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

Abstract

The present disclosure relates to a 5G or 6G communication system for supporting higher data transmission rates. Embodiments disclosed herein describe a method and a user equipment (UE) for latency status reporting (DSR) handling for extended reality (XR) within a communication network system. The method involves the UE detecting a transmission of a medium access control (MAC) protocol data unit (PDU) or a cancellation of a DSR that triggered a scheduling request (SR) for the DSR. The UE stops an ongoing random access procedure initiated due to the SR for the DSR, wherein the SR for the DSR lacks a configuration of a valid physical uplink control channel (PUCCH) resource. The solution provides an enhanced DSR handling mechanism that ensures efficient transmission and better scheduling for XR applications in a wireless network.

Description

Technical Field

[0001] This application relates to communication network systems, and more specifically to delay status reporting (DSR) processing for extended reality (XR) in communication network systems. Background Technology

[0002] 5G mobile communication technology defines a wide frequency band, enabling high transmission rates and new services. It can be implemented not only in "sub-6GHz" bands such as 3.5GHz, but also in "above-6GHz" bands, including 28GHz and 39GHz, known as millimeter waves. Furthermore, to achieve transmission rates 50 times faster than 5G and ultra-low latency one-tenth that of 5G, 6G mobile communication technology (referred to as "super 5G systems") in terahertz bands (e.g., the 95GHz to 3THz band) has been considered.

[0003] In the early stages of 5G mobile communication technology, to support services related to enhanced mobile broadband (eMBB), ultra-reliable and low-latency communication (URLLC), and massive machine-type communication (mMTC) and to meet the performance requirements associated with these technologies, standardization work has been underway in the following areas: beamforming and massive MIMO for mitigating radio wave path loss and increasing radio wave transmission distance in millimeter waves; parameter sets for efficient utilization of millimeter wave resources and dynamic operation of time slot formats (e.g., operating multiple subcarrier spacings); initial access technologies to support multi-beam transmission and the definition and operation of broadband, BWP (bandwidth portion); new channel coding methods such as LDPC (low-density parity-check) codes for high-capacity data transmission and polar codes for highly reliable transmission of control information; L2 preprocessing; and network slicing for providing dedicated networks tailored to specific services.

[0004] Currently, considering the services that 5G mobile communication technology will support, discussions are underway regarding improvements and performance enhancements to the initial 5G mobile communication technology. Physical layer standardization already exists for technologies such as: Vehicle-to-Everything (V2X) for assisting autonomous vehicles in making driving decisions based on information sent by the vehicle about its location and status and for enhancing user convenience; New Radio Unlicensed (NR-U) designed to ensure system operation in accordance with various regulatory requirements in unlicensed frequency bands; NR UE power saving; Non-Terrestrial Network (NTN) (i.e., UE-satellite direct communication for ensuring coverage in areas where communication with terrestrial networks is unavailable); and positioning.

[0005] Furthermore, standardization is underway in the wireless interface architecture / protocol domain for technologies such as: Industrial Internet of Things (IIoT) to support new services through interoperability and convergence with other industries; IAB (Integrated Access and Backhaul) for nodes to provide network service area extension by supporting wireless backhaul and access links in an integrated manner; mobility enhancements including conditional handover and DAPS (Dual Active Stack) handover; and two-step random access (2-step RACH for NR) to simplify the random access process. Standardization is also underway in the system architecture / service domain, involving 5G baseline architectures (e.g., service-based architectures or service-based interfaces) for combining Network Functions Virtualization (NFV) and Software-Defined Networking (SDN) technologies, and mobile edge computing (MEC) for UE location-based reception services.

[0006] As 5G mobile communication systems become commercialized, the already exponentially growing number of connected devices will be linked to these networks, necessitating enhanced functionality and performance of 5G systems, as well as integrated operation of connected devices. To this end, new research is planned for the following related areas: effectively supporting extended reality (XR) such as augmented reality (AR), virtual reality (VR), and mixed reality (MR); improving 5G performance and reducing complexity by leveraging artificial intelligence (AI) and machine learning (ML); AI service support; metaverse service support; and drone communication.

[0007] Furthermore, this development of 5G mobile communication systems will lay the foundation for the development of technologies including: new waveforms to ensure terahertz band coverage for 6G mobile communication technologies; full-dimensional MIMO (FD-MIMO); multi-antenna transmission technologies (such as array antennas and large antennas); metamaterial-based lenses and antennas to improve terahertz band signal coverage; high-dimensional spatial multiplexing technologies using orbital angular momentum (OAM); reconfigurable smart surfaces (RIS); full-duplex technologies to improve the frequency efficiency of 6G mobile communication technologies and improve system networks; AI-based communication technologies to achieve system optimization by utilizing satellites and AI (artificial intelligence) from the design stage and incorporating end-to-end AI support; and next-generation distributed computing technologies to achieve services with complexity exceeding the operational limits of UEs by utilizing ultra-high-performance communication and computing resources.

[0008] XR is an overarching term encompassing all immersive technologies, including Virtual Reality (VR), Augmented Reality (AR), and Mixed Reality (MR), which merge the physical and digital worlds to create interactive, immersive experiences. These technologies are essential for realizing the concept of digital twins or metaverses and are a crucial component of fifth-generation (5G) and 5G-Advanced communication network systems. 3GPP Release 18 continues the development of 5G-Advanced, aiming to improve 5G networks to support more demanding use cases, including XR. Release 18 focuses on optimizing 5G networks to meet the requirements of XR, including real-time immersive experiences, ultra-low latency, and high data rates.

[0009] Integrating XR services into existing and future wireless networks presents numerous challenges. The task is to adapt the 3GPP New Radio (NR) framework supporting XR to the demanding requirements of these applications, such as high data rates, ultra-low latency, and power-efficient connectivity. As XR applications become more prevalent, the pressure on network infrastructure to effectively manage these requirements intensifies.

[0010] In existing mechanisms, the Buffer Status Report (BSR) process is used to transmit the status of buffered data across different Logical Channel Groups (LCGs), such as the size of the buffered data. The network scheduler uses the BSR to determine the uplink clearance allocated to a User Equipment (UE) for transmitting this buffered data. However, one of the key challenges is that the BSR does not include any information about the latency status of the buffered data. Buffered data at the UE can have different latency levels because data storage at the buffer can occur at different points in time. Furthermore, different types of services have different packet delay budgets, which specify the maximum amount of latency that data can experience before it is discarded. If buffered data exceeds its packet delay budget or exceeds the time limit configured for data transmission, the data must be discarded.

[0011] If a Service Data Unit (SDU) expires before it can be sent or when the successful delivery of the SDU is acknowledged by a peer PDCP entity (e.g., via a PDCP status report), the SDU is discarded. This lack of latency information in the existing BSR process leads to scheduling inefficiencies, particularly for latency-sensitive applications that rely on fast and timely data transmission. While the BSR reports the size of the buffered data, this size does not provide information about how long the data has been waiting in the buffer, a factor the network needs to determine whether it can still be sent without violating the latency budget.

[0012] To address the limitations of existing BSR mechanisms, Delay Status Reporting (DSR) has been introduced. DSR combines latency information with associated buffered data to enable the network to make better scheduling decisions for latency-sensitive applications such as XR. However, one of the main challenges of DSR is the potential insufficient availability of uplink resources. DSR requires more bandwidth and resources to transmit not only data information but also additional latency information. In some scenarios, when uplink resources are unavailable, a random access procedure is initiated, which the UE uses to gain network access. However, managing the random access procedure for different conditions associated with it is necessary, and this has not yet been addressed in the 3GPP specifications.

