WO2021232231A1

WO2021232231A1 - Apparatus and method to induce high-sensitive channel state information reference signal beam switching

Info

Publication number: WO2021232231A1
Application number: PCT/CN2020/091020
Authority: WO
Inventors: Zhuoqi XU; Yuankun ZHU; Pan JIANG
Original assignee: Qualcomm Incorporated
Priority date: 2020-05-19
Filing date: 2020-05-19
Publication date: 2021-11-25

Abstract

A user equipment (UE) performs beam measurements for a plurality of beams. The UE determines that a candidate beam among the plurality of beams is better than a current serving beam of the UE. The UE modifies at least one beam measurement for one or more of the candidate beam and the current serving beam. The UE reports the at least one modified beam measurement to a base station.

Description

APPARATUS AND METHOD TO INDUCE HIGH-SENSITIVE CHANNEL STATE INFORMATION REFERENCE SIGNAL BEAM SWITCHING

BACKGROUND Technical Field

The present disclosure relates generally to communication systems, and more particularly, to a wireless communication involving a beam switching.

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 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 for wireless communication at a user equipment (UE) . The apparatus performs beam measurements for a plurality of beams. The apparatus determines that a candidate beam among the plurality of beams is better than a current serving beam of the apparatus. The apparatus modifies at least one beam measurement for one or more of the candidate beam and the current serving beam. The apparatus reports the at least one modified beam measurement to a base station.

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.

FIGs. 2A, 2B, 2C, and 2D are diagrams illustrating examples of a first 5G/NR frame, DL channels within a 5G/NR subframe, a second 5G/NR frame, and UL channels within a 5G/NR subframe, respectively.

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 of a wireless communications system.

FIG. 5 illustrates an example communication flow between a UE and a base station.

FIG. 6 is a flowchart of a method of wireless communication.

FIG. 7 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.

Aspects presented herein may assist a UE to prompt a serving base station to initiate a beam switching command for one or more beams by modifying at least one parameter of the beam measurement reported to the serving base station. Thus, aspects presented herein may enable the UE to facilitate a beam switching from the base station by enlarging the signal quality gap between a current serving beam and a candidate beam, such that the base station is more likely to request the UE to switch from the current beam to the candidate beam.

FIG. 1 is a diagram illustrating an example of a wireless communications system and an access network 100. In certain aspects, the UE 104 may include a beam measurement modification component 198 configured to modify one or more parameters of a beam measurement (e.g., RSRP, RI, PMI and/or CQI) to enlarge the channel quality gap between a current serving beam and a candidate beam, thereby prompting the base station 102 to command the UE 104 to switch from the current serving beam to the candidate beam.

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 in a 5 GHz unlicensed frequency spectrum. 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 5 GHz unlicensed frequency spectrum 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.

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 (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 an mmW base station. Extremely high frequency (EHF) is part of the RF in the electromagnetic spectrum. EHF has a range of 30 GHz to 300 GHz and a wavelength between 1 millimeter and 10 millimeters. Radio waves in the band may be referred to as a millimeter wave. Near mmW may extend down to a frequency of 3 GHz with a wavelength of 100 millimeters. The super high frequency (SHF) band extends between 3 GHz and 30 GHz, also referred to as centimeter wave. Frequency range bands include frequency range 1 (FR1) , which includes frequency bands below 7.225 GHz, and frequency range 2 (FR2) , which includes frequency bands above 24.250 GHz. Communications using the mmW /near mmW radio frequency (RF) band (e.g., 3 GHz–300 GHz) has extremely high path loss and a short range. Base stations /UEs may operate within one or more frequency range bands. The mmW base station 180 may utilize beamforming 182 with the UE 104 to compensate for the extremely high 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 a 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.

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 34 (with mostly UL) . While

subframes

3, 4 are shown with slot formats 34, 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 _x for one particular configuration, where 100x is the port number, 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) , each CCE including nine RE groups (REGs) , each REG including four consecutive REs in an OFDM symbol. A PDCCH within one BWP may be referred to as a control resource set (CORESET) . 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 318TX. Each transmitter 318TX may modulate an RF carrier with a respective spatial stream for transmission.

