WO2025030466A1

WO2025030466A1 - Wireless communication method and device

Info

Publication number: WO2025030466A1
Application number: PCT/CN2023/112166
Authority: WO
Inventors: Yincheng Zhang; Liping Wang
Original assignee: Shenzhen TCL New Technology Co Ltd
Current assignee: Shenzhen TCL New Technology Co Ltd
Priority date: 2023-08-10
Filing date: 2023-08-10
Publication date: 2025-02-13
Anticipated expiration: 2026-02-10
Also published as: CN121666838A

Abstract

A wireless communication method for wireless communication device. A protocol layer in a transmitter device receives multiple service data units (SDUs) for synchronous transfer and synchronous transfer indication information from an upper protocol layer. The protocol layer encapsulates the multiple SDUs into one or more protocol data units (PDUs) in the protocol layer for synchronous transfer based on the synchronous transfer indication information. The protocol layer provides the one or more PDUs to a lower protocol layer for synchronous transfer.

Description

WIRELESS COMMUNICATION METHOD AND DEVICE

BACKGROUND OF DISCLOSURE

1. Field of Disclosure

The present disclosure relates to the field of telecommunication, and in particular to a wireless communication method and device.

2. Description of Related Art

The 5G wireless communication system has been designed to deliver legacy services, such as enhanced mobile broadband (eMBB) , ultra-reliable low-latency communication (URLLC) , and massive machine type communication (mMTC) services. In 5G or NR, features supporting eMBB, URLLC, and mMTC was introduced in Release 15 and enhanced in Release 16 and 17.

Tactile and multi-modal communication services facilitate multi-modal interactions that combine ultra-low latency with high levels of availability, reliability and security. These services have potential applications in various domains, such as industry, robotics and telepresence, virtual reality, augmented reality, healthcare, road traffic, gaming, education, culture and smart grid. These services enable applications that use input from multiple sources and/or output to multiple destinations to convey information more effectively. The input and output can involve different modalities, such as:

- Video/Audio media;

- Environmental sensor data, such as brightness, temperature, humidity, etc. ; and/or

- Haptic data: including tactile sensations (e.g., pressure, texture, vibration, temperature) and kinesthetic senses (e.g., gravity, pull forces, sense of position awareness) .

Immersive multi-modal VR applications require strict synchronization among different media components to avoid degrading the user experience (e.g., viewers noticing asynchrony) .

Technical Problem

In essence, a multi-modal service typically involves multiple Quality of Service (QoS) flows and multiple Data Radio Bearers (DRBs) or Logical Channel Groups (LCHs) derived from these QoS flows. The synchronization requirement can be applicable to multiple Service Data Units (SDUs) /Protocol Data Units (PDUs) for a single DRB/LCH or across multiple DRB/LCHs. The current design of NR (New Radio) Layer 2 structure and data flow are not designed for synchronous transfer. The primary concern is how to enhance the foundational principles of Layer 2 structure and data flow to meet the synchronization requirements of a multi-modal service.

Several other issues related to synchronous transfer are as follows:

Configuration of synchronous transfer: This involves determining the appropriate settings and parameters for achieving synchronization between the involved components.

gNB awareness of the multi-modal service from the UE: It is essential to establish a mechanism through which the gNB can recognize and comprehend the multi-modal service requirements originating from the User Equipment (UE) .

Handling out-of-synchronized SDU/PDU (s) and discarding SDU/PDU (s) for congestion: Strategies must be devised to address situations where SDUs/PDUs become out of sync or need to be discarded due to congestion issues.

Hence, a wireless communication method that provides an enhancement for synchronous transfer of multi-modal service is desired.

SUMMARY

An object of the present disclosure is to propose a UE and a wireless communication method and device.

In a first aspect, an embodiment of the invention provides a wireless communication method for wireless communication device, comprising: receiving multiple service data units (SDUs) for synchronous transfer and synchronous transfer indication information from an upper protocol layer; encapsulating the multiple SDUs into one or more protocol data units (PDUs) in a protocol layer for synchronous transfer based on the synchronous transfer indication information; and providing the one or more PDUs to a lower protocol layer for synchronous transfer.

In a second aspect, an embodiment of the invention provides a wireless communication device operating as a transmitter comprising a processor configured to call and run a computer program stored in a memory, to cause a device in which the processor is installed to execute the disclosed method.

In a third aspect, an embodiment of the invention provides a wireless communication method for wireless communication device, comprising:

receiving one or more protocol data units (PDUs) for synchronous transfer from a lower protocol layer; decapsulating the one or more PDUs into multiple service data units (SDUs) in a protocol layer for synchronous transfer based on configuration information for synchronous transfer and/or a PDU format of the PDUs for synchronous transfer; and

providing the multiple SDUs to an upper protocol layer for synchronous transfer.

In a fourth aspect, an embodiment of the invention provides a wireless communication device operating as a receiver comprising a processor configured to call and run a computer program stored in a memory, to cause a device in which the processor is installed to execute the disclosed method.

The disclosed method may be implemented in a chip. The chip may include a processor, configured to call and run a computer program stored in a memory, to cause a device in which the chip is installed to execute the disclosed method.

The disclosed method may be programmed as computer executable instructions stored in non-transitory computer readable medium. The non-transitory computer readable medium, when loaded to a computer, directs a processor of the computer to execute the disclosed method.

The non-transitory computer readable medium may comprise at least one from a group consisting of: a hard disk, a CD-ROM, an optical storage device, a magnetic storage device, a Read-Only Memory, a Programmable Read-Only Memory, an Erasable Programmable Read-Only Memory, EPROM, an Electrically Erasable Programmable Read-Only Memory and a Flash memory.

The disclosed method may be programmed as a computer program product, which causes a computer to execute the disclosed method.

The disclosed method may be programmed as a computer program, which causes a computer to execute the disclosed method.

Advantageous Effects

In the description, synchronization information is provided for multi-modal service. Synchronization information is a crucial aspect of ensuring quality of service and user satisfaction. Multi-modal service refers to the delivery of content or functionality through different modes or channels, such as audio, video, text, graphics, etc. Synchronization information specifies the temporal relationships between the different modes, such as when to start, stop, pause, resume, or switch between them. Without proper synchronization information, the multi-modal service may suffer from delays, inconsistencies, errors, or interruptions, which can negatively affect the user experience and the performance of the service. Therefore, providing synchronization information for multi-modal service can have several technical effects, such as:

- Improving the accuracy and reliability of the multi-modal service by ensuring that the different data flows are aligned and coordinated according to the intended design and logic.

- Enhancing the efficiency and scalability of the multi-modal service by reducing the bandwidth and processing requirements for transmitting and processing the different modes.

- Increasing the flexibility and adaptability of the multi-modal service by enabling dynamic and seamless switching between different modes focusing on different media components according to the user preferences, context, or device capabilities.

- Supporting the accessibility and usability of the multi-modal service by facilitating the integration of alternative or complementary media components for users with different needs, preferences, or abilities.

BRIEF DESCRIPTION OF DRAWINGS

In order to more clearly illustrate the embodiments of the present disclosure or related art, the following figures will be described in the embodiments are briefly introduced. It is obvious that the drawings are merely some embodiments of the present disclosure, a person having ordinary skill in this field can obtain other figures according to these figures without paying the premise.

FIG. 1 illustrates a schematic view showing a system comprising a core network, a RAN, and user equipments (UEs) .

FIG. 2 illustrates a schematic view showing a data network and an application server.

FIG. 3 illustrates a schematic view showing protocol layers of a transmitter and a receiver device.

FIG. 4 illustrates a schematic view showing a downlink layer 2 structure.

FIG. 5 illustrates a schematic view showing an uplink layer 2 structure.

FIG. 6 illustrates a schematic view showing layer 2 data flows.

FIG. 7 illustrates a schematic view showing an embodiment of the disclosed wireless communication method in a protocol layer of a transmitter device.

FIG. 8 illustrates a schematic view showing an embodiment of the disclosed wireless communication method in a protocol layer of a receiver device.

FIG. 9 illustrates a schematic view showing an example of a SDAP Data PDU format without SDAP header.

FIG. 10 illustrates a schematic view showing an example of a SDAP Data PDU format with SDAP header.

FIG. 11 illustrates a schematic view showing an example of UL SDAP Data PDU format with SDAP header.

FIG. 12 illustrates a schematic view showing an of PDCP Data PDU format with 12 bits PDCP SN.

FIG. 13 illustrates a schematic view showing an example of PDCP Data PDU format for DRBs with 18 bits PDCP SN.

FIG. 14 illustrates a schematic view showing an example of PDCP Data PDU format with 12 bits PDCP SN.

FIG. 15 illustrates a schematic view showing an example of PDCP Data PDU format for DRBs with 18 bits PDCP SN.

FIG. 16 illustrates a schematic view showing an example of TMD PDU.

FIG. 17 illustrates a schematic view showing an example of UMD PDU containing more than one complete RLC SDUs.

FIG. 18 illustrates a schematic view showing an example of UMD PDU with 6-bit SN and without SO.

FIG. 19 illustrates a schematic view showing an example of UMD PDU with 6-bit SN and with SO.

FIG. 20 illustrates a schematic view showing an example of AMD PDU with 12-bit SN (No SO) .

FIG. 21 illustrates a schematic view showing an example of AMD PDU with 12-bit SN with SO.

FIG. 22 illustrates a schematic view showing an example of data packets of these three QoS flows with different periodicities.

FIG. 23 illustrates a schematic view showing an example of BSR MAC CE.

FIG. 24 illustrates a schematic view showing an example of data packets of these three QoS flows with different periodicities.

FIG. 25 illustrates a schematic view showing an example of a LCG with arrival time difference between PDU sets of different LCHs.

FIG. 26 illustrates a schematic view showing an example of BSR for status information of out-of-synchronization.

FIG. 27 illustrates a schematic view showing an example of BSR for status information of out-of-synchronization.

FIG. 28 illustrates a schematic view showing a system for wireless communication according to an embodiment of the present disclosure.