[0013] Therefore, it is desirable to address the aforementioned shortcomings or other disadvantages, or at least provide a useful alternative. Summary of the Invention

[0014] Solution to the problem

[0015] The primary objective of this disclosure is to provide a method and a UE for delay status reporting processing for XR in a communication network system.

[0016] Another object of this disclosure is to fully transmit the DSR Media Access Control (MAC) Control Element (CE) and its subheadings when there is at least one DSR pending and when the uplink shared channel (UL-SCH) resource is available for a new transmission.

[0017] Another objective of this disclosure is to stop random access because a pending scheduling request (SR) for a DSR is not configured with valid physical uplink control channel (PUCCH) resources and the associated conditions to be met.

[0018] Another object of this disclosure is to form a DSR when there is not sufficient uplink clearance available for DSR MAC CE transmission.

[0019] Another objective of this disclosure is to cancel the SR for the DSR when the DSR is canceled, and to cancel the SR for the DSR that triggered random access.

[0020] In one aspect, these objectives are achieved by providing a method and a UE for DSR processing for XR in a communication network system. The method includes the UE detecting the transmission of a MAC Protocol Data Unit (PDU) or triggering the cancellation of a DSR for an pending SR against the DSR, and stopping an ongoing random access procedure initiated due to a pending SR against the DSR, wherein the pending SR against the DSR lacks valid PUCCH resources (e.g., no PUCCH resources are configured for the UE for the SR).

[0021] In this embodiment, the UE receives an uplink (UL) grant for the MAC layer / entity. The uplink grant is used to send a MAC PDU, and the uplink grant is at least one of a configured uplink grant and a dynamic uplink grant addressing a Cell Radio Network Temporary Identifier (C-RNTI), and receiving the uplink grant causes the MAC layer / entity to terminate the ongoing random access procedure.

[0022] In an embodiment, when a MAC PDU is sent using an uplink license that is not provided by a Random Access Response (RAR) or is not determined for the transmission of the message A (MSGA) payload, the MAC PDU includes at least one of the following: all PDCP Service Data Units (SDUs) associated with the DSR, or a DSR MAC CE including delay information of all SDUs associated with the DSR.

[0023] In one embodiment, the DSR that triggered the SR is canceled when all PDCP SDUs associated with the DSR have been discarded, and the SR is triggered by the DSR process.

[0024] On one hand, these objectives are achieved by providing a UE for DSR processing of XR in a communication network system. The UE includes a memory, a processor, and a DSR controller connected to the memory and the processor. The DSR controller detects the transmission of a MAC PDU for an SR that triggers the DSR or the cancellation of the DSR. Furthermore, the DSR controller stops an ongoing random access procedure initiated due to a pending SR for the DSR, where the pending SR lacks a valid PUCCH resource configuration.

[0025] The DSR controller receives a UL grant for the MAC layer / entity. The uplink grant is used to send a MAC PDU, and the uplink grant is at least one of a configured uplink grant and a dynamic uplink grant addressed to the C-RNTI, wherein receiving the uplink grant causes the MAC layer / entity to terminate an ongoing random access procedure.

[0026] The DSR controller determines whether to send a MAC PDU using an uplink license not provided by the RAR or not determined for the transmission of the MSGA payload, wherein the MAC PDU includes at least one of the following: all PDCP SDUs associated with the DSR, or a DSR MAC CE including delay information of all SDUs associated with the DSR.

[0027] When all PDCP SDUs associated with the DSR have been discarded, the DSR controller checks that the DSR that triggered the SR has been cancelled, and the SR is triggered by the DSR process.

[0028] Before proceeding with the following detailed description, it may be advantageous to define certain words and phrases used throughout this patent document: the terms “comprising” and “including” and their derivatives mean including but not limited to; the term “or” is inclusive, referring to and / or; the phrases “associated with” and “associated with” and their derivatives may mean including, being included in, interconnected with, containing, contained within, connected to or connected to, coupled to or coupled to, able to communicate with, cooperate with, interleaved, juxtaposed, proximate, bound to or bound to, having, having the properties of, etc.; and the term “controller” means any device, system, or part thereof that controls at least one operation, such device may be implemented in hardware, firmware, or software, or some combination of at least two of these. It should be noted that the functionality associated with any particular controller can be centralized or distributed, whether local or remote.

[0029] Furthermore, the various functions described below can be implemented or supported by one or more computer programs, each computer program being formed by computer-readable program code and embodied in a computer-readable medium. The terms "application" and "program" refer to one or more computer programs, software components, instruction sets, procedures, functions, objects, classes, instances, associated data, or portions thereof suitable for implementation in appropriate computer-readable program code. The phrase "computer-readable program code" includes any type of computer code, including source code, object code, and executable code. The phrase "computer-readable medium" includes any type of medium accessible by a computer, such as read-only memory (ROM), random access memory (RAM), hard disk drive, optical disc (CD), digital video disc (DVD), or any other type of storage. "Non-transitory" computer-readable media does not include wired, wireless, optical, or other communication links that transmit transient electrical or other signals. Non-transitory computer-readable media includes media in which data can be permanently stored and media in which data can be stored and later rewritten, such as rewritable optical discs or erasable memory devices.

[0030] Definitions of certain words and phrases are provided throughout this patent document, and those skilled in the art will understand that, in many cases (if not most), such definitions apply to the prior and future use of the words and phrases defined in this way. Attached Figure Description

[0031] The present disclosure is illustrated in the accompanying drawings, in which the same reference numerals denote corresponding parts in the various drawings. Embodiments herein will be better understood from the following description with reference to the accompanying drawings, wherein:

[0032] Figure 1 A UE for enhanced DSR processing for XR in a communication network system is shown according to embodiments disclosed herein;

[0033] Figure 2 A flowchart is shown of a method for enhanced DSR processing for XR in a communication network system according to embodiments disclosed herein;

[0034] Figure 3 A flowchart is shown of a method for an enhanced random access procedure stopping method incorporating DSR cancellation at the MAC layer / entity for XR in a communication network system, according to embodiments disclosed herein;

[0035] Figure 4 A flowchart is shown of a method for initiating a random access procedure and canceling a pending SR for a DSR, according to an embodiment disclosed herein.

[0036] Figure 5 A flowchart is shown of a method for initiating a random access procedure based on the priority level of an LCG due to pending SRs for different DSRs, according to an embodiment disclosed herein.

[0037] Figure 6 A flowchart is shown of a method for transmission of a complete DSR MAC CE according to an embodiment disclosed herein;

[0038] Figure 7 A flowchart is shown of a method for transmission of a partial DSR MAC CE according to an embodiment disclosed herein;

[0039] Figure 8 The structure of a UE according to an embodiment of this disclosure is shown; and

[0040] Figure 9 The structure of a base station according to an embodiment of the present disclosure is shown. Detailed Implementation

[0041] The following discussion Figures 1 to 9 The various embodiments described in this patent document to illustrate the principles of this disclosure are for illustrative purposes only and should not be construed as limiting the scope of this disclosure in any way. Those skilled in the art will understand that the principles of this disclosure can be implemented in any suitably arranged system or device.

