Apparatus and method for beam failure detection mechanism of enhanced PDCCH with multiple transmissions

Abstract

An apparatus and method for a beam failure detection mechanism for an enhanced PDCCH with multiple transmissions is disclosed. The apparatus includes: a processor that determines a beam failure detection resource combination or a beam failure detection resource for detecting beam failures of multiple transmissions of a physical downlink control channel (PDCCH) for downlink control information (DCI), wherein the beam failure detection resource combination includes multiple beam failure detection resources; and a receiver that receives a signal from at least one of the beam failure detection resources; wherein the processor further determines link quality based on a measurement of a signal received from at least one of the beam failure detection resources, and determines a threshold based on an assumed PDCCH with multiple transmissions using one or more transmission configuration indication (TCI) states; the processor further generates a beam failure assessment report based on the link quality and the threshold.

Description

Technical Field

[0001] The subject matter disclosed herein relates generally to wireless communications and, more particularly, but not limited to, apparatus and methods for a beam failure detection mechanism for an enhanced Physical Downlink Control Channel (PDCCH) with multiple transmissions. Background Art

[0002] The following abbreviations and acronyms are defined herein, at least some of which are referred to in the specification:

[0003] 3rd Generation Partnership Project (3GPP), 5th Generation (5G), New Radio (NR), 5G Node B / Generalized Node B (gNB), Long Term Evolution (LTE), LTE-Advanced (LTE-A), E-UTRAN Node B / Evolved Node B (eNB), Universal Mobile Telecommunications System (UMTS), Worldwide Interoperability for Microwave Access (WiMAX), Evolved UMTS Terrestrial Radio Access Network (E-UTRAN), Wireless Local Area Network (WLAN), Orthogonal Frequency Division Multiplexing (OFDM), Single Carrier Frequency Division Multiple Access (SC-FDMA), Downlink (DL), Uplink (UL), User Entity / Equipment (UE), Network Equipment (NE), Radio Access Technology (RAT), Receive or Receiver (RX), Transmit or Transmitter (TX), Physical Downlink Control Channel (PDCCH), Physical Broadcast Channel (PBCH), Block Error Rate (BLER), Bandwidth Part (BWP), Control Channel Element (CCE), Control Element (CE), control resource set (CORESET), cyclic prefix (CP), channel state information (CSI), channel state information reference signal (CSI-RS), downlink control information (DCI), discontinuous reception (DRX), frequency division multiple access (FDMA), identification (ID), information element (IE), medium access control (MAC), primary cell (PCell), resource element (RE), resource element group (REG), remaining minimum system information (RMSI), radio resource control (RRC), reference signal (RS), secondary cell (SCell), subcarrier spacing (SCS), synchronization signal block (SSB), secondary synchronization signal (SSS), transmit reception point (TRP), frequency range 1 (FR1), frequency range 2 (FR2), synchronization signal (SS), transmission configuration indication (TCI), technical specification (TS), quasi co-location (QCL), primary and secondary cell (PSCell), in-sync / out-of-sync (IS / OOS).

[0004] In wireless communications such as the 3rd Generation Partnership Project (3GPP) mobile network, the wireless mobile network can provide seamless wireless communication services to wireless communication terminals with mobility, i.e., user equipment (UE). The wireless mobile network can be formed by a plurality of base stations and the base stations can perform wireless communications with the UE.

[0005] 5G New Radio (NR) is the latest in the 3GPP family of standards and supports very high data rates with lower latency compared to its predecessor LTE (4G) technology. Two types of frequency ranges (FR) are defined in 3GPP. Frequencies below the 6GHz range (from 450 to 6000MHz) are called FR1, and the millimeter wave range (from 24.25GHz to 52.6GHz) is called FR2. 5G NR supports both FR1 and FR2 frequency bands.

[0006] Enhancements to multi-TRP / panel transmission are studied, which include improved reliability and stability in the case of ideal and non-ideal backhaul between these TRPs (Transmit Receive Points). A TRP is a device that transmits and receives signals and is controlled by the gNB through the backhaul between the gNB and the TRP. A TRP may also be referred to as a transmit-receive identity, or simply an identity.

[0007] In current NR systems, the Physical Downlink Control Channel (PDCCH) is sent from a single TRP. With multiple TRPs, the time-frequency resources used for PDCCH transmission may come from multiple TRPs. Spatial diversity may be utilized in addition to time-frequency diversity. The Enhanced Physical Downlink Control Channel (EPDCCH) allows the utilization of additional resources to improve the reliability and robustness of PDCCH transmissions. Multiple transmissions of E-PDCCH can be sent from the same TRP or from a number of different TRPs. Summary of the invention

[0008] Apparatus and methods for a beam failure detection mechanism for an enhanced PDCCH with multiple transmissions are disclosed.

[0009] According to a first aspect, a device is provided, comprising: a processor, which determines a beam failure detection resource combination or a beam failure detection resource for detecting a beam failure of multiple transmissions of a physical downlink control channel (PDCCH) for downlink control information (DCI), wherein the beam failure detection resource combination comprises multiple beam failure detection resources; and a receiver, which receives a signal from at least one of the beam failure detection resources; wherein the processor further determines the link quality based on a measurement of a signal received from at least one of the beam failure detection resources, and determines a threshold based on an assumed PDCCH having multiple transmissions indicating a TCI state using one or more transmission configurations; and the processor further generates a beam failure assessment report based on the link quality and the threshold.

[0010] According to a second aspect, a device is provided, comprising: a transmitter, which sends a signal on a beam failure detection resource combination or a beam failure detection resource for detecting a beam failure of multiple transmissions of a physical downlink control channel PDCCH for downlink control information DCI, wherein the beam failure detection resource combination comprises multiple beam failure detection resources; and a receiver, which receives a beam failure report generated based on link quality and a threshold, wherein the link quality is determined based on a measurement of signals received from the multiple beam failure detection resources, and the threshold is determined based on a hypothetical PDCCH with multiple transmissions.

