Method and apparatus for handling delay status report for extended reality service in a wireless communication system

Abstract

The disclosure relates to a 5G or 6G communication system for supporting a higher data transmission rate. The present invention discloses a method for handling a Delay Status Report (DSR) for an Extended Reality (XR) service by a user equipment (UE) (100). The method includes in case that a first smallest remaining value of packet data convergence protocol (PDCP) discard timers among all PDCP service data units (SDUs) becomes below a remaining time threshold of a logical channel group (LCG), triggering a delay status report (DSR); and in case that an SDU has not been transmitted in any medium access control (MAC) protocol data unit (PDU) and is associated with the logical channel which triggered the DSR, identifying that the SDU is associated with the DSR.

Description

METHOD AND APPARATUS FOR HANDLING DELAY STATUS REPORT FOR EXTENDED REALITY SERVICE IN A WIRELESS COMMUNICATION SYSTEM

[0001] The present invention relates to wireless communication and, more specifically related, to a method and User Equipment (UE) for handling a Delay Status Report (DSR) for an Extended Reality (XR) service in a wireless network.

[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 (THz) 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 by utilizing ultra-high-performance communication and computing resources.

[0008] The XR is an umbrella term encompassing all real-and-virtual environments generated by computer graphics and devices (or UE). The generated environments include Virtual Reality (VR), Augmented Reality (AR), and Mixed Reality (MR) and are considered essential technologies to enable the realization of digital twin / meta-universe. The XR is incorporated as a work item in fifth generation (5G) Advanced (i.e., Third Generation Partnership Project (3GPP) Release 18), which is targeted to provide a communication system framework that fulfills the challenging needs of high data rate with very low latency and power-efficient connectivity for XR applications.

[0009] Protocol Data Convergence Protocol (PDCP), Radio Link Control (RLC), and Medium Access Control (MAC) are layer-2 sub-layers and are involved in a number of functionalities for the data plane processing of the transmitted and received packets. In the legacy Buffer Status Report (BSR), a reporting procedure involves sending a buffered data status (e.g., size of the buffered data) across different Logical Channel Groups (LCGs). This facilitates the scheduling operation of a network (or network entity), i.e., the network entity can allocate the uplink grants to the 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 the BSR. In general, the buffered data may have different delay statuses as the data storage at the buffer may have happened at different points in time. Moreover, the different services have different packet delay budgets, which implies the buffered data (i.e., a packet or a Service Data Unit (SDU)) can be discarded when it overshoots the packet delay budget limit or any associated limit configured. A SDU discard procedure involves discarding a PDCP SDU when an associated timer has expired or a successful delivery of the PDCP SDU is confirmed from a peer PDCP entity, e.g., through a PDCP status report.

[0010] For the XR applications, the existing buffer status reporting may not be efficient and effective as the XR applications may be extremely delay sensitive and require low latency of performance. As a result, a Delay Status Report (DSR) mechanism has been introduced which incorporates both the delay information and the pertinent buffered data information to be conveyed to the network entity to enable better scheduling from the network entity for the XR applications. However, the DSR mechanism in a conventional system (i.e., 3GPP TS 38.321 v18.0.0) may lead to undesired results or in-efficiencies in operation. For example, DSR may not be cancelled as expected or DSR is not triggered as expected.

[0011] Thus, it is desired to address the above mentioned disadvantages or other shortcomings or at least provide a useful alternative.

[0012] The principal object of the invention herein is to provide a methods and systems (or wireless network) for providing an enhanced DSR cancellation mechanism for an XR service in a wireless network.

[0013] Another object of the invention herein is to determine a SDU association with a DSR.

[0014] Another object of the invention herein is to ensure completeness of DSR MAC CE.

[0015] Another object of the invention herein is to prioritize DSR MAC CE transmission.

[0016] Another object of the invention herein is to disclose about DSR MAC CE update during transmission or retransmission.

[0017] Another object of the invention herein is to disclose about DSR cancellation based on DSR configuration or reconfiguration (modification, release).

[0018] Another object of the invention herein is to disclose about SR cancellation and RA cancellation based on DSR configuration or reconfiguration.

[0019] Embodiments disclosed herein provide a method for handling a Delay Status Report (DSR) for an XR service. The method includes determining, by a user equipment (UE), that at least one Packet Data Convergence Protocol (PDCP) service data unit (SDU) has not been transmitted in a Medium Access Control (MAC) Protocol Data Unit (PDU), the at least one PDCP SDU is associated with a Logical Channel of a Logical Channel Group (LCG) that triggers at least one DSR, and the at least one PDCP SDU is a delay-critical PDCP SDU wherein a remaining value of PDCP discard Timer associated with the at least one PDCP SDU is below a remaining time threshold value. The method includes associating, by the UE, the at least one PDCP SDU with the at least one DSR based on the determination.

[0020] Embodiments disclosed herein provide a UE including a DSR controller coupled with a processor and a memory. The DSR controller is configured to determine that at least one PDCP SDU has not been transmitted in a MAC PDU, the at least one PDCP SDU is associated with a Logical Channel of a LCG that triggers at least one DSR, and the at least one PDCP SDU is a delay-critical PDCP SDU wherein a remaining value of PDCP discard Timer associated with the at least one PDCP SDU is below a remaining time threshold value. Further, the DSR controller is configured to associate the at least one PDCP SDU with at least one DSR based on the determination.

[0021] In an embodiment, the method includes determining, by the UE, the MAC PDU cannot accommodate the at least one SDU associated with at least one pending DSR. Further, the method includes performing, by the UE, that a MAC entity of the UE includes a DSR MAC CE in the MAC PDU based on the determination.

[0022] In an embodiment, the DSR MAC CE is a complete DSR MAC CE. The complete DSR MAC CE comprises delay information for all the SDUs associated with all the pending DSRs.

[0023] In an embodiment, the delay information comprises at least one of: remaining time and buffer size.

[0024] In an embodiment, the DSR MAC CE is prioritized over the at least one SDU associated with the at least one pending DSR for inclusion in the MAC PDU, when the MAC PDU cannot accommodate together the DSR MAC CE and the at least one SDU associated with the at least one pending DSR.

[0025] In an embodiment, the method includes determining, by the UE, uplink resources accommodating all SDUs associated with the at least one DSR for transmission. Further, the method includes cancelling, by the UE, the at least one pending DSR based on the determination, wherein the at least one pending DSR is at least one triggered DSR.

[0026] In an embodiment, the at least one pending DSR is cancelled, when the MAC PDU is transmitted and the MAC PDU includes the DSR MAC CE, wherein delay information for all SDUs associated with the at least one pending DSR is reported in the DSR MAC CE, wherein the at least one pending DSR is at least one triggered DSR.

[0027] In an embodiment, the method includes determining, by the UE, that an uplink grant accommodates all the SDUs associated with the corresponding pending DSR in a MAC PDU and the MAC PDU is transmitted. Further, the method includes cancelling, by the UE, the pending DSR based on the determination.

[0028] In an embodiment, the method includes determining, by the UE, that all the SDUs associated with the corresponding pending DSR are discarded. Further, the method includes cancelling, by the UE, the pending DSR based on the determination.

[0029] In an embodiment, the method includes triggering, by the UE, at least one of: the at least one DSR and a Scheduling Request (SR) for the at least one DSR after an assembly of a MAC PDU that contains a DSR MAC CE but before a transmission of the MAC PDU.

[0030] In an embodiment, the method includes triggering, by the UE, at least one of: the at least one DSR and a SR for the at least one DSR during a MAC PDU assembly.

