Cache status reporting triggered by radio link failure in multi-path operation

Abstract

Systems, methods, apparatuses, and computer program products are provided for buffer status reporting triggered by radio link failure in scenarios involving user equipment multi-path operation. For example, a method may include communicating with a network over a plurality of paths, a respective path of the plurality of paths including a first radio link of a user equipment and a second radio link of the user equipment. The method may also include detecting or predicting a radio link failure of the first radio link. The method may also include triggering a cache status report to the network based on the detection or prediction of the radio link failure.

Description

Technical Field

[0001] Some example embodiments may generally relate to communications including mobile or wireless telecommunication systems, such as Long Term Evolution (LTE) or fifth generation (5G) radio access technology or new radio (NR) access technology, or other communications systems including subsequent generations of the same or similar standards. For example, certain example embodiments may generally relate to buffer status reporting triggered by a radio link failure in a scenario of multipath operation of a user equipment. Background Art

[0002] Examples of mobile or wireless telecommunication systems may include Universal Mobile Telecommunications System (UMTS) Terrestrial Radio Access Network (UTRAN), Long Term Evolution (LTE) Evolved UTRAN (E-UTRAN), Advanced LTE (LTE-A), MulteFire, LTE-A Pro, and / or fifth generation (5G) radio access technology or new radio (NR) access technology. 5G wireless systems refer to next generation (NG) radio systems and network architectures. 5G systems are primarily built on 5G New Radio (NR), but 5G (or NG) networks may also be built on E-UTRA radio. From Release 18 (Rel-18), 5G is referred to as Advanced 5G. It is estimated that NR provides bit rates in the order of 10-20 Gbit / s or higher, and may support at least service categories such as enhanced mobile broadband (eMBB) and ultra-reliable low latency communications (URLLC) and massive machine type communications (mMTC). NR is expected to deliver extreme broadband and ultra-robust, low latency connections and massive networking to support the Internet of Things (IoT). As IoT and machine-to-machine (M2M) communications become more prevalent, there will be an increasing demand for networks that meet low power, low data rate and long battery life requirements. The Next Generation Radio Access Network (NG-RAN) represents the RAN for 5G that can provide NR and LTE (and Advanced LTE) radio access. Note that in 5G, a node that can provide radio access functionality to user equipment (i.e., similar to a Node B, NB in ​​UTRAN or an evolved NB, eNB in ​​LTE) can be referred to as a Next Generation NB (gNB) when built on an NR radio, and can be referred to as a Next Generation eNB (NG-eNB) when built on an E-UTRA radio. 6G is currently under development and may replace 5G and Advanced 5G. Summary of the invention

[0003] An embodiment may be directed to a device. The device may include at least one processor and at least one memory storing instructions. When the instruction is executed by the at least one processor, the device may at least communicate with a network through multiple paths. The corresponding paths in the multiple paths may include: a first radio link of the device and a second radio link of the device. When the instruction is executed by the at least one processor, the device may at least detect or predict a radio link failure of the first radio link. When the instruction is executed by the at least one processor, the device may at least perform a detection or prediction of a radio link failure based on the detection or prediction of the radio link failure, and trigger a cache status report to the network.

[0004] Embodiments may be directed to a method. The method may include communicating with a network via multiple paths. A corresponding path in the multiple paths includes: a first radio link of a device and a second radio link of the device. The method may also include detecting or predicting a radio link failure of the first radio link. The method may also include triggering a cache status report to the network based on the detection or prediction of the radio link failure.

[0005] One embodiment may be directed to an apparatus. The apparatus may include components for communicating with a network via multiple paths. A corresponding path in the multiple paths includes a first radio link of the apparatus and a second radio link of the apparatus. The apparatus may also include components for detecting or predicting a radio link failure of the first radio link. The apparatus may also include components for triggering a cache status report to the network based on the detection or prediction of the radio link failure. BRIEF DESCRIPTION OF THE DRAWINGS

[0006] For a proper understanding of the example embodiments, reference should be made to the accompanying drawings, in which:

[0007] Figure 1A An example rule set is shown that provides an example implementation of certain embodiments;

[0008] Figure 1B Another example rule set providing an example implementation of certain embodiments is shown;

[0009] Figure 1C An example rule set is shown that provides an example implementation of certain embodiments;

[0010] Figure 2 Methods according to some embodiments are shown; and

[0011] Figure 3 An example block diagram of a system according to an embodiment is shown. DETAILED DESCRIPTION

[0012] It will be readily appreciated that the components of certain example embodiments, as generally described and illustrated in the figures herein, may be arranged and designed in a variety of different configurations. Therefore, the following detailed description of some example embodiments of systems, methods, apparatus, and computer program products for providing buffer status reporting triggered by radio link failure in scenarios involving multipath operation of user equipment is not intended to limit the scope of certain embodiments, but rather represents selected example embodiments.

[0013] The features, structures, or characteristics of the example embodiments described throughout this specification may be combined in one or more example embodiments in any suitable manner. For example, the use of the phrases "certain embodiments," "some embodiments," or other similar language throughout this specification refers to the fact that a particular feature, structure, or characteristic described in conjunction with the embodiment may be included in at least one embodiment. Therefore, the appearance of the phrases "certain embodiments," "in some embodiments," "in other embodiments," or other similar language throughout this specification does not necessarily all refer to the same group of embodiments, and the described features, structures, or characteristics may be combined in one or more example embodiments in any suitable manner.

