Methods and apparatuses for beam failure recovery enhancement
The method enhances beam failure recovery in wireless communication systems by adapting beam selection thresholds based on NES operation status, addressing challenges of dynamic spatial and power adaptations and improving energy efficiency and reliability.
Patent Information
- Application Number
- PCT/CN2024/110007
- Authority / Receiving Office
- WO · WO
- Patent Type
- Applications
- Current Assignee / Owner
- Priority Date
- 2023-08-09
- Filing Date
- 2024-08-06
- Publication Date
- 2025-02-13
AI Technical Summary
Current wireless communication systems, particularly in 5G NR, face challenges in efficiently managing beam failure recovery due to dynamic spatial and power adaptations, which can lead to unreliable link conditions and inefficient energy usage.
The proposed solution involves a method and apparatus for Beam Failure Recovery (BFR) enhancement, where a User Equipment (UE) receives an indication from a Base Station (BS) regarding the activation or deactivation of Network Energy Saving (NES) operations. Based on this indication, the UE applies different thresholds to select appropriate beams for BFR, using specific lists and power offset configurations to optimize energy efficiency and reliability.
This approach enhances the reliability of beam failure recovery procedures by adapting beam selection thresholds based on NES operation status, thereby improving connection reliability and supporting network energy optimization efforts.
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Figure CN2024110007_13022025_PF_FP_ABST
Abstract
Description
METHODS AND APPARATUSES FOR BEAM FAILURE RECOVERY ENHANCEMENT
[0001] CROSS-REFERENCE TO RELATED APPLICATION (S)
[0002] The present disclosure claims the benefit of and priority to U.S. Provisional Patent Application Serial No. 63 / 531,690, filed on August 9, 2023, entitled “METHOD TO ENHANCE NETWORK ENERGY SAVINGS FOR BEAM MANAGEMENT, ” the content of which is hereby incorporated herein fully by reference into the present application for all purposes.FIELD
[0003] The present disclosure is related to wireless communication and, more specifically, to methods and apparatuses for Beam Failure Recovery (BFR) enhancement.BACKGROUND
[0004] Various efforts have been made to improve different aspects of wireless communication for the cellular wireless communication systems, such as the 5th Generation (5G) New Radio (NR) system, by improving data rate, latency, reliability, and mobility. The 5G NR system is designed to provide flexibility and configurability to optimize network services and types, accommodating various use cases, such as enhanced Mobile Broadband (eMBB) , massive Machine-Type Communication (mMTC) , and Ultra-Reliable and Low-Latency Communication (URLLC) . As the demand for radio access continues to increase, however, there exists a need for further improvements in the art.SUMMARY
[0005] The present disclosure is related to methods and apparatuses for Beam Failure Recovery (BFR) enhancement.
[0006] According to a first aspect of the present disclosure, a method performed by a User Equipment (UE) for Beam Failure Recovery (BFR) enhancement is provided. The method includes receiving, from a Base Station (BS) , an indication of whether a Network Energy Saving (NES) operation is activated or deactivated by the BS, and performing a BFR procedure after receiving the indication. Performing the BFR procedure includes in response to the indication indicating that the NES operation is activated, applying a first threshold to select a first beam for the BFR procedure, and in response to the indication indicating that the NES operation is deactivated, applying a second threshold that is separated from the first threshold to select a second beam for the BFR procedure.
[0007] In some implementations of the first aspect of the present disclosure, applying the first threshold to select the first beam includes selecting, based on the first threshold, the first beam from a first list that is specifically configured for the NES operation.
[0008] In some implementations of the first aspect of the present disclosure, the method further includes receiving, from the BS, the first list via one of a broadcast message, a Medium Access Control (MAC) Control Element (CE) , and a Downlink Control Information (DCI) format.
[0009] In some implementations of the first aspect of the present disclosure, applying the second threshold to select the second beam includes selecting, based on the second threshold, the second beam from a second list that is not specifically configured for the NES operation.
[0010] In some implementations of the first aspect of the present disclosure, the method further includes determining the first threshold by multiplying the second threshold by a predetermined factor.
[0011] In some implementations of the first aspect of the present disclosure, the method further includes receiving, from the BS, a Channel State Information (CSI) report configuration including a first power offset value and a second power offset value, where the predetermined factor is a ratio of the first power offset value and the second power offset value.
[0012] In some implementations of the first aspect of the present disclosure, the method further includes receiving, from the BS, the first threshold via one of a Radio Resource Control (RRC) message, a Medium Access Control (MAC) Control Element (CE) , and a Downlink Control Information (DCI) format.
[0013] According to a second aspect of the present disclosure, a User Equipment (UE) for Beam Failure Recovery (BFR) enhancement is provided. The UE includes at least one processor and at least one non-transitory computer-readable medium coupled to the at least one processor. The at least one non-transitory computer-readable medium stores one or more computer-executable instructions that, when executed by the at least one processor, cause the UE to receive, from a Base Station (BS) , an indication of whether a Network Energy Saving (NES) operation is activated or deactivated by the BS, and perform a BFR procedure after receiving the indication. Performing the BFR procedure includes in response to the indication indicating that the NES operation is activated, applying a first threshold to select a first beam for the BFR procedure, and in response to the indication indicating that the NES operation is deactivated, applying a second threshold that is separated from the first threshold to select a second beam for the BFR procedure.
[0014] In some implementations of the second aspect of the present disclosure, applying the first threshold to select the first beam includes selecting, based on the first threshold, the first beam from a first list that is specifically configured for the NES operation.
[0015] In some implementations of the second aspect of the present disclosure, the one or more computer-executable instructions, when executed by the at least one processor, further cause the UE to receive, from the BS, the first list via one of a broadcast message, a Medium Access Control (MAC) Control Element (CE) , and a Downlink Control Information (DCI) format.
[0016] In some implementations of the second aspect of the present disclosure, applying the second threshold to select the second beam includes selecting, based on the second threshold, the second beam from a second list that is not specifically configured for the NES operation.
[0017] In some implementations of the second aspect of the present disclosure, the one or more computer-executable instructions, when executed by the at least one processor, further cause the UE to determine the first threshold by multiplying the second threshold by a predetermined factor.
[0018] In some implementations of the second aspect of the present disclosure, the one or more computer-executable instructions, when executed by the at least one processor, further cause the UE to receive, from the BS, a Channel State Information (CSI) report configuration including a first power offset value and a second power offset value, where the predetermined factor is a ratio of the first power offset value and the second power offset value.
[0019] In some implementations of the second aspect of the present disclosure, the one or more computer-executable instructions, when executed by the at least one processor, further cause the UE to receive, from the BS, the first threshold via one of a Radio Resource Control (RRC) message, a Medium Access Control (MAC) Control Element (CE) , and a Downlink Control Information (DCI) format.
[0020] According to a third aspect of the present disclosure, a Base Station (BS) for Beam Failure Recovery (BFR) enhancement is provided. The BS includes at least one processor and at least one non-transitory computer-readable medium coupled to the at least one processor. The at least one non-transitory computer-readable medium stores one or more computer-executable instructions that, when executed by the at least one processor, cause the BS to transmit, to a User Equipment (UE) , a first threshold and a second threshold, where the first threshold and the second threshold are separated parameters configured for a BFR procedure. The one or more computer-executable instructions that, when executed by the at least one processor, further cause the BS to transmit, to the UE, an indication of whether a Network Energy Saving (NES) operation is activated or deactivated by the BS, thereby enabling the UE to apply the first threshold to select a first beam for the BFR procedure in response to the indication indicating that the NES operation is activated and apply the second threshold to select a second beam for the BFR procedure in response to the indication indicating that the NES operation is deactivated.
[0021] In some implementations of the third aspect of the present disclosure, the one or more computer-executable instructions, when executed by the at least one processor, further cause the BS to transmit, to the UE, a first list that is specifically configured for the NES operation via one of a broadcast message, a Medium Access Control (MAC) Control Element (CE) , and a Downlink Control Information (DCI) format, thereby enabling the UE to select, based on the first threshold, the first beam from the first list in a case that the indication indicates that the NES operation is activated.
[0022] In some implementations of the third aspect of the present disclosure, the one or more computer-executable instructions, when executed by the at least one processor, further cause the BS to transmit, to the UE, a second list that is not specifically configured for the NES operation, thereby enabling the UE to select, based on the second threshold, the second beam from the second list in a case that the indication indicates that the NES operation is deactivated.
[0023] In some implementations of the third aspect of the present disclosure, the one or more computer-executable instructions, when executed by the at least one processor, further cause the BS to transmit, to the UE, the first threshold via one of a Radio Resource Control (RRC) message, a Medium Access Control (MAC) Control Element (CE) , and a Downlink Control Information (DCI) format.BRIEF DESCRIPTION OF THE DRAWINGS
[0024] Aspects of the present disclosure are best understood from the following detailed disclosure when read with the accompanying drawings. Various features are not drawn to scale. Dimensions of various features may be arbitrarily increased or reduced for clarity of discussion.
[0025] Figure 1 is a schematic diagram illustrating a format of a truncated BFR MAC CE, according to an example implementation of the present disclosure.
[0026] Figure 2 is a schematic diagram illustrating a format of a MAC CE that a UE may use to inform a network of a hypothetical beam failure reference ID before an actual NES adaptation, according to an example implementation of the present disclosure.
[0027] Figure 3 is a schematic diagram illustrating a time restriction for channel measurements, according to an example implementation of the present disclosure.
[0028] Figure 4 is a schematic diagram illustrating a time restriction for channel measurements, according to an example implementation of the present disclosure.
[0029] Figure 5 is a schematic diagram illustrating a time restriction for channel measurements, according to an example implementation of the present disclosure.
[0030] Figure 6 is a schematic diagram illustrating a format of an enhanced BFD RS indication MAC CE, according to an example implementation of the present disclosure.
[0031] Figure 7 is a flowchart illustrating a method / process for BFR enhancement, according to an example implementation of the present disclosure.
[0032] Figure 8 is a flowchart illustrating a method / process for BFR enhancement, according to an example implementation of the present disclosure.
