may be based on a passive BR and powered by a first carrier associated with the network entity. At 1212, the network entity may send one or more sounding signals to the UE. For example, the network entity 704 may send one or more sounding signals 716 to the UE 702. In some aspects, 1212 may be performed by the BC component 199. At 1214, the network entity may receive measurements associated with the one or more sounding signals from the UE. For example, the network entity 704 may receive measurements 718 associated with the one or more sounding signals 716 from the UE 702. In some aspects, 1214 may be performed by the BC component 199. At 1220 , the network entity may adjust the power of the first carrier based on the measurement. For example, the network entity 704 may adjust the power of the first carrier based on the measurement (eg, at 722 ). In some aspects, 1220 may be performed by the BC component 199 .

[0126] In some aspects, at 1234, the network entity may transmit a second carrier for powering the passive BR at a first opportunity before a second opportunity, wherein the second opportunity is configured for the MR state. For example, the network entity 704 may transmit a second carrier (e.g., 726) for powering the passive BR at a first opportunity before a second opportunity, wherein the second opportunity is configured for the MR state. In some aspects, 1234 may be performed by the BC component 199.

[0127] In some aspects, the communication may be based on a BR state, wherein the BR state may be based on a semi-passive BR and powered by a battery associated with the UE. At 1212, the network entity may send one or more sounding signals to the UE. For example, the network entity 704 may send one or more sounding signals 716 to the UE 702. In some aspects, 1212 may be performed by the BC component 199. At 1214, the network entity may receive measurements associated with the one or more sounding signals from the UE. For example, the network entity 704 may receive measurements 718 associated with the one or more sounding signals 716 from the UE 702. In some aspects, 1214 may be performed by the BC component 199. At 1220, the network entity may adjust the power of the first carrier based on the measurement. For example, the network entity 704 may adjust the power of the first carrier based on the measurement (e.g., at 722). In some aspects, 1220 may be performed by the BC component 199.

[0128] At 1222, the network entity may send a wake-up signal (WUS) to the UE, wherein the WUS may indicate a transition back to the MR state. For example, the network entity 704 may send the WUS 730 to the UE 702, wherein the WUS indicates a transition back to the MR state. In some aspects, 1222 may be performed by the BC component 199.

[0129] Fig.131300 is an example of a hardware implementation of an example device 1304. The device 1304 may be a UE, a component of a UE, or may implement UE functionality. In some aspects, the device 1304 may include a cellular baseband processor 1324 (also referred to as a modem) coupled to one or more transceivers 1322 (e.g., a cellular RF transceiver). The cellular baseband processor 1324 may include on-chip memory 1324'. In some aspects, the device 1304 may also include one or more subscriber identity module (SIM) cards 1320 and an application processor 1306 coupled to a secure digital (SD) card 1308 and a screen 1310. The application processor 1306 may include on-chip memory 1306'. In some aspects, the device 1304 may also include a Bluetooth module 1312, a WLAN module 1314, a satellite system module 1316 (e.g., a GNSS module), one or more sensor modules 1318 (e.g., an atmospheric pressure sensor / altimeter; a motion sensor such as an inertial management unit (IMU), a gyroscope, and / or an accelerometer; light detection and ranging (LIDAR), radio-aided detection and ranging (RADAR), sound navigation and ranging (SONAR), a magnetometer, audio, and / or other technologies for positioning), an additional memory module 1326, a power source 1330, and / or a camera 1332. The Bluetooth module 1312, the WLAN module 1314, and the satellite system module 1316 may include an on-chip transceiver (TRX) / receiver (RX). The cellular baseband processor 1324 communicates with the UE 104 and / or with a RU associated with the network entity 1302 through the transceiver 1322 via one or more antennas 1380. The cellular baseband processor 1324 and the application processor 1306 may each include a computer-readable medium / memory 1324', 1306', respectively. The additional memory module 1326 may also be considered a computer-readable medium / memory. Each computer-readable medium / memory 1324', 1306', 1326 may be non-transitory. The cellular baseband processor 1324 and the application processor 1306 are each responsible for general processing, including executing software stored on a computer-readable medium / memory. The software, when executed by the cellular baseband processor 1324 / application processor 1306, enables the cellular baseband processor 1324 / application processor 1306 to perform various functions described herein. The computer-readable medium / memory may also be used to store data manipulated by the cellular baseband processor 1324 / application processor 1306 when executing the software. The cellular baseband processor 1324 / application processor 1306 may be a component of the UE 350 and may include at least one of the memory 360 and / or the TX processor 368, the RX processor 356, and the controller / processor 359.In one configuration, the device 1304 may be a processor chip (modem and / or applications) and include only the cellular baseband processor 1324 and / or the application processor 1306, while in another configuration, the device 1304 may be an entire UE (eg, see. Figure 3 350) and includes additional modules of device 1304.