[0014] Certain embodiments may have various aspects and features. These aspects and features may be applied individually or in any desired combination with each other. Other features, processes and elements may also be applied in combination with some or all of the aspects and features disclosed herein.

[0015] In addition, if necessary, the different functions or processes discussed below can be performed in different orders and / or simultaneously with each other. In addition, if necessary, one or more of the described functions or processes can be optional or can be combined. Therefore, the following description should be considered as an explanation of the principles and teachings of some example embodiments, rather than a limitation thereof.

[0016] Certain embodiments relate to buffer status reporting (BSR) to support multipath scenarios. The multipath scenarios described herein are scenarios where multiple paths are intentionally used, which is different from scenarios where there may be interference and phase shifts such as Rayleigh fading caused by, for example, reflection, refraction, etc. of the signal. For example, in certain embodiments, the UE may be configured with at least two paths, the at least two paths being used to send data to and receive data from the gNB. Specifically, the paths may include direct paths and indirect paths for sidelink (SL) multipath (MP) scenarios.

[0017] The third generation partnership project (3GPP) technical specification (TS) 38.321 defines various triggering events for the sidelink buffer status report for the standard. For example, the SL-BSR can be triggered based on SL data arrival, SL data presence, filling, and based on some SL-BSR control timers, such as retransmission timer and periodic timer.

[0018] Likewise, 3GPP TS 38.321 also defines various triggering events for uplink buffer status reporting. UL-BSR can be triggered based on UL data arrival, UL data priority, padding, and based on some UL-BSR control timers, such as a retransmission timer and a periodic timer.

[0019] In some embodiments, a UE may be connected to the same gNB using one direct path and one indirect path via a Layer 2 (L2) UE-to-network relay, or via another UE.

[0020] In sidelink MP relay, the gNB can manage the use of multipaths by considering reliability and throughput. Therefore, the gNB may need to have updated information about channel quality or buffer status for better decision-making on switching, releasing and / or adding of multipaths.

[0021] When there are multiple paths from the UE to the gNB, a radio link failure on one path does not necessarily mean that the UE recovers from the failure through RRC connection re-establishment.

[0022] After failure detection on one path, the gNB may need to determine whether to switch the relevant path or release the path. For example, the gNB may not need to determine whether to continue MP operation. The decision may take into account the radio quality and / or the amount of cached data. However, when data is ongoing, the buffer status report is triggered based on a timer. For example, the BSR may be triggered by a periodic timer or a retransmission timer. As a result, there may be a delay between the path failure and the next triggering of the BSR. In addition, the gNB may not know exactly how much data is directed via the indirect path, because the transmission of multipath separation RBs sent via the direct path and the indirect path over the PC5 interface may depend on the UE implementation and is not known to the gNB. These may lead to delayed decisions or decisions made without accurately knowing the buffer status from the gNB side, which may lead to unnecessary reconfiguration of multipath operations, including recovery of the indirect path after the failure of the indirect path.

[0023] One solution is that the gNB waits for the UE to send a BSR before deciding whether to keep the multipath relay operation, which prevents fast recovery from failures on one path and can lead to performance degradation in terms of throughput and reliability. Another solution is that the gNB decides whether to keep the multipath relay operation without caring about the amount of buffered data in the UE side or based on the amount of outdated buffered data. The disadvantage of this approach is that the gNB may need to reconfigure the multipath operation after receiving an updated BSR from the UE.

[0024] Certain embodiments involve triggering a BSR when a failure is detected on one of multiple paths between the UE and the gNB. For example, there may be at least one path other than the problematic path that is still available. For example, the path through the sidelink may fail, but the direct path may not be suspended or the failure may not be detected. If the UE is configured to operate with multiple paths using a sidelink relay, the failure may be detected over the Uu interface of the UE, the PC5 interface between the UE and the sidelink relay, or the Uu interface of the sidelink relay.

[0025] When the interface between the UE and the sidelink relay is not a 3GPP interface, any suitable mechanism may be used to detect a failure on the non-3GPP interface. By implementation, the 3GPP entity in the UE may know whether there is a failure on the non-3GPP interface. For example, when the maximum number of retransmissions for a specific destination has been reached, when an indication from the medium access control (MAC) has reached the maximum number of consecutive hybrid automatic repeat requests (HARQ) discontinuous transmissions (DTX) for a specific destination, when an integrity check failure has occurred from the sidelink packet data convergence protocol (PDCP) of the SL-SRB2 / 3 for a specific destination, and / or any other condition specified in 3GPP TS 38.331, a failure on the indirect path may be detected. For example, when a random access problem or the maximum number of retransmissions in the radio link control (RLC) has been reached, a failure on the direct path may be detected as specified in 3GPP TS 38.331. Other mechanisms or conditions for detecting or predicting radio link failures are also allowed.

