WO2022041111A1

WO2022041111A1 - Methods and apparatus for hierarchical beam procedures

Info

Publication number: WO2022041111A1
Application number: PCT/CN2020/112066
Authority: WO
Inventors: Li Tan; Chaofeng HUI; Meng Liu; Ying Wang; Xuesong Chen; Haichao SONG; Liang Xue
Original assignee: Qualcomm Incorporated
Priority date: 2020-08-28
Filing date: 2020-08-28
Publication date: 2022-03-03

Abstract

The present disclosure relates to methods and devices for wireless communication including an apparatus, e.g., a UE, a cell, and/or a base station. In one aspect, the apparatus may determine a beam management procedure for the cell, the beam management procedure including at least one of a static beam procedure or a hierarchical beam procedure. The apparatus may also configure at least one beam table based on the beam management procedure, the at least one beam table corresponding to at least one of the static beam procedure or the hierarchical beam procedure. Additionally, the apparatus may select at least one beam based on a beam ID of the at least one beam, the beam ID associated with the at least one beam table. The apparatus may also transmit the at least one selected beam based on the beam ID associated with the at least one beam table.

Description

METHODS AND APPARATUS FOR HIERARCHICAL BEAM PROCEDURES

BACKGROUND Technical Field

The present disclosure relates generally to communication systems, and more particularly, to beam transmission procedures in wireless communication systems.

Introduction

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 (pc) 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.

SUMMARY

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 an aspect of the disclosure, a method, a computer-readable medium, and an apparatus are provided. The apparatus may be a cell or a base station. The apparatus may determine a beam management procedure for the cell, the beam management procedure including at least one of a static beam procedure or a hierarchical beam procedure. The apparatus may also configure at least one beam table based on the beam management procedure, the at least one beam table corresponding to at least one of the static beam procedure or the hierarchical beam procedure. The apparatus may also select at least one beam based on a beam identifier (ID) of the at least one beam, the beam ID associated with the at least one beam table. Further, the apparatus may configure the at least one selected beam based on the beam ID of the at least one beam. The apparatus may also send the beam ID of the at least one beam to at least one antenna when the at least one beam is selected. The apparatus may also transmit the at least one selected beam based on the beam ID associated with the at least one beam table. Moreover, the apparatus may switch or maintain the at least one beam based on the beam ID associated with the at least one beam table. The apparatus may also receive feedback from at least one user equipment (UE) , where the feedback may correspond to at least one of a UE position, a UE velocity, or an interference measurement.

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 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 this description is intended to include all such aspects and their equivalents.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a diagram illustrating an example of a wireless communications system and an access network.

FIG. 2A is a diagram illustrating an example of a first frame, in accordance with various aspects of the present disclosure.

FIG. 2B is a diagram illustrating an example of DL channels within a subframe, in accordance with various aspects of the present disclosure.

FIG. 2C is a diagram illustrating an example of a second frame, in accordance with various aspects of the present disclosure.

FIG. 2D is a diagram illustrating an example of UL channels within a subframe, in accordance with various aspects of the present disclosure.

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

FIG. 4 is a diagram illustrating example beam transmissions.

FIG. 5 is a diagram illustrating an example beam table in accordance with one or more techniques of the present disclosure.

FIGs. 6A, 6B, and 6C are diagrams illustrating an example beam table in accordance with one or more techniques of the present disclosure.

FIG. 7 is a diagram illustrating example communication between a UE and a cell in accordance with one or more techniques of the present disclosure.

FIG. 8 is a flowchart of a method of wireless communication.

FIG. 9 is a diagram illustrating an example of a hardware implementation for an example apparatus.

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 various concepts. However, it will be apparent to those skilled in the art that 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 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 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 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, etc., whether referred to as software, firmware, middleware, microcode, hardware description language, or otherwise.

Accordingly, in one or more example embodiments, 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, and not limitation, 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 aforementioned 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.

FIG. 1 is a diagram illustrating an example of a wireless communications system and an access network 100. The wireless communications system (also referred to as a wireless wide area network (WWAN) ) includes base stations 102, UEs 104, an Evolved Packet Core (EPC) 160, and another core network 190 (e.g., a 5G Core (5GC) ) . The base stations 102 may include macrocells (high power cellular base station) and/or small cells (low power cellular base station) . The macrocells include base stations. The small cells include femtocells, picocells, and microcells.

The base stations 102 configured for 4G LTE (collectively referred to as Evolved Universal Mobile Telecommunications System (UMTS) Terrestrial Radio Access Network (E-UTRAN) ) may interface with the EPC 160 through first backhaul links 132 (e.g., S1 interface) . The base stations 102 configured for 5G NR (collectively referred to as Next Generation RAN (NG-RAN) ) may interface with core network 190 through second backhaul links 184. In addition to other functions, the base stations 102 may perform one or more of the following functions: transfer of user data, radio channel ciphering and deciphering, integrity protection, header compression, mobility control functions (e.g., handover, dual connectivity) , inter-cell interference coordination, connection setup and release, load balancing, distribution for non-access stratum (NAS) messages, NAS node selection, synchronization, radio access network (RAN) sharing, multimedia broadcast multicast service (MBMS) , subscriber and equipment trace, RAN information management (RIM) , paging, positioning, and delivery of warning messages. The base stations 102 may communicate directly or indirectly (e.g., through the EPC 160 or core network 190) with each other over third backhaul links 134 (e.g., X2 interface) . The first backhaul links 132, the second backhaul links 184, and the third backhaul links 134 may be wired or wireless.

The base stations 102 may wirelessly communicate with the UEs 104. Each of the base stations 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 the coverage area 110 of one or more macro base stations 102. 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 120 between the base stations 102 and the UEs 104 may include uplink (UL) (also referred to as reverse link) transmissions from a UE 104 to a base station 102 and/or downlink (DL) (also referred to as forward link) transmissions from a base station 102 to a UE 104. The communication links 120 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 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, WiMedia, Bluetooth, ZigBee, 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 access point (AP) 150 in communication with Wi-Fi stations (STAs) 152 via communication links 154, e.g., in a 5 GHz unlicensed frequency spectrum or the like. When communicating in an unlicensed frequency spectrum, the STAs 152 /AP 150 may perform a clear channel assessment (CCA) prior to communicating in order to determine whether the channel is available.

