Methods and apparatus for managing a delay status reporting for an extended reality

Abstract

The disclosure relates to a 5G or 6G communication system for supporting a higher data transmission rate. Embodiments disclosed herein relate to methods (600) and systems (500) for a buffered data delay reporting for extended reality, and managing Medium Access Control (MAC) operations in a Fifth Generation (5G) New Radio (NR). The methods (600) include Delay Status Reporting (DSR) for extended reality, and scheduling by a network (504) for a buffered data for a UE (502), based on corresponding delay information reported. The methods (600) include DSR handling during a MAC Reset, DSR handling during a Service Data Unit (SDU) / PDU Set discard, and a Side-Link Paging Reference signal (SL-PRS) resource request handling during a MAC Reset. The methods (600) include cancelling a triggered DSR procedure upon resetting the MAC. Further, the methods (600) include cancelling a triggered SL-PRS resource request upon MAC Reset.

Description

METHODS AND APPARATUS FOR MANAGING A DELAY STATUS REPORTING FOR AN EXTENDED REALITY

[0001] Embodiments disclosed herein relate to wireless communication networks, and more particularly to a buffered data delay reporting for extended reality, and managing Medium Access Control (MAC) operations in a Fifth Generation (5G) New Radio (NR) node.

[0002] 5G mobile communication technologies define broad frequency bands such that high transmission rates and new services are possible, and can be implemented not only in "Sub 6GHz" bands such as 3.5GHz, but also in "Above 6GHz" bands referred to as mmWave including 28GHz and 39GHz. In addition, it has been considered to implement 6G mobile communication technologies (referred to as Beyond 5G systems) in terahertz bands (for example, 95GHz to 3THz bands) in order to accomplish transmission rates fifty times faster than 5G mobile communication technologies and ultra-low latencies one-tenth of 5G mobile communication technologies.

[0003] At the beginning of the development of 5G mobile communication technologies, in order to support services and to satisfy performance requirements in connection with enhanced Mobile BroadBand (eMBB), Ultra Reliable Low Latency Communications (URLLC), and massive Machine-Type Communications (mMTC), there has been ongoing standardization regarding beamforming and massive MIMO for mitigating radio-wave path loss and increasing radio-wave transmission distances in mmWave, supporting numerologies (for example, operating multiple subcarrier spacings) for efficiently utilizing mmWave resources and dynamic operation of slot formats, initial access technologies for supporting multi-beam transmission and broadbands, definition and operation of BWP (BandWidth Part), new channel coding methods such as a LDPC (Low Density Parity Check) code for large amount of data transmission and a polar code for highly reliable transmission of control information, L2 pre-processing, and network slicing for providing a dedicated network specialized to a specific service.

[0004] Currently, there are ongoing discussions regarding improvement and performance enhancement of initial 5G mobile communication technologies in view of services to be supported by 5G mobile communication technologies, and there has been physical layer standardization regarding technologies such as V2X (Vehicle-to-everything) for aiding driving determination by autonomous vehicles based on information regarding positions and states of vehicles transmitted by the vehicles and for enhancing user convenience, NR-U (New Radio Unlicensed) aimed at system operations conforming to various regulation-related requirements in unlicensed bands, NR UE Power Saving, Non-Terrestrial Network (NTN) which is UE-satellite direct communication for providing coverage in an area in which communication with terrestrial networks is unavailable, and positioning.

[0005] Moreover, there has been ongoing standardization in air interface architecture / protocol regarding technologies such as Industrial Internet of Things (IIoT) for supporting new services through interworking and convergence with other industries, IAB (Integrated Access and Backhaul) for providing a node for network service area expansion by supporting a wireless backhaul link and an access link in an integrated manner, mobility enhancement including conditional handover and DAPS (Dual Active Protocol Stack) handover, and two-step random access for simplifying random access procedures (2-step RACH for NR). There also has been ongoing standardization in system architecture / service regarding a 5G baseline architecture (for example, service based architecture or service based interface) for combining Network Functions Virtualization (NFV) and Software-Defined Networking (SDN) technologies, and Mobile Edge Computing (MEC) for receiving services based on UE positions.

[0006] As 5G mobile communication systems are commercialized, connected devices that have been exponentially increasing will be connected to communication networks, and it is accordingly expected that enhanced functions and performances of 5G mobile communication systems and integrated operations of connected devices will be necessary. To this end, new research is scheduled in connection with eXtended Reality (XR) for efficiently supporting AR (Augmented Reality), VR (Virtual Reality), MR (Mixed Reality) and the like, 5G performance improvement and complexity reduction by utilizing Artificial Intelligence (AI) and Machine Learning (ML), AI service support, metaverse service support, and drone communication.

[0007] Furthermore, such development of 5G mobile communication systems will serve as a basis for developing not only new waveforms for providing coverage in terahertz bands of 6G mobile communication technologies, multi-antenna transmission technologies such as Full Dimensional MIMO (FD-MIMO), array antennas and large-scale antennas, metamaterial-based lenses and antennas for improving coverage of terahertz band signals, high-dimensional space multiplexing technology using OAM (Orbital Angular Momentum), and RIS (Reconfigurable Intelligent Surface), but also full-duplex technology for increasing frequency efficiency of 6G mobile communication technologies and improving system networks, AI-based communication technology for implementing system optimization by utilizing satellites and AI (Artificial Intelligence) from the design stage and internalizing end-to-end AI support functions, and next-generation distributed computing technology for implementing services at levels of complexity exceeding the limit of UE operation capability

[0008] The principal object of embodiments herein is to disclose methods and systems for buffered data delay reporting for extended reality in wireless networks.

[0009] Another object of embodiments herein is to disclose methods and systems for configuring UE for buffered data delay reporting for the extended reality in the wireless networks.

[0010] Another object of the embodiments herein is to disclose methods and systems for scheduling by the network for a buffered data for the UE based on the corresponding delay information reported.

[0011] Another object of the embodiments herein is to disclose methods and systems for Delay Status Reporting (DSR) for extended reality.

[0012] Another object of the embodiments herein is to disclose methods and systems for managing Medium Access Control (MAC) operations in a New Radio (NR).

[0013] Another object of the embodiments herein is to disclose methods and systems for DSR handling during a MAC Reset, DSR handling during a Service Data Unit (SDU) / PDU Set discard, and Side-Link Paging Reference signal (SL-PRS) resource request handling during a MAC Reset.

[0014] Another object of the embodiments herein is to disclose methods and systems for cancelling a triggered DSR procedure upon resetting the MAC.

[0015] Another object of the embodiments herein is to disclose methods and systems for cancelling a triggered SL-PRS resource request upon MAC Reset, i.e., the UE MAC may cancel the triggered SL-PRS resource request upon the MAC reset.

[0016] Aspects of the disclosure are to address at least the above-mentioned problems and / or disadvantages and to provide at least the advantages described below. Accordingly, an aspect of the disclosure is to provide a method and apparatus for managing delay status reporting for extended reality.

[0017] Additional aspects will be set forth in part in the description which follows and, in part, will be apparent from the description, or may be learned by practice of the presented embodiments.

[0018] Accordingly, the embodiments herein provide a method for reporting a delay status by a User Equipment (UE). The method comprises configuring at least one remaining time threshold of at least one of a packet, a Packet Data Unit (PDU), a PDU Set, and a Service Data Unit (SDU). The remaining time threshold is received from a network. The method comprises determining a remaining time of at least one of the packet, the PDU, the PDU Set, and the SDU. The method comprises triggering, by a Medium Access Control (MAC) entity of the UE, a Delay Status Report (DSR) MAC Control Element (CE) for a delay status reporting, on determining the remaining time of at least one of the packet, the PDU, the PDU Set, and the SDU is less than the configured remaining time threshold.

[0019] Accordingly, the embodiments herein provide a UE comprising a processor, and a memory module. The processor is coupled with the memory module. The processor is configured to configure at least one remaining time threshold of at least one of a PDU, a PDU Set, and a SDU. The remaining time threshold is received from a network. The processor is configured to determine a remaining time of at least one of the packet, the PDU, the PDU Set, and the SDU. Further, the processor is configured to trigger a DSR MAC CE for a delay status reporting by a MAC entity, on determining the remaining time of at least one of the packet, the PDU, the PDU Set, and the SDU is less than the configured remaining time threshold.

[0020] These and other aspects of the example embodiments herein will be better appreciated and understood when considered in conjunction with the following description and the accompanying drawings. It should be understood, however, that the following descriptions, while indicating example embodiments and numerous specific details thereof, are given by way of illustration and not of limitation. Many changes and modifications may be made within the scope of the example embodiments herein without departing from the spirit thereof, and the example embodiments herein include all such modifications.

[0021] Advantages, and salient features of the invention will become apparent to those skilled in the art from the following detailed description, which, taken in conjunction with the annexed drawings, discloses exemplary embodiments of the invention.

[0022] For more enhanced communication system, there is a need for method and apparatus for managing delay status reporting for extended reality.

[0023] Embodiments herein are illustrated in the accompanying drawings, throughout which like reference letters indicate corresponding parts in the various figures. The embodiments herein will be better understood from the following description with reference to the following illustratory drawings. Embodiments herein are illustrated by way of examples in the accompanying drawings, and in which:

[0024] FIG. 1 illustrates an existing architecture of NG-RAN, according to existing arts;

[0025] FIG. 2a illustrates an existing New Radio protocol stack architecture for user plane based on 3rd Generation Partnership Project (3GPP) specifications, according to existing arts;

[0026] FIG. 2b illustrates an existing New Radio protocol stack architecture for control plane based on the 3GPP specifications, according to existing arts;

[0027] FIG. 3 illustrates a possible structure for Medium Access Control (MAC) entities when Main Cell Group (MCG) and Secondary Cell Group (SCG) are configured, according to existing arts;

[0028] FIG. 4 illustrates a MAC structure overview with two MAC entities, according to existing arts;

[0029] FIG. 5 depicts a system for reporting a delay status in wireless communications, according to embodiments as disclosed herein;

[0030] FIG. 6 depicts a method for reporting a delay status by a User Equipment (UE), according to embodiments as disclosed herein;

[0031] FIG. 7 depicts an Extended Reality (XR) Buffer Status Report (BSR) MAC Control Element (CE) format to carry BSR contents for XR services, according to embodiments as disclosed herein;

[0032] FIG. 8 depicts an enhanced BSR MAC CE format to carry BSR contents for XR and non-XR services, according to embodiments as disclosed herein;

[0033] FIG. 9 depicts an XR BSR MAC CE wherein for a XR LCG there may be zero, one or more BSR contents (i.e., Delay Amount field and / or Buffer Size field), according to embodiments as disclosed herein;

[0034] FIG. 10 depicts a procedure for delay status reporting, according to embodiments as disclosed herein;

[0035] FIG. 11 depicts a sample structure of Short Delay reporting BSR MAC CE carrying 5-bit delay information of PDU set / PDU, according to embodiments as disclosed herein;

[0036] FIG. 12 depicts a sample structure of Short Delay reporting BSR MAC CE carrying 3-bit delay information of PDU set / PDU, according to embodiments as disclosed herein;

[0037] FIG. 13 depicts a sample structure of Long Delay reporting BSR MAC CE carrying 8-bit delay information of PDU set / PDU, according to embodiments as disclosed herein;

[0038] FIG. 14 depicts a sample structure of enhanced common BSR MAC CE carrying delay information or buffer status, according to embodiments as disclosed herein;

[0039] FIG. 15 depicts a sample structure of DSR MAC CE, according to embodiments as disclosed herein;

[0040] FIG. 16 illustrates a method for DSR handling during MAC reset, according to embodiments as disclosed herein;

[0041] FIG. 17 illustrates a method for DSR handling during SDU / PDU set discard, according to embodiments as disclosed herein; and

[0042] FIG. 18 illustrates a method for a SL-PRS resource request handling during MAC reset, according to embodiments as disclosed herein.

[0043] The embodiments herein and the various features and advantageous details thereof are explained more fully with reference to the non-limiting embodiments that are illustrated in the accompanying drawings and detailed in the following description. Descriptions of well-known components and processing techniques are omitted so as to not unnecessarily obscure the embodiments herein. The examples used herein are intended merely to facilitate an understanding of ways in which the embodiments herein may be practiced and to further enable those of skill in the art to practice the embodiments herein. Accordingly, the examples should not be construed as limiting the scope of the embodiments herein.

[0044] For the purposes of interpreting this specification, the definitions (as defined herein) will apply and whenever appropriate the terms used in singular will also include the plural and vice versa. It is to be understood that the terminology used herein is for the purposes of describing particular embodiments only and is not intended to be limiting. The terms "comprising", "having" and "including" are to be construed as open-ended terms unless otherwise noted.

[0045] The words / phrases "exemplary", "example", "illustration", "in an instance", "and the like", "and so on", "etc.", "etcetera", "e.g.," , "i.e.," are merely used herein to mean "serving as an example, instance, or illustration." Any embodiment or implementation of the present subject matter described herein using the words / phrases "exemplary", "example", "illustration", "in an instance", "and the like", "and so on", "etc.", "etcetera", "e.g.," , "i.e.," is not necessarily to be construed as preferred or advantageous over other embodiments.