[0026] Certain embodiments involve triggering a UL-BSR or SL-BSR, respectively, based on the path where the failure is detected. For example, if a failure is detected on an indirect path, the UE may trigger a SL-BSR. If a failure is detected on a direct path, the UE may trigger a UL-BSR. When MAC layer signaling is used to report the buffer size, whether the BSR MAC CE is for a SL-BSR or for a UL-BSR may be indicated by the corresponding logical channel identifier (LCID). To this end, the value of the LCID for the sidelink shared channel (SL-SCH) may be defined to indicate a UL-BSR.

[0027] In some embodiments, the BSR may be sent over a path that is not suspended and / or where no failure is detected. For example, the BSR may be sent over a normally operating path where no radio link failure is detected. If the UE is configured to operate with one direct path and one indirect path, and the failure is detected only on the direct path, the BSR may be reported to the gNB over the indirect path. If the failure is detected only on the indirect path, the BSR may be reported over the direct path. If there are more than two paths, the UE may send the BSR over any of the surviving paths, e.g., any of the paths that are not suspended and / or where no failure is detected. If a failure is detected on one path and no other path is available for transmission of the BSR, such that the transmission is suspended, the UE may not trigger a BSR even when a failure is detected.

[0028] In certain embodiments, a BSR is triggered when a radio link failure is predicted on one of multiple paths between the UE and the gNB. In this example, the BSR may be sent using the same path as the path of the predicted radio link failure (RLF) or on another path. The UE may predict an impending radio link failure using a UE-defined or network-configured metric. Such a metric may be based on one or more RLF parameters, such as N310 start, a predefined or configured number of out-of-sync indications to higher layers, or T310 expiration. The prediction may also depend on the UE's mobility and the UU or sidelink reference signal received power (SL-RSRP) slope, or RSRP degradation at a given time. The measurements may provide the UE with an indication that the UE's Uu link or PC5 link is rapidly deteriorating because the UE may be moving rapidly away from the gNB cell center or relay UE or towards the cell edge or other out-of-coverage scenarios.

[0029] Certain embodiments may include indicating a cache size for a subset of radio bearers (RBs) in a BSR. When a UE operates with sidelink multipath (SL MP) with one direct path and one indirect path, the UE may be configured with one of three types of RBs: direct RBs, indirect RBs, and multipath (MP) split RBs. If the UE detects a failure on any path, the UE may indicate a cache size for the MP split RBs.

[0030] When indicating the buffer size of MP split RBs, only data from logical channels associated with the relevant path may be considered. For example, if UL-BSR is triggered, the UE may only consider data from logical channels associated with the direct path. If SL-BSR is triggered, the UE may only consider data from logical channels associated with the indirect path.

[0031] Additionally, if the UE detects a failure on the direct path, the UE may also indicate the cache size of the direct RB. However, the UE may not indicate the cache size of the indirect RB. Similarly, if the UE detects a failure on the indirect path, the UE may also indicate the cache size of the indirect RB. However, the UE may not indicate the cache size of the direct RB.

[0032] If no data is available for transmission of an MP split RB, the UE may cancel the BSR or report the buffer size as zero. If no data is available for transmission of a direct RB or an indirect RB, the UE may not cancel the BSR but may report the buffer size as zero, as long as the BSR is not canceled by the MP split RB for which no data is available for transmission.

[0033] In certain embodiments, the triggering of a BSR is restricted such that the UE triggers a BSR if no BSR is triggered and / or sent for a certain duration before a failure is detected on a path. For example, a BSR is not automatically triggered when a failure is detected on a path within a certain duration after the last BSR is triggered / reported to the gNB. Alternatively, the UE may trigger a BSR if the UE is configured with at least one MP-split RB. Thus, for example, if the UE is not configured with MP-split RBs, the UE may not trigger a BSR. Alternatively, the UE may trigger a BSR if the buffer size at the time of RLF detection has changed by a certain amount compared to the last reported buffer size. For example, a BSR may be triggered if the buffer size is greater than a threshold last reported to the gNB. For example, the UE may trigger a BSR if the buffer size is X bytes larger than the last reported buffer size, or the UE may trigger a BSR if the buffer size level has changed compared to the last reported buffer size level.

[0034] In some embodiments, the sending of a triggered BSR may be performed before or together with the fault information to be sent to the gNB. If the BSR is to be sent before the fault information is sent, the MAC CE format may be used. If the BSR is to be sent together with the fault information, the BSR may be a MAC CE or RRC signaling.

[0035] In some embodiments, logical channel groups (LCGs) having logical channels associated with RBs of the MP split type may be prioritized. This prioritization may be applied when generating a BSR MAC CE.

[0036] Figure 1A An example rule set is shown that provides an example implementation of certain embodiments. Figure 1AAs shown, the rules may include the rules established in 3GPP TS 38.321v17.2.0, but may also specify that: a BSR is triggered when a sidelink radio link failure is detected on the direct path of the MAC entity, if the UE is configured to operate with multipath, as specified in 3GPP TS38.321, in which case the BSR may be referred to as a "regular BSR". Additionally, there may be further priority rules. For example, when a MAC PDU containing a BSR is to be established, if more than one LCG has data available for transmission of a logical channel associated with a multipath separation RB, the UE may report a long BSR for all LCGs that have data available for transmission. Otherwise, when a MAC PDU containing a BSR is to be established, if one LCG has data available for transmission of a logical channel associated with a multipath separation RB, a short BSR may be reported.