[0033] Figure 9 is a block diagram illustrating a node for wireless communication, according to an example implementation of the present disclosure.DESCRIPTION
[0034] Some of the abbreviations in the present application are defined as follows and, unless otherwise specified, the abbreviations have the following meanings:
[0035] Abbreviation Full name
[0036] 3GPP 3rd Generation Partnership Project
[0037] 5G 5th Generation
[0038] 5GC 5G Core
[0039] ACK Acknowledgement
[0040] AL Aggregation Level
[0041] AN-PDB Access Network Packet Delay Budget
[0042] AS Access Stratum
[0043] ASN. 1 Abstract Syntax Notation One
[0044] BA Bandwidth Adaptation
[0045] BFD Beam Failure Detection
[0046] BFRQ Beam Failure Recovery Request
[0047] BFR Beam Failure Recovery
[0048] BLER Block Error Rate
[0049] BS Base Station
[0050] BSR Buffer Status Report
[0051] BWP Bandwidth Part
[0052] C-RNTI Cell Radio Network Temporary Identifier
[0053] CA Carrier Aggregation
[0054] CAG Closed Access Group
[0055] CB Codebook-Based
[0056] CCE Control Channel Element
[0057] CDM Code Division Multiplexing
[0058] CG Configured Grant
[0059] CJT Coherent Joint Transmission
[0060] CN Core Network
[0061] CN-PDB Core Network Packet Delay Budget
[0062] CORESET Control Resource Set
[0063] CPE Customer Premises Equipment
[0064] CRC Cyclic Redundancy Check
[0065] CSI Channel State Information
[0066] CSI-RS Channel State Information Reference Signal
[0067] CS-RNTI Configured Scheduling Radio Network Temporary Identifier
[0068] CSS Common Search Space
[0069] CU Central Unit
[0070] DAPS Dual Active Protocol Stack
[0071] DC Dual Connectivity
[0072] DCI Downlink Control Information
[0073] DG Dynamic Grant
[0074] DI Delay Information
[0075] DL Downlink
[0076] DL-SCH Downlink Shared Channel
[0077] DMRS Demodulation Reference Signal
[0078] DR Delay Report
[0079] DRB Data Radio Bearer
[0080] DTX Discontinuous Transmission
[0081] DRX Discontinuous Reception
[0082] DTCH Dedicated Traffic Channel
[0083] DU Distributed Unit
[0084] ETSI European Telecommunications Standards Institute
[0085] E-UTRA Evolved Universal Terrestrial Radio Access
[0086] EN-DC E-UTRA NR Dual Connectivity
[0087] EPC Evolved Packet Core
[0088] eMBB Enhanced Mobile BroadBand
[0089] eMTC Enhanced Machine Type Communication
[0090] eNB Evolved Node B
[0091] FDD Frequency Division Duplexing
[0092] FR Frequency Range
[0093] FR1 Frequency Range 1
[0094] FR2 Frequency Range 2
[0095] FWA Fixed Wireless Access
[0096] GC-PDCCH Group Common Physical Downlink Control Channel
[0097] GEO Geostationary Equatorial Orbit
[0098] gNB Next Generation Node B
[0099] GNSS Global Navigation Satellite System
[0100] GW Gateway
[0101] HARQ Hybrid Automatic Repeat Request
[0102] HO Handover
[0103] FR Frequency Range
[0104] IAB Integrated Access and Backhaul
[0105] ID Identity
[0106] IE Information Element
[0107] IoT Internet of Things
[0108] IIoT Industrial Internet of Things
[0109] ITS Intelligent Transportation System
[0110] ITU International Telecommunication Union
[0111] L1 Layer 1
[0112] L2 Layer 2
[0113] L3 Layer 3
[0114] LAN Local Area Network
[0115] LCH Logical Channel
[0116] LCID Logical Channel Identity
[0117] LEO Low Earth Orbit
[0118] LSB Least Significant Bit
[0119] LTE Long Term Evolution
[0120] LTM L1 / L2-Triggered Mobility
[0121] MAC Medium Access Control
[0122] MAC CE MAC Control Element
[0123] MCG Master Cell Group
[0124] MCS Modulation Coding Scheme
[0125] MCS-C-RNTI Modulation Coding Scheme Cell Radio Network Temporary Identifier
[0126] MIB Master Information Block
[0127] MIMO Multi-Input Multi-Output
[0128] mMTC Massive Machine Type Communications
[0129] MN Master Node
[0130] MSB Most Significant Bit
[0131] MTC Machine Type Communication
[0132] mTRP Multiple Transmission Reception Points
[0133] NACK Negative Acknowledgement
[0134] NAS Non-Access Stratum
[0135] NB-IoT Narrow Band Internet of Things
[0136] NCB Non-Codebook-Based
[0137] NDI New Data Indicator
[0138] NES Network Energy Saving
[0139] NPN Non-Public Network
[0140] NR New Radio
[0141] NR-U NR Unlicensed
[0142] NTN Non-Terrestrial Network
[0143] NW Network
[0144] NZP Non-Zero-Power
[0145] PBCH Physical Broadcast Channel
[0146] PCell Primary Cell
[0147] PCI Physical Cell Identity
[0148] PDB Packet Delay Budget
[0149] PDCCH Physical Downlink Control Channel
[0150] PDCP Packet Data Convergence Protocol
[0151] PDSCH Physical Downlink Shared Channel
[0152] PDU Protocol Data Unit
[0153] PHY Physical
[0154] PLMN Public Land Mobile Network
[0155] PNI-NPN Public Network Integrated Non-Public Network
[0156] PRACH Physical Random Access Channel
[0157] PRB Physical Resource Block
[0158] PSCell Primary Secondary Cell
[0159] PSDB PDU Set Delay Budget
[0160] PTAG Primary Timing Advance Group
[0161] PTRS Phase Tracking Reference Signal
[0162] PUCCH Physical Uplink Control Channel
[0163] PUSCH Physical Uplink Shared Channel
[0164] QCL Quasi-CoLocation
[0165] QoS Quality of Service
[0166] RA Random Access
[0167] RACH Random Access Channel
[0168] RAN Radio Access Network
[0169] RAR Random Access Response
[0170] RAT Radio Access Technology
[0171] RE Resource Element
[0172] Rel-15 Release 15
[0173] Rel-16 Release 16
[0174] RF Radio Frequency
[0175] RLC Radio Link Control
[0176] RS Reference Signal
[0177] RLF Radio Link Failure
[0178] RSTD Reference Signal Time Difference Measurement
[0179] RNTI Radio Network Temporary Identifier
[0180] RO RACH Occasion
[0181] RRC Radio Resource Control
[0182] RRM Radio Resource Measurement
[0183] RS Reference Signal
[0184] RSRP Reference Signal Received Power
[0185] RSRQ Reference Signal Receiving Quality
[0186] RX Reception
[0187] SCell Secondary Cell
[0188] SCG Secondary Cell Group
[0189] SDM Spatial Division Multiplexing
[0190] SDT Small Data Transmission
[0191] SFN Single Frequency Network
[0192] SI System Information
[0193] SIB System Information Block
[0194] SINR Signal to Interference plus Noise Ratio
[0195] SL Sidelink
[0196] SLIV Start and Length Indicator Value
[0197] SN Secondary Node
[0198] SNPN Stand-alone Non-Public Network
[0199] SpCell Special Cell
[0200] SR Scheduling Request
[0201] SRB Signaling Radio Bearer
[0202] SRS Sounding Reference Signal
[0203] SRI SRS Resource Indicator
[0204] SSB Synchronization Signal Block
[0205] STAG Secondary Timing Advance Group
[0206] sTRP Single Transmission Reception Point
[0207] STxMP Simultaneous Transmission on Multiple Panels
[0208] SUL Supplementary Uplink
[0209] TA Timing Advance
[0210] TAG Timing Advance Group
[0211] TAT Time Alignment Timer
[0212] TB Transport Block
[0213] TCI Transmission Configuration Indication
[0214] TDD Time Division Duplexing
[0215] TN Terrestrial Network
[0216] TPC Transmission Power Control
[0217] TPMI Transmit Precoder Matrix Indication
[0218] TRP Transmission Reception Point
[0219] TRS Tracking Reference Signal
[0220] TS Technical Specification
[0221] TX Transmission
[0222] UCI Uplink Control Information
[0223] UE User Equipment
[0224] UL Uplink
[0225] UL-CG Uplink-Configured Grant
[0226] UPF User Plane Function
[0227] URLLC Ultra-Reliable and Low-Latency Communications
[0228] USIM Universal Subscriber Identity Module
[0229] USS UE-specific Search Space
[0230] V2X Vehicle-to-Everything
[0231] VSAT Very Small Aperture Terminal
[0232] XR Extended Reality
[0233] The following contains specific information related to implementations of the present disclosure. The drawings and their accompanying detailed disclosure are merely directed to implementations. However, the present disclosure is not limited to these implementations. Other variations and implementations of the present disclosure will be obvious to those skilled in the art.
[0234] Unless noted otherwise, like or corresponding elements among the drawings may be indicated by like or corresponding reference numerals. Moreover, the drawings and illustrations in the present disclosure are generally not to scale and are not intended to correspond to actual relative dimensions.
[0235] For consistency and ease of understanding, like features may be identified (although, in some examples, not illustrated) by the same numerals in the drawings. However, the features in different implementations may be different in other respects and shall not be narrowly confined to what is illustrated in the drawings.
[0236] References to “one implementation, ” “an implementation, ” “example implementation, ” “various implementations, ” “some implementations, ” “implementations of the present application, ” etc., may indicate that the implementation (s) of the present application so described may include a particular feature, structure, or characteristic, but not every possible implementation of the present application necessarily includes the particular feature, structure, or characteristic. Further, repeated use of the phrase “in one implementation, ” or “in an example implementation, ” “an implementation, ” do not necessarily refer to the same implementation, although they may. Moreover, any use of phrases like “implementations” in connection with “the present application” are never meant to characterize that all implementations of the present application must include the particular feature, structure, or characteristic, and should instead be understood to mean “at least some implementations of the present application” includes the stated particular feature, structure, or characteristic. The term “coupled” is defined as connected, whether directly or indirectly through intervening components, and is not necessarily limited to physical connections. The term “comprising, ” when utilized, means “including, but not necessarily limited to” ; it specifically indicates open-ended inclusion or membership in the so-described combination, group, series, and the equivalent.
[0237] The expression “at least one of A, B and C” or “at least one of the following: A, B and C” means “only A, or only B, or only C, or any combination of A, B and C. ” The terms “system” and “network” may be used interchangeably. The term “and / or” is only an association relationship for describing associated objects and represents that three relationships may exist such that A and / or B may indicate that A exists alone, A and B exist at the same time, or B exists alone. The character “ / ” generally represents that the associated objects are in an “or” relationship.
[0238] For the purposes of explanation and non-limitation, specific details, such as functional entities, techniques, protocols, and standards, are set forth for providing an understanding of the disclosed technology. In other examples, detailed disclosure of well-known methods, technologies, systems, and architectures are omitted so as not to obscure the present disclosure with unnecessary details.
[0239] Persons skilled in the art will immediately recognize that any network function (s) or algorithm (s) disclosed may be implemented by hardware, software, or a combination of software and hardware. Disclosed functions may correspond to modules which may be software, hardware, firmware, or any combination thereof.
[0240] A software implementation may include computer executable instructions stored on a computer-readable medium, such as memory or other type of storage devices. One or more microprocessors or general-purpose computers with communication processing capability may be programmed with corresponding executable instructions and perform the disclosed network function (s) or algorithm (s) .
[0241] The microprocessors or general-purpose computers may include Application-Specific Integrated Circuits (ASICs) , programmable logic arrays, and / or one or more Digital Signal Processor (DSPs) . Although some of the disclosed implementations are oriented to software installed and executing on computer hardware, alternative implementations implemented as firmware, as hardware, or as a combination of hardware and software are well within the scope of the present disclosure. The computer-readable medium includes but is not limited to Random Access Memory (RAM) , Read Only Memory (ROM) , Erasable Programmable Read-Only Memory (EPROM) , Electrically Erasable Programmable Read-Only Memory (EEPROM) , flash memory, Compact Disc Read-Only Memory (CD-ROM) , magnetic cassettes, magnetic tape, magnetic disk storage, or any other equivalent medium capable of storing computer-readable instructions.
[0242] A radio communication network architecture such as a Long-Term Evolution (LTE) system, an LTE-Advanced (LTE-A) system, an LTE-Advanced Pro system, or a 5G NR Radio Access Network (RAN) typically includes at least one base station (BS) , at least one UE, and one or more optional network elements that provide connection within a network. The UE communicates with the network such as a Core Network (CN) , an Evolved Packet Core (EPC) network, an Evolved Universal Terrestrial RAN (E-UTRAN) , a 5G Core (5GC) , or an internet via a RAN established by one or more BSs.
[0243] A UE may include, but is not limited to, a mobile station, a mobile terminal or device, or a user communication radio terminal. The UE may be a portable radio equipment that includes, but is not limited to, a mobile phone, a tablet, a wearable device, a sensor, a vehicle, or a Personal Digital Assistant (PDA) with wireless communication capability. The UE is configured to receive and transmit signals over an air interface to one or more cells in a RAN.