[0130] As discussed herein, in some aspects, the BC component 198 may be configured to send an indication of backscatter radio (BR) capability to a network entity. In some aspects, the BC component 198 may be further configured to receive a first message from the network entity indicating that the UE will remain in the master radio (MR) state or transition to the BR state. The BC component 198 may be within the cellular baseband processor 1324, within the application processor 1306, or within both the cellular baseband processor 1324 and the application processor 1306. The BC component 198 may be one or more hardware components that are specifically configured to perform the process / algorithm, implemented by one or more processors configured to perform the process / algorithm, stored in a computer-readable medium for implementation by one or more processors, or some combination thereof. As shown, the device 1304 may include multiple components configured for various functions. In one configuration, the device 1304 (and specifically, the cellular baseband processor 1324 and / or the application processor 1306) includes a component for sending an indication of BR capability to a network entity. In some aspects, the device 1304 may also include a component for receiving a first message from the network entity, the first message indicating that the UE will remain in the MR state or transition to the BR state. In some aspects, the device 1304 may also include a component for receiving a notification indicating support for backscatter communication (BC) from the network entity, wherein the indication of the BR capability is sent based on the notification. In some aspects, the device 1304 may also include a component for remaining in the MR state or transitioning to the BR state based on the first message. In some aspects, the device 1304 may also include a component for communicating with the network entity based on remaining in the MR state or transitioning to the BR state, wherein the communication with the network entity is based on the received first message. In some aspects, the device 1304 may also include a component for receiving one or more sounding signals from the network entity before transitioning to the BR state. In some aspects, the device 1304 may also include a component for sending measurements associated with the one or more sounding signals before transitioning to the BR state or after transitioning to the BR state. In some aspects, the apparatus 1304 may also include a component for receiving a second carrier for powering the passive BR at a first opportunity before a second opportunity, wherein the second opportunity is configured to transition back to the MR state. In some aspects, the apparatus 1304 may also include a component for transitioning back to the MR state based on a failure to power the passive BR from the second carrier. In some aspects, the apparatus 1304 may also include a component for receiving one or more sounding signals from the network entity before transitioning to the BR state. In some aspects, the apparatus 1304 may also include a component for sending measurements associated with the one or more sounding signals before transitioning to the BR state or after transitioning to the BR state.In some aspects, the device 1304 may also include a component for adjusting a power amplifier (PA) associated with the UE based on the measurement. In some aspects, the device 1304 may also include a component for receiving a wake-up signal (WUS) from the network entity, wherein the WUS indicates a transition back to the MR state. In some aspects, the device 1304 may also include a component for sending a second message to the network entity, wherein the second message indicates a request to transition from the MR state to the BR state. In some aspects, the device 1304 may also include a component for receiving a third message from the network entity, wherein the third message indicates that the UE will transition from the MR state to the BR state. The component may be a BC component 198 of the device 1304 configured to perform the functions recorded by the component. As described herein, the device 1304 may include a TX processor 368, an RX processor 356, and a controller / processor 359. Therefore, in one configuration, the component may be a TX processor 368, an RX processor 356, and / or a controller / processor 359 configured to perform the functions recorded by the component.

