WO2023147705A1

WO2023147705A1 - Methods, devices, and computer readable medium for communication

Info

Publication number: WO2023147705A1
Application number: PCT/CN2022/075406
Authority: WO
Inventors: Gang Wang
Original assignee: Nec Corporation
Priority date: 2022-02-07
Filing date: 2022-02-07
Publication date: 2023-08-10

Abstract

Methods, devices, and computer readable medium for communication are disclosed. According to embodiments of the present disclosure, a network device transmits a configuration associated with a radio link monitoring/beam failure detection (RLM/BFD) relaxation to a terminal device. The terminal device determines whether criteria for the RLM/BFD relaxation are fulfilled. If the criteria for the RLM/BFD relaxation are fulfilled, the terminal device transmits a report indicating entering the RLM/BFD relaxation to the network device. The terminal device performs the RLM/BFD relaxation after the transmission of the report. In this way, it is more flexible to report entering or leaving the RLM/BFD relaxation. Moreover, it can also save the number of bits in the report.

Description

METHODS, DEVICES, AND COMPUTER READABLE MEDIUM FOR COMMUNICATION

TECHNICAL FIELD

Embodiments of the present disclosure generally relate to the field of telecommunication, and in particular, to methods, devices, and computer readable medium for communication.

BACKGROUND

Several technologies have been proposed to improve communication performances. For example, a technology called “beamforming” has been proposed. Beamforming is a particular processing for signals that allow for directional transmission or reception. In order to ensure communication quality, the terminal device needs to monitor whether a beam failure occurs. If a beam failure occurs when there is a change of a surrounding environment, the terminal device can report this beam failure and request for a recovery of the beam.

SUMMARY

In general, example embodiments of the present disclosure provide a solution for communication.

In a first aspect, there is provided a method for communication. The method comprises receiving, at a terminal device and from a network device, a configuration associated with a radio link monitoring/beam failure detection (RLM/BFD) relaxation; determining whether criteria for the RLM/BFD relaxation are fulfilled; in accordance with a determination that the criteria for the RLM/BFD relaxation are fulfilled, transmitting, to the network device, a report indicating entering the RLM/BFD relaxation; and performing the RLM/BFD relaxation after the transmission of the report; or in accordance with a determination that the criteria for the RLM/BFD relaxation are not fulfilled, transmitting, to the network device, the report indicating leaving the RLM/BFD relaxation.

In a second aspect, there is provided a method for communication. The method comprises transmitting, at a network device and to a terminal device, a configuration associated with a radio link monitoring/beam failure detection (RLM/BFD) relaxation; and receiving, from the terminal device, a report associated with the RLM/BFD relaxation.

In a third aspect, there is provided a terminal device. The terminal device comprises a processing unit; and a memory coupled to the processing unit and storing instructions thereon, the instructions, when executed by the processing unit, causing the terminal device to perform acts comprising: receiving, from a network device, a configuration associated with a radio link monitoring/beam failure detection (RLM/BFD) relaxation; determining whether criteria for the RLM/BFD relaxation are fulfilled; in accordance with a determination that the criteria for the RLM/BFD relaxation are fulfilled, transmitting, to the network device, a report indicating entering the RLM/BFD relaxation; and performing the RLM/BFD relaxation after the transmission of the report; or in accordance with a determination that the criteria for the RLM/BFD relaxation are not fulfilled, transmitting, to the network device, the report indicating leaving the RLM/BFD relaxation.

In a fourth aspect, there is provided a network device. The network device comprises a processing unit; and a memory coupled to the processing unit and storing instructions thereon, the instructions, when executed by the processing unit, causing the network device to perform acts comprising: transmitting, to a terminal device, a configuration associated with a radio link monitoring/beam failure detection (RLM/BFD) relaxation; and receiving, from the terminal device, a report associated with the RLM/BFD relaxation.

In a fifth aspect, there is provided a computer readable medium having instructions stored thereon, the instructions, when executed on at least one processor, causing the at least one processor to carry out the method according to the first or second aspect.

Other features of the present disclosure will become easily comprehensible through the following description.

BRIEF DESCRIPTION OF THE DRAWINGS

Through the more detailed description of some example embodiments of the present disclosure in the accompanying drawings, the above and other objects, features and advantages of the present disclosure will become more apparent, wherein:

Fig. 1 is a schematic diagram of a communication environment in which embodiments of the present disclosure can be implemented;

Fig. 2 illustrates a signaling flow for communications according to some embodiments of the present disclosure;

Fig. 3A illustrates a schematic diagram of regular monitoring occasions according to some embodiments of the present disclosure;

Fig. 3B illustrates a schematic diagram of relaxed monitoring occasions according to some embodiments of the present disclosure;

Fig. 4 illustrates a signaling flow for communications according to some embodiments of the present disclosure;

Fig. 5 illustrates a signaling flow for communications according to some embodiments of the present disclosure;

Fig. 6 is a flowchart of an example method in accordance with an embodiment of the present disclosure;

Fig. 7 is a flowchart of an example method in accordance with an embodiment of the present disclosure; and

Fig. 8 is a simplified block diagram of a device that is suitable for implementing embodiments of the present disclosure.

Throughout the drawings, the same or similar reference numerals represent the same or similar element.

DETAILED DESCRIPTION

Principle of the present disclosure will now be described with reference to some example embodiments. It is to be understood that these embodiments are described only for the purpose of illustration and help those skilled in the art to understand and implement the present disclosure, without suggesting any limitations as to the scope of the disclosure. The disclosure described herein can be implemented in various manners other than the ones described below.

In the following description and claims, unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skills in the art to which this disclosure belongs.

As used herein, the term ‘terminal device’ refers to any device having wireless or wired communication capabilities. Examples of the terminal device include, but not limited to, user equipment (UE) , personal computers, desktops, mobile phones, cellular phones, smart phones, personal digital assistants (PDAs) , portable computers, tablets, wearable devices, internet of things (IoT) devices, Ultra-reliable and Low Latency Communications (URLLC) devices, Internet of Everything (IoE) devices, machine type communication (MTC) devices, device on vehicle for V2X communication where X means pedestrian, vehicle, or infrastructure/network, devices for Integrated Access and Backhaul (IAB) , Space borne vehicles or Air borne vehicles in Non-terrestrial networks (NTN) including Satellites and High Altitude Platforms (HAPs) encompassing Unmanned Aircraft Systems (UAS) , eXtended Reality (XR) devices including different types of realities such as Augmented Reality (AR) , Mixed Reality (MR) and Virtual Reality (VR) , the unmanned aerial vehicle (UAV) commonly known as a drone which is an aircraft without any human pilot, devices on high speed train (HST) , or image capture devices such as digital cameras, sensors, gaming devices, music storage and playback appliances, or Internet appliances enabling wireless or wired Internet access and browsing and the like. The ‘terminal device’ can further has ‘multicast/broadcast’ feature, to support public safety and mission critical, V2X applications, transparent IPv4/IPv6 multicast delivery, IPTV, smart TV, radio services, software delivery over wireless, group communications and IoT applications. It may also incorporate one or multiple Subscriber Identity Module (SIM) as known as Multi-SIM. The term “terminal device” can be used interchangeably with a UE, a mobile station, a subscriber station, a mobile terminal, a user terminal or a wireless device. In the following description, the terms “terminal device” , “communication device” , “terminal” , “user equipment” and “UE” may be used interchangeably.

The terminal device or the network device may have Artificial intelligence (AI) or Machine learning capability. It generally includes a model which has been trained from numerous collected data for a specific function, and can be used to predict some information.

The terminal or the network device may work on several frequency ranges, e.g. FR1 (410 MHz –7125 MHz) , FR2 (24.25GHz to 71GHz) , frequency band larger than 100GHz as well as Terahertz (THz) . It can further work on licensed/unlicensed/shared spectrum. The terminal device may have more than one connection with the network devices under Multi-Radio Dual Connectivity (MR-DC) application scenario. The terminal device or the network device can work on full duplex, flexible duplex and cross division duplex modes.