[0244] The BS may be configured to provide communication services according to at least a Radio Access Technology (RAT) such as Worldwide Interoperability for Microwave Access (WiMAX) , Global System for Mobile communications (GSM) that is often referred to as 2G, GSM Enhanced Data rates for GSM Evolution (EDGE) RAN (GERAN) , General Packet Radio Service (GPRS) , Universal Mobile Telecommunication System (UMTS) that is often referred to as 3G based on basic wideband-code division multiple access (W-CDMA) , high-speed packet access (HSPA) , LTE, LTE-A, evolved LTE (eLTE) that is LTE connected to 5GC, NR (often referred to as 5G) , and / or LTE-APro. However, the scope of the present disclosure is not limited to these protocols.
[0245] The BS may include, but is not limited to, a node B (NB) in the UMTS, an evolved node B (eNB) in LTE or LTE-A, a radio network controller (RNC) in UMTS, a BS controller (BSC) in the GSM / GERAN, an ng-eNB in an Evolved Universal Terrestrial Radio Access (E-UTRA) BS in connection with 5GC, a next generation Node B (gNB) in the 5G-RAN, or any other apparatus capable of controlling radio communication and managing radio resources within a cell. The BS may serve one or more UEs via a radio interface.
[0246] The BS is operable to provide radio coverage to a specific geographical area using multiple cells forming the RAN. The BS supports the operations of the cells. Each cell is operable to provide services to at least one UE within its radio coverage.
[0247] Each cell (often referred to as a serving cell) provides services to serve one or more UEs within its radio coverage such that each cell schedules the DL and optionally UL resources to at least one UE within its radio coverage for DL and optionally UL packet transmissions. The BS may communicate with one or more UEs in the radio communication system via the cells.
[0248] A cell may allocate sidelink (SL) resources for supporting Proximity Service (ProSe) or Vehicle to Everything (V2X) service. Each cell may have overlapped coverage areas with other cells.
[0249] In Multi-RAT Dual Connectivity (MR-DC) cases, the primary cell of a Master Cell Group (MCG) or a Secondary Cell Group (SCG) may be called a Special Cell (SpCell) . A Primary Cell (PCell) may include the SpCell of an MCG. A Primary SCG Cell (PSCell) may include the SpCell of an SCG. MCG may include a group of serving cells associated with the Master Node (MN) , including the SpCell and optionally one or more Secondary Cells (SCells) . An SCG may include a group of serving cells associated with the Secondary Node (SN) , including the SpCell and optionally one or more SCells.
[0250] As discussed above, the frame structure for NR supports flexible configurations for accommodating various next generation (e.g., 5G) communication requirements, such as Enhanced Mobile Broadband (eMBB) , Massive Machine Type Communication (mMTC) , and Ultra-Reliable and Low-Latency Communication (URLLC) , while fulfilling high reliability, high data rate, and low latency requirements. The Orthogonal Frequency-Division Multiplexing (OFDM) technology in the 3GPP may serve as a baseline for an NR waveform. The scalable OFDM numerology, such as adaptive sub-carrier spacing, channel bandwidth, and Cyclic Prefix (CP) , may also be used.
[0251] Two coding schemes are considered for NR, specifically Low-Density Parity-Check (LDPC) code and Polar Code. The coding scheme adaption may be configured based on channel conditions and / or service applications.
[0252] At least DL transmission data, a guard period, and UL transmission data should be included in a transmission time interval (TTI) of a single NR frame. The respective portions of the DL transmission data, the guard period, and the UL transmission data should also be configurable based on, for example, the network dynamics of NR. SL resources may also be provided in an NR frame to support ProSe services or V2X services.
[0253] Any two or more than two of the following paragraphs, (sub) -bullets, points, actions, behaviors, terms, or claims described in the present disclosure may be combined logically, reasonably, and properly to form a specific method.
[0254] Any sentence, paragraph, (sub) -bullet, point, action, behaviors, terms, or claims described in the present disclosure may be implemented independently and separately to form a specific method.
[0255] Dependency, e.g., “based on” , “more specifically” , “preferably” , “in one embodiment” , “in some implementations” , etc., in the present disclosure is just one possible example which would not restrict the specific method.
[0256] “Aand / or B” in the present disclosure may refer to either A or B, both A and B, or at least one of A and B.
[0257] The terms, definitions, and abbreviations included in the present disclosure are either sourced from existing documents (such as those from ETSI, ITU, or other sources) or newly created by experts from the 3GPP whenever there was a need for precise vocabulary.
[0258] In the present disclosure, although the term “gNB” is used throughout the document as an example of a base station, it should be understood that the term “gNB” may be replaced by any other type of BS (e.g., an eNB) . Moreover, the terms “TRP, ” “beam, ” and “panel” may be used interchangeably. Additionally, the term “overlap” may include a partial overlapping or a full overlapping in the time domain and / or the frequency domain.
[0259] Examples of some selected terms in the present disclosure are provided as follows.
[0260] Antenna Panel: A conceptual term for a UE antenna implementation. It may be assumed that a panel is an operational unit for controlling a transmitting spatial filter (beam) . A panel may typically include multiple antenna elements. In one implementation, a beam may be formed by a panel, and in order to form two beams simultaneously, two panels may be needed. Such simultaneous beamforming from multiple panels may be subject to UE capability. A similar definition for “panel” may be applicable by applying spatial receiving filtering characteristics. The UE panel information may be derived from the TCI state / UL beam indication information or from the network signaling.
[0261] Beam: A beam may refer to a spatial (domain) filtering. In one example, the spatial filtering may be applied in the analog domain by adjusting a phase and / or an amplitude of a signal before being transmitted by a corresponding antenna element. In another example, the spatial filtering may be applied in the digital domain by the Multi-Input Multi-Output (MIMO) technique in the wireless communication system. For example, “aUE made a PUSCH transmission by using a specific beam” may imply that the UE made the PUSCH transmission by using the specific spatial / digital domain filter. The “beam” may also be, but is not limited to be, represented as an antenna, an antenna port, an antenna element, a group of antennas, a group of antenna ports, or a group of antenna elements. The beam may also be formed by a certain reference signal resource. In short, the beam may be equivalent to a spatial domain filter through which the EM wave is radiated. Beam information may include details about the selected or utilized beam or spatial filter. In some implementations, the individual beams (e.g., spatial filters) may be used to transmit individual reference signals. Consequently, a beam or beam information may be represented by one or more reference signal resource indices.
[0262] CA: In Carrier Aggregation (CA) , two or more Component Carriers (CCs) may be aggregated. A UE may simultaneously receive or transmit on one or multiple CCs depending on its capabilities. CA may be supported for both contiguous and non-contiguous CCs. When CA is deployed, the frame timing and SFN may be aligned across cells that are capable of aggregation. The maximum number of configured CCs for a UE may be 16 for DL and 16 for UL. When CA is configured, the UE may only have one RRC connection with the network. At the RRC connection establishment / re-establishment / handover, a serving cell may provide the NAS mobility information, and at the RRC connection re-establishment / handover, a serving cell may provide the security input. Such a cell may be referred to as the Primary Cell (PCell) . Depending on the UE capabilities, Secondary Cells (SCells) may be configured to form, together with the PCell, a set of serving cells. Therefore, the configured set of serving cells for a UE may always include one PCell and one or more SCells.
[0263] BWP: A subset of the total cell bandwidth of a cell is referred to as a Bandwidth Part (BWP) and a Bandwidth Adaptation (BA) may be achieved by configuring the UE with BWP (s) and instructing the UE which of the configured BWPs is currently the active one. To enable a BA on the PCell, the gNB configures the UE with UL and DL BWP (s) . To enable the BA on SCells, in case of CA, the gNB configures the UE with one or more DL BWPs (e.g., there may be no BWP in the UL) . For the PCell, the initial BWP is the BWP used for an initial access. For the SCell (s) , the initial BWP is the BWP configured for the UE to operate after an SCell activation. The UE may be configured with a first active uplink BWP by a firstActiveUplinkBWP IE. If the first active uplink BWP is configured for an SpCell, the firstActiveUplinkBWP IE field may contain the ID of the UL BWP to be activated upon performing the RRC (re-) configuration. If the field is absent, the RRC (re-) configuration does not impose a BWP switching. If the first active uplink BWP is configured for an SCell, the firstActiveUplinkBWP IE field may contain the ID of the uplink bandwidth part to be used upon the MAC-activation of an SCell.
[0264] DCI: DCI may include downlink control information, and there may be various DCI formats used in a PDCCH. The DCI format may be a predefined format in which the downlink control information may be packed / formed and transmitted in a PDCCH.
[0265] TCI state: A TCI state may include parameters for configuring a QCL relationship between one or more DL reference signals and a target reference signal set. For example, a target reference signal set may include the DMRS ports of a PDSCH, a PDCCH, a PUCCH, or a PUSCH. The reference signals may include UL or DL reference signals. In NR Rel-15 / 16, the TCI state may be used for a DL QCL indication, whereas the spatial relation information may be used for providing the UL spatial transmission filter information for the UL signal (s) or channel (s) . A TCI state may include the information similar to the spatial relation information, which may be used for UL transmission. In other words, from the UL perspective, a TCI state may provide the UL beam information that may indicate the relationship between a UL transmission and the DL or UL reference signals (e.g., the CSI-RS, the SSB, the SRS, and the PTRS) .
[0266] HARQ: A functionality that ensures the delivery between peer entities at Layer 1 (e.g., Physical Layer) . A single HARQ process may support one Transport Block (TB) when the physical layer is not configured for the downlink / uplink spatial multiplexing, and when the physical layer is configured for downlink / uplink spatial multiplexing, a single HARQ process may support one or more TBs. There may be one HARQ entity per serving cell. Each HARQ entity may support a parallel (number of) DL and UL HARQ process.
[0267] PCell: When CA is configured, the UE may have only one RRC connection with the network. During the RRC connection establishment / re-establishment / handover procedure, a serving cell may provide the NAS mobility information. Additionally, during the RRC connection re-establishment / handover procedure, a serving cell may provide the security input. The serving cell may be referred to as a PCell.
[0268] PUCCH SCell: When CA is configured, the UE may be configured with a cell other than PCell on which a PUCCH resource may be configured. The cell may be referred to as a PUCCH SCell.
[0269] CSI-ReportConfig: An information element that represents, or specifies details of, a CSI report configuration. For example, the CSI-ReportConfig IE may contain a variety of IEs organized in a hierarchical structure. At the top level, the CSI-ReportConfig IE may include IEs such as the reportConfigId IE, the carrier IE, the resourcesForChannelMeasurement IE, the csi-IM-ResourcesForInterference IE, the nzp-CSI-RS-ResourcesForInterference IE, the reportConfigType IE, the reportQuantity IE, the reportFreqConfiguration IE, the codebookConfig IE, and the cqi-Table IE. The reportConfigType IE may offer a choice between four IEs: the periodic IE, the semiPersistentOnPUCCH IE, the semiPersistentOnPUSCH IE, and the aperiodic IE. Each of the four IEs may have associated sub-elements. The periodic IE and the semiPersistentOnPUCCH IE may both include the reportSlotConfig IE and the pucch-CSI-ResourceList IE. The semiPersistentOnPUSCH IE may include the reportSlotConfig IE, the reportSlotOffsetList IE, and the p0alpha IE. The aperiodic IE may include the reportSlotOffsetList IE.
[0270] The following describes the some of the above-mentioned IEs within the CSI-ReportConfig IE:
[0271] carrier: This IE may indicate in which serving cell the CSI-ResourceConfig IE may be found. If the carrier IE is absent, the resources may be on the same serving cell as the CSI report configuration (e.g., the CSI-ReportConfig IE) .