DETAILED DESCRIPTION OF EMBODIMENTS

Embodiments of the disclosure are described in detail with the technical matters, structural features, achieved objects, and effects with reference to the accompanying drawings as follows. Specifically, the terminologies in the embodiments of the present disclosure are merely for describing the purpose of the certain embodiment, but not to limit the disclosure.

Abbreviations used in the description are listed in the following:

Table 1

This invention disclosed a wireless communication method for processing synchronous transfer for multi-modal service (s) .

In the description, packets, protocol data unit (PDU) , and/or PDU sets of a service are referred to as traffic data for simplicity.

In the description, a packet may be a PDU or a SDU of a protocol layer. For simplicity, the term packet may refer to a PDU or SDU, and the term PDU may refer to a PDU or SDU. In the description, the term “resource” comprises radio resources in time and frequency domains.

A UE may transmit a buffer status report (BSR) to a gNB. The Buffer Status reporting (BSR) procedure is used to provide the serving gNB with information about uplink (UL) data volume in the MAC entity of the UE.

With reference to FIG. 1, a telecommunication system including a UE 10a, a UE 10b, a base station (BS) 20a, and a network entity device 30 executes the disclosed method according to an embodiment of the present disclosure. FIG. 1 is shown for illustrative, not limiting, and the system may comprise more UEs, BSs, and CN entities. Connections between devices and device components are shown as lines and arrows in the FIGs. The UE 10a may include a processor 11a, a memory 12a, and a transceiver 13a. The UE 10b may include a processor 11b, a memory 12b, and a transceiver 13b. The base station 20a may include a processor 21a, a memory 22a, and a transceiver 23a. The network entity device 30 may include a processor 31, a memory 32, and a transceiver 33. Each of the processors 11a, 11b, 21a, and 31 may be configured to implement proposed functions, procedures and/or methods described in the description. Layers of radio interface protocol may be implemented in the processors 11a, 11b, 21a, and 31. Each of the memory 12a, 12b, 22a, and 32 operatively stores a variety of programs and information to operate a connected processor. Each of the transceivers 13a, 13b, 23a, and 33 is operatively coupled with a connected processor, transmits and/or receives radio signals or wireline signals. The UE 10a may be in communication with the UE 10b through a sidelink. The base station 20a may be an eNB, a gNB, or one of other types of radio nodes, and may configure radio resources for the UE 10a and UE 10b.

The network entity device 30 may be a node in a CN. CN may include LTE CN or 5G core (5GC) which includes user plane function (UPF) , session management function (SMF) , 5G core access and mobility management function (AMF) , unified data management (UDM) , policy control function (PCF) , control plane (CP) /user plane (UP) separation (CUPS) , authentication server (AUSF) , network slice selection function (NSSF) , and the network exposure function (NEF) .

An example of the UE in the description may include one of the UE 10a or UE 10b. An example of the base station in the description may include the base station 20a. Uplink (UL) transmission of a control signal or data may be a transmission operation from a UE to a base station. Downlink (DL) transmission of a control signal or data may be a transmission operation from a base station to a UE. A DL control signal may comprise downlink control information (DCI) or a radio resource control (RRC) signal, from a base station to a UE.

FIG. 2 is a model of a transport network for multi-modal service supported by 5G system. A UE 10 is a 5G terminal which can support multi-modal service and service-related application and can be referred to as a client, a client terminal, or a service client. A gNB 20 is 5G radio node. The gNB 20 communicates with the UE 10 and provides NR user plane and control plane protocol terminations towards the UE via NR Uu interface. The gNB 20 connects via NG interface to a 5GC 300. An UPF 30b is an UPF in the 5GC 300 which is a 5G Core Network. DN 40 is a data network (DN) 40 where an application server 41 providing multi-modal service is located. The DN 40 can provide network operator services, Internet access, or 3rd party services. The application server 41 may include a processor 411, a memory 412, and a transceiver 413. The processor 411 may be configured to implement multi-modal service-related functions, procedures and/or methods described in the description. Layers of radio interface protocol may be implemented in the processor 411. The memory 412 operatively stores a variety of programs and information to operate a connected processor. The transceiver 413 is operatively coupled with a connected processor, transmits and/or receives radio signals or wireline signals.

Each of the processors 411, 11a, 11b, 21a, and 31 may include an application-specific integrated circuit (ASICs) , other chipsets, logic circuits and/or data processing devices. Each of the memory 412, 12a, 12b, 22a, and 32 may include read-only memory (ROM) , a random-access memory (RAM) , a flash memory, a memory card, a storage medium and/or other storage devices. Each of the transceivers 413, 13a, 13b, 23a, and 33 may include baseband circuitry and radio frequency (RF) circuitry to process radio frequency signals. When the embodiments are implemented in software, the techniques described herein may be implemented with modules, procedures, functions, entities, and so on, that perform the functions described herein. The modules may be stored in a memory and executed by the processors. The memory may be implemented within a processor or external to the processor, in which those may be communicatively coupled to the processor via various means are known in the art. FIG. 1 provides examples of UE, gNB, base station, CN, core network entities mentioned in the description.

A device executing the wireless communication method may be a transmitter device that transmits a service traffic flow of a multi-modal service to a receiver device or a receiver device that receives the service traffic flow. The service traffic flow may comprise one or more service traffic streams of the multi-modal service. For example, the device executing the wireless communication method may comprise the gNB 20, an application server 41 in data network 40, or a UE. That is, the application server 41 in data network 40 may operate as a transmitter device that executes a wireless communication method in some service traffic delivery occasions, while one or more service clients (e.g., one or more of the UE 10, UE 10a, and UE 10b) operates as the receiver device receiving the service traffic flow sent from the transmitter device. Similarly, a service client (e.g., one or more of the UE 10, UE 10a, and UE 10b) may operate as a transmitter device to execute a wireless communication method in some service traffic delivery occasions, while another service client or the application server 41 operates as the receiver device receiving the service traffic flow sent from the transmitter device. Alternatively, the transmitter device may comprise an intermediate device between the UE 10 and the application server 41. The UE 10 may comprise an embodiment of the UE 10a or UE 10b. The gNB 20 may comprise an embodiment of the base station 20a. Note that although the gNB 20 and UPF 30b are described as an example in the description, the wireless communication method may be executed by a base station, such as another gNB, an eNB, a base station integrating an eNB and a gNB, or a base station for beyond 5G technologies. The UPF 30b may comprise another network entity of 5GC.

A service traffic stream 5, such as a service stream of a multi-modal service, is established between the UE 10 and the application server 41. The stream 5 comprises a traffic flow 51 from the application server 41 to the UE 10 and a traffic flow 52 from the UE 10 to the application server 41.

In the description, a layer, such as an application layer, a SDAP, a PDCP layer, an RLC layer, an MAC layer, or a physical layer (PHY layer or L1 layer) , may be a protocol layer entity in a transmitter device or a receiver device. A protocol layer entity may be implemented by a program or a software module executed by a processor, a hardware module in an integrated circuit (IC) , or a combination thereof.

With reference to FIG. 3, an example of the transmitter device is shown as transmitter device 10c, and an example of the receiver device is shown as receiver device 10d. The transmitter device 10c comprises a user plane protocol stack and a control plane protocol stack. The control plane comprises a physical layer (PHY layer or L1 layer) 14c, MAC layer 15c, RLC layer 16c, PDCP layer 17c, RRC layer 18-1c, and NAS layer 19-1c. The user plane comprises a physical layer (PHY layer or L1 layer) 14c, MAC layer 15c, RLC layer 16c, PDCP layer 17c, SDAP layer 18-2c, IP layer 19-2c, and application layer 19-3c.

The receiver device 10d comprises a user plane protocol stack and a control plane protocol stack. The control plane comprises a physical layer (PHY layer or L1 layer) 14d, MAC layer 15d, RLC layer 16d, PDCP layer 17d, RRC layer 18-1d, and NAS layer 19-1c. The user plane comprises a physical layer (PHY layer or L1 layer) 14d, MAC layer 15d, RLC layer 16d, PDCP layer 17d, SDAP layer 18-2d, IP layer 19-2d, and application layer 19-3d.

For example, when the application layer 19-3c of the transmitter device 10c sends a PDU through lower layers (i.e., IP layer 19-2c, SDAP layer 18-2c, PDCP layer 17c, RLC layer 16c, MAC layer 15c, and physical layer 14c) to the application layer 19-3d of the receiver device 10d, the layers in transmitter device 10c serves as transmitting protocol layer entities at the transmitting side, and the layers in receiver device 10d serve as receiving protocol layer entities at the receiving side. Embodiments of the disclosed may be implemented in the SDAP layer, PDCP layer, RLC layer, or MAC layer. One or more steps (or blocks) in of embodiments of the disclosure may be implemented as computer programs, instructions, software module (s) stored in a memory of the transmitter device, or circuits or hardware module (s) in a processor of the transmitter device, or IC chip (s) , circuits, or plug-in (s) of the transmitter device. Layer entities here provides examples of layers mentioned in the description.

The layers in the FIG. 3 may conform to NR (New Radio) radio communication system, as defined by the 3GPP standards, which can be represented by FIG. 4 to FIG. 6. Examples of layers in FIG. 4 to FIG. 6 may comprise protocol layer entities in FIG. 3. In FIG. 4, examples of UE₁ to UE_n may comprise UEs in FIG. 1. The figures illustrate the main components and functions of layer 2, as well as the interfaces and protocols that enable data transmission and reception. The following paragraphs provide a brief overview of each sublayer and its role in the NR system.

With reference to FIGs. 7 and 8, a protocol layer (e.g., MAC layer 15c, RLC layer 16c, PDCP layer 17c, SDAP layer 18-2c) of the transmitter device (as shown in FIG. 3) and a protocol layer (e.g., MAC layer 15d, RLC layer 16d, PDCP layer 17d, SDAP layer 18-2d) of the receiver device (as shown in FIG. 3) execute the disclosed method for a multi-modal service.

The protocol layer of the transmitter device receives multiple service data units (SDUs) for synchronous transfer and synchronous transfer indication information from an upper protocol layer (A101) .