[0037] Figure 1B Another example rule set is shown that provides an example implementation of certain embodiments. Figure 1B As shown, the rules may include the rules established in 3GPP TS 38.321v17.2, but may also specify that: when a sidelink radio link failure is detected on an indirect path to the MAC entity, an SL-BSR is triggered if the UE is configured to operate in multipath as specified in 3GPP TS 38.331, in which case the SL-BSR may be referred to as a "regular SL-BSR".

[0038] Figure 1C Yet another example rule set is shown that provides an example implementation of certain embodiments. Figure 1C can be understood as Figure 1B Continuation of the same set of rules. The rules may include those established in 3GPP TS 38.321, but may also include a rule that if the SL-BSR is triggered by a sidelink radio link failure, the UE is to report a SL-BSR containing the cache status for all LCGs that have data available for transmission and have logical channels associated with (multiple) multipath separation RBs.

[0039] Figure 2 Methods according to some embodiments are shown. Figure 2 As shown, the method may include, at 210, communicating with a network via a plurality of paths, respective paths of the plurality of paths including: a first radio link of a user equipment and a second radio link of the user equipment.

[0040] The method may also include, at 220, detecting or predicting a radio link failure of the first radio link.

[0041] The method may also include, at 230, triggering a buffer status report to the network based on the detection or prediction of a radio link failure.

[0042] Triggering the buffer status may include triggering an uplink buffer status report when the first radio link failure is a failure of a direct path to the network. Triggering the buffer status report may include triggering a sidelink buffer status report when the first radio link failure is a failure of an indirect path to the network.

[0043] The method may further include, at 240, sending a buffer status report. When the first radio link failure is a detected failure of a direct path to the network, sending the buffer status report may be performed via an indirect path to the network. As another option, when the first radio link failure is a detected failure of an indirect path to the network, sending the buffer status report may be performed via a direct path to the network. When the radio link failure is a predicted failure, sending the buffer status report may be performed via the first radio link.

[0044] The buffer status report may include an indication of the buffer size for a subset of radio bearers used by the user equipment.

[0045] The trigger may additionally be based on the absence of at least one of a trigger or a transmission of another buffer status report within a predetermined time frame prior to the detection or prediction of the radio link failure.

[0046] The method may also include, at 236, reporting a buffer status report along with or before reporting the detected radio link failure.

[0047] The method may also include, at 234, generating a buffer status report based on the trigger, the buffer status report message having prioritized logical channel groups. The logical channel groups may be prioritized based on logical channels having associated radio bearers of a multipath separation type.

[0048] The first radio link and the second radio link may each include at least one of: a first Uu interface between the user equipment and the network, a PC5 interface between the user equipment and the relay user equipment, or a second Uu interface between the relay user equipment and the network.

[0049] Figure 2 The above process in may be performed by the user equipment. Additional processes may be performed by the network. The method may include, at 211, communicating with the user equipment via multiple paths, each of the multiple paths including: a first radio link of the user equipment and a second radio link of the user equipment. These may be the same paths mentioned in the description with reference to process 210.

[0050] At 241 , the network may receive a buffer status report from the user equipment based on the detection or prediction of a radio link failure of the first radio link.

[0051] At 251, the method may include determining processing of the plurality of paths based on the buffer status report.Therefore, at 261, the method may include controlling subsequent communications with the user equipment based on the determination.

[0052] The determining process may include determining to reestablish the first radio link based on an indication of a buffer size of the subset of radio bearers. In this case, the control communication at 261 may include reestablishing the first radio link.

[0053] When the cache status report has prioritized logical channel groups, where the logical channel groups are prioritized based on logical channels associated with radio bearers with a multipath separation type, determining processing may include determining to reestablish the first radio link based on the presence of data of the logical channel groups having logical channels associated with radio bearers with a multipath separation type.

[0054] Figure 3 An example of a system including an apparatus 10 according to an embodiment is shown. In an embodiment, the apparatus 10 may be a node, a host or a server in a communication network, or serve such a network, for example, the apparatus 10 may be a network node, a satellite, a base station, a node B, an evolved node B (eNB), a 5G node B or an access point, a next generation node B (NG-NB or gNB), a TRP, a HAPS, an integrated access and backhaul (IAB) node, and / or a WLAN access point, which is associated with a radio access network, such as an LTE network, 5G or NR. In some example embodiments, the apparatus 10 may be, for example, a gNB or other similar radio node.

[0055] It should be understood that in some example embodiments, the device 10 may include an edge cloud server as a distributed computing system, where the server and the radio nodes may be independent devices that communicate with each other via a radio path or via a wired connection, or they may be located in the same entity that communicates via a wired connection. For example, in certain example embodiments where the device 10 represents a gNB, it may be configured in a central unit (CU) and distributed unit (DU) architecture that divides the gNB functionality. In such an architecture, the CU may be a logical node that includes gNB functionality such as user data transmission, mobility control, radio access network sharing, positioning and / or session management. The CU may control the operation of the DU(s) via a mid-range interface referred to as the F1 interface, and the DU(s) may have one or more radio units (RUs) connected to the DU(s) via a front-range interface. The DU may be a logical node that includes a subset of the gNB functionality, depending on the functional division option. It should be noted that a person of ordinary skill in the art will understand that the device 10 may include Figure 3 Components or features not shown.