The term “network device” refers to a device which is capable of providing or hosting a cell or coverage where terminal devices can communicate. Examples of a network device include, but not limited to, a Node B (NodeB or NB) , an evolved NodeB (eNodeB or eNB) , a next generation NodeB (gNB) , a transmission reception point (TRP) , a remote radio unit (RRU) , a radio head (RH) , a remote radio head (RRH) , an IAB node, a low power node such as a femto node, a pico node, a reconfigurable intelligent surface (RIS) , and the like.

In one embodiment, the terminal device may be connected with a first network device and a second network device. One of the first network device and the second network device may be a master node and the other one may be a secondary node. The first network device and the second network device may use different radio access technologies (RATs) . In one embodiment, the first network device may be a first RAT device and the second network device may be a second RAT device. In one embodiment, the first RAT device is eNB and the second RAT device is gNB. Information related with different RATs may be transmitted to the terminal device from at least one of the first network device and the second network device. In one embodiment, first information may be transmitted to the terminal device from the first network device and second information may be transmitted to the terminal device from the second network device directly or via the first network device. In one embodiment, information related with configuration for the terminal device configured by the second network device may be transmitted from the second network device via the first network device. Information related with reconfiguration for the terminal device configured by the second network device may be transmitted to the terminal device from the second network device directly or via the first network device.

Communications discussed herein may use conform to any suitable standards including, but not limited to, New Radio Access (NR) , Long Term Evolution (LTE) , LTE-Evolution, LTE-Advanced (LTE-A) , Wideband Code Division Multiple Access (WCDMA) , Code Division Multiple Access (CDMA) , cdma2000, and Global System for Mobile Communications (GSM) and the like. Furthermore, the communications may be performed according to any generation communication protocols either currently known or to be developed in the future. Examples of the communication protocols include, but not limited to, the first generation (1G) , the second generation (2G) , 2.5G, 2.85G, the third generation (3G) , the fourth generation (4G) , 4.5G, the fifth generation (5G) , and the sixth (6G) communication protocols. The techniques described herein may be used for the wireless networks and radio technologies mentioned above as well as other wireless networks and radio technologies. The embodiments of the present disclosure may be performed according to any generation communication protocols either currently known or to be developed in the future.

The term “circuitry” used herein may refer to hardware circuits and/or combinations of hardware circuits and software. For example, the circuitry may be a combination of analog and/or digital hardware circuits with software/firmware. As a further example, the circuitry may be any portions of hardware processors with software including digital signal processor (s) , software, and memory (ies) that work together to cause an apparatus, such as a terminal device or a network device, to perform various functions. In a still further example, the circuitry may be hardware circuits and or processors, such as a microprocessor or a portion of a microprocessor, that requires software/firmware for operation, but the software may not be present when it is not needed for operation. As used herein, the term circuitry also covers an implementation of merely a hardware circuit or processor (s) or a portion of a hardware circuit or processor (s) and its (or their) accompanying software and/or firmware.

As used herein, the singular forms “a” , “an” and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise. The term “includes” and its variants are to be read as open terms that mean “includes, but is not limited to. ” The term “based on” is to be read as “based at least in part on. ” The term “one embodiment” and “an embodiment” are to be read as “at least one embodiment. ” The term “another embodiment” is to be read as “at least one other embodiment. ” The terms “first, ” “second, ” and the like may refer to different or same objects. Other definitions, explicit and implicit, may be included below.

In some examples, values, procedures, or apparatus are referred to as “best, ” “lowest, ” “highest, ” “minimum, ” “maximum, ” or the like. It will be appreciated that such descriptions are intended to indicate that a selection among many used functional alternatives can be made, and such selections need not be better, smaller, higher, or otherwise preferable to other selections.

As mentioned above, if a beam failure occurs, the terminal device can report this beam failure. The beam failure recover (BFR) for special cell (SpCell) is performed through a random access (RA) procedure. The BFR for secondary cell (SCell) can use medium access control (MAC) control element (CE) based reporting. The term “SpCell” used herein can comprise a primary cell and a primary secondary cell. A terminal device configured with carrier aggregation (CA) has at least a serving cell and it is referred to as a primary cell (PCell) or a primary secondary cell (PSCell) and/or other serving cells are called SCell.

The beam failure detection (BFD) procedure can involve a timer represented as “beamFailureDetectionTimer” and a threshold parameter represented as “beamFailureInstanceMaxCount. ” The parameter “beamFailureDetectionTimer” used herein can refer to a timer for beam failure detection. The value of the beamFailureDetectionTimer can be in number of Q _out, LR reporting periods of Beam Failure Detection reference signal.

Furthermore, there are proposals both in favor and against support of beam failure detection (BFD) while a SCG (including the PSCell and the SCell (s) within the SCG) is deactivated. For radio link monitoring (RLM) support for SCG deactivation, there are some proposals to support RLM for deactivation SCG on PSCell due to SCG activation delay concern and legacy SCGFailureInformation message can be reused after RLM is detected. Some other proposals are not to support RLM because radio resource management (RRM) measurement results are sufficient to evaluate the PSCell coverage.

According to some conventional technologies, RLM can be supported after SCG deactivation and legacy SCGFailureInformation message and reporting procedure can be reused after RLM is detected. Some proposals can support BFD after SCG deactivation. If none of BFD, beam management, channel state information (CSI) is supported, UE always requires random access upon SCG activation which increases the activation delay even if the TA timer is running. BFD on top of already agreed RRM measurements for deactivated SCG is not expected to be very costly in terms of UE power consumption. Some proposals are not to support BFD after SCG deactivation due to UE power consumption concern and doubt the necessary of BFD due to no data activity. Some proposals also think that RRM measurement can compensate the absence of BFD.

If the BFD is supported after SCG deactivation, some proposals are that UE should report BFD occurrence to SCG via master cell group (MCG) . At the same time, the L1 measurement results, beam measurement results can be reported to the network and network indicates the active transmission configuration indicator (TCI) state to perform BFR without triggering random access channel (RACH) . Another proposal is to reuse SCGFailureInformation message.

For UEs for which the network (NW) deactivates secondary cell group (SCG) , the serving beam (s) that was valid previously when SCG was active may easily drift due to UE movement (for example, rotation or changes in the radio environment such as blockage) . Thus, the serving beam (s) may not be valid anymore when the SCG is next time activated for the UE –for instance, after 10 seconds. The behavior for BFD requires UE to count beam failure instances until beamFailureInstanceMaxCount threshold is hit, however, it may take quite long time since the BFI_COUNTER is expected to be 0 given the serving beam (s) were working when the UE had previously SCG active (and even if they wouldn’ t, it is expected the beamFailureDetectionTimer would have expired during inactivity of the SCG) .

According to some conventional technologies, a prohibit timer can avoid frequent UE reporting, but can bring some risks especially when UE wants to leave RLM/BFD relaxation. For example, at this moment UE should report to network immediately as its signal quality is not stable and should not do relaxation anymore. However, if the prohibit timer is still running, the UE cannot report to the network that it needs to leave the RLM/BFD relaxation. Moreover, the good serving cell quality is not mandatory to be configured, which means the related parameters can be fixed for all UEs. Considering UEs reception sensitivity maybe different, unified parameters may not suitable.

In order to solve at least part of the above problems or other potential issues, solutions on UE report mechanism of RLM/BFD relaxation are needed. According to embodiments of the present disclosure, a network device transmits a configuration associated with a RLM/BFD relaxation to a terminal device. The terminal device determines whether criteria for the RLM/BFD relaxation are fulfilled. If the criteria for the RLM/BFD relaxation are fulfilled, the terminal device transmits a report indicating entering the RLM/BFD relaxation to the network device. If the criteria for the RLM/BFD relaxation are not fulfilled, the terminal device transmits the report indicating leaving the RLM/BFD relaxation to the network device. The terminal device performs the RLM/BFD relaxation after the transmission of the report which indicates entering the RLM/BFD relaxation. In this way, it is more flexible to report entering or leaving the RLM/BFD relaxation. Moreover, it can also save the number of bits in the report.

Fig. 1 illustrates a schematic diagram of a communication system in which embodiments of the present disclosure can be implemented. The communication system 100, which is a part of a communication network, comprises a terminal device 110-1, a terminal device 110-2, ..., a terminal device 110-N, which can be collectively referred to as “terminal device (s) 110. ” The number N can be any suitable integer number.