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

The controller/processor 359 can be associated with a memory 360 that stores program codes and data. The memory 360 may be referred to as a computer-readable medium. In the UL, the controller/processor 359 provides demultiplexing between transport and logical channels, packet reassembly, deciphering, header decompression, and control signal processing to recover IP packets 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 368, the RX processor 356, and the controller/processor 359 may be configured to perform aspects in connection with 198 of FIG. 1.

In a communication involving beamforming at high frequencies, such as at FR2, due to the high directivity of CSI-RS beam and path loss of mmW frequencies, maintaining the condition of the beam pair link (s) (BPL) between a base station and a UE may be important. FIG. 4 is a diagram 400 of a wireless communications system. The base station 402 may correspond to the

base station

310, 102, 180, and/or another base station. For example, the base station 402 may be a mmW base station. The UE 404 may correspond to the

UE

350, 104, etc. The base station 402 may communicate with the UE 404 using an active beam. During a communication, the active beam (e.g., one of 420a-e) of the base station 402 may be paired with a first beam (e.g., one of 416a-d) at the UE 404 to form an active BPL 406. The UE 404 may identify beam pairs for communication (e.g., uplink and/or downlink communication) with the base station 402.

When the UE 404 is connecting to the base station 402 (e.g., via initial access) or is in a connected state (e.g., RRC connected) with the base station 402, a beam management procedure may be used by the base station 402 and the UE 404 to configure their RX and/or TX beams for the downlink and/or uplink transmissions. For example, during beam management procedure, the base station 402 may transmit one or more CSI-RS 408 over one or more beams (e.g., BPL 406,

beams

420a, 420b, 420c, 420d, 420e, etc. ) , where the one or more CSI-RS 408 may be transmitted periodically or aperiodically. After receiving the CSI-RS 408 from the base station 402 (e.g., via BPL 406,

beams

416a, 416b, 416c, 416d, etc. ) , the UE 404 may perform a beam measurement for the one or more beams, such as by computing the reference signal receive power (RSRP) , rank indicator (RI) , precoding matrix indication (PMI) , and/or channel quality indicator (CQI) based at least in part on the one or more CSI-RS 408, and report the CSI-RS beam measurement 410 (e.g., via CSF report with CRI-RSRP, CRI-RI-PMI-CQI) for the one or more beams back to the base station 402. To optimize the network transmission and/or to achieve stable higher data rate, the beam management procedure may configure the UE 404 to stay at the best CSI-RS beam (s) of the base station 402. Thus, after the base station 402 receives the CSI-RS beam measurement 410 from the UE 404, the base station 402 may have the UE 404 stay on the current beam (s) , or may request that the UE 404 switches one or more beam (e.g., BPL) to another beam (s) with better beam measurements. In general, the base station 402 may request for the UE 404 to switch beam (s) when there are candidate beams having better beam measurements than the UE’s current serving beam. In some examples, the base station may indicate for the UE to switch beams when the candidate beam is better than the current serving beam by at least a defined offset amount.

However, beam switching based on the CSI-RS measurement may not be triggered by the UE 404 (e.g., when the offset is not met) . The beam switching triggering procedure may be controlled by the base station 402 and the UE 404 may not have the capability or authority to request or initiate the beam switching or to unilaterally apply a beam switch. For example, after the UE 404 transmits the CSI-RS beam measurement 410 to base station 402, the UE 404 may then wait for a beam switching command from the base station 402 in order to apply a beam switch. Whether a CSI-RS beam switching is to be triggered may be based on the strategy and/or configuration at the network side (e.g., base station 402) . For example, the UE 404 may not know the core decision algorithm regarding the beam switching employed by the base station 402. If the base station 402 determines not to initiate the beam switching, the UE 404 may not be able to switch beams even if there are better beams for transmission. It may also be possible that a current CSI-RS beam suddenly drops in quality (e.g., due to a blockage) , and the UE 404 may fail to get the CSI-RS beam switching command from the base station 402, which may result in a radio link failure occurring in the current serving CSI-RS beam.