[0011] According to a third aspect, a method is provided, comprising: determining, by a processor, a beam failure detection resource combination or a beam failure detection resource for detecting beam failures of multiple transmissions of a physical downlink control channel (PDCCH) for downlink control information (DCI), wherein the beam failure detection resource combination comprises multiple beam failure detection resources; and receiving, by a receiver, a signal from at least one of the beam failure detection resources; wherein the processor further determines link quality based on measurements of signals received from at least one of the beam failure detection resources, and determines a threshold based on an assumed PDCCH with multiple transmissions using one or more transmission configuration indication (TCI) states; and the processor further generates a beam failure assessment report based on the link quality and the threshold.

[0012] According to a fourth aspect, a method is provided, comprising: sending a signal by a transmitter on a beam failure detection resource combination or a beam failure detection resource for detecting a beam failure of multiple transmissions of a physical downlink control channel (PDCCH) for downlink control information (DCI), wherein the beam failure detection resource combination comprises multiple beam failure detection resources; and receiving a beam failure report generated based on link quality and a threshold by a receiver, wherein the link quality is determined based on a measurement of signals received from the multiple beam failure detection resources, and the threshold is determined based on a hypothetical PDCCH with multiple transmissions. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] A more specific description of the embodiments is provided below with reference to specific embodiments shown in the accompanying drawings. Given that these drawings depict only some embodiments and are therefore not to be considered limiting in scope, these embodiments are described and explained below with additional specificity and detail through the use of the accompanying drawings, in which:

[0014] Figure 1 is a schematic diagram illustrating a wireless communication system according to some embodiments of the present disclosure;

[0015] Figure 2 is a schematic block diagram illustrating components of a user equipment (UE) according to some embodiments of the present disclosure;

[0016] Figure 3 is a schematic block diagram illustrating components of a network equipment (NE) according to some embodiments of the present disclosure;

[0017] Figure 4A and 4B is a schematic diagram illustrating an exemplary system for multiple transmissions of a PDCCH for a DCI using multiple TRPs according to some embodiments of the present disclosure;

[0018] Figure 5 is a flow chart illustrating steps of a beam failure detection mechanism for an enhanced PDCCH with multiple transmissions by a UE according to some embodiments of the present disclosure; and

[0019] Figure 6 is a flow chart illustrating the steps of a beam failure detection mechanism for an enhanced PDCCH with multiple transmissions by a NE according to some embodiments of the present disclosure. DETAILED DESCRIPTION

[0020] As will be appreciated by those skilled in the art, multiple aspects of the embodiments may be embodied as systems, devices, methods or program products. Therefore, the embodiments may take the form of full hardware embodiments, full software embodiments (including firmware, resident software, microcode, etc.) or embodiments combining software and hardware aspects.

[0021] Furthermore, one or more embodiments may take the form of a program product embodied in one or more computer-readable storage devices storing machine-readable code, computer-readable code, and / or program code, hereinafter referred to as “code.” The storage devices may be tangible, non-transitory, and / or non-transmitting.

[0022] References in this specification to "one embodiment", "an embodiment", "an example", "some embodiments", "some examples", or similar language mean that a particular feature, structure, or characteristic is included in at least one embodiment or example. Therefore, instances of the phrases "in one embodiment", "in an example", "in some embodiments", and similar language throughout the specification may, but not necessarily, all refer to the same embodiment. It may or may not include all disclosed embodiments. Unless expressly specified otherwise, features, structures, elements, or characteristics described in conjunction with one or some embodiments also apply to other embodiments. Unless expressly specified otherwise, the terms "include", "comprise", "have", and variations thereof mean "including but not limited to".

[0023] Unless expressly specified otherwise, the enumerated listing of items does not imply that any or all of the items are mutually exclusive.Unless expressly specified otherwise, the terms "a", "an" and "the" also mean "one or more".

[0024] Throughout the disclosure, the terms "first", "second", "third", etc. are used as terms that are used only to refer to related devices, components, procedural steps, etc., without indicating any spatial or temporal order, unless otherwise explicitly specified. For example, "first device" and "second device" may refer to two separately formed devices, or two parts or components of the same device. In some cases, for example, "first device" and "second device" may be the same and may be named arbitrarily. Similarly, the "first step" of a method or process may be performed or carried out after or simultaneously with the "second step".

[0025] It should be understood that the term "and / or" used herein refers to and includes any and all possible combinations of one or more associated listed items. For example, "A and / or B" may refer to any of the following three combinations: only A exists, only B exists, and A and B exist together. The character " / " generally indicates an "or" relationship of associated items. However, this may also include an "and" relationship of associated items. For example, "A / B" means "A or B", which may also include the co-existence of A and B, unless the context indicates otherwise.

[0026] In addition, the features, structures or characteristics of the described embodiments may be combined in any suitable manner. In the following description, a plurality of specific details are provided, such as examples of programming, software modules, user selections, network transactions, database queries, database structures, hardware modules, hardware circuits, hardware chips, etc., to provide a thorough understanding of the embodiments. However, those skilled in the relevant art will recognize that the embodiments may be practiced without one or more specific details or using other methods, components, materials, etc. In other instances, known structures, materials or operations are not shown or described in detail to avoid confusing aspects of the embodiments.

[0027] Aspects of various embodiments are described below with reference to schematic flow charts and / or schematic block diagrams of methods, apparatus, systems, and program products. It will be understood that each step in the schematic flow charts and / or schematic block diagrams, and combinations of steps in the schematic flow charts and / or schematic block diagrams, can be implemented by code. The code can be provided to a processor of a general-purpose computer, a special-purpose computer, or other programmable data processing device to produce a machine so that instructions executed by a processor of a computer or other programmable data processing device can create a device for implementing the functions or actions specified in the schematic flow charts and / or schematic block diagrams.

