Transmission method and device suitable for augmented reality service, and storage medium

Abstract

The invention provides a transmission method and device suitable for an augmented reality service and a storage medium, and relates to the technical field of communication. The transmission method suitable for the augmented reality service comprises the following steps: establishing a packet data unit PDU session between user equipment UE and a core network, the PDU session realizing augmented reality XR service awareness based on a data unit group PDU Set, the PDU Set comprising one or more PDUs, and the PDU Set comprising one or more PDUs; the quality of service (QoS) parameter of the PDU Set comprises at least one of a packet data unit group delay budget (PSDB) or a packet data unit group loss rate (PSER).

Description

Technical Field

[0001] The present disclosure relates to the field of communication technology, and in particular to a transmission method, device and storage medium suitable for an extended reality service. Background Art

[0002] As one of the important application scenarios or services in 5G, AR (augmented reality) and VR (virtual reality) will fully evolve into XR extended reality in the 5G-Advanced and 6G era. XR services require high transmission rate, low latency and high reliability, which brings huge challenges to existing networks.

[0003] 3GPP Rel-18's research projects for XR services include XR perception, obtaining XR perception information for XR service transmission, studying and identifying XR traffic characteristics and QoS indicators, and application layer attributes for base station perception. In addition, it also includes studying how the above information supports XR service transmission.

[0004] There are multiple terminal devices in the XR scene, and each device may have multiple data streams (such as video streams, audio streams, and location information data streams). It is necessary to provide performance guarantees for multi-stream transmission. Therefore, it is necessary to study the QoS mechanism for XR services. Summary of the invention

[0005] One object of the present disclosure is to improve the transmission performance of XR services.

[0006] According to one aspect of some embodiments of the present disclosure, a transmission method suitable for extended reality services is proposed, including: establishing a PDU (Packet Data Unit) session between a user equipment UE and a core network, wherein the PDU session realizes extended reality XR service perception based on a PDU Set (Packet Data Unit), the PDU Set includes one or more PDUs, and the service quality QoS parameters of the PDU Set include at least one of PSDB (PDU-Set Delay Budget) or PSER (PDU-Set Error Rate, Packet Data Unit Group Loss Rate).

[0007] In some embodiments, the QoS parameters of the PDU Set also include PSIHI (PDU Set Integrated Handling Information), which is used to indicate whether the application layer needs all PDUs of the PDU Set.

[0008] In some embodiments, PDSB is used to describe the upper limit of the time period from the moment the first PDU is received to the moment all PDUs are successfully received in the PDU Set data packet; PSER is used to describe the upper limit of the non-congestion related PDU Set loss rate between RAN (Radio Access Network) and UE.

[0009] In some embodiments, the QoS parameters of the PDU Set are carried by a quality of service configuration parameter QoS profile sent by an SMF (Session Management Function) to the base station.

[0010] In some embodiments, the method complies with at least one of the following: one QoS flow corresponds to one or more PDU sets; or one PDU Set corresponds to one or more QoS flows.

[0011] In some embodiments, the PDSBs of one or more QoS flows corresponding to the PDU Set are the same.

[0012] In some embodiments, the PDSBs of one or more QoS flows corresponding to the PDU Set are different.

[0013] In some embodiments, the number of PDSBs in the QoS parameters of the PDU Set is 1, which is applied to both uplink and downlink.

[0014] In some embodiments, the number of PDSBs in the QoS parameters of the PDU Set is greater than 1, and a single PDSB is applied to the uplink or downlink.

[0015] In some embodiments, the PDSB is carried by a predetermined first structure, and the predetermined first structure includes the PDSB and an uplink identifier, or includes the PDSB and a downlink identifier.

[0016] In some embodiments, the PDSB in the QoS parameters of the PDU Set includes an uplink PDSB and a downlink PDSB.

[0017] In some embodiments, the PSERs of one or more QoS flows corresponding to the PDU Set are the same.

[0018] In some embodiments, the PSERs of one or more QoS flows corresponding to the PDU Set are different.

[0019] In some embodiments, the number of PSERs in the QoS parameter of the PSER is 1, which is applied to both the upstream and downstream directions.

[0020] In some embodiments, the number of PSERs in the QoS parameters of the PDU Set is greater than 1, and a single PSER is applied to the upstream direction or the downstream direction.

[0021] In some embodiments, the PSER is carried by a predetermined second structure, and the predetermined second structure includes the PESR and an uplink identifier, or includes the PESR and a downlink identifier.

[0022] In some embodiments, the PSER in the QoS parameters of the PDU Set includes an uplink PSER and a downlink PSER.

[0023] In some embodiments, the method further includes: determining that the PDU Set is received successfully when all PDUs in the PDU Set are received successfully.

[0024] In some embodiments, the method further includes: when PSIHI is not configured, if all PDUs in the PDU Set are received successfully, it is determined that the PDU Set is received successfully; when PSIHI is configured, if all PDUs required by the application layer are received successfully according to PSIHI, it is determined that the PDU Set is received successfully.

[0025] In some embodiments, the method also includes: determining that the PDU Set is received successfully when the proportion of successfully received PDUs in the PDU Set is greater than or equal to a predetermined proportion threshold, wherein the predetermined proportion threshold is determined based on at least one of the XR service type, high-layer signaling indication, core network signaling indication, and standard pre-defined.

[0026] In some embodiments, the method further includes: determining that the PDU Set is received successfully when all PDU Sets carrying the extended reality service data are completely received without duplicate contents.

[0027] In some embodiments, the method also includes at least one of the following: obtaining the priority of the PDU Set through the PDU Set priority parameter configured in the UPF (User Plane Function); obtaining the priority of the PDU Set through the parameters configured in the PDU session initiation or registration process; determining the priority of the PDU Set according to the PCF (Policy Control Function), and the priority is sent to the RAN through the SMF; determining the priority of the PDU Set according to the priority information of the PDU Set contained in the Qosprofile.

[0028] In some embodiments, the method further includes: performing traffic diversion with a PDU set corresponding to the QoS flow as a processing object through at least one of a Service Data Adaptation Protocol (SDAP) entity and a Packet Data Convergence Protocol (PDCP) entity.

[0029] In some embodiments, the traffic diversion taking the PDU set corresponding to the QoS flow as the processing object includes at least one of the following: the SDAP entity determines the DRB to which the PDU set is mapped; or the PDCP entity determines the RLC to which the data of the DRB is mapped.