The small cell 102' may operate in a licensed and/or an unlicensed frequency spectrum. When operating in an unlicensed frequency spectrum, the small cell 102' may employ NR and use the same unlicensed frequency spectrum (e.g., 5 GHz, or the like) as used by the Wi-Fi AP 150. The small cell 102', employing NR in an unlicensed frequency spectrum, may boost coverage to and/or increase capacity of the access network.

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) . The frequencies between FR1 and FR2 are often referred to as mid-band frequencies. 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.

With the above aspects in mind, unless specifically stated otherwise, it should be understood that 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, it should be understood that the term “millimeter wave” or the like if used herein may broadly represent frequencies that may include mid-band frequencies, may be within FR2, or may be within the EHF band.

A base station 102, whether a small cell 102' or a large cell (e.g., macro base station) , may include and/or be referred to as an eNB, gNodeB (gNB) , or another type of base station. Some base stations, such as gNB 180 may operate in a traditional sub 6 GHz spectrum, in millimeter wave frequencies, and/or near millimeter wave frequencies in communication with the UE 104. When the gNB 180 operates in millimeter wave or near millimeter wave frequencies, the gNB 180 may be referred to as a millimeter wave base station. The millimeter wave base station 180 may utilize beamforming 182 with the UE 104 to compensate for the path loss and short range. The base station 180 and the UE 104 may each include a plurality of antennas, such as antenna elements, antenna panels, and/or antenna arrays to facilitate the beamforming.

The base station 180 may transmit a beamformed signal to the UE 104 in one or more transmit directions 182'. The UE 104 may receive the beamformed signal from the base station 180 in one or more receive directions 182” . The UE 104 may also transmit a beamformed signal to the base station 180 in one or more transmit directions. The base station 180 may receive the beamformed signal from the UE 104 in one or more receive directions. The base station 180 /UE 104 may perform beam training to determine the best receive and transmit directions for each of the base station 180 /UE 104. The transmit and receive directions for the base station 180 may or may not be the same. The transmit and receive directions for the UE 104 may or may not be the same.

The EPC 160 may include a Mobility Management Entity (MME) 162, other MMEs 164, a Serving Gateway 166, a Multimedia Broadcast Multicast Service (MBMS) Gateway 168, a Broadcast Multicast Service Center (BM-SC) 170, and a Packet Data Network (PDN) Gateway 172. The MME 162 may be in communication with a Home Subscriber Server (HSS) 174. The MME 162 is the control node that processes the signaling between the UEs 104 and the EPC 160. Generally, the MME 162 provides bearer and connection management. All user Internet protocol (IP) packets are transferred through the Serving Gateway 166, which 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 the BM-SC 170 are connected to the IP Services 176. The IP Services 176 may include the Internet, an intranet, an IP Multimedia Subsystem (IMS) , a PS Streaming Service, and/or other IP services. The BM-SC 170 may provide functions for MBMS user service provisioning and delivery. The BM-SC 170 may serve as an entry point for content provider MBMS transmission, may be used to authorize and initiate MBMS Bearer Services within a public land mobile network (PLMN) , and may be used to schedule MBMS transmissions. The MBMS Gateway 168 may be used to distribute MBMS traffic to the base stations 102 belonging to a 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 an Access and Mobility Management Function (AMF) 192, other AMFs 193, a Session Management Function (SMF) 194, and a User Plane Function (UPF) 195. The AMF 192 may be in communication with a Unified Data Management (UDM) 196. The AMF 192 is the control node that processes the signaling between the UEs 104 and the core network 190. Generally, the AMF 192 provides QoS flow and session management. All user Internet protocol (IP) packets are transferred through the UPF 195. The UPF 195 provides UE IP address allocation as well as other functions. The UPF 195 is connected to the IP Services 197. The IP Services 197 may include the Internet, an intranet, an IP Multimedia Subsystem (IMS) , a Packet Switch (PS) Streaming (PSS) Service, and/or other IP services.

The base station 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) , or some other suitable terminology. The base station 102 provides an access point to the EPC 160 or core network 190 for a UE 104. 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.

Referring again to FIG. 1, in certain aspects, the base station 180 may include a transmission component 199 configured to determine a beam management procedure for the cell, the beam management procedure including at least one of a static beam procedure or a hierarchical beam procedure. Transmission component 199 may also be configured to configure at least one beam table based on the beam management procedure, the at least one beam table corresponding to at least one of the static beam procedure or the hierarchical beam procedure. Transmission component 199 may also be configured to select at least one beam based on a beam identifier (ID) of the at least one beam, the beam ID associated with the at least one beam table. Transmission component 199 may also be configured to configure the at least one selected beam based on the beam ID of the at least one beam. Transmission component 199 may also be configured to send the beam ID of the at least one beam to at least one antenna when the at least one beam is selected. Transmission component 199 may also be configured to transmit the at least one selected beam based on the beam ID associated with the at least one beam table. Transmission component 199 may also be configured to switch or maintain the at least one beam based on the beam ID associated with the at least one beam table. Transmission component 199 may also be configured to receive feedback from at least one user equipment (UE) , where the feedback may correspond to at least one of a UE position, a UE velocity, or an interference measurement.

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.

FIG. 2A is a diagram 200 illustrating an example of a first subframe within a 5G NR frame structure. FIG. 2B is a diagram 230 illustrating an example of DL channels within a 5G NR subframe. FIG. 2C is a diagram 250 illustrating an example of a second subframe within a 5G NR frame structure. FIG. 2D is a diagram 280 illustrating an example of UL channels within a 5G NR subframe. The 5G NR frame structure may be frequency division duplexed (FDD) in which for a particular set of subcarriers (carrier system bandwidth) , subframes within the set of subcarriers are dedicated for either DL or UL, or may be time division duplexed (TDD) in which for a particular set of subcarriers (carrier system bandwidth) , subframes within the set of subcarriers are dedicated for both DL and UL. In the examples provided by FIGs. 2A, 2C, the 5G NR frame structure is assumed to be TDD, with subframe 4 being configured with slot format 28 (with mostly DL) , where D is DL, U is UL, and F is flexible for use between DL/UL, and subframe 3 being configured with slot format 1 (with all UL) . While

subframes

3, 4 are shown with slot formats 1, 28, respectively, any particular subframe may be configured with any of the various available slot formats 0-61. Slot formats 0, 1 are all DL, UL, respectively. Other slot formats 2-61 include a mix of DL, UL, and flexible symbols. UEs are configured with the slot format (dynamically through DL control information (DCI) , or semi-statically/statically through radio resource control (RRC) signaling) through a received slot format indicator (SFI) . Note that the description infra applies also to a 5G NR frame structure that is TDD.