[0046] Embodiments herein may be described and illustrated in terms of blocks which carry out a described function or functions.　These blocks, which may be referred to herein as managers, units, modules, hardware components or the like, are physically implemented by analog and / or digital circuits such as logic gates, integrated circuits, microprocessors, microcontrollers, memory circuits, passive electronic components, active electronic components, optical components, hardwired circuits and the like, and may optionally be driven by a firmware. The circuits may, for example, be embodied in one or more semiconductor chips, or on substrate supports such as printed circuit boards and the like.　The circuits constituting a block may be implemented by dedicated hardware, or by a processor (e.g., one or more programmed microprocessors and associated circuitry), or by a combination of dedicated hardware to perform some functions of the block and a processor to perform other functions of the block.　Each block of the embodiments may be physically separated into two or more interacting and discrete blocks without departing from the scope of the disclosure.　Likewise, the blocks of the embodiments may be physically combined into more complex blocks without departing from the scope of the disclosure.

[0047] It should be noted that elements in the drawings are illustrated for the purposes of this description and ease of understanding and may not have necessarily been drawn to scale. For example, the flowcharts / sequence diagrams illustrate the method in terms of the steps required for understanding of aspects of the embodiments as disclosed herein. Furthermore, in terms of the construction of the device, one or more components of the device may have been represented in the drawings by conventional symbols, and the drawings may show only those specific details that are pertinent to understanding the present embodiments so as not to obscure the drawings with details that will be readily apparent to those of ordinary skill in the art having the benefit of the description herein. Furthermore, in terms of the system, one or more components / modules which comprise the system may have been represented in the drawings by conventional symbols, and the drawings may show only those specific details that are pertinent to understanding the present embodiments so as not to obscure the drawings with details that will be readily apparent to those of ordinary skill in the art having the benefit of the description herein.

[0048] The accompanying drawings are used to help easily understand various technical features and it should be understood that the embodiments presented herein are not limited by the accompanying drawings. As such, the present disclosure should be construed to extend to any modifications, equivalents, and substitutes in addition to those which are particularly set out in the accompanying drawings and the corresponding description. Usage of words such as first, second, third etc., to describe components / elements / steps is for the purposes of this description and should not be construed as sequential ordering / placement / occurrence unless specified otherwise.

[0049] Extended Reality (XR) is an umbrella term for different realities including a Virtual Reality (VR), an Augmented Reality (AR), and a Mixed Reality (MR), and is considered as an essential technology to enable the realization of digital twin / meta universe. XR is incorporated as an agreed work item in Fifth Generation (5G) Advanced (i.e., 3GPP Release 18), which is targeted to provide a communication system framework that fulfills challenging needs of high data rate, low latency, and power efficient connectivity for XR applications.

[0050] A Protocol Data Convergence Protocol (PDCP), a Radio Link Control (RLC), and a Medium Access Control (MAC) are layer-2 sub-layers, and are involved in a number of functionalities for data plane processing of the transmitted and received packets. A Buffer Status Report (BSR) reporting procedure involves sending of the buffered data status (For example, size of the buffered data) across different Logical channel Groups (LCGs). This facilitates the scheduling operation of a network, i.e., the network can allocate the uplink grants to a User Equipment (UE) in order to serve the buffered data at the UE. However, there is no information on the delay status of the buffered data. In general, the buffered data may have different delay status as the data storage at the buffer may have happen at different points in time. Moreover, different services have different packet delay budget which implies the buffered data (i.e., a packet or a Service Data Unit (SDU)) is subject to discard when it overshoots the packet delay budget limit, or any associated limit configured. The SDU discard procedure involves discard of a PDCP SDU when the associated timer is expired or the successful delivery of a PDCP SDU is confirmed from a peer PDCP entity; for example, through a PDCP status report.

[0051] For XR applications, the existing buffer status reporting may not be efficient and effective as the XR application may be extremely delay sensitive, and require low latency of performance. As a result, existing mechanism may lead to an in-efficient scheduling and / or excessive packet discard, if applied to XR applications. Thus, it is desired to address the above mentioned disadvantages or other shortcomings.

[0052] A Next-Generation Radio Access Network (NG-RAN) node relates to either a gNodeB (gNB) which provides a New Radio (NR) user plane and control plane protocol terminations towards a UE, or an ng-eNB which provides Evolved Universal Terrestrial Radio Access Network (E-UTRA) user plane and control plane protocol terminations towards the UE. The gNBs and ng-eNBs are interconnected with each other by means of an Xn interface. The gNBs and ng-eNBs are also connected by means of Next Generation (NG) interfaces to 5G Core (5GC), and are more specifically connected to an Access and Mobility Management Function (AMF) by means of Next Generation Core (NG-C) interface and to a User Plane Function (UPF) by means of the Next Generation User-plane (NG-U) interface. FIG. 1 shows an existing architecture of NG-RAN. The NG-RAN consists of a set of gNBs connected to the 5GC through the NG interface. The gNBs can be interconnected through the Xn interface. The gNB may consist of a gNB Centralized Unit (CU) and one or more gNB Distributed Units (DU). The gNB-CU and the gNB-DU are connected via an F1 interface.

[0053] FIG. 2a shows an existing NR radio protocol stack architecture for user plane based on 3rd Generation Partnership Project (3GPP) specifications. Further, FIG. 2b shows an NR radio protocol stack architecture for control plane based on the 3GPP specifications. The protocol stack for the control plane causes Packet Data Convergence Protocol (PDCP), Radio Link Control (RLC) and Medium Access Control (MAC) sublayers (terminated in gNB on the network side) to perform functions listed in clause 6. Further, a Radio Resource Control (RRC) (terminated in gNB on the network side) performs the functions listed in clause 7. Furthermore, a Non Access Stratum (NAS) control protocol (terminated in AMF on the network side) performs the functions listed for instance: authentication, mobility management, security control, and so on.

[0054] Main services and functions of the MAC sublayer include the following: mapping between logical channels and transport channels, multiplexing / de-multiplexing of MAC SDUs belonging to one or different logical channels into / from Transport Blocks (TB) delivered to / from the physical layer on transport channels, scheduling information reporting, error correction through an Automatic Repeat reQuest (ARQ) - Hybrid ARQ (HARQ) (one HARQ entity per cell in case of Carrier Aggregation (CA), priority handling between UEs by means of dynamic scheduling, priority handling between logical channels of one UE by means of logical channel prioritization, and priority handling between overlapping resources of one UE and Padding.

[0055] A single MAC entity may support multiple numerologies, transmission timings and cells. Mapping restrictions in logical channel prioritization can control which numerology (ies), cell(s), and transmission timing(s) a logical channel can use.

[0056] The MAC entity of the UE handles transport channels. When the UE is configured with a Secondary Cell Group (SCG), two MAC entities are configured to the UE. One for a Main Cell Group (MCG) and one for the SCG. When the UE is configured with Dual Active Protocol Stacks (DAPS) handover, two MAC entities are used by the UE. One for the source cell (source MAC entity), and one for the target cell (target MAC entity). The functions of the different MAC entities in the UE operate independently unless otherwise specified. Timers and parameters used in each MAC entity are configured independently unless otherwise specified. The serving cells, Cell Radio Network Temporary Identifier (C-RNTI), radio bearers, logical channels, upper and lower layer entities, Logical Channel Group (LCGs), and HARQ entities considered by each MAC entity refer to those mapped to that MAC entity unless otherwise specified. If the MAC entity is configured with one or more Secondary Cells (SCells), there are multiple Downlink Shared Channel (DL-SCH) and there may be multiple Uplink Shared Channel (UL-SCH) as well as multiple Random Access Channel (RACH) per MAC entity. One DL-SCH, one UL-SCH, and one RACH on a Special Cell (SpCell), one DL-SCH, zero or one UL-SCH and zero or one RACH for each SCell. If the MAC entity is not configured with any SCell, there is one DL-SCH, one UL-SCH, and one RACH per MAC entity. FIG. 3 illustrates a possible structure for the MAC entities when MCG and SCG are configured. FIG. 4 illustrates a MAC structure overview with two MAC entities.

[0057] As mentioned before, the MAC entity handles prioritization between different logical channels. The MAC entity in UE allocates resources (grants) received from the gNB considering the priority of the logical channels. For example, if the grants received from the network are sufficient to transmit information from only one of the logical channels, then the UE allocates the resources to the information from the higher priority logical channel.

[0058] A UE MAC triggers the transmission of Uplink (UL) Control information (e.g. UL MAC Control Element (CE)) based on various conditions. Actual transmission of the UL MAC CE is dependent on different aspects such as the allocation of resources for transmission by the network. Thus, the trigger for transmission of UL MAC CE, and the actual transmission of the UL MAC CE may happen at two different points of time. A triggered UL MAC CE may be cancelled by MAC based on various events. During cancellation, the UE may clear the UL MAC CE, from a transmission buffer or retransmission buffer of the UE. If the UE needs to send a Scheduling Request (SR) for requesting resources for transmission of MAC CE, then the UE cancels (i.e., clears) the SR when it is not sent. If the SR is already sent and the resources are allocated to transmit the UL MAC CE, then the UE may skip using those resources. Similarly, if a random access is triggered for the SR transmission, such as a random access process may be stopped, and then the usage of any resource allocated to the UE through random access may be skipped.

[0059] Upper layers of protocol stack like UE RRC may initiate UE MAC reset, when requested by upper layers or during a handover (e.g., when receiving ReconfigurationWithSync message) or during an SCG deactivation. MAC reset may be triggered during Lower Layer triggered mobility as well. Upon the MAC reset, a set of variables may be reset while a set of variables may be maintained. Similarly, some of the procedures may be continued while some may be abandoned. This is unlike a MAC release where all the state variables are released, and all the procedures are cleared.

[0060] Further, side-link supports UE-to-UE direct communication using different side-link resource allocation modes, physical-layer signals / channels, and physical layer procedures. The physical layer signals that may be transmitted between UE includes Side-Link Paging Reference signal (SL-PRS). SL-PRS transmission can be triggered either by lower layer signaling from the peer UE or the UE's own higher layer. The SL-PRS resource request is used to provide gNB with information about the SL-PRS that the UE needs to transmit.

[0061] Hence, there is a need in the art for solutions which will overcome the above mentioned drawback(s), among others.

[0062] Accordingly, the embodiments herein provide a method for reporting a delay status by a User Equipment (UE). The method comprises configuring at least one remaining time threshold of at least one of a packet, a Packet Data Unit (PDU), a PDU Set, and a Service Data Unit (SDU). The remaining time threshold is received from a network. The method comprises determining a remaining time of at least one of the packet, the PDU, the PDU Set, and the SDU. The method comprises triggering, by a Medium Access Control (MAC) entity of the UE, a Delay Status Report (DSR) MAC Control Element (CE) for a delay status reporting, on determining the remaining time of at least one of the packet, the PDU, the PDU Set, and the SDU is less than the configured remaining time threshold.

[0063] Accordingly, the embodiments herein provide a UE comprising a processor, and a memory module. The processor is coupled with the memory module. The processor is configured to configure at least one remaining time threshold of at least one of a PDU, a PDU Set, and a SDU. The remaining time threshold is received from a network. The processor is configured to determine a remaining time of at least one of the packet, the PDU, the PDU Set, and the SDU. Further, the processor is configured to trigger a DSR MAC CE for a delay status reporting by a MAC entity, on determining the remaining time of at least one of the packet, the PDU, the PDU Set, and the SDU is less than the configured remaining time threshold.

[0064] These and other aspects of the example embodiments herein will be better appreciated and understood when considered in conjunction with the following description and the accompanying drawings. It should be understood, however, that the following descriptions, while indicating example embodiments and numerous specific details thereof, are given by way of illustration and not of limitation. Many changes and modifications may be made within the scope of the example embodiments herein without departing from the spirit thereof, and the example embodiments herein include all such modifications.

[0065] The embodiments herein disclose methods and systems for buffered data delay reporting for Extended Reality (XR), and managing Medium Access Control (MAC) operations in a New Radio (NR). Referring now to the drawings, and more particularly to FIGs. 5 through 18, where similar reference characters denote corresponding features consistently throughout the figures, there are shown embodiments.

[0066] In the complete description herein, terms such as enhanced Buffer Status Report (BSR), XR BSR, and Delay Status Report (DSR) have been used interchangeably, and they imply the same interpretation and purpose.

[0067] In the complete description herein, terms such as enhanced BSR MAC Control Element (CE), new MAC CE, XR MAC CE, XR BSR MAC CE, and DSR MAC CE have been used interchangeably, and they imply the same interpretation and purpose.

[0068] In the complete description herein, terms such as delay information / delay amount, and remaining time have been used interchangeably, and they imply the same interpretation and purpose.

[0069] In the complete description herein, terms such as buffer info, and buffer size have been used interchangeably, and they imply the same interpretation and purpose.

[0070] Embodiments herein disclose methods and systems for buffered data delay reporting for extended reality in wireless networks. The method includes configuring UE for buffered data delay reporting for the extended reality in the wireless networks. The method includes determining, composing and sending the buffered data delay reporting for the extended reality in the wireless networks. The method includes scheduling by a network for the buffered data for the UE based on the corresponding delay information reported.

[0071] In an embodiment herein, one or more delay information (i.e., one or more instances or fields that carry delay information, for simplicity, this may be further referred to herein as also as "one or more delay information" herein) is included in a Medium Access Control (MAC) Control Element (CE); for example, an enhanced Buffer Status Report (BSR) MAC CE or a new MAC CE (e.g., a Delay Status Reporting (DSR) MAC CE). Each delay information may be associated to a corresponding buffer data size information. The MAC CE, therefore, may comprise of at least one of buffer data size information field, and delay information for a buffer data field.