[0056] like Figure 3 As shown in the example of , the device 10 may include a processor 12 for processing information and executing instructions or operations. The processor 12 may be any type of general-purpose or special-purpose processor. In fact, the processor 12 may include, for example, a general-purpose computer, a special-purpose computer, a microprocessor, a digital signal processor (DSP), a field programmable gate array (FPGA), an application-specific integrated circuit (ASIC), and a processor based on a multi-core processor architecture, or one or more of any other processing components. Although in Figure 3 A single processor 12 is shown in the figure, but according to other embodiments, multiple processors may be utilized. For example, it should be understood that in some embodiments, the device 10 may include two or more processors, which may form a multi-processor system that can support multi-processing (e.g., in this case, the processor 12 may represent a multi-processor). In some embodiments, the multi-processor system may be tightly coupled or loosely coupled (e.g., to form a computer cluster).

[0057] Processor 12 may perform functions associated with the operation of apparatus 10, which may include, for example, precoding of antenna gain / phase parameters, encoding and decoding of individual bits forming communication messages, formatting of information, and overall control of apparatus 10, including processes associated with buffer status reporting triggered by radio link failures in scenarios involving multipath operation of user equipment.

[0058] The device 10 may also include or be coupled to a memory 14 (internal or external), which may be coupled to the processor 12 for storing information and instructions that can be executed by the processor 12. The memory 14 may be one or more memories of any type suitable for the local application environment, and may be implemented using any suitable volatile or non-volatile data storage technology, such as semiconductor-based memory devices, magnetic memory devices and systems, optical memory devices and systems, fixed memory, and / or removable memory. For example, the memory 14 may include any combination of random access memory (RAM), read-only memory (ROM), static memory such as a magnetic disk or optical disk, a hard disk drive (HDD), or any other type of non-transient machine or computer readable medium, or other suitable storage components. The instructions stored in the memory 14 may include program instructions or computer program codes that, when executed by the processor 12, enable the device 10 to perform the tasks described herein.

[0059] In one embodiment, the device 10 may also include or be coupled to a (internal or external) drive or port configured to receive and read an external computer-readable storage medium, such as an optical disk, a USB drive, a flash drive, or any other storage medium. For example, the external computer-readable storage medium may store a computer program or software executed by the processor 12 and / or the device 10.

[0060] In some embodiments, the device 10 may also include or be coupled to one or more antennas 15 for sending and receiving signals and / or data to and from the device 10. The device 10 may also include or be coupled to a transceiver 18, which is configured to send and receive information. The transceiver 18 may include, for example, multiple radio interfaces that may be coupled to (multiple) antennas 15, or may include any other suitable transceiver components. The radio interface may correspond to one or more of the following: multiple radio access technologies, including Global System for Mobile Communications (GSM), Narrowband Internet of Things (NB-IoT), LTE, 5G, WLAN, Bluetooth (BT), Bluetooth Low Energy (BT-LE), Near Field Communication (NFC), Radio Frequency Identifier (RFID), Ultra Wideband (UWB), MulteFire, etc. The radio interface may include components such as filters, converters (e.g., digital-to-analog converters, etc.), mappers, Fast Fourier Transform (FFT) modules, etc., to generate symbols for transmission via one or more downlinks and receive symbols (e.g., via uplinks).

[0061] Thus, the transceiver 18 may be configured to modulate information onto a carrier waveform for transmission by the antenna(s) 15, and to demodulate information received via the antenna(s) 15 for further processing by other elements of the apparatus 10. In other embodiments, the transceiver 18 may be capable of directly sending and receiving signals or data. Additionally or alternatively, in some embodiments, the apparatus 10 may include input and / or output devices (I / O devices), or input / output components.

[0062] In one embodiment, memory 14 may store software modules that provide functionality when executed by processor 12. The modules may include, for example, an operating system that provides operating system functionality for device 10. Memory may also store one or more functional modules, such as applications or programs, to provide additional functionality for device 10. The components of device 10 may be implemented in hardware, or as any suitable combination of hardware and software.

[0063] According to some embodiments, processor 12 and memory 14 may be included in or may form part of a processing circuit system / component or a control circuit system / component. In addition, in some embodiments, transceiver 18 may be included in or may form part of a transceiver circuit system / component.

[0064] As used herein, the term "circuitry" may refer to a hardware circuitry implementation only (e.g., analog and / or digital circuitry), a combination of hardware circuitry and software, a combination of analog and / or digital hardware circuitry and software / firmware, any portion of a hardware processor(s) and software (including a digital signal processor) that work together to enable a device (e.g., device 10) to perform various functions, and / or hardware circuit(s) and / or processor(s), or portions thereof, that use software for operation, but the software may not be present when the operation does not require the software. As another example, as used herein, the term "circuitry" may also cover an implementation of a hardware circuit or processor (or multiple processors), or a portion of a hardware circuit or processor, and its accompanying software and / or firmware. For example, the term "circuitry" may also cover a baseband integrated circuit in a server, a cellular network node or device, or other computing or network device.