[0030] In some embodiments, the SDAP entity determines the DRB to which the PDU set is mapped, including: the SDAP entity determines the DRB to which the sub-QoS flow is mapped.

[0031] In some embodiments, the SDAP entity determines the DRB to which the PDU set is mapped, including: the SDAP entity determines the DRB to which the QoS flow is mapped, including: according to the identifier of the PDU set, mapping PDUs with the same identifier to the same DRB, and mapping PDUs with different identifiers to the same or different DRBs.

[0032] In some embodiments, a sub-QoS flow corresponds to one or more PDU sets, and a QoS flow includes one or more sub-QoS flows.

[0033] In some embodiments, the SDAP entity supports mapping of sub-QoS flows to DRBs in both the uplink and downlink directions.

[0034] In some embodiments, the SDAP entity determines the DRB to which the PDU set is mapped in accordance with at least one of the following: the SDAP entity maps one or more sub-QoS flows to the same DRB; or the SDAP entity maps the same sub-QoS flow to only one DRB at a time in the uplink direction.

[0035] In some embodiments, one SDAP entity corresponds to multiple PDCP entities.

[0036] In some embodiments, the QoS flow includes a sub-QoS flow identifier and a QoS flow identifier, and the sub-QoS flow identifier corresponds to the sub-QoS flow one by one.

[0037] In some embodiments, the SDAP entity determines the DRB to which the sub-QoS flow is mapped, including: determining the DRB to which the sub-QoS flow is mapped according to a mapping relationship between the sub-QoS flow identifier and the DRB in the configuration parameters of the DRB.

[0038] In some embodiments, the PDCP entity is associated with one or more Radio Link Controls, RLCs.

[0039] In some embodiments, the PDCP entity determines the RLC to which to map the data of the DRB, including: the PDCP entity determines the RLC entity to which to map the sub-data radio bearer sub DRB, wherein the PDCP entity is associated with multiple RLCs, and the DRB includes one or more sub DRBs.

[0040] In some embodiments, the PDCP entity distinguishes sub DRBs according to a sub-QoS identifier, wherein the QoS flow includes one or more sub-QoS flows.

[0041] In some embodiments, the method further includes: when the PDCP entity determines that the sub DRB mode is not enabled, mapping the DRB data to the RLC entity uniquely corresponding to the PDCP entity.

[0042] In some embodiments, the method meets at least one of the following conditions: the characteristics of different sub-QoS flows are the same or different; the performance indicators of different sub-QoS flows are the same or different.

[0043] In some embodiments, the performance indicators of the sub-QoS flow include PDSB and PSER.

[0044] In some embodiments, the method further includes: when a timer for transmitting the PDU Set under test exceeds the PSER, the PDCP entity discards the PDU Set under test and one or more PDU Sets associated with the PDU Set under test.

[0045] According to one aspect of some embodiments of the present disclosure, a transmission device suitable for extended reality services is proposed, including a connection establishment unit, configured to establish a PDU session between a user equipment UE and a core network, wherein the PDU session implements extended reality XR service perception based on a PDU Set, the PDU Set includes one or more PDUs, and a quality of service QoS parameter of the PDU Set includes at least one of PSDB or PSER.

[0046] In some embodiments, the device also includes: a diversion unit, which is configured to perform diversion with the PDU set corresponding to the QoS flow as the processing object through at least one of the service data adaptation protocol SDAP entity and the packet data convergence protocol PDCP entity when the service quality QoS flow carries XR data.

[0047] According to one aspect of some embodiments of the present disclosure, a transmission device suitable for extended reality business is proposed, including: a memory; and a processor coupled to the memory, the processor being configured to execute any one of the above transmission methods suitable for extended reality business based on instructions stored in the memory.

[0048] According to one aspect of some embodiments of the present disclosure, a computer-readable storage medium is provided, on which computer program instructions are stored, and when the instructions are executed by a processor, the steps of any one of the above transmission methods applicable to an extended reality service are implemented. BRIEF DESCRIPTION OF THE DRAWINGS

[0049] The drawings described herein are used to provide further understanding of the present disclosure and constitute a part of the present disclosure. The illustrative embodiments of the present disclosure and their descriptions are used to explain the present disclosure and do not constitute improper limitations on the present disclosure.

[0050] Figure 1 It is a schematic diagram of the QoS architecture in the related technology.

[0051] Figure 2 It is a schematic diagram of some embodiments of the transmission method applicable to the extended reality service of the present disclosure.

[0052] Figure 3 The diagram is a schematic diagram of some embodiments of the relationship between PDU and PDU Set in the transmission method applicable to the extended reality service of the present disclosure.

[0053] Figure 4A It is a schematic diagram of some embodiments of the PDU Set processing flow in the transmission method applicable to the extended reality service of the present disclosure.

[0054] Figure 4B The diagram is a schematic diagram of some embodiments of QoS flows in the transmission method applicable to extended reality services of the present disclosure.

[0055] Figure 5 Schematic diagram of some embodiments of the transmission device applicable to the extended reality service of the present disclosure.

[0056] Figure 6 Schematic diagrams of other embodiments of the transmission device applicable to the extended reality service of the present disclosure.

[0057] Figure 7 Schematic diagrams of some further embodiments of the transmission device applicable to the extended reality service of the present disclosure. DETAILED DESCRIPTION

[0058] The technical solution of the present disclosure is further described in detail below through the accompanying drawings and embodiments.

[0059] In the related art, the QoS mechanism only supports the transmission of a single QoS flow and cannot provide performance guarantee for multiple related QoS flows.

[0060] At the NAS level, QoS Flow is the minimum granularity for QoS differentiation in a PDU session. In a PDU session, the QoS flow is identified by the QFI (QoS Flow ID) carried in the encapsulation header on the NG-U.

[0061] NG-RAN and 5GC ensure service quality (such as reliability and latency) by mapping packets to appropriate QoS flows and DRBs. The QoS architecture is as follows: Figure 1 shown.

[0062] In response to the above problems, the present disclosure proposes a transmission method, device and storage medium suitable for extended reality services, so as to adapt to the characteristics of multiple data stream transmission of XR services and ensure the transmission performance of XR services.