[0272] codebookConfig: This IE may specify the codebook configuration for Type-1 or Type-2. The codebook configuration may include a codebook subset restriction. If the field codebookConfig-r16 is present, the UE may ignore the codebookConfig IE (without suffix) .
[0273] cqi-Table: This IE may indicate which CQI table to use for CQI calculation.
[0274] csi-IM-ResourcesForInterference: This IE may specify the CSI Interference Measurement (IM) resources for interference measurement. This IE may indicate the CSI resource configuration ID (e.g., the csi-ResourceConfigId IE) of the CSI resource configuration (e.g., the CSI-ResourceConfig IE) included in the configuration of the serving cell indicated by the carrier IE, where the CSI-ResourceConfig IE may contain only CSI IM resources, and the BWP ID (e.g., the bwp-Id IE) contained in the CSI-ResourceConfig IE may be the same as the bwp-Id IE in the CSI-ResourceConfig IE indicated by the resourcesForChannelMeasurement IE.
[0275] nzp-CSI-RS-ResourcesForInterference: This IE may specify the NZP CSI-RS resources for interference measurement. This IE may indicate the csi-ResourceConfigId IE of the CSI-ResourceConfig IE included in the configuration of the serving cell indicated by the carrier IE, where the CSI-ResourceConfig IE may contain only NZP-CSI-RS resources, and the bwp-Id IE in the CSI-ResourceConfig IE may be the same as the bwp-Id IE in the CSI-ResourceConfig IE indicated by the resourcesForChannelMeasurement IE.
[0276] pucch-CSI-ResourceList: This IE may indicate which PUCCH resource to use for reporting on a PUCCH.
[0277] reportConfigType: This IE may specify the time domain behavior of the CSI report configuration (e.g., the CSI-ReportConfig IE) .
[0278] reportFreqConfiguration: This IE may represent, or specify details of, the CSI report configuration (e.g., the CSI-ReportConfig IE) in the frequency domain.
[0279] reportQuantity: This IE may specify the CSI-related quantities to report. If another IE, such as the reportQuantity-r16 IE, is present, the UE may ignore the reportQuantity IE (without suffix) .
[0280] reportSlotConfig: This IE may specify the periodicity and slot offset. If another IE, such as the reportSlotConfig-v1530 IE, is present, the UE may ignore the value provided in the reportSlotConfig IE (without suffix) .
[0281] reportSlotOffsetList, reportSlotOffsetListForDCI-Format0-1, reportSlotOffsetListForDCI-Format0-2: These IEs may specify the timing offset Y for semi persistent reporting using a PUSCH. These IEs may list the allowed offset values. Additionally, the lists in these IEs may have the same number of entries as the pusch-TimeDomainAllocationList IE in the PUSCH-Config IE. A particular value may be indicated in the DCI. The network may use the DCI field of a UL grant to indicate which of the configured report slot offsets the UE should apply. For example, the DCI values may correspond to the report slot offsets in the list sequentially. The DCI value 0 may correspond to the first report slot offset in the list, the DCI value 1 may correspond to the second report slot offset in the list, and so on for subsequent value. The first report may be transmitted in slot n+Y, and the second report may be transmitted in slot n+Y+P, where P may be the configured periodicity. For aperiodic reporting using a PUSCH, the timing offset Y may be specified. The list of allowed offset values may have the same number of entries as the list specified by the pusch-TimeDomainAllocationList IE in the PUSCH-Config IE. The network may use the DCI field of the UL grant to indicate which of the configured report slot offsets the UE should apply. For example, the DCI values may correspond to the report slot offsets in the list sequentially. The DCI value 0 may correspond to the first report slot offset in the list, the DCI value 1 may correspond to the second report slot offset in the list, and so on for subsequent value. The reportSlotOffsetList IE may correspond to the DCI format 0_0. The reportSlotOffsetListForDCI-Format0-1 IE may correspond to the DCI format 0_1. The reportSlotOffsetListForDCI-Format0-2 IE may correspond to DCI format 0_2.
[0282] resourcesForChannelMeasurement: This IE may specify the resources for channel measurement. This IE may indicate the csi-ResourceConfigId IE of the CSI-ResourceConfig IE included in the configuration of the serving cell indicated by the carrier IE, where the CSI-ResourceConfig IE may contain only NZP-CSI-RS resources and / or SSB resources. The CSI-ReportConfig IE may be associated with the DL BWP indicated by the bwp-Id IE contained in the CSI-ResourceConfig IE.
[0283] CSI-AperiodicTriggerState: The CSI-AperiodicTriggerState IE may contain a variety of IEs organized in a hierarchical structure. At the top level, the CSI-AperiodicTriggerState IE may include one or more elements of the CSI-AssociatedReportConfigInfo IE. Each CSI-AssociatedReportConfigInfo IE may include several sub-elements such as the reportConfigId IE, the resourcesForChannel IE, the csi-IM-ResourcesForInterference IE, and the nzp-CSI-RS-ResourcesForInterference IE. The resourcesForChannel IE may offer a choice between two IEs: the nzp-CSI-RS IE and the csi-SSB-ResourceSet IE. The nzp-CSI-RS IE may contain two sub-elements: the resourceSet IE and the qcl-info IE.
[0284] The following describes the some of the above-mentioned IEs within the CSI-AperiodicTriggerState IE:
[0285] csi-IM-ResourcesForInterference: This IE may specify a CSI IM resource set for interference measurement. This IE may indicate the entry number in the csi-IM-ResourceSetList IE in the CSI-ResourceConfig IE indicated by the csi-IM-ResourcesForInterference IE in the CSI-ReportConfig IE indicated by the reportConfigId IE (e.g., value 1 corresponds to the first entry, value 2 to the second entry, and so on) . The indicated CSI IM Resource Set (e.g., the indicated CSI-IM-ResourceSet IE) may have exactly the same number of resources as the NZP-CSI-RS-ResourceSet IE indicated in the nzp-CSI-RS-ResourcesforChannel IE.
[0286] csi-SSB-ResourceSet: This IE may specify va CSI SSB resource set for channel measurements. This IE may indicate the entry number in the csi-SSB-ResourceSetList IE in the CSI-ResourceConfig IE indicated by the resourcesForChannelMeasurement IE in the CSI-ReportConfig IE indicated by the reportConfigId IE (e.g., value 1 corresponds to the first entry, value 2 to the second entry, and so on) .
[0287] nzp-CSI-RS-ResourcesForInterference: This IE may specify the NZP CSI-RS resource set for interference measurement. This IE may indicate the entry number in the nzp-CSI-RS-ResourceSetList IE in the CSI-ResourceConfig IE indicated by the nzp-CSI-RS-ResourcesForInterference IE in the CSI-ReportConfig IE indicated by the reportConfigId IE (e.g., value 1 corresponds to the first entry, value 2 to the second entry, and so on) .
[0288] qcl-info: This IE may provide a list of references to the TCI states for providing the QCL source and the QCL type for each NZP CSI-RS resource listed in the nzp-CSI-RS-Resources IE of the NZP-CSI-RS-ResourceSet IE indicated by the nzp-CSI-RS-ResourcesforChannel IE. Each TCI state IE, such as the TCI-StateId IE, may correspond to a specific TCI state. The value of the TCI-StateId IE for the specific TCI state may be defined in the tci-StatesToAddModList IE of the PDSCH-Config IE that is included in the BWP-Downlink IE. The BWP-Downlink IE may correspond to the serving cell and to the DL BWP to which the resourcesForChannelMeasurement IE (in the CSI-ReportConfig IE indicated by the reportConfigId IE) belong. The entries in the qcl-info-forChannel IE may be one-to-one mapped to the entries in the nzp-CSI-RS-Resources IE of the NZP-CSI-RS-ResourceSet IE. For example, the first entry in the qcl-info-forChannel IE may correspond to the first entry in the nzp-CSI-RS-Resources IE of the NZP-CSI-RS-ResourceSet IE, the second entry in the qcl-info-forChannel IE may correspond to the second entry in the nzp-CSI-RS-Resources IE of the same NZP-CSI-RS-ResourceSet IE, and so on.
[0289] reportConfigId: This IE may specify a report configuration ID of a CSI report configuration specified in the CSI-ReportConfigToAddMod IE in the CSI-MeasConfig IE.
[0290] resourceSet: This IE may specify the NZP CSI-RS resource set for channel measurements. This IE may indicate the entry number in the nzp-CSI-RS-ResourceSetList IE in the CSI-ResourceConfig IE indicated by the resourcesForChannelMeasurement IE in the CSI-ReportConfig IE indicated by the reportConfigId IE (e.g., value 1 corresponds to the first entry, value 2 to the second entry, and so on) .
[0291] Network energy saving may be crucial for reducing environmental impact, such as greenhouse gas emissions. Keeping the environmental impact of 5G under control may be essential. Solutions that may improve network energy efficiency may need to be developed.
[0292] In NR systems, enhancing beam management and beam failure procedures may need consideration when accounting for spatial pattern adaptation. Legacy beam procedures may be inefficient due to dynamic spatial and power adaptation. Enhanced beam procedures corresponding to dynamic adaptation may need support.
[0293] CSI Framework
[0294] The BS (e.g., gNB) may control the time and frequency resources that the UE may use to report CSI. The CSI (or CSI report) may include a Channel Quality Indicator (CQI) , a Precoding Matrix Indicator (PMI) , a CSI-RS Resource Indicator (CRI) , an SS / PBCH Block Resource Indicator (SSBRI) , a Layer Indicator (LI) , a Rank Indicator (RI) , an L1-RSRP value, and / or an L1-SINR value.
[0295] A UE may be configured by higher layers with N≥1 reporting settings (N may be the number of reporting settings) for the CSI-ReportConfig IE, M≥1 resource settings (M may be the number of resource settings) for the CSI-ResourceConfig IE, and one or two lists including one or more trigger states. These trigger states may be given by the higher layer parameters / IEs, such as the CSI-AperiodicTriggerStateList IE and the CSI-SemiPersistentOnPUSCH-TriggerStateList IE.
[0296] Each trigger state in the CSI-AperiodicTriggerStateList IE may include a list of associated CSI report configurations (e.g., a list of the associated IE CSI-ReportConfig) indicating the resource set IDs for channel and optionally for interference. Each trigger state in the CSI-SemiPersistentOnPUSCH-TriggerStateList IE may be associated with a CSI report configuration (e.g., the CSI-ReportConfig IE) .
[0297] Each reporting setting specified by the CSI report configuration (e.g., the CSI-ReportConfig IE) may be associated with a single DL BWP (e.g., identified by the BWP-Id IE) that is indicated by the associated CSI-ResourceConfig IE for channel measurement. The CSI-ReportConfig IE may include the parameter (s) for a CSI reporting band: the codebook configuration including a codebook subset restriction, the time-domain behavior, the frequency granularity for CQI and PMI, the measurement restriction configurations, and the CSI-related quantities to be reported by the UE such as the LI, the L1-RSRP value, the L1-SINR value, the CRI, and the SSBRI.
[0298] Each CSI resource setting specified by the CSI resource configuration (e.g., the CSI-ResourceConfig IE) may include a configuration of a list of S≥1 CSI resource sets (Smay be the number of resource sets) . This list may be indicated by the higher layer parameter, such as the csi-RS-ResourceSetList IE. The list may include references to either or both of the NZP CSI-RS resource set (s) and the SS / PBCH block set (s) , or may include references to the CSI-IM resource set (s) . Each CSI resource setting may be located in the DL BWP that is identified by the BWP-id IE. All CSI resource settings linked to a CSI report setting may correspond to the same DL BWP.