[0065] As introduced above, in some embodiments, the device 10 may be or may be part of a network element or RAN node, such as a base station, access point, Node B, eNB, gNB, TRP, HAPS, IAB node, relay node, WLAN access point, satellite, etc. In an example embodiment, the device 10 may be a gNB or other radio node, or may be a CU and / or DU of a gNB. According to some embodiments, the device 10 may be controlled by the memory 14 and the processor 12 to perform functions associated with any of the embodiments described herein. For example, in some embodiments, the device 10 may be configured to perform one or more of the processes depicted in any flowchart or signaling diagram described herein, such as in Figures 1A to 2 In some embodiments, as discussed herein, for example, apparatus 10 may be configured to perform processes associated with providing a buffer status report triggered by a radio link failure in a scenario involving multipath operation of a user equipment.

[0066] Figure 3 An example of an apparatus 20 according to an embodiment is also shown. In an embodiment, the apparatus 20 may be a node or element in or associated with a communication network, such as a UE, a communication node, a mobile device (ME), a mobile station, a mobile device, a fixed device, an IoT device, or other device. As described herein, a UE may alternatively be referred to as, for example, a mobile station, a mobile device, a mobile unit, a mobile device, a user device, a user station, a wireless terminal, a tablet, a smart phone, an IoT device, a sensor or an NB-IoT device, a watch or other wearable device, a head mounted display (HMD), a vehicle, a drone, a medical device and its application (e.g., remote surgery), an industrial device and its application (e.g., a robot and / or other wireless device operating in an industrial and / or automated processing chain environment), a consumer electronic device, a device operating on a commercial and / or industrial wireless network, etc. As an example, the apparatus 20 may be implemented in, for example, a wireless handheld device, a wireless plug-in accessory, etc.

[0067] In some example embodiments, the apparatus 20 may include one or more processors, one or more computer-readable storage media (e.g., memory, storage, etc.), one or more radio access components (e.g., modems, transceivers, etc.), and / or a user interface. In some embodiments, the apparatus 20 may be configured to operate using one or more radio access technologies, such as GSM, LTE, LTE-A, NR, 5G, WLAN, WiFi, NB-IoT, Bluetooth, NFC, MulteFire, and / or any other radio access technology. It should be noted that those skilled in the art will appreciate that the apparatus 20 may include Figure 3Components or features not shown.

[0068] like Figure 3 As shown in the example of , the device 20 may include or be coupled to a processor 22 for processing information and executing instructions or operations. The processor 22 may be any type of general or special purpose processor. In fact, the processor 22 may include, for example, a general purpose computer, a special purpose computer, a microprocessor, a digital signal processor (DSP), a field programmable gate array (FPGA), an application specific integrated circuit (ASIC), and one or more processors based on a multi-core processor architecture. Although in Figure 3 A single processor 22 is shown in FIG. 1 , but according to other embodiments, multiple processors may be utilized. For example, it should be understood that in some embodiments, the apparatus 20 may include two or more processors, which may form a multiprocessor system that may support multiprocessing (e.g., in this case, the processor 22 may represent a multiprocessor). In some embodiments, the multiprocessor system may be tightly coupled or loosely coupled (e.g., to form a computer cluster).

[0069] Processor 22 may perform functions associated with the operation of device 20, including, as some examples, precoding of antenna gain / phase parameters, encoding and decoding of individual bits forming communication messages, formatting of information, and overall control of device 20, including processes associated with communication resource management.

[0070] The device 20 may also include or be coupled to a memory 24 (internal or external), which may be coupled to the processor 22 for storing information and instructions that can be executed by the processor 22. The memory 24 may be one or more memories, and may be any type of memory suitable for the local application environment, and may be implemented using any suitable volatile or non-volatile data storage technology, such as semiconductor-based memory devices, magnetic memory devices and systems, optical memory devices and systems, fixed memory, and / or removable memory. For example, the memory 24 may include any combination of random access memory (RAM), read-only memory (ROM), static memory such as a magnetic disk or optical disk, a hard disk drive (HDD), or any other type of non-transient machine or computer readable medium. The instructions stored in the memory 24 may include program instructions or computer program codes, which, when executed by the processor 22, enable the device 20 to perform tasks as described herein.

[0071] In an embodiment, the device 20 may also include or be coupled to a (internal or external) drive or port that is configured to accept and read an external computer-readable storage medium, such as an optical disk, a USB drive, a flash drive, or any other storage medium. For example, the external computer-readable storage medium may store a computer program or software for execution by the processor 22 and / or the device 20.

[0072] In some embodiments, the device 20 may also include or be coupled to one or more antennas 25 for receiving downlink signals and for transmitting from the device 20 via an uplink. The device 20 may also include a transceiver 28 configured to send and receive information. The transceiver 28 may also include a radio interface (e.g., a modem) coupled to the antenna 25. The radio interface may correspond to a plurality of radio access technologies, including one or more of GSM, LTE, LTE-A, 5G, NR, WLAN, NB-IoT, Bluetooth, BT-LE, NFC, RFID, UWB, etc. The radio interface may include other components, such as filters, converters (e.g., digital-to-analog converters, etc.), symbol demappers, signal shaping components, inverse fast Fourier transform (IFFT) modules, etc., to process symbols carried by a downlink or uplink, such as OFDM symbols.

