Patent Application
20240259172
The present disclosure relates generally to communication systems, and more particularly, to a unified transmission configuration indicator (TCI) for downlink control information (DCI) format 1_2.
Wireless communication systems are widely deployed to provide various telecommunication services such as telephony, video, data, messaging, and broadcasts. 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.
These multiple access technologies have been adopted in various telecommunication standards to provide a common protocol that enables different wireless devices to communicate on a municipal, national, regional, and even global level. An example telecommunication standard is 5G New Radio (NR). 5G NR is part of a continuous mobile broadband evolution promulgated by Third Generation Partnership Project (3GPP) to meet new requirements associated with latency, reliability, security, scalability (e.g., with Internet of Things (IoT)), and other requirements. 5G NR includes services associated with enhanced mobile broadband (eMBB), massive machine type communications (mMTC), and ultra-reliable low latency communications (URLLC). Some aspects of 5G NR may be based on the 4G Long Term Evolution (LTE) standard. There exists a need for further improvements in 5G NR technology. These improvements may also be applicable to other multi-access technologies and the telecommunication standards that employ these technologies.
The following presents a simplified summary of one or more aspects in order to provide a basic understanding of such aspects. This summary is not an extensive overview of all contemplated aspects. This summary neither identifies key or critical elements of all aspects nor delineates the scope of any or all aspects. Its sole purpose is to present some concepts of one or more aspects in a simplified form as a prelude to the more detailed description that is presented later.
In an aspect of the disclosure, a method, a computer-readable medium, and an apparatus are provided. The apparatus may be a device at a UE. The device may be a processor and/or a modem at a UE or the UE itself. The apparatus receives an activation of a first number of activated transmission configuration indicator (TCI) codepoints. The apparatus receives a downlink control information (DCI) comprising one or more bits that indicate a TCI state associated with at least one DCI format, wherein the one or more bits support a second number of codepoints that is less than the first number of activated TCI codepoints. The apparatus interprets the TCI state indicated by the one or more bits based on a type of the at least one DCI format and the second number of codepoints being less than the first number of activated TCI codepoints. The apparatus communicates based on an interpretation of the TCI state in the DCI.
In an aspect of the disclosure, a method, a computer-readable medium, and an apparatus are provided. The apparatus may be a device at a network node. The device may be a processor and/or a modem at a network node or the network node itself. The apparatus provides an activation of a first number of activated transmission configuration indicator (TCI) codepoints. The apparatus configures a downlink control information (DCI) comprising one or more bits that indicate a TCI state associated with at least one DCI format, wherein the one or more bits support a second number of codepoints that is less than the first number of activated TCI codepoints. The apparatus provides, to a user equipment (UE), the DCI comprising the one or more bits that indicate the TCI state associated with the at least one DCI format, wherein the one or more bits support the second number of codepoints that is less than the first number of activated TCI codepoints. The apparatus communicates, with the UE, based on an interpretation of the TCI state in the DCI.
To the accomplishment of the foregoing and related ends, the one or more aspects comprise the features hereinafter fully described and particularly pointed out in the claims. The following description and the drawings set forth in detail certain illustrative features of the one or more aspects. These features are indicative, however, of but a few of the various ways in which the principles of various aspects may be employed.
DCI comprising DCI format 1_1/1_2 may be used for both TCI state indication and physical downlink shared channel (PDSCH) scheduling. With unified TCI, when the DCI comprising DCI format 1_1/1_2 is used as the TCI state indication, the DCI comprising DCI format 1_1/1_2 may or may not schedule PDSCH. If the network only intends to scheduled PDSCH, the network may set the TCI field within the DCI comprising DCI format 1_1/1_2 to a codepoint that was previously indicated, such that the TCI state is not changed. For DCI format 1_1, if the TCI field is configured to be present, the TCI field is comprised to have 3 bits (e.g., 0 or 3 bits). If the TCI field is present in DCI format 1_2 but the number (S) of TCI codepoints of the TCI field is less than the number of TCI codepoints that are activated by medium access control (MAC) control element (CE) (MAC-CE), then only the first S activated codepoints may be indicated by DCI format 1_2. In some instances, DCI format 1_1 indicates a TCI codepoint that is outside the first S codepoints. In such instances, DCI format 1_2 may not be used for PDSCH scheduling only and without a TCI state change. Any DCI format 1_2 will inevitably change the TCI state, which acts as a beam indication DCI, because the previously indicated TCI codepoint (e.g., by DCI format 1_1) cannot be indicated. As such, the network cannot use DCI format 1_2 for PDSCH scheduling unless the network also intends to change one or more beams according to one of the first S TCI codepoints.
Aspects presented herein provide a configuration for unified TCI for DCI format 1_2. A UE may be configured to interpret a TCI state indicated by one or more bits based on a type of DCI format. At least one advantage of the disclosure is that DCI format 1_2 may be utilized for scheduling PDSCH with or without changing the TCI state.
The detailed description set forth below in connection with the drawings describes various configurations and does not represent the only configurations in which the concepts described herein may be practiced. The detailed description includes specific details for the purpose of providing a thorough understanding of various concepts. However, these concepts may be practiced without these specific details. In some instances, well known structures and components are shown in block diagram form in order to avoid obscuring such concepts.
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 such elements are implemented as hardware or software depends upon the particular application and design constraints imposed on the overall system.
By way of example, an element, or any portion of an element, or any combination of elements may be implemented as a “processing system” that 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 a chip (SoC), baseband processors, field programmable gate arrays (FPGAs), programmable logic devices (PLDs), state machines, gated logic, discrete hardware circuits, and other suitable hardware configured to perform the various functionality described throughout this disclosure. One or more processors in the processing system may execute software. Software, whether referred to as software, firmware, middleware, microcode, hardware description language, or otherwise, shall be construed broadly to mean instructions, instruction sets, code, code segments, program code, programs, subprograms, software components, applications, software applications, software packages, routines, subroutines, objects, executables, threads of execution, procedures, functions, or any combination thereof.
Accordingly, in one or more example aspects, implementations, and/or use cases, the functions described may be implemented in hardware, software, or any combination thereof. If implemented in software, the functions may be stored on or encoded as one or more instructions or code on a computer-readable medium. Computer-readable media includes computer storage media. Storage media may be any available media that can be accessed by a computer. By way of example, such computer-readable media can comprise a random-access memory (RAM), a read-only memory (ROM), an electrically erasable programmable ROM (EEPROM), optical disk storage, magnetic disk storage, other magnetic storage devices, combinations of the 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.