[0299] A trigger state may be initiated using a CSI request field in the DCI. If all bits of the CSI request field in the DCI are set to zero, no CSI may be requested. If the number of configured (CSI) trigger states in the CSI-AperiodicTriggerStateList IE is greater than where NTS is the number of bits in the CSI request field in the DCI, the UE may receive a sub-selection indication. The sub-selection indication may map up to trigger states to the CSI request field codepoints in the DCI. NTS may be configured by a higher layer parameter, such as the reportTriggerSize IE. If the number of (CSI) trigger states in the CSI-AperiodicTriggerStateList IE is less than, or equal to, the CSI request field in the DCI may directly indicate the trigger state.
[0300] For the aperiodic CSI-RS reporting procedure, the CSI-RS offset may be configured per resource set by a higher layer parameter, such as the aperiodicTriggeringOffset IE. This may apply even when the UE is not configured with the minimumSchedulingOffset IE for any DL or UL BWP, and all associated trigger states do not have the higher layer parameter, qcl-Type, set to QCL-TypeD in the corresponding TCI states. The CSI-RS triggering offset may be {0, 1, 2, 3, 4, 16, 24} slots. If the UE is not configured with the minimumSchedulingOffset IE for any DL or UL BWP, and all associated trigger states do not have the higher layer parameter, qcl-Type, set to QCL-TypeD in the corresponding TCI states, the CSI-RS triggering offset may be fixed to zero. The CSI-IM aperiodic triggering offset may follow the associated NZP CSI-RS offset for channel measurement.
[0301] The PUSCH resource for reporting the A-CSI may be indicated by the DCI that triggers the A-CSI reporting procedure. The PRBs for the PUSCH may be indicated in the Frequency Domain Resource Assignment (FDRA) field of the DCI. The symbols for the PUSCH may be indicated by the Time Domain Resource Assignment (TDRA) field of the DCI. The UL-SCH indicator field in the DCI may indicate whether the A-CSI is multiplexed with the UL-SCH. If the UL-SCH indicator field is set to ‘1’ , the A-CSI may be multiplexed with the UL-SCH, and the number of REs for the A-CSI may be calculated. The slot n+K2 in which the PUSCH is transmitted may be determined by the K2 value in the TDRA table row indicated by the TDRA field of the DCI that is transmitted in slot n. If the UL-SCH indicator field is set to ‘0’ , the A-CSI may be mapped on the REs allocated for the PUSCH, and the slot in which the PUSCH is transmitted may be determined by a TDRA field value, m, of the DCI that is transmitted in slot n. The K2 value may be determined as where Yj, j=0, . . ., NRep-1 may be the corresponding entries from the list specified by the higher layer parameter, such as the reportSlotOffsetList IE, in IE CSI-ReportConfig for the NRep triggered CSI reporting settings, and Yj (m+1) may be the (m+1) -th entry of Yj.
[0302] The slot in which the UE may transmit the PUSCH may be determined based on K2 as follows:
[0303] where n is the slot with the scheduling DCI, K2 is based on the PUSCH numerology, and μPUSCH and μPDCCH are the subcarrier spacing configurations for the PUSCH and the PDCCH, respectively.
[0304] Network spatial adaptation may cause antenna port reduction and beam width change, potentially impacting beam failure detection and management. Current 3GPP specifications (R-15 / R-16 / R-17) may lack mechanisms to update related parameters. An efficient mechanism may be needed to enhance beam procedure reliability in these scenarios.
[0305] Specifically, for beam failure recovery procedures, the beam failure detection threshold may have a physical meaning, corresponding to a quality at which the PDCCH BLER is 10%. The occurrence of a beam failure instance during the NES adaptation may indicate that the link between the UE and gNB is unreliable. The network may need an efficient method to enhance the beam failure recovery procedure, which may alleviate the risk of unreliability.
[0306] Additionally, beam management may include a set of procedures to establish and retain an optimal beam pair for good connectivity. A beam pair may include a transmit beam and a corresponding receive beam in one link direction. The beam pairing procedure may be affected by the NES adaptation. Consequently, the network may need necessary enhancements to beam management-related procedures to enable efficient NES adaptation.
[0307] Furthermore, if a (serving) gNB (e.g., associated with one or more serving cell (s) / serving special cell (s) / serving secondary cell (s) ) performs fast spatial adaptation for energy saving purposes, the RRC-configured parameters for beam failure detection RS set (e.g., q_0) and for candidate beam identification RS set (e.g., q_1) may not be able to be updated in time. This delay may result in incorrect detection of beam failure or candidate beams. Therefore, solutions that may reduce the above signaling overhead may be beneficial to consider.
[0308] Enhancement on joint spatial domain and power domain adaptation
[0309] The joint adaptation of the spatial domain and the power domain may require clarification, particularly regarding the priority of power offset between these domains. The network may configure the UE with one or more power offset values (e.g., specified by the powerControlOffset IE or the powerControlOffsetSS IE) in a CSI-RS resource. If the power offset value is configured in the CSI-RS resource configuration, the power offset value may serve as the default and may be used for spatial domain adaptation.
[0310] The powerControlOffset IE or the powerControlOffsetSS IE may also be a parameter in the sub-configuration (s) of a CSI report configuration. The sub-configuration (s) may be used for PD adaptation or joint adaptation of spatial domain and power domain. If none of the powerControlOffset IE and the powerControlOffsetSS IE is configured in the sub-configuration for joint adaptation, the powerControlOffset IE or the powerControlOffsetSS IE from the CSI-RS resource configuration may serve as the default.
[0311] When configured in the sub-configuration for joint adaptation, the powerControlOffset IE or the powerControlOffsetSS IE may override the one in the CSI-RS resource configuration, with higher priority. That is, the priority of the power offset value configured in the sub-configuration may be higher than the priority of the power offset value configured in the CSI-RS resource configuration. The network may configure the UE with a relative power offset value in the sub-configuration by referencing to the power offset value in the CSI-RS resource configuration. Additionally or alternatively, the network may choose a power offset value already configured in the CSI-RS resource configuration. For example, the network may select the power offset value (s) already configured in the CSI-RS resource configuration as the power offset value (s) in the sub-configuration.
[0312] Enhancement on Beam Management
[0313] I. Beam Failure Recovery Procedure
[0314] A beam failure recovery procedure may be enhanced or improved through scaling the threshold after Network Energy Saving (NES) adaptation. This approach may address the challenges that arise when beam failure detection procedures encounter NES scenarios, potentially requiring adjustments to the thresholds for detecting beam failure events.
[0315] For beam failure detection, the BS may configure the UE with beam failure detection reference signals (SSBs or CSI-RSs) , where the BS may include the serving gNB associated with one or more serving cell (s) / serving special cell (s) / serving secondary cell (s) . The UE may declare beam failure when the number of failure instance indications from the physical layer reaches a configured threshold before a timer expires.
[0316] The physical layer may trigger a Beam Failure Instance (BFI) when the RSRP of the reference signal of the serving beam falls below the threshold (e.g., 10%BLER of a hypothetical PDCCH) . When beam failure detection procedures encounter the NES scenarios, the threshold may need to be adjusted. For example, the 10%BLER may increase to 15%as beam power reduces.
[0317] For beam failure recovery on an SpCell (after detecting beam failure on the SpCell) , the UE may trigger a beam failure recovery procedure by initiating an RA procedure (2-step / 4-step, Contention-based / Contention-free) on the PCell. The UE may also select a suitable (DL) beam for beam failure recovery, prioritizing the dedicated RA resources if provided by the BS (e.g., gNB) . If the RA procedure was initiated for SpCell beam failure recovery and the value of a particular IE, spCell-BFR-CBRA, is set to ‘true’ , the UE may include a beam failure indication in a BFR MAC CE.
[0318] Table 1 presents an example of the BeamFailureRecoveryConfig IE using Abstract Syntax Notation One (ASN. 1) . As shown in Table 1, the rsrp-ThresholdSSB IE may serve as the L1-RSRP threshold for assessing whether a candidate beam is suitable for the UE to attempt contention-free random access for beam failure recovery. In the context of power domain network energy saving, the L1-RSRP threshold for candidate beam identification may require adaptation.
[0319] Table 1
[0320] An additional threshold (e.g., specified by an IE termed rsrp-ThresholdSSB_NES) specifically for the NES mode may be introduced. This threshold (e.g., the rsrp-ThresholdSSB_NES IE) may be used to assess whether a candidate beam is suitable for the UE to attempt contention-free random access for beam failure recovery. The UE may use the rsrp-ThresholdSSB_NES IE when, or only when, the NES mode or NES operation is activated or implemented by the serving RAN.
[0321] For a PCell, several methods may be used to scale the threshold (e.g., the L1-RSRP threshold) in response to the NES adaptation. For example, the L1-RSRP threshold may be directly replaced by another threshold (e.g., the rsrp-ThresholdSSB_NES IE) . Additionally or alternatively, the L1-RSRP threshold may be multiplied by a ratio of an updated power offset value and an original power offset value. The powerControlOffset IE or the powerControlOffsetSS IE may also serve as a parameter / power offset value in the sub-configuration (s) of a CSI report configuration. In response to performing the NES adaptation, the network may reconfigure, via RRC signaling, the rsrp-ThresholdSSB IE to inform the UE of the latest threshold for evaluating the candidate beam. Additionally or alternatively, the network may configure the UE with an updated threshold via L1 / L2 signaling.
[0322] Figure 1 is a schematic diagram illustrating a format of a truncated BFR MAC CE, according to an example implementation of the present disclosure. As illustrated in Figure 1, the truncated BFR MAC CE (e.g., MAC CE 100) may include the several fields:
[0323] Ci field (e.g., C1 to C31) : Each Ci filed may indicate whether a beam failure report for a corresponding cell is activated and whether an octet containing the AC field for the SCell with the serving cell index i (e.g., ServCellIndex i) is present in MAC CE 100.
[0324] SP field: This field may include a BFD indication for the SpCell of the MAC entity.
[0325] AC field: This field may indicate the presence of a candidate RS ID for a corresponding cell.
[0326] R field: Each R filed may include a reserved bit for potential future use.
[0327] Candidate RS ID field: This field may be used to specify a candidate RS ID.
[0328] As an example of L2 signaling mentioned above, the network may use a new MAC CE similar to MAC CE 100 to indicate the updated L1-RSRP threshold (e.g., the rsrp-ThresholdSSB IE) to the UE. For example, the new MAC CE may include a field indicating the updated L1-RSRP threshold that is used for a PCell after the NES adaptation.
[0329] In some implementations, the network may configure the UE with multiple candidate thresholds (not including the legacy threshold, such as the rsrp-ThresholdSSB IE) for the NES adaptation. Table 2 presents an example of the BeamFailureRecoveryConfig IE using ASN. 1 notation.
[0330] Table 2
[0331] As shown in Table 2, the network may utilize several IEs within the BeamFailureRecoveryConfig IE to specify the candidate thresholds. For example, the BeamFailureRecoveryConfig IE may include the rsrp-ThresholdSSB-1 IE (specifying a first candidate threshold) , the rsrp-ThresholdSSB-2 IE (specifying a second candidate threshold) , the rsrp-ThresholdSSB-3 IE (specifying a third candidate threshold) , and the rsrp-ThresholdSSB-4 IE (specifying a fourth candidate threshold) .
[0332] After being configured with the candidate thresholds for the PCell, the UE may determine the best beam, based on the DL channel quality, by using one or more L1-RSRP thresholds selected from the candidate thresholds for the PCell.
[0333] It should be noted that while Table 2 shows four candidate thresholds, this is just an example. The number of candidate thresholds is not limited to four. The network may configure more or fewer candidate thresholds as needed.