[0063] The transmission method for extended reality service of the present disclosure may be executed by the UE or by the core network. In some embodiments, the transmission method for extended reality service of the present disclosure is executed by the UE and the core network respectively.

[0064] Schematic diagrams of some embodiments of the transmission method applicable to the extended reality service of the present disclosure are as follows Figure 1 shown.

[0065] In step 101, a PDU session is established between the UE 11 and the core network 12. In some embodiments, the PDU session implements XR service perception based on a PDU Set. In some embodiments, each PDU Set includes one or more PDUs, such as Figure 2 As shown in Figure 2 The number of PDUs corresponding to each PDU Set is only an example and does not constitute an undue limitation on the present application. In some embodiments, the PDU session corresponding to the XR service includes one or more PDU Sets, and the PDU Set includes one or more PDUs. Different PDU Sets may correspond to the transmission of video, audio, position or action information, etc., or different PDUs in a single PDU Set may correspond to different parts of a frame or slice, such as video, audio, position or action information, etc.

[0066] In some embodiments, Figure 2As shown in , GOP (Group of Picture) includes I frames, P frames and B frames. I frame represents key frame, and the key frame picture is completely preserved. Only the data of this frame is needed for decoding. P frame represents one-way difference frame, which contains the difference between the current frame image and the previous I frame or P frame. When decoding, the difference defined by this frame needs to be superimposed with the previously cached picture to generate the final picture. B frame is a two-way difference frame, which records the difference between the current frame image and the previous and next frames. Multiple PDUs are generated for I frames, P frames and B frames respectively. The PDUs are grouped according to the corresponding frame types, and one or more PDU sets are generated for the PDU corresponding to each frame.

[0067] In some embodiments, Figure 2 As shown, multiple PDU sets correspond to one or more QoS flows. In some embodiments, a PDU Set corresponds to one or more QoS flows, and the same PDU Set can be located in the same or different QoS flows. This method can improve the flexibility of data flow transmission.

[0068] In some embodiments, the XR service QoS related parameter configuration information includes QoS parameters for PDU Set. In some embodiments, the QoS parameters of PDU Set include at least one of PSDB or PSER. In some embodiments, PDSB is used to describe the upper limit of the time period from the moment the first PDU is received to the moment when all PDUs are successfully received in the data packet of PDU Set, corresponding to the QoS parameter PDB of PDU; PSER is used to describe the upper limit of the non-congestion related PDU Set loss rate between RAN and UE, corresponding to the QoS parameter PER of PDU.

[0069] In some embodiments, the QoS parameters of the PDU Set also include PSIHI, which is used to indicate whether the application layer requires all PDUs of the PDU Set.

[0070] Through the method in the embodiment shown above, it is possible to perform session management of XR services in units of PDU Set, set QoS parameters in units of PDU Set, improve the transmission stream management efficiency and service quality assurance capability of XR services, thereby better adapting to the multi-stream transmission requirements of XR services and ensuring the transmission performance of XR services.

[0071] In some embodiments, one or more of the QoS parameters of the PDU Set mentioned above are sent to the QoS profile bearer of the base station via the SMF. This method is compatible with the QoS profile transfer process in related technologies, which is conducive to rapid deployment and implementation.

[0072] In some embodiments, the PDSB of one or more QoS flows corresponding to the PDU Set is the same, thereby reducing the difficulty of QoS guarantee of the PDU session and improving the stability.

[0073] In some embodiments, the PDSBs of one or more QoS flows corresponding to the PDU Set are different, thereby improving the flexibility of QoS guarantee of the PDU session.

[0074] In some embodiments, the number of PDSBs in the QoS parameter of the PDU Set is 1, which is applied to both uplink and downlink, that is, the same PDSB parameter is applied to both uplink and downlink, which reduces the difficulty of ensuring the quality of service.

[0075] In some embodiments, the number of PDSBs in the QoS parameter of the PDU Set is greater than 1, and a single PDSB is applied to the uplink or downlink, thereby facilitating the use of different service quality guarantees for the uplink and downlink service flows.

[0076] In some embodiments, when PDSB is configured for uplink and downlink respectively, the PDSB corresponding to the uplink or downlink can be marked. In some embodiments, the PDSB is carried by a predetermined first structure, and the predetermined first structure includes a PDSB and an uplink identifier, or includes a PDSB and a downlink identifier. In some embodiments, the PDSB in the QoS parameters of the PDU Set includes an uplink PDSB and a downlink PDSB, and the uplink and downlink PDSBs are easily identified by different name identifiers. Through such a method, it is easy to distinguish between the PDSBs used for uplink and downlink, and the reliability of service quality assurance is improved.

[0077] In some embodiments, the PSERs of one or more QoS flows corresponding to the PDU Set are the same, thereby reducing the difficulty of QoS guarantee for the PDU session and improving stability.

[0078] In some embodiments, the PSERs of one or more QoS flows corresponding to the PDU Set are different, thereby improving the flexibility of QoS guarantee of the PDU session.

[0079] In some embodiments, the number of PSERs in the QoS parameter of the PSER is 1, which is applied to both the uplink and downlink directions, that is, the same PDSB parameter is applied to both the uplink and downlink directions, which reduces the difficulty of ensuring the quality of service.

[0080] In some embodiments, the number of PSERs in the QoS parameters of the PDU Set is greater than 1, and a single PSER is applied to the uplink direction or the downlink direction, thereby facilitating different service quality guarantees for uplink and downlink service flows.

[0081] In some embodiments, when PDSB is configured for uplink and downlink respectively, the PDSB corresponding to the uplink or downlink can be marked. In some embodiments, the PSER is carried by a predetermined second structure, and the predetermined second structure includes a PESR and an uplink identifier, or includes a PESR and a downlink identifier. In some embodiments, the PSER in the QoS parameters of the PDU Set includes an uplink PSER and a downlink PSER. Through such a method, it is easy to distinguish the PSER used for uplink and downlink, and improve the reliability of service quality assurance.

[0082] In some embodiments, the transmission method for extended reality services disclosed herein further includes determining whether the PDU Set is received successfully. In some embodiments, if the PDU Set is not received successfully, a retransmission operation may be triggered. Different standards may be used to determine whether the PDU Set is received successfully, thereby increasing the flexibility of the XR service.