The communication system 100 further comprises a network device. In the communication system 100, the network device 120 and the terminal devices 110 can communicate data and control information to each other. The numbers of terminal devices shown in Fig. 1 are given for the purpose of illustration without suggesting any limitations.

Communications in the communication system 100 may be implemented according to any proper communication protocol (s) , comprising, but not limited to, cellular communication protocols of the first generation (1G) , the second generation (2G) , the third generation (3G) , the fourth generation (4G) and the fifth generation (5G) and on the like, wireless local network communication protocols such as Institute for Electrical and Electronics Engineers (IEEE) 802.11 and the like, and/or any other protocols currently known or to be developed in the future. Moreover, the communication may utilize any proper wireless communication technology, comprising but not limited to: Code Divided Multiple Address (CDMA) , Frequency Divided Multiple Address (FDMA) , Time Divided Multiple Address (TDMA) , Frequency Divided Duplexer (FDD) , Time Divided Duplexer (TDD) , Multiple-Input Multiple-Output (MIMO) , Orthogonal Frequency Divided Multiple Access (OFDMA) and/or any other technologies currently known or to be developed in the future.

Embodiments of the present disclosure can be applied to any suitable scenarios. For example, embodiments of the present disclosure can be implemented at reduced capability NR devices. Alternatively, embodiments of the present disclosure can be implemented in one of the followings: NR multiple-input and multiple-output (MIMO) , NR sidelink enhancements, NR systems with frequency above 52.6GHz, an extending NR operation up to 71GHz, narrow band-Internet of Thing (NB-IOT) /enhanced Machine Type Communication (eMTC) over non-terrestrial networks (NTN) , NTN, UE power saving enhancements, NR coverage enhancement, NB-IoT and LTE-MTC, Integrated Access and Backhaul (IAB) , NR Multicast and Broadcast Services, or enhancements on Multi-Radio Dual-Connectivity.

The term “slot” used herein refers to a dynamic scheduling unit. One slot comprises a predetermined number of symbols. The term “downlink (DL) sub-slot” may refer to a virtual sub-slot constructed based on uplink (UL) sub-slot. The DL sub-slot may comprise fewer symbols than one DL slot. The slot used herein may refer to a normal slot which comprises a predetermined number of symbols and also refer to a sub-slot which comprises fewer symbols than the predetermined number of symbols.

Embodiments of the present disclosure will be described in detail below. Reference is first made to Fig. 2, which shows a signaling chart illustrating process 200 between the terminal device and the network device according to some example embodiments of the present disclosure. Only for the purpose of discussion, the process 200 will be described with reference to Fig. 1. The process 200 may involve the terminal device 110-1 and the network device 120 in Fig. 1.

The network device 120 transmits 2010 a configuration associated with a RLM/BFD relaxation to the terminal device 110-1. In some embodiments, the network device 120 may transmit (2010) a RRC configuration enabling the RLM/BFD relaxation. Alternatively, the network device 120 may transmit (2010) a measurement configuration indicating a RLM/BFD relaxation report type. The term “RLM/BFD relaxation” used herein can refer to a mode where the terminal device uses less monitoring occasions in time domain for the RLM or BFD monitoring. For example, as shown in Fig. 3A, if the terminal device 110-1 is in a regular monitoring mode, the terminal device 110-1 may perform the RLM/BFD monitoring on the monitoring occasions 310-1, 310-2, 310-3, 310-4, 310-5, 310-6, 310-7, 310-8, 310-9 and 310-10. As shown in Fig. 3B, if the terminal device 110-1 is in a RLM/BFD relaxation mode, the terminal device 110-1 may perform the RLM/BFD monitoring on the monitoring occasions 310-1, 310-2, 310-3, 310-4, 310-5, 310-9 and 310-10. In other words, the terminal device 110-1 does not perform the RLM/BFD monitoring on the monitoring occasions 310-6, 310-7 and 310-8. It should be noted that the numbers of monitoring occasions shown in Figs. 3A and 3B are only an example not limitation.

The terminal device 110-1 determines 2020 whether criteria for the RLM/BFD relaxation are fulfilled or not. In some embodiments, the criteria may indicate a low mobility. In this case, the terminal device 110-1 may perform reference signal received power (RSRP) measurements and determine whether criteria are fulfilled based on the RSRS measurements. For example, the relaxed measurement criterion for UE with low mobility is fulfilled if a difference between Srxlev _Ref and Srxlev is smaller than S _SearchDeltaP within a duration represented as T _SearchDeltaP (i.e., (Srxlev _Ref –Srxlev) < S _SearchDeltaP within T _SearchDeltaP) , where Srxlev represents a current Srxlev value of the serving cell and Srxlev _Ref represents a reference Srxlev value of the serving cell. The Srxlev value can be determined based on a measurement RSRP level and a minimum RSRP level for camping, such as, Srxlev = Qrxlevmeas -qRxLevMin, where Qrxlevemeas represents the measured RSRP level and qRxLevMin represents minimum RSRP level for camping.

In addition, the criteria may indicate a good serving cell quality. In this case, if a radio link quality measured by the terminal device 110-1 exceeds a threshold quality, the terminal device 110-1 can determine that the relaxed measurement criterion for good serving cell quality is fulfilled. For example, when Radio link quality > Qx + Offset (dB) , the terminal device 110-1 can determine that the serving cell has a good serving cell quality, where Qx represents the threshold quality and Offset represents an quality offset. In some embodiments, the parameters (for example, the threshold quality and the quality offset) associated with the good serving cell quality can be configured by the network device 120. Alternatively, such parameters can be predefined at the terminal device 110-1. It should be noted that the criteria for the RLM/BFD relaxation may other parameters.

If the criteria are fulfilled, the terminal device 110-1 transmits 2030 a report to the network device 120. In this case, the report indicates entering the RLM/BFD relaxation. That is, if the report indicates entering the RLM/BFD relaxation, it means that the criteria are fulfilled. The network device 120 may know that the criteria are fulfilled when the report indicates entering the RLM/BFD relaxation. In this way, the network can still know UE’s relaxation state in real time, even there is not network relaxation indication introduced. In some embodiments, the report may be transmitted in UE assistance information. Alternatively, the report may be transmitted in the measurement report.

In some embodiments, a prohibit timer may be used. In this case, in some embodiments, if the prohibit timer is not running, the report can be transmitted to the network device. Alternatively, if the prohibit timer is disabled, the report can be transmitted to the network device. In this way, it avoids frequently transmitting the RLM/BFD reports. In some embodiments, the terminal device 110-1 may transmit the report while starting the prohibit timer. In other words, the transmission of the report and starting the prohibit timer can be simultaneous.

The terminal device 110-1 performs 2040 the RLM/BFD relaxation after the transmission of the report. Referring to Fig. 3B, as mentioned above, the terminal device 110-1 may perform the RLM/BFD monitoring on the monitoring occasions 310-1, 310-2, 310-3, 310-4, 310-5, 310-9 and 310-10 and does not perform the RLM/BFD monitoring on the monitoring occasions 310-6, 310-7 and 310-8.

If the criteria are not fulfilled, the terminal device 110-1 can perform a normal RLM/BFD. For example, referring to Fig. 3A, the terminal device 110-1 may perform the RLM/BFD monitoring on the monitoring occasions 310-1, 310-2, 310-3, 310-4, 310-5, 310-6, 310-7, 310-8, 310-9 and 310-10.

In some embodiments, after entering the RLM/BFD relaxation, the terminal device 110-1 may further determine 2050 whether criteria for the RLM/BFD relaxation are still fulfilled or not. For example, if the terminal device 110-1 is still in low mobility and has a good serving cell quality, the criteria for the RLM/BFD relaxation are still fulfilled. In this case, the terminal device 110-1 can continue performing the RLM/BFD relaxation. Alternatively, if the terminal device 110-1 is not in low mobility and/or does not have a good serving cell quality, the criteria for the RLM/BFD relaxation are not fulfilled any more. In this case, the terminal device 110-1 can leave 2060 the RLM/BFD relaxation. The terminal device 110-1 may transmit a report indicating leaving the RLM/BFD relaxation. That is, if the report indicates leaving the RLM/BFD relaxation, it means that the criteria are unfulfilled. The network device 120 may know that the criteria are unfulfilled when the report indicates leaving the RLM/BFD relaxation.