[0028] The code may also be stored in a storage device that can direct a computer, other programmable data processing device, or other device to function in a specific manner so that the instructions stored in the storage device produce an article of manufacture including instructions that implement the functions or actions specified in the schematic flowchart and / or schematic block diagram.

[0029] The schematic flow charts and / or schematic block diagrams in the accompanying drawings illustrate the architecture, functions and operations of possible implementations of different devices, systems, methods and program products according to various embodiments. In this regard, each step in the schematic flow chart and / or schematic block diagram can represent a module, segment or portion of a code, which includes one or more executable instructions for implementing the code of the specified logical function. However, those skilled in the relevant art will recognize that the flow chart is not necessarily practiced in the order shown and can be practiced without one or more specific steps or practiced using other steps not shown.

[0030] It should also be noted that in some alternative implementations, the functions annotated in the identified blocks may not appear in the order annotated in the drawings. For example, two blocks shown in succession may actually be executed simultaneously, or may sometimes be executed in the reverse order, depending on the functions involved. Other steps and methods that are equivalent in function, logic, or effect to one or more blocks or portions thereof of the illustrated drawings may be envisioned.

[0031] Figure 11 is a schematic diagram illustrating a wireless communication system. It depicts an embodiment of a wireless communication system 100. In one embodiment, the wireless communication system 100 may include a user equipment (UE) 102 and a network equipment (NE) 104. Figure 1 A specific number of UEs 102 and NEs 104 are depicted in FIG. 1 , but those skilled in the art will recognize that any number of UEs 102 and NEs 104 may be included in the wireless communication system 100 .

[0032] UE 102 may be referred to as a remote device, a remote unit, a subscriber unit, a mobile station, a mobile station, a user, a terminal, a mobile terminal, a fixed terminal, a subscriber station, a user terminal, a device, an apparatus or other terminology used in the art.

[0033] In one embodiment, the UE 102 may be an autonomous sensor device, an alarm device, an actuator device, a remote control device, etc. In some other embodiments, the UE 102 may include a computing device such as a desktop computer, a laptop computer, a personal digital assistant (PDA), a tablet computer, a smart phone, a smart TV (e.g., a TV connected to the Internet), a set-top box, a game console, a security system (including security cameras), a vehicle-mounted computer, a network device (e.g., a router, a switch, a modem), etc. In some embodiments, the UE 102 includes a wearable device such as a smart watch, a fitness band, an optical head-mounted display, etc. The UE 102 may communicate directly with one or more of the NEs 104.

[0034] NE 104 may also be referred to as a base station, access point, access terminal, base, Node-B, eNB, gNB, home Node-B, relay node, device, equipment, or any other term used in the art. Throughout this specification, references to base stations may refer to any of the above reference types of network devices 104 such as eNBs and gNBs.

[0035] The NEs 104 may be distributed over a geographic area. The NEs 104 are typically part of a radio access network that includes one or more controllers communicatively coupled to one or more corresponding NEs 104. The radio access network is typically communicatively coupled to one or more core networks, which may be coupled to other networks, such as the Internet and a public switched telephone network. These and other elements of the radio access and core networks are not illustrated, but are well known to those of ordinary skill in the art.

[0036] In one embodiment, the wireless communication system 100 complies with 3GPP 5G New Radio (NR). In some embodiments, the wireless communication system 100 complies with the 3GPP protocol, wherein the NE 104 transmits on the DL using an OFDM modulation scheme, and the UE 102 transmits on the UL using an SC-FDMA scheme or an OFDM scheme. However, more generally, the wireless communication system 100 may implement some other open or proprietary communication protocols, such as WiMAX. The present disclosure is not intended to be limited to any particular wireless communication system architecture or protocol implementation.

[0037] NE 104 can serve multiple UEs 102 within a service area, such as a cell (or cell sector) or more cells, via wireless communication links. NE 104 sends DL communication signals to serve UE 102 in time, frequency, and / or spatial domains.

[0038] A communication link is provided between the NE 104 and the UEs 102a, 102b, 102c, and 102d, which may be, for example, a NR UL or DL ​​communication link. Some UEs 102 may communicate with different radio access technologies (RATs) such as NR and LTE simultaneously. A direct or indirect communication link may be provided between two or more NEs 104.

[0039] The NE 104 may also include one or more transmit receive points (TRPs) 104a. In some embodiments, the network device may be a gNB 104 that controls multiple TRPs 104a. In addition, there is a backhaul between two TRPs 104a. In some other embodiments, the network device may be a TRP 104a controlled by a gNB.

[0040] A communication link is provided between the NE 104, 104a and the UE 102, 102a, respectively, which may be, for example, a NR UL / DL communication link. Some UEs 102, 102a may communicate simultaneously with different radio access technologies (RATs) such as NR and LTE.

[0041] In some embodiments, a UE 102a may be able to simultaneously communicate with two or more TRPs 104a utilizing a non-ideal backhaul. A TRP may be a transmission point of a gNB. The UE and / or (one or more) TRPs may use multiple beams. The two or more TRPs may be TRPs of different gNBs, or may be the same gNB. That is, different TRPs may have the same cell ID or different cell IDs. The terms "TRP" and "transmit-receive identity" may be used interchangeably throughout the disclosure.

[0042] At least some of the disclosed techniques or examples may be applicable to scenarios with or without multiple TRPs as long as multiple PDCCH transmissions are supported.

[0043] Figure 2 2 is a schematic block diagram illustrating components of a user equipment (UE) according to one embodiment. UE 200 may include a processor 202, a memory 204, an input device 206, a display 208, and a transceiver 210. In some embodiments, the input device 206 and the display 208 are combined into a single device, such as a touch screen. In some embodiments, UE 200 may not include any input device 206 and / or display 208. In various embodiments, UE 200 may include one or more processors 202 and may not include an input device 206 and / or display 208.