While aspects, implementations, and/or use cases are described in this application by illustration to some examples, additional or different aspects, implementations and/or use cases may come about in many different arrangements and scenarios. Aspects, implementations, and/or use cases described herein may be implemented across many differing platform types, devices, systems, shapes, sizes, and packaging arrangements. For example, aspects, implementations, and/or use cases may come about via integrated chip implementations and other non-module-component based devices (e.g., end-user devices, vehicles, communication devices, computing devices, industrial equipment, retail/purchasing devices, medical devices, artificial intelligence (AI)-enabled devices, etc.). While some examples may or may not be specifically directed to use cases or applications, a wide assortment of applicability of described examples may occur. Aspects, implementations, and/or use cases may range a spectrum from chip-level or modular components to non-modular, non-chip-level implementations and further to aggregate, distributed, or original equipment manufacturer (OEM) devices or systems incorporating one or more techniques herein. In some practical settings, devices incorporating described aspects and features may also include additional components and features for implementation and practice of claimed and described aspect. For example, transmission and reception of wireless signals necessarily includes a number of components for analog and digital purposes (e.g., hardware components including antenna, RF-chains, power amplifiers, modulators, buffer, processor(s), interleaver, adders/summers, etc.). Techniques described herein may be practiced in a wide variety of devices, chip-level components, systems, distributed arrangements, aggregated or disaggregated components, end-user devices, etc. of varying sizes, shapes, and constitution.
Deployment of communication systems, such as 5G NR systems, may be arranged in multiple manners with various components or constituent parts. 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) performing base station functionality, may be implemented in an aggregated or disaggregated architecture. For example, a BS (such as a Node B (NB), evolved NB (eNB), NR BS, 5G NB, access point (AP), a transmit receive point (TRP), or a cell, etc.) may be implemented as an aggregated base station (also known as a standalone BS or a monolithic BS) or a disaggregated base station.
An aggregated base station may be configured to utilize a radio protocol stack that is physically or logically integrated within a single RAN node. A disaggregated base station may be configured to utilize a protocol stack that is physically or logically distributed among 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 throughout one or multiple other RAN nodes. The DUs may be implemented to communicate with one or more RUs. Each of the CU, DU and RU can be implemented as virtual units, i.e., a virtual central unit (VCU), a virtual distributed unit (VDU), or a virtual radio unit (VRU).
Base station operation or network design may consider aggregation characteristics of base station functionality. For example, disaggregated base stations may be utilized in an integrated access backhaul (IAB) network, an open radio access network (O-RAN (such as the network configuration sponsored by the O-RAN Alliance)), or a virtualized radio access network (vRAN, also known as a cloud radio access network (C-RAN)). Disaggregation may include distributing functionality across two or more units at various physical locations, as well as distributing functionality for at least one unit virtually, which can enable flexibility in network design. The various units of the disaggregated base station, or disaggregated RAN architecture, can be configured for wired or wireless communication with at least one other unit.
Each of the units, i.e., the CUS 110, the DUs 130, the RUs 140, as well as the Near-RT RICs 125, the Non-RT RICs 115, and the SMO Framework 105, may include one or more interfaces or be coupled to one or more interfaces configured to receive or to transmit signals, data, or information (collectively, signals) via a wired or wireless transmission medium. Each of the units, or an associated processor or controller providing instructions to the communication interfaces of the units, can be configured to communicate with one or more of the other units via the transmission medium. For example, the units can include a wired interface configured to receive or to transmit signals over a wired transmission medium to one or more of the other units. Additionally, the units can include a wireless interface, which may include a receiver, a transmitter, or a transceiver (such as an RF transceiver), configured to receive or to transmit signals, or both, over a wireless transmission medium to one or more of the other units.
In some aspects, the CU 110 may host one or more higher layer control functions. Such control functions can include radio resource control (RRC), packet data convergence protocol (PDCP), service data adaptation protocol (SDAP), or the like. Each control function can be implemented with an interface configured to communicate signals with other control functions hosted by the CU 110. The CU 110 may be configured to handle user plane functionality (i.e., Central Unit-User Plane (CU-UP)), control plane functionality (i.e., Central Unit-Control Plane (CU-CP)), or a combination thereof. In some implementations, the CU 110 can be logically split into one or more CU-UP units and one or more CU-CP units. The CU-UP unit can communicate bidirectionally with the CU-CP unit via an interface, such as an E1 interface when implemented in an O-RAN configuration. The CU 110 can be implemented to communicate with the DU 130, as necessary, for network control and signaling.
The DU 130 may correspond to a logical unit that includes one or more base station functions to control the operation of one or more RUs 140. In some aspects, the 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, demodulation, or the like) depending, at least in part, on a functional split, such as those defined by 3GPP. In some aspects, the DU 130 may further host one or more low PHY layers. Each layer (or module) can be implemented with an interface configured to communicate signals with other layers (and modules) hosted by the DU 130, or with the control functions hosted by the CU 110.
Lower-layer functionality can be implemented by one or more RUs 140. In some deployments, an RU 140, controlled by a 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, or the like), or both, based at least in part on the functional split, such as a lower layer functional split. In such an architecture, the RU(s) 140 can be implemented to handle over the air (OTA) communication with one or more UEs 104. In some implementations, real-time and non-real-time aspects of control and user plane communication with the RU(s) 140 can be controlled by the corresponding DU 130. In some scenarios, this configuration can enable the DU(s) 130 and the CU 110 to be implemented in a cloud-based RAN architecture, such as a vRAN architecture.
The SMO Framework 105 may be configured to support RAN deployment and provisioning of non-virtualized 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 that may be managed via an operations 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 life cycle management (such as to instantiate virtualized network elements) via a cloud computing platform interface (such as an O2 interface). Such virtualized network elements can include, but are not limited to, CUs 110, DUs 130, RUs 140 and Near-RT RICs 125. In some implementations, the SMO Framework 105 can communicate with a hardware aspect of a 4G RAN, such as an open eNB (O-eNB) 111, via an O1 interface. Additionally, in some implementations, the SMO Framework 105 can communicate directly with one or more RUs 140 via an O1 interface. The SMO Framework 105 also may include a Non-RT RIC 115 configured to support functionality of the SMO Framework 105.
The Non-RT RIC 115 may be configured to include a logical function that enables non-real-time control and optimization of RAN elements and resources, artificial intelligence (AI)/machine learning (ML) (AI/ML) workflows including model training and updates, or policy-based guidance of applications/features in the Near-RT RIC 125. The Non-RT RIC 115 may be coupled to or communicate with (such as via an A1 interface) the Near-RT RIC 125. The Near-RT RIC 125 may be configured to include a logical function that enables near-real-time control and optimization of RAN elements and resources via data collection and actions over an interface (such as via an E2 interface) connecting one or more CUs 110, one or more DUs 130, or both, as well as an O-eNB, with the Near-RT RIC 125.