In some embodiments, if the prohibit timer is used, the report indicating leaving the RLM/BFD relaxation can be transmitted to the network device 120, regardless whether the prohibit timer is running. Alternatively, if the prohibit timer is set to a predetermined value (for example, 0) , the report indicating leaving the RLM/BFD relaxation can be transmitted to the network device 120. In some other embodiments, if the prohibit timer is disabled, the report indicating leaving the RLM/BFD relaxation can be transmitted to the network device 120. In this way, it ensures that the terminal device can exit the RLM/BFD relaxation immediately when the terminal device detects its signal is no longer stable, thereby avoiding radio link failure (RLF) and beam failure recovery (BFR) . In some embodiments, the terminal device 110-1 may transmit the report while restarting or staring the prohibit timer. In other words, the transmission of the report and restarting or starting the prohibit timer can be simultaneous.

Fig. 4 shows a signaling chart illustrating process 400 between the terminal device and the network device according to some example embodiments of the present disclosure, where the report is transmitted in UE assistance information (UAI) . Only for the purpose of discussion, the process 400 will be described with reference to Fig. 1. The process 400 may involve the terminal device 110-1 and the network device 120 in Fig. 1. It should be noted that embodiments shown in Fig. 4 are only examples not limitations.

The network device 120 may transmit 4010 a RRC configuration enabling the RLM/BFD relaxation. The terminal device 110-1 may determine 4020 whether criteria for the RLM/BFD relaxation is fulfilled or not. In some embodiments, the criteria may indicate a low mobility. In addition, the criteria may indicate a good serving cell quality.

If the criteria are fulfilled, the terminal device 110-1 may transmit 4031 UE assistance information to the network device 120. In this case, the UE assistance information indicates entering the RLM/BFD relaxation. That is, if the UE assistance information indicates entering the RLM/BFD relaxation, it means that the criteria are fulfilled. The network device 120 may know that the criteria are fulfilled when the UE assistance information indicates entering the RLM/BFD relaxation. In this way, the network can still know UE’s relaxation state in real time, even there is not network relaxation indication introduced. In some embodiments, if the first prohibit timer is not running, the UE assistance information can be transmitted (4031) to the network device. Alternatively, if the first prohibit timer is disabled, the UE assistance information can be transmitted (4031) to the network device. In this way, it avoids frequently transmitting the RLM/BFD reports. In some embodiments, the terminal device 110-1 may transmit 4031 the UE assistance information while starting 4050 the first prohibit timer. In other words, the transmission of the UE assistance information and starting the first prohibit timer can be simultaneous. If the criteria are fulfilled, the terminal device 110-1 may perform 4041 the RLM/BFD relaxation after the transmission of the UE assistance information.

If the criteria are not fulfilled any more, the terminal device 110-1 may leave 4032 the RLM/BFD relaxation. The terminal device 110-1 may transmit 4042 the UE assistance information indicating leaving the RLM/BFD relaxation. That is, if the UE assistance information indicates leaving the RLM/BFD relaxation, it means that the criteria are unfulfilled. The network device 120 may know that the criteria are unfulfilled when the UE assistance information indicates leaving the RLM/BFD relaxation. In this way, it ensures that the terminal device can exit the RLM/BFD relaxation immediately when the terminal device detects its signal is no longer stable, thereby avoiding radio link failure (RLF) and beam failure recovery (BFR) . In some embodiments, if the first prohibit timer is used, the UE assistance information indicating leaving the RLM/BFD relaxation can be transmitted to the network device 120, regardless whether the first prohibit timer is running. Alternatively, if the first prohibit timer is set to a predetermined value (for example, 0) , the UE assistance information indicating leaving the RLM/BFD relaxation can be transmitted to the network device 120. In some other embodiments, if the first prohibit timer is disabled, the UE assistance information indicating leaving the RLM/BFD relaxation can be transmitted to the network device 120. In this way, it ensures that the terminal device can exit the RLM/BFD relaxation immediately when the terminal device detects its signal is no longer stable, thereby avoiding radio link failure (RLF) and beam failure recovery (BFR) . In some embodiments, the terminal device 110-1 may transmit the UE assistance information while restarting or staring the first prohibit timer. In other words, the transmission of the UE assistance information and restarting or starting the first prohibit timer can be simultaneous.

In some embodiments, the UE assistance information may also comprise other UE preference parameters. In this way, when the relaxation related parameters are predefined, it may not be efficient for all kinds of UE, UE capable of RLM/BFD relaxation can provide preferred parameters to better fit this feature. In some embodiments, the UE assistance information may comprise a preference signal quality threshold for the criteria. Alternatively or in addition, the UE assistance information may comprise a preference signal quality offset for the criteria. In some other embodiments, the UE assistance information may also comprise a preference relaxation factor. The preference relaxation factor can be used to control the RLM/BFD relaxation level. The value of relaxation factor (K) can be any proper integer, for example, 1, 2, 3, 4 and the like. For example, if the value of relaxation factor is 1, it means that the terminal device 110-1 can perform normal RLM/BFD monitoring. If the value of relaxation factor is 2, it means that the current period for evaluating (T_evaluate) and/or the current period for reporting (T_indicate) (both for RLM/BFD monitoring) can be double (i.e. the relaxation period is T*K ) . The UE assistance information may further comprise one or more of: a first maximum number of consecutive out-of-synchronization indications (N310) , a second maximum number of consecutive in-synchronization indications (N311) , a timer for receiving the first maximum number of consecutive out-of-synchronization indications (T310) , a preference beam failure instance maximum count (BeamFailureInstanceMaxCount) , or a preference beam failure detection timer (BeamFailureDetectionTimer) . The term “N310” used herein can refer to a maximum number of consecutive "out-of-sync" (OOS) indications for the SpCell received from lower layers. The term “N311” used herein can refer to a maximum number of consecutive "in-sync" indications for the SpCell received from lower layers. The term “T310” used herein can refer to a timer start upon receiving consecutive N310 OOS, RLF happen when expired. The term “beamFailureInstanceMaxCount” used herein can refer a count that determines after how many beam failure events the UE triggers beam failure recovery. The term “beamFailureDetectionTimer” used herein can refer to a timer for beam failure detection.

Table 1 below shows an example of the UE assistance information. It should be noted Table 1 is only an example not limitation.

Table 1

In some embodiments, the UE assistance information indicating entering or leaving the RLM/BFD and the UE assistance information comprising UE preference parameters can be transmitted together. Alternatively, the UE assistance information indicating entering or leaving the RLM/BFD and the UE assistance information comprising UE preference parameters can be transmitted separately.

In some embodiments, the terminal device 110-1 may transmit the UE assistance information comprising UE preference parameters without considering a second prohibit timer. For example, if the UE preference parameters are not transmitted previously, the terminal device 110-1 may directly transmit the UE assistance information comprising UE preference parameters. Alternatively, if the second prohibit timer is not running, the terminal device 110-1 may transmit the UE assistance information comprising UE preference parameters. For example, if the current UE preference parameters are different from the previous UE preference parameters, the terminal device 110-1 may transmit the UE assistance information comprising UE preference parameters when the second prohibit timer is not running. In some embodiments, the second prohibit timer may be the same as the first prohibit timer. Alternatively, the second prohibit timer may be different from the first prohibit timer.

Table 2 below shows an example description of the process 400 where the prohibit timer is used. Table 3 below shows an example description of the process 400 where the prohibit timer is not used.

Table 2

Table 3

Fig. 5 shows a signaling chart illustrating process 500 between the terminal device and the network device according to some example embodiments of the present disclosure, where the report is transmitted in the measurement report. Only for the purpose of discussion, the process 500 will be described with reference to Fig. 1. The process 500 may involve the terminal device 110-1 and the network device 120 in Fig. 1. It should be noted that embodiments shown in Fig. 5 are only examples not limitations.

The network device may transmit 5010 a measurement configuration indicating the RLM/BFD relaxation. For example, a report type “reportRLM/BFD-Relaxation” can be introduced into ReportConfig. Table 4 below shows an example of the measurement configuration. It should be noted that Table 4 is only an example not limitation.

Table 4

The terminal device 110-1 may determine 5020 whether criteria for the RLM/BFD relaxation is fulfilled or not. In some embodiments, the criteria may indicate a low mobility. In addition, the criteria may indicate a good serving cell quality.