[0083] In some embodiments, when all PDUs in the PDU Set are received successfully, it is determined that the PDU Set is received successfully, thereby improving the comprehensiveness and integrity of XR service data transmission.

[0084] In some embodiments, if PSIHI is not configured, if all PDUs in the PDU Set are received successfully, it is determined that the PDU Set is received successfully; if PSIHI is configured, if all PDUs required by the application layer are received successfully according to PSIHI, it is determined that the PDU Set is received successfully. Through such a method, on the basis of improving the comprehensiveness and integrity of XR service data transmission, the needs of the application layer can be taken into account to reduce network transmission pressure and improve data timeliness.

[0085] In some embodiments, when the ratio of successfully received PDUs in the PDU Set to all PDUs in the PDU Set is greater than or equal to a predetermined ratio threshold, it is determined that the PDU Set is received successfully, wherein the predetermined ratio threshold is determined based on at least one of the XR service type, high-layer signaling indication, core network signaling indication, and standard pre-definition. Such a method is conducive to controlling the service quality of the XR service within a predetermined range, reducing the pressure on network transmission and equipment, and improving the fluency of the service.

[0086] In some embodiments, when all PDU Sets carrying XR service data are completely received without duplicate content, it is determined that the PDU Set is received successfully, thereby reducing the network transmission pressure on the basis of ensuring the comprehensiveness and integrity of XR service data transmission.

[0087] In some embodiments, the transmission method for extended reality services disclosed herein further includes obtaining the priority of a PDU Set. In some embodiments, the priority of a PDU Set may be configured and obtained in at least one of the following ways, thereby improving the flexibility of configuring and obtaining the priority of a PDU Set.

[0088] In some embodiments, the priority of PDU Set is completed on the UPF side, for example, the PS Priority Level is configured in PDU Set (PS) 5QI, and the smaller the value, the higher the priority. The priority of PDU Set is obtained through the PDU Set priority level parameter configured in UPF.

[0089] In some embodiments, the priority of the PDU Set is configured through a PDU session initiation or registration process, and the priority of the PDU Set is obtained through parameters configured in the PDU session initiation or registration process.

[0090] In some embodiments, the priority of the PDU Set is determined by the PCF and sent to the RAN by the SMF. The UE can obtain the priority of the PDU Set through the RAN.

[0091] In some embodiments, the QoS profile includes a priority setting of the PDU Set, such as PSI (PDU Set Importance), which is used to identify the relative priority between PDU Sets. The priority of the PDU Set is determined according to the priority information of the PDU Set included in the QoS profile.

[0092] In some embodiments, the transmission method for extended reality services disclosed herein further includes performing traffic diversion with the PDU set corresponding to the QoS flow as the processing object through at least one of an SDAP entity and a PDCP entity. In some embodiments, performing traffic diversion with the PDU set corresponding to the QoS flow as the processing object through the SDAP entity includes: the SDAP entity determines the DRB to which the PDUset is mapped, such as Figure 4A In some embodiments, the PDCP entity performs the offloading with the PDU set corresponding to the QoS flow as the processing object, including: the PDCP entity determines the RLC to which the DRB data is mapped, such as Figure 4A As shown, it is performed in the stage from PDCP to RLC. In some embodiments, the PDCP entity is associated with one or more radio link control RLCs.

[0093] Through this method, in at least one link, the QoS flow can be diverted with the PDU set corresponding to the QoS flow as the processing object, realizing diversion with PDU set as the granularity, supporting multi-flow processing of XR services, and improving the flexibility of QoS flow processing and business adaptability.

[0094] In some embodiments, the operation of the SDAP entity determining the DRB to which the PDU set is mapped may be achieved by directly splitting the QoS flow, or by splitting one or more sub-QoS flows included in the QoS flow.

[0095] In some embodiments, the SDAP entity can directly divert the QoS flow. The SDAP entity maps PDUs with the same identifier to the same DRB and maps PDUs with different identifiers to the same or different DRBs according to the identifier of the PDU set, thereby implementing the diversion operation on the QoS flow.

[0096] In some embodiments, the QoS flow may include one or more sub-QoS flows, and the SDAP entity determines that the DRB to which the PDUset is mapped may be implemented by determining the DRB to which each sub-QoS flow is mapped. In some embodiments, the SDAP entity determines that the DRB to which the PDU set is mapped meets at least one of the following conditions: the SDAP entity maps one or more sub-QoS flows to the same DRB; or the SDAP entity maps the same sub-QoS flow to only one DRB at a time in the uplink direction. In this way, the sub-QoS flows included in the QoS flow can be diverted.

[0097] In some embodiments, the QoS flow includes a sub-QoS flow identifier and a QoS flow identifier, and the sub-QoS flow identifier corresponds to the sub-QoS flow. Figure 4B As shown, a QoS flow identifier QFI is included, and each sub-QoS flow includes a sub-QoS flow identifier PSQFI. Through this method, the QoS flow can be identified based on the QFI, and each sub-QoS flow can be identified according to the PSQFI, ensuring the accuracy of sub-QoS identification and subsequent processing.

[0098] In some embodiments, a PDCP entity is associated with multiple RLCs, and a DRB includes one or more sub DRBs. In some embodiments, an XR-moreThanOneRLC configuration is added to the PDCP config definition part. In an XR service, one PDCP entity supports one or more corresponding RLC entities. In some embodiments, the configuration information added in the PDCP config may be as follows:

[0099] XR-moreThanOneRLC SEQUENCE{

[0100] PrimaryPath SEQUENCE{

[0101] cellGroup CellGroupId OPTIONAL,

[0102] logicalChannel LogicalChannelIdentity OPTIONAL

[0103] },

[0104] ul-DataSplitThreshold UL-DataSplitThreshold OPTIONAL, sub-DRB BOOLEANOPTIONAL

[0105] } OPTIONAL

[0106] The PDCP entity corresponds to one or more sub DRBs, and the SDAP entity can determine the sub DRB to which each PDU set in the QoS flow is mapped. The operation of the PDCP entity determining the RLC to which the DRB data is mapped can be implemented by the PDCP entity determining the RLC entity to which each sub DRB is mapped. In some embodiments, the PDCP entity distinguishes sub DRBs according to the sub-QoS identifier, wherein the QoS flow includes one or more sub-QoS flows. Through such a method, the diversion operation for the sub DRB can be implemented in the PDCP.