[0072] In an embodiment herein, a delay information field for a buffered data corresponds to at least one Logical Channel Group (LCG) which may be a group of Logical Channels (LCs). Further, at least one LCG in the MAC CE or the MAC CE entirely may pertain to Extended Reality (XR) services. Further, there may be one or more delay information fields for each LCG included in the MAC CE. Further, each delay information field may correspond to at least one buffered data size field included for the LCG in the MAC CE, and each of these buffered data size field may also be included along with the delay information field (for example, together, one-after-other, or in same order to provide a clear mapping between delay information and buffered data size in the MAC CE to the receiving entity).

[0073] In an embodiment herein, when more than one delay information fields are included for the buffered data, they may be arranged in either ascending order or descending order of their delay values. This may be for multiple delay information fields for a single LCG or multiple delay information fields for multiple LCGs. Alternatively, multiple delay information fields for multiple LCGs may be arranged in the priority order of the LCGs.

[0074] In an embodiment herein, the delay information for the buffered data may be at least one of the delay already experienced by the data since it was buffered (for example, data buffered in the Radio Link Control (RLC) storage and / or in a Protocol Data Convergence Protocol (PDCP) storage, where RLC storage and / PDCP storage may also be commonly referred to as L2 buffer) or further delay which the buffered data may withstand or allowed as per configuration or performance requirement perspective (for example, remaining duration for a Packet Delay Budget (PDB) or a PDU Set Delay Budget (PSDB) or remaining time for the pertinent PDCP discard timer expiry).

[0075] In an embodiment herein, the delay information for the buffered data is quantized in at least one of uniform or non-uniform steps to derive mapping indices that represent the value or the range of values for the delay. For example, at least one static or semi-static table (for example, delay table for XR and / or enhanced BSR table for XR) with different values or ranges of values of delay can be specified by the standards or different values or ranges of values of delay can be determined by specified / configured formulation or different values or ranges of values of delay can be configured by signaling by the network. The index to the table entry can then represent the value or range of values for delay and can be utilized to be signaled in the delay information field. Alternatively, the delay information could be expressed as a percentage or a fraction of the relevant PDB or PSDB for the XR applications (or logical channels or logical channel groups).

[0076] FIG. 5 depicts a system 500 for reporting a delay status in wireless communications. The system 500 comprises a User Equipment (UE) 502, and a network 504, where the UE 502 performs buffered data delay reporting for extended reality. The UE 502 comprises a processor 506, a protocol stack 508, a communication module 510, and a memory module 512.

[0077] In an embodiment herein, the processor 506 further comprises a configuration module 514, and a Delay Status Report (DSR) module 516.

[0078] In an embodiment herein, the configuration module 514 can configure at least one remaining time threshold of at least one of a packet, a Packet Data Unit (PDU), a PDU Set, and a Service Data Unit (SDU). The remaining time threshold is received from the network 504. The remaining time threshold is indicated with a threshold index. The threshold index can be interpreted implicitly based on the order of one or more configured remaining time thresholds in a Radio Resource Control (RRC) signaling message. Alternatively, the threshold index can be configured explicitly in the RRC signaling message.

[0079] In an embodiment herein, the DSR module 516 can determine a remaining time of at least one of the packet, the PDU, the PDU Set, and the SDU. The DSR module 516 can trigger a MAC entity 518 of the protocol stack 508, on determining the remaining time of at least one of the packet, the PDU, the PDU Set, and the SDU is less than the configured remaining time threshold.

[0080] In an embodiment herein, the protocol stack 508 comprises the MAC entity 518, and a Packet Data Convergence Protocol (PDCP) layer 520. The MAC entity 518 is triggered by the DSR module 516. The MAC entity 518 triggers a DSR MAC Control Element (CE) for a delay status reporting, based on determining the remaining time of at least one of the packet, the PDU, the PDU Set, and the SDU is less than the configured remaining time threshold.

[0081] In an embodiment herein, the MAC entity 518 can determine the remaining time of the PDU Set from the remaining time of the PDCP discard timer of a first SDU of the PDU Set, if the first SDU of the PDU Set has the remaining time of the PDCP discard timer lesser than the configured at least one remaining time threshold.

[0082] In an embodiment herein, the MAC entity 518 considers the remaining time as an actual remaining time for the delay status reporting at a transmission instant. The MAC entity 518 transmits the DSR MAC CE including a buffer status with the actual remaining time at the transmission instant.

[0083] In an embodiment herein, the MAC entity 518 reports at least one of an LCG index or identity, a threshold index, a remaining time, and a size of buffered data for at least one of the packet, the PDU, the PDU Set, and the SDU pertaining to at least one of the LCG index, the threshold index, the remaining time reported, and so on.

[0084] In an embodiment herein, the MAC entity 518 considers the remaining time of the PDU Set, when the PDU Set based discard has been configured for a relevant radio bearer belonging to at least one of a logical channel, and an LCG. The MAC entity 518 considers all SDUs of the PDU Set, for reporting the size of buffered data as the delay status reporting, if at least one SDU of the PDU Set has the remaining time of a PDCP discard timer lesser than the configured remaining time threshold. The MAC entity 518 considers only the SDUs of the PDU Set for delay status reporting that have been received by the PDCP layer 520 of the UE 502, and for which the PDCP discard timer is running.

[0085] In an embodiment herein, the MAC entity 518 considers the remaining time of at least one of the PDU, and the SDU, when the PDU Set based discard has not been configured for the relevant radio bearer belonging to at least one of the logical channel, and the LCG. The MAC entity 518 considers at least one of the PDU, and the SDU, if at least one of the PDU, and the SDU has the remaining time of the PDCP discard timer lesser than the configured at least one remaining time threshold.

[0086] In an embodiment herein, the MAC entity 518 verifies an uplink data pertaining to at least one of the packet, the PDU, the PDU Set, and the SDU, after triggering the DSR MAC CE for the delay status reporting based on the remaining time threshold. The MAC entity 518 skips considering a discarded data for the delay status reporting in the DSR MAC CE, if the PDCP discard timer associated with the uplink data is completely expired by the time the DSR MAC CE is transmitted. The MAC entity 518 cancels transmission of the DSR MAC CE, if all the uplink data is discarded by the time the DSR MAC CE is transmitted. The MAC entity 518 considers a new uplink data to be included for the DSR MAC CE, if the new uplink data is available by the time the DSR MAC CE is transmitted.

[0087] In an embodiment herein, the MAC entity 518 receives an indication of at least one of a congestion activation status, and a congestion deactivation status from the network 504. The MAC entity 518 considers a remaining time of the uplink data for the delay status reporting as per the value of the PDCP discard timer configured for the uplink data during one of before congestion activation, and after congestion activation, on receiving the indication as activation of the congestion. The MAC entity 518 suspends reporting of the delay status, during the congestion, for one or more PDU Sets with a PDU Set Importance (PSI) value below a PSI level, on receiving the indication as activation of the congestion. The PSI level is determined based on a UE implementation. The MAC entity 518 resumes reporting of the delay status for the one or more PDU Sets with the PSI value below the PSI level, on receiving the indication as deactivation of the congestion.

[0088] In an embodiment herein, the MAC entity 518 performs a MAC reset, on receiving a MAC reset request from the upper layers of the UE (502). The MAC entity 518 cancels the triggered Delay Status Reporting (DSR), upon resetting the MAC. In an embodiment herein, the MAC entity 518 cancels triggering a Side-Link Positioning Reference Signal (SL-PRS) resource request, upon resetting the MAC.

[0089] In an embodiment herein, the MAC entity 518 cancels transmission of the DSR MAC CE, on receiving one or more grants to transmit including all SDUs, and PDU Sets associated with the DSR.

[0090] In an embodiment herein, the processor 506 can process and execute data of a plurality of modules of the UE 502. The processor 506 can be configured to execute instructions stored in the memory module 512. The processor 506 may comprise one or more of microprocessors, circuits, and other hardware configured for processing. The processor 506 can be at least one of a single processer, a plurality of processors, multiple homogeneous or heterogeneous cores, multiple Central Processing Units (CPUs) of different kinds, microcontrollers, special media, and other accelerators. The processor 506 may be an application processor (AP), a graphics-only processing unit (such as a graphics processing unit (GPU), a visual processing unit (VPU)), and / or an Artificial Intelligence (AI)-dedicated processor (such as a neural processing unit (NPU)).

[0091] In an embodiment herein, the plurality of modules of the processor 506 of the UE 502 can communicate via the communication module 510. The communication module 510 may be in the form of either a wired network or a wireless communication network module. The wireless communication network may comprise, but not limited to, Global Positioning System (GPS), Global System for Mobile Communications (GSM), Wi-Fi, Bluetooth low energy, Near-field communication (NFC), and so on. The wireless communication may further comprise one or more of Bluetooth, ZigBee, a short-range wireless communication (such as Ultra-Wideband (UWB)), and a medium-range wireless communication (such as Wi-Fi) or a long-range wireless communication (such as 3G / 4G / 5G / 6G and non-3GPP technologies or WiMAX), according to the usage environment.

[0092] In an embodiment herein, the memory module 512 may comprise one or more volatile and non-volatile memory components which are capable of storing data and instructions of the modules of the UE 502 to be executed. Examples of the memory module 512 can be, but not limited to, NAND, embedded Multi Media Card (eMMC), Secure Digital (SD) cards, Universal Serial Bus (USB), Serial Advanced Technology Attachment (SATA), solid-state drive (SSD), and so on. The memory module 512 may also include one or more computer-readable storage media. Examples of non-volatile storage elements may include magnetic hard discs, optical discs, floppy discs, flash memories, or forms of electrically programmable memories (EPROM) or electrically erasable and programmable (EEPROM) memories. In addition, the memory module 512 may, in some examples, be considered a non-transitory storage medium. The term "non-transitory" may indicate that the storage medium is not embodied in a carrier wave or a propagated signal. However, the term "non-transitory" should not be interpreted to mean that the memory module 512 is non-movable. In certain examples, a non-transitory storage medium may store data that can, over time, change (for example, in Random Access Memory (RAM) or cache).

[0093] FIG. 5 shows example modules of the UE 502, but it is to be understood that other embodiments are not limited thereon. In other embodiments, the UE 502 may include less or more number of modules. Further, the labels or names of the modules are used only for illustrative purpose and does not limit the scope of the invention. One or more modules can be combined together to perform same or substantially similar function in the base station 502.

[0094] FIG. 6 depicts a method 600 for reporting a delay status by the UE 502. The method 600 comprises configuring at least one remaining time threshold of at least one of a packet, a PDU, a PDU Set, and an SDU, as depicted in step 602. The remaining time threshold is received from the network 504. Thereafter, the method 600 comprises determining a remaining time of at least one of the packet, the PDU, the PDU Set, and the SDU, as depicted in step 604. The method 600 comprises triggering, by the MAC entity 518 of the UE 502, a DSR MAC CE for a delay status reporting, on determining the remaining time of at least one of the packet, the PDU, the PDU Set, and the SDU is less than the configured remaining time threshold, as depicted in step 606.

[0095] The various actions in method 600 may be performed in the order presented, in a different order or simultaneously. Further, in some embodiments, some actions listed in FIG. 6 may be omitted.

[0096] In an embodiment herein, a new MAC CE (for example, enhanced BSR MAC CE or DSR MAC CE) can be used to carry only buffered data status for XR services (or LCs or LCGs). The new MAC CE for XR services is identified and distinguished from legacy BSR MAC CE for non-XR services by one or more new Logical Channel Identities (LCIDs). In an embodiment herein, the new MAC CE for XR services is identified and distinguished from legacy BSR MAC CE for non-XR services by one or more new extended Logical Channel Identities (eLCIDs). In an embodiment herein, an eLCID for identifying new MAC CE for XR service is one octet in size. In an embodiment herein, the eLCID for identifying new MAC CE for XR service is two octets in size. Further, the new MAC CE can be a short BSR / DSR, a long BSR / DSR or a truncated BSR / DSR for XR services, and have corresponding new LCIDs; whereas, in an embodiment herein, the legacy BSR MAC CE is used to carry BSR for non-XR services (or LCs or LCGs). This is illustrated in FIG. 7, which depicts an XR BSR MAC CE format or DSR MAC CE format for carrying at least one delay amount information field, and one buffer size field for the corresponding LCGs configured for XR services. The size of the XR BSR MAC CE or DSR MAC CE can be a variable size (for example, for Long BSR / DSR or Long truncated BSR / DSR format) and a fixed size (for example, for Short BSR / DSR or Short truncated BSR / DSR format). The LCGx (where x is equal to 0 or greater than 0) represents a bit which when set to 1 implies BSR contents (i.e., delay Amount field and / or Buffer Size field) is present for LCGx and when set to 0 implies BSR / DSR contents (i.e., delay Amount field and Buffer Size field) is not present for LCGx.