If the criteria are fulfilled, the terminal device 110-1 may transmit 5031 measurement report to the network device 120. In this case, the measurement report information indicates entering the RLM/BFD relaxation. That is, if the measurement report indicates entering the RLM/BFD relaxation, it means that the criteria are fulfilled. The network device 120 may know that the criteria are fulfilled when the measurement report indicates entering the RLM/BFD relaxation. In this way, the network can still know UE’s relaxation state in real time, even there is not network relaxation indication introduced. If the criteria are fulfilled, the terminal device 110-1 may perform 4041 the RLM/BFD relaxation after the transmission of the UE assistance information.

If the criteria are not fulfilled any more, the terminal device 110-1 may leave 5032 the RLM/BFD relaxation. The terminal device 110-1 may transmit 5042 the measurement report indicating leaving the RLM/BFD relaxation. That is, if the measurement report indicates leaving the RLM/BFD relaxation, it means that the criteria are unfulfilled. The network device 120 may know that the criteria are unfulfilled when the measurement report indicates leaving the RLM/BFD relaxation. In this way, it ensures that the terminal device can exit the RLM/BFD relaxation immediately when the terminal device detects its signal is no longer stable, thereby avoiding radio link failure (RLF) and beam failure recovery (BFR) .

In some embodiments, the “enterRelaxation” information element (IE) and “leaveRelaxtion” IE can be introduced into “MeasResults” within the measurement report. In this case, if the criteria are fulfilled, the measurement report can comprise an enter relaxation IE. If the criteria are unfulfilled, the measurement report can comprise a leave relaxation IE. Table 5 shows an example of the measurement report. It should be noted that Table 5 is only an example not limitation.

Table 5

Table 6 below shows an example embodiment where the “enterRelaxation” IE and “leaveRelaxtion” IE can be introduced into “MeasResults” within the measurement report.

Table 6

Alternatively, the “relaxationIndication” IE can be introduced into MeasResults within the measurement report. In this case, if the criteria are fulfilled, the measurement report can comprise the relaxation indication information element with a first predetermined value. If the criteria are unfulfilled, the measurement report can comprise the relaxation indication information element with a second predetermined value. Table 7 shows an example of the measurement report. It should be noted that Table 7 is only an example not limitation.

Table 7

Table 8 below shows an example embodiment where the “relaxationIndication” IE can be introduced into “MeasResults” within the measurement report.

Table 8

In some embodiments, a prohibit timer may be used. In this case, the measurement configuration received (5010) from the network device may indicate the prohibit timer. Table 9 below shows an example of the measurement configuration where the prohibit timer is introduced into the measurement configuration. It should be Table 9 is only an example not limitation.

Table 9

In some embodiments, if the prohibit timer is not running, the measurement report can be transmitted (5031) to the network device. Alternatively, if the prohibit timer is disabled, the measurement report can be transmitted (5031) to the network device. In this way, it avoids frequently transmitting the RLM/BFD reports. In some embodiments, the terminal device 110-1 may transmit (5031) the measurement report while starting 5050 the prohibit timer. In other words, the measurement report and starting the first prohibit timer can be simultaneous. If the criteria are fulfilled, the terminal device 110-1 may perform 5041 the RLM/BFD relaxation after the transmission of the measurement report.

In some embodiments, if the prohibit timer is used, the measurement report indicating leaving the RLM/BFD relaxation can be transmitted to the network device 120, regardless whether the prohibit timer is running. Alternatively, if the prohibit timer is set to a predetermined value (for example, 0) , the measurement report indicating leaving the RLM/BFD relaxation can be transmitted to the network device 120. In some other embodiments, if the prohibit timer is disabled, the measurement report indicating leaving the RLM/BFD relaxation can be transmitted to the network device 120. In this way, it ensures that the terminal device can exit the RLM/BFD relaxation immediately when the terminal device detects its signal is no longer stable, thereby avoiding radio link failure (RLF) and beam failure recovery (BFR) . In some embodiments, the terminal device 110-1 may transmit the measurement report while restarting or staring the first prohibit timer. In other words, the transmission of the measurement report and starting or restarting the first prohibit timer can be simultaneous.

Table 10 below shows an example description of the process 500 where the prohibit timer is used. Table 11 below shows an example description of the process 500 where the prohibit timer is not used.

Table 10

Table 11

Fig. 6 shows a flowchart of an example method 600 in accordance with an embodiment of the present disclosure. The method 600 can be implemented at any suitable devices. Only for the purpose of illustrations, the method 600 can be implemented at a terminal device 110-1 as shown in Fig. 1.

At block 610, the terminal device 110-1 receives a configuration associated with a RLM/BFD relaxation from the network device 120. In some embodiments, the configuration associated with a RLM/BFD relaxation may be a RRC configuration enabling the RLM/BFD relaxation. Alternatively, the configuration associated with a RLM/BFD relaxation may be a measurement configuration indicating a RLM/BFD relaxation report type.

At block 620, the terminal device 110-1 determines whether criteria for the RLM/BFD relaxation are fulfilled or not. In some embodiments, the criteria may indicate a low mobility. In this case, the terminal device 110-1 may perform reference signal received power (RSRP) measurements and determine whether criteria are fulfilled based on the RSRS measurements. For example, the relaxed measurement criterion for UE with low mobility is fulfilled if a difference between Srxlev _Ref and Srxlev is smaller than S _SearchDeltaP within a duration represented as T _SearchDeltaP (i.e., (Srxlev _Ref –Srxlev) <S _SearchDeltaP within T _SearchDeltaP) , where Srxlev represents a current Srxlev value of the serving cell and Srxlev _Ref represents a reference Srxlev value of the serving cell. The Srxlev value can be determined based on a measurement RSRP level and a minimum RSRP level for camping, such as, Srxlev = Qrxlevmeas -qRxLevMin, where Qrxlevemeas represents the measured RSRP level and qRxLevMin represents minimum RSRP level for camping.

At block 630, if the criteria are fulfilled, the terminal device 110-1 transmits a report to the network device 120. In this case, the report indicates entering the RLM/BFD relaxation. That is, if the report indicates entering the RLM/BFD relaxation, it means that the criteria are fulfilled. The network device 120 may know that the criteria are fulfilled when the report indicates entering the RLM/BFD relaxation. In this way, the network can still know UE’s relaxation state in real time, even there is not network relaxation indication introduced. In some embodiments, the report may be transmitted in UE assistance information. Alternatively, the report may be transmitted in the measurement report.

At block 640, the terminal device 110-1 performs the RLM/BFD relaxation after the transmission of the report. If the criteria are not fulfilled, the terminal device 110-1 can perform a normal RLM/BFD regardless of the transmission of the report.

In some embodiments, after entering the RLM/BFD relaxation, the terminal device 110-1 may further determine whether criteria for the RLM/BFD relaxation are still fulfilled or not. For example, if the terminal device 110-1 is still in low mobility and has a good serving cell quality, the criteria for the RLM/BFD relaxation are still fulfilled. In this case, the terminal device 110-1 can continue performing the RLM/BFD relaxation. Alternatively, if the terminal device 110-1 is not in low mobility and/or does not have a good serving cell quality, the criteria for the RLM/BFD relaxation are not fulfilled any more. In this case, the terminal device 110-1 can leave the RLM/BFD relaxation. The terminal device 110-1 may transmit a report indicating leaving the RLM/BFD relaxation. That is, if the report indicates leaving the RLM/BFD relaxation, it means that the criteria are unfulfilled. The network device 120 may know that the criteria are unfulfilled when the report indicates leaving the RLM/BFD relaxation.

In some embodiments, if the prohibit timer is used, the report indicating leaving the RLM/BFD relaxation can be transmitted to the network device 120, regardless whether the prohibit timer is running. Alternatively, if the prohibit timer is set to a predetermined value (for example, 0) , the report indicating leaving the RLM/BFD relaxation can be transmitted to the network device 120. In some other embodiments, if the prohibit timer is disabled, the report indicating leaving the RLM/BFD relaxation can be transmitted to the network device 120. In this way, it ensures that the terminal device can exit the RLM/BFD relaxation immediately when the terminal device detects its signal is no longer stable, thereby avoiding radio link failure (RLF) and beam failure recovery (BFR) . In some embodiments, the terminal device 110-1 may transmit the report while restarting or staring the prohibit timer. In other words, the transmission of the report and restarting the prohibit timer can be simultaneous.