The protocol layer of the transmitter device encapsulates the multiple SDUs into one or more protocol data units (PDUs) in the protocol layer for synchronous transfer based on the synchronous transfer indication information (A102) . In some embodiments of the disclosure, when concatenation of the multiple SDUs does not exceed the maximum payload size of one PDU of the protocol layer, the multiple SDUs are encapsulated into one PDU of the protocol layer in an enhanced PDU format. When concatenation of the multiple SDUs exceeds the maximum payload size of one PDU of the protocol layer, the multiple SDUs are encapsulated into multiple PDUs of the protocol layer in the enhanced PDU format. In an embodiment of the invention, the enhanced PDU format is enabled based on a set of enhanced PDU formats supported by a user equipment (UE) in a UE capability report and a set of enhanced PDU formats supported by a base station in a broadcast or unicast downlink indication message.

The protocol layer of the transmitter device provides the one or more PDUs to a lower protocol layer for synchronous transfer (A103) .

Whether one PDU includes multiples SDUs for synchronous transfer may be indicated in a control plane scheme or a user plane scheme. In an embodiment of the invention, a control plane signal is transmitted to indicates whether the PDU format includes multiple SDUs for synchronous transfer. In an embodiment of the invention, a field in the enhance PDU format of the one or more PDUs indicates whether the PDU format includes multiple SDUs for synchronous transfer.

The protocol layer of the receiver device receives one or more protocol data units (PDUs) for synchronous transfer from a lower protocol layer (B101) .

The protocol layer of the receiver device decapsulates the one or more PDUs into multiple service data units (SDUs) in a protocol layer for synchronous transfer based on configuration information for synchronous transfer and/or the PDU format of the PDUs for synchronous transfer (B102) .

The protocol layer of the receiver device provides the multiple SDUs to an upper protocol layer for synchronous transfer (B103) .

In an embodiment of the invention, in a transmitter device, the multiple SDUs are encapsulated into one or more PDUs for synchronous transfer based on synchronous transfer indication information when an enhanced encapsulation function is enabled. In the transmitter device, the encapsulating the multiple SDUs into one or more PDUs for synchronous transfer based on synchronous transfer indication information is performed when an enhanced encapsulation function is enabled according to configuration information. In a receiver device, the multiple SDUs are decapsulated from one or more PDUs for synchronous transfer based on the enhanced PDU format when an enhanced encapsulation function is enabled according to the configuration information. The configuration information is conveyed in a radio resource control (RRC) message. In another example, the configuration information includes a control plane signal and conveyed in a radio resource control (RRC) message, wherein a control plane signal is transmitted to indicates whether the PDU formats supporting multiple SDUs are used for synchronous transfer. The configuration information is configured for the UE and is also used for packet decapsulation, such as in step B102.

In an embodiment of the invention, the protocol layer is a service data adaption protocol (SDAP) ; the configuration information of the enhanced encapsulation function comprises one or more instances of following information:

one or more quality of service (QoS) flow identification (s) of QoS flows associated with the SDUs for synchronous transfer; and

the configuration information for synchronous transfer requirement which at least includes a delay threshold between QoS flows.

In an embodiment of the invention, the protocol layer is a packet data convergence protocol (PDCP) layer. Relevant configuration information of the enhanced encapsulation function comprises a configuration for enabling the enhanced encapsulation function.

In an embodiment of the invention, the protocol layer is a radio link control (RLC) layer. Relevant configuration information of the enhanced encapsulation function comprises a configuration for enabling the enhanced encapsulation function.

In an embodiment of the invention, the protocol layer is a medium access control (MAC) layer. The configuration information of the enhanced encapsulation function further comprises one or more of:

● a data radio bearer (DRB) group or multiple DRB configured to establish synchronization relationships between DRBs for synchronous transfer;

● a logical channel group (LCG) which comprises the logical channels (LCHs) corresponding to the DRBs/QoS flows for synchronous transfer. The LCG is configured to establish synchronization relationships between the logical channels; and

● the configuration information about a delay threshold between QoS flows for synchronous transfer.

In an embodiment of the invention, configuration information for the synchronous DRB group or multiple DRB includes one or more of the following:

● a DRB group ID of the synchronous DRB group;

● DRB IDs of the member DRBs in the synchronous DRB group or multiple DRB; and

● primary DRB information which comprises a primary DRB ID and timing information of a primary DRB in the synchronous DRB group.

In an embodiment of the invention, the timing information comprise one or more of periodicity, jitter and data arrival time for the data corresponding to the primary DRB of the primary QoS flow.

In an embodiment of the invention, Radio resource scheduling for SDUs of the primary DRB is prioritized over radio resource scheduling for SDUs of the member DRBs.

In an embodiment of the invention, configuration information for the LCG includes one or more of the following:

● a synchronous LCG ID of the LCG;

● LCH IDs of member LCHs in the LCG;

● primary LCH information which comprises a primary LCH ID and timing information of a primary LCH in the LCG.

In an embodiment of the invention, the timing information comprise one or more of periodicity, jitter, and data arrival time for the data corresponding to the primary QoS flow.

In an embodiment of the invention, for synchronous uplink transmission scheduling, the MAC layer performs buffer size reporting (BSR) using a buffer size report (BSR) based on one or more instances of the following information:

● a LCG ID;

● one or more buffer size (s) according to one or more time ranges based on periodicity of one QoS flow/DRB data packets;

● one or more buffer size (s) for the buffered data complied with the configuration information for synchronous transfer requirement;

● one or more synchronization status information between different QoS flows, which comprises an out-of-synchronization indication which indicates whether data from a DRB/QoS flow is in synchronization or not relative to the data from the primary DRB/QoS flow; and a Differ time which is a data arrival time difference between a QoS flow and the primary DRB/QoS flow.

In an embodiment of the invention, the MAC layer performs out-of-synchronization event detection based on the synchronous transfer indication information and triggers reporting of an out-of-synchronization event or a BSR for out-of-synchronization event reporting when detecting the out-of-synchronization event or when a number of out-of-synchronization events occurring within a predefined or configured time range exceeds a predefined or configured threshold or when a ratio of out-of-synchronization SDUs to synchronized SDUs exceeds a pre-defined or configured threshold.

In an embodiment of the invention, the BSR for out-of-synchronization event reporting comprises for each LCG in the BSR one or more of: one indicator that indicate whether an out-of-synchronization event occurs in the LCG;

● a difference between arrival times of two or more SDUs of different streams of a service in the out-of-synchronization event; and

● a ratio of out-of-synchronization SDUs to synchronized SDUs, or a total number of SDUs within a pre-defined or configured time range.

Embodiment 1: SDAP MULTIPLEXING

For the cases where multiple streams of a service, such as XR service, are mapped onto one or more QoS flows and configured with synchronous transfer requirements, a transmitting application layer entity (i.e., an application layer entity in the transmitter device) corresponding to the service identifies multiple PDUs which need to be transferred synchronously from one or more QoS flows based on synchronous transfer indication information carried along with the PDUs. For example, multiple PDUs of the same PDU Set from the same QoS flow can be transferred synchronously. For multiple PDUs from multiple QoS flows, synchronous transfer indication information carried along with the PDUs can be a set or a certain range of timestamp, sequence number (SN) , or synchronization sequence number (SSN) information associated with the SDUs for synchronous transfer. The range can be predefined or configurable. Then, the application PDU and synchronous transfer indication information are received by the lower-layer SDAP entity together.

For example, in uplink transmission of the streams, the PDUs and synchronous transfer indication information may be provided by a transmitting application layer entity of a UE to an SDAP entity of the UE.

For example, in downlink transmission of the streams, the PDUs and synchronous transfer indication information may be provided by a transmitting application layer entity to a UPF in a CN, and then transferred to an SDAP entity of a gNB. The transmitting application layer entity may be an application layer entity in a transmitter device of the service.

As illustrated in FIG. 4 and FIG. 5, for the cases where one or more QoS flows are mapped onto one DRB and configured with synchronous transfer requirements, the transmitting SDAP entity corresponding to the DRB can multiplex the SDUs that need synchronous transfer into one PDU, such as multiplexing multiple SDUs of a PDU Set of a QoS flow, or multiplexing multiple SDUs from two or more QoS flows. The multiplexing multiple SDUs into one PDU is defined as enhanced encapsulation function which is applicable for all the following embodiments.

When the SDAP entity needs to support enhanced encapsulation function, it is necessary to configure the relevant information for the enhanced encapsulation function to the transmitting and receiving SDAP entities. Specifically, for the UE side, the gNB can configure the relevant information for the enhanced encapsulation function to the transmitting and receiving SDAP entity through a downlink control signal, such as a RRC message. As an example, based on the existing standard SDAP configuration information element (IE) , some configuration information for the enhanced encapsulation function is introduced. The required configuration information includes one or more of the following information:

● The configuration information to enable enhanced encapsulation function for synchronous transfer for uplink and/or downlink; and

● The QoS flow identification of QoS flows and relevant information for enhanced encapsulation function for synchronization transmission on uplink and/or downlink. Among the QoS flows, one of the QoS flows is a primary QoS flow that carries a media component of a multi-modal service, such as XR service, and is used as a reference for other QoS flows that carries media components of the multi-modal service for the synchronous operation, such as synchronization configuration, synchronization detection, and synchronous transfer.

For the SDAP entity configured with enhanced encapsulation function for synchronous transfer, the transmitting and receiving SDAP entities (i.e., the SDAP layer entity in the transmitter device and the SDAP layer entity in the receiver device) can use one or more enhanced SDAP PDU formats to support the SDU multiplexing based on current SDAP PDU formats. With reference to FIG. 9, FIG. 10, and FIG. 11, some examples of the enhanced SDAP PDU formats are provided based on that in current technical specification TS 37.324 of 3GPP.

Fields in the PDU formats are detailed in the following:

L: ALength field indicates the length of the corresponding SDAP SDU in bytes.

