CN117750501A - Spatial and frequency domain beam management using time sequence information - Google Patents

Abstract

Spatial and frequency domain beam management using time sequence information. In one aspect of the invention, a method, computer-readable medium, and apparatus are provided. The apparatus may be a wireless device. The wireless device selects a first subset of beams to be used for beam management. The beam is from a set of first type beams for communication with a base station or UE. The wireless device measures signals transmitted on the second subset of beams. The beam is from a set of beams of a first type or from a set of beams of a second type. The wireless device measures the signal in a time window. The wireless device inputs the measurement results to the computational model. The wireless device receives a prediction of channel measurements for the first subset of beams from the computational model.

Description

Spatial and frequency domain beam management using time sequence information

Cross Reference to Related Applications

The present application claims the benefit of U.S. provisional application No.63/376,614, entitled "SPATIOTEMPORAL DOMAIN BEAM MANAGEMENT USING TIME SERIESDATA", filed 22 at 9, 2022, U.S. provisional application No.63/376,615, entitled "FREQUENCY DOMAIN BEAM MANAGEMENT USING TIME SERIES", filed 22 at 9, 2022, and U.S. patent application No.18/369,488, filed 18 at 9, 2023, which are expressly incorporated herein by reference in their entirety.

Technical Field

The present invention relates generally to communication systems and, more particularly, to techniques for spatial and frequency domain beam management using time sequence information.

Background

The statements in this section merely provide background information related to the present disclosure and may not constitute prior art.

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

These multiple access techniques have been employed in various telecommunications standards to provide a common protocol that enables different wireless devices to communicate at the urban, national, regional, and even global levels. An example telecommunications standard is the 5G New Radio (NR). The 5G NR is part of a continuous mobile broadband evolution promulgated by the third generation partnership project (Third Generation Partnership Project,3 GPP) to meet new requirements associated with latency, reliability, security, scalability (e.g., with the internet of things (Internet of Things, ioT)) and other requirements. Some aspects of 5G NR may be based on the 4G long term evolution (Long Term Evolution, LTE) standard. Further improvements in the 5G NR technology are needed. These improvements are also applicable to other multiple access techniques and telecommunication standards employing these techniques.

Disclosure of Invention

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, and is intended to neither identify key or critical elements of all aspects nor delineate 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 one aspect of the invention, a method, computer-readable medium, and apparatus are provided. The apparatus may be a wireless device. The wireless device selects a first subset of beams to be used for beam management. The beam is from a set of first type beams used for communication with a base station or UE. The wireless device measures signals transmitted on the second subset of beams. The beam is from a set of beams of a first type or from a set of beams of a second type. The wireless device measures the signal in a time window. The wireless device inputs the measurement results to the computational model. The wireless device receives a prediction of channel measurements for the first subset of beams from the computational model.

To the accomplishment of the foregoing and related ends, one or more aspects comprise the features hereinafter fully described and particularly pointed out in the claims. The following description and the annexed 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 and the description is intended to include all such aspects and their equivalents.

Drawings

Fig. 1 is a schematic diagram illustrating an example of a wireless communication system and an access network.

Fig. 2 is a schematic diagram illustrating a base station communicating with a UE in an access network.

Fig. 3 illustrates an example logical architecture of a distributed access network.

Fig. 4 illustrates an example physical architecture of a distributed access network.

Fig. 5 is a diagram showing an example of a DL-centric time slot.

Fig. 6 is a diagram illustrating an example of UL-centric time slots.

Fig. 7 is a schematic diagram illustrating machine learning based spatial domain beam prediction.

Fig. 8 is a schematic diagram showing cross frequency (cross frequency) beam prediction based on machine learning.

Fig. 9 is a flow chart of a method (process) for predicting channel measurements on a beam.

Detailed Description

The detailed description set forth below in connection with the appended drawings is intended as a description of various configurations and is not intended to 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 the various concepts. It will be apparent, however, to one skilled in the art that the 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.

Aspects of a telecommunications system will now be presented with reference to various apparatus and methods. These apparatus and methods will be described in the following detailed description and illustrated in the figures 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.

As an example, an element or any portion of an element or any combination of elements may be implemented as a "processing system" comprising one or more processors. Examples of processors include microprocessors, microcontrollers, graphics processing units (graphics processing unit, GPU), central processing units (central processing unit, CPU), application processors, digital signal processors (digital signal processor, DSP), reduced instruction set computing (reduced instruction set computing, RISC) processors, system-on-chip (systems on a chip, soC), baseband processors, field programmable gate arrays (field programmable gate array, FPGA), programmable logic devices (programmable logic device, PLD), state machines, gating logic, discrete hardware circuits, and other suitable hardware configured to perform the various functions described throughout this disclosure. One or more processors in the processing system may execute the software. Software should be construed broadly to mean instructions, instruction sets, code segments, program code, programs, subroutines, software components, applications, software packages, routines, subroutines, objects, executables, threads of execution, procedures, functions, and the like, whether referred to as software, firmware, middleware, microcode, hardware description language, or other language.

Thus, in one or more example aspects, 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. A storage media may be any available media that can be accessed by a computer. By way of example, and not limitation, such computer-readable media can comprise random-access memory (RAM), read-only memory (ROM), electrically erasable programmable ROM (electrically erasable programmable ROM), optical disk storage, magnetic disk storage, other magnetic storage devices, combinations of the above-described types of computer-readable media, or any other media that can be used to store computer-executable code in the form of instructions or data structures that can be accessed by a computer.