Fig. 7 shows a flowchart of an example method 700 in accordance with an embodiment of the present disclosure. The method 700 can be implemented at any suitable devices. Only for the purpose of illustrations, the method 700 can be implemented at a network device 120 as shown in Fig. 1.

At block 710, the network device 120 transmits a configuration associated with a RLM/BFD relaxation to the terminal device 110-1. In some embodiments, the network device 120 may transmit a RRC configuration enabling the RLM/BFD relaxation. Alternatively, the network device 120 may transmit a measurement configuration indicating a RLM/BFD relaxation report type.

At block 710, the network device 120 receives a report associated with the RLM/BFD relaxation from the terminal device 110-1. In some embodiments, the report may be transmitted in UE assistance information. Alternatively, the report may be transmitted in the measurement report.

If the criteria are fulfilled, the report indicates entering the RLM/BFD relaxation. That is, if the report indicates entering the RLM/BFD relaxation, it means that the criteria are fulfilled. The network device 120 may know that the criteria are fulfilled when the report indicates entering the RLM/BFD relaxation. In this way, the network can still know UE’s relaxation state in real time, even there is not network relaxation indication introduced.

In some embodiments, if the criteria for the RLM/BFD relaxation are not fulfilled any more, the network device may receive a report indicating leaving the RLM/BFD relaxation. That is, if the report indicates leaving the RLM/BFD relaxation, it means that the criteria are unfulfilled. The network device 120 may know that the criteria are unfulfilled when the report indicates leaving the RLM/BFD relaxation.

In some embodiments, the UE assistance information may also comprise other UE preference parameters. In this way, when the relaxation related parameters are predefined, it may not be efficient for all kinds of UE, UE capable of RLM/BFD relaxation can provide preferred parameters to better fit this feature. In some embodiments, the UE assistance information may comprise a preference signal quality threshold for the criteria. Alternatively or in addition, the UE assistance information may comprise a preference signal quality offset for the criteria. In some other embodiments, the UE assistance information may also comprise a preference relaxation factor. The preference relaxation factor can be used to control the RLM/BFD relaxation. For example, when the relaxation factor is less than one it is said to be under relaxed and it is called over relaxed when the relaxation factor is more than one. The UE assistance information may further comprise one or more of: a first maximum number of consecutive out-of-synchronization indications (N310) , a second maximum number of consecutive in-synchronization indications (N311) , a timer for receiving the first maximum number of consecutive out-of-synchronization indications (T310) , a preference beam failure instance maximum count (BeamFailureInstanceMaxCount) , or a preference beam failure detection timer (BeamFailureDetectionTimer) .

It should be noted that embodiments described with reference to Figs. 2-7 can be implemented together or separately.

In some embodiments, a terminal device comprises circuitry configured to perform receiving, from a network device, a configuration associated with a radio link monitoring/beam failure detection (RLM/BFD) relaxation; determining whether criteria for the RLM/BFD relaxation are fulfilled; in accordance with a determination that the criteria for the RLM/BFD relaxation are fulfilled, transmitting, to the network device, a report indicating entering the RLM/BFD relaxation; and performing the RLM/BFD relaxation after the transmission of the report.

In some embodiments, the terminal device comprises circuitry configured to perform: leaving the RLM/BFD relaxation upon the criteria for the RLM/BFD relaxation being unfulfilled.

In some embodiments, the terminal device comprises circuitry configured to perform receiving the configuration associated with the RLM/BFD relaxation by: receiving, from the network device, a radio resource control (RRC) configuration enabling the RLM/BFD relaxation.

In some embodiments, the terminal device comprises circuitry configured to perform transmitting the report indicating entering the RLM/BFD relaxation by: in accordance with a determination that the criteria for the RLM/BFD relaxation are fulfilled and a determination that a first timer is disabled or not running, transmitting, to the network device, user equipment (UE) assistance information, wherein the UE assistance information comprises an information element indicating entering the RLM/BFD relaxation.

In some embodiments, the terminal device comprises circuitry configured to perform starting the first timer upon the transmission of the UE assistance information.

In some embodiments, the terminal device comprises circuitry configured to perform in accordance with a determination that the criteria for the RLM/BFD relaxation are unfulfilled, transmitting, to the network device, UE assistance information, wherein the UE assistance information comprises an information element indicating leaving the RLM/BFD relaxation.

In some embodiments, the terminal device comprises circuitry configured to perform transmitting the UE assistance information by: transmitting the UE assistance information to the network device, regardless whether a first timer is running, or in accordance with a determination that the first timer is set to a predetermined value or a determination that the first timer is disabled.

In some embodiments, the terminal device comprises circuitry configured to perform starting or restarting the first timer upon the transmission of the UE assistance information.

In some embodiments, the terminal device comprises circuitry configured to perform transmitting, to the network device, UE assistance information indicating at least one of: a preference signal quality threshold for the criteria, a preference signal quality offset for the criteria, a preference relaxation factor, a first maximum number of consecutive out-of-synchronization indications, a second maximum number of consecutive in-synchronization indications, a timer for receiving the first maximum number of consecutive out-of-synchronization indications, a preference beam failure instance maximum count, or a preference beam failure detection timer.

In some embodiments, the terminal device comprises circuitry configured to perform transmitting the UE assistance information by in accordance with a determination that a second timer is not running, transmitting the UE assistance information to the network device.

In some embodiments, the terminal device comprises circuitry configured to perform receiving the configuration associated with the RLM/BFD relaxation by: receiving, from the network device, a measurement configuration indicating a RLM/BFD relaxation report type.

In some embodiments, the terminal device comprises circuitry configured to perform transmitting the report indicating entering the RLM/BFD relaxation by: in accordance with a determination that the criteria for the RLM/BFD relaxation are fulfilled, transmitting, to the network device, a measurement report, wherein the measurement report comprises an information element indicating entering the RLM/BFD relaxation.

In some embodiments, the information element is an enter relaxation information element, or the information element is a relaxation indication information element with a first predetermined value.

In some embodiments, the measurement configuration further indicates a third timer, and the terminal device comprises circuitry configured to perform in accordance with a determination that the third timer is disabled or not running, transmitting the measurement report to the network device while starting the third timer.

In some embodiments, the terminal device comprises circuitry configured to perform in accordance with a determination that the criteria for the RLM/BFD relaxation are unfulfilled, transmitting, to the network device, a measurement report, wherein the measurement report comprises an information element indicating leaving the RLM/BFD relaxation.

In some embodiments, the information element is a leave relaxation information element, or the information element is a relaxation indication information element with a second predetermined value.

In some embodiments, the measurement configuration further indicates a third timer. In some embodiments, the terminal device comprises circuitry configured to perform transmitting the measurement report further by: transmitting the measurement report to the network device, regardless whether the third timer is running, or in accordance with a determination that the third timer is set to a predetermined value or a determination that the third timer is disabled while starting or restarting the third timer.

In some embodiments, a network device comprises circuitry configured to perform transmitting, to a terminal device, a configuration associated with a radio link monitoring/beam failure detection (RLM/BFD) relaxation; and receiving, from the terminal device, a report associated with the RLM/BFD relaxation.

In some embodiments, the network device comprises circuitry configured to perform transmitting the configuration associated with the RLM/BFD relaxation by: transmitting, to the terminal device, a radio resource control (RRC) configuration enabling the RLM/BFD relaxation.

In some embodiments, the network device comprises circuitry configured to perform receiving the report associated with the RLM/BFD relaxation by: receiving, from the terminal device, user equipment (UE) assistance information, wherein the UE assistance information comprises an information element indicating entering the RLM/BFD relaxation.

In some embodiments, the network device comprises circuitry configured to perform receiving, from the terminal device, UE assistance information, wherein the UE assistance information comprises an information element indicating leaving the RLM/BFD relaxation.

In some embodiments, the network device comprises circuitry configured to perform receiving, from the terminal device, UE assistance information indicating at least one of: a preference signal quality threshold for the criteria, a preference signal quality offset for the criteria, a preference relaxation factor, a first maximum number of consecutive out-of-synchronization indications, a second maximum number of consecutive in-synchronization indications, a timer for receiving the first maximum number of consecutive out-of-synchronization indications, a preference beam failure instance maximum count, or a preference beam failure detection timer.