[0131] Fig.141400 is a diagram illustrating an example of a hardware implementation of a network entity 1402. The network entity 1402 may be a BS, a component of a BS, or may implement BS functionality. The network entity 1402 may include at least one of a CU 1410, a DU 1430, or a RU 1440. For example, depending on the layer functionality handled by the component 199, the network entity 1402 may include a CU 1410; both the CU 1410 and the DU 1430; each of the CU 1410, the DU 1430, and the RU 1440; the DU 1430; both the DU 1430 and the RU 1440; or the RU 1440. The CU 1410 may include a CU processor 1412. The CU processor 1412 may include an on-chip memory 1412'. In some aspects, the CU 1410 may also include an additional memory module 1414 and a communication interface 1418. CU 1410 communicates with DU 1430 via a midhaul link, such as an F1 interface. DU 1430 may include a DU processor 1432. DU processor 1432 may include on-chip memory 1432'. In some aspects, DU 1430 may also include an additional memory module 1434 and a communication interface 1438. DU 1430 communicates with RU 1440 via a fronthaul link. RU 1440 may include a RU processor 1442. RU processor 1442 may include on-chip memory 1442'. In some aspects, RU 1440 may also include an additional memory module 1444, one or more transceivers 1446, an antenna 1480, and a communication interface 1448. RU 1440 communicates with UE 104. On-chip memory 1412', 1432', 1442' and additional memory modules 1414, 1434, 1444 may each be considered a computer-readable medium / memory. Each computer readable medium / memory may be non-transitory. Each of processors 1412, 1432, 1442 is responsible for general processing, including executing software stored on the computer readable medium / memory. The software, when executed by the corresponding processor, causes the processor to perform the various functions described herein. The computer readable medium / memory may also be used to store data manipulated by the processor when executing the software.

[0132] As discussed herein, in some aspects, the BC configuration component 199 may be configured to receive an indication of a BR capability associated with the UE. In some aspects, the BC component 199 may be further configured to send a first message to the UE, the first message indicating that the UE will remain in the MR state or transition to the BR state. The BC component 199 may be within one or more processors of one or more of the CU 1410, the DU 1430, and the RU 1440. The BC component 199 may be one or more hardware components that are specifically configured to perform the process / algorithm, implemented by one or more processors configured to perform the process / algorithm, stored in a computer-readable medium so as to be implemented by one or more processors, or some combination thereof. The network entity 1402 may include a variety of components configured for various functions. In one configuration, the network entity 1402 includes a component for receiving an indication of a BR capability associated with the UE. In some aspects, the network entity 1402 may also include a component for sending a first message to the UE, the first message indicating that the UE will remain in the MR state or transition to the BR state. In some aspects, the network entity 1402 may also include a component for sending a notification indicating support for backscatter communication (BC), wherein the indication of the BR capability is received based on the notification. In some aspects, the network entity 1402 may also include a component for communicating with the UE based on the MR state or the BR state, wherein the communication with the UE is based on the first message sent. In some aspects, the network entity 1402 may also include a component for sending one or more sounding signals to the UE. In some aspects, the network entity 1402 may also include a component for receiving a measurement associated with the one or more sounding signals from the UE. In some aspects, the network entity 1402 may also include a component for adjusting the power of the first carrier based on the measurement. In some aspects, the network entity 1402 may also include a component for sending a second carrier for powering the passive BR at a first opportunity before a second opportunity, wherein the second opportunity is configured for the MR state. In some aspects, the network entity 1402 may also include a component for sending one or more sounding signals to the UE. In some aspects, the network entity 1402 may also include means for receiving measurements associated with the one or more sounding signals from the UE. In some aspects, the network entity 1402 may also include means for adjusting the power of at least one carrier based on the measurements. In some aspects, the network entity 1402 may also include means for sending a wake-up signal (WUS) to the UE, wherein the WUS indicates a transition back to the MR state. In some aspects, the network entity 1402 may also include means for receiving a second message from the UE, wherein the second message indicates a request to transition from the MR state to the BR state.In some aspects, the network entity 1402 may also include a means for sending a third message to the UE, wherein the third message indicates that the UE will transition from the MR state to the BR state. The means may be a BC component 199 of the network entity 1402 configured to perform the functions recited by the means. As described herein, the network entity 1402 may include a TX processor 316, an RX processor 370, and a controller / processor 375. Thus, in one configuration, the means may be a TX processor 316, an RX processor 370, and / or a controller / processor 375 configured to perform the functions recited by the means.