Other wireless communication technologies may have a different frame structure and/or different channels. A frame (10 ms) may be divided into 10 equally sized subframes (1 ms) . Each subframe may include one or more time slots. Subframes may also include mini-slots, which may include 7, 4, or 2 symbols. Each slot may include 7 or 14 symbols, depending on the slot configuration. For slot configuration 0, each slot may include 14 symbols, and for slot configuration 1, each slot may include 7 symbols. The symbols on DL may be cyclic prefix (CP) OFDM (CP-OFDM) symbols. The symbols on UL may be CP-OFDM symbols (for high throughput scenarios) or discrete Fourier transform (DFT) spread OFDM (DFT-s-OFDM) symbols (also referred to as single carrier frequency-division multiple access (SC-FDMA) symbols) (for power limited scenarios; limited to a single stream transmission) . The number of slots within a subframe is based on the slot configuration and the numerology. For slot configuration 0, different numerologies μ0 to 4 allow for 1, 2, 4, 8, and 16 slots, respectively, per subframe. For slot configuration 1, different numerologies 0 to 2 allow for 2, 4, and 8 slots, respectively, per subframe. Accordingly, for slot configuration 0 and numerology μ, there are 14 symbols/slot and 2 ^μ slots/subframe. The subcarrier spacing and symbol length/duration are a function of the numerology. The subcarrier spacing may be equal to 2 ^μ*15 kHz, where μ 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 slot configuration 0 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 FIG. 2B) that are frequency division multiplexed. Each BWP may have a particular numerology.

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

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

As illustrated in FIG. 2C, some of the REs carry DM-RS (indicated as R for one particular configuration, but other DM-RS configurations are possible) for channel estimation at the base station. The UE may transmit DM-RS for the physical uplink control channel (PUCCH) and DM-RS for the physical uplink shared channel (PUSCH) . The PUSCH DM-RS may be transmitted in the first one or two symbols of the PUSCH. The PUCCH DM-RS may be transmitted in different configurations depending on whether short or long PUCCHs are transmitted and depending on the particular PUCCH format used. The UE may transmit sounding reference signals (SRS) . The SRS may be transmitted in the last symbol of a subframe. The SRS may have a comb structure, and a UE may transmit SRS on one of the combs. The SRS may be used by a base station for channel quality estimation to enable frequency-dependent scheduling on the UL.

FIG. 2D illustrates an example of various UL channels within a subframe of a frame. The PUCCH may be located as indicated in one configuration. The PUCCH carries uplink control information (UCI) , such as scheduling requests, a channel quality indicator (CQI) , a precoding matrix indicator (PMI) , a rank indicator (RI) , and hybrid automatic repeat request (HARQ) ACK/NACK feedback. The PUSCH carries data, and may additionally be used to carry a buffer status report (BSR) , a power headroom report (PHR) , and/or UCI.

FIG. 3 is a block diagram of a base station 310 in communication with a UE 350 in an access network. In the DL, IP packets from the EPC 160 may be provided to a controller/processor 375. The controller/processor 375 implements layer 3 and layer 2 functionality. Layer 3 includes a radio resource control (RRC) layer, and layer 2 includes a service data adaptation protocol (SDAP) layer, a packet data convergence protocol (PDCP) layer, a radio link control (RLC) layer, and a medium access control (MAC) layer. The controller/processor 375 provides RRC layer functionality associated with broadcasting of system information (e.g., MIB, SIBs) , RRC connection control (e.g., RRC connection paging, RRC connection establishment, RRC connection modification, and RRC connection release) , inter radio access technology (RAT) mobility, and measurement configuration for UE measurement reporting; PDCP layer functionality associated with header compression /decompression, security (ciphering, deciphering, integrity protection, integrity verification) , and handover support functions; RLC layer functionality associated with the transfer of upper layer packet data units (PDUs) , error correction through ARQ, concatenation, segmentation, and reassembly of RLC service data units (SDUs) , re-segmentation of RLC data PDUs, and reordering of RLC data PDUs; and MAC layer functionality associated with mapping between logical channels and transport channels, multiplexing of MAC SDUs onto transport blocks (TBs) , demultiplexing of MAC SDUs from TBs, scheduling information reporting, error correction through HARQ, priority handling, and logical channel prioritization.

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 318 TX. Each transmitter 318 TX may modulate an RF carrier with a respective spatial stream for transmission.

At the UE 350, each receiver 354 RX receives a signal through its respective antenna 352. Each receiver 354 RX 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 from the EPC 160. 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 from the UE 350. IP packets from the controller/processor 375 may be provided to the EPC 160. 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 316, the RX processor 370, and the controller/processor 375 may be configured to perform aspects in connection with 199 of FIG. 1.

In some aspects of wireless communications, e.g., 5G new radio (NR) communications, cells or base stations may include a smaller size, i.e., small cells or microcells. These small cells may include an increased role in wireless communication networks. Some wireless operators may deploy an increased amount of small cells in order to enhance coverage or capacity on top of larger cell coverage or macrocell coverage. Additionally, some aspects of wireless communications may utilize millimeter wave (mmW) communication, e.g., frequency range two (FR2) , in order to allow small cells to include an expanded communication footprint. For instance, mmW communication may provide increased spectrum resources and/or a reduced air interface latency.

FIG. 4 is a diagram 400 illustrating example beam transmissions. As shown in FIG. 4, diagram 400 includes antenna panel 410 and beams 420-427. Beam 420 includes an azimuth of 0 degrees and an elevation of 90 degrees, beam 421 includes an azimuth of 180 degrees and an elevation of 0 degrees, beam 422 includes an azimuth of 90 degrees and an elevation of 0 degrees, beam 423 includes an azimuth of 45 degrees and an elevation of 0 degrees, beam 424 includes an azimuth of 0 degrees and an elevation of -90 degrees, beam 425 includes an azimuth of 0 degrees and an elevation of 0 degrees, beam 426 includes an azimuth of -45 degrees and an elevation of 0 degrees, and beam 427 includes an azimuth of -90 degrees and an elevation of 0 degrees.