In some embodiments, the network device comprises circuitry configured to perform transmitting the configuration associated with the RLM/BFD relaxation by: transmitting, to the terminal device, a measurement configuration indicating a RLM/BFD relaxation report type.

In some embodiments, the network device comprises circuitry configured to perform receiving the report associated with the RLM/BFD relaxation by: receiving, from the terminal device, a measurement report, wherein the measurement report comprises an information element indicating entering the RLM/BFD relaxation.

In some embodiments, the network device comprises circuitry configured to perform receiving, from the terminal device, a measurement report, wherein the measurement report comprises an information element indicating leaving the RLM/BFD relaxation.

Fig. 8 is a simplified block diagram of a device 800 that is suitable for implementing embodiments of the present disclosure. The device 800 can be considered as a further example implementation of the terminal device 110-1 or the network device 120 as shown in Fig. 1. Accordingly, the device 800 can be implemented at or as at least a part of the terminal device 110-1 or the network device 120.

As shown, the device 800 includes a processor 810, a memory 820 coupled to the processor 810, a suitable transmitter (TX) and receiver (RX) 840 coupled to the processor 810, and a communication interface coupled to the TX/RX 840. The memory 820 stores at least a part of a program 830. The TX/RX 840 is for bidirectional communications. The TX/RX 840 has at least one antenna to facilitate communication, though in practice an Access Node mentioned in this application may have several ones. The communication interface may represent any interface that is necessary for communication with other network elements, such as X2 interface for bidirectional communications between eNBs, S1 interface for communication between a Mobility Management Entity (MME) /Serving Gateway (S-GW) and the eNB, Un interface for communication between the eNB and a relay node (RN) , or Uu interface for communication between the eNB and a terminal device.

The program 830 is assumed to include program instructions that, when executed by the associated processor 810, enable the device 800 to operate in accordance with the embodiments of the present disclosure, as discussed herein with reference to Fig. 2 to 7. The embodiments herein may be implemented by computer software executable by the processor 810 of the device 800, or by hardware, or by a combination of software and hardware. The processor 810 may be configured to implement various embodiments of the present disclosure. Furthermore, a combination of the processor 810 and memory 820 may form processing means 850 adapted to implement various embodiments of the present disclosure.

The memory 820 may be of any type suitable to the local technical network and may be implemented using any suitable data storage technology, such as a non-transitory computer readable storage medium, semiconductor-based memory devices, magnetic memory devices and systems, optical memory devices and systems, fixed memory and removable memory, as non-limiting examples. While only one memory 820 is shown in the device 800, there may be several physically distinct memory modules in the device 800. The processor 810 may be of any type suitable to the local technical network, and may include one or more of general purpose computers, special purpose computers, microprocessors, digital signal processors (DSPs) and processors based on multicore processor architecture, as non-limiting examples. The device 800 may have multiple processors, such as an application specific integrated circuit chip that is slaved in time to a clock which synchronizes the main processor.

Generally, various embodiments of the present disclosure may be implemented in hardware or special purpose circuits, software, logic or any combination thereof. Some aspects may be implemented in hardware, while other aspects may be implemented in firmware or software which may be executed by a controller, microprocessor or other computing device. While various aspects of embodiments of the present disclosure are illustrated and described as block diagrams, flowcharts, or using some other pictorial representation, it will be appreciated that the blocks, apparatus, systems, techniques or methods described herein may be implemented in, as non-limiting examples, hardware, software, firmware, special purpose circuits or logic, general purpose hardware or controller or other computing devices, or some combination thereof.

The present disclosure also provides at least one computer program product tangibly stored on a non-transitory computer readable storage medium. The computer program product includes computer-executable instructions, such as those included in program modules, being executed in a device on a target real or virtual processor, to carry out the process or method as described above with reference to Figs. 2 to 7. Generally, program modules include routines, programs, libraries, objects, classes, components, data structures, or the like that perform particular tasks or implement particular abstract data types. The functionality of the program modules may be combined or split between program modules as desired in various embodiments. Machine-executable instructions for program modules may be executed within a local or distributed device. In a distributed device, program modules may be located in both local and remote storage media.

Program code for carrying out methods of the present disclosure may be written in any combination of one or more programming languages. These program codes may be provided to a processor or controller of a general purpose computer, special purpose computer, or other programmable data processing apparatus, such that the program codes, when executed by the processor or controller, cause the functions/operations specified in the flowcharts and/or block diagrams to be implemented. The program code may execute entirely on a machine, partly on the machine, as a stand-alone software package, partly on the machine and partly on a remote machine or entirely on the remote machine or server.

The above program code may be embodied on a machine readable medium, which may be any tangible medium that may contain, or store a program for use by or in connection with an instruction execution system, apparatus, or device. The machine readable medium may be a machine readable signal medium or a machine readable storage medium. A machine readable medium may include but not limited to an electronic, magnetic, optical, electromagnetic, infrared, or semiconductor system, apparatus, or device, or any suitable combination of the foregoing. More specific examples of the machine readable storage medium would include an electrical connection having one or more wires, a portable computer diskette, a hard disk, a random access memory (RAM) , a read-only memory (ROM) , an erasable programmable read-only memory (EPROM or Flash memory) , an optical fiber, a portable compact disc read-only memory (CD-ROM) , an optical storage device, a magnetic storage device, or any suitable combination of the foregoing.

Further, while operations are depicted in a particular order, this should not be understood as requiring that such operations be performed in the particular order shown or in sequential order, or that all illustrated operations be performed, to achieve desirable results. In certain circumstances, multitasking and parallel processing may be advantageous. Likewise, while several specific implementation details are contained in the above discussions, these should not be construed as limitations on the scope of the present disclosure, but rather as descriptions of features that may be specific to particular embodiments. Certain features that are described in the context of separate embodiments may also be implemented in combination in a single embodiment. Conversely, various features that are described in the context of a single embodiment may also be implemented in multiple embodiments separately or in any suitable sub-combination.

Although the present disclosure has been described in language specific to structural features and/or methodological acts, it is to be understood that the present disclosure defined in the appended claims is not necessarily limited to the specific features or acts described above. Rather, the specific features and acts described above are disclosed as example forms of implementing the claims.

As used herein, the term ‘terminal device’ refers to any device having wireless or wired communication capabilities. Examples of the terminal device include, but not limited to, user equipment (UE) , personal computers, desktops, mobile phones, cellular phones, smart phones, personal digital assistants (PDAs) , portable computers, tablets, wearable devices, internet of things (IoT) devices, Ultra-reliable and Low Latency Communications (URLLC) devices, Internet of Everything (IoE) devices, machine type communication (MTC) devices, device on vehicle for V2X communication where X means pedestrian, vehicle, or infrastructure/network, devices for Integrated Access and Backhaul (IAB) , Small Data Transmission (SDT) , mobility, Multicast and Broadcast Services (MBS) , positioning, dynamic/flexible duplex in commercial networks, reduced capability (RedCap) , Space borne vehicles or Air borne vehicles in Non-terrestrial networks (NTN) including Satellites and High Altitude Platforms (HAPs) encompassing Unmanned Aircraft Systems (UAS) , eXtended Reality (XR) devices including different types of realities such as Augmented Reality (AR) , Mixed Reality (MR) and Virtual Reality (VR) , the unmanned aerial vehicle (UAV) commonly known as a drone which is an aircraft without any human pilot, devices on high speed train (HST) , or image capture devices such as digital cameras, sensors, gaming devices, music storage and playback appliances, or Internet appliances enabling wireless or wired Internet access and browsing and the like. The ‘terminal device’ can further has ‘multicast/broadcast’ feature, to support public safety and mission critical, V2X applications, transparent IPv4/IPv6 multicast delivery, IPTV, smart TV, radio services, software delivery over wireless, group communications and IoT applications. It may also incorporated one or multiple Subscriber Identity Module (SIM) as known as Multi-SIM. The term “terminal device” can be used interchangeably with a UE, a mobile station, a subscriber station, a mobile terminal, a user terminal or a wireless device.