[0044] In one embodiment, the processor 202 may include any known controller capable of executing computer-readable instructions and / or capable of performing logical operations. For example, the processor 202 may be a microcontroller, a microprocessor, a central processing unit (CPU), a graphics processing unit (GPU), an auxiliary processing unit, a field programmable gate array (FPGA), or a similar programmable controller. In some embodiments, the processor 202 executes instructions stored in the memory 204 to perform the methods and routines described herein. The processor 202 is communicatively coupled to the memory 204 and the transceiver 210.

[0045] In one embodiment, memory 204 is a computer-readable storage medium. In some embodiments, memory 204 includes volatile computer storage media. For example, memory 204 may include RAM, including dynamic RAM (DRAM), synchronous dynamic RAM (SDRAM), and / or static RAM (SRAM). In some embodiments, memory 204 includes non-volatile computer storage media. For example, memory 204 may include a hard drive, flash memory, or any other suitable non-volatile computer storage device. In some embodiments, memory 204 includes both volatile and non-volatile computer storage media. In some embodiments, memory 204 stores data related to the triggering condition for sending the measurement report to the network device. In some embodiments, memory 204 also stores program code and related data.

[0046] In one embodiment, input device 206 may include any known computer input device, including a touch panel, buttons, keyboard, stylus, microphone, etc. In some embodiments, input device 206 may be integrated with display 208, for example, as a touch screen or similar touch-sensitive display.

[0047] In one embodiment, the display 208 may include any known electronically controllable display or display device. The display 208 may be designed to output visual, audio and / or tactile signals.

[0048] In one embodiment, the transceiver 210 is configured to communicate wirelessly with a network device. In some embodiments, the transceiver 210 includes a transmitter 212 and a receiver 214. The transmitter 212 is used to send UL communication signals to the network device, and the receiver 214 is used to receive DL communication signals from the network device.

[0049] The transmitter 212 and the receiver 214 may be any suitable type of transmitter and receiver. Although only one transmitter 212 and one receiver 214 are shown, the transceiver 210 may have any suitable number of transmitters 212 and receivers 214. For example, in some embodiments, the UE 200 includes multiple transmitter 212 and receiver 214 pairs for communicating on multiple wireless networks and / or radio frequency bands, and each transmitter 212 and receiver 214 pair is configured to communicate on a different wireless network and / or radio frequency band.

[0050] Figure 3 3 is a schematic block diagram illustrating components of a network device (NE) 300 according to one embodiment. The NE 300 may include a processor 302, a memory 304, an input device 306, a display 308, and a transceiver 310. As can be appreciated, in some embodiments, the processor 302, the memory 304, the input device 306, the display 308, and the transceiver 310 may be similar to the processor 202, the memory 204, the input device 206, the display 208, and the transceiver 210 of the UE 200, respectively.

[0051] In some embodiments, the processor 302 controls the transceiver 310 to send a DL signal or data to the UE 200. The processor 302 may also control the transceiver 310 to receive a UL signal or data from the UE 200. In another example, the processor 302 may control the transceiver 310 to send a DL signal containing various configuration data to the UE 200.

[0052] In some embodiments, the transceiver 310 includes a transmitter 312 and a receiver 314. The transmitter 312 is used to send DL communication signals to the UE 200, and the receiver 314 is used to receive UL communication signals from the UE 200.

[0053] The transceiver 310 may communicate with multiple UEs 200 simultaneously. For example, the transmitter 312 may send DL communication signals to the UE 200. As another example, the receiver 314 may simultaneously receive UL communication signals from the UE 200. The transmitter 312 and the receiver 314 may be any suitable type of transmitter and receiver. Although only one transmitter 312 and one receiver 314 are shown, the transceiver 310 may have any suitable number of transmitters 312 and receivers 314. For example, the NE 300 may serve multiple cells and / or cell sectors, wherein the transceiver 310 includes a transmitter 312 and / or a receiver 314 for each cell or cell sector.

[0054] With multiple TRPs, the PDCCH for one DCI can be sent multiple times through different time, frequency and / or spatial resources. Based on the principle of the beam failure detection mechanism of Release 15, a beam failure event occurs when the quality of the beam pair link of the associated control channel drops sufficiently low. With enhanced PDCCH transmission, the corresponding beam pair link of the associated control channel will be improved by multiple transmissions and / or multiple beams. Therefore, the beam failure detection mechanism can be enhanced to match the newly introduced multiple PDCCH transmissions.

[0055] For beam failure detection, only a single PDCCH transmission is assumed for evaluating beam failure in Release 15 NR systems. For PDCCH with multiple transmissions, the beam failure status needs to be determined by considering multiple transmissions and / or multiple beams.

[0056] In Release 15 or Release 16, only one (1) TCI state is activated for PDCCH transmission. Periodic Channel State Information Reference Signal (CSI-RS) Resource Set It may be configured for beam failure detection, where up to two (2) beam failure detection resources are configured for the BWP of the serving cell. The link quality is evaluated based on the measurement of each detection resource. When multiple beams from multiple TRPs are used for PDCCH transmission, the link quality may be evaluated based on the measurement of multiple reference signals (RS). Therefore, in the case where multiple transmit beams are used, it is necessary to clarify the beam failure detection resources used for multiple PDCCH transmissions.

[0057] A signaling mechanism for aligning the assumed PDCCH transmission scheme for beam failure detection may be considered. With the introduction of beam failure detection mechanism for multiple PDCCH transmissions, the UE may have two behaviors for determining beam failure. The gNB and UE should have the same understanding of the assumed PDCCH transmission scheme for clarifying beam failure events.