[0107] In some embodiments, when the PDCP entity determines that the sub DRB mode is not enabled, the PDCP entity maps the DRB data to the RLC entity uniquely corresponding to the PDCP entity, thereby implementing QoS flow processing when the sub DRB mode is not enabled and improving transmission reliability.

[0108] In some embodiments, the characteristics of different sub-QoS flows may be the same or different. In some embodiments, the performance indicators of different sub-QoS flows may be the same or different. In some embodiments, the performance indicators of sub-QoS flows include PDSB and PSER.

[0109] In this way, it is possible to manage the service flow in units of sub-QoS flows, thereby improving the management flexibility of the service flow.

[0110] In some embodiments, the transmission method for extended reality services disclosed in the present invention also includes that when the timer for the PDCP entity to transmit the PDU Set under test exceeds the PSER, the PDCP entity discards the PDU Set under test and one or more PDU Sets associated with the PDU Set under test, thereby promptly discovering data that cannot be used normally even if transmitted and stopping processing, reducing unnecessary subsequent processing and transmission operations, reducing the burden of subsequent processing and data transmission, reducing resource consumption, and achieving energy saving.

[0111] In some embodiments, the QoS parameters of the PDU Set include at least one of PSDB, PSER or PSIHI.

[0112] 1) PSDB is used to describe the upper limit of the time period from the moment the first PDU is received in the data packet of the PDU set to the time when all PDUs in the PDU set are successfully received. PSDB corresponds to the QoS parameter PDB of the QoS flow of the traditional service PDU session. The (one or more) QoS flows corresponding to the PDU Set of the XR service PDU session can use the same or different PSDBs.

[0113] In some embodiments, for the XR service of the UE, when a single PSDB is configured, it can be applied to both the uplink and downlink.

[0114] In some embodiments, multiple PDSBs can be configured and applied to uplink and downlink respectively, and distinguished by using identifiers. For example, method 1: using the structure {PSDB, identifier A} for identification, indicating that A can take the value 0 or 1, one of 0 and 1 is used to indicate that the corresponding PDSB is applied to the uplink, and the other is used to indicate that the corresponding PDSB is applied to the downlink; method 2: using different identifier names to distinguish PDSB_DL (downlink PDSB) and PDSB_UL (uplink PDSB).

[0115] 2) PSER is used to describe the upper limit of the non-congestion related PDU Set loss rate between RAN and UE. PSER corresponds to the QoS parameter PER of the QoS flow of the traditional service PDU session. The (one or more) QoS flows corresponding to the PDU Set of the XR service PDU session can use the same or different PSER.

[0116] In some embodiments, for the XR service of the UE, when a single PSER is configured, it can be applied to both the uplink and the downlink.

[0117] In some embodiments, multiple PSERs can be configured and applied to uplink and downlink respectively, and distinguished by using identifiers. For example, method 1: using the structure {PSER, identifier B} for identification, identifier B can take the value 0 or 1, one of 0 and 1 is used to indicate that the corresponding PSER is applied to the uplink, and the other is used to indicate that the corresponding PSER is applied to the downlink; method 2: using different identifier names to distinguish PSER_DL (downlink PSER) and PSER_UL (uplink PSER).

[0118] 3) PSIHI is used to indicate whether the application layer needs the PDUs of all PDU Sets.

[0119] Through this method, QoS parameters can be set in units of PDU Set, improving the transmission flow management efficiency and service quality assurance capabilities of XR services.

[0120] In some embodiments, the QoS parameters corresponding to the PDU Set mentioned above may be determined by one of the following methods for measuring the success of PDU Set reception:

[0121] When all PDUs in a PDU Set are received successfully, the PDU Set is received successfully;

[0122] The value of X in PDU Set depends on PSIHI. When PSIHI is not configured, it is considered that all PDUs in PDU Set are received successfully. When PSIHI is configured, it is determined according to PSIHI configuration. When all PDUs required by the application layer are received successfully, it is considered that PDU Set is received successfully.

[0123] When X percentage of PDUs in a PDU Set are received successfully, the PDU Set is received successfully. X is defined as follows:

[0124] The proportion of standard-defined X is determined according to at least one of the XR service type, high-layer signaling indication, core network signaling indication, and standard pre-definition;

[0125] When PDU Set considers improving the reliability of XR services, the PDU Set is received successfully when all PDU Sets carrying XR service data are completely received without duplicate content.

[0126] In some embodiments, the PDU session corresponding to the XR service includes one or more PDU Sets, each PDU Set includes one or more PDUs, and different PDU Sets may correspond to the transmission of video, audio, position / action information, etc., or different PDUs in a single PDU Set correspond to different parts of a frame or slice, such as video, audio, position / action information, etc.

[0127] In some embodiments, the PDU session of the XR service may include one or more QoS flows, and different PDU Sets may correspond to one or the same QoS flow, or may correspond to different QoS flows; or, for the XR service, the concept of sub-QoS flow is introduced, and different PDU Sets correspond to different sub QoS flows, and different sub-QoS flows constitute a QoS flow, that is, a QoS flow includes one or more sub-QoS flows. The characteristics and performance indicators of different sub-QoS flows may be the same or different.

[0128] In some embodiments, the characteristics of the sub-QoS flow are characterized by PDU Set 5QI to describe the sub-QoS characteristics based on the PDU set.

[0129] In some embodiments, when sub-QoS flows are introduced, a QoS flow includes at least one sub-QoS flow. The data packet header of the QoS flow includes QFI and PSQFI parameters. PSQFI is a value, similar to the QFI value of the original PDU-based QoS mechanism, corresponding to PS5QI (PDU Set 5QI). There is only one QFI value in a single QoS flow, and there are one or more PSQFI values.

[0130] In some embodiments, the implementation method of the transmission / mapping mechanism with QoS flow based on PDU set includes completing the mapping of QoS flow to DRB at the SDAP layer and completing the mapping of DRB to RLC channel at the PDCP layer.

[0131] In some embodiments, mapping may be performed at the SDAP layer.

[0132] The SDAP layer QoS flow can be a QoS or sub-QoS flow, which is referred to as a QoS flow in this embodiment.

[0133] On the UPF side, XR data is carried on QoS-based flows. Through the SDAP layer, the mapping of QoS flows to DRBs is completed. The following situations may exist:

[0134] SDAP supports mapping of QoS flows to DRBs. QoS flows can map PDUs with different PDU Set identifiers to the same or different DRBs.