As illustrated in FIG. 4, a number of multiple input multiple output (MIMO) beams, e.g., beams 420-427, may be generated from a mmW small cell antenna panel, e.g., antenna panel 410. Additionally, the antenna panel 410 in FIG. 4 can manage up to a certain number of beams, e.g., 128 beams. Moreover, FIG. 4 depicts that a number of narrow beams, e.g., beams 420-427, may be produced by a mmW small cell antenna panel, e.g., antenna panel 410.

In some aspects of wireless communications, e.g., 5G wireless communications, massive MIMO communication may be an important feature. In one aspect, narrow beams may be utilized to concentrate radio frequency (RF) transmission energy, as well as to provide a high data rate to a UE. In another aspect, narrow beams may increase the risk of UE communication loss, including beam failure and/or radio link failure (RLF) .

Beam management is also an important issue for wireless communications, as well as a challenge for beam scheduling. For instance, beam management may be important for mmW small cells because of a higher spectrum frequency, increased antenna numbers, and/or narrower beam forming, each of which may correspond to a certain frequency, e.g., frequencies below 6 Hz or sub-6 Hz. Additionally, beam management may be important for mmW small cells due to a lower computing capability, which may correspond to a macrocell case. So mmW small cells may benefit from high quality schemes or procedures for beam management.

As indicated herein, the use of mmW small cells may increase the amount of cells and antennae used in wireless communications. This may increase the amount of total beams utilized in wireless communications. Based on the above, it may be beneficial to utilize novel and improved beam management procedures. It may also be beneficial to utilize beam tables for mmW small cells. Further, it may be beneficial to provide novel beam schedulers to manage the beam management procedures and beam tables for mmW small cells.

Aspects of the present disclosure can utilize novel and improved beam management procedures. For instance, aspects of the present disclosure may utilize beam tables for mmW small cells. Additionally, aspects of the present disclosure may utilize novel schedulers and beam schedulers to manage the beam management procedures and beam tables for mmW small cells.

In some aspects, the present disclosure can provide a beam management scheme which comprises multiple parts, e.g., a static beam procedure and a hierarchical beam procedure. In static beam procedures, aspects of the present disclosure can use a predefined beam table for mmW small cells, instead of generating beam characters in runtime. So the present disclosure can utilize a beam table in a static manner. After a 5G service stack up, a scheduler or beam scheduler may select a beam from the static beam table. For each beam in the beam table, the scheduler may determine or understand its elevation and azimuth angle, which can also be according to a number of antenna parameters, e.g., phase, gain, or the like.

FIG. 5 is a diagram 500 illustrating a beam table 510 in accordance with one or more techniques of the present disclosure. FIG. 5 depicts beam table 510 which contains beam identifiers (IDs) for a number of narrow beams, e.g., 128 narrow beams. For example, as shown in FIG. 5, beam table 510 includes beam IDs 5001-5128 corresponding to 128 beams. As illustrated in FIG. 5, beam table 510 includes an elevation span of 120 degrees and an azimuth span of 120 degrees. Each of the beam IDs 5001-5128 in beam table 510 may correspond to a beam with a particular elevation value and azimuth value. For example, beam ID 5010 corresponds to a beam with an elevation of 60 degrees and an azimuth of 15 degrees.

As shown in FIG. 5, beam table 510 corresponds to a static beam procedure, which includes a sample set of a predefined beam array. This beam array can include beams corresponding to a certain elevation range and azimuth range, e.g., a 120 degree elevation range and a 120 degree azimuth range, from a mmW antenna panel. Also, the scheduler may retrieve any one beam according to its beam ID in beam table 510. The scheduler may then send one or more predefined antenna parameters to a RF subsystem.

In some aspects, there may be a flexibility loss during beam transmissions, such that a beam may not be transmitted on a certain elevation or azimuth, e.g., elevation of 60 degrees and an azimuth of 10 degrees. In FIG. 5, this corresponds to the location between

beam IDs

5009 and 5010 in the beam table 510. In some instances, the beam table in FIG. 5 may provide a system simplicity and/or avoid complex antenna parameters computing in runtime.

Aspects of the present disclosure may also include a hierarchical beam structure or hierarchical beam table. In some aspects, a hierarchical beam structure may predefine a number of beam types, e.g., narrow beams, wide beams, and/or ultra-wide beams, in a hierarchical manner. For example, hierarchical beam structures of the present disclosure may include a number of different layers in a beam hierarchy, e.g., one, two, three, or four layers. The amount of layers present in the beam hierarchy or hierarchical beam table may increase or decrease based on different beam implementations.

In some aspects, the lowest layer in the hierarchical beam structure may include the narrowest type of beam, e.g., one or more narrow beams. Also, the highest layer in the hierarchical beam structure may include the broadest type of beam, e.g., one or more ultra-wide beams. For instance, each layer in the hierarchical beam structure that is above another layer may correspond to increasingly broad beams. Alternatively, each layer in the hierarchical beam structure that is above another layer may correspond to increasingly narrow beams. Also, each layer of the hierarchical beam structure may include beams that include a similar elevation and azimuth. Accordingly, the hierarchical beam structure may correspond to multiple layers in a beam table, where each of the layers correspond to one of multiple types of beams, e.g., narrow beams, wide beams, or ultra-wide beams.

FIGs. 6A, 6B, and 6C are diagrams 600, 620, 640, respectively, illustrating an example beam table in accordance with one or more techniques of the present disclosure. The beam table shown in FIGs. 6A-6C may include a number of layers, e.g., three layers. For instance, FIG. 6A displays layer 601 in the beam table, FIG. 6B displays layer 621 in the beam table, and FIG. 6C displays layer 641 in the beam table. Accordingly, FIGs. 6A, 6B, and 6C depict a hierarchical beam structure including one or more layers.

FIG. 6A depicts layer 601 in the beam table which contains beam identifiers (IDs) for a number of beams, e.g., 128 narrow beams. For example, as shown in FIG. 6A, layer 601 in the beam table includes beam IDs 6001-6128 corresponding to 128 beams. As illustrated in FIG. 6A, layer 601 in the beam table includes an elevation span of 120 degrees and an azimuth span of 120 degrees. Each of the beam IDs 6001-6128 in layer 601 may correspond to a beam with a particular elevation value and azimuth value. For example, beam ID 6010 corresponds to a beam with an elevation of 60 degrees and an azimuth of 15 degrees.