Fig. 1 is a schematic diagram illustrating an example of a wireless communication system and an access network 100. A wireless communication system, also referred to as a wireless wide area network (wireless wide area network, WWAN), includes a base station 102, a UE 104, an evolved packet core (Evolved Packet Core, EPC) 160, and another core network 190 (e.g., a 5G core (5G c)). Base station 102 may include a macrocell (high power cellular base station) and/or a small cell (low power cellular base station). The macrocell includes a base station. Small cells include femto cells, pico cells, and micro cells.

A base station 102 configured for 4G LTE, collectively referred to as an evolved universal mobile telecommunications system (Universal Mobile Telecommunications System, UMTS) terrestrial radio access network (Evolved Universal Mobile Telecommunications System Terrestrial Radio Access Network, E-UTRAN), may interface with EPC 160 over a backhaul link 132 (e.g., SI interface). A base station 102 configured for 5G NR (collectively referred to as Next Generation RAN (NG-RAN)) may interface with a core network 190 through a backhaul link 184. Among other functions, the base station 102 may perform one or more of the following functions: user data transfer, radio channel encryption and decryption, integrity protection, header compression, mobility control functions (e.g., handover, dual connectivity), inter-cell interference coordination, connection establishment and release, load balancing, non-access stratum (NAS) message allocation, NAS node selection, synchronization, radio access network (radio access network, RAN) sharing, multimedia broadcast multicast services (multimedia broadcast multicast service, MBMS), subscriber and device tracking, RAN information management (RAN information management, RIM), paging, positioning, and delivery of alert messages. Base stations 102 may communicate with each other directly or indirectly (e.g., through EPC 160 or core network 190) over backhaul link 134 (e.g., an X2 interface). The backhaul link 134 may be wired or wireless.

The base station 102 may communicate wirelessly with the UE 104. Each base station 102 may provide communication coverage for a respective geographic coverage area 110. There may be overlapping geographic coverage areas 110. For example, the small cell 102 'may have a coverage area 110' that overlaps with the coverage area 110 of one or more macro base stations 102. A network comprising both small cells and macro cells may be referred to as a heterogeneous network. The heterogeneous network may also include a home Evolved Node B (eNB) (Home Evolved Node B, heNB) that may provide services to a restricted group called a closed subscriber group (closed subscriber group, CSG). The communication link 120 between the base station 102 and the UE 104 may include Uplink (UL) (also known as reverse link) transmissions from the UE 104 to the base station 102 and/or Downlink (DL) (also known as forward link) transmissions from the base station 102 to the UE 104. Communication link 120 may use multiple-input multiple-output (MIMO) antenna techniques including spatial multiplexing, beamforming, and/or transmit diversity. The communication link may be through one or more carriers. The base station 102/UE 104 may use a spectrum up to 7MHz (e.g., 5, 10, 15, 20, 100, 400, etc.) bandwidth per carrier in each direction, the component carriers being allocated in carrier aggregation up to a total yxmhz (x component carriers) for transmission. 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., DL may be allocated more or less carriers than UL). The component carriers may include a primary component carrier and one or more secondary component carriers. The primary component carrier may be referred to as a primary cell (PCell), and the secondary component carrier may be referred to as a secondary cell (SCell).

Some UEs 104 may communicate with each other using a device-to-device (D2D) communication link 158. The D2D communication link 158 may use the DL/UL WWAN spectrum. The D2D communication link 158 may use one or more sidelink channels, such as a physical sidelink broadcast channel (physical sidelink broadcast channel, PSBCH), a physical sidelink discovery channel (physical sidelink discovery channel, PSDCH), a physical sidelink shared channel (physical sidelink shared channel, PSSCH), and a physical sidelink control channel (physical sidelink control channel, PSCCH). D2D communication may be through various wireless D2D communication systems such as, for example, flashLinQ, wiMedia, bluetooth, zigBee, wi-Fi based on the IEEE 802.11 standard, LTE, or NR.

The wireless communication system may also include a Wi-Fi Access Point (AP) 150 that communicates with a Wi-Fi Station (STA) 152 via a communication link 154 in the 5GHz unlicensed spectrum. When communicating in the unlicensed spectrum, STA 152/AP 150 may perform a clear channel assessment (clear channel assessment, CCA) prior to communication to determine whether a channel is available.

The small cell 102' may operate in licensed and/or unlicensed spectrum. When operating in unlicensed spectrum, the small cell 102' may employ NR and use the same 5GHz unlicensed spectrum as used by Wi-Fi AP 150. The use of NR small cells 102' in the unlicensed spectrum may improve coverage of the access network and/or increase capacity of the access network.

Base station 102, whether a small cell 102' or a large cell (e.g., macro base station), may comprise an eNB, a gndeb (gNB), or another type of base station. Some base stations, such as the gNB 180, may operate in the legacy sub-6 GHz spectrum, millimeter wave (mmW) frequencies, and/or near mmW frequencies in communication with the UE 104. When the gNB 180 operates in mmW or near mmW frequencies, the gNB 180 may be referred to as a mmW base station. The extremely high frequency (extremely high frequency, EHF) is part of the RF in the electromagnetic spectrum. EHF has a wavelength in the range of 30GHz to 300GHz and between 1 mm and 10 mm. The radio waves in the frequency band may be referred to as millimeter waves. The near mmW may extend down to a frequency of 3GHz and a wavelength of 100 millimeters. The ultra-high frequency (super high frequency, SHF) band extends between 3GHz and 30GHz, also known as centimetre waves. Communications using mmW/near mmW radio bands (e.g., 3GHz-300 GHz) have extremely high path loss and short distances. The mmW base station 180 may utilize beamforming 182 with the UE 104 to compensate for extremely high path loss and short distances.