E: An Extension field is a flag indicating if the corresponding SDAP SDU is the last SDAP SDU or not in the SDAP PDU. The E field is set to "1" to indicate at least another SDAP PDU follows. The E field is set to "0" to indicate that the SDAP PDU is the last one;

The other field is the same as that in current technical specification TS 37.324 of 3GPP.

For the transmitting SDAP entity, which is configured and enabled with enhanced encapsulation function, the SDAP entity may identify more than one SDUs which need to be transferred synchronously from one or more QoS flows first. For example, multiple SDUs of the same PDU Set from the same QoS flow can be transferred synchronously. For multiple SDUs from multiple QoS flows, synchronous transfer indication information carried along with the SDUs can be used to identify the synchronous transfer requirements. For example, the synchronous transfer indication information may comprise a set or a certain range of timestamp, sequence number (SN) , or synchronization sequence number (SSN) information associated with the SDUs for synchronous transfer. The range can be predefined or configurable. The transmitting SDAP entity multiplex the multiple SDUs into one SDAP PDU and send it to the lower protocol entity.

Further, if the length of two or more SDUs concatenated into SDAP PDU is longer than the limitation of the maximum size of a single SDAP PDU, the transmitting SDAP entity can encapsulate the multiple SDUs into multiple SDAP PDUs.

At the receiving SDAP entity, based on the relevant configuration for enhanced encapsulation function, the SDAP PDUs are decapsulated into one or multiple SDUs according to the SDAP PDU format, and the receiving SDAP entity sends them to the upper protocol entity (e.g., the application layer) in the form of QoS flows. Decapsulation may include header removing and a reversion operation of SDU concatenation.

Embodiment 2: PDCP MULTIPLEXING

For the cases where one or more QoS flows are mapped onto one DRB and configured with synchronous transfer requirements, the transmitting SDAP entity corresponding to the DRB identifies multiple SDUs which need to be transferred synchronously from one or more QoS flows based on the synchronous transfer indication information carried along with the SDUs. For example, multiple SDUs of the same PDU Set from the same QoS flow can be transmitted synchronously. For multiple SDUs from multiple QoS flows, synchronous transfer indication information carried along with the SDUs can be a set or a certain range of timestamp, sequence number (SN) , or synchronization sequence number (SSN) information associated with the SDUs for synchronous transfer. The range can be predefined or configurable. Then, the SDAP PDU and synchronous transfer indication information are sent to the lower-layer PDCP entity together by the SDAP entity. The synchronous transfer indication information here can be the synchronous transfer indication information carried along with the SDUs of the QoS flows, or the synchronous transfer indication information that is transformed but is functionally equivalent or similar.

There are two methods to support the enhanced encapsulation function for PDCP entity:

Method 1: Control-plane-based configuration.

When the PDCP entity needs to support the enhanced encapsulation function, it is necessary to configure the relevant information for the enhanced encapsulation function to the transmitting and receiving PDCP entities (i.e., the PDCP layer entity in the transmitter device and the PDCP layer entity in the receiver device) . Specifically, for the UE side, the gNB can configure the relevant information for the PDCP enhanced encapsulation function to the PDCP entity through a downlink control signal, such as a RRC message. As an embodiment, the relevant configuration information for enhanced encapsulation function is introduced based on the existing PDCP configuration information element (IE) in the standard. The required configuration information includes at least the configuration information to enable enhanced encapsulation function for SDU concatenation for synchronous transfer in the PDCP entity for uplink and/or downlink.

For the PDCP entity configured with enhanced encapsulation function for synchronous transfer, the transmitting and receiving PDCP entities can use one or more enhanced PDCP PDU formats to support the SDU multiplexing based on current PDCP PDU formats. Some examples of the enhanced PDCP PDU formats are designed as illustrated in FIG. 12 and FIG. 13 based on that in current technical specification (TS) of 38.323 of 3GPP.

Fields in the PDU formats are detailed in the following:

L: The Length field indicates the length of the corresponding PDCP SDU in bytes.

E: The Extension field is a flag indicating if the corresponding PDCP SDU is the last PDCP SDU or not in the PDCP PDU. The E field is set to "1" to indicate at least another PDCP PDU follows. The E field is set to "0" to indicate that the PDCP PDU is the last one;

The other field is the same as that in current technical specification TS 38.323 in 3GPP.

For the transmitting PDCP entity, which is configured and enabled with enhanced encapsulation function, the PDCP entity may encapsulate multiple SDUs into a single PDCP PDU based on received SDUs and relevant synchronous transfer indication information. The synchronous transfer indication information may comprise a set or a certain range of timestamp, sequence number (SN) , or synchronization sequence number (SSN) information associated with the SDUs for synchronous transfer. The range can be predefined or configurable. Then PDCP PDU then is send to the lower protocol entity with an enhanced PDU format for including multiple SDUs.

Further, if the length of two or more SDUs encapsulated into PDCP PDU is longer than the limitation of the maximum size of a single PDCP PDU, the transmitting PDCP entity can encapsulate the multiple SDUs into multiple PDCP PDUs.

At the receiving PDCP entity, based on the relevant configuration for enhanced encapsulation function, the PDCP PDUs are decapsulated into one or multiple SDUs according to the PDCP PDU format, and the receiving PDCP entity sends them to the SDAP protocol entity in the form of SDAP PDU. Decapsulation may include header removing and a reversion operation of SDU concatenation.

Method 2: User-plane-based indication.

For the user-plane-based indication for enhanced encapsulation function for synchronous transfer, based on current PDCP PDU formats, the transmitting and receiving PDCP entities should support one or more enhanced PDCP PDU formats which can indicate whether a PDCP PDU includes multiple SDUs or not. Some examples of the enhanced PDCP PDU formats are designed as illustrated in FIG. 14 and FIG. 15 based on that in current technical specification TS 38.323 of 3GPP.

One or more following methods can be used to confirm whether the transmitting and receiving PDCP entities support the user-plane-based indication for enhanced encapsulation function for synchronous transfer:

● A gNB informs UE of supporting of enhanced encapsulation function and the related enhanced PDCP PDU formats by transmitting explicitly or implicitly broadcasting system information (e.g., system information block (SIB) ) or dedicated RRC signaling to the UE. For example, the gNB informs the UE of a supported version of NR specification that defines one or more enhanced PDCP PDU formats and implicitly indicates.

● The UE reports UE capability to the gNB by dedicate RRC signaling. The UE capability shows that enhanced encapsulation function and the related enhanced PDCP PDU formats are supported by the UE.

● The gNB configures relevant information to the UE to enable the enhanced encapsulation function and the related enhanced PDCP PDU format supported by the UE based on the reported UE capability.

Fields in the PDU formats are detailed in the following:

MI: Multiplexing indicator indicate whether multiple SDUs are multiplexed in this PDU. The MI field is set to "1" to indicate more than one SDUs are multiplexed in this PDU and the enhanced PDU formats are used. The MI field is set to "0" to indicate the current PDU formats are used and only one SDU in this PDU.

L: The Length field indicates the length of the corresponding SDAP SDU in bytes.

E: The Extension field is a flag indicating if the corresponding SDAP SDU is the last SDAP SDU or not in the SDAP PDU. The E field is set to "1" to indicate at least another SDAP PDU follows. The E field is set to "0" to indicate that the SDAP PDU is the last one;

The other field is the same as that in current technical specification TS 38.323 of 3GPP.

For the transmitting PDCP entity, which is enabled with enhanced encapsulation function, the PDCP entity may encapsulate multiple SDUs into a single PDCP PDU based on received SDUs and relevant synchronous transfer indication information. The synchronous transfer indication information may comprise a set or a certain range of timestamp, sequence number (SN) , or synchronization sequence number (SSN) information associated with the SDUs for synchronous transfer. The range can be predefined or configurable. Then the MI field is set correspondingly for the PDU and the PDU is send to the lower protocol entity with the format for the SDU encapsulation.

The receiving PDCP entity which is enabled with enhanced encapsulation function can determine whether multiple SDUs are encapsulated in a PDU based on the value of MI field and process the PDU accordingly. The PDU may be decapsulated into multiple SDU (s) entity according to the enhanced PDCP PDU formats for the SDU multiplexing if MI is “1” or only one SDU in a PDU with current PDU formats if MI is “0” . The one or more SDUs is (are) sent to the SDAP protocol entity in the form of SDAP PDU. Decapsulation may include header removing and a reversion operation of SDU concatenation.

Embodiment 3: RLC MULTIPLEXING

In order to support RCL MULTIPLEXING (i.e., enhanced encapsulation function) :

● For the DRB onto which one or more QoS flows are mapped with synchronous transfer configuration, the transmitting SDAP and PDCP entity corresponding to the DRB identifies one or more SDUs which need to be transferred synchronously based on the synchronous transfer indication information associated with the one or more SDUs. For example, multiple SDUs of the same PDU Set from the same QoS flow can be transmitted synchronously. For multiple SDUs from multiple QoS flows which requires synchronous transfer, synchronous transfer indication information carried along with the SDUs may comprise a set or a certain range of timestamp, sequence number (SN) , or synchronization sequence number (SSN) information associated with the SDUs for synchronous transfer. The range can be predefined or configurable.

● The transmitting SDAP and PDCP layer entities need to maintain the association between SDU and/or PDU and the corresponding synchronous transfer indication information when processing SDU (s) , including receiving SDUs from the upper layer entity and forming PDUs to send to the lower layer entity. The synchronous transfer indication information here can be the synchronous transfer indication information carried along with the SDUs of the QoS flow, or synchronous transfer indication information that is transformed but is functionally equivalent or similar.

The basic principle for enhanced encapsulation function in RLC layer is similar to that in PDCP layer. For the CP-based configuration-based solution, it is necessary to configure the relevant information for the enhanced encapsulation function to the transmitting and receiving RLC entities with the methods similar to that for PDCP multiplexing. The transmitting and receiving RLC entities (i.e., the RLC layer entity in the transmitter device and the RLC layer entity in the receiver device) can use one or more enhanced RLC PDU formats to support the enhanced encapsulation function to encapsulate SDUs based on current RLC PDU formats. Some examples of the enhanced RLC PDU formats are designed as illustrated in FIG. 16 to FIG. 21 based on that in current technical specification TS 38.322 of 3GPP.