Aspects presented herein may assist a UE to prompt or motivate the serving base station to initiate a beam switching command for one or more beams by modifying at least one parameter of the UE’s beam measurement for the base station (e.g., CSI-RS beam measurement 410) . Thus, aspects presented herein may enable the UE to facilitate or indirectly request a beam switching from the base station when certain pre-defined criteria or triggering condition occurs at the UE. For example, when a UE is configured to report CSI-RS beam measurements (e.g., RSRP, RI, PMI and/or CQI, etc. ) to a base station periodically or aperiodically for beams switching judgement, the UE may adjust the value for at least one of the beam measurements to enlarging the gap (e.g., offset) of the beam quality measured between a candidate beam and a current serving beam. As the base station observes a larger gap in the beam (e.g., signal) quality between the candidate beam and the serving beam, the base station is more likely to trigger a beam switching for the UE, e.g., requesting the UE to switch from the current serving beam to the candidate beam. The UE may initiate or trigger the measurement adjustment based on the channel condition, the base station’s response to the CSI-RS beam measurement, and/or when certain condition or criteria is met at the UE.

In one example, when the CQI of the UE’s current serving CSI-RS beam (e.g., 402a or BPL 406) is lower than a threshold value (e.g., THRESHOLD_CQI) , the UE may reduce the CQI to be reported to the base station, such as by subtracting the CQI with a pre-defined value. Thus, the base station may observe a larger gap in the beam quality between the current serving beam and a potential candidate beam, and the base station may then trigger the beam switching for the UE. In another example, if a candidate CSI-RS beam has an RSRP better than the current serving CSI-RS beam, e.g., by at least an offset amount, the UE may give a further plus to the RSRP of the candidate beam when reporting the RSRP to the base station, such as by adding a pre-defined value or variable to the RSRP. Thus, the base station may be more likely to initiate the beam switching to the candidate beam, in response to the adjusted RSRP, because the base station observes a larger offset in the quality of beam measurement between the current serving beam and the candidate beam. In yet another example, when both the CQI of the serving CSI-RS beam is lower than a threshold and the RSRP of the candidate CSI-RS beam is better than the serving CSI-RS beam by at least an offset amount, the UE may reduce the reported CQI to enhance or highlight of the situation of the serving CSI-RS beam that is represented to the base station, and/or the UE may increase the reported RSRP of the candidate CSI-RS beam (e.g., to increase the likelihood of the candidate CSI-RS beam being selected by the base station for beam switching) . By enlarging the signal quality gap between the current serving beam and the candidate beam, the UE may indirectly request for the base station to command the beam switching based on the UE’s preference.

Table 1 below illustrates an example of condition or criteria that may be defined or configured at a UE for triggering the beam measurement adjustment for reporting.

Table 1

The specific numbers provided in Table 1 are merely an example to illustrate the concept. The aspects presented herein may be applied for various threshold values, offset values, reduction values, and compensation values, and are not limited to the specific examples in Table 1

Based on the condition or criteria in the example in Table 1, when the CQI of the current beam is below a 10 CQI index, and there is a candidate beam that has an RSRP that is higher than the current serving beam by at least 2 dB offset, the UE may subtract 2 from the CQI when reporting the CQI of the current beam and increase the RSRP by 2 dB when reporting the RSRP of the candidate beam to the base station. For example, if the CQI of the current serving beam has a CQI index of 8 and a candidate beam has an RSRP of 11 dB, the CQI of the current serving beam is below the threshold and the RSRP of the candidate beam exceeds the current serving beam by the offset. Therefore, the UE may trigger the beam measurement adjustment for the CQI of the current beam to 6 CQI index (e.g., minus the adjustment value of 2) and for the RSRP of the candidate beam to 13 dB (e.g., plus the value of 2) . Then, the UE may report the adjusted measurement values to the base station. Thus, the base station may observe a larger offset between the candidate beam and the current serving beam (e.g., the offset may be 7 dB instead of 3 dB) , and the base station may be more likely to initiate the beam switching. On the other hand, if the condition is not met, then the UE may not apply the beam measurement adjustment. For example, if the CQI of the current serving beam has an 11 CQI index (e.g., above the threshold) or if the RSRP of the candidate beam is 1 dB higher than the current serving beam (e.g., below the offset) , then the UE may not adjust the beam measurements when reporting the beam measurements to the base station, where the beam measurements are reported as measured.