The base station 180 may transmit the beamformed signals to the UE 104 in one or more transmit directions 108 a. The UE 104 may receive the beamformed signals from the base station 180 in one or more receive directions 108 b. The UE 104 may also transmit the beamformed signals in one or more transmit directions to the base station 180. The base station 180 may receive the beamformed signals from the UEs 104 in one or more directions. The base stations 180/UEs 104 may perform beam training to determine the optimal receive direction and transmit direction for each base station 180/UE 104. The transmission direction and the reception direction of the base station 180 may be the same or different. The transmission direction and the reception direction of the UE 104 may be the same or different.

EPC 160 may include a mobility management entity (Mobility Management Entity, MME) 162, other MMEs 164, a serving gateway 166, a multimedia broadcast multicast service (Multimedia Broadcast Multicast Service, MBMS) gateway 168, a broadcast multicast service center (Broadcast Multicast Service Center, BM-SC) 170, and a packet data network (Packet Data Network, PDN) gateway 172.MME 162 may communicate with home subscriber server (Home Subscriber Server, HSS) 174. The MME 162 is a control node that handles signaling between the UE 104 and the EPC 160. Generally, MME 162 provides bearer and connection management. All user Internet Protocol (IP) packets are transmitted through the serving gateway 166, which serving gateway 166 itself is connected to the PDN gateway 172. The PDN gateway 172 provides UE IP address allocation as well as other functions. The PDN gateway 172 and BM-SC 170 are connected to an IP service 176.IP services 176 may include the internet, intranets, IP multimedia subsystem (IP Multimedia Subsystem, IMS), PS streaming services, and/or other IP services. The BM-SC 170 may provide functionality for MBMS user service provisioning and delivery. The BM-SC 170 may be used as an entry point for content provider MBMS transmissions, may be used to authorize and initiate MBMS bearer services within a public land mobile network (public land mobile network, PLMN), and may be used to schedule MBMS transmissions. The MBMS gateway 168 may be used to allocate MBMS traffic to base stations 102 belonging to a multicast broadcast single frequency network (Multicast Broadcast Single Frequency Network, MBSFN) area broadcasting a particular service and may be responsible for session management (start/stop) and for collecting eMBMS related charging information.

The core network 190 may include access and mobility management functions (Access and Mobility Management Function, AMF) 192, other AMFs 193, location management functions (location management function, LMF) 198, session management functions (Session Management Function, SMF) 194, and user plane functions (User Plane Function, UPF) 195. The AMF 192 may communicate with a unified data management (Unified Data Management, UDM) 196. The AMF 192 is a control node that handles signaling between the UE 104 and the core network 190. In general, SMF 194 provides QoS flows and session management. All user internet protocol (Internet protocol, IP) packets are transmitted through the UPF 195. The UPF 195 provides UE IP address assignment as well as other functions. The UPF 195 is connected to an IP service 197. The IP services 197 may include the internet, intranets, IP multimedia subsystems (IP Multimedia Subsystem, IMS), PS streaming services, and/or other IP services.

A base station may also be called a gNB, a Node B, an evolved Node B (eNB), an access point, a base transceiver station, a radio base station, a radio transceiver, a transceiver function, a basic service set (basic service set, BSS), an extended service set (extended service set, ESS), a transmission and reception point (transmit reception point, TRP), or some other suitable terminology. The base station 102 provides an access point for the UE 104 to the EPC 160 or the core network 190. Examples of UEs 104 include a cellular telephone, a smart phone, a session initiation protocol (session initiation protocol, SIP) phone, a laptop, a personal digital assistant (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 computer, a smart device, a wearable device, a vehicle, an electricity meter, an air pump, a large or small kitchen appliance, a healthcare device, an implant, a sensor/actuator, a display, or any other similar functional device. Some UEs 104 may be referred to as IoT devices (e.g., parking timers, air pumps, toasters, vehicles, heart monitors, etc.). The UE 104 may also be referred to as a station, mobile station, subscriber station, mobile unit, subscriber unit, wireless unit, remote unit, mobile device, wireless communication device, remote device, mobile subscriber station, access terminal, mobile terminal, wireless terminal, remote terminal, handset, user agent, mobile client, or some other suitable terminology.

Although the invention may refer to a 5G New Radio (NR), the invention is applicable to other similar areas such as LTE, LTE-Advanced (LTE-a), code Division Multiple Access (CDMA), global system for mobile communications (GSM), or other wireless/radio access technologies.

Fig. 2 is a block diagram of a base station 210 in communication with a UE 250 in an access network. In DL, IP packets from EPC 160 may be provided to controller/processor 275. Controller/processor 275 implements layer 3 and layer 2 functions. Layer 3 includes a radio resource control (radio resource control, RRC) layer, and layer 2 includes a packet data convergence protocol (packet data convergence protocol, PDCP) layer, a Radio Link Control (RLC) layer, and a medium access control (medium access control, MAC) layer. Controller/processor 275 provides: RRC layer functions associated with broadcast 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 (radio access technology, RAT) mobility, and measurement configuration for UE measurement reporting; PDCP layer functions associated with header compression/decompression, security (ciphering, deciphering, integrity protection, integrity verification) and handover support functions; RLC layer functions associated with transmission of upper layer Packet Data Units (PDUs), error correction by ARQ, concatenation, segmentation and reassembly of RLC service data units (service data unit, SDU), re-segmentation of RLC data PDUs and reordering of RLC data PDUs; and MAC layer functions 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 by HARQ, priority handling and logical channel prioritization.