[0073] For example, the transceiver 28 may be configured to modulate information onto a carrier waveform for transmission by the antenna(s) 25, and demodulate information received via the antenna(s) 25 for further processing by other elements of the device 20. In other embodiments, the transceiver 28 may be capable of directly sending and receiving signals or data. Additionally or alternatively, in some embodiments, the device 20 may include input and / or output devices (I / O devices). In some embodiments, the device 20 may also include a user interface, such as a graphical user interface or a touch screen.

[0074] In one embodiment, the memory 24 stores software modules that provide functionality when executed by the processor 22. The modules may include, for example, an operating system that provides operating system functionality for the device 20. The memory may also store one or more functional modules, such as applications or programs, to provide additional functionality for the device 20. The components of the device 20 may be implemented in hardware, or any suitable combination of hardware and software. According to an example embodiment, the device 20 may optionally be configured to communicate with the device 10 via a wireless or wired communication link 70 according to any radio access technology (such as NR).

[0075] According to some embodiments, processor 22 and memory 24 may be included in or may form part of a processing circuit system or a control circuit system. In addition, in some embodiments, transceiver 28 may be included in or may form part of a transceiver circuit system.

[0076] As described above, according to some embodiments, the apparatus 20 may be, for example, a UE, a SL UE, a relay UE, a mobile device, a mobile station, a ME, an IoT device and / or a NB-IoT device, etc. According to some embodiments, the apparatus 20 may be controlled by the memory 24 and the processor 22 to perform functions associated with any one of the embodiments described herein, such as in Figure 1A to Figure 2 One or more of the operations illustrated in or described with respect to the accompanying drawings, or any other method described herein. For example, in one embodiment, the apparatus 20 may be controlled to perform a process associated with providing a buffer status report triggered by a radio link failure in a scenario involving multipath operation of a user equipment, as described in detail elsewhere herein.

[0077] In some embodiments, an apparatus (e.g., apparatus 10 and / or apparatus 20) may include components for performing the methods, processes, or any variations discussed herein. Examples of these components may include one or more processors, memories, controllers, transmitters, receivers, and / or computer program codes for enabling the execution of any operations discussed herein.

[0078] In view of the foregoing, certain example embodiments provide several technical improvements, enhancements and / or advantages over prior art procedures and constitute at least an improvement in the technical field of radio network control and / or management. Certain embodiments may provide various benefits and / or advantages. For example, by immediately providing updated buffer size information to the gNB, sidelink resources and / or uplink resources may be reallocated to other UEs that need more resources, which may result in an increase in network capacity.

[0079] In some example embodiments, the functionality of any of the methods, processes, signaling diagrams, algorithms, or flowcharts described herein may be implemented by software and / or computer program code or a portion of code stored in a memory or other computer-readable or tangible medium and executed by a processor.

[0080] In some example embodiments, a device may include or be associated with at least one software application, module, unit, or entity, at least one software application, module, unit, or entity being configured as (multiple) arithmetic operations, or being configured as a program or program portion (including added or updated software routines) that can be executed by at least one operating processor or controller. Programs, also referred to as program products or computer programs, include software routines, applets, and macros, and may be stored in any device-readable data storage medium and may include program instructions for performing specific tasks. A computer program product may include one or more computer executable components, and when the program is run, one or more computer executable components are configured to perform some example embodiments. One or more computer executable components may be at least one software code or part of a code. Modifications and configurations required for the implementation of the functions of the example embodiments may be performed as routines, which may be implemented as added or updated (multiple) software routines. In one example, (multiple) software routines may be downloaded into the device.

[0081] As an example, software or computer program code or a portion of code can be in source code form, object code form or some intermediate form, and can be stored in a certain carrier, distributed medium or computer readable medium, which can be any entity or device capable of carrying the program. For example, such a carrier can include a recording medium, a computer memory, a read-only memory, an optoelectronic and / or electrical carrier signal, a telecommunications signal and / or a software distribution package. Depending on the required processing power, the computer program can be executed in a single electronic digital computer, or it can be distributed in multiple computers. Computer-readable medium or computer-readable storage medium can be a non-transient medium. As used herein, the term "non-transient" is a restriction on the medium itself (i.e., tangible, rather than a signal), rather than a restriction on data storage persistence (e.g., RAM to ROM).

[0082] In other example embodiments, the functions of the example embodiments may be performed by hardware or circuitry included in a device, such as by using an application specific integrated circuit (ASIC), a programmable gate array (PGA), a field programmable gate array (FPGA), or any other combination of hardware and software. In yet another example embodiment, the functions of the example embodiments may be implemented as signals, such as non-tangible components, which may be carried by electromagnetic signals downloaded from the Internet or other networks.

[0083] According to example embodiments, an apparatus, such as a node, a device or a corresponding component, may be configured as a circuit system, a computer or a microprocessor, such as a single-chip computer element, or as a chipset, which may include at least a memory for providing storage capacity for (multiple) arithmetic operations and / or an operation processor for performing (multiple) arithmetic operations.

[0084] The example embodiments described herein may apply to both singular and plural implementations, regardless of whether singular or plural language is used in conjunction with describing certain embodiments. For example, an embodiment describing the operation of a single network node may also apply to example embodiments including multiple instances of the network node, and vice versa.