While the examples above use CQI of the current serving beam and RSRP of the candidate beam for illustration, aspects described herein may also apply to other types of beam-related measurements, such as the RI, PMI, etc. The parameters such as the threshold, offset, minus and plus illustrate in Table 1 may be configured to condition (s) suitable for the UE and the particular measurement. For example, any measurement adjustment that enlarges the quality gap between a current serving CSI-RS beam and a candidate CSI-RS beam to facilitate the handover command from the base station may fall within the scope of the present disclosure. In addition, there may be one or more conditions for triggering the beam measure adjustment. For example, in one example, the beam measure adjustment may be triggered when the CQI of the current serving beam is below a threshold. In another example, the beam measure adjustment may be triggered when the RSRP of a candidate beam is higher than the current serving beam by a threshold. In another example, the beam measure adjustment may be triggered when both the CQI of the current serving beam is below a threshold and the RSRP of a candidate beam is higher than the current serving beam by a threshold. In another example, the beam measure adjustment may be triggered when the CQI of the current serving beam is below a threshold and the RSRP of a candidate beam is above a threshold, etc.

FIG. 5 illustrates an example communication flow 500 between a UE 504 and a base station 502. The base station 502 may be an aspect of the

base station

402, 310, 102, the mmW base station 180, and/or another base station. The UE 504 may be an aspect of the

UE

404, 350, 104, 182, and/or another UE. At 506, the UE 504 may be connected (e.g., in an RRC connected state) to the base station 502. During the connected state at 506, the base station 502 may configure the UE 504 to detect and measure one or more beams periodically or aperiodically. For example, the base station 502 may configure parameters such as reportQuantity cri-RSRP and/or cri-RI-PMI-CQI to the UE 504, and the report type may be periodic. This implies that the UE 504 may report the RSRP, RI, PMI and/or CQI for one or more current serving beam and/or candidate beam.

At 508, based on the reporting configuration from the base station 502, the UE 504 may perform CSI-RS beam detection and measurements for one or more CSI-RS beams. The measurement may include measuring the beam quality for both the current serving beam (s) and the candidate beam (s) .

At 510, the UE 504 may determine whether the CQI of the current serving beam is lower than a threshold. If the CQI of the current serving beam is below a threshold, such as described in connection with Table 1, the UE 504 may proceed to step 512. If the CQI of the current serving beam is not below the threshold, then the UE 504 may continue to perform the CSI-RS beam detection and measurements at 508, and report the measured CQI of the current serving beam to the base station 502 at 511.

At 512, after determining that the CQI of the current serving beam is below the threshold, if the RSRP of a candidate CSI-RS beam is higher than the current serving beam by an offset, the UE 504 may proceed with adjusting the beam measurements, such as described in connection with Table 1. If the RSRP of the candidate CSI-RS beam does not exceed the current serving beam by the offset, then the UE 504 may continue to perform the CSI-RS beam detection and measurements at 508, and report the measured RSRP of the candidate CSI-RS beam to the base station 502 at 513.

At 514, after determining that beam measurement adjustment may apply, the UE 504 may reduce the CQI of the current serving beam by a value, and/or add a value to the RSRP of the candidate beam, such as described in connection with Table 1. The UE 504 may then report the adjusted beam measurement value (s) to the base station 502, such as via a channel state feedback (CSF) at 516.

In response to the CSF from the UE 504, the base station 502 may initiate a beam switching command by sending a handover request 518 to the UE 504. For example, the base station 502 may initiate the beam switching when it determines that the beam quality between the current serving beam and the candidate serving beam exceeds a value or offset defined by the core decision algorithm of the base station 502. In response to the handover request 518, the UE 504 may transmit a beam switch confirmation (e.g., handover complete confirmation 520) to the base station 502 confirming that the UE 504 has switched the beam as requested (e.g., from the current serving beam to the candidate beam) .