In some implementations, to generate AI/ML models to be deployed in the Near-RT RIC 125, the Non-RT RIC 115 may receive parameters or external enrichment information from external servers. Such information may be utilized by the Near-RT RIC 125 and may be received at the SMO Framework 105 or the Non-RT RIC 115 from non-network data sources or from network functions. 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 for performance and employ AI/ML models to perform corrective actions through the SMO Framework 105 (such as reconfiguration via 01) or via creation of RAN management policies (such as A1 policies).
At least one of the CU 110, the DU 130, and the RU 140 may be referred to as a base station 102. Accordingly, a base station 102 may include one or more of the CU 110, the DU 130, and the RU 140 (each component indicated with dotted lines to signify that each component may or may not be included in the base station 102). The base station 102 provides an access point to the core network 120 for a UE 104. The base stations 102 may include macrocells (high power cellular base station) and/or small cells (low power cellular base station). The small cells include femtocells, picocells, and microcells. A network that includes both small cell and macrocells may be known as a heterogeneous network. A heterogeneous network may also include Home Evolved Node Bs (eNBs) (HeNBs), which may provide service to a restricted group known as a closed subscriber group (CSG). The communication links between the RUs 140 and the UEs 104 may include uplink (UL) (also referred to as reverse link) transmissions from a UE 104 to an RU 140 and/or downlink (DL) (also referred to as forward link) transmissions from an RU 140 to a UE 104. The communication links may use multiple-input and multiple-output (MIMO) antenna technology, including spatial multiplexing, beamforming, and/or transmit diversity. The communication links may be through one or more carriers. The base stations 102/UEs 104 may use spectrum up to Y MHz (e.g., 5, 10, 15, 20, 100, 400, etc. MHz) bandwidth per carrier allocated in a carrier aggregation of up to a total of Yx MHz (x component carriers) used for transmission in each direction. The carriers may or may not be adjacent to each other. Allocation of carriers may be asymmetric with respect to DL and UL (e.g., more or fewer carriers may be allocated for DL than for UL). The component carriers may include a primary component carrier and one or more secondary component carriers. A primary component carrier may be referred to as a primary cell (PCell) and a secondary component carrier may be referred to as a secondary cell (SCell).
Certain UEs 104 may communicate with each other using device-to-device (D2D) communication link 158. The D2D communication link 158 may use the 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). D2D communication may be through a variety of wireless D2D communications systems, such as for example, Bluetooth, Wi-Fi based on the Institute of Electrical and Electronics Engineers (IEEE) 802.11 standard, LTE, or NR.
The wireless communications system may further include a Wi-Fi AP 150 in communication with UEs 104 (also referred to as Wi-Fi stations (STAs)) via communication link 154, e.g., in a 5 GHz unlicensed frequency spectrum or the like. When communicating in an unlicensed frequency spectrum, the UEs 104/AP 150 may perform a clear channel assessment (CCA) prior to communicating in order to determine whether the channel is available.
The electromagnetic spectrum is often subdivided, based on frequency/wavelength, into various classes, bands, channels, etc. 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 referred to (interchangeably) as a “sub-6 GHz” band in various documents and articles. A similar nomenclature issue sometimes occurs with regard to FR2, which is often referred to (interchangeably) as a “millimeter wave” band in documents and articles, despite being different from the extremely high frequency (EHF) band (30 GHz-300 GHz) which is identified by the International Telecommunications Union (ITU) as a “millimeter wave” band.
The frequencies between FR1 and FR2 are often referred to as mid-band frequencies. Recent 5G NR studies have identified an operating band for these mid-band frequencies as frequency range designation FR3 (7.125 GHZ-24.25 GHZ). Frequency bands falling within FR3 may inherit FR1 characteristics and/or FR2 characteristics, and thus may effectively extend features of FR1 and/or FR2 into mid-band frequencies. In addition, higher frequency bands are currently being explored to extend 5G NR operation beyond 52.6 GHz. For example, three higher operating bands have been identified as frequency range designations FR2-2 (52.6 GHz-71 GHz), FR4 (71 GHz-114.25 GHZ), and FR5 (114.25 GHz-300 GHz). Each of these higher frequency bands falls within the EHF band.
With the above aspects in mind, unless specifically stated otherwise, the term “sub-6 GHz” or the like if used herein may broadly represent frequencies that may be less than 6 GHZ, may be within FR1, or may include mid-band frequencies. Further, unless specifically stated otherwise, the term “millimeter wave” or the like if used herein may broadly represent frequencies that may include mid-band frequencies, may be within FR2, FR4, FR2-2, and/or FR5, or may be within the EHF band.
The base station 102 and the UE 104 may each include a plurality of antennas, such as antenna elements, antenna panels, and/or antenna arrays to facilitate beamforming. The base station 102 may transmit 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 transmit 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 and transmit directions for each of the base station 102/UE 104. The transmit and receive directions for the base station 102 may or may not be the same. The transmit and receive directions for the UE 104 may or may not be the same.
The base station 102 may include and/or be referred to as a gNB, Node B, eNB, an access point, a base transceiver station, a radio base station, a radio transceiver, a transceiver function, a basic service set (BSS), an extended service set (ESS), a transmit reception point (TRP), network node, network entity, network equipment, or some other suitable terminology. The base station 102 can be implemented as an integrated access and backhaul (IAB) node, a relay node, a sidelink node, an aggregated (monolithic) base station with a baseband unit (BBU) (including a CU and a DU) and an RU, or as a disaggregated base station including one or more of a CU, a DU, and/or an RU. The set of base stations, which may include disaggregated base stations and/or aggregated base stations, may be referred to as next generation (NG) RAN (NG-RAN).