[0334] For beam failure recovery on an SCell, once a beam failure is detected, the UE may trigger a BFR procedure by transmitting a BFR MAC CE for the SCell. If available, the UE may also select a suitable beam for the SCell and indicate both the selected beam and information about the beam failure in the BFR MAC CE.
[0335] Table 3 presents an example of the BeamFailureRecoveryRSConfig IE using ASN. 1 notation.
[0336] Table 3
[0337] As shown in Table 3, the rsrp-ThresholdBFR-r16 IE within the BeamFailureRecoveryRSConfig IE may specify an L1-RSRP threshold. The UE may use the L1-RSRP threshold to determine whether to include a candidate beam in a BFR MAC CE for the SCell. The network may configure this parameter (e.g. the rsrp-ThresholdBFR-r16 IE) in every instance of this IE (e.g., the BeamFailureRecoveryRSConfig IE) .
[0338] Additionally, for the SCell, several methods may also be used to scale the threshold (e.g., the L1-RSRP threshold) in response to the NES adaptation. For example, the L1-RSRP threshold for the NES adaptation of an SCell may be directly replaced by another threshold. Additionally or alternatively, the L1-RSRP threshold may be multiplied by a ratio of an updated power offset value and an original power offset value. The powerControlOffset IE or the powerControlOffsetSS IE may also serve as a parameter / power offset value in the sub-configuration (s) of a CSI report configuration. In response to performing the NES adaptation, the network may reconfigure, via RRC signaling (e.g., via an RRC reconfiguration message or via an RRC resume messages) , the L1-RSRP threshold (e.g., the rsrp-ThresholdBFR IE) to inform the UE of the latest threshold for evaluating the candidate beam for the serving cell (e.g., the SCell or the special cell) .
[0339] In some implementations, the network may configure the UE with multiple candidate thresholds (not including the legacy threshold, such as the rsrp-ThresholdBFR-r16 IE) for the NES adaptation of an SCell. Table 4 presents an example of the BeamFailureRecoveryRSConfig IE using ASN. 1 notation.
[0340] Table 4
[0341] As shown in Table 4, the network may utilize several IEs within the BeamFailureRecoveryRSConfig IE to specify the candidate thresholds. For example, the BeamFailureRecoveryRSConfig IE may include the rsrp-ThresholdBFR-r16-1 IE (specifying a first candidate threshold) , the rsrp-ThresholdBFR-r16-2 IE (specifying a second candidate threshold) , the rsrp-ThresholdBFR-r16-3 IE (specifying a third candidate threshold) , and the rsrp-ThresholdBFR-r16-4 IE (specifying a fourth candidate threshold) .
[0342] The UE may select, based on the DL channel quality, one of the candidate thresholds as the updated L1-RSRP threshold for the SCell.
[0343] It should be noted that while Table 4 shows four candidate thresholds, this is just an example. The number of candidate thresholds for the SCell is not limited to four. The network may configure more or fewer candidate thresholds as needed.
[0344] In some implementations, a UE may support the functionality for evaluating and reporting, before the NES adaptation, a hypothetical beam failure report and / or a hypothetical RLF report based on one or more hypothetical power offset values indicated or configured by the network.
[0345] The network may transmit a specific DL reference signal to the UE for the hypothetical beam failure / RLF detection. The specific DL reference signal may be transmitted on a resource different from the original DL data channel resource, where the network may use the original DL data channel resource to transmit a DL reference signal to the UE for a regular beam failure / RLF detection.
[0346] Before the NES adaptation, the UE may evaluate multiple candidate beams that may potentially cause the beam failure. The timing of performing the evaluation of the hypothetical beam failure / RLF detection may be periodic or event-triggered. The triggering event may include a NES CSI-RS measurement event that occurs before the NES adaptation. The UE may transmit the hypothesis report (e.g., the hypothetical beam failure report and / or the hypothetical RLF report) to the network before the actual NES adaptation. For example, the UE may transmit the hypothetical report (s) to the network via a MAC CE (e.g., a modified BFR MAC CE or a MAC CE with a new format) , as illustrated in Figure 2.
[0347] Figure 2 is a schematic diagram illustrating a format of a MAC CE that a UE may use to inform a network of a hypothetical beam failure reference ID before an actual NES adaptation, according to an example implementation of the present disclosure.
[0348] As shown in Figure 2, the MAC CE (e.g., MAC CE 200) may include several fields:
[0349] SP field: this field may indicate a hypothetical BFD for the SpCell of the MAC entity. For example, if set to 1, the SP field may indicate that a hypothetical beam failure for the SpCell is detected; otherwise, the SP field may be set to 0.
[0350] Ci field (e.g., C1 to C15 in Figure 2) : Each Ci field may indicate whether a corresponding hypothetical beam failure report is activated and whether an octet containing the AC field for the SCell with the serving cell index i (e.g., ServCellIndex i) is present in MAC CE 200. For example, a Ci field set to 1 may indicate that the hypothetical beam failure report for the SCell with the serving cell index i is activated, the evaluation of the candidate beams according to requirements has been completed, and the octet containing the AC field for the SCell with ServCellIndex is present in MAC CE 200. Conversely, a Ci field set to 0 may indicate that the hypothetical beam failure report for the SCell with ServCellIndex i is either not activated or activated but the evaluation of candidate beams has not been completed, and the octet containing the AC field for the SCell with ServCellIndex i is not present in MAC CE 200. The octet (s) containing the AC field (s) may be present in MAC CE 200 in a specific order (e.g., an ascending order) based on the serving cell indices of the serving cells (e.g., ServCellIndex) .
[0351] AC field: This filed may indicate the presence of a hypothetical beam failure RS ID in the corresponding octet. For example, the AC field may be set to a 1 if at least one SSB indicated in a particular list (e.g., the candidateBeamRSSCellList IE) and corresponding to the SCell with ServCellIndex i has an SS-RSRP value below the L1-RSRP threshold used for hypothetical BFD, or if at least one CSI-RS indicated in the particular list and corresponding to the SCell with ServCellIndex i has a CSI-RSRP value below the L1-RSRP threshold used for BFD. If neither of the above conditions is met, the AC field may be set to 0. When the AC field is set to 1, the hypothetical beam failure RS ID may be present in the corresponding octet. Conversely, when the AC field is set to 0, R bits may be present instead.
[0352] R field: This field may include a reserved bit for future use.
[0353] Hypothetical Beam Failure RS ID field: This field may include a hypothetical beam failure RS ID (e.g., the index of an SSB or CSI-RS) . For example, the index included in the Hypothetical Beam Failure RS ID field may indicate an SSB, among the SSBs in the candidateBeamRSSCellList IE, with an SS-RSRP value less than, or equal to, the L1-RSRP threshold used for the BFD, or may correspond to a CSI-RS, among the CSI-RSs in the candidateBeamRSSCellList IE, with a CSI-RSRP value less than, or equal to, the L1-RSRP threshold used for the BFD. The index of the SSB or CSI-RS may correspond to the position of the entry that corresponds to the SSB or CSI-RS in the particular list (e.g., the candidateBeamRSSCellList IE) . For example, index 0 may correspond to the first entry in the candidateBeamRSSCellList IE, index 1 may correspond to the second entry, and so on.
[0354] If the PUSCH cannot accommodate the full MAC CE (e.g., MAC CE 200) , a truncated version may be used. In this case, only the index of the SSB with the best SS-RSRP value less than, or equal to, the L1-RSRP threshold or the index of the CSI-RS with the best CSI-RSRP value less than, or equal to, the L1-RSRP threshold may be included in the MAC CE.
[0355] The particular list (e.g., the candidateBeamRSSCellList IE) may include the indices of the CSI-RSs and / or SSBs. For example, the index of a CSI-RS included in the list may have a CSI-RSRP value that is larger than a particular threshold, such as the rsrp-ThresholdBFR IE. The index of a specific CSI-RS or SSB may correspond to the index of a specific entry in the list. For example, the index 0 may correspond to the first entry in the list, the index 1 may correspond to the second entry in the list, and so on.
[0356] Table 5 presents an example of the mapping between the actual (CSI-RS / SSB) indices and the reported (CSI-RS / SSB) indices, where the reported index may refer to the index of the entry in the list (e.g., the rsrp-ThresholdBFR IE) .
[0357] Table 5
[0358] As shown in Table 5, the first row may indicate the actual indices, and the second row may indicate the corresponding reported indices. The reported indices in Table 5 may be identical to the candidate beam indices in the candidateBeamRSSCellList IE. Table 5 illustrates how each reported index may be mapped to a specific actual index of a CSI-RS / SSB. For example, among the candidate beam indices in the candidateBeamRSSCellList IE, if the reported index is 3, then based on Table 5, the corresponding actual index may be 11.
[0359] The NES adaptation may lead to changes / updates in the indexing in the list (e.g., the candidateBeamRSSCellList IE) . Taking Table 5 as an example, after applying the NES adaptation, certain reported indices, such as 2 (corresponding to the actual index 10) , 4 (corresponding to the actual index 12) , and 5 (corresponding to the actual index 13) , may be removed from the list. The UE, however, may not be aware of these updates to the list before an RRC reconfiguration occurs.
[0360] Specifically, after the NES adaptation, the reported indices in the list (e.g., the candidateBeamRSSCellList IE) may undergo rearrangement. For example, as shown in Table 6, the new range of the reported indices may span from 0 to 5. This rearrangement may lead to changes in the mapping relationship between the reported indices and the actual indices. For example, after the NES adaptation, the reported index 2 may correspond to the actual index 11, whereas before the NES adaptation, the reported index 3 may corresponded to the actual index 11. Such misalignments may potentially lead to beam failures. Given that RRC reconfiguration may not be sufficiently time-efficient for these updates, L1 / L2 signaling may be employed to promptly inform the UE of the latest changes.
[0361] Table 6
[0362] To address this issue, in some implementations, the network may broadcast the updated mapping information (e.g., as shown in Table 6) as part of the system information. The UE may then use the updated mapping information to update the mapping relationship between the actual and reported indices.
[0363] Additionally or alternatively, the CSI-RS index may be expanded to include a sub-configuration ID and / or a pattern ID. Such an expansion will be discussed in detail below with reference to Tables 7 and 8.
[0364] Table 7
[0365] Table 8
[0366] Table 7 presents an example of the mapping relationship between the actual indices and reported indices. For example, the reported index 0 may be mapped to the actual index 4, the reported index 1 may be mapped to the actual index 5, and the reported index 2 may be mapped to the actual index 10.
[0367] Table 8 presents an example of an expanded version of the mapping relationship described in Table 7. As shown in Table 8, the reported index 0 may be mapped to the actual index 4 with the sub-configuration ID 1 (denoted as “4-1” in Table 8) , the reported index 1 may be mapped to the actual index 4 with the sub-configuration ID 2 (denoted as “4-2” in Table 8) , and the reported index 2 may be mapped to the actual index 4 with the sub-configuration ID 3 (denoted as “4-3” in Table 8) , the reported index 3 may be mapped to the actual index 5 with the sub-configuration ID 1 (denoted as “5-1”in Table 8) , the reported index 4 may be mapped to the actual index 5 with the sub-configuration ID 2 (denoted as “5-2” in Table 8) , the reported index 5 may be mapped to the actual index 10 with the sub-configuration ID 1 (denoted as “10-1” in Table 8) , the reported index 6 may be mapped to the actual index 10 with the sub-configuration ID 2 (denoted as “10-2” in Table 8) , the reported index 7 may be mapped to the actual index 10 with the sub-configuration ID 3 (denoted as “10-3” in Table 8) , and the reported index 8 may be mapped to the actual index 10 with the sub-configuration ID 4 (denoted as 10-4 in Table 8) . After the NES adaptation, the mapping information (e.g., as shown in Table 8) may maintain the same index values as before the NES adaptation.