A Transmit (TX) processor 216 and a Receive (RX) processor 270 implement layer 1 functions 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 (forward error correction, FEC) encoding/decoding of the transport channel, interleaving, rate matching, mapping on the physical channel, modulation/demodulation of the physical channel, and MIMO antenna processing. TX processor 216 processes the 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-quadrature amplitude modulation, M-QAM)). The coded and modulated symbols may then be split into parallel streams. Each stream may then be mapped to OFDM subcarriers, multiplexed with reference signals (e.g., pilots) in the time and/or frequency domain, and then combined together using an inverse fast fourier transform (Inverse Fast Fourier Transform, IFFT) to produce a physical channel carrying the time domain OFDM symbol stream. The OFDM streams are spatially precoded to produce a plurality of spatial streams. The channel estimates from the channel estimator 274 may be used to determine coding and modulation schemes and for spatial processing. The channel estimate may be derived from a reference signal and/or channel condition feedback transmitted by the UE 250. Each spatial stream may then be provided to a different antenna 220 via a separate transmitter 218 TX. Each transmitter 218TX may modulate an RF carrier with a respective spatial stream for transmission.

At the UE 250, each receiver 254RX receives a signal through its respective antenna 252. Each receiver 254RX recovers information modulated onto an RF carrier and provides the information to a Receive (RX) processor 256.TX processor 268 and RX processor 256 implement layer 1 functions associated with various signal processing functions. RX processor 256 may perform spatial processing on the information to recover any spatial streams destined for UE 250. If multiple spatial streams are destined for UE 250, they may be combined into a single OFDM symbol stream by RX processor 256. The RX processor 256 then converts the OFDM symbol stream from the time domain to the frequency domain using a fast fourier transform (Fast Fourier Transform, FFT). The frequency domain signal comprises a separate OFDM symbol stream for each subcarrier of the OFDM signal. The symbols and reference signals on each subcarrier are recovered and demodulated by determining the most likely signal constellation points transmitted by base station 210. These soft decisions may be based on channel estimates computed by channel estimator 258. The soft decisions are then decoded and deinterleaved to recover the data and control signals that were originally transmitted by the base station 210 on the physical channel. The data and control signals are then provided to a controller/processor 259 that implements layer 3 and layer 2 functions.

The controller/processor 259 can be associated with a memory 260 that stores program codes and data. Memory 260 may be referred to as a computer-readable medium. In the UL, the controller/processor 259 provides demultiplexing between transport and logical channels, packet reassembly, deciphering, header decompression, and control signal processing to recover IP packets from the EPC 160. The controller/processor 259 is also responsible for error detection using ACK and/or NACK protocols to support HARQ operations.

Similar to the functionality described in connection with DL transmissions by the base station 210, the controller/processor 259 provides RRC layer functions associated with system information (e.g., MIB, SIB) acquisition, RRC connection, and measurement reporting; PDCP layer functions associated with header compression/decompression and security (ciphering, deciphering, integrity protection, integrity verification); RLC layer functions associated with upper layer PDU delivery, error correction by ARQ, concatenation, segmentation and reassembly of RLC SDUs, re-segmentation of RLC data PDUs, and reordering of RLC data PDUs; and MAC layer functions 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 by HARQ, priority handling and logical channel prioritization.

TX processor 268 may use channel estimation results from the reference signals or feedback transmitted by base station 210 by channel estimator 258 to select the appropriate coding and modulation scheme and facilitate spatial processing. The spatial streams generated by TX processor 268 may be provided to different antennas 252 via separate transmitters 254 TX. Each transmitter 254TX may modulate an RF carrier with a respective spatial stream for transmission. UL transmissions are processed at base station 210 in a manner similar to that described in connection with the receiver functionality at UE 250. Each receiver 218RX receives a signal through its corresponding antenna 220. Each receiver 218RX recovers information modulated onto an RF carrier and provides the information to the RX processor 270.

The controller/processor 275 may be associated with a memory 276 that stores program codes and data. Memory 276 may be referred to as a computer-readable medium. In the UL, the controller/processor 275 provides demultiplexing between transport and logical channels, packet reassembly, deciphering, header decompression, control signal processing to recover IP packets from the UE 250. IP packets from controller/processor 275 may be provided to EPC 160. The controller/processor 275 is also responsible for error detection using ACK and/or NACK protocols to support HARQ operations.

A New Radio (NR) may refer to a radio configured to operate according to a new air interface (e.g., other than an orthogonal frequency division multiple access (Orthogonal Frequency Divisional Multiple Access, OFDMA) based air interface) or a fixed transport layer (e.g., other than Internet Protocol (IP)). NR may utilize OFDM with Cyclic Prefix (CP) on uplink and downlink and may include support for half-duplex operation using time division duplex (time division duplexing, TDD). NR may include critical tasks targeting enhanced mobile broadband (Enhanced Mobile Broadband, eMBB) services with a wide bandwidth (e.g., over 80 MHz), millimeter waves (mmW) targeting high carrier frequencies (e.g., 60 GHz), massive MTC (emtc) targeting non-backward compatible MTC technologies, and/or ultra-reliable low latency communication (ultra-reliable low latency communication, URLLC) services.

A single component carrier bandwidth of 100MHz may be supported. In one example, an NR Resource Block (RB) may span 12 subcarriers with a subcarrier bandwidth of 60kHz within a 0.25ms duration or a bandwidth of 30kHz within a 0.5ms duration (similarly, a 50MHz BW of 15kHz SCS within a 1ms duration). Each radio frame may consist of 10 subframes (10, 20, 40 or 80 NR slots) of length 10 ms. Each slot may indicate a link direction (i.e., DL or UL) for data transmission, and the link direction of each slot may be dynamically switched. Each slot may include DL/UL data and DL/UL control data. UL and DL slots for NR may be described in more detail below with respect to fig. 5 and 6.