[0133] It should be understood that the specific order or hierarchy of the blocks in the disclosed process / flowchart is only an illustration of the exemplary method. It should be understood that the specific order or hierarchy of the blocks in the process / flowchart can be rearranged based on design preferences. In addition, some blocks can be combined or omitted. The attached method claims provide the elements of various blocks in a sample order, but are not limited to the specific order or hierarchy provided.

[0134] 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 various aspects described herein, but should be given the full scope consistent with the language claims. Unless otherwise specified, reference to an element in the singular form does not mean "one and only one", but "one or more". Terms such as "if", "when ..." and "while" do not mean an instantaneous time relationship or reaction. That is, these phrases, such as "when ...", do not mean an instantaneous action in response to the occurrence of an action or during the occurrence of an action, but simply imply that an action will occur if a condition is met, but no specific or instantaneous time limit is required for the occurrence of an action. The word "exemplary" is used herein to mean "used as an example, instance, or illustration". Any aspect described as "exemplary" herein is not necessarily interpreted as being preferred or having advantages over other aspects. Unless otherwise specified, the term "some" refers to one or more. Combinations such as "at least one of A, B, or C", "one or more of A, B, or C", "at least one of A, B and C", "one or more of A, B, and C", and "A, B, C, or any combination thereof" include any combination of A, B, and / or C, which may include multiple A, multiple B, or multiple C. Specifically, combinations such as "at least one of A, B, or C", "one or more of A, B, or C", "at least one of A, B, and C", "one or more of A, B, and C", and "A, B, C, or any combination thereof" may be only A, only B, only C, A and B, A and C, B and C, or A and B and C, where any such combination may contain one or more members of A, B, or C. A set should be interpreted as a set of elements, where the number of elements is one or more. Thus, for a set of X, X will include one or more elements. If the first device receives data from the second device or sends data to the second device, data can be directly received / sent between the first device and the second device, or data can be indirectly received / sent between the first device and the second device by a collection of devices. All structural and functional equivalents that are known to those of ordinary skill in the art or will be known later throughout the elements of the various aspects described in this disclosure are explicitly incorporated herein by reference, and are covered by the claims. In addition, anything disclosed herein is not intended to be dedicated to the public, regardless of whether such disclosures are explicitly recorded in the claims. "Module", "mechanism", "element", "equipment" and other words cannot replace the word "component". Therefore, no claim element will be understood as a functional component unless the element is explicitly recorded using the phrase "component for...".

[0135] As used in this disclosure outside of the claims, the phrase "based on" includes all interpretations and should not be limited to any single interpretation unless specifically recorded or indicated as such. For example, the phrase "based on A" (where "A" may be information, a condition, a factor, etc.) may be interpreted as: "at least based on A", "partially based on A", "at least partially based on A", "only based on A" or "based on A alone". Therefore, as disclosed herein, in one aspect, "based on A" may refer to "at least based on A". In another aspect, "based on A" may refer to "partially based on A". In another aspect, "based on A" may refer to "at least partially based on A". In another aspect, "based on A" may refer to "only based on A". In another aspect, "based on A" may refer to "based on A alone". In another aspect, "based on A" may refer to any combination of alternative interpretations. As used in the claims, the phrase "based on A" should be interpreted as "at least based on A", unless otherwise specifically stated.

[0136] The following aspects are merely illustrative and may be combined with other aspects or teachings described herein without limitation.

[0137] Aspect 1 is a method for communicating at a UE, the method comprising: sending an indication of BR capability to a network entity; and receiving a first message from the network entity, the first message indicating that the UE will remain in a MR state or transition to a BR state.

[0138] Aspect 2 is a method according to aspect 1, the method further comprising: receiving a notification indicating support for backscatter communication (BC) from the network entity, wherein the indication of the BR capability is sent based on the notification.

[0139] Aspect 3 is a method according to any one of Aspects 1 to 2, the method further comprising: maintaining the MR state or transitioning to the BR state based on the first message; and communicating with the network entity based on maintaining the MR state or transitioning to the BR state, wherein the communication with the network entity is based on the received first message.