FIG. 6B depicts layer 621 in the beam table which contains beam IDs for a number of beams, e.g., 32 wide beams. As shown in FIG. 6B, layer 621 in the beam table includes beam IDs 6201-6232 corresponding to 32 beams. As illustrated in FIG. 6B, layer 621 in the beam table includes an elevation span of 120 degrees and an azimuth span of 120 degrees. Each of the beam IDs 6201-6232 in layer 621 may correspond to a beam with a particular elevation value and azimuth value. In some aspects, a broader beam from a higher layer may have coverage overlap with narrower beams from a lower layer. For example, the coverage of beam ID 6205 in layer 621 may overlap with the coverage of

beam IDs

6009, 6010, 6025, and 6026 in layer 601.

FIG. 6C depicts layer 641 in the beam table which contains beam IDs for a number of beams, e.g., two ultra-wide beams. As shown in FIG. 6C, layer 641 in the beam table includes beam IDs 6401-6402 corresponding to two beams. As illustrated in FIG. 6C, layer 641 in the beam table includes an elevation span of 120 degrees and an azimuth span of 120 degrees. Each of the beam IDs 6401-6402 in layer 641 may correspond to a beam with a particular elevation value and azimuth value. For example, beam ID 6401 may correspond to a beam covering an elevation of 0-120 degrees and an azimuth of 0-60 degrees and beam ID 6402 may correspond to a beam covering an elevation of 0-120 degrees and an azimuth of 60-120 degrees.

FIGs. 6A, 6B, and 6C depict a hierarchical beam structure which can include a number of different layers, e.g., three layers. For example, FIG. 6A illustrates a lower layer in the hierarchical beam structure, which may be 128 narrow beams, similar to FIG. 5 above. FIG. 6B displays a middle or second layer in the hierarchical beam structure, which may include 32 wide beams. So each of the wide beams in FIG. 6B may cover a broader area compared to each of the narrow beams in FIG. 6A. FIG. 6C shows the third or top layer in the hierarchical beam structure, which may include two ultra-wide beams. As such, each of the ultra-wide beams in FIG. 6C may cover a broader area compared to each of the wide beams in FIG. 6B.

As shown in FIGs. 6A-6C, a beam may be selected based on one of the layers in the hierarchical beam structure, e.g., one of the three

layers

601, 621, 641. In some aspects, the beam may be selected by a scheduler or a beam scheduler. The beam hierarchy structure shown in FIGs. 6A-6C may ease or improve the beam selection process of a scheduler, such as a beam selection based on beam adjustment, beam recovery, or the like. The hierarchical beam table in FIGs. 6A-6C may also provide the scheduler with the freedom to select a beam from a convenient layer in the table, such as when adapting to different beam deployment scenarios. In some aspects, the hierarchical beam table may include any number of different layers, e.g., one, two, three, four, or any amount of layers. As shown in FIGs. 6A-6C, these layers in the beam table may correspond to beam IDs for different beam types, e.g., narrow beams, wide beams, or ultra-wide beams.

During the beam selection process, the scheduler may switch or jump between different layers in the beam table to make the beam selection. For instance, during a first selection, the scheduler may select a beam from a lower layer in the beam table, e.g., a narrow beam in layer 601. Also, during a subsequent selection, the scheduler may select a beam from a middle layer in the beam table, e.g., a broad or wide beam in layer 621. Further, during a later selection, the scheduler may select a beam from an upper layer in the beam table, e.g., an ultra-wide beam in layer 641. This beam selection which corresponds to different layers in the beam table may be configurable or adjustable based on different beam deployment scenarios.

As indicated herein, aspects of the present disclosure may include a number of beam hierarchy procedures or principals. In some instances, each layer in the hierarchical beam table may cover a physical space which may be associated with an antenna panel. For instance, each layer in the hierarchical beam table may be viewed from an antenna panel. Also, each higher layer in the beam table hierarchy may cover lower layers in the beam table with some power efficiency loss. Accordingly, beams from higher layers may cover a wider transmission area compared to lower layer beams, but also include a reduced power efficiency than lower layer beams.

In some aspects, the energy of narrower beams may be more concentrated compared to broader or wider beams. For instance, narrower beams may correspond to an improved signal-to-interference plus noise ratio (SINR) compared to broader or wider beams over the same distance. As such, if a UE is stationary and it can handle a narrow beam, then a narrow beam may be utilized as it includes an improved SINR. If the UE is moving fast, then a wider beam may be selected. For example, if a UE is in a car or a train, a narrower beam may result in frequent beam switching, which can result in radio link failure (RLF) . So a wider beam may be selected for fast moving UEs in order to prevent RLF. Also, an ultra-wide beam may be selected for very fast moving UEs.

Additionally, a broader beam may result in a wider and shorter coverage area compared to narrower beams, as well as a lower power efficiency. For instance, the signal strength over a long distance for wider beams may be reduced compared to narrower beams. In some aspects, the scheduler or beam scheduler may determine when to select a narrower beam or a wider beam based on the characteristics of the UE. So the aforementioned layers in the hierarchical beam structure may ease the beam selection process for the scheduler. By utilizing a hierarchical beam structure, a scheduler may be able to adapt to different use cases for UEs.

FIG. 7 is a diagram 700 illustrating example communication between a UE 702 and a cell or base station 704.

At 710, cell 704 may determine a beam management procedure for the cell, the beam management procedure including at least one of a static beam procedure or a hierarchical beam procedure. In some instances, the cell may correspond to a small cell.

At 720, cell 704 may configure at least one beam table based on the beam management procedure, the at least one beam table corresponding to at least one of the static beam procedure or the hierarchical beam procedure. In some aspects, the at least one beam table may correspond to the hierarchical beam procedure, the at least one beam table including one or more layers. Each of the one or more layers may include one or more beam IDs, the one or more beam IDs corresponding to one or more beams types. Also, the one or more beam types may correspond to at least one of one or more narrow beams, one or more wide beams, or one or more ultra-wide beams. In some instances, the at least one beam may be selected based on the one or more layers in the at least one beam table. Further, the at least one beam table may correspond to the static beam procedure, the at least one beam table may include a predefined beam table.

At 730, cell 704 may select at least one beam based on a beam identifier (ID) of the at least one beam, the beam ID associated with the at least one beam table. In some aspects, the beam ID of each of the at least one beam may correspond to at least one of an azimuth parameter or an elevation parameter. Moreover, the at least one beam may be selected by a scheduler or a beam scheduler.

At 740, cell 704 may configure the at least one selected beam based on the beam ID of the at least one beam.