Fields in the PDU formats are detailed in the following:

L: The Length field indicates the length of the corresponding RLC SDU in bytes.

E: The Extension field is a flag indicating if the corresponding RLC SDU is the last RLC SDU or not in the RLC PDU. The E field is set to "1" to indicate at least another RLC PDU follows. The E field is set to "0" to indicate that the RLC PDU is the last one;

The other field is the same as that in current technical specification TS 38.322 in 3GPP.

Similarly, for the transmitting RLC entity, which is configured and enabled with enhanced encapsulation function, the RLC entity may encapsulate multiple SDUs into a single RLC PDU based on received SDUs and relevant synchronous transfer indication information. The synchronous transfer indication information may comprise a set or a certain range of timestamp, sequence number (SN) , or synchronization sequence number (SSN) information associated with the SDUs for synchronous transfer. The range can be predefined or configurable. Then RLC PDU then is send to the lower protocol entity with the format for the SDU encapsulation.

Further, if the length of two or more SDUs encapsulated into RLC PDU is longer than the limitation of the maximum size of a single RLC PDU, the transmitting RLC entity can multiplex the multiple SDUs into multiple RLC PDUs.

At the receiving RLC entity, based on the relevant configuration for enhanced encapsulation function, the RLC PDUs are decapsulated one or multiple SDUs according to the RLC PDU format, and the receiving RLC entity sends them to the PDCP protocol entity in the form of PDCP PDU. Decapsulation may include header removing and a reversion operation of SDU concatenation.

Embodiment 4: MAC MULTIPLEXING

MAC multiplexing (i.e., enhanced encapsulation function) can be applicable to multiplex the multiple SDUs from the same DRB or from multiple DRBs for the same UE. In order to support MAC multiplexing:

● For each DRB which is involved in the multiplexing for synchronous transfer, the transmitting SDAP, PDCP and RLC entity corresponding to the DRB identifies one or more SDUs which need to be transmitted synchronously based on the synchronous transfer indication information carried along with the SDU (s) . For example, multiple SDUs of the same PDU Set from the same QoS flow can be transmitted synchronously. For multiple SDUs from multiple QoS flows, synchronous transfer indication information carried along with the SDUs may comprise a set or a certain range of timestamp, sequence number (SN) , or synchronization sequence number (SSN) information associated with the SDUs for synchronous transfer. The range can be predefined or configurable.

● The transmitting SDAP, PDCP, and RLC layer entities need to maintain the association between SDU and/or PDU and the corresponding synchronous transfer indication information when processing SDU (s) , encapsulating receiving SDUs from the upper layer entity and forming PDUs to send to the lower layer entity, in order to enable MAC layer entity scheduling for synchronous transfer. The synchronous transfer indication information here can be the synchronous transfer indication information carried along with the SDUs of the QoS flow, or synchronous transfer indication information that is transformed but is functionally equivalent or similar.

For the cases that encapsulating or multiplexing multiple SDUs for synchronous transfer from multiple DRBs for a single UE, a synchronous DRB group can be configured to establish synchronization relationships between DRBs. One DRB of them can be configured as primary DRB which will be the reference for the synchronous operation, such as synchronization configuration, synchronization detection, and synchronous transfer. The primary DRB can be also named as reference DRB. The configuration information for the synchronous DRB group includes one or more of the following:

● a synchronous DRB group ID of the synchronous DRB group;

● DRB IDs of the member DRBs in the synchronous DRB group; and

The timing information comprise one or more of periodicity, jitter, and data arrival time of the primary DRB.

It is also possible to configure synchronous transfer relationships between multiple DRBs based on the logical channel group (LCG) which comprises the logical channels (LCHs) corresponding to the DRBs. That is, logical channels with synchronous transfer relationships can be mapped to the same LCG, and one or more primary logical channels can be optionally configured for the LCG. The configuration information for LCG includes one or more of the following:

● a synchronous LCG ID of the LCG;

● LCH IDs of member LCHs in the LCG;

The timing information comprise one or more of periodicity, jitter, and data arrival time for the data corresponding to the primary QoS flow/DRB.

Among the LCHs in an LCG, one of the LCHs is a primary LCH that carries a media component of a multi-modal service, such as XR service, and is used as a reference for other LCHs that carries media components of the multi-modal service for the synchronous operation, such as synchronization configuration, synchronization detection, and synchronous transfer.

The aforementioned configuration for synchronized transmission between DRBs applies to both uplink (UE to gNB) and downlink (gNB to UE) transmissions. For uplink synchronous DRB group or synchronous LCG, the gNB can configure the aforementioned synchronous DRB group or LCG information to the UE through a downlink control signal, such as a RRC message. In an embodiment of the invention, Radio resource scheduling for SDUs of the primary DRB is prioritized over radio resource scheduling for SDUs of the member DRBs.

● Downlink multiplexing for synchronous transfer:

When the MAC layer entity is performing downlink transmission scheduling, for the same DRB, if multiple RLC SDUs or PDUs have the same or related synchronous transfer indication information, these RLC SDUs or PDUs are multiplexed together into one or adjacent/nearby multiple MAC PDUs as much as possible.

For multiple DRBs, according to the configuration for the synchronous DRB groups or the synchronous LCG, one or more RLC SDUs or PDUs in the primary DRB are scheduled first, then one or more RLC SDUs or PDUs in other member DRBs of the synchronous DRB group with the same or related synchronous transfer indication information are scheduled, and these RLC SDUs or PDUs are multiplexed together into one or adjacent/nearby multiple MAC PDUs.

● Uplink multiplexing for synchronous transfer:

To support uplink transmission scheduling, the UE reports the buffer status of data packets to the gNB via BSR. For synchronous transfer based on synchronous DRB group or LCG. The LCG based BSR (Buffer Status Report) mechanism can be further enhanced for the synchronous transfer.

Embodiment 4.1: Reporting buffer size for the pending data based on different time ranges in the BSR.

To report buffer size for the pending data based on different time ranges in the BSR, a BSR needs to include one or more of the following information:

● a LCG ID: LCG identifier;

● buffer sizes for one or more time ranges; and

● information about the one or more time ranges corresponding to the buffer sizes: the value of each time range, or indication information for each time range, such as the index to look up the real value of range in a table, the sequence number information for a series of predefined time range.

The following is an example in which the buffer size is calculated and reported based on the one or more period (s) of the primary QoS flow.

A multi-mode service consists of three different QoS flows (audio, visual, and tactile) with different QoS flow Identifiers (QFIs) of 1, 2, and 3, respectively. These three QoS flows are mapped to the same DRB and correspond to the same LCH (ID=1) and LCG (ID=1) , or they are mapped to different DRBs and correspond to different LCHs (IDs 1, 2, and 3) , but they are all mapped to the same LCG (ID=1) . The data packets of these three QoS flows are periodic, but with different periods. As shown in the FIG. 22, the audio flow is used as the primary QoS flow, DRB, or LCH to calculate the buffer sizes based on the different periodicities of audio data packets, and the transmitting MAC entity reports the calculated buffer sizes together in one BSR. The buffer size for each period includes all packets that require synchronous transfer within that period. Taking the packets (one PDU or PDU Set) earliest arriving as a reference point, the buffer size for the data arriving in the first period is counted as the buffer size for the first period (or first cycle) , the buffer size for the data packets arriving in the second period is counted as the buffer size for the second period (or second cycle) , and so on. The results for each cycle period are shown in the table below.

Table 2

With reference to FIG. 23, in order to report buffer sizes based on different time ranges in a BSR, an example enhanced BSR format which only supports 5 time ranges is shown, and here the ranges are the different cycles or periods. A value of each field is enclosed in brackets.

Embodiment 4.2: reporting the buffer size with the consideration about the synchronization requirement between different QoS flows:

The following is an example in which the buffer size is calculated and reported with the consideration about the periodicity and the synchronization requirement between primary QoS flow and member QoS flows.

The following table shows the synchronization requirement between an audio, visual and tactile flow:

Table 3

In the example, the audio flow is the primary QoS flow, and the synchronization requirement can be shown as the following table:

Table 4

A multi-mode service consists of three different QoS flows (audio, visual, and tactile) with different QoS flow identifiers (QFIs) of 1, 2, and 3, respectively. These three QoS flows are mapped to the same DRB and correspond to the same LCH (ID=1) and LCG (ID=1) , or they are mapped to different DRBs and correspond to different LCHs (IDs 1, 2, and 3) , but they are all mapped to the same LCG (ID=1) . The data packets of these three QoS flows are periodic, but with different periods. As shown in the FIG. 24, the audio flow is conveyed as the primary QoS flow, DRB, or LCH. The synchronization delay requirement for visual and tactile QoS flow compared to the audio QoS flow is 20ms and 25ms respectively.

A periodic BSR is configured with the periodicity of audio QoS flow for the BSR, and the buffer size is configured to be calculated based on the periodic audio QoS flow packets (PDU or PDU Set) and the maximum synchronization delay between all the QoS flow. That is, the buffer size is calculated based on the audio (voice) QoS flow data packets for each period and other QoS flow data packets within a 25-millisecond range thereafter. As shown in the FIG. 24, the corresponding buffer size reported for each period BSR are 100, 120, 60 and 30 bytes respectively, and in the third and fourth period, there are 70 and 30 bytes of data packets may be discarded respectively because those data packets exceed the maximum synchronization delay requirement.

Embodiment 4.3: detecting and reporting for the out-of-synchronization of the uplink synchronous transfer.

In order to enable gNB to schedule uplink synchronous transfer more efficiently, UE can detect the out-of-synchronization of the uplink synchronous transfer and report the status information of out-of-synchronization to gNB.