FIG. 6 is a flowchart of a method 600 of wireless communication. The method may be performed by a UE or a component of a UE (e.g., the

UE

104, 350, 404; a processing system, which may include the memory 360 and which may be the entire UE 350 or a component of the UE 350, such as the TX processor 368, the RX processor 356, and/or the controller/processor 359) . Optional aspects are illustrated with a dashed line. The method may enable the UE to adjust one or more beam measurement parameter to enlarge the difference of the beam quality between a current serving beam and a candidate beam, thereby facilitating the base station to initiate beam switching.

At 602, the UE may perform beam measurements for a plurality of beams, such as described in connection with FIGs. 4 and 5. The beam measurements may include measurement of at least one of RSRP, CQI, PMI, CRI and RI of the plurality of beams, such as described in connection with, such as described in connection with Table 1 and FIGs. 4 and 5.

At 604, the UE may determine that a candidate beam among the plurality of beams is better than a current serving beam of the UE, such as described in connection with Table 1 and FIGs. 4 and 5. The plurality of beams may comprise both the candidate beam and the current serving beam. In one example, the UE may determine that the candidate beam is better than the current serving beam if the current serving beam’s beam measurement is below a threshold, such as described in connection with Table 1 and FIG. 5. In another example, the UE may determine that the candidate beam is better than the current serving beam if the current serving beam’s beam measurement is below a threshold and the candidate beam’s beam measurement is better than the current serving beam by an offset, such as described in connection with Table 1 and FIG. 5.

At 606, the UE may modify at least one beam measurement for one or more of the candidate beam and the current serving beam, such as described in connection with Table 1 and FIGs. 4 and 5. In one example, modifying the at least one beam measurement for one or more of the candidate beam and the current serving beam may include increasing a value of a measurement for the candidate beam, such as described in connection with Table 1 and FIG. 5. In other example, modifying the at least one beam measurement for one or more of the candidate beam and the current serving beam may include decreasing a value of a beam measurement for the serving beam, such as described in connection with Table 1 and FIG. 5. In yet another example, modifying the at least one beam measurement for one or more of the candidate beam and the current serving beam may include increasing a candidate beam measurement and decreasing a serving beam measurement, such as described in connection with Table 1 and FIG. 5.

At 608, after modifying at least one beam measurement for one or more of the candidate beam and the current serving beam, the UE may report the at least one modified beam measurement to the base station, such as described in connection with Table 1 and FIGs. 4 and 5.

At 610, the UE may receive an indication (e.g., handover request) to switch from the current serving beam to the candidate beam from the base station in response to reporting the at least one modified beam measurement, such as described in connection with Table 1 and FIG. 5. The UE may perform the beam switching based on the indication, and may report a beam switching confirmation (e.g., handover complete) to the base station, such as described in connection with Table 1 and FIG. 5.

FIG. 7 is a diagram 700 illustrating an example of a hardware implementation for an apparatus 702. The apparatus 702 is a UE and includes a cellular baseband processor 704 (also referred to as a modem) coupled to a cellular RF transceiver 722 and one or more subscriber identity modules (SIM) cards 720, an application processor 706 coupled to a secure digital (SD) card 708 and a screen 710, a Bluetooth module 712, a wireless local area network (WLAN) module 714, a Global Positioning System (GPS) module 716, and a power supply 718. The cellular baseband processor 704 communicates through the cellular RF transceiver 722 with the UE 104 and/or BS 102/180. The cellular baseband processor 704 may include a computer-readable medium /memory. The cellular baseband processor 704 is responsible for general processing, including the execution of software stored on the computer-readable medium /memory. The software, when executed by the cellular baseband processor 704, causes the cellular baseband processor 704 to perform the various functions described supra. The computer-readable medium /memory may also be used for storing data that is manipulated by the cellular baseband processor 704 when executing software. The cellular baseband processor 704 further includes a reception component 730, a communication manager 732, and a transmission component 734. The communication manager 732 includes the one or more illustrated components. The components within the communication manager 732 may be stored in the computer-readable medium /memory and/or configured as hardware within the cellular baseband processor 704. The cellular baseband processor 704 may be a component of the UE 350 and may include the memory 360 and/or at least one of the TX processor 368, the RX processor 356, and the controller/processor 359. In one configuration, the apparatus 702 may be a modem chip and include just the baseband processor 704, and in another configuration, the apparatus 702 may be the entire UE (e.g., see 350 of FIG. 3) and include the aforediscussed additional modules of the apparatus 702.