[0031] In an embodiment, a remaining time field for a delay information carried in a DSR MAC CE comprises remaining time, wherein the remaining time is a smallest remaining value of a PDCP discard timer among all PDCP SDUs buffered for the LCG that has not been transmitted in the MAC PDU, wherein the remaining time is determined at the time of a first symbol of a first Physical Uplink Shared Channel (PUSCH) transmission that comprises the DSR MAC CE.

[0032] In an embodiment, the method includes determining, by the UE, at least one of: a configuration associated with a DSR functionality and a reconfiguration associated with the DSR functionality for the LCG at least one of: disables a DSR function for the LCG and releases a DSR function for the LCG. The method includes cancelling, by the UE, a pending DSR for the LCG based on the determination.

[0033] In an embodiment, the pending DSR for a logical channel of the LCG is cancelled when at least one parameter related to at least one of a DSR triggering and a DSR transmission in at least one of the configuration associated with the DSR functionality and the reconfiguration associated with the DSR functionality for the LCG is changed.

[0034] In an embodiment, the method includes determining, by the UE, at least one condition is met. The method includes stopping, by the UE, an ongoing random access procedure that was initiated due to a pending SR for the DSR based on the determination, wherein the pending SR has no valid physical uplink control channel (PUCCH) resources configured.

[0035] In an embodiment, the at least one condition comprises the DSR that triggered the SR has been cancelled due to at least one of: (a) a configuration associated with the DSR functionality and a reconfiguration of the DSR functionality for the LCG that disables the DSR function or releases the DSR configuration for the LCG, (b) the at least one DSR that triggered the SR has been cancelled due to at least one of: a configuration associated with the DSR functionality and a reconfiguration associated with the DSR functionality for the LCG that changes a DSR parameter that affects DSR triggering or DSR transmission, (c) the DSR that triggered the SR has been cancelled when all the SDUs associated with the DSR have been discarded, and (d) the MAC PDU is transmitted using an uplink (UL) grant other than a UL grant provided by Random Access Response (RAR) or a UL grant for the transmission of an MSGA payload, wherein the MAC PDU includes at least one of: all the SDUs associated with the DSR or the DSR MAC CE that includes delay information of all the SDUs associated with the DSR.

[0036] In an embodiment, the method includes cancelling, by the UE, a SR when the at least one DSR that triggered the SR has been cancelled due to at least one of: a configuration associated with the DSR functionality and a reconfiguration associated with the DSR functionality for the LCG that performs at least one of: disables the DSR function, releases the DSR configuration for the LCG and changes at least one DSR parameter that affects at least one of: DSR triggering and DSR transmission.

[0037] In an embodiment, the method includes excluding, by the UE, delay information in a DSR MAC CE in at least one of transmission associated with the MAC PDU and retransmission associated with the MAC PDU that pertains to the delay information for the at least one DSR that is cancelled.

[0038] In an embodiment, the method includes updating, by the UE, delay information for the at least one DSR included in the DSR MAC CE when the MAC PDU is retransmitted. The update is based on at least one of: a time elapsed between a first transmission and a retransmission, an applicability of the delay information for the at least one DSR, and a cancellation status for the at least one DSR.

[0039] These and other aspects of the 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 preferred 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 embodiments herein, and the embodiments herein include all such modifications.

[0040] Aspects of the present disclosure provide efficient communication methods in a wireless communication system.

[0041] These and other features, aspects, and advantages of the present invention 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 drawings, in which:

[0042] FIGURE 1 illustrates a wireless network for handling a DSR for an XR service, according to embodiments as disclosed herein;

[0043] FIGURE 2 illustrates various hardware components of a UE, according to embodiments as disclosed herein;

[0044] FIGURE 3 illustrates a flow chart illustrating a method for handling the DSR for the XR service, according to embodiments as disclosed herein;

[0045] FIGURE 4 illustrates an example flowchart that illustrates a DSR cancellation mechanism at a MAC entity for the XR service in the wireless network, according to embodiments as disclosed herein; and

[0046] FIGURE 5 illustrates an example flowchart that illustrates a DSR triggering mechanism at the MAC entity for XR service in the wireless network, according to embodiments as disclosed herein;

[0047] FIGURE 6 illustrates a block diagram illustrating a structure of a UE according to embodiments as disclosed herein; and

[0048] FIGURE 7 illustrates a block diagram illustrating a structure of a base station according to embodiments as disclosed herein.

[0049] 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.

[0050] 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.

[0051] 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.

[0052] 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.

[0053] 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.

[0054] Embodiments disclosed herein provide a method and UE for handling a DSR for an XR service in a wireless network. The method includes determining, by the UE, that at least one PDCP SDU has not been transmitted in a MAC PDU, the at least one PDCP SDU is associated with a Logical Channel of a LCG that triggers at least one DSR, and the at least one PDCP SDU is a delay-critical PDCP SDU wherein a remaining value of PDCP discard Timer associated with the at least one PDCP SDU is below a remaining time threshold value. The method includes associating, by the UE, the at least one PDCP SDU with the at least one DSR based on the determination.

[0055] Embodiments disclosed herein provide methods and UE for providing a DSR cancellation mechanism for the XR service in a wireless network. A MAC entity of the UE cancels a pending DSR for a logical channel of the specific LCG when the configuration and / or reconfiguration of DSR functionality for the LCG disables the DSR function for the LCG or releases the DSR configuration for the LCG. Further, the MAC entity of the UE cancels a pending DSR for the logical channel of the specific LCG when at least one parameter related to the DSR triggering and / or DSR transmission in the configuration and / or reconfiguration of DSR functionality for the LCG is at least one of changed, added, or removed. Further, the MAC entity of the UE triggers a new DSR for the logical channel of the specific LCG when the configuration and / or reconfiguration of DSR functionality for the LCG is received that enables the DSR function for the LCG or sets up the DSR configuration for the LCG. Further, the MAC entity of the UE triggers a new DSR for the logical channel of the specific LCG in accordance with the new parameters when at least one parameter related to the DSR triggering and / or DSR transmission in the configuration and / or reconfiguration of DSR functionality for the LCG is at least one of changed, added, or removed.

[0056] Unlike the existing mechanisms, embodiments herein provide an enhanced DSR cancellation mechanism for extended reality in wireless networks. The UE and the network entity performance is improved for the XR application. The proposed method ensures providing the appropriate and accurate DSR reporting to the network entity that enables the effective and proper scheduling from the network entity for the UE.

[0057] Referring now to the drawings, and more particularly to FIGS. 1-5, where similar reference characters denote corresponding features consistently throughout the figures, there are shown embodiments.

[0058] FIGURE 1 illustrates a wireless network (1000) for handling a DSR for an XR service, according to embodiments as disclosed herein. The wireless network (1000) can be, for example, but not limited to a fourth generation (4G) network, a fifth generation (5G) network, a sixth generation (6G) network, and an Open Radio Access Network (ORAN).

[0059] The wireless network (1000) includes a UE (100) and a network entity (200). The UE (100) can be, for example, but not limited to a laptop, a smart phone, a desktop computer, a notebook, a Device-to-Device (D2D) device, a vehicle to everything (V2X) device, a foldable phone, a smart TV, a tablet, an immersive device, and an internet of things (IoT) device. The network entity (200) can be, for example, but not limited to an gNB, an eNB, a base station, a TRP unit, and a new radio (NR) trans-receiver.