[0042] The embodiments described herein, along with their various features and advantageous details, are explained more fully with reference to the non-limiting embodiments illustrated in the accompanying drawings and detailed in the following description. Descriptions of well-known components and processing techniques have been omitted to avoid unnecessarily obscuring the embodiments herein. Furthermore, the various embodiments described herein are not necessarily mutually exclusive, as some embodiments may be combined with one or more other embodiments to form new embodiments. Unless otherwise stated, the term "or" as used herein means non-exclusive or. The examples used herein are intended only to facilitate understanding of how the embodiments described herein can be practiced and to further enable those skilled in the art to practice the embodiments described herein. Therefore, these examples should not be construed as limiting the scope of the embodiments described herein.

[0043] As is known in the art, embodiments can be described and illustrated based on blocks that perform one or more of the described functions. These blocks (which may be referred to herein as managers, units, modules, hardware components, etc.) are physically implemented by analog and / or digital circuitry (such as logic gates, integrated circuits, microprocessors, microcontrollers, memory circuits, passive electronic components, active electronic components, optical components, hardwired circuitry, etc.) and may optionally be driven by firmware and software. The circuitry may be embodied, for example, in one or more semiconductor chips or on a substrate support such as a printed circuit board. The circuitry constituting a block may be implemented by dedicated hardware, by a processor (1001) (e.g., one or more programmed microprocessors and associated circuitry), or by a combination of dedicated hardware (for performing certain functions of the block) and a processor (for performing other functions of the block). Without departing from the scope of this disclosure, each block of an embodiment may be physically divided into two or more interacting and discrete blocks. Similarly, without departing from the scope of this disclosure, the blocks of an embodiment may be physically combined into more complex blocks.

[0044] The accompanying drawings are provided to aid in the easy understanding of the various technical features, and it should be understood that the embodiments presented herein are not limited to the drawings. Therefore, except for those specifically set forth in the drawings, this disclosure should be construed as extending to any modifications, equivalents, and substitutions. Although the terms first, second, etc., may be used herein to describe various elements, these elements should not be limited by these terms. These terms are generally used only to distinguish one element from another.

[0045] In the rapidly evolving landscape of wireless communications, the integration of XR applications presents unique challenges, particularly in ensuring timely data delivery and efficient network resource utilization. XR applications, encompassing AR, VR, and MR, demand high data throughput and low latency to provide a seamless user experience. Existing systems, as defined in the 3GPP TS 38.321 V18.0.0 standard, attempt to address these requirements through delay status reporting (DSR) mechanisms. However, these systems have significant limitations that can hinder the performance of XR applications, especially when there are insufficient uplink resources available to accommodate DSRs and when random access procedures need to be managed for different conditions associated with the DSR process.

[0046] Network scheduling is used to allocate resources for data transmission from the UE. The network needs to know how much buffering has accumulated at the UE and the tolerable latency of the buffered data. A UE can be configured with many LCGs, and different applications can be mapped to different LCGs. The UE can transmit this information related to the relevant LCG. A DSR has a structure that can transmit LCG-specific latency and buffering information. A DSR occupies some space, and if the UE doesn't even have the resources to send the DSR itself, an SR is triggered. An SR is a message sent by the UE to request uplink resources from the network, and it is sent via the PUCCH. The PUCCH is the physical uplink control channel used by the UE to send various types of control information, including SRs. However, if resources are not configured for SRs, the UE cannot send SRs and a random access procedure is triggered.

[0047] In existing 5G systems, when a UE needs to send data, a random access procedure is employed to allow the UE to establish initial communication with the network and / or achieve time synchronization. This procedure begins when the device sends a random access preamble (MSG1), and the network responds to the preamble with a random access response (RAR or MSG2), while simultaneously granting the device uplink resources to continue communication. The device then sends a Radio Resource Control (RRC) Connection Request message or message 3 (MSG3) to confirm the connection. Furthermore, the network provides an RRC Connection Establishment (MSG4) and grants the requested resources to the device. In addition to the four-step random access procedure, there is a two-step random access procedure, where MSG1 and MSG3 are aggregated in the MSGA, and MSG2 and MSG4 are aggregated in the MSGB.

[0048] To overcome these limitations, the provided disclosure introduces an enhanced method and UE for XR-customized latency state report processing in a wireless network that requires extremely low latency performance and high-quality data throughput. The method involves stopping random access procedures triggered by pending SRs for Extended Reality (DSR) in the wireless network. By stopping the random access procedures, the system avoids unnecessary network congestion and ensures more efficient resource utilization. XR applications require extremely low latency performance and high-quality data throughput and are particularly sensitive to latency or interruptions in service.

[0049] The existing mechanism, as outlined in 3GPP TS 38.321, is designed to handle uplink resources and latency-sensitive applications in wireless networks. However, it faces several significant drawbacks when there are insufficient uplink resources available for transmitting DSRs, or when random access procedures initiated due to pending SRs for DSRs are affected by different conditions of the DSR procedure. Uplink licensing is the allocation of uplink resources provided by the network to the UE, allowing the UE to transmit data to the network.

[0050] The embodiments disclosed herein provide a system and method for DSR processing for XR in a communication network system. The provided method includes stopping a random access procedure triggered by a SR for the DSR. Furthermore, the method includes forming a DSR when there is insufficient uplink clearance available for DSR MAC CE transmission.

[0051] Therefore, embodiments of this document provide a method and system for packet dropping processing in extended reality in wireless networks.

[0052] However, the existing mechanism (i.e., 3GPP TS 38.321) has some drawbacks when there are not enough uplink resources available to accommodate DSRs and when the random access procedure is stopped due to DSR cancellation.

[0053] Unlike traditional systems and methods, the proposed method provides an enhanced DSR processing mechanism for XR in wireless networks.

[0054] Now refer to the attached diagram, for more specific details. Figures 1 to 7 A preferred embodiment is shown.

[0055] Figure 1 A UE (100) for an enhanced DSR processing mechanism for XR in a communication network system is shown. In an embodiment, the UE (100) includes a processor (101), a memory (102), a communicator (103), and a DSR controller (104).

[0056] Examples of wireless communication network systems include, but are not limited to, cellular networks (such as 2G, 3G, 4G, 5G, B5G / 6G or advanced cellular networks), local area networks (LANs) (such as Wi-Fi, Li-Fi, etc.), personal area networks (PANs) (such as Bluetooth, Zigbee, Z-Wave, etc.), wide area networks (WANs) (such as satellite communication networks, long-range WANs, narrowband IoT, low-bandwidth communication for IoT, etc.), metropolitan area networks (MANs), machine-to-machine (M2M) networks, self-organizing and mesh networks, and emerging and advanced networks.

[0057] Examples of UE (100) may include, but are not limited to, consumer electronics (such as mobile phones and smartphones), tablets, wearable devices, televisions, computing devices (such as laptops, notebook computers, desktops, workstations, etc.), IoT devices, automotive systems (such as connected cars, autonomous vehicles, vehicle-to-everything (V2X) communication devices, etc.), enterprise devices such as robots, specialized devices (such as medical devices, public safety devices, etc.), and media devices (such as game consoles, streaming media devices, etc.).

[0058] In addition, the UE (100) is equipped with sensors and interfaces, including accelerometers, gyroscopes, cameras, and microphones, to support XR applications such as AR, VR, and MR. These applications require high data rates and low latency. The UE (100) also supports edge computing, offloading intensive tasks to nearby servers to reduce processing load and latency. Accelerometers and gyroscopes ensure accurate motion tracking and orientation detection for seamless XR experiences. These sensors detect subtle movements, enhancing interactivity. In VR, gyroscopes track head movements for natural navigation, while in AR, accelerometers help to accurately overlay digital information. Cameras and microphones further enhance XR capabilities by providing visual and auditory input. Cameras capture real-world visuals for AR, ensuring clear digital overlays. Microphones enable voice commands and spatial audio. In MR, spatial audio provides directional sound cues, making virtual elements feel real.