[0368] A BFR MAC CE provided by the UE may not trigger an SR procedure and / or a random access procedure when the serving cell is in a Cell DTX / Cell DRX inactive period. When the serving cell is in a Cell DTX / Cell DRX active period, the BFR MAC CE provided by the UE may trigger an SR procedure (e.g., includes transmitting an SR on a PUCCH) and / or a random access procedure (only) . The UE may be configured by the serving RAN to enable or disable the transmission of the BFR MAC CE during the Cell DTX / Cell DRX inactive period. That is, the serving RAN may allow or not allow the UE to transmit the BFR MAC CE during the Cell DTX / Cell DRX inactive period.
[0369] II. Beam Management Procedure
[0370] In some implementations, a UE may support a feature that is related to RX beam selection using the CSI-RS resource repetition. For example, for an RX beam switching procedure, it may be performed with a repetition-related parameter (e.g., the CSI-RS resource repetition) set to “ON. ” Furthermore, the UE may indicate to the network a recommended CSI-RS resource repetition number per resource set.
[0371] The feature described above may be mandatory for the UE capability, at least for FR2. The possible number of CSI-RS resource repetitions may be selected from a candidate value set of {2, 3, 4, 5, 6, 7, 8} . As the power of the beam may be reduced when the NES adaptation is applied, the UE may need more repetition times to tune the suitable RX beam. For example, the possible number of CSI-RS resource repetitions may be larger than 8.
[0372] Figure 3 is a schematic diagram illustrating a time restriction for channel measurements, according to an example implementation of the present disclosure. As illustrated in Figure 3, if a UE is not configured with a time restriction for channel measurements, the UE may derive the channel measurement result (e.g., the computed CSI value) to be reported in the uplink slot (s) based on only the (NZP) CSI-RSs that occur no later than the occasion of the CSI reference resource (e.g., CSI Ref 302) associated with the CSI resource setting. That is, the UE may use only the CSI-RSs that fall within time window 304 for channel measurements if the UE is not configure with the time restriction for channel measurements. Conversely, if the UE is configured with a time restriction for channel measurements, the UE may derive the channel measurement result (e.g., the computed CSI value) to be reported in the uplink slot (s) based on only the most recent (NZP) CSI-RS that occurs no later than the occasion of the CSI reference resource (e.g., CSI Ref 302) associated with the CSI resource setting. For example, the UE may use only the CSI-RS (s) (e.g., CSI Ref 302) that fall within time window 306 for channel measurements if the UE is configure with a time restriction for channel measurements. After the NES adaptation, the timing of the time restriction may be updated.
[0373] In some implementations, a NES CSI-RS pilot (which may be referred to as NES CSI reference resource) , for indicating the timing of when NES adaptation may be used. Figure 4 is a schematic diagram illustrating a time restriction for channel measurements, according to an example implementation of the present disclosure. As illustrated in Figure 4, if a UE is not configured with a time restriction for channel measurements, the UE may derive the channel measurement result (e.g., the computed CSI value) to be reported in the uplink slot (s) based on only the NZP CSI-RSs that occur later than the occasion of the NES CSI reference resource (e.g., NES CSI Ref 402) but no later than the occasion of the CSI reference resource (e.g., CSI Ref 404) . In other words, the UE may use for channel measurements only those CSI-RSs that fall within time window 406 between the occasion of NES CSI Ref 402 and the occasion of CSI Ref 404.
[0374] Figure 5 is a schematic diagram illustrating a time restriction for channel measurements, according to an example implementation of the present disclosure. As illustrated in Figure 5, if a UE is configured with a time restriction for channel measurements, the UE may derive the channel measurement result (e.g., the computed CSI value) to be reported in the uplink slot (s) based on only the most recent NZP CSI-RS that occurs later than occasion of the CSI reference resource (e.g., CSI Ref 502) but no later than the NES CSI reference resource (e.g., NES CSI Ref 504) . In Figure 5, there may be no valid CSI-RSs between the occasion of CSI Ref 502 and the occasion of NES CSI Ref 504. In this scenario, there may be no valid CSI-RS (or CSI value) to be reported and the reporting procedure may be postponed.
[0375] Fast adaptation mechanisms may be used for a link recovery procedure, involving the use of the beam failure detection RS set (q_0) and the candidate beam identification RS set (q_1) .
[0376] In some implementations, a UE may be configured, for each (DL) BWP of a serving cell, with a set q_0 of periodic CSI-RS resource configuration indices provided by the failureDetectionResourcesToAddModList IE, and a set q_1 of periodic CSI-RS resource configuration indices and / or SS / PBCH block indices provided by the candidateBeamRSList IE, the candidateBeamRSListExt IE, or the candidateBeamRSSCellList IE for the radio link quality measurements on the BWP of the serving cell.
[0377] In some implementations, instead of being configured with the sets q_0 and q_1, for each (DL) BWP of a serving cell, the UE may be configured with two sets, q_0, 0 and q_0, 1, of periodic CSI-RS resource configuration indices by the failureDetectionSet1 IE and the failureDetectionSet2 IE, respectively, which may be activated by a MAC CE. Correspondingly, the UE may also be configured with two sets, q_1, 0 and q_1, 1, of the periodic CSI-RS resource configuration indices and / or SS / PBCH block indices by the candidateBeamRS-List IE and the candidateBeamRS-List2 IE, respectively, for radio link quality measurements on the (DL) BWP of the serving cell. The set q_0, 0 may be associated with the set q_1, 0, and the set q_0, 1 may be associated with the set q_1, 1.
[0378] When a serving BS (e.g., a gNB associated with one or more serving special cells or secondary cells) performs the fast spatial adaptation for energy saving purposes, the RRC-configured sets q_0 and q_1 may not update quickly enough. This delay may result in incorrect detection of beam failure or candidate beams. To address this issue, in some implementations, multiple detection sets and candidate beam RS lists (e.g., more than two lists) may be used for the NES applications requiring fast adaptation. The network may activate or deactivate the configured beam failure detection resources of a serving cell by transmitting an enhanced BFD RS indication MAC CE.
[0379] Figure 6 is a schematic diagram illustrating a format of an enhanced BFD RS indication MAC CE, according to an example implementation of the present disclosure. As illustrated in Figure 6, the enhanced BFD RS indication MAC CE (e.g., MAC CE 600) may include multiple octets (Oct 1 to Oct 2N-1) and fields for Serving Cell ID, DL BWP ID, and BFD RS IDs for N different candidate sets (e.g., Set 1 to Set N) . The N candidate sets may be specified by a series IEs, starting from the failureDetectionSet1 IE for the first set, the failureDetectionSet2 IE for the second set, and continuing up to the failureDetectionSetN IE for the Nth set, where N is a positive integer.
[0380] The first octet (Oct 1) of MAC CE 600 may include a reserved (R) bit, a Serving Cell ID, and a DL BWP ID. The subsequent octets of MAC CE 600 may include information for Set 1 to Set N, each with two BFD RS IDs (e.g., BFR RS ID0 and BFR RS ID1) . Each of these octets may start with an R bit, followed by an S bit, and then the BFD-RS ID. The BFD RS IDi (where i may be 1 or 2) for each set may indicate the BFD RS resource from a specific BFD RS set (e.g., one of Set 1 to Set N) . The S bit may indicate whether a specific BFD RS ID (e.g., BFD RS ID1) for the corresponding set is present in the MAC CE 600. For example, when the S bit in Oct 2 is set to 0, it may indicate that BFD RS ID1 in Set 1 is not presented. When the S bit in Oct 2 is set to 1, it may indicate that BFD RS ID1 in Set 1 is present.
[0381] In some implementations, a mechanism may be introduced to enable fast switching or updating of the set q_0 and / or the set q_1. Specifically, this mechanism may allow the adaptation to the spatial adjustments of the gNB using group common DCI and group-specific multiple fields for multiple UEs.
[0382] Figure 7 is a flowchart illustrating method / process 700 for BFR enhancement, according to an example implementation of the present disclosure. Although actions 702 and 704 are illustrated, as separate actions, represented as independent blocks in Figure 7, these separately illustrated actions should not be construed as to be necessarily order-dependent. The order in which the actions are performed in Figure 7 is not intended to be construed as a limitation, and any number of the disclosed blocks may be combined in any order to implement the method, or an alternative method. Each of actions 702 and 704 may be performed independent of the other actions, and may be omitted in some implementations of the present disclosure. Moreover, method / process 700 may be combined with other procedures / methods described in the present disclosure. Method / process 700 may be performed by a UE, with each action of process 700 corresponding to an operation executed by the UE.
[0383] In action 702, process 700 may start by receiving, from a BS, an indication of whether a NES operation is activated or deactivated by the BS. In action 704, process 700 may then perform a BFR procedure after receiving the indication. The BFR procedure will be discussed in detail below with reference to Figure 8. After performing the BFR procedure, process 700 may then end.
[0384] Figure 8 is a flowchart illustrating method / process 800 for BFR enhancement, according to an example implementation of the present disclosure. Method / process 800 may correspond to the BFR procedure described in action 704 of Figure 7. Although actions 802, 804, and 806 are illustrated, as separate actions, represented as independent blocks in Figure 8, these separately illustrated actions should not be construed as to be necessarily order-dependent. The order in which the actions are performed in Figure 8 is not intended to be construed as a limitation, and any number of the disclosed blocks may be combined in any order to implement the method, or an alternative method. Each of actions 802, 804, and 806 may be performed independent of the other actions, and may be omitted in some implementations of the present disclosure. Moreover, method / process 800 may be combined with other procedures / methods described in the present disclosure. Method / process 800 may be performed by a UE, with each action of process 800 corresponding to an operation executed by the UE.
[0385] In action 802, process 800 may start by, determining whether the indication indicates that the NES operation is activated.
[0386] If the indication indicates that the NES operation is activated, in action 804, process 800 may then apply a first threshold to select a first beam for the BFR procedure. For example, the UE may select, based on the first threshold, the first beam from a first list that is specifically configured for the NES operation. In some implementations, the UE may receive, from the BS, the first list via one of a broadcast message, a MAC CE, and a DCI format.
[0387] Conversely, if the indication does not indicate that the NES operation is activated (e.g., the indication indicates that the NES operation is deactivated) , in action 806, process 800 may then apply a second threshold that is separated from the first threshold to select a second beam for the BFR procedure. For example, the UE may select, based on the second threshold, the second beam from a second list that is not specifically configured for the NES operation. After performing action 804 or 806, process 800 may then end.
[0388] In some implementations, the UE may determine the first threshold by multiplying the second threshold by a predetermined factor.
[0389] In some implementations, the UE may receive, from the BS, a CSI report configuration (e.g., the CSI-ReportConfig IE) including a first power offset value and a second power offset value. The predetermined factor may be a ratio of the first power offset value and the second power offset value. In some implementations, the first power offset value may be specified by one of the powerControlOffset IE and the powerControlOffsetSS IE, and the second power offset value may be specified by the other one of the powerControlOffset IE and the powerControlOffsetSS IE. In some implementations, the UE may receive, from the BS, the first threshold via one of an RRC message, a MAC CE, and a DCI format.
[0390] According to Figures 7 and 8, a UE may adapt the BFR procedure based on the activation status of the NES operation. The approach may address challenges (e.g., antenna port reduction and / or beam width changes) arising from network spatial adaptation during the NES operation.