[0135] SDAP performs DRB mapping based on whether there is a sub-QoS flow. If there is no sub-QoS flow, a single QoS flow is mapped to a single DRB; if there is a sub-QoS flow, it is mapped according to the sub-QoS flow, and the sub-QoS flow is mapped to the same or different DRBs, that is, one SDAP entity is supported to correspond to multiple PDCP entities. The sub-QoS flow is distinguished by the PSQFI value and mapped to the corresponding DRB. By modifying the SDAP layer protocol in the relevant technology, it supports different DRBs to carry QoS flows with the same QFI mark, that is, the QFI value is not unique; the newly added PSQFI value is unique. For the uplink, for the parameter configuration of the DRB, add a mapping list from PSQFI to DRB. The uplink data completes the mapping of sub-QoS to DRB according to the mapping list.

[0136] Through this method, it is possible to support multi-stream processing of XR services at the SDAP layer and ensure the transmission performance of XR services.

[0137] In some embodiments, DRB mapping to RLC channels may be done at the PDCP layer.

[0138] DRB can be DRB or sub-DRB, referred to as DRB in this embodiment.

[0139] On the UPF side, XR data is carried on QoS or sub-QoS flows. Through the SDAP protocol, the mapping of QoS flows to DRBs is completed, and DRBs correspond to a PDCP entity.

[0140] Define the sub-DRB resource bearer type for mapping PDUs with different PDU set identifiers in a sub-QoS flow or a QoS flow to a sub-DRB.

[0141] If the sub-DRB mode is not enabled, then in the absence of other configurations, one PDCP entity corresponds to one RLC entity, and the data on the DRB is mapped to the corresponding RLC channel.

[0142] If the sub-DRB mode is enabled, one PDCP entity can correspond to multiple RLC entities, which is equivalent to a DRB including one or more sub-DRBs. Sub-QoS flows correspond to sub-DRBs, and different sub-QoS or sub-DRBs are distinguished based on the PSQFI identifier.

[0143] The sub-DRB data is mapped to the corresponding RLC channel.

[0144] For the packet loss mechanism, if the timer for PDU set transmission exceeds the specified PSDB value, the PDU set or other PDU sets related thereto are discarded at the PDCP layer to reduce resource consumption and achieve energy saving.

[0145] Through this method, it is possible to support multi-stream processing of XR services at the PDCP layer and ensure the transmission performance of XR services.

[0146] Schematic diagrams of some embodiments of the transmission device applicable to the augmented reality service of the present disclosure are as follows Figure 5 In some embodiments, the transmission device applicable to the extended reality service may be located in the core network, or may be located in the UE, or may be deployed in the core network and the UE respectively.

[0147] The connection establishment unit 501 is capable of establishing a PDU session between the user equipment UE and the core network. In some embodiments, a transmission device suitable for extended reality services located in the UE can establish a PDU session with the core network; a transmission device suitable for extended reality services located in the core network can establish a PDU session with the UE. In some embodiments, the PDU session implements XR service perception based on a PDU Set. In some embodiments, each PDU Set includes one or more PDUs. In some embodiments, the PDU session corresponding to the XR service includes one or more PDU Sets, and the PDU Set includes one or more PDUs. Different PDU Sets may correspond to the transmission of video, audio, position or action information, etc., or different PDUs in a single PDUSet correspond to different parts of a frame or slice, such as video, audio, position or action information, etc.

[0148] In some embodiments, the XR service QoS related parameter configuration information includes QoS parameters for PDU Set. In some embodiments, the QoS parameters of PDU Set include at least one of PSDB or PSER. In some embodiments, PDSB is used to describe the upper limit of the time period from the moment the first PDU is received to the moment when all PDUs are successfully received in the data packet of PDU Set, corresponding to the QoS parameter PDB of PDU; PSER is used to describe the upper limit of the non-congestion related PDU Set loss rate between RAN and UE, corresponding to the QoS parameter PER of PDU.

[0149] In some embodiments, the QoS parameters of the PDU Set also include PSIHI, which is used to indicate whether the application layer requires all PDUs of the PDU Set.

[0150] The transmission device suitable for extended reality services in the above-mentioned embodiment can perform session management of XR services in units of PDU Set, set QoS parameters in units of PDU Set, improve the transmission stream management efficiency and service quality assurance capability of XR services, thereby better adapting to the multi-stream transmission requirements of XR services and ensuring the transmission performance of XR services.

[0151] In some embodiments, Figure 5 As shown, the transmission device suitable for extended reality services also includes a diversion unit 502, which can perform diversion with the PDU set corresponding to the QoS flow as the processing object through at least one of the SDAP entity and the PDCP entity when the QoS flow carries XR data. In some embodiments, the diversion unit can be based on any of the methods mentioned above for diversion by the SDAP entity and the PDCP.

[0152] Such a transmission device suitable for extended reality services can support XR service multi-stream processing in at least one layer of the SDAP and PDCP layers, thereby ensuring the transmission performance of the XR services.

[0153] In some embodiments, the connection establishment unit 501 can also determine whether the PDU Set is received successfully during the interaction between the UE and the core network, and the method for determining whether the reception is successful can adopt any of the methods mentioned above. Such a device can promptly determine whether the reception is successful, so as to facilitate timely response and improve service assurance capabilities.

[0154] In some embodiments, the shunt unit 502 can also cause the PDCP entity to discard the PDU Set under test and one or more PDU Sets associated with the PDU Set under test when the timer of the PDU Set under test exceeds the PSER. Such a device can timely discover data that cannot be used normally even if it is transmitted and stop processing, reduce unnecessary subsequent processing and transmission operations, reduce the burden of subsequent processing and data transmission, reduce resource consumption, and achieve energy saving effects.

[0155] The structural schematic diagram of some embodiments of the transmission device applicable to the augmented reality service of the present disclosure is as follows Figure 6As shown. A transmission device suitable for extended reality services includes a memory 601 and a processor 602. Wherein: the memory 601 can be a disk, a flash memory, or any other non-volatile storage medium. The memory is used to store the instructions in the corresponding embodiment of the transmission method suitable for extended reality services described above. The processor 602 is coupled to the memory 601 and can be implemented as one or more integrated circuits, such as a microprocessor or a microcontroller. The processor 602 is used to execute instructions stored in the memory, and can adapt to the multi-stream transmission requirements of the XR service to ensure the transmission performance of the XR service.