[0059] The UE (100) includes the protocol stack of the mobile communication network system, such as the PDCP layer / entity (105), RLC layer / entity (106), MAC layer / entity (107), and physical (PHY) layer / entity (108). The PDCP layer / entity (105) is responsible for header compression, encryption, and integrity protection of data packets to ensure secure and efficient data transmission. The RLC layer (106) manages the segmentation and reassembly of data packets, as well as error correction through the Automatic Repeat Request (ARQ) mechanism, which is used to maintain data integrity in XR applications. The MAC layer (107) handles the scheduling and prioritization of data packets, coordinating access to the shared radio medium to optimize network resource utilization. The PHY layer (108) is responsible for signal modulation and demodulation, as well as the transmission and reception of data through the air interface, utilizing advanced techniques such as Orthogonal Frequency Division Multiplexing (OFDM) and beamforming to enhance signal quality and coverage.

[0060] The processor (101) is responsible for executing instructions and managing the overall operation of the UE (100), including an enhanced SDU discard mechanism. The processor (101) communicates with the memory (102), the communicator (103), and the DSR controller (104). The processor (101) is configured to execute instructions stored in the memory (102) and perform various processes for real-time data processing in XR applications. The processor (101) may include one or more processors, which may be general-purpose processors such as a central processing unit (CPU), an application processor (AP), etc., graphics-only units such as a graphics processing unit (GPU), a vision processing unit (VPU), and / or artificial intelligence (AI) dedicated processors such as a neural processing unit (NPU).

[0061] The memory (102) stores the operating system, application software, and temporary data used by the processor (101). The memory (102) stores Physical Downlink Control Channel (PDCCH) information, Downlink Control Information (DCI) information, and Physical Downlink Shared Channel (PDSCH) information. The memory (102) stores instructions to be executed by the processor (101). The memory (102) may include non-volatile storage elements. Examples of such non-volatile storage elements may include magnetic hard disks, optical disks, floppy disks, flash memory, or electrically programmable memory (EPROM) or electrically erasable programmable memory (EEPROM). Additionally, in some examples, the memory (102) may be considered a non-transitory storage medium. The term non-transitory may indicate that the storage medium is not embodied in a carrier or propagating signal. However, the term non-transitory should not be construed as meaning that the memory (102) is immovable. In some examples, the memory (102) may be configured to store a larger amount of information than a standard memory. In the example, non-transitory storage media can store data that can change over time (e.g., in random access memory (RAM) or cache).

[0062] The communicator (103) facilitates wireless communication with a network, supports various communication protocols such as LTE, 5G, 6G, and Wi-Fi, and may include multiple antennas for multiple-input multiple-output (MIMO) operation to enhance data throughput and reliability. Furthermore, the communicator (103) is configured for internal communication between internal hardware components and with external devices (client devices) via one or more networks. The communicator (103) includes electronic circuitry specific to standards that enable wired or wireless communication.

[0063] The DSR controller (104) is dedicated hardware designed to handle DSR transmissions, ensuring XR data streams are delivered with minimal latency and packet loss. The DSR controller (104) detects the transmission of MAC PDUs from the UE (100) to the network at the MAC layer / entity (107), which encapsulate user data (PDCP SDUs) and / or control information (DSR MAC CEs). It also detects the cancellation of a DSR that triggered an SR for the DSR. Upon detection, if the pending SR for the DSR lacks a valid PUCCH resource configuration, the DSR controller (104) halts the ongoing random access procedure initiated due to the pending SR for the DSR. This ensures that the UE (100) does not waste resources on the random access procedure because the MAC PDU has already been sent to the network, or the DSR that triggered the SR has been cancelled and no PDCP SDUs are available for transmission to the network.

[0064] The DSR controller (104) receives an uplink grant from the MAC layer / entity (107) for transmitting MAC PDUs. The uplink grant may be at least one of a configured uplink grant or a dynamic uplink grant addressing to a C-RNTI. Receiving the uplink grant causes the MAC layer / entity (107) to terminate the ongoing random access procedure. The configured uplink grant pre-allocates uplink resources to the UE (100) for transmission at regular intervals. If the grant can accommodate all PDCP SDUs associated with the DSR or carry a DSR MAC CE that transmits delay information for all SDUs associated with the DSR, the DSR controller (104) stops the ongoing random access procedure.

[0065] The dynamic uplink grant addressing to the C-RNTI dynamically allocates uplink resources to a specific UE (100) based on current service requirements and network conditions. When the grant is used to transmit all PDCP SDUs associated with the DSR or to transmit the DSR MAC CE for delay information of all SDUs associated with the DSR, the DSR controller (104) stops the ongoing random access procedure.

[0066] In this embodiment, the DSR controller (104) ensures that the transmission of the MAC PDU can be performed using an uplink license that is not provided by the RAR or is not determined for the transmission of the MSGA payload. In this case, the MAC PDU may include all PDCP SDUs or DSR MAC CEs associated with the DSR, where the PDCP SDU is a data packet to be transmitted received from a higher layer, and the DSR MAC CE includes delay information for all PDCP SDUs associated with the DSR. When a valid UL license other than that provided by the RAR message or determined for the transmission of the MSGA payload is available for transmitting the MAC PDU, the random access procedure need not continue, thus ensuring that resources are not wasted.

[0067] When all PDCP SDUs associated with the DSR have been discarded, the DSR controller (104) also cancels the DSR procedure for the uplink resource SR. By canceling the DSR procedure when the associated PDCP SDU is discarded, the network avoids allocating resources for data transmissions that are no longer needed.

[0068] The DSR controller (104) determines that the DSR MAC CE generated by the UE (100) cannot be accommodated in the uplink resources granted by the network. When no pending SR for the same logical channel for the LCG is triggered by the DSR procedure, the SR for the DSR is triggered, and when there is no valid PUCCH resource configuration for requesting resources for sending the SR for the DSR, the DSR controller (104) initiates a random access procedure for the pending SR for the DSR, and cancels the pending SR for the DSR because the random access procedure is responsible for the resource request.

[0069] The DSR controller (104) checks existing pending SRs for the same logical channel. When there are no pending SRs, a new SR can be triggered for a different DSR associated with the same logical channel. The priority of the LCG associated with the pending SR is checked by the DSR controller (104) and compared with the priority of the LCG in the ongoing random access procedure. If the LCG associated with the pending SR for a different DSR has a higher priority than the LCG associated with the ongoing random access procedure, the DSR controller (104) triggers a new SR for the different DSR. Otherwise, if the LCG associated with the pending SR for a different DSR has a lower priority than the LCG associated with the ongoing random access procedure, the DSR controller (104) avoids initiating a new random access procedure and continues the ongoing random access procedure, provided that the DSR has a higher priority LCG than the pending SR for the different DSR.

[0070] When no valid PUCCH resource is configured for a new SR, the DSR controller (104) cancels new SRs for different DSRs on the same logical channel for the LCG, because the PUCCH resources are used by the UE (100) to transmit control information such as SRs. Without these resources, the UE (100) cannot initiate an SR for the DSR. Despite the lack of PUCCH resources, the DSR controller (104) does not initiate a new random access procedure for the new SR while a previous random access procedure is in progress.