At 750, cell 704 may send the beam ID of the at least one beam to at least one antenna when the at least one beam is selected.

At 760, cell 704 may transmit the at least one selected beam, e.g., beam 764, based on the beam ID associated with the at least one beam table. At 762, UE 702 may receive the at least one beam, e.g., beam 764.

At 770, cell 704 may switch or maintain the at least one beam based on the beam ID associated with the at least one beam table.

At 780, UE 702 may transmit feedback to the cell 704, e.g., feedback 784, where the feedback may correspond to at least one of a UE position, a UE velocity, or an interference measurement. At 782, cell 704 may receive feedback from at least one UE, e.g., feedback 784, where the feedback may correspond to at least one of a UE position, a UE velocity, or an interference measurement. In some aspects, the at least one beam may be selected or switched based on the feedback from the at least one UE and the at least one beam table.

FIG. 8 is a flowchart 800 of a method of wireless communication. The method may be performed by a cell or base station or a component of a cell or base station (e.g., the

base station

102, 180, 310, 704; the apparatus 902; a processing system, which may include the memory 376 and which may be the entire base station or a component of the base station, such as the antenna (s) 320, receiver 318RX, the RX processor 370, the controller/processor 375, and/or the like) . Optional aspects are illustrated with a dashed line. The methods described herein can provide a number of benefits, such as improving communication signaling, resource utilization, and/or power savings.

At 802, the apparatus may determine a beam management procedure for the cell, the beam management procedure including at least one of a static beam procedure or a hierarchical beam procedure, as described in connection with the examples in FIGs. 4, 5, 6A, 6B, 6C, and 7. For example, 802 may be performed by determination component 940. In some instances, the cell may correspond to a small cell, as described in connection with the examples in FIGs. 4, 5, 6A, 6B, 6C, and 7.

At 804, the apparatus may configure at least one beam table based on the beam management procedure, the at least one beam table corresponding to at least one of the static beam procedure or the hierarchical beam procedure, as described in connection with the examples in FIGs. 4, 5, 6A, 6B, 6C, and 7. For example, 804 may be performed by determination component 940.

In some aspects, the at least one beam table may correspond to the hierarchical beam procedure, the at least one beam table including one or more layers, as described in connection with the examples in FIGs. 4, 5, 6A, 6B, 6C, and 7. Each of the one or more layers may include one or more beam IDs, the one or more beam IDs corresponding to one or more beams types, as described in connection with the examples in FIGs. 4, 5, 6A, 6B, 6C, and 7. Also, the one or more beam types may correspond to at least one of one or more narrow beams, one or more wide beams, or one or more ultra-wide beams, as described in connection with the examples in FIGs. 4, 5, 6A, 6B, 6C, and 7. In some instances, the at least one beam may be selected based on the one or more layers in the at least one beam table, as described in connection with the examples in FIGs. 4, 5, 6A, 6B, 6C, and 7. Further, the at least one beam table may correspond to the static beam procedure, the at least one beam table may include a predefined beam table, as described in connection with the examples in FIGs. 4, 5, 6A, 6B, 6C, and 7.

At 806, the apparatus may select at least one beam based on a beam identifier (ID) of the at least one beam, the beam ID associated with the at least one beam table, as described in connection with the examples in FIGs. 4, 5, 6A, 6B, 6C, and 7. For example, 806 may be performed by determination component 940. In some aspects, the beam ID of each of the at least one beam may correspond to at least one of an azimuth parameter or an elevation parameter, as described in connection with the examples in FIGs. 4, 5, 6A, 6B, 6C, and 7. Moreover, the at least one beam may be selected by a scheduler or a beam scheduler, as described in connection with the examples in FIGs. 4, 5, 6A, 6B, 6C, and 7.

At 808, the apparatus may configure the at least one selected beam based on the beam ID of the at least one beam, as described in connection with the examples in FIGs. 4, 5, 6A, 6B, 6C, and 7. For example, 808 may be performed by determination component 940.

At 810, the apparatus may send the beam ID of the at least one beam to at least one antenna when the at least one beam is selected, as described in connection with the examples in FIGs. 4, 5, 6A, 6B, 6C, and 7. For example, 810 may be performed by determination component 940.

At 812, the apparatus may transmit the at least one selected beam based on the beam ID associated with the at least one beam table, as described in connection with the examples in FIGs. 4, 5, 6A, 6B, 6C, and 7. For example, 812 may be performed by determination component 940.

At 814, the apparatus may switch or maintain the at least one beam based on the beam ID associated with the at least one beam table, as described in connection with the examples in FIGs. 4, 5, 6A, 6B, 6C, and 7. For example, 814 may be performed by determination component 940.

At 816, the apparatus may receive feedback from at least one UE, where the feedback may correspond to at least one of a UE position, a UE velocity, or an interference measurement, as described in connection with the examples in FIGs. 4, 5, 6A, 6B, 6C, and 7. For example, 816 may be performed by determination component 940. In some aspects, the at least one beam may be selected or switched based on the feedback from the at least one UE and the at least one beam table, as described in connection with the examples in FIGs. 4, 5, 6A, 6B, 6C, and 7.

FIG. 9 is a diagram 900 illustrating an example of a hardware implementation for an apparatus 902. The apparatus 902 is a cell or a base station and includes a baseband unit 904. The baseband unit 904 may communicate through a cellular RF transceiver with the UE 104. The baseband unit 904 may include a computer-readable medium /memory. The baseband unit 904 is responsible for general processing, including the execution of software stored on the computer-readable medium /memory. The software, when executed by the baseband unit 904, causes the baseband unit 904 to perform the various functions described supra. The computer-readable medium /memory may also be used for storing data that is manipulated by the baseband unit 904 when executing software. The baseband unit 904 further includes a reception component 930, a communication manager 932, and a transmission component 934. The communication manager 932 includes the one or more illustrated components. The components within the communication manager 932 may be stored in the computer-readable medium /memory and/or configured as hardware within the baseband unit 904. The baseband unit 904 may be a component of the BS 310 and may include the memory 376 and/or at least one of the TX processor 316, the RX processor 370, and the controller/processor 375.