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. The AMF 161 is the control node that processes the signaling between the UEs 104 and the core network 120. The AMF 161 supports registration management, connection management, mobility management, and other functions. The SMF 162 supports session management and other functions. The UPF 163 supports packet routing, packet forwarding, and other functions. The UDM 164 supports the generation of authentication and key agreement (AKA) credentials, user identification handling, access authorization, and subscription management. The 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, generally, 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, the LMF 166, a position determination entity (PDE), a serving mobile location center (SMLC), a mobile positioning center (MPC), or the like. The GMLC 165 and the LMF 166 support UE location services. The GMLC 165 provides an interface for clients/applications (e.g., emergency services) for accessing UE positioning information. The LMF 166 receives measurements and assistance information from the NG-RAN and the UE 104 via the AMF 161 to compute the position of the UE 104. The NG-RAN may utilize one or more positioning methods in order to determine the position of the UE 104. Positioning the UE 104 may involve signal measurements, a position estimate, and an optional velocity computation based on the measurements. The signal measurements may be made by the UE 104 and/or the serving base station 102. The signals measured may be based on one or more of a satellite positioning system (SPS) 170 (e.g., one or more of a Global Navigation Satellite System (GNSS), global position system (GPS), non-terrestrial network (NTN), or other satellite position/location system), LTE signals, wireless local area network (WLAN) signals, Bluetooth signals, a terrestrial beacon system (TBS), sensor-based information (e.g., barometric pressure sensor, motion sensor), NR enhanced cell ID (NR E-CID) methods, 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 other systems/signals/sensors.
Examples of UEs 104 include a cellular phone, a smart phone, a session initiation protocol (SIP) phone, a laptop, a personal digital assistant (PDA), a satellite radio, a global positioning system, a multimedia device, a video device, a digital audio player (e.g., MP3 player), a camera, a game console, a tablet, a smart device, a wearable device, a vehicle, an electric meter, a gas pump, a large or small kitchen appliance, a healthcare device, an implant, a sensor/actuator, a display, or any other similar functioning device. Some of the UEs 104 may be referred to as IoT devices (e.g., parking meter, gas pump, toaster, vehicles, heart monitor, etc.). The UE 104 may also be referred to as a station, a mobile station, a subscriber station, a mobile unit, a subscriber unit, a wireless unit, a remote unit, a mobile device, a wireless device, a wireless communications device, a remote device, a mobile subscriber station, an access terminal, a mobile terminal, a wireless terminal, a remote terminal, a handset, a user agent, a mobile client, a client, or some other suitable terminology. In some scenarios, the term UE may also apply to one or more companion devices such as in a device constellation arrangement. One or more of these devices may collectively access the network and/or individually access the network.
Referring again to
Referring again to
Although the following description may be focused 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.
For normal CP (14 symbols/slot), different numerologies μ 0 to 4 allow for 1, 2, 4, 8, and 16 slots, respectively, per subframe. For extended CP, the numerology 2 allows for 4 slots per subframe. Accordingly, for normal CP and numerology μ, there are 14 symbols/slot and 2μ slots/subframe. The subcarrier spacing may be equal to 2μ*15 kHz, where u is the numerology 0 to 4. As such, the numerology μ=0 has a subcarrier spacing of 15 kHz and the numerology μ=4 has a subcarrier spacing of 240 kHz. The symbol length/duration is inversely related to the subcarrier spacing. FIGS. 2A-2D provide an example of normal CP with 14 symbols per slot and numerology μ=2 with 4 slots per subframe. The slot duration is 0.25 ms, the subcarrier spacing is 60 kHz, and the symbol duration is approximately 16.67 μs. Within a set of frames, there may be one or more different bandwidth parts (BWPs) (see
A resource grid may be used to represent the frame structure. Each time slot includes a resource block (RB) (also referred to as physical RBs (PRBs)) that extends 12 consecutive subcarriers. The resource grid is divided into multiple resource elements (REs). The number of bits carried by each RE depends on the modulation scheme.
As illustrated in
As illustrated in
The transmit (TX) processor 316 and the receive (RX) processor 370 implement layer 1 functionality associated with various signal processing functions. Layer 1, which includes a physical (PHY) layer, may include error detection on the transport channels, forward error correction (FEC) coding/decoding of the transport channels, interleaving, rate matching, mapping onto physical channels, modulation/demodulation of physical channels, and MIMO antenna processing. The TX processor 316 handles mapping to signal constellations based on various modulation schemes (e.g., binary phase-shift keying (BPSK), quadrature phase-shift keying (QPSK), M-phase-shift keying (M-PSK), M-quadrature amplitude modulation (M-QAM)). The coded and modulated symbols may then be split into parallel streams. Each stream may 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 together 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 produce multiple spatial streams. Channel estimates from a channel estimator 374 may be used to determine the coding and modulation scheme, as well as for spatial processing. The channel estimate may be derived from a reference signal and/or channel condition feedback transmitted 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 respective spatial stream for transmission.
At the UE 350, each receiver 354Rx receives a signal through its respective antenna 352. Each receiver 354Rx recovers information modulated onto an RF carrier and provides the information to the 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 may perform spatial processing on the information to recover any spatial streams destined for the UE 350. If multiple spatial streams are destined for the UE 350, they may be combined by the RX processor 356 into a single OFDM symbol stream. 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 comprises a separate OFDM symbol stream for each subcarrier of the OFDM signal. The symbols on each subcarrier, and the reference signal, are recovered and demodulated by determining the most likely signal constellation points transmitted by the base station 310. These soft decisions may be based on channel estimates computed by the channel estimator 358. The soft decisions are then decoded and deinterleaved to recover the data and control signals that were originally transmitted by the base station 310 on the physical channel. The data and control signals are then provided to the controller/processor 359, which implements layer 3 and layer 2 functionality.
The controller/processor 359 can 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 and logical channels, packet reassembly, deciphering, header decompression, and control signal processing to recover IP packets. The controller/processor 359 is also responsible for error detection using an ACK and/or NACK protocol to support HARQ operations.
Similar to the functionality described in connection with the DL transmission by the base station 310, the controller/processor 359 provides RRC layer functionality associated with system information (e.g., MIB, SIBs) acquisition, RRC connections, and measurement reporting; PDCP layer functionality associated with header compression/decompression, and security (ciphering, deciphering, integrity protection, integrity verification); RLC layer functionality associated with the transfer of upper layer PDUs, error correction through ARQ, concatenation, segmentation, and reassembly of RLC 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 TBs, demultiplexing of MAC SDUs from TBs, scheduling information reporting, error correction through HARQ, priority handling, and logical channel prioritization.
Channel estimates derived by a channel estimator 358 from a reference signal or feedback transmitted 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 antenna 352 via separate transmitters 354Tx. Each transmitter 354Tx may modulate an RF carrier with a respective spatial stream for transmission.
The UL transmission is processed at the base station 310 in a manner similar to that described in connection with the receiver function at the UE 350. Each receiver 318Rx receives a signal through its respective antenna 320. Each receiver 318Rx recovers information modulated onto an RF carrier and provides the information to a RX processor 370.
The controller/processor 375 can 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 and logical channels, packet reassembly, deciphering, header decompression, control signal processing to recover IP packets. The controller/processor 375 is also responsible for error detection using an ACK and/or NACK protocol to support HARQ operations.