[0156] In one embodiment, it is also possible to Figure 7 As shown, the transmission device 700 suitable for the extended reality service includes a memory 701 and a processor 702. The processor 702 is coupled to the memory 701 via a BUS bus 703. The transmission device 700 suitable for the extended reality service can also be connected to an external storage device 705 through a storage interface 704 to call external data, and can also be connected to a network or another computer system (not shown) through a network interface 706. No detailed description will be given here.

[0157] In this embodiment, the memory stores data instructions, and the processor processes the instructions, so as to adapt to the multi-stream transmission requirements of the XR service and ensure the transmission performance of the XR service.

[0158] In another embodiment, a computer-readable storage medium stores computer program instructions thereon, which, when executed by a processor, implement the steps of the method in the corresponding embodiment of the transmission method applicable to the extended reality business. It should be understood by those skilled in the art that the embodiments of the present disclosure may be provided as methods, devices, or computer program products. Therefore, the present disclosure may take the form of a complete hardware embodiment, a complete software embodiment, or an embodiment combining software and hardware. Moreover, the present disclosure may take the form of a computer program product implemented on one or more computer-usable non-transient storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0159] The present disclosure is described with reference to flowcharts and / or block diagrams of methods, devices (systems) and computer program products according to embodiments of the present disclosure. It should be understood that each process and / or block in the flowchart and / or block diagram and the combination of processes and / or blocks in the flowchart and / or block diagram can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor or other programmable data processing device to produce a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowchart and / or block diagram. Figure 1A process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0160] These computer program instructions may also be stored in a computer-readable memory capable of directing a computer or other programmable data processing device to operate in a specific manner, so that the instructions stored in the computer-readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1 A process or multiple processes and / or boxes Figure 1 A function specified in one or more boxes.

[0161] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operating steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing instructions for implementing the process. Figure 1 A process or multiple processes and / or boxes Figure 1 The steps for the functions specified in one or more boxes.

[0162] So far, the present disclosure has been described in detail. In order to avoid obscuring the concept of the present disclosure, some details known in the art are not described. Based on the above description, those skilled in the art can fully understand how to implement the technical solution disclosed here.

[0163] The method and apparatus of the present disclosure may be implemented in many ways. For example, the method and apparatus of the present disclosure may be implemented by software, hardware, firmware, or any combination of software, hardware, and firmware. The above order of steps for the method is for illustration only, and the steps of the method of the present disclosure are not limited to the order specifically described above, unless otherwise specifically stated. In addition, in some embodiments, the present disclosure may also be implemented as a program recorded in a recording medium, which includes machine-readable instructions for implementing the method according to the present disclosure. Therefore, the present disclosure also covers a recording medium storing a program for executing the method according to the present disclosure.

[0164] It should be noted that the terms "first", "second", etc. in the specification, claims, and drawings of the present disclosure are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the data used in this way can be interchangeable where appropriate, so that the embodiments of the present disclosure described herein can be implemented in an order other than those illustrated or described herein. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions, for example, a process, method, system, product, or device that includes a series of steps or units is not necessarily limited to those steps or units that are clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products, or devices.

[0165] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the present disclosure rather than to limit it. Although the present disclosure has been described in detail with reference to the preferred embodiments, ordinary technicians in the relevant field should understand that the specific implementation methods of the present disclosure can still be modified or some technical features can be replaced by equivalents without departing from the spirit of the technical solution of the present disclosure, which should be included in the scope of the technical solution for protection of the present disclosure.

Claims

1. A transmission method applicable to an extended reality service, comprising: Establish a packet data unit (PDU) session between the user equipment (UE) and the core network. Among them, the PDU session realizes extended reality XR service perception based on the packet data unit group PDU Set, the PDU Set includes one or more PDUs, and the service quality QoS parameters of the PDU Set include at least one of the packet data unit group delay budget PSDB or the packet data unit group loss rate PSER.

2. The method according to claim 1, wherein: The QoS parameters of the PDU Set also include packet data unit group integrated processing information PSIHI, which is used to indicate whether the application layer needs all PDUs of the PDU Set.

3. The method according to claim 1, wherein: The PDSB is used to describe the upper limit of the time period from the moment the first PDU is received to the moment when all PDUs are successfully received in the data packet of the PDU Set; The PSER is used to describe the upper limit of the non-congestion related PDU Set loss rate between the radio access network RAN ​​and the UE.

4. The method according to claim 1, 2 or 3, wherein: The QoS parameters of the PDU Set are carried by the service quality configuration parameter QoS profile sent by the session management function SMF to the base station.

5. The method according to claim 1, wherein: The method meets at least one of the following requirements: A QoS flow corresponds to one or more PDU sets; or A PDU Set corresponds to one or more QoS flows.

6. The method according to claim 5, wherein: The PDSB of one or more QoS flows corresponding to the PDU Set is the same.

7. The method according to claim 5, wherein: The PDSB of one or more QoS flows corresponding to the PDU Set is different.

8. The method according to any one of claims 1 to 7, wherein: The number of PDSBs in the QoS parameters of the PDU Set is 1, which is applied to both uplink and downlink.

9. The method according to any one of claims 1 to 7, wherein: The number of the PDSBs in the QoS parameters of the PDU Set is greater than 1, and a single PDSB is applied to uplink or downlink.

10. The method according to claim 9, wherein: The PDSB is carried by a predetermined first structure, and the predetermined first structure includes the PDSB and an uplink identifier, or includes the PDSB and a downlink identifier.

11. The method according to claim 9, wherein: The PDSB in the QoS parameters of the PDU Set includes an uplink PDSB and a downlink PDSB.

12. The method according to claim 5, wherein: The PSER of one or more QoS flows corresponding to the PDU Set is the same.

13. The method according to claim 5, wherein: The PSERs of one or more QoS flows corresponding to the PDU Set are different.

14. The method according to claim 1 to 4, 12 or 13, wherein: The number of PSERs in the QoS parameter of the PSER is 1, which is applied to both the uplink direction and the downlink direction.

15. The method according to claim 1 to 4, 12 or 13, wherein: The number of the PSERs in the QoS parameters of the PDU Set is greater than 1, and a single PSER is applied to an uplink direction or a downlink direction.