[0097] In an embodiment herein, a common MAC CE (for example, enhanced BSR MAC CE or DSR MAC CE) can be used to carry buffered data status for XR and non-XR services. That is, MAC CE may include information for LCGs wherein BSR / DSR contents for XR may comprise of at least one of buffered data size field, and delay information field, and include information for LCGs wherein BSR contents for non-XR services may comprise of buffered data size field. The buffered data size field, its interpretation and corresponding tables for data size may vary for XR and non-XR services. This is illustrated in FIG. 8, which depicts an enhanced BSR MAC CE format or DSR MAC CE format for carrying at least one delay amount information field, and one buffer size field for the corresponding LCGs configured for XR services, and for carrying at least one buffer size field for the corresponding LCGs configured for non-XR services. The size of the enhanced BSR MAC CE or DSR MAC CE can be a variable size (for example, for Long BSR / DSR or Long truncated BSR / DSR format) and a fixed size (for example, for Short BSR / DSR or Short truncated BSR / DSR format). The buffer size field for a XR LCG and non-XR LCG may refer to different tables for the buffered data. That is, composing and interpretation for the buffer size field for the XR LCGs and non-XR LCGs may differ. The LCGx (where x is equal to 0 or greater than 0) represents a bit which when set to 1 implies BSR / DSR contents (i.e., delay amount field and / or buffer size field) is present for LCGx and when set to 0 implies BSR / DSR contents (i.e., delay Amount field and Buffer Size field) is not present for LCGx.

[0098] In an embodiment herein, the delay amount field is optional in the BSR / DSR contents. In an embodiment herein, a separate field comprising of a single bit (for example, delayPresence) is used to indicate the presence or absence of the delay amount field for the logical channel group in the BSR / DSR contents. If the value of field delayPresence is one (i.e., set) for a logical channel group, the delay amount field is available for the logical channel group in the BSR contents, and if the value of field delayPresence is zero (i.e., reset) for a logical channel group, the delay amount field is not available for the logical channel group in the BSR / DSR contents. In an embodiment herein, if the field delayPresence is zero (i.e., reset) for a logical channel group, the delay amount field is available for the logical channel group in the BSR / DSR contents, and if the delayPresence is one (i.e. set) for a logical channel group, the delay amount field is not available for the logical channel group in the BSR / DSR contents. In an embodiment herein, the UE 502 includes a field in the BSR / DSR which informs the network 504 the number of logical channel groups for which delayPresence is available. In an embodiment herein, the logical channel groups which have delay amount and the information pertaining to the logical channels with delay amount information are included in the BSR / DSR before including the logical channel groups without delay amount.

[0099] In an embodiment herein, the buffer status and the delay amount are included in the order of priority of the logical channel groups.

[0100] In an embodiment herein, if there are not enough UL resources available for sending both buffer status and delay amount in the BSR / DSR for a logical channel group, the UE 502 includes only the buffer status, provided there is UL resources available for sending the buffer status.

[0101] In an embodiment herein, if there are not enough UL resources available for sending both buffer status, and delay amount in the (enhanced) BSR or DSR for a logical channel group, the UE 502 includes only the delay amount, if there are UL resources available for sending the delay amount for this logical channel group in the BSR / DSR.

[0102] In an embodiment herein, if there are not enough UL resources available for sending both buffer status and delay amount in the (enhanced) BSR or DSR for a logical channel group, the UE 502 skips including both buffer status and the delay amount, for this logical channel group in the BSR even if there are UL resources for sending one of delay amount or buffer status. In an embodiment herein, the UE 502 skips sending BSR / DSR in this case.

[0103] In an embodiment herein, if there are not enough UL resources available for sending both buffer status and delay amount in the enhanced BSR or XR BSR or DSR for all logical channel groups that have accumulated / buffered data, the UE 502 includes at least one of the buffer status and the delay amount for the logical channel groups in the BSR / DSR in their priority order as long as UL resources last.

[0104] In an embodiment herein, the delay information is reported per logical channel instead of logical channel group in the enhanced BSR MAC CE or XR BSR MAC CE or DSR MAC CE. The UE 502 indicates the LCID or eLCID along with the delay information for that logical channel. In an embodiment herein, the enhanced BSR MAC CE or XR BSR MAC CE or DSR MAC CE can be configured per logical channel carrying XR service.

[0105] In an embodiment herein, for Regular and Periodic BSR / DSR, the MAC entity 518 for which logical channel group for XR is configured by upper layers shall:

[0106] 1> if more than one LCG has data available for transmission when the MAC PDU containing the BSR / DSR is to be built:

[0107] 2> report XR Long BSR (or Enhanced Long BSR or Long DSR) for all LCGs which have data available for transmission.

[0108] 1> else:

[0109] 2> report XR short BSR (or Enhanced Short BSR or Short DSR).

[0110] In an embodiment herein, for Padding BSR / DSR, the MAC entity 518 for which logical channel group for XR is configured by upper layers shall:

[0111] 1> if the number of padding bits is equal to or larger than the size of the Short BSR / DSR plus its subheader but smaller than the size of the Long BSR / DSR plus its subheader:

[0112] 2> if more than one LCG has data available for transmission when the BSR / DSR is to be built:

[0113] 3> if the number of padding bits is equal to the size of the Short BSR / DSR plus its subheader:

[0114] 4> report XR Short Truncated BSR (or Enhanced Short Truncated BSR or Short Truncated DSR) of the LCG with the highest priority logical channel with data available for transmission.

[0115] 3> else:

[0116] 4> report XR Long Truncated BSR (or Enhanced Long Truncated BSR or Long Truncated DSR) of the LCG(s) with the logical channels having data available for transmission following a decreasing order of the highest priority logical channel (with or without data available for transmission) in each of these LCG(s), and in case of equal priority, in increasing order of LCGID.

[0117] 2> else:

[0118] 3> report XR Short BSR (or Enhanced Short BSR or Short DSR).

[0119] 1> else if the number of padding bits is equal to or larger than the size of the Long BSR / DSR plus its subheader:

[0120] 2> report XR Long BSR (or Enhanced Long BSR or Long DSR) for all LCGs which have data available for transmission.

[0121] In an embodiment herein, at least one of XR Short BSR / DSR, XR Long BSR / DSR, XR Short Truncated BSR / DSR, XR Long Truncated BSR / DSR, Enhanced Short BSR / DSR, Enhanced Long BSR / DSR, Enhanced Short Truncated BSR / DSR, and Enhanced Long Truncated BSR / DSR are identified and distinguished with a separate LCID and / or eLCID.

[0122] In an embodiment herein, a sample depiction of the ASN structure containing the configuration for XR BSR or enhanced BSR or DSR is shown below:

[0123]

[0124] FIG. 9 depicts an XR BSR MAC CE or DSR MAC CE wherein for a XR LCG there may be zero, one or more BSR / DSR contents (i.e., Delay Amount field and / or Buffer Size field). The LCGx (where x is equal to 0 or greater than 0) represents a bit which when set to 1 implies one or more BSR / DSR contents (i.e., delay Amount field and / or Buffer Size field) is present for LCGx and when set to 0 implies BSR / DSR contents (i.e., delay Amount field and Buffer Size field) is not present for LCGx. The number of BSR / DSR elements field denotes the number of BSR / DSR contents for the pertinent LCG follows in the MAC CE.

[0125] In an embodiment herein, the delay information field can carry a zero or a special reserved value that can be interpreted by the network 504 that the corresponding buffered data size has been discarded by the UE 502.

[0126] In an embodiment herein, the delay information field can carry a zero or a special reserved value that can be interpreted by the network 504 that the corresponding buffered data size is not delay critical.

[0127] In an embodiment herein, the delay information field is not present, and absence of delay information field can be interpreted by the network 504 that the corresponding buffered data size is not delay critical.

[0128] In an embodiment herein, the delay information field can carry a zero or a special reserved value that can be interpreted by the network 504 that the corresponding buffered data size has been buffered recently and delay information is considered to be as remaining duration same as PDB or PSDB.

[0129] In an embodiment herein, the delay information field is not present, and absence of delay information field can be interpreted by the network 504 that the corresponding buffered data size has been buffered recently and delay information is considered to be as remaining duration same as PDB or PSDB.

[0130] In an embodiment herein, the delay amount information is carried in the BSR / DSR using a single bit. The single bit indicates that the data in the logical channel group is delay critical. In an embodiment herein, the delay amount information is carried in the BSR UL MAC CE or DSR MAC CE using two bits which includes a quantized value for the delay or actual delay (or permissible delay etc. as per other embodiments).

[0131] In an embodiment herein, the delay amount information is carried in the BSR UL MAC CE or DSR MAC CE using three bits which includes a quantized value for the delay or actual delay (or permissible delay etc. as per other embodiments). In an embodiment herein, the delay amount information is carried in the BSR UL MAC CE or DSR MAC CE using four bits which includes a quantized value for the delay or actual delay (or permissible delay etc. as per other embodiments). In an embodiment herein, the delay amount information is carried in the BSR UL MAC CE or DSR MAC CE using five bits which includes a quantized value for the delay or actual delay (or permissible delay etc. as per other embodiments). In an embodiment herein, the delay amount information is carried in the BSR UL MAC CE or DSR MAC CE using six bits which includes a quantized value for the delay or actual delay (or permissible delay etc. as per other embodiments). In an embodiment herein, the delay amount information is carried in the BSR UL MAC CE or DSR MAC CE using seven bits which includes a quantized value for the delay or actual delay (or permissible delay etc. as per other embodiments). In an embodiment herein, the delay amount information is carried in the BSR UL MAC CE or DSR MAC CE using eight bits which includes a quantized value for the delay or actual delay (or permissible delay etc. as per other embodiments).

[0132] In an embodiment herein, the UE 502 includes delay amount field only for one or more specific logical channel groups configured by the network 504 for sending delay amount field. In an embodiment herein, the configuration is received from the network (for e.g., gNB) 504 in a RRC message such as RRC Reconfiguration or RRC Resume.

[0133] In an embodiment herein, the enhanced BSR MAC CE or DSR MAC CE is triggered when at least one of the following event is met:

[0134] a) Discard timer(s) for the X number of SDU(s) or PDU Set(s) expires, where X can be an integer equal to 1 or greater than 1. X can be configured by network signaling.

[0135] b) Loss of Y number of SDU(s) or PDU Set (s), where Y can be an integer equal to 1 or greater than 1. Y can be configured by network signaling.

[0136] c) Uplink data, for a logical channel which belongs to an LCG for XR services, becomes available to the MAC entity and either this uplink data belongs to a logical channel with a higher priority than the priority of any logical channel containing available uplink data which belong to any LCG or none of the logical channels which belong to an LCG contains any available uplink data.

[0137] d) Uplink data, for a logical channel which belongs to an LCG for XR services, becomes unavailable (e.g., due to discard at PDCP) to the MAC entity and either this uplink data belongs to a logical channel with a higher priority than the priority of any logical channel containing available uplink data which belongs to any LCG or none of the logical channels which belong to an LCG contains any available uplink data.

[0138] e) retxBSR-Timer expires, and at least one of the logical channels which belong to an LCG for XR services contains UL data.

[0139] f) XR-retxBSR-Timer expires, and at least one of the logical channels which belong to an LCG for XR services contains UL data.

[0140] g) periodicBSR-Timer expires, and the MAC entity is serving XR services.

[0141] h) XR-periodicBSR-Timer expires, and the MAC entity is serving XR services.

[0142] i) the delay of the packet or PDU or PDU set or SDU exceeds a threshold.

[0143] In an embodiment herein, the threshold is provided by the network 504 in RRC signalling. In an embodiment herein, the threshold is configured per logical channel. In an embodiment herein, the threshold is configured per logical channel group. In an embodiment herein, the threshold is configured per PDU set. In an embodiment herein, the threshold is configured within the UE 502, based on standards or algorithms.

[0144] FIG. 10 depicts a procedure 1000 for delay status reporting. In an embodiment herein, the threshold is configured and interpreted as the remaining time threshold. When the remaining time of a packet or PDU or PDU Set or SDU becomes less than its relevant or associated threshold, the MAC entity 518 triggers at least one of enhanced BSR MAC CE and XR BSR MAC CE (or termed as Delay Status Report (DSR)) for delay status reporting. The remaining time is the actual remaining time at the instant when it is reported; i.e., at that instant, enhanced BSR MAC CE or XR BSR MAC CE or DSR MAC CE is transmitted, which includes the relevant data or buffer status. In an embodiment herein, there may be one or more configured remaining time thresholds and they may be indicated by their respective threshold index configured implicitly or explicitly. For example, the threshold index can be derived or interpreted implicitly based on the order of the configured threshold(s) in the RRC signaling message. In another example, an explicit index may be assigned or signaled for the configured threshold(s) in the RRC signaling message.

[0145] In an embodiment herein, the MAC entity 518 reports at least one of the LCG identity or index, configured threshold index, remaining time and data / buffer for the PDU / SDU or PDU Set pertaining to the LCG identity or threshold index or remaining time reported.

[0146] In an embodiment herein, for the case, when PDU Set based discard has been configured for the relevant radio bearer belonging to the logical channel or logical channel group (LCG), the remaining time of the PDU Set is considered. For the PDU Set, the remaining time is determined from the remaining time of the PDCP discardTimer of the first SDU (or at least one SDU) of the PDU Set as different SDUs of the PDU Set may be received at different times by the PDCP layer 520 from application or upper layer and corresponding discardTimer(s) may be running with different values of remaining time. For the data or buffer corresponding to delay status reporting, all the SDUs of the PDU Set are considered (i.e., even if one or more of the SDUs of the PDU Set has remaining time of the PDU set more than the configured remaining time threshold, they are considered for the data or buffer reporting in DSR, if the first SDU (or at least one SDU) of the PDU Set has remaining time of discardTimer lesser than the configured remaining time threshold). Further, the transmitting PDCP entity and / or the MAC entity 518 may consider only the SDUs of the PDU Set that have been received by the PDCP layers and for which discardTimer(s) is / are running; i.e., the data pertaining to the SDU(s) of the PDU Set which is / are not yet received by the PDCP layer 520 is / are not considered.