[0140] Aspect 4 is a method according to any one of Aspects 1 to 3, wherein the communication is based on a transition to the BR state, wherein the BR state is based on a passive BR and is powered by a first carrier associated with the network entity, and the method further includes: receiving one or more detection signals from the network entity before transitioning to the BR state; and sending measurements associated with the one or more detection signals before or after transitioning to the BR state.

[0141] Aspect 5 is a method according to any one of Aspects 1 to 4, the method further comprising: receiving a second carrier for powering the passive BR at a first opportunity before a second opportunity, wherein the second opportunity is configured for transitioning back to the MR state; and transitioning back to the MR state based on a failure to power the passive BR from the second carrier.

[0142] Aspect 6 is a method according to any one of Aspects 1 to 3, wherein the communication is based on transitioning to the BR state, wherein the BR state is based on a semi-passive BR and is powered by a battery associated with the UE, and the method further includes: receiving one or more detection signals from the network entity before transitioning to the BR state; sending measurements associated with the one or more detection signals before or after transitioning to the BR state; and adjusting a power amplifier (PA) associated with the UE based on the measurements.

[0143] Aspect 7 is a method according to any one of aspects 1 to 3 and 6, the method further comprising: receiving a wake-up signal (WUS) from the network entity, wherein the WUS indicates transitioning back to the MR state.

[0144] Aspect 8 is a method according to any one of aspects 1 to 7, the method further comprising: sending a second message to the network entity, wherein the second message indicates a request to transition from the MR state to the BR state.

[0145] Aspect 9 is a method according to any one of aspects 1 to 8, wherein the first message is based on the second message and a downlink traffic pattern associated with the UE.

[0146] Aspect 10 is a method according to any one of aspects 1 to 9, wherein the first message is received before the second message is sent.

[0147] Aspect 11 is a method according to any one of aspects 1 to 9, wherein the second message is sent before the first message is received.

[0148] Aspect 12 is a method according to any one of aspects 1 to 11, wherein the second message further indicates a minimum duration associated with the BR state or a transition time to wakeup.

[0149] Aspect 13 is a method according to any one of aspects 1 to 12, wherein the second message is based on at least one of traffic arrival or battery status.

[0150] Aspect 14 is a method according to any one of aspects 1 to 13, the method further comprising: receiving a third message from the network entity, wherein the third message indicates that the UE is to transition from the MR state to the BR state.

[0151] Aspect 15 is a method for communicating at a network entity, the method comprising: receiving an indication of BR capabilities associated with a UE; and sending a first message to the UE, the first message indicating that the UE will remain in a MR state or transition to a BR state.

[0152] Aspect 16 is a method according to aspect 15, the method further comprising: sending a notification indicating support for backscatter communication (BC), wherein the indication of the BR capability is received based on the notification.

[0153] Aspect 17 is a method according to any one of aspects 15 to 16, the method further comprising: communicating with the UE based on the MR state or the BR state, wherein the communication with the UE is based on the sent first message.

[0154] Aspect 18 is a method according to any one of Aspects 15 to 17, wherein the communication is based on the BR state, wherein the BR state is based on a passive BR and is powered by a first carrier associated with the network entity, and the method also includes: sending one or more sounding signals to the UE; receiving measurements associated with the one or more sounding signals from the UE; and adjusting the power of the first carrier based on the measurements.

[0155] Aspect 19 is a method according to any one of aspects 15 to 18, the method further comprising: transmitting a second carrier for powering the passive BR at a first opportunity before a second opportunity, wherein the second opportunity is configured for the MR state.

[0156] Aspect 20 is a method according to any one of Aspects 15 to 17, wherein the communication is based on the BR state, wherein the BR state is based on a semi-passive BR and is powered by a battery associated with the UE, and the method further includes: sending one or more sounding signals to the UE; receiving measurements associated with the one or more sounding signals from the UE; and adjusting the power of at least one carrier based on the measurements.

[0157] Aspect 21 is a method according to any one of aspects 15 to 17 and 20, the method further comprising: sending a wake-up signal (WUS) to the UE, wherein the WUS indicates a transition back to the MR state.

[0158] Aspect 22 is a method according to any one of aspects 15 to 21, the method further comprising: receiving a second message from the UE, wherein the second message indicates a request to transition from the MR state to the BR state.