[0058] Through failureDetectionResources or beamFailureDetectionResourceList for radio link quality measurement on the BWP of the serving cell, the UE may be provided with a set of periodic CSI-RS resource configuration indices for each BWP of the serving cell. The beam failure detection RS resource is configured via the RadioLinkMonitoringConfig as shown in the following information element (IE). N LR-RLM RadioLinkMonitoringRS, a maximum of two RadioLinkMonitoringRS can be used for link recovery. The UE expects this set Includes up to two RS indices. UE expected set A single port in RS.

[0059]

[0060] If the BWP for the serving cell does not provide the UE with The UE determines the set includes a periodic CSI-RS resource index having the same value as an RS index in the RS set indicated by TCI-State for the respective CORESET used by the UE to monitor the PDCCH, and if there are two RS indices in the TCI state, the set Includes RS index with QCL-Type D configuration for corresponding TCI state.

[0061] UE shall be based on the set The reference signals in the set are used to assess the downlink quality of the serving cell in order to detect beam failure instances. The RS resources in the set can be periodic CSI-RS resources and / or synchronization signal block (SSB) resources. On each RS resource in out,LR The comparison is performed for the purpose of downlink radio link quality of the access serving cell.

[0062] Threshold Q out,LR Corresponds to the default value of rlmInSyncOutOfSyncThreshold, i.e., the BLER threshold for generating an in-sync / out-of-sync (IS / OOS) indication for the out-of-sync block error rate (BLER out), where the default value is 10%. The threshold Q out,LR can be defined as the level at which the downlink radio link cannot be reliably received and may correspond to the BLER of an assumed PDCCH transmission out =10% block error rate.

[0063] For SSB-based beam failure detection, Q out_LR_SSB It can be derived based on the assumed PDCCH transmission parameters as specified in TS 38.133. The UE should be able to evaluate the Evaluate_BFD_SSB [ms] period estimated in the collection Whether the downlink radio link quality on the SSB resources configured in T Evaluate_BFD_SSB [ms] Threshold Q within period out_LR_SSB Similarly, for CSI-RS based beam failure detection, Q out_LR_CSI-RS It can be derived based on the assumed PDCCH transmission parameters as specified in TS 38.133. The UE should be able to evaluate the Evaluate_BFD_CSI-RS [ms] period estimated in the collection Whether the downlink radio link quality on the CSI-RS resources configured in T Evaluate_BFD_CSI-RS [ms] Threshold Q within period out_LR_CSI-RS Difference.

[0064] In non-discontinuous reception (non-DRX) mode operation, when the UE uses the set of The radio link quality ratio threshold Q of all corresponding resource configurations in out,LR When the radio link quality is lower than the threshold Q out,LR When the difference is small, the physical layer uses the shortest periodicity among the periodic CSI-RS configurations and / or the set used by the UE to assess the radio link quality. The maximum period determined by the SS / PBCH block on the primary cell (PCell) or primary secondary cell (PSCell) in the primary cell (PCell) and 2 milliseconds is used to notify the higher layer. In the discontinuous reception (DRX) mode operation, when the radio link quality is lower than the threshold Q out,LR The differential time physical layer provides indications to higher layers with a periodicity defined in TS38.133.

[0065] In some examples, the number of beam failure instances detected within a time period (e.g., beamFailureDetectionTimer) may be counted, and a beam failure recovery procedure or a random access procedure may be triggered once the number reaches a preset maximum value (e.g., beamFailureInstanceMaxCount). The behavior of the MAC entity for each serving cell configured for beam failure detection is defined as follows in TS38.321. The present disclosure is primarily directed to the beam failure detection scheme / procedure in the physical layer. For MAC layer processing of physical layer reports, the current scheme / procedure can be reused as shown in the following table defined in TS38.321.

[0066]

[0067] In view of multiple transmission beams, an enhanced configuration and implicit determination principle for beam failure detection resources is proposed. Thresholds and transmission parameters for assuming a PDCCH transmission scheme are defined based on multiple PDCCH transmissions. In addition, signaling is introduced to align the gNB and UE under the assumption of a PDCCH transmission scheme for beam failure assessment.

[0068] exist Figure 4A and 4B Two exemplary systems for multiple transmissions of DPCCH for DCI using multiple TRPs are shown in . One DCI is sent to UE 430 from multiple TRPs 410, 420 through multiple repeated transmissions, where each repeated transmission is monitored at one PDCCH monitoring opportunity.

[0069] Based on the actual application scenario, one or more CORESETs can be configured for PDCCH transmission. Figure 4A In the case of only one CORESET configuration with CORESET 0 shown in , multiple DCI repetitions are sent in multiple monitoring occasions in one search space set (search space k). Multiple PDCCH transmissions can come from a single CORESET (CORESET 0) with multiple TCI states (e.g., TCI state 1 and TCI state 2).

[0070] In such Figure 4B In the case of multiple CORESET configurations with CORESET 0 and CORESET 1 shown, multiple DCI repetitions are sent in multiple monitoring opportunities in multiple search space sets (search space k and search space k+1). Multiple PDCCH transmissions can be from multiple CORESETs (CORESET0 and CORESET1) with one TCI state for each CORESET (e.g., CORESET 0 is TCI state 1 and CORESET 1 is TCI state 2).

[0071] In some examples, only two PDCCH monitoring opportunities (Opportunity 1 and Opportunity 2) in a time slot may be supported for two repetitions; in some other examples, four PDCCH monitoring opportunities (Opportunities 1, 2, 3, and 4) in a time slot may be supported for four repetitions. Several transmission modes for TCI states are possible, for example, if two TCI states are used for multiple PDCCH transmissions, then [1 2] or [1 1 2 2], and if only one TCI state is used for multiple PDCCH transmissions, then

[11] or [1 1 1 1]. Here, the numbers "1" and "2" in "[1 2]" refer to TCI state 1 for the first transmission and TCI state 2 for the second transmission, respectively.