The communication manager 732 includes a component 740 that is configured to perform beam measurements for a plurality of beams, e.g., as described in connection with 602 of FIG. 6. The communication manager 732 further includes a component 742 that is configured to determine that a candidate beam among the plurality of beams is better than a current serving beam of the UE, e.g., as described in connection with 604 of FIG. 6. The communication manager 732 further includes a component 744 that is configured to modify at least one beam measurement for one or more of the candidate beam and the current serving beam, e.g., as described in connection with 606 of FIG. 6. The communication manager 732 further includes a component 746 that is configured to report the at least one modified beam measurement to a base station, e.g., as described in connection with 608 of FIG. 6. The communication manager 732 further includes a component 748 that is configured to Receive an indication to switch from the current serving beam to the candidate beam from the base station in response to reporting the at least one modified beam measurement; and perform a beam switching based on the indication, e.g., as described in connection with 610 of FIG. 6.

The apparatus may include additional components that perform each of the blocks of the algorithm in the aforementioned flowcharts of FIG. 6. As such, each block in the aforementioned flowcharts of FIG. 6 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 702, and in particular the cellular baseband processor 704, includes means for performing beam measurements for a plurality of beams; means for determining that a candidate beam among the plurality of beams is better than a current serving beam of the UE; means for modifying at least one beam measurement for one or more of the candidate beam and the current serving beam; and means for reporting the at least one modified beam measurement to a base station. The aforementioned means may be one or more of the aforementioned components of the apparatus 702 configured to perform the functions recited by the aforementioned means. As described supra, the apparatus 702 may include the TX Processor 368, the RX Processor 356, and the controller/processor 359. As such, in one configuration, the aforementioned means may be the TX Processor 368, the RX Processor 356, and the controller/processor 359 configured to perform the functions recited by the aforementioned means.

The following examples are illustrative only and may be combined with aspects of other embodiments or teachings described herein, without limitation.

Example 1 is a method of wireless communication at a UE, comprising: performing beam measurements for a plurality of beams; determining that a candidate beam among the plurality of beams is better than a current serving beam of the UE; modifying at least one beam measurement for one or more of the candidate beam and the current serving beam; and reporting the at least one modified beam measurement to a base station.

In Example 2, the method of Example 1 further comprises: receiving an indication to switch from the current serving beam to the candidate beam from the base station in response to reporting the at least one modified beam measurement; and

performing a beam switching based on the indication.

In Example 3, the method of Example 1 or Example 2 further includes that the plurality of beams comprise the candidate beam and the current serving beam.

In Example 4, the method of any of Examples 1-3 further includes that the beam measurements include measurement of at least one of RSRP, CQI, PMI, CRI and RI of the plurality of beams.

In Example 5, the method of any of Examples 1-4 further includes that modifying the at least one beam measurement for one or more of the candidate beam and the current serving beam includes increasing a value of a measurement for the candidate beam.

In Example 6, the method of any of Examples 1-5 further includes that modifying the at least one beam measurement for one or more of the candidate beam and the current serving beam includes decreasing a value of a beam measurement for the serving beam.

In Example 7, the method of any of Examples 1-6 further includes that modifying the at least one beam measurement for one or more of the candidate beam and the current serving beam includes increasing a candidate beam measurement and decreasing a serving beam measurement.

In Example 8, the method of any of Examples 1-7 further includes that the UE determines the candidate beam is better than the current serving beam if the current serving beam’s beam measurement is below a threshold.

In Example 9, the method of any of Examples 1-8 further includes that the UE determines the candidate beam is better than the current serving beam if the current serving beam’s beam measurement is below a threshold and the candidate beam’s beam measurement is better than the current serving beam by an offset.

Example 10 is an apparatus for wireless communication at a UE, comprising: means for performing beam measurements for a plurality of beams; means for determining that a candidate beam among the plurality of beams is better than a current serving beam of the UE; means for modifying at least one beam measurement for one or more of the candidate beam and the current serving beam; and means for reporting the at least one modified beam measurement to a base station.