[0060] In an embodiment, the UE (100) receives a configuration or reconfiguration of a DSR functionality for a LCG in a RRC signaling from the network entity (200). Further, the UE (100) determines whether the configuration or reconfiguration of the DSR functionality for the LCG is at least one of disable the DSR function for the LCG and release the DSR configuration for the LCG.

[0061] In an embodiment, the UE (100) determines that the configuration or reconfiguration of the DSR functionality for the LCG is at least one of disable the DSR function for the LCG and release the DSR configuration for the LCG, the MAC entity of the UE (100) cancels the pending DSR for at least one logical channel of the LCG. In another embodiment, the UE (100) does not determine that the configuration or reconfiguration of the DSR functionality for the LCG is at least one of disable the DSR function for the LCG and release the DSR configuration for the LCG, then, the MAC entity of the UE (100) skips to cancel the pending DSR for the at least one logical channel of the LCG.

[0062] The UE (100) receives the configuration or reconfiguration of the DSR functionality for the LCG in the RRC signaling from the network entity (200). Further, the UE (100) determines that the configuration or reconfiguration of the DSR functionality for the LCG is at least one of the enabling the DSR function for the LCG and setting up the DSR configuration for the LCG. Based on the determination, the MAC entity of the UE (100) triggers DSR for the at least one logical channel of the LCG.

[0063] In an embodiment, the UE (100) determines at least one PDCP SDU has not been transmitted in a MAC PDU, the at least one PDCP SDU is associated with a Logical Channel of a LCG that triggers at least one DSR, and the at least one PDCP SDU is a delay-critical PDCP SDU wherein a remaining value of PDCP discard Timer associated with the at least one PDCP SDU is below a remaining time threshold value. Based on the determination, the UE (100) is configured to associate the at least one PDCP SDU with at least one DSR.

[0064] In an embodiment, one or more permutations or combinations of the embodiments described further in the proposed solution can be utilized for the DSR handling mechanism.

[0065] In an embodiment, when a LCG is configured for delay status reporting, the MAC entity of the UE (100) triggers the DSR for the logical channel of the LCG if:

[0066] a) the smallest remaining value of the PDCP discard timers among all the data (e.g., all the PDCP SDUs) buffered for the logical channel of the LCG that has not been transmitted in any MAC PDU, or

[0067] b) reported as data volume in a DSR MAC CE becomes below the remaining time threshold of the LCG, and

[0068] c) if there is no DSR pending for the logical channel of the LCG.

[0069] In an embodiment, an example of a 3GPP specification is provided that depicts the DSR mechanism as follows:

[0070] Example 1:

[0071] If an LCG is configured for delay status reporting, the MAC entity shall:

[0072] 1> if the smallest remaining value of the PDCP discard timers among all the data buffered for the logical channel of the LCG that has not been transmitted in any MAC PDU or reported as data volume in a DSR MAC CE becomes below the remaining time threshold of the LCG, and

[0073] 1> if there is no DSR pending for the logical channel of the LCG,

[0074] 2> trigger a DSR for the logical channel of the LCG.

[0075] In an embodiment, the DSR for the logical channel of the LCG is triggered when the smallest remaining time of discard timers among all SDUs buffered in the logical channel of the LCG, which has not been transmitted or considered as part of data volume in previous DSR MAC CEs, becomes below the configured threshold value for that LCG and there is no pending DSR triggered for that logical channel of the LCG since the last assembly of the DSR MAC CE.

[0076] In an embodiment example, specification text is given below:

[0077] If the LCG is configured for delay status reporting, the MAC entity shall:

[0078] 1> if the smallest remaining value of the PDCP discard timers among all the data buffered for the logical channel of the LCG that has not been transmitted in any MAC PDU or reported as data volume in a DSR MAC CE becomes below the remaining time threshold of the LCG and

[0079] 1> if there is no DSR pending for the logical channel of the LCG since the last DSR MAC CE was assembled,

[0080] 2> trigger a DSR for the logical channel of the LCG.

[0081] In an embodiment, a pending DSR for the at least one logical channel of the specific LCG is canceled when the configuration and / or reconfiguration of DSR functionality for the LCG disables the DSR function for the LCG.

[0082] In an embodiment, a pending DSR for the at least one logical channel of the specific LCG is cancelled when the configuration and / or reconfiguration of DSR functionality for the LCG releases the DSR configuration for the LCG.

[0083] In an embodiment, the DSR for the at least one logical channel of the specific LCG is triggered when the configuration and / or reconfiguration of DSR functionality is received for the LCG that enables the DSR function for the LCG.

[0084] In an embodiment, the DSR for the at least one logical channel of the specific LCG is triggered when the configuration and / or reconfiguration of DSR functionality is received for the LCG that sets up the DSR configuration for the LCG.

[0085] In an embodiment, the configuration and / or reconfiguration of DSR functionality for the LCG may be received in an RRC signaling message (e.g., in the MAC-CellGroupConfig as part of the RRCReconfiguration message).

[0086] In an embodiment, a pending DSR for the at least one logical channel of the specific LCG is cancelled when at least one parameter related to the DSR triggering and / or DSR transmission in the configuration and / or reconfiguration of DSR functionality for the LCG is at least one of changed / modified (e.g., a change for the corresponding value range, applicability, identity, index, activation, deactivation, enable, disable status) or added or removed. The parameter related to the DSR triggering and / or DSR transmission in the configuration and / or reconfiguration of DSR functionality for the LCG may include at least one of the following:

[0087] a) Logical Channel Group (LCG) identity (also termed as, LCG-Id);

[0088] b) Remaining Time threshold (also termed as, remainingTimeThreshold);

[0089] c) logicalChannelSR-DelayTimerApplied (or DSR-logicalChannelSR-DelayTimerApplied);

[0090] d) LogicalChannelSR-DelayTimer (or DSR- LogicalChannelSR-DelayTimer);

[0091] e) logicalChannelSR-Mask (or DSR- logicalChannelSR-Mask);

[0092] f) Logical Channel Prioritization (LCP) restrictions configuration; and

[0093] g) Scheduling Request (SR) configuration parameters for the logical channel (or logical channel group) including periodicity, offset, type, priority, association to critical / emergency / low latency service.

[0094] In an embodiment, a new DSR for the at least one logical channel of the specific LCG is triggered in accordance with the modified parameters when at least one parameter related to the DSR triggering and / or DSR transmission in the configuration and / or reconfiguration of DSR functionality for the LCG is at least one of changed / modified (e.g., a change for the corresponding value, range, applicability, identity, index, activation, deactivation, enable, disable, status), or added, or removed. The parameter related to the DSR triggering and / or DSR transmission in the configuration and / or reconfiguration of DSR functionality for the LCG may include at least one of the following:

[0095] a) Logical Channel Group (LCG) identity (also termed as, LCG-Id);

[0096] b) Remaining Time threshold (also termed as, remainingTimeThreshold);

[0097] c) logicalChannelSR-DelayTimerApplied (or DSR-logicalChannelSR-DelayTimerApplied);

[0098] d) LogicalChannelSR-DelayTimer (or DSR- LogicalChannelSR-DelayTimer);

[0099] e) logicalChannelSR-Mask (or DSR- logicalChannelSR-Mask);

[0100] f) Logical Channel Prioritization (LCP) restrictions configuration; and

[0101] g) Scheduling Request (SR) configuration parameters for the logical channel (or logical channel group) including periodicity, offset, type, priority, association to critical / emergency / low latency service.