[0391] To accommodate the network changes and maintain effective beam management, the UE may employ different beam selection strategies depending on the NES operation status. For example, when the NES operation is activated, the UE may apply a first threshold to select a beam from a list configured specifically for the NES operation. The first threshold may be more suitable for energy-saving conditions. Conversely, when the NES operation is deactivated, the UE may apply a second threshold to select a beam from a standard list.
[0392] By utilizing different thresholds (e.g., L1-RSRP thresholds) for different operational states, this adaptive BFR procedure may offer an efficient method for beam management in network energy-saving scenarios. Consequently, the approach may enhance connection reliability while simultaneously supporting the networks energy optimization efforts.
[0393] It should be noted that in the present disclosure, the BS may perform methods / actions corresponding to those performed by the UE. For example, the receiving actions performed by the UE may correspond to the transmitting / configuring actions of the BS; the transmitting actions performed by the UE may correspond to the receiving actions of the BS. That is, the BS and the UE may have reciprocally aligned roles in transmission and reception.
[0394] For example, when considering process 700 and / or process 800 from the perspective of the BS, the actions may be described as follows: the BS may transmit, to a UE, a first threshold and a second threshold. The first threshold and the second threshold may be separated parameters configured for a BFR procedure. The BS may also transmit, to the UE, an indication of whether a NES operation is activated or deactivated by the BS, thereby enabling the UE to apply the first threshold to select a first beam for the BFR procedure in response to the indication indicating that the NES operation is activated, and further enabling the UE to apply the second threshold to select a second beam for the BFR procedure in response to the indication indicating that the NES operation is deactivated.
[0395] In some implementations, the BS may transmit, to the UE, a first list that is specifically configured for the NES operation via various signaling, such as one of a broadcast message, a MAC CE, and a DCI format, thereby enabling the UE to select, based on the first threshold, the first beam from the first list in a case that the indication indicates that the NES operation is activated.
[0396] In some implementations, the BS may transmit, to the UE, a second list that is not specifically configured for the NES operation, thereby enabling the UE to select, based on the second threshold, the second beam from the second list in a case that the indication indicates that the NES operation is deactivated.
[0397] In some implementations, the BS may transmit, to the UE, the first threshold via one of an RRC message, a MAC CE, and a DCI format.
[0398] Figure 9 is a block diagram illustrating node 900 for wireless communications, in accordance with various aspects of the present disclosure. As illustrated in Figure 9, node 900 may include transceiver 920, processor 928, memory 934, one or more presentation components 938, and at least one antenna 936. Node 900 may also include a radio frequency (RF) spectrum band module, a BS communications module, a network communications module, and a system communications management module, Input / Output (I / O) ports, I / O components, and a power supply (not illustrated in Figure 9) .
[0399] Each of the components may directly or indirectly communicate with each other over one or more buses 940. Node 900 may be a UE or a BS that performs various functions disclosed with reference to Figures 1 through 8.
[0400] Transceiver 920 has transmitter 922 (e.g., transmitting / transmission circuitry) and receiver 924 (e.g., receiving / reception circuitry) and may be configured to transmit and / or receive time and / or frequency resource partitioning information. Transceiver 920 may be configured to transmit in different types of subframes and slots including, but not limited to, usable, non-usable, and flexibly usable subframes and slot formats. Transceiver 920 may be configured to receive data and control channels.
[0401] Node 900 may include a variety of computer-readable media. Computer-readable media may be any available media that may be accessed by node 900 and include volatile (and / or non-volatile) media and removable (and / or non-removable) media.
[0402] The computer-readable media may include computer-storage media and communication media. Computer-storage media may include both volatile (and / or non-volatile media) , and removable (and / or non-removable) media implemented in any method or technology for storage of information such as computer-readable instructions, data structures, program modules, or data.
[0403] Computer-storage media may include RAM, ROM, EPROM, EEPROM, flash memory (or other memory technology) , CD-ROM, Digital Versatile Disks (DVD) (or other optical disk storage) , magnetic cassettes, magnetic tape, magnetic disk storage (or other magnetic storage devices) , etc. Computer-storage media may not include a propagated data signal. Communication media may typically embody computer-readable instructions, data structures, program modules, or other data in a modulated data signal, such as a carrier wave, or other transport mechanisms and include any information delivery media.
[0404] The term “modulated data signal” may imply a signal that has one or more of its characteristics set or changed in such a manner as to encode information in the signal. Communication media may include wired media, such as a wired network or direct-wired connection, and wireless media, such as acoustic, RF, infrared, and other wireless media. Combinations of any of the above-listed components should also be included within the scope of computer-readable media.
[0405] Memory 934 may include computer-storage media in the form of volatile and / or non-volatile memory. Memory 934 may be removable, non-removable, or a combination thereof. Example memory may include solid-state memory, hard drives, optical-disc drives, etc. As illustrated in Figure 9, memory 934 may store a computer-readable and / or computer-executable instructions 932 (e.g., software codes) that are configured to, when executed, cause processor 928 to perform various functions disclosed herein, for example, with reference to Figures 1 through 2. Alternatively, instructions 932 may not be directly executable by processor 928 but may be configured to cause node 900 (e.g., when compiled and executed) to perform various functions disclosed herein.
[0406] Processor 928 (e.g., having processing circuitry) may include an intelligent hardware device, e.g., a Central Processing Unit (CPU) , a microcontroller, an ASIC, etc. Processor 928 may include memory. Processor 928 may process data 930 and instructions 932 received from memory 934, and information transmitted and received via transceiver 920, the baseband communications module, and / or the network communications module. Processor 928 may also process information to send to transceiver 920 for transmission via antenna 936 to the network communications module for transmission to a CN.
[0407] One or more presentation components 938 may present data indications to a person or another device. Examples of presentation components 938 may include a display device, a speaker, a printing component, a vibrating component, etc.
[0408] In view of the present disclosure, it is obvious that various techniques may be used for implementing the disclosed concepts without departing from the scope of those concepts. Moreover, while the concepts have been disclosed with specific reference to certain implementations, a person of ordinary skill in the art may recognize that changes may be made in form and detail without departing from the scope of those concepts. As such, the disclosed implementations are to be considered in all respects as illustrative and not restrictive. It should also be understood that the present disclosure is not limited to the particular implementations disclosed and many rearrangements, modifications, and substitutions are possible without departing from the scope of the present disclosure.
Claims
1.A method performed by a User Equipment (UE) for Beam Failure Recovery (BFR) enhancement, the method comprising:receiving, from a Base Station (BS) , an indication of whether a Network Energy Saving (NES) operation is activated or deactivated by the BS; andperforming a BFR procedure after receiving the indication, wherein performing the BFR procedure comprises:in response to the indication indicating that the NES operation is activated, applying a first threshold to select a first beam for the BFR procedure; andin response to the indication indicating that the NES operation is deactivated, applying a second threshold that is separated from the first threshold to select a second beam for the BFR procedure.2.The method of claim 1, wherein applying the first threshold to select the first beam comprises:selecting, based on the first threshold, the first beam from a first list that is specifically configured for the NES operation.3.The method of claim 2, further comprising:receiving, from the BS, the first list via one of a broadcast message, a Medium Access Control (MAC) Control Element (CE) , and a Downlink Control Information (DCI) format.4.The method of claim 1, wherein applying the second threshold to select the second beam comprises:selecting, based on the second threshold, the second beam from a second list that is not specifically configured for the NES operation.5.The method of claim 1, further comprising:determining the first threshold by multiplying the second threshold by a predetermined factor.6.The method of claim 1, further comprising:receiving, from the BS, a Channel State Information (CSI) report configuration comprising a first power offset value and a second power offset value,wherein the predetermined factor is a ratio of the first power offset value and the second power offset value.7.The method of claim 1, further comprising:receiving, from the BS, the first threshold via one of a Radio Resource Control (RRC) message, a Medium Access Control (MAC) Control Element (CE) , and a Downlink Control Information (DCI) format.8.A User Equipment (UE) for Beam Failure Recovery (BFR) enhancement, the UE comprising:at least one processor; andat least one non-transitory computer-readable medium coupled to the at least one processor and storing one or more computer-executable instructions that, when executed by the at least one processor, cause the UE to:receive, from a Base Station (BS) , an indication of whether a Network Energy Saving (NES) operation is activated or deactivated by the BS; andperform a BFR procedure after receiving the indication, wherein performing the BFR procedure comprises:in response to the indication indicating that the NES operation is activated, applying a first threshold to select a first beam for the BFR procedure; andin response to the indication indicating that the NES operation is deactivated, applying a second threshold that is separated from the first threshold to select a second beam for the BFR procedure.9.The UE of claim 8, wherein applying the first threshold to select the first beam comprises:selecting, based on the first threshold, the first beam from a first list that is specifically configured for the NES operation.10.The UE of claim 7, wherein the one or more computer-executable instructions, when executed by the at least one processor, further cause the UE to:receive, from the BS, the first list via one of a broadcast message, a Medium Access Control (MAC) Control Element (CE) , and a Downlink Control Information (DCI) format.11.The UE of claim 8, wherein applying the second threshold to select the second beam comprises:selecting, based on the second threshold, the second beam from a second list that is not specifically configured for the NES operation.12.The UE of claim 8, wherein the one or more computer-executable instructions, when executed by the at least one processor, further cause the UE to:determine the first threshold by multiplying the second threshold by a predetermined factor.13.The UE of claim 12, wherein the one or more computer-executable instructions, when executed by the at least one processor, further cause the UE to:receive, from the BS, a Channel State Information (CSI) report configuration comprising a first power offset value and a second power offset value,wherein the predetermined factor is a ratio of the first power offset value and the second power offset value.14.The UE of claim 8, wherein the one or more computer-executable instructions, when executed by the at least one processor, further cause the UE to:receive, from the BS, the first threshold via one of a Radio Resource Control (RRC) message, a Medium Access Control (MAC) Control Element (CE) , and a Downlink Control Information (DCI) format.15.A Base Station (BS) for Beam Failure Recovery (BFR) enhancement, the BS comprising:at least one processor; andat least one non-transitory computer-readable medium coupled to the at least one processor and storing one or more computer-executable instructions that, when executed by the at least one processor, cause the BS to:transmit, to a User Equipment (UE) , a first threshold and a second threshold, wherein the first threshold and the second threshold are separated parameters configured for a BFR procedure;transmit, to the UE, an indication of whether a Network Energy Saving (NES) operation is activated or deactivated by the BS, thereby enabling the UE to:apply the first threshold to select a first beam for the BFR procedure in response to the indication indicating that the NES operation is activated; andapply the second threshold to select a second beam for the BFR procedure in response to the indication indicating that the NES operation is deactivated.16.The BS of claim 15, wherein the one or more computer-executable instructions, when executed by the at least one processor, further cause the BS to:transmit, to the UE, a first list that is specifically configured for the NES operation via one of a broadcast message, a Medium Access Control (MAC) Control Element (CE) , and a Downlink Control Information (DCI) format, thereby enabling the UE to select, based on the first threshold, the first beam from the first list in a case that the indication indicates that the NES operation is activated.17.The BS of claim 15, wherein the one or more computer-executable instructions, when executed by the at least one processor, further cause the BS to:transmit, to the UE, a second list that is not specifically configured for the NES operation, thereby enabling the UE to select, based on the second threshold, the second beam from the second list in a case that the indication indicates that the NES operation is deactivated.18.The BS of claim 15, wherein the one or more computer-executable instructions, when executed by the at least one processor, further cause the BS to:transmit, to the UE, the first threshold via one of a Radio Resource Control (RRC) message, a Medium Access Control (MAC) Control Element (CE) , and a Downlink Control Information (DCI) format.
Citation Information
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