[0071] When the associated DSR is cancelled, the DSR controller (104) cancels the pending SR for the DSR. This cancellation occurs when the uplink grant can accommodate a MAC PDU that includes all SDUs associated with the DSR (meaning the uplink resources allocated to the UE (100) process the transmission of all SDUs that are part of the DSR) or a DSR MAC CE that includes delay information for all SDUs associated with the DSR. The DSR process is considered complete and cancelled when the delay information, including a remaining time field and a buffer size field, is successfully transmitted. The remaining time field indicates how much time remains before the SDUs are ready to be transmitted, and the buffer size field indicates how much data is waiting to be transmitted in the buffer. If all SDUs associated with the DSR are discarded, the DSR process is no longer necessary, and the DSR controller (104) cancels the triggered DSR.

[0072] The DSR controller (104) determines that at least one DSR is pending and that UL-SCH resources are available for a new transmission. The DSR controller (104) then determines whether the available UL-SCH resources can fully accommodate the DSR MAC CE as a result of logical channel prioritization, along with its sub-header. Upon successful determination, the DSR controller (104) instructs a multiplexing and assembly process to generate the DSR MAC CE. This process ensures that delay information for all LCGs with pending DSRs is included in the DSR MAC CE. The DSR controller (104) sends the generated complete DSR MAC CE along with its sub-header, which contains delay information for all pending DSRs for the corresponding LCG. However, if the DSR controller (104) determines that the complete DSR MAC CE cannot be accommodated in uplink resources, and if no pending SR has been triggered by the DSR process for the same logical channel as that DSR, the MAC layer / entity (107) of the UE (100) triggers the SR.

[0073] The DSR controller (104) determines that a DSR is pending and that available UL-SCH resources can partially or completely accommodate a DSR MAC CE plus its sub-header. When resources are limited, logical channel prioritization plays a crucial role in determining which logical channel and associated DSR to process first. Upon successful determination, the DSR controller (104) instructs a multiplexing and assembly process to generate a DSR MAC CE and sends the generated full DSR MAC CE plus its sub-header, which contains delay information for all LCGs with pending DSRs, with the pending DSRs contained within the DSR MAC CE. Alternatively, the DSR controller (104) instructs a multiplexing and assembly process to generate a DSR MAC CE and sends a partial DSR MAC CE generated for at least one of the pending DSRs for the corresponding LCG, and cancels the DSR contained within the DSR MAC CE. For any remaining pending DSRs that have not been canceled and for which no pending SR has been triggered by the DSR process for the LCG, the DSR controller (104) triggers the SR.

[0074] In the embodiments, one or more permutations or combinations of the embodiments further described in this disclosure can be used for the DSR processing mechanism.

[0075] Figure 2 A flowchart (200) is shown of a mechanism for enhanced DSR processing for XR in a communication network system according to embodiments disclosed herein.

[0076] In step 201, the random access procedure is in progress because there is no pending SR for DSR with a configured valid PUCCH resource.

[0077] In step 202, the UE (100) receives an uplink license and sends a MAC PDU using a UL license other than the UL license provided by the Random Access Response (RAR) or the UL license used for the MSGA payload, or has discarded all PDCP SDUs associated with the DSR.

[0078] In an embodiment, the MAC layer / entity (107) of the UE (100) may stop the ongoing random access procedure due to a pending SR for the DSR that has no configured valid PUCCH resources if at least one of the following conditions is met:

[0079] 1) Use a UL license other than the uplink (UL) license provided by the Random Access Response (RAR) or the UL license determined for the transmission of the MSGA payload as specified in the 3GPP standard specification to send a MAC PDU, and the PDU includes all SDUs associated with the DSR or the DSR MAC CE, which contains delay information for all SDUs associated with the DSR.

[0080] 2) When all SDUs associated with the DSR have been discarded, the DSR that triggered the SR has been cancelled.

[0081] In the embodiments, a standard example is provided for handling a random access procedure due to a pending SR for a DSR, where the pending SR does not have a configured valid PUCCH resource, as follows:

[0082] Example 1:

[0083] MAC entity (107) may stop (if any) an ongoing random access procedure due to a pending SR for a DSR that is not configured with a valid PUCCH resource if the following conditions exist:

[0084] 1) Transmit a MAC PDU using a UL license other than the UL license provided by the random access response or the UL license determined for the transmission of the MSGA payload as specified in the 3GPP standard specification, and the PDU includes all SDUs associated with the DSR or a DSR MAC CE containing delay information for all SDUs associated with the DSR; or

[0085] 2) When all SDUs associated with the DSR have been discarded, the DSR that triggered the SR has been cancelled.

[0086] In an embodiment, the MAC entity (107) of the UE (100) may stop the ongoing random access procedure due to a pending SR for a DSR that has no configured valid PUCCH resources if at least one of the following conditions is met:

[0087] 1) The MAC PDU is transmitted using a UL license other than the UL license provided by the random access response or the UL license determined for the transmission of the MSGA payload as specified in the 3GPP standard specification, and the PDU includes a DSR MACCE, which contains delay information of all delay-critical SDUs up to (and including) the last event that triggers the DSR prior to the assembly of the MAC PDU.

[0088] 2) UL licenses can accommodate all pending data transmitted with DSR.

[0089] 3) When all SDUs associated with the DSR have been discarded, the DSR that triggered the SR has been cancelled.

[0090] In this embodiment, an example of a specification is provided for handling a random access procedure resulting from a pending SR against a DSR, where the pending SR does not have a configured valid PUCCH resource, as follows:

[0091] Example 2:

[0092] The MAC entity (107) may stop (if any) an ongoing random access procedure due to a pending SR for the DSR that is not configured with a valid PUCCH resource if the following conditions exist:

[0093] 1) The MAC PDU is transmitted using a UL license other than the UL license provided by the random access response or the UL license determined for the transmission of the MSGA payload as specified in the 3GPP standard specification, and the PDU includes a DSR MACCE, which contains delay information of all delay-critical SDUs up to (and including) the last event that triggers the DSR prior to the assembly of the MAC PDU.

[0094] 2) UL approval can accommodate all pending data transmitted in connection with DSR; or

[0095] 3) When all SDUs associated with the DSR have been discarded, the DSR that triggered the SR has been cancelled.

[0096] In this embodiment, the uplink license is at least one of a configured uplink license or a dynamic uplink license addressed to a C-RNTI. The configured uplink license includes a predefined allocation of uplink resources for the UE (100). The dynamic uplink license is provided by the network and allows the UE (100) to dynamically request resources and identify the specific UE requesting the resources. Upon receiving the uplink license, the UE (100) successfully acquires the resources for sending a MAC PDU and terminates the ongoing random access procedure.

[0097] In an embodiment, the uplink license considered for the MAC layer / entity (107) to stop an ongoing random access procedure due to a pending SR against a DSR includes a configured uplink license for which the pending SR does not have a configured valid PUCCH resource.

[0098] In an embodiment, an uplink license considered for a MAC entity to stop an ongoing random access procedure due to a pending SR against a DSR may include a configured uplink license for which the pending SR does not have a configured valid PUCCH resource.

[0099] In an embodiment, an uplink grant considered for a MAC entity to stop an ongoing random access procedure due to a pending SR against a DSR may include a dynamic uplink grant addressed to a C-RNTI, the pending SR having no configured valid PUCCH resources.