The NR RAN may include a Central Unit (CU) and a Distributed Unit (DU). An NR BS (e.g., a gNB, a 5G node B, a transmission and reception point (transmission reception point, TRP), an Access Point (AP)) may correspond to one or more BSs. An NR cell may be configured as an access cell (ACell) or a data only cell (DCell). For example, the RAN (e.g., a central unit or a distributed unit) may configure the cells. The DCell may be a cell for carrier aggregation or dual connectivity, and may not be used for initial access, cell selection/reselection, or handover. In some cases, the DCell may not transmit a synchronization signal (synchronization signal, SS), and in some cases, the DCell may transmit the SS. The NR BS may transmit a downlink signal indicating a cell type to the UE. Based on the cell type indication, the UE may communicate with the NR BS. For example, the UE may determine an NR BS considering cell selection, access, handover, and/or measurement based on the indicated cell type.

Fig. 3 illustrates an example logical architecture of a distributed RAN 300 in accordance with aspects of the present invention. The 5G access node 306 may include an access node controller (access node controller, ANC) 302. The ANC may be a Central Unit (CU) of the distributed RAN. The backhaul interface to the next generation core network (next generation core network, NG-CN) 304 may terminate at the ANC. The backhaul interface to the neighboring next generation access node (next generation access node, NG-AN) 310 may terminate at the ANC. ANC may include one or more TRP 308 (which may also be referred to as BS, NR BS, nodeb, 5G NB, AP, or some other terminology). As described above, TRP may be used interchangeably with "cell".

TRP 308 may be a Distributed Unit (DU). TRP may be connected to one ANC (ANC 302) or more than one ANC (not shown). For example, for RAN sharing, radio as a service (radio as a service, raaS), and service specific ANC deployments, TRP may be connected to more than one ANC. The TRP may include one or more antenna ports. The TRP may be configured to provide services to the UE either individually (e.g., dynamic selection) or jointly (e.g., joint transmission).

The local architecture of the distributed RAN 300 may be used to illustrate the forwarding definition. An architecture may be defined that supports a forward-drive solution across different deployment types. For example, the architecture may be based on transmit network capabilities (e.g., bandwidth, latency, and/or jitter). The architecture may share functionality and/or components with LTE. According to aspects, a next generation AN (NG-AN) 310 may support dual connectivity with NR. The NG-AN may share common preambles for LTE and NR.

The architecture may enable collaboration between and among TRPs 308. For example, there may be collaboration within the TRP and/or across TRP via ANC 302. According to aspects, there may be no need/presence of an interface between TRPs.

According to aspects, dynamic configuration of split logic functions may exist within the architecture of the distributed RAN 300. The PDCP, RLC, MAC protocol may be adaptively placed at ANC or TRP.

Fig. 4 illustrates an example physical architecture of a distributed RAN 400 in accordance with aspects of the invention. The centralized core network element (centralized core network unit, C-CU) 402 may host core network functions. The C-CU may be centrally deployed. The C-CU functions may be offloaded (e.g., to an advanced wireless service (advanced wireless service, AWS)) in an effort to handle peak capacity. The centralized RAN unit (centralized RAN unit, C-RU) 404 may host one or more ANC functions. Alternatively, the C-RU may host the core network functions locally. The C-RU may have a distributed deployment. The C-RU may be closer to the network edge. Distributed Units (DUs) 406 may host one or more TRPs. The DUs may be located at the edge of a Radio Frequency (RF) enabled network.

Fig. 5 is a diagram 500 illustrating an example of DL-centric time slots. The DL-centric time slot may comprise a control portion 502. The control portion 502 may be present in the beginning or beginning portion of the DL-centric time slot. The control portion 502 may include various scheduling information and/or control information corresponding to various portions of the DL-centric time slot. In some configurations, the control portion 502 may be a Physical DL Control Channel (PDCCH), as shown in fig. 5. The DL-centric time slot may also include a DL data portion 504.DL data portion 504 may sometimes be referred to as the payload of a DL-centric time slot. The DL data portion 504 may include communication resources for transmitting DL data from a scheduling entity (e.g., UE or BS) to a subordinate entity (e.g., UE). In some configurations, DL data portion 504 may be a Physical DL Shared Channel (PDSCH).

DL-centric time slots may also include a common UL portion 506. The common UL portion 506 may sometimes be referred to as a UL burst, a common UL burst, and/or various other suitable terms. The common UL portion 506 may include feedback information corresponding to various other portions of the DL-centric time slot. For example, the common UL portion 506 may include feedback information corresponding to the control portion 502. Non-limiting examples of feedback information may include an ACK signal, a NACK signal, a HARQ indicator, and/or various other suitable types of information. The common UL portion 506 may include additional or alternative information, such as information related to random access channel (random access channel, RACH) procedures, scheduling requests (scheduling request, SR), and various other suitable types of information.

As shown in fig. 5, the end of DL data portion 504 may be separated in time from the beginning of common UL portion 506. This time separation may sometimes be referred to as a gap, guard period, guard interval, and/or various other suitable terms. The separation provides time from DL communication (e.g., a receiving operation of a subordinate entity (e.g., UE)) to UL communication (e.g., a transmission of a subordinate entity (e.g., UE)) for handover. Those of ordinary skill in the art will appreciate that the foregoing is merely one example of DL-centric time slots and that alternative structures may exist having similar features without necessarily departing from aspects described herein.

Fig. 6 is a diagram 600 illustrating an example of UL-centric time slots. The UL-centric time slot may comprise a control portion 602. The control portion 602 may be present in the beginning or beginning portion of the UL-centric time slot. The control portion 602 in fig. 6 may be similar to the control portion 502 described above with reference to fig. 5. UL-centric time slots may also include UL data portion 604.UL data portion 604 may sometimes be referred to as the payload of a UL-centric time slot. The UL portion may refer to communication resources for transmitting UL data from a subordinate entity (e.g., UE) to a scheduling entity (e.g., UE or BS). In some configurations, the control portion 602 may be a Physical DL Control Channel (PDCCH).