[0102] In an embodiment, the DSR configuration includes the timer configuration for LogicalChannelSR-DelayTimer (or DSR-LogicalChannelSR-DelayTimer), which is applied to the relevant logical channel of the LCG if the logical channel is configured with a parameter logicalChannelSR-DelayTimerApplied (or DSR-logicalChannelSR-DelayTimerApplied) set as TRUE. This indicates to apply the delay timer (LogicalChannelSR-DelayTimer or DSR-LogicalChannelSR-DelayTimer) for SR transmission for this logical channel (e.g., SR for the DSR). LogicalChannelSR-DelayTimer or DSR-LogicalChannelSR-DelayTimer may be configured along with the DSR configuration for a specific LCG or collectively for all the configured LCGs. Further, the relevant logical channel of the LCG may be configured with a parameter logicalChannelSR-Mask (or DSR-logicalChannelSR-Mask). This indicates to mask or block the SR transmission for this logical channel (e.g., SR for the DSR).

[0103] In an embodiment, a pending DSR is cancelled when the LogicalChannelSR-DelayTimer (or DSR-LogicalChannelSR-DelayTimer) is at least one of setup, removed, or modified that is applicable for the SR configuration of the relevant logical channel of the LCG.

[0104] In an embodiment, the pending DSR is cancelled when the LogicalChannelSR-DelayTimerApplied (or DSR-LogicalChannelSR-DelayTimerApplied) is at least one of setup (e.g., set as TRUE), removed (e.g., set as FALSE), or modified that is applicable for the SR configuration of the relevant logical channel of the LCG.

[0105] In an embodiment, the pending DSR is cancelled when the logicalChannelSR-Mask (or DSR-logicalChannelSR-Mask) is at least one of setup (e.g., set as TRUE), removed (e.g., set as FALSE), or modified that is applicable for the SR configuration of the relevant logical channel of the LCG.

[0106] In an embodiment, a pending SR for the DSR is cancelled when the LogicalChannelSR-DelayTimer (or DSR-LogicalChannelSR-DelayTimer) is at least one of setup, removed, or modified that is applicable for the SR configuration of the relevant logical channel of the LCG.

[0107] In an embodiment, the pending SR for the DSR is cancelled when the LogicalChannelSR-DelayTimerApplied (or DSR-LogicalChannelSR-DelayTimerApplied) is at least one of setup (e.g., set as TRUE), removed (e.g., set as FALSE), or modified that is applicable for the SR configuration of the relevant logical channel of the LCG.

[0108] In an embodiment, a pending SR for DSR is cancelled when the logicalChannelSR-Mask (or DSR-logicalChannelSR-Mask) is at least one of setup (e.g., set as TRUE), removed (e.g., set as FALSE), or modified that is applicable for the SR configuration of the relevant logical channel of the LCG.

[0109] In an embodiment, the pending SR for the DSR is cancelled when the logical channel restriction is configured or applied for the relevant logical channel of the LCG.

[0110] In an embodiment, an example of 3GPP specification is provided that depicts the DSR configuration and / or reconfiguration as follows:

[0111] Example 2:

[0112] MAC-CellGroupConfig:The IE MAC-CellGroupConfig is used to configure MAC parameters for a cell group, including DRX.

[0113]

[0114] DSR-logicalChannelSR-DelayTimer:

[0115] Value in number of subframes. Value sf20 corresponds to 20 subframes, sf40 corresponds to 40 subframes, and so on.

[0116] In an embodiment, the SDU is considered to be associated with a DSR if it is associated with the LCG which triggered the DSR and the remaining value of its PDCP discardTimer is below remainingTimeThreshold.

[0117] In an embodiment, the SDU is considered to be associated with a DSR if it has not been transmitted in any MAC PDU and it is associated with the LCG which triggered the DSR and the remaining value of its PDCP discardTimer is below remainingTimeThreshold.

[0118] In an embodiment, the SDU is considered to be associated with a DSR if it has not been transmitted in any MAC PDU or reported as data volume in a DSR MAC CE and it is associated with the logical channel of the LCG which triggered the DSR and the remaining value of its PDCP discardTimer is below remainingTimeThreshold.

[0119] In an embodiment, the MAC entity cancels a pending DSR when all the not-yet-transmitted SDUs associated with the DSR have been discarded.

[0120] In an embodiment, the MAC entity cancels the pending DSR when the MAC PDU has been transmitted and this MAC PDU includes all the not-yet-transmitted SDUs associated with the DSR.

[0121] In an embodiment, the MAC entity cancels the pending DSR when a MAC PDU has been transmitted and this MAC PDU includes a DSR MAC CE that contains the delay information of all the not-yet-transmitted SDUs associated with the DSR.

[0122] In an embodiment, the MAC entity may include a partial DSR MAC CE in a MAC PDU if the MAC PDU cannot accommodate the SDUs associated with all the pending DSRs. Further, the partial DSR MAC CE may include the delay information (remaining time and buffer size) for all the SDUs associated with those pending DSRs for which all the associated SDUs could not be accommodated in the MAC PDU.

[0123] In an embodiment, the MAC entity may include a complete DSR MAC CE in a MAC PDU, if the MAC PDU cannot accommodate the SDUs associated with all the pending DSRs. Further, the complete DSR MAC CE may include the delay information (e.g., remaining time and buffer size) for all the SDUs associated with all the pending DSRs, irrespective of whether all the associated SDUs of the DSRs could be accommodated or could not be accommodated in the MAC PDU.

[0124] In an embodiment, the DSR MAC CE is prioritized over the SDUs associated with the pending DSRs for inclusion in the MAC PDU, when the MAC PDU cannot accommodate together the DSR MAC CE and the SDUs associated with all the pending DSRs.

[0125] In an embodiment, when the uplink resources available are not sufficient to accommodate the complete DSR MAC CE (i.e., all the pending DSRs), the MAC entity may accommodate pending DSRs over two or more partial MAC CEs. These partial MAC CEs may be transmitted over multiple uplink resources or grants (e.g. dynamic grants and / or configured uplink grants).

[0126] In an embodiment, all triggered (or pending) DSRs may be cancelled, when the uplink resources can accommodate all the SDUs associated with all the DSRs for transmission.

[0127] In an embodiment, a triggered (or pending) DSR may be cancelled, when the uplink resources can accommodate all the SDUs associated with the DSR for transmission.

[0128] In an embodiment, all DSRs triggered prior to MAC PDU assembly are cancelled, when a MAC PDU is transmitted and this PDU includes a complete DSR MAC CE; i.e., delay information (Remaining time and Buffer size) for all the SDUs associated with all the triggered (or pending) DSRs are reported in the DSR MAC CE.

[0129] In an embodiment, a DSR triggered prior to MAC PDU assembly is cancelled, when a MAC PDU is transmitted and this PDU includes a DSR MAC CE wherein, delay information (Remaining time and Buffer size) for all the SDUs associated with the triggered (or pending) DSR is reported in the DSR MAC CE.

[0130] In an embodiment, a pending DSR may be cancelled, when the uplink grant(s) can accommodate all the SDUs associated with the corresponding DSR in a MAC PDU and the MAC PDU is transmitted.

[0131] In an embodiment, all pending DSRs may be cancelled, when the uplink grant(s) can accommodate all the SDUs associated with the corresponding DSRs in a MAC PDU and the MAC PDU is transmitted.

[0132] In an embodiment, a triggered DSR may be cancelled, when the uplink grant(s) can accommodate DSR MAC CE plus its sub-header as a result of logical channel prioritization and the DSR MAC CE includes the delay information (Remaining Time and Buffer Size) for at least the pertinent DSR for the LCG; i.e., the DSR MAC CE may be a complete DSR MAC CE or a partial DSR MAC CE.