[0072] Beam Fault Detection Resources

[0073] For Release 15 / Release 16 beam failure detection, only one configured detection resource or one detection resource linked with PDCCH monitoring is used for one candidate link quality assessment, where PDCCH is assumed to be transmitted only once (1). For PDCCH enhancement in Release 17, multiple PDCCH transmissions may be introduced for one DCI, where different TCI states may be used for multiple transmissions. Therefore, multiple beam failure detection resources may be used together for one candidate link quality assessment.

[0074] In some examples, if a beam failure detection RS set is configured The combined detection resource (i.e., a beam failure detection resource combination including a large number of beam failure detection resources) may be configured with multiple SSB and / or CSI-RS resources for joint link quality assessment for PDCCH with multiple transmissions. The UE may receive a configuration beam failure detection RS set configuration signaling, and determine the beam fault detection resource combination based on the configuration signaling.

[0075] When RadioLinkMonitoringRS is used to configure detection resources for beam failure detection, an additional parameter detectionResourceCombination may be introduced, where there are maxNrofdetectionResourcePerCombination (eg 2) detection resources for joint link quality assessment. An example of information elements for Radio Resource Control (RRC) signaling design is illustrated below.

[0076]

[0077] A new candidate beam list for secondary cell (SCell) beam failure detection was introduced in Release 16. A similar design can be used for beamFailureDetectionResourceList, where beamFailureDetectionResourceCombination is introduced in beamFailureDetectionResourceList to support multiple beams for joint SCell link quality assessment. An example of information elements for RRC signaling design is illustrated below.

[0078]

[0079] Because the same or different TCI states can be used for PDCCH with multiple transmissions, the repeat number (i.e., the number of PDCCH transmissions for one DCI) can be configured separately for each beam failure detection RS. It can be used to evaluate the link quality used by the assumed PDCCH transmission scheme. As an implementation example, as shown in the RRC IE design above, optional signaling of repeat-Num is added in the beam failure detection resource configuration.

[0080] In some other examples, when the beam failure detection RS set is not configured When the detection resources corresponding to the multiple activated TCI states for PDCCH monitoring are used for joint link quality assessment, the UE may determine the beam failure detection resource combination from the resources having the same TCI state as one of the multiple activated TCI states for PDCCH monitoring.

[0081] If the BWP for the serving cell does not provide the UE with The UE determines the set The periodic CSI-RS resource configuration index has the same value as the RS index in the RS set of the respective CORESET for the UE to monitor the PDCCH indicated by TCI-State. If there are two RS indices in the TCI state, the set Includes RS index with QCL-Type D configuration for corresponding TCI state.

[0082] When multiple CORESETs are configured to monitor PDCCH for one DCI transmission and one TCI state is activated for each CORESET, the detection resources corresponding to the activated TCI states for the multiple CORESETs may be jointly set at It is used for link quality assessment.

[0083] Similarly, when a single CORESET with multiple activated TCI states is configured to monitor PDCCI for one DCI transmission, the detection resources corresponding to the multiple activated TCI states may be jointly set at It is used for link quality assessment.

[0084] When assessing whether the quality of a beam (or beam pair) has degraded to 10% BLER, the UE uses the same assumption of the number of repetitions of each DCI transmission (i.e., the number of PDCCH transmissions for one DCI) in a single or multiple CORESETs. The TCI state used for PDCCH monitoring can be changed by the MAC CE. However, link recovery has a joint Layer 1 + Layer 2 process, and the link quality assessment requires a duration for robustness requirements. Therefore, it may not be preferred to support fast switching of link quality assessment assumptions between a single PDCCH transmission and multiple PDCCH transmissions. When link quality assessment is performed based on assumed multiple PDCCH transmissions but only one TCI state is used for one actual PDCCH transmission or only one TCI state for assumed multiple PDCCHs is updated, two alternatives can be used for the UE to determine the set In one example, the detection resource corresponding to the TCI state for the previous multiple PDCCH transmissions can be set to That is, the beam failure detection resource corresponds to the last used TCI state of multiple transmissions of the PDCCH. Alternatively, the detection resource corresponding to the latest TCI state of each CORESET used for multiple PDCCH transmissions may be set to That is, each of the beam failure detection resources corresponds to the latest TCI state of each CORESET for multiple transmissions of the PDCCH.

[0085] Beam Fault Detection Process

[0086] The physical layer in the UE is based on the threshold Q out,LR A collection of resource configurations To assess the quality of the radio link. out,LR can be defined as the level at which the downlink radio link cannot be reliably received and should correspond to the BLER of an assumed PDCCH transmission out = 10% Block Error Rate. Since one DCI is actually sent multiple times via PDCCH, it is best to treat it as a hypothetical PDCCH transmission to match the actual downlink radio link quality. BLER out= 10% block error rate target may not change because it is well defined and used for Release 15 or Release 16 NR systems. Therefore, a BLER based on a hypothetical PDCCH with multiple transmissions is proposed. out = 10% block error rate target to derive the additional threshold Q out,LR .

[0087] In some examples, the threshold Q for a hypothetical PDCCH with multiple transmissions is out,LR This can be done by modifying the threshold Q in version 15 or version 16 of TS38.133 out,LR to define by the definition of .

[0088] Given that there are multiple PDCCH transmissions, the threshold Q out,LR can be redefined as follows.

[0089]

[0090] For example, the number of PDCCH transmissions and the related TCI state switching mode may also be added to the PDCCH transmission parameter list, such as Table 1 for SSB as detection resource (updated based on Table 8.5.2.1-1 in TS 38.133) and Table 2 for CSI-RS as detection resource (updated based on Table 8.5.3.1-1 in TS 38.133). For a beam failure detection instance, the UE measures the jointly configured resources linked to multiple transmissions. Based on the implementation algorithm, it derives an equivalent Q value (i.e., a value reflecting the link quality) based on the measurement results, where each transmission is linked to the measurement results. The UE can compare the equivalent Q with the threshold Q out,LR The comparison is performed to determine whether a beam failure occurs for the instance. That is, after determining the beam failure detection resource combination, or the beam failure detection resource, the UE receives a signal from at least one of the beam failure detection resources and determines the link quality based on the measurement of the received signal. The UE may determine the link quality based on the link quality and the threshold Q. out,LR Generates beam fault assessment report.