The communication manager 932 includes a determination component 940 that is configured to determine a beam management procedure for the cell, the beam management procedure including at least one of a static beam procedure or a hierarchical beam procedure, e.g., as described in connection with step 802 above. Determination component 940 can also be configured to configure at least one beam table based on the beam management procedure, the at least one beam table corresponding to at least one of the static beam procedure or the hierarchical beam procedure, e.g., as described in connection with step 804 above. Determination component 940 can also be configured to select at least one beam based on a beam identifier (ID) of the at least one beam, the beam ID associated with the at least one beam table, e.g., as described in connection with step 806 above. Determination component 940 can also be configured to transmit the at least one selected beam based on the beam ID associated with the at least one beam table, e.g., as described in connection with step 812 above.

The apparatus may include additional components that perform each of the blocks of the algorithm in the aforementioned flowcharts of FIGs. 7 and 8. As such, each block in the aforementioned flowcharts of FIGs. 7 and 8 may be performed by a component and the apparatus may include one or more of those components. The components may be one or more hardware components specifically configured to carry out the stated processes/algorithm, implemented by a processor configured to perform the stated processes/algorithm, stored within a computer-readable medium for implementation by a processor, or some combination thereof.

In one configuration, the apparatus 902, and in particular the baseband unit 904, includes means for determining a beam management procedure for the cell, the beam management procedure including at least one of a static beam procedure or a hierarchical beam procedure. The apparatus 902 can also include means for configuring at least one beam table based on the beam management procedure, the at least one beam table corresponding to at least one of the static beam procedure or the hierarchical beam procedure. The apparatus 902 can also include means for selecting at least one beam based on a beam identifier (ID) of the at least one beam, the beam ID associated with the at least one beam table. The apparatus 902 can also include means for transmitting the at least one selected beam based on the beam ID associated with the at least one beam table. The aforementioned means may be one or more of the aforementioned components of the apparatus 902 configured to perform the functions recited by the aforementioned means. As described supra, the apparatus 902 may include the TX Processor 316, the RX Processor 370, and the controller/processor 375. As such, in one configuration, the aforementioned means may be the TX Processor 316, the RX Processor 370, and the controller/processor 375 configured to perform the functions recited by the aforementioned means.

Further disclosure is included in the Appendix.

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 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 is 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” 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. 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. Moreover, 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, ” 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. ”

Appendix

Hierarchy Beam Table design for mmW small cell

PROBLEM DESCRIPTION:

With 5G roll out, small cell is playing more and more important role in network. Operators need to deploy many small cells, to enhance capacity on to p of Macrocell coverage. We can predict Millimeter Wave (in 3GPP standard, so called FR2, in below text we will use abbreviation “mmW” ) small cell will expand its footprint worldwide since now, because mmW can provide much more spectrum resource and much shorter air interface latency. For 5G, massive MIMO is a key feature. Below Picture-1 depict MIMO beams generate from a mmW small cell antenna panel. On one aspect, we need narrow beams to concentrate RF transmission energy, then provide high data rate to UE. On another aspect, narrow beams increase risk of UE lost, incl. beam failure and radio link failure. Beam management is a new issue for 5G, also a big challenge for scheduler. The situation is more severe for mmW small cell because of higher spectrum frequency, higher antenna numbers, narrower beam forming (these three compare with Sub6Hz case) and lower computing capability (this one compares with Macrocell case) . So, mmW small cell need good schema for beam management.

Picture-1 to depict sample narrow beams produced by mmW small cell antenna panel:

INVENTION DESCRIPTION:

The invention provides a beam management schema which compose two key parts: static and hierarchy.

Static means we use predefined beam table for mmW small cell, instead of generating beam characters in runtime. After 5G service stack up, scheduler will only choose beam from this static table, for every beam in this table, scheduler know its elevation and azimuth angle, also according antenna parameters (e.g. phase, gain, etc) . Below Picture-2 depict (part of) a sample beam table which contains 128 narrow beams. As a total, these beams cover 120 degree elevation and 120 degree azimuth, from mmW antenna panel. Scheduler can retrieve any one by its beam ID and send predefined antenna parameters to RF subsystem. There is flexibility loss, e.g. we cannot transmit a beam with elevation 60 and azimuth 10 (which in space present between

beam

9 and 10 of below sample table) . While, we get system simplicity and avoid complex antenna parameters computing in runtime.

Picture-2 to depict a sample set of predefined beams array which contains 128 narrow beams:

Hierarchy means we predefine not only narrow beams, but also wide beams on a hierarchy manner. How many layers present in hierarchy is just an implementation detail. Below Picture-3 depict a 3-layer design. The lowest layer is 128 narrow beams as above, the 2 ^nd layer is 32 wide beams, the 3 ^rd layer is 2 ultra-wide beams. This kind of hierarchy structure will make scheduler’s work easy, especially for beam adjustment, beam recovery, etc. This kind of hierarchy beam table also give scheduler freedom on choosing most convenient layer when adapter to deployment scenarios. In this invention, we need not put too much restriction on hierarchy layer design aspect. We only need to keep two principals: first, every layer needs to cover whole physical space which can be seen from antenna panel; second, every higher layer should cover lower layers, of course, with some power efficiency loss.

Picture-3 to depict a sample 3-layer hierarchy beam design:

DETECTABILITY:

It is a bit complicate to identify if a mmW small cell uses our invention or not. We need to use an engineering UE to test below steps.

1. Choose a typical deployment case, e.g. a mmW small cell a bit far away from other Macrocell and small cells. To assure, in our whole testing period, UE only attach to this small cell.

2. Walk UE around this mmW small cell. Record walk track which should be a rough circle with timestamp mark. Repeat this walk for several rounds. Analyze log to see if TCI state only change in fix step size, e.g. TCI state change every 15 degree. This pattern can prove our invention is used, at least for “static” part.

3. Continue walk UE around this mmW small cell, but much faster, e.g. by driving a car to trigger UE lost happen. A well-designed scheduler may detect this kind of failure and change to higher layer beams. Again, analyze log to see if TCI state change step size enlarged, e.g. from 15 degree to 30 degree. This pattern can prove our invention is used, for “hierarchy” part.