At least one of the TX processor 368, the RX processor 356, and the controller/processor 359 may be configured to perform aspects in connection with the TCI component 198 of
At least one of the TX processor 316, the RX processor 370, and the controller/processor 375 may be configured to perform aspects in connection with the TCI component 199 of
As described in connection with example 400 in
In response to different conditions, the UE 404 may determine to switch beams, e.g., between beams 402a-402h. The beam at the UE 404 may be used for reception of downlink communication and/or transmission of uplink communication. In some examples, the base station 402 may send a transmission that triggers a beam switch by the UE 404. For example, the base station 402 may indicate a transmission configuration indication (TCI) state change, and in response, the UE 404 may switch to a new beam for the new TCI state of the base station 402. In some instances, a UE may receive a signal, from a base station, configured to trigger a transmission configuration indication (TCI) state change via, for example, a MAC control element (CE) command. The TCI state change may cause the UE to find the best UE receive beam corresponding to the TCI state from the base station, and switch to such beam. Switching beams may allow for enhanced or improved connection between the UE and the base station by ensuring that the transmitter and receiver use the same configured set of beams for communication. In some aspects, a single MAC-CE command may be sent by the base station to trigger the changing of the TCI state on multiple CCs.
A TCI state may include quasi co-location (QCL) information that the UE can use to derive timing/frequency error and/or transmission/reception spatial filtering for transmitting/receiving a signal. Two antenna ports are said to be quasi co-located if properties of the channel over which a symbol on one antenna port is conveyed can be inferred from the channel over which a symbol on the other antenna port is conveyed. The base station may indicate a TCI state to the UE as a transmission configuration that indicates QCL relationships between one signal (e.g., a reference signal) and the signal to be transmitted/received. For example, a TCI state may indicate a QCL relationship between DL RSs in one RS set and PDSCH/PDCCH DM-RS ports. TCI states can provide information about different beam selections for the UE to use for transmitting/receiving various signals.
In some wireless communication systems, such as a wireless communication system under a unified TCI framework, a pool of joint DL/UL TCI states may be used for joint DL/UL TCI state updates for beam indication. For example, the base station 402 may transmit a pool of joint DL/UL TCI states to the UE 404. The UE 404 may determine to switch transmission beams and/or reception beams based on the joint DL/UL TCI states. In some aspects, the TCI state pool for separate DL and UL TCI state updates may be used. In some aspects, the base station 402 may use RRC signaling to configure the TCI state pool. In some aspects, the joint TCI may or may not include UL specific parameter(s) such as UL PC/timing parameters, PLRS, panel-related indication, or the like. If the joint TCI includes the UL specific parameter(s), the parameters may be used for the UL transmission of the DL and UL transmissions to which the joint TCI is applied.
Under a unified TCI framework, different types of common TCI states may be indicated. For example, a type 1 TCI may be a joint DL/UL common TCI state to indicate a common beam for at least one DL channel or RS and at least one UL channel or RS. A type 2 TCI may be a separate DL (e.g., separate from UL) common TCI state to indicate a common beam for more than one DL channel or RS. A type 3 TCI may be a separate UL common TCI state to indicate a common beam for more than one UL channel/RS. A type 4 TCI may be a separate DL single channel or RS TCI state to indicate a beam for a single DL channel or RS. A type 5 TCI may be a separate UL single channel or RS TCI state to indicate a beam for a single UL channel or RS. A type 6 TCI may include UL spatial relation information (e.g., such as sounding reference signal (SRS) resource indicator (SRI)) to indicate a beam for a single UL channel or RS. An example RS may be an SSB, a tracking reference signal (TRS) and associated CSI-RS for tracking, a CSI-RS for beam management, a CSI-RS for CQI management, a DM-RS associated with non-UE-dedicated reception on PDSCH and a subset (which may be a full set) of control resource sets (CORESETs), or the like. A TCI state may be defined to represent at least one source RS to provide a reference (e.g., UE assumption) for determining quasi-co-location (QCL) or spatial filters. For example, a TCI state may define a QCL assumption between a source RS and a target RS.
Before receiving a TCI state, a UE may assume that the antenna ports of one DM-RS port group of a PDSCH are spatially quasi-co-located (QCLed) with an SSB determined in the initial access procedure with respect to one or more of: a Doppler shift, a Doppler spread, an average delay, a delay spread, a set of spatial Rx parameters, or the like. After receiving the new TCI state, the UE may assume that the antenna ports of one DM-RS port group of a PDSCH of a serving cell are QCLed with the RS(s) in the RS set with respect to the QCL type parameter(s) given by the indicated TCI state. Regarding the QCL types, QCL type A may include the Doppler shift, the Doppler spread, the average delay, and the delay spread; QCL type B may include the Doppler shift and the Doppler spread; QCL type C may include the Doppler shift and the average delay; and QCL type D may include the spatial Rx parameters (e.g., associated with beam information such as beamforming properties for finding a beam).
In another aspect, a spatial relation change, such as a spatial relation update, may trigger the UE to switch beams. Beamforming may be applied to uplink channels, such as but not limited to PUCCH. Beamforming may be based on configuring one or more spatial relations between the uplink and downlink signals. Spatial relation indicates that a UE may transmit the uplink signal using the same beam as it used for receiving the corresponding downlink signal.
In another aspect, the base station 402 may change a pathloss reference signal configuration that the UE uses to determine power control for uplink transmissions, such as SRS, PUCCH, and/or PUSCH. In response to the change in the pathloss reference signal, the UE 404 may determine to switch to a new beam.
DCI may be used for scheduling PDSCH. For example, DCI format 1_1 and 1_2 may be used for scheduling a PDSCH. In some aspects, DCI format 1_2 in addition to DCI format 1_1 may allow for more flexible size of the DCI, which may be controlled by new or separate RRC configurations. The size of the DCI may be reduced (e.g., compact DCI) to provide an enhanced PDCCH reliability. With reference to
A MAC-CE may activate a number of TCI codepoints (e.g., up to 8 codepoints), where each codepoint maps to one or more TCI states. A DCI may indicate one of the TCI codepoints based on the TCI field within the DCI. For DCI format 1_1, if the TCI field is configured to be present, the TCI field may have 3 bits (e.g., 8 codepoints). For DCI format 1_2, when the number of codepoints S in the TCI field is less than the number of TCI codepoints that are activated by the activation command (e.g., MAC-CE), only the first S activated codepoints are applied for DCI format 1_2.