[0133] In an embodiment, only those triggered DSRs may be cancelled, when the uplink grant(s) can accommodate DSR MAC CE plus its sub-header as a result of logical channel prioritization and the DSR MAC CE includes the delay information (Remaining Time and Buffer Size) for the pertinent DSRs for the LCGs. That is, the DSR MAC CE may be a partial DSR MAC CE.

[0134] In an embodiment, all triggered DSRs may be cancelled, when the uplink grant(s) can accommodate DSR MAC CE plus its sub-header as a result of logical channel prioritization and the DSR MAC CE includes the delay information (Remaining Time and Buffer Size) for all the triggered DSRs for the LCGs. That is, the DSR MAC CE may be a complete DSR MAC CE.

[0135] In an embodiment, all DSRs triggered prior to MAC PDU assembly shall be cancelled, when a MAC PDU is transmitted and this PDU includes a DSR MAC CE which contains the delay information of all the SDUs associated up to (and including) the last event that triggered a DSR prior to the MAC PDU assembly.

[0136] In an embodiment, a DSR and / or a SR for DSR may be triggered after the assembly of a MAC PDU that contains a DSR MAC CE but before the transmission of this MAC PDU.

[0137] In an embodiment, DSR and / or a SR for DSR may be triggered during the MAC PDU assembly.

[0138] In an embodiment, the MAC entity of the UE (100) determines the availability of the uplink grant, which may be for the transmission of the DSR MAC CE and / or for the transmission of the SDUs associated with the DSR. This availability comprises at least one of the present availability of the uplink grant and the future availability of the uplink grant. The future availability of the uplink grant may be based on the occasion of the actual uplink transmission for the received dynamic grants or the occasion of the transmission for the configured grant.

[0139] In another embodiment, the UE (100) may consider at least one future grant, whose transmission is within or up to a determined future time threshold, to be available. The future time threshold can be specified to be a certain value (e.g., 4 ms) or determined by the UE implementation.

[0140] In an embodiment, the Remaining Time field for the delay information carried in the DSR MAC CE comprises a remaining time. This remaining time is the smallest remaining value of the PDCP discardTimer(s) among all PDCP SDUs buffered for the LCG that has not been transmitted in any MAC PDU. The remaining time is determined at the time of the first symbol of the first Physical Uplink Shared Channel (PUSCH) transmission that includes this DSR MAC CE.

[0141] In an embodiment, the Remaining Time field for the delay information carried in the DSR MAC CE comprises a remaining time. This remaining time is the smallest remaining value of the PDCP discardTimer(s) among all PDCP SDUs buffered for the LCG that has not been transmitted in any MAC PDU or reported as data volume in a DSR MAC CE. The remaining time is determined at the time of the first symbol of the first PUSCH transmission that includes this DSR MAC CE.

[0142] In an embodiment, the Remaining Time field for the delay information carried in the DSR MAC CE comprises a remaining time, which is the smallest remaining value of the PDCP discardTimer(s) among the data buffered for the LCG that has not been transmitted in any MAC PDU. This remaining time is determined at the time of the first symbol of the first PUSCH transmission that includes this DSR MAC CE.

[0143] In an embodiment, the Remaining Time field for the delay information carried in the DSR MAC CE comprises a remaining time, which is the smallest remaining value of the PDCP discardTimer(s) among the data buffered for the LCG that has not been transmitted in any MAC PDU or reported as data volume in a DSR MAC CE. This remaining time is determined at the time of the first symbol of the first PUSCH transmission that includes this DSR MAC CE.

[0144] In an embodiment, 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 and if the delay information for all the pending DSRs are included in the DSR MAC CE, the MAC entity may not trigger a SR for this DSR.

[0145] In an embodiment, if the 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 and if the delay information for at least one pending DSRs is not included in the DSR MAC CE, the MAC entity may trigger a SR for at least one pending DSR for which the delay information is not included in the DSR MAC CE.

[0146] In an embodiment, if the 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) and if the DSR MAC CE is not yet transmitted, the MAC entity may trigger a SR for at least one pending DSR for which the delay information is included in the DSR MAC CE, but MAC PDU is not yet transmitted.

[0147] In an embodiment, 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 and if the DSR MAC CE is not yet transmitted, the MAC entity may skip triggering a SR for at least one pending DSR for which the delay information is included in the DSR MAC CE.

[0148] In an embodiment, if a HARQ process is configured with cg-RetransmissionTimer and if the DSR is already included in a MAC PDU for transmission on configured grant by this HARQ process, but not yet transmitted by lower layers, it is up to UE implementation how to handle the DSR content. In an embodiment herein, the UE (100) may update the delay information included for the DSR, as per the actual transmision time. In another embodiment herein, the UE (100) may not update the delay information included for the DSR, as per actual transmission time.

[0149] In an embodiment, the MAC entity of the UE (100) may stop an ongoing Random Access procedure due to a pending SR for DSR, which has no valid PUCCH resources configured, if at least one of the conditions are met:

[0150] a) A MAC PDU is transmitted using an uplink (UL) grant other than a UL grant provided by Random Access Response (RAR) or a UL grant determined as specified in clause 5.1.2a (technical specification (TS) 38.321) for the transmission of the MSGA payload, and this PDU includes either all the SDUs associated with the DSR or a DSR MAC CE that contains the delay information of all the SDUs associated with the DSR.

[0151] b) The DSR that triggered the SR has been cancelled when all the SDUs associated with the DSR have been discarded.

[0152] c) The DSR that triggered the SR has been cancelled due to configuration or reconfiguration of the DSR functionality for LCG that disables the DSR function or releases the DSR configuration for LCG.

[0153] d) The DSR that triggered the SR has been cancelled due to configuration or reconfiguration of the DSR functionality for LCG that changes the DSR parameters which affects DSR triggering or DSR transmission.

[0154] In an embodiment, an example of the specification is provided for handling the Random Access procedure due to a pending SR for DSR, which has no valid PUCCH resources configured, as follows:

[0155] Example 3:

[0156] The MAC entity may stop, if any, an ongoing Random Access procedure due to a pending SR for the DSR, which has no valid PUCCH resources configured, if:

[0157] a) The MAC PDU is transmitted using the UL grant other than a UL grant provided by Random Access Response or a UL grant determined as specified in clause 5.1.2a (TS 38.321) for the transmission of the MSGA payload, and this PDU includes either all the SDUs associated with the DSR or a DSR MAC CE that contains the delay information of all the SDUs associated with the DSR; or

[0158] b) the DSR that triggered the SR has been cancelled when all the SDUs associated with the DSR have been discarded; or

[0159] c) the DSR that triggered the SR has been cancelled due to configuration or reconfiguration of the DSR functionality for LCG that disables the DSR function or releases the DSR configuration for the LCG; or

[0160] d) the DSR that triggered the SR has been cancelled due to configuration or reconfiguration of the DSR functionality for LCG that changes the DSR parameters which affects DSR triggering or DSR transmission.

[0161] In an embodiment, the MAC entity of the UE (100) may stop the ongoing Random Access procedure due to the pending SR for DSR, which has no valid PUCCH resources configured, if at least one of the conditions are met:

[0162] a) A MAC PDU is transmitted using a UL grant other than a UL grant provided by Random Access Response or a UL grant determined as specified in clause 5.1.2a (TS 38.321) for the transmission of the MSGA payload, and this PDU includes a DSR MAC CE that contains the delay information of all the delay-critical SDUs up to (and including) the last event that triggered a DSR prior to the MAC PDU assembly.