Claims

A method of wireless communication of a cell, comprising:

determining a beam management procedure for the cell, the beam management procedure including at least one of a static beam procedure or a hierarchical beam procedure;

configuring at least one beam table based on the beam management procedure, the at least one beam table corresponding to at least one of the static beam procedure or the hierarchical beam procedure;

selecting at least one beam based on a beam identifier (ID) of the at least one beam, the beam ID associated with the at least one beam table; and

transmitting the at least one selected beam based on the beam ID associated with the at least one beam table.
The method of claim 1, wherein the at least one beam table corresponds to the hierarchical beam procedure, the at least one beam table including one or more layers.
The method of claim 2, wherein each of the one or more layers includes one or more beam IDs, the one or more beam IDs corresponding to one or more beams types.
The method of claim 3, wherein the one or more beam types correspond to at least one of one or more narrow beams, one or more wide beams, or one or more ultra-wide beams.
The method of claim 2, wherein the at least one beam is selected based on the one or more layers in the at least one beam table.
The method of claim 1, wherein the at least one beam table corresponds to the static beam procedure, the at least one beam table including a predefined beam table.
The method of claim 1, further comprising:

configuring the at least one selected beam based on the beam ID of the at least one beam.
The method of claim 1, further comprising:

sending the beam ID of the at least one beam to at least one antenna when the at least one beam is selected.
The method of claim 1, further comprising:

switching or maintaining the at least one beam based on the beam ID associated with the at least one beam table.
The method of claim 1, wherein the beam ID of each of the at least one beam corresponds to at least one of an azimuth parameter or an elevation parameter.
The method of claim 1, wherein the at least one beam is selected by a scheduler or a beam scheduler.
The method of claim 1, wherein the cell corresponds to a small cell.
The method of claim 1, further comprising:

receiving feedback from at least one user equipment (UE) , wherein the feedback corresponds to at least one of a UE position, a UE velocity, or an interference measurement.
The method of claim 13, wherein the at least one beam is selected or switched based on the feedback from the at least one UE and the at least one beam table.
An apparatus for wireless communication of a cell, comprising:

a memory; and

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

determine a beam management procedure for the cell, the beam management procedure including at least one of a static beam procedure or a hierarchical beam procedure;

configure at least one beam table based on the beam management procedure, the at least one beam table corresponding to at least one of the static beam procedure or the hierarchical beam procedure;

select at least one beam based on a beam identifier (ID) of the at least one beam, the beam ID associated with the at least one beam table; and

transmit the at least one selected beam based on the beam ID associated with the at least one beam table.
The apparatus of claim 15, wherein the at least one beam table corresponds to the hierarchical beam procedure, the at least one beam table including one or more layers.
The apparatus of claim 16, wherein each of the one or more layers includes one or more beam IDs, the one or more beam IDs corresponding to one or more beams types.
The apparatus of claim 17, wherein the one or more beam types correspond to at least one of one or more narrow beams, one or more wide beams, or one or more ultra-wide beams.
The apparatus of claim 16, wherein the at least one beam is selected based on the one or more layers in the at least one beam table.
The apparatus of claim 15, wherein the at least one beam table corresponds to the static beam procedure, the at least one beam table including a predefined beam table.
The apparatus of claim 15, wherein the at least one processor is further configured to:

configure the at least one selected beam based on the beam ID of the at least one beam.
The apparatus of claim 15, wherein the at least one processor is further configured to:

send the beam ID of the at least one beam to at least one antenna when the at least one beam is selected.
The apparatus of claim 15, wherein the at least one processor is further configured to:

switch or maintain the at least one beam based on the beam ID associated with the at least one beam table.
The apparatus of claim 15, wherein the beam ID of each of the at least one beam corresponds to at least one of an azimuth parameter or an elevation parameter.
The apparatus of claim 15, wherein the at least one beam is selected by a scheduler or a beam scheduler.
The apparatus of claim 15, wherein the cell corresponds to a small cell.
The apparatus of claim 15, wherein the at least one processor is further configured to:

receive feedback from at least one user equipment (UE) , wherein the feedback corresponds to at least one of a UE position, a UE velocity, or an interference measurement.
The apparatus of claim 27, wherein the at least one beam is selected or switched based on the feedback from the at least one UE and the at least one beam table.
An apparatus for wireless communication of a cell, comprising:

means for determining a beam management procedure for the cell, the beam management procedure including at least one of a static beam procedure or a hierarchical beam procedure;

means for configuring at least one beam table based on the beam management procedure, the at least one beam table corresponding to at least one of the static beam procedure or the hierarchical beam procedure;

means for selecting at least one beam based on a beam identifier (ID) of the at least one beam, the beam ID associated with the at least one beam table; and

means for transmitting the at least one selected beam based on the beam ID associated with the at least one beam table.
The apparatus of claim 29, wherein the at least one beam table corresponds to the hierarchical beam procedure, the at least one beam table including one or more layers.
The apparatus of claim 30, wherein each of the one or more layers includes one or more beam IDs, the one or more beam IDs corresponding to one or more beams types.
The apparatus of claim 31, wherein the one or more beam types correspond to at least one of one or more narrow beams, one or more wide beams, or one or more ultra-wide beams.
The apparatus of claim 30, wherein the at least one beam is selected based on the one or more layers in the at least one beam table.
The apparatus of claim 29, wherein the at least one beam table corresponds to the static beam procedure, the at least one beam table including a predefined beam table.
The apparatus of claim 29, further comprising:

means for configuring the at least one selected beam based on the beam ID of the at least one beam.
The apparatus of claim 29, further comprising:

means for sending the beam ID of the at least one beam to at least one antenna when the at least one beam is selected.
The apparatus of claim 29, further comprising:

means for switching or maintaining the at least one beam based on the beam ID associated with the at least one beam table.
The apparatus of claim 29, wherein the beam ID of each of the at least one beam corresponds to at least one of an azimuth parameter or an elevation parameter.
The apparatus of claim 29, wherein the at least one beam is selected by a scheduler or a beam scheduler.
The apparatus of claim 29, wherein the cell corresponds to a small cell.
The apparatus of claim 29, further comprising:

means for receiving feedback from at least one user equipment (UE) , wherein the feedback corresponds to at least one of a UE position, a UE velocity, or an interference measurement.
The apparatus of claim 41, wherein the at least one beam is selected or switched based on the feedback from the at least one UE and the at least one beam table.
A computer-readable medium storing computer executable code for wireless communication of a cell, the code when executed by a processor causes the processor to:

determine a beam management procedure for the cell, the beam management procedure including at least one of a static beam procedure or a hierarchical beam procedure;

configure at least one beam table based on the beam management procedure, the at least one beam table corresponding to at least one of the static beam procedure or the hierarchical beam procedure;

select at least one beam based on a beam identifier (ID) of the at least one beam, the beam ID associated with the at least one beam table; and

transmit the at least one selected beam based on the beam ID associated with the at least one beam table.