[0085] Those skilled in the art will readily appreciate that the example embodiments described above may be practiced with processes in a different order and / or with hardware elements in a configuration different from that disclosed. Therefore, although some embodiments have been described based on these example embodiments, it will be apparent to those skilled in the art that certain modifications, variations, and alternative constructions will be apparent while remaining within the spirit and scope of the example embodiments.

[0086] Partial glossary:

[0087] BS Cache Status

[0088] BSR Cache Status Report

[0089] MP Multipath

[0090] SL-BSR Sidelink Buffer Status Report

[0091] UL-BSR Uplink Buffer Status Report

[0092] RB Radio Bearer

Claims

1. A device, include: at least one processor; as well as at least one memory storing instructions, which, when executed by the at least one processor, cause the apparatus to at least perform: communicating with a network via a plurality of paths, respective paths of the plurality of paths comprising: a first radio link of the device and a second radio link of the device; detecting or predicting a radio link failure of said first radio link; and Based on the detection or prediction of the radio link failure, a buffer status report is triggered to the network.

2. The apparatus according to claim 1, wherein triggering the cache status report comprises at least one of the following: triggering an uplink buffer status report when the first radio link failure is a failure of a direct path to the network; When the first radio link failure is a failure of an indirect path to the network, a sidelink buffer status report is triggered.

3. The apparatus of claim 1, wherein the instructions, when executed by the at least one, further cause the apparatus to perform at least one of the following: sending the buffer status report via an indirect path to the network when the first radio link failure is a detected failure of a direct path to the network; sending the buffer status report via a direct path to the network when the first radio link failure is a detected failure of an indirect path to the network; or When the radio link failure is a predicted failure, the buffer status report is sent over the first radio link.

4. An apparatus according to any of claims 1 to 3, wherein the buffer status report comprises an indication of a buffer size for a subset of radio bearers used by the apparatus. The apparatus of claim 4 , wherein the subset comprises a set of multipath separation radio bearers.

6. The apparatus according to any one of claims 1 to 5, wherein the triggering is additionally based on the absence of at least one of the triggering or transmission of another buffer status report within a predetermined time frame before the detection or prediction of the radio link failure.

7. The apparatus according to any one of claims 1 to 6, wherein the instructions, when executed by the at least one, further cause the apparatus to at least perform: The buffer status report is reported together with or before reporting the detected radio link failure.

8. The apparatus according to any one of claims 1 to 7, wherein the instructions, when executed by the at least one, further cause the apparatus to at least perform: The buffer status report is generated based on the trigger, the buffer status report having prioritized logical channel groups, wherein the logical channel groups are prioritized based on logical channels associated with radio bearers having a multipath separation type.

9. The apparatus according to any one of claims 1 to 8, wherein the first radio link and the second radio link each include at least one of the following: a first Uu interface between the apparatus and the network, a PC5 interface between the apparatus and a relay user equipment, or a second Uu interface between the relay user equipment and the network.

10. A method, include: communicating with a network via a plurality of paths, respective paths of the plurality of paths comprising: a first radio link of a user equipment and a second radio link of the user equipment; detecting or predicting a radio link failure of said first radio link; and Based on the detection or prediction of the radio link failure, a buffer status report is triggered to the network.

11. The method according to claim 10, wherein triggering the cache status report comprises at least one of the following: triggering an uplink buffer status report when the first radio link failure is a failure of a direct path to the network; When the first radio link failure is a failure of an indirect path to the network, a sidelink buffer status report is triggered.

12. The method according to claim 10, further comprising at least one of the following: sending the buffer status report via an indirect path to the network when the first radio link failure is a detected failure of a direct path to the network; sending the buffer status report via a direct path to the network when the first radio link failure is a detected failure of an indirect path to the network; or When the radio link failure is a predicted failure, the buffer status report is sent over the first radio link.

13. The method according to any of claims 10 to 12, wherein the buffer status report comprises an indication of a buffer size for a subset of radio bearers used by the user equipment. The method of claim 13 , wherein the subset comprises a set of multipath separation radio bearers.

15. The method according to any one of claims 10 to 14, wherein the triggering is additionally based on the absence of at least one of the triggering or the transmission of another buffer status report within a predetermined time frame before the detection or prediction of the radio link failure.

16. The method according to any one of claims 10 to 15, further comprising: include: The buffer status report is reported together with or before reporting the detected radio link failure.

17. The method according to any one of claims 10 to 16, further comprising: include: The buffer status report message is generated based on the trigger, the buffer status report message having prioritized logical channel groups, wherein the logical channel groups are prioritized based on logical channels associated with radio bearers having a multipath separation type.

18. The method according to any one of claims 10 to 17, wherein the first radio link and the second radio link each include at least one of the following: a first Uu interface between the user equipment and the network, a PC5 interface between the user equipment and a relay user equipment, or a second Uu interface between the relay user equipment and the network.

19. A device, include: Components for carrying out the method according to any one of claims 10 to 18.

20. A computer program product encoded with instructions for performing the method according to any one of claims 10 to 18.

21. A non-transitory computer readable medium encoded with instructions which, when executed in hardware, perform the method of any one of claims 10 to 18.

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