[0159] Aspect 23 is a method according to any one of aspects 15 to 22, wherein the first message is based on the second message and a downlink traffic pattern associated with the UE.

[0160] Aspect 24 is a method according to any one of aspects 15 to 23, wherein the first message is sent before the second message is received.

[0161] Aspect 25 is a method according to any one of aspects 15 to 23, wherein the second message is received before the first message is sent.

[0162] Aspect 26 is a method according to any one of aspects 15 to 25, wherein the second message further indicates a minimum duration associated with the BR state or a transition time to wakeup.

[0163] Aspect 27 is a method according to any one of aspects 15 to 26, wherein the second message is based on at least one of traffic arrival or battery status.

[0164] Aspect 28 is a method according to any one of aspects 15 to 27, the method further comprising: sending a third message to the UE, wherein the third message indicates that the UE is to transition from the MR state to the BR state.

[0165] Aspect 29 is an apparatus for wireless communication at a UE, the apparatus comprising a memory and at least one processor coupled to the memory, and the at least one processor is configured to perform a method according to any one of aspects 1 to 14 based at least in part on information stored in the memory. The apparatus may include at least one of a transceiver or an antenna coupled to the at least one processor.

[0166] Aspect 30 is an apparatus for wireless communication, the apparatus comprising means for performing a method according to any one of aspects 1 to 14.

[0167] Aspect 31 is a non-transitory computer-readable medium comprising instructions, which, when executed by an apparatus, cause the apparatus to perform the method according to any one of aspects 1 to 14.

[0168] Aspect 32 is an apparatus for wireless communication at a network entity, the apparatus comprising a memory and at least one processor coupled to the memory, and the at least one processor is configured to perform a method according to any one of aspects 15 to 28 based at least in part on information stored in the memory. The apparatus may include at least one of a transceiver or an antenna coupled to the at least one processor.

[0169] Aspect 33 is an apparatus for wireless communication, the apparatus comprising means for performing a method according to any one of aspects 15 to 28.

[0170] Aspect 34 is a non-transitory computer-readable medium comprising instructions which, when executed by an apparatus, cause the apparatus to perform a method according to any one of aspects 15 to 28.

Claims

1. An apparatus for communicating at a user equipment (UE), the apparatus comprising: Memory; and at least one processor coupled to the memory and based at least in part on the information stored in the memory, the at least one processor configured to: sending an indication of backscatter radio (BR) capabilities to a network entity; and A first message is received from the network entity, the first message indicating that the UE is to remain in a master radio (MR) state or transition to a BR state.

2. The apparatus of claim 1 , wherein the at least one processor is further configured to: A notification is received from the network entity indicating support for backscatter communication (BC), wherein the indication of the BR capability is sent based on the notification.

3. The apparatus of claim 1 , wherein the at least one processor is further configured to: maintaining the MR state or transitioning to the BR state based on the first message; and Communicating with the network entity based on maintaining the MR state or transitioning to the BR state, wherein the communicating with the network entity is based on the received first message.

4. The apparatus of claim 3, wherein the communication is based on transitioning to the BR state, wherein the BR state is based on a passive BR and is powered by a first carrier associated with the network entity, and wherein the at least one processor is further configured to: receiving one or more probe signals from the network entity before transitioning to the BR state; and Measurements associated with the one or more probing signals are sent before transitioning to the BR state or after transitioning to the BR state.

5. The apparatus of claim 4, wherein the at least one processor is further configured to: receiving a second carrier for powering the passive BR at a first opportunity before a second opportunity, wherein the second opportunity is configured for transitioning back to the MR state; and Transitioning back to the MR state is based on a failure to power the passive BR from the second carrier.

6. The apparatus of claim 3, wherein the communication is based on transitioning to the BR state, wherein the BR state is based on a semi-passive BR and is powered by a battery associated with the UE, and wherein the at least one processor is further configured to: receiving one or more probe signals from the network entity before transitioning to the BR state; sending measurements associated with the one or more probing signals before transitioning to the BR state or after transitioning to the BR state; and A power amplifier (PA) associated with the UE is adjusted based on the measurements.