The term “network device” refers to a device which is capable of providing or hosting a cell or coverage where terminal devices can communicate. Examples of a network device include, but not limited to, a Node B (NodeB or NB) , an evolved NodeB (eNodeB or eNB) , a next generation NodeB (gNB) , a transmission reception point (TRP) , a remote radio unit (RRU) , a radio head (RH) , a remote radio head (RRH) , an IAB node, a low power node such as a femto node, a pico node, a reconfigurable intelligent surface (RIS) , Network-controlled Repeaters, and the like.

The terminal or the network device may work on several frequency ranges, e.g. FR1 (410 MHz –7125 MHz) , FR2 (24.25GHz to 71GHz) , frequency band larger than 100GHz as well as Tera Hertz (THz) . It can further work on licensed/unlicensed/shared spectrum. The terminal device may have more than one connections with the network devices under Multi-Radio Dual Connectivity (MR-DC) application scenario. The terminal device or the network device can work on full duplex, flexible duplex and cross division duplex modes.

The network device may have the function of network energy saving, Self-Organising Networks (SON) /Minimization of Drive Tests (MDT) . The terminal may have the function of power saving.

The embodiments of the present disclosure may be performed in test equipment, e.g. signal generator, signal analyzer, spectrum analyzer, network analyzer, test terminal device, test network device, channel emulator.

The embodiments of the present disclosure may be performed according to any generation communication protocols either currently known or to be developed in the future. Examples of the communication protocols include, but not limited to, the first generation (1G) , the second generation (2G) , 2.5G, 2.75G, the third generation (3G) , the fourth generation (4G) , 4.5G, the fifth generation (5G) communication protocols, 5.5G, 5G-Advanced networks, or the sixth generation (6G) networks.

Claims

A communication method, comprising:

receiving, at a terminal device and from a network device, a configuration associated with a radio link monitoring/beam failure detection (RLM/BFD) relaxation;

determining whether criteria for the RLM/BFD relaxation are fulfilled;

in accordance with a determination that the criteria for the RLM/BFD relaxation are fulfilled, transmitting, to the network device, a report indicating entering the RLM/BFD relaxation; and

performing the RLM/BFD relaxation after the transmission of the report.
The method of claim 1, further comprising:

leaving the RLM/BFD relaxation upon the criteria for the RLM/BFD relaxation being unfulfilled.
The method of claim 1, wherein receiving the configuration associated with the RLM/BFD relaxation comprises:

receiving, from the network device, a radio resource control (RRC) configuration enabling the RLM/BFD relaxation.
The method of claim 1, wherein transmitting the report indicating entering the RLM/BFD relaxation comprises:

in accordance with a determination that the criteria for the RLM/BFD relaxation are fulfilled and a determination that a first timer is disabled or not running, transmitting, to the network device, user equipment (UE) assistance information, wherein the UE assistance information comprises an information element indicating entering the RLM/BFD relaxation.
The method of claim 4, further comprising:

starting the first timer upon the transmission of the UE assistance information.
The method of claim 1, further comprising:

in accordance with a determination that the criteria for the RLM/BFD relaxation are unfulfilled, transmitting, to the network device, UE assistance information, wherein the UE assistance information comprises an information element indicating leaving the RLM/BFD relaxation.
The method of claim 6, wherein transmitting the UE assistance information comprises:

transmitting the UE assistance information to the network device, regardless whether a first timer is running, or in accordance with a determination that the first timer is set to a predetermined value or a determination that the first timer is disabled.
The method of claim 6, further comprising:

starting or restarting the first timer upon the transmission of the UE assistance information.
The method of claim 1, further comprising:

transmitting, to the network device, UE assistance information indicating at least one of:

a preference signal quality threshold for the criteria,

a preference signal quality offset for the criteria,

a preference relaxation factor,

a first maximum number of consecutive out-of-synchronization indications,

a second maximum number of consecutive in-synchronization indications,

a timer for receiving the first maximum number of consecutive out-of-synchronization indications,

a preference beam failure instance maximum count, or

a preference beam failure detection timer.
The method of claim 9, wherein transmitting the UE assistance information comprises:

in accordance with a determination that a second timer is not running, transmitting the UE assistance information to the network device.
The method of claim 1, wherein receiving the configuration associated with the RLM/BFD relaxation comprises:

receiving, from the network device, a measurement configuration indicating a RLM/BFD relaxation report type.
The method of claim 11, wherein transmitting the report indicating entering the RLM/BFD relaxation comprises:

in accordance with a determination that the criteria for the RLM/BFD relaxation are fulfilled, transmitting, to the network device, a measurement report, wherein the measurement report comprises an information element indicating entering the RLM/BFD relaxation.
The method of claim 12, wherein the information element is an enter relaxation information element, or

the information element is a relaxation indication information element with a first predetermined value.
The method of claim 12, wherein the measurement configuration further indicates a third timer, and

wherein transmitting the measurement report further comprises:

in accordance with a determination that the third timer is disabled or not running, transmitting the measurement report to the network device while starting the third timer.
The method of claim 11, further comprising:

in accordance with a determination that the criteria for the RLM/BFD relaxation are unfulfilled, transmitting, to the network device, a measurement report, wherein the measurement report comprises an information element indicating leaving the RLM/BFD relaxation.
The method of claim 15, wherein the information element is a leave relaxation information element, or

the information element is a relaxation indication information element with a second predetermined value.
The method of claim 15, wherein the measurement configuration further indicates a third timer, and

wherein transmitting the measurement report further comprises:

transmitting the measurement report to the network device, regardless whether the third timer is running, or in accordance with a determination that the third timer is set to a predetermined value or a determination that the third timer is disabled while starting or restarting the third timer.
A communication method, comprising:

transmitting, at a network device and to a terminal device, a configuration associated with a radio link monitoring/beam failure detection (RLM/BFD) relaxation; and

receiving, from the terminal device, a report associated with the RLM/BFD relaxation.
The method of claim 18, wherein transmitting the configuration associated with the RLM/BFD relaxation comprises:

transmitting, to the terminal device, a radio resource control (RRC) configuration enabling the RLM/BFD relaxation.
The method of claim 18, wherein receiving the report associated with the RLM/BFD relaxation comprises:

receiving, from the terminal device, user equipment (UE) assistance information, wherein the UE assistance information comprises an information element indicating entering the RLM/BFD relaxation.
The method of claim 18, further comprising:

receiving, from the terminal device, UE assistance information, wherein the UE assistance information comprises an information element indicating leaving the RLM/BFD relaxation.
The method of claim 18, further comprising:

receiving, from the terminal device, UE assistance information indicating at least one of:

a preference signal quality threshold for the criteria,

a preference signal quality offset for the criteria,

a preference relaxation factor,

a first maximum number of consecutive out-of-synchronization indications,

a second maximum number of consecutive in-synchronization indications,

a timer for receiving the first maximum number of consecutive out-of-synchronization indications,

a preference beam failure instance maximum count, or

a preference beam failure detection timer.
The method of claim 18, wherein transmitting the configuration associated with the RLM/BFD relaxation comprises:

transmitting, to the terminal device, a measurement configuration indicating a RLM/BFD relaxation report type.
The method of claim 23, wherein receiving the report associated with the RLM/BFD relaxation comprises:

receiving, from the terminal device, a measurement report, wherein the measurement report comprises an information element indicating entering the RLM/BFD relaxation.
The method of claim 24, wherein the information element is an enter relaxation information element, or

the information element is a relaxation indication information element with a first predetermined value.
The method of claim 18, further comprising:

receiving, from the terminal device, a measurement report, wherein the measurement report comprises an information element indicating leaving the RLM/BFD relaxation.
The method of claim 26, wherein the information element is a leave relaxation information element, or

the information element is a relaxation indication information element with a second predetermined value.
A terminal device comprising:

a processor; and

a memory coupled to the processor and storing instructions thereon, the instructions, when executed by the processor, causing the terminal device to perform acts comprising the method according to any of claims 1-17.
A network device comprising:

a processor; and

a memory coupled to the processor and storing instructions thereon, the instructions, when executed by the processor, causing the network device to perform acts comprising the method according to any of claims 18-27.
A computer readable medium having instructions stored thereon, the instructions, when executed on at least one processor, causing the at least one processor to perform the method according to any of claims 1-17 or any of claims 18-27.