[0163] b) The UL grant(s) can accommodate all pending data for transmission associated to the DSR.

[0164] c) The DSR that triggered the SR has been cancelled when all the SDUs associated with the DSR have been discarded.

[0165] d) The DSR that triggered the SR has been cancelled due to configuration or reconfiguration of the DSR functionality for LCG that disables the DSR function or releases the DSR configuration for LCG.

[0166] e) The DSR that triggered the SR has been cancelled due to configuration or reconfiguration of the DSR functionality for LCG that changes the DSR parameters which affects DSR triggering or DSR transmission.

[0167] In an embodiment, an example of the specification is provided for handling the Random Access procedure due to a pending SR for DSR, which has no valid PUCCH resources configured.

[0168] Example 4:

[0169] The MAC entity may stop, if any, the ongoing Random Access procedure due to a pending SR for DSR, which has no valid PUCCH resources configured, if:

[0170] a) The MAC PDU is transmitted using a UL grant other than a UL grant provided by Random Access Response or a UL grant determined as specified in clause 5.1.2a (TS 38.321) for the transmission of the MSGA payload, and this PDU includes a DSR MAC CE that contains the delay information of all the delay-critical SDUs up to (and including) the last event that triggered a DSR prior to the MAC PDU assembly; or

[0171] b) The UL grant(s) can accommodate all pending data for transmission associated to the DSR; or

[0172] c) The DSR that triggered the SR has been cancelled when all the SDUs associated with the DSR have been discarded; or

[0173] d) The DSR that triggered the SR has been cancelled due to configuration or reconfiguration of the DSR functionality for LCG that disables the DSR function or releases the DSR configuration for LCG; or

[0174] e) The DSR that triggered the SR has been cancelled due to configuration or reconfiguration of the DSR functionality for LCG that changes the DSR parameters which affects DSR triggering or DSR transmission.

[0175] In an embodiment, the MAC entity cancels the SR when the DSR that triggered the SR has been cancelled due to configuration or reconfiguration of the DSR functionality for LCG that disables the DSR function.

[0176] In an embodiment, the MAC entity cancels the SR, when the DSR that triggered the SR has been cancelled due to configuration or reconfiguration of the DSR functionality for LCG that releases the DSR configuration for the LCG.

[0177] In an embodiment, the MAC entity cancels the SR, when the DSR that triggered the SR has been cancelled due to configuration or reconfiguration of the DSR functionality for LCG that changes at least one DSR parameter which affects DSR triggering and / or DSR transmission.

[0178] In an embodiment, the MAC entity excludes the delay information in the DSR MAC CE in the transmission or retransmission of the MAC PDU that pertains to the delay information for a DSR that is cancelled.

[0179] In an embodiment, the MAC entity excludes the DSR MAC CE in the transmission or retransmission of the MAC PDU that pertains to the delay information for a DSR that is cancelled.

[0180] In an embodiment, the MAC entity updates the delay information for the DSRs included in the DSR MAC CE when the MAC PDU is retransmitted. The update is based on the time elapsed between the first transmission and the retransmission and / or applicability of the delay information for the included DSRs and / or cancellation status for the included DSRs.

[0181] In an embodiment, the MAC entity of the UE (100) determines whether the DSR is triggered for the logical channel of the LCG for which DSR-logicalChannelSR-DelayTimerApplied with value true is configured by upper layers. If determination is valid or true, the MAC entity of the UE (100) starts or restarts the DSR-logicalChannelSR-DelayTimer. If determination is not valid or is false, the MAC entity of the UE (100) stops the DSR-logicalChannelSR-DelayTimer, if running.

[0182] Example 5:

[0183] For DSR, the MAC entity shall:

[0184] 1> if the DSR is triggered for a logical channel of the LCG for which DSR-logicalChannelSR-DelayTimerApplied with value true is configured by upper layers

[0185] 2> start or restart the DSR-logicalChannelSR-DelayTimer.

[0186] 1> else:

[0187] 2> if running, stop the DSR-logicalChannelSR-DelayTimer.

[0188] In an embodiment, a DSR manager (or DSR controller (140)) cancels a pending DSR for the at least one logical channel of the specific LCG when the configuration and / or reconfiguration of DSR functionality for the LCG disables the DSR function for the LCG.

[0189] In an embodiment, the DSR manager cancels a pending DSR for the at least one logical channel of the specific LCG when the configuration and / or reconfiguration of DSR functionality for the LCG releases the DSR configuration for the LCG.

[0190] In an embodiment, the DSR manager cancels a pending DSR for the at least one logical channel of the specific LCG is cancelled when at least one parameter related to the DSR triggering and / or DSR transmission in the configuration and / or reconfiguration of DSR functionality for the LCG is at least one of changed / modified (e.g. a change for the corresponding value, range, applicability, identity, index, activation, deactivation, status) or added or removed. The parameter related to the DSR triggering and / or DSR transmission in the configuration and / or reconfiguration of DSR functionality for the LCG may include at least one of the following:

[0191] a) Logical Channel Group (LCG) identity (also termed as, LCG-Id);

[0192] b) Remaining Time threshold (also termed as, remainingTimeThreshold);

[0193] c) logicalChannelSR-DelayTimerApplied (or DSR-logicalChannelSR-DelayTimerApplied);

[0194] d) LogicalChannelSR-DelayTimer (or DSR- LogicalChannelSR-DelayTimer);

[0195] e) logicalChannelSR-Mask (or DSR- logicalChannelSR-Mask);

[0196] f) Logical Channel Prioritization (LCP) restrictions configuration; and

[0197] g) Scheduling Request (SR) configuration parameters for the logical channel (or logical channel group) including periodicity, type, priority, association to critical / emergency / low latency service.

[0198] FIGURE 2 illustrates various hardware components of the UE (100), according to embodiments as disclosed herein. In an embodiment, the UE (100) includes a processor (110), a communicator (120), a memory (130), and a DSR controller (140). The processor (110) is coupled with the communicator (120), the memory (130), and the DSR controller (140).

[0199] The DSR controller (140) determine that the PDCP SDU has not been transmitted in the MAC PDU, the PDCP SDU is associated with the Logical Channel of the LCG that triggers the DSR, and the PDCP SDU is a delay-critical PDCP SDU wherein the remaining value of the PDCP discard Timer associated with the PDCP SDU is below the remaining time threshold value. Based on the determination, the DSR controller (140) associate the at least one PDCP SDU with the DSR.

[0200] In an embodiment, the DSR controller (140) determines the MAC PDU cannot accommodate the SDU associated with the pending DSR. Based on the determination, the DSR controller (140) performs that the MAC entity of the UE (100) includes the DSR MAC CE in the MAC PDU. The DSR MAC CE is a complete DSR MAC CE. The complete DSR MAC CE comprises delay information for all the SDUs associated with all the pending DSRs. The delay information comprises the remaining time and the buffer size. The DSR MAC CE is prioritized over the SDU associated with the pending DSR for inclusion in the MAC PDU, when the MAC PDU cannot accommodate together the DSR MAC CE and the SDU associated with the pending DSR.

[0201] In an embodiment, the DSR controller (140) determines uplink resources accommodating all SDUs associated with the DSR for transmission. Based on the determination, the DSR controller (140) cancels the at least one pending DSR. The at least one pending DSR can be the at least one triggered DSR.