7. The apparatus of claim 6, wherein the at least one processor is further configured to: A wake-up signal (WUS) is received from the network entity, wherein the WUS indicates a transition back to the MR state.

8. The apparatus of claim 1, wherein the at least one processor is further configured to: A second message is sent to the network entity, wherein the second message indicates a request to transition from the MR state to the BR state.

9. The apparatus of claim 8, wherein the first message is based on the second message and a downlink traffic pattern associated with the UE.

10. The apparatus of claim 8, wherein the first message is received before the second message is sent.

11. The apparatus of claim 8, wherein the second message is sent before the first message is received.

12. The apparatus of claim 8, wherein the second message further indicates a minimum duration associated with the BR state or a transition time to wakeup.

13. The device of claim 8, wherein the second message is based on at least one of traffic arrival or battery status.

14. The apparatus of claim 1, further comprising at least one of a transceiver or an antenna coupled to the at least one processor, wherein the at least one processor is further configured to: A third message is received from the network entity, wherein the third message indicates that the UE is to transition from the MR state to the BR state.

15. An apparatus for communicating at a network entity, the apparatus comprising: Memory; and at least one processor coupled to the memory and based at least in part on the information stored in the memory, the at least one processor configured to: receiving an indication of backscatter radio (BR) capabilities associated with a user equipment (UE); and A first message is sent to the UE, the first message indicating that the UE is to remain in a master radio (MR) state or transition to a BR state.

16. The apparatus of claim 15, wherein the at least one processor is further configured to: An advertisement is sent indicating support for backscatter communications (BC), wherein the indication of the BR capability is received based on the advertisement.

17. The apparatus of claim 16, wherein the at least one processor is further configured to: Communicating with the UE based on the MR state or the BR state, wherein the communicating with the UE is based on the transmitted first message.

18. The apparatus of claim 17, wherein the communication is based on the BR state, wherein the BR state is based on a passive BR and is powered by a first carrier associated with the network entity, and wherein the at least one processor is further configured to: Sending one or more sounding signals to the UE; receiving, from the UE, measurements associated with the one or more sounding signals; and The power of the first carrier is adjusted based on the measurement.

19. The apparatus of claim 18, wherein the at least one processor is further configured to: A second carrier for powering the passive BR is transmitted at a first opportunity before a second opportunity, wherein the second opportunity is configured for the MR state.

20. The apparatus of claim 17, wherein the communication is based on the BR state, wherein the BR state is based on a semi-passive BR and is powered by a battery associated with the UE, and wherein the at least one processor is further configured to: Sending one or more sounding signals to the UE; receiving, from the UE, measurements associated with the one or more sounding signals; and The power of at least one carrier is adjusted based on the measurement.

21. The apparatus of claim 20, wherein the at least one processor is further configured to: A wake-up signal (WUS) is sent to the UE, wherein the WUS indicates a transition back to the MR state.

22. The apparatus of claim 15, wherein the at least one processor is further configured to: A second message is received from the UE, wherein the second message indicates a request to transition from the MR state to the BR state.

23. The apparatus of claim 22, wherein the first message is based on the second message and a downlink traffic pattern associated with the UE.

24. The apparatus of claim 22, wherein the first message is sent before the second message is received.

25. The apparatus of claim 22, wherein the second message is received before the first message is sent.

26. The apparatus of claim 22, wherein the second message further indicates a minimum duration associated with the BR state or a transition time to wakeup.

27. The device of claim 22, wherein the second message is based on at least one of traffic arrival or battery status.

28. The apparatus of claim 15, further comprising at least one of a transceiver or an antenna coupled to the at least one processor, wherein the at least one processor is further configured to: A third message is sent to the UE, wherein the third message indicates that the UE is to transition from the MR state to the BR state.

29. A method of communicating at a user equipment (UE), the method comprising: sending an indication of backscatter radio (BR) capabilities to a network entity; as well as A first message is received from the network entity, the first message indicating that the UE is to remain in a master radio (MR) state or transition to a BR state.

30. A method of communicating at a network entity, the method comprising: receiving an indication of backscatter radio (BR) capabilities associated with a user equipment (UE); as well as A first message is sent to the UE, the first message indicating that the UE is to remain in a master radio (MR) state or transition to a BR state.

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