The MAC entity for uplink synchronous transfer can detect whether two or more arrived SDUs are out-of-synchronization based on the synchronous transfer indication information of the SDUs and/or the configured synchronization requirement. As illustrated in FIG. 25, according to the synchronous transfer indication information, PDU Set2 from LCH1 and LCH2 should be transmitted synchronously. The MAC entity can compare the arrival time difference of those two PDU Set2 with the configured synchronization requirement. As an embodiment, the configured synchronization requirement can be a synchronization threshold. When the arrival time differences Diff-time between two or more SDUs are greater than the synchronization threshold, the MAC entity may determine that those SDUs are out-of-synchronization. In one embodiment, the SDU from a primary LCH is regarded as the reference for the comparison with other SDUs from other LCH.

When an out-of-synchronization event occurs, a trigger can be initiated to report the status information of the event to the gNB. This trigger can be a Block Status Report (BSR) for the out-of-synchronization status information.

In another embodiment, a trigger for BSR for the out-of-synchronization status information can be initiated if the number of out-of-synchronization events occurring within a predefined or configured time range exceeds a predefined or configured threshold.

In an alternative embodiment, if a ratio of out-of-synchronization SDUs to synchronized SDUs, or the total number of out-of-synchronization SDUs within a pre-defined or configured time range exceeds a pre-defined or configured threshold, a trigger for Block Status Report (BSR) can be initiated to provide status information regarding the out-of-synchronization SDUs.

To report the status information of out-of-synchronization, a new MAC CE for BSR for the status information of out-of-synchronization should be defined. Some examples are defined as illustrated in FIG. 26 and FIG. 27.

As shown in FIG. 26, a one-bit indicator which is named as Async indi for the status of out-of-synchronization is introduced for each LCG. When out-of-synchronization event occurs for one LCG, the corresponding “Async indi” indicator should be set as “1” , or “0” .

As shown in FIG. 27, apart from the one-bit indicator, one-byte parameter which is named as Diff-time is also introduced for each LCG to report the status information of out-of-synchronization. When out-of-synchronization event occurs for one LCG, the corresponding indicator should be set as “1” , and at the same time, the corresponding Diff-time parameter is included in the same BSR. Otherwise, the corresponding indicator should be set as “0” , and no corresponding Diff-time parameter is included in the same BSR. The reported Diff-time value can be the maximum or average or minimum value among multiple values between multiple SDUs.

In another embodiment, the Diff-time can be a row or column index of a table in which the real differ time is defined for each index. The table can be designed in a linear or exponential increasing manner.

In another embodiment, the ratio of out-of-synchronization SDUs to synchronized SDUs, or the total number of out-of-synchronization SDUs within a pre-defined or configured time range can be also reported in the BSR.

Embodiment 5: LCP AND TIMING

For uplink transmission using Configured Grant (CG) resources, especially when using the Multiple-PUSCHs CG (Multiple CG PUSCH transmission occasions in a period of a single CG PUSCH configuration) resources, the data packets in the buffer can be handled in one or more of the following methods, which are applicable to the above-mentioned MAC multiplexing method:

The data packets in the buffer are scheduled for uplink transmission in the order of the remaining time of the data packets in the Multiple-PUSCHs CG resource in the time domain. The MAC layer performs logical channel prioritization (LCP) in which a data packet with a smaller remaining time is transmitted using an earlier transmission occasion or an earlier multiple-physical uplink shared channel (PUSCH) configured grant (CG) than a data packet with a greater remaining time, the remaining time is used to evaluate time required by one or more data packets to be transmitted on a Uu interface. For example, among multiple transmission occasions (TO) in a Multiple-PUSCHs CG resource, the data packet with a smaller remaining time is transmitted using the earlier TO in time domain, while the data packet with a greater remaining time is transmitted using the later TO in time domain. Alternatively, among multiple Multiple-PUSCHs CG resources, the data packet with a smaller remaining time is transmitted using the earlier Multiple-PUSCHs CG resource in time domain, while the data packet with a greater remaining time is transmitted using the later Multiple-PUSCHs CG resource in time domain. The remaining time is used to evaluate the time left on the plan by one or more data packets to be transmitted on the Uu interface, which can be based on a timer for a certain SDU, PDU, or PDU set, such as the discard timer, or the PDB (Packet Delay Budget) for a certain SDU or PDU, or the PSDB (PDU Set Delay Budget) for a PDU set. A packet may be an SDU or a PDU.

For the same DRB, if multiple RLC SDUs or PDUs have the same or related synchronous transfer indication information, they are preferably encapsulated into one or more adjacent/following MAC PDUs and transmitted in one or more adjacent/following TOs. For multiple DRBs, according to the configuration of the synchronous DRB group or multiple DRBs or LCG, one or more RLC SDUs or PDUs with the same or related synchronous transfer indication information in the primary DRB can be prioritized for scheduling, followed by one or more RLC SDUs or PDUs with the same or related synchronous transfer indication information in other member DRBs, and these RLC SDUs or PDUs are encapsulated into one or more adjacent/following MAC PDUs and transmitted in one or more adjacent/following TOs. These adjacent/following TOs can be multiple TOs within a Multiple-PUSCHs CG or multiple TOs among multiple Multiple-PUSCHs CGs. The MAC layer performs logical channel prioritization (LCP) in which radio resource scheduling for a packet with the same or related synchronous transfer indication information in a primary DRB in a DRB group is prioritized over radio resource scheduling for a packet with the same or related synchronous transfer indication information in a member DRB in the DRB group. The prioritized packet is transferred using an earlier transmission occasion or an earlier multiple-physical uplink shared channel (PUSCH) configured grant (CG) .

For multiple DRBs or LCHs with synchronous transfer requirements and different priorities, the following may apply:

● In radio resource scheduling for packets in multiple DRBs or LCHs with synchronous transfer requirements and different priorities, the MAC layer performs logical channel prioritization (LCP) based on priority of a primary DRB in a DRB group or a primary LCH in an LCG.

● In an embodiment of the invention, the MAC layer performs logical channel prioritization (LCP) in which when radio resource scheduling for packets based on synchronous transfer requirements of packets conflicts with radio resource scheduling for packets based on priority of packets, radio resource scheduling for packets based on synchronous transfer requirements of packets is prioritized over radio resource scheduling for packets based on priority of packets.

● In an embodiment of the invention, radio resource scheduling for packets based on synchronous transfer requirements of packets is prioritized over radio resource scheduling for packets based on priority of packets.

● For example, the out-of-synchronization event may be triggered when delay of packets of different media components of a service with the synchronous transfer requirements exceeds a predetermined threshold. The threshold also can be configured by gNB to UE via a downlink control signal, such as a RRC message.

Embodiment 6: PACKET DISCARDING

For the received data packets that exceed the synchronous transfer requirements between different QoS flows of the service, one or more of the following processes can be applied for the above SDAP, PDCP, or MAC multiplexing methods:

● The protocol layer entity discards the data packet.

● The protocol layer entity processes packet discarding according to the configuration information. If discard operation is configured for received data packets that exceed the synchronous transfer requirements, the MAC layer entity discards the data packets. Otherwise, the protocol layer entity processes the data packet normally. For uplink transmission, the configuration information is sent to UE by gNB through a downlink control signal, such as a RRC message.

● If the received data packets exceed the synchronous transfer requirements by a predetermined threshold, the protocol layer discards the data packets. Otherwise, the MAC layer entity processes the data packet normally. For uplink transmission, the predetermined threshold is either predefined by the standard, or calculated based on the synchronous requirement parameters, such as calculated based on a ratio that is predefined or sent to UE by gNB through a downlink control signal, such as a RRC message, or the predetermined threshold is sent to UE by gNB through a downlink control signal, such as a RRC message.

In an embodiment of the invention, the protocol layer performs packet discarding for packets of different QoS flows with synchronization requirements, different DRBs with synchronization requirements, or different LCHs with synchronization requirements based on one or more of the following attributes:

● priorities of the different QoS flows with synchronization requirements, different DRBs with synchronization requirements, or different LCHs with synchronization requirements;

● importance of the different QoS flows with synchronization requirements, different DRBs with synchronization requirements, or different LCHs with synchronization requirements.

In an embodiment of the invention, the protocol layer is a service data adaption protocol (SDAP) layer, a Packet Data Convergence Protocol (PDCP) layer, a Radio Link Control (RLC) layer, and/or a medium access control (MAC) layer. The protocol layer performs packet discarding for packets of different QoS flows with synchronization requirements based on one or more of the following attributes:

● priorities of the different QoS flows with synchronization requirements;

● importance of the different QoS flows with synchronization requirements;

● membership of a QoS flow that carries at least one of the packets, wherein the membership indicates whether the QoS flow is a primary QoS flow among the different QoS flows; and

● a parameter of synchronous transfer of the packets and a threshold of the parameter.

In an embodiment of the invention, the protocol layer is a Packet Data Convergence Protocol (PDCP) layer or a Radio Link Control (RLC) layer. The protocol layer performs packet discarding for packets of different DRBs with synchronization requirements based on one or more of the following attributes:

● priorities of the different DRBs with synchronization requirements;

● importance of the different DRBs with synchronization requirements;

● membership of a DRB that carries at least one of the packets, wherein the membership indicates whether the DRB is a primary DRB among the different DRBs; and

In an embodiment of the invention, the protocol layer is a medium access control (MAC) layer; the protocol layer performs packet discarding for packets of different LCHs with synchronization requirements based on one or more of the following attributes:

● priorities of the different LCHs with synchronization requirements;

● importance of the different LCHs with synchronization requirements;

● membership of a LCH that carries at least one of the packets, wherein the membership indicates whether the LCH is a primary LCH among the different LCHs; and

In an embodiment of the invention, the threshold of the parameter is provided in a downlink control signal, such as a RRC message. In an embodiment of the invention, one or more of the attributes are enabled according to configuration for the packet discarding.

On the other hand, when transmission congestion happens, data packets between multiple QoS flow/DRB/LCH with synchronous transfer requirements can be processed according to one or more of the following methods, which are applicable to the above SDAP, PDCP, and MAC multiplexing methods:

● The protocol layer discards data packets based on the priority or importance of QoS flow/DRB/LCH regardless of the synchronous transfer requirements.