[0147] In an embodiment herein, for the case, when PDU Set based discard has been configured for the relevant radio bearer belonging to the logical channel or logical channel group (LCG), the remaining time of the PDU Set is considered. For the PDU Set, the remaining time is determined from the remaining time of the PDCP discardTimer of each of the SDU of the PDU Set as different SDUs of the PDU Set may be received at different times by the PDCP layer 520 from application or upper layer and corresponding discardTimer(s) may be running with different values of remaining time. For the data or buffer corresponding to delay status reporting, transmitting PDCP entity and / or the MAC entity 518 may consider those SDUs of the PDU Set for which remaining time of discardTimer has become lesser than the configured remaining time threshold.

[0148] In an embodiment herein, for the case, when PDU Set based discard has not been configured for the relevant radio bearer belonging to the logical channel or logical channel group (LCG), the remaining time of the PDU / SDU is considered. For the data or buffer corresponding to delay status reporting transmitting PDCP entity or the MAC entity 518 may consider the SDU / PDUs for which the remaining time of discardTimer has become lesser than the configured remaining time for threshold.

[0149] In an embodiment herein, for the case, when PDU Set based discard has been configured for at least one first radio bearer, and when PDU Set based discard has not been configured for at least one second radio bearer, the remaining time of the PDU Set of the first radio bearer and the remaining time of the SDU / PDU of the second radio bearer are considered for delay status reporting. The first and second radio bearers belong to the same LCG. Accordingly, the corresponding uplink data (i.e., pertaining to the PDU Set and / or PDU / SDU) is considered for reporting in the delay status report.

[0150] In an embodiment herein, if the MAC entity 518 triggers the at least one of enhanced BSR MAC CE and XR BSR MAC CE (or termed as Delay Status Report (DSR)) for delay status reporting on meeting threshold condition, and the uplink data pertaining to the PDU / SDU or the PSU Set for which the associated PDCP discardTimer(s) is completely expired by the time the DSR MAC CE is transmitted, the MAC entity 518 does not consider the discarded data for delay status reporting in the DSR MAC CE. If all the uplink data pertaining to the delay reporting is discarded by the time DSR MAC CE could be transmitted, the MAC entity 518 cancels the transmission of the DSR MAC CE. If new uplink data gets available pertaining to the delay reporting by the time DSR MAC CE could be transmitted, the MAC entity 518 considers the new uplink data as well to be included for the DSR MAC CE.

[0151] As depicted, the UE 502 is configured for SDU based or PDU Set based discard for each radio bearer in RRC signalling by the network 504, as depicted in step 1002. The UE 502 is configured for a remaining time threshold per LCG (or a logical channel of the LCG) by the network 504, as depicted in step 1004. Thereafter, the UE 502 verifies if the SDU based discard is configured for the relevant radio bearer pertaining to LCG, as depicted in step 1006. If the SDU based discard is not configured for the relevant radio bearer pertaining to LCG, then the UE 502 verifies if the PDU Set based discard is configured for the relevant radio bearer pertaining to LCG, as depicted in step 1008.

[0152] If the SDU based discard is configured for the relevant radio bearer pertaining to LCG, then the UE 502 verifies if the remaining time of the PDU / SDU for the LCG becomes lesser than its associated remaining time threshold, as depicted in step 1010. If the remaining time of the PDU / SDU for the LCG is not lesser than its associated remaining time threshold, then the step of verification of the remaining time of the PDU / SDU for the LCG is repeated.

[0153] If the PDU Set based discard is configured for the relevant radio bearer pertaining to LCG, then the UE 502 verifies if the remaining time of the first PDU / SDU of the PDU Set for the LCG becomes lesser than its associated remaining time threshold, as depicted in step 1012. If the remaining time of the first PDU / SDU of the PDU Set for the LCG is not lesser than its associated remaining time threshold, then the step of verification of the remaining time of the first PDU / SDU of the PDU Set for the LCG is repeated.

[0154] If the remaining time of the PDU / SDU for the LCG is lesser than its associated remaining time threshold, and the remaining time of the first PDU / SDU of the PDU Set for the LCG is lesser than its associated remaining time threshold, then the MAC entity 518 triggers an enhanced BSR MAC CE or XR MAC CE or DSR MAC CE for delay status reporting and indicates at least one of remaining time or configured threshold index and / or the uplink data pertaining to the PDU / SDU and / or PDU Set, as depicted in step 1014.

[0155] The various actions in method 1000 may be performed in the order presented, in a different order or simultaneously. Further, in some embodiments, some actions listed in FIG. 10 may be omitted.

[0156] The congestion activation status or congestion deactivation status for a data radio bearer (DRB) may be provided by PSI-Based SDU discard activation / deactivation MAC CE.

[0157] In an embodiment herein, if the UE 502 is indicated for the congestion condition or activation of the congestion by the network 504, the MAC entity 518 continues reporting of delay status (i.e., the DSR MAC CE) during the congestion.

[0158] In an embodiment herein, if the UE 502 is indicated for the congestion condition or activation of the congestion by the network 504, the MAC entity 518 considers the remaining time of the uplink data for the delay reporting as per the value of discardTimer configured for the uplink data before the congestion activation.

[0159] In an embodiment herein, if the UE 502 is indicated for the congestion condition or activation of the congestion by the network 504, the MAC entity 518 considers the remaining time of the uplink data for the delay reporting as per the value of discardTimer configured for the uplink data after the congestion activation.

[0160] In an embodiment herein, if the UE 502 is indicated for the congestion condition or activation of the congestion by the network 504, the MAC entity 518 stops or suspends reporting of delay status (i.e., the DSR MAC CE) during the congestion.

[0161] In an embodiment herein, if the UE 502 is indicated for the congestion condition or activation of the congestion by the network 504, the MAC entity 518 stops or suspends reporting of delay status (i.e., the DSR MAC CE) during the congestion, for the PDU Sets with a PSI below the configured threshold or configured / determined PSI level. PSI level may be determined based on a UE implementation.

[0162] In an embodiment herein, if the UE 502 is indicated for the congestion condition removal or deactivation of the congestion by the network 504, the MAC entity 518 resumes reporting of delay status (i.e., the DSR MAC CE), for the PDU Sets with a PSI below the configured threshold or configured / determined PSI level. PSI level may be determined based on a UE implementation.

[0163] In an embodiment herein, the enhanced BSR MAC CE (or DSR MAC CE) is triggered when the UE 502 is configured by the network 504 to trigger enhanced BSR MAC CE. In an embodiment herein, the enhanced BSR MAC CE (or DSR MAC CE) is triggered only when there are events for one or more specific logical channel groups configured by the network 504 for sending enhanced BSR MAC CE (or DSR MAC CE). In an embodiment herein, the configuration is received from the network 504 (for example, gNB) in RRC message such as RRC Reconfiguration or RRC Resume.

[0164] In an embodiment herein, the UE 502 informs the network 504 whether it is capable for delay amount reporting. In an embodiment herein, this information is sent in the RRC procedures for UE capability information retrieval. In an embodiment herein, the capability is UE AS capability. In an embodiment herein, a common capability for the XR is used for delay amount reporting.

[0165] In an embodiment herein, a scheduling request is triggered when the regular BSR or DSR is triggered for at least one logical channel (for example, for XR service) irrespective of whether logicalChannelSR-DelayTimer is running or not. This provides for a faster SR triggering for XR. The example specification text is given as below:

[0166] The MAC entity shall:

[0167] 1> if the Buffer Status reporting procedure determines that at least one BSR has been triggered and not cancelled:

[0168] 2> if Uplink Shared Channel (UL-SCH) resources are available for a new transmission and the UL-SCH resources can accommodate the BSR MAC CE plus its subheader as a result of logical channel prioritization:

[0169] 3> instruct the Multiplexing and Assembly procedure to generate the BSR MAC CE(s) as defined in clause 6.1.3.1;

[0170] 3> start or restart periodicBSR-Timer except when all the generated BSRs are long or short Truncated or Extended long or short Truncated BSRs;

[0171] 3> start or restart retxBSR-Timer.

[0172] 2> if a Regular BSR has been triggered for a logical channel for which logicalChannelSR-DelayTimerApplied with value true is configured by upper layers and logicalChannelSR-DelayTimer is not running: or

[0173] 2> if a Regular BSR has been triggered for a logical channel for which logicalChannelSR-DelayTimerApplied with value false is configured by upper layers (e.g., for XR service):

[0174] 3> if there is no UL-SCH resource available for a new transmission; or

[0175] 3> if the MAC entity is configured with configured uplink grant(s) and the Regular BSR was triggered for a logical channel for which logicalChannelSR-Mask is set to false; or

[0176] 3> if the UL-SCH resources available for a new transmission do not meet the Logical Channel Prioritization (LCP) mapping restrictions (see clause 5.4.3.1) configured for the logical channel that triggered the BSR:

[0177] 4> trigger a Scheduling Request.

[0178] In an embodiment herein, a scheduling request is triggered when the regular BSR / DSR is triggered for at least one logical channel for XR service. This is termed as 'BSR for XR' or 'XR BSR' or DSR and corresponding MAC CE is termed as 'XR BSR MAC CE' or DSR MAC CE. XR BSR MAC CE or DSR MAC CE may include at least one of the delay information field and buffered data size field for one or more LCGs. These LCGs pertain to and are configured for XR. The example specification text is given as below:

[0179] The MAC entity shall:

[0180] 1> if the Buffer Status reporting procedure determines that at least one XR BSR has been triggered and not cancelled:

[0181] 2> if UL-SCH resources are available for a new transmission and the UL-SCH resources can accommodate the XR BSR MAC CE plus its subheader as a result of logical channel prioritization:

[0182] 3> instruct the Multiplexing and Assembly procedure to generate the XR BSR MAC CE(s);

[0183] 3> start or restart periodicBSR-Timer (or XR- periodicBSR-Timer) except when all the generated BSRs are long or short Truncated or Extended long or short Truncated BSRs;

[0184] 3> start or restart retxBSR-Timer (or XR-retxBSR-Timer).

[0185] 2> if a Regular BSR has been triggered and logicalChannelSR-DelayTimer is not running:

[0186] 3> if there is no UL-SCH resource available for a new transmission; or

[0187] 3> if the MAC entity is configured with configured uplink grant(s) and the Regular BSR was triggered for a logical channel for which logicalChannelSR-Mask is set to false; or

[0188] 3> if the UL-SCH resources available for a new transmission do not meet the LCP mapping restrictions (see clause 5.4.3.1) configured for the logical channel that triggered the XR BSR:

[0189] 4> trigger a Scheduling Request

[0190] In an embodiment herein, a MAC PDU contains at most one BSR MAC CE or one enhanced BSR MAC CE (or DSR MAC CE), when multiple events have triggered a BSR / DSR and BSR / DSR is commonly signaled as a common MAC CE for XR and non-XR services.

[0191] In an embodiment herein, a MAC PDU contains at most one BSR MAC CE and / or at most one XR BSR MAC CE (or DSR MAC CE), when multiple events have triggered a BSR and / or a XR BSR / DSR and the BSR / DSR is separately signaled as different MAC CEs for XR and non-XR services.

[0192] In an embodiment herein, If a Hybrid Automatic Repeat reQuest (HARQ) process is configured with cg-RetransmissionTimer and if the BSR / DSR is already included in a MAC PDU for transmission on configured grant by this HARQ process, but not yet transmitted by lower layers, then the UE 502 updates the BSR / DSR contents (for example, enhanced BSR MAC CE or XR BSR MAC CE or DSR MAC CE) with the latest delay information and / or the buffered data status.

[0193] In an embodiment herein, for BSR / DSR triggered by retxBSR-Timer expiry, the MAC entity considers that the logical channel that triggered the BSR / DSR is the highest priority logical channel that has data available for transmission at the time the BSR / DSR is triggered, except when the data becomes unavailable for example, due to packet discard or packet loss or exceeding delay limit. In this case, at least one of the following is performed: the BSR / DSR is cancelled or the BSR / DSR with zero buffered data size is reported.

[0194] In an embodiment herein, at least one triggered BSR / DSR may be cancelled when data (for example, for XR service) becomes unavailable due to SDU or PDU Set discard upon discard timer expiry or loss of packets.

[0195] In an embodiment herein, at least one triggered BSR / DSR may not be cancelled when data (for example, for XR service) becomes unavailable due to SDU or PDU Set discard upon discard timer expiry or loss of packets. BSR / DSR is signaled to the network 504 in this case to inform the update of buffer status (i.e., becoming empty). BSR / DSR therefore may be a zero BSR / DSR i.e., carrying the buffered data size is zero.

[0196] In an embodiment herein, at least one BSR / DSR triggered priori to MAC PDU assembly may be cancelled when a MAC PDU is transmitted. This PDU includes a Long, Extended Long, Short, or Extended Short BSR / DSR MAC CE, Enhanced Short BSR / DSR MAC CE, and Enhanced Long BSR / DSR MAC CE which contains buffer status up to (and including) the last event that triggered a BSR / DSR prior to the MAC PDU assembly.

[0197] In an embodiment herein, LCGs and / or LCs for XR and non-XR services are distinguished based on the configuration. For example, RRC reconfiguration message carrying configuration for bearer and logical channel carry at least a field that signifies which LCG and / or LC is XR related or non-XR related.