As shown in fig. 6, the end of the control portion 602 may be separated in time from the beginning of the UL data portion 604. This time separation may sometimes be referred to as a gap, guard period, guard interval, and/or various other suitable terms. This separation provides time for switching from DL communication (e.g., a receive operation by the scheduling entity) to UL communication (e.g., a transmission by the scheduling entity). UL-centric time slots may also include a common UL portion 606. The common UL portion 606 in fig. 6 may be similar to the common UL portion 506 described above with reference to fig. 5. Additionally or alternatively, the common UL portion 606 may include information related to channel quality indicators (channel quality indicator, CQI), sounding reference signals (sounding reference signal, SRS), and various other suitable types of information. Those of ordinary skill in the art will appreciate that the foregoing is merely one example of UL-centric time slots, and that alternative structures may exist that have similar features without necessarily departing from the aspects described herein.

In some cases, two or more subordinate entities (e.g., UEs) may communicate with each other using side-downlink signals. Real world applications for such side-link communications may include public safety, proximity services, UE-to-network relay, vehicle-to-vehicle (V2V) communications, internet of things (Internet of Everything, ioE) communications, ioT communications, mission critical grids, and/or various other suitable applications. In general, a side-downlink signal may refer to a signal transmitted from one subordinate entity (e.g., UE 1) to another subordinate entity (e.g., UE 2) without relaying the communication through a scheduling entity (e.g., UE or BS), even though the scheduling entity may be used for scheduling and/or control purposes. In some examples, the side-uplink signal may be transmitted using a licensed spectrum (as opposed to a wireless local area network that typically uses an unlicensed spectrum).

Fig. 7 is a schematic diagram illustrating machine learning based spatial domain beam prediction. In this example, the base station 702 transmits beams 711 to 734 simultaneously in various directions. After identifying the incoming beams, the UE 704 may calculate an L1-RSRP for each beam. L1-RSRP is the average received signal power per resource element measured on the resource elements carrying the secondary synchronization signal or CSI-RS.

Machine learning algorithms are used to analyze the history of signal strengths from a subset of beams and attempt to find patterns or trends in the data. This helps predict the signal strength of the remaining unmeasured beams. By identifying patterns in the historical data from the subset of beams, the algorithm can predict the signal strengths of other beams even while the UE is moving.

In this example, the base station 702 is equipped with multiple antennas and has the ability to transmit 24 different beams 711 to 734 simultaneously in various directions. The UE 704, which is moving from time to time, is equipped with its own antenna and periodically measures channel metrics (such as RSRP) of a strategically selected subset of the 4 beams (e.g., beams 715, 716, 729, and 730) sent by the base station.

The measurements collected from these 4 beams are saved as historical data over time. The historical data captures channel metrics of the subset of beams over time, drawing a dynamic portrait of the UE 704's interactions with those beams. The UE 704 may be configured with a historical data time window 760 during which measurements are stored at the UE 704. In this example, the current time is t ₀ . Historical data time window 760 is from time t _-3 By time t ₀ . The measurement data of a subset of beams 715, 716, 729 and 730, and measurement data obtained during the historical data time window 760, are stored at the UE 704 and used as inputs to the AI/ML model 750 to predict the current time t ₀ Measurement of unmeasured beam and at future time t ₁ 、t ₂ Is a function of the measurements of all beams of the beam.

The historical data is used as an input to a machine learning algorithm to predict the channel metrics of the unmeasured beams, thereby guiding the UE 704 as to which beam it is focusing on when it needs to communicate with the base station 702. Thus, the algorithm can predict channel metrics for all beams based on analyzing patterns and trends in historical data from a subset of beams.

In general, another subset of beams that are not conventionally measured (e.g., beam 711, beam 721, beam 724, and beam 734) may be periodically sampled and their channel metrics recorded. This is used to verify the algorithm's predictions for real world performance, while also updating the model. Periodic measurements help with algorithm improvement by updating their weights and parameters. As machine learning algorithms mature, their predictions of optimal beams become more and more accurate. When the UE 704 initiates communication, it may select a UE transmit or receive beam 770 that may produce good signal quality (e.g., an optimal beam) based on the prediction.

The base station 702 and the UE 704 use the same AI/ML model for beam prediction. The base station 702 and the UE 704 may employ the same AI/ML model in order to establish a shared understanding of data patterns and behavior, resulting in consistent decision-making and enhanced accuracy of predictions and responses. By utilizing the same AI/ML model, the base station 702 and the UE 704 create a unified approach that improves the system's ability to efficiently manage network resources.

The method involves predicting the top k beams that may have the highest channel metrics, rather than identifying a single optimal beam. In many scenarios, focusing on the first k beams provides excellent accuracy. The prediction of the first k beams is achieved by estimating them based on the first k channel metric values. This is very consistent with real world communication requirements, thereby enhancing system performance.

Fig. 8 illustrates cross frequency beam prediction based on machine learning. The FR2 connection enables directional communication with a greater number of antenna elements and provides additional beamforming gain, which compensates for propagation losses. However, the directional link will require precise alignment of the beams at the base station 702 and the UE 704. This introduces the need for efficient management of beams, where the UE 704 and the base station 702 periodically identify the optimal beam to operate at any given point in time. The base station 802 may serve both the FR1 band and the FR2 band. The base station 802 transmits beams 820 to 825 in the FR1 band and beams 830 to 836 in the FR2 band simultaneously in various directions.