● The protocol layer discards the data packets from member QoS flows/DRBs/LCHs of the synchronous QoS flows, DRBs or LCHs based on priority or importance while the protocol layer transmits the data packets from the primary QoS flow/DRB/LCH normally.

● The protocol layer discards the data packets from one or more QoS flow/DRB/LCH of the synchronous QoS flows, DRBs or LCHs according to the indication information from gNB to UE dynamically, such as via MAC CE or DCI. The indication information can be a threshold related to a parameter for synchronous transfer, such as a value or an index for the value of the priority or importance. The data packets for which the parameter is greater than or less than the threshold can be discarded.

● The protocol layer performs packet discarding according to configuration information. For example, in a configuration, the protocol layer discards data packet based on the priority or importance of QoS flow/DRB/LCH. As another option, the protocol layer may apply a selective discard policy to the data packets belonging to the member QoS flows/DRBs/LCHs of the synchronized QoS flows/DRBs/LCHs according to their priority or relevance, while ensuring the normal transmission of the data packets belonging to the primary QoS flow/DRB/LCH. For uplink transmission, the configuration information is sent to UE by gNB through a downlink control signal, such as a RRC message.

● As another option, the protocol layer may apply a selective discard policy to the data packets belonging to the member QoS flows/DRBs/LCHs of the synchronized QoS flows/DRBs/LCHs according to their priority or importance (or relevance) , while ensuring the normal transmission of the data packets belonging to the primary QoS flow/DRB/LCH.

After the data packets are discarded, one or more of the following processes can be performed:

● The transmitting entity sends the information about the discarded data packets, such as SN information, to the receiving entity through the corresponding control PDU, and the receiving entity adjusts the receiving window based on the received SN information.

● For uplink transmission based on MAC multiplexing, triggering the generation of a new BSR; or when the discarded data packet size exceeds a predetermined threshold, triggering a new BSR, where the predetermined threshold is predefined or sent to UE by gNB through a downlink control signal, such as a RRC message.

● For uplink transmission based on MAC multiplexing, if a BSR that already exists is entirely or partially triggered due to the discarded data packets, the protocol layer cancels the BSR and the related SR.

Embodiment 7: uplink service awareness information reporting

In order to configure the uplink synchronous transfer, the UE can send uplink service awareness information to the gNB in one of the following:

● UE assistant information (UAI) ;

● a medium access control (MAC) control element (CE) ; and

● uplink control information (UCI) .

The uplink service awareness information is transmitted from a user equipment (UE) to a base station and includes one or more of the following types of information:

● information of a primary QoS flow and information of member QoS flows, wherein the member QoS flows need to be transferred synchronously with the primary QoS flow;

● information of a primary DRB and information of member DRBs, wherein the member DRBs need to be transferred synchronously with the primary DRB; or

● information of a primary LCH and information of member LCHs, wherein the member LCHs need to be transferred synchronously with the primary LCH.

The information of the primary QoS flow comprises QoS flow ID, periodicity, jitter, data arrival time of the primary QoS flow, and the information of the member QoS flows comprises QoS flow ID, periodicity, jitter, data arrival time of each of the member QoS flows.

The information of the primary DRB comprises DRB ID, periodicity, jitter, data arrival time of the primary DRB, and the information of the member DRBs comprises DRB ID, periodicity, jitter, data arrival time of each of the member DRBs.

The information of the primary LCH comprises LCH ID, periodicity, jitter, data arrival time of the primary LCH, and the information of the member LCHs comprises LCH ID, periodicity, jitter, data arrival time of each of the member LCHs.

The time occasions to send uplink service awareness information from UE to gNB includes one or more of the following:

● The uplink service awareness information is transmitted to the base station or gNB before relevant radio resource allocation for a service, that is, before the relevant RRC Reconfiguration process;

● Periodic reporting: The uplink service awareness information is transmitted to the base station or gNB periodically after relevant radio resource allocation for the service.

● Timer-based reporting: The UE may configure and start the timer in the relevant RRC reconfiguration process and report the uplink service awareness information when the timer times out. The uplink service awareness information is transmitted to the base station or gNB in response to expiration of a timer after relevant radio resource allocation for the service. If there is a new configuration procedure or other reasons that trigger the uplink service awareness information report before the timer times out, the timer is reset and restarted;

● If one or more the parameter (s) related to uplink service awareness information changes exceed one or more predetermined thresholds, the UE reports during the service is running after the radio resource allocation. The uplink service awareness information is transmitted to the base station or gNB when a change to the uplink service awareness information exceeds a threshold after relevant radio resource allocation for the service. These predetermined thresholds may be predefined by the standard. Alternatively, these predetermined thresholds are calculated based on the uplink service awareness information. For example, the threshold is represented as a proportion, where the proportion is predefined or sent to the UE by the gNB through a downlink control signal, such as a RRC message. These predetermined thresholds are sent to the UE by the gNB through a downlink control signal, such as a RRC message.

FIG. 28 is a block diagram of an example system 700 for wireless communication according to an embodiment of the present disclosure. Embodiments described herein may be implemented into the system using any suitably configured hardware and/or software. FIG. 28 illustrates the system 700 including a radio frequency (RF) circuitry 710, a baseband circuitry 720, a processing unit 730, a memory/storage 740, a display 750, a camera 760, a sensor 770, and an input/output (I/O) interface 780, coupled with each other as illustrated.

The processing unit 730 may include circuitry, such as, but not limited to, one or more single-core or multi-core processors. The processors may include any combinations of general-purpose processors and dedicated processors, such as graphics processors and application processors. The processors may be coupled with the memory/storage and configured to execute instructions stored in the memory/storage to enable various applications and/or operating systems running on the system.

The radio control functions may include, but are not limited to, signal modulation, encoding, decoding, radio frequency shifting, etc. In some embodiments, the baseband circuitry may provide for communication compatible with one or more radio technologies. For example, in some embodiments, the baseband circuitry may support communication with 5G NR, LTE, an evolved universal terrestrial radio access network (EUTRAN) and/or other wireless metropolitan area networks (WMAN) , a wireless local area network (WLAN) , a wireless personal area network (WPAN) . Embodiments in which the baseband circuitry is configured to support radio communications of more than one wireless protocol may be referred to as multi-mode baseband circuitry. In various embodiments, the baseband circuitry 720 may include circuitry to operate with signals that are not strictly considered as being in a baseband frequency. For example, in some embodiments, baseband circuitry may include circuitry to operate with signals having an intermediate frequency, which is between a baseband frequency and a radio frequency.

In various embodiments, the system 700 may be a mobile computing device such as, but not limited to, a laptop computing device, a tablet computing device, a netbook, an ultrabook, a smartphone, etc. In various embodiments, the system may have more or less components, and/or different architectures. Where appropriate, the methods described herein may be implemented as a computer program. The computer program may be stored on a storage medium, such as a non-transitory storage medium.

The embodiment of the present disclosure is a combination of techniques/processes that can be adopted in 3GPP specification to create an end product.

If the software function unit is realized and used and sold as a product, it can be stored in a readable storage medium in a computer. Based on this understanding, the technical plan proposed by the present disclosure can be essentially or partially realized as the form of a software product. Or, one part of the technical plan beneficial to the conventional technology can be realized as the form of a software product. The software product in the computer is stored in a storage medium, including a plurality of commands for a computational device (such as a personal computer, a server, or a network device) to run all or some of the steps disclosed by the embodiments of the present disclosure. The storage medium includes a USB disk, a mobile hard disk, a read-only memory (ROM) , a random-access memory (RAM) , a floppy disk, or other kinds of media capable of storing program codes.

While the present disclosure has been described in connection with what is considered the most practical and preferred embodiments, it is understood that the present disclosure is not limited to the disclosed embodiments but is intended to cover various arrangements made without departing from the scope of the broadest interpretation of the appended claims.

Claims

A wireless communication method for wireless communication device, comprising:

receiving multiple service data units (SDUs) for synchronous transfer and synchronous transfer indication information from an upper protocol layer;

encapsulating the multiple SDUs into one or more protocol data units (PDUs) in a protocol layer for synchronous transfer based on the synchronous transfer indication information; and

providing the one or more PDUs to a lower protocol layer for synchronous transfer.
The wireless communication method of claim 1, wherein when concatenation of the multiple SDUs does not exceed the maximum payload size of one PDU of the protocol layer, the multiple SDUs are encapsulated into one PDU of the protocol layer in an enhanced PDU format; and

when concatenation of the multiple SDUs exceeds the maximum payload size of one PDU of the protocol layer, the multiple SDUs are encapsulated into multiple PDUs of the protocol layer in the enhanced PDU format.
The wireless communication method of claim 2, wherein a control plane signal is transmitted to indicates whether the PDU formats supporting multiple SDUs are used for synchronous transfer.
The wireless communication method of claim 2, wherein a field in the enhanced PDU formats of the one or more PDUs indicates whether the PDU formats supporting multiple SDUs are used for synchronous transfer.
The wireless communication method of claim 2, wherein the enhanced PDU format is enabled based on a set of enhanced PDU formats supported by a user equipment (UE) in a UE capability report and/or a set of enhanced PDU formats supported by a base station in a broadcast or unicast downlink indication message.
The wireless communication method of claim 1, wherein the encapsulating the multiple SDUs into one or more PDUs for synchronous transfer based on synchronous transfer indication information is performed when an enhanced encapsulation function is enabled according to configuration information; and

the configuration information is conveyed in a radio resource control (RRC) message, or

the configuration information includes a control plane signal and conveyed in a radio resource control (RRC) message, wherein a control plane signal is transmitted to indicates whether the PDU formats supporting multiple SDUs are used for synchronous transfer.
The wireless communication method of claim 6, wherein the protocol layer is a service data adaption protocol (SDAP) ;

the configuration information of the enhanced encapsulation function further comprises one or more instances of following information:

quality of service (QoS) flow identification of QoS flows associated with the SDUs for synchronous transfer; and

the configuration information for synchronous transfer requirement which at least includes a delay threshold between QoS flows.
The wireless communication method of claim 6, wherein the protocol layer is a medium access control (MAC) layer;

the configuration information of the enhanced encapsulation function further comprises one or more of:

a data radio bearer (DRB) group or multiple DRB configured to establish synchronization relationships between DRB;

a logical channel group (LCG) configured to establish synchronization relationships between logical channels; and

the configuration information about a delay threshold between QoS flows for synchronous transfer.
The wireless communication method of claim 8, wherein configuration information for the DRB group or multiple DRB includes one or more of the following:

a DRB group ID of the synchronous DRB group;