[0198] FIG. 11 depicts a sample structure of Short Delay reporting BSR / DSR MAC CE carrying the (average and / or least) 5-bit delay information of PDU set / PDU in that LCG.

[0199] FIG. 12 depicts a sample structure of Short Delay reporting BSR / DSR MAC CE carrying the (average and / or least) 3-bit delay information of PDU set / PDU in that LCID.

[0200] FIG. 13 depicts a sample structure of Long Delay reporting BSR / DSR MAC CE carrying the (average and / or least) 8-bit delay information of PDU set / PDU in that LCG.

[0201] FIG. 14 depicts a sample structure of enhanced common BSR / DSR MAC CE carrying the (average and / or least) delay information or buffer status. Table 1 indicates field description for the delay information or buffer size information.

[0202] Field Description: If the D / B field indicates if the enhanced BSR (or DSR) carries only delay information or buffer size information or bothB / Di FieldInterpretation00Carries Buffer size information only for ith LCG01Carries Delay information only for ith LCG10Carries both Delay and Buffer size information for ith LCG11Reserved

[0203] In an embodiment herein, when enhanced BSR MAC CE or XR BSR MAC CE or DSR MAC CE is included in the message 1 (msg1) or message 3 (msg3) in the random access procedure, and there is retransmission of msg1 or msg3, the enhanced BSR MAC CE or XR BSR MAC CE or DSR MAC CE may be included with updating the BSR contents (for example, delay information and / or buffered data size).

[0204] In an embodiment herein, the PDCP entity associated with an XR Radio bearer and / or PDCP entity configured by network 504 to calculate the delay information, calculates the delay information used for generation of XR BSR or enhanced BSR / DSR for delay reporting. The PDCP entity may calculate one or more delay information for the buffered data. The transmitting entity of PDCP calculates one or combination of the following delay information:

[0205] - Delay calculated as time elapsed since reception of the first PDCP SDU in the buffer yet to be processed by PDCP entity;

[0206] - Remaining time in delay budget associated with the first PDCP SDU in the buffer yet to be processed by the PDCP entity;

[0207] - Remaining delay budget associated with the PDU Set to which first PDCP SDU in the buffer belongs to and is yet to be processed by the PDCP entity;

[0208] - Average delay associated with the PDCP SDUs yet to be processed by the PDCP entity; and

[0209] - Average delay associated with the PDCP PDUs yet to be submitted to lower layers.

[0210] In an embodiment herein, the PDCP entity indicates at least one of or combination of the calculated value to MAC entity 518 for delay BSR (or DSR),

[0211] - the average delay of the PDCP SDUs in the buffer, and / or

[0212] - the average remaining delay budget for the PDCP SDUs / PDUs in the buffer, and / or

[0213] - the delay associated with the PDCP SDU / PDU which has the maximum delay among the SDUs in the buffer, and / or

[0214] - the minimum remaining delay budget for the SDUs / PDUs in the buffer.

[0215] In an embodiment herein, the RLC entity associated with a logical channel serving XR service and / or is configured by the network 504 to calculate the delay information used for generating XR BSR or enhanced BSR or DSR. The RLC entity may calculate one or more delay information for the buffered data. The transmitting RLC entity calculates one or combination of the following:

[0216] - Delay incurred by the first RLC SDU yet to be processed by the RLC entity

[0217] - Delay incurred by the first RLC PDU or RLC PDU segment yet to be allocated with a UL grant for initial transmission

[0218] - Delay incurred by the first RLC PDU or RLC PDU segment yet to be allocated with a UL grant for retransmission

[0219] - Average delay incurred by the RLC SDUs in the buffer yet to be processed by the RLC entity

[0220] - Average delay incurred by the RLC PDU or RLC PDU segments in buffer yet to be allocated with a UL grant for initial transmission

[0221] - Average delay incurred by the RLC PDUs or RLC PDU segments in buffer yet to be allocated with a UL grant for retransmission

[0222] In another embodiment herein, the network 504 configures the UE 502 on which of the delay quantities the PDCP / RLC entities has to measure as part of

[0223] - Radio bearer configuration and / or

[0224] - Logical channel Configuration and / or

[0225] - BSR configuration and / or

[0226] - XR specific BSR configuration for delay reporting.

[0227] In an embodiment herein, data volume calculation for the purpose XR BSR or enhanced BSR or DSR is performed at the transmitting PDCP entity to determine PDCP data volume and at the transmitting RLC entity to determine RLC data volume. PDCP data volume and / or RLC data volume may be categorized to one or more delay values or range of delay values for example, one or more range of delay values formed as between x percent and y percent or fraction of the packet delay budget or PDU Set delay budget. For example, four ranges can be: (a) less than 25%, (b) 25% to less than 50%, (c) 50% to less than 75% and (d) 75% to 100% of PDB or PSDB. Data volume thus can be accounted under respective range of delays based on the delay encountered since the SDU / PDU / PDU Set or PDU Sets is buffered at PDCP buffer. The PDCP entity provides the delay information to the RLC entity when the SDU / PDU / PDU Set is passed to the RLC entity, so that RLC entity can start from this given value of the delay and account for further delay in the RLC buffer. The PDCP entity and / or RLC entity indicate the calculated data volume and the pertinent delay values or range of delay values to the MAC entity 518 for example, when the MAC entity 518 needs to compose and send the XR BSR MAC CE or enhanced BSR MAC CE or DSR MAC CE. In an alternative embodiment, delay value or range of delay values can be the remaining duration to the expiry of the pertinent discard timer or completion of the PDB or PSDB.

[0228] In an embodiment herein, for the PDCP data volume calculation for the Acknowledged Mode (AM) Data Radio Bearers (DRBs), the PDCP SDUs to be retransmitted and / or the PDCP Data PDUs to be retransmitted may also be considered. For these data volume calculation, the delay value or the range of delay values is accounted from the time when these data are buffered in the PDCP buffer from the application for the first transmission.

[0229] In an embodiment herein, in case of PDCP duplication with activated state, same delay amount is considered while calculating the PDCP data volume for both the MAC entities associated with primary RLC entity and the RLC entity other primary RLC entity.

[0230] In an embodiment herein, for the RLC data volume calculation for the Acknowledged Mode (AM) Data Radio Bearers (DRBs), the RLC data PDUs that are pending for retransmission may also be considered. For these data volume calculation, the delay value or the range of delay values is accounted from the time when these data were buffered in the PDCP buffer from the application for the first transmission.

[0231] Further, in the next few paragraphs, examples for the 3GPP specification for the DSR procedure are described, also addressing the proposed embodiments.

[0232] For example, the DSR procedure is used to provide the serving gNB with delay status of LCGs. This delay status for an LCG includes remaining time, which is the smallest remaining value of the running PDCP discardTimer among PDCP SDUs that are buffered for the LCG but have not been transmitted in any MAC PDU as specified in clause 7.3 in TS 38.323 [4], and the total amount of delay-critical UL data for the LCG according to the data volume calculation procedure specified in clause 5.5 in TS 38.322 [3] and clause 5.15 in TS 38.323 [4] for the associated RLC and PDCP entities, respectively.

[0233] For example, RRC controls the DSR procedure by configuring the following parameter:

[0234] - remainingTimeThreshold (per LCG): the threshold on remaining time for triggering a DSR for a logical channel within an LCG.

[0235] For example, If an LCG is configured for delay status reporting, the MAC entity 518 shall for each logical channel within the LCG:

[0236] 1> if the smallest remaining value of the running PDCP discardTimer among all the PDCP SDUs buffered for the logical channel that have not been transmitted in any MAC PDU and have not been reported as data volume in a DSR MAC CE becomes below remainingTimeThreshold of the LCG; and

[0237] 1> if there is no DSR pending for the logical channel:

[0238] 2> trigger a DSR for the logical channel.

[0239] If there is at least one DSR pending, the MAC entity 518 shall:

[0240] 1> if UL-SCH resources are available for a new transmission and the UL-SCH resources can accommodate the DSR MAC CE plus its subheader as a result of logical channel prioritization:

[0241] 2> instruct the Multiplexing and Assembly procedure to generate the DSR MAC CE as specified in clause 6.1.3.72.

[0242] 1> else if there is no pending SR already triggered by the DSR procedure for the same logical channel as of this DSR:

[0243] 2> trigger a Scheduling Request.

[0244] NOTE: The availability of UL-SCH resources for the transmission of the DSR MAC CE follows the same criteria specified in clause 5.4.5.

[0245] For example, a PDCP SDU is considered to be associated with a DSR if it has not been transmitted in any MAC PDU and is a delay-critical PDCP SDU (as defined in TS38.323) associated with the logical channel which triggered the DSR.

[0246] For example, a MAC PDU shall contain at most one DSR MAC CE. A MAC PDU shall not contain a DSR MAC CE if it includes all PDCP SDUs associated with all the pending DSRs.

[0247] For example, after a DSR is triggered, it is considered as pending until it is cancelled. The MAC entity 518 shall cancel a pending DSR, when all the PDCP SDUs associated with the DSR have been discarded, or when a MAC PDU is transmitted and this MAC PDU includes a DSR MAC CE that contains the delay information of all the PDCP SDUs associated with the DSR (as described in the clause 6.1.3.72), or when a MAC PDU is transmitted and this MAC PDU includes all the PDCP SDUs associated with the DSR.

[0248] NOTE: It is up to UE implementation whether the MAC entity 518 includes a DSR MAC CE in a MAC PDU if the MAC PDU can accommodate all PDCP SDUs associated with all the pending DSRs but is not sufficient to additionally accommodate the DSR MAC CE plus its subheader.

[0249] For example, the DSR MAC CE is identified by MAC subheader with an eLCID as specified in Table 6.2.1-2b.

[0250] For example, the fields in the DSR MAC CE are defined as follows:

[0251] - LCGi: This field indicates the presence of delay information (i.e., the Remaining Time and Buffer Size fields) for the LCGi. The LCGi field set to 1 indicates that the delay information for the LCGi is reported. The LCGi field set to 0 indicates that the delay information for the LCGi is not reported;

[0252] - Remaining Time: This field indicates the shortest remaining value of running PDCP discardTimer (described in clause 7.3 in TS 38.323 [4]) among all PDCP SDUs that are buffered for an LCG but have not been transmitted in any MAC PDU, at the time of the first symbol of the first PUSCH transmission that includes this DSR MAC CE. The length of this field is 6 bits. This field is present only if the buffer size indicated by the corresponding Buffer Size field is not zero; otherwise, this field is reserved and set to 0. If present, the value r in this field indicates a remaining time within the range of (r, r + 1) msec;

[0253] - BT: This field is present only if corresponding LCG is configured with additionalBS-TableAllowed and the buffer size indicated by the corresponding Buffer Size field is not zero; otherwise, this field is reserved and set to 0. If present, the BT field set to 1 indicates that the buffer sizes specified in Table 6.1.3.1-3 are used to set the value of the Buffer Size field, while the BT field set to 0 indicates that the buffer sizes specified in Table 6.1.3.1-2 are used instead;

[0254] - Buffer Size: The Buffer Size field indicates the total amount of delay-critical UL data for an LCG according to the data volume calculation procedure specified in clause 5.5 in TS 38.322 [3] and clause 5.6 in TS 38.323 [4] for the associated RLC and PDCP entities, respectively, after the MAC PDU has been built. If the corresponding LCG is configured with additionalBS-TableAllowed and the amount of delay-critical UL data for an LCG is within the buffer sizes specified in Table 6.1.3.1-3, the MAC entity 518 shall use the buffer sizes specified in Table 6.1.3.1-3 to set the value of this field; otherwise, the MAC entity 518 shall use Table 6.1.3.1-2 instead. This field is indicated in number of bytes. The length of this field is 8 bits.

[0255] For example, the DSR MAC CE, as depicted in FIG. 15, shall include delay information of all LCGs which have pending DSRs when the MAC PDU containing this DSR MAC CE is to be built. The Remaining Time, the BT, and the Buffer Size fields for an LCG shall be reported in two consecutive octets. These three fields for different LCGs shall be included in a DSR MAC CE in ascending order based on the LCGi.

[0256] Delay-critical PDCP SDU: if pdu-SetDiscard is not configured, a PDCP SDU for which the remaining time till discardTimer expiry is less than the remainingTimeThreshold. If pdu-SetDiscard is configured, a PDCP SDU belonging to a PDU Set of which at least one PDCP SDU has the remaining time till discardTimer expiry less than the remainingTimeThreshold.

[0257] For example, at reception of a PDCP SDU from upper layers, the transmitting PDCP entity shall:

[0258] - if discardTimerForLowImportance is configured and PSI based SDU discard is activated, and the PDCP SDU belongs to a low importance PDU Set:

[0259] - start the discardTimerForLowImportance associated with this PDCP SDU;

[0260] - else:

[0261] - start the discardTimer associated with this PDCP SDU (if configured).

[0262] NOTE 0: Identification of PSI of a PDU Set and determination of low importance PDU Set are left up to UE implementation.

[0263] The purpose of MAC delay status reporting, the transmitting PDCP entity shall consider the following as delay-critical PDCP data volume:

[0264] - the delay-critical PDCP SDUs for which no PDCP Data PDUs have been constructed;

[0265] - the PDCP Data PDUs that contain the delay-critical PDCP SDUs and have not been submitted to lower layers;

[0266] - the PDCP Control PDUs;

[0267] - for AM DRBs, the PDCP SDUs to be retransmitted according to clause 5.1.2 and clause 5.13;

[0268] - for AM DRBs, the PDCP Data PDUs to be retransmitted according to clause 5.5.