In Example 11, the method of Example 10 further comprises means to perform the method of any of Examples 2-9.

Example 12 is an apparatus for wireless communication at a UE, comprising: a memory; and at least one processor coupled to the memory, the memory and the at least one processor configured to perform the method of Examples 1-9.

Example 13 is a computer-readable medium storing computer executable code for wireless communication at a UE, the code when executed by a processor cause the processor to perform the method of any of Examples 1-9.

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. ” Terms such as “if, ” “when, ” and “while” should be interpreted to mean “under the condition that” rather than imply an immediate temporal relationship or reaction. That is, these phrases, e.g., “when, ” do not imply an immediate action in response to or during the occurrence of an action, but simply imply that if a condition is met then an action will occur, but without requiring a specific or immediate time constraint for the action to occur. The word “exemplary” is used herein to mean “serving as an example, instance, or illustration. ” Any aspect described herein as “exemplary” is not necessarily to be construed as preferred or advantageous over other aspects. Unless specifically stated otherwise, the term “some” refers to one or more. Combinations such as “at least one of A, B, or C, ” “one or more of A, B, or C, ” “at least one of A, B, and C, ” “one or more of A, B, and C, ” and “A, B, C, or any combination thereof” include any combination of A, B, and/or C, and may include multiples of A, multiples of B, or multiples of C. Specifically, combinations such as “at least one of A, B, or C, ” “one or more of A, B, or C, ” “at least one of A, B, and C, ” “one or more of A, B, and C, ” and “A, B, C, or any combination thereof” may be A only, B only, C only, A and B, A and C, B and C, or A and B and C, where any such combinations may contain one or more member or members of A, B, or C. 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. ”

Claims

A method of wireless communication at a user equipment (UE) , comprising:

performing beam measurements for a plurality of beams;

determining that a candidate beam among the plurality of beams is better than a current serving beam of the UE;

modifying at least one beam measurement for one or more of the candidate beam and the current serving beam; and

reporting the at least one modified beam measurement to a base station.
The method of claim 1, further comprising:

receiving an indication to switch from the current serving beam to the candidate beam from the base station in response to reporting the at least one modified beam measurement; and

performing a beam switching based on the indication.
The method of claim 1, wherein the plurality of beams comprise the candidate beam and the current serving beam.
The method of claim 1, wherein the beam measurements include measurement of at least one of reference signal receive power (RSRP) , channel quality indicator (CQI) , precoding matrix indicator (PMI) , CSI-RS resource indicator (CRI) and rank indicator (RI) of the plurality of beams.
The method of claim 1, wherein modifying the at least one beam measurement for one or more of the candidate beam and the current serving beam includes increasing a value of a measurement for the candidate beam.
The method of claim 1, wherein modifying the at least one beam measurement for one or more of the candidate beam and the current serving beam includes decreasing a value of a beam measurement for the serving beam.
The method of claim 1, wherein modifying the at least one beam measurement for one or more of the candidate beam and the current serving beam includes increasing a candidate beam measurement and decreasing a serving beam measurement.
The method of claim 1, wherein the UE determines the candidate beam is better than the current serving beam if the current serving beam’s beam measurement is below a threshold.
The method of claim 1, wherein the UE determines the candidate beam is better than the current serving beam if the current serving beam’s beam measurement is below a threshold and the candidate beam’s beam measurement is better than the current serving beam by an offset.
An apparatus for wireless communication at a user equipment (UE) , comprising:

means for performing beam measurements for a plurality of beams;

means for determining that a candidate beam among the plurality of beams is better than a current serving beam of the UE;

means for modifying at least one beam measurement for one or more of the candidate beam and the current serving beam; and

means for reporting the at least one modified beam measurement to a base station.
The apparatus of claim 10, further comprising means to perform the method of any of claims 2-9.
An apparatus for wireless communication at a user equipment (UE) , comprising:

a memory; and

at least one processor coupled to the memory, the memory and the at least one processor configured to perform the method of claims 1-9.
A computer-readable medium storing computer executable code for wireless communication at a user equipment (UE) , the code when executed by a processor cause the processor to perform the method of any of claims 1-9.