DRB IDs of the member DRBs in the synchronous DRB group or multiple DRB; and

primary DRB information which comprises a primary DRB ID and timing information of a primary DRB in the synchronous DRB group.
The wireless communication method of claim 8, wherein configuration information for the LCG includes one or more of the following:

a LCG ID of the LCG;

LCH IDs of member LCHs in the LCG;

primary LCH information which comprises a primary LCH ID and timing information of a primary LCH in the LCG.
The wireless communication method of claim 9 or 10, wherein the timing information comprise one or more of periodicity, jitter and data arrival time for the data corresponding to the primary DRB or the primary QoS flow.
The wireless communication method of claim 8, wherein for synchronous uplink transmission scheduling, the MAC layer performs buffer size reporting (BSR) using a buffer size report (BSR) based on one or more instances of the following information:

a LCG ID;

one or more buffer size (s) according to one or more time ranges based on periodicity of one QoS flow/DRB data packets;

one or more buffer size (s) for the buffered data complied with the configuration information for synchronous transfer requirement; and

one or more synchronization status information between different QoS flows, which comprises an out-of-synchronization indication which indicates whether data from a DRB/QoS flow is in synchronization or not relative to the data from the primary DRB/QoS flow; and a Differ time which is a data arrival time difference between a QoS flow and the primary DRB/QoS flow.
The wireless communication method of claim 8, wherein the MAC layer performs out-of-synchronization event detection based on the synchronous transfer indication information and triggers reporting of an out-of-synchronization event or a BSR for out-of-synchronization event reporting when detecting the out-of-synchronization event or when a number of out-of-synchronization events occurring within a predefined or configured time range exceeds a predefined or configured threshold or when a ratio of out-of-synchronization SDUs to synchronized SDUs exceeds a pre-defined or configured threshold.
The wireless communication method of claim 13, wherein the BSR for out-of-synchronization event reporting comprises for each LCG in the BSR one or more of:

one indicator that indicate whether an out-of-synchronization event occurs in the LCG;

a difference between arrival times of two or more SDUs of different streams of a service in the out-of-synchronization event; and

a ratio of out-of-synchronization SDUs to synchronized SDUs, or a total number of SDUs within a pre-defined or configured time range.
The wireless communication method of claim 8, wherein the MAC layer performs logical channel prioritization (LCP) in which a data packet with a smaller remaining time is transferred using an earlier transmission occasion or an earlier multiple-physical uplink shared channel (PUSCH) configured grant (CG) than a data packet with a greater remaining time, the remaining time is used to evaluate time left on the plan by one or more data packets to be transmitted on a Uu interface.
The wireless communication method of claim 8 or 9 , wherein the MAC layer performs logical channel prioritization (LCP) in which radio resource scheduling for a packet with the same or related synchronous transfer indication information in a primary DRB in a DRB group is prioritized over radio resource scheduling for a packet with the same or related synchronous transfer indication information in a member DRB in the DRB group, the prioritized packet is transferred using an earlier transmission occasion or an earlier multiple-physical uplink shared channel (PUSCH) configured grant (CG) .
The wireless communication method of claim 8, wherein in radio resource scheduling for packets in multiple DRBs or LCHs with synchronous transfer requirements and different priorities, the MAC layer performs logical channel prioritization (LCP) based on priority of a primary DRB in a DRB group or a primary LCH in a LCG.
The wireless communication method of claim 8, wherein the MAC layer performs logical channel prioritization (LCP) in which when radio resource scheduling for packets based on synchronous transfer requirements of packets conflicts with radio resource scheduling for packets based on priority of packets, radio resource scheduling for packets based on synchronous transfer requirements of packets is prioritized over radio resource scheduling for packets based on priority of packets.
The wireless communication method of claim 1, wherein the protocol layer performs packet discarding for packets of different QoS flows with synchronization requirements, different DRBs with synchronization requirements, or different LCHs with synchronization requirements based on one or more of the following attributes:

priorities of the different QoS flows with synchronization requirements, different DRBs with synchronization requirements, or different LCHs with synchronization requirements;

importance of the different QoS flows with synchronization requirements, different DRBs with synchronization requirements, or different LCHs with synchronization requirements.
The wireless communication method of claim 1, wherein the protocol layer is a service data adaption protocol (SDAP) layer, a Packet Data Convergence Protocol (PDCP) layer, a Radio Link Control (RLC) layer, and/or a medium access control (MAC) layer;

the protocol layer performs packet discarding for packets with synchronization requirements based on configuration for one or more of the following attributes:

priorities of the packets with synchronization requirements;

importance of the packets with synchronization requirements;

membership of a QoS flow/DRB/LCH that carries at least one of the packets, wherein the membership indicates whether the QoS flow/DRB/LCH is a primary QoS flow/DRB/LCH among the different QoS flows/DRB/LCH; and

a parameter of synchronous transfer of the packets and a threshold of the parameter.
The wireless communication method of claim 1, wherein uplink service awareness information is transmitted from a user equipment (UE) to a base station, and the uplink service awareness information comprises:

information of a primary QoS flow and/or information of member QoS flows, wherein the member QoS flows need to be transmitted synchronously with the primary QoS flow;

the information of the primary QoS flow comprises QoS flow ID, periodicity, jitter, data arrival time of the primary QoS flow, and the information of the member QoS flows comprises QoS flow ID, periodicity, jitter, data arrival time of each of the member QoS flows.
A wireless communication device comprising:

a processor configured to call and run a computer program stored in a memory, to cause a device in which the processor is installed to execute the method of any of claims 1 to 21.
A chip, comprising:

a processor, configured to call and run a computer program stored in a memory, to cause a device in which the chip is installed to execute the method of any of claims 1 to 21.
A computer-readable storage medium, in which a computer program is stored, wherein the computer program causes a computer to execute the method of any of claims 1 to 21.
A computer program product, comprising a computer program, wherein the computer program causes a computer to execute the method of any of claims 1 to 21.
A computer program, wherein the computer program causes a computer to execute the method of any of claims 1 to 21.
A wireless communication method for wireless communication device, comprising:

receiving one or more protocol data units (PDUs) for synchronous transfer from a lower protocol layer;

decapsulating the one or more PDUs into multiple service data units (SDUs) in a protocol layer for synchronous transfer based on configuration information for synchronous transfer and/or a PDU format of the PDUs for synchronous transfer; and

providing the multiple SDUs to an upper protocol layer for synchronous transfer.
The wireless communication method of claim 27, wherein concatenation of the multiple SDUs are encapsulated into one or more PDUs of the protocol layer in an enhanced PDU format.
The wireless communication method of claim 28, wherein a control plane signal is received to indicates whether the PDU format includes multiple SDUs for synchronous transfer.
The wireless communication method of claim 28, wherein a field in the enhanced PDU format of the one or more PDUs indicates whether the PDU format includes multiple SDUs for synchronous transfer.
The wireless communication method of claim 27, wherein the multiple SDUs are decapsulated from one or more PDUs for synchronous transfer based on an enhanced PDU format when an enhanced encapsulation function is enabled according to configuration information; and

the configuration information is conveyed in a radio resource control (RRC) message, or

the configuration information includes a control plane signal and conveyed in a radio resource control (RRC) message, wherein a control plane signal is transmitted to indicates whether the PDU formats supporting multiple SDUs are used for synchronous transfer.
The wireless communication method of claim 27, wherein the protocol layer is a service data adaption protocol (SDAP) ;

the configuration information of the enhanced encapsulation function further comprises one or more instances of following information:

quality of service (QoS) flow identification of QoS flows associated with the SDUs for synchronous transfer; and

the configuration information for synchronous transfer requirement which at least includes a delay threshold between QoS flows.
The wireless communication method of claim 27, wherein the protocol layer is a medium access control (MAC) layer;

the configuration information of the enhanced encapsulation function further comprises one or more of:

a data radio bearer (DRB) group or multiple DRB configured to establish synchronization relationships between DRB;

a logical channel group (LCG) which comprises the logical channels (LCHs) corresponding to the DRBs; and

the configuration information about a delay threshold between QoS flows for synchronous transfer.
The wireless communication method of claim 33, wherein configuration information for the synchronous DRB group or multiple DRB includes one or more of the following:

a DRB group ID of the synchronous DRB group;

DRB IDs of the member DRBs in the synchronous DRB group or multiple DRB; and

primary DRB information which comprises a primary DRB ID and timing information of a primary DRB in the synchronous DRB group.
The wireless communication method of claim 33, wherein configuration information for the LCG includes one or more of the following:

a synchronous LCG ID of the LCG;

LCH IDs of member LCHs in the LCG;

primary LCH information which comprises a primary LCH ID and timing information of a primary LCH in the LCG.
The wireless communication method of claim 34 or 35, wherein timing information comprise one or more of periodicity, jitter and data arrival time of for the data corresponding to the primary DRB of the primary QoS flow.
A wireless communication device comprising:

a processor configured to call and run a computer program stored in a memory, to cause a device in which the processor is installed to execute the method of any of claims 27 to 36.
A chip, comprising:

a processor, configured to call and run a computer program stored in a memory, to cause a device in which the chip is installed to execute the method of any of claims 27 to 36.
A computer-readable storage medium, in which a computer program is stored, wherein the computer program causes a computer to execute the method of any of claims 27 to 36.
A computer program product, comprising a computer program, wherein the computer program causes a computer to execute the method of any of claims 27 to 36.
A computer program, wherein the computer program causes a computer to execute the method of any of claims 27 to 36.