[0269] In an embodiment herein, the MAC entity 518 may cancel the triggered Delay Status Reporting procedure upon resetting the MAC. In an embodiment herein, the MAC entity 518 may cancel the triggered Delay Status Reporting procedure upon the MAC reset when the MAC reset is triggered due to various reasons including, but not limiting to, based on a request from upper layers, a Layer Triggered Mobility (LTM) cell switch, ReconfigurationWithSync, a Secondary Cell Group (SCG) deactivation, and so on. FIG. 16 illustrates a method 1600 for DSR handling during MAC Reset.

[0270] As depicted in step 1602, the DSR procedure is triggered by the MAC entity 518. Thereafter, on receiving a MAC reset request from the upper layers of the UE 502, the MAC entity 518 performs a MAC reset, as depicted in step 1604. The MAC entity 518 cancels the triggered DSR procedure, upon resetting the MAC, as depicted in step 1606.

[0271] The various actions in method 1600 may be performed in the order presented, in a different order or simultaneously. Further, in some embodiments, some actions listed in FIG. 16 may be omitted.

[0272] In an embodiment herein, if the reset of the MAC entity 518 is requested by upper layers or the reset of the MAC entity 518 is triggered due to SCG deactivation as defined in clause 5.29 or the reset of the MAC entity 518 is triggered due to LTM cell switch, then the MAC entity 518 may perform the following procedure:

[0273] 1> if the MAC reset is not due to SCG deactivation:

[0274] 2> initialize Bj for each logical channel to zero;

[0275] 1> initialize SBj for each logical channel to zero if Sidelink resource allocation mode 1 is configured by RRC;

[0276] 1> if upper layers indicate SCG deactivation and bfd-and-RLM with value true is configured for the deactivated SCG:

[0277] 2> stop (if running) all timers except beamFailureDetectionTimer associated with PSCell and timeAlignmentTimers.

[0278] 1> else:

[0279] 2> stop (if running) all timers, except MBS broadcast DRX timers;

[0280] 2> consider all timeAlignmentTimers, inactivePosSRS-TimeAlignmentTimer, and cg-SDT-TimeAlignmentTimer, if configured, as expired and perform the corresponding actions in clause 5.2;

[0281] 1> set the NDIs for all uplink HARQ processes to the value 0;

[0282] 1> sets the NDIs for all HARQ process IDs to the value 0 for monitoring PDCCH in Sidelink resource allocation mode 1;

[0283] 1> stop, if any, ongoing Random Access procedure;

[0284] 1> discard explicitly signalled contention-free Random Access Resources for 4-step RA type and 2-step RA type and also for LTM candidate cell, if any;

[0285] 1> flush Msg3 buffer;

[0286] 1> flush MSGA buffer;

[0287] 1> cancel, if any, triggered Scheduling Request procedure;

[0288] 1> cancel, if any, triggered Buffer Status Reporting procedure;

[0289] 1> cancel, if any, triggered Power Headroom Reporting procedure;

[0290] 1> cancel, if any, triggered consistent Listen-Before-Talk (LBT) failure;

[0291] 1> cancel, if any, triggered BFR;

[0292] 1> cancel, if any, triggered Sidelink Buffer Status Reporting procedure;

[0293] 1> cancel, if any, triggered Pre-emptive Buffer Status Reporting procedure;

[0294] 1> cancel, if any, triggered Timing Advance Reporting procedure;

[0295] 1> cancel, if any, triggered Recommended bit rate query procedure;

[0296] 1> cancel, if any, triggered Configured uplink grant confirmation;

[0297] 1> cancel, if any, triggered configured sidelink grant confirmation;

[0298] 1> clear, if any, configured sidelink grants;

[0299] 1> cancel, if any, triggered Desired Guard Symbol query;

[0300] 1> cancel, if any, triggered Positioning Measurement Gap Activation / Deactivation Request procedure;

[0301] 1> cancel, if any, triggered SDT procedure;

[0302] 1> cancel, if any, triggered Integrated Access Backhaul-Mobile Terminal (IAB-MT) Recommended Beam Indication query;

[0303] 1> cancel, if any, triggered Desired DL TX Power Adjustment query;

[0304] 1> cancel, if any, triggered Desired IAB-MT PSD range query;

[0305] 2> cancel, if any, triggered Case-6 Timing Request query;

[0306] 1> cancel, if any, triggered Delay Status Reporting procedure;

[0307] 2> flush the soft buffers for all DL HARQ processes, except for the DL HARQ process being used for MBS broadcast;

[0308] 1> for each DL HARQ process, except for the DL HARQ process being used for MBS broadcast, consider the next received transmission for a TB as the very first transmission;

[0309] 1> release, if any, Temporary Cell Radio Network Temporary Identifier (C-RNTI);

[0310] 1> if upper layers indicate SCG deactivation and bfd-and-RLM with value true is not configured; or

[0311] 1> if the MAC reset is not due to SCG deactivation:

[0312] 2> reset all BFI_COUNTERs;

[0313] 1> reset all LBT_COUNTERs.

[0314] In an embodiment herein, the MAC entity 518 may cancel the triggered DSR procedure upon the discard of PDU(s) or PDU Set(s). In an example, the discard as mentioned in the present disclosure refers to the discard of PDUs or PDU Sets as performed by PDCP layer 520 in the UE 502 based on timer or PDU Set importance or any other conditions. In an embodiment herein, the MAC entity 518 may cancel the triggered DSR upon the discard of PDU(s) or PDU set(s) and the remaining time of the available PDU(s) after discard or the available PDU Set(s) after discard in an LCG, for which DSR is triggered, is not shorter than its associated / configured remainingTimeThreshold.

[0315] In an embodiment herein, the MAC entity 518 may cancel triggered DSR procedure for a LCG, if the associated LCG is reconfigured. In an embodiment herein, the MAC entity 518 may cancel the triggered DSR procedure for a LCG, if the remainingTimeThreshold for the LCG is modified by the network 504 through an RRC message such as RRCReconfiguration message or RRCResume message. In an embodiment herein, the MAC entity 518 may cancel the triggered DSR for a LCG if it receives enough grants to transmit all the PDU(s) or PDU set(s) for the LCG. In an embodiment herein, the MAC entity 518 may cancel the triggered DSR for LCG if it receives enough grants to transmit all the PDU(s) or PDU set(s) for the LCG for which the remaining time is shorter than remainingTimeThreshold.

[0316] In an embodiment herein, upon the discard of PDU(s) or PDU Set(s), if the DSR contains delay information for the UL data from multiple LCG(s) and the remaining time of the available UL PDU(s) after discard or the available UL PDU Set(s) after discard for all those LCG(s) for which DSR is triggered, is not shorter than its associated remainingTimeThreshold, the UE 502 cancels the triggered DSR procedure for those LCG(s).

[0317] In an embodiment herein, the MAC entity 518 cancels triggered DSR procedure upon the discard of PDU(s) or PDU Set(s), if there is no UL data available in an LCG for which DSR is configured.

[0318] In an embodiment herein, upon the discard of PDU(s) or PDU Set(s), if DSR contains delay information for the data from multiple LCG(s), the UE 502 cancels the triggered DSR procedure if there is no UL data available in all those LCG(s).

[0319] In an embodiment herein, if there is no UL data (PDU / PDU set) available at the time of transmission of DSR in an LCG for which DSR is triggered, the UE 502 cancels the triggered DSR procedure. In an embodiment herein, if there is no UL data (PDU / PDU set) available at the time of transmission of DSR, in all the LCG(s) for which the DSR is triggered, the UE 502 cancels the triggered DSR.

[0320] In an embodiment herein, if there is no UL data (PDU / PDU set) available at the time of transmission of DSR in all the LCG(s) for which DSR is configured, the UE 502 cancels the triggered DSR procedure.

[0321] In an embodiment herein, if there is no UL data available in an LCG at the time of transmission of DSR for which DSR is triggered such that the remaining time of the data (PDU / PDU set) in the LCG is shorter than the associated remainingTimeThreshold, the UE 502 cancels the triggered DSR procedure.

[0322] In an embodiment herein, if there is no UL data (PDU / PDU set) available at the time of transmission of DSR, in all the LCG(s) for which the DSR is triggered, such that the remaining time of the data (PDU / PDU set) in any of those LCG(s) is shorter than the associated remainingTimeThreshold(s), the UE 502 cancels the triggered DSR.

[0323] In an embodiment herein, if there is no UL data (PDU / PDU set) available at the time of transmission of DSR, in all the LCG(s) for which DSR is configured, such that the remaining time of the data (PDU / PDU set) in any of those LCG(s) is shorter than the associated remainingTimeThreshold(s), the UE 502 cancels the triggered DSR.

[0324] In an embodiment herein, the MAC entity 518 may cancel the triggered buffer status report upon the discard of PDU or PDU set.

[0325] In an embodiment herein, the MAC entity 518 may cancel the triggered SL-PRS resource request upon MAC Reset, i.e., the MAC entity 518 may cancel the triggered SL-PRS resource request upon the MAC reset.

[0326] FIG. 17 illustrates a method 1700 for DSR handling during SDU / PDU set discard. As depicted in step 1702, the DSR procedure is triggered by the MAC entity 518. If PDU or PDU Set is discarded, the MAC entity 518 identifies remaining time of available PDU / PDU set, whether the remaining time of available PDU / PDU set is above DSR reporting threshold, as depicted in step 1704. If so, the MAC entity 518 cancels transmission of the DSR procedure, as depicted in step 1706.

[0327] The various actions in method 1700 may be performed in the order presented, in a different order or simultaneously. Further, in some embodiments, some actions listed in FIG. 17 may be omitted.

[0328] FIG. 18 illustrates a method 1800 for a SL-PRS resource request handling during MAC reset. As depicted in step 1802, the SL-PRS resource request is triggered by the MAC entity 518. Thereafter, on receiving a MAC reset request from the upper layers of the UE 502, the MAC entity 518 performs a MAC reset, as depicted in step 1804. The MAC entity 518 cancels the triggered SL-PRS resource request, upon resetting the MAC, as depicted in step 1806.

[0329] The various actions in method 1800 may be performed in the order presented, in a different order or simultaneously. Further, in some embodiments, some actions listed in FIG. 18 may be omitted.

[0330] In an embodiment herein, if the reset of the MAC entity 518 is requested by upper layers or the reset of the MAC entity 518 is triggered due to SCG deactivation as defined in clause 5.29 or the reset of the MAC entity 518 is triggered due to LTM cell switch, the MAC entity 518 may perform the following procedure:

[0331] 1> if the MAC reset is not due to SCG deactivation:

[0332] 2> initialize Bj for each logical channel to zero;

[0333] 1> initialize SBj for each logical channel to zero if Sidelink resource allocation mode 1 is configured by RRC;

[0334] 1> if upper layers indicate SCG deactivation and bfd-and-RLM with value true is configured for the deactivated SCG:

[0335] 2> stop (if running) all timers except beamFailureDetectionTimer associated with PSCell and timeAlignmentTimers.

[0336] 1> else:

[0337] 2> stop (if running) all timers, except MBS broadcast DRX timers;

[0338] 2> consider all timeAlignmentTimers, inactivePosSRS-TimeAlignmentTimer, and cg-SDT-TimeAlignmentTimer, if configured, as expired and perform corresponding actions in clause 5.2;

[0339] 1> set the NDIs for all uplink HARQ processes to the value 0;

[0340] 1> sets the NDIs for all HARQ process IDs to the value 0 for monitoring PDCCH in Sidelink resource allocation mode 1;

[0341] 1> stop, if any, ongoing Random Access procedure;

[0342] 1> discard explicitly signalled contention-free Random Access Resources for 4-step RA type and 2-step RA type and also for LTM candidate cell, if any;

[0343] 1> flush Msg3 buffer;

[0344] 1> flush MSGA buffer;

[0345] 1> cancel, if any, triggered Scheduling Request procedure;

[0346] 1> cancel, if any, triggered Buffer Status Reporting procedure;

[0347] 1> cancel, if any, triggered Power Headroom Reporting procedure;

[0348] 1> cancel, if any, triggered consistent LBT failure;

[0349] 1> cancel, if any, triggered BFR;

[0350] 1> cancel, if any, triggered Sidelink Buffer Status Reporting procedure;

[0351] 1> cancel, if any, triggered Pre-emptive Buffer Status Reporting procedure;

[0352] 1> cancel, if any, triggered Timing Advance Reporting procedure;

[0353] 1> cancel, if any, triggered Recommended bit rate query procedure;

[0354] 1> cancel, if any, triggered Configured uplink grant confirmation;

[0355] 1> cancel, if any, triggered configured sidelink grant confirmation;

[0356] 1> clear, if any, configured sidelink grants;

[0357] 1> cancel, if any, triggered Desired Guard Symbol query;

[0358] 1> cancel, if any, triggered Positioning Measurement Gap Activation / Deactivation Request procedure;

[0359] 1> cancel, if any, triggered SDT procedure;

[0360] 1> cancel, if any, triggered IAB-MT Recommended Beam Indication query;

[0361] 1> cancel, if any, triggered Desired DL TX Power Adjustment query;

[0362] 2> cancel, if any, triggered Desired IAB-MT PSD range query;

[0363] 1> cancel, if any, triggered Case-6 Timing Request query;

[0364] 1> cancel, if any, triggered Delay Status Reporting procedure;

[0365] 1> cancel, if any triggered SL-PRS Resource Request;

[0366] 1> flush the soft buffers for all DL HARQ processes, except for the DL HARQ process being used for MBS broadcast;

[0367] 1> for each DL HARQ process, except for the DL HARQ process being used for MBS broadcast, consider the next received transmission for a TB as the very first transmission;

[0368] 1> release, if any, Temporary C-RNTI;

[0369] 1> if upper layers indicate SCG deactivation and bfd-and-RLM with value true is not configured; or

[0370] 1> if the MAC reset is not due to SCG deactivation:

[0371] 2> reset all BFI_COUNTERs;

[0372] 1> reset all LBT_COUNTERs.