16. The method according to claim 15, wherein: The PSER is carried by a predetermined second structure, and the predetermined second structure includes the PESR and an uplink identifier, or includes the PESR and a downlink identifier.

17. The method according to claim 15, wherein: The PSER in the QoS parameters of the PDU Set includes an uplink PSER and a downlink PSER.

18. The method according to any one of claims 1 to 4, further comprising: In the case where all PDUs in the PDU Set are received successfully, it is determined that the PDU Set is received successfully.

19. The method according to claim 2, further comprising: In the case where the PSIHI is not configured, if all PDUs in the PDU Set are received successfully, it is determined that the PDU Set is received successfully; In the case where the PSIHI is configured, if it is determined according to the PSIHI that all PDUs required by the application layer are received successfully, it is determined that the PDU Set is received successfully.

20. The method of claim 1, further comprising: When the proportion of successfully received PDUs in the PDU Set to all PDUs in the PDU Set is greater than or equal to a predetermined proportion threshold, it is determined that the PDU Set is received successfully, wherein the predetermined proportion threshold is determined based on at least one of the XR service type, high-layer signaling indication, core network signaling indication, and standard pre-definition.

21. The method of claim 1, further comprising: When all PDU Sets carrying extended reality service data are completely received without duplicate content, it is determined that the PDU Set is received successfully.

22. The method of claim 1, further comprising at least one of the following: Obtaining the priority of the packet data unit group through the PDU Set priority parameter configured in the user plane function unit UPF; Obtaining the priority of the PDU Set through the parameters configured in the PDU session initiation or registration process; Determine the priority of the PDU Set according to the policy control function PCF, and send the priority to the RAN via the SMF; The priority of the PDU Set is determined according to the priority information of the PDU Set included in the Qos profile.

23. The method of claim 1, further comprising: At least one of a service data adaptation protocol (SDAP) entity and a packet data convergence protocol (PDCP) entity is used to perform traffic diversion with the PDU set corresponding to the QoS flow as a processing object.

24. The method according to claim 23, wherein: The traffic diversion taking the PDU set corresponding to the QoS flow as the processing object includes at least one of the following: The SDAP entity determines a DRB to which to map the PDU set; or The PDCP entity determines the RLC to which the data of the DRB is mapped.

25. The method according to claim 24, wherein: The SDAP entity determines that the DRB to which the PDU set is mapped includes: The SDAP entity determines the DRB to which the sub-QoS flow is mapped.

26. The method according to claim 24, wherein: The SDAP entity determines that the DRB to which the PDU set is mapped includes: The SDAP entity determines the DRB to which the QoS flow is mapped, including: mapping the PDUs with the same identifier to the same DRB according to the identifier of the PDU set, and mapping the PDUs with different identifiers to the same or different DRBs.

27. The method according to claim 25, wherein: The sub-QoS flow corresponds to one or more of the PDU sets, and the QoS flow includes one or more of the sub-QoS flows.

28. The method according to claim 25 or 27, wherein: The SDAP entity supports mapping of sub-QoS flows and DRBs in the uplink and downlink directions.

29. The method according to claim 25 or 27, wherein: The SDAP entity determines that the DRB to which the PDU set is mapped meets at least one of the following conditions: The SDAP entity maps one or more sub-QoS flows to the same DRB; or The SDAP entity maps the same sub-QoS flow to only one DRB at a time in the uplink direction.

30. The method of claim 23, wherein: One SDAP entity corresponds to a plurality of PDCP entities.

31. The method according to claim 25 or 27, wherein: The QoS flow includes a sub-QoS flow identifier and a QoS flow identifier, and the sub-QoS flow identifier corresponds to the sub-QoS flow in a one-to-one manner.

32. The method according to claim 31, wherein: The SDAP entity determines that the DRB to which the sub-QoS flow is mapped includes: The DRB to which the sub-QoS flow is mapped is determined according to the mapping relationship between the sub-QoS flow identifier and the DRB in the configuration parameters of the DRB.

33. The method of claim 23, wherein: The PDCP entity is associated with one or more Radio Link Controls RLCs.

34. The method of claim 24, wherein: The PDCP entity determines that the RLC to which the data of the DRB is mapped includes: The PDCP entity determines an RLC entity to which a sub-data radio bearer sub DRB is mapped, wherein the PDCP entity is associated with multiple RLCs, and the DRB includes one or more of the sub DRBs.

35. The method of claim 34, wherein: The PDCP entity distinguishes the subDRB according to a sub-QoS identifier, wherein the QoS flow includes one or more sub-QoS flows.

36. The method of claim 23, further comprising: When determining that the sub DRB mode is not enabled, the PDCP entity maps the DRB data to the RLC entity uniquely corresponding to the PDCP entity.

37. The method of claim 25, wherein: The method meets at least one of the following requirements: The characteristics of different sub-QoS flows are the same or different; The performance indicators of different sub-QoS flows may be the same or different.

38. The method of claim 37, wherein: The performance indicators of the sub-QoS flow include PDSB and PSER.

39. The method of claim 23, further comprising: In a case where the timer for transmitting the PDU Set under test exceeds the PSER, the PDCP entity discards the PDU Set under test and one or more PDU Sets associated with the PDU Set under test.

40. A transmission device for an extended reality service, comprising a connection establishment unit configured to establish a packet data unit (PDU) session between a user equipment (UE) and a core network, in, The PDU session realizes the extended reality XR service perception based on the packet data unit group PDU Set. The PDU Set includes one or more PDUs. The service quality QoS parameters of the PDU Set include at least one of the packet data unit group delay budget PSDB or the packet data unit group loss rate PSER.

41. The apparatus of claim 40, further comprising: The diversion unit is configured to perform diversion with the PDU set corresponding to the QoS flow as the processing object through at least one of the service data adaptation protocol SDAP entity and the packet data convergence protocol PDCP entity when the service quality QoS flow carries XR data.

42. A transmission device suitable for an extended reality service, comprising: Memory; as well as A processor coupled to the memory, the processor being configured to execute the method according to any one of claims 1 to 39 based on instructions stored in the memory.

43. A computer-readable storage medium having computer program instructions stored thereon, which, when executed by a processor, implement the steps of the method described in any one of claims 1 to 39.

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