Although there is a difference between FR1 and FR2, there is similarity in array geometry, path number, and environment. Historical data from FR1 may provide insight into frequency beam management in FR2, improving performance and efficiency. Acquiring channel data in FR1 is more cost effective than acquiring channel data in FR 2. Historical data plays a key role in optimizing beam management by capturing details about UE trajectories. By utilizing historical patterns, the system can coordinate accurate beam prediction with a skilled (adept) strategy.

The UE 804 moving over time periodically measures RSRP from the beams 820 to 825. These measurements reflect the signal strength received from beams 820 through 825 at the location of the UE. The measurements are saved over time, capturing RSRP over time and depicting the UE's interaction with beam 820. The historical data enables machine learning algorithms to analyze the trajectory and movement patterns of the UE to guide beam prediction.

Periodic measurements of some FR2 beams serve two purposes: the prediction results are validated and real world data is provided to improve the algorithm. This verification cycle enhances prediction accuracy. Intermittent measurements also facilitate dynamic training, where the weights of the algorithm are updated based on the new data, allowing adaptation to environmental changes since the initial deployment.

As described above, the base station and the UE need to use the same AI/ML model. When both ends of the communication chain use the same model, it establishes a shared understanding of data patterns and behavior.

The ML model extrapolates the time constraints required to be made available for the beam selection process. Time constraint inference ensures that the beam selection process does not introduce unnecessary delays or interruptions. The faster the model predicts the optimal beam, the faster the communication link is established or adjusted, resulting in an improved user experience.

The model deployed in the UE needs to be synchronized after the UE is handed over to the target cell. By synchronizing the model after handover, the UE can utilize the latest information to make informed decisions regarding beam selection, resource allocation and interference management.

The window size should be small enough so that the history data can be stored in a cache (limited memory size). One key factor in selecting window size is the need to store historical data in the cache. The cache serves as a fast access memory location that holds frequently accessed information, which is beneficial to the overall speed and responsiveness of the system.

The entire model needs to be loaded into the chip. Furthermore, the window size should be consistent with the ability of the chip to load the entire machine learning model. The chip has a limited capacity for storing and processing data, including model parameters and associated calculations. Ensuring that the entire model can be loaded onto the chip is critical to maintaining the efficiency of model inference. A balance needs to be struck between window size and model complexity to prevent taking up chip resources and resulting in potential performance degradation. Essentially, window size should strike a fine balance between the need to store historical data in cache to achieve efficient model operation and ensuring that the complete model can be loaded onto the chip to achieve accurate and timely predictions. This deliberate consideration ensures that the machine learning system operates in an optimal manner within given memory and processing constraints, ultimately contributing to the success of the overall communication framework.

As described above, beam prediction can be performed in the base station. The UE may provide a series of basic information that significantly contributes to the beam management process. This includes details about the beam pattern, providing insight into how to configure the antenna array of the device for optimal signal reception and transmission. Information about the beam elevation angle (which indicates the angle at which the beam is directed) helps the network to accurately align the signal towards the UE. Furthermore, metrics related to the location, direction and orientation of the UE further enrich the network's understanding of the location and movement patterns of the device.

In addition, beam prediction may also be performed at the UE. The scope of UE-side beam management relates to predictions related to downlink transmit beam predictions that anticipate beams transmitting downlink data to the UE. Downlink receive beam prediction focuses on the beam at the UE that will be optimal for downlink data from the base station. The beam pair predicts a transmit beam for the downlink at the base station and its corresponding receive beam at the UE. A series of channel metrics are used as a basis for effective beam management and prediction. These metrics include a received signal reference power (Received Signal Reference Power, RSRP) value that reflects the signal strength at the UE. Channel state information (Channel State Information, CSI) is another metric that provides insight into the current state of the channel between the UE and the network. The beam angle tells how the beam is directed in space, allowing accurate beamforming. The channel quality indicator (Channel Quality Indicator, CQI) provides information about the channel quality, thereby guiding decisions related to beam selection. Together, these channel metrics permit the UE to make informed decisions about beam management.

Although fig. 7 to 8 illustrate techniques of spatial and frequency domain beam management using time sequence information by taking an example in which a UE receives a downlink beam from a base station, the same techniques may be equally applied to a base station receiving an uplink beam from a UE.

Fig. 9 is a flow chart 900 of a method (process) for predicting channel measurements on a beam. The method may be performed by a wireless device, which may be a UE or a base station (e.g., UE 704, UE 804, UE 250, base station 702, base station 802, base station 210). In operation 902, the wireless device selects a first subset of beams (e.g., beams 712, 722, 723, and 734 or beams 830, 833, and 836) to be used for beam management from a set of first type beams used for communication with a base station or UE. In operation 904, the wireless device measures signals transmitted on a second subset of beams (e.g., beams 715, 716, 729, and 730) of the set of first type beams or on a set of second type beams (e.g., beams 820, 821, 823, 824, and 825) in a time window.

In operation 906, the wireless device inputs the measurements to a computational model, which may include a machine learning model trained on historical channel measurements on the second subset of beams or on the set of second type beams. The historical measurement may include time series data captured in a time window.

In operation 908, the wireless device receives a prediction of channel measurements for the first subset of beams from the computational model. In some configurations, the predictions are measurements on a set of top k beams from a set of beams, where the set of top k beams includes k beams predicted to have optimal measurements, such as top k predicted received signal reference power (received signal reference power, RSRP) values.

In operation 910, the wireless device performs beam management based on a prediction of channel measurements. Beam management may include: one or more optimal beams for communicating with the base station are selected based on the predictions of the measurements.