For systems utilizing unified TCI, the unified TCI may include DL TCI states, UL TCI states, or joint DL/UL TCI states which may be configured via RRC signaling. The MAC-CE may activate a number of RRC configured TCI states and map to TCI field codepoints with one or more of the following possibilities: one TCI field codepoint represents a joint DL/UL TCI state: Used for joint DL/UL beam indication; one TCI field codepoint represents a pair of DL TCI state and UL TCI state (e.g., used for separate DL/UL beam indication); one TCI field codepoint represents only a DL TCI state: Used for only DL beam indication; or one TCI field codepoint represents only an UL TCI state (e.g., used for UL beam indication). In some instances, if the MAC-CE indicates the mapping to only a single TCI field codepoint, then the single TCI field codepoint may serve as a beam indication. For example, a period of time (e.g., 3 ms) after a HARQ-ACK to PDSCH carrying the MAC-CE, the beam indication may be applied. In some instances, if the MAC-CE indicates a mapping to more than one TCI field codepoint DL DCI (e.g., DCI format 1_1 or 1_2) with or without a DL assignment can indicate a beam through the TCI field codepoint. For example, the beam indication may be applied in a first slot that is at least Y symbols (e.g., RRC configured based on UE capability) after the last symbol of the PUCCH carrying the HARQ-ACK in response to the DCI, as shown, for example, in diagram 600 of
DCI comprising DCI format 1_1/1_2 may be used for both TCI state indication and PDSCH scheduling. With unified TCI, when the DCI comprising DCI format 1_1/1_2 is used as the TCI state indication, the DCI comprising DCI format 1_1/1_2 may or may not schedule PDSCH. If the network only intends to scheduled PDSCH, the network may set the TCI field within the DCI comprising DCI format 1_1/1_2 to a codepoint that was previously indicated, such that the TCI state is not changed. For DCI format 1_1, if the TCI field is configured to be present, the TCI field is comprised to have 3 bits (e.g., 0 or 3 bits). If the TCI field is present in DCI format 1_2 but the number (S) of TCI codepoints of the TCI field is less than the number of TCI codepoints that are activated by the MAC-CE, then only the first S activated codepoints may be indicated by DCI format 1_2. For example, with reference to diagram 700 of
In some instances, DCI format 1_1 indicates a TCI codepoint that is outside the first S codepoints. In such instances, DCI format 1_2 may not be used for PDSCH scheduling only and without a TCI state change. Any DCI format 1_2 will inevitably change the TCI state, which acts as a beam indication DCI, because the previously indicated TCI codepoint (e.g., by DCI format 1_1) cannot be indicated, as shown for example in
Aspects presented herein provide a configuration for unified TCI for DCI format 1_2. A UE may be configured to interpret a TCI state indicated by one or more bits based on a type of DCI format. At least one advantage of the disclosure is that DCI format 1_2 may be utilized for scheduling PDSCH with or without changing the TCI state.
In instances where S is less than the number of TCI codepoints that are activated by the MAC-CE or activation command, the first S−1 activated codepoints may be indicated by the TCI field of DCI format 1_2 and a remaining codepoint (e.g., the first or last codepoint) may be reserved to indicate no TCI state change or update. This may be followed, in general, for DCI format 1_2, or in instances where the DCI format 1_2 schedules PDSCH. If DCI format 1_2 does not schedule PDSCH, then the DCI format 1_2 may be intended for a TCI state change. As such, the TCI field may indicate any of the first S activated codepoints, as shown in interpretation 804 of
At 1105, the base station 1104 may provide an RRC configuration. The RRC configuration may configure at least one or more of downlink TCI states, uplink TCI states, or joint downlink/uplink TCI states. At 1106, the base station 1104 may provide an activation of a first number of activated TCI codepoints. The base station may provide the activation of the first number of activated TCI codepoints to the UE 1102, as shown in connection with
At 1108, the base station 1104 may configure a DCI comprising one or more bits that indicate a TCI state associated. The base station may configure the DCI comprising the one or more bits that indicate the TCI state associated with at least one DCI format, as shown in connection with
At 1110, the base station 1104 may provide the DCI comprising the one or more bits that indicate the TCI state associated with the at least one DCI format. The base station may provide the DCI comprising the one or more bits that indicate the TCI state associated with the at least one DCI format to the UE 1102, as shown in connection with
At 1112, the UE 1102 may interpret the TCI state indicated by the one or more bits. The UE may interpret the TCI state indicated by the one or more bits based on a type of the at least one DCI format and the second number of codepoints being less than the first number of activated TCI codepoints, as shown in connection with
At 1114, in aspects where the DCI comprises DCI format 1_2, the UE 1102 may update the TCI state. The UE may update the TCI state if the interpretation indicates a new TCI state, as shown in connection with
At 1116, the UE may communicate based on an interpretation of the TCI state. The UE may communicate with the base station based on the interpretation of the TCI state in the DCI.