[0100] In an embodiment, uplink permission considered for a MAC entity to stop an ongoing random access procedure due to a pending SR for a DSR may include dynamic uplink permission or configured uplink permission for cells other than the cell that triggered the random access procedure (e.g., Scell, PScell), for which the pending SR does not have a configured valid PUCCH resource.

[0101] In step 203, the MAC layer / entity (107) of the UE (100) cancels the random access procedure.

[0102] Figure 3 A flowchart (300) is shown of a method for an enhanced random access procedure stopping method incorporating DSR cancellation at the MAC layer / entity (107) for XR in a communication network system according to an embodiment disclosed herein.

[0103] In step 301, a random access procedure is in progress due to a pending SR for the DSR that is not configured with a valid PUCCH resource. This involves using the random access procedure as a fallback mechanism in scenarios where an SR cannot be sent due to a lack of configured valid PUCCH resources. The initiation of the random access procedure ensures that the UE (100) can still attempt to access the network and send the necessary data even when the preferred resource is unavailable.

[0104] In step 302, the UE (100) determines whether to use a UL license other than the UL license provided by the random access response or the UL license determined for the transmission of the MSGA payload as specified in the 3GPP standard specification to transmit the MAC PDU. The UE (100) ensures that the transmitted MAC PDU includes all PDCP SDUs or DSR MAC CEs associated with the DSR, which include delay information for all SDUs associated with the DSR.

[0105] In step 303, the MAC layer / entity (107) of the UE (100) cancels the DSR and random access procedure.

[0106] In step 304, the UE (100) determines whether a valid UL license provided by the RAR or a UL license determined for the transmission of the MSGA payload as specified in the 3GPP standard specification is available for transmitting the MAC PDU. This is similar to step 302, but it specifically checks the availability of an uplink license provided by the RAR or as specified in the 3GPP standard specification.

[0107] In step 305, the MAC layer / entity (107) of the UE (100) cancels the DSR and continues the random access procedure. In an embodiment, when a MAC PDU is sent using an uplink grant provided by the random access response or an uplink grant determined for the transmission of the MSGA payload, and the PDU includes all SDUs associated with the DSR or a DSR MAC CE, the DSR MAC CE including delay information of all SDUs associated with the DSR, the pending DSR is canceled.

[0108] In step 306, the UE (100) determines whether all PDCP SDUs associated with the DSR have been discarded.

[0109] In step 307, the MAC layer / entity (107) of the UE (100) cancels the DSR and random access procedure.

[0110] In step 308, if no PDCP SDUs associated with the DSR are discarded, the UE (100) continues the random access procedure.

[0111] Figure 4 A flowchart (400) is shown of a method for initiating a random access procedure due to a pending SR for a DSR and canceling a pending SR for a DSR, according to an embodiment disclosed herein.

[0112] In step 401, the UE (100) detects the transmission of a MAC PDU, which includes all PDCPSDUs or DSR MAC CEs associated with the DSR, and the DSR MAC CE includes delay information of all PDCP SDUs associated with the DSR.

[0113] In step 402, the UE (100) determines that the DSR MAC CE cannot be accommodated in the uplink resources.

[0114] In step 403, the UE (100) determines that no pending SR has been triggered by the DSR procedure for the same logical channel of the LCG.

[0115] In step 404, the UE (100) determines that the SR to be processed does not have a valid PUCCH resource configured.

[0116] In step 405, the UE (100) initiates a random access procedure due to the pending SR for the DSR, which acts as a fallback mechanism in scenarios where the SR cannot be sent due to a lack of configured valid PUCCH resources.

[0117] In step 406, when a random access procedure is initiated due to a pending SR against a DSR that does not have a configured valid PUCCH resource, the pending SR is cancelled.

[0118] In an embodiment, when a random access procedure is initiated due to a pending SR for a DSR that does not have a configured valid PUCCH resource, the pending SR is cancelled. Furthermore, while a random access procedure is in progress, if the DSR MAC CE cannot be accommodated in uplink resources, and if there is no pending SR that has been triggered by the DSR procedure for the same logical channel up to that DSR, then the MAC layer / entity (107) of the UE (100) does not trigger an SR for the same logical channel for the LCG.

[0119] In an embodiment, when a random access procedure is initiated due to a pending SR for a DSR that does not have a configured valid PUCCH resource, the pending SR is cancelled. Furthermore, while a random access procedure is in progress, if the DSR MAC CE cannot be accommodated in uplink resources, and if there is no pending SR that has been triggered by the DSR procedure for a logical channel of the LCG up to that DSR, then the MAC layer / entity (107) of the UE (100) does not trigger any SR for any logical channel of the LCG.

[0120] In an embodiment, when a random access procedure is initiated due to a pending SR for a DSR that does not have a configured valid PUCCH resource, the pending SR is cancelled. Furthermore, during the random access procedure, if the DSR MAC CE cannot be accommodated in uplink resources, and if there is a pending SR already triggered by the DSR procedure for the same logical channel up to that DSR, the MAC layer / entity (107) of the UE (100) triggers an SR for the same logical channel for the LCG for the DSR. Additionally, if the pending SR for the DSR does not have a configured valid PUCCH resource, a new random access procedure is not initiated if a previous random access procedure has already been performed. The pending SR is cancelled when the relevant DSR is cancelled, i.e., when the uplink license can accommodate a MAC PDU including all PDCP SDUs or the DSR MAC CE associated with the DSR, the DSR MAC CE contains delay information for all SDUs associated with the DSR, or when all SDUs associated with the DSR have been discarded.

[0121] Figure 5A flowchart (500) is shown of a method for initiating a random access procedure based on the priority level of an LCG due to pending SRs for different DSRs, according to an embodiment disclosed herein.

[0122] In step 501, when a random access procedure is in progress due to a pending SR for a DSR, the pending SR for the DSR does not have a configured valid PUCCH resource, and a new random access procedure is triggered due to a pending SR for a different DSR, the UE (100) stops the current random access procedure and starts a new random access procedure. The pending SR for the different DSR is associated with an LCG / logical channel that has a higher priority than the LCG / logical channel associated with the ongoing random access procedure, and the pending SR for the different DSR does not have a configured valid PUCCH resource.

[0123] In step 502, when a random access procedure is in progress due to a pending SR for a DSR, the pending SR for the DSR does not have a configured valid PUCCH resource, and a new random access procedure is triggered due to a pending SR for a different DSR, the UE (100) continues the current random access procedure and does not initiate a new random access procedure. The pending SR for the different DSR is associated with an LCG / logical channel, which has a lower priority than the LCG / logical channel associated with the ongoing random access procedure, and the pending SR for the different DSR does not have a configured valid PUCCH resource.

[0124] In an embodiment, if a random access procedure is in progress due to a pending SR for a DSR, the pending SR for a DSR associated with the LCG / logical channel does not have a configured valid PUCCH resource, and a new random access procedure is triggered due to a pending SR for a different DSR, then the UE (100) continues the current random access procedure and does not initiate a new random access procedure, and the pending SR for a different DSR does not have a configured valid PUCCH resource.

[0125] In step 503, when no valid PUCCH resource is configured for the new SR, the UE (100) cancels the new SR for a different DSR on the same logical channel for the LCG. This ensures that the system does not waste resources trying to initiate a random access procedure that cannot be completed due to the lack of valid PUCCH resources.

[0126] In step 504, when a new SR for a different DSR does not have a configured valid PUCCH resource, a new random access procedure is not initiated while the previous random access procedure is already in progress. This step helps maintain network efficiency by preventing the initiation of potentially unsuccessful redundant procedures.