[0202] In an embodiment, the DSR controller (140) determines that the uplink grant accommodates all the SDUs associated with the corresponding pending DSR in the MAC PDU and the MAC PDU is transmitted. Based on the determination, the DSR controller (140) cancels the pending DSR. In an embodiment, the DSR controller (140) determines that all the SDUs associated with the corresponding pending DSR are discarded. Based on the determination, the DSR controller (140) cancels the pending DSR.

[0203] In an embodiment, the DSR controller (140) triggers the DSR and the SR for the DSR after an assembly of an MAC PDU that contains a DSR MAC CE but before a transmission of the MAC PDU.

[0204] In an embodiment, the DSR controller (140) triggers the DSR and the SR for the DSR during the MAC PDU assembly.

[0205] In an embodiment, the DSR controller (140) determines the configuration associated with the DSR functionality and the reconfiguration associated with the DSR functionality for the LCG at least one of: disables the DSR function for the LCG and releases the DSR function for the LCG. Based on the determination, the DSR controller (140) cancels the pending DSR for the at least one logical channel of the LCG.

[0206] Further, the DSR controller (140) determines the condition is met. Based on the determination, the DSR controller (140) stops the ongoing random access procedure that was initiated due to the pending SR for the DSR. The pending SR has no valid PUCCH resources configured.

[0207] In an embodiment, the condition is that the DSR that triggered the SR has been cancelled due to at least one of: the configuration associated with the DSR functionality and the reconfiguration of the DSR functionality for the LCG that disables the DSR function or releases the DSR configuration for the LCG. In another embodiment, the condition is that the at least one DSR that triggered the SR has been cancelled due to the configuration associated with the DSR functionality and the reconfiguration associated with the DSR functionality for the LCG that changes a DSR parameter that affects DSR triggering or DSR transmission,

[0208] In another embodiment, the condition is that the DSR that triggered the SR has been cancelled when all the SDUs associated with the DSR have been discarded. In another embodiment, the condition is that the MAC PDU is transmitted using the UL grant other than a UL grant provided by a RAR or the UL grant for the transmission of an MSGA payload. The MAC PDU includes at least one of: all the SDUs associated with the DSR or the DSR MAC CE that includes delay information of all the SDUs associated with the DSR.

[0209] Further, the DSR controller (140) cancels the SR when the at least one DSR that triggered the SR has been cancelled due to at least one of: the configuration associated with the DSR functionality and the reconfiguration associated with the DSR functionality for the LCG that performs at least one of: disables the DSR function, releases the DSR configuration for the LCG and changes at least one DSR parameter that affects at least one of: DSR triggering and DSR transmission.

[0210] Further, the DSR controller (140) excludes the delay information in the DSR MAC CE in at least one of transmission associated with the MAC PDU and retransmission associated with the MAC PDU that pertains to the delay information for the at least one DSR that is cancelled.

[0211] Further, the DSR controller (140) updates the delay information for the at least one DSR included in the DSR MAC CE when the MAC PDU is retransmitted. The update is based on at least one of: a time elapsed between a first transmission and a retransmission, an applicability of the delay information for the at least one DSR, and a cancellation status for the at least one DSR.

[0212] The DSR controller (140) is 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 firmware.

[0213] The processor (110) may include one or a plurality of processors. The one or the plurality of processors may be a general-purpose processor, such as a central processing unit (CPU), an application processor (AP), or the like, a graphics-only processing unit such as a graphics processing unit (GPU), a visual processing unit (VPU), and / or an AI-dedicated processor such as a neural processing unit (NPU). The processor (110) may include multiple cores and is configured to execute the instructions stored in the memory (130).

[0214] In an embodiment, the memory (130) stores Physical Downlink Control Channel (PDCCH) information, Downlink Control Information (DCI) information, and Physical Downlink Shared Channel (PDSCH) information.

[0215] Further, the processor (110) is configured to execute instructions stored in the memory (130) and to perform various processes. The communicator (120) is configured for communicating internally between internal hardware components and with external devices via one or more networks. The memory (130) also stores instructions to be executed by the processor (110). The memory (130) may include non-volatile storage elements. Examples of such 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 (130) 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 that the memory (130) is non-movable. In certain examples, a non-transitory storage medium may store data that can, over time, change (e.g., in Random Access Memory (RAM) or cache).

[0216] Although FIG. 2 shows various hardware components of the UE (100) but it is to be understood that other embodiments are not limited thereon. In other embodiments, the UE (100) may include less or more number of components. Further, the labels or names of the components are used only for illustrative purposes and does not limit the scope of the invention. One or more components can be combined together to perform the same or substantially similar function in the UE (100).

[0217] FIGURE 3 illustrates a flow chart (S300) illustrating a method for handling the DSR for the XR service, according to embodiments as disclosed herein. The operations (S302 and S304) are handled by the DSR controller (140).

[0218] At S302, the method includes determining that the PDCP SDU has not been transmitted in the MAC PDU, the PDCP SDU is associated with the Logical Channel of the LCG that triggers the DSR, and the PDCP SDU is the delay-critical PDCP SDU wherein a remaining value of PDCP discard Timer associated with the at least one PDCP SDU is below a remaining time threshold value. At S304, the method includes associating the at least one PDCP SDU with the DSR based on the determination.

[0219] FIGURE 4 illustrates an example flowchart (S400) that illustrates the DSR cancellation mechanism at the MAC entity for XR in the wireless network (1000), according to embodiments as disclosed herein.

[0220] At S402, the UE (100) receives the configuration or reconfiguration of the DSR functionality for the LCG in the RRC signaling from the network entity (200). At S404, the UE (100) determines whether the configuration or reconfiguration of the DSR functionality for the LCG is at least one of disable the DSR function for the LCG and release the DSR configuration for the LCG?

[0221] The UE (100) determines that the configuration or reconfiguration of the DSR functionality for the LCG is at least one of disable the DSR function for the LCG and release the DSR configuration for the LCG then, at S406, the MAC entity of the UE (100) cancels the pending DSR for the at least one logical channel of the LCG. In another embodiment, the UE (100) does not determine that the configuration or reconfiguration of the DSR functionality for the LCG is at least one of disable the DSR function for the LCG and release the DSR configuration for the LCG, at S408, the MAC entity of the UE (100) skips to cancel the pending DSR for the at least one logical channel of the LCG.

[0222] FIGURE 5 illustrates another flowchart (S500) that illustrates the DSR triggering mechanism at the MAC entity for XR in the wireless network (1000), according to embodiments as disclosed herein.

[0223] At S502, the UE (100) receives the configuration or reconfiguration of the DSR functionality for the LCG in the RRC signaling from the network entity (200). At S504, the UE (100) determines that the configuration or reconfiguration of the DSR functionality for the LCG is at least one of the enabling the DSR function for the LCG and setting up the DSR configuration for the LCG. At S506, the MAC entity of the UE (100) triggers DSR for the at least one logical channel of the LCG based on the determination.

[0224] The proposed method ensures providing the appropriate and accurate DSR reporting to the network entity (200) that enables the effective and proper scheduling from the network entity (200) for the UE (100).

[0225] The various actions, acts, blocks, steps, or the like in the flow charts (S300-S500) may be performed in the order presented, in a different order or simultaneously. Further, in some embodiments, some of the actions, acts, blocks, steps, or the like may be omitted, added, modified, skipped, or the like without departing from the scope of the invention.

[0226] 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.