[0373] In an embodiment herein, the MAC entity 518 for DSR may have higher priority than MAC CE for SL-PRS resource request during logical channel prioritization. In an embodiment herein, the MAC CE for DSR has higher priority than the MAC CE for (Enhanced) Single Entry Power Headroom Reporting (PHR), or the MAC CE for (Enhanced) Multiple Entry PHR and has a lower priority than MAC CE for (Extended) BSR, with exception of BSR included for padding, during logical channel prioritization. In an embodiment herein, the MAC CE for SL-PRS resource request may have higher priority than the MAC CE for Positioning Measurement Gap Activation / Deactivation Request and has a lower priority than the MAC CE for (Enhanced) Single Entry PHR, or the MAC CE for (Enhanced) Multiple Entry PHR, during logical channel prioritization.

[0374] In an example, one or more of the above embodiments may be represented as below in 3GPP specification TS 38.321.

[0375] Logical channels may be prioritized in accordance with the following order (highest priority listed first):

[0376] - MAC CE for C-RNTI, or data from Uplink-Common Control Channel (UL-CCCH);

[0377] - MAC CE for (Enhanced) BFR, or MAC CE for Configured Grant Confirmation, or MAC CE for Multiple Entry Configured Grant Confirmation;

[0378] - MAC CE for Sidelink Configured Grant Confirmation;

[0379] - MAC CE for LBT failure;

[0380] - MAC CE for Timing Advance Report;

[0381] - MAC CE for SL-BSR prioritized according to clause 5.22.1.6;

[0382] - MAC CE for (Extended) BSR, with exception of BSR included for padding;

[0383] - MAC CE for Delay Status Reporting;

[0384] - MAC CE for (Enhanced) Single Entry PHR, or MAC CE for (Enhanced) Multiple Entry PHR;

[0385] - MAC CE for SL-PRS Resource Request

[0386] - MAC CE for Positioning Measurement Gap Activation / Deactivation Request;

[0387] - MAC CE for the number of Desired Guard Symbols;

[0388] - MAC CE for Case-6 Timing Request;

[0389] - MAC CE for (Extended) Pre-emptive BSR;

[0390] - MAC CE for SL-BSR, with exception of SL-BSR prioritized according to clause 5.22.1.6 and SL-BSR included for padding;

[0391] - MAC CE for IAB-MT Recommended Beam Indication, or MAC CE for Desired IAB-MT PSD range, or MAC CE for Desired DL Tx Power Adjustment;

[0392] - data from any Logical Channel, except data from UL-CCCH;

[0393] - MAC CE for Recommended bit rate query;

[0394] - MAC CE for BSR included for padding;

[0395] - MAC CE for SL-BSR included for padding.

[0396] In an alternate embodiment, the MAC CE for SL-PRS resource request may have higher priority than the MAC CE for DSR during logical channel prioritization.

[0397] In an alternate embodiment, the MAC CE for DSR may have higher priority than the MAC CE for (Extended) BSR, with exception of BSR included for padding MAC CE and a lower priority than the MAC CE SL BSR, during logical channel prioritization.

[0398] In an alternate embodiment, the MAC CE for Positioning Measurement Gap Activation / Deactivation Request has higher priority than MAC CE for SL-PRS Resource Request, during logical channel prioritization.

[0399] In an alternate embodiment, the MAC CE for SL-PRS Resource Request has a higher priority than the MAC CE for the number of Desired Guard Symbols, during logical channel prioritization.

[0400] In an embodiment herein, the MAC CE for DSR may be considered as higher priority than MAC CE for SL-PRS resource request during logical channel prioritization. If the UE 502 has both the MAC CE for DSR and the MAC CE for SL-PRS resource request and it is able to transmit only one of them (for e.g., due to resource limitations), the UE 502 may transmit the MAC CE for DSR.

[0401] In an alternate embodiment, the MAC CE for DSR may be considered as lower priority than the MAC CE for SL-PRS resource request during logical channel prioritization.

[0402] The proposed methods 600 focus on various UE actions performed for DSR procedure for XR or triggered SL-PRS resource request. Specifically, the methods 600 focus on the problem of how the delay status report procedure and the SL-PRS resource request maybe cancelled, and how the logical channel prioritization between DSR and SL-PRS resource request may be performed.

[0403] The embodiments disclosed herein can be implemented through at least one software program running on at least one hardware device and performing network management functions to control the network elements. The elements include blocks which can be at least one of a hardware device, or a combination of hardware device and software module.

[0404] The foregoing description of the specific embodiments will so fully reveal the general nature of the embodiments herein that others can, by applying current knowledge, readily modify and / or adapt for various applications such specific embodiments without departing from the generic concept, and, therefore, such adaptations and modifications should and are intended to be comprehended within the meaning and range of equivalents of the disclosed embodiments. It is to be understood that the phraseology or terminology employed herein is for the purpose of description and not of limitation. Therefore, while the embodiments herein have been described in terms of embodiments and examples, those skilled in the art will recognize that the embodiments and examples disclosed herein can be practiced with modification within the scope of the embodiments as described herein.

[0405] A reference to an element in the singular is not intended to mean one and only one unless specifically so stated, but rather one or more. For example, "a" module may refer to one or more modules. An element proceeded by "a," "an," "the," or "said" does not, without further constraints, preclude the existence of additional same elements.

[0406] Headings and subheadings, if any, are used for convenience only and do not limit the disclosure. The word exemplary is used to mean serving as an example or illustration. To the extent that the term "include," "have," or the like is used, such term is intended to be inclusive in a manner similar to the term "comprise" as "comprise" is interpreted when employed as a transitional word in a claim. Relational terms such as first and second and the like may be used to distinguish one entity or action from another without necessarily requiring or implying any actual such relationship or order between such entities or actions.

[0407] Phrases such as an aspect, the aspect, another aspect, some aspects, one or more aspects, an implementation, the implementation, another implementation, some implementations, one or more implementations, an embodiment, the embodiment, another embodiment, some embodiments, one or more embodiments, a configuration, the configuration, another configuration, some configurations, one or more configurations, the subject technology, the disclosure, the present disclosure, other variations thereof and alike are for convenience and do not imply that a disclosure relating to such phrase(s) is essential to the subject technology or that such disclosure applies to all configurations of the subject technology. A disclosure relating to such phrase(s) may apply to all configurations, or one or more configurations. A disclosure relating to such phrase(s) may provide one or more examples. A phrase such as an aspect or some aspects may refer to one or more aspects and vice versa, and this applies similarly to other foregoing phrases.

[0408] A phrase "at least one of" preceding a series of items, with the terms "and" or "or" to separate any of the items, modifies the list as a whole, rather than each member of the list.　 The phrase "at least one of" does not require selection of at least one item; rather, the phrase allows a meaning that includes at least one of any one of the items, and / or at least one of any combination of the items, and / or at least one of each of the items.　 By way of example, each of the phrases "at least one of A, B, and C" or "at least one of A, B, or C" refers to only A, only B, or only C; any combination of A, B, and C; and / or at least one of each of A, B, and C.

[0409] It is understood that the specific order or hierarchy of steps, operations, or processes disclosed is an illustration of exemplary approaches. Unless explicitly stated otherwise, it is understood that the specific order or hierarchy of steps, operations, or processes may be performed in different order. Some of the steps, operations, or processes may be performed simultaneously or may be performed as a part of one or more other steps, operations, or processes. The accompanying method claims, if any, present elements of the various steps, operations or processes in a sample order, and are not meant to be limited to the specific order or hierarchy presented. These may be performed in serial, linearly, in parallel or in different order. It should be understood that the described instructions, operations, and systems may generally be integrated together in a single software / hardware product or packaged into multiple software / hardware products.

[0410] The disclosure is provided to enable any person skilled in the art to practice the various aspects described herein. In some instances, well-known structures and components are shown in block diagram form to avoid obscuring the concepts of the subject technology. The disclosure provides myriad examples of the subject technology, and the subject technology is not limited to these examples. Various modifications to these aspects will be readily apparent to those skilled in the art, and the principles described herein may be applied to other aspects.

[0411] All structural and functional equivalents to the elements of the various aspects described throughout this disclosure that are known or later come to be known to those of ordinary skill in the art are expressly incorporated herein by reference and are intended to be encompassed by the claims. Moreover, nothing disclosed herein is intended to be dedicated to the public regardless of whether such disclosure is explicitly recited in the claims. No claim element is to be construed under the provisions of 35 U.S.C. §112, sixth paragraph, unless the element is expressly recited using a phrase means for or, in the case of a method claim, the element is recited using the phrase step for.

[0412] The title, background, brief description of the drawings, abstract, and drawings are hereby incorporated into the disclosure and are provided as illustrative examples of the disclosure, not as restrictive descriptions. It is submitted with the understanding that they will not be used to limit the scope or meaning of the claims. In addition, the detailed description provides illustrative examples, and the various features are grouped together in various implementations for the purpose of streamlining the disclosure. This method of disclosure is not to be interpreted as reflecting an intention that the claimed subject matter requires more features than are expressly recited in each claim. Rather, as the following claims reflect, inventive subject matter lies in less than all features of a single disclosed configuration or operation. The following claims are hereby incorporated into the detailed description, with each claim standing on its own as a separately claimed subject matter.

[0413] The claims are not intended to be limited to the aspects described herein, but are to be accorded the full scope consistent with the language claims and to encompass all legal equivalents. Notwithstanding, none of the claims are intended to embrace subject matter that fails to satisfy the requirements of the applicable patent law, nor should they be interpreted in such a way.

Claims

1.A method performed by a user equipment (UE) in a communication system, the method comprising:receiving, from a base station, a radio resource control (RRC) message including information associated with a remaining time threshold of a data;identifying a remaining time of the data; andin case that the identified remaining time of the data is less than the remaining time threshold, transmitting, the a base station, a delay status report (DSR) media access control (MAC) control element (CE) including a buffer status with the remaining time.2.The method of claim 1,wherein the MAC CE includes a logical channel group (LCG) index field and a buffered data size field corresponding to the LCG index field, andwherein the data includes at least one of a packet, a protocol data unit (PDU), a PDU set, or a service data unit (SDU).3.The method of claim 2,in case that the LCG index field is for an extended reality (XR) service, the MAC CE further includes a delay amount field corresponding to the LCG index field.4.The method of claim 1,in case that the identified remaining time of the data is less than the remaining time threshold, triggering the DSR MAC CE transmission.5.A method performed by a base station in a communication system, the method comprising:transmitting, to a user equipment (UE), a radio resource control (RRC) message including information associated with a remaining time threshold of a data; andreceiving, from the UE, a dealy status report (DSR) media access control (MAC) control element (CE) including a buffer status with the remaining time.6.The method of claim 5,wherein the MAC CE includes a logical channel group (LCG) index field and a buffered data size field corresponding to the LCG index field.7.The method of claim 6,in case that the LCG index field is for an extended reality (XR) service, the MAC CE further includes a delay amount field corresponding to the LCG index field.8.The method of claim 5,wherein the data includes at least one of a packet, a protocol data unit (PDU), a PDU set, or a service data unit (SDU).9.A user equipment (UE) in a communication system, the UE comprising:a transceiver; anda controller coupled with the transceiver, and configured to:receive, from a base station, a radio resource control (RRC) message including information associated with a remaining time threshold of a data,identify a remaining time of the data, andin case that the identified remaining time of the data is less than the the remaining time threshold, transmit, to a base station, a delay status report (DSR) media access control (MAC) control element (CE) including a buffer status with the remaining time.10.The UE of claim 9,wherein the MAC CE includes a logical channel group (LCG) index field and a buffered data size field corresponding to the LCG index field, andwherein the data includes at least one of a packet, a protocol data unit (PDU), a PDU set, or a service data unit (SDU).11.The UE of claim 10,in case that the LCG index field is for an extended reality (XR) service, the MAC CE further includes a delay amount field corresponding to the LCG index field.12.The UE of claim 9,in case that the identified remaining time of the data is less than the remaining time threshold, triggering the DSR MAC CE transmission.13.A base station in a communication system, the base station comprising:a transceiver; anda controller coupled with the transceiver, and configured to:transmit, to a user equipment (UE), a radio resource control (RRC) message including information associated with a remaining time threshold of a data, andreceive, from the UE, a delay status report (DSR) media access control (MAC) control element (CE) including a buffer status with the remaining time.14.The base station of claim 13,wherein the MAC CE includes a logical channel group (LCG) index field and a buffered data size field corresponding to the LCG index field, andin case that the LCG index field is for an extended reality (XR) service, the MAC CE further includes a delay amount field corresponding to the LCG index field.15.The base station of claim 13,wherein the data includes at least one of a packet, a protocol data unit (PDU), a PDU set, or a service data unit (SDU).

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