[0127] Figure 6 A flowchart (600) is shown of a method for transmission of a complete DSR MAC CE according to an embodiment disclosed herein.

[0128] In this embodiment, in step 601, the UE (100) detects the existence of at least one pending DSR and whether UL-SCH resources are available for a new transmission. In step 602, the UE (100) determines whether the available UL-SCH resources can fully accommodate the DSR MAC CE as a result of logical channel prioritization, plus its sub-header. In step 603, the MAC layer / entity (107) of the UE (100) instructs a multiplexing and assembly process to generate the DSR MAC CE. In step 604, when the delay information (remaining time field and buffer size field) of all pending DSRs in the corresponding logical channel group (LCG) can be accommodated in the DSR MAC CE, the UE (100) determines the complete DSR MAC CE. If the complete DSR MAC CE can be accommodated in the uplink resources, the UE (100) determines in step 605 whether there are any pending SRs that have been triggered by the DSR process for the same logical channel up to this DSR. In addition, in step 606, the MAC layer / entity (107) of the UE (100) triggers a scheduling request.

[0129] Example 3:

[0130] If there is at least one DSR to be processed, the MAC entity can:

[0131] 1> If the UL-SCH resource is available for a new transmission, and the UL-SCH resource can fully accommodate the DSR MAC CE as a result of logical channel prioritization, plus its sub-header:

[0132] 2> Instructions for reuse and assembly processes to generate DSR MAC CE;

[0133] 1> Otherwise, if there is no pending SR that has been triggered by the DSR procedure for the same logical channel up to this DSR:

[0134] 2> Trigger a scheduling request.

[0135] Figure 7 A flowchart (700) is shown of a method for transmission of a partial DSR MAC CE according to an embodiment disclosed herein.

[0136] In an embodiment, in step 701, the UE (100) detects whether there is at least one DSR pending processing and whether the UL-SCH resource is available for a new transmission. In step 702, the UE (100) determines whether the UL-SCH resource can fully accommodate the DSR MAC CE as a result of logical channel prioritization, plus its sub-header. If true, then in step 703, the MAC layer / entity (107) of the UE (100) instructs a multiplexing and assembly process to generate the DSR MAC CE, and in step 704, when the delay information of all LCGs with pending DSRs is contained within the DSR MAC CE, the UE (100) sends the complete DSR MAC CE plus its sub-header, wherein the delay information includes a remaining time field and a buffer size field.

[0137] If false, then in step 705, the UE (100) determines whether at least one DSR for an LCG can be contained in the UL-SCH resource along with the sub-header. In step 706, the MAC layer / entity (107) of the UE (100) instructs a multiplexing and assembly process to generate a DSR MAC CE, and in step 707, when the delay information (remaining time and buffer size fields) of at least one pending DSR of the corresponding LCG can be contained in the DSR MAC CE and the delay information (remaining time and buffer size fields) of at least one pending DSR of the corresponding LCG cannot be contained in the DSR MAC CE, the UE (100) sends a partial DSR MAC CE. In step 708, the UE (100) cancels the DSR contained in the DSR MAC CE. At step 709, the UE (100) determines that there is at least one pending DSR that has not yet been canceled.

[0138] In step 710, the UE (100) determines whether there is any pending SR that has been triggered by the DSR procedure for the same logical channel up to this DSR. In step 711, the MAC layer / entity (107) of the UE (100) triggers the SR.

[0139] Example 4:

[0140] If there is at least one DSR to be processed, the MAC entity can:

[0141] 1> If the UL-SCH resource is available for a new transmission, and the UL-SCH resource can accommodate a DSR MAC CE for at least one DSR for the LCG as a result of logical channel prioritization, plus its sub-header:

[0142] 2> Instructions for reuse and assembly processes to generate DSR MAC CE;

[0143] 1> If there is at least one pending DSR that has not yet been cancelled, and if, up to that DSR, there are no pending SRs that have been triggered by the DSR procedure for the same logical channel:

[0144] 2> Trigger a scheduling request.

[0145] In this embodiment, the UE (100) implements whether to instruct the multiplexing and assembly process to partially or fully generate the DSR MAC CE based on the availability of uplink resources. That is, the UE (100) implementation supports partial or complete DSR reporting. The UE (100) can implement UE (100) capabilities supporting partial DSR reporting through optional capabilities that do not signal to the network or optional or mandatory capabilities that signal to the network. Signaling can be carried in UE (100) capability information messages or associated with UE (100) capabilities supporting XR and / or DSR features.

[0146] In this embodiment, the MAC layer / entity (107) of the UE (100) triggers DSR for the LCG if the following conditions are met:

[0147] 1) The minimum remaining value of PDCP discardTimers becomes lower than the remainingTimeThreshold of LCG in all data buffered for LCG that has not yet been sent in any MAC PDU or reported as data volume in DSR MAC CE; and

[0148] 2) There are no pending DSRs for LCG since the last transmission of DSR MAC CE (including delay information for LCG).

[0149] Example 5:

[0150] If the LCG is configured for delay status reporting, the MAC entity can:

[0151] 1> If the minimum remaining value of PDCP discardTimers in all data buffered for LCG that has not yet been sent in any MAC PDU or reported as data volume in DSR MAC CE becomes lower than the remainingTimeThreshold of LCG; and

[0152] 2> Trigger DSR for LCG.

[0153] In an embodiment, if at least one DSR is pending and if UL-SCH resources are available for a new transmission, and the UL-SCH resources can partially or completely accommodate the DSR MAC CE as a result of logical channel prioritization, plus its sub-header, then the MAC layer / entity (107) of the UE (100) instructs a multiplexing and assembly process to generate the DSR MAC CE. A partial DSR MAC CE is determined when the delay information (remaining time field and buffer size field) of at least one pending DSR from the corresponding LCG can be accommodated in the DSR MAC CE, and the delay information of at least one pending DSR from the corresponding LCG cannot be accommodated in the DSR MAC CE. The DSR accommodated in the DSR MAC CE is then cancelled. In addition, if there is more than one pending DSR that has not yet been cancelled, the MAC layer / entity (107) of the UE (100) triggers a scheduling request, and the SR configuration of the logical channel is selected based on at least one of the following criteria: the logical channel (LCH) with the highest priority, the configured LCH, the LCH that triggered the first pending DSR, and the LCH with the lowest delay value.

[0154] In one embodiment, if at least one DSR is pending and if UL-SCH resources are available for a new transmission, and the UL-SCH resources cannot fully accommodate the DSR MAC CE and its sub-headers as a result of logical channel prioritization, the MAC layer / entity (107) of the UE (100) instructs a multiplexing and assembly process to generate a partial DSR MAC CE. The MAC layer / entity (107) considers the pending DSRs in descending order of priority levels of the LCG / LCH of the triggered DSRs for constructing the MAC CE, and constructs the partial DSR MAC CE accordingly. In another embodiment, the UL resource or license considered may be at least one of an uplink license received in the RAR, an uplink license determined for the transmission of the MSG1 payload, a configured uplink license, and a dynamic uplink license addressed to the C-RNTI.

[0155] Therefore, the solution disclosed above introduces an innovative approach to DSR processing tailored for XR applications. The solution aims to address the challenges associated with insufficient uplink resources and the need for efficient random access procedures, particularly when uplink clearance is unavailable to accommodate DSR MAC CE transmissions.