[0227] The embodiments disclosed herein describes methods and systems for providing a DSR cancellation mechanism for XR in wireless networks. Therefore, it is understood that the scope of the protection is extended to such a program and in addition to a computer readable means having a message therein, such computer readable storage means contain program code means for implementation of one or more steps of the method, when the program runs on a server or mobile device or any suitable programmable device. The method is implemented in at least one embodiment through or together with a software program written in e.g., Very high speed integrated circuit Hardware Description Language (VHDL) another programming language, or implemented by one or more VHDL or several software modules being executed on at least one hardware device. The hardware device can be any kind of portable device that can be programmed. The device may also include means which could be e.g., hardware means like e.g., an ASIC, or a combination of hardware and software means, e.g. an ASIC and an FPGA, or at least one microprocessor and at least one memory with software modules located therein. The method embodiments described herein could be implemented partly in hardware and partly in software. Alternatively, the invention may be implemented on different hardware devices, e.g., using a plurality of CPUs.

[0228] FIGURE 6 illustrates a block diagram illustrating a structure of a UE according to embodiments as disclosed herein. A UE of FIG. 6 may correspond to the UE of FIG. 2.

[0229] As shown in FIG. 6, the UE according to an embodiment may include a transceiver 610, a memory 620, and a processor (e.g. controller) 630. The transceiver 610, the memory 620, and the processor 630 of the UE may operate according to a communication method of the UE described above. However, the components of the UE are not limited thereto. For example, the UE may include more or fewer components than those described above. In addition, the processor 630, the transceiver 610, and the memory 620 may be implemented as a single chip. Also, the processor 630 may include at least one processor.

[0230] The transceiver 610 collectively refers to a UE receiver and a UE transmitter, and may transmit / receive a signal to / from a base station. The signal transmitted or received to or from the base station may include control information and data. The transceiver 610 may include a RF transmitter for up-converting and amplifying a frequency of a transmitted signal, and a RF receiver for amplifying low-noise and down-converting a frequency of a received signal. However, this is only an example of the transceiver 610 and components of the transceiver 610 are not limited to the RF transmitter and the RF receiver.

[0231] Also, the transceiver 610 may receive and output, to the processor 630, a signal through a wireless channel, and transmit a signal output from the processor 630 through the wireless channel.

[0232] The memory 620 may store a program and data required for operations of the UE. Also, the memory 620 may store control information or data included in a signal obtained by the UE. The memory 620 may be a storage medium, such as read-only memory (ROM), random access memory (RAM), a hard disk, a CD-ROM, and a DVD, or a combination of storage media.

[0233] The processor 630 may control a series of processes such that the UE operates as described above. For example, the transceiver 610 may receive a data signal including a control signal transmitted by the base station, and the processor 630 may determine a result of receiving the control signal and the data signal transmitted by the base station.

[0234] FIGURE 7 illustrates a block diagram illustrating a structure of a base station according to embodiments as disclosed herein.

[0235] As shown in FIG. 7, the base station according to an embodiment may include a transceiver 710, a memory 720, and a processor (e.g. controller) 730. The transceiver 710, the memory 720, and the processor 730 of the base station may operate according to a communication method of the base station described above. However, the components of the base station are not limited thereto. For example, the base station may include more or fewer components than those described above. In addition, the processor 730, the transceiver 710, and the memory 720 may be implemented as a single chip. Also, the processor 730 may include at least one processor.

[0236] The transceiver 710 collectively refers to a base station receiver and a base station transmitter, and may transmit / receive a signal to / from a terminal. The signal transmitted or received to or from the terminal may include control information and data. The transceiver 710 may include a RF transmitter for up-converting and amplifying a frequency of a transmitted signal, and a RF receiver for amplifying low-noise and down-converting a frequency of a received signal. However, this is only an example of the transceiver 710 and components of the transceiver 710 are not limited to the RF transmitter and the RF receiver.

[0237] Also, the transceiver 710 may receive and output, to the processor 730, a signal through a wireless channel, and transmit a signal output from the processor 730 through the wireless channel.

[0238] The memory 720 may store a program and data required for operations of the base station. Also, the memory 720 may store control information or data included in a signal obtained by the base station. The memory 720 may be a storage medium, such as read-only memory (ROM), random access memory (RAM), a hard disk, a CD-ROM, and a DVD, or a combination of storage media.

[0239] The processor 730 may control a series of processes such that the base station operates as described above. For example, the transceiver 710 may receive a data signal including a control signal transmitted by the terminal, and the processor 730 may determine a result of receiving the control signal and the data signal transmitted by the terminal.

[0240] 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 modificationsshouldand 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 preferred embodiments, those skilled in the art will recognize that the embodiments herein can be practiced with modification within the scope of the embodiments as described herein.

Claims

1.A user equipment (UE) in a wireless communication system, the UE comprising:a transceiver; anda controller coupled with the transceiver, and configured to:in case that a first smallest remaining value of packet data convergence protocol (PDCP) discard timers among all PDCP service data units (SDUs) becomes below a remaining time threshold of a logical channel group (LCG), trigger a delay status report (DSR) for a logical channel, andin case that an SDU has not been transmitted in any medium access control (MAC) protocol data unit (PDU) and is associated with the logical channel which triggered the DSR, identify that the SDU is associated with the DSR.2.The UE of claim 1, wherein the DSR is cancelled when all PDCP SDUs associated with the DSR have been discarded.3.The UE of claim 1, wherein the DSR is cancelled when a MAC PDU is transmitted and the MAC PDU includes all PDCP SDUs associated with the DSR.4.The UE of claim 1, wherein the DSR is cancelled when a MAC PDU is transmitted and the MAC PDU includes a DSR MAC control element (CE) that contains delay information of all PDCP SDUs associated with the DSR.5.The UE of claim 4, wherein the DSR MAC CE includes delay information associated with pending DSRs when the MAC PDU includes the DSR MAC CE.6.The UE of claim 4, wherein the DSR MAC CE includes a remaining time field indicating a shortest remaining value of PDCP discard timer among all PDCP SDUs buffered for the LCG but have not been transmitted in any MAC PDU at a time of a first symbol of a first physical uplink shared channel (PUSCH) transmission including the DSR MAC CE.7.A method performed by a user equipment (UE) in a wireless communication system, the method comprising:in case that a first smallest remaining value of packet data convergence protocol (PDCP) discard timers among all PDCP service data units (SDUs) becomes below a remaining time threshold of a logical channel group (LCG), triggering a delay status report (DSR) for a logical channel; andin case that an SDU has not been transmitted in any medium access control (MAC) protocol data unit (PDU) and is associated with the logical channel which triggered the DSR, identifying that the SDU is associated with the DSR.8.The method of claim 7, wherein the DSR is cancelled when all PDCP SDUs associated with the DSR have been discarded.9.The method of claim 7, wherein the DSR is cancelled when a MAC PDU is transmitted and the MAC PDU includes all PDCP SDUs associated with the DSR.10.The method of claim 7, wherein the DSR is cancelled when a MAC PDU is transmitted and the MAC PDU includes a DSR MAC control element (CE) that contains delay information of all PDCP SDUs associated with the DSR.11.The method of claim 10, wherein the DSR MAC CE includes delay information associated with pending DSRs when the MAC PDU includes the DSR MAC CE.12.The method of claim 10, wherein the DSR MAC CE includes a remaining time field indicating a shortest remaining value of PDCP discard timer among all PDCP SDUs buffered for the LCG but have not been transmitted in any MAC PDU at a time of a first symbol of a first physical uplink shared channel (PUSCH) transmission including the DSR MAC CE.

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