[0091] Table 1 PDCCH transmission parameters for beam failure case

[0092]

[0093] Table 2 PDCCH transmission parameters for beam failure case

[0094]

[0095]

[0096] Threshold Q out,LRand Q in,LR They correspond to the default values ​​of rlmInSyncOutOfSyncThreshold, as specified in TS38.133 for Q out The threshold Q is given by rsrp-ThresholdSSB or rsrp-ThresholdSSBBFR. out,LR The number of PDCCH transmissions and / or the TCI state switching pattern for a hypothetical PDCCH with multiple transmissions may be configured / predefined, or alternatively, the configured values ​​as for actual PDCCH transmissions may be reused.

[0097] As an example of a configuration for a hypothetical PDCCH with multiple transmissions, the number of PDCCH transmissions may be 2 or 4. The TCI state switching pattern may be [1 2] or [1 1 2 2] for 2 activated TCI states with 2 or 4 transmissions, and may be [1 1] or [1 1 1 1] for 1 activated TCI state with 2 or 4 transmissions. In some examples, multiple transmissions of a PDCCH with a single TCI state can act as one hypothetical PDCCH transmission scheme. In this case, enhancements for beam failure detection resources are not required. As shown in Table 2, the number of PDCCH transmissions may be predefined to align the understanding between the gNB and the UE. Therefore, for the case of only one TCI state, a TCI switching pattern (i.e., [1 1] or [1 1 1 1]) may not be required.

[0098] Note that there are multiple candidate PDCCH transmission schemes (or hypothetical PDCCH transmission schemes), which include the PDCCH transmission scheme of Release 15 or Release 16 and the enhanced multiple PDCCH transmission scheme. If different hypothetical PDCCH transmission schemes are assumed, different thresholds Q will be used at the UE side. out,LRto evaluate the beam failure status. That is, it may be desirable to have the same understanding of the assumed hypothetical PDCCH transmission scheme for beam failure detection. The actual PDCCH transmission scheme used may be related to the UE capabilities and the actual system status, for example, the system PDCCH load. Specifically, the UE may report its capabilities to indicate whether it is able to support an enhanced beam failure detection scheme (e.g., hypothetical beam failure detection with multiple PDCCH transmissions). The reported capabilities may further include the supported detection RS / RS combination number and component RS number in one RS combination. The GNB has the ability to select a PDCCH transmission scheme based on the UE reported capabilities and the actual system load status. Therefore, signaling may be introduced to indicate the UE's assumed PDCCH transmission scheme for beam failure detection. For example, 1 bit of signaling may be used to indicate whether the assumed PDCCH transmission scheme is a normal version 15 / version 16 PDCCH transmission scheme or an enhanced version 17 PDCCH multiple transmission scheme.

[0099] Figure 5 is a flow chart illustrating the steps of a beam failure detection mechanism for an enhanced PDCCH with multiple transmissions by a UE according to some embodiments of the present disclosure.

[0100] At step 502, the processor 202 of the UE 200 determines a beam failure detection resource combination, or beam failure detection resources, for detecting beam failures of multiple transmissions of a physical downlink control channel (PDCCH) for downlink control information (DCI), wherein the beam failure detection resource combination includes multiple beam failure detection resources.

[0101] At step 504, the receiver 214 of the UE 200 receives a signal from at least one of the beam failure detection resources.

[0102] At step 506, processor 202 of UE 200 determines link quality based on measurements of signals received from at least one of the beam failure detection resources, determining a threshold based on an assumed PDCCH for multiple transmissions using one or more transmission configuration indication (TCI) states.

[0103] At step 510, the processor 202 of the UE 200 generates a beam failure assessment report based on the link quality and the threshold.

[0104] Figure 6 is a flow chart illustrating the steps of a beam failure detection mechanism for an enhanced PDCCH with multiple transmissions through a NE according to some embodiments of the present disclosure.

[0105] At step 602, the transmitter 312 of the NE 300 sends a signal on a beam failure detection resource combination, or a beam failure detection resource, for detecting a beam failure of multiple transmissions of a physical downlink control channel (PDCCH) for downlink control information (DCI), wherein the beam failure detection resource combination includes multiple beam failure detection resources.

[0106] At step 604, the receiver 314 of the NE 300 receives a beam failure report generated based on a link quality determined based on measurements of signals received from a plurality of beam failure detection resources and a threshold determined based on a hypothetical PDCCH with a plurality of transmissions.

[0107] Various embodiments and / or examples are disclosed to provide exemplary and explanatory information to enable those skilled in the art to put the present disclosure into practice. Unless otherwise specifically indicated, features or components disclosed with reference to one embodiment or example also apply to all embodiments or examples.

[0108] Embodiments may be practiced in other specific forms. The described embodiments should be considered in all respects as merely illustrative and not restrictive. Therefore, the scope of the present invention is indicated by the appended claims rather than by the foregoing description. All changes within the meaning and scope of the equivalents of the claims are encompassed within their scope.

Claims

1. A user equipment (UE), comprising: A processor, the processor determining a beam failure detection resource combination or a beam failure detection resource for detecting beam failures of multiple transmissions of a physical downlink control channel PDCCH for one downlink control information DCI from multiple transmission receiving points, wherein the beam failure detection resource combination includes multiple beam failure detection resources; as well as a receiver that receives a signal from at least one of the beam failure detection resources; wherein the processor further determines link quality based on a measurement of the signal received from at least one of the beam failure detection resources, and determines a threshold based on a hypothetical PDCCH having a plurality of transmissions indicating a TCI state using one or more transmission configurations; as well as The processor further generates a beam failure assessment report based on the link quality and the threshold.