[0156] The technical advantage of this disclosure lies in its ability to implement an efficient method for latency status reporting for XR. This disclosure improves the performance of both the UE and the network system for XR applications. Reduced unnecessary signaling and optimized resource allocation result in a more responsive and reliable XR experience. This is particularly important in applications that prioritize low latency and high reliability, such as in VR, AR, and other immersive technologies.

[0157] Figure 8 The structure of a UE according to an embodiment of the present disclosure is shown.

[0158] like Figure 8 As shown, the UE according to the embodiment may include a transceiver 810, a memory 820, and a processor 830. The transceiver 810, memory 820, and processor 830 of the UE can operate according to the 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. Furthermore, the processor 830, transceiver 810, and memory 820 may be implemented as a single chip. In addition, the processor 830 may include at least one processor.

[0159] Transceiver 810 is collectively referred to as UE receiver and UE transmitter, and can transmit / receive signals to / from a base station. Signals transmitted to or received from the base station may include control information and data. Transceiver 810 may include an RF transmitter for up-converting and amplifying the frequency of the transmitted signal, and an RF receiver for low-noise amplification and down-converting the frequency of the received signal. However, this is only an example of transceiver 810, and the components of transceiver 810 are not limited to RF transmitters and RF receivers.

[0160] In addition, transceiver 810 can receive signals via a wireless channel and output them to processor 830, and can also transmit signals output from processor 830 via a wireless channel.

[0161] The memory 820 can store programs and data required for the operation of the UE. Furthermore, the memory 820 can store control information or data included in signals received by the UE. The memory 820 can be a storage medium such as read-only memory (ROM), random access memory (RAM), hard disk, CD-ROM, and DVD, or a combination of storage media.

[0162] The processor 830 can control a series of processes to enable the UE to operate as described above. For example, the transceiver 810 can receive data signals including control signals transmitted by the base station, and the processor 830 can determine the result of receiving the control signals and data signals transmitted by the base station.

[0163] Figure 9 The structure of a base station according to an embodiment of the present disclosure is shown.

[0164] like Figure 9 As shown, a base station according to an embodiment may include a transceiver 910, a memory 920, and a processor 930. The transceiver 910, memory 920, and processor 930 of the base station can operate according to the 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. Furthermore, the processor 930, transceiver 910, and memory 920 may be implemented as a single chip. In addition, the processor 930 may include at least one processor.

[0165] Transceiver 910 is collectively referred to as a base station receiver and a base station transmitter, and can transmit signals to / receive signals from a terminal. Signals transmitted to or received from a terminal may include control information and data. Transceiver 910 may include an RF transmitter for up-converting and amplifying the frequency of the transmitted signal, and an RF receiver for low-noise amplification and down-converting the frequency of the received signal. However, this is only an example of transceiver 910, and the components of transceiver 910 are not limited to RF transmitters and RF receivers.

[0166] In addition, transceiver 910 can receive signals via a wireless channel and output them to processor 930, and can also transmit signals output from processor 930 via a wireless channel.

[0167] The memory 920 can store programs and data required for the operation of the base station. Furthermore, the memory 920 can store control information or data included in signals acquired by the base station. The memory 920 can be a storage medium such as a read-only memory (ROM), random access memory (RAM), hard disk, CD-ROM, and DVD, or a combination of storage media.

[0168] The processor 930 can control a series of processes to enable the base station to operate as described above. For example, the transceiver 910 can receive data signals including control signals transmitted by the terminal, and the processor 930 can determine the result of receiving the control signals and data signals transmitted by the terminal.

[0169] The description of the specific embodiments above will fully reveal the general nature of the embodiments herein. Others can readily modify and / or adapt these specific embodiments for various applications by applying existing knowledge without departing from the general concepts. Therefore, such modifications and adaptations should and are intended to be understood as equivalents of the disclosed embodiments. It should be understood that the wording or terminology used herein is for descriptive purposes and not for limitation. Therefore, although the embodiments herein have been described according to preferred embodiments, those skilled in the art will recognize that the embodiments herein can be practiced with modifications within the scope of the embodiments described herein.

[0170] Although this disclosure has been described with reference to various embodiments, various changes and modifications may be suggested to those skilled in the art. This disclosure is intended to cover such changes and modifications that fall within the scope of the appended claims.

Claims

1. A user equipment (UE) in a wireless communication system, the UE comprising: transceiver; and A controller, coupled to the transceiver and configured to: If there is no pending scheduling request (SR) already triggered by the Delay Status Report (DSR) procedure for the same logical channel associated with the DSR procedure, trigger the SR for the DSR. Identify that the SR for the DSR does not have a valid Physical Uplink Control Channel (PUCCH) resource configured. Perform the random access procedure, and Cancel the SR for the DSR.

2. The UE according to claim 1, wherein, The SR is cancelled if the SR for the DSR is triggered by the DSR process and the DSR process is cancelled.

3. The UE according to claim 1, wherein, The controller is also configured to: The random access procedure is terminated because the SR for the DSR is not configured with a valid PUCCH resource.

4. The UE according to claim 3, wherein, The random access procedure is stopped when all Service Data Units (SDUs) associated with the DSR have been discarded.

5. The UE according to claim 3, wherein, The random access procedure is stopped if a Media Access Control (MAC) Protocol Data Unit (PDU) is sent with a UL permission other than the uplink (UL) permission provided by the random access response or the UL permission determined for the transmission of the message A (MSGA) payload.

6. The UE according to claim 5, wherein, The MAC PDU includes the DSR MAC control element (CE) and one of all SDUs associated with the DSR.

7. The UE according to claim 1, in, The controller is also configured to perform a multiplexing and reassembly process to generate the DSR MAC CE when UL shared channel (SCH) resources are available for new transmissions and the UL-SCH resources are capable of accommodating the DSR MAC CE plus its sub-header as a result of logical channel prioritization. The DSR MAC CE includes delay information for all logical channel groups (LCGs) corresponding to the DSR to be processed.

8. A method performed by a user equipment (UE) in a wireless communication system, the method comprising: If there is no pending scheduling request (SR) that has been triggered by the Delay Status Report (DSR) procedure for the same logical channel associated with the DSR procedure, trigger the SR for the DSR. Identify that the SR for the DSR does not have a valid Physical Uplink Control Channel (PUCCH) resource configured; Perform the random access procedure; and Cancel the SR for the DSR.

9. The UE according to claim 8, wherein, The SR is cancelled if the SR for the DSR is triggered by the DSR process and the DSR process is cancelled.

10. The UE according to claim 8, further comprising: The random access procedure is terminated because the SR for the DSR is not configured with a valid PUCCH resource.

11. The UE according to claim 10, wherein, The random access procedure is stopped when all Service Data Units (SDUs) associated with the DSR have been discarded.

12. The UE according to claim 10, wherein, The random access procedure is stopped if a Media Access Control (MAC) Protocol Data Unit (PDU) is sent with a UL permission other than the uplink (UL) permission provided by the random access response or the UL permission determined for the transmission of the message A (MSGA) payload.

13. The UE according to claim 12, wherein, The MAC PDU includes the DSR MAC control element (CE) and one of all SDUs associated with the DSR.

14. The UE according to claim 8, further comprising: If the UL shared channel (SCH) resources are available for a new transmission and the UL-SCH resources are sufficient to accommodate the DSR MAC CE as a result of logical channel prioritization, along with its sub-header, a multiplexing and reassembly process is performed to generate the DSR MAC CE. The DSR MAC CE includes delay information for all logical channel groups (LCGs) corresponding to the DSR to be processed.

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