At 1202, the UE may receive an activation of a first number of activated TCI codepoints, as shown in connection with
At 1204, the UE may receive a DCI. For example, 1204 may be performed by TCI component 198 of apparatus 1404. The DCI may comprise one or more bits that indicate a TCI state associated with at least one DCI format, as shown in connection with
At 1206, the UE may interpret the TCI state indicated by the one or more bits. For example, 1206 may be performed by TCI component 198 of apparatus 1404. The UE may interpret the TCI state indicated by the one or more bits based on a type of the at least one DCI format and the second number of codepoints being less than the first number of activated TCI codepoints, as shown in connection with
At 1208, the UE may communicate based on an interpretation of the TCI state, as shown in connection with
At 1302, the UE may receive an activation of a first number of activated TCI codepoints, as shown in connection with
At 1304, the UE may receive a DCI. For example, 1304 may be performed by TCI component 198 of apparatus 1404. The DCI may comprise one or more bits that indicate a TCI state associated with at least one DCI format, as shown in connection with
At 1306, the UE may interpret the TCI state indicated by the one or more bits. For example, 1306 may be performed by TCI component 198 of apparatus 1404. The UE may interpret the TCI state indicated by the one or more bits based on a type of the at least one DCI format and the second number of codepoints being less than the first number of activated TCI codepoints, as shown in connection with
At 1308, in instances where the DCI comprises DCI format 1_2, the UE may update the TCI state. For example, 1308 may be performed by TCI component 198 of apparatus 1404. The UE may update the TCI state if the interpretation indicates a new TCI state, as shown in connection with
At 1310, in instances where the DCI comprises DCI format 1_2, the UE may communicate without a TCI state update. For example, 1310 may be performed by TCI component 198 of apparatus 1404. The UE may communicate without the TCI state update if the interpretation indicates a currently used TCI codepoint, as shown in connection with
At 1312, the UE may communicate based on an interpretation of the TCI state. For example, 1312 may be performed by TCI component 198 of apparatus 1404. The UE may communicate with a network entity based on the interpretation of the TCI state in the DCI, as shown in connection with
As discussed supra, the component 198 is configured to receive an activation of a first number of activated TCI codepoints; receive a DCI comprising one or more bits that indicate a TCI state associated with at least one DCI format, wherein the one or more bits support a second number of codepoints that is less than the first number of activated TCI codepoints; interpret the TCI state indicated by the one or more bits based on a type of the at least one DCI format and the second number of codepoints being less than the first number of activated TCI codepoints; and communicate based on an interpretation of the TCI state in the DCI. The component 198 may be within the cellular baseband processor 1424, the application processor 1406, or both the cellular baseband processor 1424 and the application processor 1406. The component 198 may be one or more hardware components specifically configured to carry out the stated processes/algorithm, implemented by one or more processors configured to perform the stated processes/algorithm, stored within a computer-readable medium for implementation by one or more processors, or some combination thereof. As shown, the apparatus 1404 may include a variety of components configured for various functions. In one configuration, the apparatus 1404, and in particular the cellular baseband processor 1424 and/or the application processor 1406, includes means for receiving an activation of a first number of activated TCI codepoints. The apparatus includes means for receiving a downlink control information (DCI) comprising one or more bits that indicate a TCI state associated with at least one DCI format. The one or more bits support a second number of codepoints that is less than the first number of activated TCI codepoints. The apparatus includes means for interpreting the TCI state indicated by the one or more bits based on a type of the at least one DCI format and the second number of codepoints being less than the first number of activated TCI codepoints. The apparatus includes means for communicating based on an interpretation of the TCI state in the DCI. The apparatus further includes means for updating the TCI state if the interpretation indicates a new TCI state. The apparatus further includes means for communicating without a TCI state update if the interpretation indicates a currently used TCI codepoint. The means may be the component 198 of the apparatus 1404 configured to perform the functions recited by the means. As described supra, the apparatus 1404 may include the TX processor 368, the RX processor 356, and the controller/processor 359. As such, in one configuration, the means may be the TX processor 368, the RX processor 356, and/or the controller/processor 359 configured to perform the functions recited by the means.
At 1502, the network entity may provide an activation of a first number of activated TCI codepoints, as shown in connection with
At 1504, the network entity may configure a DCI comprising one or more bits that indicate a TCI state associated. For example, 1504 may be performed by TCI component 199 of network entity 1602. The network entity may configure the DCI comprising the one or more bits that indicate the TCI state associated with at least one DCI format, as shown in connection with
At 1506, the network entity may provide the DCI comprising the one or more bits that indicate the TCI state associated with the at least one DCI format, as shown in connection with
At 1508, the network entity may communicate based on an interpretation of the TCI state in the DCI. For example, 1506 may be performed by TCI component 199 of network entity 1602. The network entity may communicate, with the UE, based on an interpretation of the TCI state in the DCI, as shown in connection with
As discussed supra, the component 199 is configured to provide an activation of a first number of activated TCI codepoints; configure a DCI comprising one or more bits that indicate a TCI state associated with at least one DCI format, wherein the one or more bits support a second number of codepoints that is less than the first number of activated TCI codepoints; provide, to a UE, the DCI comprising the one or more bits that indicate the TCI state associated with the at least one DCI format, wherein the one or more bits support the second number of codepoints that is less than the first number of activated TCI codepoints; and communicate, with the UE, based on an interpretation of the TCI state in the DCI. The component 199 may be within one or more processors of one or more of the CU 1610, DU 1630, and the RU 1640. The component 199 may be one or more hardware components specifically configured to carry out the stated processes/algorithm, implemented by one or more processors configured to perform the stated processes/algorithm, stored within a computer-readable medium for implementation by one or more processors, or some combination thereof. The network entity 1602 may include a variety of components configured for various functions. In one configuration, the network entity 1602 includes means for providing an activation of a first number of activated TCI codepoints. The network entity includes means for configuring a DCI comprising one or more bits that indicate a TCI state associated with at least one DCI format. The one or more bits support a second number of codepoints that is less than the first number of activated TCI codepoints. The network entity includes means for providing, to a UE, the DCI comprising the one or more bits that indicate the TCI state associated with the at least one DCI format. The one or more bits support the second number of codepoints that is less than the first number of activated TCI codepoints. The network entity includes means for communicating, with the UE, based on an interpretation of the TCI state in the DCI. The means may be the component 199 of the network entity 1602 configured to perform the functions recited by the means. As described supra, the network entity 1602 may include the TX processor 316, the RX processor 370, and the controller/processor 375. As such, in one configuration, the means may be the TX processor 316, the RX processor 370, and/or the controller/processor 375 configured to perform the functions recited by the means.
Aspects presented herein provide a configuration for unified TCI for DCI format 1_2. A UE may be configured to interpret a TCI state indicated by one or more bits based on a type of DCI format. At least one advantage of the disclosure is that DCI format 1_2 may be utilized for scheduling PDSCH with or without changing the TCI state. A UE may receive a DL DCI comprising one or more bits that indicate a TCI state associated with at least one DCI format. The UE may determine the TCI state indicated by the one or more bits based on a type of the at least one DCI format and the activated TCI codepoints.
It is understood that the specific order or hierarchy of blocks in the processes/flowcharts disclosed is an illustration of example approaches. Based upon design preferences, it is understood that the specific order or hierarchy of blocks in the processes/flowcharts may be rearranged. Further, some blocks may be combined or omitted. The accompanying method claims present elements of the various blocks in a sample order, and are not limited to the specific order or hierarchy presented.