2. The UE according to claim 1, wherein: The receiver further receives configuration signaling, and the processor determines the beam failure detection resource combination based on the configuration signaling.

3. The UE according to claim 1, wherein: The multiple beam failure detection resources include channel state information reference signal CSI-RS resources and / or synchronization signal block SSB resources.

4. The UE according to claim 1, wherein: The processor implicitly determines the beam failure detection resource combination from resources having a TCI state that is the same as one of a plurality of activated TCI states for PDCCH monitoring.

5. The UE according to claim 4, wherein: Each of the beam failure detection resources corresponds to a latest TCI state for each CORESET used for the plurality of transmissions of the PDCCH.

6. The UE according to claim 4, wherein: The beam failure detection resource corresponds to a last used TCI state for the plurality of transmissions of the PDCCH.

7. The UE according to claim 1, wherein: The processor further determines a list of assumed PDCCH transmission parameters including a number of PDCCH transmissions for DCI and / or a TCI state switching pattern of the PDCCH transmissions.

8. The UE according to claim 1, wherein: The receiver further receives signaling indicating a hypothesized PDCCH transmission scheme for the plurality of transmissions of the PDCCH.

9. The UE of claim 1, further comprising a transmitter that transmits a capability report indicating whether assumed beam failure detection with multiple PDCCH transmissions is supported.

10. A network device (NE), comprising: A transmitter, wherein the transmitter sends a signal on a beam failure detection resource combination or a beam failure detection resource for detecting beam failure of multiple transmissions of a physical downlink control channel PDCCH for one downlink control information DCI from multiple transmission and reception points, wherein the beam failure detection resource combination includes multiple beam failure detection resources; as well as A receiver that receives a beam failure report generated based on a link quality and a threshold, wherein the link quality is determined based on a measurement of signals received from the plurality of beam failure detection resources and the threshold is determined based on a hypothetical PDCCH having the plurality of transmissions.

11. The NE according to claim 10, wherein: The transmitter further sends configuration signaling for determining the beam failure detection resource combination.

12. The NE according to claim 10, wherein: The multiple beam failure detection resources include channel state information reference signal CSI-RS resources and / or synchronization signal block SSB resources.

13. The NE according to claim 10, wherein: The transmitter further sends signaling indicating an assumed PDCCH transmission scheme for the plurality of transmissions of the PDCCH.

14. The NE according to claim 10, wherein: The receiver further receives a capability report indicating whether assumed beam failure detection with multiple PDCCH transmissions is supported.

15. A method performed by a user equipment (UE), comprising: Determining, by a processor, a beam failure detection resource combination or a beam failure detection resource for detecting beam failures of multiple transmissions of a physical downlink control channel PDCCH for one downlink control information DCI from multiple transmission and reception points, wherein the beam failure detection resource combination includes multiple beam failure detection resources; as well as receiving, by a receiver, a signal from at least one of the beam failure detection resources; determining, by the processor, a link quality based on a measurement of the signal received from at least one of the beam failure detection resources, determining a threshold based on a hypothesized PDCCH having a plurality of transmissions indicating a TCI state using one or more transmission configurations; as well as A beam failure assessment report is generated, by the processor, based on the link quality and the threshold.

16. The method according to claim 15, wherein: The receiver further receives configuration signaling, and the processor determines the beam failure detection resource combination based on the configuration signaling.

17. The method according to claim 15, wherein: The multiple beam failure detection resources include channel state information reference signal CSI-RS resources and / or synchronization signal block SSB resources.

18. The method according to claim 15, wherein: The processor implicitly determines the beam failure detection resource combination from resources having a TCI state that is the same as one of a plurality of activated TCI states for PDCCH monitoring.

19. The method according to claim 18, wherein: Each of the beam failure detection resources corresponds to a latest TCI state for each CORESET used for the plurality of transmissions of the PDCCH.

20. The method according to claim 18, wherein: The beam failure detection resource corresponds to a last used TCI state for the plurality of transmissions of the PDCCH.

21. The method according to claim 15, wherein: The processor further determines a list of assumed PDCCH transmission parameters including a number of PDCCH transmissions for DCI and / or a TCI state switching pattern of the PDCCH transmissions.

22. The method according to claim 15, wherein: The receiver further receives signaling indicating a hypothesized PDCCH transmission scheme for the plurality of transmissions of the PDCCH.

23. The method of claim 15, further comprising sending, by the transmitter, a capability report indicating whether assumed beam failure detection with multiple PDCCH transmissions is supported.

24. A method performed by a network device (NE), comprising: A signal is sent by a transmitter on a beam failure detection resource combination or a beam failure detection resource for detecting beam failures of multiple transmissions of a physical downlink control channel PDCCH for one downlink control information DCI from multiple transmission and reception points, wherein the beam failure detection resource combination includes multiple beam failure detection resources; as well as A beam failure report generated based on a link quality and a threshold is received by a receiver, wherein the link quality is determined based on a measurement of signals received from the plurality of beam failure detection resources, and the threshold is determined based on a hypothesized PDCCH having the plurality of transmissions.

25. The method according to claim 24, wherein: The transmitter further sends configuration signaling for determining the beam failure detection resource combination.

26. The method according to claim 24, wherein: The multiple beam failure detection resources include channel state information reference signal CSI-RS resources and / or synchronization signal block SSB resources.

27. The method according to claim 24, wherein: The transmitter further sends signaling indicating an assumed PDCCH transmission scheme for the plurality of transmissions of the PDCCH.

28. The method of claim 24, wherein: The receiver further receives a capability report indicating whether assumed beam failure detection with multiple PDCCH transmissions is supported.

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