In some configurations, signals transmitted on a set of second type beams are measured, wherein the set of second type beams is in a first frequency band and the set of first type beams is in a second frequency band. The first frequency band may be in FR1 and the second frequency band may be in FR 2. Historical data from FR1 may provide insight into frequency beam management in FR2, improving performance and efficiency.

In some configurations, the wireless device is a UE, and the first type of beam and the second type of beam are transmitted by the base station and received by the UE in the downlink direction. In some configurations, the wireless device is a base station, and the first type of beam and the second type of beam are transmitted by the UE and received by the base station in the uplink direction.

In operation 912, the wireless device periodically measures signals transmitted on the verified subset of beams. In operation 914, the wireless device updates the computing model based on the measurements on the verified subset of beams. Updating the computing model may include updating a subset of the weights of the computing model.

The measurement may comprise at least one of: received Signal Reference Power (RSRP), channel State Information (CSI), beam angle, or Channel Quality Indicator (CQI).

It should be understood that the specific order or hierarchy of blocks in the processes/flowcharts disclosed is an illustration of exemplary approaches. Based on 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 meant to be 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 intended to be limited to the aspects shown herein, but are to be accorded the full scope consistent with the language claims, wherein reference to an element in the singular is not intended to mean "one and only one" (unless specifically so stated), but rather "one or more". The word "exemplary" means "serving as an example, instance, or illustration" in this document. Any aspect described herein as "exemplary" is not necessarily to be construed as preferred or advantageous over other aspects. The term "some" means one or more unless specifically stated otherwise. 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, a combination 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 alone, B alone, C, A and B, A and C, B and C, or a and B and C, wherein any such combination may comprise one or more members or members of A, B or C. 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 intended to be encompassed by the claims. Furthermore, nothing disclosed herein is intended to be dedicated to the public regardless of whether such disclosure is explicitly recited in the claims. The words "module," mechanism, "" element, "" device, "etc. cannot be used in place of the word" means. Thus, unless the phrase "means" is used to expressly state the element, the claim elements should not be construed as means-plus-function.

Claims (20)

1. A method of wireless communication of a wireless device, the method comprising:

selecting a first subset of beams to be used for beam management from a set of first type beams used for communication with a base station or UE;

measuring signals transmitted on a second subset of beams in the set of first type beams or on a set of second type beams in a time window;

inputting the measurement result into a calculation model; and

a prediction of channel measurements on the first subset of beams is received from the computational model.

2. The method of claim 1, wherein beam management is performed based on the prediction of the channel measurements.

3. The method of claim 2, wherein the performing beam management comprises: one or more optimal beams for communicating with the base station are selected based on the predictions of the measurements.

4. The method of claim 1, wherein the signals transmitted on the set of second type of beams are measured, wherein the set of second type of beams is in a first frequency band, wherein the set of first type of beams is in a second frequency band.

5. The method of claim 4, wherein the first frequency band is in FR1, and wherein the second frequency band is in FR 2.

6. The method of claim 1, wherein the wireless device is a UE, wherein the first type of beam and the second type of beam are transmitted by a base station and received by the UE in a downlink direction.

7. The method of claim 1, wherein the wireless device is a base station, wherein the first type of beam and the second type of beam are transmitted by a UE and received by the base station in an uplink direction.

8. The method of claim 1, wherein the computational model comprises a machine learning model trained on historical channel measurements on the second subset of beams or on the set of second type of beams.

9. The method of claim 8, wherein the historical channel measurements comprise time series data captured in the time window.

10. The method of claim 1, the method further comprising:

periodically measuring signals transmitted on the validated subset of beams; and

the computational model is updated based on the measurements on the validated subset of beams.

11. The method of claim 10, wherein updating the computing model comprises updating a subset of weights of the computing model.

12. The method of claim 1, wherein the measurement comprises at least one of: received Signal Reference Power (RSRP), channel State Information (CSI), beam angle, or Channel Quality Indicator (CQI).

13. The method of claim 1, wherein the prediction is a measurement on a set of top k beams from the set of first type beams, wherein the set of top k beams includes k beams predicted to have an optimal measurement.

14. The method of claim 13, wherein the set of top k beams is determined based on beams having top k predicted Received Signal Reference Power (RSRP) values.

15. The method of claim 1, the method further comprising: a beam for communicating with the base station is selected based on the received predictions.

16. An apparatus for wireless communication, the apparatus being a wireless device, the apparatus comprising:

a memory; and

at least one processor coupled to the memory and configured to:

Selecting a first subset of beams to be used for beam management from a set of first type beams used for communication with a base station;

measuring signals transmitted on a second subset of beams in the set of first type beams or on a set of second type beams in a time window;

inputting the measurement result into a calculation model; and

a prediction of channel measurements on the first subset of beams is received from the computational model.

17. The apparatus of claim 16, in which the at least one processor is further configured: beam management is performed based on the prediction of the channel measurements.

18. The apparatus of claim 17, wherein to perform the beam management, the at least one processor is further configured to: one or more optimal beams for communicating with the base station are selected based on the predictions of the measurements.

19. The apparatus of claim 16, wherein the signals transmitted on the set of second type of beams are measured, wherein the set of second type of beams is in a first frequency band, wherein the first subset of beams is in a second frequency band.

20. A computer-readable medium storing computer-executable code for wireless communication of a wireless device, the computer-readable medium comprising code for:

selecting a first subset of beams to be used for beam management from a set of first type beams used for communication with a base station;

measuring signals transmitted on a second subset of beams in the set of first type beams or on a set of second type beams in a time window;

inputting the measurement result into a calculation model; and

a prediction of channel measurements on the first subset of beams is received from the computational model.