The previous 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 readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other aspects. Thus, the claims are not limited to the aspects described herein, but are to be accorded the full scope consistent with the language claims. Reference to an element in the singular does not mean “one and only one” unless specifically so stated, but rather “one or more.” Terms such as “if,” “when,” and “while” do not imply an immediate temporal relationship or reaction. That is, these phrases, e.g., “when,” do not imply an immediate action in response to or during the occurrence of an action, but simply imply that if a condition is met then an action will occur, but without requiring a specific or immediate time constraint for the action to occur. The word “exemplary” is used herein to mean “serving as an example, instance, or illustration.” Any aspect described herein as “exemplary” is not necessarily to be construed as preferred or advantageous over other aspects. Unless specifically stated otherwise, the term “some” refers to one or more. Combinations such as “at least one of A, B, or C,” “one or more of A, B, or C,” “at least one of A, B, and C,” “one or more of A, B, and C,” and “A, B, C, or any combination thereof” include any combination of A, B, and/or C, and may include multiples of A, multiples of B, or multiples of 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 A only, B only, C only, A and B, A and C, B and C, or A and B and C, where any such combinations may contain one or more member or members of A, B, or C. Sets should be interpreted as a set of elements where the elements number one or more. Accordingly, for a set of X, X would include one or more elements. If a first apparatus receives data from or transmits data to a second apparatus, the data may be received/transmitted directly between the first and second apparatuses, or indirectly between the first and second apparatuses through a set of apparatuses. A device configured to “output” data, such as a transmission, signal, or message, may transmit the data, for example with a transceiver, or may send the data to a device that transmits the data. A device configured to “obtain” data, such as a transmission, signal, or message, may receive, for example with a transceiver, or may obtain the data from a device that receives the data. All structural and functional equivalents to the elements of the various aspects described throughout this disclosure that are known or later come to be known to those of ordinary skill in the art are expressly incorporated herein by reference and are encompassed by the claims. Moreover, nothing disclosed herein is dedicated to the public regardless of whether such disclosure is explicitly recited in the claims. The words “module,” “mechanism,” “element,” “device,” and the like may not be a substitute for the word “means.” As such, no claim element is to be construed as a means plus function unless the element is expressly recited using the phrase “means for.”
As used herein, the phrase “based on” shall not be construed as a reference to a closed set of information, one or more conditions, one or more factors, or the like. In other words, the phrase “based on A” (where “A” may be information, a condition, a factor, or the like) shall be construed as “based at least on A” unless specifically recited differently.
The following aspects are illustrative only and may be combined with other aspects or teachings described herein, without limitation.
Aspect 1 is a method of wireless communication at a UE comprising receiving an activation of a first number of activated TCI codepoints; receiving a DCI comprising one or more bits that indicate a TCI state associated with at least one DCI format, wherein the one or more bits support a second number of codepoints that is less than the first number of activated TCI codepoints; interpreting the TCI state indicated by the one or more bits based on a type of the at least one DCI format and the second number of codepoints being less than the first number of activated TCI codepoints; and communicating based on an interpretation of the TCI state in the DCI.
Aspect 2 is the method of aspect 1, further includes that the DCI comprises DCI format 1_2 further including updating the TCI state if the interpretation indicates a new TCI state; and communicating without a TCI state update if the interpretation indicates a currently used TCI codepoint.
Aspect 3 is the method of any of aspects 1 and 2, further includes that the UE determines an error based on the first number of activated TCI codepoints being more than the second number of codepoints that are supported by the one or more bits of the DCI.
Aspect 4 is the method of any of aspects 1-3, further includes that interpreting the TCI state indicated by the one or more bits includes determining the TCI state from a subset of the first number of activated TCI codepoints, the subset of the first number of activated TCI codepoints is one less than the second number of codepoints supported by the one or more bits, and a remaining TCI codepoint is reserved to indicate a lack of the update to the currently used TCI codepoint.
Aspect 5 is the method of any of aspects 1-4, further includes that interpreting the TCI state indicated by the one or more bits includes determining the TCI state from a subset of the first number of activated TCI codepoints, the subset of the first number of activated TCI codepoints including a group of the activated TCI codepoints that includes a current used TCI codepoint.
Aspect 6 is the method of any of aspects 1-5, further includes that the first number of activated TCI codepoints are grouped into one or more groups wherein a first group of the one or more groups comprises the current used TCI codepoint.
Aspect 7 is the method of any of aspects 1-6, further includes that interpreting the TCI state indicated by the one or more bits is further based on whether a physical downlink shared channel (PDSCH) is scheduled by the DCI, wherein the TCI state indicated in the DCI is not considered when the DCI schedules the PDSCH.
Aspect 8 is an apparatus for wireless communication at a UE including at least one processor coupled to a memory and at least one transceiver, the at least one processor configured to implement any of Aspects 1-7.
Aspect 9 is an apparatus for wireless communication at a UE including means for implementing any of Aspects 1-7.
Aspect 10 is a computer-readable medium storing computer executable code, where the code when executed by a processor causes the processor to implement any of Aspects 1-7.
Aspect 11 is a method of wireless communication at a network node comprising providing an activation of a first number of activated TCI codepoints; configuring a DCI comprising one or more bits that indicate a TCI state associated with at least one DCI format, wherein the one or more bits support a second number of codepoints that is less than the first number of activated TCI codepoints; providing, to a UE, the DCI comprising the one or more bits that indicate the TCI state associated with the at least one DCI format, wherein the one or more bits support the second number of codepoints that is less than the first number of activated TCI codepoints; and communicating, with the UE, based on an interpretation of the TCI state in the DCI.
Aspect 12 is the method of aspect 11, further includes that the DCI comprises DCI format 1_2.
Aspect 13 is the method of any of aspects 11 and 12, further includes that the first number of activated TCI codepoints is more than the second number of codepoints that are supported by the one or more bits of the DCI.
Aspect 14 is the method of any of aspects 11-13, further includes that the TCI state indicated by the one or more bits includes the TCI state from a subset of the first number of activated TCI codepoints, the subset of the first number of activated TCI codepoints is one less than the second number of codepoints supported by the one or more bits, and a remaining TCI codepoint is reserved to indicate a lack of an update to the at currently used TCI codepoint.
Aspect 15 is the method of any of aspects 11-14, further includes that the TCI state indicated by the one or more bits includes the TCI state from a subset of the first number of activated TCI codepoints, the subset of the first number of activated TCI codepoints including a group of the activated TCI codepoints that includes a current used TCI codepoint.
Aspect 16 is the method of any of aspects 11-15, further includes that the first number of activated TCI codepoints are grouped into one or more groups, wherein a first group of the one or more groups comprises the current used TCI codepoint.
Aspect 17 is the method of any of aspects 11-16, further includes that the TCI state indicated by the one or more bits is further based on whether a PDSCH is scheduled by the DCI, wherein the TCI state indicated in the DCI is not considered when the DCI schedules the PDSCH.
Aspect 18 is an apparatus for wireless communication at a UE including at least one processor coupled to a memory and at least one transceiver, the at least one processor configured to implement any of Aspects 11-18.
Aspect 19 is an apparatus for wireless communication at a UE including means for implementing any of Aspects 11-18.
Aspect 20 is a computer-readable medium storing computer executable code, where the code when executed by a processor causes the processor to implement any of Aspects 11-18.
